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Engineering

Selected Works

2004

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Emisja Chlorowodoru Ze Spalania Węgla W Kotle Pyłowym, Marian Mazur, Robert Oleniacz, Przemysław Szczygłowski, Marek Bogacki Dec 2004

Emisja Chlorowodoru Ze Spalania Węgla W Kotle Pyłowym, Marian Mazur, Robert Oleniacz, Przemysław Szczygłowski, Marek Bogacki

Robert Oleniacz

Emission of hydrogen chloride (HCl) from coal combustion is not controlled just like for example sulpfur dioxide emission. But HCl emission is also important, because chlorine content in some types of coal can reach the similar level to sulfur content. In the paper the measurement results of HCl emission to the air during combustion of three types of coal with law content of chlorine were presented. The researches were carried out for a steam pulverized coal boiler (max. boiler efficiency – 430 t/h) during three various loads (respectively 65, 80 and 95 % of maximum efficiency) without flue gas desulfurization. …


Dislocation Structures And The Deformation Of Materials, Marisol Koslowski, Richard Alan Lesar, Robb Thomson Dec 2004

Dislocation Structures And The Deformation Of Materials, Marisol Koslowski, Richard Alan Lesar, Robb Thomson

Richard Alan Lesar

We present results from phase-field simulations of a two-dimensional model of dislocation microstructure development under increasing strain that incorporates the effects of the full, three-dimensional, microstructure in an approximate way. Despite its simplicity, the model yields quantitative predictions of both the deformation properties of face-centered cubic metals as well as key descriptors of the evolving microstructure over a wide range of stress and strain. The present results have important implications for how we interpret and describe the deformation properties of fcc materials.


Religious Sectarianism: Lessons To Be Learnt From Pakistan, Vikas Kumar Dec 2004

Religious Sectarianism: Lessons To Be Learnt From Pakistan, Vikas Kumar

Vikas Kumar

No abstract provided.


My Life With Polymer Science: Scientific And Personal Memoirs, Otto Vogl Dec 2004

My Life With Polymer Science: Scientific And Personal Memoirs, Otto Vogl

Otto Vogl

My "life story" will begin with my formative years, my childhood and student days at the University of Vienna, including my dissertation. It will be followed by my teaching appointment as an Instructor at the II. Chemical Institute of the University of Vienna. The urge to see other lands, learn other languages and scientific methods led to the Wandering Years that brought me to the United States. After three years spent as a Research Associate at the University of Michigan and at Princeton University I spent more than 13 years in an industrial career at the Du Pont Company in …


Charging-Induced Asymmetry In Molecular Conductors, Eric Polizzi, S. Datta, A. Ghosh, M. Paullson, F. Zahhid Dec 2004

Charging-Induced Asymmetry In Molecular Conductors, Eric Polizzi, S. Datta, A. Ghosh, M. Paullson, F. Zahhid

Eric Polizzi

We investigate the origin of asymmetry in various measured current-voltage (I-V) characteristics of molecules with no inherent spatial asymmetry, with particular focus on a recent break junction measurement. We argue that such asymmetry arises due to unequal coupling with the contacts and a consequent difference in charging effects, which can only be captured in a self-consistent model for molecular conduction. The direction of the asymmetry depends on the sign of the majority carriers in the molecule. For conduction through highest occupied molecular orbitals (i.e., HOMO or p-type conduction), the current is smaller for positive voltage on the stronger contact, while …


Biomimetic Actuators: Where Technology And Cell Biology Merge [Review Article], Michael Knoblauch, Winfried Peters Nov 2004

Biomimetic Actuators: Where Technology And Cell Biology Merge [Review Article], Michael Knoblauch, Winfried Peters

Winfried S. Peters

The structural and functional analysis of biological macromolecules has reached a level of resolution that allows mechanistic interpretations of molecular action, giving rise to the view of enzymes as molecular machines. This machine analogy is not merely metaphorical, as bio-analogous molecular machines actually are being used as motors in the fields of nanotechnology and robotics. As the borderline between molecular cell biology and technology blurs, developments in the engineering and material sciences become increasingly instructive sources of models and concepts for biologists. In this review, we provide a – necessarily selective – summary of recent progress in the usage of …


Physical And Chemical Characteristics Of Commercially Available Brake Shoe Lining Materials: A Comparative Study Nov 2004

Physical And Chemical Characteristics Of Commercially Available Brake Shoe Lining Materials: A Comparative Study

