Alii An information integration environment based on the active logic framework
Firm crash risk, information environment, and speed of leverage adjustment
Firm crash risk,information environment,and speed of leverage adjustment ☆Zhe An a,b ,Donghui Li c,⁎,Jin Yu b,⁎⁎a Faculty of Economics and Business,Monash University,Australiab UNSW School of Business,University of New South Wales,Australia cSun Yat-sen Business School (SYSBS),Sun Yat-sen University,Chinaa r t i c l e i n f o ab s t r ac tArticle history:Received 14May 2013Received in revised form 21January 2015Accepted 22January 2015Available online 30January 2015This paper examines the effect of a firm's crash-risk exposure on its speed of leverage adjustment (SOA),and how this effect is in fluenced by the information environment of the country in which the firm is located.We employ a panel of 19,247firms across 41countries from 1989to 2013,and we find that firms with a higher crash-risk exposure tend to adjust their financial leverages more slowly toward their targets.This evidence supports the dynamic trade-off theory that firms with larger transaction costs adjust their capital structures less often.Equally important,we document that the negative link between crash-risk exposure and SOA is less pronounced in countries with a more transparent information environment.©2015Elsevier B.V.All rights reserved.JEL classi fication:G32G15Keywords:Capital structure dynamics Information asymmetry Crash riskInformation environment1.IntroductionExisting capital structure theories demonstrate that information asymmetry is an important determinant of optimal leverage.For example,Myers (1984)and Myers and Majluf (1984)show that firms with high information asymmetry face large external financing costs.The signaling theory of capital structure suggests that the stock market positively (negatively)reacts to an announcement of debt (equity)issuance (Ross,1977;Noe,1988).Moreover,the dynamic trade-off theory allows firms to take into account a trade-off between a suboptimal financial structure and leverage adjustment costs (Fischer et al.,1989;Goldstein et al.,2001;Strebulaev,2007).Therefore,it predicts that firms with higher transaction costs tend to adjust their leverage ratios more slowly toward their targets.One anecdotal example is the stock-price crash of Olympus in 2011caused by its accounting scandal.The Japanese company paid in flated advisory fees to takeover advisers in order to hide investment losses in the 1990s.After its former president and CEO,Michael C.Woodford,questioned the fees of the Gyrus acquisition,Olympus'stock fell 70%within three weeks (from mid-October to Novem-ber 8,2011),re flecting investors'concerns about the company's actual prospects.In particular,Olympus'shareholders were worriedJournal of Corporate Finance 31(2015)132–151☆We thank Jerry Cao,Fauzias Mat Nor,Erkan Yonder and conference participants at Asian Finance Association Annual Meetings 2012,Australasian Finance and Banking Annual Conference 2013,Financial Management Association European Annual Meetings 2014,and seminar participants at Beihang University and the University of New South Wales.All errors remain ours.⁎Corresponding author.Tel.:+862084113634;fax:+862084036924.⁎⁎Corresponding author.Tel.:+61293857886;fax:+61293856347.E-mail addresses:donghuiac@ (D.Li),jin.yu@.au (J.Yu)./10.1016/j.jcorp fin.2015.01.0150929-1199/©2015Elsevier B.V.All rightsreserved.Contents lists available at ScienceDirectJournal of Corporate Financej o ur n a l h o m e p a g e :w ww.e l s e v i e r.c om /l o c a t e /j c o r p f i nabout the company being delisted from the Tokyo Stock Exchange,which could restrict access to external equity financing.In addition,the company's credit rating was downgraded,suggesting that its creditworthiness had deteriorated considerably.In this case,reac-tions from capital-market participants were in accord with the prediction that external financing costs increase crash risk (The Wall Street Journal,December 6,2011).In this paper,we investigate how a firm's crash-risk exposure affects its leverage adjustment decision.We argue that firms exposed to a high crash risk are presumably those with extreme information asymmetry between inside managers and outside investors,which is consistent with the evidence of a signi ficant positive relationship between crash risk and extreme information asymmetry in the existing literature (Jin and Myers,2006;Hutton et al.,2009;Kim et al.,2011a ).Thus,we hypothesize that a firm's crash-risk exposure tends to decrease its speed of leverage adjustment (SOA).More importantly,we expect that the negative crash-risk effect on leverage adjustment is attenuated by a transparent information environment because the impact of the macro information environment on different aspects of financial markets,including institu-tional shareholding (Li et al.,2006)foreign investor shareholding (Haw et al.,2004;Gelos and Wei,2005;Leuz et al.,2009),and le-verage adjustment (Oztekin and Flannery,2012),has been well documented.To test our hypotheses,we employ an international sample of 41countries from 1989to ing international data has two advantages.First,our sample includes a large number of crash events.Second,multi-country data allows us to examine the effect of information environments on the relationship between crash risk and capital structure adjustment.We have three main empirical findings.First,we show that crash-risk exposure is signi ficantly and negatively correlated with a firm's speed of capital-structure adjustment toward their bined with the notion that a firm's crash-risk exposure re flects the opaqueness of its accounting information (Hutton et al.,2009;Kim et al.,2011a ).This finding is consistent with capital structure theories based the information asymmetry,which posit that opaque firms face the high transaction costs of issuing external funds (Myers,1984;Myers and Majluf,1984).Furthermore,the documented slow SOA con firms that firms with larger transaction costs tend to adjust their capital structures less frequently (Fischer et al.,1989;Goldstein et al.,2001;Strebulaev,2007).Second,we find that a transparent information environment signi ficantly attenuates the negative relationship between crash-risk exposure and SOA.This result is consistent with the view that the information environment encourages transparent stock prices and reduces exter-nal financing costs (Porta et al.,1998;Bushman et al.,2004).Third,we find that the effect of crash-risk exposure on SOA is negative among over-leveraged firms and mixed among under-leveraged firms.One explanation for the asymmetric effect is that under-leveraged firms with high crash-risk exposure may strategically use debt issuance (as a good signal)to hide bad news.This paper fits into the empirical literature on dynamic capital structure adjustment.The literature starts from assuming a constant SOA across all firms (Fama and French,2002;Flannery and Rangan,2006).Recent studies have advanced the understanding of cross-section variational in SOA.Our paper is mostly related to Faulkender et al.(2012)and Oztekin and Flannery (2012),which employ dynamic partial adjustment models of capital structure to analyze the determinants of SOA.Adding to this strand of research,we introduce crash-risk exposure as an important factor that explains the heterogeneity in SOA.This is because the existing crash-risk literature suggests a positive relationship between crash risk and extreme information asymmetry (Hutton et al.,2009;Kim et al.,2011a ).Speci fically,we use crash risk as a proxy for extreme information asymmetry,and examine its effect on SOA.Furthermore,this paper sheds insight on the impact of corporate governance on capital structure.For example,Antoniou et al.(2008)find that macro-level corporate governance and investor protection are important determinants of leverage ratios.Fan et al.(2012)show that firms in countries with a poor institutional environment are more likely to have high leverage,while Oztekin and Flannery (2012)argue that a better institutional environment lowers the transaction costs of external financing and hence in-creases SOA.In this paper,we focus on the speci fic information environment rather than the legal regime and investor protection.We find that a transparent information environment signi ficantly mitigates the (adverse)effect of crash-risk exposure on SOA.This paper is related to the literature on crash risk.Prior studies (Jin and Myers,2006;Hutton et al.,2009;Kim et al.,2011a ;Kim et al.,2011b ;An and Zhang,2013;Kim et al.,2014;Kim and Zhang,2014;Kim and Zhang,forthcoming )focus on the determinants of crash risk but do not analyze the consequences of crash-risk exposure on corporate policies.We show that crash-risk exposure can in fluence a firm's ability to raise capital and adjust capital structure.This paper also contributes to the study of the impact of macro information environments on financial markets.For example,Gelos and Wei (2005)provide evidence that international funds hold fewer assets in markets with a less transparent (or more opaque)fi-nancial information environment.Li et al.(2006)find that the variations of financial institutional large shareholdings are determined by country level corporate information disclosure requirements.They argue that the strengthened monitoring ability of a strong macro corporate governance environment encourages financial institutions to hold concentrated equity positions.Leuz et al.(2009)show that country-level poor information disclosure rules and weak investor protection deter foreign investment,especially for firms with more earnings management.This paper shows that the macro information environment additionally in fluences lever-age adjustment by firms across the world.The remainder of the paper is organized as follows.Section 2reviews the related literature and develops our hypotheses.Section 3describes our empirical methodology.Section 4discusses data and sample.Section 5presents the empirical results and robustness tests.Section 6concludes the paper.2.Hypothesis developmentOur hypotheses rest on three strands of research.First,there is a rapidly growing body of research on the signi ficant positive re-lationship between crash risk and extreme information asymmetry (Jin and Myers,2006;Hutton et al.,2009;Kim et al.,2011a ;Kim et al.,2011b ;An and Zhang,2013;Kim et al.,2014;Kim and Zhang,2014;Kim and Zhang,forthcoming ).One explanation is133Z.An et al./Journal of Corporate Finance 31(2015)132–151134Z.An et al./Journal of Corporate Finance31(2015)132–151thatfirm managers tend to keep bad news from capital markets by manipulating accounting information.However,negative informa-tion can no longer be hidden once the accumulated bad news reaches a certain threshold.In such cases,adverse information is sud-denly released tofinancial markets,resulting in a share-price collapse.Therefore,firms exposed to a high crash risk are presumably those with extreme information asymmetry between inside managers and outside investors.Second,Myers(1984)and Myers and Majluf(1984)show thatfirms with a high degree of information asymmetry may incur large transaction costs and,hence,become reluctant to issue risky securities(risky debt and outside equity).Third,the dynamic trade-off theory of capital structure predicts thatfirms take into account a trade-off between transaction costs and a suboptimal leverage ratio when they adjust their leverages toward their targets(Fischer et al.,1989;Goldstein et al.,2001; Strebulaev,2007).When the benefits of an immediate adjustment are outweighed by transaction costs,it becomes optimal for a firm to wait until the accumulated adjustment benefits are large enough to cover recapitalization costs.Several empirical studies pro-vide evidence to support this theory(Fama and French,2002;Leary and Roberts,2005;Flannery and Rangan,2006;Warr et al.,2012; Oztekin and Flannery,2012).Taken all together,we hypothesize thatfirms exposed to a higher crash risk tend to have lower SOA.This forms ourfirst hypothesis.H1.Firms with higher crash-risk exposure are expected to adjust their corporate leverage more slowly.Nevertheless,in countries with a more transparent information environment,firm-level information tends to be released to the market in a more accurate and timely manner.Consistent with this view,Porta et al.