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Selected Works

2002

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Articles 1 - 30 of 109

Full-Text Articles in Engineering

Przebieg Zmienności Stężeń Wybranych Zanieczyszczeń W Gazach Odlotowych Z Procesu Mokrego Gaszenia Koksu, Marian Mazur, Robert Oleniacz, Marek Bogacki Dec 2002

Przebieg Zmienności Stężeń Wybranych Zanieczyszczeń W Gazach Odlotowych Z Procesu Mokrego Gaszenia Koksu, Marian Mazur, Robert Oleniacz, Marek Bogacki

Robert Oleniacz

Continuous measurement results of selected constituent concentrations in the gases emitted to the air during the coke wet quenching process were presented and discussed in the paper. The measurements were carried out for the standard wet quenching tower. The research covered such substances as carbon dioxide, carbon monoxide, hydrogen sulfide, nitrogen oxide, nitrogen dioxide and a total content of hydrocarbons and hydrogen (combustible gases). Changeability of the substance concentrations depending of the quenching process duration was analyzed. Among other things the beginning of these substances formation, appearance of the maximum and the range of observed concentrations were taken into consideration. …


On The Nature Of The Electrochemically Synthesized Hard Fe-0.96 Mass Pct C Alloy Film Dec 2002

On The Nature Of The Electrochemically Synthesized Hard Fe-0.96 Mass Pct C Alloy Film

A.S. Md Abdul Haseeb

A hard Fe-0.96 mass pet C alloy with a hardness value of 810 HV has been electrochemically synthesized from a ferrous sulfate bath containing a small amount of citric acid and L-ascorbic acid. The nature of the alloy has been investigated by a number of techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Mössbauer spectroscopy, differential scanning calorimetry (DSC), and magnetic measurements. The decomposition behavior of the alloy is also studied and compared with that of thermally prepared martensite. It has been found that the electrochemically deposited Fe-C alloy exists in …


Cell Population Modelling Of Yeast Glycolytic Oscillations, Michael A. Henson, Dirk Muller, Matthias Reuss Dec 2002

Cell Population Modelling Of Yeast Glycolytic Oscillations, Michael A. Henson, Dirk Muller, Matthias Reuss

Michael A Henson

We investigated a cell-population modelling technique in which the population is constructed from an ensemble of individual cell models. The average value or the number distribution of any intracellular property captured by the individual cell model can be calculated by simulation of a sufficient number of individual cells. The proposed method is applied to a simple model of yeast glycolytic oscillations where synchronization of the cell population is mediated by the action of an excreted metabolite. We show that smooth one-dimensional distributions can be obtained with ensembles comprising 1000 individual cells. Random variations in the state and}or structure of individual …


Osaka University: A Focus Of Polymer Science: 70th Anniversary Celebration, Otto Vogl, Koichi Hatada Dec 2002

Osaka University: A Focus Of Polymer Science: 70th Anniversary Celebration, Otto Vogl, Koichi Hatada

Otto Vogl

No abstract provided.


Personalities In Polymer Science: Cover Page, Title Page, Introduction, And List Of Articles, Otto Vogl Dec 2002

Personalities In Polymer Science: Cover Page, Title Page, Introduction, And List Of Articles, Otto Vogl

Otto Vogl

A compilation of articles with short biographies of the scientists who played leading roles in the field and provided the basis of Polymer Science and Technology throughout the 20th century.


Self-Consistent Three Dimensional Models For Quantum Ballistic Transport In Open Systems, Eric Polizzi, N. Ben Abdallah Dec 2002

Self-Consistent Three Dimensional Models For Quantum Ballistic Transport In Open Systems, Eric Polizzi, N. Ben Abdallah

Eric Polizzi

A quasi-three-dimensional model for quantum ballistic transport in nanostructures is proposed. The model goes beyond the Thomas-Fermi approximation and is numerically more tractable than the full three-dimensional Schrödinger-Poisson model. Its derivation relies on the strong confinement of electrons at the heterojunction which allows us to split the three-dimensional Schrödinger equation into a one-dimensional Schrödinger equation for the confined direction and a two-dimensional Schrödinger equation in the transport direction. The space charge effects are taken into account in a three-dimensional framework. Numerical simulations of quantum waveguide devices such as T stubs and directional couplers are used to illustrate the accuracy of …


