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Full-Text Articles in Engineering

Management Of Construction Jobsite Productivity : A Self Assessment Approach, Nicos Poliviou Nicolaou May 1989

Management Of Construction Jobsite Productivity : A Self Assessment Approach, Nicos Poliviou Nicolaou

Theses

A critical component of construction project management is the improvement of jobsite productivity. This paper proposes a procedure for use by project managers to assess jobsite productivity performance. The methodology provides a framework which when applied will identify specific aspects of the jobsite where potential productivity improvement is possible. A major feature is its systematic approach which will direct the project manager to the specific resources which when better managed will lead to lower construction costs.


In Vitro Biocompatibility Study To Determine The Synergistic Effect Of Components For An Artificial Bone Graft Material, Levelle Elise Burr Alexander May 1989

In Vitro Biocompatibility Study To Determine The Synergistic Effect Of Components For An Artificial Bone Graft Material, Levelle Elise Burr Alexander

Theses

A composite bone graft material which can induce or promote new bone growth has potential orthopaedic applications in the repair of bone defects or the stabilization of surgically implanted devices. This material should be biocompatible, have good handling properties, promote osteoinduction and/or osteoconduction and have a good shelf life. Demineralized bone matrix and bone morphogenetic protein have been demonstrated to promote osteoinduction in vitro and in vivo.

This in vitro study examined the inductive ability of an osteoinductive protein, bone morphogenetic protein, when absorbed on non-active devitalized bone matrix. In culture, fetal rat muscle was grown on powdered rabbit demineralized …


An Intelligent Electrocardiogram Tutoring Package Ekgchallenger, Santosh K. Ananthraman May 1989

An Intelligent Electrocardiogram Tutoring Package Ekgchallenger, Santosh K. Ananthraman

Theses

This thesis presents the development and implementation of an intelligent electrocardiogram tutoring package, namely, EKGCHALLENGER which is meant for use in medical schools to teach medical students a method of diagnosing electro cardiograms.

EKGCHALLENGER is an IBM - PC based, user friendly package. It works in two basic modes. The first is a tutorial mode wherein the user is taught the step-by-step diagnosis of electrocardiograms ( EKGs ) which are presented in order of increasing difficulty. The second is the challenger mode wherein the user is asked to diagnose EKGs which are randomly chosen from an EKG database. The diagnosis …


Performance Enhancement & Fault Detection Of Cmos Dynamic Logic For Vlsi, Ashok Arunachalum May 1989

Performance Enhancement & Fault Detection Of Cmos Dynamic Logic For Vlsi, Ashok Arunachalum

Theses

New CMOS dynamic latches are designed which can be used along with conventional dynamic circuits to realize fast pipelined dynamic logic. Also a new method is described for detecting the difficult CMOS Non-classical faults viz. stuck open and stuck on faults. The conventional Domino logic is redesigned to make all the stuck open and stuck on faults detectable.


Investigation Of Surface Formation In Abrasive Waterjet Cutting, Shy-Shyan Chen May 1989

Investigation Of Surface Formation In Abrasive Waterjet Cutting, Shy-Shyan Chen

Theses

This study is concerned with experimental and numerical investigation of the dynamics of surface generation during the impingement of the abrasive waterjet on a workpiece.

A series of erosion zones were generated by the abrasive waterjet on the polished surface of stainless steel samples. The impingement was carried out at different traverse speeds and abrasive flow rates. An optical, a scanning electron microscope and a laser displacement sensor were used to investigate the developed surface.

The microscopical examination of the surface enabled determination of the shape of asperities created by individual particles, distribution of asperities on the surface and the …


Transverse Electric (Te) And Transverse Magnetic (Tm) Mode Conversion In Optically Active (Chiral) Embedded Polymeric Waveguides, Mingdeh Chien May 1989

Transverse Electric (Te) And Transverse Magnetic (Tm) Mode Conversion In Optically Active (Chiral) Embedded Polymeric Waveguides, Mingdeh Chien

Theses

Wave propagation in an optically active isotropic, polymeric thin film waveguides is studied. The waveguides are fabricated using the dipping method. Thin film layers are composed of a passive PMMA (poly methyl methacrylate) host material and a chiral, optically active, ((s)-(+)-1,1'-Binaphthyl-2,2'-dily hydro phosphate), guest material. Experimental results show about 1° per centimeter rotation of polarization as light propagates through a 1.8cm waveguide. The theoretical analysis of the mode structure and wave propagation in the waveguide are examined using first order coupled mode theory. TE (-4 TM mode converter is a typical application of this investigation.


