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A Simulation Study Of A Limited Sensing Random Access Algorithm For A Local Area Network With Voice Users, Robert M. Spillers Jan 1987

A Simulation Study Of A Limited Sensing Random Access Algorithm For A Local Area Network With Voice Users, Robert M. Spillers

Retrospective Theses and Dissertations

The purpose of this work is to evaluate the perfonnance of a limited sensing random access algorithm in a local area network with voice users. Random access algorithms have proven to be very efficient in local area network environments with data users. However, in contrast to data packets, voice packets cannot be allowed to experience long delays, because of the requirement that a voice "data stream" must be played out at the receiver. If a voice packet does exceed its established maximum delay, it is discarded. This simulation study finds the number of voice users that a network can support, …

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Bias Optimization For Noise Reduction In Focal Plane Arrays, Kirk B. Reiff Jan 1987

Bias Optimization For Noise Reduction In Focal Plane Arrays, Kirk B. Reiff

Retrospective Theses and Dissertations

A gain enhanced common gate transresistance circuit is typically used as the coupling circuit between detector and multiplexer in a focal plane array. At an operating temperature of 77 degrees Kelvin, the dominant noises in the system are shot noise and 1/f noise. The 1/f noise corner frequency of the CMOS amplifiers used in focal plane arrays can .be as high as 10 kHz. In this paper it is shown that the 1/f noise corner frequency contributed to the system noise by the amplifier is a function of the bias voltage applied to the photodiode detector. Specifically, as the reverse …

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Fibergramme Vol.11 No. 1, Weavers Of Orlando Jan 1987

Fibergramme Vol.11 No. 1, Weavers Of Orlando

Text Materials of Central Florida

FIBERGRAMME is published in September, November, January, March and May.

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Fibergramme Vol.11 No. 2, Weavers Of Orlando Jan 1987

Fibergramme Vol.11 No. 2, Weavers Of Orlando

Text Materials of Central Florida

FIBERGRAMME is published in September, November, January, March and May.

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Fibergramme Vol.11 No. 6, Weavers Of Orlando Jan 1987

Fibergramme Vol.11 No. 6, Weavers Of Orlando

Text Materials of Central Florida

FIBERGRAMME is published in September, November, January, March and May.

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Fate Map Of The Eye Antennal Imaginal Disk Of The Tumorous-Head Mutant Of Drosophila-Melanogaster, Deborah J. Andrew Jan 1987

Fate Map Of The Eye Antennal Imaginal Disk Of The Tumorous-Head Mutant Of Drosophila-Melanogaster, Deborah J. Andrew

Faculty Bibliography 1980s

In specific genetic backgrounds, a mutation in the tuh-3 gene results in the homeotic transformation of head structures to either leg disc derivatives or structures normally found in the extreme posterior end of wild-type animals. The origins of the homeotic structures were mapped to defined positions in the eye-antennal imaginal disc by transplanting abnormal regions of discs isolated from tuh-3 mutants into host mwh;e4 larvae. These metamorphosed implants were removed and differentiated structures were identified. Of 211 successfully recovered implants, 157 gave rise to homeotic tissue: abdominal tergite, male or female external genitalia and/or leg tissue. Transformations to abdominal tergite …

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Fourier Spectrum Techniques For Characterization Of Spatial Noise In Imaging Arrays, Glenn D. Boreman Jan 1987

Fourier Spectrum Techniques For Characterization Of Spatial Noise In Imaging Arrays, Glenn D. Boreman

Faculty Bibliography 1980s

Noise performance in imaging arrays is often specified simply by the variance of the pixel levels. In this paper a more complete characterization technique is presented, based on the spatial-frequency power spectrum of the noise data on the detectors. This is seen to provide additional information for cases in which the noise spectrum is nonwhite. Experimental data demonstrate the nonwhite nature of the spectrum under certain conditions, especially resulting from spatial correlation of detector nonuniformity and from sampling-lattice-related artifacts in the data.