Applications Of Underground Structures For The Protection Of Critical Infrastructure, George H. Baker, Richard G. Little, Don A. Linger Nov 2002

Applications Of Underground Structures For The Protection Of Critical Infrastructure, George H. Baker, Richard G. Little, Don A. Linger

George H Baker

The U.S. President’s Commission on Critical Infrastructure Protection (PCCIP), convened in the wake of the bombing of the Murrah Federal Building in Oklahoma City, concluded that the nation’s physical security and economic security depend on our critical energy, communications, and computer infrastructures. While a primary motivating event for the establishment of the commission was the catastrophic physical attack of the Murrah Building, it is ironic that the commission focused its attention primarily on cyber threats. Their rationale was that cyber vulnerabilities posed a new, unaddressed challenge to infrastructure security. This approach was further questioned by the events of September 11, …


Supervisory Control And Data Acquisition (Scada) Systems, George H. Baker, Allan Berg Nov 2002

Supervisory Control And Data Acquisition (Scada) Systems, George H. Baker, Allan Berg

George H Baker

Our critical national infrastructure systems have become almost universally dependent upon computer-based control systems technically referred to as supervisory control and data acquisition (SCADA) systems. SCADA systems evolved from the telemetry and event-alarm systems developed in the early days of utilities. With the widespread use of SCADA systems, computers have become the "basis element" for much of our critical infrastructure. Thus, the disruption of controlling computer terminals and networks due to natural disasters, electric power failure, accidents or malicious activity can have catastrophic consequences.


On The Nature Of The Electrochemically Synthesized Hard Fe-0.96 Mass Pct C Alloy Film Nov 2002

On The Nature Of The Electrochemically Synthesized Hard Fe-0.96 Mass Pct C Alloy Film

A.S. Md Abdul Haseeb

A hard Fe-0.96 mass pet C alloy with a hardness value of 810 HV has been electrochemically synthesized from a ferrous sulfate bath containing a small amount of citric acid and L-ascorbic acid. The nature of the alloy has been investigated by a number of techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Mössbauer spectroscopy, differential scanning calorimetry (DSC), and magnetic measurements. The decomposition behavior of the alloy is also studied and compared with that of thermally prepared martensite. It has been found that the electrochemically deposited Fe-C alloy exists in …


The Use Of 4-Substituted Pyridines To Afford Amphiphilic, Pegylated Cadmium Selenide Nanoparticles, Habib Skaff, Todd S. Emrick Nov 2002

The Use Of 4-Substituted Pyridines To Afford Amphiphilic, Pegylated Cadmium Selenide Nanoparticles, Habib Skaff, Todd S. Emrick

Todd S. Emrick

Amphiphilic cadmium selenide (CdSe) nanoparticles were prepared by surface functionalization with novel ligands 1 and 2, composed of pyridine moieties substituted in the 4-position with polyethylene glycol (PEG) chains.


1. Yukio Imanishi, Otto Vogl Nov 2002

1. Yukio Imanishi, Otto Vogl

Otto Vogl

No abstract provided.


Assessment Of Concentrated Flow Through Riparian Buffers, Michael G. Dosskey, Matthew J. Helmers, Dean E. Eisenhauer, Thomas G. Franti, Kyle D. Hoagland Nov 2002

Assessment Of Concentrated Flow Through Riparian Buffers, Michael G. Dosskey, Matthew J. Helmers, Dean E. Eisenhauer, Thomas G. Franti, Kyle D. Hoagland

Matthew J. Helmers

Concentrated flow of surface runoff from agricultural fields may limit the capability of riparian buffers to remove pollutants. This study was conducted on four farms in southeastern Nebraska to develop a method for assessing the extent of concentrated flow in riparian buffers and for evaluating the impact that it has on sediment-trapping efficiency. Field methods consisted of mapping field runoff areas and their pathways to and through riparian buffers to streams. Mathematical relationships were developed from a model (VFSMOD) that estimates sediment-trapping efficiency from the ratio of buffer area to field runoff area. Among the farms surveyed, riparian buffers averaged …


Sustainability Issues In A Pollution Prevention Course, R. Counce, Samuel Morton, L. Perkin Oct 2002

Sustainability Issues In A Pollution Prevention Course, R. Counce, Samuel Morton, L. Perkin

Samuel A Morton

No abstract provided.


