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Wastewater Treatment : Phenol Extraction By Liquid Membrane, Jan-Ming Hou May 1988

Wastewater Treatment : Phenol Extraction By Liquid Membrane, Jan-Ming Hou

Theses

Two models for the extraction of phenol by means of liquid surfactant membranes is presented in which external mass transfer around w/o emulsion drop, phase and chemical equilibria are taken into account.

The nonlinear coupled P.D.E.'s is solved under assumptions to get a close-formed analytical approximate solution. The experimental results on the batch extraction of phenol are found to be satisfactory simulated by one of the proposed models provided that phenol concentration is higher than 0.01N. The model requires no adjustable parameter thus it can predict the extraction behavior without doing experiments.


Recycled Plastics As Fillers In Polymer Cement Concrete Composites, Shian-Jong Liu May 1988

Recycled Plastics As Fillers In Polymer Cement Concrete Composites, Shian-Jong Liu

Theses

How to handle the plastic waste is a big task for the modern society in environmental protection. People already focus on it, especially in PET soft drink bottles. Although PET bottle can be reclaimed, its usages are restricted due to the limitation in color and difficulty in purification.

On the other side, concrete is the most common material for human beings to used [sic] in construction. Concrete has good compressive strength, but poor [sic] in flexural and tensile strengths, which limits its applications. So, scientists try to improve its properties by adding the polymer into the conventional concrete, to enhance …


System Performance Criteria In Cdma Networks Using Gold Codes, Yong H. Kim May 1988

System Performance Criteria In Cdma Networks Using Gold Codes, Yong H. Kim

Theses

First, we have presented the autocorrelation and crosscorrelation properties for periodic and aperiodic binary sequences. The generation of binary sequences using shift registers with feedback was reviewed. We have also included correlation properties for the Gold codes.

Next, we discussed Gold code generation for the balanced and unbalanced Gold codes.

Thirdly, we investigated the number of simultaneous users in a CDMA system using Gold codes for the worst case and the average case of mutual interference.

Finally, we simulated the probability of interference exceeding a threshold value, and the average crosscorrelation value caused by interference in a CDMA network which …


Modeling And Simulation Of Robot Arms With Flexible Links, John G. Danis May 1988

Modeling And Simulation Of Robot Arms With Flexible Links, John G. Danis

Theses

The design of lightweight robot arms introduces a degree of flexiblity in the individual links which renders the arm difficult to control. Solution of the control problem requires accurate and detailed mathematical models of the arm dynamics. A comprehensive survey of the current literature in this area has shown that although many such models exist, there is a great diversity in their structure, function, and applicability. The different objectives and techniques of model development which lead to this diversity are examined and summarized in this thesis. Bases for classification of the mathematical models and techniques of development are established, and …


Agitation Requirements For Complete Dispersion Of Emulsions, Dun-Huang Tsai May 1988

Agitation Requirements For Complete Dispersion Of Emulsions, Dun-Huang Tsai

Theses

An investigation on the minimum agitation speed required to achieve complete dispersion in liquid-liquid systems has been carried out. A model based on the momentum balance for a droplet and on Kolmogoroff's theory of isotropic turbulence was used for the prediction of the role of the most important variables on the minimum agitation speed. The equation so derived can be expressed in terms of a number of non- dimensional groups (such as Re, Ar, and Su). For geometrically similar systems the equation contains only one adjustable parameter ( to be determined experimentally) in the form of the proportionality constant correlating …


Use Of Recirculation Reactor To Study Biodegradation Of 2-Chlorophenol, Kai-Chung Yang May 1988

Use Of Recirculation Reactor To Study Biodegradation Of 2-Chlorophenol, Kai-Chung Yang

Theses

The performance of immobilized cells in the treatment of hazardous waste was investigated using a recirculation flow reactor run in a batch mode. A mixed microbial population from a municipal wastewater treatment plant was immobilized in calcium alginate gel. The bio-oxidation ability of these microbes towards a model toxin (2-chlorophenol) was studied. The process parameters studied were as follows:

  1. Flow rate of the recycle stream;
  2. Biomass loading;
  3. Spiking concentration of 2-chlorophenol;
  4. Use of buffered vs. non-buffered defined medium.

