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Receive Sensitivity Characterization Of The Polysat Satellite Communication System, Ivan M. Bland 2010 California Polytechnic State University, San Luis Obispo

Receive Sensitivity Characterization Of The Polysat Satellite Communication System, Ivan M. Bland

Master's Theses

Following the successful launch of CP3 and CP4, the PolySat team noticed an unreliable uplink to both satellites. A significant problem with the PolySat COMM system is poor receive sensitivity of the communications system. Efforts have been made to improve the uplink margin, but without proper characterization of the receiver sensitivity, the problem cannot be fully addressed. By developing an accurate method of measuring receive sensitivity, a methodical approach can be used to properly diagnose the communication system and link budget. Two revisions of the PolySat COMM system will be measured and compared. An in-depth study of the PolySat COMM …


Classificiation Of Atrial Fibrillation Prone Patients Using Electrocardiographic Parameters In Neuro-Fuzzy Modeling,, Mirela Ovreiu, Marc Petre, Daniel J. Simon, Daniel Sessler, C Allen Bashour 2010 Cleveland Clinic Foundation

Classificiation Of Atrial Fibrillation Prone Patients Using Electrocardiographic Parameters In Neuro-Fuzzy Modeling,, Mirela Ovreiu, Marc Petre, Daniel J. Simon, Daniel Sessler, C Allen Bashour

Electrical and Computer Engineering Faculty Publications

Atrial Fibrillation (AF) is a significant clinical problem and the complications of cardiovascular postoperative AF often lead to longer hospital stays and higher heath care costs. The literature showed that AF may be preceded by changes in electrocardiogram (ECG) characteristics such as premature atrial activity, heart rate variability (HRV), and P-wave morphology. We hypothesize that the limitations of statistics-based attempts to predict AF occurrence may be overcome using a hybrid neuro-fuzzy prediction model that is better capable of uncovering complex, non-linear interactions between ECG parameters. We created a neuro-fuzzy network that was able to classify the patients into the control …


Shift Estimation Algorithm For Dynamic Sensors With Frame-To-Frame Variation In Their Spectral Response, Todd M. Giles, Majeed M. Hayat, Sanjay Krishna 2010 University of New Mexico - Albuquerque

Shift Estimation Algorithm For Dynamic Sensors With Frame-To-Frame Variation In Their Spectral Response, Todd M. Giles, Majeed M. Hayat, Sanjay Krishna

Electrical and Computer Engineering Faculty Research and Publications

This study is motivated by the emergence of a new class of tunable infrared spectral-imaging sensors that offer the ability to dynamically vary the sensor's intrinsic spectral response from frame to frame in an electronically controlled fashion. A manifestation of this is when a sequence of dissimilar spectral responses is periodically realized, whereby in every period of acquired imagery, each frame is associated with a distinct spectral band. Traditional scene-based global shift estimation algorithms are not applicable to such spectrally heterogeneous video sequences, as a pixel value may change from frame to frame as a result of both global motion …


Phase Unwrapping In The Presence Of Strong Turbulence, Casey J. Pellizzari 2010 Air Force Institute of Technology

Phase Unwrapping In The Presence Of Strong Turbulence, Casey J. Pellizzari

Theses and Dissertations

Phase unwrapping in the presence of branch points using a least-squares wave-front reconstructor requires the use of a Postprocessing Congruence Operation (PCO). Branch cuts in the unwrapped phase are altered by the addition of a constant parameter h to the rotational component when applying the PCO. Past research has shown that selecting a value of h which minimizes the proportion of irradiance in the pupil plane adjacent to branch cuts helps to maximize performance of adaptive-optics (AO) systems in strong turbulence. In continuation of this objective, this research focuses on optimizing the PCO while accounting for the cumulative effects of …


Novel And Simple High-Frequency Single-Port Vector Network Analyzer, Mohamed A. Abou-Khousa, Mark A. Baumgartner, Sergey Kharkovsky, R. Zoughi 2010 Missouri University of Science and Technology

Novel And Simple High-Frequency Single-Port Vector Network Analyzer, Mohamed A. Abou-Khousa, Mark A. Baumgartner, Sergey Kharkovsky, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Portable, accurate, and relatively inexpensive high-frequency vector network analyzers (VNAs) have great utility for a wide range of applications, encompassing microwave circuit characterization, reflectometry, imaging, material characterization, and nondestructive testing to name a few. To meet the rising demand for VNAs possessing the aforementioned attributes, we present a novel and simple VNA design based on a standing-wave probing device and an electronically controllable phase shifter. The phase shifter is inserted between a device under test (DUT) and a standing-wave probing device. The complex reflection coefficient of the DUT is then obtained from multiple standing-wave voltage measurements taken for several different …