Prediction Of Solid Surface Cleaning In Aqueous Surfactant Solutions: A Thermodynamic Approach, Samuel Morton, D. Keffer, A. Davis, R. Counce, D. Depaoli, M. Hu Oct 2002

Prediction Of Solid Surface Cleaning In Aqueous Surfactant Solutions: A Thermodynamic Approach, Samuel Morton, D. Keffer, A. Davis, R. Counce, D. Depaoli, M. Hu

Samuel A Morton

No abstract provided.


Roentgen's First Public Lecture, Fathi Habashi Oct 2002

Roentgen's First Public Lecture, Fathi Habashi

Fathi Habashi

The Birmingham artist Robert Alan Thom (1915-1979) painted a picture in 1966 showing Wilhelm Conard Roentgen at his first public demonstration of the newly discovered X-rays in the evening of January 23, 1896. The lecture took place at the Physics Department Auditorium of the University of Würzburg in Germany where Roentgen was the rector. The painting shows Albert von Kölliker, professor of anatomy at the University putting his hand on a photographic plate to make an X-ray picture. The painting is published in an interesting book entitled Great Moments in Medicine by Parke, Davis & Company, Northwood Institute Press, Detroit …


Delivering On The 256 Qam Promise, Ron D. Katznelson Oct 2002

Delivering On The 256 Qam Promise, Ron D. Katznelson

Ron D. Katznelson

The accumulation of degradation factors in the downstream channels is reviewed with focus on headend/hub transmission-related noise aggregation due to a plurality of downstream Quadrature Amplitude Modulation (QAM) transmitters and upconverters. Substantial increase in the number of QAM transmitters based on frequency agile upconverters is expected. Unlike fixed channel upconverters, these do not have narrow band filters at their output, consequently imparting appreciable levels of broadband noise on the network when several such units are combined. Based on these factors and other noise contributions, it is shown that additional impairments due to fluctuations associated with composite distortion terms on the …


Likwidacja Strefy Ochronnej Huty Katowice I Zakładów Koksowniczych "Przyjaźń" W Dąbrowie Górniczej, Marian Mazur, Robert Oleniacz, Marek Bogacki Oct 2002

Likwidacja Strefy Ochronnej Huty Katowice I Zakładów Koksowniczych "Przyjaźń" W Dąbrowie Górniczej, Marian Mazur, Robert Oleniacz, Marek Bogacki

Robert Oleniacz

Legislation changes in Poland concerning the protective zones (created around industrial plants particularly harmful to the environment) were presented in the paper. Conditions connected with forming, developing and partial elimination of the protective zone existing around the "Katowice" steelworks and the coke plant Przyjaźń in Dąbrowa Górnicza (Poland) since 1978 were characterized as well.

English title: Elimination of the protective zone of the Katowice steelworks and the coke plant Przyjaźń in Dąbrowa Górnicza.


"Estimación De Variables De Estado De Órbita Satelital Con Filtro De Kalman Extendido", Fabricio I. Salgado, E. Amthauer Oct 2002

"Estimación De Variables De Estado De Órbita Satelital Con Filtro De Kalman Extendido", Fabricio I. Salgado, E. Amthauer

Fabricio I. Salgado MSc.

Abstract: this paper presents the formulation of Extended Kalman Filter, Continuous-Discreet case (C-D EKF) and his application to the determination of state of satelite orbit, verifies the performance of the algorithm when it exists a good model for the process and measurement. It is observed the influence of the passage of integration in the estimation and importance that gives to the algorithm to the predictions and measurements.


