Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

1995

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 1321 - 1350 of 2193

Full-Text Articles in Physical Sciences and Mathematics

State Of Tampa Bay 1994, Tampa Bay Regional Planning Council (Tbrpc), Agency On Bay Management Feb 1995

State Of Tampa Bay 1994, Tampa Bay Regional Planning Council (Tbrpc), Agency On Bay Management

Reports

This is the eighth "State of Tampa Bay" report on the projects, programs and organizations that influence the Bay and its watershed . This status report identifies the condition of Tampa Bay over the past year and describes activities and issues addressed by the Tampa Bay Regional Planning Council's Agency on Bay Management during 1994. It was prepared in accordance with the adopted rules of the Agency , and this year is sponsored, in part, by the Tampa Bay National Estuary Program.


The Orbital Period Of The Pre-Cataclysmic Binary Re 2013+400 And A Study Of The Atmosphere Of The Dao White Dwarf Primary, M. A. Barstow, M. R. Burleigh, T. A. Fleming, J. B. Holberg, D. Koester, M. C. Marsh, S. R. Rosen, R. G.M. Rutten, S. Sakai, R. W. Tweedy, G. Wegner Feb 1995

The Orbital Period Of The Pre-Cataclysmic Binary Re 2013+400 And A Study Of The Atmosphere Of The Dao White Dwarf Primary, M. A. Barstow, M. R. Burleigh, T. A. Fleming, J. B. Holberg, D. Koester, M. C. Marsh, S. R. Rosen, R. G.M. Rutten, S. Sakai, R. W. Tweedy, G. Wegner

Dartmouth Scholarship

Several pre-cataclysmic binaries, comprising a hot white dwarf with a red dwarf companion, have been discovered as a result of the optical identification of EUV sources from the ROSAT all-sky survey. The optical spectra have the steep blue continuum and Balmer absorption typical of a hot white dwarf, but there are bright, narrow emission lines of H I (and sometimes He I and Ca II) superimposed. An intense campaign of follow-up observations has been devoted to these binary systems. So far, only RE 2013+400 has exhibited any measurable changes in the radial velocities of the emission components, from which it …


A Study Of D*+ Π- Production In Semileptonic B Decay, D. Buskulic, M. Thulasidas Feb 1995

A Study Of D*+ Π- Production In Semileptonic B Decay, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

In a sample of 1.5 million hadronic decays of the Z collected by the ALEPH detector, a search is carried out for the decays B→ D10(2420)l−νX and B→ D2∗0(2460)l−νX. The product branching ratio for D10 production is measured to be Br(b →B) × Br(B→ D10l−νX) × Br(D10→ D∗+π−) = (2.04 ± 0.58stat± 0.34syst) × 10−3, and a 95% confidence level limit of Br(b →B) × Br(B→ D2∗0l−νX) × Br(D2∗0→ D∗+π−) ≤ 0.81 × 10−3 is obtained for D2∗0 production.A topological search sensitive to the processes above, but also to wide resonances that decay to D∗+π− and to non-resonant D∗+π− production …


Coherent Control Of H- Photodetachment In Parallel Static Electric And Magnetic Fields, Qiaoling Wang, Anthony F. Starace Feb 1995

Coherent Control Of H- Photodetachment In Parallel Static Electric And Magnetic Fields, Qiaoling Wang, Anthony F. Starace

Anthony F. Starace Publications

Theoretical calculations of quantum interference effects occurring in photodetachement of H- with short-pulse lasers in the presence of a uniform static electric field [Q. Wang and A. F. Starace, Phys. Rev. A 48, R1741 (1993)] are examined in more detail and extended to the case of parallel static electric and magnetic fields. We show that modulation factors characterizing near-threshold cross sections resulting from detachment by relatively long laser pulses may be employed to set the parameters that are most effective for control of detachment cross-section magnitudes with short coherent laser pulses. Use of a static magnetic field to control detached …


Design And Performance Of The Advanced-Light-Source Double-Crystal Monochromator, G. Jones, S. Ryce, Dennis W. Lindle, B. A. Karlin, J. C. Woicik, Rupert C. Perera Feb 1995

Design And Performance Of The Advanced-Light-Source Double-Crystal Monochromator, G. Jones, S. Ryce, Dennis W. Lindle, B. A. Karlin, J. C. Woicik, Rupert C. Perera

