复杂系统人机交互中的多任务调度策略综述

目的 随着自动化技术的不断发展,系统的复杂性导致多任务成为人机系统交互中常见的场景,多任务呈现出信息模态的复杂化、任务类型多样化、任务中断普遍化等特点,其中多任务的调度策略对系统的运营安全和绩效起着十分重要作用.通过梳理和总结复杂系统人机交互中的多任务调度策略,旨在解决复杂人机系统在设计、建造、维护过程中的问题.方法 通过对国内外相关文献的回顾,以认知心理学的双任务转换生理机制实验研究为起点,从任务调度策略研究逐步分析延展到中断管理和多任务调度决策的发展过程,着重围绕人机交互过程中的多任务调度行为和任务突显性、优先级、参与感、难度、执行时间等不同属性对任务调度决策的影响,进行了详细梳理和总结.结论 在研究综述和相关文献的基础上指出了既有任务调度策略研究中存在的局限性,并从系统交互设计的角度对将来的人机交互多任务管理研究提出了建议.     

Symmetric collocation BEM/FEM coupling procedure for 2-D dynamic structural–acoustic interaction problems

 This paper presents a symmetric collocation BEM (SCBEM)/FEM coupling procedure applicable to 2-D time domain structural–acoustic interaction problems. The use of symmetry for BEM not only saves memory storage but also enables the employment of efficient symmetric equation solvers, especially for BEM/FEM coupling procedure. Compared with symmetric Galerkin BEM (SGBEM) where double boundary integration should be carried out, SCBEM can reduce significantly the computing cost. Two numerical examples are included to illustrate the effectiveness and accuracy of the proposed method. Received: 2 November 2001 / Accepted: 27 May 2002     

应用SIMOGRAMS方法解决装配生产线瓶颈

详细介绍了SIMOGRAMS,一种新的人机操作分析、联合操作分析的新方法.针对某轮胎公司现有生产能力无法满足市场需求的实际问题,首先确定瓶颈车间-成型车间,然后运用SIMOGRAMS工具,从该车间装配生产的主要产品装配流程入手,对整个装配过程进行联合操作分析,提出了初步改善方案并分析改善效果.最后将装配线从固定式布置改变为产品式布置,根据各基本工作单元所包含的工作量将其组合成工作量基本相等的工作包,并将这些工作包分派给每个操作者或工作站,形成基于几种产品的细胞单元,大幅度提高了手工装配线的生产能力和灵活性.     

A case for information theory-based modelling of human multitasking performance

Technological advances have led to increased prevalence of human multitasking. Traditionally, multitasking performance is measured for each individual task, utilising multiple performance metrics. Recently, the human operator informatic model (HOIM) has been developed as a quantitative model of human–machine interaction capable of measuring multitasking performance with a single metric. In this study, we investigated the performance effects of both a different number of tasks and five different task combinations while maintaining a constant level of overall difficulty. Results indicate that, at a constant difficulty level, neither number of tasks nor task combination significantly affects multitasking performance, indicating the reliability of input baud rate as a measure of system complexity. No task interaction effects were found among the different tasks. This study demonstrates the application of information theory for modelling of human multitasking performance and makes a case for the use of the HOIM in future studies of human information processing.     

单输入多输出耦合设计任务二阶段迭代模型研究

产品开发过程中单输入多输出耦合设计任务间存在复杂的信息依赖关系。采用单阶段方法的任务执行方式时,因所执行的任务数量多并且需传递的信息量大,致使任务间存在的复杂信息关系难以被理清,从而导致任务执行过程中的方案分配不够合理,任务间的迭代返工次数过多,产品开发周期过长。针对这些问题,在深入分析单输入多输出耦合设计任务单阶段迭代模型的基础上,提出了一种任务迭代过程中的信息处理策略,并构建了一种单输入多输出耦合设计任务的二阶段迭代模型及其求解执行时间的数学模型。应用该数学模型,可以计算得到最佳二阶段设计任务分配方案。以某发动机开发项目为例,进行了该方法的应用分析。研究表明,采取二阶段迭代模型,任务迭代执行时间比单阶段短,并且通过合理分配在1,2两个阶段执行的任务,能够获得最短的二阶段任务迭代执行时间。该方法根据任务间不同的信息关系选择合适的任务迭代模型,能够有效缩短产品开发周期,可为产品设计人员在产品开发过程中选择合理的任务执行方式提供一定的理论参考。     

Alternatives and challenges in optimizing industrial safety using genetic algorithms

Safety (S) improvement of industrial installations leans on the optimal allocation of designs that use more reliable equipment and testing and maintenance activities to assure a high level of reliability, availability and maintainability (RAM) for their safety-related systems. However, this also requires assigning a certain amount of resources (C) that are usually limited. Therefore, the decision-maker in this context faces in general a multiple-objective optimization problem (MOP) based on RAMS+C criteria where the parameters of design, testing and maintenance act as decision variables. Solutions to the MOP can be obtained by solving the problem directly, or by transforming it into several single-objective problems. A general framework for such MOP based on RAMS+C criteria is proposed in this paper. Then, problem formulation and fundamentals of two major groups of resolution alternatives are presented. Next, both alternatives are implemented in this paper using genetic algorithms (GAs), named single-objective GA and multi-objective GA, respectively, which are then used in the case of application to solve the problem of testing and maintenance optimization based on unavailability and cost criteria. The results show the capabilities and limitations of both approaches. Based on them, future challenges are identified in this field and guidelines provided for further research.     

