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Graduate Theses, Dissertations, and Problem Reports (ETD)

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Highway Cost-Benefit Analysis System, Venkatramani Rajamohan Aug 1999

Highway Cost-Benefit Analysis System, Venkatramani Rajamohan

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this research, a methodology for computing road user cost for various competing alternatives was developed. Also, a software was developed to calculate the road user cost, perform economic analysis and update cost tables. The methodology is based on the manual entitled "A Manual on User Benefit Analysis of Highway and Bus-Transit Improvements" which was published in 1977 by American Association of State Highway and Transportation Officials. The report contains procedures for the calculation of the road user cost, perform economic analysis and further update the cost tables as and when the latest Consumer Price Indices and Producer Price Indices …

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Perceptions Of Students And Teachers Regarding Agriculture In Leflore County, Mississippi, Ronald L. Howard Aug 1999

Perceptions Of Students And Teachers Regarding Agriculture In Leflore County, Mississippi, Ronald L. Howard

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to assess the perceptions of public high school teachers and students in Leflore County, Mississippi regarding agriculture and provide baseline data regarding the perception of high school students and teachers residing in an agriculturally dependent county with no agricultural education program. A population of 240 high school teachers and students was surveyed for their perceptions regarding agriculture. All three public high schools in Leflore County were represented in this study. Over 65% of the sample resided in the city, while only 3% live on a farm. The major finding of this study was that …

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Durability And Mode-I Fracture Of Fiber-Reinforced Plastic (Frp)/Wood Interface Bond, Brent Stephen Trimble Aug 1999

Durability And Mode-I Fracture Of Fiber-Reinforced Plastic (Frp)/Wood Interface Bond, Brent Stephen Trimble

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fiber-reinforced plastic (FRP) composites are being used for reinforcement of wood, concrete, and steel. The objective of this study is to develop a qualification program to evaluate the service performance and fracture of composite/wood bonded interfaces. The proposed method is used for two types of FRP wood interface: FRP strips (plates) bonded to wood (used commercially for glulam timber beams) and wood cores wrapped with FRP by filament winding (being investigated for reinforced railroad wood crossties and utility wood poles). First, the service performance and durability of FRP-wood interface bond is evaluated using a modified ASTM delamination test. Second, the …

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Automatic Type Curve Matching For Predicting Gas Wells Production, Samson Tesfaslasie Aug 1999

Automatic Type Curve Matching For Predicting Gas Wells Production, Samson Tesfaslasie

Graduate Theses, Dissertations, and Problem Reports (ETD)

The determination of gas wells production using type curve matching is one of the methods used in evaluating gas reservoirs. Matching curves manually is time consuming and exposed to human error. Aminian type curves unlike the other type curves accounts the pressure dependency of gas properties and the effect of non-darcy factor. The sensitivity of Aminian type curves to non-darcy factor makes them hard to match with naked eyes.;Sfrac is a computer program generates type curves using conventional calculations for wells where all the reservoir properties are available. Using the idea of Sfrac, a program was developed to generate type …

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Compressive Strength Prediction For Composite Unmanned Aerial Vehicles, Edward Albert Wen Aug 1999

Compressive Strength Prediction For Composite Unmanned Aerial Vehicles, Edward Albert Wen

Graduate Theses, Dissertations, and Problem Reports (ETD)

A rational methodology is presented to predict the compressive strength of carbon/epoxy compression specimens and prototype production parts using the model presented by Barbero in the Journal of Composite Materials, Vol. 32, No.5/1998. The experimental technique is an adaptation of the optical method first proposed by Yurgartis (1987) and can be directly applied to actual development, quality control or failure investigation programs. There is very good agreement between actual and predicted compressive strength at -125F and room temperature. At 180F, the predicted strength is conservative. Aurora Flight Sciences provided the prototype production parts and partial funding under the "Material Characterization …

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Various Pushing Methods On Grid Graphs, Jiaxin Wang Aug 1999

Various Pushing Methods On Grid Graphs, Jiaxin Wang

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis describes algorithms for determining if a grid of switches can be turned into all-off state from any initial configuration by various methods of activation operation (push). Among these push methods, besides the regular "+" push, "+" push with no center, "X" push, "X" push with no center, and a "V"-typed unbalanced push are studied. The research methods used in this work are mainly linear algebra and algorithm analysis. Results obtained include that the grid m x n is completely solvable with push "+" no center, if and only if co-prime (m+1, n+1).

