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Two-Echelon Logistics Model For Recoverable Items With Lateral Supply In The Army., Kwanghui. Chai
Two-Echelon Logistics Model For Recoverable Items With Lateral Supply In The Army., Kwanghui. Chai
Electronic Theses and Dissertations
This paper develops a Two-echelon logistics model for recoverable items with lateral supply in a single period in the Army. It derives formulas for distribution and inventory costs, and determines the optimal stock level at a depot and at a base to minimize the backorders. During the period, a Poisson demand and distinct units of operating bases which stocks can be shared are assumed. It allows the lateral supply between operating bases. A two-phase method is used to get solutions to the stock level constrained optimization problem. The outcome of this paper can be applied to lower level of logistics …
Vibration Balancing Analysis Of A Dual Face Mill Eccentric Grinder Machine Head., Jason Kyle. Kushniruk
Vibration Balancing Analysis Of A Dual Face Mill Eccentric Grinder Machine Head., Jason Kyle. Kushniruk
Electronic Theses and Dissertations
Balancing of machinery is a well known technical aspect of engineering which is practiced throughout the world. Many studies have been performed to optimize the models and methods used to make rotor balancing faster and more efficient. This thesis deals with the unique problems associated with the balancing of eccentrically designed spindles for the machine tool industry. Cobra Machine Tool Limited has designed and patented the newest form of combination face mill and grinder operation in North America. The study performed in this analysis provides a benchmark for further vibration studies by the company in the future. Standard vibration measurement …
Scheduling In A Dual Resource Constrained System Using Genetic Algorithms., Vishvas. Patel
Scheduling In A Dual Resource Constrained System Using Genetic Algorithms., Vishvas. Patel
Electronic Theses and Dissertations
In this research a solution methodology and a software program system for assignment of dual resources (Machines and Workers) were developed. By considering two dual resource constrained problems as the candidate problems, an optimized GA based heuristic was developed. First genetic algorithms were used to determine the optimal staffing level which can be viewed as a basic design decision. Second, genetic algorithms were used to make short range control decisions regarding the operations of dual resource constrained shop. Six different dispatching rules such as SPT, EOPNDD, EDD, FCFS, LSO, LPT and eight performance criteria were used. The performance of each …
Single-Angle Compression Members Welded By One Leg To Gusset Plates., Sherief Sharl Shukry. Sakla
Single-Angle Compression Members Welded By One Leg To Gusset Plates., Sherief Sharl Shukry. Sakla
Electronic Theses and Dissertations
Single-angle compression members are simple structural elements that are very difficult to analyse and design. These members are usually attached to other members by one leg only. Thus the load is applied eccentrically. To further complicate the problem, the principal axes of the angle do not coincide with the axes of the same or truss of which the angle is a part. Although it is known that the end conditions affect the ultimate load carrying capacity of these members, procedures have not been developed to do this as it is difficult to evaluate the end restraint in many practical cases. …
Smart Drilling: A Computer-Based System For Planning Drilling Operations., Jia. Ma
Smart Drilling: A Computer-Based System For Planning Drilling Operations., Jia. Ma
Electronic Theses and Dissertations
In this thesis, a prototype computer aided process planning system--Smart Drilling System is presented. The system will be able to automatically generate plans for multiple hole drilling process, such as tool selection, drilling sequence, and etc. The system contains four modules: (1) Tool selection module, (2) Machining condition design module, (3) NC code generation module, and (4) Simulation module. In the tool selection module, a generative searching and planning algorithm is applied. Fuzzy logic was utilized to make decisions in tool selection. The module can group the drills according to their size and shape, and select optimal drills that will …
Thickness Measurement Of Curved Multilayered Polymer Structures Using The Ultrasonic Pulse-Echo Method., Hong. Shao
