The impact of handover protocols on the performance of ABR flow-control algorithms in a wir
LTE综述(英文版)
UTRAN LONG TERM EVOLUTION IN 3GPPAntti Toskala Harri Holma Kari Pajukoski Esa Tiirola Nokia Networks Nokia Networks Nokia Networks Nokia Networks P.O. Box 301 P.O. Box 301 P.O.Box 319 P.O.Box 31900045 NOKIA GROUPFinland 00045 NOKIA GROUPFinland90651 OULUFINLAND90651 OULUFINLANDA BSTRACTThe 3rd Generation Partner Ship Project (3GPP) produced the first version of WCDMA standard in the end of 1999, which is the basis of the Universal Mobile Telephone System (UMTS) deployed in the field today. This release, called release 99, contained all the basic elements to meet the requirements for IMT-2000 technologies. Release 5 introduced the High Speed Downlink Packet Access (HSDPA) in 2002, enabling now more realistic 2 Mbps and even beyond with data rates up to 14 Mbps. Further Release 6 followed with High Speed Uplink Packet Access (HSUPA) in end of 2004, with market introduction expected in 2007. Alongside with on-going further WCDMA development, work on Evolved Universal Terrestrial Radio Access (UTRA) has been initiated in 3GPP. The objective of Evolved UTRA is to develop a framework for the evolution of the 3GPP radio-access technology towards wider bandwidth, lower latency and packet-optimized radio-access technology with peak data rate capability up to 100 Mbps. This paper introduces the requirements, the current state of progress in 3GPP, findings on the performance, agreed architecture as well as expected schedule for actual specification availability.1.INTRODUCTIONFollowing the first wave of WCDMA based networks rollout with data rates up to 384 kbps both in the uplink and downlink [1], now the High Speed Downlink Packet Access (HSDPA) is being rolled out with 2-3 Mbps practical data rate capabilities and theoretical peak rate of 10 Mbps or even more and with High Speed Uplink Packet (HSUPA) set to follow during 2007 with capability up to 5.7 Mbps in the uplink as well [2].In order to prepare for future needs, 3GPP has initiated activity on the long term evolution of UTRAN (Universal Terrestrial Radio Access Network), which is aiming clearly beyond to what the WCDMA can do with HSDPA or HSUPA in case of uplink. The UTRAN long-term evolution work is looking for the market introduction of Evolved UTRAN (EUTRAN) around 2010, with resulting specification availability planned toward end of 2007. The feasibility study is currently on going and key decisions on the multiple access as well as on the protocol architecture have been recently reached. Feasibility study finalization is expected for September 2006 time frame, after which actual specification development would start. This paper covers in section 2 the requirements for the work defined in 3GPP, and then looks at the network and protocol architecture developments in section 3. Section 4 covers the physical layer technology selection. Section 5 addressed the feasibility study findings on the performance and remaining work and expected schedule is covered in section 6. Conclusions are drawn in section 7.2.REQUIREMENTSFor the long term evolution, clearly more ambitious goals were necessary to make it worth the effort compared with what can be achieved with current system. Thus the following targets were defined [3]:•User plane latency below 5 ms with 5 MHz or higher spectrum allocation. With spectrum allocationbelow, latency below 10 ms should be facilitated.•Reduced control plane latency•Scalable bandwidth up to 20 MHz, with smaller bandwidths covering 1.25 MHz, 2.5 MHz, 5 MHz,10 MHz and 15 MHz for narrow allocations. Also1.6 MHz is considered for specific cases.•Downlink peak data rates up to 100 Mbps•Uplink peak data rates up to 50 Mbps• 2 to 3 times capacity over the existing Release 6 reference scenarios with HSUPA• 2 to 4 times capacity over the existing Release 6 reference scenarios with HSDPA•Improved end user data rates at the cell edge•Support for packet switched (PS) domain onlyWhile big investments have been done and are being done in WCDMA and GSM based networks, also inter-working with WCDMA and GSM is a key requirement for a new system part of the 3GPP technology family. The requirement for handover between legacy systems and E-UTRAN is for services with real time quality a break of 300 ms and for the non-real time services 500 ms would be sufficient.Further there is a desire to have reduced operating cost (often referred as OPEX) and reduced network investment costs (often referred as CAPEX).The agreed baseline assumptions also include 2 receiver antennas in the mobile terminal, which facilitates usage of advanced antenna technologies, such as Multiple Input Multiple Output (MIMO) antenna concepts. Respectively, a typical base station is expected to have two antennas transmit and receive capabilities.The defined mobility support are aiming for optimized performance for mobile speed of less than 15km/h, and high performance for speeds up to 120km/h, and the connection should be maintained with mobile speeds even up to 350 km/h.1-4244-0330-8/06/$20.00 2006 IEEEWORK ARCHITECTUREThe long-term evolution network architecture is characterised by three special requirements:•Support for PS domain only i.e. there will not be connection to circuit switched (CS) domain nodes,such as the Mobile Switching Centre, but speechservices need to be handled as Voice over IP (VoIP)calls.•Tight delay targets for small roundtrip delay. The roundtrip delay target is 5 ms for bandwidths of 5MHz or more. Respective target is 10 ms for thebandwidths of below 5 MHz.•Reduced cost of the systemThe architecture proposals made for the study could be characterized under two categories:•BTS based approach, which adds more functionality for the base station and having all radio relatedfunctionalities in the BTS•Two node architecture for radio protocols with radio related signalling etc. terminating in the node abovebase station.Following the intensive discussion, it was agreed to use two node architecture, with the functionality divided between two network elements, eNode B and access gateway (aGW). Itwas then agreed that radio related signalling (RRC) as well as all layers of retransmission are located in eNode B. MAC layer functionality etc, similar to HSDPA/HSUPA operation, will remain in the eNode B as well. Ciphering and header compressions were decided to be located in aGW, as shown in Fig. 1. The interface connecting aGW and eNode B (BTS) is called S1 interface and that will have some similarity with the Iu interface between the current radio access network and core network, though the functional split is slightly different due to the ciphering and header compression in core network (aGW) side. Further interface called X2 will be defined between eNode Bs for e.g. handover purposes.One of the key issues impacting the architecture was the potential need and type of macro diversity combining to be supported for EUTRAN. As with was decided that there no need for macro-diversity, similar combining functionality as with WCDMA in Radio Network Controller (RNC) [2] was not needed.server for future study.IV.MULTIPLE ACCESS TECHNOLOGY Following the requirements laid down for the multiple access technologies, it has become evident that something else than the use of the current radio interface technology needs to be considered for the radio access supporting up to 100 Mbps and up to 20 MHz bandwidth. While the WCDMA radio interface technology, as described in details in [1], is very efficient for proving (downlink peak) data rates up to 10 Mbps, the requirements such as reaching 100 Mbps peak rate rates cannot be met with WCDMA technology with reasonable mobile terminal complexity. As an example in the downlink direction this would require either multiple 5 MHz carriers or higher chip rate, neither of the solutions very attractive when aiming for very high performance with advanced receivers in the mobile terminal.As this was clearly understood in 3GPP community, the decision was made to adopt the for the uplink direction the Single Carrier FDMA (SC-FDMA) due to the good performance in general and superior properties in terms of uplink signal Peak-to-Average Ratio (PAR) when compared to OFDM in the uplink. In the downlink direction the solution was OFDM, mainly due to the simplicity of the terminal receiver in case of large bandwidths in difficult environment. Also for the network side transmission PAR was not considered such a key problem.The following sub-sections on multiple access details focus on operation with the paired frequency bands (by using frequency division duplex, FDD), though work in 3GPP covers also time division duplex (TDD).A. DownlinkFor downlink, the adoption of OFDMA enabled flexiblesupport of different bandwidth options. The basic OFDMchain is illustrated in Fig. 2 as used for the feasibility studiesat least, though obviously several advanced techniques arebeing considered on top of the basic OFDMA operation.These technologies include frequency domain scheduling,MIMO antenna technologies and variable coding andOne of the key aspects for the air interface is a scalablesolution to support the large number of different bandwidths,starting from 1.25 MHz and all the way to 20 MHz. Thesingle set of parameters for sub-carrier spacing etc. providesupport for different bandwidths by only changing the numberof sub-carriers while keeping the frame length as well assymbol length constant. The parameters defined during thefeasibility study can be found from [6].B. UplinkThe chosen SC-FDMA solutions are based on the use ofcyclic prefix to allow for high performance and lowcomplexity receiver implementation in the base station. Thereare two different variants of SC-FDMA under discussion,which differ from each other only from the spectrum use. Theso called blocked or localized FDMA uses a continuesfrequency band for a single users while with the InterleavedFDMA (IFDMA) the frequency band is used in non-continuous way, as described for example in [3], but only stilltransmitting one modulation symbol in time domain; thusretaining the advantage of low PAR (sometimes referred as crest factor) when compared to OFDMA. With FDMA the type of modulation applied will impact the PAR, but with OFDMA the large number of parallel sub-carriersFigure 3: FDMA and IFDMA principles for frequencydomain generation of signals.make the resulting PAR 2-6 dB higher than FDMA. 3GPP did decide in December 2005 to use FDMA for PAR reasons. The conceptual transmission methods of localized FDMA and IFDMA are illustrated in Fig. 3. OFDM is well know from e.g. the IEEE 802.11 standardsfamily, while FDMA variants with cyclic prefix representnewer proposals for wireless mobile communicationstandards, though it has been published for almost a decadeago, for example in [4].For the uplink considerations the cell edge operation ishighlighted due operator requirements. A mobile data servicethat provides a high data rates in the majority of the cell areais easier to market and sell compared to a mobile data servicethat severely limits the high data