Alok K. Verma

Improving agility of supply chains using base stock model and computer based simulations

Purpose – The purpose of this paper is to deal with the application of the stochastic inventory model to the three‐tier supply chain and verify the values obtained by mathematical model in physical simulation.Design/methodology/approach – The paper investigates three‐stage serial supply chain with stochastic demand and fixed replenishment lead‐time. Inventory holding costs are charged at each stage, and each stage may incur a consumer backorder penalty cost charged by primary supplier to secondary supplier. The customer‐demand follows Poisson distribution. The base stock model is implemented for inventory control at both suppliers. Physical simulation is then designed in such a way that it satisfies all the assumptions for mathematical model. Simulation is run to verify the values obtained from mathematical model.Findings – Computer simulation is designed to include all the assumptions made by mathematical model. Hence, mathematical base stock model and computer simulation model are comparable. Demand fol...

Parametric Study of Surface Finish in End Milling Using Robust Design Techniques

Surface finish in end milling depends upon a number of variables, such as feed rate, cutting speed, tool material, etc. The relative effect of these variables on surface roughness is not understood very well. The Taguchi method is used in end milling process to identify variables having major influence on surface finish. Partial factorial design using L9 orthogonal array is used in the design of experiments. Signal to Noise ratio analysis along with analysis of variance is used to study the effect of these parameters on surface finish. Knowledge about these relationships will help a process planner or a machinist optimize the cutting process with respect to surface finish.Copyright

Implementing advanced manufacturing technology in organizations: a socio-technical systems analysis

The socio-technical systems model is applied as a framework for analyzing the effective implementation process of advanced manufacturing technology (AMT) in organizations. Through technical and social analysis of AMT in the organizational context, it is concluded that the joint optimization of the implementation is affected by four factors: quality of work life; congruency; concurrence; and flexibility. In order to achieve the joint optimization, seven design/redesign principles are proposed.<<ETX>>

Design of Simulation Tools for Trainig Programs in Lean Manufacturing

Lean Manufacturing is a powerful philosophy, which advocates minimization of waste throughout the value stream both within the organization and enterprise which includes the supply chain. A concept, which was first used by automobile manufacturers to enhance their operational efficiencies, Lean focuses on driving out non-value added activities from a company’s operation, while streamlining its value added activities. A number of companies in the United States have adopted the Lean Manufacturing philosophy to reduce cost and increase efficiency. To augment the existing training programs five new simulation tools in Ship Design Processes, Supply Chain Integration, Ship Repair Processes, Value Stream Mapping and Scheduling were developed under a grant from National Shipbuilding Research Program (NSRP) by Old Dominion University, Northrop Grumman Newport News and South Tidewater Association of Ship Repairers. The paper will discuss the design, development and implementation of two of these new simulation tools.Copyright

Using Senior Design Project to Teach Design for Use of a Mechatronic Device

Recent innovations have focused on the development of products which have embedded features such as sustainable energy power sources and intelligent controls which take into account energy efficiency and environmental variables that drive the total cost of the product ownership. The primary purpose of such efforts is to promote products that are more energy efficient and that are making smaller environmental footprint during their lifecycle. Lower cost, easy assembly and better manufacturability are some of the parameters that are part of the Design for Excellence (DfX) methodology. One of the most significant expenses that customers will face will occur during the use stage of the product lifecycle. This paper discusses the application of Design for Use (DfU) strategies on a conceptual design and prototype of a solar skimmer for a swimming pool. A group of senior students in mechanical engineering technology program completed this project as their requirement for graduation.

AGILE MODELING AND OPTIMIZATION OF END MILLING

The rising demand for precision and quality in manufacturing necessitates that vast amounts of manufacturing knowledge be incorporated in manufacturing systems. Surface finish in end milling depends upon a number of variables such as cutting speed, feed rate, spindle speed, radial depth of cut, etc. The relative effect of these variables on surface roughness and machining time is quite considerable. A complex relationship exists between these process parameters and hence there is a need to develop models which can capture this complex interrelationship and enable fast computation of the average surface roughness and machining time based on process parameters. Neuro Fuzzy (NF) modeling has gained prominence recently on account of its fast reaction times, improved ease of operation and flexibility to respond to change in process parameters. In the present work, initially a Neuro Fuzzy Model is trained with experimental results of end milling. Subsequently, a generic approach is developed for optimization of end milling where the applicability and effectiveness of Neuro Fuzzy Model for function approximation is used to rapidly estimate average surface roughness and machining time in an integrated framework of Hybrid Stochastic Search Technique (HSST) to form a Neuro Fuzzy Hybrid Stochastic Search Technique (NFHSST). The results indicate that the NFHSST heuristic converges to better solutions rapidly as it provides the values of various process parameters for optimizing the objectives in a single run. Thus, NFHSST assists in the improvement of quality by developing multiple sound parts in an agile manner.

Project Based Activities to Attract Students to Marine Engineering and Technology Careers

During the past several years, workforce issues have immerged as a dominant concern for shipbuilding and repair companies. Related issues include concern about “aging” of the workforce, lack of basic technical education, career transition processes, recruitment and training of the new workforce, retention and training of the incumbent workforce, image of the industry, and lack of career information for middle and high school students. Large turnover combined with retirement of aging workforce is anticipated to create large demands for qualified workforce. The Shipbuilding and Repair Career Day Events (SBRCD) project was conceived in response to this critical need of workforce in shipbuilding and repair industry. This project was funded by the National Shipbuilding research Program to increase awareness about careers in marine industry. The paper discusses the multi-pronged effort within the SBRCD project to inform and engage middle and high school students, teachers and counselors about career opportunities in this industry. The paper also discusses the design and development of four simulation activities known as marine kits to engage students in shipbuilding related projects. These activities are tied to Virginia Standards of Learning (SOL) so teachers can use them in classrooms without loosing time. The Marine Kits were pilot tested and results are discussed.Copyright

Outcome Based Assessment and Continuous Improvement Model for Engineering Technology Programs

Assessment and continuous improvement are essential and critical processes for higher education. Development and implementation of such processes are not only required by the Accreditation Board for Engineering and Technology (ABET) as part of the accreditation process but are also necessary for the maturation and development of any engineering technology program. The assessment and continuous improvement plan discussed here was developed at Old Dominion University (ODU) and implemented during the last accreditation cycle within the Engineering Technology Department. The plan is based on two cycles of assessment and evaluation, a short cycle of one year and a long term cycle of three years. The plan includes a variety of assessment methods and tools. In addition to assessing the achievement of program outcomes, the plan allows assessment of program objectives and goals. A method for individual course assessment is also presented. Issues related to institutionalization of the assessment process are also discussed.Copyright

Comparison of Cost Factors in Laser Processing of Materials and Traditional Metal Cutting Processes

Comparison of cost factors between traditional metal cutting process and laser cutting process has been made. The paper presents a generic cost estimation model for laser cutting of metals. Various types of lasers used in cutting have been discussed as well as the parameters affecting the cutting process.Copyright

Teaching Design and Automation Principles Through a National Robotics Competition

An innovative method for teaching senior project course has been discussed. The method involves use of seniors as mentors for a team of high school students participating in a national robotic competition. The experience offered students an opportunity to lead teams during design and fabrication of various components of the robot while meeting specific deadlines. Students learnt the principles of design and automation while teaching their high school counterparts.Copyright