Anaerobic Biodegradation Of Trichloroethylene By Activated Carbon Fluidized-Bed, Yeam-How Chin May 1989

Anaerobic Biodegradation Of Trichloroethylene By Activated Carbon Fluidized-Bed, Yeam-How Chin

Theses

Abstract - The biodegradation of Trichloroethylene by using anaerobic activated carbon fluidized bed has been investigated in the present study. High quality effluent was obtainable when the TCE influent concentration was up to 2.4 ppm in the first stage. Glucose was introduced as a cosubstrate to determine the effects of glucose/TCE ratio on the COD, Glucose and TCE removal. The experimental data indicates that the overall TCE removal efficiency was only slightly affected by TCE loading, but the first stage performance was significantly influenced by TCE loadings. It was also found that the microbial activities were affected by TCE loadings …


The Applicability Of Parametric Inverse Scattering For Optical Waveguides With Imperfect Boundaries, Hyoung Jin Choi May 1989

The Applicability Of Parametric Inverse Scattering For Optical Waveguides With Imperfect Boundaries, Hyoung Jin Choi

Theses

In this thesis, the applicability of an inverse scattering technique for an optical waveguide with imperfect boundaries is investigated. The inversion of imperfect boundaries of waveguides is different from usual inverse scattering algorithms because only eigenmodes can propagate in a waveguide. We suggest a parametric inversion method based on the first-order coupled mode equation. The validity and usefulness of the method are demonstrated using examples of periodic and almost periodic imperfect boundaries.


Implementation Of The Sliding Dictionary Data Compression Algorithm On An At&T Dsp 32 Digital Signal Processor, Shu Fang May 1989

Implementation Of The Sliding Dictionary Data Compression Algorithm On An At&T Dsp 32 Digital Signal Processor, Shu Fang

Theses

Compared with other data compression algorithms, the sliding dictionary is more practical for implementation in hardware. After a comprehensive study of the algorithm, an on line data compression scheme which uses AT&T DSP 32 Digital Signal Processor has been developed. Assembly language programs for encoder and decoder have been written and tested. The whole compression system has been simulated in a real-time environment and results have been obtained. A quantized coding scheme has been used to increase compression ratio. Separate assembly language programs have been written to implement the quantized coding scheme and tested. Results obtained from real-time simulation are …


Adaptive Subband Video Coding With Motion Compensation, Manjunatha S. Kadur May 1989

Adaptive Subband Video Coding With Motion Compensation, Manjunatha S. Kadur

Theses

An efficient scheme for video sequence coding is presented here. The interframe redundancy present in the video sequence is exploited by motion compensation using the efficient independent orthogonal search technique, which requires least number of computations in the worst case. The motion compensated frame difference signal is encoded with a new technique — subband adaptive vector quantization.

Subband coding like transform coding results in signals of unequal energy patterns, which is efficiently utilized for bit allocation. In addition, the subband approach offers means for efficient (but suboptimal) Vector Quantization (VQ) by splitting the signal into several signals. By rate distortion …


Variations Of Alkalinity, Ph, Oxidation Reduction Potential, And Conductivity In Single And Multi-Stage Sludge Digestion Systems, Nasser M. Kamazani May 1989

Variations Of Alkalinity, Ph, Oxidation Reduction Potential, And Conductivity In Single And Multi-Stage Sludge Digestion Systems, Nasser M. Kamazani

Theses

Anaerobic digestion is used at many municipal and industrial wastewater treatment plants. Recent increase in the cost of energy and search for an alternative source of energy for the future have prompted renewed interest in anaerobic digestion for energy recovery by production of methane from waste materials, including wastewater sludges and agricultural and municipal solid wastes. Accordingly, a large literature exist on the subject, most of it dealing with more physical aspects of different process design. Little or not enough attention has been paid to its highly complex biochemical characteristics.

The purpose of this study is a preliminary investigation regarding …


Simulation And Off-Line Programming Of Robotic Workcells, Krishnaprasad V. Kamisetty May 1989

Simulation And Off-Line Programming Of Robotic Workcells, Krishnaprasad V. Kamisetty

Theses

A typical, complex robotic workcell, namely NJIT's Flexible Manufacturing System (FMS) cell has been designed, modelled and simulated to bridge the gap between design and its implementation. McDonnell Douglas' (McAuto) PLACE, BUILD, COMMAND and ADJUST have been used to simulate entire cycle of the NJIT's FMS cell. Various aspects such as "Cycle Time Analysis", robot reachability of various positions in the cell and "Collision Detection" have also been studied and analyzed.