(1998)show thatfinancial markets are more ef-ficient and robust in countries with a more transparent information environment.Giannetti(2003)finds that better institutional set-tings could promote debtfinancing.Oztekin and Flannery(2012)find that the transaction costs of externalfinancing are lower and the SOA is higher in countries with a better institutional environment.Hence,we posit that a transparent macro-level information en-vironment may mitigate the negative association between crash-risk exposure and SOA.H2.The negative relationship between crash-risk exposure and SOA is less pronounced amongfirms in countries with a more trans-parent information environment.Furthermore,the signaling theory of capital structure demonstrates that the stock market may react positively to announcements of debt issuances and negatively to announcements of equity issuances.1This implies that the effect of information asymmetry on SOA may depend upon whetherfirms are over-or under-leveraged relative to their target leverage ratios.When adjusting capital struc-ture,over-leveragedfirms usually need to substitute equity for debt,and market participants interpret such an adjustment as a bad signal.To hide bad information,over-leveragedfirms with high crash-risk exposure will be more reluctant to adjust capital structure. Conversely,under-leveragedfirms usually need to substitute debt for equity when making leverage adjustments.Under-leveraged firms that are exposed to a high crash risk may be willing to use debt issuances as a good signal and keep bad news from being released to outside investors.Thus,their leverage adjustments may be smoother.In sum,the existing capital structure theories imply that there is an unambiguous negative link between crash-risk exposure and SOA for over-leveragedfirms.However,theoretical predictions of the relationship between crash-risk exposure and SOA for under-leveragedfirms are mixed.Finally,following Hypothesis2,we conjecture that a transparent information environment reduces the transaction costs of both equity and debt issuances.Consequently,a transparent information environment tends to attenuate the negative relationship between SOA and crash-risk exposure for both over-and under-leveragedfirms.We summarize these consid-erations in the following two hypotheses.H3.Among over-leveragedfirms,those with higher crash-risk exposure are expected to adjust their corporate leverage more slowly, and,this impact is mitigated by a transparent information environment.H4.Among under-leveragedfirms,a transparent information environment enablesfirms with high crash-risk exposure to adjust their capital structures.3.Empirical designIn the literature,both one-step(Flannery and Rangan,2006)and two-step approaches(Hovakimian et al.,2001;Fama and French, 2002;Hovakimian and Li,2011)are used to estimate partial adjustment models.In this paper,which aims to analyze the effect of crash-risk exposure on SOA,as well as the influence of the information environment on this effect,we use the two-step regression framework because it isflexible and allows us to control for otherfirm and country characteristics.In thefirst step,we regress observed leverage on a set of leverage determinants and use thefitted value as a proxy for the unob-servable target leverage.At this stage,we also run a crash-risk predictive regression and extract itsfitted value as a proxy for the un-observable expected crash risk(crash-risk exposure).In the second step,we use both the target leverage and the crash-risk exposure obtained in thefirst step to estimate a partial adjustment model.We focus on the effect of crash-risk exposure on SOA and how this effect interacts with the information environment.The two-step approach is more appropriate in our empirical framework because it can serve to jointly test and distinguish the effects of crash-risk exposure and information environment on SOA.1See Noe(1988)and Ross(1977)for theoretical justification and Masulis(1980)and Masulis(1983)for empirical evidence.Table 1The sample and stock price crash distribution:Panel A provides a description of the sample.Number of years,number of firms,and number of firm-year observations of each country are reported in columns 1–3,respectively.Panel B reports the annual sampling distribution of stock price crash risk from 1989to 2013.Number of firms,number of crashed firms,and percentage of crashed firms of each year are reported in columns 1–3,respectively.The firm is recored as a crashed firm if CRASH equals to one in given firm year (i.e.,the firm experiences one or more than one crash weeks during the year),and zero otherwise.Panel A:The sample MarketN.O.of years N.O.of firms N.O.of firm-year observations [1][2][3]Austria 1433173Belgium 1470501Brazil 1471263Canada 2510383917China 1486527Chile 1738197Denmark 2490676Ireland 1840252Finland 1484624France 145033607Germany 144753338Greece 14133842Hong Kong 248004543Indonesia 172001118India 1715865636Israel 16144504Italy 141871200Japan22203422,440South Korea 2311696748Sri Lanka 654128Malaysia 256034204Mexico1954285Netherlands 16121916Norway24120686New Zealand 2241269Pakistan 1664366Poland 9124477Portugal 1426177Philippines 1771431Russian1165221South Africa 221711169Singapore 254232475Spain 1493644Sweden 252001503Switzerland 211681483Thailand 192732047Turkey 171931250Taiwan175924604United Kingdom 25183912,179United States 25431723,778Total19,247120,764Panel B:Stock price crash distribution YearN.O.of firms N.O.of crashed firms %of crashed firms [1][2][3]198********.85%199074312316.55%199180610412.90%1992106514913.99%1993145820313.92%1994174720911.96%1995196627413.94%1996221826712.04%1997257642216.38%1998261030511.69%199928052799.95%2000367743811.91%2001381050513.25%2002422062214.74%2003480649610.32%2004593375012.64%2005666286312.95%(continued on next page)135Z.An et al./Journal of Corporate Finance 31(2015)132–1513.1.Target leverageEmpirical capital structure research suggests that the target leverage ratio is a function of time-varying firm and industry charac-teristics (Titman and Wessels,1988;Rajan and Zingales,1995;Fama and French,2002;Flannery and Rangan,2006;Lemmon et al.,2008;Frank and Goyal,2009).We regress the observed leverage ratio (L )on a set of leverage factors,estimating the target for both book leverage ratio (BL )and market leverage ratio (ML ):L j ;i ;t ¼αj þγj X j ;i ;t −1þf j ;i þy j ;t þe j ;i ;t ;L ∈BL ;ML f gð1Þwhere country is indexed by j ,firm by i ,and time by t .X j,i,t −1is a vector of firm and industry variables,including firm size (Size a ),tangibility (Tang ),market-to-book ratio (MTB a ),pro fitability (Prof ),depreciation (Dep ),research and development expenses (R&D ),R&D dummy (R&D _dum ),and industry median leverage ratio (IndMed ).2De finitions of the variable are provided in Appendix A .In addition,we control for year fixed effects y j,t and firm fixed effects f j,i in Eq.(1)to capture the unobserved heterogeneity across time and firm.We estimate Eq.(1)by country to allow heterogeneous coef ficient estimators across the 41countries in our sample.Finally,we extract the fitted value of Eq.(1)as a proxy for the target leverage ratio (TL ):TL j ;i ;t ¼^αj þ^γj X j ;i ;t −1þ^f j ;i þ^y j ;t :ð2Þ3.2.Crash-risk measuresIn this paper,we consider three commonly used crash-risk measures in the literature,CR ∈{CRASH ,NCSKEW ,DUVOL },whereCRASH is a crash-event dummy and NCSKEW and DUVOL are measures of stock-return asymmetry.To construct these three measures,we first run an expanded market model (Jin and Myers,2006):r i ;t ¼αi þβ1;i r m ;j ;t þβ2;i r U :S :;t þEX j ;th iþβ3;i r m ;j ;t −1þβ4;i r U :S :;t −1þEX j ;t −1h iþβ5;i r m ;j ;t −2þβ6;i r U :S :;t −2þEX j ;t −2h iþβ7;i r m ;j ;t þ1þβ8;i r U :S :;t þ1þEX j ;t þ1h iþβ9;i r m ;j ;t þ2þβ10;i r U :S :;t þ2þEX j ;t þ2h iþe i ;t ;ð3Þwhere r i,t is the stock return for firm i in week t ,r m,j,t is the local market return for country j in week t ,r U.S.,t is the U.S.market return in week t to proxy global market return,and EX j,t is the change in exchange rate for the currency of country j against the U.S.dollar in week t .Two lead and two lag terms are included to correct the nonsynchronous trading for both the local and U.S.market returns (Dimson,1979).We then calculate firm-speci fic weekly returns W i,t as the natural logarithm of one plus the residual from the expand-ed market model (Eq.(3)),that is,W i,t =log(1+e i,t ).Next,following Hutton et al.(2009)a firm week is de fined as a crash week if the computed firm-speci fic weekly return,W i,t ,is 3.09standard deviations below the mean return for firm i in a given year.3We set the dummy variable CRASH to one if firm i experiences at least one crash week during year t ,and zero otherwise.The same procedure is applied to firms in all countries.2In a standard leverage regression model,firm size and market-to-book ratio are measured based on total assets,but it becomes clear later that they are measured based on equity in the existing crash-risk predictive models.To avoid confusion,we add the superscript a to the variables based on total assets and the superscript e to those based on equity.3Note that 3.09is roughly the 0.1percentile of a standard normal distribution.In a non-normal distribution of weekly returns,a crash week is less likely to be iden-ti fied,whereas in a normal distribution,it is always identi fied (Hutton et al.,2009).Table 1(continued)Panel B:Stock price crash distribution YearN.O.of firms N.O.of crashed firms %of crashed firms [1][2][3]20067676106613.89%20078409108512.90%20088169134916.51%200984077989.49%2010902298810.95%201110,009134613.45%201210,775131112.17%201310,509122411.65%Mean 483161112.96%136Z.An et al./Journal of Corporate Finance 31(2015)132–151The second crash-risk measure (NCSKEW )is the negative skewness of the firm-speci fic weekly return over the year.For each firm in a given year,NCSKEW is calculated by taking the negative of the third moment of firm-speci fic weekly return,and dividing it by the standard deviation of firm-speci fic weekly return raised to the third power (Kim et al.,2011a ;Chen et al.,2001).Speci fically,NCSKEW is computed as:NCSKEW i ;t¼−n n −1ðÞ3=2X W 3i ;t h i =n −1ðÞn −2ðÞX W 2i ;t3=2ð4Þwhere W i,t is the firm-speci fic weekly return derived above,and n is the number of weekly observations of the year.The third crash-risk measure (DUVOL )is calculated as the natural logarithm of the ratio of the standard deviations of down-week and up-week firm-speci fic weekly returns (Chen et al.,2001).A firm-week is de fined as a down (up)-week if the firm-speci fic weekly return is below (above)the yearly mean.Speci fically,DUVOL is computed as:DUVOL i ;t ¼log n u −1ðÞX W 2i d ;t =n d −1ðÞX W 2i u ;t h ið5Þwhere W i d ;t and W i u ;t are the firm-speci fic returns for down-and up-weeks,respectively,and n d and n u are the numbers of down-and-up weeks,respectively.Higher values of NCSKEW and DUVOL indicate higher levels of crash risk.Table 2Descriptive statistics:This table presents the descriptive statistics of firm-and industry-level variables (panel A),information environment variables (panel B),and country-level variables (panel C).The sample period is from 1989to 2013.Summary statistics in panel A are based on a panel of firm-year observations,in panel B based on a cross section of countries,and in panel C based on a panel of country-year observations.All the variables are de fined in Appendix A .Panel A:Firm-and industry-level variablesN Mean Std.dev.Min.Max.