基于宏行为的侦察机器人事务执行机制研究

为了便于操作员在侦察现场进行事务规划,提出了基于宏行为的事务描述方法和事务执行机制．按照机器人对环境变化的响应方式的不同,将机器人的行为分成基本行为、组合行为和宏行为,给出了描述这些行为的方法和一个宏行为的设计实例．引入了基于RS模型的行为合成运算符合成机器人行为的方法,从而可以形式化地构建侦察机器人的事务描述．实现了能够解释和执行事务描述的、基于宏行为的事务执行器．仿真和实验结果表明提出的任务描述方法可行,事务执行器能够可靠地完成事务描述所规定的任务．     

基于Pi-演算的Web服务形式化描述模型*

当前对Web服务进行形式化描述的方法多是基于对某个具体Web服务组合规范的抽象,无法兼顾基于全局和局部的设计方法,并且无法描述Web服务组合的体系结构的动态性。本文在对现有的Web服务形式化描述方法进行回顾和总结的基础上,基于Pi-演算建立了Web服务形式化描述模型,将BPEL4WS规范和WS-CDL规范的重要行为在模型中做了映射。最后通过例子说明,基于局部和全局的设计方法在本文提出的模型中的映射是一致的。本文提出的描述模型直接用来进行Web服务组合的设计时,可以更好的描述动态的体系结构。     

Integrating specification of human-computer interface with Jackson system development

Procedures for integrating task analysis and design of the human-computer interface (HCl) with a structured system development method, Jackson system development (JSD), are described. Process structure diagrams (PSDs), the major modelling notation of JSD, described tasks, and task specifications were evaluated for cognitive complexity. Task complexity analysis helped allocation and design of human tasks and to produce computer task support specifications. The cognitive dimension of task analysis highlighted the need for task support actions, especially information display support for working memory. Dialogue specification for a direct manipulation interface design was based on the JSD entity/event model from which the interaction metaphor, screen design, and permissible manipulations were derived. Further PSDs were constructed to specify interface object management processes. Preliminary evaluation of the method was carried out using JSD analysts. Results showed the method proved easy to learn even for non-HCl specialists.     

Some observations on optimal frequency selection in DVFS-based energy consumption minimization

In recent years, the issue of energy consumption in parallel and distributed computing systems has attracted a great deal of attention. In response to this, many energy-aware scheduling algorithms have been developed primarily using the dynamic voltage-frequency scaling (DVFS) capability which has been incorporated into recent commodity processors. Majority of these algorithms involve two passes: schedule generation and slack reclamation. The former pass involves the redistribution of tasks among DVFS-enabled processors based on a given cost function that includes makespan and energy consumption, while the latter pass is typically achieved by executing individual tasks with slacks at a lower processor frequency. In this paper, a new slack reclamation algorithm is proposed by approaching the energy reduction problem from a different angle. Firstly, the problem of task slack reclamation by using combinations of processors’ frequencies is formulated. Secondly, several proofs are provided to show that (1) if the working frequency set of processor is assumed to be continues, the optimal energy will be always achieved by using only one frequency, (2) for real processors with a discrete set of working frequencies, the optimal energy is always achieved by using at most two frequencies, and (3) these two frequencies are adjacent/neighbouring when processor energy consumption is a convex function of frequency. Thirdly, a novel algorithm to find the best combination of frequencies to result the optimal energy is presented. The presented algorithm has been evaluated based on results obtained from experiments with three different sets of task graphs: 3000 randomly generated task graphs, and 600 task graphs for two popular applications (Gauss-Jordan and LU decomposition). The results show the superiority of the proposed algorithm in comparison with other techniques.     

Task reliability assessment in robotic systems

A new method for assessing the performance of a robotic system performing a high-precision task has been developed. The method utilizes an entropy-based formulation to provide a measure of the reliability of a robotic system with respect to a task specification. The derivation of the proposed technique is presented, including two alternative formulations that differ in terms of their complexity and level of approximation. Methods for combining these measures for complex robotic tasks are detailed. The new method is demonstrated in a case study involving a robotic assembly system, in which the entropy formulation is used to select an optimal system design from a set of alternatives. (c) 1995 John Wiley & Sons, Inc.     

Taskmaster: an interactive, graphical environment for task specification, execution and monitoring

Taskmaster is an interactive environment that employs a unique blend of graphic technologies and iconic images to support user task specification. In this environment, problem solving is based on the selection, specification, and composition of tools that correspond to natural sets of ordered operations. The Taskmaster environment is novel in that it

(provides an interactive, visual-based approach to user task specification;

(encourages and supports task specification and refinement processes from both the top-down and bottom-up perspectives; and

(enables one to specify parallel tasks in a natural and convenient manner

To “program” a given task within the Taskmaster environment, one decomposes it into an ordered set of conceptually simple, high-level operations, and then combines (composes) a corresponding network of software tools that implements these operations. Execution of the specified network provides a task solution. Major system components supporting user task specification include a network editor, a tools database and a network execution monitor.     

