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Located in the Mid-Atlantic region of the United States, Eastern Truss Company produced trusses used in construction of both large warehouses and custom homes. This case presents the student with the opportunity to analyze the critical factors associated with the decision of whether Eastern should adopt a new production technology and whether cash flows from reduction of temporary workers will cover adoption coasts. The student must evaluate the decision to adopt the production technology through the lens of operations management tools. This case is appropriate for undergraduate business studies in the field of operations management.

Case study.

Undergraduate operations management.

This paper aims to examine a congestion situation of a certain type of restaurant in a theme park (Tokyo Disney Resort) by a simulation based on Little’s law, which is a basic principle in Queueing theory. In the restaurant, a guest (customer) lines up to order, pay and receive dishes. A problem is that even when a guest can easily find vacant tables, it takes a long time to receive dishes. Because guests can see there are vacant tables, there are many tweets of complaints. This situation is a factor to undermine customer satisfaction.

This paper proposes dedicated special menu lines only providing special set as one solution that can be realized at a low cost to reduce vacant tables. Here, if the number of special menu lines is fixed, the difference between a queue in regular lines and that in special menu lines will be big. To shorten the difference, the author proposes a technique to regulate by using feedback control (Proportional control or Fuzzy control).

The simulation result shows that the number of vacant tables decreases by about 16 per cent compared with the current situation.

This paper considers a specific restaurant, but the proposed method can be applied to the same type of restaurant in the theme park. If the restaurant in the theme park is crowded, the feedback control of the queue brings new possibilities.

本论文旨在检验主题公园（日本迪士尼）内饭店的拥堵情境。本论文采用同步模拟的方式，以等候理论的基础原则—科特尔法则为基础，来进行检验。在一家饭店中，客人（顾客）排队点餐、付款、以及拿到食物。其中问题是，即使客人能够轻松找到空桌位，而等餐的时间非常长。因为客人看到有空桌位，所以客人会有很多抱怨。这种情境会严重影响顾客满意度。

本论文提出一种特别菜单行数设计来用低成本的方式解决空桌位的问题。如果特别菜单行数是固定的，那么使用常规菜单和特别菜单所产生的排队现象会大有不同。本论文借助反馈控制（比例控制或模糊控制），提供一种调节方法以减少这种差别。

模拟结果表明空桌位的数量同现有情境相比，减少了16%.

本论文采用特定的饭店，但是提出的方法可以推广到同种类型的主题公园饭店。如果主题公园饭店人满为患，那么使用反馈控制来调价排队情况将带来新可能。

主题公园、饭店、等候理论、科特尔法则、模糊控制、比例控制

The dilemma faced by many batch‐manufacturing operations is the trade‐off between reducing lead times and manufacturing throughput. Using Little’s Law and the theory‐of‐constraints analysis, the authors have developed a methodology to optimise such dilemmas. The solution to this problem is to find the point in the operation of the plant where throughput is maintained at acceptable levels, but the lead time through the plant is maintained at or near a minimum. At such a point, the optimum level of work in progress (WIP) will be obtained. Such principles have been applied in this research project to a metals manufacturer. The difficulty with this case study is that complexity of the product mix and manufacturing flow renders simple analysis incomplete. By utilising a discrete event simulation of the manufacturing facility, we have been able to identify bottlenecks within the plant. From here we have developed a tool that automatically predicts the optimum level of WIP, depending upon such parameters as product mix and batch sizes. The results show significant improvement over the current practices, and over maintaining a constant WIP level. The results highlight the power of the constraint principles, and the value in evaluating and choosing the best methods for managing change through simulation.

To describe research and development (R&D) as a tool of strategic growth. The world's top performing companies share a common characteristic: their superior ability to develop and introduce new products faster and cheaper than their competitors. As a matter of fact, effective product innovation is the key to growth, even survival, for almost any business.

The author discusses how innovation in R&D could serve as a differentiating strategic business tool. The paper is based upon the authors 15 years of experience in the area of R&D and new product development. The paper is very creative in two respects. First, it looks at strategic R&D as the differentiating strategic “weapon” companies can use to separate themselves from the competition. Second, it uses many of the manufacturing, operations management tools and methodologies and applies these to innovation in R&D. The paper discusses methods to optimize a company's R&D efforts.

The executives emphasized the importance and criticality of organic growth and innovation as a major business concern and opportunity for their companies' future success. While strategies including acquisitions and continuous process improvement have proven successful but very difficult to sustain, expensive and risky to integrate, “Innovation, and innovation in research and development” in particular, can provide the advantage that world class organizations need to create the sustainable growth year after year. Innovation in R&D can be a strategic weapon in which top companies employ definable strategies and practices to catalyze high levels of organic growth, support above average margins even in mature businesses, and separate themselves from the competition.

This paper is a very interesting read for high‐level managers and executives interested in the field of R&D and new product development.

In recent years, time‐based competition (TBC) has drawn the attention of several practitioners and academicians. Much evidence has been put forward from case studies in order to show the benefits that derive from time compression. Nevertheless, there is a lack of conceptual models and operating tools to support lead‐time reduction. Provides a conceptual framework for modelling the lead time of business processes in order to design effective re‐engineering. Two levels of lead‐time modelling have been identified: an aggregate level, which accounts for the relationships between lead times of different phases of a process, and a detailed one, which allows the mechanisms of lead‐time making to be clearly understood. Reviews existing time models and proposes two new detailed models in order to cope with the growing need for process re‐engineering. Presents these models in terms of time components and composition laws. Suggests a process taxonomy to select the suitable lead‐time models depending on the process characteristics at both the aggregate and detailed level. Finally, shows how detailed models could be used to link lead time to process performances on the one hand and to managerial levers on the other. Thirteen time‐drivers, affecting the lead time of a given process and its basic components, have been identified.