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Compensation For Gain Nonuniformity And Nonlinearity In Hgcdte Infrared Charge-Coupled-Device Focal Planes, Glenn D. Boreman, Christopher Costanzo Jan 1987

Compensation For Gain Nonuniformity And Nonlinearity In Hgcdte Infrared Charge-Coupled-Device Focal Planes, Glenn D. Boreman, Christopher Costanzo

Faculty Bibliography 1980s

Infrared CCD arrays generally require a compensation for the effect of gain and offset variation among the individual detectors of the array. Linear compensation techniques do not suffice for focal planes that exhibit a large nonlinearity of response combined with order-of-magnitude variations in threshold and saturation flux levels. This situation is common among hybrid architecture CCDs, particularly when HgCdTe is the detector material. This paper reports on a multipoint piecewise-linear correction scheme employed on a HgCdTe infrared CCD focal plane. This technique allows a compensated response to be obtained in a computationally efficient manner. An experimental relationship between the number …

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Crummer Graduate School, Rollins College Jan 1987

Crummer Graduate School, Rollins College

Text Materials of Central Florida

Rollins College catalogue with list of faculty and students and courses by department.

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Rollins College Catalogue, 1987-1988, Rollins College Jan 1987

Rollins College Catalogue, 1987-1988, Rollins College

Text Materials of Central Florida

Rollins College catalogue 1987-1988 with list of faculty and students and courses by department.

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Rollins College Winter Term 1987, Rollins College Jan 1987

Rollins College Winter Term 1987, Rollins College

Text Materials of Central Florida

Rollins College catalogue with list of faculty and students and courses by department.

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Doppler-Free Polarization Spectroscopy Of The B1-Pi-U-X1-Sigma-G+ Band System Of K-2, J. Heinze, U. Schühle, F. Engelke, C. D. Caldwell Jan 1987

Doppler-Free Polarization Spectroscopy Of The B1-Pi-U-X1-Sigma-G+ Band System Of K-2, J. Heinze, U. Schühle, F. Engelke, C. D. Caldwell

Faculty Bibliography 1980s

No abstract provided.

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Mathematical Modeling Of Continuous Dynamic Systems, Harold H. Klee Jan 1987

Mathematical Modeling Of Continuous Dynamic Systems, Harold H. Klee

Faculty Bibliography 1980s

Mathematical models of physical systems assume several forms depending on their intended use. This paper illustrates the use of a nonlinear and linear model to describe the dynamic response of a particular physical system. A block oriented simulation program, TUTSIM, is presented as the vehicle for obtaining approximate solutions of the nonlinear model. Analytical solution of the small signal linear model is compared to the nonlinear simulation results.

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Strong Correlation And Alignment Near The Be 1s Photoionization Threshold, Manfred O. Krause, C. Denise Caldwell Jan 1987

Strong Correlation And Alignment Near The Be 1s Photoionization Threshold, Manfred O. Krause, C. Denise Caldwell

Faculty Bibliography 1980s

Photoionization in atomic beryllium has been studied in detail near the 1 s threshold. Multiple excitation to the 1 s ( 2 s 2 p 1 , 3 P ) states, i.e., conjugate shakeup, is found to be unusually strong, 40% of single excitation. The 3 P component rapidly loses strength with increasing photon energy, while the 1 P component persists. The 1 s 2 s 2 p states are highly aligned, as shown by the Auger-electron angular distribution. The A 2 value of -0.65 implies a d -wave contribution of 0.39. Our results indicate that resonances reported for the …

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Magnetic Reconnection Induced By Perturbation On Boundaries, Bhimsen K. Shivamoggi Jan 1987

Magnetic Reconnection Induced By Perturbation On Boundaries, Bhimsen K. Shivamoggi

Faculty Bibliography 1980s

The magnetic field reconnection is considered in a plasma induced by perturbing the boundaries of a slab of incompressible plasma with a magnetic neutral surface inside. It is assumed that the boundaries of the plasma slab are perturbed at both fast and slow rates compared with the hydromagnetic evolution rate, and the ensuing adjustments in the plasma and the magnetic field threading through it are investigated.