rate availability to a smallfraction of the cell area. Hence even a few dBs improvementin PAR is very essential to achieve high data rate availabilityclose to cell edge.The general FDMA transmitter and receiver concept (notdirectly usable for IFDMA) is illustrated in Fig. 4. With thegeneration of IFDMA the block repetition after modulatorshould added or other alternative is the use of FFT/IFFT inthe transmitter as well. Those could be applied to produce theFDMA signal as well, as seen in the example in Fig. 3 withboth IFDMA and FDMA principles illustrated. In case ofIFDMA multiple users can then share the frequency domainresource by using different offset for starting their sub-carrieroccupancy. IFDMA is more sensitive to imperfections likefrequency offset as there are now more borders between usersin frequency domain.In 3GPP discussions an important learning was also that oneshould use instead of PAR, so called Cubic Metric [5] insteadfor describing the impact for the power amplifiers due tosignal envelope variations. The use of CM takes better thepractical amplifier properties into account compared to PAR.The OFDMA and SC-FDMA uplink CM comparison isshown in Fig. 5, indicating the difference depending on themodulation being used. With optimised modulation thedifference may be up to 4 dB in the favour of SC-FDMA.FDMAIFDMATransmitterdomain signal generation.C. Physical layer parameter selectionThe work is on-going to identify the base parameters, such as the transmission time interval (TTI) to be used. For the feasibility study a common parameter set has been agreed, with the example shown in Table 1 for 5 and 10 MHz bandwidths. The common nominator for all bandwidths is theshort TTI of 0.5 ms; this was chosen to enable a very short latency with L1 Hybrid ARQ as already introduced with HSDPA and HSUPA [2].Table 1: Downlink Parameters for 5 and 10 MHz bandwidths. Bandwidth 5 MHz 10 MHz Frame size 0.5 ms Sub-carrier Spacing 15 kHz FFT size 512 1024 Occupied Sub-carriers 301 601 Sampling rate 7.68 MHz 15.36 MHzChannel coding for EUTRAN is attracting optimisation proposals to use different forward error correction than Turbo coding. One reason for discussion with channel coding is the increasing complexity of iterative Turbo decoding with high data rates combined with low latency L1 H-ARQ.Other key parameters have relationship with the multiple access method, such as the sub-carrier spacing of OFDM. The selection is a compromise between support of high Doppler frequency, overhead from cyclic prefix, implementation imperfections etc. The sub-carrier spacing used in feasibility study is 15 kHz. To optimize for different delay spread environments (e.g. ranging from urban pico cells to rural mountain area cells), two cyclic prefix values are to be used. Doppler will also impact the parameterisation, as the physical layer parameterisation needs to allow maintaining the connection at 350 km/h. It has been recognised, however, that scenarios above 250 km/h are specific cases, such as the high-speed train environment. The optimisation target is clearly the lowerCM vs rolloff with different modulationsrolloffC M [d B ]Figure 5: SC-FDMA CM compared to OFDM uplink CM.mobile terminal speeds, below 15 km/h, and performance degradation is allowed for higher speeds.This focus on optimisation for low speeds and urban small cells is visible also in the agreed evaluation scenarios. As part of the physical layer technology selection, the first evaluation scenarios to be considered will be the 3 km/h and 30 km/h scenarios, 2 GHz carrier frequency and 10 MHz bandwidth. The second evaluation scenario is 900 MHz carrier frequency with 1.25 MHz bandwidth. The distance between cell sites is from 500 m to 1732 m.V. PERFORMANCE The interesting question when designing a new system is obviously what is the potential for performance improvement over the existing systems. When looking at the HSPDA performance in [2] is can be seen that especially in the macro-cell environment (and 5 MHz bandwidth) HSDPA is setting rather high bar of the baseline reference performance that is not easily beaten with a classical OFDM approach, as has been discussed in 3GPP previously as well. When one starts to look for higher bandwidths and also environments where multiple antenna solutions could be applied together with advanced methods like frequency domain scheduling, there are opportunities to have better performance level, but not necessary with that high margin as originally aimed (3 to 4 times over the reference). The simulations show 2.5 times over HSDPA Release 6 with 2-antenna Rake receiver in Fig. 6. The spectral efficiency improvements in LTE over HSPA are mainly due to• OFDM with frequency domain equalizationproviding user orthogonality. HSDPA can utilize equalizers to improve the orthogonality in multipath channel, but practical equalizers are not able to remove all intra-cell interference.0.00.20.40.60.81.01.21.41.61.8HSPA Release 6LTEb p s /H z /c e l lFigure 6: Downlink spectral efficiency [6]. • Frequency domain packet scheduling. OFDM allows transmitting using the sub-carrier that has better propagation and interference conditions.• Inter-cell interference rejection combining or interference cancellation can be implemented both in HSDPA and in OFDM, but the potential gains areexpected higher in OFDM with lower complexity due to narrowband carriers. In the uplink direction the use of SC-FDMA offers possibility especially for the cell edge performance as one can create orthogonal uplink which helps the link budget for the users at cell edge. An example reference case is shown in Fig. 7, which shows the uplink performance when compared to the reference HSUPA reference case from 3GPP. With the 1732 meters cell site distance, macro cell layout and 20 dB indoor penetration loss used, the uplink data rate at cell edge remains rather small, and the benefit of the orthogonal uplink with SC-FDMA is fully visible [7]. The results both for the uplink and downlink are for the packet data with full buffer and proportional fair scheduler in the BTS. For the terminal two receiver antennas are assumed while for BTS both twotransmit and receive antennas were used. For shadowing 8 dB standard deviation was assumed and realistic channelestimation was included in the simulation based on the pilot symbols in the data stream.More results can be found in the latest versions of [8] following the finalization of the evaluation of the selected methods against the HSUPA/HSDPA reference cases.VI. 3GPP SCHEDULE Following the creation of the work item for actual specification work, 3GPP has defined the target date for the detailed (stage 3 in 3GPP terms) specification availability by September 2007. The stage 2 (not yet implementation details)level specification is targeted to be approved in March 2007. The expected specification release is Release 8, but that is to be confirmed later asFigure 7: Performance of SC-FDMA vs. WCDMA.3GPP does only decide the actual release once the work iscompleted. Performance requirements are expected to becompleted by December 2007.VII. CONCLUSIONS In 3GPP UTRAN Long Term Evolution work is on going todefine an evolved UTRA/UTRAN system with peak data rate capabilities of up 100 Mbps for downlink and up to 50 Mbps for uplink. Combining this with the 3GPP experience from mobility management ensures the support of seamlessmobility and service offering. The work on-going in 3GPP is not as such replacing WCDMA evolution, but is introducing besides new architecture also new radio access technology. 3GPP has decided to use OFDM in downlink and SC-FDMA in the uplink. In the network architecture flat two node architecture has been chosen. The BTS is handling now all radio related functionality previously divided between BTS and RNC, only PDCP and ciphering are located in the Access Gateway (aGW). R EFERENCES[1] 3GPP technical Report, TR 25.913 version 2.1.0 `` Requirements for Evolved UTRA and UTRAN '', 3GPP TSG RAN#28, Quebec, Canada,June 1-3, 2005, Tdoc RP-050384. [2] Holma, H. and Toskala, A., ``WCDMA for UMTS'', 3rd edition , Wiley,2004. [3] Sorger, U., De Brock, I. and Schnell, M., “Interleaved FDMA –A NewSpread Spectrum Multiple Access Scheme ”, IEEE Globecomm 1998. [4] Czylwik, A., `` Comparison between adaptive OFDM and single carriermodulation with frequency domain equalisation '', IEEE VehicularTechnology Conference 1997, VTC-97, Phoenix, pp. 863-869. [5] Holma H. and Toskala A., “HSDPA/HSUPA for UMTS, Wiley, 2006 [6] Nokia, “LTE Evaluation Results”, May 2006, Shanghai, China, TSGRAN WG1#45, May 8-12, 3GPP Tdoc R1-061238. [7] Nokia, “System Level Evaluation of the Concepts” November 2005,Seoul Korea, TSG RAN WG1#43bis, 3GPP Tdoc R1-051411.[8] 3GPP technical Report, TR25.814 v1.2.1 Physical Layer Aspects for Evolved UTRA '', 3GPP TSG RAN#31, Hainan, China, March 8-10,2006, 3GPP Tdoc RP-060201.。
卫星网络移动性管理协议S-MIPv6
卫星网络移动性管理协议S-MIPv6窦志斌【期刊名称】《无线电工程》【年(卷),期】2015(045)010【摘要】天基网络要求卫星具有跨波束、跨卫星的移动性管理功能, 而传统地面网络中的移动性管理协议MIPv4和MIPv6都无法同时支持单节点和子网的移动性. 针对以上问题提出了一种基于IPv6的同时支持单节点和移动子网的移动性管理协议—S-MIPv6, 该协议充分吸收了MIPv6、 NEMO和PMIPv6协议的优点, 采用基于网络的移动性管理架构, 并根据卫星空间组网的特点优化了信令流程, 降低了链路通信开销. 同时对S-MIPv6协议的入网、域内和域间切换开销给出了理论分析, 为后续S-MIPv6协议的实现和完善奠定了基础.%In the space-based network,the satellites are required to have the capability of inter-beam and inter-satellite mobility management functions, and in the traditional ground-based network, the mobility management protocols ( i. e. MIPv4, MIPv6 ) are incapable to support simultaneously the mobility of nodes and networks.Based on this problem,this paper puts forward an IPv6-based mobility management protocol(S-MIPv6).S-MIPv6 adopts the design principles of MIPv6,NEMO and PMIPv6,and optimizes the signa-ling flow based on satellite networking characteristics for radio-link communication overhead reduction. The theoretical analysis is performed for the overhead of three core S-MIPv6 procedures:initial network access,intra-domainhandover and inter-domain handover, which provides the guideline for the implementation and improvement of S-MIPv6.【总页数】5页(P11-15)【作者】窦志斌【作者单位】中国电子科技集团公司第五十四研究所, 河北石家庄050081【正文语种】中文【中图分类】TP393.11【相关文献】1.面向动态外地代理的卫星网络移动性管理机制 [J], 董彦磊;李东昂;刘勤;汪春霆;史可懿2.面向低轨卫星网络的动态虚拟化分布式移动性管理方法研究 [J], 朱洪涛;郭庆3.面向低轨卫星网络的动态虚拟化分布式移动性管理方法研究 [J], 朱洪涛;郭庆4.大规模低轨卫星网络移动性管理方案 [J], 吴琦;郭孟泽;朱立东5.面向航空节点的IP/LEO卫星网络移动性管理方法(英文) [J], 郭欣;张军;张涛;丁演文因版权原因，仅展示原文概要，查看原文内容请购买。
ho问题回答