A.S. Md Abdul Haseeb

The physical and chemical characteristics of four commercial automotive brake shoe lining materials used in heavy vehicles have been investigated and compared. Relevant physical properties viz. density, water absorption and swelling characteristics were determined using standard test methods. X-ray diffraction, infrared spectroscopy and optical microscopic techniques were used to identify the constituents. It has been observed that all of the four friction materials contain phenol formaldehyde resin as the matrix. Other major ingredients were also the same in all the samples but their amount and size varied. These include asbestos as fibre reinforcement, barium sulphate as filler and brass particles …


Physical And Chemical Characteristics Of Commercially Available Brake Shoe Lining Materials: A Comparative Study Nov 2004

Physical And Chemical Characteristics Of Commercially Available Brake Shoe Lining Materials: A Comparative Study

A.S. Md Abdul Haseeb

The physical and chemical characteristics of four commercial automotive brake shoe lining materials used in heavy vehicles have been investigated and compared. Relevant physical properties viz. density, water absorption and swelling characteristics were determined using standard test methods. X-ray diffraction, infrared spectroscopy and optical microscopic techniques were used to identify the constituents. It has been observed that all of the four friction materials contain phenol formaldehyde resin as the matrix. Other major ingredients were also the same in all the samples but their amount and size varied. These include asbestos as fibre reinforcement, barium sulphate as filler and brass particles …


Microzonation Of Earthquake Hazard In Greater Delhi Area, R. N. Iyengar, Susanta Ghosh Nov 2004

Microzonation Of Earthquake Hazard In Greater Delhi Area, R. N. Iyengar, Susanta Ghosh

Susanta Ghosh

spate of earthquakes in the recent past, causing extensive damage, has heightened the sensitivity
of engineers and planners to the looming seismic risk in densely populated Indian cities. Delhi city
is in a seismically active region and hence it is important to understand the existing earthquake hazard
to the city on a scientific basis. This article, after discussing the seismo-tectonic status of the city and
its environs, presents probabilistic seismic hazard analysis of an area of 30 km x 40 km with its
centre at India Gate, Delhi city. The quantified hazard in terms of the rock level peak ground …


Metoda Oceny Trudności Oczyszczania I Toksyczności Spalin Powstających Podczas Spalania Odpadów, Robert Oleniacz Nov 2004

Metoda Oceny Trudności Oczyszczania I Toksyczności Spalin Powstających Podczas Spalania Odpadów, Robert Oleniacz

Robert Oleniacz

The paper presents a methodology for evaluating the cleaning difficulty and toxicity of combustion gases from waste incineration based on the knowledge of gases composition. This type of evaluation may be applicable to selection or modernization of flue gas cleaning systems for waste incineration plants and to comparative analy-sis of a pollution degree of raw (unclean) combustion gases. In the evaluation of the cleaning difficulty of gases six categories of difficulty have been identified for removal of selected substances or groups of substances. The evaluation is made individually for substances or groups of substances on condition their concentrations in flue …


Surface Structure Of Alkylsilylated Hzsm-5 As Phase-Boundary Catalyst, Hadi Nur, Yun Hau Ng, Mohd Nazlan Mohd Muhid, Halimaton Hamdan Nov 2004

Surface Structure Of Alkylsilylated Hzsm-5 As Phase-Boundary Catalyst, Hadi Nur, Yun Hau Ng, Mohd Nazlan Mohd Muhid, Halimaton Hamdan

Yun Hau Ng

The need for cleaner environment concerns motivates the development of more efficient catalytic system. Based on this consideration, recently a novel catalyst named "Phase-boundary catalyst", a bimodal amphiphilic solid catalyst, was proposed. It was demonstrated that the catalytic system containing phase-boundary catalyst required neither stirring to make an emulsion nor addition of a co-solvent to make a homogeneous solution to drive the reaction. The driving force that has prompted this paper is to investigate the surface structure of alkylsilylated HZSM-5 as phase-boundary catalyst. Temperature Programmed Desorption (TPD) of ammonia and, 13C and 29Si MAS NMR spectroscopy were used to elucidate …


Strain-Induced Disorder And Phase Transformation In Hexagonal Boron Nitride Under Quasi-Homogeneous Pressure: In Situ X-Ray Study In A Rotational Diamond Anvil Cell, Valery I. Levitas, J. Hashemi, Y. Z. Ma Nov 2004

Strain-Induced Disorder And Phase Transformation In Hexagonal Boron Nitride Under Quasi-Homogeneous Pressure: In Situ X-Ray Study In A Rotational Diamond Anvil Cell, Valery I. Levitas, J. Hashemi, Y. Z. Ma

