PC/104总线工控机及其在饲料配料控制中的应用

通过一个应用实例来说明ＰＣ／１０４总线工控机不仅在结构、硬件、软件上与标准ＰＣ总线工控机完全兼容，而且由于采用模块化设计方法使之体积更紧凑、可靠性更高、功耗更低。     

我国企业保险体系的若干问题探析

本文总结并分析了我国企业保险体系中存在的若干问题，并结合我国经济体制改革的新形势，提出了如何解决这些问题，完善企业保险工作的构想。     

考虑风电接入和气电转换的综合能源系统日前区间优化

针对气电综合能源系统优化调度中未充分挖掘可调度因素、未充分考虑风电预测误差不确定性的现状,研究含风电的气电综合能源系统日前区间优化调度方法。首先,基于区间数学对风电出力的不确定性进行区间描述,综合考虑抽水蓄能、气电双向转换以及需求响应等资源和技术,并用区间数学表示优化目标和优化约束,构建含高比例风电的气电综合能源系统日前优化模型,综合优化系统的经济性、环保性。然后,基于区间序关系和可能度的方法将区间优化模型转化为确定性优化模型,继而采用Jaya算法进行求解,保证求解的高效性和解空间的可行性。最后,进行算例分析,仿真结果验证了综合利用抽水蓄能、气电双向转换以及需求响应等要素对系统进行区间优化,能取得优化效果上的优势,并能为系统调度人员提供风电不确定度对系统优化影响的信息。     

某星载大口径天线子系统的力学仿真分析

星载天线在发射及在轨阶段将面临严酷的力学环境,要求具有极高的可靠性。为了验证其刚度和强度,缩短研发周期,文中采用NX Nastran软件建立了某星载大口径天线子系统的力学仿真模型;为了验证仿真的有效性,进行了该天线子系统的模态测试,经对比发现两者数据一致性较好;基于建立的有限元模型,分析了该天线子系统在正弦振动和热循环环境工况下的结构响应和受力情况,得到了相应的加速度、位移和应力云图。结果表明,该天线子系统的结构刚强度均满足星载环境要求。该仿真分析对星载天线子系统的结构设计具有重要的指导意义。     

点雨量和面雨量的最优估计

降雨量系随空间位置变化的一种区域化变量,既有随机性,又有一定的结构性。本文应用克里格法对点雨量和面雨量进行了最优估计。由该法得到的估计值符合无偏性,且估计方差最小,因此它比传统常规方法具有较高的可靠性。     

Stress and deformation analysis on deep surrounding rock at different time stages and its application

Based on the characteristics of the deep circular tunnel, the surrounding rock was divided into three regions: the cracked region, the plastic region and the viscoelastic region. The process of rock stress deformation and change was divided into three stages after the roadway excavation. By using the elastic–plastic mechanics theory, the analytical solutions of the surrounding stress and displacement at different stages and the radii of cracked and plastic regions were formulated. We additionally explained the surrounding rock stress and displacement which appeared in practical project. Simultaneously, based on the problem which emerged from a mine in Xuzhou during the excavating process of rock roadway’s transport, we got the theoretical solutions for the stress and displacement in the process of rock roadway’s excavation and considered that the broken area of rock roadway was largely loosing circle. The results indicate that according to the rheological characteristics of surrounding rock, in the primeval excavation of rock roadway, we should increase the length of anchor bolt and cooperate it with anchor nets cable-U steel supporting frame. In addition, when the deformation rate of the surrounding rock is descending after the 15 days’ excavation, we should use the “three anchor” supporting method (anchor bolt spray, anchor note and anchor rope) and set aside about 20 cm as the reserved deformation layer.     

化工冶金学家陈家镛

1958年中国科学院化工冶金研究所(现过程工程研究所)的创建,与建国初期的国家经济发展和国防建设的需求紧密相关。1956年陈家镛受到世界著名冶金学家叶渚沛的邀请,到正在筹建中的化工冶金研究所工作。作为国内该领域开拓者和学术带头人,陈家镛院士的学术经历是本文主线。以他带领同事们开展湿法冶金研究为案例,分析了国家重大战略需求与科学技术研究之间的关系。重点介绍了他在冶金、化工、材料等研究领域做出的重要学术贡献,以及将代表性科研成果经过中间试验应用于实际生产、解决企业所面临的技术难题的情况。藉此反映了以过程工程研究所为代表的国立科研机构,围绕国家重大战略需求开展科技攻坚的历程与成果。     

山东省某测井公司放射工作人员职业健康状况分析

分析了山东省某测井公司放射工作人员职业健康检查结果。结果表明:(1)放射工作人员的血压异常率与年龄、工龄有关,随着年龄、工龄的增加而增高,差异显著;(2)不同年龄段间比较,肾功能异常率差异显著;(3)不同工龄段间比较,胸部X射线摄影异常率差异显著。结论认为,从事测井工作的放射工作人员长期接触低剂量辐射,应提高防护意识,...     

Analysing the shielding effect of a concrete wall reinforced with steel plate using generalised surface integral equations

The electromagnetic shielding effect of a two-dimensional concrete wall reinforced with steel plate is analysed using a generalised surface integral equation (GSIE) method developed from Huygens? equivalence principle. The wall is divided into small blocks. Each block is analysed independently at first, and its electromagnetic characteristics are expressed by an associated generalised transition matrix defined on the reference surface of that block. In order to find the electromagnetic characteristics of the whole system, a GSIE formulation is established on the reference surface of all blocks, which can be solved efficiently using characteristic basis functions.     

Studied on a novel human keratinocyte membrane delivery system in vitro

The culture of keratinocytes on flexible membranes has been proposed as a means to simplify, accelerate and improve the efficiency with which proliferating cells are delivered to full thickness or non-healing skin defects. The purpose of this article was to study the ability of chitosan-gelatin manbranes to facilitate the growth of human keratinocytes. The membranes with different chitosan contents were studied. The surface properties of chitosan-gelatin membranes were investigate by SEM, and water contact angle test. The mechanical property of the membranes was tested. Data implied that gelatin could make the membranes more flexible and hydrophilic than chitosan membranes, which may regulate the seeded cells behavior. Loading human keratinocytes on chitosan-gelatin membranes, cells attachment, spread, and growth were investigated by light microscopy, SEM, and MTT test. The results suggested that the adhesion and proliferation of keratinocytes seeded on chitosan-gelatin membranes were same as on tissue culture plate, in which gelatin could modify the interaction between keratinocytes and chitosan membranes. Therefore, chitosan-gelatin membrane is a good candidate for keratinocytes delivery system.