Service experiences and waiting lines are often – unfortunately – seen to go hand in hand. This chapter explains why this is the case. Beginning with an exploration of capacity and operating constraints, discussion then delves into both the mathematical origins and psychological implications of waiting lines. The final section offers hope to managers and guests alike, with a survey of different operations strategies and tactics that can eliminate or abate the need to wait.

The purpose of this research is to explore the utility of autonomous transport across two independent airframe maintenance operations at a single location.

This study leveraged discrete event simulation that encompassed real-world conditions on a United States Air Force flight line. Though the Theory of Constraints (TOC) lens, a high-demand, human-controlled delivery asset is analyzed and the impact of introducing an autonomous rover delivery vehicle is assessed. The authors’ simulations explored varying numbers and networks of rovers as alternative sources of delivery and evaluated these resources’ impact against current flight line operations.

This research indicates that the addition of five autonomous rovers can significantly reduce daily expediter delivery tasks, which results in additional expertise necessary to manage and execute flight line operations. The authors assert that this relief would translate into enhancements in aircraft mission capable rates, which could increase overall transport capacity and cascade into faster cargo delivery times, systemwide. By extension, the authors suggest overall inventory management could be improved through reduction in transportation shipping time variance, which enhances the Department of Defense’s overall supply chain resilience posture.

When compared against existing practices, this novel research provides insight into actual flight line movement and the potential benefits of an alternative autonomous delivery system. Additionally, the research measures the potential savings in the workforce and vehicle use that exceeds the cost of the rovers and their employment.

The food and beverage industry, particularly the agro‐processing and packaging industry, plays a critical role in the economies of Latin America and Caribbean countries. To remain competitive and to increase competitiveness, companies operating in this industry must achieve operational efficiency – where one contributing factor would be the efficient management of their work‐in‐progress (WIP) inventories.

Constructs from related manufacturing management research areas such as manufacturing strategy and coordination theory, are incorporated into a conceptual framework to examine the reasons WIP are needed in food plants. The framework is used to inform the development of an audit tool, which is applied in a case study.

An audit tool is proposed, which can be used by practitioners to review the structural and infrastructural decisions that impact WIP.

The audit tool is applied in one case study. Further application of the tool will test its overall comprehensiveness.

The audit tool can be used as part of a structured decision making process.

The paper brings together a number of constructs to create an audit tool that can be used in both greenfield and existing plants in the food industry.

The paper aims to investigate the cardiology department’s operational system for improving flexibility by minimizing the patient waiting time and simultaneously maximizing the utilization of service capacity in an uncertain environment. This article also proposes a policy framework that suggests a pool of additional resources and inter-firm collaboration can boost healthcare service delivery excellence.

A discrete event simulation (DES) approach is followed for modeling patient flow and determining the service capacity to respond to demand variability and uncertainty. The model's outputs are used to minimize patient waiting time, maximize the utilization of the resources and match the service capacity with the patient demand.

This research has tested two hypotheses and proved that an increase in waiting time decimates the throughput rate, and additional resources deployment in bottleneck activity positively impacts the throughput rate. The simulated scenarios prescribe an enhanced service capacity with quality care and further contribute to operational performance in reduced waiting time and cost. The results indicate that flexibility reduces the patient waiting time and maximizes the throughput rate.

The study guides the healthcare policymakers to develop flexible competence and facilitate service mechanisms that are adaptive and robust while operating under a volatile environment. The article contributes to the healthcare literature that conjoins flexibility through simulation and resource utilization.

This research is based on real-life primary data collected from healthcare providers. This study adds value to the healthcare systems to adopt strategic decisions to build flexibility through resource allocation, sharing and coordinated care.

Petri net (PN) and queuing theory are used in performance analysis of a flexible manufacturing system (FMS). They are used to determine the FMS measures of performance. These measures of performance include optimal work‐in‐process (WIP), lead time, production rate, machine utilization, and number of servers at each station. The purpose of this paper is to present a comparison between PN and queuing network tools to determine the optimum values for FMS measures of performance.

PN model with dual kanban and closed queuing network are used for analysis and performance evaluation of FMS. Integrated network analyzer and Lingo softwares are used for performance evaluation of FMS by PN tool. CANQ software is used for performance evaluation of FMS by queuing network. In both the approaches, the throughput is bounded by the utilization of the bottleneck machines.

The comparison shows that for the given number of servers, PN gives better values of performance measures for FMS. The PN optimization gives minimum WIP corresponding to the maximum production rate. Minimum WIP leads to minimum lead time.

The results are concluded based on one case study. In future research, the results may be achieved by doing more case studies with different numbers of system parameters and/or parameter settings.

Using the PN model, the production manager may design, analyze, evaluate, and even optimize the layout of the production system for minimum WIP, maximum throughput, and reduced lead time. The determination of the total WIP, total number of stations in the production system, and the number of servers at each station may be helpful in shop floor management. It may result in more production efficiency along with ease of supervision.

This paper presents a first novel comparison of its kind between PN and queuing network for evaluation of FMS.