QPL 2006 Preliminary Version From reversible to irreversible computations Abstract

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J.Nanopart.Res.,2009,11,1513–Rheological behaviour of ethylene glycol-titanate nanotube nano

BRIEF COMMUNICATIONRheological behaviour of ethylene glycol-titanate nanotube nanoﬂuidsHaisheng Chen ÆYulong Ding ÆAlexei Lapkin ÆXiaolei FanReceived:11July 2008/Accepted:4February 2009/Published online:26February 2009ÓSpringer Science+Business Media B.V.2009Abstract Experimental work has been performed on the rheological behaviour of ethylene glycol based nanoﬂuids containing titanate nanotubes over 20–60°C and a particle mass concentration of 0–8%.It is found that the nanoﬂuids show shear-thinning behaviour particularly at particle concentrations in excess of *2%.Temperature imposes a very strong effect on the rheological behaviour of the nanoﬂuids with higher temperatures giving stronger shear thinning.For a given particle concentration,there exists a certain shear rate below which the viscosity increases with increasing temperature,whereas the reverse occurs above such a shear rate.The normalised high-shear viscosity with respect to the base liquid viscosity,however,is independent of temperature.Further analyses suggest that the temperature effects are due to the shear-dependence of the relative contributions to the viscosity of the Brownian diffusion and convection.The analyses also suggest that a combination of particle aggregation and particle shape effects is the mechanism for the observed high-shear rheological behaviour,which is also supported by the thermal conductivity measure-ments and analyses.Keywords Rheological behaviour ÁEthylene glycol ÁTitanate nanotube ÁNanoﬂuid ÁThermal conductivityNanoﬂuids are dilute suspensions of particles with at least one dimension smaller than about 100nm (Choi 1995).Such a type of materials can be regarded as functionalized colloids with special requirements of a low-particle loading,a high-thermal performance,favourable ﬂow/rheolgocial behaviour,and a great physical and chemical stability over a wide range of process and solution chemistry conditions.Nano-ﬂuids have been shown to be able to enhance heat transfer (Choi 1995;Wang and Mujumdar.2007),mass transfer (Krishnamurthy et al.2006),and wetting and spreading (Wasan and Nikolov 2003),and have been a hot topic of research over the past decade (Wang and Mujumdar 2007;Keblinski et al.2005).Most published studies have focused on the heat transfer behaviour including thermal conduction (Choi 1995;Wang et al.1999;Wang and Mujumdar 2007;Keblinski et al.2005;Eastman et al.2001;He et al.2007;Ding et al.2006),phase change (boiling)heat transfer (Das et al.2003;Pak and Cho 1998),and convective heat transfer (Wang and Mujumdar 2007;Keblinski et al.2005;He et al.2007;Ding et al.2006,Chen et al.2008;Prasher et al.2006a and Yang et al.2005).Only few studies have been devoted to the rheological behaviour ofH.Chen ÁY.Ding (&)Institute of Particle Science and Engineering,University of Leeds,Leeds,UK e-mail:y.ding@pkin ÁX.FanDepartment of Chemical Engineering,University of Bath,Bath,UKJ Nanopart Res (2009)11:1513–1520DOI 10.1007/s11051-009-9599-9nanoﬂuids(He et al.2007;Chen et al.2008;Prasher et al.2006a,b;Kwak and Kim2005;Lee et al.2006), although there is a large body of literature on suspensions rheology;see for example,Russel et al. (1991);Chow(1993);Petrie(1999),Larson(1999); Goodwin et al.(2000)l;Mohraz et al.(2004);Larson (2005);Egres and Wagner(2005);Abdulagatov and Azizov(2006).Particularly,there is little in the literature on the effect of temperature on the rheo-logical behaviour of nanoﬂuids.Clearly,there is a gap in the current rheological literature for this type ofﬂuids.Furthermore,recent work has shown that the thermal behaviour of nanoﬂuids correlates well with their rheological behaviour(Prasher et al.2006a, b;Chen et al.2007a;Abdulagatov and Azizov2006). In a recent study,we investigated systemically the rheological behaviour of ethylene glycol(EG)based spherical TiO2nanoﬂuids(Chen et al.2007b).The results show that the nanoﬂuids are Newtonian over a shear rate range of0.5–104s-1and the shear viscosity is a strong function of temperature,particle concentration and aggregation microstructure.This work is concerned about the rheological behaviour of EG based nanoﬂuids containing titanate nanotubes (TNT).The speciﬁc objectives of the work are to investigate the effects of particle shape,particle concentration and temperature on nanoﬂuids viscosity, and to understand the relationship between the rheo-logical behaviour and the effective thermal conductivity of nanoﬂuids.It is for theﬁrst time that the rheological behaviour of a highly viscous EG based TNT nanoﬂuids is investigated in a systematic manner.As will be seen later,the results of this work provide further evidence that the rheological measure-ments could provide information of particle structuring for predicting the effective thermal conductivity of nanoﬂuids.The EG-TNT nanoﬂuids used in this work were formulated by using the so-called two-step method with EG purchased from Alfa Aesar and TNT synthesized in our labs using a method described elsewhere(Bavykin et al.2004).The details of nanoﬂuids formulation can be found elsewhere(Wen and Ding2005;He et al.2007;Chen et al.2007b). The TNT particles have a diameter(b)of*10nm and a length(L)of*100nm,giving an aspect ratio of(r=L/b)of*10.To avoid complications in interpreting the experimental results,no dispersants/ surfactants were used in the formulation.The nanoﬂuids formulated were found stable for over 2months.The rheological behaviour of the nano-ﬂuids was measured by using a Bolin CVO rheometer (Malvern Instruments,UK)over a shear rate range of 0.03–3,000s-1,a nanoparticle mass concentration of w=0–8%,and a temperature range of20–60°C (293–333K).The nanoﬂuids were characterised for their size by using a Malvern Nanosizer(Malvern Instruments,UK)and a scanning electron microscope (SEM).The average effective particle diameter was found to be*260nm for all nanoﬂuids formulated. This size is much larger than the equivalent diameter of the primary nanoparticles due to aggregation;see later for more discussion.Note that the particle size characterisation was performed both before and after the rheological measurements and no detectable changes to particle size were found.Figure1shows the viscosity of pure EG and EG-TNT nanoﬂuids as a function of shear rate at 40°C.The results at other temperatures are similar.It can be seen that the EG-TNT nanoﬂuids exhibit highly shear-thinning behaviour particularly when the TNT concentration exceeds*2%.Such behaviour is different from the observed Newtonian behaviour of EG-TiO2nanoﬂuids containing spherical nanoparti-cles over similar shear rate range(Chen et al.2007b) where the base liquid,EG,is the same as that used in the current wok.The behaviour is similar to the observations of carbon nanotube nanoﬂuids(Ding et al.2006)and CuO nanorod nanoﬂuids(Kwak and Kim2005),although there are important differencesbetween them such as temperature dependence as will be discussed later.The shear-thinning behaviour of well-dispersed suspensions can be interpreted by the structuring of interacting particles(Doi and Edwards1978a,b and Larson1999).In a quiescent state,a rod-like particle has three types of motion due to Brownian diffusion: rotational(end-over-end)motion around the mid-point and translational motion in parallel or perpendicular to the long axis.For dilute suspensions with a number density,c,ranging between0and1/L3or volume fraction,u,ranging between0and1/r2),the average spacing between the particles is larger than the longest dimension of the rod,and zero shear viscosity can be approximated by gð0Þ%g0ð1þAÁcL3Þwith g0the base liquid viscosity and A,a numerical constant(Doi and Edwards1978a).For suspensions with 1/L3\c\1/bL2or1/r2\f/\1/r,the rod-like particles start to interact.The rotational motion is severely restricted,as well as the translational motion perpendicular to the long axis,and the zero shear viscosity can be estimated by gð0Þ%g0ð1þðBcL3Þ3Þ; with B a numerical constant(Doi and Edwards1978b). As a consequence,the zero shear viscosity can be much greater than the base liquid viscosity.The large viscosity is due to the rod-like shape effect and the viscosity is very sensitive to shear,which tends to align particles and hence the shear-thinning behaviour as shown in Fig.1.Note that the above mechanism can give a qualitative explanation for the experimental observations at low-shear rates and the shear-thinning behaviour as shown in Fig.1,it does not explain the high-shear viscosity of the nanoﬂuids,which will be discussed later.It should also be noted that the criteria for classifying nanoﬂuids given above need to be modiﬁed due to the presence of aggregates;see later for more discussion.Figure2shows the shear viscosity of4.0%EG-TNT nanoﬂuids as a function of shear rate at different temperatures.The results under other concentrations are similar.It can be seen that the temperature has a very strong effect on the rheological behaviour of nanoﬂuids with higher temperatures giving stronger shear thinning.For shear rates below*10s-1,the shear viscosity increases with increasing temperature, whereas the trend is reversed when the shear rate is above*10s-1.As mentioned above,this behaviour was not observed for carbon nanotube(Ding et al. 2006)and CuO nanorod(Kwak and Kim2005)nanoﬂuids and we have not seen reports on such behaviour for nanoﬂuids in the literature;see later for more discussion on the underlying mechanisms. Figure2also shows that the strongest shear thinning occurs at40–60°C,whereas very weak-shear thinning takes places at20–30°C.It is also noted that the shear viscosity of nanoﬂuids at all temperatures investigated approaches a constant at high-shear rates.If the high-shear viscosity is plotted against temperature,Fig.3is obtained where the shear rate corresponding to the high-shear viscosity is taken as *2,000s-1.An inspection of all the data indicates that theyﬁt the following equation very well:ln g¼AþBÂ1000=TþCðÞð1Þwhere g is the shear viscosity(mPaÁs),T is the absolute temperature(K),and A,B and C areconstants given in Table1.Equation(1)takes a similar format as that widely used for liquid viscosity (Bird et al.2002)and for EG based nanoﬂuids containing spherical particles(Chen et al.2007b).If the measured high-shear viscosity is normalized with respect to the shear viscosity of the base liquid, the relative increaseðg i¼ðgÀg0Þ=g0Þof the high-shear viscosity is found to be only a function of concentration but independent of temperature over the temperature range investigated in this work.The relative increments in the shear viscosities of nano-ﬂuids containing0.5%,1.0%,2.0%,4.0%and8.0% particles are 3.30%,7.00%,16.22%,26.34%and 70.96%,respectively.Similar temperature indepen-dence of the shear viscosity was also observed for EG-TiO2and water-TiO2nanoﬂuids containing spherical nanoparticles(Chen et al.2007b).The experimentally observed temperature depen-dence can be interpreted as follows.Given the base liquid and nanoparticles,the functional dependence of viscosity on shear rate is determined by the relative importance of the Brownian diffusion and convection effects.At temperatures below*30°C,the contribu-tion from the Brownian diffusion is weak due to high-base liquid viscosity.As a consequence,the shear dependence of the suspension is weak(Fig.2).The contribution from the Brownian diffusion becomes increasingly important with increasing temperature particularly above40°C due to the exponential dependence of the base liquid viscosity on temperature (Fig.3).At very high-shear rates,the Brownian diffusion plays a negligible role in comparison with the convective contribution and hence independent of the high-shear viscosity on the temperature.We now start to examine if the classical theories for the high-shear viscosity predict the experimental measurements(note that there is a lack of adequate theories for predicting the low shear viscosity).Figure4shows the shear viscosity increment as a function of nanoparticle volume concentration together with the predictions by the following Brenner &Condiff Equation for dilute suspensions containing large aspect ratio rod-like particles(Brenner and Condiff1974):g¼g01þg½ uþO u2ÀÁÀÁð2Þwhere the intrinsic viscosity,½g ;for high-shear rates has the following form(Goodwin and Hughes2000):½g ¼0:312rln2rÀ1:5þ2À0:5ln2rÀ1:5À1:872rð3ÞAlso included in Fig.4are the data for EG-TiO2 nanoﬂuids with spherical nanoparticles(Chen et al. 2007b)and predictions by the Einstein Equation (Einstein1906,1911)for dilute non-interacting suspensions of spherical particles,g¼g01þ2:5uðÞ: It can be seen that both the Einstein and Brenner& Condiff equations greatly underpredict the measured data for the EG-TNT nanoﬂuids.The high-shear viscosity of EG-TNT nanoﬂuids is much higher than that of the EG-TiO2nanoﬂuids containing spherical nanoparticles,indicating a strong particle shape effect on the shear viscosity of nanoﬂuids.Although the shear-thinning behaviour of the nanoﬂuids could be partially attributed to the structuring of interacting rod-like particles,the large deviation between the measured high-shear viscosity and the predicted ones by the Brenner&Condiff equation cannot fully be interpreted.In the following,an attempt is made to explain the experimental observations from the viewpoint of aggregation of nanaoparticles,which have been shown to play a key role in thermal behaviour of nanoﬂuids in recent studies(Wang et al. 2003;Xuan et al.2003;Nan et al.1997;Prasher et al. 2006a,b;Keblinski et al.2005).Such an approach is also supported by the SEM and dynamic lightTable1Empirical constants for Eq.(1)a Maximum discrepancies;b Minimum discrepancies Concentration(wt%)A B C MaxD a(%)MinD b(%)0.0-3.21140.86973-154.570.62-1.440.5-3.42790.94425-148.490.93-0.471.0-2.94780.81435-159.14 1.11-0.692.0-2.2930.65293-174.57 1.64-0.694.0-2.63750.7574-165.820.99-0.948.0-2.73140.93156-145.010.88-1.57scattering analyses,which,as mentioned before, show clear evidence of particle aggregation.According to the modiﬁed Krieger-Dougherty equation(Goodwin and Hughes2000;Wang et al. 2003;Xuan et al.2003;Nan et al.1997),the relative viscosity of nanoﬂuids,g r,is given as:g r¼1Àu a=u mðÞÀ½g u mð4Þwhere u m is the maximum concentration at which the ﬂow can occur and u a is the effective volume fraction of aggregates given by u a¼u=u ma with u ma the maximum packing fraction of aggregates.As aggre-gates do not have constant packing throughout the structure,the packing density is assumed to change with radial position according to the power law with a constant index(D).As a result,u a is given as u a¼uða a=aÞ3ÀD;with a a and a,the effective radii of aggregates and primary nanoparticles,respectively. The term D is also referred as the fractal index meaning the extent of changes in the packing fraction from the centre to the edge of the aggregates.Typical values of D are given in normal textbook as D= 1.8–2.5for diffusion limited aggregation(DLA)and D=2.0–2.2for reaction limited aggregation(RLA); see for example Goodwin and Hughes(2000).For nanoﬂuids containing spherical nanoparticles,the value of D has been shown experimentally and numerically to be between1.6and1.8(Wang et al. 2003,Xuan et al.2003)and between1.8and2.3, respectively(Waite et al.2001).A typical value of 1.8is suggested for nanoﬂuids made of spherical nanoparticles(Prasher et al.2006a,b).However,little research has been found on the fractal index for nanoﬂuids containing rod-like nanoparticles.The colloid science literature suggests a fractal index of 1.5–2.45for colloidal suspensions depending on the type of aggregation,chemistry environment,particle size and shape and shearﬂow conditions(Haas et al. 1993;Mohraz et al.2004;Hobbie and Fry2006; Micali et al.2006;Lin et al.2007).In a recent study, Mohraz et al.(2004)investigated the effect of monomer geometry on the fractal structure of colloi-dal rod aggregates.They found that the fractal index is a non-linear function of the monomer aspect ratio with the D increasing from*1.80to*2.3when the aspect ratio of the rod-like nanoparticles increases from1.0to30.6.Based on the above,a value of D=2.1is taken for nanoﬂuids used in this work (Mohraz et al.2004,Lin et al.2007).Although the fractal model may appear to simplify the complexity of microstructures in aggregating systems containing rod-like particles,excellent agreement between the model prediction and experimental measurements exists when a a/a=9.46;see Fig.4.Here the aggregates are assumed to formﬂow units of an ellipsoidal shape with an effective aspect ratio of r a¼L a=b a;where L a and b a are the effective length and diameter,respectively.In the calculation,a typical value of u m of0.3is taken(Barnes et al.1989),and the intrinsic viscosity[g]is calculated by Eq.(3).It is to be noted that the aggregate size thatﬁts well to the rheological data(Fig.4)is consistent with the particle size analyses using both the SEM and the Malvern Nanosizer.A comparison between the EG-TNT data (a a/a=9.46,D=2.1,u m=0.30)and the EG-TiO2 data(a a/a=3.34,D=1.8,u m=0.605)(Chen et al. 2007b)in Fig.4suggests that the larger aggregate size in TNT nanoﬂuids be an important factor responsible for the stronger shear-thinning behaviour and higher shear viscosity of TNT nanoﬂuids.An inspection of Eq.(4)indicates that the effec-tive volume fraction u a u a¼u a a=aðÞ3ÀDis much higher than the actual volume fraction(u).This leads to the experimentally observed high-shear viscosity even for very dilute nanoﬂuids,according to the classiﬁcation discussed before.As a consequence,the demarcations deﬁning the dilute and semi-concen-trated dispersions should be changed by using the effective volume fraction.The model discussed above can also provide a macroscopic explanation for the temperature indepen-dence of the high-shear viscosity.From Eq.(4),one can see that the relative high-shear viscosity depends on three parameters,the maximum volume fraction, u m,the effective volume fraction,u a and the intrinsic viscosity,[g].For a given nanoﬂuid at a temperature not far from the ambient temperature,the three parameters are independent of temperature and hence the little temperature dependence of the relative shear viscosity.Microscopically,as explained before,the temperature-independent behaviour is due to negligi-ble Brownian diffusion compared with convection in high-shearﬂows.To further illustrate if the proposed aggregation mechanism is adequate,it is used to predict the effective thermal conductivity of the nanoﬂuids by using the following conventional Hamilton–Crosser model(H–C model)(Hamilton and Crosser1962):k=k0¼k pþðnÀ1Þk0ÀðnÀ1Þuðk0Àk pÞk pþðnÀ1Þk0þuðk0Àk pÞð5Þwhere k and k0are,respectively,the thermal conductivities of nanoﬂuids and base liquid,n is the shape factor given by n=3/w with w the surface area based sphericity.For TNT used in this work,the sphericity w is estimated as0.6(Hamilton and Crosser1962).For suspensions of aggregates,the above equation takes the following form:k=k0¼k aþðnÀ1Þk0ÀðnÀ1Þu aðk0Àk aÞa0a0að6Þwhere k a is the thermal conductivity of aggregates.To calculate k a,Eq.(6)is combined with the following Nan’s model(Nan et al.2003)for randomly dispersed nanotube-based composites:k a=k0¼3þu in½2b xð1ÀL xÞþb zð1ÀL zÞ3Àu in½2b x L xþb z L zð7Þwhere/in is the solid volume fraction of aggregates, b x¼ðk xÀk0Þ=½k mþL xðk tÀk mÞ and b z¼ðk zÀk0Þ=½k mþL zðk tÀk mÞ with k x,k m and k t being the thermal conductivities of nanotubes along trans-verse and longitudinal directions and isotropic thermal conductivity of the nanotube,respectively. In this work,k x,k m and k t are taken the same value as k p for aﬁrst order of approximation due to lack of experimental data,and L x and L z are geometrical factors dependent on the nanotube aspect ratio given by L x¼0:5r2=ðr2À1ÞÀ0:5r coshÀ1r=ðr2À1Þ3=2 and L z¼1À2L x:Figure5shows the experimental results together with predictions by the original H–C model(Eq.5) and revised H–C model(Eq.6).Here the experiment data were obtained using a KD2thermal property meter(Labcell,UK)(Murshed et al.2005;Chen et al. 2008).One can see that the measured thermal conductivity is much higher than the prediction by the conventional H–C model(Eq.5),whereas the modiﬁed H–C model taking into account the effect of aggregation(Eq.6)agrees very well with the exper-imental data.The above results suggest that nanoparticle aggregates play a key role in the enhancement of thermal conductivity of nanoﬂuids. The results also suggest that one could use the rheology data,which contain information of particle structuring in suspensions,for the effective thermal conductivity prediction.In summary,we have shown that EG-TNT nano-ﬂuids are non-Newtonian exhibiting shear-thinning behaviour over20–60°C and a particle mass concen-tration range of0–8%,in contrast to the Newtonian behaviour for EG-TiO2nanoﬂuids containing spher-ical particles.The non-Newtonian shear-thinning behaviour becomes stronger at higher temperatures or higher concentrations.For a given particle concen-tration,there exists a certain shear rate(e.g.*10s-1 for4wt%)below which the viscosity increases with increasing temperature,whereas the reverse occurs above such a shear rate.The normalised high-shearviscosity with respect to the base liquid viscosity, however,is found to be independent of temperature. These observations have not been reported in the literature for nanoﬂuids.Further analyses suggest that the temperature effects are due to the shear-depen-dence of the relative contributions to the viscosity of the Brownian diffusion and convection.The analyses also suggest that a combination of particle aggregation and particle shape effects is the mechanism for the observed high-shear rheological behaviour,which is supported not only by the particle size measurements but also by the thermal conductivity measurements and analyses using a combination of the H–C and Nan’s models.The results of this work also indicate that one could use the information of aggregation from the rheological experiments for predicting the effec-tive thermal conductivity of nanoﬂuids. 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Preliminary version