HO1. IntroductionHO, short for Handover, is a fundamental concept in wireless communication systems. It refers to the process of transferring an ongoing call or data session from one cell to another without interrupting the communication. Handovers are crucial in maintaining seamless connectivity and ensuring smooth user experience in mobile networks.In this article, we will explore the significance of handovers, understand the various types of handovers used in different scenarios, and delve into the technical aspects of handover procedures.2. Significance of HandoversHandovers play a vital role in mobile communication systems for several reasons:2.1 Seamless ConnectivityOne of the primary objectives of handovers is to ensure uninterrupted connectivity for mobile users. As users move from one cell to another while making calls or using data services, it is essential to transfer their ongoing sessions seamlessly without any disruptions. Handovers enable this smooth transition between cells, allowing users to maintain their connections without experiencing call drops or data loss.2.2 Load BalancingHandovers also facilitate load balancing in cellular networks. By intelligently distributing users across multiple cells, handover mechanisms help optimize network resources and prevent congestion in specific cells. This dynamic load management ensures efficientutilization of network capacity and enhances overall network performance.2.3 Quality of Service (QoS)Handovers contribute significantly to maintaining QoS parameters such as call quality and data throughput. When a user moves towards the edge of a cell’s coverage area, signal strength may weaken, leading to degradedservice quality. By triggering a handover to a neighboring cell with better signal strength, QoS can be maintained at an acceptable level.3. Types of HandoversThere are several types of handovers used in different scenarios based on network architectures and mobility patterns:3.1 Intra-Cell HandoverIntra-cell handover, also known as soft handover, occurs when a mobile device moves within the coverage area of a single base station. In this case, the handover process involves transferring the connection between different sectors or antennas within the same cell. Intra-cell handovers are typically transparent to users and ensure seamless connectivity without noticeable disruptions.3.2 Inter-Cell HandoverInter-cell handover, also referred to as hard handover, takes place when a mobile device moves from one cell to another within the same network. This type of handover involves transferring the ongoing session from the serving cell to a target cell. Inter-cell handovers require coordination between multiple base stations and involve more complex procedures compared to intra-cell handovers.3.3 Inter-System HandoverInter-system handover occurs when a mobile device moves betweendifferent wireless technologies or networks, such as from GSM (2G) to UMTS (3G) or from LTE (4G) to Wi-Fi. These handovers involve not only changing cells but also transitioning between different network architectures and protocols.3.4 Vertical HandoverVertical handovers are specific types of inter-system handovers that involve switching between heterogeneous networks with varying characteristics. For example, a vertical handover may occur when a user transitions from cellular network coverage to Wi-Fi connectivity or vice versa. These handovers aim to provide seamless connectivity while considering factors such as signal strength, network availability, and user preferences.4. Handover ProceduresHandovers involve several steps and procedures that ensure successful transfer of ongoing sessions:4.1 Measurement and TriggeringThe first step in a handover procedure is measuring the signal quality and strength of neighboring cells or systems. The serving cell continuously monitors these measurements and triggers a handover decision when certain predefined thresholds are met.4.2 Handover DecisionOnce triggered, the handover decision is made based on various factors such as signal strength, interference levels, network load, and QoS requirements. The decision-making process aims to select the most suitable target cell or system for handover.4.3 Handover PreparationAfter the handover decision, the serving cell initiates preparations for the handover. This involves allocating resources in the target cell and coordinating with neighboring base stations or systems.4.4 Handover ExecutionDuring the handover execution phase, the mobile device switches its connection from the serving cell to the target cell. The switch should be seamless and imperceptible to users, ensuring uninterrupted communication.4.5 Handover CompletionOnce the handover is executed successfully, a confirmation message is exchanged between base stations or systems to finalize the handover process. This ensures that both ends of the communication are aware of the transition and can resume normal operation.5. ConclusionHO (Handover) is an essential mechanism in wireless communication systems that enables seamless connectivity, load balancing, and maintenance of quality of service parameters. By understanding different types of handovers and their procedures, network operators can optimizetheir networks for efficient resource utilization and improved user experience.Handovers continue to evolve with advancements in technology, such as 5G networks and network slicing. These developments aim to further enhance handover capabilities and provide even better connectivity in future wireless communication systems.Remember: HO is not just a simple abbreviation; it represents a critical aspect of mobile networks that keeps us connected wherever we go!。
工程方案英文
工程方案英文Project Title: Design and Implementation of a Solar-Powered Water Pumping System for a Rural Community in [Country Name]Project Background:Access to clean and reliable sources of water is essential for the well-being of any community. However, many rural areas in [Country Name] still face significant challenges in obtaining a sustainable water supply. In these areas, the absence of a dependable electrical grid makes it difficult to provide consistent water pumping services. As a result, many communities rely on manual pumping systems or costly diesel-powered pumps, which are not only inefficient but also have a negative impact on the environment.To address this issue, our team proposes the design and implementation of a solar-powered water pumping system for a rural community in [Country Name]. This project aims to provide a sustainable and reliable water supply, reduce dependency on non-renewable energy sources, and improve the quality of life for the residents in the target community.Project Objectives:The primary objective of this project is to design, install, and test a solar-powered water pumping system that meets the water needs of the target community. The specific objectives include:1. Conduct a comprehensive site assessment to determine the water demand, geophysical conditions, and solar resource potential of the target area.2. Design a solar-powered water pumping system that is tailored to the specific needs of the community, taking into account factors such as water demand, elevation, and seasonal variations in sunlight.3. Procure and install the necessary equipment, including solar panels, pumps, storage tanks, and distribution systems, in collaboration with local suppliers and contractors.4. Train local community members on the operation and maintenance of the water pumping system to ensure its long-term sustainability.5. Monitor and evaluate the performance of the system, making any necessary adjustments to optimize its efficiency and effectiveness.Project Approach:The design and implementation of the solar-powered water pumping system will involve the following key activities:1. Site Assessment:- Conduct a detailed survey of the target community to assess the water demand, existing water sources, and topographical features.- Install meteorological equipment to measure solar radiation levels and climatic conditions that may impact the performance of the solar-powered system.2. System Design:- Use the data collected from the site assessment to determine the appropriate size and configuration of the solar panels, pumps, and storage tanks needed to meet the water demand of the community.- Integrate the design with a backup power system, such as a battery or generator, to ensure continuous water supply during periods of low sunlight.3. Equipment Procurement and Installation:- Source high-quality solar panels, pumps, and storage tanks from reputable suppliers, considering factors such as reliability, efficiency, and cost-effectiveness.- Collaborate with local contractors and technicians to install the solar panels, pumps, and storage tanks according to the design specifications, ensuring compliance with safety and quality standards.4. Community Engagement and Training:- Work closely with community leaders and stakeholders to build awareness and support for the project, fostering a sense of ownership and responsibility among the residents.- Provide practical training for community members on the operation, maintenance, and troubleshooting of the solar-powered water pumping system, empowering them to take an active role in its long-term management.5. Monitoring and Evaluation:- Implement a monitoring plan to regularly assess the performance of the water pumping system, capturing data on water production, energy consumption, and system uptime.- Use the data collected to identify any issues or inefficiencies and make informed decisions about system optimization and maintenance.Project Deliverables:Upon completion of the project, the following deliverables will be provided:1. Technical report documenting the site assessment, system design, equipment specifications, and installation details.2. Training materials and manuals for the operation and maintenance of the solar-powered water pumping system.3. Monitoring and evaluation reports illustrating the performance and impact of the system on water accessibility and community well-being.4. Handover of the fully operational water pumping system to the community, with a detailed plan for ongoing maintenance and support.Project Budget and Timeline:The proposed budget for the design and implementation of the solar-powered water pumping system is estimated at [INSERT BUDGET AMOUNT] and is expected to cover expenses related to equipment procurement, installation, training, and monitoring. The project timeline is projected to span [INSERT PROJECT DURATION] months, with specific milestones and activities outlined in a detailed work plan.Project Sustainability and Impact:The successful implementation of the solar-powered water pumping system is expected to have a lasting impact on the target community, providing a reliable and sustainable water supply that improves the health, well-being, and livelihoods of its residents. Additionally, the use of renewable energy sources will reduce the community's dependency on non-renewable resources and lower their environmental footprint, contributing to long-term sustainability and resilience.Conclusion:The design and implementation of a solar-powered water pumping system for a rural community in [Country Name] represents a significant opportunity to address the critical need for reliable water access in underserved areas. Through a comprehensive approach that combines community engagement, technical expertise, and sustainable energy solutions, this project has the potential to make a tangible difference in the lives of the people it serves. We are committed to delivering a high-quality, impactful solution that empowers the community and sets a positive example for sustainable development in [Country Name].We look forward to the opportunity to collaborate with stakeholders and secure the necessary support to bring this project to fruition. Thank you for considering our proposal.。
