Physical Sciences and Mathematics Commons^™

Knowledge Discovery And Modeling In Genomic Databases, Michael M. Yin

Dissertations

This dissertation research is targeted toward developing effective and accurate methods for identifying gene structures in the genomes of high eukaryotes, such as vertebrate organisms. Several effective hidden Markov models (HMMs) are developed to represent the consensus and degeneracy features of the functional sites including protein-translation start sites, mRNA splicing junction donor and acceptor sites in vertebrate genes. The HMM system based on the developed models is fully trained using an expectation maximization (EM) algorithm and the system performance is evaluated using a 10-way cross-validation method. Experimental results show that the proposed HMM system achieves high sensitivity and specificity in …

Radiation Transport Modeling Of Beam-Target Experiments For The Aaa Project: Quaterly Report, June 01- August 31, 2002, William Culbreth

Reactor Campaign (TRP)

The national development of technology to transmute nuclear waste depends upon the generation of high-energy neutrons produced by proton spallation. Proton accelerators, such as LANSCE at the Los Alamos National Laboratory, are capable of producing 800 MeV protons. By bombarding a lead /bismuth target, each proton may generate up to 25 neutrons that can activate fission of transuranic isotopes. Students at UNLV have been involved in radiation transport calculations in collaboration with researchers at the Los Alamos National Laboratory and at the Argonne National Laboratory.

Hydrogen-Induced Embrittlement Of Candidate Target Materials For Applications In Spallation-Neutron-Target Systems: Quarterly Progress Report (June 01 – August 31, 2002), Ajit K. Roy, Brendan O'Toole

Transmutation Sciences Materials (TRP)

The primary objective of this task is to evaluate the effect of hydrogen on environment-assisted cracking of candidate target materials for applications in spallation-neutron-target (SNT) systems such as accelerator production of tritium (APT) and accelerator transmutation of waste (ATW). The materials selected for evaluation and characterization are martensitic stainless steels including Alloy HT-9, Alloy EP 823 and Type 422 stainless steel. The susceptibility to stress corrosion cracking (SCC) and hydrogen embrittlement (HE) of these materials are being evaluated in environments of interest using tensile specimens under constant load and slow-strain-rate (SSR) conditions. Further, the localized corrosion behavior of these alloys …

Use Of Positron Annihilation Spectroscopy For Stress-Strain Measurements: Quarterly Progress Report (June 1 – August 31, 2002), Ajit K. Roy

Transmutation Sciences Materials (TRP)

The purpose of this collaborative research project involving the University of Nevada Las Vegas (UNLV), the Idaho State University (ISU), and the Los Alamos National Laboratory (LANL) is to evaluate the feasibility of determining residual stresses in cold-worked, plastically-deformed, and welded materials using a nondestructive method based on positron annihilation spectroscopy. This technique uses γ-rays from a small MeV electron Linac to generate positrons inside the sample via pair production. This method is known to have capabilities of characterizing defects in thick specimens, that could not be accomplished by conventional positron technique or other nondestructive methods. The generated data will …

Intramural, Collaborative Learning Systems, Robert S. Friedman

Theses

This thesis focuses on three related concepts: problem-based collaborative learning; the use of multimedia tools in learning systems; and participatory design as a software engineering methodology to create multimedia tools to be used in learning systems. A literature review of the three areas is followed by an overview of the pedagogical, technological, and business trends that affect the direction of innovation in education, including problem-based learning. A discussion of a software engineering project to develop a multimedia application that enhances the learning of geography skills and puts the programming, interface design and multimedia systems capabilities of college students into action …

Statistical Image Analysis Of Spotted Arrays, Filippo Posta

Theses

There is a lot of systematic and specific variability in microarray experiments, this variability affects measured gene expression levels, leading to unreliable gene profiling or an heavy load of extra experiment to statistically confirm the data observed in one experiment.

The aim of this work is to systematically analyze, using statistics, the image derived from a cDNA microarray experiment to have a better understanding of this variability and thus a better confidence over the data obtained from an experiment.