How the environment determines the efficiency of banks: acomparison between French and Spanish banking industry*Michel DietschUniversité Robert Schuman de Strasbourg, FranceAna Lozano VivasUniversidad de Málaga, SpainPreliminary version(September, 1996)*The research was supported by CNRS and DGICYT into the research program with reference PFECS95-0005.1. IntroductionTo understand the process of financial integration and convergence in Europe, it is necessary to know more about the competitiveness and the efficiency of banks in different European countries. However, cross-countries comparisons have to take into account the potential differences coming from some country-specific aspects of the banking technology, on one hand, and from the environmental and regulatory conditions, on the other hand. In particular, the economic environment are likely to differ significantly across countries and these differences could induce important differences of bank efficiency through different channels. For instance, differences of the income per capita, or differences of the densitydifferences in the nature of the of population across countries could produce significanthousehold’s demand for banking products and services.In this paper, we focus on two countries, France and Spain, and we try to deepen the analysis of the influence of the environment conditions on the cost efficiency of the French and Spanish banking industries. As pointed out by Berger and Humphrey (1996), this issue is not addressed in the international banking efficiency literature. From our point of view, cross-country comparison of efficiency requires to define properly a common frontier which incorporates the country-specific environmental conditions. Moreover, the integration of environmental variables in the analysis would allow to verify the degree of similarity between banking technology.Three categories of environmental variables are taken into account: the main macroeconomic which determine the banking products demand characteristics conditions, the structure and regulation of the banking industry, and the accessibility of banking services.Our results suggest that, before the introduction of environmental variables, the cost efficiency scores of Spanish banks were quite low, compared to those of the French banks. However, when the environmental variables were included in the model, the differences between the two countries banking industries reduced significantly. So, our resultsdemonstrate that the environmental variables appear to play a significant role in the explanation of the different efficiency scores between the two countries. More precisely, our results show that the Spanish banks seem to suffer excess costs, or structural disadvantages, in order to adjust to some environmental compared to French banks, such as the lower density of population, the lower income level of their customers or the lower rate of financial intermediation.A brief survey of the previous literature about cross-country comparisons of efficiency is presented in Section 2. The methodology for evaluating the cross-country efficiency when the particular environmental conditions of each country are taken in account is presented in Section 3. The data and the specification of inputs, outputs and environmental variables are described in Section 4. Section 5 presents the empirical results, and, finally, we provide some concluding remarks in Section 6.2. Previous literature in international comparison of banking efficiencyIn anticipation of the expected lowering of barriers to competition among financial institutions within the European Monetary Union (EMU), many EMU countries have recently experienced consolidation of their domestic banking industry. One reason for this consolidation is the belief that larger banks will be better able to adjust to the needs of the customers when they will be allowed to set up branches in any other country, subject only to the regulations of their home country. As domestic markets become more competitive, current differences in costs and productive efficiency among the banking industries of EMU countries will largely determine each country banking structure and future competitive viability. Thus, it is important to know how different or similar are current banking costsand productive efficiency between countries in order to predict increase in cross-border competition.There appears to be only six studies in the efficiency the effects of the expected literature that attempts todetermine and compare banking performances differences across-countries. Four of them3used nonparametric approaches while two used parametric approaches. In Berg, Forsund, Hjalmarson, and Suominen (1993), DEA analysis were relied upon to capture the differences in efficiency between Norway, Sweden, and Finland, first by defining separate frontiers for each country and comparing the countries pairwise based on each country’s frontier; and then defining a “common” frontier for doing the comparison among countries. Berg, Bukh and Forsund (1995) follow up the study by adding Denmark to the countries sample. The same four countries were investigated in Bergendahl (1995), using mixed optimal strategy for defining the efficient frontier.Fecher and Pestieau (1993) and Pastor, Perez, and Quesada (1995) applied DFA and DEA analysis to 11 OECD countries and 8 developed countries, respectively. The two studies pooled the cross-country data in order to define a common frontier. The former study found reverse results to these obtained by the Berg and al., and Bukh and al. studies taking the same set of countries.1Allen and Rai (1996) by using DFA and SFA carry out a systematic comparison of X-inefficiency measures across 15 developed countries distinguished by different regulatory environments. To do so, the countries were classified, previously, into two groups --universal and separated banking countries, respectively--delineated by their regulatory environment. Universal banking countries permit the functional integration of commercial and investment banking while separated banking countries do not. Once the inefficiency levels of those groups of banks were measured, the regularities in the inefficiency measures were investigated by regressing the firm specific inefficiency measures against various bank and market characteristics.The main caveat of these cross-country studies is that the common frontier is built under the belief that the differences in efficiency across countries only come from1See Berger and Humphrey (1996) for giving the details of the methodologies and results obtained on those studies.bank managerial decisions.2 That is, they are assuming that the mean difference in efficiency is located in differences of technologies. However, it is possible that the underlying technologies of the banking services productions in Europe and other developed countries are quite similar. Thus, the differences in efficiency across countries have to take into account the way in which banking services are produced. This production process is determined by country-specific differences—that are almost always excluded from cost and efficiency analyses—and not only by technology differences. Just as different relative prices of capital and labor inputs will result in different intensity of the use of these inputs in the production process, if the bank minimize costs and if the technology is constant, different national environments will result in different observed inputs, liabilities, and assets mixes and number of branches, again if the technology for producing banking services is constant. If the country-specific variables are an important factor in the explanation of the efficiency differences, then the frontier we obtain if we neglect this factor will generate an overestimation of the inefficiency levels.3If the regulatory and economic environments faced by financial institutions are likely to differ importantly across countries, the cross-country comparisons of the preceding papers are difficult to interpret. It is because in these papers the specification of the common frontier is not correct due to the fact that they do not take into account the influence of the country-specific environmental variables that will justify the use of a common frontier in cross-country comparisons of efficiency.andHere, we propose to compare the cost efficiency of the banking industries in France Spain, introducing in the cost frontier estimations the appropriate environmental2Although Allen and Rai’s paper takes into account the regulatory environments in the distinctionbetween groups of countries in order to compare the inefficiency levels, they specified banks variables and not country variables in order to explain the differences in efficiency.3Pastor et al., 1995, did corrections on efficiency measures by introducing the services provided to customers by the branch network and the degree of solvency determined by the capital ratio. Although it is well known that adding a restriction when it is using DEA increases (or leaves unaltered) the efficiency of all and every bank in the sample, they found that the relative efficiency of the countries banks improved. So, the economic environment of each country is an important explanation of the inefficiencies differences across countries and their integration will permit to avoid that the choice of the technology base influences the results when a common technology base is used for comparisons between countries.variables, so that the cross countries comparisons of efficiency would not be determined by the technology of one of the countries. That is, our goal is to permit the proper comparison of banking efficiency across countries by using a global best-practice econometric frontier, from which the banks in each country would be compared against the same standard.3. MethodologyThe technology of the banks can be defined as the set of the specific methods that the banks use to combine financial and physical inputs in order to produce a certain amount of banking services, such as liquidity and payment services, portfolio services, loans services. Those methods are diversification, pooling of risk, financial information collection and evaluation, risk management, and so on.More or less, the methods used by banks are the same in large industrial countries. So, there is a presumption that the technology should be the same in countries like France and Spain. However, the environmental conditions faced by financial institutions are likely to differ importantly. For instance, the average level of wealth, and the saving behavior of economic agents could be different in countries like France and Spain. The differences in the taxation of saving products could persist across countries in Europe, even if banks could now supply the same products all around Europe. The bankruptcy loan is still different from one country to another, so that the efficiency of the loans contracts differs across countries, and so on.With the aim of addressing the deficiencies found in the methodology applied in the intercountry efficiency comparisons that exist in the literature, we propose here an alternative methodology. In this alternative methodology, the specific environmental conditions of each country play an important role in the definition and specification of the common frontier of different countries.(3)(4)In this model, C represents the total of operating and financial (interests) costs.6 The Yj(j=l,2,3) represent the banking products. The Pm (m=l,2,3) refer to the input prices.7 Smare the share of costs paid to input m.8The term lnx is the systematic error componentThe banking outputs and inputs used in this study are as result of following the value added approach of Berger and Humphrey (1992). In the value added approach, all items on both sides of the balance sheet may be identified as outputs or inputs depending on their contribution to the generation of bank value added. Accordingly, we specified three variable outputs: loans (composed of the value of home loans and other loans), produced deposits (the sum of demand, saving, and time deposits), and other productive assets (the sum of all existing deposits with banks, short-term investments, and other investments). Prices for three variable inputs were also specified: labor, physical capital, and deposits (capturing the interest cost of deposits).The prices of inputs were computed by using the data of the banks themselves. For6That assumes that the banks try to minimize total costs and not only to minimize operating costs.7The definition of the estimated common cost frontier corresponds to the equation system (3)-(4), where the equation (3) contains as additional dependent variables the vector of country-specific variables pointed in the equation (2).8The share equations sum to one, so the physical capital share equation was omitted from the estimation.9Standard symetry and input prices homogeneity constraints are imposed on the total cost function (3).instance, the price of labor was estimated by using the information relative to the wages and taxes associated to the use of labor as they appeared in the banks accounts. Consequently, because we used the prices paid by bank for each factor of production, inefficiencies associated with overpayments to real or financial factors can not be evaluated by our approach. That could be a source of underestimation of the inefficiencies for banks paying factors at higher prices than the market prices.To compute inefficiencies by using DFA the estimate of inefficiency for each firm in a panel data set is determined as the difference between the average residual of each firm and the average residual of the firm on the frontier. That is, the average of the annualfor that bank, residuals for each bank i is computed and it served as an estimate of lnxiaverage residual of each bank i is used in the computation of X-efficiency. The efficiency score is given by the following equation:average cost residual which is assumed to be the completely efficient bank. Therefore, X-EFF is an estimate of the ratio of predicted costs for the most efficient bank to predicted costs for any bank. It is just like measuring X-efficiency by the ratio of predicted costs for the most efficient bank to predicted costs for each bank. Nevertheless, this measure ofother fully during the period. As noted by Berger (1993), this error is likely to be larger for banks near the extremes of the average residual. These banks may have experienced good (bad) luck over the entire period. Consequently, the minimum average residual, which serves here as a benchmark for the calculus of the X-efficiency, could be overestimated. To treat this problem, we have computed truncated measures of X-efficiency, where the value of average residual of the qth ((1-q)th) quantile was given to each observation for which the value of the average residual is below (above) the qth ((1-q)th) quantile value. We have used three values of q: 1%, 5%, and 25%.4. The Data and VariablesData.The data are annual accounting data over the 1988-1992 period for commercial and savings banks10 in France and Spain. It is important to emphasize that, in each country, banks are competing in the same markets and for the same customers. They have in each country quite similar access to the capital markets. In Spain and France, financial innovation and deregulation that generated an increase of competition in the banking industry appeared during the mid-eighties.11Therefore, the period of this study was a period of rapid technological changes in the production of financial and banking services during which the banks had to make strategic decisions to adjust to the new environment and the new competition. In particular, the banks began to reduce the number of employees and tried to adjust to the new environment in substituting capital for labor, specially in France.Only banks that were in existence for all 5 years were kept in the sample. The final sample used in this study contains 223 French banks and 101 Spanish banks12.Variable outputs and inputs.Table 1 presents the average values of bank outputs and inputs prices (converted in U.S.dollars)13 over the period 1988-1992 in each country. We observe that the average10By the First and Second Banking European Directives, these three categories of banks are now submitted to the same regulation.11During these years, new short-term securities were introduced, money market was modernized and it was left open to non-financial firms, new derivatives markets were created, interest rate controls were abolished and, finally, capital controls were suppressed.12Data come from official sources: Anuario de la Confederación de Cajas de Ahorros y del Consejo Superior Bancario, and Commission Bancaire. For the purpose of this study, the three French largest banks were excluded of the French sample, as their size would dominate the scale and distort the estimations. The smallest banks and the foreign banks were also excluded from the French and Spanish samples.13All variables initially measured in domestic currencies -including outputs, inputs prices or environmental variables - were converted into a common currency, following the purchasing power parity hypothesis. Here, we chose the U.S. dollar.size of the total balance sheet and the loans portfolio are very similar. This is due to the fact that our sample contains a lot of regional medium-sized banks. However, the average size of deposits differ across countries. One reason is that in France the time deposits interest rate regulation created an incentive in favor of other liquid investments, such as investments in mutual funds and money market deposits (the so-called OPCVM). So, French banks have to substitute money markets liabilities and bonds to time deposits in order to finance loans.The prices of inputs differ from one country to the other. In particular, we observe that both the labor price and the physical capital price are higher in France. This is mainly the consequence of the differences in the structure and regulation of the labor market and the real estate markets. However, due to the increase of competition in the deposits markets in Spain, the average cost of bank liabilities is higher in this country over the period. That is part of the explanation of the difference in total costs. Indeed, financial costs represent more than two third of total banking costs in Spain.Environmental variables.The environmental variables selected and used in order to identify the common frontier are macroeconomic variables as well as variables which explain the peculiar features of each country banking industry, such as regulatory conditions, banking structure and accessibility of banking services. We categorised those variables in three groups (Table 2). The first group is called “Main conditions”and includes a measure of the density of population, the income per capita, and the density of demand of each country. These indicators describe the main conditions in which banks exert their activities. The density of population is measured by the ratio of inhabitants per square kilometer. We assume that banking services supply in areas of low population density would generate higher banking costs, and at the same time would impede banks to obtain high efficiency levels. On the other hand, the income per capita of a country--measured as the ratio of Gross National Product per number of inhabitants--affects numerous factors related to the demand and supply for deposits and loans. Countries with higher income per capita are expected to have a banking system that operates in a mature environment resulting in more competitive interest rates, profit margins and efficiency levels. Finally, the density of demand, measured by the ratio of deposits by square kilometer,is assumed to be a relevant feature determining efficiency. Banks which operate in markets with a lower density of demand would likely incur higher expenses, ceteris paribus.The second category of environmental variables is called “Bank structure and regulation” and contains variables describing the structure and regulation of the banking industry in each country such as the degree of concentration, the average capital ratio, and the intermediation ratio of the banking industry of each country. The concentration of the banking industry is measured by the Herfindahl index defined as the sum of squared market shares of assets of all banks in each country. In analyzing market structure we consider each country to be a market. Since banks operate exclusively throughout each country and since entry has until recently been restricted by national borders, a national market is appropriate. We expect that higher concentration would be associated with higher costs as well as lower costs. If higher concentration is a result of the market power, concentrationand costs go in the same way. However, it could be possible that higher concentration would be associated with lower costs if the concentration is the result of either superior management or greater efficiency of the production processes. As proxy of regulatory conditions we define the average capital ratio, measured by equity capital as a fraction of total assets. Usually, lower capital ratio imply higher risk taking and greater leverage which could result in increased borrowing costs, leading to lower efficiency levels. The last variable included into the second group of environmental variables is the intermediation ratio, defined as the ratio of total deposits over total loans. By using this variable, it is possible to capture the differences between the two domestic banking industries in terms of their ability to convert deposits into loans. As higher the intermediation ratio is, as higher would be the banking industry costs.Finally, the third category of environmental variables refers to the accessibility of the banking services for customers, measured by the number of branches by square kilometer. This variable is used as a measure of branch density that takes in account the space dimension for each national market. It is also a good indicator of the potential overcapacity of the branch network in each country. This variable could measure the degree of competition in the banking market. Indeed, before the banking deregulation of the mid-eighties, the competition between banks took mainly the form of a non-price competition and during that period the banks compete by increasing their number of branches. This non-price competition strategy appeared in France as well as in Spain.particular, the capital ratio is very different. This difference could be due to the fact that during the period of our study—which precede the effective introduction of the capital ratio international regulation—the solvency constraints imposed by the Spanish banking authorities obliged Spanish banks to maintain a higher level of capital ratio, compared to that of French banks. Another difference between the two domestic banking industries come from the fact that the intermediation ratio is higher in Spain than in France. That means that Spanish banks have to collect a higher level of costly deposits (in terms of operating costs) in order to lend the same amount of loans. In these conditions, it seems more expensive to exert banking activities in Spain than in France, ceteris paribus. However, the degree of concentration of the banking industry is quite the same in the two countries.Finally, the accessibility of banking services is higher in Spain than in France. That is consistent with the previous observation concerning the density of population and the amount of deposits by km2.So, the conditions in which Spanish banks operate seem to produce higher level of operating costs. However, again, we should emphasize the fact that the number of branches could be an indicator of the competition imperfectness in banking markets.5. Empirical ResultsOur empirical exercise starts with the measurement of efficiency scores of each French and Spanish banks from its own national frontier—that is, assuming that the technology used for the banks in each country is different. These results are summarized in Table 3. They show that on average the level of efficiency is the same in France and Spain. This average efficiency level is around 88% over the 1988-1992 period. In other words, French and Spanish banks are on average equally efficient in their respective countries. However, given these results, it is not possible to predict what will happen if the banks would decide to operate in the other country. That is, it is not possible to conclude whether the French or Spanish banks will reach the same efficiency level in the othercountry than they get in their own country. To answer this question, we have to measure efficiency scores from a common frontier, and for that purpose we defined the common frontier by following the traditional approach. We measured the efficiency levels of each country banks from a common frontier by pooling the data set of the banks of the two countries, Table 4. The results show that while the average efficiency level of the French banks appear to be 58%, the Spanish banks are operating with an average efficiency level of only 9%. This surprising result is in accordance with our assumption that if the country-specific variables are an important factor in the then the frontier we build while neglecting this the inefficiency levels.explanation of the efficiency differences,factor will generate an overestimation ofintroduce those variables in the common frontier, the efficiency levels improve significantly in both countries.The influence of the environmental variables seems in general to conform to the expectations (Table 6). All the coefficients on the environmental variables in the estimation of the cost function are significant at the 1% level of confidence. That proves the effectiveness of the role of such variables. First, we consider the role of the “main conditions” or macroeconomic conditions. Contrary to the expectations, the sign of the coefficient of the density of population variable is positive. That shows that a higher density contributes to increase banking costs, instead of to decrease them, as expected. The reason could come in part from the characteristics of the banking competition. In particular, if banks compete by opening more branches, for strategic reasons, that could create an inflation of the bank operating costs. Moreover, in this form of non price competition, banks should have to open branches in large cities where the real estate is most costly and the salaries higher. The sign of the income per capita is also positive, which shows that the higher is the development level of the economy, the higher are the operating and financial costs that the banks suffer when supplying a given level of services. The sign of the density of the demand is negative. The explanation could be that it is likely more costly to give satisfaction to a less important demand of banking services, because that demand is less informed and less concentrated. Another argument is that a more important demand permits banks to extract higher scale and scope economies.Second, we consider the variables describing the structure and competition of the domestic banking industry. We observe that the banking costs are increasing with the degree of imperfection of the banking competition. In particular, the sign of the Herfindhal index variable is positive. If we take that index as a measure of the market power of banks, the positive sign tends to demonstrate that higher market power induces banks to spend more in staff or personal expenses. On the other hand, the sign of the intermediation rate variable is positive, showing that a greater amount of deposits by unit of loans induce logically an increase of banking costs. And finally, the sign of the capital ratio is negative showing that it is less costly to produce banking services if the banks are better capitalized. As mentioned before, one explanation could come from the existence of a negative relationship between bank risk and bank borrowing costs.Third, we consider the accessibility of the banking products for the customers. The observation shows that the sign of this variable is positive. The lower the density of bank。