容错实时任务调度的DSPN建模与分析

复杂系统的形式化描述对新系统的设计以及现有系统的改进与评价都具有十分重要的作用;针对处理机系统容错实时混合任务调度,提出采用确定与随机Petri网进行建模与性能分析;首先,根据任务执行的优先级、周期性、容错性和实时性,将任务分为四类;然后,采用DSPN对任务调度执行过程,不同优先级任务抢占式调度,处理机故障及故障恢复过程进行建模,由此构成处理机系统容错实时任务调度过程的DSPN模型;最后,仿真实验结果表明,在负载相同情况下,处理机利用率基本相同,且具有容错的实时任务调度算法可以有效地降低任务错失率;容错实时任务调度DSPN模型可以为复杂任务调度系统的Petri网建模与分析奠定了基础,并为实际工程应用提供了理论指导。     

数字逻辑实验教学改革探索

针对数字逻辑实验教学存在的问题,提出数字逻辑课程实验教学改革和实验课题设计的思想,改传统的验证性实验为用VHDL语言做设计性实验;介绍实验课题的设计和教学效果。实验课题应该是课程的主要知识点,有合适的难度,无现成的答案。实验课题包括两个组合逻辑设计和3个时序逻辑设计课题,有基本实验,还有选做题目。教学效果表明实验课题的设计是成功的,达到了预期的目的。     

A visual language compiler

The SIL-ICON compiler is a software system for the specification, interpretation, prototyping, and generation of icon-oriented systems. The system design of the SIL-ICON compiler is presented. The icon system G, the icon dictionary ID, the operator dictionary OD, and the extended task action grammar ETAG are described. An application example to design a text editor using the Heidelberg icon set is also presented in detail     

A framework for compliant physical interaction

Although the grasp-task interplay in our daily life is unquestionable, very little research has addressed this problem in robotics. In order to fill the gap between the grasp and the task, we adopt the most successful approaches to grasp and task specification, and extend them with additional elements that allow to define a grasp-task link. We propose a global sensor-based framework for the specification and robust control of physical interaction tasks, where the grasp and the task are jointly considered on the basis of the task frame formalism and the knowledge-based approach to grasping. A physical interaction task planner is also presented, based on the new concept of task-oriented hand preshapes. The planner focuses on manipulation of articulated parts in home environments, and is able to specify automatically all the elements of a physical interaction task required by the proposed framework. Finally, several applications are described, showing the versatility of the proposed approach, and its suitability for the fast implementation of robust physical interaction tasks in very different robotic systems.     

时间分割的池计算网络及其动力学

为解决针对给定任务构建合适的神经元池问题,提出了一种时间分割的神经元池设计方法,该方法将多个子神经元池顺序连接,每两个相邻的子神经元池之间嵌入一个滞后环节以构成时间分割的神经元池,每个子神经元池只需处理一段时间的信息,从而达到复杂记忆任务分解的目的.输出层可对各子神经元池的状态进行整合以获取不同时段的输入特征.对多阶层振荡器的实验表明,在宏观参数相同的情况下,时间分割的池计算网络比常规池计算网络具有更强的记忆能力,能够产生更加多样化的动力学行为.     

任务图模型中实时任务设计

仿真技术的进步推动了实时系统（如核反应堆，军事战场和fly-wire系统）的深入研究，用仿真方法解决实时问题，必须首先给出实时系统描述模型，TCM（task graph model)模型是实时系统描述模型之一，其模型最重要的成员是实时任务，使用量化仿真方法定义了实时任务的4种参数，并细分任务为子任务，此方法更易描述实时应用系统，更易构造TGM的执行模型，其层次化的结构更容易进行研究和软件实现，TGM模型及其任务设计已成功地应用于分布式三星实时侦察仿真系统。     

Beyond performance: Feature awareness in personalized interfaces

Personalized graphical user interfaces have the potential to reduce visual complexity and improve interaction efficiency by tailoring elements such as menus and toolbars to better suit an individual user's needs. When an interface is personalized to make useful features more accessible for a user's current task, however, there may be a negative impact on the user's awareness of the full set of available features, making future tasks more difficult. To assess this tradeoff we introduce awareness as an evaluation metric to be used in conjunction with performance. We then discuss three studies we have conducted, which show that personalized interfaces tradeoff awareness of unused features for performance gains on core tasks. The first two studies, previously published and presented only in summary, demonstrate this tradeoff by measuring awareness using a recognition test of unused features in the interface. The studies also evaluated two different types of personalized interfaces: a layered interfaces approach and an adaptive split menu approach. The third study, presented in full, focuses on adaptive split menus and extends results from the first two studies to show that different levels of awareness also correspond to an impact on performance when users are asked to complete new tasks. Based on all three studies and a survey of related work, we outline a design space of personalized interfaces and present several factors that could affect the tradeoff between core task performance and awareness. Finally, we provide a set of design implications that should be considered for personalized interfaces.