建筑工程施工管理英文文献
建筑工程施工管理英文文献Construction Project Management in the Field of Architecture: An OverviewIntroductionIn the realm of architecture, effective construction project management is crucial for ensuring the successful completion of projects. This article aims to provide an overview of construction project management in the field of architecture, exploring key concepts, methodologies, and best practices.1. Definition and Importance of Construction Project ManagementConstruction project management refers to the planning, coordination, and control of a project from inception to completion. It involves various tasks, such as organizing resources, managing budgets, scheduling timelines, and ensuring quality control. The role of a construction project manager is pivotal in driving the project towards success while simultaneously navigating challenges and mitigating risks.2. Key Components of Construction Project Management2.1 Project InitiationThe project initiation phase involves defining project goals, determining feasibility, and establishing the project scope. During this stage, a project manager identifies key stakeholders, assesses available resources, and prepares a preliminary budget and schedule.2.2 Planning and DesignIn the planning and design phase, the project manager collaborates with architects, engineers, and other experts to develop detailed blueprints, technical drawings, and specifications. This phase also includes obtaining necessary permits and approvals, conducting site surveys, and outlining construction methodologies.2.3 Procurement and Resource ManagementEfficient procurement and resource management are vital aspects of construction project management. This involves sourcing materials, equipment, and labor, while ensuring cost-effectiveness, quality assurance, and adherence to project schedules. Effective communication and negotiation skills are essential in establishing partnerships with suppliers, contractors, and subcontractors.2.4 Construction and ExecutionThe construction and execution phase involves overseeing and coordinating the actual construction process. A project manager must monitor progress, enforce safety protocols, manage change orders, and address any unexpected issues that arise onsite. Regular site inspections, progress reports, and communication with the project team are essential during this stage.2.5 Risk Management and Quality ControlConstruction projects are inherently subject to risks, such as delays, budget overruns, and safety hazards. A skilled project manager implements risk management strategies to identify potential risks, develop contingency plans, and mitigate their impact. Additionally, ensuring quality controlthroughout the construction process is crucial to achieving a satisfactory result.2.6 Project CloseoutThe project closeout phase involves final inspections, ensuring regulatory compliance, and coordinating the handover of the completed project to the client. Documentation of warranties, as-built drawings, and operation manuals are also essential components of closing out a construction project.3. Best Practices in Construction Project Management3.1 Effective CommunicationClear and timely communication is a fundamental factor in successful construction project management. A project manager must establish open lines of communication among all stakeholders, fostering collaboration, addressing concerns, and ensuring that objectives are effectively shared.3.2 Comprehensive Project DocumentationMaintaining accurate and detailed project documentation is crucial throughout the entire construction process. This includes contracts, permits, change orders, progress reports, and meeting minutes. Well-organized documentation facilitates smooth communication, aids in dispute resolution, and forms a valuable resource for future reference.3.3 Regular Monitoring and ReportingRegular monitoring of project progress is essential for identifying issues, tracking milestones, and evaluating the project's overall performance.Timely reporting allows for effective decision-making, enables proactive risk management, and ensures that project goals are being met.3.4 Embracing TechnologyThe use of advanced construction project management software and tools can significantly enhance project efficiency. These tools aid in scheduling, budgeting, collaboration, and data analysis, providing real-time insights and facilitating informed decision-making.ConclusionConstruction project management is a critical aspect of successful architecture projects. Through effective planning, coordination, and control, project managers navigate challenges, ensure timely completion, and deliver high-quality results. By adhering to best practices and utilizing cutting-edge tools, the field of construction project management continues to evolve, contributing to the growth and success of the architectural industry.。
交通专业英语翻译英文部分
ABSTRACTModeling of user traffic and the mobility impact of mobile users onto cellular networks is considered. The quality of service and traffic- handling capacity offered by the network play the most important roles. This article discusses the requirements on a traffic model and on performance design objectives which can be used as a basis for designing and engineering cellular networks. Requirements from actual network operation are discussed and are illustrated by measurement results.Traffic Engineering Experience from Operating Cellular Networkscurrent digital cellular networks are showing rapid growth, and a new generation of cellular networks is already under research . A network operator, situated at the interface between mobile users and equipment suppliers, must develop appropriate strategies:To design the network in the most favorable way, selecting the optimum technical equipmentTo engineer the network efficientlyTo offer a high quality of service to mobile usersSome of these objectives are conflicting and require appropriate compromises. Obviously, a traffic model is required which allows to map user density and mobility onto user and signaling traffic demand at the various defined network interfaces. On the other hand, criteria for quality of service and performance have to be established, which form the guidelines for designing and engineering the network.The international standardization process involves a number of recommendations as well as service quality and performance issues which are referred to in this article. In a perspective is given on the ITU-T (Telecommunication Standardization Sector of the International Telecommunications Union) work in teletraffic engineering. Reference describes the development of standards in the area of personal communications and traffic engineering. A multiplic ity of excellent scientific papers deal with the impact of mobility on the performance of cellular networks. However, a consistent concept, covering the overall engineering and operating aspects of a real network, seems not to be considered. Such a model may include the elements shown in Fig. 1.Two inputs of the model take into account the behavior of the mobile user:A call traffic model, describing the usage of offered services. This model includes, for example, procedures for call handling and operation of supplementary services.A mobility traffic model, describing the occurrence of procedures such as location updating and handoverFurthermore, a network model is required that specifies the reference points for user information and signaling traffic, and provides parameters to be used in an optimization process for the network organization.These inputs allow calculation of the reference loads for individual network elements. Together with appropriate performance parameters, the capacities of the network and the network elements can be evaluated and tested.The elements of the model are discussed in the following sections. A network example is presented in the second section by referring to a well established network standard. In the third section user behavior is discussed based on selected field measurements. In the fourth section reference loads of individual network elements are considered using the mobile user and his/her behavior as the basic engineering unit. Performance objectives are treated in, and finally conclusions are given in the final section.NETWORK MODELfigure 1 shows a standalone configuration of a public land mobile network (PLMN). A GSM (Global System for Mobile Communication)-like network is considered as an example. This network is documented in detail in the appropriate literature (e.g.). The following contains a short description of the network elements and interfaces referred to in the fol- lowing sections.Within a base station subsystem (BSS), base transceiver systems (BTSs) provide radio coverage for mobile stations. Several BTSs may be controlled by a centralized base station controller (BSC). The BSC manages the assignment of radio channels and handover between neighboring BTSs, connected to the same BSC.The mobile switching center (MSC) provides the switching functions for its particular area. In the architecture shown in Fig. 2, the MSC also includes management functions for the handover between BSSs connected to the MSC and between different MSCs.In most existing implementations a visitor location register (VLR) and an equipment identity register (EIR) are implemented together with the MSC in the same physical node. These databases provide location registration and screening functions for mobile subscribers and termina1 equipment within the MSC area.The home location register (HLR) is a database used for storing subscriber service data and provides location registration functions for mobile users within the system area.Signaling System No. 7 (SS#7) provides a packet-switching control network connecting the MSC/VLR/EIR and HLR. It also provides a protocol architecture which includes mobile- specific signaling protocols at the application layer.The gateway functions between a PLMN domain and a fixed peer network domain are realized by gateway MSCs (GMSCs) on the PLMN side and gateway exchanges (X:Ns) on the fixed network side (e.g., ISDN: integrated services digital network).The interfaces between network elements are important, since they define the reference points for signaling and user information traffic. Figure 2 shows as an example interface on the radio path (Um), between BTS and BSC (Abis), between BSC and MSC (A), between network elements connected by the SS#7 network (C,D,E), and between the PLMN and fixed peer network (N).The following geographical areas in a PLMN domain are of importance, refer to Fig. 3:Cell (BTS area): active calls and possibly signaling transactions of mobile users entering a new cell must be handed over.BSC area: includes all cells served by one BSC. Handover procedures performed between neighboring cells, connected to one BSC, are controlled by the BSC.Location area (LA): forms a