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2014

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Articles 5461 - 5490 of 7238

Full-Text Articles in Engineering

Environmental Fatigue Of Silicate Glasses In Humid Conditions, Zhongzhi Tang, Richard K. Brow Jan 2014

Environmental Fatigue Of Silicate Glasses In Humid Conditions, Zhongzhi Tang, Richard K. Brow

Materials Science and Engineering Faculty Research & Creative Works

Failure strains of commercial silica, soda-lime-silicate, and E-glass fibers were measured using two-point bending in room temperature humid air. Humidity dependence and dynamic fatigue behavior were studied, and the fatigue reaction orders in terms of humidity were determined. In the humidity range tested (~0.1% to ~100%), the dynamic fatigue parameters for silica and E-glass are found to be greater in lower humidity (~0.1% to ~10%), whereas the fatigue parameter for soda-lime-silicate is independent of humidity. The humidity dependence of failure strains for all three glasses was more pronounced in high humidity (~10% to ~100%) than in low humidity (~0.1% to …

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Rheological Model Of Force Transmission Through The Helmet And Concussion Sensitivity, Isiah Kendall, Anthony Vicini, Tarun Goswami Jan 2014

Rheological Model Of Force Transmission Through The Helmet And Concussion Sensitivity, Isiah Kendall, Anthony Vicini, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

In contact sports, head-to-head collisions can lead to concussions, which pose serious health risks to players. This research aims to understand the force transfer from the helmet to the brain that causes concussions in collisions using a rheological model. Experimental data was gathered from players in the National Football League and testing of one type of helmet and padding. The rheological model was verified with published data and good correlation was achieved. Further sensitivity analysis of concussion risk was performed with respect to force, body weight, mass, and impact duration fit to normal and Weibull distributions using Monte Carlo simulations …

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Rss Based Localization In A Rayleigh Fading Environment, Rojina Adhikary Jan 2014

Rss Based Localization In A Rayleigh Fading Environment, Rojina Adhikary

Electronic Theses and Dissertations

The objective of this thesis is to quantify the improvement that can be obtained in sensor agent localization accuracy as a function of the number of multipath components that can be resolved. We assume that a known number sensor agents are located at unknown coordinates within a rectangular grid having anchors at the corner locations, whose locations are known. Further, we assume fading is Rayleigh and that the propagation constant is constant but unknown. Also, we assume that modulation is spread spectrum and that either the sensors or agents are capable of resolving multipath components down to the chip level …

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Evaluation Of Truck Signal Priority At N Columbia Blvd And Martin Luther King Jr. Blvd Intersection: Vissim Micro Simulation Analysis Of Truck Signal Priority, Maisha Mahmud Jan 2014

Evaluation Of Truck Signal Priority At N Columbia Blvd And Martin Luther King Jr. Blvd Intersection: Vissim Micro Simulation Analysis Of Truck Signal Priority, Maisha Mahmud

Civil and Environmental Engineering Master's Project Reports

Given the importance of over growing freight transportation system worldwide, engineers and planners are faced with the challenge of improving freight service in urban area using low cost measure. Truck Signal Priority is one of the strategy that can be used to improve operational efficiency with enhance safety benefits (red light running) of freight service, without major capital investment. In light to this interest this study focus on evaluating the impacts of freight signal priority on a high truck density intersection like N Columbia Blvd and NE Martin Luther King Jr. Blvd. Using a simulation tool, VISSIM, these impacts were …

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Geospatial Analysis Of Rural Motor Vehicle Traffic Crashes In Oregon, Saad Nayef Almutairi Jan 2014

Geospatial Analysis Of Rural Motor Vehicle Traffic Crashes In Oregon, Saad Nayef Almutairi