Systematic Microstructure Variability In Double-Diffusively Stable Coastal Waters Of Nonuniform Density Gradient, Timothy F. Duda, Chris R. Rehmann Oct 2002

Systematic Microstructure Variability In Double-Diffusively Stable Coastal Waters Of Nonuniform Density Gradient, Timothy F. Duda, Chris R. Rehmann

Chris R. Rehmann

Conductivity microstructure, water velocity, and stratification were measured during a tow-yo transect near the New England shelf/slope front in early August 1997. Velocity data were collected with an acoustic Doppler profiler on the ship. The other data were collected with a towed platform. Estimates of χ, the rate of dissipation of temperature variance, were computed from the conductivity data with vertical resolution of 0.3 m. Relationships between χ and shear, temperature gradient, buoyancy frequency (N), and gradient Richardson number (Ri) were explored, with special focus on measurements taken in waters stable to double-diffusive processes (to avoid ambiguity of interpretation) and …


2. Toshinobu Higashimura, Otto Vogl Oct 2002

2. Toshinobu Higashimura, Otto Vogl

Otto Vogl

No abstract provided.


High-Efficiency Polymer-Based Electrophosphorescent Devices, Xiong Gong Sep 2002

High-Efficiency Polymer-Based Electrophosphorescent Devices, Xiong Gong

Xiong Gong

High efficiency electrophosphorescence has been achieved by using [Ir(DPF)3]-doped polyvinylcarbazole/biphenyl-1,3,4-oxadiazole co-polymers (see Figure). Light-emitting devices with luminous efficiencies up to 36 cd/A can be realized with polymeric host/heavy metal complex guest systems, fabricated by processing the luminescent layer from solution.


Method Of Manufacturing A Semiconductor Wafer Level Package, Us Patent # 6,465,281, Daxue Xu, Henry H. Hughes, Paul L. Bergstorm, Frank A. Shemansky, Hak-Yam Tsoi Sep 2002

Method Of Manufacturing A Semiconductor Wafer Level Package, Us Patent # 6,465,281, Daxue Xu, Henry H. Hughes, Paul L. Bergstorm, Frank A. Shemansky, Hak-Yam Tsoi

Paul Bergstrom

A semiconductor wafer level package used to encapsulate a device fabricated on a semiconductor substrate wafer before dicing of the wafer into individual chips. A cap wafer may be bonded to the semiconductor substrate using a low temperature frit glass layer as a bonding agent. The frit glass layer is in direct contact with the device. A hermetic seal is formed by a combination of the semiconductor substrate wafer, the cap wafer and the frit glass layer. A second embodiment of the package does not contain a cap wafer.


Decentralized Adaptive Coordination And Control Of Uninhabited Autonomous Vehicles Via Surrogate Optimization, Raúl Ordóñez Sep 2002

Decentralized Adaptive Coordination And Control Of Uninhabited Autonomous Vehicles Via Surrogate Optimization, Raúl Ordóñez

Raúl Ordóñez

No abstract provided.


Time Management—A Design-Build Builder's Perspective, Srinath Pai Kasturi, Douglas D. Gransberg Sep 2002

Time Management—A Design-Build Builder's Perspective, Srinath Pai Kasturi, Douglas D. Gransberg

Douglas D. Gransberg

Time management in design-build construction encompasses efficient project management controls, scheduling and execution of the contract as agreed upon by the parties. Time management is one of the prime areas of concern to the builder and his team. It plays an important role in shaping the progress of projects and thus is decisive in determining its course. This article explains the importance of time management in construction. Time management techniques on a (builder prime, architect subcontract) design build project from a builders perspective are presented. The builder ideally has to prioritize his tasks based on the resources and manpower of …


3. Otto Vogl, Gerald S. Kirshenbaum, Helga Roder Sep 2002

3. Otto Vogl, Gerald S. Kirshenbaum, Helga Roder

Otto Vogl

No abstract provided.


The Seabed Auv — A Platform For High Resolution Imaging, Hanumant Singh, Ryan Eustice, Christopher Roman, Oscar Pizarro Aug 2002

The Seabed Auv — A Platform For High Resolution Imaging, Hanumant Singh, Ryan Eustice, Christopher Roman, Oscar Pizarro

Christopher N. Roman

No abstract provided.