Using technologies available at the Center for Applied Genomics, Newark, New Jersey. Selected images derived from different type of microarray experiments …

An Algorithm For Estimating The Quality Of Microarrays, Ajeet S. Sodhi

Theses

Microarray technology is currently one of the most valuable gene expression tools in molecular biology allowing the experimenter to simultaneously quantify the expression of thousands of genes. It is also one of the most difficult tools to use accurately as each microarray produces a large amount of information that needs to be inspected and normalized before analysis. As the size of a microarray or number of replicates increase, the use of manual inspection becomes impractical. The aim of this thesis is to introduce an algorithm that evaluates each feature of a microarray from the scanned data file. A quality score …

Design And Evaluation Of Processes For Fuel Fabrication: Year 1 Final Report, Georg F. Mauer

Fuels Campaign (TRP)

The project objective is the design and evaluation of manufacturing processes for transmuter fuel fabrication. The large-scale deployment of remote fabrication and refabrication processes will be required for all transmutation scenarios. Current program emphasis is on a five-year effort to determine the feasibility of transmutation as a technology to limit the need for repository storage of spent commercial fuel. The evaluation of the fabrication processes will create a decision support data base to document design, operations, and costs. Fabrication processes required for different fuel types differ in terms of equipment types, throughput, and cost. The year 1 project was focused …

Effects Of Grand-Cycle Cessation On The Diagenesis Of Upper Cambrian Carbonate Deposits In The Southern Appalachians, U.S.A, Bosiljka Glumac, Kenneth R. Walker

Geosciences: Faculty Publications

The vertical transition from the mainly subtidal alternating shale and carbonate units (or grand cycles) of the Conasauga Group (Middle to Upper Cambrian) to the peritidal dolostone of the Knox Group (Upper Cambrian to Lower Ordovician) marks a major change in the early Paleozoic passive-margin sedimentation of the southern Appalachians. The grand cycles represent an interplay between intrashelf shale basin and carbonate-platform deposition. The end of grand-cycle deposition occurred in response to carbonate platform progradation over the infilled intrashelf basin and is associated with a prominent change in diagenetic patterns observed in the uppermost Conasauga Group strata-the Maynardville Formation. The …

Semiparametric Regression Analysis On Longitudinal Pattern Of Recurrent Gap Times, Ying Qing Chen, Mei-Cheng Wang, Yijian Huang

U.C. Berkeley Division of Biostatistics Working Paper Series

In longitudinal studies, individual subjects may experience recurrent events of the same type over a relatively long period of time. The longitudinal pattern of the gaps between the successive recurrent events is often of great research interest. In this article, the probability structure of the recurrent gap times is first explored in the presence of censoring. According to the discovered structure, we introduce the proportional reverse-time hazards models with unspecified baseline functions to accommodate heterogeneous individual underlying distributions, when the ongitudinal pattern parameter is of main interest. Inference procedures are proposed and studied by way of proper riskset construction. The …

Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics-Task V: Final Report -Phase I 09/01/2001-08/30/2002, Samir Moujaes, Yitung Chen

Transmutation Sciences Materials (TRP)

The Lead-Bismuth eutectic (LBE) has been determined from previous experimental studies by the Russians and the European scientific community to be a potential material that can be used as a spallation target and coolant for the AAA proposed application. Properly controlling the oxygen content in LBE can drastically reduce the LBE corrosion to structural steels. However, existing knowledge of material corrosion performance was obtained from point-wise testing with only very sparse experimental data. Scientists have noticed that the concentration of oxygen dissolved in the liquid alloy could control the corrosion rate of steels exposed to Pb or Pb-Bi. At high …

Analysis For Cooperative Behavior Effectiveness Of Autonomous Wide Area Search Munitions, Sang M. Park

Theses and Dissertations

The purpose of this study is to investigate how a simulation model can accurately represent the performance of the autonomous wide area search munitions, and to find the effectiveness of the cooperative behavior on the autonomous munitions. Though it does not provide a practical solution for the development of the autonomous wide area search munitions, this research will show some meaningful allocations of the munitions tasks that are applicable to the development of the autonomous munitions. For the first phase, this thesis presents how accurately a simplified simulation model can represent a proposed weapon system by comparing the simulation results …

Narendra Jaggi, Charlie Schlenker

Interviews for WGLT

Charlie Schlenker interviews Professor of Physics Narendra Jaggi about his work with computer modeling of ethnic living choices. (requires RealPlayer)