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Surface -Enhanced Raman Spectroscopic Studies Of Organonitriles On Copper Colloids, Candace Mikki Coyle Aug 1999

Surface -Enhanced Raman Spectroscopic Studies Of Organonitriles On Copper Colloids, Candace Mikki Coyle

Graduate Theses, Dissertations, and Problem Reports (ETD)

Dramatic differences are observed between the surface-enhanced Raman spectra (SERS) of organonitriles mixed with copper colloids, the Raman of the free parent molecules, and the SERS for adsorption on a gold colloid. Specifically, nu(C≡N) is missing in the SER spectra involving the copper colloid. The data are adequately explained by a transition metal assisted borohydride reduction of the cyano group to an amino group. SER spectra of the reduction products of the organonitriles in the presence of copper colloids are identical within experimental error. The nu(C≡N) signal was observed when a gold colloid was prepared by borohydride reduction, thereby indicating …

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Characterizing The Chemistry Of Yellow-Poplar Surfaces Exposed To Different Surface Energy Environments Using Dca, Dsc, And Xps, Michael William Carpenter Aug 1999

Characterizing The Chemistry Of Yellow-Poplar Surfaces Exposed To Different Surface Energy Environments Using Dca, Dsc, And Xps, Michael William Carpenter

Graduate Theses, Dissertations, and Problem Reports (ETD)

Surface energy changes in extracted and unextracted yellow-poplar upon exposure to aluminum, teflon, and heat/air surface treatments have been described using dynamic contact angle (DCA) and X-ray photoelectron spectroscopy (XPS) analysis. Results show that the surface molecular orientation of yellow-poplar can be controlled by increasing the temperature above the Tg of lignin with exposure to either an environment of higher (aluminum) or lower (teflon) surface energy. Above the Tg, increases in free volume allows greater molecular mobility that enables increased diffusion of extractives to the surface and reorientation of polymer molecules and/or functional groups. Above the Tg, the wood with …

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Optimization Of A Brushless Permanent Magnet Linear Alternator For Use With A Linear Internal Combustion Engine, William Robert Cawthorne Aug 1999

Optimization Of A Brushless Permanent Magnet Linear Alternator For Use With A Linear Internal Combustion Engine, William Robert Cawthorne

Graduate Theses, Dissertations, and Problem Reports (ETD)

Numerous applications require the generation of electric power without connection to the utility power system. Many industrial, commercial, and personal applications require uninterrupted electrical power in the event of a utility failure. Additionally, the nature of military field operations necessitates the ability to generate electricity in areas where connection to the utility is impractical or impossible. Generation units selected for these applications must be reliable, efficient, compact, and lightweight.;Presently, rotary internal combustion engines coupled with rotary alternators are the primary generation unit used in these applications. This research contends that a tubular brushless permanent magnet linear alternator with a linear …

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Determination Of Optimal Pricing And Warranty Policies, Ozcan Mutlu Aug 1999

Determination Of Optimal Pricing And Warranty Policies, Ozcan Mutlu

Graduate Theses, Dissertations, and Problem Reports (ETD)

An important problem facing manufacturers in today's competitive market is the determination of the selling price of a product and its warranty period. A longer warranty may serve as a signal of product reliability; however, it may also lead to an increase in cost and hence reduce the profit if the product reliability is low. A burn-in test may be used to improve the reliability of products prior to their shipment.;This research presented integrated models for maximizing the expected profit for products that are subjected to a burn-in test and sold with warranty. The burn-in time, warranty period, and price …

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Broadcasting In Grid Graphs, Iwona Wojciechowska Aug 1999

Broadcasting In Grid Graphs, Iwona Wojciechowska

Graduate Theses, Dissertations, and Problem Reports (ETD)

This work consists of two separate parts. The first part deals with the problem of multiple message broadcasting, and the topic of the second part is line broadcasting. Broadcasting is a process in which one vertex in a graph knows one or more messages. The goal is to inform all remaining vertices as fast as possible. In this work we consider a special kind of graphs, grids.;In 1980 A. M. Farley showed that the minimum time required to broadcast a set of M messages in any connected graph with diameter d is d + 2(M - 1). This work presents …

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Trip Generation Rates For Consolidated Schools In West Virginia, Amy Marie Balmer Aug 1999

Trip Generation Rates For Consolidated Schools In West Virginia, Amy Marie Balmer

Graduate Theses, Dissertations, and Problem Reports (ETD)

Currently, there are no trip generation rates for consolidated schools in West Virginia. A consolidated school is a public school that formed from the consolidation of other schools of the same type or a county-wide school. Because West Virginia is rural in nature and declining school-age population, the trip rates for consolidated schools would tend to be different than the national averages for traditional schools.;This research developed trip rates specific to consolidated high, middle, and elementary schools in West Virginia. In total, sixteen different schools in West Virginia were studied. Of the sixteen sites studied, seven were high schools, two …