Chemistry and Biochemistry Faculty Research

A new “Cowan type” double-crystal monochromator, based on the boomerang design used at National Synchrotron Light Source (NSLS) beamline X-24A, has been developed for beamline 9.3.1 at the Advanced Light Source (ALS), a windowless ultrahigh vacuum beamline covering the 1-6 keV photon-energy range. Beamline 9.3.1 is designed to simultaneously achieve the goals of high energy resolution, high flux, and high brightness at the sample. The mechanical design of the monochromator has been simplified, and recent developments in technology have been included. Measured mechanical precision of the monochromator shows significant improvement over existing designs. In tests with x-rays at NSLS beamline …


A Type I Hybrid Arq System With Adaptive Code Rates, Robert H. Deng, Michael L. Lin Feb 1995

A Type I Hybrid Arq System With Adaptive Code Rates, Robert H. Deng, Michael L. Lin

Research Collection School Of Computing and Information Systems

Type I hybrid ARQ systems use an error-control code of fixed rate for error-correction in each transmitted packet. In such systems, the code rate must be carefully chosen to match the channel bit error rate (BER) in order to maximize system throughput. Whenever there is a mismatch between code rate and channel BER, the throughput suffers. In this paper, we proposed a type I hybrid ARQ system which automatically adjusts its code rates to match channel BERs. The proposed system is very simple to implement and yet performs significantly better than type I hybrid ARQ systems of fixed code rate


Caring For Your Tires, Von Jarrett Feb 1995

Caring For Your Tires, Von Jarrett

All Current Publications

No abstract provided.


Diesel Engines, Von Jarrett Feb 1995

Diesel Engines, Von Jarrett

All Current Publications

No abstract provided.


Drain That Antifreeze, Von Jarrett Feb 1995

Drain That Antifreeze, Von Jarrett

All Current Publications

No abstract provided.


Oil Consideration To Lengthen Engine Life, Von Jarrett Feb 1995

Oil Consideration To Lengthen Engine Life, Von Jarrett

All Current Publications

No abstract provided.


Closed Orbit Bifurcations In Continuum Stark Spectra, Michael Courtney, Hong Jiao, Neal Spellmeyer, Daniel Kleppner, J. Gao, John B. Delos Feb 1995

Closed Orbit Bifurcations In Continuum Stark Spectra, Michael Courtney, Hong Jiao, Neal Spellmeyer, Daniel Kleppner, J. Gao, John B. Delos

Arts & Sciences Articles

We report an experimental and theoretical study of the effect of bifurcations of closed classical orbits in continuum Stark spectra. Our findings provide a natural way to understand how the spectrum evolves from a simple sinusoidal modulation at positive energy to a quasidiscrete spectrum below the classical ionization limit. The experiment employs scaled-energy spectroscopy of lithium. The results provide the first experimental confirmation of a formulation of closed-orbit theory that provides a quantitative description of the behavior of the spectrum at a bifurcation.


Ecotourism: Tripping With Mother Nature, Jill Barnard, Virginia Institute Of Marine Science, Wetlands Program Feb 1995

Ecotourism: Tripping With Mother Nature, Jill Barnard, Virginia Institute Of Marine Science, Wetlands Program

Reports

No abstract provided.


Engine Service Tips, Jumper Cables Used, Von Jarrett Feb 1995

Engine Service Tips, Jumper Cables Used, Von Jarrett

All Current Publications

No abstract provided.


Tune-Up And Dynamometer Testing, Von Jarrett Feb 1995

Tune-Up And Dynamometer Testing, Von Jarrett

All Current Publications

No abstract provided.


Cold Tractor Operations, Von Jarrett Feb 1995

Cold Tractor Operations, Von Jarrett

All Current Publications

No abstract provided.