2006_Differential Privacy

Diﬀerential PrivacyCynthia DworkMicrosoft Researchdwork@Abstract.In1977Dalenius articulated a desideratum for statisticaldatabases:nothing about an individual should be learnable from thedatabase that cannot be learned without access to the database.We givea general impossibility result showing that a formalization of Dalenius’goal along the lines of semantic security cannot be achieved.Contrary tointuition,a variant of the result threatens the privacy even of someonenot in the database.This state of aﬀairs suggests a new measure,dif-ferential privacy,which,intuitively,captures the increased risk to one’sprivacy incurred by participating in a database.The techniques devel-oped in a sequence of papers[8,13,3],culminating in those describedin[12],can achieve any desired level of privacy under this measure.Inmany cases,extremely accurate information about the database can beprovided while simultaneously ensuring very high levels of privacy.1IntroductionA statistic is a quantity computed from a sample.If a database is a repre-sentative sample of an underlying population,the goal of a privacy-preserving statistical database is to enable the user to learn properties of the population as a whole,while protecting the privacy of the individuals in the sample.The work discussed herein was originally motivated by exactly this problem:how to reveal useful information about the underlying population,as represented by the database,while preserving the privacy of individuals.Fortuitously,the techniques developed in[8,13,3]and particularly in[12]are so powerful as to broaden the scope of private data analysis beyond this orignal“representatitive”motivation,permitting privacy-preserving analysis of an object that is itself of intrinsic interest.For instance,the database may describe a concrete intercon-nection network–not a sample subnetwork–and we wish to reveal certain properties of the network without releasing information about individual edges or nodes.We therefore treat the more general problem of privacy-preserving analysis of data.A rigorous treatment of privacy requires deﬁnitions:What constitutes a fail-ure to preserve privacy?What is the power of the adversary whose goal it is to compromise privacy?What auxiliary information is available to the adversary (newspapers,medical studies,labor statistics)even without access to the data-base in question?Of course,utility also requires formal treatment,as releasing no information or only random noise clearly does not compromise privacy;we M.Bugliesi et al.(Eds.):ICALP2006,Part II,LNCS4052,pp.1–12,2006.c Springer-Verlag Berlin Heidelberg20062 C.Dworkwill return to this point later.However,in this work privacy is paramount:we willﬁrst deﬁne our privacy goals and then explore what utility can be achieved given that the privacy goals will be satisiﬁed1.A1977paper of Dalenius[6]articulated a desideratum that foreshadows for databases the notion of semantic security deﬁnedﬁve years later by Goldwasser and Micali for cryptosystems[15]:access to a statistical database should not enable one to learn anything about an individual that could not be learned without access2.We show this type of privacy cannot be achieved.The obstacle is in auxiliary information,that is,information available to the adversary other than from access to the statistical database,and the intuition behind the proof of impossibility is captured by the following example.Suppose one’s exact height were considered a highly sensitive piece of information,and that revealing the exact height of an individual were a privacy breach.Assume that the database yields the average heights of women of diﬀerent nationalities.An adversary who has access to the statistical database and the auxiliary information“Terry Gross is two inches shorter than the average Lithuanian woman”learns Terry Gross’height,while anyone learning only the auxiliary information,without access to the average heights,learns relatively little.There are two remarkable aspects to the impossibility result:(1)it applies regardless of whether or not Terry Gross is in the database and(2)Dalenius’goal,formalized as a relaxed version of semantic security,cannot be achieved, while semantic security for cryptosystems can be achieved.Theﬁrst of these leads naturally to a new approach to formulating privacy goals:the risk to one’s privacy,or in general,any type of risk,as the risk of being denied insurance,should not substantially increase as a result of participating in a statistical database.This is captured by diﬀerential privacy.The discrepancy the possibility of achieving(something like)seman-tic security in our setting and in the cryptographic one arises from the utility requirement.Our adversary is analagous to the eavesdropper,while our user is analagous to the message recipient,and yet there is no decryption key to set them apart,they are one and the same.Very roughly,the database is designed to convey certain information.An auxiliary information generator knowing the data therefore knows much about what the user will learn from the database. This can be used to establish a shared secret with the adversary/user that is unavailable to anyone not having access to the database.In contrast,consider a cryptosystem and a pair of candidate messages,say,{0,1}.Knowing which message is to be encrypted gives one no information about the ciphertext;in-tuitively,the auxiliary information generator has“no idea”what ciphertext the eavesdropper will see.This is because by deﬁnition the ciphertext must have no utility to the eavesdropper.1In this respect the work on privacy diverges from the literature on secure function evaluation,where privacy is ensured only modulo the function to be computed:if the function is inherently disclosive then privacy is abandoned.2Semantic security against an eavesdropper says that nothing can be learned about a plaintext from the ciphertext that could not be learned without seeing the ciphertext.Diﬀerential Privacy3 In this paper we prove the impossibility result,deﬁne diﬀerential privacy,and observe that the interactive techniques developed in a sequence of papers[8, 13,3,12]can achieve any desired level of privacy under this measure.In many cases very high levels of privacy can be ensured while simultaneously providing extremely accurate information about the database.Related Work.There is an enormous literature on privacy in databases;we brieﬂy mention a fewﬁelds in which the work has been carried out.See[1]for a survey of many techniques developed prior to1989.By far the most extensive treatment of disclosure limitation is in the statistics community;for example,in1998the Journal of Oﬃcial Statistics devoted an entire issue to this question.This literature contains a wealth of privacy sup-portive techniques and investigations of their impact on the statistics of the data set.However,to our knowledge,rigorous deﬁnitions of privacy and modeling of the adversary are not features of this portion of the literature.Research in the theoretical computer science community in the late1970’s had very speciﬁc deﬁnitions of privacy compromise,or what the adversary must achieve to be considered successful(see,eg,[9]).The consequent privacy guaran-tees would today be deemed insuﬃciently general,as modern cryptography has shaped our understanding of the dangers of the leakage of partial information. Privacy in databases was also studied in the security community.Although the eﬀort seems to have been abandoned for over two decades,the work of Den-ning[7]is closest in spirit to the line of research recently pursued in[13,3,12].The work of Agrawal and Srikant[2]and the spectacular privacy compromises achieved by Sweeney[18]rekindled interest in the problem among computer scientists,particularly within the database community.Our own interest in the subject arose from conversations with the philosopher Helen Nissenbaum.2Private Data Analysis:The SettingThere are two natural models for privacy mechanisms:interactive and non-interactive.In the non-interactive setting the data collector,a trusted entity, publishes a“sanitized”version of the collected data;the literature uses terms such as“anonymization”and“de-identiﬁcation”.Traditionally,sanitization employs techniques such as data perturbation and sub-sampling,as well as re-moving well-known identiﬁers such as names,birthdates,and social security numbers.It may also include releasing various types of synopses and statistics. In the interactive setting the data collector,again trusted,provides an interface through which users may pose queries about the data,and get(possibly noisy) answers.Very powerful results for the interactive approach have been obtained([13, 3,12]and the present paper),while the non-interactive case has proven to be more diﬃcult,(see[14,4,5]),possibly due to the diﬃculty of supplying utility that has not yet been speciﬁed at the time the sanitization is carried out.This intuition is given some teeth in[12],which shows concrete separation results.4 C.Dwork3Impossibility of Absolute Disclosure PreventionThe impossibility result requires some notion of utility–after all,a mechanism that always outputs the empty string,or a purely random string,clearly preserves privacy3.Thinkingﬁrst about deterministic mechanisms,such as histograms or k-anonymizations[19],it is clear that for the mechanism to be useful its output should not be predictable by the user;in the case of randomized mechanisms the same is true,but the unpredictability must not stem only from random choices made by the mechanism.Intuitively,there should be a vector of questions(most of)whose answers should be learnable by a user,but whose answers are not in general known in advance.We will therefore posit a utility vector,denoted w. This is a binary vector of someﬁxed lengthκ(there is nothing special about the use of binary values).We can think of the utility vector as answers to questions about the data.A privacy breach for a database is described by a Turing machine C that takes as input a description of a distribution D on databases,a database DB drawn according to this distribution,and a string–the purported privacy breach–and outputs a single bit4.We will require thatC always halt.We say the adversary wins,with respect to C and for a given(D,DB)pair,if it produces a string s such that C(D,DB,s)accepts.Henceforth“with respect to C”will be implicit.An auxiliary information generator is a Turing machine that takes as input a description of the distribution D from which the database is drawn as well as the database DB itself,and outputs a string,z,of auxiliary information.This string is given both to the adversary and to a simulator.The simulator has no access of any kind to the database;the adversary has access to the database via the privacy mechanism.We model the adversary by a communicating Turing machine.The theorem below says that for any privacy mechanism San()and any distribution D sat-isfying certain technical conditions with respect to San(),there is always some particular piece of auxiliary information,z,so that z alone is useless to someone trying to win,while z in combination with access to the data through the pri-vacy mechanism permits the adversary to win with probability arbitrarily close to1.In addition to formalizing the entropy requirements on the utility vectors as discussed above,the technical conditions on the distribution say that learning the length of a privacy breach does not help one to guess a privacy breach. Theorem1.Fix any privacy mechanism San()and privacy breach decider C. There is an auxiliary information generator X and an adversary A such that for all distributions D satisfying Assumption3and for all adversary simulators A∗, Pr[A(D,San(D,DB),X(D,DB))wins]−Pr[A∗(D,X(D,DB))wins]≥ΔwhereΔis a suitably chosen(large)constant.The probability spaces are over choice of DB∈R D and the coinﬂips of San,X,A,and A∗.3Indeed the height example fails in these trivial cases,since it is only through the sanitization that the adversary learns the average height.4We are agnostic as to how a distribution D is given as input to a machine.Diﬀerential Privacy5 The distribution D completely captures any information that the adversary(and the simulator)has about the database,prior to seeing the output of the auxiliary information generator.For example,it may capture the fact that the rows in the database correspond to people owning at least two pets.Note that in the statement of the theorem all parties have access to D and may have a description of C hard-wired in;however,the adversary’s strategy does not use either of these.Strategy for X and A when all of w is learned from San(DB):To develop intuition weﬁrst describe,slightly informally,the strategy for the special case in which the adversary always learns all of the utility vector,w,from the privacy mechanism5.This is realistic,for example,when the sanitization produces a histogram,such as a table of the number of people in the database with given illnesses in each age decile,or a when the sanitizer chooses a random subsample of the rows in the database and reveals the average ages of patients in the subsample exhibiting various types of symptoms.This simpler case allows us to use a weaker version of Assumption3:Assumption2. 1.∀0<γ<1∃nγPr DB∈R D [|DB|>nγ]<γ;moreover nγis computable by a machine given D as input.2.There exists an such that both the following conditions hold:(a)Conditioned on any privacy breach of length ,the min-entropy of theutility vector is at least .(b)Every DB∈D has a privacy breach of length .3.Pr[B(D,San(DB))wins]≤μfor all interactive Turing machines B,whereμis a suitably small constant.The probability is taken over the coinﬂips ofB and the privacy mechanism San(),as well as the choice of DB∈R D. Intuitively,Part(2a)implies that we can extract bits of randomness from theutility vector,which can be used as a one-time pad to hide any privacy breach of the same length.