[1][2][3][4][5]Leverage and crash-risk measures:BL 120,7640.210.180.00 1.00ML 120,7640.260.250.00 1.00BL_P 106,3360.220.20−2.68 2.46CRASH 120,7640.130.330.00 1.00NCSKEW 120,744−0.160.72−6.59 6.45DUVOL120,744−0.100.35−2.422.46Firm-and industry-level variables used in Eq.(1):Size a120,76412.90 1.88 5.4918.96Tang 120,7640.310.220.000.99MTB a120,764 1.28 1.310.0845.91Prof 120,7640.090.14−0.890.68Dep 120,7640.040.030.000.35Rd 120,7640.020.050.000.58Rd_dum 120,7640.450.500.00 1.00IndMed(B)120,7640.190.110.000.79IndMed(M)120,7640.230.160.000.97IndMed(B_P)120,7640.180.110.000.99Firm-level variables used in Eq.(6):Dturn 120,7640.000.13−37.530.46Sigma 120,7640.050.020.000.27Ret 120,764−0.140.16−3.290.00Size e120,76412.48 1.96 4.8318.15MTB e120,764 2.30 3.460.08110.65LD 120,7640.120.140.000.78ROA 120,7640.030.13−0.910.73ACCM 120,7640.80 2.590.0284.72Panel B:Information environment variables AccStd 3771.868.1756.0085.00Analyst 3714.447.99 2.4032.40FinTra 360.250.76−1.39 1.62Audit 36 3.22 1.02 1.00 4.00InfDis363.06 1.16 1.20 6.40Panel C:Country-level variables GDPC 7439.58 1.23 6.2111.12MCAP 74387.4072.57 6.84606.00GGDP743 3.31 3.40−13.1315.24137Z.An et al./Journal of Corporate Finance 31(2015)132–1513.3.Crash-risk exposureThe recent literature on crash risk suggests that firm-speci fic crash events can be predicted by firm-level accounting variables (Kim et al.,2011a ).To measure a firm's exposure to crash risk,we regress its crash-risk measure on a set of lagged factors:CR j ;i ;t ¼αj þδj Z j ;i ;t −1þy j ;t þe j ;i ;t ;ð6Þwhere Z j,i,t −1is a vector of firm-level characteristics,including detrend turnover (Dturn ),negative skewness (NCSKEW ),standard de-viation and mean of the firm-speci fic weekly return (Sigma and Ret ),firm size (Size e ),market-to-book ratio (MTB e ),long-term debt ratio (LD ),return on asset (ROA ),and earning opacity (ACCM ).We use a logit model to estimate future crash event probability (CRASH )and linear models to predict future return asymmetry (NCSKEW and DVUOL ).Eq.(6)is estimated by country to allow heterogeneous coef ficient estimators across countries.We denote the fitted value of Eq.(6)by ĈR j ,i ,t +1and use it as a proxy for a firm's exposure to crash risk:^CR j ;i ;t ¼^αj þ^δZ j ;i ;t −1þ^y j ;t :ð7Þ3.4.Partial adjustment toward targetFinally,we estimate a partial adjustment model of capital structure:L j ;i ;t −L j ;i ;t −1¼α0þλj ;i ;t −1TL j ;i ;t −L j ;i ;t −1þu j ;i ;t ;ð8Þwhere λj ,i ,t −1is a measure of SOA and depends upon crash-risk exposure:λj ;i ;t −1¼β0þβ1^CR j ;i ;t þγX j ;i ;t −1þηY j ;t −1:ð9ÞOur first hypothesis suggests that β1b 0.Table 3Correlation matrix:Panel A provides the correlation matrix for pairs of firm-,industry-level variables in the target leverage model (i.e.,Eq.(1)).Panel B provides the correlation matrix for pairs of firm-level variables in the crash prediction model (i.e.,Eq.(6)).All variables are de fined in Appendix A .Panel A:Target leverage model[1][2][3][4][5][6][7][8][9][10][11][12][13]BL [1] 1.00ML [2]0.83 1.00BL_P [3]0.910.76 1.00Size a [4]0.260.220.21 1.00Tang [5]0.290.240.250.12 1.00MTB a [6]−0.17−0.34−0.16−0.12−0.12 1.00Prof [7]−0.04−0.09−0.080.240.090.06 1.00Dep [8]0.05−0.020.04−0.020.260.020.13 1.00R&D[9]−0.18−0.23−0.14−0.13−0.240.28−0.320.08 1.00R&D_dum [10]0.090.110.09−0.100.16−0.080.03−0.04−0.35 1.00IndMed(B)[11]0.400.410.340.200.27−0.210.15−0.02−0.320.14 1.00IndMed(M)[12]0.340.460.300.180.23−0.300.07−0.07−0.290.090.84 1.00IndMed(B_P)[13]0.400.430.350.190.27−0.230.14−0.02−0.330.150.980.851.00Panel B:Crash prediction model[1][2][3][4][5][6][7][8][9][10][11]CRASH [1] 1.00NCSKEW [2]0.55 1.00DUVOL [3]0.500.95 1.00Dturn [4]0.000.000.00 1.00Sigma [5]0.000.00−0.010.00 1.00Ret [6]0.00−0.010.00−0.01−0.96 1.00Size e [7]0.030.130.140.00−0.420.37 1.00MTB e [8]0.050.060.060.000.06−0.070.21 1.00LD [9]0.000.020.020.00−0.040.040.180.06 1.00ROA [10]0.010.020.030.00−0.350.340.280.01−0.05 1.00ACCM[11]0.030.020.020.000.15−0.16−0.030.070.00−0.061.00138Z.An et al./Journal of Corporate Finance 31(2015)132–151。
人工智能对人类的影响英语作文
Artificial intelligence AI has been a subject of fascination and concern for many decades.As we stand on the brink of a new era where AI is becoming increasingly integrated into our daily lives,it is crucial to consider the profound impact it will have on humanity.1.Economic Impact:The integration of AI into various industries has the potential to significantly alter the economic landscape.Automation powered by AI can increase productivity,reduce costs, and create new job opportunities in fields such as data analysis and AI development. However,it also poses the risk of job displacement for workers in sectors that are heavily reliant on manual labor or routine tasks.2.Social Implications:AI has the power to reshape social interactions.For instance,AIpowered social media algorithms can influence the information we consume,shaping our opinions and beliefs. This raises ethical questions about the control of information and the potential for manipulation.3.Healthcare Advancements:In the medical field,AI is revolutionizing diagnostics,treatment plans,and patient care. AI can analyze vast amounts of medical data to detect patterns that may be invisible to the human eye,leading to earlier and more accurate diagnoses.This can save lives and improve the overall quality of healthcare.cation Transformation:AI can personalize education by adapting to individual learning styles and paces.This can lead to more effective learning experiences and potentially bridge educational gaps. However,it also raises concerns about the role of human teachers and the potential for AI to exacerbate educational inequalities if not implemented equitably.5.Ethical and Moral Considerations:As AI becomes more autonomous,ethical dilemmas arise.Questions about AIs decisionmaking processes,accountability,and the potential for bias in AI algorithms are critical.Ensuring that AI systems are designed with fairness,transparency,and respect for human rights is essential.6.Security and Privacy Concerns:The use of AI in surveillance and data collection raises significant privacy concerns. While AI can enhance security by detecting threats and anomalies,it also has the potential to infringe upon personal freedoms if not regulated properly.7.Environmental Impact:AI can contribute to environmental conservation by optimizing resource use,monitoring ecosystems,and predicting natural disasters.However,the energy consumption of AI systems,particularly in data centers,is a growing concern that needs to be addressed to minimize the carbon footprint.8.Creative and Cultural Shifts:AIs ability to generate art,music,and literature challenges our understanding of creativity and authorship.This can lead to new forms of cultural expression but also raises questions about the value and authenticity of AIgenerated content.9.Legal and Regulatory Challenges:As AI systems become more complex,the legal framework must evolve to address issues such as liability,intellectual property rights,and the rights of AI entities.This is an ongoing challenge for lawmakers and policymakers.10.Future of HumanAI Interaction:The future of AI will likely involve more seamless interaction between humans and machines.This could lead to a symbiotic relationship where AI augments human capabilities,but it also requires careful consideration of the boundaries and responsibilities of each entity.In conclusion,the impact of AI on humanity is multifaceted and farreaching.It offers immense potential for progress but also presents significant challenges that must be navigated with caution and foresight.As we move forward,it is imperative that we engage in a global dialogue to shape the development of AI in a way that benefits all of humanity while mitigating potential risks.。
成人高考英语试卷文科类
Part I Listening Comprehension (20 points)Section A (5 points)In this section, you will hear five short conversations. After each conversation, there will be a question. Both the conversation and the question will be spoken only once. Listen carefully and choose the best answer from the four choices given.1. A. He will attend the meeting. B. He will go to the library. C. He will go to the doctor. D. He will finish the report.2. A. She will help him with the assignment. B. She will do the assignment for him. C. She will not help him. D. She will ask someone else to help him.3. A. He will go to the concert. B. He will go to the movie. C. He will stay at home. D. He will visit his friend.4. A. She will have a vacation. B. She will continue her studies. C. She will change her major. D. She will find a new job.5. A. She will cook dinner. B. She will go shopping. C. She will clean the house. D. She will watch TV.Section B (15 points)In this section, you will hear three short passages. After each passage, there will be some questions. Both the passage and the questions will be spoken only once. Listen carefully and choose the best answer from the four choices given.Passage 1Questions 6 to 8 are based on the passage you have just heard.6. What is the main topic of the passage?A. The importance of exercise for health.B. The benefits of playing sports.C. The negative effects of sedentary lifestyle.D. The history of sports.7. According to the speaker, what is the most effective way to stay healthy?A. Regular exercise.B. Eating a balanced diet.C. Getting enough sleep.D. Reducing stress.8. Why is it important to exercise regularly?A. It helps to maintain a healthy weight.B. It improves mental health.C. It reduces the risk of chronic diseases.D. All of the above.Passage 2Questions 9 to 11 are based on the passage you have just heard.9. What is the main idea of the passage?A. The history of the Internet.B. The impact of the Internet on society.C. The benefits of the Internet in education.D. The challenges of the Internet.10. According to the passage, how has the Internet changed our lives?A. It has made communication easier.B. It has created new job opportunities.C. It has provided access to a vast amount of information.D. All of the above.11. What is the author's opinion about the Internet?A. It has more benefits than challenges.B. It has more challenges than benefits.C. It is both beneficial and challenging.D. It is not beneficial at all.Passage 3Questions 12 to 15 are based on the passage you have just heard.12. What is the passage mainly about?A. The effects of climate change on wildlife.B. The efforts to protect endangered species.C. The importance of