Review and reappraisal of modelling and predicting mental workload in single- and multi-task environments

The concept of mental workload has long been recognized as an important factor in individual performance within complex systems. It is documented that either overload or underload may degrade performance, and further affect the efficiency of the whole system. Therefore, systems designers need some explicit models to predict the mental workload imposed on individuals by the system at an early design phase so that alternative system designs can be evaluated. In examining mental-workload literature, it is found that few predictive mental-workload models have considered factors specific to individuals. This research aims to develop a practical framework for predicting mental workload in both single- and multi-task environments considering such individual factors. In order to describe mental workload more precisely and more completely, a framework for mentalworkload definitions, which contains instantaneous workload, average workload, accumulated workload, peak workload and overall workload, is proposed. In order to model individual factors, two new variables, i.e. effective workload and ineffective workload, are introduced to model the taskgenerated workload and individual-generated workload. The extension of the model to multi-task environments is also discussed. The proposed conceptual models are domain-independent and could be used to guide the development of operational models for different specific tasks.     

An Examination of Procedural and Object-oriented Systems Analysis Methods: Does Prior Experience Help or Hinder Performance?*

Interest in object-oriented analysis (OOA) and object-oriented design (OOD) has expanded rapidly over the last several years. Proponents of OOA and OOD have called the shift to these methods “revolutionary” and have cited a number of impressive claims with respect to their use. However, empirical research investigating these claims remains in its infancy. Moreover, an examination of the literature reveals inconclusive and often conflicting results for OOA and OOD methods relative to traditional data and/or procedural techniques. This paper presents the results of an empirical study that examined both experienced and novice systems analysts using both procedural and object-oriented techniques. This research examined whether experience in using procedural methods helped or hindered performance using OOA and compared procedural and OOA methods on the subjective mental workload induced. A human problem-solving model adopted from Newell and Simon (1972) provided the theoretical framework for this study. Dependent variables include subjective mental workload, solution quality, time to perform task, and attitudinal measures. Although some of these dependent variables have been used in past research, we believe this is the first time that subjective mental workload (SMW) has been examined in an IS context. Our results indicate that both novice and experienced subjects demonstrate higher SMW when using OOA. In addition, as a group, novices prefer object-oriented techniques and find these techniques easier as compared to experienced subjects.     

Operator performance and subjective response in control of flexible manufacturing systems

Abstract

In this study, allocation of functions and system size (number of machines) were manipulated to test their effects on operator performance and subjective response in a flexible manufacturing system (FMS). An experiment was conducted using a cross-over design with three independent variables: number of machines, task allocation, and sequence of task presentation. Operator performance was measured by response time, and subjective response assessed using two questionnaires. Physiological measures were also taken (EKG and respiratory rate). The results revealed that the number of machines in the system did not affect performance or subjective or physiological response while the effect of allocation level was significant for both performance and subjective response.     

考虑第三方物流竞争的第四方物流运输与库存外包决策

第四方物流在物流外包中的主导地位和第三方物流在提供服务时基于配送频率的竞争对物流外包产生重要影响。针对这一问题,本文建立基于价格、配送频率和需求分配比例的三阶段非合作动态决策模型和库存运输联合优化模型(ITIO)来分析4PL主导的业务外包和3PL之间的竞争,通过对比两个模型来分析决策权对个体和系统绩效的影响,并用算例验证了文章的结论。研究表明,在3PL同质且需求分配比例为0.5时,三阶段非合作动态决策模型的配送频率比ITIO最优值小29%,库存持有成本比ITIO最优值高41%,物流配送成本比ITIO最优值小21%,总成本比ITIO最优值大9%。库存运输联合优化模型虽然具有一定成本优势,但是其过分强调协调不利于3PL之间的竞争和提高。     

Operator performance and subjective response in control of flexible manufacturing systems

In this study, allocation of functions and system size (number of machines) were manipulated to test their effects on operator performance and subjective response in a flexible manufacturing system (FMS). An experiment was conducted using a cross-over design with three independent variables: number of machines, task allocation, and sequence of task presentation. Operator performance was measured by response time, and subjective response assessed using two questionnaires. Physiological measures were also taken (EKG and respiratory rate). The results revealed that the number of machines in the system did not affect performance or subjective or physiological response while the effect of allocation level was significant for both performance and subjective response.     