High-Brightness Beamline For X-Ray Spectroscopy At The Advanced Light Source, Rupert C. Perera, G. Jones, Dennis W. Lindle Feb 1995

High-Brightness Beamline For X-Ray Spectroscopy At The Advanced Light Source, Rupert C. Perera, G. Jones, Dennis W. Lindle

Chemistry and Biochemistry Faculty Research

Beamline 9.3.1 at the Advanced Light Source (ALS) is a windowless beamline, covering the 1-6 keV photon-energy range, designed to achieve the goals of high energy resolution, high flux, and high brightness at the sample. When completed later this year, it will be the first ALS monochromatic hard-x-ray beamline, and its brightness will be an order-of-magnitude higher than presently available in this energy range. In addition, it will provide flux and resolution comparable to any other beamline now in operation. To achieve these goals, two technical improvements, relative to existing x-ray beamlines, were incorporated. First, a somewhat novel optical design …


Semiclassical Treatment Of A Half-Cycle Pulse Acting On A One-Dimensional Rydberg Atom, C. D. Schwieters, John B. Delos Feb 1995

Semiclassical Treatment Of A Half-Cycle Pulse Acting On A One-Dimensional Rydberg Atom, C. D. Schwieters, John B. Delos

Arts & Sciences Articles

The final-state distribution of hydrogen, acted upon by a 1/2-cycle pulse, has been calculated semiclassically for a proposed one-dimensional experiment. This work was motivated by the recent experimental realization of half-cycle pulses by Jones, You, and Bucksbaum [Phys. Rev. Lett. 70, 1236 (1993)] in which preliminary studies of ionization and state redistribution for hydrogenlike atoms were carried out. To simplify the situation theoretically, an experiment is proposed in which an additional weak static electric field is imposed and approximately one-dimensional states are selected. Within this one-dimensional approximation the transition probability to various n states (n is the principal …


Half-Cycle Pulse Acting On A One-Dimensional Rydberg Atom: Semiclassical Transition Amplitudes In Action And Angle Variables, C. D. Schwieters, John B. Delos Feb 1995

Half-Cycle Pulse Acting On A One-Dimensional Rydberg Atom: Semiclassical Transition Amplitudes In Action And Angle Variables, C. D. Schwieters, John B. Delos

Arts & Sciences Articles

In this paper we derive the expression for the transition coefficient used in the preceding paper [C. D. Schwieters and J. B. Delos, Phys. Rev. A 51, 1023 (1995)] for principal-quantum-number transitions in one-dimensional hydrogen caused by half-cycle pulses. We briefly review the methods of Miller [Adv. Chem. Phys. 25, 69 (1974)] and Marcus [Chem. Phys. Lett. 7, 525 (1970); J. Chem. Phys. 54, 3965 (1971)], and then derive the result using the methods of Maslov and Fedoriuk [Semi-Classical Approximation in Quantum Mechanics, (Reidel, Dordrecht, 1981)]. Also, we examine the approximate reduction of hydrogen …


Bleeding Air From Diesel Fuel Lines & Filters, Von Jarrett Feb 1995

Bleeding Air From Diesel Fuel Lines & Filters, Von Jarrett

All Current Publications

No abstract provided.


Fuel System Maintenance, Von Jarrett Feb 1995

Fuel System Maintenance, Von Jarrett

All Current Publications

No abstract provided.


Is There Slime In Your Fuel, Von Jarrett Feb 1995

Is There Slime In Your Fuel, Von Jarrett

All Current Publications

No abstract provided.


Preventive Maintenance Checklist, Von Jarrett Feb 1995

Preventive Maintenance Checklist, Von Jarrett

All Current Publications

No abstract provided.


What You Need To Know About Retreads, Von Jarrett Feb 1995

What You Need To Know About Retreads, Von Jarrett

All Current Publications

No abstract provided.


Machinery Storage, Von Jarrett Feb 1995

Machinery Storage, Von Jarrett

All Current Publications

No abstract provided.


Section I: Thermodynamic Properties Of Hydrocarbon Radicals, Peroxy Hydrocarbon And Peroxy Chlorohydrocarbon Molecules And Radicals Section Ii: Kinetics And Reaction Mechanisms For : (1) Chloroform Pyrolysis And Oxidation (2) Benzene And Toluene Oxidation Under Atmospheric Conditions, Tsan-Horng Lay Jan 1995

Section I: Thermodynamic Properties Of Hydrocarbon Radicals, Peroxy Hydrocarbon And Peroxy Chlorohydrocarbon Molecules And Radicals Section Ii: Kinetics And Reaction Mechanisms For : (1) Chloroform Pyrolysis And Oxidation (2) Benzene And Toluene Oxidation Under Atmospheric Conditions, Tsan-Horng Lay

Dissertations

Alkyl radicals are important active intermediates in gas phase photochemistry and combustion reaction systems. With the exception of a limited number of the most elementary radicals, accurate thermodynamic properties of alkyl radicals are either not available or only rough estimations exist. An H atom Bond Increment approach is developed and a data base [sic] is derived, for accurately estimating thermodynamic properties (ΔHf°298, S°298 and Cp(T)) for generic classes of hydrocarbon radical species.