biodiversity.D. The challenges of conservation.13. According to the speaker, what is the main threat to biodiversity?A. Habitat destruction.B. Pollution.C. Overfishing.D. All of the above.14. What is one of the solutions proposed to address the issue of biodiversity loss?A. Establishing protected areas.B. Promoting sustainable agriculture.C. Raising awareness about the importance of conservation.D. All of the above.15. What is the author's main message in the passage?A. The need for immediate action to protect biodiversity.B. The importance of scientific research in conservation efforts.C. The role of governments in protecting the environment.D. The responsibility of individuals in conservation.Part II Structure and Vocabulary (30 points)Section A (15 points)In this section, there are 15 incomplete sentences. Each sentence has a blank in it. Choose the word or phrase that best completes the sentence.16. I am sure that he ________ (pass) the exam if he had studied harder.A. would passB. will passC. passedD. has passed17. ________ (be) a teacher is not an easy job.A. To becomeB. BecomingC. BecomeD. Becomes18. ________ (not to) smoke is a good habit.A. NotB. Not toC. Not doingD. Not doing to19. He ________ (finish) his work by the end of the month.A. hasB. hadC. haveD. had had20. ________ (you) to come to the meeting?A. DidB. DoC. AreD. Were21. She ________ (go) to the party last night, but she was too tired.A. wouldB. shouldC. couldD. might22. ________ (you) to finish the project by the end of the week?A. AreB. IsC. WereD. Will23. ________ (be) a doctor is his dream.A. To becomeB. BecomingC. BecomeD. Becomes24. He ________ (be) late for the meeting, but he had an accident on his way.A. wasn'tB. doesn'tC. didn'tD. hasn't25. ________ (you) to come with me?A. WouldB. Would youC. Would you likeD. Would you beSection B (15 points)In this section, there are 15 sentences. Some of them are correct and some are incorrect. Choose the correct sentences and write the letter of the correct sentence in the corresponding blank.26. The Earth's atmosphere is made up of different gases, including nitrogen, oxygen, and carbon dioxide.A. CorrectB. Incorrect27. The solar system consists of the sun, eight planets, and numerous moons and asteroids.A. CorrectB. Incorrect28. Water is a polar molecule, which means it has a positive and a negative end.A. CorrectB. Incorrect29. The human brain is responsible for processing information, making decisions, and controlling movements.A. CorrectB. Incorrect30. The Great Wall of China is one of the most famous landmarks in the world and is a symbol of Chinese culture.A. CorrectB. Incorrect31. The Olympic Games are held every four years and feature competitions in various sports.A. CorrectB. Incorrect32. Renewable energy sources, such as solar and wind power, are becoming increasingly popular as alternatives to fossil fuels.A. CorrectB. Incorrect33. The human body consists of approximately 70% water, which is essential for many bodily functions.A. CorrectB. Incorrect34. The digestive system breaks down food into nutrients that the body can use for energy and growth.A. CorrectB. Incorrect35. The Amazon rainforest is the largest tropical rainforest in the world and is home to a vast array of plant and animal species.A. CorrectB. IncorrectPart III Reading Comprehension (40 points)Section A (20 points)Read the following passage and answer the questions that follow.The Renaissance was a period of great cultural change and achievement that took place in Europe from the 14th to the 17th century. It was characterized by a revival of interest in the classical art, literature, and philosophy of ancient Greece and Rome. This period saw the rise of humanism, a movement that emphasized the importance of human potential and achievements. The Renaissance was also a time of significant scientific discoveries and technological advancements.One of the most influential figures of the Renaissance was Leonardo da Vinci, an Italian polymath who was a painter, sculptor, engineer, and inventor. His works, such as the Mona Lisa and The Last Supper, arestill celebrated today for their artistic excellence. In addition to his contributions to art, da Vinci also made significant contributions to science, including his studies on anatomy, flight, and hydrodynamics.Another important Renaissance figure was Michelangelo, an Italian sculptor, painter, and architect. His sculptures, such as David and The Pieta, are among the most iconic works of art. Michelangelo's architectural designs, including the dome of St. Peter's Basilica in Rome, also had a lasting impact on the field of architecture.The Renaissance had a profound impact on the world. It led to the development of modern science, the democratization of education, and the rise of the modern nation-state. The period also saw the beginning ofthe Age of Exploration, as European explorers set out to discover new lands and trade routes.Questions 36 to 40 are based on the passage.36. What was the main characteristic of the Renaissance?A. A focus on the importance of human potential.B. A revival of interest in classical art and literature.C. A period of significant scientific discoveries.D. All of the above.37. Who was one of the most influential figures of the Renaissance?A. MichelangeloB. Leonardo da VinciC. Both A and BD. None of the above38. What was Leonardo da Vinci known for besides being a painter?A. His contributions to science.B. His architectural designs.C. Both A and BD. None of the above39. What was one of the impacts of the Renaissance?A. The development of modern science.B. The democratization of education.C. The rise of the modern nation-state.D. All of the above.40. What was the period of the Renaissance characterized by?A. A revival of interest in classical art and literature.B. A focus on the importance of human potential.C. A period of significant scientific discoveries.D. All of the above.Section B (20 points)Read the following passage and answer the questions that follow.Globalization has transformed the world in numerous ways, but one of the most significant impacts has been on the environment. The increased movement of goods and people across borders has led to a rise in carbon emissions and pollution. However, globalization has also brought about technological advancements and innovations that can help mitigate these negative effects.One of the major environmental challenges of globalization is climate change. The burning of fossil fuels for transportation and energy production has led to a rise in greenhouse gas emissions, which contribute to global warming. To address this issue, many countries have implemented policies to reduce their carbon footprint, such as investing in renewable energy sources and promoting energy efficiency.Another environmental impact of globalization is the loss of biodiversity. The expansion of agriculture, deforestation, and urbanization have led to the destruction of natural habitats and the extinction of many species. Efforts to protect biodiversity include establishing protected areas, promoting sustainable land use practices, and conducting research to understand the impacts of human activities on ecosystems.Despite these challenges, globalization has also brought about opportunities to address environmental issues. The increased flow of information and technology has enabled countries to share knowledge and resources, leading to the development of new solutions to environmental problems. For example, the Internet has facilitated the exchange ofinformation on climate change and has helped raise awareness about the need for action.Questions 41 to 45 are based on the passage.41. What is one of the environmental challenges of globalization?A. Climate changeB. Loss of biodiversityC. Both A and BD. None of the above42. What is one way countries are addressing the issue of climate change?A. Investing in renewable energy sourcesB. Promoting energy efficiencyC. Both A and BD. None of the above43. What is one of the negative impacts of globalization on the environment?A. The destruction of natural habitatsB. The expansion of agricultureC. Both A and BD. None of the above44. What has the Internet facilitated in the context of environmental issues?A. The exchange of information on climate changeB. The development of new solutions to environmental problemsC. Both A and BD. None of the above45. What is the overall impact of globalization on the environment?A. NegativeB. PositiveC. Both negative and positiveD. None of the abovePart IV Writing (20 points)Write an essay on the following topic:"The Role of Education in Personal Development"You should write at least 200 words. Your essay should include the following points:- The importance of education in shaping one's personality and skills.- How education can help individuals achieve their goals and aspirations.- The benefits of lifelong learning in today's rapidly changing world.[Your Answer Here]。
信管外文翻译
建立信息管理系统在行政管理机构信息是个重要资源。
及时有效的重要信息对于高效管理职能的表现是至关重要的,例如准备,组织,领导,控制。
在一个管理机构中,信息系统就像是人体中的神经系统,它把组织的所有元件连接在一起而且还在竞争的环境中提供更好的操作和生存机会。
信息系统经常提及一个以计算机为基础的,被设计成支持组织的操作、经营和决策功能的系统。
在组织中信息系统为决策者提供信息支持。
信息系统包含交易处理系统、管理信息系统、决策支持系统和战略的信息系统。
信息由经过处理的而且是对用户是有用的数据组成。
一个系统是为了达成一个共同的目的共同操作的一组元件。
因此一个管理信息系统收集,传送,处理,储存,而且在组织资源、程序表和成就上储存数据。
系统进入经营信息之内为这些数据做合理的变换为决策者在组织里面的使用。
因此,一个管理信息系统提供支持组织管理职能的信息。
一、基本的概念1、数据和信息的比较数据提供未加工的、不被评估的事实数据、符号、物件、事件等等。
数据可能是一个在于储存事实的集合物件,像一个电话目录或者实施统计调查记录。
信息是那些已经进入一个有意义的,有用的背景而且传达到一个使用它做出决断的接受人的数据。
信息涉及智慧或知识的交流和接受。
它评价而且通知,吃惊而且刺激,减少不确定,现实另外可供选择的方案或者帮助去除无关的或者没用的信息,还影响人们并且鼓励他们做出行动。
数据的元素在一个特殊的背景下可能构成一条信息;例如,当你想联系你的朋友的时候,他或者她的电话号码就是一条信息;除此之外,它在电话号码薄里仅仅是一个数据的元素。
2、信息的特性好信息的特性是中肯的、时间性、准确性、成本效益、可靠性、可用性、无遗漏和凝聚层次。
如果它引导改良的决策,信息是有关的。
如果它重新确定之前的决定它也是有关的。
如果它对你的问题没有任何帮助那它就是无关的。
例如,如果你在一月考虑去巴黎,那有关巴黎一月的天气情况的信息对你来说就是有关的。
否则,这信息就是无关的。
Unit 1 Integrated skills 课件 高中英语牛津译林版选择性必修第三册
world heritage list by UNESCO and therefore deserve your visit too.
The above mentioned places are characteristic of ancient Chinese buildings with Suzhou style, and I sincerely hope you can come and visit
Central Business District of Suzhou Industrial Park depends towering buildings and splendid scenery
3. 如何结尾
阐述此趟旅游的意义
The trip was greeted with massive credit. Not only have we gained a deeper insight into Suzhou city, it has also involved us in appreciation, further enhancing artistic education.
预测一 假定你是李华,你的外国笔友Chris来信表示下周计划来你的家乡旅 游三天并希望你担任他的导游。请你给他回信,内容包括:1.表示 欢迎;2.简单介绍你的家乡;3.告知行程安排。
如何布局文章?
第一段:表示欢迎 第二段:家乡简介 第三段:告知行程安排
第一段:表示欢迎 第二段:家乡简介+告知行程安排 第三段:再次欢迎/总结
√the third day
国际原子能组织介绍
Its Framework Jing Zhang
TCEU, IAEA August, 2012
IAEA
International Atomic Energy Agency
IAEA Organizational Chart
DIRECTORGENERAL Yukiya Amano
•
•
IAEA
IAEA Medium Term Strategy 2012-2017
Six strategic objectives
• Facilitating access to nuclear power • Strengthening promotion of nuclear science, technology and applications • Improving nuclear safety and security • Providing effective technical cooperation • Strengthening the effectiveness and improving the efficiency of the Agency’s safeguards and other verification activities • Providing effective, innovative management and strategic planning.
IAEA
10
I. NPT-IAEA safeguards (control)
The NPT, or the Treaty on the Non-Proliferation of Nuclear Weapons
体验商务英语3unit1Globalization
1-5
The Globalization of Markets
The globalization of markets refers to the merging of historically distinct and separate national markets into one huge global marketplace.