A False Planet Around Hd 192263, Gregory W. Henry, Robert A. Donahue, Sallie L. Baliunas

Information Systems and Engineering Management Research Publications

We present new high-precision Strömgren photometry and Ca II H and K spectrophotometry of HD 192263. Based on radial velocity variations detected previously by two groups, this K2 V star was thought to host a 0.75 MJup (minimum mass) planetary companion in a 24 day orbit. Our photometric observations reveal periodic variations that match the purported planetary orbital period, while the Ca II H and K emission fluxes are modulated on half the planetary period. This suggests that rotational modulation of the visibility of stellar surface activity is the source of the observed radial velocity variations. Therefore, HD 192263 should …

Optimum Of Catalyst Layers For Direct Methanol Fuel Cells, Jun Zhang, Lei Li, Li Xu, Yu-Xin Wang

Journal of Electrochemistry

The performances of membrane electrode assemblies (MEAs)with various Pt loading were compared. The amount of Nafion in a catalytic layer was optimized, and the effect of Nafion loading on the resistance of MEAs was investigated with ac impedance spectroscopy. For a MEA with both Pt 4 mg/cm² in the anode and the cathode, suitable Nafion loading was 21.4 wt% in the anode. With 21.4 wt% Nafion loading in the cathode, the Direct Methanol Fuel Cells(DMFC) showed the highest performance at high current density. While, the DMFC performances came down, as Nafion loading increasing,for ohm and concentration polarization.

Electrochemical Properties Of Nitrate Immobilized On Gold Electrodes With 2-Aminoethanethiol Sams, Ya-Ru Song, Hong Wu, Hui-Bo Shao

Journal of Electrochemistry

Nitrate reductase (NR) and phospholipids were immobilized on gold electrodes with 2-aminoethanethio(AET) SAMs. After Au/AET/NR and Au/AET/NR/lipid were soaked in pH 7 phosphate buffers for days, a pair of pre-reversible peak appeared at around 0.202 V and 0.149 V respsctively, irregularly grew with soaking time in blank buffer.The cathodic peak current (i_pcl) of Au/AET/NR system had linear relationship with scan rate between 0.02 and 0.5 V⋅s^-1 ,while i_pcl was proportional to V^1/2 in Au/AET/NR/lipid system. The direct electron transfer of enzyme electrodes was strongly affected by pH. Compared with Au/AET, NR exhibited a higher electrochemical …

Study On Modification Of Spinel Limn2O4 By Overcoating, Ren-Gang Zhang, Shi-Xi Zhao, Jung-Lei Xia, Han-Xing Liu

Journal of Electrochemistry

The surface of spinel LiMn₂O₄ was modified by the sol-gel process with LiCoO₂-coated LiMn₂O₄ and studied by XRD, SEM and EPMA. The results have shown that the surface of the coated grains heated at 700 ℃ for 10h, which is cubic spinel, were Co-rich. The amount of Co³⁺ in the grains changed owing to different place of the grain and decreased from surface to inner parts. Using the coated as the cathode of Li-ion cells, the initial capacity deceased slightly, but the amount of Mn²⁺ solving in electrolyte decreased, Jahn-Teller …

Facilitated K+ Ion Transfer By Db18c6 Across The Micro Liquid/Liquid Interface, Dong-Ping Zhan, Bing-Liang Wu

Journal of Electrochemistry

A novel microcavity Ag|AgCl electrode was fabricated to construct the micro-interface of two immiscible electrolyte solutions(ITIES). The transfer reactions of K⁺ ion facilitated by DB18C6 across the water/1,2-DCE interface was investigated with the three-electrodes system. The corresponding reaction parameters were derived from the voltammetric data. The results showed that the microcavity electrode would be a useful and efficient tool to investigate the charge transfer reactions at ITIES.

Diffusion Of Hydrogen At Iron Apply For Electrochemical Oscillating Permeation, Li Zhang, Ren-He Yin, Zhan-Mei Sun

Journal of Electrochemistry

The diffusion of hydrogen in iron was measured using electrochemical oscillating permeation. Through the samples in the different frequencies, it was found that diffusion of hydrogen at iron is of linear relation with boundary condition, which is the key to Fick's diffusion equation amplitude in the liquor. We can exploit this line relation getting the diffusion of hydrogen at iron.

