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Search Results: 1 - 10 of 280628 matches for " 李杰 "
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 李向杰 Advances in Applied Mathematics (AAM) , 2013, DOI: 10.12677/AAM.2013.22012 Abstract: 本文基于低温环境下平行圆柱孔结构的纺织材料热湿传递稳态模型，研究了一类双层纺织材料厚度设计反问题。首先给出了一个双层纺织材料热湿传递稳态模型，并采用有限差分方法求解该问题。然后，根据服装热湿舒适性指标，将纺织材料内层厚度看成一个未知量，提出了一类双层纺织材料厚度设计反问题，将该反问题归结为一个最大概率最小模问题，采用罚函数法将该约束优化问题转换为无约束的优化问题，并采用粒子群算法求解。数值结果说明了双层纺织材料厚度设计反问题提法的合理性，以及粒子群算法的有效性和鲁棒性。This paper studies a new inverse problem of estimating bi-layer textile fabrics thickness based on a steady-state heat and moisture transfer model. We first present a heat and moisture transfer model for bi-layer textile materials with boundary conditions and solve them by finite difference method. According to the requirement of clothing’s thermal and moisture comfort, we formulate the inverse heat and moisture transfer problem that estimate the thickness of inner fabric as a minimum norm problem with a maximum probability constraint model. We use a static penalty method to convert the constrained problem into an equivalent unconstrained minimization problem and obtain the solution for the optimization problem by a stochastic search method, known as particle swarm optimization algorithm. Numerical experiments show that our new model is quiet acceptable, and the proposed numerical method’s validity and robustness.
 Smart Grid (SG) , 2014, DOI: 10.12677/SG.2014.43014 Abstract: 本文研究的重点是电力通信网业务部署模块的设计与实现。业务部署是SDH网络规划的一个重要环节，SDH网络的设备以及链路搭建的主要目的正是为了承载业务。本文首先介绍了电力通信网规划这一概念提出的背景、电力通信网规划仿真系统的技术基础、电力通信网规划仿真系统的功能分析。其次，对仿真系统的业务部署模块进行了需求分析和概要设计。再次，本文针对电力通信网规划仿真系统业务部署模块进行了详细设计，提出了配置管理仿真系统的实现架构，并阐述了各子模块之间的关系。最后基于Eclipse和FLEX开发工具实现了该仿真模块。 This research focuses on the design and implementation of service deployment module in grid power communication network. Service deployment is an important part of SDH network planning, as the main purpose of device and link deployment in SDH network is to undertake the businesses. This paper introduces the background of the power communication network planning, the technology of power communication network planning simulation, and the function analysis of the simulation system. Then this paper makes the requirement analysis and preliminary design of the service deployment module of the simulation system, and shows the detailed design of the deployment module with the architecture of the configuration and management simulation system, explaining the relationship between the various sub-modules. Finally, this paper shows the implementation of this simulation module based on Eclipse and FLEX.
 李杰, 陈进, 尹正杰 Journal of Water Resources Research (JWRR) , 2014, DOI: 10.12677/JWRR.2014.35046 Abstract: 为评价金沙江梯级水库联合调度对下游的影响，以屏山水文站1951~2011年的实测逐日流量序列为基础，通过梯级水库联合调度运行模拟得到模拟调度逐日流量数据，采用基于流量历时曲线的生态流量指标法(eco-flow metrics)对比调度前后水文情势变化特征，分析金沙江梯级水库联合调度在长系列、丰平枯典型年以及自然四季中对生态水文过程的影响。同时对比通过变动范围法(Range of Variability Approach, RVA)分析水文情势得到的结果，讨论生态流量指标法的适用性。结果表明，金沙江梯级水库运行会对水库下游水文情势的产生较为显著的影响，主要体现在低流量以及枯水期的变化之上；生态流量指标和RVA在水文情势分析结果上具有一定的相似性，两者结合一起可以更好地分析水文情势的变化。To evaluate the flow regime change in the lower Jinsha River after the operation of cascade reser-voirs, the change characteristics of flow regime in different periods were evaluated based on ob-served daily flow series at Pingshan hydrological station from 1951 to 2011 and the scheduling simulation data from 2031 to 2091 by using the eco-flow metrics based on flow duration curve. Meanwhile, the applicability of eco-flow metrics to evaluate the flow regime was discussed and compared with the results of flow regime obtained by using Range of Variability Approach (RVA). The results show that the operation of cascade reservoirs will lead to a significant change in flow regime at Pingshan hydrological station, which is mainly reflected in low flow and changes in low flow period. The results of flow regime obtained by using eco-flow metrics and RVA have a certain degree of similarity. Therefore, combination of the two groups of metrics provides a sufficient measure of the changes in the flow regime.