Intra-Organizational and inter-organizational resource allocation in two-stage network systems

There are organizational systems, such as bank branches and two-stage supply chains, which are composed of multiple parallel two-stage structures. Resource allocation in these systems is to maximize the benefit of the overall organization from a global viewpoint. In this study, we consider two types of systems at an organizational level: a centralized organizational system treating the whole two-stage production process as a basic unit, and a decentralized organizational system including two sub-organizations (groups) treating one of the two-stage production processes as a basic unit. We propose intra-organizational and inter-organizational resource allocation plans for two different organizational systems, respectively. Specially, two modes of free intermediate resource allocation (Free IRA) and fixed intermediate resource allocation (Fixed IRA) are discussed for the decentralized organizational system. The proposed allocation plans are based on two-stage data envelopment analysis models with bi-level formulations, in which the upper-level model is to maximize the entire organizational effectiveness (total outputs minus total inputs) by determining the optimized input resources and output targets while the lower-level model is concerned with efficiency constraints of all decision-making units simultaneously. The developed methods are illustrated by an application to a real-world problem with 17 city bank branches.     

A Simulation of Partial Information Use in Decision Making: Implications for DSS Design

Information matrices are often the output produced by a decision support system. These matrices are a common method for expressing a decision situation under different decision-making scenarios. The decisions involved in designing a decision support system to generate the information matrix are important and involve several cost and benefit components. A designer needs guidance in making effective design decisions in this context. Such guidance can be provided by considering the relationships among specific design decisions, costs, and benefits. The general objective of this study is to provide a comprehensive framework for this purpose. This study is the first to develop and present a comprehensive cost-benefit framework for evaluating design decisions for a variety of scenarios. The specific objective of this research is to provide guidance regarding the number of available information dimensions to incorporate in a computer-based decision aid. Simulation experiments are conducted with a completely specified model based on the cost-benefit framework (including needed assumptions) to evaluate how many information dimensions to include for a specific information matrix size to achieve a balance between information use costs and decision quality. Based upon extensive simulation analyses for a hypothetical decision maker, the practical guideline found for designers is to include only the top half of the relevant information dimensions in any specific decision support system. Over a large number of repeating choice decisions, the savings in cognitive effort and information gathering costs clearly offset relatively minor losses in decision quality.     

The evolution and problems of model management research

Models are a key resource for organizational decision making. The diversity, complexity, and reusability of this resource result in the need for model management systems. The construction of a model management system involves a modeling task dimension and a design level dimension. The modeling task dimension consists of model formulation, model representation, and model processing. The design level dimension addresses the architectural requirements of a system from a user's standpoint and a computer system's standpoint.The numerous architectures suggested in the model management systems literature address isolated areas identified by these dimensions. The research surveyed in this paper indicates that the primary focus has been on the system view of model representation. Before model management systems can be widely used in organizations, model management researchers must explore systems that address all areas of the task and design level dimensions.In this paper, we identify and justify the necessary dimensions of model management research. Next, the existing model management research is critically reviewed. Finally, neglected research areas are discussed, and investigations necessary for the development of integrated model management systems are suggested.     

基于DNA遗传算法的表面贴装生产线负荷优化分配

印制电路板组装任务的负荷优化分配包含设备约束、工艺约束等大量约束,是电子行业表面贴装生产线中的一类重要优化问题。其优化目标是在生产节拍给定和一定约束条件下,使得不同贴装机负荷均衡,任务分配达到最优。首先,根据不同表面贴装机、不同吸嘴及多种类型元件匹配的的复杂性,提出贴装机任务分配组合优化的问题;然后分析设备和元件的参数、组装可行性、贴装时间,以及贴装优化关系等因素,并提出假设条件,建立了平衡率最大化条件下的负荷分配组合优化的数学模型;最后,针对贴装生产线负荷分配问题的复杂性与特殊性,通过改良编码方式后的DNA遗传算法来优化组合数学模型,计算适应度,并借助MATLAB进行仿真求解,进而找到最优解。结果表明：本文提出的贴装生产线负荷分配方法可以解决带复杂约束的印制电路板组装负荷优化分配问题,提高设备的平衡率和生产效率,促进生产线的优化运行。     

