EMPIRICAL INVENTORY SIMULATION: A CASE STUDY*

An empirical simulation was used to investigate the economics of minimum-buy policies in the U.S. Army management of spare-parts inventory. An empirical simulation makes use of historical data as direct input to the simulation rather than randomly generated data based on a characterization of the historical data. Empirical simulation alleviates the drawbacks of characterizing historical data with a theoretical distribution; however, because steady-state conditions are not reached, a methodological problem arises in the evaluation of inventory assets at the end of the simulation. Our solution was to minimize this problem by use of a cyclic approach.     

信息系统外包决策的AHP/PROMETHEE方法

针对信息系统外包项目优选这一重要问题,在已有方法的基础上,结合层次分析法与偏好顺序结构评估法,提出了一种基于这两种方法相结合的信息系统外包项目选择决策方法。以管理、战略、技术、经济、质量与风险6项因素作为评价准则,用层次分析法确定信息系统外包项目选择问题的层次结构与评价准则的权重,用偏好顺序结构评估法确定信息系统外包项目的排序,并通过算例说明该方法的有效性。     

大型建筑工程项目资源配置模型及策略研究——基于系统动力学的建模和仿真

大型建筑工程项目多类型资源的有效配置,是现阶段项目管理理论与工程管理实践面临的关键问题,特别是在考虑工艺顺序和间歇时间的工作可操作性特点,以及多资源之间反馈影响的情况下。通过整合挣值法和系统动力学理论,在分析资源可用性和工作可操作性之间因果关系的基础上,本文构建了大型建筑工程项目多资源配置的系统动力学模型。以上海市重大工程投资统计数据作为模型参数依据,模型的仿真结果表明:建筑工程项目不同类型资源其配置重要性与系统影响性存在显著差异,在制定资源配置策略时应同时考虑项目运作方式的特征与多资源之间的匹配,资源不匹配则容易导致资源配置系统失去稳态或策略失效。这为进一步研究项目管理中多资源配置提供了理论参考和实践支持。     

Production strategy decisions a simulation model approach

Model building in physical, statistical, simulation or other form, is making an increasing contribution to the problem solving methodology in economics, industry, government, and technological development (1). More specifically, in the present context, simulation models can offer a distinctive and valuable contribution to the understanding by management of complex business systems, interactions and environment and indicate ways toward improvement, financial and otherwise (2). The advent of powerful computers in the last few years is the decisive factor which has decided the means of realizing the full potential of simulation models, hitherto unattainable because of the vast amount of data processing and calculation required. The purpose of this article is to indicate the approach to and scope of a computerized simulation model for long term production strategy decision making (3). While the model relates to the system and data of a specific production unit, manufacturing electronic components, the principles are widely applicable in any size and type of company. It is not a specifically large company technique.     

An integrated modelling approach for raw material management in a steel mill

An integrated modelling approach combining optimisation models with simulation is proposed for coordinated raw material management at steel works throughout the whole supply chain management process. The integrated model is composed of three components: ship scheduling, yard operation simulation and material blending models. The ship scheduling model determines which brands, how much and when they should be arrived, and the problem is modelled as mixed integer linear programming. The simulation model is used to simulate the whole processes from ships’ arrivals to the retrieval of the materials through the berthing and unloading the raw materials. Finally, the raw material blending model is developed for determining the brand and quantity of raw materials to be used. The proposed integrated modelling approach for raw material management has been successfully implemented and applied at steelwork to provide shipping schedules and predict future inventory levels at stock yards. By coordinating all the activities throughout the entire raw material supply chain management process, this article proposes an integrated approach to the problem and suggests a guideline by the appropriate simplification. The quantitative nature of the optimisation model and simulation facilitates an assessment of the risk factors in the supply chain, leading to an evaluation of a wide variety of scenarios and the development of multiple contingency plans. Further research is expected to supplement the ship scheduling models with heuristics for the idiosyncratic constraints of maritime transportation.     

Performance management of suppliers in outsourcing project: case analysis from the financial services industry

This study investigates the characteristics of an effective performance management framework for outsourcing projects in a UK-based financial services organisation and how this may contribute to the success of the outsourcing arrangement. The analysis draws on outsourcing and performance management theory, and uses both primary and secondary data. Valuable information was found on objective setting, performance measurement and performance improvement in the outsourcing project. An adapted version of the Balanced Scorecard, termed a Logic Scorecard, is suggested as a measurement tool; a service credit system and a continuous improvement schedule used to enhance supplier performance. The performance management framework, which is one of the pillars of the supply chain operations reference (SCOR) model, was developed, and provides practitioners with step-by-step guidance for the implementation of performance management in outsourcing projects. This combines both suggestions for performance management before and after the outsourcing decision, thus considering the entire outsourcing lifecycle. The proposed 10-step framework for outsourcing not only incorporates strategic propositions but also shows its implementation at an operational level.     