Thickness Measurement Of Curved Multilayered Polymer Structures Using The Ultrasonic Pulse-Echo Method., Hong. Shao
Electronic Theses and Dissertations
Ultrasonic inspection is accomplished by using electronically controlled pulses introduced into a material from an outer surface. Then, the ultrasonic energy travels within the material, finally reaching again an outer boundary. Material condition is diagnosed from characteristics of the receive ultrasonic energy. The technique of using ultrasonic pulse echo to investigate and examinate the thickness of curved multilayered structures will be presented in this thesis. It also studied physics conditions which the curvatures of multilayered polymer systems might effect thickness measurements. The real location of the focus of an acoustic beam in curved layered structures was calculated by a ray-optical …
Experimental Investigation Of Incipient Boiling And Incipient Quenching Of R-123., Li. Liang
Experimental Investigation Of Incipient Boiling And Incipient Quenching Of R-123., Li. Liang
Electronic Theses and Dissertations
Experiments were carried out to investigate the factors which affect the incipient boiling wall superheat for a copper/refrigerant R-123 interface and to compare these results with the behaviour predicted by the Martin-Dominguez nucleation site boiling model. The factors which affect the boiling behaviour of individual nucleation sites as well as the actual surface incipient boiling characteristics such as fluid and system conditions were studied using a facility which produced vertical flow in an annulus between an electrically heated 22.2 mm (0.875 in) outside diameter cooper tube and a 25.4 mm (1 in) internal diameter glass tube. The experimental observations allowed …
A Study Of The Life Cycle Assessment Of Multilayer Plastic Fuel Tank., Dan. Albu
A Study Of The Life Cycle Assessment Of Multilayer Plastic Fuel Tank., Dan. Albu
Electronic Theses and Dissertations
One of the objectives of the Life Cycle Assessment (LCA) is to evaluate environmental burdens associated with a product, process or activity by quantifying energy and materials used and wastes released to the environment. The assessment includes the entire life cycle of the product encompassing raw material processing, manufacturing, transportation, use, recycling and disposal. This paper analyzes the multilayer plastic fuel tank from the LCA perspective, determines the main environmental burdens and expands the analysis on the improvement areas of the product for the purpose of lowering the environmental burdens. Many companies in the private sector are beginning to see …
Comparison Of Tactile Probe Cmm And Laser Scanning Techniques For Reverse Engineering., Yan. Liu
Comparison Of Tactile Probe Cmm And Laser Scanning Techniques For Reverse Engineering., Yan. Liu
Electronic Theses and Dissertations
In this thesis, the strategies of reverse engineering using tactile probe CMM and laser scanning techniques are described and applied in practice. Examples are given by reverse engineering geometric primitives including a plane, a sphere and a two-radius cylinder as well as free-form surfaces including a car tail light and a manifold surface. Through these examples, the effect of the probing angle of the laser scanner as well as the CMM on the accuracy of the measurement data is revealed. The problems with surface modeling are studied and the solutions to build a surface model from different geometry curves with …
Influence Of Psmc And Other Mineral Admixtures On The Properties Of Cement Mortar., George Jianzhou. Xu
Influence Of Psmc And Other Mineral Admixtures On The Properties Of Cement Mortar., George Jianzhou. Xu
Electronic Theses and Dissertations
PSMC is a waste material produced from pyrolysis of Sheet Molding Compound. The material consists of 35% fibreglass, 55% CaCO$\sb3$ and 10% carbon. In this thesis, PSMC and seven other related materials have been investigated for their influences on the overall properties of cement mortar. The materials under investigation in addition to PSMC are the fibreglass part of PSMC (PG), the filler part of PSMC (C+Ca), the ground virgin fibreglass (RG), the virgin CaCO$\sb3$ powder, the pyrolysed automotive fluff (PAF). For comparison, one class-F fly ash (FA), and one condensed silica fume (CSF) were also tested. The mortar properties that …
Buckling Of Built-Up Columns., Ghada Mohamed. Elmahdy
