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Full-Text Articles in Mechanical Engineering

Silicon Oxide Micromodule Capacitors, W. B. Nowak, J. J. O'Connor Dec 2010

Silicon Oxide Micromodule Capacitors, W. B. Nowak, J. J. O'Connor

Welville B. Nowak

Silicon oxide capacitors have been developed on micromodule wafers (0.310-in. sq. with three termination notches per side). Each microelement contains 1, 2, 3, or 4 capacitors with values of 1120 and 560, 180, 100 and 68 pf per capacitor, respectively. The 1120 pf capacitor is double layered. In addition to the general requirements of microelements and micromodules, some of the more important specifications these capacitors must meet are: dissipation factor (DF) not exceeding 0.015, insulation resistance (IR) at 50 volts exceeding 10,000 megohms (25°C) and 750 megohms (125°c), 50 WVDC and 150 volts dielectric withstanding ...


Structural And Magnetic Characterization Of Amorphous Gd₂Fe₁₄B Thin Films, S. E. Bushnell, P. C. Dorsey, W. B. Nowak, C. Vittoria Dec 2010

Structural And Magnetic Characterization Of Amorphous Gd₂Fe₁₄B Thin Films, S. E. Bushnell, P. C. Dorsey, W. B. Nowak, C. Vittoria

Welville B. Nowak

Thin amorphous films of nominal composition Gd₂Fe₁₄B were fabricated on Si (100) substrates using ion‐beam sputtering for the purpose of establishing their structural and magnetic properties at room temperature. X‐ray‐diffraction scans performed on as‐deposited and annealed films revealed an amorphous structure. The as‐deposited saturation magnetization was found to be 8101 G at room temperature suggesting ferrimagnetic ordering with anti‐parallel coupling similar to other heavy rare earth‐transition metal systems. Results from in‐plane and perpendicular ferromagnetic resonance experiments conducted at 9.108 GHz showed the films to be inhomogeneous. This was evident from the ...


The Measurement Of Magnetostriction Constants Of Thin Films Using Planar Microwave Devices And Ferromagnetic Resonance, S. E. Bushnell, W. B. Nowak, S. A. Oliver, C. Vittoria Dec 2010

The Measurement Of Magnetostriction Constants Of Thin Films Using Planar Microwave Devices And Ferromagnetic Resonance, S. E. Bushnell, W. B. Nowak, S. A. Oliver, C. Vittoria

Welville B. Nowak

In this paper we introduce a new technique for measuring the saturation magnetostriction constant (λs) for isotropic polycrystalline thin films. The technique makes use of nonresonant planar microwave structures together with a novel stressing mechanism to induce a shift in the resonant field of a magnetic thin film as measured by a ferromagnetic resonance (FMR) experiment. Measurement of the shift induced by a uniaxial stress allows for determination of λs via a magnetic resonance analysis. Either a slotline device or coplanar waveguide (CPW) was used as the source of the microwave excitation field depending upon the orientation of the dc ...


Magnetic And Structural Investigation Of Heat Treated Ion Beam Sputtered Amorphous Co₇₄Fe₆B₁₅Si₅ Films, V. G. Harris, S. A. Oliver, W. B. Nowak, C. Vittoria, R. J. Culbertson, W. T. Elam, K. H. Kim Dec 2010

Magnetic And Structural Investigation Of Heat Treated Ion Beam Sputtered Amorphous Co₇₄Fe₆B₁₅Si₅ Films, V. G. Harris, S. A. Oliver, W. B. Nowak, C. Vittoria, R. J. Culbertson, W. T. Elam, K. H. Kim

Welville B. Nowak

As-deposited and annealed specimens of ion beam sputtered amorphous Co₇₄Fe₆B₁₅Si₅ thin films were examined to explore the correlation between changes in magnetic properties and atomic structure. Specimens were characterized magnetically, by traditional ac and dc techniques and structurally, via conversion-electron extended x-ray absorption fine structure analysis. Results show significant ordering of the higher order atomic shells around the transition metal ions well below the crystallization temperature. This ordering evolves into a body- centered-cubic configuration around both the Co and Fe ions. Increases in nearest neighbor peak positions in the EXAFS Fourier transforms were observed to correlate with increasing annealing temperatures ...