Civil and Environmental Engineering Master's Project Reports

This research examines the spatial extent of crashes in and around city boundaries in the state of Oregon in the U.S.A. For this study, a summary of fatalities data for the year 2006 obtained from NHTSA's report (2009), crash data for the year 2012, and city boundaries were obtained from ODOT "Oregon Department of Transportation" FTP: www.odot.state.or.us. In order to differentiate between the urban and rural crashes, city boundaries were used to find the numbers of urban and rural crashes. Outside areas of this urban-rural boundary were divided into further boundaries of 2.5 miles. An intersection tool in ArcMap …

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Adaptive Relay-Selection In Decode-And-Forward Cooperative Systems, Adham Ahmed Hagag Jan 2014

Adaptive Relay-Selection In Decode-And-Forward Cooperative Systems, Adham Ahmed Hagag

Electronic Theses and Dissertations

In the past few years adaptive decode-and-forward cooperative diversity systems have been studied intensively in literature. Many schemes and protocols have been proposed to enhance the performance of the cooperative systems while trying to alleviate its drawbacks. One of the recent schemes that had been shown to give high improvements in performance is the best-relay selection scheme. In the best-relay selection scheme only one relaying nodes among the relays available in the system is selected to forward the source's message to the destination. The best relay is selected as the relay node that can achieve the highest end-to-end signal-to-noise ratio …

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Reconfigurable Microstrip Antennas With Tunable Radiation Pattern Characteristics, Ahmed Khidre Jan 2014

Reconfigurable Microstrip Antennas With Tunable Radiation Pattern Characteristics, Ahmed Khidre

Electronic Theses and Dissertations

Reconfigurable beam antenna systems are capable of changing their radiation characteristics in real time, such as beam direction, beam shape, beamwidth, etc. Such antenna system is desired for various wireless applications because of many reasons among them; it helps to enhance signal strength received from an intended target, mitigates interference, and accommodates sudden changes in traffic demand of wireless networks. It might also help to reduce the deployment cost of wireless networks infrastructures. In this dissertation, designs for reconfigurable beam microstrip antennas with tunable radiation characteristics have been proposed. The method to achieve these designs is the reconfigurable parasitic element …

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The Journal Of Undergraduate Research: Volume 12 Jan 2014

The Journal Of Undergraduate Research: Volume 12

The Journal of Undergraduate Research

This is the complete issue of the South Dakota State University Journal of Undergraduate Research, Volume 12.

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Integration Of A Pulsating Heat Pipe In A Flat Plate Heat Sink, Mitchell Hoesing Jan 2014

Integration Of A Pulsating Heat Pipe In A Flat Plate Heat Sink, Mitchell Hoesing

The Journal of Undergraduate Research

The ongoing development of faster and smaller electronic components has led to a need for new technologies to effectively dissipate waste thermal energy. The pulsating heat pipe (PHP) shows potential to meet this need, due to its high heat flux capacity, simplicity, and low cost. A flat plate PHP was integrated into an aluminum flat plate heat sink with a simulated electronic load. The PHP heat sink used water as the working fluid and had 20 parallel channels with dimensions 2 mm × 2 mm × 119 mm. Experiments were run under various operating conditions, and the thermal resistance of …

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Vibrations Analysis On Tennis Racket String, Jenny Blackburne Jan 2014

Vibrations Analysis On Tennis Racket String, Jenny Blackburne

The Journal of Undergraduate Research

The purpose of this project was to investigate and analyse the vibration of a tennis racket string when a ball is hit. This was done using concepts of mechanical vibrations and modelled using Microsoft Excel. The displacement of the tennis string over time was graphed for two different positions on the racket and two different relative speeds of the tennis ball. It was found that the position of the tennis ball on the racket has very little effect on the displacement of the strings. If the ball or racket is moving faster when the ball is hit, then the displacement …

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Active Infrared Sensing Of Impact Damage In Carbon Fibre Reinforced Polymer, Kwek Tze Tan, Liping Zhao, Shaochun Ye, Tong Kuan Chuah, Pramoda Kumari Pallathadka, Hui Ru Tan Jan 2014