Xrd Study On Highly Preferred Orientation Cu Electrodeposit, Min Gu, Fang-Zu Yang, Ling Huang, Shi-Bing Yao, Shao-Min Zhou

Journal of Electrochemistry

Copper electrodeposit was obtained in CuSO₄+H₂SO₄ electrolyte solution by electrodeposition and its structure was studied by XRD. The results showed that copper electoddeposits with the highly preferred orientations of (220) and (111) could be obtained at current density 4.0 A/dm² and 15.0 A/dm², respectively. The texture coefficient (TC) values were increased by thickness of Cu deposits. The thickness would be, to obtain Cu electrodeposit with (111) highly preferred orientation, about 7 times of that of (220) highly preferred orientation, which indicated that(220) face was easier to be remained than (111) face and …

Ionic Conduction In Ba0.95Ce0.9Y0.1O3 - Α Solid Oxide And Its Performance In Fuel Cell, Gui-Lin Ma, Ding-Xian Jia, Li-Gan Qiu, Hui Shi, Rong Chen

Journal of Electrochemistry

Using Ba_0.95Ce_0.9Y_0.1O_3-α as a solid electrolyte and porous platinum as electrodes,hydrogen and oxygen concentration cells and hydrogen-air fuel cell were constructed, respectively. Electromotive forces (MEFs) of the gas concentration cells and I-V characteristics of the fuel cell were detdrmined in the temperature range of 600～1 000 ℃. The Ba_0.95Ce_0.9Y_0.1O_3-α exhibited almost the pure protonic conduction under hydrogen gas,and a mixed conduction of oxide-ion and electron hole with oxide-ion transport number of 0.3～0.5 under oxygen gas. It exhibited a mixed conduction of proton and oxide-ion with the …

Modification Of Molybdenum Nitride Electrode For Supercapacitor(I)——The Effect Of Ammonium Vanadate On The Properties Of Molybdenum Nitride Electrode, Xue-Liang Li, Dao-Rong Luo, Hua-Lin Wang, Jian-Bo He, Yun-Guei Zhu

Journal of Electrochemistry

The effect of vanadium on the properties of the electrode of molybdenum nitride has been studied by using XRD, SEM and cyclic voltammetry. Modified molybdenum nitride was made as follow: films were coated by dipping titanium sheet in the solution containing different composition of molybdenum oxide, ammonium vanadate, ammonia, glycol and oxalic acid, and coated films are reacted with free ammonia. The results show that the specific capacitance of modified electrode was considerably increased and the operation voltage was broadened with the addition of ammonium vanadate in the dipping solution. The mechanism of these effects generated is the formation of …

Pure Hap Film Prepared By Direct Electrodepositing On Metallic Surface And Its Mechanism, Hao-Bing Hu, Chang-Jian Lin, Fei Chen, Ren Hu, Ming Guo

Journal of Electrochemistry

In controlling concentration of Ca²⁺ and PO₄^3- in electrodeposition solution, the HAP film on Ti alloy has been deposited directly. Using XRD and SEM we have learned that prepared HAP is intact in crystal and equal in dimension. Thermodynamic calculation indicated that the HAP is easer formation of than that TCP of. With the XRD, SEM analyses and thermodynamic calculation, the electrodeposition mechanism has been discussed. It was proved that electrodepositon is a two-stage process and formation of HAP is a direct process from solution ions to HAP crystal without precursor.

Study On Hydrogen Evolution Performance Of Nickel-Tin Electrode, Tian-Yi Chang, Bao-Hong Zhang, Wenbo Cong, Yao Luo

Journal of Electrochemistry

The cathode active material with low hydrogen evolution overvoltage was prepared by electroplating Ni-Sn alloy on the ferrous basic body.This kind of material can be applied in the diaphragm type of electrolytic tank to decrease cell voltage and save energy. On the condition according with cathode solution in the electrolytic tank (NaOH 120 g/L, NaCl 190 g/L, 90 ℃, i=150 mA/cm²), the overvoltage of hydrogen evolution was 88 mV. By the X-ray diffraction analysis, it was found that the structure of this kind of material was different from that of Ni-Sn alloy applied in traditional decoration. By using …

Some Consideration For Lithium-Ion Cells' Safety, Guang-Xia Hu, Jing-Ying Xie

Journal of Electrochemistry

The safety is the most important problem for lithium ion cells, especially for large lithium ion cells. In this paper, some information about lithium ion cells' safety can be learned by discussing several aspects of lithium ion cells, such as, materials of lithium ion cell, manufacturing processes, using conditions and so on.