Magnetic And Microwave Properties Of Ion-Beam-Sputtered Amorphous FeₓCo₈₀₋ₓB₁₅Si₅ Films, V. G. Harris, S. A. Oliver, W. B. Nowak, C. Vittoria Dec 2010

Magnetic And Microwave Properties Of Ion-Beam-Sputtered Amorphous FeₓCo₈₀₋ₓB₁₅Si₅ Films, V. G. Harris, S. A. Oliver, W. B. Nowak, C. Vittoria

Welville B. Nowak

Magnetically soft amorphous films of FeₓCo₈₀₋ₓB₁₅Si₅ (x = 0, 6, 23, 40, 70, 80) were ion beam sputter deposited onto fused quartz for static and microwave magnetic characterization. Films ranged in thickness from 220 to 260 nm and were deposited at rates of 0.1-0.2 nm/s. Saturation magnetization, coercivity, and loop squareness values were extracted from hysteresis loops generated by a vibrating sample magnetometer. Ferromagnetic resonance measurements were taken using a 9.5-GHz cavity with the applied magnetic field both parallel and perpendicular to the plane of the film, yielding values for the g factor, anisotropy field, effective ...


Effects Of Boron Implantation In Films Of Iron-Nickel, J. Ryu, K. Castell, W. Nowak, C. Vittoria Dec 2010

Effects Of Boron Implantation In Films Of Iron-Nickel, J. Ryu, K. Castell, W. Nowak, C. Vittoria

Welville B. Nowak

We have implanted boron ions into films of Fe-Ni alloy composition. A homogeneous distribution of boron was determined from the sputter Auger analysis with a concentration of 18% and 34% for low- and high-dose implantation, respectively. The resistivity of film was increased by a factor of 2 and 4 as a result of low- and high-dose implantation, respectively. The magnetic properties of these films are studied as a function of annealing temperature by using FMR measurements. Both the uniaxial anisotropy field and FMR linewidth are dramatically decreased as a result of annealing at elevated temperatures. The changes of effective magnetization ...


A Bi-Directional Supply Chain Optimization Model For Reverse Logistics, Surendra M. Gupta, Pitipong Veerakamolmal Oct 2010

A Bi-Directional Supply Chain Optimization Model For Reverse Logistics, Surendra M. Gupta, Pitipong Veerakamolmal

Surendra M. Gupta

This paper focuses an supply chain optimization system for reverse logistics. The solution approach employs an adaptation of the Materials Requirements Planning (MRP) technique, termed as components requirements planning, to determine the number of components needed to remanufacture products in each time period throughout the planning horizon.


Greedy Algorithm For Disassembly Line Scheduling, Seamus M. Mcgovern, Surendra M. Gupta Oct 2010

Greedy Algorithm For Disassembly Line Scheduling, Seamus M. Mcgovern, Surendra M. Gupta

Surendra M. Gupta

Remanufacturing, recycling, and disposal recovery operations require the performance of disassembly activities. The disassembly line is the best choice for automated disassembly of returned products, however, finding the optimal balance is computationally intensive with exhaustive search quickly becoming prohibitively large. In this paper, a greedy algorithm is presented for obtaining optimal or near-optimal solutions to the disassembly line balancing problem. The greedy algorithm is a first-fit decreasing algorithm further enhanced to preserve precedence relationships. The algorithm seeks to minimize the number of workstations while accounting for hazardous and high demand components. A hill-climbing heuristic is then developed to balance the ...


A Multi-Phase Fuzzy Logic Approach To Strategic Planning Of A Reverse Supply Chain Network, Kishore K. Pochampally, Surendra M. Gupta Oct 2010

A Multi-Phase Fuzzy Logic Approach To Strategic Planning Of A Reverse Supply Chain Network, Kishore K. Pochampally, Surendra M. Gupta

Surendra M. Gupta

Strategic planning (also called designing) is a challenging aspect of a reverse supply chain network. To effectively satisfy drivers such as profitability, environmental regulations, and asset recovery, only the most economical used products must be reprocessed in only the recovery facilities that have the potential to efficiently reprocess them. Due to uncertainties in supply, quality, and reprocessing times of used products, the cost-benefit function in the literature that selects the most economical product to reprocess from a set of used products is not appropriate for direct adoption. Moreover, due to the same uncertainties, any traditional forward supply chain approach to ...