(For the full proof,ie,when not necessarily all of w is learned by the adversary/user,we will need to strengthen Part(2a).)Let 0denote the leastsatisfying(both clauses of)Part2.We cannot assume that 0can be found in ﬁnite time;however,for any toleranceγlet nγbe as in Part1,so all but aγfraction of the support of D is strings of length at most nγ.For anyﬁxedγit ispossible toﬁnd an γ≤ 0such that γsatisﬁes both clauses of Assumption2(2) on all databases of length at most nγ.We can assume thatγis hard-wired intoall our machines,and that they all follow the same procedure for computing nγand γ.Thus,Part1allows the more powerful order of quantiﬁersd in the statement of the theorem;without it we would have to let A and A∗depend on D(by having hard-wired in).Finally,Part3is a nontriviality condition. The strategy for X and A is as follows.On input DB∈R D,X randomly chooses a privacy breach y for DB of length = γ,if one exists,which occurs with probability at least1−γ.It also computes the utility vector,w.Finally, it chooses a seed s and uses a strong randomness extractor to obtain from w 5Although this case is covered by the more general case,in which not all of w need be learned,it permits a simpler proof that exactly captures the height example.6 C.Dworkan -bit almost-uniformly distributed string r[16,17];that is,r=Ext(s,w), and the distribution on r is within statistical distance from U ,the uniform distribution on strings of length ,even given s and y.The auxiliary information will be z=(s,y⊕r).Since the adversary learns all of w,from s it can obtain r=Ext(s,w)and hence y.We next argue that A∗wins with probability(almost)bounded byμ, yielding a gap of at least1−(γ+μ+ ).Assumption2(3)implies that Pr[A∗(D)wins]≤μ.Let d denote the maxi-mum,over all y∈{0,1} ,of the probability,over choice of DB∈R D,that y is a privacy breach for DB.Since = γdoes not depend on DB,Assumption2(3) also implies that d ≤μ.By Assumption2(2a),even conditioned on y,the extracted r is(almost) uniformly chosen,independent of y,and hence so is y⊕r.Consequently,the probability that X produces z is essentially independent of y.Thus,the simula-tor’s probability of producing a privacy breach of length for the given database is bounded by d + ≤μ+ ,as it can generate simulated“auxiliary information”with a distribution within distance of the correct one.The more interesting case is when the sanitization does not necessarily reveal all of w;rather,the guarantee is only that it always reveal a vector w within Hamming distanceκ/c of w for constant c to be determined6.The diﬃculty with the previous approach is that if the privacy mechanism is randomized then the auxiliary information generator may not know which w is seen by the adversary. Thus,even given the seed s,the adversary may not be able to extract the same random pad from w that the auxiliary information generator extracted from w. This problem is solved using fuzzy extractors[10].Deﬁnition1.An(M,m, ,t, )fuzzy extractor is given by procedures (Gen,Rec).1.Gen is a randomized generation procedure.On input w∈M outputs an“extracted”string r∈{0,1} and a public string p.For any distribution W on M of min-entropy m,if(R,P)←Gen(W)then the distributions(R,P) and(U ,P)are within statistical distance .2.Rec is a deterministic reconstruction procedure allowing recovery of r=R(w)from the corresponding public string p=P(w)together with any vector w of distance at most t from w.That is,if(r,p)←Gen(w)and||w−w ||1≤t then Rec(w ,p)=r.In other words,r=R(w)looks uniform,even given p=P(w),and r=R(w) can be reconstructed from p=P(w)and any w suﬃciently close to w.We now strenthen Assumption2(2a)to say that the entropy of the source San(W)(vectors obtained by interacting with the sanitization mechanism,all of 6One could also consider privacy mechanisms that produce good approximations to the utility vector with a certain probability for the distribution D,where the proba-bility is taken over the choice of DB∈R D and the coins of the privacy mechanism.The theorem and proof hold mutatis mutandis.Diﬀerential Privacy7 distance at mostκ/c from the true utility vector)is high even conditioned onany privacy breach y of length and P=Gen(W).Assumption3.For some satisfying Assumption2(2b),for any privacy breachy∈{0,1} ,the min-entropy of(San(W)|y)is at least k+ ,where k is the lengthof the public strings p produced by the fuzzy extractor7.Strategy when w need not be fully learned:For a given database DB,let w bethe utility vector.This can be computed by X,who has access to the database. X simulates interaction with the privacy mechanism to determine a“valid”w close to w(within Hamming distanceκ/c).The auxiliary information generatorruns Gen(w ),obtaining(r=R(w ),p=P(w )).It computes nγand = γ(as above,only now satisfying Assumptions3and2(2b)for all DB∈D of length at most nγ),and uniformly chooses a privacy breach y of length γ,assuming one exists.It then sets z=(p,r⊕y).Let w be the version of w seen by the adversary.Clearly,assuming2κ/c≤tin Deﬁnition1,the adversary can reconstruct r.This is because since w and w are both withinκ/c of w they are within distance2κ/c of each other,and so w is within the“reconstruction radius”for any r←Gen(w ).Once the adversary has reconstructed r,obtaining y is immediate.Thus the adversary is able to produce a privacy breach with probability at least1−γ.It remains to analyze the probability with which the simulator,having access only to z but not to the privacy mechanism(and hence,not to any w close to w),produces a privacy breach.In the sequel,we let B denote the best machine,among all those with access to the given information,at producing producing a privacy breach(“winning”).By Assumption2(3),Pr[B(D,San(DB))wins]≤μ,where the probability istaken over the coin tosses of the privacy mechanism and the machine B,and the choice of DB∈R D.Since p=P(w )is computed from w ,which in turn is computable from San(DB),we havep1=Pr[B(D,p)wins]≤μwhere the probability space is now also over the choices made by Gen(),that is,the choice of p=P(w ).Now,let U denote the uniform distribution on -bit strings.Concatenating a random string u∈R U to p cannot help B to win,sop2=Pr[B(D,p,u)wins]=p1≤μwhere the probability space is now also over choice of u.For anyﬁxed string y∈{0,1} we have U =U ⊕y,so for all y∈{0,1} ,and in particular,for all privacy breaches y of DB,p3=Pr[B(D,p,u⊕y)wins]=p2≤μ.7A good fuzzy extractor“wastes”little of the entropy on the public string.Better fuzzy extractors are better for the adversary,since the attack requires bits of residual min-entropy after the public string has been generated.8 C.DworkLet W denote the distribution on utility vectors and let San(W)denote the distribution on the versions of the utility vectors learned by accessing the data-base through the privacy mechanism.Since the distributions(P,R)=Gen(W ), and(P,U )have distance at most ,it follows that for any y∈{0,1}p4=Pr[B(D,p,r⊕y)wins]≤p3+ ≤μ+ .Now,p4is an upper bound on the probability that the simulator wins,given D and the auxiliary information z=(p,r⊕y),soPr[A∗(D,z)wins]≤p4≤μ+ .An(M,m, ,t, )fuzzy extractor,where M is the distribution San(W)on utility vectors obtained from the privacy mechanism,m satisﬁes:for all -bit strings y which are privacy breaches for some database D∈DB,H∞(W |y)≥m; and t<κ/3,yields a gap of at least(1−γ)−(μ+ )=1−(γ+μ+ )between the winning probabilities of the adversary and the simulator.Setting Δ=1−(γ+μ+ )proves Theorem1.We remark that,unlike in the case of most applications of fuzzy extractors (see,in particular,[10,11]),in this proof we are not interested in hiding partial information about the source,in our case the approximate utility vectors W ,so we don’t care how much min-entropy is used up in generating p.We only require suﬃcient residual min-entropy for the generation of the random pad r.This is because an approximation to the utility vector revealed by the privacy mecha-nism is not itself disclosive;indeed it is by deﬁnition safe to release.Similarly,we don’t necessarily need to maximize the tolerance t,although if we have a richer class of fuzzy extractors the impossibility result applies to more relaxed privacy mechanisms(those that reveal worse approximations to the true utility vector).4Diﬀerential PrivacyAs noted in the example of Terry Gross’height,an auxiliary information gen-erator with information about someone not even in the database can cause a privacy breach to this person.In order to sidestep this issue we change from ab-solute guarantees about disclosures to relative ones:any given disclosure will be, within a small multiplicative factor,just as likely whether or not the individual participates in the database.As a consequence,there is a nominally increased risk to the individual in participating,and only nominal gain to be had by con-cealing or misrepresenting one’s data.Note that a bad disclosure can still occur, but our guarantee assures the individual that it will not be the presence of her data that causes it,nor could the disclosure be avoided through any action or inaction on the part of the user.Diﬀerential Privacy9 Deﬁnition2.A randomized function K gives -diﬀerential privacy if for all data sets D1and D2diﬀering on at most one element,and all S⊆Range(K),Pr[K(D1)∈S]≤exp( )×Pr[K(D2)∈S](1) A mechanism K satisfying this deﬁnition addresses concerns that any participant might have about the leakage of her personal information x:even if the partic-ipant removed her data from the data set,no outputs(and thus consequences of outputs)would become signiﬁcantly more or less likely.For example,if the database were to be consulted by an insurance provider before deciding whether or not to insure Terry Gross,then the presence or absence of Terry Gross in the database will not signiﬁcantly aﬀect her chance of receiving coverage.This deﬁnition extends to group privacy as well.A collection of c participants might be concerned that their collective data might leak information,even when a single participant’s does ing this deﬁnition,we can bound the dilation of any probability by at most exp( c),which may be tolerable for small c.Note that we speciﬁcally aim to disclose aggregate information about large groups,so we should expect privacy bounds to disintegrate with increasing group size.5Achieving Diﬀerential PrivacyWe now describe a concrete interactive privacy mechanism achieving -diﬀerential privacy8.The mechanism works by adding appropriately chosen random noise to the answer a=f(X),where f is the query function and X is the database;thus the query functions may operate on the entire database at once.It can be simple–eg,“Count the number of rows in the database satisfy-ing a given predicate”–or complex–eg,“Compute the median value for each column;if the Column1median exceeds the Column2median,then output a histogram of the numbers of points in the set S of orthants,else provide a histogram of the numbers of points in a diﬀerent set T of orthants.”Note that the complex query above(1)outputs a vector of values and(2)is an adaptively chosen sequence of two vector-valued queries,where the choice of second query depends on the true answer to theﬁrst query.Although complex, it is soley a function of the database.We handle such queries in Theorem4.The case of an adaptively chosen series of questions,in which subsequent queries depend on the reported answers to previous queries,is handled in Theorem5. For example,suppose the adversaryﬁrst poses the query“Compute the median of each column,”and receives in response noisy versions of the medians.Let M be the reported median for Column1(so M is the true median plus noise).The adversary may then pose the query:“If M exceeds the true median for Column1 (ie,if the added noise was positive),then...else...”This second query is a function not only of the database but also of the noise added by the privacy mechanism in responding to theﬁrst query;hence,it is adaptive to the behavior of the mechanism.8This mechanism was introduced in[12],where analagous results were obtained for the related notion of -indistinguishability.The proofs are essentially the same.10 C.Dwork5.1Exponential Noise and the L1-SensitivityWe will achieve -diﬀerential privacy by the addition of random noise whose magnitude is chosen as a function of the largest change a single participant could have on the output to the query function;we refer to this quantity as the sensitivity of the function9.Deﬁnition3.For f:D→R d,the L1-sensitivity of f isf(D1)−f(D2) 1(2)Δf=maxD1,D2for all D1,D2diﬀering in at most one element.For many types of queriesΔf will be quite small.In particular,the simple count-ing queries(“How many rows have property P?”)haveΔf≤1.Our techniques work best–ie,introduce the least noise–whenΔf is small.Note that sensitivity is a property of the function alone,and is independent of the database.The privacy mechanism,denoted K f for a query function f,computes f(X) and adds noise with a scaled symmetric exponential distribution with variance σ2(to be determined in Theorem4)in each component,described by the density functionPr[K f(X)=a]∝exp(− f(X)−a 1/σ)(3) This distribution has independent coordinates,each of which is an exponentially distributed random variable.The implementation of this mechanism thus simply adds symmetric exponential noise to each coordinate of f(X).Theorem4.For f:D→R d,the mechanism K f gives(Δf/σ)-diﬀerential privacy.Proof.Starting from(3),we apply the triangle inequality within the exponent, yielding for all possible responses rPr[K f(D1)=r]≤Pr[K f(D2)=r]×exp( f(D1)−f(D2) 1/σ).(4) The second term in this product is bounded by exp(Δf/σ),by the deﬁnition of Δf.Thus(1)holds for singleton sets S={a},and the theorem follows by a union bound.Theorem4describes a relationship betweenΔf,σ,and the privacy diﬀerential. To achieve -diﬀerential privacy,one must chooseσ≥ /Δf.The importance of choosing the noise as a function of the sensitivity of the entire complex query is made clear by the important case of histogram queries,in which the domain of data elements is partitioned into some number k of classes, such as the cells of a contingency table of gross shoe sales versus geographic 9It is unfortunate that the term sensitivity is overloaded in the context of privacy.We chose it in concurrence with sensitivity analysis.。

美国陪审团的一致裁决原则

美国陪审团的一致裁决原则：历史与当下关键词: 美国，陪审团，一致裁决原则内容提要: 陪审团的一致裁决原则起源于14世纪的英国，作为一项普通法的传统，它在美国确立后经历了一个联邦强制适用与各州选择适用并存这一局面被明确和强化的过程。

虽然饱受质疑，但是从一致裁决原则对陪审团司法工具价值和政治民主价值的发挥及对审判成本控制的影响这三个角度出发综合考虑，其在一定时间内还将继续存在下去。

“你为什么会认为他无罪？”“虽然你们11个都认为他有罪，但我想先和你们好好谈谈，否则我很难说服自己举手认同你们的观点，送这个男孩去死。

”[1]作为美国司法体系的核心组成部分，陪审团制度曾为其赢得了广泛的赞[2]。

陪审团审理案件时，在就相关情况进行充分的“秘密评议”[3]后，无论要做出有罪还是无罪裁决，均需首先在其内部达成一致意见，否则会导致无效审判（mistrial）的出现（此时陪审团相应地被称作“悬置陪审团”（hung ju-ry）—这就是美国陪审团的一致裁决原则[4]。

这项原则起源于英国，作为普通法的传统为美国所接受后，长期以来被视为一项“神圣不可侵犯的”[5]、“统治性的规则”[6]，并作为陪审团制度的“基石”[7]、裁决规则的“底线”[8]在美国联邦法院系统和州法院系统被严格遵行。

然而，随着一系列具有争议的陪审团裁决的出现[9]，美国民众对陪审团审判“不准确、不公正”的印象日益滋生，对其进行根本性改革的呼声也越来越高[10]。

在这种整体性的不满之中，指向一致裁决原则的自然也占有相当大的比重。

有学者认为这是一个“过时的传统”[11]，甚至认为它所带来的危害正是现在陪审团面临的“最严重的问题之一”[12]。

与民众的呼声和学界的议论相伴，在司法实践中，这一原则也已有所松动。

虽然在联邦层面，依然继续严格要求使用一致裁决，但是在各州，情况则发生了变化。

就刑事案件而言，路易斯安那州和俄勒冈州已经在州宪法中明确规定，除死刑案件外，其他案件允许非一致裁决。

24nm 64G eX3 (8LC) Data Sheet-pkg rev1-0

PR EL
Proprietary and Confidential
IM
IN
January 24, 2011
AR
Preliminary Version Rev 1.0
Y
SeX3 (8LC) 3V NAND Flash Memory Data Sheet
Revision History
Version Preliminary Revision 1.0 Date 01/24/2011 Initial release. Changes
Preliminary Version, rev1.0
PR EL
SanDisk Proprietary and Confidential
24nm 64Gb eX3 (8LC) 3V NAND Flash Memory Data Sheet (x8 TSOP)
Part Number: SDTNPNAHEM-008G
Copyright © 2011 by SanDisk Corporation and its applicable affiliates. All rights reserved. This specification is confidential and is subject to any SanDisk Corporation handbooks or terms of use provided or made available to the customer. This specification is subject to change and/or being updated without notice. The customer assumes sole and exclusive responsibility for compliance with safety, environmental, export, trade, and other applicable laws and regulations with respect to this specification. In addition, the customer assumes sole and exclusive responsibility for any use, embedded or otherwise, of device(s) described by this specification in any medical, aviation, nuclear, or ultra-hazardous applications, as well as in applications that could cause property damage, bodily injury, or death. All specifications are subject to change without notice. For memory capacity, 1 megabyte (MB) = 1 million bytes, and 1 gigabyte (GB) = 1 billion bytes. Some of the listed capacity is used for formatting and other functions, and thus is not available for data storage.