Electrochemical Techniques For Measuring Anti-Corrosion Behavior Of The Thin Corrosion Inhibitor Layer To The 907a Steel, Yong-Tao Zhao, Jian-Hua Wu, Fan-Cai Chen, Zhong-Ping Gao, Jia Wang, Chang-Jiu Zhao

Journal of Electrochemistry

The corrosion inhibiting behavior of 907A steel, which was covered with thin inhibitor layers in moist seawater atmosphere,was studied. The electrochemical measurements, including EIS method and the coulostatic method, were used to atmospheric corrosioed monitor (ACM) under thin inhibitor layers to determine its corrosion rate. The results shown that the application of electrochemical methods such as the coulostatic technique and EIS could readily detect the on going process of film formation. Hence, the rapid evaluation of the thin inhibitor layers for 907A steel might be possible.

Thionine-Glutathione Self-Assembly Monolayer Modified Electrdoe And The Quasi-Reversible Response Of Dopamine, Cheng Fang, Zheng Luan, Wu-Ming Zhang, Xing-Yao Zhou

Journal of Electrochemistry

Thionine was bound onto a glutathione monolayer self-assembled on the surface of a gold electrode previously, the electrochemical characteristics of which were studied. It was found that dopamine had a quasi-reversible response and cathodic characterstics peak could be used to determine the concentration of dopamine in the range of 1.0～300 μmol·L^-1 in the presence of a higher concentration of ascorbic acid.

Synthesis And Characterization Of Lini0.8-XAlXCo0.2O2 As Cathodes For Lithium-Ion Batteries, Jun Zhang, Zhong-Kao Jin, Qing-He Yang, Qing-Mei Song, Xiao-Hua Ma, Xiang-Fu Zong

Journal of Electrochemistry

Single-phase solid solution of LiNi_0.8-xAl_xCo_0.2O₂ (0≤ x <0.1)had been synthesized and characterized by X-ray diffraction(XRD) and scanning electron microscopy (SEM). Their electrochemical performance was examined by charge-discharge cycling. The LiNi_0.71Al_0.09Co_0.2O₂ compound showed a discharge capacity of 152 mAh/g after 20 cycles that corresponds to 97.4% capacity retention. The beneficial effect of co-doping with Al and Co elements was corro-borated by slow scanning cyclic voltammograms(SSCV), electrochemical impedance spectrum (EIS) and differential scanning calorimetry (DSC) data on charged cathodes. These results show that the 2D-character of the crystal lattice was stabilized by co-doping with Al and Co, the phase transitions that occur during deintercalation or intercalation of Li-ions were significantly suppressed, …

Research Progress On Electrode Material In All-Vanadium Redox Battery, Hua Li, Shou-Wen Chang, Chuan-Wei Yan

Journal of Electrochemistry

An all-vanadium redox flow storage battery possesses many advantages over conventional storage batteries.The development statue of two types electrode materials (metal and compound type) is introduced in this article.

Initial Stages Of Copper Electrodeposition On Glassy Carbon Electrode, Ling Huang, Rui Zhang, Min Gu, Fang-Zu Yang, Shu-Kai Xu, Shao-Min Zhou

Journal of Electrochemistry

Initial stages of copper electrodeposition on glassy carbon electrode from acid sulphate solutions were studied using cyclic voltammetry and chronoamperometry. The electrolyte solution was a 0.05 mol.L^-1 copper sulphate, 1.4～1.8 mol⋅L^-1 sulphuric acid containing 1 mg·L^-1 2-mercaptobenzoimidazole, Results show that 2-mercaptobenzoimidazole produced an inhibition of the copper deposition, probably related to the adsorption,sulphuric acid promote copper electrodeposition. The initial deposition kinetics corresponded to a model including instantaneous nucleation and diffusion controlled growth.Addition of 2-mercaptobenzoimidazole and sulphuric acid did not change the initial nucleation of copper electrocrystallization, it increased the nucleation rate and the number density of nuclei …