Buckling Of Built-Up Columns., Ghada Mohamed. Elmahdy
Electronic Theses and Dissertations
The problem of built-up columns has been under investigation since the collapse of the Quebec Bridge in 1907, which occurred due to the failure of the lower chords. It was reported that these elements were not designed as latticed columns. It is widely accepted that built-up columns exhibit reduced shear stiffness resulting in an increase in lateral deflection. This reduction in shear stiffness leads to a reduction in the strength of the column, which may be accounted for by increasing the slenderness ratio of the built-up member to an equivalent slenderness ratio. One of the questions addressed by this research …
The Effect Of Elbow Position And Grip Span On Isometric Grip Strength And Force Distribution Of Fingers., Xuewei (Sue). Chen
The Effect Of Elbow Position And Grip Span On Isometric Grip Strength And Force Distribution Of Fingers., Xuewei (Sue). Chen
Electronic Theses and Dissertations
Injuries to the hand, lower arm, and shoulder are often attributed to inappropriate use or poor design of hand tools. Isometric grip, performed with the angled handles of pliers was investigated in this study. For this thesis, three factors were studied. They were grip type (traditional and reversed grip), elbow position (0$\sp\circ$, 30$\sp\circ$, 60$\sp\circ$, 90$\sp\circ$, and 120$\sp\circ$), and grip span (50, 60, and 70 mm). The resultant forces between the jaws of the pliers and finger forces were measured under each condition. The purpose of this study was to evaluate the effect of elbow position and grip span on grip …
Hydraulic Study Of Secondary Stilling Basins., Taban. Sowlati Hashjani
Hydraulic Study Of Secondary Stilling Basins., Taban. Sowlati Hashjani
Electronic Theses and Dissertations
In dams with low tailwater levels, the hydraulic jump may not occur on the protected apron. This could result in a severe local scour on the downstream river bed which could endanger the safety of the dam. A traditional solution is to place crushed rock in the scour hole to prevent further scour; however, this method is not a permanent solution. The focus of this research is to investigate the effect, on the scour profile, of installing a secondary stilling basin downstream of the primary basin. This results in a dual stilling basin. The primary stilling basin is the original …
Improving The Performance Of Soil-Metal Structures Subjected To Loss Of Soil Support., Karlos Ernesto. Melgar
Improving The Performance Of Soil-Metal Structures Subjected To Loss Of Soil Support., Karlos Ernesto. Melgar
Electronic Theses and Dissertations
Years of dependable service and a multitude of wide ranging installations have led to the corrugated steel pipe industry to play a major role in modern engineering technology. Flexible steel conduits play an important role in the form of culverts, storm sewers, subdrains, spillways, underpasses, conveyor conduits and service tunnels; for highways, railways, airports, municipalities, recreation areas, industrial parks, flood and conservation projects, water pollution abatement and many other programs. In recent years developments have been made which allow engineers and contractors the use of conventional corrugated structural plates to design and build structures having larger spans and increased permissible …
A Skew Third Order Upwinding Scheme For Modelling Settling Tanks., Hany Zarif Amin. Gerges
A Skew Third Order Upwinding Scheme For Modelling Settling Tanks., Hany Zarif Amin. Gerges
Electronic Theses and Dissertations
A new high accuracy numerical technique has been developed. This technique is based on a Skew Third Order Upwinding Scheme (STOUS) which eliminates numerical diffusion. This scheme introduces cross-difference terms to overcome the instability problems of the component-wise one-dimensional formulas for simulating multi-dimensional flows. Small physically unrealistic overshooting and undershooting have been avoided by using a well established technique known as the Universal Limiter. STOUS is also compared with another third order upwinding technique which is referred to as Uniformly Third Order Interpolation Algorithm (UTOPIA). A complete von Neumann stability analysis is conducted on both schemes to show the stability …
Compressive Strength Of Steel Single Angles Loaded Through Two-Bolts In One Leg., Raymond. Haidar
Compressive Strength Of Steel Single Angles Loaded Through Two-Bolts In One Leg., Raymond. Haidar
