An integrated control framework for discrete event systems

The overall objective of this dissertation is to investigate various control theories on DES and develop a novel control framework which combines a preventive control problem of establishing behavioral correctness with the performance-oriented control problem of optimizing predefined performance objectives. The primary question which should be answered is \u27How should a real-time controller make decisions for short-term scheduling anddispatching with an objective of achieving high-levels of performance when there are qualitative performance measures involved?\u27 --Introduction, page 5

Analysis of the effects of coolant/lubricant aiming in machining operations

Cutting fluid application methods have became a major problem for companies heavily involved in machining operations due to environmental concerns as well as cutting efficiency. An alternative coolant/lubricant system, known as STAMP, (Small Volume Organic Oils Transported by Air Stream For Cooling/Lubrication in Machining Processes) has been developed by The Computer Integrated Manufacturing (CIM) Team at the University of Missouri-Rolla. Research has been conducted with this new system which addresses environmental issues while maintaining cutting fluid performance. The STAMP system uses a small volume of environmentally benign soybean oil based fluid transported in an air stream to cool and lubricate the tool and work during machining processes. The system employs a nozzle, which was developed to mix and spray the air and the oil precisely into the cutting zone. This thesis is a study of optimizing the aiming methods for the STAMP system. This research focuses on developing a stable and accurate aiming system for the application of cutting fluid and the analysis of the effectiveness of cutting operations by examining cutting forces and power consumed. The research described here also involves further developing the cutting fluid delivery system (Nozzle), which was created in the previous studies, making it more useful and functional by optimizing the fluid application direction. Since the thesis is a part of the family of the STAMP system research, certain criteria were followed such as using soybean oil as the cutting fluid and using the hardware and mixture parameters of the previous nozzle for new nozzle development --Abstract, page iii

A terrain risk assessment method for military surveillance applications for mobile assets

This study proposes an analytical and flexible terrain risk assessment method for military surveillance applications for mobile assets. Considering the risk as the degree of possibility of insurgent presence, the assessment method offers an efficient evaluation of risk in the surrounding terrain for military combat operating posts or observation posts. The method is designed for unmanned aerial vehicles as the surveillance assets of choice to improve the effectiveness of their use. Starting with the area map and geographical data, the target terrain is first digitized for space representation. Then the data of nine geographical parameters are used to formulate five contributing risk factors. These factors are incorporated in an analytical framework to generate a composite map with risk scores that reveal the potential high-risk spots in the terrain. The proposed method is also applied to a real-life case study of COP Kahler in Afghanistan, which was a target for insurgent attacks in 2008. The results confirm that when evaluated with the developed method, the region that the insurgents used to approach COP Kahler has high concentration of high-risk cells

Developing a new industrial engineering curriculum using a systems engineering approach

This paper reports on the development of an engineering curriculum for a new industrial engineering programme at a medium-sized private university in the northeast United States. A systems engineering process has been followed to design and develop the new curriculum. Considering the programme curriculum as a system, first the stakeholders have been identified, and some preliminary analysis on their needs and requirements has been conducted. Following that, the phases of conceptual design, preliminary design, and detailed design have been pursued during which different levels of validation, assessment, and evaluation processes have been utilised. In addition, a curriculum assessment and continuous improvement process have been developed to assess the curriculum and the courses frequently. The resulting curriculum is flexible, allowing the pursuit of accelerated graduate programmes, a second major, various minor options, and study-abroad; relevant, tailored to the needs of industry partners in the vicinity; and practical, providing hands-on education, resulting in employment-ready graduates

Supply Chain-Related Adverse Events and Patient Safety in Healthcare

This research investigates adverse events and patient safety in healthcare due to poor supply chain management practices, and inadequate and disorganized product validation procedures. Focusing on commodity medical and surgical products, this research investigates correct product validation points for maximum patient safety. This study also explores benefits of standard product identifying technologies such as HIBC or GS1 data standards as well as automated validation systems such as barcode or Auto ID to minimize workflow interruptions. Site visits and phone interviews are conducted with six healthcare providers to document common product validation practices and procedures. Based on observations and collected data, a simulation model is developed. Different scenarios are compared for patient safety, care delay, and system efficiency. The results show that validation points during PAR picking or bedside product administration, and warehouse picking operations provide optimal overall system performance. The results also indicate that standard product identifying technologies and automated validation systems significantly impact the efficiency of supply chain

An auction-based framework for resource allocation in disaster relief

PurposeThe purpose of this paper is to address the inefficiency problems in procurement operations in disaster relief logistics which are mainly due to the lack of coordination among less organized suppliers and partnerships. Such problems lead to poor responsiveness and hinder timely procurement of required goods.Design/methodology/approachAn auction‐based framework for procurement of goods, which is suitable for a single coordinating platform in disaster relief logistics, is proposed. Integer programming formulations are used in auctioning operations. A simulation model that generates problem instances is used to evaluate and tune system‐level design parameters.FindingsDesign parameters greatly affect the behaviour and responsiveness of the system and the performance of the auction‐based framework in different problem instances. Combinations of those parameters may allow suppliers with limited capacities to become more involved in the bidding process. In addition, the procurement shares of bidders may change substantially with different values of the parameters.Research limitations/implicationsEven though the presented framework is inspired from real‐life applications, it is not implemented in real‐life disaster relief operations. The goodness of fit for the framework would best be evaluated by a real disaster case. In addition, transportation scheduling and vehicle routing considerations and budgeting issues are not considered in the framework.Originality/valueThis paper presents an auction‐based framework for less organized suppliers of goods and their partnerships, such as local humanitarian organizations, private companies, and standby partners. The presented framework offers a background for coordination during disaster relief operations which provides opportunities to act as a set of organized entities. This background also helps those entities coordinate their efforts to enhance the capabilities of local governments and NGOs.</jats:sec

Methodical analysis of inventory discrepancy under conditions of uncertainty in supply chain management

This study presents two compensations methods for inventory discrepancy caused by demand, supply and lead time uncertainty as well as inventory related errors. The first method increases the resistance of supply chain by incrementing safety stock levels while the second method controls and corrects inventory discrepancy based on estimated errors. System-level errors are categorised and modelled under the best and the worst possible conditions to characterise and investigate the behaviour of discrepancy between on-hand and recorded inventory in a supply chain. Numerical analyses are performed to observe inventory and discrepancy behaviour to quantify the benefits of the methods. The results indicate that inventory errors can be characterised as an extra source of demand in supply chain. Incrementing the safety stocks based on inventory records can decrease stock-outs and lost sales but increase the level of on-hand inventory. Controlling and correcting inventory discrepancies, however, keeps low inventory

Tool allocation in flexible manufacturing systems with tool alternatives

Abstract In this paper, a heuristic approach for tool selection in flexible manufacturing systems (FMS) is presented. The proposed approach utilizes the ratio of tool life over tool size (L=S) for tool selection and allocation. The proposed method selects tool types with high L=S ratios by considering tool alternatives for the operations assigned to each machine. The performance of the method is demonstrated in sample problems as static examples, as well as in a simulation study for further analysis. This study also presents a survey of several approaches related to loading and tool allocation problems in FMS, highlights the importance of tooling, and discusses the practical aspects of tool-oriented decision-making. An extended framework, which expands on the L=S concept, is also presented.