A Business-Mapping Approach To Multi-Criteria Group Selection Of Collection Centers And Recovery Facilities, Kishore Pochampally, Surendra Gupta Oct 2010

A Business-Mapping Approach To Multi-Criteria Group Selection Of Collection Centers And Recovery Facilities, Kishore Pochampally, Surendra Gupta

Surendra M. Gupta

For a prospective reverse supply chain to operate efficiently, the designing of that chain must involve selection of collection centers and recovery facilities that have sufficient success potentials. These success potentials depend heavily on the participation (in the reverse supply chain) of three important groups that have multiple, conflicting, and incommensurate goals. Therefore, the potentials must be evaluated based on the maximized consensus among the three groups, viz., (i) Consumers whose primary concern is convenience, (ii) Local government officials whose primary concern is environmental consciousness, and (iii) Supply chain company executives whose primary concern is profit. In this paper, we ...


Pricing Of End-Of-Life Items With Obsolescence, Srikanth Vadde, Sagar V. Kamarthi, Surendra M. Gupta Oct 2010

Pricing Of End-Of-Life Items With Obsolescence, Srikanth Vadde, Sagar V. Kamarthi, Surendra M. Gupta

Surendra M. Gupta

Variability in the inflow of end-of-life (EOL) products and fluctuating inventory levels often make the processing of EOL products an economically risky operation for product recovery facilities (PRFs). Choosing an appropriate pricing policy can enhance the performance of PRFs by methodically clearing their inventory and increasing profits. This work presents two pricing models to counter the prospect of product obsolescence that can happen either gradually or suddenly. Product obsolescence can cause demand drop and inventory pile up, both of which could dent the revenues of PRFs. In the first model, gradual obsolescence and environmental regulations that limit the disposal quantity ...


Product Recovery Using A Disassembly Line : Challenges And Solution, Surendra M. Gupta, Askiner Gungor Oct 2010

Product Recovery Using A Disassembly Line : Challenges And Solution, Surendra M. Gupta, Askiner Gungor

Surendra M. Gupta

Disassembly plays an important role in product recovery by allowing selective separation of desired parts and materials. The disassembly line is the best choice for automated disassembly of returned products, a feature that will be essential in the future. It is, therefore, important that the disassembly line be designed and balanced so that it works as efficiently as possible. In this paper, the authors address the disassembly line balancing problem and the challenges that come with it.


Disassembly Process Planning Using Petri Nets, Kendra E. Moore, Askiner Gungor, Surendra M. Gupta Oct 2010

Disassembly Process Planning Using Petri Nets, Kendra E. Moore, Askiner Gungor, Surendra M. Gupta

Surendra M. Gupta

We generate a disassembly PN (DPN) from a disassembly precedence matrix. The resulting DPN can be analyzed using the reachability tree method to generate all feasible disassembly process plans (DPPs), and cost functions can be used to determine the optimal DPP. Since generating the reachability tree is NP-complete, we develop a heuristic algorithm to limit the size of the reachability tree. The algorithm employs multihypothesis search to dynamically explore the v likeliest lowest cost branches of the tree, in order to identify near-optimal DPPs. The cost function incorporates tool changes, changes in direction movement, and individual part characteristics (e.g ...


Determining Optimum And Suboptimum Disassembly Sequences With An Application To A Cell Phone, A.J.D. (Fred) Lambert, Surendra M. Gupta Oct 2010

Determining Optimum And Suboptimum Disassembly Sequences With An Application To A Cell Phone, A.J.D. (Fred) Lambert, Surendra M. Gupta

Surendra M. Gupta

We study the disassembly process of a moderately complex consumer product (cell phone) consisting of 25 components. The investigation involves a heuristically solved disassembly line balancing problem and the determination of an appropriate disassembly sequence influenced by sequence-dependent costs, which is based on a novel combination of exact and heuristic algorithms. The issue of generating various suboptimum solutions to cope with multiple optimization criteria is also discussed.


