摘要：Guanting reservoir（Gr） is one of the most important water sources for Beijing and neighboring *** to water pollution,it was withdrawn from the system to supply Beijing drinking water;however,after a thorough treatment process,Gr was made a reserve water source since *** develop a comprehensive and quantitative analysis of water yield and purification services in the Gr watershed,this study selected two time periods：the period when Gr was withdrawn from the system supplying local drinking water and the period that it has been designated a reserve water *** In VEST model was used to evaluate the quantities of water yields,and total nitrogen and total phosphorus outputs from 1995 to 2010 Additionally,the spatiotemporal variations of water yield services and water quality purification services in the Gr watershed were *** results showed that water yield services in the Gr watershed first weakened and then became stronger,but weakened overall during the years 1995 to *** yield capacity in the basin decreased from 1.89×10^9 m3 in 1995 to 1.43×10^9 m3 in 2010（a drop of 24.0% in total）.Water quality purification services also showed the same *** nitrogen output decreased from 4028.7 t in 1995 to 3611.4 t in 2010,while total phosphorus decreased from 379.7 t in 1995 to 354.0 t in *** and phosphorus purification services were enhanced by 10.4% and 6.8%,*** in the climate and land use were the main factors which lead to the changes in the water yield service in the Gr *** intended to protect water resource have matched the varying trends of water quality purification services during different *** one hand,the research results provide a foundation to identify key fields for eco-compensation in the Guanting reservoir *** another hand,the ecosystem service value will increase on the basis of eco-compensation criteria through setting the scenarios of returning farmland to forest and

摘要：A dynamic programming-sequential quadratic programming(dP-SQP)combined algorithm is proposed to address the problem that the traditional continuous control method has high computational complexity and is easy to fall into local optimal *** solve the globally optimal control law sequence,we use the dynamic programming algorithm to discretize the separation control decision-making process into a series of sub-stages based on the time characteristics of the separation allocation model,and recursion from the end stage to the initial *** sequential quadratic programming algorithm is then used to solve the optimal return function and the optimal control law for each *** simulations of the combined algorithm and the traditional algorithm are designed to validate the superiority of the combined ***-following and cross-conflict simulation examples are created to demonstrate the combined algorithm’s adaptability to various conflict *** simulation results demonstrate the separation deploy strategy’s effectiveness,efficiency,and adaptability.

摘要：A set of acoustic optimization design methods is established by combining the flow field deterioration theory and the acoustic analogy theory,and applied to the acoustic optimization design of high-speed train *** results show that the streamline bodies of the head/tail car are the most important sound sources,respectively,accounting for 23.7%and 33.7%of the total sound *** with the streamline body of tail head,the streamline body of head car is more biased towards high frequency for the sound source *** A-weighted radiated noise of the train body is characterized by broadband sound(mainly in the range of 1-4 kHz)and peak features(especially at 2 kHz).The snow-plough with the maximum expansion length can mitigate the strong peak effect of the sound at 2 kHz,reduce the total sound energy,and show the best acoustic radiation performance in the four *** numerical computation model was checked by the wind tunnel test results.

摘要：In order to improve the design and implementation quality of web service compositions,formal methods are used to model them and certain properties are *** （web service interface control flow automata）is used to model web services,especially the control flow and possible interactions with other web services.A web service composition consists of a set of interacting *** global behavior of web service compositions is captured by NWA（nested word automata）.A variation of the depth-first search algorithm is used to transform a set of WCFA into an *** formulae and call stacks at each node of NWA are computed by a path-sensitive reachability *** properties,call stack inspection properties and pre/post-conditions of service invocations are described by *** verification of these assertions is carried out by an automated SAT tool.

摘要：There have been a great demand for a suitable and convenient method in the field of buckling analysis of stiffened ship structures, which is essential to structural safety assessment and is significantly time-consuming. Modeling, buckling behaviors and ultimate strength prediction of stiffened panels were investigated. The modeling specification including nonlinear finite element model and imperfections generation, and post-buckling analysis procedure of stiffened plates were demonstrated. And a software tool using set-based finite element method was developed and executed in the MSC. Marc environment. different types of stiffen panels of marine structures have been employed to investigate the buckling behavior and assess the validity in the estimation of ultimate strength. A comparison between results of the generally accepted methods, experiments and the software tool developed was demonstrated. It is shown that the software tool can predict the ultimate capacity of stiffened panels with imperfections with a good accuracy.