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Simulation Of Packed Column Jigging, Qiang Dai Aug 1999

Simulation Of Packed Column Jigging, Qiang Dai

Graduate Theses, Dissertations, and Problem Reports (ETD)

Packed column jig has been demonstrated a number of promising results in processing iron ore, coal, chromite and other finely disseminated particulate materials. The packing materials in the jig divide the column into a large number of virtual cells. Each cell performs the similar separation action. A model about the movement of a particle in the packed column jig was derived to interpret the separation mechanism of particles in the virtual cell. A computer program was developed to simulate the particle movement in the jig based on the derived model, which can simulate the packed column jigging with different jig …

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Experiences Of Selected West Virginia Agriculture Teachers Who Have Established Aquaculture Units In Their Schools And Have Taught Aquaculture Classes For Two Years Or More, Paul A. Lovett Aug 1999

Experiences Of Selected West Virginia Agriculture Teachers Who Have Established Aquaculture Units In Their Schools And Have Taught Aquaculture Classes For Two Years Or More, Paul A. Lovett

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study was designed to ascertain and record the experiences of West Virginia agriculture teachers who have established aquaculture units in their schools and have taught aquaculture for two or more years. This study will provide suggestions to those who may yet integrate aquaculture into their curriculum.;A "Focused Interview" was used to gather qualitative data from eight-experienced aquaculture teachers. The respondents answered eight questions that were asked and recorded by the secretary in agricultural and environmental education at WVU to eliminate bias and improve the validity of this study.;The results of this study found that agricultural teachers used aquaculture to …

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Offerings For Jahilia, Stephen Vincent Martonis May 1999

Offerings For Jahilia, Stephen Vincent Martonis

Graduate Theses, Dissertations, and Problem Reports (ETD)

These words represent the ideas invested in my paintings. They are progressive and fluctuating thoughts occurring at an interval in time. They are given honestly and freely, as ignorance and change are understood.

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Design Considerations For Variable Power Split Hydraulic Drives For Industrial Applications, Michael Jan Christian Shellenberger May 1999

Design Considerations For Variable Power Split Hydraulic Drives For Industrial Applications, Michael Jan Christian Shellenberger

Graduate Theses, Dissertations, and Problem Reports (ETD)

Continuously variable transmissions (CVTs) offer some advantages over conventional transmissions in industrial applications. During discrete shifts, conventional transmissions suffer from momentary power transmission lapses, which may produce undesirable effects in the system. Currently, the types of CVTs utilized in industry are hydrostatic drives and hydrodynamic couplings. However, these drives are heavy, presenting an obstacle in applications where weight is a concern. In a power split continuously variable transmission (PS-CVT) the power that flows through the hydraulic element is reduced. This allows the overall size and weight of the transmission to be reduced.;The objective of this thesis is to develop a …

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Incorporating Neural Network Traffic Prediction Into Freeway Incident Detection, Benjamin Todd Taggart May 1999

Incorporating Neural Network Traffic Prediction Into Freeway Incident Detection, Benjamin Todd Taggart

Graduate Theses, Dissertations, and Problem Reports (ETD)

The efficient operation of an incident management system depend Neural network models have been applied to traffic prediction frequently and even repeatedly because of its superior capability in emulating nonlinear systems. However, these traffic prediction models have not been utilized for incident detection. On the other hand, it is expected that the performance of an incident detection algorithm can be improved if an advanced prediction model is incorporated into. Therefore, this study developed several traffic prediction models that were then integrated into incident detection algorithms. The traffic prediction models were developed based on three different choices of independent variables, while …

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Development Of A Decision Support System For Assessment Of Mobile Bridges, Vikram Ramamoorthy May 1999

Development Of A Decision Support System For Assessment Of Mobile Bridges, Vikram Ramamoorthy

Graduate Theses, Dissertations, and Problem Reports (ETD)

The development of a prototype Decision Support System (DSS) for the condition assessment of the Armored Vehicle Launched Bridge (AVLB) has been demonstrated in the current work. AVLB is a mobile bridge that has been used by the US Army for tank and assault vehicle crossing. It is employed for spanning short gaps of 50 feet or less in the terrain. The condition assessment of such bridges, to ensure safety of personnel and tank, is of strategic importance. The methodology of the prototype DSS is based on a refined visual inspection procedure and a previously established vibration measurement technique.;Conforming to …

