Mechanical Engineering Commons^™

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 voltage (DWV), Δ C not …

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 presence of two in‐plane resonance lines and spin‐wave spectra …

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

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

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 magnetization, and linewidth. Well …

Phonon Wave-Packet Simulations Of Ar/Kr Interfaces For Thermalrectification, Nick A. Roberts, D. G. Walker

Nick Roberts

The frequency and direction dependence of transmission coefficients at interfaces was investigated theoretically. The interfaces are formed by having two Lennard-Jones materials differing in mass and interatomic potential equally divided at the center of an fcc lattice system. A single frequency wave-packet is generated at one end of the system and allowed to propagate through the system until all interactions with the interface are complete. The transmission coefficient is then calculated by comparing the energy of the packet that is transmitted with the original wave-packet. Results show a difference in transmission when the wave-packet originates from opposite sides.

15 - معيارهاي نوين طراحي سيستمهاي سرمايش و گرمايش در ساختمانها بر مبناي ايجاد شرايط آسايش حرارتي, Alireza Zolfaghari, Mehdi Maerefat

Dr Alireza Zolfaghari

No abstract provided.

Gas Turbine, Vijaya Krushna Varma Mr

VIJAYA KRUSHNA VARMA Mr

Varma designed ultra modern and high efficiency turbines which can use gas, steam or fuels as feed to produce electricity or mechanical work for wide range of usages and applications in industries or at work sites. Varma turbine engines can be used in all types of vehicles. These turbines can also be used in aircraft, ships, battle tanks, dredgers, mining equipment, earth moving machines etc, Salient features of Varma Turbines. 1. Varma turbines are simple in design, easy to manufacture, easy to operate and maintain. 2. Varma turbines are less expensive. 3. Varma turbines have a great power to weight …

Water Turbine, Vijaya Krushna Varma Mr

VIJAYA KRUSHNA VARMA Mr

Varma designed ultra modern and high efficiency turbines which can use gas, steam or fuels as feed to produce electricity or mechanical work for wide range of usages and applications in industries or at work sites. Varma turbine engines can be used in all types of vehicles. These turbines can also be used in aircraft, ships, battle tanks, dredgers, mining equipment, earth moving machines etc, Salient features of Varma Turbines. 1. Varma turbines are simple in design, easy to manufacture, easy to operate and maintain. 2. Varma turbines are less expensive. 3. Varma turbines have a great power to weight …

14 - تخمين نرخ تهويه ي‌ بهينه براي کيفيت مناسب هواي داخل با توجه به نرخ نفوذ هوا و عملکرد وسايل احتراقي, Chamran Nowrouzi, Mehdi Maerefat, Alireza Zolfaghari

Dr Alireza Zolfaghari

No abstract provided.

1- Thermal Response Of Cutaneous Thermoreceptors: A New Criterion For The Human Body Thermal Sensation, Alireza Zolfaghari, Mehdi Maerefat

Dr Alireza Zolfaghari

No abstract provided.

13 - جانمايي مناسب وسايل احتراقي؛ راهکاري در جهت بهبود کيفيت هواي داخل, Chamran Nowrouzi, Mehdi Maerefat, Alireza Zolfaghari

Dr Alireza Zolfaghari

No abstract provided.

Tunable Band Gaps In Bilayer Graphene-Bn Heterostructures, Ashwin Ramasubramaniam, Doron Naveh, Elias Towe

Ashwin Ramasubramaniam

Bridging The Gap Between The Industrial Environment And The Classroom Via Project-Based Learning, Michael W. Martin

Michael W Martin

Recent engineering education research has concluded that most engineering curricula do not promote attainment of many characteristics desired in practicing engineers. Methods to attain these characteristics include both project-based learning (PBL) and simulation of workplace situations in the educational environment. The presenter will outline the use of both PBL and workplace simulation through the implementation of a semester-long project in a senior-level Data Acquisition course taught out of the Department of Engineering Technology at Northern Michigan University. A typical undergraduate experimental analysis or data acquisition course will review topics including; sensoring, hardware requirements, testing techniques, computer integration, software use, and …

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

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

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 …

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

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

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., hazardous). …

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.