The ease of effecting any modifications to the existing workcell design has been demonstrated. The NJIT's FMS cell consists of the GE P-50 robot, the IBM 7535 robot, the …


Csma/Cd Lan Performance : Modeling And Simulation In Csim, Nanda K. Kanuri May 1989

Csma/Cd Lan Performance : Modeling And Simulation In Csim, Nanda K. Kanuri

Theses

A simulation model to analyze the performance of CSMA/CD protocol is developed. CSIM, a process oriented simulation language, is used. Performance measures such as throughput, average delay and maximum delay per packet are presented. System performance is analyzed for different loads, number of stations, and network lengths, with packet length as parameter. By trading off the throughput and delay time, an optium packet length can be selected from simulated performance curves. A general scheme for MAC protocols modeling is provided.


Output Feedback Applied To Observer Based Controller, Nainn-Ping Ke May 1989

Output Feedback Applied To Observer Based Controller, Nainn-Ping Ke

Theses

This thesis presented the results of an investigation on the stability robustness issues of the Infinite-horizon linear-quadratic-Gaussian (IH-LQG) control system design methodology. The goal of this research deals with the design of Observer based controller using Output Feedback (00F), and this is a new method to solve estimation problems. The primary difference of this method from others is that the estimator is considered as a system. The results of this research shows that the optimal output feedback control law and the optimal state estimator can be designed by the optimal output feedback control method, and shows that the OOF Weighting …


Feasibiltiy, Planning, And Justification Of Fms : A Case Study, Joo Hwan Kim May 1989

Feasibiltiy, Planning, And Justification Of Fms : A Case Study, Joo Hwan Kim

Theses

FMS production technology, because of its ability to adjust to changes in product demands and produce at competitive costs even on small runs and at above quality levels, has caused its adoption by the major automobile manufacturers. These attributes are of particular interest to Korean automobile manufacturers who due to a small home market need to manufacture in relative small quantities and to export.

This paper considers how such a technology can be implemented. It discusses the key factors to be considered such as strategy, selection and design of the appropriate hardware and software, required organizational changes, and its economic …


Investigation Of The Distribution Of Particles In An Abrasive Water Jet, Sun Kim May 1989

Investigation Of The Distribution Of Particles In An Abrasive Water Jet, Sun Kim

Theses

This study is concerned with the distribution of abrasive particles within an abrasive waterJet. The Jet is generated by the Ingersoll Rand nozzle set at the different diameters of the sapphire nozzles and carbide mixers. Water pressure is maintained at 4.7- 4.9 ksi.

The distribution of particles is examined by the separation of the central and adjacent part of the flow and the measurement of the fractions of the mixture and abrasive in the separated region. The separation is carried out by diamond washers coaxial with a carbide mixer. The second series of experiments involve the estimation of the Jet …


Visual System Modeling And System Response Analysis, Zhongquan Li May 1989

Visual System Modeling And System Response Analysis, Zhongquan Li

Theses

Based on the anatomical structure, a structural model of the visual system was established. System responses of different stimulations were analyzed based on the model. More extensive study was made on the system impulse response. A mathematical model with parameters representing prominent process components was developed to represent the system response in a compact form and the parameters were statistically studied to correlate to the real physiological characteristics of the visual system. The parameters of the model were used to fit the system intensity response function. The result shows that it is a more quantitative way to construct the system …


The Effects Of Degraded Indoor Air Quality On Employees Working In High Rise Office Buildings, Richard Patrick Luongo May 1989

The Effects Of Degraded Indoor Air Quality On Employees Working In High Rise Office Buildings, Richard Patrick Luongo

Theses

An examination of the effects of poor indoor air quality on workers in high rise office buildings was conducted. These effects are manifested physiologically, psychologically and economically and originate from sources inside and outside the building, as well as from the building's ventilation system. These sources include combustion products, microorganisms, volatile organic chemicals, cigarette smoke and miscellaneous chemicals. Lower productivity and higher absenteeism are the initial results of these effects. If the situation becomes chronic, an erosion of trust between employer and employee can occur which may eventually serve as the basis for litigation, such as worker's compensation claims and …


