Engineering Commons^™

Evaluating The Effect Of Operational Conditions And Practices On Warehouse Performance, Andrew L. Johnson

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Analyzing warehouse performance across different environments is critical to improving overall productivity and reducing costs. Although two-stage DEA estimators have been shown to be statistically consistent, the finite sample bias of DEA in the first stage carries over to the secondstage regression, which causes bias in the estimated coefficients of the contextual variables. The bias is particularly severe when the contextual variables are correlated with inputs. To address this shortcoming, we apply insights from Johnson and Kuosmanen (2010), who demonstrate that DEA can be formulated as a constrained special case of the Convex Nonparametric Least Squares (CNLS) regression to develop …

Comparing Transport Policies In A Full-Scale 300mm Wafer Manufacturing Facility, J. E. Kiba, S. Dauz`Ere-P´Er`Es, C. Yugma, G. Lamiable

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Research in semiconductor manufacturing ideally wants to determine the “best” transport policy to ensure continuous production. Determining such a policy is difficult because it depends on many factors such as the layout, the product types, the equipment, etc. Most of the transport policies found in the literature combine dispatching policies (scheduling of transport requests) and routing policies (selection of the path to move from one point to another). This paper investigates a policy called "minimum service" which consists in keeping a minimum number of available vehicles in bays, so that they can quickly answer transport requests and empty travel times …

The Human-Centric Warehouse, Kevin R. Gue

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

In theory and in practice, the objective of warehouse design has long been to meet operational requirements of throughput and service performance at minimum cost. A natural product of this “bottom line” approach has been warehouse buildings and operations ill-suited to the humans who spend their working lives interacting with them. We offer an explanation for the current approach, and argue that a new approach— a new paradigm —is needed. We then describe a comprehensive approach to warehouse design that includes human well-being as a primary goal.

Forklift Routing In Warehouses Using Dual-Commands And Stackable Pallets, Ahmed Hassan, Bill Ferrell

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

This research determines time optimal routes for loading and picking pallets that can be stacked on top of each other during transport in a manual warehouse that only contains full pallets and utilizes single deep storage. This research was motivated by the fact that we are seeing this situation on an ever increasing basis, particularly in warehouses that supply parts to automotive assembly. In practice, forklift drivers have developed strategies to take advantage of this opportunity but to our knowledge there is no literature that addresses this problem rigorously. The important features of this work are that a time based …

Plug-And-Work Material Handling Systems, Kai Furmans, Frank Schonung, Kevin R. Gue

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

One disadvantage of automated material handling systems is their relative Inflexibility: once racks are installed and conveyors are laid, making even mi-nor changes to a system can be cumbersome and expensive. However, recent progress in the capabilities and cost of basic system components, such as controllers, drives, and sensors, has made possible a new class of material handling systems having a much higher degree of flexibility. We propose underlying de- sign principles for such systems and describe several prototype plug-and-work" systems, which feature decentralized control and ease of reconfiguration.

Control Policies For A Dynamic Storage System With Multiple Lifts And Shuttles, Iris F.A. Vis, Hector J. Carlo, Paloma Diaz, Maria E. Laboy, Bruno Vanwijgaarden

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

New types of Automated Storage and Retrieval Systems, able to achieve high throughput levels, are continuously being developed and require new control polices to take full advantage of the developed system. In this paper we study a dynamic storage system as developed by Vanderlande Industries consisting of a conveyor, two lifts, multiple transfer shuttles, and a storage rack. One of the decision problems for this system is the scheduling problem of the two lifts. In other words, which lift is going to handle which request and in which order. In this paper, we derive an integrated look-ahead heuristic based on …

On Coalgebras Over Algebras, Adriana Balan, Alexander Kurz

Engineering Faculty Articles and Research

We extend Barr’s well-known characterization of the final coalgebra of a Set-endofunctor as the completion of its initial algebra to the Eilenberg-Moore category of algebras for a Set-monad M for functors arising as liftings. As an application we introduce the notion of commuting pair of endofunctors with respect to the monad M and show that under reasonable assumptions, the final coalgebra of one of the endofunctors involved can be obtained as the free algebra generated by the initial algebra of the other endofunctor.