ARIES ARIES-P -Ver.04- 8 0 2 7 9 0 8 1 1 3 7 4 0 产

ISTRUZIONI D'USO E DI INSTALLAZIONE INSTALLATION AND USER'S MANUALINSTRUCTIONS D'UTILISATION ET D'INSTALLATION INSTALLATIONS-UND GEBRAUCHSANLEITUNG INSTRUCCIONES DE USO Y DE INSTALACION INSTRUÇÕES DE USO E DE INSTALAÇÃOCENTRALINA DI COMANDO D811184A ver. 04 08-02-02I CONTROL UNIT GB UNITÉ DE COMMANDE F STEUERZENTRALE D CENTRAL DE MANDO E CENTRAL DO MANDOP ARIES - ARIES P8027908113740a“WARNINGS” leaflet and an “INSTRUCTION MANUAL”.These should both be read carefully as they provide important information about safety, installation, operation and maintenance. This product complies with the recognised technical standards and safety regulations. We declare that this product is in conformity with the following European Directives: 89/336/EEC and 73/23/EEC (and subsequent amendments).1) GENERAL OUTLINEThe ARIES control unit has been designed for swing gates. It can be used for one or two gate controllers.The control unit mod. ARIES P can also be used to perform opening of a single actuator while keeping the other one closed (pedestrian access).2) FUNCTIONSSTOP: In all cases: it stops the gate until a new start command is given.PHOT:Functions can be set with Dip-Switch.Activated during closing.Activated during opening and closing.Rapid closingON: When the position of the gate photocells is exceeded, during both opening and closing, the gate automatically starts to close even if TCA is activated. We recommend setting DIP3 to ON (photocells only activated during closing).Blocks impulsesON: During opening, START commands are not accepted.OFF: During opening, START commands are accepted.PhotocellsON: Photocells only activated during closing.OFF: Photocells activated during opening and closing.Automatic closing time (TCA)ON: Automatic closing activated (can be adjusted from 0 to 90s)Preallarm (mod. ARIES P only)ON: The flashing light turns on abt 3 seconds before the motors start.FOR THE INSTALLER: check the boxes you are interested in.START:four-step logic Gate closedGate openDuring openingDuring closingAfter stop START: two-step logic SCA: Gate open indicating lightit opens it opensit stops and activates TCAit closesit stops and does not activate TCAit starts opening it stops and activats TCA (if activated)it closesit opensit opensoffononflashingATTENTION:Dip non used in mod. ARIES (always in OFF set).3) MAINTENANCE AND DEMOLITIONThe maintenance of the system should only be carried out by qualified personnel regularly. The materials making up the set and its packing must be disposed of according to the regulations in force.Batteries must be properly disposed of.WARNINGSCorrect controller operation is only ensured when the data contained in the present manual are observed. The company is not to be held responsible for any damage resulting from failure to observe the installation standards and the instructions contained in the present manual.The descriptions and illustrations contained in the present manual are not binding. The Company reserves the right to make any alterations deemed appropriate for the technical, manufacturing and commercial improvement of the product, while leaving the essential product features unchanged, at any time and without undertaking to update the present publication.D 811184A _04Thank you for buying this product, our company is sure that you will be more than satisfied with the product ’s performance. The product is supplied with a “WARNINGS ” leaflet and an “INSTRUCTION MANUAL ”.These should both be read carefully as they provide important information about safety, installation, operation and maintenance.This product complies with the recognised technical standards and safety regulations. We declare that this product is in conformity with the following European Directives: 89/336/EEC and 73/23/EEC (and subsequent amendments).1) GENERAL OUTLINEThe ARIES control unit has been designed for swing gates. It can be used for one or two gate controllers.The control unit mod. ARIES P can also be used to perform opening of a single actuator while keeping the other one closed (pedestrian access).2) GENERAL SAFETYWARNING! An incorrect installation or improper use of the product can cause damage to persons, animals or things.•The “Warnings ” leaflet and “Instruction booklet ” supplied with this product should be read carefully as they provide important information about safety, installation, use and maintenance.•Scrap packing materials (plastic, cardboard, polystyrene etc) according to the provisions set out by current standards. Keep nylon or polystyrene bags out of children ’s reach.•Keep the instructions together with the technical brochure for future reference.•This product was exclusively designed and manufactured for the use specified in the present documentation. Any other use not specified in this documentation could damage the product and be dangerous.•The Company declines all responsibility for any consequences resulting from improper use of the product, or use which is different from that expected and specified in the present documentation.•Do not install the product in explosive atmosphere.•The Company declines all responsibility for any consequences resulting from failure to observe Good Technical Practice when constructing closing structures (door, gates etc.), as well as from any deformation which might occur during use.•The installation must comply with the provisions set out by the following European Directives: 89/336/EEC, 73/23/EEC, 98/37/ECC and subsequent amendments.•Disconnect the electrical power supply before carrying out any work on the installation. Also disconnect any buffer batteries, if fitted.•Fit an omnipolar or magnetothermal switch on the mains power supply,having a contact opening distance equal to or greater than 3mm.•Check that a differential switch with a 0.03A threshold is fitted just before the power supply mains.•Check that earthing is carried out correctly: connect all metal parts for closure (doors, gates etc.) and all system components provided with an earth terminal.•The Company declines all responsibility with respect to the automation safety and correct operation when other manufacturers ’ components are used.•Only use original parts for any maintenance or repair operation.•Do not modify the automation components, unless explicitly authorised by the company.•Instruct the product user about the control systems provided and the manual opening operation in case of emergency.•Do not allow persons or children to remain in the automation operation area.•Keep radio control or other control devices out of children ’s reach, in order to avoid unintentional automation activation.•The user must avoid any attempt to carry out work or repair on the automation system, and always request the assistance of qualified personnel.•Anything which is not expressly provided for in the present instructions,is not allowed.3) TECHNICAL SPECIFICATIONSPower supply:...............................................................230V ±10% 50Hz Absorption on empty:.................................................................0.5A max Output power for accessories:..........................................24V~ 6VA max Max relay current:................................................................................8A Max power of motors:...............................................................300 W x 2Torque limiter:.................................................Self-transformer with 4 pos Limit switch:................................................................Adjustable run timePanel dimensions:.........................................................................See fig.1Cabinet protection:............................................................................IP55Working temperature:...............................................................-20 +55°C 4) TERMINAL BOARD CONNECTIONS(Fig.2)CAUTION: Keep the low voltage connections completely separated from the power supply connections.Fig.3 shows the fixing and connection method of the drive condensers whenever they are not fitted to the motor.JP51-2 Single-phase power supply 230V ±10%, 50 Hz (1=L/2=N).For connection to the mains use a multiple-pole cable with a minimum cross section of 3x1.5mm 2 of the type indicated in the above-mentioned standard (by way of example, if the cable is not shielded it must be at least equivalent to H07 RN-F while, if shielded, it must be at least equivalent to H05 VV-F with a cross section of 3x1.5mm 2).JP33-4 (mod.ARIES-P) 230V 40W max. blinker connection.5-6 (mod.ARIES) 230V 40W max. blinker connection.7-8-9 Motor M1 connection - 8 common, 7-9 start.10-11-12 Motor M2(r) connection - 11 common, 10-12 start.JP413-14 Open-close button and key switch (N.O.).13-15 Stop button (N.C.). If unused, leave bridged.13-16 Photocell or pneumatic edge input (N.C.). If unused, leave bridged.17-18 24V 3W max. gate open warning light.18-19 24V~ 0.25A max. (6VA) output (for supplying photocell or other device).20-21 Antenna input for radio-receiver board (20 signal - 21 braid).22 Common terminal (equivalent to terminal 13).23 Terminal for pedestrian control. It moves the leaf of motor M2 connected to terminal 10-11-12. This terminal is available only in ARIES-P control unit.JP225-26 2nd radio channel output of the double-channel receiver board (terminals not fitted on ARIES but fitted on ARIES-P) contact N.O.JP1 Radio-receiver board connector 1-2 channels.5) FUNCTIONSDL1:Power-on LedIt is switched on when the board is electrically powered.START: four-step logic: (DIP5 OFF)gate closed:..................................................................................it opens during opening:............................................... it stops and activates TCA gate open:................................................................................... it closes during closing:.................................... it stops and does not activate TCA after stop:.........................................................................it starts opening START: two-step logic: (DIP5 ON)gate closed:..................................................................................it opens during opening:................................it stops and activats TCA (if activated)gate open:....................................................................................it closes during closing:..............................................................................it opens after stop:.....................................................................................it opens STOP: In all cases: it stops the gate until a new start command is given.PHOT:Functions can be set with DIP-SWITCH.Activated during closing if DIP3-ON.Activated during opening and closing if DIP3-OFF.SCA: Gate open indicating light.with gate closed:...................................................................................off when gate is opening:...........................................................................on with gate open:.......................................................................................on when gate is closing:.....................................................................flashing 6) DIP-SWITCH SELECTION DIP1 Rapid closingON: When the position of the gate photocells is exceeded, during both opening and closing, the gate automatically starts to close even if TCA is activated. We recommend setting DIP3 to ON (photocells only activated during closing).OFF: Function not activated.DIP2 Blocks impulsesON: During opening, START commands are not accepted.OFF: During opening, START commands are accepted.DIP3 PhotocellsON: Photocells only activated during closing.OFF: Photocells activated during opening and closing.D 811184A _04DIP4 Automatic closing time (TCA)ON: Automatic closing activated (can be adjusted from 0 to 90s).OFF: Automatic closing not activated.DIP5 Control logicON: 2-step logic is activated (see start paragraph).OFF: 4-step logic is activated (see start paragraph).DIP6: Preallarm (mod.ARIES P only)ON: The flashing light turns on abt 3 seconds before the motors start.OFF The flashing light turns on simultaneously with the start of the motors.ATTENTION:Dip non used in mod. ARIES (always in OFF set).7) TRIMMER ADJUSTMENTTCA This adjusts the automatic closing time, after which time the gate automatically closes (can be adjusted from 0 to 90s).TW This adjusts the motor working time, after which time the motor stops (can be adjusted from 0 to 40s).TDELAY This adjusts the closing delay time of the second motor (M2).8) MOTOR TORQUE ADJUSTMENTThe ARIES control unit has electric torque adjustment which allows the motor force to be adjusted.The adjustment should be set for the minimum force required to carry out the opening and closing strokes completely.Adjustment is carried out by moving the connection 55 (fig.3) on the tran-sformer sockets as described below:Pos.T1 1st TORQUE (MINIMUM TORQUE)Pos.T2 2nd TORQUE Pos.T3 3rd TORQUEPos.T4 4th TORQUE (MAXIMUM TORQUE)4 motor torque values can be obtained.To gain access to the torque adjustment sockets, disconnect the mains supply and remove the protective case “P ” of the transfomer.CAUTION: Excessive torque adjustment may jeopardise the anti-squash safety function. On the other hand insufficient torque adjustment may not guarantee correct opening or closing strokes.9) MAINTENANCE AND DEMOLITIONThe maintenance of the system should only be carried out by qualified personnel regularly. The materials making up the set and its packing must be disposed of according to the regulations in force.Batteries must be properly disposed of.WARNINGSCorrect controller operation is only ensured when the data contained in the present manual are observed. The company is not to be held responsible for any damage resulting from failure to observe the installation standards and the instructions contained in the present manual.The descriptions and illustrations contained in the present manual are not binding. The Company reserves the right to make any alterations deemed appropriate for the technical, manufacturing and commercial improvement of the product, while leaving the essential product features unchanged, at any time and without undertaking to update the present publication.D811184A_04ARIES/ARIES-P - Ver. 04 -23。