Adhesion force during microcontact interaction between cylindrical-segment-on-flat and flat bodies

Adhesion force including its both attractive and repulsive components during microcontact interaction between cylindrical-segment-on-flat and flat bodies is formulated using the volumetric integration of interactions among the atoms. Thenceforth the corresponding formulation for cylinder-on-flat and flat-on-flat is developed and compared with the available counterpart attractive force and they are in excellent agreement with each other. However, the present study provides also the repulsive component of adhesion force for these contact geometries. The formulation is also extended for a cylindrical segment with two radii to model the elastic–plastic deformation. Several phenomena related to adhesion during microcontact are then studied leading to the following salient observations. The adhesion force during microcontact interaction can be of the same order as the applied force, and thus causes the plastic deformation. The attractive force from the cylindrical segment is the major component of adhesion force for its radius/height ratios smaller than 1000 while that from the bulk body is the major for the larger ratios, i.e. when the cylindrical segment is similar to an asperity. There is considerable difference in the attractive force between a cylinder and a cylindrical-segment-on-flat for the smaller values of radius. The difference between attractive and total adhesion force is significant (∼60%) when adhesion force is the maximum, but it rapidly decreases with increasing separation distance and can be neglected at the separation distance larger than the twice of inter-atomic equilibrium distance. The equilibrium separation distance is about 60% of the inter-atomic equilibrium distance and adhesion force is maximum at about 80% of the inter-atomic equilibrium separation distance for both deformed and undeformed configurations. The adhesion force also increased with the deformation of cylindrical segment. The views expressed in this article are those of the authors and do not reflect the official policy or position of the United State Air Force, Department of Defense, or the U.S. Government.     

A new model for the analysis of composite steel – concrete slab and beam structures with deformable connection

 In this paper a solution to the bending problem of reinforced concrete slabs stiffened by steel beams with deformable connection including creep and shrinkage effect is presented. The adopted model takes into account the resulting inplane forces and deformations of the plate as well as the axial forces and deformations of the beam, due to combined response of the system. The analysis consists in isolating the beams from the plate by sections parallel to the lower outer surface of the plate. The forces at the interface producing lateral deflection and inplane deformation to the plate and lateral deflection and axial deformation to the beams are related with the interface slip through the shear connector stiffness. Any distribution of connectors along the interface and any linear or non-linear load–slip relationship or partial shear connection for the shear connectors can be handled. The creep and shrinkage effect relative with the time of the casting and the time of the loading of the plate is taken into account. The solution of the arising plate and beam problems, which are nonlinearly coupled, is achieved using the analog equation method (AEM). The adopted model compared with those ignoring the inplane forces and deformations, approaches more reliable the actual response of the plate–beams system. Moreover, it permits the evaluation of the shear forces at the interfaces, the knowledge of which is very important in the design of composite steel–concrete structures. Received: 21 June 2002 / Accepted: 5 March 2003     

模具企业生产调度管理系统的研究

为适应模具企业新的生产方式,本文提出了一种结合合同网协议、GPGP协同机制和TAEMS任务描述语言的任务分配和调度方法,并建立层/级结构的整体框架和各级调度策略.该方法从整体的角度分析问题,提高了调度结果的一致性和优化性.初步的验证表明该方法是有效的.     

群桩(土)-承台-结构的动力相互作用分析

基于共同作用理论,在导出了时域中上、下部相互作用动力平衡方程的基础上,利用桩-桩动力相互作用因子法获取了群桩的动力阻抗,对水平地震作用下群桩-土-上部结构的反应特性进行了较全面的分析.着重讨论并估计了群桩抽桩布置于体系动力反应的影响,通过数值计算分析,取得了一些有价值的认识,并认为受水平地震力作用桩承结构也可借鉴考虑竖向上、下部共同作用沉降优化的理念和思想来进行抽桩设计.     

ZnS:Sm and ZnS:Cu,Sm electroluminescent phosphors

Electroluminescent ZnS: Sm and ZnS: Cu, Sm phosphors have been prepared and their electroluminescent (el) characteristics have been studied. The time-averagedel brightness follows the Alfrey-Taylor relation over a wide range of frequencies. The constants of this relation have been determined. Theel emission shows one main and one auxiliary peak during each half cycle of the applied voltage. Variation of current with applied voltage has also been investigated.