Electronic Theses and Dissertations
One hundred and ninety seven steel single angles loaded through two bolts in one leg were tested for their compressive strengths. They included five different sizes (76 x 51 x 6.4, 127 x 76 x 6.4, 64 x 64 x 6.4, 64 x 64 x 4.8, and 76 x 76 x 6.4 mm) and slenderness ratios varying from 69 to 201. The gauge distances were varied from the minimum to the maximum possible value for each size of angle. The effect of the connection type (snug tight and pretensioned) was also investigated. The effect of the width of the connected …
Effect Of Be On The Nucleation And Growth Of Beta' Phase In Aluminum-Magnesium-Silicon Alloy., Ali. Hatab
Effect Of Be On The Nucleation And Growth Of Beta' Phase In Aluminum-Magnesium-Silicon Alloy., Ali. Hatab
Electronic Theses and Dissertations
An investigation on the effect of Be on $\beta\sp\prime$ phase precipitation in Al-0.7%Mg-0.4%Si alloy was carried out using microhardness and resistivity measurements, and optical and TEM observations. It is shown that addition of 0.4%Be to an Al-0.7%Mg-0.4%Si (base) alloy significantly enhances the age hardening response and increases the peak hardness levels of the alloy, which is associated with a refinement of the $\rm\beta\sp\prime(Mg\sb2Si)$ precipitate. Hardness and resistivity techniques used to study the precipitation kinetics show that the two methods are in good agreement for monitoring the transformation rates. A kinetic analysis shows that A precipitation of $\beta\sp\prime$ phase in both …
Parameterizing And Capturing Diagnostics Information During Design., Roozbeh. Rahimpour
Parameterizing And Capturing Diagnostics Information During Design., Roozbeh. Rahimpour
Electronic Theses and Dissertations
This thesis presents a new methodology for constructing a device's computer model to be used as the knowledge-base component of the model-based diagnostics expert system of the device. It is shown that parameterized functional and behavioural knowledge of a device could be applied to the diagnostics action to pin point the root cause of a fault. Four underlying concepts which are examined and deployed in this thesis to support the proposed methodology are: Parametric and feature based design, object oriented methodology for analysis and design, manufacturing as incorporating useful information into material, and using functional knowledge in diagnosing faults. The …
A Model Of Operation Allocation With Lot Splitting In Flexible Assembly Systems., Fazlullah. Sharief
A Model Of Operation Allocation With Lot Splitting In Flexible Assembly Systems., Fazlullah. Sharief
Electronic Theses and Dissertations
In this thesis, the loading problem in Flexible Assembly Systems (FASs) has been studied. Two integer programming models of the loading problem are presented. The first model is an extension of an earlier 0/1 integer programming model which takes into consideration the unit transportation costs. The total cost in model 1 thus is a summation of assembly costs and unit transportation costs. An operation in a FAS may be performed at more than one station. However, this capacity is not fully explored and taken advantage of if the complete production requirements of an assembly are sent to one station only …
An Object-Oriented Fuzzy Expert System For The Design Of Rotating Operations., Xin. Yuan
An Object-Oriented Fuzzy Expert System For The Design Of Rotating Operations., Xin. Yuan
Electronic Theses and Dissertations
In the thesis, a prototype object-oriented fuzzy expert system called SAM (Smart Assistant to Machinist) is presented for rotating cutter selection and cutting condition design. Object-Oriented Design and Programming Methods are employed to construct and implement the system. Based on partial and imprecise information, the system is able to select rotating cutter products available in current commercial market, and design cutting conditions for an optimized objective. The system consists of four modules: a database, a rule base, a cutter selection module and a cutting condition design module. The database consists of six kinds of data files: machinability of workpieces, machining …
Optimal Automotive Door-Body Fitting For Body-In-White Assembly., Essam. Shalash
Optimal Automotive Door-Body Fitting For Body-In-White Assembly., Essam. Shalash
Electronic Theses and Dissertations