collective of neighboring cells which is stored as location information of mobile users in the VLR. In the case of mobile terminating call attempts or terminating short messages, the destination mobile user is paged in his/her LA.Paging area (PA): defines the collective of all LAs that include cells of the BSC area. The BSC is in charge of generating copies of paging requests for these LAs and must provide sufficient processor capacity.MSC/VLR area: Idle mobile users entering a new VLR area have to register their new location (VLR) in the HLR. Handover procedures performed between neigh- boring cells of different BSCs are controlled by the MSC(s).Due to the mobility of its users, the geographical organization of a PLMN has a major influence on the signaling traffic.TRAFFIC MODELmobile users are sources and consumers of traffic in M cellular networks. It is natural to define a mobile user as the basic unit for the network engineering process. Mobile users make use of cellular networks in multiple ways, and two models are developed: call traffic and mobility traffic. Both models deal with the average behavior of a user, which can be derived from traffic measurements, for example.CALL TRAFFIC MODELThe call traffic model describes the user and signaling impact due to the usage of offered services. It includes procedures like establishment of mobile originating and mobile terminating calls, transmission and reception of short mes- sages, and operation of supplementary services.Measurements show that this part of the traffic is geographically homogeneous. Typical rates of mobile originating call (MOC) and mobile terminating call (MTC) attempts (Fig. 4a) and the mean holding time (Fig. 4b) are shown for various location areas in Germany during the busy hour. The reference interface is the radio interface UmFrom measurements a typical mean ratio of 213 MOCs and 113 MTCs at the radio interface can be verified.The position of the busy hour of user traffic depends on several factors (user type, tariff principles, etc.) Several methods of defining the busy hour exist; here, the method of time- consistent busy hour was used. In a country the size of Germany the busy hour is almost independent of the geographic region.However, user traffic and the sum of call- and mobility-related signaling traffic are not immediately correlated, and may show different busy hours (Fig. 5).For traffic engineering purposes it must be decided whether different busy hours are considered for user traffic and signaling traffic, or both are considered at the busy hour for user traffic.MOBILITY TRAFFIC MODELThe mobility traffic model describes the effects of user mobility on user and signaling traffic. It includes procedures like location updating and handover. In the following, mobility is discussed in general terms and not further broken down into terminal and personal mobility .In Fig. 6 the average location updating (LU) and handover (HO) rate (the reference interface is the radio interface) of a mobile user in the busy hour are given for a metropolitan small cell environment.Mobility-related signaling rates are dependent on location and cell type. Hence, for cell and LA, planning tools are used that take into account transition probabilities of mobile users between neighboring cells . The transition probabilities can be found by measuring the handover structure between neighboring cells. However, comparing cell- by-cell measurements of handover and location updating rates, significant deviation may be discovered (e.g., ratio location updating /handover in cell A19.5, in cell B: 3.5, and in cell C: 2.4). Therefore, cells need further classification, such as metropolitan cells. urban cells, and cells containing high density traffic routes. Attributes of this kind can be stored in a mobility database and used in the actual cell-planning process.For the study of reference configurations, simplified mobility traffic models are useful which give a clear insight into basic relationships. A popular model is described in [9-111. Applying this model to measured location updating and handover rates allows approximation of the mobility-related reference loads for interesting reference configurations.REFERENCE LOADSreference loads represent the load R conditions at the incoming and out- going interfaces of the network elements. They can be based on practical measurements and may be formulated analytically for use in simulations and system testing. The specification of reference loads in cellular networks shows some differences from existing fixed networks.Examples are:A major portion of signaling transactions are independent of call/connection establishment . Therefor e, the characterization of a mobile user by his call attempt rate and traffic value is insufficient.The global behavior of a cellular net- work is composed of the reactions of multiple different network elements.The load generated by individual signaling transactions is determined by optional operator-defined settings,such asapplication of authenticationreallocation of temporary user identitiesa timer for periodic updatingdesign of location and paging areasIn this article only the load caused by switching-related traffic is considered. In a more comprehensive approach, the additional load caused by operation and main-tenance would also be taken into account.REFERENCE INTERFACESIt is essential for the evaluation of traffic event rates and occupancy times that the network interfaces to which these quantities are related be specified. Since most network elements do not measure the required quantities in a direct manner, the measurement results have to be transferred accordingly.In Figs. 7 and 8 two illustrative examples are given showing MOC and MTC attempt flows. The offered traffic streams are split into several substreams at the defined reference interfaces (Fig. 2). The user traffic on the radio interface is carried by traffic channels (TCH), for signaling common control channels (CCCH), and standalone dedicated control channels are used.The splitting ratios are given together with typical values in Table 1.REFERENCE UNITThe evaluation of the reference loads requires the definition of a basic reference unit, which can be applied consistently to all network interfaces. A reasonable unit for cellular net- works, due to its various signaling events and database entries, is one mobile user taken together with hiscall-and mobility-related behavior. This is different from ISDN exchanges, for example, where the definition of reference loads is based on average occupancy of incoming circuits and call attempt rate.POSSIBLE DEFINITIONS OF REFERENCE LOADSReference loads are defined which are used to evaluate the performance of the network elements. Two characteristic load conditions are proposed:Reference load A corresponds to the planned performance of a network element. The interarrival times and service times of communication events are modeled according to negative exponential distributions. This assumption is valid for centralized network elements like the HLR, VLR, MSC, and BSC. For a small BTS ((10 TCHs) this assumption is used by approximation.Reference load B considers higher load demands. A possible approach to model this load is to increase the signaling rates by 20 percent over those of reference load A.In the following, only reference load A is considered further.Reference Load of HLRs - The reference load of an HLR is defined by the maximum capacity of registered subscribers. Applying the call traffic and mobility traffic models gives the signaling load of an HLR.Reference Load of MSC/VLRs - Only combined MSC/VLRs are considered. The reference load, consisting of user and signaling traffic, is determined by the maximum capacity of registered subscribers. It has to be considered that an MSC/VLR may include various functionalities dependent on its use in the network, such as:MSC-F: MSC with normal function serving mobile usersG-IW-F: MSC with gateway func- tion providing specialized inter- faces (e.g., to a short message center),G-I-F: MSC with gateway function providing interfaces toifrom fixed networksR-I-F: MSC with SCCP relay functionT-U-F: MSC with transit functionT-S-F: MSC with transit function for for user traffic SS#7 trafficEspecially for an MSC with transit function, the capacity can be limited by the number of configurable interfaces.Reference Load of BSS - The refer- ence load of a BTS can be derived from the user traffic carried on the provided traffic channels with a predefined block- ing probability. With the user traffic intensity of a mobile user in the busy hour, the maximum number of served users and the signaling traffic can be calculated. The reference load of a BSC is given by the maximum number of mobile users served within the BSC area and their corresponding user and signaling loads.PERFORMANCE OBJECTIVEScellular networks have to guarantee a high quality of service for a large number of mobile users within a given geographical distribution. Therefore, appropriate sets of performance parameters have to be defined and then fulfilled under reference load conditions. In the recommendations of the ITU-T and related international standards four performance concepts are defined:.Quality of service (QoS) describes in general terms the collective effect of service performance as seen by the user.Network performance (NP) describes the abilities of a network or network portion to provide the functions related to communication between usersGrade of service (GoS) defines that portion of NP which measures the adequacy of network resources under rather general traffic conditions .Performance design objectives (PDOs) define performance requirements at the incoming and outgoing inter- faces of the individual network elementsCellular networks consist of a variety of different network elements; in most networks the equipment has been developed by various manufacturers. Therefore, the direction proposed by the concept of PDOs form a reasonable basis for defining performance parameters, since here specific reference loads and the input-output behavior of individual network elements are considered. PDOs can also be used by manufacturers to quantify capacities of individual equipment. It should be possible to verify the performance by system and acceptance tests. A first approach to defining PDOs is made in , but it needs refinement.Examples of performance parameters are system-related failure probabilities (e.g., probability of inadequately processed signaling transactions), processing delays of network elements (e.g., delay of a database access), and transfer delays (e.g., delay for relaying messages). In Table 2 typical values for various types of delay in the MSC/VLR and HLR are given.。
加油2024作文250字