Red Blood Cell Deformability Testing By Using A Rheological Method, Zhenglei Ma May 1989

Red Blood Cell Deformability Testing By Using A Rheological Method, Zhenglei Ma

Theses

A rheological model of blood has been used for testing red cell deformability. The result of the testing is characterized by five parameters of the model. We suggested that the rheological behavior of blood is affected by red cell deformability. The result of the parameter C of the model, which is the kinetic rate constant of the structural breakdown of rouleaux into individual erythrocytes induced by shearing, from decreased red cell deformability group higher than that from normal control group lead to a criterion for separating normal subjects from decreased red cell deformability. The easy experiment method of using whole …


Distributed Data Collection System Based On Hierarchical Network, Harish Mahindrakar May 1989

Distributed Data Collection System Based On Hierarchical Network, Harish Mahindrakar

Theses

On line data collection systems are essential in order to satisfy the requirements for real-time applications. Typical applications are computer integrated manufacturing, security control, hourly wage calculations, human resources management. On line data collection system makes it possible to closely monitor and track different operations with more accuracy. On line data collection systems eliminate redundant work, save time and money.

If the distributed system is based on a multicontroller, it becomes really cost effective solution to build such a system.

This effort is the design of a distributed multicontroller system, required in a data collection system. A hierarchical network is …


Study Of System Dynamics In A Primitive Identification/Counter Model, Zofia Monczka May 1989

Study Of System Dynamics In A Primitive Identification/Counter Model, Zofia Monczka

Theses

Previous study of a simplified identification/counter model (1), (2) indicated bifurcations in its behavior. In order to study this topic, graphical representations of the system dynamics are derived. Analysis of the structure of the identification/counter model reveals the reasons why the graphs assume their given shapes.

The graphical representations of the system are used to characterize the system behavior and thus explain the bifurcations previously encountered. These representations are then used as the basis for deriving a general model for system behavior. Analysis of this model for a specific range of parameter values indicates that the system contains numerous additional …


Sediment Transport/Sand Bypassing Analysis At Manasquan, Nj, Christopher Clemens Obropta May 1989

Sediment Transport/Sand Bypassing Analysis At Manasquan, Nj, Christopher Clemens Obropta

Theses

An experiment to determine the longshore sediment transport rate using a fluorescent dyed sand tracer was conducted during the summer of 1987 to help determine the feasibility of sand bypassing at the Manasquan Inlet in New Jersey. After the fluorescent sand tracer was introduced to the longshore transport system, the Spatial Integration Method was used to sample the surf zone. The Spatial Integration Method allowed the tracer cloud to be monitored in both time and space. The tracer experiment provided a constant to be used in the calculation of the longshore sediment transport rate. This constant is specific to the …


Laboratory Model Studies Of Pneumatic Fracturing Of Soils To Remove Volatile Organic Compounds, Panayiotis Papanicolaou May 1989

Laboratory Model Studies Of Pneumatic Fracturing Of Soils To Remove Volatile Organic Compounds, Panayiotis Papanicolaou

Theses

Bench-scale laboratory studies were conducted from January 1988 to October 1988 to demonstrate the feasibility of using Pneumatic Fracturing* to enhance the removal of Volatile Organic Compounds from the vadose soil zone. Experiments were conducted to investigate: 1) The effect of pneumatic fracturing on the rate of contaminant removal; and 2) the injection pressures required to initiate soil fracturing.

Contaminated soil was placed and compacted in three identical 15 inch square by 30 inch high plexiglass tanks. The first tank was equipped with a vapor extraction system consisting of vacuum and/or positive air injection. The second tank was equipped with …


A Dynamic Cmos Programmable Logic Device, Praveen K. Parvathala May 1989

A Dynamic Cmos Programmable Logic Device, Praveen K. Parvathala

Theses

This thesis presents the design of a Dynamic CMOS Programmable Logic Device chip (NJIT PLD). The main feature of the chip is its reconfigurability and the provision of a processor interface which makes the chip capable of performing coprocessor like functions. The chip has been designed to be used with the Intel 8088 microprocessor, but may also find stand-alone applications. Provision is made for dynamic reconfiguration of the chip. The configuration data for the chip comes from a serial PROM, to which the chip sends a synchronizing clock. The NJIT PLD is a high performance, digital integrated circuit. It has …


Survival Rate Study Of Intrashock Versus Postshock Microwave Rewarming In Rats Subjected To Hemorrhagic Shock, Hani M. Patel May 1989