Analytical Model For The Optical Functions Of Amorphous Semiconductors From The Near-Infrared To Ultraviolet: Applications In Thin Film Photovoltaics, A. S. Ferlauto, G. M. Ferreira, Joshua M. Pearce, C. R. Wronski, R. W. Collins, Xunming Deng, Gautam Ganguly Aug 2002

Analytical Model For The Optical Functions Of Amorphous Semiconductors From The Near-Infrared To Ultraviolet: Applications In Thin Film Photovoltaics, A. S. Ferlauto, G. M. Ferreira, Joshua M. Pearce, C. R. Wronski, R. W. Collins, Xunming Deng, Gautam Ganguly

Joshua M. Pearce

We have developed a Kramers–Kronig consistent analytical expression to fit the measured optical functions of hydrogenated amorphous silicon(a-Si:H) based alloys, i.e., the real and imaginary parts of the dielectric function(ε1,ε2) (or the index of refractionn and absorption coefficient α) versus photon energy E for the alloys. The alloys of interest include amorphous silicon–germanium (a-Si1−xGex:H) and silicon–carbon (a-Si1−xCx:H), with band gaps ranging continuously from ∼1.30 to 1.95 eV. The analytical expression incorporates the minimum number of physically meaningful, E independent parameters required to fit (ε1,ε2) versus E. The fit is performed simultaneously throughout the following three regions: (i) the below-band gap …


Struggles Of The ‘Father’, Aimee Dechambeau Aug 2002

Struggles Of The ‘Father’, Aimee Dechambeau

Aimée L. deChambeau

Biographical account of Konstantin Eduardovich Tsiolkovsky, the father of Soviet cosmonautics.


Maximization Of The Open Circuit Voltage For Hydrogenated Amorphous Silicon N–I–P Solar Cells By Incorporation Of Protocrystalline Silicon P-Type Layers, R. J. Koval, Chi Chen, G. M. Ferreira, A. S. Ferlauto, Joshua M. Pearce, P. I. Rovira, C. R. Wronski, R. W. Collins Aug 2002

Maximization Of The Open Circuit Voltage For Hydrogenated Amorphous Silicon N–I–P Solar Cells By Incorporation Of Protocrystalline Silicon P-Type Layers, R. J. Koval, Chi Chen, G. M. Ferreira, A. S. Ferlauto, Joshua M. Pearce, P. I. Rovira, C. R. Wronski, R. W. Collins

Joshua M. Pearce

In studies of hydrogenated amorphous silicon(a-Si:H) n–i–psolar cells fabricated by rf plasma-enhanced chemical vapor deposition (PECVD), we have found that the maximum open circuit voltage (Voc) is obtained by incorporating p-type doped Si:H layers that are protocrystalline in nature. Specifically, these optimum p layers are prepared by PECVD in the a-Si:H growth regime using the maximum hydrogen-to-silane flow ratio possible without crossing the thickness-dependent transition into the mixed-phase (amorphous+microcrystalline) growth regime for the ∼200 Å p-layer thickness. The strong dependence of the p-layer phase and solar cell Voc on the underlying i-layer phase also confirms the protocrystalline nature of the …


A Comprehensive Mathematical And Numerical Modeling Of Deep-Bed Grain Drying, Istadi Istadi, Johnner P. Sitompul Aug 2002

A Comprehensive Mathematical And Numerical Modeling Of Deep-Bed Grain Drying, Istadi Istadi, Johnner P. Sitompul

Istadi

This paper deals with comprehensive mathematical and numerical modeling of deep-bed grain drying. In order to build the process model, it is necessary to analyze the transport in both grain and gas phases. Experimental works were carried out for a layer of grain bed in order to validate the models. The models consider momentum, energy, and mass conservation within grain and drying air phase. The twodimensional dynamic equations of energy and mass conservation are solved numerically by finite-difference method (FDM) and utilizing alternating direction implicit algorithm within grain and drying air phase, while momentum conservation are solved by finite difference …