加油2024作文250字英文回答：2024 is a significant year for many reasons. It marks the 100th anniversary of the founding of the Communist Party of China, and the 20th anniversary of the handover of Hong Kong to China. It is also the year in which China is expected to become the world's largest economy.These events will have a profound impact on China's future, and on the world. China's rise will continue to reshape the global political and economic landscape. Itwill also present challenges and opportunities for China's neighbors and partners.As China continues to grow and develop, it is important for us to work together to build a more prosperous and sustainable future for all. We must work to address the challenges that we face, and we must seize theopportunities that are presented to us.Together, we can build a better future for China andfor the world.中文回答：2024年是一个特殊的日子。
LTE题库
关于SDR说法错误的是（）。 4 空口协议栈中，IP头压缩功能位于（）层。 4 根据协议对LTE系统需求支持的定义，从驻留状态到激活状态的时延和零负载（单用户、单数据流）、小 2 3GPP要求LTE系统每MHz上行平均用户吞吐量应达到R6 HSUPA的（）倍。 2 我们常说的下行MIMO2发2收，下面说法正确的是： 2 在一个无线帧中，PBCH占用的RE个数为： 4 LTE中定义的最大物理小区ID个数为： 3 LTE的传输时间间隔TTI等于（ ）。 2 从驻留状态到激活状态，也就是类似于从Release 6的空闲模式到CELL_DCH状态，控制面的传输延迟时间 2 LTE协议中所能支持的最大RB个数为： 4 LTE上行采用SCFDMA是为了（ ） 1 下列对于LTE系统中下行参考信号目的描述错误的是： 4 S1接口不支持的功能是： 4 E-UTRA系统覆盖半径最大可达（）。 4 3GPP要求LTE系统每MHz下行平均用户吞吐量应达到R6 HSDPA的（）倍。 3 HARQ的信息是承载在（ ）上。 3 在Normal情况下，一个RB包含（ ）个子载波。 3 FFR中的中心用户CCU和边缘用户CEU是通过测量的（ ）与预先设定的门限值进行比较或服务小区和干扰 1 LTE协议规定的UE最大发射功率是： 2 对新建基站，勘察选址的一般原则中，以下错误的是： 1 在天线选取上，在普通城区一般选用水平半功率角为多大的天线？ 1 站点勘察准备的工作内容中，不包括如下的哪一项？ 4 在网规站点勘察中，距离测量的工具一般是： 2 站点选择规范里面，一般密集城区站点天线高度要求高出周围建筑高度平均多少米： 2 站点勘察要求在每个基站照几张照片： 4 以下哪项不是在站点勘察规划流程内： 4 《规划站点勘察计划》的输入前提是： 3 项目协调经理职责是： 4 仿真工程师职责是： 3 网规工程师职责是： 2 勘察工程师职责是： 1 站点勘察的输入信息是： 3 指南针测量规划站点中确定扇区天线方位角，以下步骤错误的是： 1 指南针的主要功能不包括： 4 在没有高精度电子地图的时候，通常会利用Google Earth的高精度卫星照片来进行区域边界的划定。然后 2 一般来说，利用Mapinfo来划分边界需要以下一些步骤：a.沿着站点分布稀疏、话务量低的区域来划分边 1 在生成扇区图层时，以下哪个信息不是必须的？ 2 美国位于西半球和北半球，迈阿密市某个站点的经度是80.2度，纬度是25.8度，那么用(x,y)的格式来表 3 以下哪款软件不能用于仿真？ 3 关于单站点验证测试的路线选择，下列说法错误的是。 4 单站点覆盖DT测试的目的，下列说法错误的是。 4 下列哪种说法是正确的。 1 单站验证测试过程中GPS的作用。 2 小区通过（）后，表明站点不存在功能性问题。 3 单站验证测试Log文件保存。 2 单站测试验证的重点是。 3 测试路线需要和()进行协商决定。 1 工程人员选择单站测试点的目的是。 2 单站点验证测试处于哪个网络优化流程之后。 1 单站验证测试中哪项不是空闲模式检查的内容。 3
创伤中心区域协同救治网络建设合作协议书
创伤中心区域协同救治网络建设合作协议书IntroductionThe establishment of a collaborative trauma center network is crucial for effective and efficient trauma care. In order to achieve this goal, it is necessary to form a comprehensive cooperation agreement among different medical institutions. This article outlines the key components of a trauma center network collaboration agreement.Background and SignificanceEfficient management of trauma cases requires a regional approach that involves multiple hospitals and healthcare providers. By establishing a collaborative trauma center network, healthcare facilities can streamline the process of identifying and transferring patients, as well as sharing resources and expertise. This approach minimizes delays in patient care and improves overall outcomes.Network StructureThe structure of the trauma center network should be clearly defined in the collaboration agreement. This includes identifying participating hospitals, their roles and responsibilities within the network, as well as any hierarchical relationships that need to be established.Coordinated Patient CareEffective coordination of patient care is critical in ensuring seamless transfer between different facilities within the trauma center network. The collaboration agreement should outline processes for timely patient handover, consistent communication channels, standardized protocols for evaluation and treatment, and information sharing practices.Resource SharingIn order to optimize trauma care delivery, the collaborative agreement should facilitate resource sharingamong participating institutions. This includes sharing of specialized equipment, personnel training programs, research initiatives, and best practices in trauma management.Quality Improvement InitiativesContinuous quality improvement is essential for providing optimal trauma care outcomes. The collaboration agreement should address mechanisms for monitoring performance indicators across participating institutions. Regular audits should be conducted to evaluate adherence toclinical guidelines and identify areas for improvement.Data Collection and AnalysisTo support evidence-based practice and decision making, it is important to establish processes for data collection, analysis, and reporting within the collaborative network. The collaboration agreement should detail data collection requirements, methods of data analysis, data-sharing protocols (while adhering to privacy regulations), andperiodic reporting procedures.Education and TrainingAn important aspect of any trauma center network is promoting education and training opportunities among healthcare professionals. The collaboration agreement should outline joint educational initiatives, such as conferences, workshops, and skill-sharing programs, to enhance the knowledge and skills of network participants.Dispute ResolutionIn any collaborative effort, disagreements may arise. It is important to have a clear dispute resolution mechanism in place within the collaboration agreement. This ensures that any conflicts or issues can be addressed promptly and efficiently, without affecting patient care.ConclusionIn conclusion, the establishment of a trauma center networkcollaboration agreement is vital for optimizing trauma care outcomes. By outlining key components such as network structure, coordinated patient care, resource sharing, quality improvement initiatives, data collection and analysis, education and training opportunities, as well as a dispute resolution mechanism, healthcare institutions can work together to provide efficient and comprehensive trauma care services within a defined region.翻译：介绍创建协同救治网络对于有效和高效的创伤护理至关重要。
香港回归周年英语作文
Furthermore, the handover has had a significant impact on Hong Kong's economy and identity. Under British rule, Hong Kong developed into a global financial center and a vibrant, multicultural city. The handover brought uncertainty about the city's economic future and its role in the international community. Additionally, there has been a palpable shift in Hong Kong's identity and cultural landscape as the city grapples with its colonial past and its place in modern China.
Related nursing English handover courseware
02
Handover process and standards
Preparation for shift handover
Check the patient list
The on duty nurse needs to check the patient list in the nursing station to ensure that all patients are included and their information is accurate
Related nursing English handover courseware
汇报人： 日期:
contents
目录
• The Importance of Handover • Handover process and standards • Common English expressions use • Handover under special circles • Training and Education for Han
The number should also provide necessary guidance to the family to
ensure that the patient's care is continuous and effective
Promote team communication and cooperation
Nursing diagnosis
The number's evaluation of the patient's condition and needs
Nursing intervention
备案项目经理辞职退出流程
备案项目经理辞职退出流程When a project manager decides to resign and leave a project, it can create a significant impact on the team and the overall progress of the project. The process of handling this situation requires careful planning and consideration to ensure a smooth transition for everyone involved. The first step in the process is for the project manager to formally submit their resignation to the appropriate authorities. This should be done in writing and include the effective date of their departure. The project manager should also schedule a meeting with their team to inform them of their decision and discuss the next steps.当项目经理决定辞职并离开项目时，这可能会对团队和项目的整体进展产生重大影响。
处理这种情况的过程需要仔细的规划和考虑，以确保每个参与方的顺畅过渡。
该过程的第一步是项目经理向相关管理部门正式提交辞职申请。
这应该以书面形式进行，并包括他们离职的生效日期。
项目经理还应该安排与团队成员会面，告知他们自己的决定并讨论接下来的步骤。
It is essential for the project manager to work closely with their replacement during the transition period to ensure a smoothhandover of responsibilities. The project manager should provide detailed documentation of their tasks, projects, and any ongoing issues to help the new manager get up to speed quickly. Additionally, the project manager should offer support and assistance to their replacement to help them adjust to their new role and ensure a successful transition for the team.在过渡期间，项目经理与自己的接替者密切合作至关重要，以确保责任的顺利交接。
fab 无尘室交接流程
fab 无尘室交接流程英文回答：Handover Process in a Fab Cleanroom.The handover process in a fab cleanroom is a critical step in ensuring the smooth and efficient operation of the facility. It involves the transfer of responsibilities and tasks from one shift to another, as well as the communication of important information regarding the status of the cleanroom and any ongoing processes.The handover process typically begins with a meeting between the outgoing and incoming shift personnel. During this meeting, the outgoing team provides a detailed update on the current status of the cleanroom, including any ongoing processes, equipment status, and any issues or concerns that need to be addressed. This information is crucial for the incoming team to effectively take over and continue the operations without any disruptions.In addition to the verbal update, the outgoing team also provides written documentation, such as shift reports and logbooks, to ensure that all relevant information is properly communicated and recorded. This documentation serves as a reference for the incoming team and helps them to stay informed about the activities and events that occurred during the previous shift.Once the verbal and written handover is complete, the incoming team conducts a thorough inspection of the cleanroom to verify the information provided and to ensure that everything is in order. This inspection includes checking the cleanliness of the cleanroom, the status of equipment and tools, and the overall compliance with cleanroom protocols and procedures. Any discrepancies or issues discovered during the inspection are promptly addressed and resolved before the incoming team fully takes over the responsibilities.After the inspection, the incoming team acknowledges the handover and assumes full responsibility for thecleanroom operations. They continue to monitor the cleanroom, perform necessary tasks, and communicate with other team members to ensure a seamless transition and ongoing operations.Overall, the handover process in a fab cleanroom is a critical aspect of maintaining the cleanliness, efficiency, and safety of the facility. It requires clear communication, thorough documentation, and careful inspection to ensurethat the transition between shifts is smooth and that the cleanroom operations continue without any disruptions.中文回答：无尘室交接流程。
电梯物业变更流程
电梯物业变更流程Dealing with the change in property management for an elevator can be a complex and time-consuming process. 电梯物业变更可能是一个复杂和耗时的过程。
It is important to consider the impact of this change on all stakeholders, including the building owners, tenants, and maintenance staff. 需要考虑这一变化对所有利益相关者的影响，包括建筑业主、租户和维护人员。
From negotiating contracts to ensuring a smooth transition, there are various aspects to consider when navigating through the process of elevator property management change. 从谈判合同到确保平稳过渡，在处理电梯物业管理变更过程中有许多方面需要考虑。
In this article, we will explore the different perspectives involved in the process and provide insights into effectively managing the change. 在本文中，我们将探讨参与此过程的不同角度，并提供有效管理变更的见解。