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Numerical Analysis Of Direct-Chill Casting Of Aluminum Ingot, Yaping Wu May 1999

Numerical Analysis Of Direct-Chill Casting Of Aluminum Ingot, Yaping Wu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Direct chill (DC) semi-continuous casting is the most efficient way to produce large aluminum ingots. This process consists of three main stages; transient stage, steady-state stage, and post-drop stage. During transient stage, the ingot is subjected to rapid cooling rate and thus resulted in the build-up of high thermal stresses that can often lead to ingot cracking failure.;Based on a fully coupled heat-transfer and thermal-stress analysis model, which has been developed using a commercial finite element (FE) package ABAQUS(TM) with a user subroutine developed in-house, the temperature and stress fields were obtained for various casting conditions. Three post-processing programs were …

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Heavy-Duty Emissions Inventory And Prediction, Ravishankar Ramamurthy May 1999

Heavy-Duty Emissions Inventory And Prediction, Ravishankar Ramamurthy

Graduate Theses, Dissertations, and Problem Reports (ETD)

Heavy duty vehicle emissions represent a significant portion of the mobile source emissions inventory. Accurate estimation of their contribution is essential as on-highway and non-road heavy duty diesel emissions account for at least one third of the oxides of nitrogen (NOx) in the inventory. West Virginia University (WVU) has developed an extensive database of continuous transient gaseous emissions levels from a wide variety of heavy duty vehicles in field operation, from which a subset of vehicles (A to J) have been chosen for further analysis. Several different transient cycles were utilized for testing including the Central Business District schedule. The …

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Locating And Mapping Cemeteries In Loudon County, Virginia, Scott Marshall Sizer May 1999

Locating And Mapping Cemeteries In Loudon County, Virginia, Scott Marshall Sizer

Graduate Theses, Dissertations, and Problem Reports (ETD)

Protecting smaller family-type cemeteries is a difficult task in a rapidly growing area. This paper investigates that ways in which Loudoun County, Virginia addressed cemetery protection concerns. Cemetery locational data was captured from a variety of sources and integrated into the countys geographic information system (GIS). The locational information was gathered through digitization and with a Global Positioning System (GPS). Once the cemetery locational information was in the GIS, it was then integrated into an existing land development process.

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Design And Field Testing Of Jointless Bridges, Jason Matthew Franco May 1999

Design And Field Testing Of Jointless Bridges, Jason Matthew Franco

Graduate Theses, Dissertations, and Problem Reports (ETD)

A recent trend in bridge design has been toward elimination of joints and bearings in the bridge superstructure. These joints and bearings are expensive in both initial and maintenance costs, and can get filled with debris, freeze up and fail in their task to allow expansion and contraction of the superstructure. They are also a "weak link" that can allow deicing chemicals to seep down and corrode bearings and support components. Because the design is difficult and their behavior is unknown, they are not widely used despite the enormous benefits. There are no standardized design procedures for these bridges, only …

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Mission Planning And Remote Operated Vehicle Simulation In A Virtual Reality Interface, Christopher Samuel Allport May 1999

Mission Planning And Remote Operated Vehicle Simulation In A Virtual Reality Interface, Christopher Samuel Allport

Graduate Theses, Dissertations, and Problem Reports (ETD)

Virtual reality simulations are finding applications in a wide range of disciplines such as surgical simulation, electronics training, and crime scene investigation. During the Mars Pathfinder Mission, in summer 1997, NASA scientists unveiled a new application of virtual reality for the visualization of a planetary surface. The success of this application led to a more concentrated effort for using virtual reality visualization tools during future missions. The thrust of this effort was to develop a new interface which would allow scientists to interactively plan experiments to be performed by the mission robots. This thesis covers two of the primary aspects …

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Stability Analysis Of Partially Filled Tanker Trucks Using A Finite Element Modeling Approach, Matthew Aquaro May 1999

Stability Analysis Of Partially Filled Tanker Trucks Using A Finite Element Modeling Approach, Matthew Aquaro

Graduate Theses, Dissertations, and Problem Reports (ETD)

The point of rollover for a tanker truck carrying fluid cargo is of great importance due to the catastrophic nature of accidents involving such vehicles. Payloads are often toxic or flammable, thus, predicting the threshold of rollover effectively is of great value. Furthermore, the liquid load shift caused by fluid slosh amplifies the propensity of these vehicles to rollover.;This research presents an approach for determining the threshold of rollover stability of a specific tanker truck by using finite element analysis methods, specifically the software program ANSYS. This approach allows the consideration of many variables which had not been fully considered …

