Relating the power of the Multiple Associative Computing (MASC) model to that of reconfigurable bus-based models

The MASC (Multiple ASsociative Computing) model is a multi-SIMD model that uses control parallelism to coordinate the interaction of data parallel threads and supports associative SIMD computing on each of its threads. There have been a wide range of algorithms developed for this model. Research on using this model in real-time system applications and building a scalable MASC architecture is currently quite active. In this paper, we present simulations between MASC and reconfigurable bus-based models, e.g., various versions of the Reconfigurable Multiple Bus Machine (RMBM). Constant time simulations of the basic RMBM by MASC and vice versa are obtained. Simulations of the segmenting RMBM, fusing RMBM, and extended RMBM by MASC in non-constant time are also discussed. By taking advantage of previously established relationships between RMBM and two other popular parallel computational models, namely, the Reconfigurable Mesh (RM) and the Parallel Random Access Machine (PRAM), we extend our simulation results to further categorize the power of the MASC model in relation to RM and PRAM.     

Integrated simulation framework for the process planning of ships and offshore structures

Recently, requests for accurate process planning using simulation have been increasing in many engineering fields, including the shipbuilding industry. To date, designers of shipyards have developed in-house simulation systems or used commercial systems such as the QUEST by Dassault system when requests for the simulation of process planning have occurred. However, these methods have some limitations. First, it requires a lot of time to develop a new in-house simulation system. In addition, it is hard to reuse previously developed systems when developing a new one and it is also hard for these to satisfy the various needs of shipyards effectively.     

Quasi-Monte Carlo methods for Markov chains with continuous multi-dimensional state space

We describe a quasi-Monte Carlo method for the simulation of discrete time Markov chains with continuous multi-dimensional state space. The method simulates copies of the chain in parallel. At each step the copies are reordered according to their successive coordinates. We prove the convergence of the method when the number of copies increases. We illustrate the method with numerical examples where the simulation accuracy is improved by large factors compared with Monte Carlo simulation.     

A modelling framework to support farmers in designing agricultural production systems

Given the new challenges confronting world agriculture, innovative production systems need to be designed at the farm level. As experiments are not easy to conduct at this level, modelling is required to evaluate ex-ante the multiple impacts of proposed innovations. A conceptual framework based on three sub-systems (biophysical, technical, and decisional) interacting within the farm is proposed to guide this process. The advantages and limitations of the framework are illustrated with three examples. The first describes a conceptual, rule-based model representing management decisions for the cultivation of salad in southern France. The second uses a computerized model of the three sub-systems to study irrigation management strategies on farms producing hay in southern France. The third presents a spreadsheet model designed to assist dairy farms in Morocco to define new livestock and forage system strategies. The lessons learned concern the modelling process, the fit between the type of model and its use, and the advantage of involving stakeholders in the design process of tools and innovations.     

设计引导合理健康的生活方式

设计,虽然不是生产力,它不能决定社会、经济、甚至生态环境的发展,但是它的本质特征所表现出的那种协调性,却起到了很大的引导作用,在人类共同的大课题面前,只有设计能担负起"创造更合理,更健康的生活方式"的历史使命。     

差压测漏仪微泄漏的建模与仿真

为研究密封件的微泄漏量大小与检测时间之间的关系,实现检测时间与检测可靠性的优化,通过分析密封件微小泄漏的理论,建立了微小泄漏的等效模型。基于此模型,采用AMESim仿真软件对差压测漏仪检测微小泄漏的动态特征进行仿真分析,得出了被测件微小泄漏时的动态P-T关系曲线。结果表明,此仿真试验能反映出密封件微泄漏时压力与时间的动态关系,为制定最优的检测时间提供了依据。     

A simulation-based scheduling system for real-time optimization and decision making support

This paper presents an industrial application of simulation-based optimization (SBO) in the scheduling and real-time rescheduling of a complex machining line in an automotive manufacturer in Sweden. Apart from generating schedules that are robust and adaptive, the scheduler must be able to carry out rescheduling in real time in order to cope with the system uncertainty effectively. A real-time scheduling system is therefore needed to support not only the work of the production planner but also the operators on the shop floor by re-generating feasible schedules when required. This paper describes such a real-time scheduling system, which is in essence a SBO system integrated with the shop floor database system. The scheduling system, called OPTIMISE scheduling system (OSS), uses real-time data from the production line and sends back expert suggestions directly to the operators through Personal Digital Assistants (PDAs). The user interface helps in generating new schedules and enables the users to easily monitor the production progress through visualization of production status and allows them to forecast and display target performance measures. Initial results from this industrial application have shown that such a novel scheduling system can help both in improving the line throughput efficiently and simultaneously supporting real-time decision making.     

Enhancing graph production skills via programmed instruction: An experimental analysis of the effect of guided-practice on data-based graph production

A computer-based graphing simulator used tutorial modules to teach 61 undergraduate college students how to create cumulative graphs from sets of data. One group was required to complete the steps of constructing an appropriate graph within a computer-provided graphical workspace, while the other group did not have graphic construction requirements during the tutorial, but could optionally construct the graph within the workspace. Following the tutorial instruction, each student was given three blank sheets of graph paper, a pencil, two sets of data, and the requirement of physically constructing graphs based on the given data. Students who were required to actively complete graph construction steps during their tutorial subsequently produced graphs from the new data that were significantly better than those students who had the option of practicing in the workspace. Results suggest that the presence of response contingencies within the graphical workspace increases subsequent graph construction performance. The efficiencies possible with electronic instruction are discussed.