Design Of An Integrated Component Recovery System, Pitipong Veerakamolmal, Surendra Gupta Oct 2010

Design Of An Integrated Component Recovery System, Pitipong Veerakamolmal, Surendra Gupta

Surendra M. Gupta

This paper presents a two-stage disassembly and retrieval system that provides a unique solution for planning selective component recovery from products. The solution approach uses a process sequencing technique to schedule the operations in both stages to optimize the operational makespan.


Planning An Efficient Closed-Loop Supply Chain Network : A Unified Single Phase Approach, Satish Nukala, Surendra M. Gupta Oct 2010

Planning An Efficient Closed-Loop Supply Chain Network : A Unified Single Phase Approach, Satish Nukala, Surendra M. Gupta

Surendra M. Gupta

No abstract provided.


Efficient Design And Effective Marketing Of A Reverse Supply Chain : A Fuzzy Logic Approach, Kishore K. Pochampally, Surendra M. Gupta Oct 2010

Efficient Design And Effective Marketing Of A Reverse Supply Chain : A Fuzzy Logic Approach, Kishore K. Pochampally, Surendra M. Gupta

Surendra M. Gupta

A two-phase mathematical programming approach to efficiently design a reverse supply chain is proposed, as follows: in phase I, a fuzzy cost-benefit function is formulated to perform a multi-criteria economic analysis for selecting the most economical product to re-process, from a set of candidate used products; in phase II, an integer goal programming model that not only identifies potential recovery facilities but also leads to transportation of the right mix and quantities of products (used as well as re-processed) across the supply chain, is formulated. Since the success of a reverse supply chain depends on its marketing strategy as well ...


A Combinatorial Cost-Benefit Analysis Methodology For Designing Modular Electronic Products For The Environment, Pitipong Veerakamolmal, Surendra Gupta Oct 2010

A Combinatorial Cost-Benefit Analysis Methodology For Designing Modular Electronic Products For The Environment, Pitipong Veerakamolmal, Surendra Gupta

Surendra M. Gupta

This paper presents a technique to analyze the efficiency of designing electronic products for the environment. The efficiency of each design is indicated using a Design for Disassembly Index (DfDI). DfDI uses a disassembly tree (DT) which relies on the product's bill of materials as its structural blueprint. DfDI can be used to compare the efficiency among alternative designs, identifying the best alternative for a product retirement plan. In addition, the index offers designers with an important measure to help improve future products.


Disassembly Petri Net Generation In The Presence Of Xor Precedence Relationships, K. E. Moore, Askiner Gungor, Surendra M. Gupta Oct 2010

Disassembly Petri Net Generation In The Presence Of Xor Precedence Relationships, K. E. Moore, Askiner Gungor, Surendra M. Gupta

Surendra M. Gupta

A disassembly process plan (DPP) is a sequence of disassembly tasks which begins with a product to be disassembled and terminates in a state where all the parts of interest are disconnected. Disassembly process planning is critical for minimizing the resources invested in disassembly and maximizing the level of automation of the disassembly process and the quality of the parts (or materials) recovered. In this paper, we propose an algorithm which automatically generates a disassembly PN (DPN) from a geometrically-based disassembly precedence matrix (DPM). This algorithm can be used to generate DPPs for products which contain simple AND, OR, complex ...


A Multi-Phase Mathematical Programming Approach To Strategic Planning Of An Efficient Reverse Supply Chain Network, Kishore Pochampally, Surendra Gupta Oct 2010

A Multi-Phase Mathematical Programming Approach To Strategic Planning Of An Efficient Reverse Supply Chain Network, Kishore Pochampally, Surendra Gupta

Surendra M. Gupta

Strategic planning of a supply chain network is one of the most challenging aspects of reverse logistics. To effectively satisfy drivers such as profitability, environmental regulations and asset recovery, only the most economical used products must be reprocessed in only the recovery facilities that have the potential to efficiently reprocess them. Due to uncertainties in supply, quality and reprocessing times of used-products, the cost-benefit function in the literature that selects the most economical product to reprocess from a set of used-products is not appropriate for direct adoption. Moreover, due to the same uncertainties, any traditional forward supply chain approach to ...


