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Full-Text Articles in Engineering

Robotic Arms With Flexible Links As The Links Approach Rigidity, George A. Downes Sep 1989

Robotic Arms With Flexible Links As The Links Approach Rigidity, George A. Downes

Theses

The dynamics of single link flexible robotic arms are modeled using the Bernoulli-Euler beam equation and Lagrange's equation. The Bernoulli-Euler beam equation derivation is reviewed and is studied in the limiting case as the flexiblity approaches zero. Using the Bernoulli-Euler beam equation, a procedure is developed to calculate the position of the endpoint of a link given the displacement, slope or curvature of any point on the link. Also a procedure is developed to calculate the minimum Young's modulus of elasticity, E, given a specified endpoint displacement tolerance.

A rigid link model based on Lagrange's equation and a flexible link …


Theoretical Analysis Of Universal Joint With Manufacturing And Assembly Tolerances, Xiaosong Liu Sep 1989

Theoretical Analysis Of Universal Joint With Manufacturing And Assembly Tolerances, Xiaosong Liu

Theses

The model for a Cardan joint with manufacturing and assembly tolerances is a spatial four-bar mechanism with one rotating and three cylindrical joints. In this thesis, dual-number coordinate transformation matrices and Newtonian mechanics are applied to provide a concise description of the kinetics of the universal joint. The dual-Euler equations are used to derive the dynamic equations of the Cardan joint. The analytical technique presented here yields explicit expressions. It will provide the designer with better insight into the workings of the kinematics and dynamics of the Cardan joint.

The equations of statics and dynamics of the frictionless universal joint …


Equation Of Interaction Diagrams For Prestressed Concrete Columns, Angamuthu Palaniappan Sep 1989

Equation Of Interaction Diagrams For Prestressed Concrete Columns, Angamuthu Palaniappan

Theses

A general analysis and design equation for prestressed concrete column is proposed. This equation represents the strength interaction diagrams of prestressed concrete columns under bending about one axis and combined with axial load. The equation proposed is a modification of the one developed by Dr. Hsu, C.T. Thomas for reinforced concrete columns published in the ACI structural journal in 1988. The analytical results were compared with the results of tests on 30 eccentrically loaded prestressed columns reported by H.R. Brown and A.S. Hall. The results were in good agreement with the static analysis and the above mentioned test reports. The …


Design And Analysis Of An Intracranial Pressure And Temperature Sensor Telemetry System, Anshumat Parasar Sep 1989

Design And Analysis Of An Intracranial Pressure And Temperature Sensor Telemetry System, Anshumat Parasar

Theses

This thesis presents a signal conditioning and telemetry system for an implantable pressure and temperature transducer. The initial target application is for measuring the epidural intracranial pressure in the range of 25-100 millitorr and temperature over the range 90 — 110° F. The implant, based on custom silicon IC design can be packaged within a volume of 2cm3 and will require surgical procedures for placement and removal. Effort has been made in this thesis to design the transducer, associated signal conditioning and telemetry circuits for useful operation over a wide range of power supply voltage. The implanted device is powered …


On-Line Dot Matrix Code Verification, Thatta V. Premnath Sep 1989

On-Line Dot Matrix Code Verification, Thatta V. Premnath

Theses

Machine vision principles are increasingly applied in the areas of manufacturing and automated inspection. The objective of this thesis work is to investigate different methods that could be implemented for matching printed dot matrix characters with the actual characters to be printed.

In support to this investigation, a survey of various methods proposed by researchers in the field of Optical Character Recognition (OCR) is presented. Survey includes a detailed description of the state-of-the art methods. It is shown that due to restrictions of hardware cost and the time available to inspect each character, the standard approaches are not practical. Hence, …


Experimental Study Of Rectangular And Square Concrete Member Under Combined Biaxial Bending And Tension, Ming-Hua Shiau Sep 1989

Experimental Study Of Rectangular And Square Concrete Member Under Combined Biaxial Bending And Tension, Ming-Hua Shiau

Theses

The proposed research is based on an equation developed by Dr. Hsu, which represents the strength interaction diagrams and failure surface for reinforced concrete rectangular and square columns under combined biaxial bending and axial load. In this research, two rectangular columns and two square columns subject to biaxial bending and tension were tested and compared with the proposed failure surface equation. This study shows that the experimental test results achieve more strengths then those calculated by the equation of failure surface.


Agitation Requirements For Complete Drawdown Of Floating Solids In Stirred Tanks, Joseph Philemon Mmbaga Sep 1989

Agitation Requirements For Complete Drawdown Of Floating Solids In Stirred Tanks, Joseph Philemon Mmbaga

Theses

The agitation requirements for complete drawdown of floating solids in mechanically agitated tank vessels has been studied both theoretically and experimentally.