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Maximum Entropy Reconstruction Of Moment Coded Images, Nicolaos S. Tzannes, Peter A. Jonnard Jan 1987

Maximum Entropy Reconstruction Of Moment Coded Images, Nicolaos S. Tzannes, Peter A. Jonnard

Faculty Bibliography 1980s

The maximum entropy principle (MEP) is applied to the problem of reconstructing an image from knowledge of a finite set of its moments. This new approach is compared to the existing method of moments approach and is shown to have a clear edge in performance in all of the applications attempted. Compression ratios more than twice as high as those previously achieved are possible with the new MEP method.

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Preparation Of Geminal Diflourodienes, Antonio Landavazo Jan 1987

Preparation Of Geminal Diflourodienes, Antonio Landavazo

Retrospective Theses and Dissertations

This report discusses research involving the preparation of germinal difluorodienes. Free radical addition of dibromodifluoromethane to 1-hexene and cyclohexene was performed, followed by a double dehydrohalogenation to yield 1,1-difluoro-1,3-heptadiene and 3-(difluoromethylene)cyclohexene, respectively. NMR, IR, and mass spectral data were obtained and presented as groundwork for further research. A study comparing the free radical initiators, benzoyl peroxide and 2,2’-azobis-(2-methyl)proprionitrile (AIBN) was included, showing neither as ideal initiators for the free radical additions performed. The relative stabilities of the bromodifluoromethyl and the difluoroiodomethyl radicals were approximated. A Diels-Alder reaction of 1,1-difluoro-1,3-heptadiene with 4-phenyl-1,2,4-triazoline-3,5-dione produced the expected [4 + 2] cycloadduct in good …

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Hydration Of Propylene To Isopropanol, Nehemiah Diala Jan 1987

Hydration Of Propylene To Isopropanol, Nehemiah Diala

Retrospective Theses and Dissertations

The hydration of propylene to isopropanol was investigated. The first part of this study concerned the direct hydration reaction in various liquid phase systems in the presence of sulfuric acid or p-toluenesulfonic acid. The second part in a two-stage process in which propylene was contacted with excess acetic acid to form isopropyl acetate; the ester was then hydrolyzed to isopropyl alcohol and acetic acid.

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The Reaction Of 2-Arylprop-1-En-3-Yltrimethylammonium Iodides With Sulfur Nucleophiles And Useful Synthetic Applications Of These Adducts, Steven J. Duranceau Jan 1987

The Reaction Of 2-Arylprop-1-En-3-Yltrimethylammonium Iodides With Sulfur Nucleophiles And Useful Synthetic Applications Of These Adducts, Steven J. Duranceau

Retrospective Theses and Dissertations

This report discusses research involving the reactions of 2-arylprop-1-en-3-yltrimethyl ammonium iodides with sulfur nucleophiles and the useful synthetic applications of the adducts formed. The present work may be subdivided into four sections: 1) reactions of several 2-arylprop-1-en-3-yltrimethylammonium iodides with benzenethiol; 2) reactions of several 2-arylprop-1-en-3-yltrimethylammonium iodides with the sodium salt of benzenesulfinic acid; 3) reactions of several 2-arylprop-1-en-3-yltrimethylammonium iodides with 2-mercapto-1-methyl imidazole; and 4) oxidation of 2-aryl-3-phenylthio-1-propenes and 2-aryl-3-phenylsulfonyl-1-propenes using sodium perborate. This report outlines the experimental conditions and procedures responsible for the synthesis of these products; in addition, this report describes the physical properties, NMR and IR spectra of …

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The Slicing Extent Technique For Fast Ray Tracing, Sudhanshu Kumar Semwal Jan 1987