Disassembly-To-Order System Using Linear Physical Programming, Elif Kongar, Surendra M. Gupta Oct 2010

Disassembly-To-Order System Using Linear Physical Programming, Elif Kongar, Surendra M. Gupta

Surendra M. Gupta

One of the most responsible ways of processing end-of-life (EOL) products is to minimize their disposal to landfills by reusing, remanufacturing and/or recycling them. Often, this necessitates a certain level of disassembly. It is therefore necessary to plan disassembly processing efficiently so as to minimize costs and the amount of disposal as well as to maximize reuse, remanufacturing and recycling. In this paper, we present a disassembly-to-order system to determine the number of EOL products to process to fulfill a certain demand for products, parts and/or materials under a variety of objectives and constraints using a newly developed ...


A Stochastic Inventory Management Approach In The Disassembly Line Portion Of Reverse Logistics, Badr O. Johar, Surendra M. Gupta Sep 2010

A Stochastic Inventory Management Approach In The Disassembly Line Portion Of Reverse Logistics, Badr O. Johar, Surendra M. Gupta

Surendra M. Gupta

Reverse logistics is a critical topic that has captured the attention of government, private entities and researchers in recent years. This increase in the concern was driven by current set of government regulations, increase of public awareness, and the attractive economic opportunities. As a result, many corporations have started to comprehend the importance of the recovery process and are taking serious steps in restructuring their supply chain processes to meet the new regulations such as limitations on waste disposal and recycling requirements [1]. Because of the unique problems associated with reverse supply chain and the complex nature of the reverse ...


System Dynamics Approach In Inventory Management Of End-Of-Life Products In A Disassembly Line, Badr Johar, Surendra Gupta Sep 2010

System Dynamics Approach In Inventory Management Of End-Of-Life Products In A Disassembly Line, Badr Johar, Surendra Gupta

Surendra M. Gupta

A major challenge original equipment manufacturers (OEMs) currently face is how to implement an effective reverse supply chain network that is both cost effective and efficient. The rapid increase in the end-of-life (EOL) products returns from end customers back to origin for recovery or proper disposal can be said one of the main reasons behind this interest. Thus, the purpose of this paper is to examine the relationship between all elements of inventory management in the disassembly context using the system dynamic modeling approach to analyze the inventory of disassembled parts. Analysis of different market scenarios is conducted. The system ...


Dynamic Programming For Solving Disassembly-To-Order System Under Stochastic Yields, Limited Supply, And Quantity Discount, Amre Massoud, Surendra Gupta Sep 2010

Dynamic Programming For Solving Disassembly-To-Order System Under Stochastic Yields, Limited Supply, And Quantity Discount, Amre Massoud, Surendra Gupta

Surendra M. Gupta

In this paper, we consider the disassembly-to-order (DTO) problem where a variety of returned end-of-life (EOL) products are disassembled in order to satisfy the demand for specified numbers of components. However, a lot of uncertainties exist in the disassembly process that further complicates the process. A DTO model has been developed that takes into consideration the different system uncertainties and variability. The DTO model was solved in multiple periods using dynamic programming (DP). The main objective was to determine optimal number of takeback EOL products in every period from each supplier to fulfill the demand of components while maximizing total ...


Analysis Of A Kanban Controlled Disassembly Line With Sensor Embedded Products, Mehmet Ali Ilgin, Surendra M. Gupta Sep 2010

Analysis Of A Kanban Controlled Disassembly Line With Sensor Embedded Products, Mehmet Ali Ilgin, Surendra M. Gupta

Surendra M. Gupta

The use of sensors in the detection of non-functional or missing components in a product before disassembling it is a promising approach to deal with the high level uncertainty associated with disassembly yield. This study presents a quantitative assessment of the impact of the sensor embedded products on the various performance measures of a kanban-controlled disassembly line. First, two separate design of experiments studies based on Orthogonal Arrays are carried out for the cases with and without sensor embedded products. Then, the results of paired-t tests comparing two cases based on different performance measures are presented.