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

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 …

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 …

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 decision tool, …

Structural And Mechanical Properties Of Nanostructured Tio2 Thin Films Deposited By Rf Sputtering

A.S. Md Abdul Haseeb

This study mainly aims to evaluate the effects of substrate temperatures on the mechanical properties of TiO2 thin films deposited on glass substrates by radio-frequency (RF) magnetron sputtering. All titania films possess anatase structure having a nodular morphology. AES results reveal that Si and Na ions from glass diffuse into TiO2 films at higher substrate temperatures. Micro-scratch and wear tests were conducted to evaluate their mechanical and tribological properties. The adhesion critical loads of TiO2 films deposited at room temperature, 200 and 300°C are found to be 1.51, 1.54 and 1.08N, respectively. Scratch hardness also increases from 11.5 to 13.6GPa …

Do Surfaces With Mixed Hydrophilic And Hydrophobic Areas Enhance Pool Boiling?, Amy Rachel Betz, Jie Xu, Huihe Qiu, Daniel Attinger

Daniel Attinger

We demonstrate that smooth and flat surfaces combining hydrophilic and hydrophobicpatterns improve pool boiling performance. Compared to a hydrophilicsurface with 7° wetting angle, the measured critical heat flux and heat transfer coefficients of the enhanced surfaces are, up to respectively, 65% and 100% higher. Different networks combining hydrophilic and hydrophobic regions are characterized. While all tested networks enhance the heat transfer coefficient, large enhancements of critical heat flux are typically found for hydrophilic networks featuring hydrophobic islands. Hydrophilic networks indeed are shown to prevent the formation of an insulating vapor layer.

The Quality Of Life In Our City, B Bakhtyar

B Bakhtyar

Smart Growth (SG) development entails retracting the city; hence, it aims to house low-income residents at new affordable housing facilities within a metropolitan area. On the other hand, the dense living conditions would cause land price to surge due to the scarcity of available land. In this situation, housing developers would be more burdened by high land costs and the low-income families have no alternatives than pay high rental prices to building owners. This research comprises of constructs developed from selected literature review on Smart Growth concept and criteria of importance in meeting the Affordable Quality Housing standards (QOL indicators). …

Comparative Corrosive Characteristics Of Petroleum Diesel And Palm Biodiesel For Automotive Materials

A.S. Md Abdul Haseeb

Corrosive characteristics of biodiesel are important for long term durability of engine parts. The present study aims to compare the corrosion behavior of aluminum, copper and stainless steel in both petroleum diesel and palm biodiesel. Immersion tests in biodiesel (B100) and diesel (B0) were carried out at 80 °C for 1200 h. At the end of the test, corrosion characteristic was investigated by weight loss measurements and changes on the exposed metal surface. Surface morphology was examined by optical microscope and scanning electron microscopy with energy dispersive X-ray analysis (SEM/EDS). Fuels were analyzed by using TAN analyzer, FTIR, GCMS and …

Compatibility Of Elastomers In Palm Biodiesel

A.S. Md Abdul Haseeb

In recent time, environmental awareness and concern over the rapid exhaustion of fossil fuels have led to an increased popularity of biodiesel as an alternative fuel for automobiles. However, there are concerns over enhanced degradation of automotive materials in biodiesel. The present study aims to investigate the impact of palm biodiesel on the degradation behavior of elastomers such as nitrile rubber (NBR), polychloroprene, and fluoro-viton A. Static immersion tests in B0 (diesel), B10 (10% biodiesel in diesel), B100 (biodiesel) were carried out at room temperature (25 °C) and at 50 °C for 500 h. At the end of immersion test, …