A semi-theoretical equation has been derived on the basis of Kolmogoroff's theory of isotropic turbulence to determine the minimum impeller speed required for drawdown. The equation contains one adjustable parameter which has been found to be a function of the impeller type and position in the tank vessel.

The equation was tested using various vessels and impeller configurations. The solid phase consisted of high density polyethylene (density = 897kg/m3), low density polyethylene (density = 840kg/m3) …


Process Modelling Of The Nitration Of Toluene, Nitin K. Shah Sep 1989

Process Modelling Of The Nitration Of Toluene, Nitin K. Shah

Theses

The thesis on the process modelling of the nitration process focuses specifically on the product separation of the nitrated aromatic material from the reactor and - wash section of the process. Included in the text is an overview of the main process steps associated with the production of para and ortho-nitrotoluene. The critical issues concerning the reaction of nitric acid and toluene were summerized, and resulted in this subject being deferred for future work.

The separation of the isomers into pure components is an important. part of the MNT process because of the close high boiling points of the isomeric …


Thermal Decomposition Of Chlorobenzene Reaction With Hydrogen And Oxygen Mixture In An Atmosphere, Chun-Chen Yang Sep 1989

Thermal Decomposition Of Chlorobenzene Reaction With Hydrogen And Oxygen Mixture In An Atmosphere, Chun-Chen Yang

Theses

The thermal reactions of chlorobenzene in hydrogen and oxygen mixtures were studied in tubular flow reactors at 1 atmosphere total pressure. Experiments were carried out in flow reactors of varied diameter for determining effects of different surface to volume ratios. Residence times ranged from 0.03 to 2.5 seconds and temperature was varied over a range of 560 - 660 °C. The 02/H2 ratios ranged from 1% to 5%.

It was found that the conversion of chlorobenzene in hydrogen and oxygen mixtures increased with both temperature and residence time. The oxidation of chlorobenzene also occurred more rapidly when oxygen concentraction was …


Recursive System Identification Using Least Squares Method, Gholamreza Ghorbani Moghadam Sep 1989

Recursive System Identification Using Least Squares Method, Gholamreza Ghorbani Moghadam

Theses

Input and output sampling, in addition to computer simulations, are now an integral part of system identification. In this thesis, the concept of analyzing any time invariant continuous deterministic system will be developed by identifying a linear discrete - time system equivalent to the continuous one. In this method, two computer programs are written in pascal. The first program applies the Recursive Least Squares Method to discrete - time systems in order to estimate the system components. The second program estimates the future output of the system. Four systems have then identified using the programs.

In this process, system identification …


Evaluation Of Sorting Algorithm Performance On Single Instruction Multiple Data Machines, Dong Kuen Yang Sep 1989

Evaluation Of Sorting Algorithm Performance On Single Instruction Multiple Data Machines, Dong Kuen Yang

Theses

Partitioning an application program into several tasks and executing them via parallel processing is one way to increase computation throughput and performance. But with a uniprocessor system, the performance increase will be minimal. Computer scientists have developed several multiprocessor systems to gain more speed in computation.

There are several computer architectures, such as pipeline machines, array processors and multiprocessor systems. They provide a parallel execution environment to increase the execution speed. But as the system becomes more complex, the communication traffic density between several processors increases more heavily. It has to provide some kind of control algorithm or routing function …


Adaptive Transform Coding Of Video With Motion Compensation And Vector Quantization, Jung-Hui Chien Sep 1989

Adaptive Transform Coding Of Video With Motion Compensation And Vector Quantization, Jung-Hui Chien

Theses

This thesis proposes an efficient transform coding scheme for the low bit rate video sequence. The redundancy within adjacent video frame is exploited by motion compensated interframe prediction using the efficient independent orthogonal search technique, and the motion compensated frame difference (MCFD) signal is transform coding by 1-D DCT, 1-D HDCT and 2-D DCT, the coefficients are zonal masked, and vector quantizatied adaptively. The encoded MCFD as well as the motion information and variance grouping (side informations) are transmitted to the receiver to reconstruct the frame. The transform MCFD signal is classified into the four groups according to the coefficient …


Protein Separation With Mathematical Modeling For Chromatographic Operation, Hsien-Chih Ma Aug 1989

Protein Separation With Mathematical Modeling For Chromatographic Operation, Hsien-Chih Ma

Dissertations

We have performed experiments and derived mathematical models for packed bed columns used for liquid phase chromatographic separations of proteins with impulse input of feed solutions. These models can now be used to describe the relationships between the elution characteristics (peak height, peak position, and shapes) and the operating conditions (flow rate and buffer conditions) of ion exchange and gel permeation column chromatography for protein separations.