The first step in dealing with the change in elevator property management is to assess the current situation and identify the reasons for the change. 应对电梯物业管理变更的第一步是评估当前情况，确定变更的原因。
库房管理员工作交接流程
库房管理员工作交接流程As a warehouse manager, it is essential to have a proper work handover process in place to ensure a smooth transition between shifts and to minimize any potential errors or issues that may arise. 作为一名库房管理员，建立适当的工作交接流程对于保证班次之间的平稳过渡以及最小化可能出现的错误或问题至关重要。
First and foremost, effective communication is key in the work handover process. This includes providing clear and detailed instructions to the incoming shift regarding any pending tasks, ongoing projects, and important updates. Moreover, it is crucial to encourage open communication and feedback between the outgoing and incoming shifts to ensure a seamless transfer of responsibilities. 首要的是，有效的沟通在工作交接流程中至关重要。
这包括向接班班次提供明确而详细的指示，涉及任何未完成的任务，正在进行的项目以及重要的更新。
而且，鼓励即将离开的班次和即将到来的班次之间的开放沟通和反馈也是至关重要的，以确保责任的顺利转移。
Additionally, the use of technology and digital tools can greatly facilitate the work handover process. Implementing a digital platformfor documenting tasks, schedules, and inventory can help streamline the exchange of information between shifts, as well as provide a centralized location for storing important documents and data. 此外，利用科技和数字工具可以极大地促进工作交接流程。
前期物业与后期物业交接流程
前期物业与后期物业交接流程英文回答：Handover process between the initial property management and the subsequent property management is crucial for a smooth transition. Here is a step-by-step guide on how the handover process should be carried out:1. Communication and Planning:First and foremost, effective communication is essential between the initial and subsequent property management teams. Both parties should have a clear understanding of the handover process and its timeline. A detailed plan should be created to ensure a seamless transition.2. Documentation and Information Transfer:All relevant documents and information pertaining tothe property should be compiled and organized. This includes lease agreements, maintenance records, financial statements, and any other important paperwork. The initial property management team should provide these documents to the subsequent team in a timely manner.3. On-site Inspection:An on-site inspection should be conducted to assess the current condition of the property. Both teams should walk through the property together, noting any existing issues or areas that require attention. This will help the subsequent team to familiarize themselves with the property and plan for any necessary repairs or maintenance.4. Staff Introduction and Training:The initial property management team should introduce the subsequent team to the property staff members. This includes maintenance personnel, security staff, and any other relevant personnel. The subsequent team should be provided with necessary training and information regardingthe property's operations and protocols.5. Financial Handover:Financial matters, such as security deposits, rental payments, and utility bills, should be discussed and transferred between the two teams. Any outstanding payments or pending issues should be resolved before the handover process is complete. This ensures a smooth transition for both the property management team and the tenants.6. Tenant Communication:It is essential to maintain open lines of communication with the tenants throughout the handover process. The subsequent property management team should introduce themselves to the tenants, address any concerns or questions, and provide updated contact information. This helps to build trust and ensures a seamless transition for the tenants.7. Follow-Up and Evaluation:After the handover process is complete, it is important to conduct a follow-up evaluation to assess the success of the transition. Both teams should meet to discuss any challenges faced during the handover process and identify areas for improvement. This feedback can be used to refine the handover process for future transitions.中文回答：前期物业与后期物业交接流程对于一个顺利的过渡非常重要。
SQI
illustrates the different KPIs and the location in the receiving chain where they are measured [1].
The aim of our work is therefore to develop a parametric model for non-intrusive speech quality measurement. 4. DATA ANALYSIS In order to propose a new model, a large collection of real data has been considered. The speech samples have been obtained performing intrusive tests in a real GSM network, during which the correspondent measured transmission parameters have been stored. The MOS values of the output speech samples have been thence evaluated with the SQuad algorithm (an intrusive algorithm like PESQ but optimized for cellular communications [7]) implemented in the adopted equipment. Totally, 17235 speech samples were acquired, whose MOS distribution is reported in fig. 2. First of all, speech samples have been classified according to the adopted codec (for the most part HR and EFR) and to the speech direction (UL/DL), as reported in table 1, resulting in four data sets. The four correspondent MOS distributions fit the four peaks of the global MOS distribution, as expected in a stable GSM network. Subsequently, for each data set and for each considered parameter, the scatter plots have been drawn. One of these scatter plots is reported in fig. 3.
Handover Protocol for FPLMTS
MCF UIMF CCA’F TIMF TACAF BCAF BCFr TACF BCF SACF
SCF SRF SSF CCF’
Interactions
Interactions
MRRC
RRC
MRTR
RFTR
Radio Resource Control Plane Mobile Side Network Side
Figure 1. Functional Architecture of FPLMTS dispensible for FPLMTS to be integrated with ATM network. Current ATM network considers only for xed network, so there is a need of adaptation in ATM network 3]. For user mobility, the existing ATM network should adapt itself to support location management, authentication, handover and so on. In this paper, we focus on the signaling aspect at the usernetwork interface for handover. ITU has been actively working on a set of recommendations for FPLMTS, which will operate with the help of IN(Intelligent Network) 5]. Especially ITUT SG11 works on the signaling aspect for FPLMTS and produced two recommendations : Q.FNA and Q.FIF. Q.FNA 8] document describes the functional network architecture of FPLMTS, as depicted in Figure 1. Functional entities(FE) related to call control and handover are as follows.
The Impact of Promoting Access to Clean Water
The Impact of Promoting Access to CleanWaterAccess to clean water is a fundamental human right that is essential for the health and well-being of individuals and communities. The impact of promoting access to clean water cannot be overstated, as it has far-reaching benefits that touch on various aspects of life. From improving health outcomes to fostering economic development, ensuring access to clean water is crucial for the overall advancement of societies. One of the most significant impacts of promoting access to clean water is the improvement in public health. Contaminated water sources can harbor a multitude of harmful pathogens and pollutants that can cause a range of waterborne diseases such as cholera, typhoid, and dysentery. By providing accessto clean water, the incidence of these diseases can be significantly reduced, leading to a healthier population. This, in turn, can alleviate the burden on healthcare systems and improve overall quality of life. Furthermore, access to clean water is closely linked to sanitation and hygiene practices. Without clean water, it is challenging to maintain proper hygiene, which can lead to the spread of infectious diseases. By promoting access to clean water, communities can also improve their sanitation facilities and adopt better hygiene practices, further reducing the risk of disease transmission. This holistic approach to water, sanitation, and hygiene (WASH) is essential for promoting public health and preventing outbreaks of diseases. In addition to its impact on public health, promoting access to clean water can also have significant social and economic benefits. In many developing countries, women and children are primarily responsible for fetching water, often having to walk long distances to accesswater sources. This task can be physically demanding and time-consuming, taking away valuable time that could be spent on education or income-generatingactivities. By providing access to clean water closer to communities, especiallyin rural areas, women and children, particularly girls, can have more time to pursue education and other opportunities, breaking the cycle of poverty. Moreover, access to clean water is crucial for agricultural development and food security. Agriculture is a water-intensive industry, and farmers rely on access to cleanwater for irrigation and livestock. By promoting access to clean water for agricultural purposes, farmers can increase their crop yields and improve their livelihoods. This, in turn, can contribute to food security, as communities have a more reliable source of food and income. Furthermore, access to clean water can also have environmental benefits. In many regions, water sources are heavily polluted due to industrial activities, agricultural runoff, and improper waste disposal. By promoting access to clean water and implementing sustainable water management practices, communities can protect their water sources and preserve the environment for future generations. Clean water is essential for biodiversity and ecosystem health, and ensuring its availability is crucial for maintaining a balanced and sustainable environment. In conclusion, the impact of promoting access to clean water is multifaceted and far-reaching. From improving public health outcomes to fostering economic development and environmental sustainability, access to clean water is essential for the well-being of individuals and communities. By prioritizing investments in water infrastructure, sanitation facilities, and hygiene education, societies can unlock the full potential ofclean water and realize its transformative power. Ultimately, ensuring access to clean water is not just a matter of convenience but a fundamental human right that must be upheld for the benefit of all.。
The Impact of Technological Advancements