Reactions of alkyl radicals with molecular oxygen are one of the major reaction paths for these radicals in atmospheric photochemistry, oxidation of hydrocarbon …


Off-Line Hand-Printed Chinese Character Recognition Based On Stroke Matching, Sunshine Chang Jan 1995

Off-Line Hand-Printed Chinese Character Recognition Based On Stroke Matching, Sunshine Chang

Theses

The specific purpose of this thesis is the automated recognition of the off-line Chinese hand-printed characters by using a blue ball-point pen. Through mask processing, the main components in a Chinese character such as vertical, horizontal, and slant strokes can be extracted. Then, the connected components with the coordinates of the top, bottom, leftmost, and rightmost ends of each stroke extracted are found. From these coordinates, the length and position of each stroke can be computed.

According to the number, relative length, and relative position of each stroke, both of the coarse and fine rule-based classification can be made, and …


Removal Of Chlorinated Hydrocarbons From Water By Air Stripping And Solvent Sublation, Alpana Gami Jan 1995

Removal Of Chlorinated Hydrocarbons From Water By Air Stripping And Solvent Sublation, Alpana Gami

Theses

Removal of trichloroethylene, monochlorobenzene and 1,3 dichlorobenzene from water by air stripping and solvent sublation into an organic phase was investigated. The sublation solvents used were paraffin oil and decyl alcohol. The rate of removal from water by solvent sublation and air stripping was highest for trichloroethylene, followed by chlorobenzene and finally 1,3 dichlorobenzene. For the three compounds, solvent sublation had the greatest advantage over air stripping in the reduction of emission of the compounds to the atmosphere. For the three compounds, the removal was enhanced at higher flowrate in both air stripping and solvent sublation. For the removal of …


Ultra-Thin Silicon Wafer Bonding, Diyu Yan Jan 1995

Ultra-Thin Silicon Wafer Bonding, Diyu Yan

Theses

In this thesis the history and recent developments on the silicon direct bonding technique are reviewed. The growing applications of this technique in SOI, SOS and MEMS areas, difficulties and disadvantages of various bonding processes are discussed. A direct bonding procedure for attaching ultra-thin wafers less than 200 μm thick to substrate wafers is developed and described in detail. Difficulties in handling, aligning and annealing ultra-thin wafers are reported. Wafers of different doping concentration, thickness, surface roughness and chemical characteristics are tested for bondability. Methods to minimize voids and other failure mechanisms are proposed. A photodetector is designed based on …


Silicon Optical Fiber Pressure Sensor, Jian Pan Jan 1995

Silicon Optical Fiber Pressure Sensor, Jian Pan

Theses

A novel optical fiber pressure sensor based on a micromachined thin silicon diaphragm is proposed. Detail descriptions of the sensor structure, modulation principle and fabrication process are given.

The device operates on the following principle: Pressure deflects a silicon diaphragm which moves the output end of a light source fiber. The emitted light intensity is picked up and shared by two receiving fibers placed side by side. The variation of the intensity ratio in the receiving fibers caused by the relative motion of the emitting fiber can be easily converted to a linear signal versus the deflection of the silicon …


Requirements, Design And Business Process Reengineering As Vital Parts Of Any System Development Methodology, Alicja Ruszala Jan 1995

Requirements, Design And Business Process Reengineering As Vital Parts Of Any System Development Methodology, Alicja Ruszala

Theses

This thesis analyzes different aspects of system development life cycle, concentrating on the requirements and design stages. It describes various methodologies, methods and tools that have been developed over the years. It evaluates them and compares them against each other. Finally a conclusion is made that there is a very important stage missing in the system development life cycle, which is the Business Process Reengineering Stage.