生产单元人机合作策略仿真分析

生产单元不仅要强调先进制造技术,还要重视高素质员工和灵活的人机合作方式,才能适应快速变化的制造环境。为动态、定量地研究生产单元的人机合作策略,结合计算机仿真和Agent建模技术,进行了基于Agent的生产单元人机合作策略仿真研究。建立人机合作仿真模型,提出人机合作仿真的实现方法;研究生产单元指定合作、部分自主合作和完全自主合作的合作机制;并以某发动机生产单元为例,设计了一系列仿真实验,通过比较任务等待时间、订单准时完成率、机器等待率和操作工利用率4个绩效指标,对该生产单元的各种人机分工模式进行了仿真分析和评价,从而指导实际生产单元采取更加合理的分工模式。     

一种网格资源动态分配算法研究

在分布式集群环境中,如何对网格环境中的资源进行有效管理和合理调度至关重要。采用静态固定资源分配等策略不能适应资源和用户请求的动态变化,容易产生资源碎片,造成网格资源利用率低等问题。提出了一种基于分类挖掘的资源动态分配模型和算法,通过资源管理服务器中的守护进程,对集群中的任务动作进行分类挖掘,形成分类规则,用以指导资源的动态分配。实验证明,相比其他分配策略和算法,DRA算法能较好地适应网格环境的变化,具有资源分配利用率高等优点。     

接地网腐蚀诊断优化测量方法

以2个220 kV变电站接地网为模型进行接地网腐蚀诊断模拟试验.在初步诊断节点测量中分别采用大跨距、小分块和大分块结合不动点3种方案,列举出其诊断结果,并对3种方案进行分析、比较.结果表明了选择大分块结合不动点作为初步诊断时测量节点对的优化诊断法,诊断效率最高,效果最好.据此提出了接地网腐蚀诊断初步诊断时的选线原则,使该诊断方法更具工程实用性.     

SPIO标记的反义探针磁学性能检测

采用化学交联法制备超顺磁性氧化铁(SPIO)标记的c-erbB2癌基因反义脱氧寡核苷酸探针,经过1.5T磁共振仪测定,其T2弛豫率为0.156×106mol-1·S-1;振动样品磁强计测定出探针的磁化强度为69.423 8 emu/g Fe,比饱和磁化强度68.413 4 emu/g,比剩余磁化强度为30.354 1 emu/g,剩磁为19.734 5 Gs.为了检测探针的有效性,进一步使用该探针转染高表达c-erbB2癌基因的SK-Br-3肿瘤细胞株,同时使用正义和无义探针转染SK-Br-3肿瘤细胞株、反义探针转染正常小鼠肝细胞作对照,结果发现反义探针能够特异性进入SK-Br-3肿瘤细胞内,且能明显改善该细胞的磁学参数并降低磁共振扫描下的信号强度.     

细胞体系的拓扑构形对钙信号传递的影响

采用细胞内钙动力学模型,考察了在由四个细胞耦合构成的十种可能的构形中,细胞连接的不同构形对噪声诱导的钙信号传递的影响,该噪声施加在其中一个细胞上.研究发现拓扑构形对钙振荡的频率、钙振荡的时间延迟以及钙峰的规整度有着很重要的作用.另外,通过比较网络特性对结果进行了探讨.这些结果表明细胞间的拓扑连接对钙信号的传递有很重要的影响,也有助于理解生物组织体内细胞的合作行为.     

Soluble Jagged 1/Fc chimera protein induces the differentiation and maturation of bone marrow-derived dendritic cells