Dissolved oxygen concentration was monitored using a flow Clark-type dissolved oxygen probe. Oxygen consumption was correlated with the biodegradation of 2-chlorophenol. Physical …


Preconcentration And Direct Flame Ionization Method For Measurement Of Non-Methane Organic Compounds In Ambient Air And Statistical Analysis Of Experimental Data, Lianyi Zuo May 1988

Preconcentration And Direct Flame Ionization Method For Measurement Of Non-Methane Organic Compounds In Ambient Air And Statistical Analysis Of Experimental Data, Lianyi Zuo

Theses

A fast and reliable method for the determination of non-methane organic compounds (NMOC) in ambient air has been developed. Samples are collected in SUMMA polished stainless steel canisters using a sampling system with a critical orifice as flowrate controller. Analysis of NMOC in the atmosphere via a canister is carried out by cryogenic preconcentration and a direct flame ionization detection method (PDFID). This system is sensitive and provides accurate measurement of ambient NMOC concentration even if the concentration is as low as 0.1 ppm carbon. The performance of the method was characterized using 19 pairs of canister samples and tested …


Detection And Determination Of N-Nitrosohexamethyleneimine In Benzenesulfonamide, N-[[(Hexahydro-1-H Azepin-1-Yl)Amino]-Carbonyl]-4 Methyl By Hptlc, Anulfo A. Valdez May 1988

Detection And Determination Of N-Nitrosohexamethyleneimine In Benzenesulfonamide, N-[[(Hexahydro-1-H Azepin-1-Yl)Amino]-Carbonyl]-4 Methyl By Hptlc, Anulfo A. Valdez

Theses

A simple method, by High Performance Thin Layer Chromatography HPTLC), was developed for rapid determination of N-Nitrosohexamethyleneimine in Benzenesulfonamide, N-[((hexahydro-1 H Azepin-1-yl)amino]-Carbonyl]-4 methyl, (Tolazamide). Separation of N-Nitrosohe-xamethyleneimine from a Tolazamide solution in chloroform was obtained by precipitation of Tolazamide with n-heptane and by passing the resulting clear solution through a small silica column which was eluted with methanol.

Determination of the N-nitroso compound was achieved by ultraviolet irradiation of it on activated High Performance Silica Gel Plates. Detection was performed by spraying the plates with triethylamine and fluorescamine reagent giving a fluorescent product. Visual detection limits of 25 ppb were …


Synthesis Of Strained Bridgehead Lactams, Quansing Tu May 1988

Synthesis Of Strained Bridgehead Lactams, Quansing Tu

Theses

While 1-Azabicyclo(3,3,1)nonan-2-one was originally thought to be difficult to synthesize, two different methods (DCC and di-n-butyltin oxide) will produce it with high yield. DCC is a strong reagent for absorbing water; the di-n-butyltin oxide method uses a Dean-Stark to remove water and is very useful. Bredt's rule influences the synthesis and stability of the N-bridgehead bicyclic lactams, this is apparent in the lactam series in the behavior of the (2,2,2) compounds and the (3,2,1) compound which we tried unsuccessfully to synthesize.


Apap: The Arithmetic Pipeline Analysis Package, Chang-Chieh Lin May 1988

Apap: The Arithmetic Pipeline Analysis Package, Chang-Chieh Lin

Theses

This study is aimed at the development of an interactive PC-based package for simulating data flow within an arithmetic pipeline in multiprocessor systems. The user constructs the arithmetic pipeline, specifying the functionality of each segment, the intersegment connectivity and pipeline inputs and outputs. After defining reservation tables and data, analysis is performed with the results available in tabular, simple graphic and animated graphic forms.