Analysis Of Remanufacturing Policy With Consideration For Returned Products Quality, Kenichi Nakashima, Surendra M. Gupta Sep 2010

Analysis Of Remanufacturing Policy With Consideration For Returned Products Quality, Kenichi Nakashima, Surendra M. Gupta

Surendra M. Gupta

This paper deals with the product acquisition control problem and considers returned product quality with two types of classes. The system includes the flow of the product returns from customers to the factory as well as the forward flow of the sales. We formulate the acquisition problem together with product quality and stochastic demand using the Markov decision process. A numerical example is given to show the implementation of the methodology.


The Effect Of Disassembly Process On Spare Parts Inventory Management In Post Product Life Cycle, Mehmet Ali Ilgin, Surendra M. Gupta Sep 2010

The Effect Of Disassembly Process On Spare Parts Inventory Management In Post Product Life Cycle, Mehmet Ali Ilgin, Surendra M. Gupta

Surendra M. Gupta

Timely and cost-effective acquisition of spare parts at post product life cycle (PPLC) is a challenging task due to limited supply of new spare parts. The most commonly used solution to this problem is the placement of a final order in the beginning of PPLC. Another alternative is the use of disassembled parts from End of Life (EOL) products. In this study, we consider both alternatives at the same time. First, a detailed discrete event simulation (DES) model of a disassembly line is developed. Then, a Genetic Algorithm (GA) is integrated with the DES model for the optimization of Final ...


Disassembly Of Sensor Embedded Products With Component Discriminating Demand, Mehmet Ali Ilgin, Surendra M. Gupta Sep 2010

Disassembly Of Sensor Embedded Products With Component Discriminating Demand, Mehmet Ali Ilgin, Surendra M. Gupta

Surendra M. Gupta

There is a high level uncertainty associated with disassembly yield due to existence of unfunctional and/or unneeded components in end of life products. Sensors embedded in critical components of a product can deal with this uncertainty by providing information on the type and condition of the components prior to disassembly. This study presents a quantitative assessment of the impact of sensor embedded products (SEPs) on the various performance measures of a kanban-controlled washing machine disassembly line. First, separate design of experiments studies based on orthogonal arrays are performed for the cases with and without SEPs. Then, the results of ...


An Evaluation Of The Effect Of Sensor Embedded Products In Product Disassembly With Precedence Relationships, Mehmet Ilgin, Surendra Gupta Sep 2010

An Evaluation Of The Effect Of Sensor Embedded Products In Product Disassembly With Precedence Relationships, Mehmet Ilgin, Surendra Gupta

Surendra M. Gupta

A promising solution approach to deal with the uncertainty associated with disassembly yield is sensor embedded products (SEPs) which involve sensors implanted during the production process. This study presents a quantitative assessment of the impact of SEPs on the various performance measures of a kanban-controlled air conditioner disassembly line. First, separate design of experiments studies based on orthogonal arrays are carried out for the cases with and without SEPs. Then, the results of paired-t tests comparing two cases based on different performance measures are presented.


Linear Physical Programming For Solving The Multi-Criteria Disassembly-To-Order Problem Under Stochastic Yields, Limited Supply, And Quantity Discount, Amre Massoud, Surendra Gupta Sep 2010

Linear Physical Programming For Solving The Multi-Criteria Disassembly-To-Order Problem Under Stochastic Yields, Limited Supply, And Quantity Discount, Amre Massoud, Surendra Gupta

Surendra M. Gupta

This paper focuses on the disassembly-to-order (DTO) problem. End-of-life (EOL) products are purchased from a number of suppliers in order to be disassembled into individual components to satisfy the demand for specified numbers of components. However, there are a lot of uncertainties that complicates the process. Previous work in the literature solved the DTO problem under multiple uncertainties and a single objective. Other models solved the multicriteria DTO problem with a single uncertainty. This paper develops a multi-criteria DTO model that takes into consideration multiple system uncertainties and solves it using Linear Physical Programming (LPP). The main objective was to ...