SIMULATION OF INFORMATION CHOICE

Beginning with the information economics framework and a multi-period decision model [15], this paper considers the use of computer simulation methods within an information system choice environment. Actual decision behavior is replaced by optimal decision rules, and simulation is used to evaluate the effects of parameter changes in the environmental model. Simulation is shown to be functional (1) in estimating the value of alternative information structures within a fifteen period decision model and (2) in providing sensitivity and statistical data which would be useful both for different decision maker utility functions and for a variety of information system design questions.     

The Effect of Forest Management Strategy on Carbon Storage and Revenue in Western Washington: A Probabilistic Simulation of Tradeoffs

The objectives of this study are to understand tradeoffs between forest carbon and timber values, and evaluate the impact of uncertainty in improved forest management (IFM) carbon offset projects to improve forest management decisions. The study uses probabilistic simulation of uncertainty in financial risk for three management scenarios (clearcutting in 45‐ and 65‐year rotations and no harvest) under three carbon price schemes (historic voluntary market prices, cap and trade, and carbon prices set to equal net present value (NPV) from timber‐oriented management). Uncertainty is modeled for value and amount of carbon credits and wood products, the accuracy of forest growth model forecasts, and four other variables relevant to American Carbon Registry methodology. Calculations use forest inventory data from a 1,740 ha forest in western Washington State, using the Forest Vegetation Simulator (FVS) growth model. Sensitivity analysis shows that FVS model uncertainty contributes more than 70% to overall NPV variance, followed in importance by variability in inventory sample (3–14%), and short‐term prices for timber products (8%), while variability in carbon credit price has little influence (1.1%). At regional average land‐holding costs, a no‐harvest management scenario would become revenue‐positive at a carbon credit break‐point price of $14.17/Mg carbon dioxide equivalent (CO₂e). IFM carbon projects are associated with a greater chance of both large payouts and large losses to landowners. These results inform policymakers and forest owners of the carbon credit price necessary for IFM approaches to equal or better the business‐as‐usual strategy, while highlighting the magnitude of financial risk and reward through probabilistic simulation.     

Reproducibility and replicability crisis: How management compares to psychology and economics – A systematic review of literature

The past decade has been marked by concerns regarding the replicability and reproducibility of published research in the social sciences. Publicized failures to replicate landmark studies, along with high-profile cases of research fraud, have led scholars to reconsider the trustworthiness of both findings and institutionalized research practices. This paper considers two questions: (1) Relative to psychology and economics, what is the state of replication and reproduction research in management? (2) Are the disciplines equally advanced in the use of methods applied to study the replication problem? A systematic literature review identified 67 studies pertinent to these questions. The results indicate that the replication prevalence rate in management studies lies almost exactly between those of psychology and economics, while a high level of variation between management and other business-related disciplines can be noted. Further, similarly to psychology, but unlike economics, the surveys of published replications tend to report high replication success rates for management and other business-related disciplines. However, a comparison with recently obtained results in preregistered multi-study replications in psychology and economics suggests that these rates are almost certainly inflated. Method and data transparency are medium to low, often rendering attempts to reproduce or replicate studies impossible. Finally, the understanding of the replicability problem in management is held back by the underutilization of methods developed in other disciplines. The review also reveals that management, psychology, and economics exhibit strikingly different practices and approaches to replication, despite facing similar incentive structures. Disciplines in which replication and reproduction attempts are rare and which frequently involve authors of the original study in replication attempts lack strong deterrents against questionable research practices; thus, they are less likely to deliver replicable results.     

Finding and Implementing Energy Efficiency Projects in Industrial Facilities

This study addresses the challenges of finding and implementing profitable energy efficiency (EE) projects, a critical foundation for sustainable operations. We focus on manufacturing enterprises, but many of our findings apply also to the back office of service operations. Our starting point is that, in nearly every industrial enterprise, there are many profitable EE projects that could be implemented but are not. An oft‐cited hindrance to implementation is the lack of an internal management framework in which to find, value, and execute these projects. Using a conceptual approach, we rely on proven sustainable operations tools to develop such a framework. We identify three major value drivers of EE projects: savings intensity, “green” image, and project complexity. We then describe a framework for understanding the context of EE projects in industry, with an underlying analytic foundation in optimal portfolio analysis. A case study of a large manufacturing site is used to illustrate emerging best practices—based on Kaizen management principles—for integrating EE project management with operations, engineering, and strategy.     

人员管理的经济方法：过去的成就与未来的方向

人事经济学是最近不到20年在经济学和人力资源管理的交接地带兴起的一个新领域,它将经济学用于考察企业内部组织和人力资源管理问题,对现代人力资源管理产生了深远影响.本文对该领域过去的主要成就和未来的研究方向和国内研究动态进行综述.     

Econometric analysis and managerial decision making

Econometric analysis is concerned with the quantitative relationships between economic variables and it can provide an important input into the decision making process of managers. Typically econometrics differs from other apsects of management science in that it considers problems primarily, though not exclusively, from a background of economics rather than of other disciplines and behaviour is usually dealt with at higher levels of data aggregation than the individual firm.This paper considers some applications of typical econometrics to the general area of managerial decision making, where primarily the techniques have a role to play in assisting the general process of data analysis. Initially discussion is pointed towards the use of the analysis for predictive purposes and the contrast with time series methods. Subsequently examples are presented where the objective is to obtain a better understanding of individual economic relationships that aim to be important inputs into the decision making process, for example cost and revenue analysis. Finally, an example is given of how these ideas contribute more generally to the activity of model building for the firm as a whole both for the purpose of forecasting and policy simulation.     