economies with high barriers to crossborder trade and investment a move toward a more integrated global economic system with lower barriers to trade and investment about $3 trillion in foreign exchange transactions taking place everyday the establishment of international institutions
1-11
Declining Trade and Investment Barriers
Lower trade barriers enable companies to view the world as a single market and establish production activities in optimal locations around the globe
The goal for companies is to lower their overall cost structure or improve the quality or functionality of their product and gain competitive advantage
2023年9月综a大作文
2023年9月综a大作文英文回答:In the face of burgeoning global challenges, it is imperative for individuals to assume a proactive and collaborative approach in addressing them. As conscientious members of society, we must transcend narrow self-interest and prioritize collective well-being. This requires embracing a cosmopolitan outlook that recognizes our interconnectedness and shared responsibility for shaping a better future.By fostering empathy and understanding, we can bridge cultural divides and establish common ground. Compassionand solidarity should guide our interactions, enabling usto transcend personal differences and work harmoniously towards shared objectives. Through dialogue and cooperation, we can build a truly global community where diversity is celebrated and inclusivity reigns supreme.Moreover, it is essential to cultivate criticalthinking and scientific literacy. In an era of rampant misinformation and disinformation, it is vital to access and analyze information from credible sources. By questioning assumptions, examining evidence, and engaging in informed discourse, we can make sound judgments and contribute to evidence-based decision-making.Education plays a pivotal role in empoweringindividuals to become responsible global citizens. Curricula should emphasize global issues, fostering awareness and encouraging students to develop a sense of purpose. By nurturing critical thinking, problem-solving abilities, and communication skills, education can equip individuals with the tools necessary to navigate the complexities of a globalized world.Furthermore, it is crucial for governments and international organizations to work in tandem to address global challenges. Collaborative efforts, such as the Sustainable Development Goals, provide a framework for addressing pressing issues such as inequality, poverty, andclimate change. By pooling resources and expertise, we can amplify our collective impact and create a more just and equitable world.中文回答:在全球挑战不断涌現的背景下,個人必須積極主動地採取合作方式來應對這些挑戰。
2024年6月英语四级考试试卷
2024年6月英语四级考试试卷一、写作(15%)题目: The Importance of Lifelong Learning。
要求:1. 阐述终身学习的重要性;2. 给出如何进行终身学习的建议;3. 字数不少于120字。
二、听力理解(35%)Section A(7.1%)Directions: In this section, you will hear three news reports. At the end of each news report, you will hear two or three questions. Both the news report and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A), B), C) and D).News Report 1.1. A) A new scientific discovery.B) A major earthquake.C) A new government policy.D) A large - scale cultural event.Question 1: What is the news report mainly about?Question 2: How will it affect the local area?News Report 2.2. A) To promote international trade.B) To improve environmental protection.C) To enhance cultural exchange.D) To develop new technologies.Question 1: What is the purpose of the new initiative?Question 2: Which countries are expected to participate?News Report 3.3. A) A famous athlete's retirement.B) A sports event's new record.C) A sports team's reorganization.D) A sports facility's opening.Question 1: What is the main topic of this news?Question 2: What are the expectations for the future?Section B(14.2%)Directions: In this section, you will hear two long conversations. At the end of each conversation, you will hear four questions. Both the conversation and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A), B), C) and D).Conversation 1.1. A) Discussing a study plan.B) Planning a vacation.C) Talking about a job interview.D) Arranging a party.Question 1: What are the two speakers mainly doing?Question 2: What is the man's opinion about the first option? Question 3: What does the woman suggest?Question 4: When will they make a final decision? Conversation 2.2. A) A new movie.B) A best - selling book.C) A popular music concert.D) An art exhibition.Question 1: What are they talking about?Question 2: What does the man like about it?Question 3: What is the woman's attitude towards it? Question 4: Are they going to experience it together?Section C(14.2%)Directions: In this section, you will hear three passages. At the end of each passage, you will hear three or four questions. Both the passage and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A), B), C) and D).Passage 1.1. A) The history of a city.B) The development of a technology.C) The origin of a custom.D) The growth of a plant.Question 1: What is the passage mainly about?Question 2: What are the key factors in its development?Question 3: How has it influenced people's lives?Passage 2.2. A) Different types of diets.B) Ways to keep healthy.C) The importance of exercise.D) Common health problems.Question 1: What is the general topic of this passage?Question 2: Which method is most recommended?Question 3: What should people avoid?Passage 3.3. A) A famous historical figure.B) An important historical event.C) A unique cultural heritage.D) A remarkable architectural wonder.Question 1: What does the passage focus on?Question 2: What are its special features?Question 3: How can people preserve it?三、阅读理解(35%)Section A(10%)Directions: In this section, there is a passage with ten blanks. Youare required to select one word for each blank from a list of choices given in a word bank following the passage. Read the passage through carefully before making your choices. Each choice in the bank is identified by a letter. Please mark the corresponding letter for each item on Answer Sheet 2. You may not use any of the words in the bank more than once.Passage.The Internet has changed the way we communicate, work, and learn. Ithas brought great convenience to our lives. However, it also has some _(1)_ problems. One of the major issues is the spread of false information. With the click of a mouse, false news can be _(2)_ all over the world in seconds. This can cause panic, mislead the public, and even _(3)_ social stability. Another problem is the invasion of privacy. Many websites collect users' personal information without their _(4)_, and sometimes this information is sold to other companies for profit. In addition, the Internet can also be aplatform for cyberbullying, which can have a _(5)_ impact on the mental health of victims.Word Bank:A) negative.B) positive.C) widespread.D) consent.E) undermine.F) promote.G) restricted.H) transmitted.I) serious.J) minor.Section B(10%)Directions: In this section, you are going to read a passage with ten statements attached to it. Each statement contains information given in one of the paragraphs. Identify the paragraph from which the information is derived. You may choose a paragraph more than once. Each paragraph is marked with a letter. Answer the questions by marking the corresponding letter on Answer Sheet 2.Passage.The Benefits of Reading Aloud.(A) Reading aloud has been a traditional way of learning for a long time. It not only helps with pronunciation but also improves memory. When we read aloud, we engage more of our senses. We see the words, hear our own voices, and feel the rhythm of the language. This multi - sensory experience can enhance our understanding and retention of the text.(B) For children, reading aloud is especially beneficial. It can stimulate their interest in reading. When parents or teachers read aloud to children, they can use different voices and intonations to bring the story to life. This can make the reading experience more enjoyable and exciting for children, thus encouraging them to explore more books on their own.(C) Reading aloud can also be a form of self - expression. It allows us to convey our emotions and thoughts more vividly. Whether it is a poem, a speech, or a passage from a novel, reading it aloud gives us the opportunity to add our own interpretation and personality to the words.(D) In a group setting, reading aloud can promote communication and cooperation. For example, in a classroom, students can take turns reading parts of a text. This can help them learn from each other, share different perspectives, and build a sense of community.(E) Another advantage of reading aloud is that it can improve ourpublic speaking skills. By practicing reading aloud regularly, we can become more confident in speaking in front of others. We can learn to control our voice, pace, and intonation, which are all important elements of effective public speaking.Statements:1. Reading aloud helps with pronunciation and memory.2. Reading aloud can make reading more interesting for children.3. Reading aloud is a way to express oneself vividly.4. Reading aloud in a group can enhance communication.5. Reading aloud can help improve public speaking skills.Section C(15%)Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A), B), C) and D). You should decide on the best choice and mark the corresponding letter on Answer Sheet 2.Passage 1.The Impact of Social Media on Youth.Social media has become an integral part of the lives of today's youth. It offers a platform for them to connect with friends, share their experiences, and express their opinions. However, it also has a number of negative impacts.One of the concerns is the excessive time that youth spend on social media. Many young people are addicted to scrolling through their social media feeds, which can lead to a decrease in their productivity. They may neglect their studies, hobbies, or real - life social interactions.Another issue is the negative influence on self - esteem. Social media often presents an idealized version of life. Youth may compare themselves to others and feel inadequate when they see the seemingly perfect lives of their peers on social media. This can lead to feelings of low self - worth and even depression.Moreover, the spread of false information on social media can mislead youth. They may believe in untrue news or rumors without verifying the sources, which can have a negative impact on their decision - making abilities.1. What is the main idea of this passage?A) The positive aspects of social media for youth.B) The negative impacts of social media on youth.C) How youth can make the best use of social media.D) The popularity of social media among youth.2. Why are youth addicted to social media according to the passage?A) Because it helps them with their studies.B) Because it offers a lot of useful information.C) Because they can connect with friends and share experiences.D) Because they want to improve their self - esteem.3. How can social media affect youth's self - esteem?A) By providing real - life examples.B) By presenting an idealized version of life.C) By offering positive feedback.D) By promoting real - life social interactions.4. What is the consequence of believing in false information on social media?A) An increase in productivity.B) A positive impact on decision - making abilities.C) A negative impact on decision - making abilities.D) An improvement in self - esteem.Passage 2.The Future of Renewable Energy.Renewable energy sources such as solar, wind, and hydro power are becoming increasingly important in the global energy mix. The development of these energy sources is driven by the need to reduce carbon emissions and combat climate change.Solar power has seen significant growth in recent years. The cost of solar panels has decreased, making it more accessible for households and businesses. With the improvement of technology, the efficiency of solar power generation has also increased.Wind power is another major renewable energy source. Large - scale wind farms are being built around the world. The development of offshore wind farms is also on the rise, as they can generate a large amount ofelectricity with less impact on the land environment.Hydro power has a long history of use. However, the construction of new hydro power plants needs to consider environmental and social impacts more carefully.Despite the progress made in renewable energy, there are still some challenges. For example, the intermittency of solar and wind power requiresthe development of energy storage technologies. The initial investment in renewable energy projects can also be high.1. What is the main driving force behind the development of renewable energy?A) To increase energy consumption.B) To reduce carbon emissions and combat climate change.C) To make energy more expensive.D) To promote economic development.2. What has made solar power more accessible?A) The increase in its efficiency.B) The decrease in the cost of solar panels.C) The improvement of technology.D) The construction of large - scale solar farms.3. Why is the development of offshore wind farms on the rise?A) Because they are cheaper to build.B) Because they can generate more electricity.C) Because they have less impact on the land environment.D) Because they are easier to manage.4. What are the challenges in the development of renewable energy?A) The high cost of energy storage technologies.B) The intermittency of solar and wind power and high initial investment.C) The lack of government support.D) The competition from traditional energy sources.四、翻译(15%)题目:中国的城市化(urbanization)将会充分释放潜在内需(domestic demand)。
方案整合英文
Document Title: Integrated SolutionsIntroductionIn today's fast-paced and competitive business environment, companies seek innovative ways to enhance efficiency, streamline operations, and achieve sustainable growth. One approach that has gained significant attention is the integration of various systems and strategies within an organization. This document explores the concept of integrated solutions, their benefits, andthe steps involved in implementing such solutions.I. What are Integrated Solutions?Integrated solutions refer to the combination of various systems, processes, and strategies within a company to create a seamless and interconnected framework. This integration allows for data sharing, improved communication, and enhanceddecision-making across different departments and functions.II. Benefits of Integrated Solutions1. Enhanced Efficiency: Integrated solutions eliminate redundancy and streamline processes, resulting in improved productivity and reduced operational costs. Automation and synchronized data ensure that information flows seamlessly between different systems, reducing thelikelihood of human error and eliminating the need for manual data entry.2. Improved Decision-Making: Integrated solutions provide organizations with a holistic view of their operations, enabling better decision-making. Real-time data integration allows for accurate and up-to-date information, empowering managers tomake informed decisions quickly and effectively.3. Increased Customer Satisfaction: Integrated solutions enable companies to have a unified view of their customers, ensuring consistent and personalized interactions at every touchpoint. Through integrated customer relationship management (CRM) and enterprise resource planning (ERP) systems, businesses can enhancecustomer service, tailor offerings, and improve overall customer satisfaction.4. Scalability and Growth: Integrated solutions provide a solid foundation for scalable growth. By combining various systems and strategies, organizations are better equipped to adapt to changing market conditions, expand into new markets, and introduce new products or services.III. Steps to Implement Integrated SolutionsImplementing integrated solutions requires careful planning, coordination, and collaboration among different stakeholders. The following steps can guide organizations in successfully integrating their systems and strategies:1. Assess Current Systems: Evaluate existing systems, processes, and technologies to identify gaps and areasin need of improvement. Determine the specific goals and objectives that the integrated solutions should address.2. Define Requirements: Clearly define the requirements and functionalities that the integrated solutions should have. Identify the key stakeholders and involve them in the decision-making process to ensure that all relevant needs and perspectives are considered.3. Choose the Right Solution: Conduct comprehensive research to identify suitable solutions that align with the organization's requirements. Consider factors such as scalability, ease of integration, vendor support, and cost-effectiveness.4. Plan Implementation: Develop a detailed implementation plan that outlines the necessary steps, timelines, and responsibilities. Consider potentialrisks and develop contingency plans to minimize disruption during the transition.5. Integration and Testing: Begin integrating the chosen solutions into the existing systems. Ensure that data integration is seamless and that all processes and functionalities work as intended. Conduct rigorous testing to identify and resolve any issues or glitches.6. Training and Change Management: Provide adequate training to employees on using the integrated solutions effectively. Additionally, focus on change management to ensure smooth adoption and acceptance of the new systems and processes.7. Monitor and Improve: Regularly monitor the performance of the integrated solutions and gather feedback from users. Continuouslyanalyze metrics and make necessary adjustments to optimize efficiency and address any emerging challenges.ConclusionIntegrated solutions offer organizations a multitude of benefits, including enhanced efficiency, improved decision-making, increased customer satisfaction, and scalability for future growth. By carefully assessing existing systems, defining requirements, andfollowing a well-planned implementation process, organizations can successfully integrate their systems and strategies, paving the way for increased competitiveness and sustained success.。
Globalization.-英语版全球化PPT
4
Tourism globalization
Tourism plays an important role in the process of economic globalization.
Small scale, single structure, has not yet developed into a complete system of industry
take concerted action .
Nowadays,internati nal tourism is the biggest industry in the world.Unfortunately ,international tourism creates tensio rather than undersanding between people from different cultures.
Advantages
It provides a chance for developing countries to meet opportunities and challenges.