Active Infrared Sensing Of Impact Damage In Carbon Fibre Reinforced Polymer, Kwek Tze Tan, Liping Zhao, Shaochun Ye, Tong Kuan Chuah, Pramoda Kumari Pallathadka, Hui Ru Tan

Mechanical Engineering Faculty Research

With the growing demand of carbon fibre reinforced plastic (CFRP) in aerospace, marine and automobile industries, much attention is devoted to characterizing the material strength and characteristics of failure. This paper demonstrated the feasibility to estimate the internal damage non-destructively as a result of a quantified impact applied on 16-ply fabric CFRP. On thermography images at different heating time, differences were observed between intact area and area with internal damage. The estimation of 1D extent of damage using thermographic analysis was compared with images observed with cross sectional microscopic. The results suggest that qualitative analysis using thermography shows potential to …

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Numerical Evaluation Of The Extended Endplate Moment Connection Subjected To Cyclic Loading, Mehdi Ghassemieh, Mehdi Jalalpour, Ali Akbar Gholampour Jan 2014

Numerical Evaluation Of The Extended Endplate Moment Connection Subjected To Cyclic Loading, Mehdi Ghassemieh, Mehdi Jalalpour, Ali Akbar Gholampour

Civil and Environmental Engineering Faculty Publications

In this paper, the seismic behaviour of extended endplate moment connection is analysed using finite element method (FEM). First, an existing test setup is modelled and analysed using ANSYS computer program. The model is validated by comparing the results from the finite element with the experimental ones. Afterwards, by changing the dimensions of members of the connection, their effect on the overall seismic performance of connection is investigated. The results show that by enlarging the column depth and stiffening the connection, the seismic performance is improved and the thickness of endplate should be chosen in a way that its moment …

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Electromyogram Synergy Control Of A Dexterous Artificial Hand To Unscrew And Screw Objects, Benjamin A. Kent, Nareen Karnati, Erik D. Engeberg Jan 2014

Electromyogram Synergy Control Of A Dexterous Artificial Hand To Unscrew And Screw Objects, Benjamin A. Kent, Nareen Karnati, Erik D. Engeberg

Mechanical Engineering Faculty Research

Due to their limited dexterity, it is currently not possible to use a commercially available prosthetic hand to unscrew or screw objects without using elbow and shoulder movements. For these tasks, prosthetic hands function like a wrench, which is unnatural and limits their use in tight working environments. Results from timed rotational tasks with human subjects demonstrate the clinical need for increased dexterity of prosthetic hands, and a clinically viable solution to this problem is presented for an anthropomorphic artificial hand.

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Behavior Of Hybrid Frp-Concrete-Steel Double-Skin Tubes Subjected To Cyclic Axial Compression, Omar I. Abdelkarim, Mohamed A. Elgawady Jan 2014

Behavior Of Hybrid Frp-Concrete-Steel Double-Skin Tubes Subjected To Cyclic Axial Compression, Omar I. Abdelkarim, Mohamed A. Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents the results of an experimental study that was conducted to investigate the effects of key parameters on the compressive behavior of fiber-reinforced polymer (FRP)-concrete-steel double-skin tubular columns (FSDT). Hybrid FSDT columns have been introduced as a new form of hybrid columns. They consist of an outer tube made of FRP and inner tub made of steel, with sandwiched concrete between them. This paper investigated the effect of fiber angle and the ratio of steel tube diameter to its thickness (Di/ts) on the compressive behavior of FSDT columns. Six FSDT cylinders with different (Di/ts), in addition to two …

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Choice Of Thixotropic Index To Evaluate Formwork Pressure Characteristics Of Self-Consolidating Concrete, Ahmed F. Omran, Kamal H. Khayat Jan 2014