The surface adsorption model was discussed relative to the nature of the mobile and stationary phases in ion exchange column chromatography for two distinct cases: with and without pore diffusion. For large solute molecules, …


Protocol Processing Delay Analysis On Ethernet By Simulation Of Njit Ethernet, Jagdish Gangrimal Rangwani Aug 1989

Protocol Processing Delay Analysis On Ethernet By Simulation Of Njit Ethernet, Jagdish Gangrimal Rangwani

Theses

CSMA/CD based Local Area Networks account for about 75% of the installed LAN base today. As these networks are becoming available for high channel bandwidth, it is important to identify the bottlenecks in these networks. As channels are becoming high speed, bottleneck is shifting from channel to protocol processing. This delay depends on a particular implementation of the protocol and not the protocol standard itself.

This Thesis presents the analysis of delay on Ethernet. To achieve realistic results NJIT Ethernet, as it is configured, is modelled and simulated. Traffic on this network is measured and load on each segment is …


Effects Of N>M Clos Networks On Edge Coloring And Matrix Decomposition Algorithms, Ming-Hsing Lin Aug 1989

Effects Of N>M Clos Networks On Edge Coloring And Matrix Decomposition Algorithms, Ming-Hsing Lin

Theses

Considered in this thesis are n > m Clos networks on edge coloring and matrix decomposition algorithms. This work uses a two-fold approach to examine the effects of n > m Clos networks on edge coloring and matrix decomposition algorithms. First, edge coloring and matching on bipartite multigraphs are applied to routing on Clos networks. It is demonstrated that edge coloring algorithms which find a minimum edge coloring set up the routing for n > m Clos networks with redundancy. The results presented here indicate that the Euler coloring algorithm has applications on n > m Clos networks because it has fast time complexity …


A Comparison Of The Fracture Toughness, Hardness, Impact Strength, And Thermal Expansion Of Two Dental Porcelains, Nancy Maignon Aug 1989

A Comparison Of The Fracture Toughness, Hardness, Impact Strength, And Thermal Expansion Of Two Dental Porcelains, Nancy Maignon

Theses

Dental Porcelains are known to be very brittle materials. Ongoing research is being undertaken to obtain a porcelain of optimum strength. A recent development in this field is the new porcelain Optec HSP.

In this comparative study, a series of mechanical test were performed on both Optec HSP and Ceramco II.

An indentation technique was used to calculate the hardness and fracture toughness, the Izod method with a 1 ft-lb pendulum was used to obtain the impact strength, and the thermal expansion was calculated with the Dupont thermal analyser.

For each material, a sample size of five and twenty specimens …


Semiconductor Pressure Sensor And Amplifier With Extended Temperature Range, Abhay Mahadeo Joshi Aug 1989

Semiconductor Pressure Sensor And Amplifier With Extended Temperature Range, Abhay Mahadeo Joshi

Theses

In this thesis work, a unique raicrosensor was designed for pressure measurements over the temperature range of -80 C to 125 C. The sensor has CMOS circuitry powered by a single voltage supply. It can be used for military and space applications including monitoring the pressure acting on the nose of the space shuttle.

The sensor consists of a thin silicon diaphragm, which is stressed by external pressure. Four resistors in a Wheatstone bridge configuration are diffused into the diaphragm. The temperature drift in the silicon sensors is dominated by the temperature dependence of the piezoresistive coefficients. The resistors are …


Optimization Of Throughput And Stability For Csma/Cd Channel, Liangshyng Jou Aug 1989

Optimization Of Throughput And Stability For Csma/Cd Channel, Liangshyng Jou

Theses

Multiple access technologies plays an important role in designing distributed computer communication system. Here, CSMA/CD has attracted researchers' attentions in the last ten years. In this paper, based on attributions of the slotted, nonpersistent CSMA/CD system, performance of CSMA/CD channel is analyzed. Adaptive Retransmission Technique is adopted to obtain the maximum throughput. Also, equilibrium contours are derived to discuss the stability of the system. And use FET to measure the stability of CSMA/CD channel that FET gives an approximate measure of the average uptime of an unstable channel.