The use of performance measurement as a basis for project control of offshore modification oil and gas projects

The methods presented in this article are based on the qualitative and quantitative analysis of close-out data drawn from a portfolio of 38 modification projects. The primary premise is that modification projects are intrinsically subject to quantity and complexity growth during the course of detailed engineering as a consequence of the indeterminate interface with the existing facility. The normative project control routines need to be supplemented by material take-offs-based weight monitoring as a basis for re-estimation and re-calibration of the project baselines as detailed engineering proceeds in order to mitigate this uncertainty as early as possible. Similarly, estimating needs to be based on norms drawn from performance measurement of modification work rather than extrapolations from greenfield projects, particularly the work performed on the platforms. This article presents a portfolio of project control methods based on the performance measurement principle covering the short term of single projects as well as the longer term multi-project perspective.     

Resilience Analytics with Application to Power Grid of a Developing Region

Infrastructure development of volatile regions is a significant investment by international government and nongovernment organizations, with attendant requirements for risk management. Global development banks may be tasked to manage these investments and provide a channel between donors and borrowers. Moreover, various stakeholders from the private sector, local and international agencies, and the military can be engaged in conception, planning, and implementation of constituent projects. Emergent and future conditions of military conflict, politics, economics, technology, environment, behaviors, institutions, and society that stress infrastructure development are prevalent, and funding mechanisms are vulnerable to fraud, waste, and abuse. This article will apply resilience analytics with scenario‐based preferences to identify the stressors that most influence a prioritization of initiatives in the electric power sector of Afghanistan. The resilience in this article is conceived in terms of the degree of disruption of priorities when stressors influence the preferences of stakeholders, and ultimately a prioritization of initiatives. The ancillary results include an understanding of which initiatives contribute most and least across strategic criteria and which criteria have the most impact for the analysis. The article concludes with recommendations for risk monitoring and risk management of the portfolio of stressors through the life cycle and horizon of grid capacity expansion.     

子网络视角下项目群合同项目工期延误诊断模型研究

项目群工期延误诊断是项目群进度目标控制的一项重要任务。总时差可用于判断项目群中某项工作延误对项目群总工期的延误程度,但没有解决某项工作延误对其自身合同项目和后续合同项目工期延误程度的判断问题。本文根据多项目管理和项目群管理理论,通过引入项目群子网络,研究并构建了基于子网络的项目群结构。在此基础上,运用关键路径法（CPM）,系统地研究了因子网络中合同项目某工作工期延误对自身子网络以及项目群中后续子网络工期的影响,提出了子网络后主链定理以及前主链总时差定理,从而实现子网络视角下项目群合同项目工期延误的诊断分析。结合算例进行了具体阐述与应用。最后就如何应用人工智能算法实现项目群进度及其影响因素进行实时监控提出研究思路。本文研究成果为子网络承包商的工期延误责任划分以及索赔提供依据。     

同时考虑博弈支付与有限市场容量的绿色建筑与传统建筑共生研究

发展绿色建筑是减少温室气体排放的有效途径之一。基于微观市场中绿色建筑和传统建筑市场容量有限的特征,结合共生理论与博弈支付矩阵,构建了绿色建筑与传统建筑的独立共生密度博弈模型;在分析模型稳定后运用系统动力学软件仿真了博弈双方数量的动态变化特征。研究结果表明：模型存在唯一的共生稳定点,模型的稳定条件密切相关于绿色建筑与传统建筑的博弈支付矩阵,与绿色建筑和传统建筑的净复制率无关;政策激励的有效性与微观主体的行为选择密切相关。将中国绿色建筑的实际数据应用本模型进行仿真,结果表明模型可有效揭示和解释中国绿色建筑和传统建筑的共生博弈发展过程。模型和模型仿真结果可有效地为促进绿色建筑的发展提供技术支持和理论依据。     

基于元网络分析的重大基础设施建设项目风险评估框架与实证

重大基础设施项目具有战略性、集成性、复杂性等特征，项目容易受到多种风险因素的综合影响，导致项目目标的偏离。现有风险评估与风险决策的方法缺乏对于风险因素、风险事件之间关联的分析。为了实现重大基础设施建设项目综合系统的风险评估，本文采用元网络分析方法，构建项目目标、风险事件和风险因素的交互模型，揭示重大基础设施风险事件发生机制的黑箱过程。风险评估过程中，通过多个网络叠加运算分析每个风险因素对于各种风险事件以及项目各目标的影响情况，改进了以往仅对风险因素单一影响程度的风险评估方法。同时，本研究选择我国某河流水电站过坝运输项目方案比选的风险评估过程验证方法的适用性。