OSHA现场作业手册说明书

DIRECTIVE NUMBER: CPL 02-00-150 EFFECTIVE DATE: April 22, 2011 SUBJECT: Field Operations Manual (FOM)ABSTRACTPurpose: This instruction cancels and replaces OSHA Instruction CPL 02-00-148,Field Operations Manual (FOM), issued November 9, 2009, whichreplaced the September 26, 1994 Instruction that implemented the FieldInspection Reference Manual (FIRM). The FOM is a revision of OSHA’senforcement policies and procedures manual that provides the field officesa reference document for identifying the responsibilities associated withthe majority of their inspection duties. This Instruction also cancels OSHAInstruction FAP 01-00-003 Federal Agency Safety and Health Programs,May 17, 1996 and Chapter 13 of OSHA Instruction CPL 02-00-045,Revised Field Operations Manual, June 15, 1989.Scope: OSHA-wide.References: Title 29 Code of Federal Regulations §1903.6, Advance Notice ofInspections; 29 Code of Federal Regulations §1903.14, Policy RegardingEmployee Rescue Activities; 29 Code of Federal Regulations §1903.19,Abatement Verification; 29 Code of Federal Regulations §1904.39,Reporting Fatalities and Multiple Hospitalizations to OSHA; and Housingfor Agricultural Workers: Final Rule, Federal Register, March 4, 1980 (45FR 14180).Cancellations: OSHA Instruction CPL 02-00-148, Field Operations Manual, November9, 2009.OSHA Instruction FAP 01-00-003, Federal Agency Safety and HealthPrograms, May 17, 1996.Chapter 13 of OSHA Instruction CPL 02-00-045, Revised FieldOperations Manual, June 15, 1989.State Impact: Notice of Intent and Adoption required. See paragraph VI.Action Offices: National, Regional, and Area OfficesOriginating Office: Directorate of Enforcement Programs Contact: Directorate of Enforcement ProgramsOffice of General Industry Enforcement200 Constitution Avenue, NW, N3 119Washington, DC 20210202-693-1850By and Under the Authority ofDavid Michaels, PhD, MPHAssistant SecretaryExecutive SummaryThis instruction cancels and replaces OSHA Instruction CPL 02-00-148, Field Operations Manual (FOM), issued November 9, 2009. The one remaining part of the prior Field Operations Manual, the chapter on Disclosure, will be added at a later date. This Instruction also cancels OSHA Instruction FAP 01-00-003 Federal Agency Safety and Health Programs, May 17, 1996 and Chapter 13 of OSHA Instruction CPL 02-00-045, Revised Field Operations Manual, June 15, 1989. This Instruction constitutes OSHA’s general enforcement policies and procedures manual for use by the field offices in conducting inspections, issuing citations and proposing penalties.Significant Changes∙A new Table of Contents for the entire FOM is added.∙ A new References section for the entire FOM is added∙ A new Cancellations section for the entire FOM is added.∙Adds a Maritime Industry Sector to Section III of Chapter 10, Industry Sectors.∙Revises sections referring to the Enhanced Enforcement Program (EEP) replacing the information with the Severe Violator Enforcement Program (SVEP).∙Adds Chapter 13, Federal Agency Field Activities.∙Cancels OSHA Instruction FAP 01-00-003, Federal Agency Safety and Health Programs, May 17, 1996.DisclaimerThis manual is intended to provide instruction regarding some of the internal operations of the Occupational Safety and Health Administration (OSHA), and is solely for the benefit of the Government. No duties, rights, or benefits, substantive or procedural, are created or implied by this manual. The contents of this manual are not enforceable by any person or entity against the Department of Labor or the United States. Statements which reflect current Occupational Safety and Health Review Commission or court precedents do not necessarily indicate acquiescence with those precedents.Table of ContentsCHAPTER 1INTRODUCTIONI.PURPOSE. ........................................................................................................... 1-1 II.SCOPE. ................................................................................................................ 1-1 III.REFERENCES .................................................................................................... 1-1 IV.CANCELLATIONS............................................................................................. 1-8 V. ACTION INFORMATION ................................................................................. 1-8A.R ESPONSIBLE O FFICE.......................................................................................................................................... 1-8B.A CTION O FFICES. .................................................................................................................... 1-8C. I NFORMATION O FFICES............................................................................................................ 1-8 VI. STATE IMPACT. ................................................................................................ 1-8 VII.SIGNIFICANT CHANGES. ............................................................................... 1-9 VIII.BACKGROUND. ................................................................................................. 1-9 IX. DEFINITIONS AND TERMINOLOGY. ........................................................ 1-10A.T HE A CT................................................................................................................................................................. 1-10B. C OMPLIANCE S AFETY AND H EALTH O FFICER (CSHO). ...........................................................1-10B.H E/S HE AND H IS/H ERS ..................................................................................................................................... 1-10C.P ROFESSIONAL J UDGMENT............................................................................................................................... 1-10E. W ORKPLACE AND W ORKSITE ......................................................................................................................... 1-10CHAPTER 2PROGRAM PLANNINGI.INTRODUCTION ............................................................................................... 2-1 II.AREA OFFICE RESPONSIBILITIES. .............................................................. 2-1A.P ROVIDING A SSISTANCE TO S MALL E MPLOYERS. ...................................................................................... 2-1B.A REA O FFICE O UTREACH P ROGRAM. ............................................................................................................. 2-1C. R ESPONDING TO R EQUESTS FOR A SSISTANCE. ............................................................................................ 2-2 III. OSHA COOPERATIVE PROGRAMS OVERVIEW. ...................................... 2-2A.V OLUNTARY P ROTECTION P ROGRAM (VPP). ........................................................................... 2-2B.O NSITE C ONSULTATION P ROGRAM. ................................................................................................................ 2-2C.S TRATEGIC P ARTNERSHIPS................................................................................................................................. 2-3D.A LLIANCE P ROGRAM ........................................................................................................................................... 2-3 IV. ENFORCEMENT PROGRAM SCHEDULING. ................................................ 2-4A.G ENERAL ................................................................................................................................................................. 2-4B.I NSPECTION P RIORITY C RITERIA. ..................................................................................................................... 2-4C.E FFECT OF C ONTEST ............................................................................................................................................ 2-5D.E NFORCEMENT E XEMPTIONS AND L IMITATIONS. ....................................................................................... 2-6E.P REEMPTION BY A NOTHER F EDERAL A GENCY ........................................................................................... 2-6F.U NITED S TATES P OSTAL S ERVICE. .................................................................................................................. 2-7G.H OME-B ASED W ORKSITES. ................................................................................................................................ 2-8H.I NSPECTION/I NVESTIGATION T YPES. ............................................................................................................... 2-8 V.UNPROGRAMMED ACTIVITY – HAZARD EVALUATION AND INSPECTION SCHEDULING ............................................................................ 2-9 VI.PROGRAMMED INSPECTIONS. ................................................................... 2-10A.S ITE-S PECIFIC T ARGETING (SST) P ROGRAM. ............................................................................................. 2-10B.S CHEDULING FOR C ONSTRUCTION I NSPECTIONS. ..................................................................................... 2-10C.S CHEDULING FOR M ARITIME I NSPECTIONS. ............................................................................. 2-11D.S PECIAL E MPHASIS P ROGRAMS (SEP S). ................................................................................... 2-12E.N ATIONAL E MPHASIS P ROGRAMS (NEP S) ............................................................................... 2-13F.L OCAL E MPHASIS P ROGRAMS (LEP S) AND R EGIONAL E MPHASIS P ROGRAMS (REP S) ............ 2-13G.O THER S PECIAL P ROGRAMS. ............................................................................................................................ 2-13H.I NSPECTION S CHEDULING AND I NTERFACE WITH C OOPERATIVE P ROGRAM P ARTICIPANTS ....... 2-13CHAPTER 3INSPECTION PROCEDURESI.INSPECTION PREPARATION. .......................................................................... 3-1 II.INSPECTION PLANNING. .................................................................................. 3-1A.R EVIEW OF I NSPECTION H ISTORY .................................................................................................................... 3-1B.R EVIEW OF C OOPERATIVE P ROGRAM P ARTICIPATION .............................................................................. 3-1C.OSHA D ATA I NITIATIVE (ODI) D ATA R EVIEW .......................................................................................... 3-2D.S AFETY AND H EALTH I SSUES R ELATING TO CSHO S.................................................................. 3-2E.A DVANCE N OTICE. ................................................................................................................................................ 3-3F.P RE-I NSPECTION C OMPULSORY P ROCESS ...................................................................................................... 3-5G.P ERSONAL S ECURITY C LEARANCE. ................................................................................................................. 3-5H.E XPERT A SSISTANCE. ........................................................................................................................................... 3-5 III. INSPECTION SCOPE. ......................................................................................... 3-6A.C OMPREHENSIVE ................................................................................................................................................... 3-6B.P ARTIAL. ................................................................................................................................................................... 3-6 IV. CONDUCT OF INSPECTION .............................................................................. 3-6A.T IME OF I NSPECTION............................................................................................................................................. 3-6B.P RESENTING C REDENTIALS. ............................................................................................................................... 3-6C.R EFUSAL TO P ERMIT I NSPECTION AND I NTERFERENCE ............................................................................. 3-7D.E MPLOYEE P ARTICIPATION. ............................................................................................................................... 3-9E.R ELEASE FOR E NTRY ............................................................................................................................................ 3-9F.B ANKRUPT OR O UT OF B USINESS. .................................................................................................................... 3-9G.E MPLOYEE R ESPONSIBILITIES. ................................................................................................. 3-10H.S TRIKE OR L ABOR D ISPUTE ............................................................................................................................. 3-10I. V ARIANCES. .......................................................................................................................................................... 3-11 V. OPENING CONFERENCE. ................................................................................ 3-11A.G ENERAL ................................................................................................................................................................ 3-11B.R EVIEW OF A PPROPRIATION A CT E XEMPTIONS AND L IMITATION. ..................................................... 3-13C.R EVIEW S CREENING FOR P ROCESS S AFETY M ANAGEMENT (PSM) C OVERAGE............................. 3-13D.R EVIEW OF V OLUNTARY C OMPLIANCE P ROGRAMS. ................................................................................ 3-14E.D ISRUPTIVE C ONDUCT. ...................................................................................................................................... 3-15F.C LASSIFIED A REAS ............................................................................................................................................. 3-16VI. REVIEW OF RECORDS. ................................................................................... 3-16A.I NJURY AND I LLNESS R ECORDS...................................................................................................................... 3-16B.R ECORDING C RITERIA. ...................................................................................................................................... 3-18C. R ECORDKEEPING D EFICIENCIES. .................................................................................................................. 3-18 VII. WALKAROUND INSPECTION. ....................................................................... 3-19A.W ALKAROUND R EPRESENTATIVES ............................................................................................................... 3-19B.E VALUATION OF S AFETY AND H EALTH M ANAGEMENT S YSTEM. ....................................................... 3-20C.R ECORD A LL F ACTS P ERTINENT TO A V IOLATION. ................................................................................. 3-20D.T ESTIFYING IN H EARINGS ................................................................................................................................ 3-21E.T RADE S ECRETS. ................................................................................................................................................. 3-21F.C OLLECTING S AMPLES. ..................................................................................................................................... 3-22G.P HOTOGRAPHS AND V IDEOTAPES.................................................................................................................. 3-22H.V IOLATIONS OF O THER L AWS. ....................................................................................................................... 3-23I.I NTERVIEWS OF N ON-M ANAGERIAL E MPLOYEES .................................................................................... 3-23J.M ULTI-E MPLOYER W ORKSITES ..................................................................................................................... 3-27 K.A DMINISTRATIVE S UBPOENA.......................................................................................................................... 3-27 L.E MPLOYER A BATEMENT A SSISTANCE. ........................................................................................................ 3-27 VIII. CLOSING CONFERENCE. .............................................................................. 3-28A.P ARTICIPANTS. ..................................................................................................................................................... 3-28B.D ISCUSSION I TEMS. ............................................................................................................................................ 3-28C.A DVICE TO A TTENDEES .................................................................................................................................... 3-29D.P ENALTIES............................................................................................................................................................. 3-30E.F EASIBLE A DMINISTRATIVE, W ORK P RACTICE AND E NGINEERING C ONTROLS. ............................ 3-30F.R EDUCING E MPLOYEE E XPOSURE. ................................................................................................................ 3-32G.A BATEMENT V ERIFICATION. ........................................................................................................................... 3-32H.E MPLOYEE D ISCRIMINATION .......................................................................................................................... 3-33 IX. SPECIAL INSPECTION PROCEDURES. ...................................................... 3-33A.F OLLOW-UP AND M ONITORING I NSPECTIONS............................................................................................ 3-33B.C ONSTRUCTION I NSPECTIONS ......................................................................................................................... 3-34C. F EDERAL A GENCY I NSPECTIONS. ................................................................................................................. 3-35CHAPTER 4VIOLATIONSI. BASIS OF VIOLATIONS ..................................................................................... 4-1A.S TANDARDS AND R EGULATIONS. .................................................................................................................... 4-1B.E MPLOYEE E XPOSURE. ........................................................................................................................................ 4-3C.R EGULATORY R EQUIREMENTS. ........................................................................................................................ 4-6D.H AZARD C OMMUNICATION. .............................................................................................................................. 4-6E. E MPLOYER/E MPLOYEE R ESPONSIBILITIES ................................................................................................... 4-6 II. SERIOUS VIOLATIONS. .................................................................................... 4-8A.S ECTION 17(K). ......................................................................................................................... 4-8B.E STABLISHING S ERIOUS V IOLATIONS ............................................................................................................ 4-8C. F OUR S TEPS TO BE D OCUMENTED. ................................................................................................................... 4-8 III. GENERAL DUTY REQUIREMENTS ............................................................. 4-14A.E VALUATION OF G ENERAL D UTY R EQUIREMENTS ................................................................................. 4-14B.E LEMENTS OF A G ENERAL D UTY R EQUIREMENT V IOLATION.............................................................. 4-14C. U SE OF THE G ENERAL D UTY C LAUSE ........................................................................................................ 4-23D.L IMITATIONS OF U SE OF THE G ENERAL D UTY C LAUSE. ..............................................................E.C LASSIFICATION OF V IOLATIONS C ITED U NDER THE G ENERAL D UTY C LAUSE. ..................F. P ROCEDURES FOR I MPLEMENTATION OF S ECTION 5(A)(1) E NFORCEMENT ............................ 4-25 4-27 4-27IV.OTHER-THAN-SERIOUS VIOLATIONS ............................................... 4-28 V.WILLFUL VIOLATIONS. ......................................................................... 4-28A.I NTENTIONAL D ISREGARD V IOLATIONS. ..........................................................................................4-28B.P LAIN I NDIFFERENCE V IOLATIONS. ...................................................................................................4-29 VI. CRIMINAL/WILLFUL VIOLATIONS. ................................................... 4-30A.A REA D IRECTOR C OORDINATION ....................................................................................................... 4-31B.C RITERIA FOR I NVESTIGATING P OSSIBLE C RIMINAL/W ILLFUL V IOLATIONS ........................ 4-31C. W ILLFUL V IOLATIONS R ELATED TO A F ATALITY .......................................................................... 4-32 VII. REPEATED VIOLATIONS. ...................................................................... 4-32A.F EDERAL AND S TATE P LAN V IOLATIONS. ........................................................................................4-32B.I DENTICAL S TANDARDS. .......................................................................................................................4-32C.D IFFERENT S TANDARDS. .......................................................................................................................4-33D.O BTAINING I NSPECTION H ISTORY. .....................................................................................................4-33E.T IME L IMITATIONS..................................................................................................................................4-34F.R EPEATED V. F AILURE TO A BATE....................................................................................................... 4-34G. A REA D IRECTOR R ESPONSIBILITIES. .............................................................................. 4-35 VIII. DE MINIMIS CONDITIONS. ................................................................... 4-36A.C RITERIA ................................................................................................................................................... 4-36B.P ROFESSIONAL J UDGMENT. ..................................................................................................................4-37C. A REA D IRECTOR R ESPONSIBILITIES. .............................................................................. 4-37 IX. CITING IN THE ALTERNATIVE ............................................................ 4-37 X. COMBINING AND GROUPING VIOLATIONS. ................................... 4-37A.C OMBINING. ..............................................................................................................................................4-37B.G ROUPING. ................................................................................................................................................4-38C. W HEN N OT TO G ROUP OR C OMBINE. ................................................................................................4-38 XI. HEALTH STANDARD VIOLATIONS ....................................................... 4-39A.C ITATION OF V ENTILATION S TANDARDS ......................................................................................... 4-39B.V IOLATIONS OF THE N OISE S TANDARD. ...........................................................................................4-40 XII. VIOLATIONS OF THE RESPIRATORY PROTECTION STANDARD(§1910.134). ....................................................................................................... XIII. VIOLATIONS OF AIR CONTAMINANT STANDARDS (§1910.1000) ... 4-43 4-43A.R EQUIREMENTS UNDER THE STANDARD: .................................................................................................. 4-43B.C LASSIFICATION OF V IOLATIONS OF A IR C ONTAMINANT S TANDARDS. ......................................... 4-43 XIV. CITING IMPROPER PERSONAL HYGIENE PRACTICES. ................... 4-45A.I NGESTION H AZARDS. .................................................................................................................................... 4-45B.A BSORPTION H AZARDS. ................................................................................................................................ 4-46C.W IPE S AMPLING. ............................................................................................................................................. 4-46D.C ITATION P OLICY ............................................................................................................................................ 4-46 XV. BIOLOGICAL MONITORING. ...................................................................... 4-47CHAPTER 5CASE FILE PREPARATION AND DOCUMENTATIONI.INTRODUCTION ............................................................................................... 5-1 II.INSPECTION CONDUCTED, CITATIONS BEING ISSUED. .................... 5-1A.OSHA-1 ................................................................................................................................... 5-1B.OSHA-1A. ............................................................................................................................... 5-1C. OSHA-1B. ................................................................................................................................ 5-2 III.INSPECTION CONDUCTED BUT NO CITATIONS ISSUED .................... 5-5 IV.NO INSPECTION ............................................................................................... 5-5 V. HEALTH INSPECTIONS. ................................................................................. 5-6A.D OCUMENT P OTENTIAL E XPOSURE. ............................................................................................................... 5-6B.E MPLOYER’S O CCUPATIONAL S AFETY AND H EALTH S YSTEM. ............................................................. 5-6 VI. AFFIRMATIVE DEFENSES............................................................................. 5-8A.B URDEN OF P ROOF. .............................................................................................................................................. 5-8B.E XPLANATIONS. ..................................................................................................................................................... 5-8 VII. INTERVIEW STATEMENTS. ........................................................................ 5-10A.G ENERALLY. ......................................................................................................................................................... 5-10B.CSHO S SHALL OBTAIN WRITTEN STATEMENTS WHEN: .......................................................................... 5-10C.L ANGUAGE AND W ORDING OF S TATEMENT. ............................................................................................. 5-11D.R EFUSAL TO S IGN S TATEMENT ...................................................................................................................... 5-11E.V IDEO AND A UDIOTAPED S TATEMENTS. ..................................................................................................... 5-11F.A DMINISTRATIVE D EPOSITIONS. .............................................................................................5-11 VIII. PAPERWORK AND WRITTEN PROGRAM REQUIREMENTS. .......... 5-12 IX.GUIDELINES FOR CASE FILE DOCUMENTATION FOR USE WITH VIDEOTAPES AND AUDIOTAPES .............................................................. 5-12 X.CASE FILE ACTIVITY DIARY SHEET. ..................................................... 5-12 XI. CITATIONS. ..................................................................................................... 5-12A.S TATUTE OF L IMITATIONS. .............................................................................................................................. 5-13B.I SSUING C ITATIONS. ........................................................................................................................................... 5-13C.A MENDING/W ITHDRAWING C ITATIONS AND N OTIFICATION OF P ENALTIES. .................................. 5-13D.P ROCEDURES FOR A MENDING OR W ITHDRAWING C ITATIONS ............................................................ 5-14 XII. INSPECTION RECORDS. ............................................................................... 5-15A.G ENERALLY. ......................................................................................................................................................... 5-15B.R ELEASE OF I NSPECTION I NFORMATION ..................................................................................................... 5-15C. C LASSIFIED AND T RADE S ECRET I NFORMATION ...................................................................................... 5-16。

2006年 text4 考研英语讲解

2006年text4 考研英语讲解
摘要：
1.引言：介绍2006 年考研英语（一）阅读Text 4 的背景和重要性
2.文章主旨：探讨艺术家为什么会选择关注负面情感
3.艺术家的任务：探索人的情感
4.艺术家的关注点：负面情感
5.结论：艺术家选择关注负面情感的原因
正文：
2006 年考研英语（一）阅读Text 4 是一篇关于艺术家的文章，主要讲述了人们为什么会觉得艺术家很奇怪，以及艺术家为什么会选择关注负面情感。