A Cad For Edif Pattern Generation, Mohammad Akram Khan Aug 1989

A Cad For Edif Pattern Generation, Mohammad Akram Khan

Theses

Generating a set of test vector for a digital circuit is the most critical step in design and test. It is very important to generate test sequence easily and efficiently. The importance is enhanced by the fact that the simulation database is being used to create test programs. A CAD tool ATPG (Automatic Test Pattern Generator) has been developed to specify and satisfy requirements of designers and test engineers. EDIF (Electronic Design Interchange Format) is followed closely. EDIF targets compatability among foundry services and CAD/CAE systems.


Quantification Of Refining Actions, Hari R. Goyal Aug 1989

Quantification Of Refining Actions, Hari R. Goyal

Masters Theses

The repeated action of compression-decompression pulses on a wet web of fiber, created by dropping a weight from a height, loosens the internal structure of the fiber. The impaction of fiber did not cause any change in average weighted fiber length, fine content or Canadian Standard Freeness. The sheet made from these fibers showed an increase in tensile strength with increased number of impacts or impact intensity.

In a blend of impacted fibers (internally fibrillated), abraded fibers (externally fibrillated) and fines (fibers shorter than 0.23 mm and created by prolonged beating in a Valley beater), fines were found to be …


An Ergonomic Training Program For Manual Handling Tasks, Akhilesh Agrawal Aug 1989

An Ergonomic Training Program For Manual Handling Tasks, Akhilesh Agrawal

Masters Theses

The objective of this study was to test whether or not muscular endurance of individuals engaged in industrial manual handling tasks can be improved through a short and intensive training program. This investigation also involved the study of the effect of muscular endurance training program on muscular strength.

The study revealed that, over a six-week period, the muscular endurance can be improved significantly. After sixteen sessions of training, the endurance time increased over 500% for manual materials handling tasks and over 1200% for upper extremity manual handling tasks. The endurance training program, however, did not increase both static and dynamic …


A Comparative Study Of The Performance Of Various Image Analysis Methods For Dimensional Inspection With Vision Systems, Ralf Heinrich Koeppe Jul 1989

A Comparative Study Of The Performance Of Various Image Analysis Methods For Dimensional Inspection With Vision Systems, Ralf Heinrich Koeppe

Dissertations and Theses

Dimensional inspection with Vision Systems requires a careful selection of image analysis methods in order to obtain accurate information about the geometry of the parts to be measured.

The purpose of this project is to study, implement and compare different image evaluation methods and to show their strengths and weaknesses with respect to dimensional inspection. Emphasis is made on the inspection of circular features. The criteria of comparison for these methods are discussed. Using synthetically generated images, various analysis methods are compared and conclusions for their use are drawn. Results of the comparison show that the selection of a method …


Numerical Study Of Three-Dimensional Separation And Flow Control At A Wing/Body Junction, Balakrishnan Lakshmanan Jul 1989

Numerical Study Of Three-Dimensional Separation And Flow Control At A Wing/Body Junction, Balakrishnan Lakshmanan

Mechanical & Aerospace Engineering Theses & Dissertations

The problem of three-dimensional separation and flow control at a wing/body junction has been investigated numerically using a three-dimensional Navier-Stokes code. The numerical code employs an algebraic grid generation technique for generating the grid for unmodified junction and an elliptic grid generation technique for filleted fin junction. The results for laminar flow past a blunt fin/flat plate junction demonstrate that after grid refinement, the computations agree with experiment and reveal a strong dependency of the number of vortices at the junction on Mach number and Reynolds number. The numerical results for pressure distribution, particle paths and limiting streamlines for turbulent …


Evaluation Of Equilibrium Turbulence For A Hypersonic Boundary Layer At Nonadiabatic Wall Conditions, Cindy W. Albertson Jul 1989

Evaluation Of Equilibrium Turbulence For A Hypersonic Boundary Layer At Nonadiabatic Wall Conditions, Cindy W. Albertson

Mechanical & Aerospace Engineering Theses & Dissertations

This paper presents an experimental study to characterize the compressible turbulent boundary layer produced along a flat plate in the NASA Langley 8-Foot High Temperature Tunnel and determine the test conditions necessary to achieve equilibrium turbulence. In addition, the present study extends the data base for equilibrium compressible turbulent boundary layers over quasi-isothermal walls which are far from the adiabatic wall temperature. The measurements consist of pilot pressure, static pressure, and total temperature distributions in the boundary layer. A flat plate measuring 9.7 feet long and 4.3, feet wide was used for the study to provide a naturally turbulent boundary …


Determinations Of Molecular Weight And Molecular Weight Distribution Of High Polymers By The Rheological Properties, Joan Y. Z. Huang Jul 1989