The Impact of Technological Advancements Technological advancements have had a profound impact on every aspect of our lives, from the way we communicate and work to how we entertain ourselves and even how we navigate the world. These advancements have brought about both positive and negative consequences, shaping the way we live and interact with the world around us. One of the most significant impacts of technological advancements is the way they have revolutionized communication. With the advent of the internet and smartphones, we can now connect with people from all corners of the globe instantly. Social media platforms have allowed us to stay in touch with friends and family, share our thoughts and experiences, and even build communities based on shared interests. However, this constant connectivity has also led to a decrease in face-to-face interactions, with many people preferring to communicate through screens rather than in person. In the workplace, technological advancements have transformed the way we work. Automation and artificial intelligence have made many tasks more efficient and streamlined, leading to increased productivity and profitability for businesses. However, this has also raised concerns about job security, as many traditional roles are being replaced by machines. The gig economy has also emerged as a result of technological advancements, offering flexibility and independence to workers but alsoinstability and uncertainty. Technological advancements have also had asignificant impact on entertainment and leisure activities. Streaming services have made it easier than ever to access a wide range of content, from movies and TV shows to music and podcasts. Virtual reality and augmented reality technologies have also opened up new possibilities for immersive gaming and experiences. However, there are concerns about the impact of excessive screen time on mental health and social relationships, as well as the potential for addiction to technology. In the field of healthcare, technological advancements have led to significant improvements in diagnosis, treatment, and patient care. Telemedicine has made it possible for patients to consult with healthcare providers remotely, reducing the need for in-person visits and increasing access to care for those in remote or underserved areas. Wearable devices and health tracking apps have also empowered individuals to take control of their own health and wellness. However,there are also concerns about data privacy and security, as well as the potential for technology to exacerbate existing healthcare disparities. Technological advancements have also had a profound impact on education, with online learning platforms and digital resources making education more accessible and personalized. Students can now access a wealth of information and resources at their fingertips, allowing them to learn at their own pace and in their own way. However, there are concerns about the digital divide, with many students lacking access to the necessary technology and internet connectivity to fully participate in online learning. There are also concerns about the impact of technology on traditional teaching methods and the role of educators in a digital age. Overall, technological advancements have brought about both positive and negative consequences, shaping the way we live, work, communicate, and entertain ourselves. While these advancements have undoubtedly improved many aspects of our lives, there are also concerns about the potential negative impacts, such as job displacement, social isolation, and health issues. It is important for us to continue to critically evaluate the role of technology in our lives and work towards harnessing its benefits while mitigating its drawbacks.。
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The Impact of Handover Protocols on the Performance of ABR Flow-Control Algorithms in a Wireless ATMNetworkM ICHAEL S AVORI´C,A DAM W OLISZDepartment of Electrical Engineering,TU Berlin,Einsteinufer25,D-10587Berlin,Germanysavoric,wolisz@ee.tu-berlin.deU DO R.K RIEGERT-Nova Deutsche Telekom,Am Kavalleriesand3,D-64295Darmstadt,Germanyudo.krieger@Abstract.Considering the high-speed data transfer by the ABR service class in a wireless ATM network,we investigate the impact of forward and backward hard handover protocols on the performance of the three rate-based ABRflow-control schemes Explicit Rate Indication for Congestion Avoidance(ERICA+),Fuzzy Explicit Rate Marking (FERM)and a new promising adaptation of FERM,called FERMA.We evaluate the performance of theseflow-control protocols by means of an object-oriented simulation model of a basic client-server architecture.Considering a standard hard handover protocol in a wireless ATM network,we show that our proposed enhanced signaling schemes based on a congestion-awareness concept and their integration into the ABR flow control have a positive influence on the stability and efficiency of the cell transfer by ABR connections.Moreover, we point out that the new adaptation of the fuzzy-control scheme FERM provides a promising alternative to the ERICA+ algorithm.Keywords:wireless ATM network,handover protocols,rate-based ABRflow control,fuzzy control.1I NTRODUCTIONIn the last decade,enormous technical efforts have been made to develop a platform enabling the integration of voice,data and multi-media communication.The Asyn-chronous Transfer Mode(ATM)provides one approach that looks very promising from the perspective of traffic engineering.Recently,however,there is the popular be-lief that the Internet paradigm will dominate the end-to-end communication of advanced endsystems.Neverthe-less,there is still interest in the development of ATM,at least as the underlying technology of a high-speed back-bone network.Moreover,it is obvious that several lessons learned during ATM studies may be transferred success-fully to the Internet world.Regarding the wireless access to such high-speed networks an improved mobility support is required.In this respect,the provision of an efficient wired and wireless access to an ATM backbone network is a challenging technical and economic issue(cf.[1],[2]).In this paper we consider high-speed data communica-tion in a wireless ATM(W ATM)network.For this purpose, we use the ABR service class that is specified in the ATM forum document Traffic Management Specification4.0(cf.[3]).The underlying W ATM architecture and the used pro-tocol stack of our study are derived from NEC’s prototype implementation W ATMnet and the ATM forum documents (cf.[4],[5],[6]).It includes a simplified version of the TDMA/TDD structure and the associated wireless MAC protocol of this system.Using an object-oriented discrete event simulation model of a basic client-server scenario in a wireless ATM network(seefigure1),we study the impact of the error-prone wireless communication channel and of mobility-management techniques determined by backward and for-ward hard handover protocols(cf.[4],[7],[8],[9],[10]) on the performance,i.e.efficiency,robustness and fairness, of the rate-based ABRflow-control algorithms ERICA+, FERM and our FERM-adaptation.The rest of the paper is organized as follows.Section 2sketches the basic principles of rate-based ABRflow-Submission1M.Savori´c,A.Wolisz,U.KriegerThe Impact of Handover Protocols on the Performance of ABR Flow-Control Algorithms in a W ATM Network(3)ABRwhereby ABR is the number of active ABR connec-tions traversing the switch.Finally,the switch-internal ex-plicit rate of an ABR connection is a combined calculationof the fair share,the periodically measured load factorincoming ABR cell rateM.Savori´c ,A.Wolisz,U.KriegerofFERMFigure 3:Membership function of the fractional queue growthrateofFERM Figure 4:Membership function of the fractional flow rateofFERMFor every control interval with the duration ofcell times the FERM algorithm in the ATM switch mon-itors the average ABR queue lengthand the ABR target cellrate TCR given by:TCR(”buffer (length)”),five linguistic values (”de-creasing fast”,”decreasing slow”,”zero”,”increasing slow”,”increasing fast”)for the queue growth rate (”rate of change”)and eleven linguistic rules to compute the weights of the linguistic values (”very little”,”little”,”medium”,”high”,”very high”)of the fractional flow rate.Then the fractional flow rate itself and after that the ABR target cell rate TCR (”flow rate”)are computed by (10).Before every control interval the weights of all lin-guistic values are set to 0.Then the weightsand the weights ,,of the queue growth rate are determined.For the linguistic rule (R11),for instance,the last step of the computation can be expressed by (see (9)):(12)Since the membership function of has in this casethe same symmetrical shape for every linguistic value ofand equal distances between them,(12)can be trans-formed intoThe Impact of Handover Protocols on the Performance of ABR Flow-Control Algorithms in a W ATM NetworkM.Savori´c,A.Wolisz,U.KriegerThe Impact of Handover Protocols on the Performance of ABR Flow-Control Algorithms in a W ATM NetworkBER E BM.Savori´c,A.Wolisz,U.KriegerFERMcfTable2:Results for VS/VD ABRflow controlERICA+FERMAHOOOR, the95%confidence interval cf calculated by batch-means and the variance of the queue length are shown only for the base station with the highest maxi-mal queue length during the simulation run.HOdenotes the total number of performed backward handovers and in parenthesis the total number of performed (good)forward handovers for all mobile terminals.OOR denotes the total number of OOR-RM cells caused by con-gestion in the MSC and in the base stations and in parenthe-sis the total number of OOR-RM cells caused by the used handover protocol.For all runs between and MSC information messages are sent from the base stations to the MSC,caus-ing an additional transfer rate of about10cells per second between the base stations and the MSC.The followingfigures12to20are selected from the base station with the highest maximal queue length during a certain run.The results of these experiments show that FERM and particularly its adaptation FERMA are ef-fective and compare favorably with ERICA+regarding the following important criteria:Efficiency:In thefigures12,14,16,18,19and20we show typical outcomes of the queue length process in the considered base station.Without any exception high peaks reflect the impact of a forward handover.The corresponding histograms(seefigures13,15and 17)illustrate that FERM can control the queue length well on the desired low level and that ERICA+and the FERM-adaptation can control the queue length well around the chosen target point.For instance,for the selectedfixed queueing delay without any CBR or VBR background traffic load and with a mean BER of in the related radio link a base station has a target queue length of ap-proximately34ABR cells.The combination of handover signaling and ABRflow control together with an optional VS/VD-approach in the MSC has the expected positive influence on each algo-rithm.The ratio of the maximal and the mean queue length in a simulation run is defined by:(16)For the three considered ABRflow-control algorithms we getERICA+FERMFERMAwhere the results for VS/VD are stated in parenthesis.Despite of the low mean queue length FERM cannot prevent high values at all.For the same target point and a comparable variance our FERM-adaptation is slightly su-perior to ERICA+.Robustness:We are mainly interested in the stability and efficiency of our FERM-adaptation.The performed sim-ulation runs show that the FERM-adaptation implements8ETTThe Impact of Handover Protocols on the Performance of ABR Flow-Control Algorithms in a W ATM NetworkM.Savori´c,A.Wolisz,U.KriegerThe Impact of Handover Protocols on the Performance of ABR Flow-Control Algorithms in a W ATM NetworkM.Savori´c,A.Wolisz,U.KriegerTable4:Parameters of the linguistic variable(see figure6)12345。