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111.
背景和意义劳动保障部门作为统一管理和组织协调社会劳动力,统筹城乡就业,规划、引导劳动力市场的发展,组织建立健全就业服务体系,负责社会保障基金的缴纳、记录、核算、支付的部门,运用信息技术来实现劳动保障管理工作的电子化、自动化和网络化,更科学、更迅速、更准确地汇集、加工、传递、运用各类信息,是社会保障电子政务系统建设的重要内容,也是加快由行政管理向社会服务转化的突破口。随着社会保障电子政务系统建设的不断深入以及网络技术的发展,基于Internet的网上应用已逐步开展。如参保单位的网上申报、网上缴费以及信息查询等。这…  相似文献   
112.
In this letter, we propose a subspace based detection method for space-time block codes (STBC) wedded with ultra-wideband (UWB) transmissions. Without the need of channel information, the proposed algorithm yields the estimation of transmitted symbols by minimizing some quadratic form built on the orthogonality between signal and noise subspaces. Simulations in flat-faded application scenarios show that the subspace method can achieve the same diversity and a loss of about 2 dB at the 10/sup -3/ level with more than four successive space-time codes being decoded jointly, compared to the coherent decoding algorithm.  相似文献   
113.
Grain Growth Behavior of 5Cr21Mn9Ni4N Steel Micro-Alloyed by Rare Earth   总被引:2,自引:2,他引:0  
Grain growth behavior of 5Cr21Mn9Ni4NRE steel was experimentally studied at various solid solution treatment temperatures and holding for different times. The experimental results show that the 5Cr21Mn9Ni4NRE steel has the feature of sharp austenite grain coarsening after solid solution treatment at the temperature above 1150 ℃. RE added in the steel has the benefit to restrain grain growth and increase grain growth activation energy.  相似文献   
114.
T.C. Ovaert  H.S. Cheng 《Wear》1991,150(1-2):275-287
The unlubricated sliding wear behavior of non-reinforced polyetheretherketone (PEEK) and a PEEK-carbon fiber (PEEK-Cf) composite was investigated under lightly loaded conditions against mild steel counterfaces. The results showed the occurrence of a relative minimum in wear for the non-reinforced PEEK-mild steel system, resulting from interfacial film formation. In addition, the wear particle morphology changed substantially as the counterface became rougher. For PEEK on abraded mild steel, attempts were made to correlate the wear rate with the average asperity radius model of Hollander and Lancaster. The PEEK-Cf composite, when compared under similar experimental conditions, also displayed a relative minimum in wear; however, it occurred against rougher counterfaces compared with those corresponding to the non-reinforced PEEK. In this case, the relative wear and transferred wear debris morphology reflected the addition of the carbon fibers.  相似文献   
115.
以自行研制的一种复合酶为软化剂 ,研究了 p H值、反应温度、反应时间、酶用量以及铬含量对猪蓝湿皮软化效果的影响 ,其软化效果以软化液中羟脯氨酸的浓度增量来表征。研究结果表明 :通过蓝湿皮软化来改善成品革的质量是可行的 ,而且有明显的效果 ;以软化液中羟脯氨酸的浓度来表征软化效果是一个有效的方法 ;当用该复合酶软化猪蓝湿皮时 ,最适 p H值范围为 6 .0 - 6 .5 ;反应温度在 4 0 - 6 5℃之间时 ,软化效果随温度的升高而增大 ;在 5 5℃条件下 ,该酶有很好的热稳定性 ,能长时间保持活力不衰减 ;最适酶用量为 30 0 U/ g试样 ;蓝湿皮的铬含量对软化效果有影响 ,用该方法处理的蓝湿皮 ,其铬离子质量含量一般应≤ 2 .5 %。  相似文献   
116.