Families Of Symmetries As Efficient Models Of Resource Binding, Vincenzo Ciancia, Alexander Kurz, Ugo Montanari

Engineering Faculty Articles and Research

Calculi that feature resource-allocating constructs (e.g. the pi-calculus or the fusion calculus) require special kinds of models. The best-known ones are presheaves and nominal sets. But named sets have the advantage of being finite in a wide range of cases where the other two are infinite. The three models are equivalent. Finiteness of named sets is strictly related to the notion of finite support in nominal sets and the corresponding presheaves. We show that named sets are generalisd by the categorical model of families, that is, free coproduct completions, indexed by symmetries, and explain how locality of interfaces gives good …

Algebraic Theories Over Nominal Sets, Alexander Kurz, Daniela Petrişan, Jiří Velebil

Engineering Faculty Articles and Research

We investigate the foundations of a theory of algebraic data types with variable binding inside classical universal algebra. In the first part, a category-theoretic study of monads over the nominal sets of Gabbay and Pitts leads us to introduce new notions of finitary based monads and uniform monads. In a second part we spell out these notions in the language of universal algebra, show how to recover the logics of Gabbay-Mathijssen and Clouston-Pitts, and apply classical results from universal algebra.

Isolation And Characterization Of Bacteria From Extended Aeration Wastewater Treatment Plants., Randy Chin Kok Fei

Student Works (2010-2019)

In this study, three different wastewater treatment plants (STP1, STP2 and STP3) were sampled in Klang Valley. STP1 exhibited the best activated sludge health with healthy Sludge Volume (SV), Mixed Liquor Suspended Solids (MLSS) and Mixed Liquor Volatile Suspended Solids (MLVSS). STP2 were constantly disrupted by the mechanical failures which caused its dissolved oxygen (DO) to decrease whereas STP3 was troubled by the inadequate alkalinity in its mixed liquor causing acidic condition in aeration tank. The acidic condition resulted in pin-floc problem and contributed to high Total Suspended Solids (TSS) and low SV. Influent at STP3 was also found to …

A Comparison Of Hemodynamic Performance In Mehcanical And Biological Heart Valve Prostheses, Philip Mathew

Masters Theses and Doctoral Dissertations

Heart valve prostheses are used to replace heart valves in patients afflicted with valvular heart disease. The malfunctioning heart valve adversely affects the fluid mechanical performance. While the choice of mechanical VS biological valve prostheses is dependent on the patient, the biological valves should have improved hemodynamic performance compared to the mechanical valves. This work focused on CFD analysis of the Starr-Edwards caged ball valve and a biological valve and serves to validate the improved hemodynamics of the latter valve in comparison to the former. Commercial CFD software (CFD-GEOM, CFD-ACE, CFD-VIEW) are used for the analys is. The main results …

A Framework To Develop Lifelong Learning And Transferable Skills In An Engineering Programme, Gavin Duffy, Brian Bowe

Conference papers

Engineering programmes have a strong reputation in the delivery of technical knowledge and skills. Graduates need equally high levels of competence in personal and professional skills to not only meet the existing requirements of employers and professional bodies but to also help them manage the inevitable changes that society is facing in an increasingly populated world. The need to move from traditional to student-centred learning is discussed in the context of engineering education. The use of group-based, problem driven learning facilitates high integration of technical and non-technical knowledge and skills and requires more engagement with the programme from today’s student. …

Experiences Of Assessment Using Multiple Choice Questions On Advanced Modules Taken By Level 8 And Level 9 Engineering Students, Aidan O'Dwyer

Conference papers

This contribution evaluates the use of multiple-choice questions, in both formative and summative assessment modes, on advanced modules taken by Level 8 and Level 9 engineering students, over the past two academic years. Assessment data, and student experiences with the assessment methods, are reported and analysed.

E-Fraud Prevention Based On The Self-Authentication Of E-Documents, Jonathan Blackledge, Eugene Coyle

Conference papers

We consider a method for preventing e-Fraud in which a binary image is encrypted with a floating point cipher using a convolution operation and the output quantized into a 1-bit array generating a binary image ciphertext. The output is then ‘embedded’ in a host image to hide the encrypted information. Embedding is undertaken either in the lowest 1-bit layer or multiple 1-bit layers. Decryption is accomplished by: (i) extracting the binary image from the host image; (ii) correlating the result with the original cipher. In principle, any cipher generator can be used for this purpose and the method has been …

Authentication Of Biometric Features Using Texture Coding For Id Cards, Jonathan Blackledge, Eugene Coyle

Conference papers

The use of image based information exchange has grown rapidly over the years in terms of both e-to-e image storage and transmission and in terms of maintaining paper documents in electronic form. Further, with the dramatic improvements in the quality of COTS (Commercial-Off-The-Shelf) printing and scanning devices, the ability to counterfeit electronic and printed documents has become a widespread problem. Consequently, there has been an increasing demand to develop digital watermarking techniques which can be applied to both electronic and printed images (and documents) that can be authenticated, prevent unauthorized copying of their content and, in the case of printed …

Estimating The Yield Of Micro Wind Turbines In An Urban Environment: A Methodology, Keith Sunderland, Michael Conlon

Conference papers

Micro wind turbines currently have the majority share of micro (electricity) generation installations in Ireland. These technologies are being installed predominantly in rural environments, and current applications to the Distribution Services Operator (DSO) for connection of all types of micro generator stand at less than 500. Poor market dissemination of information and research findings compounded with poor options for spill payment - as well as onerous planning restrictions do not –it appears - create a platform conducive to encouraging development in this market.

