八地脚螺栓刚性塔座板的承载力

随着中国电网技术的发展，杆塔负荷越来越大，八地脚螺栓塔座板应用越趋普遍。但现有计算理论与实际情况不符，为了使八地脚螺栓塔座板的计算方法合理、可靠，通过试验对八地脚螺栓刚性塔座板承载力进行了研究，同时借助有限元对构件进行了参数化分析。结合经典力学理论、试验及有限元数据，提出了全新的计算方法，引入了等效计算宽度和有效力臂的概念，充分考虑了底板刚度，屈曲后强度和垫板对承载力的影响，对工程设计具有指导意义。     

计及电网停电风险的输电线路动态融冰决策方法

电网发生大面积冰灾情况时，多条输电线路存在覆冰故障隐患，电网稳定运行受到严重威胁，需要提前制定输电线路融冰方案，合理安排融冰顺序。针对此问题，分析输电线路覆冰继续运行给电网带来的停电风险，将与待融冰输电线路相关联的变电站的电气主接线展开，将传统削负荷模型改进后应用于输电网与变电站主接线的组合网络，建立断路器可靠性模型，计算靠后融冰线路因继续运行的电网停电风险；利用计及风速及降雨影响的输电线路覆冰增长预测模型，计算输电线路的覆冰率，根据覆冰率门槛值确定待融冰线路集，基于覆冰严重度模型构建系统全局的覆冰指数指标；综合考虑电网停电风险及系统全局覆冰指数建立输电线路融冰紧迫度指标，动态更新待融冰线路并决策融冰顺序。最后，以IEEE RBTS系统进行算例分析，验证了所提方法的可行性与合理性。     

含电压逆变型分布式电源配电网的短路电流计算

分布式发电接入改变了配电网潮流和短路电流分布，其提供的短路电流将对电网保护和重合闸动作产生影响。文中通过研究电压控制逆变型分布式电源（ⅡDG）的故障响应特性，分析配电网不对称故障时ⅡDG三相平均功率与正负序网功率关系，建立计及电压型ⅡDG对称控制特征的短路计算序分量模型。根据ⅡDG与配电网正负序网络的交互作用，推导电压型ⅡDG的故障电流变化规律，提出计算含电压型ⅡDG配电网短路电流的对称分量迭代算法。在PSCAD/EMTDC仿真软件中建立电压型ⅡDG的电磁暂态模型，仿真验证了该方法的正确性。     

机械通风降温效果的数值评估

地槽通风是机械通风的常用形式,是保证粮食安全储存和保持粮食品质的重要措施.常规的试验研究测量方法难以全面和准确评估设计的有效性和合理性.本研究利用计算机流动模拟的方法(CFD)对常用的U形地槽通风方案进行了数值研究,获得了风道中流速和压力分布的关键性数据,发现了与实际现象相符合的通风死角区域,同时又发现了常规测量手段中难以探测到的风道之间存在的通风薄弱区域,在理论上分析了存在通风死角和风道压力损失的原因.计算流体力学研究方法的运用可成为机械通风优化设计研究的有效工具,为今后机械通风应用技术的发展提供针对性和实用性的依据.     

呼伦贝尔市近30年太阳能资源区划与评估分析

为了客观评估呼伦贝尔市各地太阳能资源潜力，利用海拉尔和富裕2 个辐射观测站1985—2014年辐射观测站的太阳总辐射资料和呼伦贝尔市其他15 个站的日照资料，根据太阳能资源评估方法和标准，计算呼伦贝尔市其他15 个无辐射站的太阳总辐射，分析了呼伦贝尔市太阳总辐射时空分布特征，计算了评估太阳能资源的各种参数。结果表明，呼伦贝尔市太阳能资源储备很丰富或丰富、大部地区稳定或较稳定、可开发利用日数较多，西部和东南部地区尤其适合进行太阳能资源开发利用。     

基于层次分析法的信息安全风险评估要素量化方法

信息安全风险评估是保障信息系统安全的重要基础性工作，但现有风险评估标准和相关研究提供的评估模型和计算方法的评估结果不能有效体现信息系统资产在保密性、完整性、可用性上的不同安全需求和面临的不同风险。利用层次分析法建立风险评估层次分析模型，在借鉴通用脆弱性评分系统指标评价体系基础上改进脆弱性要素量化方法，利用构建的层次分析模型偏量判断矩阵计算“安全事件损失”“安全事件可能性”和“风险值”。通过实验验证，与现有方法相比，所提方法的评估结果能够直观体现资产在保密性、完整性和可用性上面临的不同风险，能为制定风险控制措施提供更加准确、合理的建议。     

数量性状分离分析的精确度及其改善途径

在分析提高数量性分离分析精度的三种途径基础上，对遗传率较低或试验误差较大的数量性状分离分析，综合上述三方法提出了利用P1，F1，P2，B1：2，B2：2和F2：3家系重复试验的联合分离分析法。其基本理 是将分离群体看作由多基因和环境修饰的主基因型正态分布的混合分布。通过油菜初花期的遗传分析表明：分析家系重复试验的家系平均数资料获得的AIC值比分析单一重复资料获得的AIC值更低，P1，F1和P2的加入可增加一阶遗传参数的估计精度；通过方差分析联合估计提供的误差方差可增加二阶遗传参数的估计精度。     