APAP allows the user to design hardware and analyze its functionality with-out building the circuit, an economical alternative. Even when circuits are to be built, APAP allows the user to correct logic errors before implementation, leaving …


The Quantitative Determination Of Formaldehyde In Ambient Air (Analytical Method), Chitsan Lin May 1988

The Quantitative Determination Of Formaldehyde In Ambient Air (Analytical Method), Chitsan Lin

Theses

A procedure for coating in situ silica gel in prepacked cartridges with 2,4-dinitrophenylhvdrazine (DNPH) acidified with hydrochloric acid is described. The method was evaluated under practical field conditions in The Northern New Jersey-Staten Island Urban Air Toxics Project. The formaldehyde hydrazone formed is desorbed by acetonitrile and determined by high-performance liquid chromatography with UV det.ection. In this study, we have examined trap coaz)ng, trap efficiency, parallel ambient air and inaoor air sampLing, to find the best analysis method. Sampling traps aci:iifled .:ith hydrochloric acid perform better than those using percnicric acid or phosphoric acid. Trap sampling efficiency was significantly affected …


An Analysis Of The Second-Order, Type-One Hilbert Phase-Locked Loop, Inn-Shian Lin May 1988

An Analysis Of The Second-Order, Type-One Hilbert Phase-Locked Loop, Inn-Shian Lin

Theses

In this thesis, a second-order, type-one PLL ( Phase- Lock, Loop ) in which the usual lead-lag loop filter is paralleled with a Hilbert Transformer (the whole system is called HPLL) is analyzed. A motivation for the study was that earlier researchers have found improved performance if Ilse lead-lag network is paralleled by a differentiator, result mg in the so called ERPIM (Extended-Range Phase-Locked Demodulator). For the purpose of com-parison with earlier experimental and analytical results on the PLL and the ERPLD, the numerical results in this thesis ale based on the parameters of Acampora and Newton.

The basic characteristics …


Simulation Study Of The Multi-H Continuous Phase Modulation, Min-Ling Lin May 1988

Simulation Study Of The Multi-H Continuous Phase Modulation, Min-Ling Lin

Theses

Of particular interest in satellite communications are modulation techniques that have a relatively constant envelope and are power and bandwidth efficient. Attempts have been made to satisfy these requirements by using phase and frequency modulation formats. Recently, one approach has been researched which combines the modulation and encoding functions, which is referred to as multi-h continuous phase modulation. Simultaneously good power and bandwidth efficiencies can be achieved at the expense of increased complexity.

This report examines the performance of multi-h continuous phase modulation by a simulation. A multi-h phase coded modulation is generated, passed through the AWGN transmission channel. The …


High Frequency Gaussian Beams Solution Of A Plane Wave Coupling Into Cylindrical Cavity, Christine Issa Mourad May 1988

High Frequency Gaussian Beams Solution Of A Plane Wave Coupling Into Cylindrical Cavity, Christine Issa Mourad

Theses

Propagation of high frequency fields as a superposition of Gaussian beams instead of geometrical ray fields has potential advantages in complicated environments because the beams do not fail in ray optic transition regions. While the Gaussian beam method can be made rigorous through self consistent stacking of displaced and tilted beams on a Gabor phase space lattice, with retention of full beam spectra, computation is facilitated when the propagation domain is covered with paraxially approximated nontilted beams. The spectral deficiencies introduced by this simplified propagation model depend on the propagation environment. They are examined here for a plane wave coupling …


Computer Aided Synthesis Of A Four-Bar Linkage To Generate A Symmetrical Coupler Curve, Shailendra R. Pachalag May 1988

Computer Aided Synthesis Of A Four-Bar Linkage To Generate A Symmetrical Coupler Curve, Shailendra R. Pachalag