基于EAI的多层分布式应用与实现   总被引:5,自引:0,他引:5  
针对目前大型企业各类应用迅速增加但应用之间缺乏有效通信的问题,采用企业应 用集成(EAI)技术,提出了4层分布式应用体系结构,实现流程自动化和松耦合的应用集成.文中首先从EAI技术和常见解决方案出发,详细阐述了表示层、企业门户、EAI总线层和数据源层的功能及软件结构,并结合电信业务运营支撑系统的实际需求,给出了J2EE平台下的应用实例开发.利用组件和容器的技术构建企业门户,通过工作流和企业Java组件(EJB)技术实现EAI总线,借助资源适配器完成应用之间的互连互通.该系统现已投入实际运行,取得了良好的应用效果.  相似文献   
117.
We give a random optimization (RO) algorithm to optimize a real‐valued function of n real variables. During the optimization process, interpolation points are examined to follow valleys, and jumps to new starting points are executed to avoid numerous iterations in local minima. Convergence with probability one to the global minimum of a function is proved. The proposed RO method is a simple, derivative‐free and computationally moderate algorithm, with excellent performance compared to other RO methods. Seven functions, which are commonly used to test the performance of optimization methods, are used to evaluate the performance of the RO algorithm given here. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
118.
In this paper, we discuss some strategies for identifying unrepairable memories, and from that to introduce a novel theorem that can make more precise identification. A new algorithm for searching repair solutions is also proposed, which characterizes the rows, and columns of defective memory cells with revised effective coefficients. We have simulated it on many generated example maps, and compared it with the previous algorithms to verify its efficiency. It's combined with those arranged strategies of judging unrepairability to generate a complete flow. The complete algorithm has also been run on many examples with various memory sizes, defect numbers, and distribution types. The simulation results further show that identifying unrepairability in advance can help the reconfiguration procedure run much faster than searching solutions directly.  相似文献   
119.
Frequency notched printed slot antenna with parasitic open-circuit stub   总被引:2,自引:0,他引:2  
Lui  W.J. Cheng  C.H. Zhu  H.B. 《Electronics letters》2005,41(20):1094-1095
A new frequency notched ultra-wideband microstrip slot antenna with a parasitic tuning stub is proposed. The antenna is similar in configuration to a conventional microstrip slot antenna; by introducing a parasitic open-circuit tuning stub, flexible frequency notched function is achieved. Several properties of the antenna, such as frequency notched function, antenna transfer function and gain, have been investigated. As is reported, the operation bandwidth of the antenna is 2.91-11.16 GHz, in which a frequency notched band of 5.10-5.85 GHz has been achieved. Furthermore, good ultra-wideband linear transmission performance over the entire operation frequency range has also been achieved.  相似文献   
120.
Many dams in the USA have outlived their intended purpose and an increasing number are being considered for removal. Yet, quantitative studies of the potential physical, biological and ecological responses are needed to assess dam removal decisions. In this paper, the responses of migratory walleye (Sander vitreus) to increased spawning habitat availability as a result of dam removal was studied by comparing scenarios with and without a high‐head dam in the Sandusky River (Ohio), a major tributary to Lake Erie. A conceptual, ecological model was proposed to define the relationship between hydrodynamics and walleye spawning, egg hatching, larval drift and survival. A mathematical, ecological model of the early life‐history stages was then developed and coupled with time series of depth and velocity predictions over the spawning grounds from a 1‐D hydrodynamic model. Model simulations were run for 1984–1993 for both the with‐ and without‐dam scenarios to assess the potential benefit of dam removal. The simulation results demonstrated that velocity, depth and water temperature are major factors influencing adult walleye spawning success. Without the dam, 10 times the amount of spawning habitat would be available for walleye to spawn. This increase in spawning habitat area resulted in up to five times the total egg deposition and seven times the larval output to the nursing grounds, based on the assumption that 5% of the walleye population of Lake Erie migrated up the Sandusky River to spawn. We concluded that the spawning habitat in the current condition (with the dam) is limiting and additional spawning habitat upstream could significantly increase the number of larval walleye drifting to Lake Erie. The model sensitivity analysis showed that the number of walleye migrating up the river in spring is the dominant factor for larval recruitment to the lake. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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