Valery I. Levitas

One of the challenges in characterization of strain-induced transformations is to create uniform pressure. In this letter, conditions for nearly homogeneous pressure distribution are predicted and achieved experimentally. Compared to hydrostatic loading, plastic shear generally reduces the transformation pressure significantly. We observed, however, an unexpected phenomenon: the transformation of hexagonal to superhard wurtzitic BN under pressure and shear initiated at a pressure comparable to that in hydrostatic compression ($\sim 10$ \ensuremath{{\rm ~GPa}}). In situ X-ray diffraction revealed that plastic shear increases the disorder, while hydrostatic compression does not. This increase neutralizes the transition pressure reduction caused by shear. For the …


Pictures From My Life With Polymer Science: Album 01, Otto Vogl Nov 2004

Pictures From My Life With Polymer Science: Album 01, Otto Vogl

Otto Vogl

No abstract provided.


Development And Analysis Of A Software Package To Quantify In Vivo Polyethylene Wear After Total Hip Arthroplasty, Allison Kinney, Catherine Ambrose Oct 2004

Development And Analysis Of A Software Package To Quantify In Vivo Polyethylene Wear After Total Hip Arthroplasty, Allison Kinney, Catherine Ambrose

Allison Kinney

Since the first total hip arthroplasty (THA) in 1938, THA evolved and developed into one of the major concentrations of orthopaedic research. The typical hip implant device used today incorporates a femoral and an acetabular component that serve to replicate the anatomical and mechanical functions of the natural hip joint. However, several problems exist that can effect the function of the implant device. Wear in the polyethylene liner of the acetabular component of the total hip replacement device is known as one of the major factors that affects the longevity of total hip replacement devices. Both manual and computer-aided techniques …


Emisja Btx Towarzysząca Produkcji Wyrobów Węglowych I Grafitowych, Marian Mazur, Przemysław Szczygłowski, Robert Oleniacz, Marek Bogacki Oct 2004

Emisja Btx Towarzysząca Produkcji Wyrobów Węglowych I Grafitowych, Marian Mazur, Przemysław Szczygłowski, Robert Oleniacz, Marek Bogacki

Robert Oleniacz

The work presents results of direct measurements of benzene, toluene, ethyl benzene and xylenes (BTX or BTEX) emissions to the air from technological processes related with carbon and graphite manufacturing. The most important from all mentioned pollutants is benzene considered as one of the main factor of air pollution in the European Union. The highest concentrations of BTX were found in the fumes emitted from the tanks of liquid raw materials, while the highest levels of their emissions were from furnaces used for baking of green electrodes and other carbon products.

English title: BTX emission from production of graphite and …


Trapezoidal Phase-Shifting Method For 3d Shape Measurement, Peisen S. Huang, Song Zhang, Fu-Pen Chiang Oct 2004

Trapezoidal Phase-Shifting Method For 3d Shape Measurement, Peisen S. Huang, Song Zhang, Fu-Pen Chiang

Song Zhang

We propose a novel structured light method, namely trapezoidal phase-shifting method, for 3-D shape measurement. This method uses three patterns coded with phase-shifted, trapezoidal-shaped gray levels. The 3-D information of the object is extracted by direct calculation of an intensity ratio. Theoretical analysis showed that this new method was significantly less sensitive to the defocusing effect of the captured images when compared to the traditional intensity-ratio based methods. This important advantage makes large-depth 3-D shape measurement possible. If compared to the sinusoidal phase-shifting method, the resolution is similar, but the processing speed is at least 4.5 times faster. The feasibility …


Ordered Network Phases In Linear Poly(Isoprene-B-Styrene-B-Ethylene Oxide) Triblock Copolymers, Thomas H. Epps Iii, Eric W. Cochran, Travis S. Bailey, Ryan S. Waletzko, Cordell M. Hardy, Frank S. Bates Oct 2004

Ordered Network Phases In Linear Poly(Isoprene-B-Styrene-B-Ethylene Oxide) Triblock Copolymers, Thomas H. Epps Iii, Eric W. Cochran, Travis S. Bailey, Ryan S. Waletzko, Cordell M. Hardy, Frank S. Bates

Eric W. Cochran

The equilibrium phase behavior of 43 linear poly(isoprene-b-styrene-b- ethylene oxide) (ISO) triblock copolymer melts, with molecular weights that place these materials near the order-disorder transition, is reported. Ordered phase morphologies were characterized using small-angle X-ray scattering, transmission electron microscopy, dynamic mechanical spectroscopy, and static birefringence measurements. Interpretation of these results was aided by a modeling technique that facilitates resolution of reciprocal and real-space experimental data, leading to definitive three-dimensional morphological structures. Three distinct multiply continuous network morphologies are identified across a range of compositions between 0.1 ≤ f o ≤ 0.3, situated between two-domain and three-domain lamellae, where f o …


Pictures From My Life With Polymer Science: Album 02, Otto Vogl Oct 2004

Pictures From My Life With Polymer Science: Album 02, Otto Vogl

Otto Vogl

No abstract provided.