Choice Of Thixotropic Index To Evaluate Formwork Pressure Characteristics Of Self-Consolidating Concrete, Ahmed F. Omran, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Formwork lateral pressure exerted by concrete is affected by mixture composition, placement conditions, and formwork characteristics. The mixture composition includes binder type and content, supplementary cementitious materials, fillers, water-to-cementitious ratio, content and characteristics of coarse aggregate, paste volume, chemical admixtures, concrete unit weight, concrete consistency, and temperature. Thixotropy of concrete expressed here in terms of structural build-up at rest is employed to collectively reflect the effect of combined mix design factors on formwork pressure. This research demonstrates relationships between 12 indices that can be used to evaluate the structural build-up at rest of concrete, determined using portable vane, inclined plane, …

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Four-Dimensional Reflectivity Data Comparison Between Two Ground-Based Radars: Methodology And Statistical Analysis, Bong Chul Seo, Witold F. Krajewski, James A. Smith Jan 2014

Four-Dimensional Reflectivity Data Comparison Between Two Ground-Based Radars: Methodology And Statistical Analysis, Bong Chul Seo, Witold F. Krajewski, James A. Smith

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A methodology is proposed to compare radar reflectivity data obtained from two partially overlapping ground-based radars in order to explain relative differences in radar-rainfall products and establish sound merging procedures for multi-radar observing networks. To identify radar calibration differences, radar reflectivity is compared for well-matched radar sampling volumes viewing common meteorological targets. Temporal separation and three-dimensional matching of two different sampling volumes were considered based on the original polar coordinates of radar observation. Since the proposed method assumes radar beam propagation under standard atmospheric conditions, anomalous propagation cases were eliminated from the analysis. The reflectivity comparison results show systematic differences …

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A Modified Orthogonal Collocation Method For Reaction Diffusion Problems, Moustafa A. Soliman, Yousef S. Al-Zeghayer, Abdelhamid M. Ajbar Jan 2014

A Modified Orthogonal Collocation Method For Reaction Diffusion Problems, Moustafa A. Soliman, Yousef S. Al-Zeghayer, Abdelhamid M. Ajbar

Chemical Engineering

A low-order collocation method is often useful in revealing the main features such as concentration and temperature profiles and the effectiveness factor for porous catalyst particles. Two modifications are introduced in this paper to make the method more efficient. The first modification is to add an extra collocation point at the center of the particle. It is shown that such extra point introduces a single variable non-linear equation to be solved after obtaining the standard collocation method solution. In the second modification, the polynomial solution obtained from the application of the orthogonal collocation method is transformed to a rational function …

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Distributional Fate Of Elements During The Synthesis Of Zeolites From South African Coal Fly Ash, Pieter W. Du Plessis, Tunde V. Ojumu, Ojo O. Fatoba, Richard O. Akinyeye, Leslie F. Petrik Jan 2014

Distributional Fate Of Elements During The Synthesis Of Zeolites From South African Coal Fly Ash, Pieter W. Du Plessis, Tunde V. Ojumu, Ojo O. Fatoba, Richard O. Akinyeye, Leslie F. Petrik

Mining Engineering Faculty Research & Creative Works

The synthesis of zeolites from South African coal fly ash has been deemed a viable solution to the growing economical strain caused by the disposal of ash in the country. Two synthesis routes have been studied thus far namely the 2-step method and the fusion assisted process. Fly ash contains several elements originating from coal which is incorporated in the ash during combustion. It is vital to determine the final destination of these elements in order to unveil optimization opportunities for scale-up purposes. The aim of this study was to perform a material balance study on both synthesis routes to …

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Positioning Automated Guided Vehicles In A General Guide-Path Layout, Abraham Mendoza, Jose A. Ventura Jan 2014

Positioning Automated Guided Vehicles In A General Guide-Path Layout, Abraham Mendoza, Jose A. Ventura

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

The locations of dwell points for idle vehicles in an automated guided vehicle (AGV) system determine the response times for pick-up requests and thus affect the performance of automated manufacturing systems. In this study, we address the problem of optimally locating dwell points for multiple AGVs in general guide-path layouts with the objective of minimizing the maximum response time in the system. We propose a mixed integer linear programming (MILP) formulation for the problem. We also develop a generic genetic algorithm (GA) to find near optimal solutions. The MILP model and GA procedure are illustrated using a two-dimensional grid layout …