Flexible manufacturing is a multi-faceted term that has been used in the automotive industry to imply a multitude of manufacturing criteria. A prominent area of application for such criteria in the automotive industry is the body assembly process. The assembly process is, in turn, divided into a number of sub-processes which include fitting car doors to body openings. As these operations take place before the painting of the car body, they are commonly known as Body in White processes. The door fitting problem is ranked within the top issues of car-quality, since an inadequate door fit causes water leakage, wind …
Viscometric Behavior Of Dilute Dewaxed Base Oil-Polymer Solutions Over A Wide Temperature Range., M. Jason. Warren
Viscometric Behavior Of Dilute Dewaxed Base Oil-Polymer Solutions Over A Wide Temperature Range., M. Jason. Warren
Electronic Theses and Dissertations
Four polymers were dissolved in a dewaxed base oil to concentrations of 0.1, 0.2, 0.3, 0.5, and 0.7% by mass to determine their potential as viscosity index improvers (VIIs). The polymers employed in this study included a hydrogenated diene copolymer, a dispersant olefin copolymer, an olefin copolymer, and polymethacrylate. Kinematic viscosities and densities of the base oil and dilute-polymer solutions were measured at $-25,-20,-10$, 0, 10, 20, 40, 60, 80, 100, 120, and 150$\sp\circ$C. Since it was not possible to measure the densities at $-30,-15,-5$, and 5$\sp\circ$C, only the kinematic viscosities were recorded. Relative and specific viscosities of dilute-polymer solutions …
Laboratory Scale Modelling Of Soil Vapour Extraction (Benzene, Toluene, Ethylbenzene, Xylene)., Grant Charles. Hilbers
Laboratory Scale Modelling Of Soil Vapour Extraction (Benzene, Toluene, Ethylbenzene, Xylene)., Grant Charles. Hilbers
Electronic Theses and Dissertations
An innovative in-situ remedial technology, soil vapour extraction (SVE), was simulated in the laboratory. Two types of soil, a sandy soil and an organic top soil, were packed into 1 m tall and 100 mm diameter stainless steel columns. Benzene, toluene, ethylbenzene and xylene, known collectively as BTEX, were added to the soils individually and as a mixture. Before addition to the soils, all contaminants were added to water, to achieve a concentration of 150 mg/L. The conditions simulated in this set-up were similar to those found in a gasoline contaminated soil that has undergone sufficient vapour stripping to remove …
Prediction Models For The Integration Of New Technology Into The Automotive Manufacturing Infrastructure., Leo Paul. Oriet
Prediction Models For The Integration Of New Technology Into The Automotive Manufacturing Infrastructure., Leo Paul. Oriet
Electronic Theses and Dissertations
With the introduction of increasingly expanded world markets in the 1990's, manufacturers are now obliged to compete with the best the world has to offer. Human infrastructures working with robust, capable and in-control processes depend on comprehensive appraisal of the Ergonomic implications for new technologies introduced in manufacturing operating systems. These core values and beliefs are now becoming part of a tightly linked decision-making process which is now being increasingly utilized by most successful manufacturers of world class products. World class manufacturers will welcome and integrate new technologies with the human infrastructure and do whatever it takes for worker protection. …
Effects Of Acoustic Pressure Pulses On Wall Wetting In An Intake Port., Robert B. Haramic
Effects Of Acoustic Pressure Pulses On Wall Wetting In An Intake Port., Robert B. Haramic
Electronic Theses and Dissertations
This study was undertaken to determine whether pressure pulses that propagate through the induction system of a port injected engine influence wall wetting occurring on the surfaces of the intake port. Water was used as the working fluid to eliminate the need for a special room and measures otherwise required to deal with fire hazards that would be present if gasoline were used. An extensive experimental apparatus was constructed that would permit the control of air flow, fuel pressure, throttle position and acoustic pressure pulse amplitude while allowing measurements to be made of wall wetting that occurs in the intake …
A 0-1 Integer Programming Model For The Simultaneous Allocation Of Operations Of Part Types And Grouping Of Machine-Tool Combinations., Franklin Samuel Jaiselvan. Foulger
A 0-1 Integer Programming Model For The Simultaneous Allocation Of Operations Of Part Types And Grouping Of Machine-Tool Combinations., Franklin Samuel Jaiselvan. Foulger