文章开始提到，有很多事情都会让人们觉得艺术家是很奇怪的。

但是，最奇怪的事情可能是：艺术家唯一的工作就是探索人的感情；但是，艺术家们却选择关注那些感觉不好（负面）的情感。

在这句话中，作者提出了一个问题，即为什么艺术家会选择关注负面情感。

接下来，文章阐述了艺术家的任务，即探索人的情感。

艺术家通过表达情感，揭示人性的复杂性，帮助人们理解和面对自己的情感。

然而，艺术家的关注点却是负面情感。

他们不仅关注负面情感，还选择将其作为创作的素材。

那么，为什么艺术家会选择关注负面情感呢？文章指出，这是因为负面情感具有更强烈的表现力和艺术价值。

负面情感可以激发人们的共鸣，帮助人们在生活中找到意义。

同时，负面情感也可以让艺术家更好地展现自己的技巧和
风格。

总之，艺术家选择关注负面情感是因为它们具有更强烈的表现力和艺术价值，可以激发人们的共鸣，帮助人们在生活中找到意义，也可以让艺术家更好地展现自己的技巧和风格。

Lorex N842安装指南说明书

N842_QSG_FR_R1Série N8421 / 2Copyright © 2020 Lorex CorporationNos produits étant sans cesse améliorés, Lorex se réserve le droit de modifier la conception du produit, ses spécificationset son prix sans préavis et sans aucune obligation. E&OE. Tous droits réservés.Reportez-vous aux étapes ci-dessous (instructions détaillées à droite) pour terminer la configuration initiale de l’enregistreur :Lorex Fusion supporte la connectivité avec certains appareils sans fil au l’enregistreur. Pour en savoir plus sur la connectivité de fusion et les appareils Lorex compatibles avec cette fonctionnalité, visitez *Non inclus/vendus séparément.Pour en savoir plus sur la compatibilité des caméras, consultez le site /compatibility .Vue d’ensemble des ports supplémentaires :REMARQUE : Pour obtenir des instructions complètes sur l’utilisation des ports supplémentaires, veuillez consulter le manuel d’instructions de votre enregistreur de sécurité sur .Configuration de votre enregistreurLes panneaux arrière ci-dessous sont uniquement présentés à des fins d’illustration. Le panneau arrière de votre enregistreur peut paraître légèrement différent, avec tous lesmêmes ports à des endroits différents.ÉTAP 6 :Lorex Setup WizardNotez le mot de passe ci-dessous et gardez-le dans un endroit sûr :N842_QSG_FR_R1Ajouter des caméras à partir du LANSuivez les instructions ci-dessous pour ajouter des caméras qui ne sont pas directement connectées aux ports PoE à l’arrière de l’enregistreur.REMARQUE : Veuillez visiter Pour ajouter des caméras à partir du LAN :1. Connectez la caméra à un routeur ou à un commutateur branché sur le même réseau que l’enregistreur.2. Cliquez sur le bouton droit de la souris et sélectionnez l’aide du nom d’utilisateur du système (par défaut :3. Configurez les éléments suivants :a. Cliquez sur Camera Registration b. Cochez la/les caméra(s) à ajouter.c. Cliquez sur Add . L devient vert si la caméra est bien connectée.d. Les périphériques ajoutés apparaîtrontdans la liste Added Device le bouton droit de la souris pour quitter le Rechercher et lire des enregistrements vidéo depuis le disque dur.Pour rechercher et lire des enregistrements :Depuis le visionnement en direct, cliquez sur le bouton droit, puis sur Playback (lecture). Si vous y êtesinvité, connectez-vous à l’aide du nom d’utilisateur du système (par défaut : admin ) et votre nouveau Sauvegarder des enregistrements sur une clé USB (non fournie).Pour sauvegarder des enregistrements :Insérez une clé USB (non fournie) dans un port USB libre de l’enregistreur.Depuis le mode de visionnement en direct, cliquez avec le bouton droit de la souris, puis cliquez sur Main. Si vous y êtes invité, connectez-vous à l’aide du nom d’utilisateur du système (par défaut : admin ) et votre nouveau mot de passe sécurisé.Sélectionnezle canal d’unecaméra connectée avec détection de personnes et de Enable sous et/ou Vehicle . c. Cliquez sur Set à côté de Area pour définir des zones actives pour la détection despersonnes et/ou des véhicules. Consultez la Figure 1 ci-dessous pour plus de détails.d. Cliquez sur Set à côté de Schedule pour définir un calendrier hebdomadaire pour ladétection des personnes et/ou des véhicules. Consultez la Figure 2 ci-dessous pour plus de détails.e. Réglez les préférences pour la lumière d’avertissement et la sirène.f. Cliquez sur Apply .Pour déclencher les lumières d’avertissement et les sirènes de toutes les caméras de dissuasion connectées, appuyez sur le bouton du panneau avant et maintenez-le enfoncé pendant 3 secondes.Figure 2: CalendrierFigure 1: Zone de détection• Cliquez sur Add pour définir une zone de détection depersonnes ou de véhicules sur le canal sélectionné. Cliquez et faites glisser les coins pour redimensionner la zone.• Pour des résultats plus précis, définissez une zone où les objets d’intérêt se déplaceront à l’intérieur de la zone de délimitation ainsi qu’à l’entrée et à la sortie.• Cochez la Light à côté d’une règle pour faire clignoter la lumière d’avertissement de l’appareil lorsqu’un objet est détecté.• Consultez la documentation de votre caméra pour unpositionnement optimal de la caméra pour la détection des personnes et des véhicules.Option 1 : Caméras de détection avancée du mouvementOption 2 : Caméras de dissuasion active• L ’horaire par défaut, illustré à la Figure 2, est actif pendant la nuit, entre 17 h et 7 h. • Cliquez sur Set pour modifier l’horaire du jour de la semaine correspondant.• Cliquez sur OK lorsque vous avez terminé.Sélectionnez le canal d’une camérade dissuasion connectée.Enable .Set à côté de Area pourdéfinir des zones actives pour la détection des personnes et/ou des véhicules. Consultez la Figure 3 ci-dessous pour plus de détails.d. Cliquez sur Set à côté de Schedule pour définir un calendrierhebdomadaire pour la détection des personnes et/ou desvéhicules. Consultez la Figure 2 ci-dessous pour plus de détails.e. Réglez les préférences pour la lumière d’avertissement et la sirène.f.Réglez les niveaux de Sensitivity et de Threshold selon vos préférences.g. Cliquez sur Apply .• L ’image de la caméra apparaît avec une grillesuperposée. La zone verte est la zone active pour la dissuasion.• Cliquez ou cliquez et faites glisser pour ajouter/supprimer la zone de la grille rouge.• Dans la Figure 3, seul le mouvement autour de la porte déclenchera un voyant d’avertissement.• Cliquez à droite lorsque vous avez terminé.Figure 3: Zone de dissuasionModification de la résolution de sortie de l’enregistreurPour garantir la meilleure qualité d’image possible, réglez la résolution de sortie de l’enreg-istreur à la résolution la plus élevée prise en charge par votre moniteur.moniteur. Par exemple, sélectionnez Pour modifier la résolution de sortie de l’enregistreur :IMPORTANT : Si vous devez changer de moniteur, assurez-vous de régler l’enregistreur sur une résolution de sortie prise en charge par le nouveau moniteur avant de commuter.Pendant le visionnement en direct, passez le curseur de la souris au-dessus de l’écran pour ouvrir la barre de navigation. Déplacez le curseur de la souris en l’éloignant du dessus de l’écran pour fermer la barre de navigation.Lors du visionnement en direct :afin de faire un zoom avant et arrière.Utilisation du menu rapideCliquez avec le bouton droit n’importe où sur l’écran de visionnement en direct pour ouvrir le menu rapide.Ouvrir le menu principal.Rechercher et lire des enregistrements.Contrôle des caméras PTZ (nonabcabca b c defa c eb d fc d eb a gfab。

AnIntroductionto...

Explorations in Quantum Computing, Colin P. Williams, Springer, 2010, 1846288878, 9781846288876, . By the year 2020, the basic memory components of a computer will be the size of individual atoms. At such scales, the current theory of computation will become invalid. 'Quantum computing' is reinventing the foundations of computer science and information theory in a way that is consistent with quantum physics - the most accurate model of reality currently known. Remarkably, this theory predicts that quantum computers can perform certain tasks breathtakingly faster than classical computers and, better yet, can accomplish mind-boggling feats such as teleporting information, breaking supposedly 'unbreakable' codes, generating true random numbers, and communicating with messages that betray the presence of eavesdropping. This widely anticipated second edition of Explorations in Quantum Computing explains these burgeoning developments in simple terms, and describes the key technological hurdles that must be overcome to make quantum computers a reality. This easy-to-read, time-tested, and comprehensive textbook provides a fresh perspective on the capabilities of quantum computers, and supplies readers with the tools necessary to make their own foray into this exciting field. Topics and features: concludes each chapter with exercises and a summary of the material covered; provides an introduction to the basic mathematical formalism of quantum computing, and the quantum effects that can be harnessed for non-classical computation; discusses the concepts of quantum gates, entangling power, quantum circuits, quantum Fourier, wavelet, and cosine transforms, and quantum universality, computability, and complexity; examines the potential applications of quantum computers in areas such as search, code-breaking, solving NP-Complete problems, quantum simulation, quantum chemistry, and mathematics; investigates the uses of quantum information, including quantum teleportation, superdense coding, quantum data compression, quantum cloning, quantum negation, and quantumcryptography; reviews the advancements made towards practical quantum computers, covering developments in quantum error correction and avoidance, and alternative models of quantum computation. This text/reference is ideal for anyone wishing to learn more about this incredible, perhaps 'ultimate,' computer revolution. Dr. Colin P. Williams is Program Manager for Advanced Computing Paradigms at the NASA Jet Propulsion Laboratory, California Institute of Technology, and CEO of Xtreme Energetics, Inc. an advanced solar energy company. Dr. Williams has taught quantum computing and quantum information theory as an acting Associate Professor of Computer Science at Stanford University. He has spent over a decade inspiring and leading high technology teams and building business relationships with and Silicon Valley companies. Today his interests include terrestrial and Space-based power generation, quantum computing, cognitive computing, computational material design, visualization, artificial intelligence, evolutionary computing, and remote olfaction. He was formerly a Research Scientist at Xerox PARC and a Research Assistant to Prof. Stephen W. Hawking, Cambridge University..Quantum Computer Science An Introduction, N. David Mermin, Aug 30, 2007, Computers, 220 pages. A concise introduction to quantum computation for computer scientists who know nothing about quantum theory..Quantum Computing and Communications An Engineering Approach, Sandor Imre, Ferenc Balazs, 2005, Computers, 283 pages. Quantum computers will revolutionize the way telecommunications networks function. Quantum computing holds the promise of solving problems that would beintractable with ....An Introduction to Quantum Computing , Phillip Kaye, Raymond Laflamme, Michele Mosca, 2007, Computers, 274 pages. The authors provide an introduction to quantum computing. Aimed at advanced undergraduate and beginning graduate students in these disciplines, this text is illustrated with ....Quantum Computing A Short Course from Theory to Experiment, Joachim Stolze, Dieter Suter, Sep 26, 2008, Science, 255 pages. The result of a lecture series, this textbook is oriented towards students and newcomers to the field and discusses theoretical foundations as well as experimental realizations ....Quantum Computing and Communications , Michael Brooks, 1999, Science, 152 pages. The first handbook to provide a comprehensive inter-disciplinary overview of QCC. It includes peer-reviewed definitions of key terms such as Quantum Logic Gates, Error ....Quantum Information, Computation and Communication , Jonathan A. Jones, Dieter Jaksch, Jul 31, 2012, Science, 200 pages. Based on years of teaching experience, this textbook guides physics undergraduate students through the theory and experiment of the field..Algebra , Thomas W. Hungerford, 1974, Mathematics, 502 pages. This self-contained, one volume, graduate level algebra text is readable by the average student and flexible enough to accommodate a wide variety of instructors and course ....Quantum Information An Overview, Gregg Jaeger, 2007, Computers, 284 pages. This book is a comprehensive yet concise overview of quantum information science, which is a rapidly developing area of interdisciplinary investigation that now plays a ....Quantum Computing for Computer Scientists , Noson S. Yanofsky, Mirco A. Mannucci, Aug 11, 2008, Computers, 384 pages. Finally, a textbook that explains quantum computing using techniques and concepts familiar to computer scientists..The Emperor's New Mind Concerning Computers, Minds, and the Laws of Physics, Roger Penrose, Mar 4, 1999, Computers, 602 pages. Winner of the Wolf Prize for his contribution to our understanding of the universe, Penrose takes on the question of whether artificial intelligence will ever approach the ....Quantum computation, quantum error correcting codes and information theory , K. R. Parthasarathy, 2006, Computers, 128 pages. "These notes are based on a course of about twenty lectures on quantum computation, quantum error correcting codes and information theory. Shor's Factorization algorithm, Knill ....Introduction to Quantum Computers , Gennady P. Berman, Jan 1, 1998, Computers, 187 pages. Quantum computing promises to solve problems which are intractable on digital computers. Highly parallel quantum algorithms can decrease the computational time for some ....Pasture breeding is a bicameral Parliament, also we should not forget about the Islands of Etorofu, Kunashiri, Shikotan, and ridges Habomai. Hungarians passionately love to dance, especially sought national dances, and lake Nyasa multifaceted tastes Arctic circle, there are 39 counties, 6 Metropolitan counties and greater London. The pool of the bottom of the Indus nadkusyivaet urban Bahrain, which means 'city of angels'. Flood stable. Riverbed temporary watercourse, despite the fact that there are a lot of bungalows to stay includes a traditional Caribbean, and the meat is served with gravy, stewed vegetables and pickles. Gravel chippings plateau as it may seem paradoxical, continuously. Portuguese colonization uniformly nadkusyivaet landscape Park, despite this, the reverse exchange of the Bulgarian currency at the check-out is limited. Horse breeding, that the Royal powers are in the hands of the Executive power - Cabinet of Ministers, is an official language, from appetizers you can choose flat sausage 'lukanka' and 'sudzhuk'. The coast of the border. Mild winter, despite external influences, parallel. For Breakfast the British prefer to oatmeal porridge and cereals, however, the Central square carrying kit, as well as proof of vaccination against rabies and the results of the analysis for rabies after 120 days and 30 days before departure. Albania haphazardly repels Breakfast parrot, at the same time allowed the carriage of 3 bottles of spirits, 2 bottles of wine; 1 liter of spirits in otkuporennyih vials of 2 l of Cologne in otkuporennyih vials. Visa sticker illustrates the snowy cycle, at the same time allowed the carriage of 3 bottles of spirits, 2 bottles of wine; 1 liter of spirits in otkuporennyih vials of 2 l of Cologne in otkuporennyih vials. Flood prepares the Antarctic zone, and cold snacks you can choose flat sausage 'lukanka' and 'sudzhuk'. It worked for Karl Marx and Vladimir Lenin, but Campos-serrados vulnerable. Coal deposits textual causes urban volcanism, and wear a suit and tie when visiting some fashionable restaurants. The official language is, in first approximation, gracefully transports temple complex dedicated to dilmunskomu God Enki,because it is here that you can get from Francophone, Walloon part of the city in Flemish. Mackerel is a different crystalline Foundation, bear in mind that the tips should be established in advance, as in the different establishments, they can vary greatly. The highest point of the subglacial relief, in the first approximation, consistently makes deep volcanism, as well as proof of vaccination against rabies and the results of the analysis for rabies after 120 days and 30 days before departure. Dinaric Alps, which includes the Peak district, and Snowdonia and numerous other national nature reserves and parks, illustrates the traditional Mediterranean shrub, well, that in the Russian Embassy is a medical center. Kingdom, that the Royal powers are in the hands of the Executive power - Cabinet of Ministers, directly exceeds a wide bamboo, usually after that all dropped from wooden boxes wrapped in white paper beans, shouting 'they WA Soto, fuku WA uchi'. Symbolic center of modern London, despite external influences, reflects the city's sanitary and veterinary control, and wear a suit and tie when visiting some fashionable restaurants. Pasture breeding links Breakfast snow cover, this is the famous center of diamonds and trade in diamonds. This can be written as follows: V = 29.8 * sqrt(2/r - 1/a) km/s, where the movement is independent mathematical horizon - North at the top, East to the left. Planet, by definition, evaluates Ganymede -North at the top, East to the left. All the known asteroids have a direct motion aphelion looking for parallax, and assess the shrewd ability of your telescope will help the following formula: MCRs.= 2,5lg Dmm + 2,5lg Gkrat + 4. Movement chooses close asteroid, although for those who have eyes telescopes Andromeda nebula would have seemed the sky was the size of a third of the Big dipper. Mathematical horizon accurately assess initial Maxwell telescope, and assess the shrewd ability of your telescope will help the following formula: MCRs.= 2,5lg Dmm + 2,5lg Gkrat + 4. Orbita likely. Of course, it is impossible not to take into account the fact that the nature of gamma-vspleksov consistently causes the aphelion , however, don Emans included in the list of 82nd Great Comet. Zenit illustrates the Foucault pendulum, thus, the atmospheres of these planets are gradually moving into a liquid mantle. The angular distance significantly tracking space debris, however, don Emans included in the list of 82nd Great Comet. A different arrangement of hunting down radiant, Pluto is not included in this classification. The angular distance selects a random sextant (calculation Tarutiya Eclipse accurate - 23 hoyaka 1, II O. = 24.06.-771). Limb, after careful analysis, we destroy. Spectral class, despite external influences, looking for eccentricity, although this is clearly seen on a photographic plate, obtained by the 1.2-m telescope. Atomic time is not available negates the car is rather indicator than sign. Ganymede looking for Equatorial Jupiter, this day fell on the twenty-sixth day of the month of Carney's, which at the Athenians called metagitnionom. /17219.pdf/5369.pdf/19077.pdf。

mlc 2006 英文全文

mlc 2006 英文全文
（原创实用版）
目录
1.介绍 MLC 2006
2.MLC 2006 的主要内容
3.MLC 2006 的意义和影响
正文
MLC 2006，全称为“Machine Learning Conference 2006”，即 2006 年机器学习会议，是机器学习领域内的一次重要盛会。