A soluble Jagged 1/Fc chimera protein （Jagged 1/Fc） was directly used to induce differentiation and maturation of bone marrow-derived dendritic cells （DCs） in mice in vitro. A model of inducing and amplifying DCs in vitrowas established. The effect of Jagged 1/Fc on morphology of DCs induced by both rmGM-CSF and rmlL-4 was observed under a confocal microscope. A fluorescein-labeled monoclonal antibody staining combined with flow cytometry was applied to detect the effect of Jagged 1/Fc on the expression of CD11c, MHC-Ⅱ, CD86, CD80 and CD40 molecules on the surface of DCs. The results showed that Jagged 1/Fc did not affect the morphological properties of DC differentiation induced by both rmGM-CSF and rmlL-4. But it could promote the differentiation and maturation of DCs induced by both. The effect of it was strikingly different in the expression profile of co-stimulating molecules and the morphologic properties of DCs from lipopolysaccharide （LPS）. The levels of MHC-Ⅱ and CD40 molecule expression on the surface of DCs stimulated by Jagged 1/Fc were significantly lower than those stimulated by LPS, and the level of CD80 expression on the surface of DCs induced by Jagged 1/Fc was near to that induced by LPS. Jagged 1/Fc had no influence on the expression of CD86 molecule on the surface of DCs. Jagged 1/Fc when used alone could not maintain the growth, differentiation and maturation of DCs. All the findings indicate that Jagged 1/Fc influences the differentiation and maturation of DCs, which is not markedly similar to LPS, providing important evidence for its development and application as a novel immunosuppressant.     

A model of calcium signaling and degranulation dynamics induced by laser irradiation in mast cells

Recent experiments show that calcium signaling and degranulation dynamics induced by low power laser irradiation in mast cells must rely on extracellular Ca^2＋ influx. An analytical expression of Ca^2＋ flux through TRPV4 cation channel in response to interaction of laser photon energy and extracellular Ca^2＋ is deduced, and a model characterizing dynamics of calcium signaling and degranulation activated by laser irradiation in mast cells is established. The model indicates that the characteristics of calcium signaling and degranulation dynamics are determined by interaction between laser photon energy and Ca^2＋ influx. Extracellular Ca^2＋ concentration is so high that even small photon energy can activate mast cells, thus avoiding the possible injury caused by laser irradiation with shorter wavelengths. The model predicts that there exists a narrow parameter domain of photon energy and extracellular Ca^2＋ concentration of which results in cytosolic Ca^2＋ limit cycle oscillations, and shows that PKC activity is in direct proportion to the frequency of Ca^2＋ oscillations. With the model it is found that sustained and stable maximum plateau of cytosolic Ca^2＋ concentration can get optimal degranulation rate. Furthermore, the idea of introducing the realistic physical energy into model is applicable to modeling other physical signal transduction systems.     

Differentiation of human embryonic stem cells along a hepatocyte lineage and its application in liver regeneration

Hepatocyte transplantation and bioarUficial liver （BAL） as alternatives to liver transplantation offer the possibility of effective treatment for many inherited and acquired hepatic disorders. Unfortunately, the limited availability of donated livers and the variability of their derived hepatocytes make it difficult to obtain enough viable human hepatocytes for the hepatocyte-based therapies. Embryonic stem cells （ESCs）, which could be isolated directly from the blastocyst inner cell mass, have permanent self-renewal capability and developmental pluripotency and therefore might be an ideal cell source in the treatment of hepatic discords. However, differentiation of hESCs into hepatocytes with significant numbers remains a challenge. This review updates our current understanding of differentiation of ESCs into hepatic lineage cells, their future therapeutic uses and problems in liver regeneration.     

动态称重系统的试验数据采集与处理方法

本文首先简要地介绍一下数据采集前端的信号调试电路的模拟信号处理,然后叙述了动态称重信号的特点,紧接着介绍基于删的称重数字信号采集,再着重介绍数据滤波以及系统试验方案,最后给出了整个系统的程序设计方案。     

三维聚合物电解质膜燃料电池中水的输运模拟

针对新型螺旋形加压聚合物电解质膜燃料电池,提出了一种液态水生成和输运效应的数值模型.该数值模型基于燃料电池的物理机理、流体流动、传热导、多孔介质中的传质、电化学反应、含相变的多相流动、电流输运、多孔介质和固体导电区域中的位势场以及穿过聚合物膜的水的输运设计优化过程.在分析中还使用了燃料电池模型.例如,电化学模型--用于预测局部电流密度和电压分布;位势场模型--用于预测多孔介质以及固体导电区中的电流和电压;多相混合物模型--用于预测在多孔扩散层中的液态水和气体流;薄膜多相模型--用于研究气体流道中的液态水流.最后给出了聚合物电解质膜燃料电池液态水生成和输运的理论模型的数值结果,包括催化层和膜中的H2,O2和H2O的质量和克分子数的等值线图.