Economic globalization can make the world's capital, technology, products, markets, resources, labor force reasonable configuration.
2
1
TEXT
ADD TEXT
Tang Bingtian
Tourism development has become international.
A The tourism industry in the modern world began to
2024年3月9日雅思作文题
2024年3月9日雅思作文题英文回答:Introduction.Technology has become an integral part of our lives, transforming the way we live, work, and interact with the world. Its impact on our society has been both positive and negative, leading to debates about its role in shaping our future.Benefits:1. Convenience and Efficiency: Technology has made our lives easier and more convenient. From smartphones to home automation systems, it has streamlined tasks, saved time, and improved productivity.2. Information Access: The Internet has granted us unprecedented access to information, making it easier forus to stay informed, pursue knowledge, and connect with people worldwide.3. Communication and Collaboration: Social media, messaging apps, and video conferencing have revolutionized communication, allowing us to stay connected with loved ones, collaborate on projects, and share ideas more effectively.4. Healthcare Advancements: Technology hassignificantly advanced healthcare by providing new diagnostic tools, treatment options, and remote patient monitoring systems.5. Economic Growth and Innovation: Technological advancements have driven economic growth by creating new industries, jobs, and opportunities for entrepreneurship and innovation.Challenges:1. Privacy Concerns: The vast amount of data collectedby technology raises concerns about privacy and data security. Companies and governments can potentially abuse this data for surveillance or commercial purposes.2. Social Isolation and Loneliness: While technology connects us in some ways, it can also lead to social isolation and loneliness. People may spend excessive time on screens, neglecting face-to-face interactions.3. Job Displacement: Automation and artificial intelligence (AI) have the potential to displace jobs in various industries, leading to unemployment and economic inequality.4. Addiction and Health Issues: Excessive technology use can lead to addiction, anxiety, and sleep problems. It can also contribute to physical health issues such as eye strain and musculoskeletal disorders.5. Environmental Impact: The production and disposal of electronic devices contribute to environmental pollution and resource depletion.Conclusion.Technology is a powerful tool that has both positiveand negative effects on our society. It offers convenience, information access, communication advancements, healthcare improvements, and economic growth. However, it also raises concerns about privacy, social isolation, job displacement, addiction, and environmental impact. As we embrace the benefits of technology, we must also address its challenges and work towards using it responsibly and ethically toshape a more equitable and sustainable future.中文回答:引言。
The International Economy and Globalization
– Shift from sail to steamships; Railways
– Driven by European and American businesses and individuals
11
Waves of Globalization
– Most developing countries
• Did not participate in the growth of global trade in manufacturing and services
– Continuing trade barriers in developed countries – Unfavorable investment climates – Antitrade policies in developing countries
5
What is Globalization
1. Coca-Cola vs. Pepsi 2. Ford vs. Toyota 3. Boeing vs. Airbus 4. Caterpillar vs. Komastu 5. General Electric vs. Rolls- Royce 6. Sony vs. Nintendo vs. Microsoft
– Significant international capital movements
19
Waves of Globalization
• Latest Wave of Globalization, began in 1980
– Some developing countries
• Competitive advantage in labor-intensive manufacturing
高级英语口语unit4概要
03
Analysis of Text Content
Analysis of Article Structure
Title
The title of the article should be a brief and catch summary of the main idea
Introduction
It examines the concept of globalization and its effects on different cultures around the world
Theme background introduction
Globalization is the process of interaction and integration among
own opinions clearly, and support their arguments with evidence
In this guidance, teachers should provide students with topics that are relevant to their interests and experiences This will resource them
The topic attention is the first attention in a paragraph and summarizes the main idea of that paragraph
Transition Attention
The transition attention links one paragraph to the next, creating a smooth flow of ideas
广西农村小学英语教育资源信息化建设的新思考
目录
• Design and implementation of information technology construction plan
• Evaluation and improvement of the effectiveness of information construction
lingua franca is becoming increasingly prominent.
English education resources in rural areas of China are relatively scarce and urgently need improvement.
Insufficient teaching resources
Single textbooks: Many rural primary school English textbooks have a single variety and outdated content, which cannot meet the needs of modern English education.
Insufficient teacher training
There are relatively few training opportunities for English teachers in rural primary schools, lacking systematic training plans and effective training resources, which is not conducive to the professional growth of teachers.
TPO71 综合口语听力文本
TD 托福综合口语听力文本Task2 Listening:Now listen to two students discussing the article.M: Hey, Molly. You play the violin, right? Did you see this article in today's paper? W: Yeah. And I'm looking forward to it. I really want to participate.M: Sounds like fun.W: Yeah, and it's a great opportunity, because the thing is, that each of us learns to play a lot of different pieces. But right now, there's only one concert given at the end of the year where students play. So, we each usually only get to play one piece at that concert.M: Oh, so you’re left having learned a lot of material that you never actually get the chance to perform.W: Right! So, it would be great to have more opportunities like this.M: I see your point.W: And I like the thing about the food, too. Because I think a lot of people, if they go, they'll be squeezing it in between classes, so they won't have time to eat lunch or anything before or after the concert.M: That's true, especially since the music building is way off by itself at the other end of campus, not close to any of the dining halls or the student center.W: Yeah, it's easily a 15-minute walk away, so this way people would still get something like to eat. It’s a really good idea.Task3 Listening :Now listen to part of a lecture on this topic in a Biology class.Well, A good example of this is shown in a scientific study involving whales, orca whales, which happened to be one of the largest whale species. Now, orcas have a very sharp sense of hearing that is absolutely vital to their existence. In fact, they make special sounds and listen to the sounds echoes to help them determine the location, shape and size of objects in their habitat, like food. In other words, an orca whale uses an echo system to gather information about its immediate surroundings. It makes a series of clicking sound, and the echoes from these clicking sounds help lead the whale to the location of its next meal. Now, in their research, scientists studied noises in an orca whale habitat off the west coast of Canada. The scientist focused on noise from boats using the same water way as the whales. These researchers wanted to learn about possible changes in the whale's behavior when the noise level from the boats increased. In the end, an increase in the level of environmental noise from the boats is believed to have blocked the transmission distance of the whales clicking sounds. Scientists noticed that the size of the area in which the whale searched for foodbecame smaller by up to 20 %. So, it appears that the whales ecosystems were not able to function fully. Basically, the whales couldn't gather as much Information about possible sources of food in their surroundings.Task4 Listening:Listen to part of a lecture from an education class.So, of course, part of what teachers do is offer their students feedback or comments on their work or performance. They praise them when they do something right or let them know if they are doing something wrong. And this feedback helps students improve their work in the future. Effective feed feedback, feedback that's more likely to help students improve has certain character. Let's talk about two characteristics of effective feedback.One characteristic of effective feedback is that it's properly time. Feedback should be given when students are still working on a particular task or skill and have opportunities to apply the feedback to practice the teacher’s suggestion on a similar assignment. For example, if there's an art teacher whose students have been working on paintings for an assignment, she should give them feedback on these paintings while the class is still studying painting. So, the students can actually try the painting techniques the teacher recommends.Another characteristic of effective feed is that it focuses on student’s work and not on the students themselves. When a teacher criticizes the students, they might feel bad about themselves, but they won't necessarily know what to do differently. But when feedback focuses on student’s work, they learn what to do in the future. For example, to go back to the art teach, let's say one of her students does a painting and the teacher thinks the colors in the painting don't look good. Well, instead of telling the student he’s a bad painter, the teacher might suggest different colors to use in the next painting.。
BAWDEN,DandROBINSON,LIntroductiontoInformation…
BAWDEN, D. and ROBINSON, L. Introduction to Information Sciences. London: Facet Publishing. 2012.224 pages. ISBN 978-1856048101. £47.45This book acts as an excellent primer setting the context for study in the area of Information Sciences. It provides an overview of all major topics, with references to key authors, and recent developments in the field, in addition to useful summaries at the end of each chapter. It provides the reader with a firm foundation in the subject, written in an accessible style.The fifteen chapters of this book examine the entire arena of Information Sciences; covering its historical development as a discipline and associated paradigms, the key concepts underpinning the discipline and its wider discourse, fundamental aspects including information organisation, information and digital literacy, research, and the future of the discipline.Clear definitions of key concepts are carefully explained, with reference to theorists and further reading. In addition current examples are used to illustrate key points, and to provoke thought in a variety of areas.The first chapter considers what Information Science actually is, viewing it as a wholly unique meta-discipline with resulting links to a variety of other disciplines. The broad and diverse topics of Information Science are considered, in addition to the historical development of the subject and related professional associations over the past few hundred years.A brief, albeit informative, chapter is provided on the history of information, and the interconnected nature of social, technological and academic developments on the world of information is considered. Interestingly, the authors point out that we are still largely operating in a Victorian information environment.In addition, there is a chapter that attempts to explore the ‘why’ of information science, considering the paradigms and philosophies that form the basis of our thinking.The concept of information, with a multiplicity of meanings, and a lack of consensus, often dependent on the underlying paradigm, is also explored. Concepts such as collection, ‘aboutness’, and information use are examined to help provide a foundation to our understanding.The ‘bread and butter’ of information science, information organisation, is a lso succinctly tackled.A chapter on digital literacy considers the concept of information literacy and what it means to be information literate, looking at how this then relates to the idea of digital literacy. The importance of this concept in the information world is rightly stressed, alongside a consideration of how such skills can be engendered in the information user._______________________________________________________________________________ B. Casselden 123Information Science research is discussed looking at the paradigms underpinning such research, and the methods of enquiry that exist for the information researcher. Useful examples of current research using a variety of methods are given, which will be of great value to the reader.Finally, the future of Information Science is examined by considering the predictions of history, which arguably although influential, have rarely become true reality. The authors clearly identify that such speculation, although interesting, is almost always wrong. One also has to be aware that the future of Information Science is not just technology driven, but impacted upon by economic, social, political and demographic factors. The next 20 years are briefly considered, from business as usual to developing into the ‘clouds’, and the authors end on a positive note – arguing that Information Science has a bright future, but inevitably will change in ways we simply cannot imagine.This book was an interesting read, and I can certainly see it being a useful start for anyone wishing to learn more about Information Sciences. Certainly, my Masters students would benefit from reading this prior to their studies – in order to gain a general overview of the concepts surrounding this discipline. It synthesises the discipline in a clear and succinct way – providing just enough information to use as a launch pad for further independent discovery.Biddy CasseldenSenior LecturerInformation SciencesNorthumbria University**************************.uk_______________________________________________________________________________ B. Casselden 124。
basic writing for integration
Information integration in Basic writing基础写作之信息整合I. Targets tasks:Ability Targets: To integrate related information in writing a job application.II. Learning Strategies: 1. Self study 2. CooperationⅢ. Learning guidance:1 认真审题:本节课学习写求职信,第一人称,现在时(有具体时间状语的除外)。
基础写作的基础就体现在话题的词汇运用、句子结构和时态的准确使用上。
2 信息整合:写作内容要全,需要把多个信息点整合到一句话里。
信息整合需要语法形式的多样性,如非谓语动词,并列句、定语从句、状语从句、名词性从句、倒装、强调结构等。
基础写作的“不”基础之处就体现在语法运用多样性综合运用上。
I V. Learning procedure.1. Pre-task1 --- Daily Reading:Read aloud, try to underline the well-written points and make some changes to improve the following passage. Share your opinion with the whole class.Mr. Moore, aged 34, is my math teacher and also a kind and lovely man who impresses me _______________________________________________________________________________ most. Mr. Moore tries various teaching methods in his classes. In his opinion students should _______________________________________________________________________________ not only know “what”, but also understand “why”, so he encourages us to think by ourselves _______________________________________________________________________________ whenever he puts forward a question. With his help, we’ve learned how to analyze and solve _______________________________________________________________________________ problems. The classes of Mr. Moore are lively and interesting and we all admire him very much. _______________________________________________________________________________ Pre-task 2 ---Translation: Translate the following sentences , discuss in groups and share your improvements.Sentence 1(1)国际环保会议将于11月20日在我市召开。
Business Integration
Company B
Company AB
+
CEO
Common Functions Unique Functions
=
CEO
Common Functions Unique Functions
Unique Functions
7
Business integration (cont.)