Theses

The purpose of this study is to develop a new analytical technique for the synthesis of four-bar mechanisms to generate symmetrical curves with a coupler point passing through 8 points. The geometric expressions involved in kinematic synthesis often tend to offer difficulties such as negative radicals, alternative choices and repetitions. Here a solution procedure has been developed which avoids these difficulties. This solution procedure includes a development of a computer algorithm that should synthesize a crank-rocker type linkage for any given input crank length. This algorithm dismisses all solutions involving negative radicals and lists magnitudes of members so that those …


Design Criteria Of Coherent Optical Fiber Communication System, Rajesh N. Patel May 1988

Design Criteria Of Coherent Optical Fiber Communication System, Rajesh N. Patel

Theses

Design criteria of coherent optical fiber communication system were discussed and investigated. First, the different types of optical fibers (waveguides) were discussed. Then the laser sources, photo-detectors, transmitter & receiver circuits were discussed in detail.

Design criteria of conventional intensity modulated (direct detection) optical fiber communication system were discussed. Then, the design criteria and estimation of number of photons for different modulation schemes for coherent optical fiber communication system were analyzed.

Coherent optical fiber communication system's advantages and drawbacks were discussed in detail. Improvement in receiver sensitivity of coherent detection compare with conventional direct detection was investigated. Finally, some receiver …


Image Enhancement And Edge Detection Using Fuzzy Algorithm, Samir Patel May 1988

Image Enhancement And Edge Detection Using Fuzzy Algorithm, Samir Patel

Theses

A method of image enhancement and edge detection by computer using the fuzzy set is illustrated. The algorithm involves extraction of fuzzy properties corresponding to pixels and then succesive application of fuzzy operator 'contrast intensification' along with smoothing in the fuzzy property plane before detecting its edges. The property plane is extracted from the spatial domain using S, π, and (1- π) functions and the fuzzifiers. Edge detection is achieved using KIRSH operator. A computer routine is developed and the effectiveness of the algorithm with different value of the system parameter is demonstrated on different images. The digital computer HP …


Design And Construction Of A Thermoelectric Calorimeter To Measure Thermal Resistance Of Building Components, Ravindra Samtaney May 1988

Design And Construction Of A Thermoelectric Calorimeter To Measure Thermal Resistance Of Building Components, Ravindra Samtaney

Theses

The steady-state thermal resistance of a building wall is an important parameter in determining its thermal performance. In-situ measurement of thermal resistance is the only unambiguous way of determining thermal resistance since the actual value may significantly differ from the laboratory or the calculated R-value.

Hitherto, the in-situ measurement of thermal resistance has been largely confined to the winter season. A thermoelectric calorimeter was designed, constructed and tested in order to provide measurements of thermal resistance during the summer as well as the winter season.

This thermoelectric calorimeter is a rectangular box, insulated on five sides and covered with an …


Design Of An Experimental Apparatus To Measure The Charge And Mass Of Ionized Species In A Partially Ionized Cluster Beam Deposition System, Nitin K. Shah May 1988

Design Of An Experimental Apparatus To Measure The Charge And Mass Of Ionized Species In A Partially Ionized Cluster Beam Deposition System, Nitin K. Shah

Theses

The objective of this research was the design and construction of an experimental apparatus to investigate the size distribution of gallium clusters that can be emitted from a heated crucible with a 1 mm nozzle. This research work involved the design and construction of a partially ionized cluster beam (PICB) deposition system which would provide low charged particle background for retarding field analysis and cluster size measurements. The apparatus also allowed control of critical parameters on which the cluster size may depend.

The promise of PICB is based on the formation of clusters of adatoms, their ionization and their acceleration …


Investigation Of High Shear-Rate Viscoelastic Flow, Sudarshan S. Sood May 1988

Investigation Of High Shear-Rate Viscoelastic Flow, Sudarshan S. Sood

Theses

The object of this study is to understand two important characteristics exhibited by viscoelastic fluids at high shear-rates, and analyse their influence on practical applications Viscoelastic fluids, such as polymer solutions, when subjected to high shear stress, behave in a manner which has not been sufficiently analytically explained In experimental studies, such fluids have shown.