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Integrating Analysis Into A Warehouse Design Workflow, Leon Mcginnis, Timothy Sprock Jan 2014

Integrating Analysis Into A Warehouse Design Workflow, Leon Mcginnis, Timothy Sprock

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Supply chain analyses, including those related to material handling systems, are typically purpose-built to answer specific questions and therefore have many different implementations depending on the question, the instance data, and the solver. The purpose-built nature of these models makes it difficult to integrate them into an iterative design workflow. Despite the myriad analysis implementations, the fundamental structure of these systems and their problem domain remains unchanged, suggesting that perhaps analyses could be automatically generated on demand, given an appropriate specification of the particular system to be analyzed. We apply model-based systems engineering (MBSE) methodologies to explore this possibility in …

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Throughput Analysis Of S/R Shuttle Systems, Georg Kartnig, Jörg Oser Jan 2014

Throughput Analysis Of S/R Shuttle Systems, Georg Kartnig, Jörg Oser

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Shuttle systems are used in high performance automated storage/retrieval unit load systems. Each storage level is serviced by one transfer car travelling in dual command operation. One buffer slot is located at both ends of each level. This decouples horizontal travel from vertical input/output moves, which in this case requires two independent vertical reciprocating lifts at each end of the aisle. Other systems work with only one lift used in lower throughput applications. The content of this paper is treated in the following sections starting with a problem definition and a literature survey. This is followed by a detailed functional …

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Variation In Lifting Behavior During A Highly Repetitive Manual Material Task, Steven A. Lavender Jan 2014

Variation In Lifting Behavior During A Highly Repetitive Manual Material Task, Steven A. Lavender

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Presenters will provide.

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Clickstream Big Data And “Delivery Before Order Making” Mode For Online Retailers, Yeming Yale Gong, Haoxuan Xu Jan 2014

Clickstream Big Data And “Delivery Before Order Making” Mode For Online Retailers, Yeming Yale Gong, Haoxuan Xu

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Our research is inspired by a leading online retailer using clickstream big data to estimate customer demand and then ship items to customers or hubs near customers by a mode of “delivery before order making” (DBOM) mode. Using clickstream data to obtain advance demand information in order quantities, we integrate the forecasting with a singleitem uncapacitated dynamic lot sizing problem in a rolling-horizon environment. Using the simulated clickstream data, we evaluate the performance of DBOM mode.

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Comparing Industry And Academic Perspectives On Cross-Docking Operations, Paul Buijs, Iris F.A. Vis Jan 2014

Comparing Industry And Academic Perspectives On Cross-Docking Operations, Paul Buijs, Iris F.A. Vis

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

This paper performs a comparative analysis on the industry and academic perspectives on cross-docking operations. Detailed descriptions are provided for three typical cross-dock settings by means of case illustrations. The purpose of these descriptions is to inspire break-through innovations in future cross-docking research by identifying constraints, decision problems, and performance indicators that are thoroughly anchored in current practice.

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Comparison Of Alternative Configurations For Dense Warehousing Systems, Kevin R. Gue, G. Don Taylor Jan 2014

Comparison Of Alternative Configurations For Dense Warehousing Systems, Kevin R. Gue, G. Don Taylor

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

In heavily constrained environments requiring very high density storage, traditional aisle-based warehousing may not provide viable options. One feasible manifestation of high density storage systems is the ‘puzzle-based’ system, in which unit loads are moved through the system via manipulation of empty (escort) locations to retrieve desired items. Another option would be the use of movable concentric rings, with escorts being utilized to enable lateral movements of unit loads between the rings. In this paper, the authors present analytical results to compare retrieval time performance for these two types of high density storage systems for randomly demanded items under various …