Design Of Asynchronous Circuits For High Soft Error Tolerance In Deep Submicron Cmos Circuits, Weidong Kuang, Peiyi Zhao, J. S. Yuan, R. F. DeMara 2010 The University of Texas Rio Grande Valley

Design Of Asynchronous Circuits For High Soft Error Tolerance In Deep Submicron Cmos Circuits, Weidong Kuang, Peiyi Zhao, J. S. Yuan, R. F. Demara

Electrical and Computer Engineering Faculty Publications

As the devices are scaling down, the combinational logic will become susceptible to soft errors. The conventional soft error tolerant methods for soft errors on combinational logic do not provide enough high soft error tolerant capability with reasonably small performance penalty. This paper investigates the feasibility of designing quasi-delay insensitive (QDI) asynchronous circuits for high soft error tolerance. We analyze the behavior of null convention logic (NCL) circuits in the presence of particle strikes, and propose an asynchronous pipeline for soft-error correction and a novel technique to improve the robustness of threshold gates, which are basic components in NCL, against …


Effects Of Different Carbon Sources On Performance Of Li3V2(Po4)3/C Composite Cathode Materials, Kai-yuan LIU, Jian-shu HUANG, Li YANG 2010 School of Chemistry and Chemical Engineering,Shanghai JiaoTong University,Shanghai 200240,China;

Effects Of Different Carbon Sources On Performance Of Li3V2(Po4)3/C Composite Cathode Materials, Kai-Yuan Liu, Jian-Shu Huang, Li Yang

Journal of Electrochemistry

The monoclinic Li3V2(PO4)3 cathode materials were prepared by carbothermal reduction method,with methyl cellulose, chitosan(crab shells) or glucose anhydrous as carbon sources, respectively.The crystal structures, morphologies and the electrochemical performances were characterized by XRD, SEM and electrochemical measurement. The XRD patterns show that the samples obtained at 800 ℃ for 6 h have a pure monoclinic structure,which indicates that the carbon exists in amorphous phase. Electrochemical measurements show that the difference of carbon sources has a significant influence on the electrochemical properties of the materials. The Li3V2(PO4)3 …


Preparation And Characterization Of Sulfur/Mesoprous Carbon Composite Cathodes, Wen-hua ZHANG, Yao CHEN, Xin-ping AI, Yu-liang CAO 2010 College of Chemistry and Molecular Sciences,Wuhan University,Wuhan,430072,China;

Preparation And Characterization Of Sulfur/Mesoprous Carbon Composite Cathodes, Wen-Hua Zhang, Yao Chen, Xin-Ping Ai, Yu-Liang Cao

Journal of Electrochemistry

A sulfur/mesoporous carbon composite was prepared by thermally treating a mixture of sublimed sulfur and mesoporous carbon. The microstructure of the mesoporous carbon was characterized by BET analysis and X-ray diffraction(XRD). The electrochemical performance of the S/C composite as cathode materials was evaluated by the galvanostatic method. The results confirmed that the mesoporous carbon could not only greatly enhance the electrochemical activity of sulfur electrode, but also effectively confine the diffusion of dissolved polysulfides in organic electrolyte. As a result,the S/C composites showed high capacity, good cycle performance and excellent rate capability. The specific capacity of the S/C composite was …


The Synthesise Of Electron-Conducting Redox Hydrogel And Its Application In Microbial Fuel Cell, Kai-peng WANG, Sheng-li CHEN 2010 College of Chemistry and Molecular Sciences,Wuhan University,Wuhan 730042,Hubei,China;

The Synthesise Of Electron-Conducting Redox Hydrogel And Its Application In Microbial Fuel Cell, Kai-Peng Wang, Sheng-Li Chen

Journal of Electrochemistry

Efficient electron transfer between the microbe and the anode is key for the electricity generation in Microbial fuel cell(MFC).Through the modification of anode,the rate of electron transfer can be accelerated,therefore the performance of MFC can be enhanced.In this paper,we report the synthesis of a type of electronconducting and bio-compatible redox hydrogel and its application.The hydrogel consists of poly(4-vinylpyridine) as backbone and neutral red as the redox center.By immobiliazing neutral red on the backbone through covalent bond,the secondary contamination due to the soluble redox mediator to external environment can be prevented.MFCs using the hydrogel-modified carbon anode significantly exhibit shorter acclimation period,and …