摘要：分析了传统的综合客运枢纽布局优化模型,同时增加运输模式与中转能力的约束条件,提出了改进后的综合客运枢纽布局优化模型,并设计了改进的遗传算法对其求解。应用LINGO软件进行有效性检验,分别计算了8节点与50节点Solomon标准测试数据,并将改进模型与经典算法进行比较。计算结果表明:当应用LINGO软件计算8节点Solomon标准测试数据时,平均运算时间为5 043s,最优成本为1 952 418元,应用遗传算法与MATLAB软件计算的平均运算时间为62s,最优成本为1 955 900元;当应用遗传算法与MATLAB软件计算50节点Solomon标准测试数据时,平均运算时间为574s,最优成本为8 500 600元;当计算25节点的AP数据且枢纽节点数量为3时,平均运算时间为612s,最优成本为155 148元,比经典算法降低了108元。可见,改进模型有效。

摘要：类脑计算是后摩尔时代集成电路发展的重要方向,开发能够模拟理想突触行为的人工突触器件是构建神经元-突触-神经元连接方式的类脑计算芯片的关键.铁电薄膜材料具有独特的非易失性极化,极化的可塑性与生物突触的可塑性十分类似,因此铁电突触器件近年来受到了广泛关注.本文从器件突触功能模拟和类脑计算应用两个方面对铁电突触器件的研究进展进行了综述.结果表明,铁电突触器件具有两端和三端两种典型结构.除了能有效模拟生物突触功能,铁电突触器件还具有结构简单、功耗低、稳定性高、开关比大及编程速度快等优点.在应用层面,基于铁电突触的神经网络在图像识别方面的研究取得了一系列进展.此外铁电突触还被应用于触觉和视觉仿生.虽然取得了丰富的研究进展,但铁电突触器件目前仍停留在原理的提出和实验验证阶段,在突触性能调控机理、可靠性评价标准、阵列结构优化设计、高密度集成工艺、神经形态计算架构设计、新颖应用场景拓展等方面的研究都存在不小的挑战,这些也是未来铁电突触研究所要聚焦的方向.

摘要：Nickel-based layered double hydroxides(LdHs)are promising electrode materials in the fields of energy storage(supercapacitors)and conversion(urea oxidation).The rational construction of atomic and electronic structure is crucial for nickel-based LdHs to realize their satisfactory electrochemical ***,we report a facile,ecofriendly,one-step synthesis process to construct petal-like oxygen-deficient NiAl-LdH nanosheets for hybrid supercapacitors(HSCs)and urea oxidation reaction(UOr).The asprepared NiAl-LdH nanosheets with rich oxygen vacancies possess a large specific surface area of 216.6 m2 g^(-1) and a desirable electronic conductivity of 3.45×10^(–4)S cm^(-1) to deliver an ultra-high specific capacitance of 2801 F g^(-1)(700 C g^(-1))at 1 A g^(-1).Furthermore,high specific energy of 50.0 W h kg^(-1) at 400 W kg^(-1) and excellent cycle stability with 91%capacitance retention after 10,000 cycles are achieved by the NiAl-LdHs/CFP(carbon fiber paper)(+)//YP-80F(a commercial activated carbon)(–)***,NiAl-LdH nanosheets also work as an efficient electrocatalyst for UOr,which only requires 1.42 V *** hydrogen electrode to drive 10 mA cm^(–2) in 1 mol L^(-1) KOH with 0.33 mol L^(-1) *** remarkable performance is superior to most reported values of previous candidates owing to the thin structure of NiAl-LdH nanosheets for exposing more active sites and abundant oxygen *** addition,various reaction parameters are investigated to optimize the electrochemical *** general,this work paves a new way for the architecture of multifunctional nanostructured energy materials.

摘要：The measures of path charge are important considerations in traffic assignment of road networks. Factors, such as travel time, fixed charge and traffic congestion which affect road users＇ choices of trip paths, are analyzed. Travelers usually decide their trip paths based on their personal habits, preferences and the information at hand. By considering both deterministic and stochastic factors which affect the value of time （VOT） during the process of path choosing, a variational inequality model is proposed to describe the problem of traffic assignment. A lazy loading algorithm for traffic assignment is designed to solve the proposed model, and the calculation steps are given. Numerical experiment results show that compared with the all-or-nothing assignment, the proposed model and the algorithm can provide more optimal traffic assignments for road networks. The results of this study can be used to optimize traffic planning and management.

摘要：Hydroxyapatite(HA)nanoparticles and silver(Ag)nanoparticles are expected to enable desirable bioactivity and antibac-terial properties on biopolymer ***,interfacial adhesion between HA/Ag and the biopolymer is poor due to the large physicochemical differences between these *** this study,poly L-lactic acid(PLLA)powder was first surface-modified with bioactive polydopamine(PdA)in an alkaline ***,HA and Ag nanoparticles were grown in situ on the PdA-coated PLLA powder,which was then adhered to the porous bone scaffold using a selective laser-sintering *** showed that HA and Ag nanoparticles were homogenously distributed in the matrix,with enhanced mechanical *** body fluid bioactivity tests showed that the in situ grown HA-endowed scaffold shows excellent *** vitro tests confirmed that the scaffold exhibits favorable biocompatibility with human umbilical cord mesenchymal stem cells,as well as strong antibacterial activity against Gram-negative Escherichia ***,in vivo assays indicated that the scaffold promoted bone generation,with a new bone area fraction of 71.8%after 8 weeks’implantation,without inflammation.