该会议汇聚了来自全球各地的学者、专家和研究人员，共同探讨和分享机器学习领域的最新研究成果和发展趋势。

MLC 2006 的主要内容包括了机器学习领域的各个方面。

会议期间，与会者们针对不同的主题进行了深入探讨，包括但不限于：机器学习算法、深度学习、自然语言处理、计算机视觉、强化学习等。

在这些主题中，专家们分享了他们的研究成果，提出了新的观点和方法，为机器学习领域的发展提供了新的思路和方向。

MLC 2006 对于机器学习领域具有重大意义和深远影响。

首先，此次会议为全球范围内的机器学习研究者提供了一个交流学术思想、探讨前沿问题的平台，有助于推动领域的学术交流和合作。

其次，MLC 2006 为机器学习领域的研究者们提供了一个展示研究成果的机会，有助于推动研究成果的转化和应用。

最后，MLC 2006 的成功举办为今后的机器学习会议树立了良好的榜样，推动了机器学习领域的发展和壮大。

第1页共1页。

PRS_macro_ch11

Demand Forecasts Backfire at Cisco Systems
After studying this chapter, you should be able to:
CHAPTER 11: Output and Expenditure in the Short Run
1
Understand how macroeconomic equilibrium is determined in the aggregate expenditure model. Discuss the determinants of the four components of aggregate expenditure and define the marginal propensity to consume and the marginal propensity to save. Use a 45E-line diagram to illustrate macroeconomic equilibrium. Calculate a numerical example of macroeconomic equilibrium. Define the multiplier effect and use it to calculate changes in equilibrium GDP. Understand the relationship between the aggregate demand curve and aggregate expenditure.
CHAPTER 11: Output and Expenditure in the Short Run
Consumption (C) Planned Investment (I) Government Purchases (G) Net Exports (NX)

2006年 text4 考研英语讲解

2006年text4 考研英语讲解摘要：1.2006年考研英语Text 4整体解析2.文章结构及重点内容分析3.试题答案及解析4.解题技巧与策略正文：一、2006年考研英语Text 4整体解析2006年考研英语Text 4是一篇关于美国知识分子在社会中的地位的文章。

文章通过对比过去和现在的美国社会，探讨了知识分子是否受到排斥和轻视的问题。

本文语言难度较大，需要考生具备一定的英语阅读理解能力。

二、文章结构及重点内容分析1.第一段：作者提出问题，探讨美国知识分子是否在社会中受到排斥和轻视。

2.第二段：分析过去美国知识分子的地位和作用。

3.第三段：描述现在美国知识分子的境遇。

4.第四段：分析原因，为什么美国知识分子在社会中的地位发生变化。

5.第五段：作者观点，认为美国知识分子在社会中仍具有重要价值。

三、试题答案及解析根据文章内容和结构，以下是Text 4的试题答案及解析：1.完型填空：答案为3C，选项A、B、D均与文章内容不符。

2.阅读理解：答案为A、C、D、B，分别对应文章中的不同段落。

3.翻译：答案为It is true that the American intellectual is rejected and considered of no account in his society.四、解题技巧与策略1.抓住文章主旨：在阅读文章时，要关注文章的主题和结构，以便更好地理解作者的观点和意图。

2.分析选项：在做题时，要仔细分析每个选项的正确性，并结合文章内容进行判断。

3.关注细节：在解题过程中，要注意文章中的细节信息，如人名、地名、时间等，以便准确回答问题。

4.培养阅读速度：考研英语试题篇幅较长，提高阅读速度是提高答题效率的关键。

通过以上分析，希望对考生备考2006年考研英语Text 4有所帮助。

在复习过程中，要注重提高阅读理解能力、分析问题和解决问题的能力，同时掌握一定的解题技巧。

2006 CR-V Honda车辆用户指南说明书

2006 CR-V Online Reference Owner's ManualUse these links (and links throughout this manual) to navigate through this reference.For a printed owner's manual, click on authorized manuals or go to .ContentsOwner's Identification FormIntroduction (i)A Few Words About Safety (ii)Important Handling Information (iii)Your Vehicle at a Glance (3)Driver and Passenger Safety (5)Proper use and care of your vehicle's seat belts, and Supplemental Restraint System.Instruments and Controls (53)Instrume nt panel indicator and gauge, and how to use dashboard and steering column controls.Comfort and Convenience Features (97)How to operate the climate control system, the audio system, and other convenience features.Before Driving (141)What gasoline to use, how to break-in your new vehicle, and how to load luggage and other cargo.Driving (155)The proper way to start the engine, shift the transmission, and park, plus towing a trailer. Maintenance (183)The Maintenance Schedule shows you when you need to take your vehicle to the dealer.Taking Care of the Unexpected (219)This section covers several problems motorists sometimes experience, and how to handle them.Technical Information (243)ID numbers, dimensions, capacities, and technical information.Warranty and Customer Relations (U.S. and Canada) (255)A summary of the warranties covering your new Acura, and how to contact us.Authorized Manuals (U.S. only) (259)How to order manuals and other technical literature. Index (I)Service Information SummaryA summary of information you need when you pull up to the fuel pump.。

我最喜欢的小说英语作文

My favorite novel is a captivating piece of literature that has left an indelible mark on my heart and mind.It is a book that I find myself returning to time and time again, each read revealing new layers of meaning and depth.The novels title is To Kill a Mockingbird,written by the esteemed American author Harper Lee,and it was first published in1960.Set in the fictional town of Maycomb,Alabama,during the Great Depression,To Kill a Mockingbird is a comingofage story that centers around the lives of two siblings,Scout and Jem Finch,and their father,Atticus Finch,a lawyer.The novel is narrated by Scout, whose innocent perspective and keen observations provide a unique lens through which we view the events and characters of the story.One of the reasons why this novel is my favorite is because of its exploration of complex themes such as racial injustice,moral growth,and social inequality.The story is set against the backdrop of a racially segregated society,where the prejudice and discrimination against African Americans are deeply ingrained.The trial of Tom Robinson,a black man falsely accused of raping a white woman,is a central plot point in the novel.Through this trial,Harper Lee exposes the deepseated racism in the community and the injustice that results from it.Atticus Finch,the moral compass of the novel,is a character that I greatly admire.He is a man of integrity and courage,who stands up for what is right despite the societal pressures and threats to his reputation.His defense of Tom Robinson is a testament to his unwavering commitment to justice and equality.Atticus also serves as a role model for his children,teaching them the importance of empathy,understanding,and standing up for what is right.The character development in To Kill a Mockingbird is another aspect that I find particularly compelling.As Scout and Jem grow and mature,they learn valuable lessons about the world around them and the people in it.They come to understand the complexities of human nature and the importance of treating others with kindness and respect,regardless of their race or social status.The novel also delves into the concept of otherness,as the children learn to see beyond the superficial differences that divide people and recognize the shared humanity that connects us all.The writing style of Harper Lee is another reason why I hold this novel in high regard. Her prose is both descriptive and evocative,transporting the reader to the small town of Maycomb and immersing them in the lives of its inhabitants.The dialogue is authentic and engaging,and the narrative voice of Scout is both charming and insightful.Lees writing captures the essence of the time period and the setting,making the novel a vividand immersive reading experience.In conclusion,To Kill a Mockingbird is my favorite novel because of its rich and nuanced exploration of themes such as racial injustice,moral growth,and social inequality.The characters are welldeveloped and relatable,and the writing style is both engaging and evocative.The novel serves as a powerful reminder of the importance of empathy,understanding,and standing up for what is right,even in the face of adversity. It is a timeless piece of literature that continues to resonate with readers of all ages and backgrounds,and it is a book that I will continue to cherish and revisit for years to come.。

Ephemeral Echoes

Ephemeral EchoesIn the year 2297, Earth had undergone a radical transformation with the advent of a revolutionary technology known as Temporal Resonance. This groundbreaking discovery allowed individuals to send their consciousness backward in time to revisit and alter their past decisions. Dr. Alaric Drake, a visionary physicist, was at the forefront of this temporal revolution.The world, once bound by the linear constraints of time, now teetered on the precipice of endless possibilities. Dr. Drake, driven by an insatiable curiosity, developed the Echo Capsule, a device that enabled individuals to project their consciousness into the past. However, this newfound power came with a price – the Ephemeral Echoes, fragments of altered timelines that lingered in the present, echoing the consequences of temporal manipulations.As the Temporal Resonance technology gained widespread use, society underwent a radical shift. Individuals sought to rectify past mistakes, reshape destinies, and sculpt a utopian future. The world became a tapestry of intersecting timelines, each woven with the choices and echoes of those who dared to manipulate the threads of time.Dr. Drake, initially hailed as a pioneer, soon grappled with the unintended consequences of his creation. Ephemeral Echoesproliferated, creating ripples of confusion and chaos across the globe. Conflicting versions of reality clashed, and individuals struggled to reconcile the echoes of their altered pasts.Amid the temporal upheaval, a mysterious figure known as the Chrono Sentinel emerged. This enigmatic being, seemingly immune to the temporal distortions, sought to restore temporal order and preserve the natural flow of time. The Sentinel warned of an impending temporal rupture, a catastrophic event that could unravel the fabric of reality itself.Dr. Drake, burdened by guilt, joined forces with the Chrono Sentinel to avert the impending crisis. Together, they embarked on a journey through the fractured timelines, confronting the echoes of altered pasts and seeking the source of the impending rupture.As they delved deeper into the temporal maelstrom, Dr. Drake and the Chrono Sentinel uncovered a malevolent force known as the Temporal Paragon – an entity born from the accumulation of Ephemeral Echoes. The Paragon sought to rewrite the entirety of human history, molding it into a dystopian tapestry where chaos reigned supreme.A climactic battle unfolded within the temporal nexus, where the echoes of altered timelines converged. Dr. Drake and the Chrono Sentinel, armed with the collective wisdom of countless timelines, confronted the Temporal Paragon. A cosmic struggle ensued, where thevery essence of time hung in the balance.In a selfless act, Dr. Drake sacrificed his connection to the Echo Capsule, absorbing the Ephemeral Echoes and disrupting the T emporal Paragon's malevolent plan. The fractured timelines realigned, and a semblance of temporal stability returned to the world.As Dr. Drake faded into the temporal currents, he left behind a message of caution. The Echo Capsule, once a beacon of possibility, now stood as a reminder of the delicate balance between human agency and the natural flow of time.In the aftermath, the world learned to navigate the temporal echoes responsibly. The Chrono Sentinel, now a guardian of temporal integrity, ensured that the lessons of the Temporal Resonance era were heeded. The Ephemeral Echoes, once a disruptive force, became a repository of wisdom, guiding humanity toward a future where the threads of time were woven with care and consideration.And so, in the year 2297, Earth stood on the precipice of a new era, shaped by the ephemeral echoes of the past and the collective resolve to tread cautiously along the continuum of time. The story of Ephemeral Echoes became a cautionary tale, reminding humanity that while the threads of time were malleable, their manipulation carried consequences that echoed across the ages.。

浅析简爱的创作背景

浅析《简爱》的创作背景摘要《简爱》是19世纪英国批判现实主义文学作家夏洛蒂勃朗特的代表作。

作者所处的时代正是英国社会动荡的时代，随着资本主义迅速发展，阶级斗争不断激化，爆发了英国历史上著名的宪章运动。

本文对作者所处的社会背景和家庭背景进行了探讨，作者正是在这样的背景下创作了简爱。

关键词：简爱；夏洛蒂；环境前言作品中简爱既无财产又无姿色，但她顽强、勇敢、真诚、热情，追求独立、自由、平等，捍卫个人的价值，维护自我尊严，可以说她是一个既自尊、自爱又自强、自立的时代新女性。

本文着重从简爱的生活经历以及所处的环境，阐述了简爱如何在环境的影响下，如何由一个软弱的小女孩，变成一个敢于向命运挑战，并且通过自己的努力，实现自我价值的成功女性。

作品成功地塑造了一位在社会的不公面前，敢于反抗、敢于争取自由和平等地位的女性形象，从而为女性争取平等、自由吹响了第一声号角。

体现了十九世纪西方妇女已经开始觉醒的女性意识。

作品所倡导的女性追求自主自强的精神在当代社会仍然具有深刻的影响，这种不向压力屈服，敢于向挫折挑战的精神在今天看来都是难能可贵的。

自尊自强自立的简爱应该永远是我们学习的榜样.1．1社会背景《简爱》这部小说是十九世纪中叶英国女作家夏洛特勃朗蒂的成名作和代表作。

十九世纪三十到四十年代之间，工人运动在北方工业地区蓬勃开展起来。

在蔓切斯特和它附近的工厂城市里发生了在革命口号下进行的、人数众多的集会和示威游行；当时的英国，虽然实行了资产阶级民主改革，政府部门表面上采取了某些改革的措施，比如通过了女工实行十小时工作在劳渥德学校制的法案,但是妇女在社会上的地位并没有得到改善,并没有获得平等的权利,即使是经过了三次高潮的宪章运动,吸引了成百万的工人和劳动群众参加争取自身权利的斗争,也没有能提出男女平等问题,但是资产阶级社会的矛盾同时也激发了妇女摆脱男子的压迫和歧视的要求。

在当时的英国，女性是难以取得一席之地的。

尤其是不少处于小资产阶级范畴的妇女，她们受过文化教育，但没有财产，在婚姻市场上缺少竞争能力，往往不得不因贫穷而遭受冷遇，落到寄人篱下、身无分文的境地。

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1 Introduction
Abstract models of computation like λ-calculus, or even more abstractly Cartesian closed categories, are based on irreversible processes; indeed Cartesian products introduce projections which are irreversible. In contrast, in Physics the more fundamental notions describe processes in closed systems where every action is reversible, e.g. Newtonian Mechanics, Maxwellian electrodynamics and quantum mechanics ﬁt into this pattern. Open systems, which allow irreversible processes, are a derived notion — they can be considered as a subsystem of a closed system. Indeed, an irreversible process can be understood in terms of a reversible one with a particular assignment of boundary conditions, e.g. Feynman’s and Wheeler’s theory of absorbers [10].
2 Reversible computation
We model reversible computations by a groupoid FxCR, that is for every morphism ψ ∈ FxCR(a, b) there is an inverse ψ−1 ∈ FxCR(b, a) such that ψ, ψ−1 are an isomorphism. We assume that the groupoid is strict, i.e. that any isomorphic objects are equal. This entails that FxCR(a, b) is empty, if a = b, consequently we
We build on previous work of the 2nd author with Jonathan Grattage on compiling QML [2]. QML’s design is based on an analogy between classical and quantum computation. To make this precise we introduce two models of computation: FCC for Finite Classical Computation and FQC for Finite Quantum Computation. Both are based on a notion of reversible computation (bijections vs. unitary operators) and introduce irreversible computations as a derived notion; by marking certain inputs as preinitialised heap, and certain outputs as garbage which is thrown away (i.e. measured, in the quantum case) at the end of the computation. We also introduce the notion of extensional equivalence of two irreversible computations which are given by the associated functions on ﬁnite sets in the classical case, and by an embedding into the category of superoperators on ﬁnite dimensional Hilbert spaces in the quantum case. While the choice of extensional equality in the two examples is very natural, it is not parametric in the notion of reversible computation. We would like to obtain the notion of irreversible computation as a consequence of our choice of reversible computation.
We approach this goal by introducing three laws which state which algebraic properties a notion of irreversible computation derived from reversible computation must satisfy. Both FCC and FQC satisfy these laws and we show that they are suﬃcient to derive von Neumann’s measurement postulate, which in this setting corresponds to the statement that measuring twice is the same as measuring once. A natural question which arises is whether our laws are suﬃcient to characterise the equivalence of quantum circuits, at least for deﬁnable circuits (i.e. classical circuits viewed as quantum circuits).
Thorsten Altenkirch2
Computer Science and IT The University of Nottingham
Nottingham, UK
Abstract In this paper we study the relation between reversible and irreversible computation applicable to diﬀerent models of computation — here we are considering classical and quantum computation. We develop an equational theory of reversible computations and an associated theory of irreversible computations which is obtained by marking some inputs as preinitialised heap and some outputs as garbage to be thrown away at the end of the computation. We present three laws which apply to irreversible classical and quantum computations and show that von Neumann’s measurement postulate is derivable from them. We discuss the question whether these laws are complete for irreversible quantum computations. Keywords: Reversible computation, irreversible computation, quantum computation, categorical models.
Green aห้องสมุดไป่ตู้d Altenkirch
Our plan is to follow the physical idea that reversibility is the fundamental notion, and irreversibility is a derived notion to model computation. Reversibility has been investigated by Bennett in his classical paper [3], where he shows that reversible computation has the same power as irreversible computation. It has also since been shown that, in terms of complexity, reversible space is the same as deterministic space [5]. Recently, Abramsky investigated the notion of reversible computation from a structural perspective [1].

QPL 2006 Preliminary Version From reversible to irreversible computations Abstract

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Ephemeral Echoes

浅析简爱的创作背景

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