Determinations Of Molecular Weight And Molecular Weight Distribution Of High Polymers By The Rheological Properties, Joan Y. Z. Huang

Mechanical & Aerospace Engineering Theses & Dissertations

Several methods are reviewed by which the molecular weight (MW) and molecular weight distribution (MWD) of polymeric material were determined from the rheological properties. A poly (arylene ether) polymer with six different molecular weights was used in this investigation. Experimentally measured MW and MWD were conducted by GPC/LALLS (Gel Permeation Chromatography/Low Angle Laser Light Scattering), and the rheological properties of the melts were measured by a Rheometric System Four rheometer. It was found that qualitative information of the MW and MWD of these polymers could be derived from the viscoelastic properties, with the methods proposed by Zeichner and Pate1, and …


Investigating The Method Of Structural Topological Variations For Sensitivity Analysis And Design Optimization, Niki A. Mehta Jul 1989

Investigating The Method Of Structural Topological Variations For Sensitivity Analysis And Design Optimization, Niki A. Mehta

Mechanical & Aerospace Engineering Theses & Dissertations

The method of structural topological variations is a newly developed technique for analysis of frame structures. It provides a novel method that completely avoids formulating and solving simultaneous equations, required in the finite element displacement method. The principal objective of this thesis is to investigate the method of topological variations as a possible design tool and study its applicability in the sensitivity analysis and in the process of design optimization.

A computer code was developed for this method to obtain its comparative performance against the finite element displacement method. For analysis of large structures involving frequent local modifications, the method …


Global/Local Stress Analysis Of Composite Structures, Jonathan B. Ransom Jul 1989

Global/Local Stress Analysis Of Composite Structures, Jonathan B. Ransom

Mechanical & Aerospace Engineering Theses & Dissertations

A method for performing a global/local stress analysis is described and its capabilities are demonstrated. The method employs spline interpolation functions which satisfy the linear plate bending equation to determine displacements and rotations from a global model which are used as "boundary conditions" for the local model. Then, the local model is analyzed independent of the global model of the structure. This approach can be used to determine local, detailed stress states for specific structural regions using independent, refined local models which exploit information from less-refined global models. The method presented is not restricted to having a priori knowledge of …


Explicit And Implicit Calculations Of Turbulent Cavity Flows With And Without Yaw Angle, Guan-Wei Yen Jul 1989

Explicit And Implicit Calculations Of Turbulent Cavity Flows With And Without Yaw Angle, Guan-Wei Yen

Mechanical & Aerospace Engineering Theses & Dissertations

Computations have been performed to simulate turbulent supersonic flows past three-dimensional deep cavities with and without yaw. Simulation of these self-sustained oscillatory flows have been generated through time accurate solutions of the Reynolds averaged complete Navier-Stokes equations using two different schemes: (1) MacCormack, finite-difference, (2) implicit, upwind, finite-volume schemes. The second scheme, which is approximately 30% faster, is found to produce better time accurate results. The Reynolds stresses have been modeled, using the Baldwin-Lomax algebraic turbulence model with certain modifications. The computational results include instantaneous and time averaged flow properties everywhere in the computational domain. Time series analyses have been …


Stability Design Of A Slender Column With Curved Longitudinal Stiffeners, Mark S. Lake Jul 1989

Stability Design Of A Slender Column With Curved Longitudinal Stiffeners, Mark S. Lake

Mechanical & Aerospace Engineering Theses & Dissertations

This thesis presents the results of a stability design study of a slender column with curved longitudinal stiffeners for large space structure applications. The stiffened column concept is attractive because it allows the buckling load of a slender column to be increased at a fairly low cost in increased mass, and at no change in the column packaged size. Linear stability analyses are performed using a "linked-plate" representation of the stiffeners to determine stiffener local buckling stresses. Results from a set of parametric analyses are used to determine an approximate explicit expression for stiffener local buckling in terms of its …


Optimal Algorithmic Testing Of Re-Programmable Logic Arrays, Arvind Chopra Jun 1989

Optimal Algorithmic Testing Of Re-Programmable Logic Arrays, Arvind Chopra

Theses

This research delineates a test strategy and detailed sequence of test vectors for a new class of programmable logic devices (PLDs). This new class of devices is based on architectures that contain programmable logic arrays (PLAs) programmed by on chip integrated static RAMs or EEPROMS. The new PLD architecture poses unique testing problems which require 100% nodal test coverage. Previous PLAs/PLDs did not require that 100% of the nodes be tested since their circuits utilized fuse link crosspoints and were not dynamically reprogrammable. Such devices could be tested by a unique personality pattern that combined the application and the test …