小子样下基于Bayes推广理论的单桩竖向承载力研究

为了更有效地确定小子样下单桩承载力的设计值,利用勘探阶段的静力触探资料,结合《建筑桩基技术规范》中的经验参数法,先使用Grubbs方法剔除基桩参数数据中的疏失误差数据, 得到单桩竖向承载力的验前信息,然后根据静载荷试验结果对先验信息进行调整,得到关于单桩竖向承载力的验后信息。经比较分析,利用Bayes方法估算的单桩极限承载力更加精确,置信区间更加集中,从而为小子样条件下单桩竖向承载力设计值提供了理论参考依据。     

高强钢焊接接头扩散氢行为研究

针对900 MPa钢级高强钢,采用甘油法测试焊接接头中扩散氢含量,并研究焊后放置72 h内扩散氢的逸出规律.研究结果表明,试板装瓶后0.5～12 h时,扩散氢的逸出速度很快,逸出量比较大,可以达到总逸出量的90％;在12～24 h这一时间区间内,扩散氢逸出速度变慢;在24～72 h时间内,扩散氢逸出量基本维持不变.由此看出,在焊接后24 h内,熔敷金属中的扩散氢已经逸出怠尽.本研究结果也表明对高强钢焊接结构进行消氢处理时必须在焊后尽快进行,否则消氢处理的意义不大.     

Significance of Covariance Matrices in Nuclear Data Evaluation

Tritium decontamination using ultra violet (UV) lamp and laser was performed. Simulated co-deposited layer on tungsten substrate was deposited by C₂H₂ or C₂D₂ glow discharge. The co-deposited layer was irradiated to UV lights from a xenon excimer lamp (172 nm) or ArF excimer laser (193 nm) and the in-situ decontamination behavior was evaluated by a mass spectrometer. After the UV irradiation, the hydrogen concentration in the co-deposited layer was evaluated by elastic recoil detection analysis (ERDA) and the depth profile was analyzed by secondary ion mass spectrometry (SIMS).

For the co-deposited layer formed by C₂D₂ glow discharge, it was found that M/e 3 (HD) gas was released mainly during the UV lamp irradiation while both M/e 3 (HD) and M/e 4 (D₂) gases were detected during the UV laser irradiation. Though the co-deposited layer was not removed by UV lamp irradiation, almost all the co-deposited layer was removed by UV laser irradiation within 1 min. The ratio of hydrogen against carbon in the co-deposited layer was estimated to be 0.53 by ERDA and the number of photon needed for removing 1 fim thick co-deposited layer was calculated to be 3.7×10¹⁸ cm^-2 for the UV laser by SIMS measurement. It is concluded that C-H (C-D) bond on the co-deposited layer were dissociated by irradiation of UV lamp while the co-deposited layer itself was removed by the UV laser irradiation.     

Project network-oriented materials management policy for complex projects: a Fuzzy Set Theoretic approach

This work devises a materials management policy integrated with project network characteristics of complex projects. It proposes a relative quantitative measure, overall criticality (OC), for prioritisation of items based on penalty incurred due to their non-availability. In complex projects, practicing managers find it difficult to measure OC of items because of the subjective factors and intractable nature of penalties involved. However, using their experience, they can linguistically identify the antecedents and relate them to consequent OC. This work adopts Fuzzy Set Theory to capture managerial tacit knowledge which provides them enough flexibility to provide information in real form. Computed OC values can be used for items prioritisation and as shortage cost coefficient in inventory models. The revised materials management policy was applied to a shipbuilding project. OC values were analysed to justify the importance of incorporating project network characteristics and potential cost savings were calculated.     

化工企业安全网格化管理的思考与实践

化工企业安全网格化管理是一种数字化企业管理新模式,代表了现代企业管理的新方向;分析了企业安全网格化管理模式的缘起,阐述了其基本理念和方法,并以上海焦化有限公司的具体实践为例说明了其创新之处,最后以调查数据为支撑着重研究了其效用和价值。     

Bauxite Based Refractory Bricks for Hot Blast Stove YB/T 5016-2000

1Scope This standard specifies the technical requirements, test method, inspection rules, packing, marking, transportation, storage and quality certificate of bauxite based refractory bricks for hot blast stove.     

阀门产品出厂检验与型式试验标准规定的分析

论述了阀门检验规则与产品合格的关系。从阀门产品标准规定的检验规则入手,指出了现行标准出厂检验与型式试验规定中存在的问题。给出了阀门产品检验时根据抽样检验控制理论和科学制定验收检验规则的检验方案。     

基于DBR—GA的混合流水车间调度方法

针对带有并行机与批处理机的混合流水车间调度问题,提出一种基于“鼓-缓冲器-绳子”一遗传算法的调度方法。首先建立了识别瓶颈工作站的步骤,开发了相应的启发式算法,进行了问题初始解的求解,在此基础上应用改进遗传算法对作业在瓶颈工作站上的加工顺序进行优化,并利用缓冲机制决定了作业的投放策略,同时对非瓶颈设备运用优先级规则进行了作业的排程。最后通过算例实验和性能分析,验证了所提调度方法的有效性与实用性。     

粮油食品物流敏捷配送优化技术的研究

在目前国内外现有的研究中,迫切需要从理论与实践层面研究归纳或提炼出实用的知识准则,以此作为基础以提高粮油食品物流的配送能力。论文提出了支撑粮油食品物流敏捷配送方案快速生成和快速求解的7大知识准则,研究了粮油食品单品种货物和多品种货物敏捷配送优化两大问题。通过将这两大问题分解成4个不同的优化子问题,并建立了4个通用的模型及求解算法。算例分析结果表明,利用本研究的算法,无论是针对粮油食品单品种还是多品种货物对象,在不同的车辆吨位序列下,配送优化后的空载率均较低,货物周转量也较低,取得了良好的装载效果。