This paper outlines the complexities associated with evaluating the wind resource within an urban environment and investigates …

Variability In Resilient Modulus Of Reclaimed Asphalt Pavement As Base Layer And Its Impact On Flexible Pavement Performance, Mohamed Attia, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The use of reclaimed asphalt pavement (RAP) as a base layer is gaining popularity, but there are gaps in the literature about its material performance. One problem not well investigated is the variability in the resilient modulus (M_R) of RAP as a base layer, as compared with typical granular material, and the impact of this variability on pavement performance. Selection of one M_R value has its own variability, beyond the expected variability in the base layer _R that results from the use of aggregates with different qualities. This paper investigates the effect of three sources of variability …

Effect Of Radar-Rainfall Uncertainties On The Spatial Characterization Of Rainfall Events, Pradeep V. Mandapaka, Gabriele Villarini, Bong Chul Seo, Witold F. Krajewski

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Remotely sensed precipitation products, due to their large areal coverage and high resolution, have been widely used to provide information on the spatiotemporal structure of rainfall. However, it is well known that these precipitation products also suffer from large uncertainties that originate from various sources. In this study, we selected radar-rainfall (RR) data corresponding to 10 warm season events over a 256 x 256 km² domain with a data resolution of 4 x 4 km² in space and 1 h in time. We characterized their spatial structure using correlation function, power spectrum, and moment scaling function. We then …

Bridge Lessons Learned From The Wenchuan China, Earthquake, W. Phillip Yen, Genda Chen, Mark Yashinski, Youssef M. A. Hashash, Curtis J. Holub, Kehai Wang, Xiaodong Guo

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A strong earthquake of M7.9 occurred in Wenchuan County in Sichuan Province, China, on May 12, 2008. This paper presents the field observations on various types of bridge damages, including unseating of girders, longitudinal and transverse offset of decks, pounding at expansion joints, shear key failure, bearing displacement, column shear, and flexible cracks. Plausible causes of damages and collapses are discussed and the lessons learned from this event are briefly summarized. Some of the postearthquake temporary constructions are also reported.

Digital Human Models Of People With Disabilities, Ron Hamameh

Wayne State University Theses

The current state-of-the-art in Digital Human Modeling (DHM) allows for full simulation and analysis of any task a person is required to perform at home, at work, in the military, in space, in sports, etc. The problem is that the software is missing a very important population: people with physical disabilities. What modifications and enhancements must be made to existing, commercially available DHM software to include this population?

Electro-Optic And Magneto-Dielectric Properties Of Multifunctional Nitride And Oxide Materials, Ambesh Dixit

Wayne State University Dissertations

ABSTRACT

Materials that simultaneously exhibit different physical properties provide a rich area of research leading to the development of new devices. For example, materials having a strong coupling between charge and spin degrees of freedom are essential to realizing a new class of devices referred to generally as spintronics. However, these multifunctional systems pose new scientific challenges in understanding the origin and mechanisms for cross-control of different functionalities. The core of this Ph.D. dissertation deals with multifunctional nitride and oxide compound semiconductors as well as multiferroic magnetic oxide systems by investigating structural, optical, electrical, magnetic, magnetodielectric and magnetoelectric properties.

Thin …

Wired For War: The Robotics Revolution And Conflict In The Twenty-First Century, Frank Rosenblatt

Journal Articles

Pity the librarian who receives a copy of P.W. Singer's Wired for War and must decide where to put it. Since the book wrestles with the changing nature of warfare, it could fit in with other books on war and military affairs. It may also belong in the science fiction section, since it is largely a tribute to the vision of science fiction writers such as Isaac Asimov. Perhaps Wired for War should go alongside works by other futurist thinkers such as George Orwell and Freeman Dyson. Is it really an ethics book? A science text? Strong arguments could be …

Fault Testing Quantum Switching Circuits, Marek Perkowski, Jacob Biamonte

Electrical and Computer Engineering Faculty Publications and Presentations

Test pattern generation is an electronic design automation tool that attempts to find an input (or test) sequence that, when applied to a digital circuit, enables one to distinguish between the correct circuit behavior and the faulty behavior caused by particular faults. The effectiveness of this classical method is measured by the fault coverage achieved for the fault model and the number of generated vectors, which should be directly proportional to test application time. This work address the quantum process validation problem by considering the quantum mechanical adaptation of test pattern generation methods used to test classical circuits. We found …