Knowledge Discovery From Multispectral Satellite Images, Arun D. Kulkarni Sep 2004

Knowledge Discovery From Multispectral Satellite Images, Arun D. Kulkarni

Arun Kulkarni

A new approach to extract knowledge from multispectral images is suggested. We describe a method to extract and optimize classification rules using fuzzy neural networks (FNNs). The FNNs consist of two stages. The first stage represents a fuzzifier block, and the second stage represents the inference engine. After training, classification rules are extracted by backtracking along the weighted paths through the FNN. The extracted rules are then optimized by use of a fuzzy associate memory bank. We use the algorithm to extract classification rules from a multispectral image obtained with a Landsat Thematic Mapper sensor. The scene represents the Mississippi …


Asymptotic Accuracy Of Geoacoustic Inversions, Michele Zanolin, Ian Ingram, Aaron Thode, Nicholas C. Makris Sep 2004

Asymptotic Accuracy Of Geoacoustic Inversions, Michele Zanolin, Ian Ingram, Aaron Thode, Nicholas C. Makris

Michele Zanolin

Criteria necessary to accurately estimate a set of unknown geoacoustic parameters from remote acoustic measurements are developed in order to aid the design of geoacoustic experiments. The approach is to have estimation error fall within a specified design threshold by adjusting controllable quantities such as experimental sample size or signal-to-noise ratio (SNR). This is done by computing conditions on sample size and SNR necessary for any estimate to have a variance that (1) asymptotically attains the Cramer–Rao lower bound (CRLB) and (2) has a CRLB that falls within the specified design error threshold. Applications to narrow band deterministic signals received …


Avalanches And Scaling In Plastic Deformation, Marisol Koslowski, Richard Alan Lesar, Robb Thomson Sep 2004

Avalanches And Scaling In Plastic Deformation, Marisol Koslowski, Richard Alan Lesar, Robb Thomson

Richard Alan Lesar

Plastic deformation of crystalline materials is a complex nonhomogeneous process characterized by avalanches in the motion of dislocations. We study the evolution of dislocation loops using an analytically solvable phase-field model of dislocations for ductile single crystals during monotonic loading. The distribution of dislocation loop sizes is given by P(A)∼A−σ, with σ=1.8±0.1. The exponent is in agreement with those found in acoustic emission experiments. This model also predicts a range of macroscopic behaviors in agreement with observation, including hardening with monotonic loading, and a maximum in the acoustic emission signal at the onset of yielding.


A Generalized Neuron Based Pss In A Multi-Machine Power System, D. K. Chaturvedi, O. P. Malik, P. K. Kalra Sep 2004

A Generalized Neuron Based Pss In A Multi-Machine Power System, D. K. Chaturvedi, O. P. Malik, P. K. Kalra

D. K. Chaturvedi Dr.

An artificial neural network can work as an intelligent controller for nonlinear dynamic systems through learning, as it can easily accommodate the nonlinearities and time dependencies. In dealing with complex problems, most common neural networks have some drawbacks of large training time, large number of neurons and hidden layers. These drawbacks can be overcome by a nonlinear controller based on a generalized neuron (GN) which retains the quick response of neural net. Results of studies with a GN-based power system stabilizer on a five-machine power system show that it can provide good damping over a wide operating range and significantly …


Microscale Simulation Of Martensitic Microstructure Evolution, Valery I. Levitas, Alexander V. Idesman, Dean L. Preston Sep 2004

Microscale Simulation Of Martensitic Microstructure Evolution, Valery I. Levitas, Alexander V. Idesman, Dean L. Preston

Valery I. Levitas

A new model for the evolution of multivariant martensitic microstructure in single crystals and polycrystals is developed. In contrast with Landau-Ginzburg models, which are limited in practice to nanoscale specimens, this new scale-free model is valid for length scales greater than 100 nm and without an upper bound. It is based on a thermodynamic potential in the volume fractions of the martensitic variants that exhibits an instability resulting in microstructure formation. Simulated microstructures in elastic single crystals and polycrystals under uniaxial loading are in qualitative agreement with those observed experimentally.


Pictures From My Life With Polymer Science: Album 03, Otto Vogl Sep 2004

Pictures From My Life With Polymer Science: Album 03, Otto Vogl

Otto Vogl

No abstract provided.