Measuring Sharedness of Team-Related Knowledge: Design and Validation of a Shared Mental Model Instrument

Many researchers have explored how people share and construct similar mental models in teams. They have claimed that successful team performance depends on a shared mental model of team members about task, team, equipment and situation. Most of the literature has illustrated simplified relationships between a team's mental model and their performance without a valid instrument addressing the confined and relevant constructs of a shared mental model. This paper describes the instrument development steps and the conceptual framework for factors associated with shared mental models. After development and refinement, the instrument was finalized for use to measure team-related knowledge. The final instrument consists of 42 items that are linked to the five emergent factors of shared mental models including general task and team knowledge, general task and communication skills, attitude toward teammates and task, team dynamics and interactions, and team resources and working environment.     

基于信息更新的两阶段鲁棒-随机优化调配模型研究

在突发事件的应对中,应急决策过程的灾情信息具有动态性、不确定性等特征,从而使得整个应急救援过程中的决策都必须随信息更新而不断调整,本文在调研国内外相关研究的基础上,以地震为背景提出了基于信息更新的资源调配决策问题。文章结合灾情信息更新的特征,给出了应急救援响应的阶段划分;以此为基础建立了两阶段鲁棒-随机优化模型,通过虚拟储备库点及虚拟临时分发中心点的设计,实现了第一阶段调配结果对第二阶段调配决策的后效性调整决策;根据鲁棒优化及随机优化的特点,设计了相应的原始-对偶及L-Shaped Method算法对模型进行求解;最后,通过CPLEX软件编程求解,并进行情景生成下的算例分析,与其他方法比较分析,证明了文章所设计的模型在灾情信息更新下的优势。     

Machinery of Government in Small States: Issues,Challenges and Innovatory Capacity

Small states present particular challenges to designers of political and administrative systems, and far too often their governing patterns have been imposed by former colonial powers. There are nonetheless excellent examples of efforts to design systems which are appropriate to the needs of the small states themselves. This is explored in relation to the pattern of ministries and departments, the use of executive committees, the structure and size of legislatures, head of state/head of government arrangements, and a range of other machinery-of-government issues. Consideration also is given to factors which can be exploited to develop innovative capacity in small states, and some areas for further research are suggested.     

多心理账户下的群体投资决策规则优化研究

从决策者有限理性角度,引入行为金融于群体投资决策系统,研究了多心理账户下群体投资决策规则优化问题。研究给出了群体投资决策系统诸多非标准金融实证异象行为的金融解释,并指出了决策者金字塔式心理账户结构;研究提出了各个心理账户下离散随机变量的信息度量方法,以行为证券组合理论为内核进行集成建模,揭示了多心理账户下群体投资决策规则的优化机理。     

Job resources and emotional exhaustion: The mediating role of learning opportunities

The Job Demands-Resources model predicts that job demands increase and job resources decrease emotional exhaustion in employees. In this study, we investigated one possible mechanism for this, in order to provide a deeper insight into the role of job resources in this energy-depletion process. We assumed that job resources (autonomy and task variety) reduce emotional exhaustion through the promotion of opportunities for personal growth and development, especially workplace learning. Moreover, we expected that job demands (workload, cognitive and emotional demands) would be positively related to work-related learning opportunities. Our research model was tested in a large and heterogeneous sample out of the Dutch working population (N = 4589), following a cross-validation procedure. Multi-group structural equation modelling revealed that autonomy and task variety promoted learning opportunities, which in turn partially mediated between these job resources and emotional exhaustion. With respect to job demands, our study showed mixed results: cognitive demands promoted learning opportunities, workload frustrated such opportunities, and emotional demands were not significantly related to learning opportunities. Our results contribute to a better understanding of the interplay between job demands, job resources and learning opportunities in the energy-depletion process, and support the need for the promotion of learning opportunities in the workplace.     