Importance Of The Tail In Truck Weight Modeling For Bridge Assessment, Eugene J. Obrien, Bernard Enright, Abraham Getachew

Articles

To predict characteristic extreme traffic load effects, simulations are sometimes performed of bridge loading events. To generalize the truck weight data, statistical distributions are fitted to histograms of weight measurements. This paper is based on extensive WIM measurements from two European sites and shows the sensitivity of the characteristic traffic load effects to the fitting process. A semi-parametric fitting procedure is proposed: direct use of the measured histogram where there are sufficient data for this to be reliable and parametric fitting to a statistical distribution in the tail region where there are less data. Calculated characteristic load effects are shown …

An Investigation On Pulsing Performance Of Mn Class Bi-Propellant Thrusters, Carlos Francisco Gomez

Open Access Theses & Dissertations

With the advancement of technology and machining methods, considerable attention has been focused in manufacturing micro thrusters for micro spacecraft applications (Yetter et al, 2003). Micro propulsion systems are currently being investigated for Miniature Kill Vehicles (MKV) and Micro Satellite Systems (MSS) with an emphasis in reducing weight and cost but without affecting performance. Reducing the weight seems practical when reducing the size of the propulsion system, but problems are encountered with system design.

In addition, propulsion requirements strongly influence choice in propellant and complexity. A thorough understanding of stabilizing thrust levels and the ability to control the propulsion system …

Observer-Dependent Model For Analyzing Subjective Parameters In Epidemiology, Milad Zarei

Open Access Theses & Dissertations

Although medical technologies for preventing the contagion and spread of infectious diseases have improved steadily throughout the last century, new infectious diseases are still emerging and spreading swiftly. The modeling of infectious disease spread is crucial in addressing the lack of predictive ability in epidemiology. Managing the spread of infectious diseases requires processing quantitative epidemiological data and the ability to capture the dynamics of the infectious disease in order to provide a measure of control.

In this thesis, I have introducing cognitive biases in diseases spread modeling. For the first time, to the author's knowledge, the human subjective experience has …

A Subthreshold Reconfigurable Architecture For Harsh Environments, Ameet Chavan

Open Access Theses & Dissertations

Energy harvesting and functional reconfigurability are necessary features in order to simultaneously achieve longer operating lifetimes and versatility in application for many next generation electronic systems. The presented research incorporates capabilities that not only enable applications to self-power from ambience but also permit change in functionality based on real-time application requirements. Currently, many applications are battery powered with custom hardware, which severely confines the application platform. Moreover, maintenance and upgrades are prohibitively expensive, particularly in the case of remote locations with limited accessibility. For harsh environments like Space or the battlefield, apart from features such as low power and reconfigurability, …

Engineering Design Educational Model: From Skills To Objectives, Jose Gabriel Davila Rangel

Open Access Theses & Dissertations

The objective of this thesis is to develop an engineering design educational pedagogy on how to improve the engineering design learning experience. The design engineering activity is a complex mix of skills and knowledge that has been taught over decades by directly delivering to the students the design methodologies developed by design researchers and by exposing the students to open ended projects that could develop their design skills. Understanding this we can conclude that the three main pedagogical components of a successful educational design experience are: the design skills, the design methods and the design projects. On one hand, the …

A Tool To Improve And Preserve Flexible Pavement At Intersections, Carlos Jesus Solis

Open Access Theses & Dissertations

Rural intersections originally constructed with thin untreated flexible base and hot mix or a two-course surface treatment tend to experience severe pushing, shoving and rutting. These failures cause an extremely rough surface that can cause damage to small vehicles and potentially cause motorists to lose control of their vehicles. These distresses almost always result in complete failure of the existing pavement that must be repaired several times during the life of the roadway by maintenance forces. In most cases, pavements constructed with the same materials and cross-sections adjacent to the intersection perform adequately.

The sources of and solutions for failure …

Acoustic Reflectometry Using Gaussian-Modulated Sinusoidal Waves And The Ware-Aki Algorithm, Ernesto Rodrigo Vazquez Ceron

Open Access Theses & Dissertations

Acoustic reflectometry, a non invasive technique, consists of solving, the inverse problem of estimating the cross sectional area as function of the distance of a cylindrical cavity by impacting an audible acoustic pulse of high amplitude and short duration, and analyzing the reflected wave. The technique has been applied in Biomedical Engineering to estimate both the area of a human upper airway and the patency of endotracheal tubes as a function of distance. Several ways have been tested to improve the quality of an acoustic pulse and different algorithms have been tested to reduce the losses. However, an acoustic pulse …