Biomolecule-Directed Assembly Of Nanoscale Building Blocks Studied Via Lattice Monte Carlo Simulation, Ting Chen, Monica H. Lamm, Sharon C. Glotzer Aug 2004

Biomolecule-Directed Assembly Of Nanoscale Building Blocks Studied Via Lattice Monte Carlo Simulation, Ting Chen, Monica H. Lamm, Sharon C. Glotzer

Monica H. Lamm

The self-assembly of functionalized inorganic nanoscale building blocks (NBB) was investigated using recognitive biomolecule linkers. The NBBs and linkers were studied using bond fluctuation model and algorithm on a simple cubic lattices. The loops contained in the soluble material to avoid double counting when calculating the fraction of loops. The algorithm was used to calculate additional network properties when volume fractions above the percolation threshold was simulated.


Screening Of Mgo- And Ceo2-Based Catalysts For Carbon Dioxide Oxidative Coupling Of Methane To C2+ Hydrocarbon, Istadi, Nor Aishah Saidina Amin Aug 2004

Screening Of Mgo- And Ceo2-Based Catalysts For Carbon Dioxide Oxidative Coupling Of Methane To C2+ Hydrocarbon, Istadi, Nor Aishah Saidina Amin

Istadi

The catalyst screening tests for carbon dioxide oxidative coupling of methane (CO2-OCM) have been investigated over ternary and binary metal oxide catalysts. The catalysts are prepared by doping MgO- and CeO2-based solids with oxides from alkali (Li2O), alkaline earth (CaO), and transition metal groups (WO3 or MnO). The presence of the peroxide (O2_2 ) active sites on the Li2O2, revealed by Raman spectroscopy, may be the key factor in the enhanced performance of some of the Li2O/MgO catalysts. The high reducibility of the CeO2 catalyst, an important factor in the CO2-OCM catalyst activity, may be enhanced by the presence of …


Network Phases In Abc Triblock Copolymers, Thomas H. Epps Iii, Eric W. Cochran, Cordell M. Hardy, Travis S. Bailey, Ryan S. Waletzko, Frank S. Bates Aug 2004

Network Phases In Abc Triblock Copolymers, Thomas H. Epps Iii, Eric W. Cochran, Cordell M. Hardy, Travis S. Bailey, Ryan S. Waletzko, Frank S. Bates

Eric W. Cochran

Many naturally occurring and engineered products are influenced by network structures. Collagen networks provide a scaffold for living tissue, while swollen arrays of physically cross-linked polypeptides constitute gelatin, the familiar dessert and electrophoresis medium. Although the associated mesh sizes differ by several orders of magnitude, these examples share a common feature: three-dimensional connectivity that imparts mechanical rigidity. Intercalating additional interconnected components can yield broader functions, e.g., ionic or electrical conductivity, optical band gaps, and tailored heat and mass transfer.


Shear-Induced Network-To-Network Transition In A Block Copolymer Melt, Eric W. Cochran, Frank S. Bates Aug 2004

Shear-Induced Network-To-Network Transition In A Block Copolymer Melt, Eric W. Cochran, Frank S. Bates

Eric W. Cochran

The tricontinuous (10, 3)c shear-induced network-to-network transition in a block copolymer melt was analyzed using small-angle x-ray scattering. Investigations show that field-induced network-to-network phase transition was unprecedented in soft condensed matter. It was found that shear transforms were used for self-assembling the soft material into a single crystal (10, 3)d network. The results show the delicate nature of block copolymers phase behavior, where candidate morphologies were spaced closely together on the free energy surface.


Contribution Of Support Means To Stresses Developed In Sheet Metal Coils, Jonathan A. Wickert, Y.M. Lee Aug 2004

Contribution Of Support Means To Stresses Developed In Sheet Metal Coils, Jonathan A. Wickert, Y.M. Lee

Jonathan A. Wickert

Sheet metal is often stored in large wound coils and processed through such manufacturing stages as cleaning, coating, and slitting in a finishing plant or thickness reduction in a rolling mill. During winding and unwinding operations, as well as during storage and transportation, a coil can be supported in a variety of methods. The coil can be formed on a relatively compliant fiber core, or it can be mounted with the core onto a drive shaft or a pair of core chucks. The stresses within the coil develop in response to the sheet metal's material properties, the process tension, and …


Pictures From My Life With Polymer Science: Album 04, Otto Vogl Aug 2004

Pictures From My Life With Polymer Science: Album 04, Otto Vogl

Otto Vogl

No abstract provided.