(a) Stress relaxation.

(b) Decrease of viscosity with an increase in shear rate.

(c) Slight decrease of viscosity with temperature.

(d) Normal stress differences in shear flow.

In this thesis an analytical explanation is given for two (a and b ) of these features This …


Friedman's Model Of Calculating The Optimum Bid Price Using Dbase Iii Plus, Selim Uzel May 1988

Friedman's Model Of Calculating The Optimum Bid Price Using Dbase Iii Plus, Selim Uzel

Theses

The micro-computer program, BIDCALC presented in this thesis is offered as simple, practical, and proven approach to developing an effective data-based competitive bidding strategy. BIDCALC is written in dBASE III Plus programming language for MS-DOS based computers.

Main purpose of the program is to evaluate the optimum bid using the Friedman's model of Maximizing the Expected Profit. At the same time the program keeps track of necessary competitor and project information in data base files which are easily transferable to other software packages. The program is capable of generating a variety of reports in a matter of seconds.

BIDCALC is …


Automatic Generation Of Robot Paths For Waterjet Cutting From Autocad Drawings, Samir Vij May 1988

Automatic Generation Of Robot Paths For Waterjet Cutting From Autocad Drawings, Samir Vij

Theses

The automatic generation of robot paths for a commercial water-jet cutting system by establishing a link with a commercial CAD system, in an attempt to achieve paper-less manufacturing and to minimize human interface is the objective of this thesis.

Water-jet cutting is an emerging technology with unlimited potential for a wide variety of manufacturing applications. Water-jet cutting systems integrated with robotic work cells allow the user to cut a variety of parts through part programs generated for robot controllers. The system employed is an Ingersoll-Rand water-jet cutting system, the movement of which is controlled by an Allen-Bradley 8200R programmable robot …


Investigation Of The Characteristics Of The Kerf And The Surface Generated In The Course Of Cutting Titanium With Abrasive Waterjets, Ajay Vora May 1988

Investigation Of The Characteristics Of The Kerf And The Surface Generated In The Course Of Cutting Titanium With Abrasive Waterjets, Ajay Vora

Theses

The effect of cutting parameters on the quality of cut in the course of cutting Titanium (Gr.2) with Abrasive Waterjet is investigated. The cutting parameters include nozzle traverse rate, size and feed rate of abrasives and nozzle(s) diameter. The width of kerf (top and bottom ), taper and roughness is studied. The measurements are tabulated and plots are made to study the trend and relationship for each set of parameters.

The qualitative conclusions are made successfully but no quantitative relationship was derived. Suggestions are made for the evaluation of technology for feasibility and economic justification, and to achieve desired cutting …


Rf Characterization Of A Directly Modulated Ingaasp Buried Heterostructure Laser Diode, Charlotte Alvarez May 1988

Rf Characterization Of A Directly Modulated Ingaasp Buried Heterostructure Laser Diode, Charlotte Alvarez

Theses

The use of fiber optics for the transmission of microwave signals had its beginnings in 1984. Applications were limited to the lower microwave frequency regions. Technology in this field is advancing rapidly due to the high demand driven by the telecommunications community for high speed digital applications. Extensive research and development efforts are underway by both the component manufacturers and the subsystem end user. Most of the near term applications of microwaves in fiber optics are in weapon systems and communication systems for military and other government agencies.