Electronic Theses and Dissertations
In today's competitive world, for manufacturers to survive in the market and to compete on a global level, several innovative strategies are being developed and practised. In industries which manufacture a variety of products in lots, one of the well known manufacturing strategies or systems is cellular manufacturing systems (CMS). CMS has several advantages especially for manufacturers who produce a medium variety of products in medium volumes. The tangible benefits are reduction in cycle time of the product, reduced inventory, improved quality, possibility to meet customer demands on time etc.; the intangible benefits are flexibility in the system, increased control …
Modelling Intelligent Control Of Material Handling Equipment In A Distribution Centre., Soumitra. Basu
Modelling Intelligent Control Of Material Handling Equipment In A Distribution Centre., Soumitra. Basu
Electronic Theses and Dissertations
In an increasingly automated environment, the control of material handling tasks in a goods distribution center is an activity which requires the fusion of various disciplines of engineering in order to identify the appropriate automation tools which could prove beneficial. Various factors influence the effectiveness of automated equipment in a goods distribution centre. It is necessary to control not only scheduling and routing of goods, but also material handling equipment, which are becoming increasingly autonomous. This dissertation addresses the problem of devising a control system so that (a) material flow and (b) material handling equipment are both controlled. A discrete …
Modelling The Allocation Of Pallets In A Flexible Manufacturing Cell., Balakrishnan. Baskar
Modelling The Allocation Of Pallets In A Flexible Manufacturing Cell., Balakrishnan. Baskar
Electronic Theses and Dissertations
Pallets are an essential part of manufacturing operations. This research concentrates on pallets for machining and, in particular, pallets for use in a flexible manufacturing cells (FMC). Flexible manufacturing has received widespread attention in the modern manufacturing environment. A close look at the research done on different areas of flexible manufacturing shows that the aspect of pallets in the design stage has been neglected. The objective of this research, therefore, is to develop mathematical programming models which deals with the palletizing problem in flexible manufacturing. The models assume that there is a set of existing machines in a manufacturing shop …
Surface Finish Enhancement In A Turning Operation Via Control Of The Depth Of Cut., Evangelos. Liasi
Surface Finish Enhancement In A Turning Operation Via Control Of The Depth Of Cut., Evangelos. Liasi
Electronic Theses and Dissertations
During the past two decades there has been a steady increase in the number of computer numerically controlled (CNC) machine tools. Such problems as dimensional accuracy and surface finish are recently receiving widespread attention. This theoretical investigation explores the possibility of decreasing the surface roughness by suppressing radial tool-workpiece relative displacements via control of the depth of cut. In order to achieve this goal various control strategies are developed and evaluated via simulation. An integrated model of the turning process in the most flexible component which manifests itself in the surface roughness, i.e., the radial direction was generated from an …
Enhancement Of Btex Biodegradation In Subsurface Environments., Nataliya. Kordonska
Enhancement Of Btex Biodegradation In Subsurface Environments., Nataliya. Kordonska
Electronic Theses and Dissertations
Massive consumption of petroleum and petroleum products in the world frequently leads to soil contamination by fuel components. The compounds of main concern are: benzene, toluene, ethylbenzene, and xylene, which are highly toxic. The bioremediation technology depends on the alteration of physical and chemical conditions in the subsurface environment to optimize microbial activity. In this study, several techniques of soil remediation enhancement were investigated. BTEX-degraders were selected from the wastewater treatment sludge biota and used as inoculum later. The acclimation was performed on the granular activated carbon (GAC) columns supplied with aromatic hydrocarbons as the only source of carbon and …