批注本地保存成功开通会员云端永久保存去开通
Introductory Remarks
The impetus for change
Business Integration and IT Alignment
Meeting the challenge with Enterprise Architecture Dale Hunter (dale.hunter@.on.ca) Tony Brown (anthony.brown@)
• What is the Ontario Government doing?
6
What is business integration?
To integrate means to combine parts into a whole.
Business merger example:
Company A CEO
The environmness and e-Government Distributed systems Heterogeneous platforms and languages Legacy and open source and new code and off-the-shelf A need for inter-jurisdictional connectivity Wireless devices Privacy and security XML Financial constraints
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ALII: An information integration environment based on the active logic framework.A. A. Barfourosh1, H.R. Mothary Nezhad1, M. O’Donovan- Anderson2,D. Perlis2,31 Intelligent Systems Lab., Computer Engineering Dept., Amir Kabir University of Technology, Iran.2Institute for Advanced Computer Studies, University of Maryland,College Park, MD USA3 Department of Computer Science, University of Maryland, CollegePark, MD USAAbstractThere is growing interest in accessing, relating, and combining data from multiple sources on the Web. Enormous amounts of heterogeneous information have been accumulated within corporations, government organization and universities. Such information continues to grow at an ever-increasing rate. This information comes from different subject areas, and comes in different formats: bitmap, plain text, binary, etc.Today, web users access the web through two dominant interfaces: clicking on hyperlinks (browsing) and searching via keyword queries (crawling). This process is often time-consuming and unsatisfactory because of the many inaccurate and irrelevant results that are returned. Better support is needed for expressing one’s information requirements and dealing in more structured and syste matic ways with one’s search results. This paper presents ALII, our proposal for providing this support.ALII is an A ctive Logic based framework for Information Integration, which can utilize a compact context representation and constructs a hierarchy model of query and web pages. The ALII project aims developing methods and tools for a model based, semantic integration of information sources on web pages.Keywords: Web Information Retrieval, Focused Crawling, Active Logic.1IntroductionToday there i s growing interest in accessing, relating, and combining data from multiple sources. Enormous amounts of heterogeneous information have been accumulated within corporations, government organization and universities. Such information continues to grow at an ever-increasing rate. This information comes from different subject areas, and comes in different formats: bitmap, plain text, binary, etc.The World Wide Web is one such information resource, consisting of 1.5 billion pages covering different subjects and presented in different formats. As more information becomes available on the World Wide Web, it becomes more difficult toprovide effective tools for accessing this information. Today, web users access the web through two dominant interfaces: clicking on hyperlinks (browsing) and searching via keyword queries (crawling). This process is often time-consuming and unsatisfactory because of the many inaccurate and irrelevant results that are returned. Better support is needed for expressing one’s information requirements and dealing in more structured and systematic ways with one’s search results.Users have two main tools to help them locate relevant resources on the Web: Catalogs and Search Engines. Human experts construct catalogs. They tend to be highly accurate but can be difficult to maintain as the web grows. To keep up with this growth search engines were designed to eliminate human effort in cataloging web sites. A search engine consists of a mechanism that “crawls” the web looking for new or changed pages, an indexing mechanism and a query interface. Users generally query against the system index, although many contemporary search engines now also use link analysis to some degree. However, link analysis only helps to identify the most popular pages, and popularity may or may not correlate to relevance for a particular query.Let us use an example to illustrate some of the problems with web search. A reasonable search term might be “Artificial Intelligence Courses in Computer Science Departments in the USA”. As we can see, the result from the search engine is huge. Finding the proper set of results from this query from within the returned set is very time consuming. Some of the pages are not relevant and some others, which may be relevant, can only be found by following links several levels deep.It seems clear, then, that an automated system that could reason about the relevance of pages on the web to a given query would represent a significant advance in the accessibility and usability of the web. We propose Active Logic as a candidate for the reasoning engine of such a system. Active Logic is a formal architecture that is more closely tied to implementational constraints than is usual for formalisms, and which has been used to solve a number of commonsense problems in a unified manner. In particular, Active Logic seeks to apply theoretically justifiable, principled (logic-based) methods of reasoning to dynamic, uncertain—and to this extent real world—contexts. [2,3] Active Logic works by combining inference rules with a constantly evolving measure of time (a “Now”) that can itself be referenced in those rules. As an example, from Now (t)—the time is now “t”—one infers Now (t+1), for the fact of an inference implies that time (at least one ‘time-step’) has passed. All the inference rules in Active Logic work temporally in this way: at each time-step all possible one step inferences are made, and only propositions derived at time t are available for inferences at time t+1.In following sections, we study the existing problems in information integration and will propose an Active Logic based environment for Information Integration (ALII). In section 2 we describe the current research projects on information integration. In section 3 we review the u se of focused crawling to improve the efficiency of information integration systems. Section 4 consists of a brief introduction to active logic and introduces an Information Integration Environment based on Active Logic. Our conclusions are presented in section 5.2 Current Projects on Information Integration.There have been numerous attempts to improve the search engine. One of the major efforts in this regard is in improving Web Crawlers, also known as robots, spiders,worms, walkers, and wanderers. A crawler generally starts with some default web addresses, and downloads the specified document. For each page, it pulls out all of the addresses (links) contained within the page–it will search in breath-first-search manner later. It then indexes all of the words in that page, storing every word and phrase in that page in a database so the system can later search that database for a phrase that might exist in this page. Some other information is also stored about the page, e.g. the time when it was last downloaded, time when it was last updated, summary words, the title of the page, etc. Every word in that page is searchable by a user once it is saved to the database; this enables one to search for phrases or keywords in any document on the Internet.Note that the crawler pulls out all of the links within that page for future reference; this is where the "crawler" concept comes in. Theoretically, a web crawler could start with one page, grab all of the links from that page, search those pages in turn (thereby grabbing more links) and continue until it has searched all pages on the Internet. The problem with this strategy is clear: you can't get to all parts of the Internet from a single point. Some pages are entirely unreferenced, and there are pools of pages, which, although internally linked, are as a group not referenced elsewhere in the net. Further, the crawler sometimes isn't terribly smart about which "path" it takes in crawling the Internet. Web crawlers are typically automatic, with only a bit of hum an maintenance. As a result, the information is stored away as a bunch of keywords associated with the document, but no human summary or classification is available. This makes these types of search engines excellent for finding easy to specify or unusual information, but not nearly as efficient for common information; if you type "AI" into a crawler-based search engine, it will return hundreds of thousands of results.There are several hundred commercial web crawlers; some of popular web crawlers and their abstract descriptions have been introduced in [4] Two of the important issues in web crawler design are Scalability and Extensibility. By scalabl e, we mean that a system must scale up to the entire web, considering its growth. By extensibl e, we mean that it must be designed in a modular way, with the expectation that third parties can add new functionality. Building a scalable crawler is a non-trivial endeavor because the data manipulated by the crawler is too big to fit entirely in memory, so there are p erformance issues relating to how to balance the use of disk and memory. Several techniques have been used to improve the functionality of web crawlers such as: Mining the link structure of web and using it to bring order in URL crawling, automatic classification of web pages and using machine learning methods and domain-specific crawling. [4] Crawling the web in general involves gathering up the links on each visited page and putting them into a queue of links to be followed. Focused crawling (e.g., [5,6,7,8]) reorders the links in the queue as to their predicted likelihood to lead to pages that are relevant to a particular topic. By following high likelihood links first, pages that are relevant to a particular topic are found more quickly. Furthermore, links leading to irrelevant pages tend to fall to the bottom of the queue, and can be ignored once the crawler has determined that the rate of finding new relevant pages from following links has fallen below some given threshold.The key to creating a topic specific search engine is to extract values for specific fields from the web pages, storing the values in a database so that structured queries can be performed over the extracted information. To aid in this endeavor, much research has been done in the area of text classification (e.g., [9,10,11]). Text classification is used in topic specific search engines in at least two areas. First, it is used during crawling toclassify web pages as to whether they are relevant to the given topic. Second, it can be used to classify relevant web pages or content extracted from web pages into a hierarchy. The general idea is to first convert the text to a multidimensional vector representation, where dimensions correspond to words in the text, then to use machine learning or statistical techniques (e.g., decision trees, naive Bayes) to classify the vectors in the multidimensional space.The hypertext structure of the Web provides an additional advantage for web page classification that is not available for classifying text in general: One can use the text in links leading to the page and also the classification of nearby pages to make classification of a particular web page more accurate than if classification were performed on the text of the page alone. In comparison to extracting information from flat text files, it is possible to get increased accuracy when extracting information from web page by taking advantage of the HTML tag structure. One common approach to extracting information from web pages is to write si te specific “wrappers” that extract information based upon regularities of the HTML tag structure that is typically present in a single web site. Another method for extracting information from the Web is to use a bootstrapping approach. In this approach one begins with a small relation and searches the Web for additional tuples to add to the relation. New tuples are added to the relation using a bootstrapping technique, where new tuples are added if they appear on web pages in the same contexts as existing tuples in the relation [12].3 What can focused crawlers do?Focused crawlers can be divided into two categories: those focused on specific topic and those focused on specific document type. If you want to crawl all pages related to “object-oriented fram eworks”, that is the task of topic crawlers [4]. But if you want to fetch all course pages in a university or over the world, then this is the task of focused crawling on document type. This kind of crawler would also crawl on other specific types, such a s resumes, homepages, calls-for-papers, FAQs, movie listings, technical papers, etc. Focused crawling concentrates on the quality of information and the ease of navigation as against the sheer quantity of the content on the Web. A focused crawler [5] seeks, acquires, indexes, and maintains pages on a specific set of topics or document types. Topics are specified to the focusing system using exemplary documents and pages, instead of keywords. Rather than collecting and indexing all accessible Web documents to be able to answer all possible ad-hoc queries, a focused crawler analyzes its crawl boundary to find the links that are likely to be most relevant for the crawl, and avoids irrelevant regions of the Web. In essence, this process will result in personalized sub-webs within the World Wide Web. This method results in significant savings in hardware and network resources, and yet achieves respectable coverage at a rapid rate, simply because there is relatively little to do. Thus, a distributed team of focu sed crawlers, each specializing in one or a few topics, can theoretically manage the entire content of the Web.The ideal focused crawler retrieves the maximal set of relevant pages while simultaneously traversing the minimal number of irrelevant document s on the web. Each focused crawler is far more nimble in detecting changes to pages within its focus than a crawler that crawls the entire Web. Focused crawlers therefore offer a potentialsolution to the currency problem by allowing for standard exhaust ive crawls to be supplemented by focused crawls for categories where content changes quickly.Here is what we found when we used focused crawling for many varied topics at different levels of specificity.??Focused crawling acquires relevant pages steadily while standard crawling (like the ones used in first-generation search engines) quickly loses its way, eventhough they start from the same root set.??Focused crawling is robust against large perturbations in the starting set of URLs. It discovers largely overlapping sets of resources in spite of theseperturbations.??It can discover valuable resources that are dozens