An Investigation of Localization as an Element of Cognitive Fit in Accounting Model Representations

Cognitive fit, a correspondence between task and data representation format, has been demonstrated to lead to superior task performance by individual users and has been posited as an explanation for performance differences among users of various problem representations such as tables, graphs, maps, and schematic faces. The current study extends cognitive fit to accounting models and integrates cognitive fit theory with the concept of localization to provide additional evidence for how cognitive fit works. Two accounting model representations are compared in this study, the traditional DCA (Debit‐Credit‐Account) accounting model and the REA (Resources‐Events‐Agents) accounting model. Results indicate that the localization of relevant objects or linkages is important in establishing cognitive fit.     

A framework for sustainable forest resource allocation: A Canadian case study

This paper addresses the problem of public-owned forest resource allocation observed in Canada. An integrated framework based on mill abilities to create value (expressed as economic, environmental and social benefits) is proposed. It encompasses three phases: (1) election of sustainable allocation criteria, (2) evaluation of mill performance with regard to the allocation criteria and (3) allocation of wood volumes according to mill performance. The framework is applied to a case study proposed by Ministry of Forests, Fauna and Parks (MFFP) in Québec. It is implemented as follows: first, the international standards, Forest Stewardship Council (FSC) and Global Reporting Initiative (GRI) are used to identify relevant allocation criteria covering the three sustainability dimensions (economy, environment and society). Second, the Group-Analytic Hierarchy Process (Group-AHP) is used to weight the allocation criteria and evaluate mill sustainability performance. Finally, optimization models are formulated to allocate the wood following two strategies: (1) maximizing the total created value by all mills and (2) promoting inter-firm fairness. The numerical results show that integrating sustainability concerns in the evaluation process has a significant impact on the allocation decisions. Moreover, adopting a wood allocation strategy seeking to guarantee fairness between forest companies is a win–win strategy as it also leads to maximizing the created value with a minimum deviation from the optimal targeted value. Lessons learned from this collaboration with MFFP are presented in order to help other interested researchers and public organizations develop their own roadmap to sustainable public resource allocation.     

Selecting IT applications in manufacturing: a KBS approach

The use of the right type of Information Technology (IT) applications or manufacturing systems is expected to usher in a competitive advantage. Selection of the right type of IT application is, however, a challenging task. When a company, with a given dominant process structure, emphasizes two or more competitive priorities, such as quality, product flexibility, etc., an unaided manager faces a complex decision problem in choosing from alternative IT applications available in the areas of product design through distribution. In this paper, we present a Knowledge Based System (KBS) that would assist managers with the identification of IT applications that are consistent with both the competitive priorities and the process structure. Validation of the system illustrates that its performance is consistent with the human experts, and it has the potential to facilitate effective and swift decision-making in the selection of appropriate IT applications that best match an organization's manufacturing strategy.     

企业高级人才队伍动态稳定模型及决策研究

利用现代robust 控制理论和线性矩阵不等式方法,研究了企业高级人才队伍动态稳定决 策问题. 建立了一种在动态环境中高级优秀人才队伍线性不确定时变动态模型. 讨论了模型建 立的理论依据;给出了高级优秀人才队伍robust 稳定的判别方法和robust 稳定控制决策方法, 以及在各种具体情况下的实际意义;并通过对一个实例的具体分析,验证了所给模型与控制决 策方法的有效性.     

The Mapping of Contingencies in Mental Models Found in Organizations

From a cognitive perspective, mental models held by individuals are thought to guide interactions with objects or systems, including interpersonal interactions. Frameworks that categorize types of interactions in organizations suggest that they are guided by cultures and mental models that range from the egoistic to the cosmos-centric. From a behavioral perspective, what the cognitive approach calls mental models are sets of verbal rules. Therefore, we suggest that behavior analysis could be used to reconceptualize the mental model literature, generating new research questions and more rigorous experimentation. Cognitive constructs such as more expansive mental models may simply be a function of an individual’s or group’s increased attention to interlocking contingencies. Applying behavioral interventions such as acceptance and commitment therapy could be a way to examine the utility of a behavior analytic approach.