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Analysis Of Class-Based Storage Strategies For The Mobile Shelf-Based Order Pick System, Shobhit Nigam, Debjit Roy, Rene De Koster, Ivo J.B.F. Adan Jan 2014

Analysis Of Class-Based Storage Strategies For The Mobile Shelf-Based Order Pick System, Shobhit Nigam, Debjit Roy, Rene De Koster, Ivo J.B.F. Adan

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Mobile Shelf-based Order Pick (MSOP) systems are gaining significant in- terest for e-commerce fulfillment due to their rapid deployment capability and dynamic organization of storage pods based on item demand profiles. In this research, we model the MSOP system with class-based storage strategies and alternate pod storage policies using multi-class closed queuing networks. We observe that though closest-open location pod storage policy do not allow to efficiently use the storage spaces in comparison to random location pod storage policy in an aisle, it increases the system throughput for all item classes.

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A Two-Level Stochastic Model To Estimate Vessel Throughput Time, Debjit Roy, Vibhuti Dhingra, Rene De Koster Jan 2014

A Two-Level Stochastic Model To Estimate Vessel Throughput Time, Debjit Roy, Vibhuti Dhingra, Rene De Koster

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

A good estimate of the vessel sojourn time is essential for better planning and scheduling Of container terminal resources,such as berth scheduling,quay crane(qc)assignment And scheduling,and fleet size planning. However,estimating the expected vessel so journ Time is a complex exercise because the time is dependent on several terminal operating Parameters such as the size of the vessel,the number of containers to be loaded and Unloaded,and the through put of the qcs. The through put of the qcs in turn depends On the type and number of transport vehicles,number of stack blocks,the topology of The vehicle travel path,the layout of the terminal,and …

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An Empirical Study About The Effectiveness Of Lean Empowerment In Warehouses, Kai Furmans, Payam Dehdari Jan 2014

An Empirical Study About The Effectiveness Of Lean Empowerment In Warehouses, Kai Furmans, Payam Dehdari

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Lean Management is well established in production environments. Some empirical evidences are available which suggest that in production systems lean management achieves positive results. For warehousing, some works have already been done, which deal with the application and adaption of lean tools for usage in warehousing. In order to answer the question, whether the application of lean tools leads to a better performance however, no study is available today. Therefore, an empirical study has been conducted, where the effectiveness of lean empowerment has been tested and compared to the performance of warehouse, who continued to work as before.

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Performance Comparison Of Various Order Picking Methods In Different Behavioral Contexts, Jelle De Vries, Rene De Koster, Daan Stam Jan 2014

Performance Comparison Of Various Order Picking Methods In Different Behavioral Contexts, Jelle De Vries, Rene De Koster, Daan Stam

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

Three manual picker-to-parts order picking methods (parallel picking, zone picking, and dynamic zone picking) are employed in an experimental warehouse setup and compared in terms of productivity, quality, and job satisfaction. Participants worked in teams and were subject to either an individual- based, or a team-based incentive scheme. Furthermore, the influence of individual participants’ dominant regulatory focus (promotion or prevention) was taken into account. The outcomes show that in parallel picking an incentive system focused on individual performance is beneficial for productivity and quality compared to an incentive system focused on team performance, whereas team-based incentives are more productive in …

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A Framework For The Robust Design Of Unit Load Storage Systems, Marc Goetschalckx, Edward Huang, Pratik Mital Jan 2014

A Framework For The Robust Design Of Unit Load Storage Systems, Marc Goetschalckx, Edward Huang, Pratik Mital

13th IMHRC Proceedings (Cincinnati, Ohio. USA – 2014)

The unit load storage assignment problem determines the assignment of a set of unit loads with known arrival and departure times to a set of unit storage locations in a warehouse. The material handling device(s) can carry at most one unit load at the time. In this research it is assumed that each of the storage locations can be accessed directly without load relocations or rearrangements and that the travel times between the storage locations and from and to the warehousing docks can be computed in advance. The objective is to minimize the total travel time of the material handling …

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