of links away from the start set, and at the same time carefully prune the millions of pages that may lie within this same radius. The result is a very effective solution for building high-quality collections of Web documents on specific topics, using modest desktophardware.??Focused crawlers impose sufficient topical structure on the Web. As a result, apart from the naïve topical search, powe rful semi-structured query, analysis,and discovery are also enabled.??Getting isolated pages, rather than comprehensive sites, is a common problem with Web search. With focused crawlers, you can order sites according to thedensity of relevant pages found there. For example, you can find the top fivesites specializing in Computer science research activities.?? A focused crawler also detects cases of competition. For instance, it will take into account that the homepage of a particular auto-manufacturing company likeHonda is unlikely to contain a link to the homepage of its competitor, say,Toyota.??Focused crawlers also identify regions of the Web that grow or change dramatically as against those that are relatively stable.The ability of focused crawlers to focus on a topical sub-graph of the Web and to browse communities within that sub-graph will lead to significantly improved Web resource discovery [5,13]4 What is Active Logic?Active Logic is a kind of “step logic,” which was developed in [2] as formal mechanism for modeling the ongoing process of reasoning. Unlike traditional logical formalisms, a step-logic does not calculate a final set of conclusions which can be drawn from an initial set of facts, but rather monitors the ever-changing set of conclusions as time goes on. There are special persistence rules so that every theorem a present at time t implies itself at time t+1; likewise there are special rules so that if the knowledge base contains both a theorem a and its negation –a, these theorems and their consequences are “distrusted” so they are neither carried forward themselves nor used in further inference. An active logic, then, consists of a formal language (typically first-order) and inference rules, such that the application of a rule depends not only on what formulas have (or have not) been proven so far (this is also true of static logics) but also on what formulas are in the “current” belief set. In general the current beliefs are only a subset of all formulas proven so far: each is believed when first proven but some may subsequentlyhave been rejected. Active Logics have the following characteristics: they are situated in time, maintain a history, tolerate contradictions, and allow meta-reasoning to be done.Based on the above definition, active logics are a family of inference engines that incorporate a history of their own reasoning as they run. Thus at any time t, an active logic has a record of its reasoning at all times prior to t, and it also knows that the current time is t. As it continues to reason from time t, that reasoning is also recorded in the history, marked at time t+1 as having occurred at time t. Thus an active logic records the passage of time in discrete steps, and the “current” time slides forward as the system runs. It is convenient to regard its current inferences as occurring in a working memory, that is then transferred to the history (or long-term memory) in the next time-step. Thus, an active logic has time-sensitive inference rules and consequently time-sensitive inferences. In active logics the current time is itself noted in the working memory—Now (t)—and this changes to Now (t+1) one step later. (A time-step should be thought of as very fast, perhaps 0.1 sec in correspondence with performance of elementary cognitive tasks by hum ans). Thus active logics "ground" Now in terms of real time-passage during reasoning.These characteristics make active logics suitable for use in various domains including time situated planning and execution [15]; reasoning about other agents [16]; reasoning about dialog [17,18], including updating and using discourse context [19]; and autonomous agency [20].4.1 Rules of Active LogicThere are many examples of active logics in various papers. We present here a couple of simple rules.1) Time step update rule: t: Now(t), then : t+1: Now(t+1)is a rule that says: if at the current step, Now has the value t, then, at the next step, let Now have the value (t + 1). This enables the active logic to keep track of step numbers and therefore of time. This is a basic rule and is included in all active logics.2) Another example is the contradiction rule:t: P, not(P), then: t+1: contra(P, not(P))If at a step, we have both P and not(P) present in the database, at the next step, we add contra(P, not (P)) to the database to indicate the contradiction. There will be other rules that will cause the consequences of P and not(P) not to be derived in later steps, and rules that will attempt to resolve the contradiction and reinstate either P or not(P) to the database at a later time.3) We can also have modus ponens: t: P, P ?Q, then conclude: t+1: Q.This says: if at time t, the database contains P and (P ?Q), then in the next time step, conclude Q. Note that if the database contains P, (P ?Q) and (Q ?R), we do not get R immediately, but only after 2 steps. First, we use P and (P ?Q) to obtain Q, then in the second step, we use this together with (Q ?R) to derive R.4) The inheritance rule keeps formulas in the database unless there is a contradiction:t: P , not_know(not(P)), \+ P = Now(t), then conclude: t + 1: P.not_know(P) is true iff P is not in the current database. Since the database is finite, this poses no computational problems. "\+ P = Now(t)" verifies that P is not of the formNow(t) and prevents time from being inherited. This rule also prevents the lemmas of a contradiction from being inherited.5) Let the sentences initially present in the database be: Now (0), Bird (tweety), Bird (x) & not_know (not (fly (x))) ?fly (x). With the above rules of inference, this is what the database looks like at consecutive steps:At step 0: Now(0), Bird(tweety), Bird(x) & not_know(not(fly(x))) ?fly(x)At step 1: Now(1), Bird(tweety), Bird(x) & not_know(not(fly(x))) ? fly(x), fly(tweety) since "not(fly(tweety))" is not present in the database at step 0.The database will not change thereafter.4.2 Why Active Logic for Focused Crawling?The focused crawler [5] has three main components: a classifier which makes relevance judgments on pages crawled to decide on link expansion, a distiller which determines a measure of centrality of crawled pages to determine visit priorities, and a crawler with dynamically re-configurable priority controls which is governed by the classifier and distiller. Detailed description of these components can be found in [4].Two critical factors for the design, implementation and maintenance of a Focused Crawler are: conceptual modeling of the domain, and reasoning support over the conceptual representation. Knowledge representation and reasoning techniques play an important role for both of these factors. By using an Active Logic based framework in Focused Crawler architecture we will be able to create an engine to implement these roles well.A major problem faced by existing crawlers is that it is frequently difficult to learn that some sets of off-topic documents often lead reliably to highly relevant documents. This deficiency causes problems in traversing the hierarchical page layouts that commonly occur on the web. Consider for example a researcher looking for papers on Natural Language processing. A large number of these papers are found on the home pages of researchers at computer science departments at universities. When a crawler finds the home page of a university, a good strategy would be to follow the path to the computer science (CS) department, then to the researchers’ pages, even though the university and CS department pages in general would have low relevancy scores. An adaptive focused crawler based on active logic could in principle learn this strategy by building a tree from query and expanding this tree while the system is in process. It is doubtful that the crawler would ever explore such a path in the first place, especially as the length of the path to be traversed increases.To address this problem, Rennie and McCallum [6] used reinforcement learning to train a crawler on specified example web sites containing target documents. The web site or server on which the document appears is repeatedly crawled to learn how to construct optimized paths to the target documents. However, this approach places a burden on the user to specify representative web sites. Initialization can be slow since the search could result in the crawling of a substantial fraction of the host web site. Furthermore, this approach could face difficulty when a hierarchy is distributed across a number of sites.An additional difficulty faced by existing crawlers is that links on the web are unidirectional, which effectively restricts searching to top-down traversal, a process that we call “forward crawling” (Obtaining pages that link to a particular document is referred to as “backward crawling”). Since web sites frequently have large componentsthat are organized as trees, entering a web site at a leaf can result in a serious barrier to finding closely related pages. For example, when a researcher’s home page is entered, say via a link from a list of papers at a conference site, a good strategy would be for the crawler to find the department member list, and then search the pages of other researchers in the department. However, unless an explicit link exists from the researcher’s page to the CS department member list, existing focused crawlers cannot move up the hierarchy to the CS department home page.ALII utilizes a compact context representation and construct a hierarchy model of query and web pages. The crawler based on active logic also utilizes the limited backward crawling possible using general search engine indices to efficiently focus crawl the web. Unlike Rennie and McCallum’s approach [6], this approach does not learn the context within which target documents are located from a small set of web sites, but in principle can back crawl a significant fraction of the whole web starting at each seed or on-topic document. Furthermore, the approach is more efficient in initialization, since the tree is constructed by directly branching out from the good set of documents to model the parents, siblings and c hildren of the seed set.This focused crawler uses the limited capability of search engines like AltaVista or Google to allow users to query for pages on HTML format linking to a specified document. This data can be used to construct a representation of pages as a tree that occur within a certain link distance (defined as the minimum number of link traversals necessary to move from one page to another) of the target documents regarding to query tree, which improved during the process. This representation is used to train a set of classifiers, which are optimized to detect and assign documents to different categories based on the expected link distance from the document to the target document. Duringthe crawling stage the classifiers are used to predict how many steps away from a target document the current retrieved document is likely to be. This information is then used to optimize the query and search.There are three distinct stages to using the active logic when performing a focused Crawl session:1. An initialization phase when a query present to a search engine. In this phasethe initial tree will be constructed.2. A crawling phase that extract the pages from web sites. In this stage theassociated tree are constructed for each of the seed pages.3. A process phase that evaluate each page tree with query tree. In this phase querytree will improved from time (t) to time (t+1).ALII outputs from the process phase can be used as knowledge input to a Classifier component. ALII as presented, is a representation environment and logical reasoning tool with a formal foundation in Active Logic. The ALII Project aims at developing methods and tools for a Model-based, Semantic Integrating of information sources on Web pages. Current work on the project is centered on a demonstrator application for information services. ALII can search (through the links), acquire, index and maintain pages that are relevant to a predefined set of topics and effectively build high quality collections of Web documents.5 ConclusionsIn this paper we introduce a brief picture of different issues and problems in information integration that can be tackled by using active logic. We have made some detailed suggestions regarding an important application area for active logic: focused web crawling. We believe that such a reasoning component is required for information integration to achieve an intelligent mechanism with the ability to behave effectively over considerably longer time period and range of circumstances.ALII, Active Logic based framework for Information Integration, will utilize a compact context representation and construct a hierarchy model of query and web pages. The crawler based on ALII also utilize the limited backward crawling possible using general search engine indices the efficiency focus-crawl the web.ALII consists of an inference engine with inference rules which: are situated in time, can maintain the history, tolerate contradictions and do meta reasoning. Information Integration system based on ALII can seek (through the links), acquire, index, and maintain pages that are relevant to a user query.References[1] Soumen Chakrabarti, Martin H. van den Berg, Byron E. Dom, Distributed Hypertext Resource Discovery Through Examples, Proceedings of the 25th VLDB Conference, Edinburgh, Scotland, 1999.[2] J. Elgot-Drapkin. Step-logic: Reasoning Situated in Time. Ph.D. Thesis, Department of Computer Science, University of Maryland, College Park, 1988.[3] J. Elgot-Drapkin, S. Kraus, M. Miller, M. Nirkhe and D. Perlis; A Unified Formal Approach to Episodic Reasoning. Technical report, University of Maryland, 1988.[4] A. A. Barfourosh, H. R. Motahary Nezhad, M. O’Donovan-Anderson, D. Perlis. Information Integration in World Wide Web and Active Logic: A survey and problem definition Technical Report, Computer Science Department, University of Maryland, 2001.[5] S. Chakrabarti, M. van den Berg, and B. Dom. Focused crawling: a new approach to topic-specific web resource discovery. Proc. of the 8th International Worldwide Web Conference (WWW8), 1999.[6] J. Rennie and A. McCallum, “Using reinforcement learning to spider the web efficiently,” in Proc. Inter-national Conference on Machine Learning (ICML),1999.[7] Michelangelo Diligenti, Frans Coetzee, Steve Lawrence, C. Lee Giles, Marco Gori. Focused Crawling using Context Graph s, 26t h International Conference on Very Large Databases, VLDB 2000, Cairo, Egypt, pp. 527–534, 2000.。