JMPR 农药残留急性膳食摄入量计算方法

农药残留急性膳食风险评估直到最近才引起大家的关注。目前，粮农组织和世界卫生组织农药残留联席会议（JMPR）研究国际范围农药急性膳食风险评估；美国、英国、荷兰、澳大利亚和新西兰也开始进行国家农药急性膳食风险评估。农药急性膳食风险是急性或短期接触毒性与农药急性膳食摄入量的函数。急性膳食接触量评估常用的方法有：定点或确定性方法和概率模型法。在确定性方法中选取食物的大部分人群消耗量和高残留量来计算膳食摄入量，为了解决混合样品中食品个体之间的残留差异，在计算中引入了变异因子。JMPR根据具体情况分为情形1、情形2a、情形2b、情形3来计算农药急性膳食摄入量。中国应该尽快建立健全膳食结构和农产品性状数据库，建立健全市场中农产品的农药残留数据库，并在高毒和中等毒性农药登记前应采用JMPR的确定性方法，进行急性膳食风险评估，提高农药膳食摄入的安全性。     

典型区域土地生态状况精细评估

对土地生态状况进行精细评估可为城乡规划和土地可持续利用提供科学依据。本文以焦作市山阳区为研究对象,基于ArcGIS软件,对山阳区43个行政村单元进行了土地生态状况评估。以土地生态状况自然基础性指标、结构性指标、土地污染退化状况、生态建设与保护综合效应指标及区域性指标5个方面为准则层,选取了10个评估指标、27个元指标构建了山阳区的土地生态状况评估指标体系。采用极差法标准化,熵值法定权重,计算生态状况的综合评估分值,并根据分值大小将山阳区划分为5个区域。结果显示：山阳区生态状况优和良的土地占了总面积的40.5%,主要分布在北部海拔较低,地势平坦的区域;生态状况较差的地区位于北部海拔相对较高的山地丘陵地带,有煤矿开采活动,污染退化现象明显。     

计算机在灰色系统理论中关联分析上的应用

灰色系统理论中的关联分析，在评估农作物新品种时，能对多个相关性状进行定量分析，避免数理统计中的定量分析与定性分析不符，避免要求有大量的样本和典型的概率分布，是目前对新品种进行综合评估较为有效的方法。利用计算机技术，可减少大量的计算工作，提高工作效率；同时，还可依据以前本地的品种区域试验和当地当时的实际表现情况，模拟出当地“理想品种”中各性状的参数和各个性状的不同权重系数，减少人为因素对分析结果的影响程度，提高评估新品种的准确性和可靠性。     

A Static Liquefaction Constitutive Model for Granular Materials Based on the Micromechanical Analysis

Based on the static liquefaction of granular materials, an elastoplastic static liquefaction constitutive model was proposed in the framework of critical state soil mechanics. The yielding surface and hardening rules were obtained by integrating the contact force of the model proposed by Chang and a non-associate flow rule was adopted as well. The model has taken the state dependent dialatency law and the effect of initial density to the stress-strain relationship into consideration. The parameters of the model are simple and have certain physical meanings. The predicted results obtained by the model have a good agreement with the undrained triaxial test of Toyoura sand and sand-silt mixture.     

Texture image retrieval using double density dual tree complex wavelet RH model

For using smooth probability density function to retrieve wavelet coefficient histogram and coefficient module histogram, parameter estimation is complicated, which results in hard to retrieve the texture features effectively. A texture image retrieval method using double density dual tree complex wavelet Refined Histogram(RH) model is proposed. By analyzing the principle of double density dual tree complex wavelet transform (DD-DT CWT) and the inherent relationship between the nonuniform quantizer and RH model, the RH model is extended to retrieve the DD-DT CWT coefficient and the coefficient histogram feature. The RH is used to model the magnitude of the DD-DT CWT. The RH parameters for all magnitude of complex coefficients forms the signature of an image. Image similarity measurement is accomplished by using the Kullback-Leibler divergences . The proposed method combines the advantages of the RH model and the shift-invariant DD-DT CWT. The experiment results show that the proposed methods yields higher retrieval rate than using the General Gaussian Density(GGD) model to fit with the real part or imaginary part of coefficients, and is better than using the Gamma PDF to fit with the magnitude of coefficients.     

Control strategy and parameters optimization outsourcing production inventory system under uncertainty

This paper proposes a control strategy for the optimal control of the outsourcing production inventory system based on production point and production batch. The statistical probability distribution is used to describe the uncertainty of the production capacity of cooperative enterprises and the transportation time. The optimization model of the control parameters is developed with random production capacity for cooperative enterprises and random transportation time in order to minimize the holding cost,setup cost as well as the cost of production capacity waste. A simulation-based control parameters optimization algorithm is designed to solve the proposed model. The control strategy of production inventory system and the control parameters optimization algorithm proposed are validated by an example. We analyze the influence of the variation of the production point and production batch to the performance of the outsourcing production inventory system.     