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Inter-Laboratory Variability Of The Marshall Test Method For Asphalt Concrete, Michael S. Hughes May 1999

Inter-Laboratory Variability Of The Marshall Test Method For Asphalt Concrete, Michael S. Hughes

Graduate Theses, Dissertations, and Problem Reports (ETD)

Statistical quality control measures, such as used by the West Virginia Division of Highways (WVDOH), require quantification of the variability of the test methods to set meaningful material acceptance parameters. The Division currently uses the Marshall method for asphalt concrete mix design and quality control. Although the Marshall method will be replaced as the Division transitions to the Superpave method, in the interim, the Division will continue to use the Marshall method. The objective of this project was to determine multi-laboratory precision statements for the Marshall method that the WVDOH can use in developing statistically based quality acceptance specifications.;An experiment …

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Head Impact Characterization Of Generic A-Pillar Of An Automobile, Subramani Balasubramanyam May 1999

Head Impact Characterization Of Generic A-Pillar Of An Automobile, Subramani Balasubramanyam

Graduate Theses, Dissertations, and Problem Reports (ETD)

The need to provide enhanced occupant protection for all impact conditions experienced in automobile crashes poses a great challenge. Several safety features such as seatbelts and airbags have been developed to reduce occupant injuries in the event of a crash. However, new studies have indicated that even with these safety features, head impact with the upper interior components have resulted in many injuries leading to fatalities in certain impact conditions such as side collision and rollover. Recent regulations imposed by NHTSA concerning head impact scenarios in automotive crashes are designed to provide maximum head impact protection against several locations on …

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Robot Navigation Using Ultrasonic Feedback, Akihiko Baba May 1999

Robot Navigation Using Ultrasonic Feedback, Akihiko Baba

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis presents an autonomous navigation program for West Virginia University's mobile robot platform ANT. The program allows the ANT to find a predefined goal by comparing sensor data with a given map of the environment. ANT's ultrasonic sensors were used to sample the surroundings continuously, and this information was combined with dead reckoning data to build a two-dimensional map of the environment. Borenstein's Histogramic In-Motion Mapping technique was used to build sensor maps, which were analyzed to find features such as walls and corners. The features were matched with features in the given map to correct dead reckoning errors. …

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Investigation Of Hot Gas Desulfurization Utilizing A Transport Reactor, David A. Berry May 1999

Investigation Of Hot Gas Desulfurization Utilizing A Transport Reactor, David A. Berry

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis investigated the use of transport reactor technology to conduct hot gas desulfurization (HGD). The need or market drivers for this technology were assessed to identify the demand and opportunity. A literature review was conducted to assess the status of HGD and the issues involved with its development.;Design requirements were identified for integrated gasification combined cycle (IGCC) power plants that would utilize transport HGD reactors to baseline the design for the technology. A target of 1/10 of the New Source Performance (NSPS) for the emission of sulfur dioxide was chosen as the sulfur removal requirement for the system. Process …

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Dynamic Stability Of An Elliptical Pendulum With Unilateral Simple Supports, Heins Naim Karam May 1999

Dynamic Stability Of An Elliptical Pendulum With Unilateral Simple Supports, Heins Naim Karam

Graduate Theses, Dissertations, and Problem Reports (ETD)

The study of rollover stability of partially filled tanker trucks often requires the use of mechanical pendulums to substitute the sloshing dynamics of the fluid. Cylindrical tanks have been effectively characterized by simple pendulums combined with some fixed masses. Just recently, a WVU team proposed the use of an elliptical pendulum to substitute the sloshing dynamics in partially filled elliptical tankers.;In this research, a trammel mechanism is configured as an elliptical pendulum with a unilaterally supported base. That is, the supports on either side can lift off the ground to allow for rollover under certain critical lateral accelerations. Two generalized …

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Simulation Study Of A Kanban-Controlled Production System, Arvind R. Krishnappa May 1999

Simulation Study Of A Kanban-Controlled Production System, Arvind R. Krishnappa

Graduate Theses, Dissertations, and Problem Reports (ETD)

Just-In-Time (JIT) has become one of the most popular production control philosophies in the last three decades. JIT did not find acceptance in the American companies until after the oil crisis. To be more flexible and to adapt quickly to changes in the market, many American companies took to the recourse of JIT and have been extremely successful. JIT systems typically employ kanbans as a means of inventory control. A JIT system operating under kanban control is commonly termed as a "pull system" due to the way in which succeeding stages trigger production at preceding stages. Owing to this close …

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