The Slicing Extent Technique For Fast Ray Tracing, Sudhanshu Kumar Semwal

Retrospective Theses and Dissertations

A new technique for image generation using ray tracing is introduced. The “Slicing Extent Technique” (SET) partitions object space with slicing planes perpendicular to all three axes. Planes are divided into two dimensional rectangular cells, which contain pointers to nearby objects. Cell size and the space between slices varies, and is determined by the objects’ locations and orientations. Unlike oct-tree and other space-partitioning methods, SET is not primarily concerned with dividing space into mutually exclusive volume elements (‘voxels’) and identifying objects within each voxel. Instead, SET is based on analysis of projections of objects onto slicing planes. In comparison to …

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Person Perception And The Employment Interview: The Impact Of Facial Features In The Employee Selection Process, Susan C. Muller Jan 1987

Person Perception And The Employment Interview: The Impact Of Facial Features In The Employee Selection Process, Susan C. Muller

Retrospective Theses and Dissertations

Previous research has found that the structural makeup of the face influences the manner by which individuals perceive others and attribute characteristics to them. In addition, support has been provided for the hypothesis that nonverbal cues significantly influence an interviewer's perception of a job candidate and the pending hiring decision. Taken together, this study hypothesized that the nonverbal cues emitted from the structural makeup of the face would impact the decision to hire and the perceptions of the job applicant's personality. It was also expected that variations in facial structure would influence an employer's decision in hiring the applicant for …

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Design And Performance Analysis Of A Relational Replicated Database Systems, Jon Gregory Hanson Jan 1987

Design And Performance Analysis Of A Relational Replicated Database Systems, Jon Gregory Hanson

Retrospective Theses and Dissertations

The hardware organization and software structure of a new database system are presented. This system, the relational replicated database system (RRDS), is based on a set of replicated processors operating on a partitioned database. Performance improvements and capacity growth can be obtained by adding more processors to the configuration. Based on designing goals a set of hardware and software design questions were developed. The system then evolved according to a five-phase process, based on simulation and analysis, which addressed and resolved the design questions. Strategies and algorithms were developed for data access, data placement, and directory management for the hardware …

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Job Characteristics Model: Test Of A Modified Four-Trait Model At The University Of Central Florida, Gena L. Cox-Jones Jan 1987

Job Characteristics Model: Test Of A Modified Four-Trait Model At The University Of Central Florida, Gena L. Cox-Jones

Retrospective Theses and Dissertations

The study examined the number of significant factors in the Hackman and Oldham (1980) job characteristics model. The original factors were: Skill Variety, Task Significance, Task Identity, Autonomy, and Feedback. Scores on these dimensions for 84 employees of the University of Central Florida (21 supervisory and 63 non-supervisory subjects) were used as the basis for this study through a mail administration of the Hackman and Oldham Job Diagnostic Survey (JDS) and their Job Rating Form (JRF). It was hypothesized that: (a) only four significant job dimensions would emerge from factor analysis of the data; (b) that the motivating potential ratings …

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Marksmanship Performance With The M16a1 Rifle As A Function Of Physical Fitness, Heart Rate, And Exercise Intensity, Jeffrey B. Cuddeback Jan 1987

Marksmanship Performance With The M16a1 Rifle As A Function Of Physical Fitness, Heart Rate, And Exercise Intensity, Jeffrey B. Cuddeback

Retrospective Theses and Dissertations

Fifty-two rifle naïve navy personnel underwent four days of simulated M16A1 live fire training in an artificial intelligent test bed trainer, followed by one day of live fire record qualification in the field. Prior to test bed training, subjects were administered the Army Physical Readiness Test (APRT) and assessed on their current level of physical fitness. At the end of test bed training the subjects participated in one of four exercise conditions (control, walk, job, or run) designed to elevate their hart rates. Immediately following exercise they shot a 10 round self-paced task at a scaled 250 meter target. Analysis …

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The Effects Of Locus Control Upon Pay Satisfaction, Richard A. Curle Jan 1987

The Effects Of Locus Control Upon Pay Satisfaction, Richard A. Curle

Retrospective Theses and Dissertations

The issue of pay satisfaction is of increasing concern to management because of today's high cost of recruiting and training employees. Also of concern to management is the impact that a high employee turnover rate, due to pay dissatisfaction, can have on organizational effectiveness. Therefore, identifying the causes of, and reducing the probability of, employee pay dissatisfaction is desirable.