Survival Rate Study Of Intrashock Versus Postshock Microwave Rewarming In Rats Subjected To Hemorrhagic Shock, Hani M. Patel

Theses

In search for a more effective treatment for rewarming of profound accidental hypothermia, a comparative survival rate study was conducted of intrashock versus postshock microwave rewarming in rats subjected to hemorrhagic shock. In an anechoic chamber, rats were illuminated with 50 Watts of continuous microwave power supplied by a 915 MHz microwave generator. This frequency corresponds to a free-space wavelength of about 33 cm. The incident-power density was calculated to be about 8.5 mW/cm2, and the whole-body specific absorption rate (SAR) was calculated to be 14.5 W/kg.

The microwave postshock group showed a significantly higher post shock survival rate than …


Trellis Encoded M-Ary Partial-Response Schemes, Raju P. Patel May 1989

Trellis Encoded M-Ary Partial-Response Schemes, Raju P. Patel

Theses

Convolutional codes can be used to improve the reliability of partial-response channels in a Gaussian noise environment. Multilevel partial-response schemes can be used to increase the information rate in a given bandwidth compared to binary partial-response schemes. This thesis deals with the theory and construction of convolutionally encoded 4-ary partial- response schemes. The free Euclidean distance of the combined trellis of rate-1/2 convolutional code and 4-ary partial-response scheme is found through a computer search, using the Viterbi-algorithm.

The matched encoding concept is also applied to find the conditions for matched encoding for combined trellis of rate-1/2 convolutional codes and 4-ary …


Hardware And Software Designs For Integrated Electrical Engineering Experiments, Sujin Pramojaney May 1989

Hardware And Software Designs For Integrated Electrical Engineering Experiments, Sujin Pramojaney

Theses

The interfacing between the various electrical engineering fields is not emphasized in the electrical engineering laboratory; the traditional aim of a laboratory course is to complement a single theoretical course. The object of this thesis is to provide means, hardware and software, that can be used in different system configurations to perform useful industrial tasks. The chosen task is to control electrical machines using a microcomputer. Experiments can be written to be performed by students, using these systems. The emphasize of these experiments can be on the characteristics of a power electronics device, but the device will be seen as …


Network Realizability Approach To Robust Stability Of Discrete-Time Systems Characterized By Polynomials, Sri Indran Rasiah May 1989

Network Realizability Approach To Robust Stability Of Discrete-Time Systems Characterized By Polynomials, Sri Indran Rasiah

Theses

In system design, the coefficients of a characterizing polynomial are usually not precisely known but can be bounded from above and below by real numbers. The requirement of robust system design from the stability standpoint demands, then, the guaranteeing of the stability of a set of polynomials.

Stability theorems for continuous-time systems and discrete-time systems, are studied in this report. It is shown that one more condition has to be included into each of the theorem. The revised theorem for continuous-time systems is proved through network realizability theory. The one for discrete-time systems is, then, proved via the use of …


Design Of Governor-Turbine Models In Stability Studies, Vidyanand Swaminathan May 1989

Design Of Governor-Turbine Models In Stability Studies, Vidyanand Swaminathan

Theses

This thesis investigates the effect of hydro governor-turbine models on the steady state stability of an automatically controlled electric power system. Basically two kinds of hydro governor-turbine models, namely, Impulse and Francis type are studied in depth. Design of a compensating network has also been proposed, which can help improve the stability conditions of a power system which employs a poor governor-turbine model.

The power system investigated includes a large sized hydro generating unit connected to an infinite bus via a power network. This generator employs a modern three-channel fast-acting automatic voltage regulator (AVR). For any operating condition, stability results …


Slurry Wall Backfill Integrity And Desiccation, Mahendraratnam Thilliyar May 1989

Slurry Wall Backfill Integrity And Desiccation, Mahendraratnam Thilliyar

Theses

The upper reaches of slurry wall, in a waste containment structure may under go cycles of wetting and drying, because of seasonal ground water level fluctuations. This may result in desiccation and cracking of back fill material. Experiments were conducted to study these effects with water, aniline, phenol, hydrochloric acid solutions on soils containing different proportions of bentonite, kaolinite, and sand. The largest crack was formed with phenol and the smallest with water. With hydrochloric acid no crack was formed. With increase kaolinite content, the width and density of crack decreased. Hydraulic conductivity tests on cracked specimens indicated high hydraulic …