The high frequency modulation characteristics of Lytel's InGaAsP 1300 nm buried heterostructure …


Design Of Bridge Inter-Connecting Token Ring & Token Bus Local Area Networks, Kasinath Anupindi May 1988

Design Of Bridge Inter-Connecting Token Ring & Token Bus Local Area Networks, Kasinath Anupindi

Theses

A Bridge interconnecting two Local Area Networks has been modelled. The two interconnected networks are the Token Ring and the Token Bus LANs. Concepts of Queueing theory have been employed in the design. Initially it is assumed that the buffer size at the Bridge is infinite. Further it is assumed that the arrival rate of the messages is Markovian and the service rate is General, Le it is an M/G/1 system. Expressions for the average waiting time at the Bridge and the size of the buffers is computed. Graphs for various parameters have been plotted. Based on these graphs the …


A 3-D Tactile Sensor With Digital Output, Sin-Shou Cho May 1988

A 3-D Tactile Sensor With Digital Output, Sin-Shou Cho

Theses

This thesis details the design of a new tactile sensor for general-purpose robot manipulators. Such manipulators, designed to be functionally equivalent to the human hand, will require sensor arrays that fulfill several requirements : (1) many sensor elements to minimize tactile imaging time, (2) close spacing of small sensing elements for fine spatial discrimination, (3) ability to be molded to a convex fingertip surface for taction on concave surfaces, (4) tolerance to over-scale forces without damage. In addition to the above, which are considered requirements, several other characteristics are desirable. Foremost is the ability to sense shear forces, which provide …


Estimation Of Modified Proctor Densities Based On Visual Identification, Ramesh Damodaram May 1988

Estimation Of Modified Proctor Densities Based On Visual Identification, Ramesh Damodaram

Theses

Often in construction jobs requiring controlled compaction, there is a delay involved in testing the soil sample to be used as a structural fill. Here a rational approach has been adopted to get these values from 600 test data available. Using these data, appropriate relationships between grain sizes, maximum dry densities and optimum moisture content were developed. From these, two tables were derived to estimate the maximum dry density and optimum moisture content based on grain size distribution.

In a fill control job, if the borrow pit happens to change, the field personnel could obtain soil samples and send them …


Implementation Of The Voice Processing System, Yang-Young Dan May 1988

Implementation Of The Voice Processing System, Yang-Young Dan

Theses

The Voice Processing System is implemented by using XILINX Advanced Computer Aided Design Technology. It is also used as an interface to the 8052 AH-BASIC single hoard computer system.

The Voice Processing System ( VPS ) comprises three major parts:

1. Voice Detection Circuit

2. System Clock Generation & Synchronization

3. Signal Processing and Storing Circuit

The analog voice sip!gnals are the inputs to the first part of VPS. The digitalized voice is the output of this system.

In order to get precise output, the first part plays the roles of noise cancellation, zero crossing processing, and recognition.

For the …


Messaging, The Effects Of The Use Of Voice Mail On The Use Of Electronic Mail, Terese M. De Troia May 1988

Messaging, The Effects Of The Use Of Voice Mail On The Use Of Electronic Mail, Terese M. De Troia

Theses

A number of office automation products have evolved over the years to address the messaging needs of organizations. The 1800's brought us telegraph systems which led the way for teletype and Telex systems, followed by facsimilie, computer-based message systems, document based electronic mail and, most recently, voice store and forward (or voice messaging) systems (Advances in Office Automation, 1985). Voice messaging systems, a newly emerging method of communications, are having a significant impact on communications. The concept of messaging services is rapidly gaining acceptance in business communities (Girishankar 1986, Hirschheim 1985). With costs rising and time becoming more valuable, organizations …


Two Domain Heat Transfer Studies Using A Coupled Finite-Difference And Boundary Element Programs, Serap Dikmenli May 1988

Two Domain Heat Transfer Studies Using A Coupled Finite-Difference And Boundary Element Programs, Serap Dikmenli

Theses

An iterative coupling of a finite-difference boundary layer code "STAN5"' and a boundary element code "BEASY"2 have been used to study two dimensional convective-conductive problems. The coupling method essentially leaves undisturbed the codes of these programs and uses their custom features in their applicable domains. The boundary layer program is used-in the convective domain, while "BEASY" is used in the solid domain. Compatability conditions are established between these domain solutions and an iterative scheme is used until these conditions are mutually satisfied.

The indirect communication of compatability (boundary) criteria between these programs was achieved by two editor/data-transferor like programs. Combined …