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Evaluation Of Concrete Pavement Performance With Related Cracking And/Or Voids Under I-10 Concrete Pavement, Cecil R. Henderson Jan 1987

Evaluation Of Concrete Pavement Performance With Related Cracking And/Or Voids Under I-10 Concrete Pavement, Cecil R. Henderson

Retrospective Theses and Dissertations

Under existing concrete highway payments there are voids that develop because of the pumping action of the slabs. The presence of free water, curled slabs from temperature and moisture gradients, and heavy wheel loads combine to provide this problem. The result is pumping and erosion of the base material, nonuniform support of the pavement slab, and eventual breakup of the concrete slabs. Two methods of voids detection were utilized in this study to compare one against the other. The first method used the Falling Weight Deflectometer (FWD) and the second method used the Ground Penetrating Radar (GPR) unit. Deflection readings …

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Applications Of Simulation And Animation In Facilities Planning And Design, William Joseph Mattingly Jan 1987

Applications Of Simulation And Animation In Facilities Planning And Design, William Joseph Mattingly

Retrospective Theses and Dissertations

Recent developments of simulation software have made computer simulation and animation popular system problem-solving techniques. One field that has many potential applications for computer simulation and animation is in the area of facilities planning and design. The purpose of this paper is to provide the facilities planner with information to assist in determining when, why, how and what simulation software should be implemented to solve facilities planning and design problems. Also, the usefulness of simulation and animation to the facilities planner is evaluated and areas for improving software for future application in facilities planning and design are identified. TO assist …

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A Rapid Acquisition Technique For Direct Sequence Spread Spectrum Systems By A Pn Phase Multiplexed Correlator, Greg S. Rawlins Jan 1987

A Rapid Acquisition Technique For Direct Sequence Spread Spectrum Systems By A Pn Phase Multiplexed Correlator, Greg S. Rawlins

Retrospective Theses and Dissertations

With the proliferation of direct sequence spread spectrum (DSSS) systems in the communications arena, synchronization techniques that offer improved performance and higher speed are of great value to the spread spectrum designer and user. Matched filter approaches have gained momentum in recent years due to SAW filter technology, while sliding correlators have experienced slower development. This paper introduces a unique multi-phase correlator intended to decrease the mean time to acquire synchronization by exploiting properties of Gold codes and other pseudo-noise (PN) sequences. These properties are used to create a novel signal structure for the local correlator. A brief explanation of …

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Extending The Power Bandwidth Of A Piezoelectric Bender Actuator, Jerrold Pavlinko Jan 1987

Extending The Power Bandwidth Of A Piezoelectric Bender Actuator, Jerrold Pavlinko

Retrospective Theses and Dissertations

Scanning mirrors are a control element used in electrooptical systems. A scanning mirror system is a position control system that directs an image to an optical receiver or projects the output of an optical source to a target. A scanning mirror, as part of an infrared image generation system, could be used to scan an array of infrared detectors with a television camera to produce a raster image. Conversely, a scanning mirror could be part of a laser engraving system where the mirror moves the laser beam across the surface of a material to engrave characters, drawings in the material.

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Implementing Path Control, English Motion Commands And Off Line Programming On Minimover-5 Robot, Mark S. Chen Jan 1987

Implementing Path Control, English Motion Commands And Off Line Programming On Minimover-5 Robot, Mark S. Chen

Retrospective Theses and Dissertations

According to Alan L. Porter and Frederick A. Rossini (1987), 50,000 robots are expected to be installed by year 2000. This increasing number of robots to be used in industry has lead to the need for skilled robot operators and programmers. However, to train this specific class of personnel using an industrial robot as a training tool can be expensive and dangerous due to the possibility of robot accidents. Therefore, in order to provide a safe, inexpensive, and effective training tool, the use of the Mini-Mover-5 educational robot is proposed. The MiniMover-5 has only a primitive programming capability. A use-friendly …

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