 Journal of Water Resources Research (JWRR) , 2012, DOI: 10.12677/JWRR.2012.16077 Abstract: 本文利用黑河流域内9个气象站1961~2010年的极端温度资料，运用气候倾向率和Mann- Kendall趋势检验法对流域的年、季极端最高气温和极端最低气温进行了分析研究。结果表明，在年变化上，近50a黑河流域极端气温总体上呈上升趋势，且极端最低气温的变化幅度明显大于极端最高气温的变化幅度，其中山丹站极端最低气温的上升倾向率达到了0.95℃/10a；流域下游地区的年极端最低气温变化幅度较中上游大部分地区显著。在年代际变化上，流域年极端最低气温上升趋势大体始于70年代，而年极端最高气温上升趋势始于80年代末。流域的极端温度变化趋势存在着明显的季节性差异，极端最高气温变化最显著的季节是冬季，极端最低气温变化最显著的季节是秋季。 Based on the measured extreme temperatures of 9 stations from 1961 to 2010, the changes of an- nual and seasonal extreme temperatures in Heihe River basin were analyzed by using the trend slope and Mann-Kendall method. The results showed that the generally increasing trends of annual extreme temperatures occurred all over the basin and the increase of extreme minimum temperatures were greater than those of extreme maximum temperatures, especially the extreme minimum temperature in Shandan station with an increasing rate of 0.95？C/10a. The increase of annual extreme minimum temperatures in lower reaches was greater than those in upper and middle reaches of basin. The extreme minimum temperatures began to increase at the beginning of1970’s, while the extreme maximum temperatures at the end of1980’s. The seasonal differences in trends of extreme temperatures were clear, and the most obvious season was winter in trends of extreme maximum temperatures and autumn in trends of extreme minimum temperatures.
 李杰 工程力学 , 1996, Abstract: 本文发展了一类用于随机结构系统动力分析的扩阶系统方法。基于随机空间的正交展开理论,文中推导给出了扩阶系统动力方程的一般公式。这组公式可以适用于同时具有随机质量、随机阻尼、随机刚度参数的多自由度动力系统。通过引入虚拟结构的概念,文中建议了形成扩阶系统动力矩阵的有限元方法。通过对比算例分析,证实了扩阶系统方法的可行性与可靠性。最后,讨论了一个很重要现象:随机系统均值反应与相应均值参数系统反应之间的差异并指出了此差异的意义。
 李杰 煤炭科学技术 , 2014, Abstract: 为了有效治理采空区上隅角瓦斯，针对九里山矿16041工作面采用定向高位长钻孔抽采上隅角瓦斯的现状，利用UDEC软件对工作面上覆岩层塑性区进行模拟，并结合现场试验，确定了定向高位长钻孔最佳抽采位置应为距离顶板13~25m内。抽采结果表明：工作面上隅角平均瓦斯体积分数从078%下降到031%，回采工作面推进速度从36m/d提高到48m/d，提高了约133倍，保证了工作面回采安全。
 李杰 公路交通科技 , 1998, Abstract: 以汽车动力总成橡胶悬置系统为研究对象,建立了汽车动力总成橡胶悬置系统的动力分析方程、固有特性分析方程及振动耦合特性分析公式,并用于某汽车动力总成橡胶悬置系统的固有特性分析和振动耦合特性分析.
 李杰 力学学报 , 1996, DOI: 10.6052/0459-1879-1996-1-1995-303 Abstract: 提出了随机结构系统反应的子空间次序正交分解的思想．基于这一思想，文中导出了一类用于考虑随机激励的随机结构复合随机振动分析的扩阶系统方法，从而可以应用传统的确定性结构随机振动各种分析方法求解复合随机振动问题．作为特例，本文给出了使用模态分析法求解的过程．将文中算例与随机模拟结果相比较，证实了本文思想与方法的实用性．
 李杰 财会月刊 , 2007, Abstract: 一、设计现金流量表审计程序的一般原则　　1.先易后难。根据先易后难的原则，审计现金流量表时，应先审计投资活动、筹资活动产生的现金流量，后审计经营活动产生的现金流量。而在审计同一类现金流量时，应先审计容易查找的项目，后审计比较复杂的项目。　　2.先下后上。根据这一原则，审计执行38项具体会计准则（以下简称“新准则”）的企业的现金流量表时，应从“期末现金及现金等价物余额”项目开始，然后依次审计“期初现金及现金等价物余额”、“现金及现金等价物净增加额”、“汇率变动对现金及现金等价物的影响”，以及筹资、投资、经营活动产生的现金流量。审计执行《小企业会计制度》、《企业会计制度》和行业会计制度的企业的现金流量表时，也按此顺序审计。
 李杰 财会月刊 , 2007, Abstract: 　　本文从汇率变动对现金影响的因素分析入手，采用案例分析法，讨论现金流量表中“汇率变动对现金及现金等价物的影响”项目的填报。　　【关键词】现金流量汇率查账法倒轧法因素法　　《企业会计准则第31号——现金流量表》规定：“外币现金流量以及境外子公司的现金流量，应当采用现金流量发生日的即期汇率或按照系统合理的方法确定的、与现金流量发生日即期汇率近似的汇率折算。汇率变动对现金的影响额应当作为调节项目，在现金流量表中单独列报。”　　《〈企业会计准则第19号——外币折算〉应用指南》规定：“即期汇率，通常是指中国人民银行公布的当日人民币外汇牌价的中间价。企业发生的外币兑换业务或涉及外币兑换的交易事项，应当按照交易实际采用的汇率（即银行买入价或卖出价）折算。即期汇率的近似汇率，通常采用当期平均汇率或加权平均汇率等。”　　为了说明问题，本文结合以下案例展开分析。
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