Calculation of lumped parameter of two-port network forvolume conduction energy transfer

Skin electrode unit is a channel through which energy can be transferred to the implanted device by volume conduction. The unit can be equivalent to lumped circuit, but so far there are no appropriate calculation methods of these circuit parameters, so variable load method based on field-circuit coupled is proposed. A skin electrode unit field circuit coupled model is established to obtain the relationship of the network parameters between voltage and current at electrode port, and the amplitude and phase of the power signal is extracted by the use of all phase FFT spectrum analysis. On this basis, equivalent circuit impedance parameters of the skin electrode unit under various conditions are obtained by the application of variable load method and the validity of the method is verified. As a result, the equivalent circuit impedance parameters obtained in this way can be used for the circuit analysis and optimization of the volume conduction energy transfer system.     

Recognizing the reliability non-coherence components ofdistribution substation typical configuration

Reliability non-coherence components (RNC) may exist in a power system due to the effects of distribution substation connection modes, components reliability performance, load level, and other factors. Recognizing RNCs and removing them from a power system can improve system reliability. The reliability non-coherence phenomenon is analyzed and the reliability non-coherence probability, frequency and energy indices, which can describe the degree of the system reliability non-coherence feature, are proposed. Based on the reliability evaluation theory of substation configuration, recognizing technique of RNCs of distribution substation is proposed. The theoretical analysis and example show that the breaker connects high voltage buses may be the RNC when the rated capacity of one transformer can meet the load requirement, and the reliability parameters of breakers have some effects on the reliability non-coherence features of the typical substation configuration.     

Calculation Method for Equivalent Model of Regular Isolated Structure with Bend shear Deformation

Isolation technique was not only applied for middle or low buildings, but also recently it was applied to high rise buildings. For high rise buildings, multi order vibration should be considered for upper structure isolation and bend deformation should be taken into account in gross deformation because of large height to width ratio. On the basis of previous studies, calculation method of equivalent model for regular isolated structure with bend shear deformation characteristic was proposed according to equivalent criteria after the analysis for some model structures. With the proposed model, handwork calculation of earquake response for isolated structure can be simply completed and design efficiency of isolation structure was improved. Based on the case studies, the equivalency of proposed model was approved.     

A preventive control model for static voltage stability considering the power constraints of weak branches

The voltage instability of power system often occurs when the active power on one or more weak branches exceeds its transfer capability. A preventive control model for static voltage stability is proposed using the active power transfer capability of weak branches as static voltage stability constraints. A local line based voltage stability index is used to determine the critical contingencies, weak branches and transfer capability of each weak branch. A static security analysis method, which is based on DC power flow equations, is used to establish the non linear active power flow expressions on weak branches following each critical contingency. The active power constraints on weak branches can be obtained from the active power flow expressions and transfer capabilities of weak branches. A quadratic optimal model for preventive control including the proposed active power constraints on weak branches is presented. The simulation results for IEEEE14 bus system and IEEE118 bus system demonstrate the correctness and effectiveness of the proposed preventive control model.     

Fatigue Reliability Analysis Based on Probability Density Evolution Method

Based on the probability conservation principle, a joint probability density evolution equation of random parameters and fatigue damage is derived. Probability density evolution surface and cumulative probability isoline of fatigue damage in term of the evolution equation can be used to predict the probability distribution of fatigue damage and fatigue reliability with a given damage threshold. The numerical solution of fatigue reliability for a constant-amplitude test has a good agreement with the experimental result. For a variable-amplitude fatigue test, the computation results, which are calculated according to probability parameters of two constant-amplitude fatigue life tests and Miner's rule, are also in good agreement with the experimental results.     

A NEW METHOD FOR THE STATIC MEASUREMENT AND CALCULATION OF PARAMETERS OF SYNCHRONOUS MACHINES

This paper presents and improved static measurement method for the parameter measurement and calculation of synchronous. By four static-tests of this method all the parameters in the d-axis equivalent circuits of synchronous machines can be determined, and transient and subtransient parameters are calculated. Testing results proves that this method is available in indusirail testing.     

考虑三维地震动作用下振动台试验隔震层简化

基于等效原则、相似理论，考虑三维地震动作用下振动台试验中原型结构隔震层的简化，并对模型结构隔震层进行系统研究。针对不同高宽比隔震结构，提出完全等效简化方法和部分等效简化方法，包括隔震垫等效、模型支座参数及坐标确定、相似关系确定等。利用不同高宽比隔震结构振动台试验，结合有限元数值模拟，进行方法验证。理论推导与数值模拟证明简化方法具有良好的准确性，且在误差允许范围内，简化后的隔震层所获得的加速度、速度、位移等动力特性与简化前相同，可以用于振动台试验模型设计。