Investigation Of Ceo2 As Cathode Electrocatalyst For Direct Borohydride Fuel Cell, Xue-min NI, Ya-dong WANG, Mu PAN 2010 State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan 430070,China;

Investigation Of Ceo2 As Cathode Electrocatalyst For Direct Borohydride Fuel Cell, Xue-Min Ni, Ya-Dong Wang, Mu Pan

Journal of Electrochemistry

The performance of CeO2 as oxygen reduction electrocatalyst in direct borohydride fuel cell was investigated.The experimental results indicate that CeO2 shows significant electrocatalytic performance for oxygen reduction and exhibits no observed promotion effect on hydrolysis or electro-oxidation of BH4-.The power density of experimental one-compartment fuel cell with CeO2 as cathode electrocatalyst can reach a 67.8 mW·cm-2 at room temperature.


Preparation And Electrochemical Behavior Of Li4Ti5O12 Nanosheets As Anode Material For Lithium Ion Battery, Yi-fei WANG, Yu-feng TANG, Zheng QIU, Li YANG 2010 School of Chemistry and Chemical Technology,Shanghai Jiao Tong University,Shanghai 200240,China;

Preparation And Electrochemical Behavior Of Li4Ti5O12 Nanosheets As Anode Material For Lithium Ion Battery, Yi-Fei Wang, Yu-Feng Tang, Zheng Qiu, Li Yang

Journal of Electrochemistry

Spinel lithium titanate(Li4Ti5O12) nanosheets with a size range of 200 ~400 nm were synthesized by hydrothermal process from the amorphous hydrous titanium oxide precursors.The as-prepared products were characterized by X-ray powder diffraction(XRD),scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The electrochemical behaviors of Li4Ti5O12 electrode in conventional organic electrolyte and ionic liquid electrolyte were investigated by using cyclic voltammetry,galvanostatic charge-discharge and AC impedance techniques.The experimental results indicate that the as-prepared nanostructured Li4Ti5O12,evaluated as anode material,exhibited good reversibility and cycle performance.It is expected to be a …


Synthesis Of High-Performance Lini1/3Co1/3Mn1/3O2 Cathode Materials Via Azeotropic Distillation Method, Sheng-an XIA, Li-xia YUAN, Ze YANG, Zhao-hui WANG, Yun-hui HUANG, Shuang LI, Wu-xing ZHANG, Ya-bin MENG, Wei-gong ZHENG 2010 School of Materials Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China;

Synthesis Of High-Performance Lini1/3Co1/3Mn1/3O2 Cathode Materials Via Azeotropic Distillation Method, Sheng-An Xia, Li-Xia Yuan, Ze Yang, Zhao-Hui Wang, Yun-Hui Huang, Shuang Li, Wu-Xing Zhang, Ya-Bin Meng, Wei-Gong Zheng

Journal of Electrochemistry

Layered LiNi1/3Co1/3Mn1/3O2 is one of the most promising alternative materials for LiCoO2 in lithium ion batteries due to its low cost,large capacity and excellent cyclability.In this paper,LiNi1/3Co1/3Mn1/3O2 was synthesized via azeotropic distillation method with isobutyl alcohol as an azeotropic agent.The structure and surface morphology were characterized by X-ray diffraction(XRD) and scanning electron microscope(SEM),respectively.The as-prepared LiNi1/3Co1/3Mn1/3O2 shows a layered α-NaFeO2 structure;the particles are small and uniformly distributed.As compared with the sample prepared by traditional method,the present cathode material …


Electrochemical Behavior Of Co-Ru Composite In Alkaline Solution, Su-mei YAO, Guo-chun LI, Xue-ping GAO 2010 Institute of New Energy Material Chemistry,Nankai University,Tianjin 300071,China;

Electrochemical Behavior Of Co-Ru Composite In Alkaline Solution, Su-Mei Yao, Guo-Chun Li, Xue-Ping Gao

Journal of Electrochemistry

The electrochemical properties of Ru doped cobalt hydroxides synthesized via homogeneous chemical co-precipitation were investigated in 6 mol·L-1 KOH solution by galvanostatic charge-discharge process and cyclic voltammetry(CV).It is demonstrated that Ru doped cobalt hydroxides exhibited good capacitive characteristic and high specific capacitance.The sample with a Co/Ru molar ratio of 8 /1 shows the optimized electrochemical performance,including capacitive property and discharge capacity.The microstructure and morphology of the obtained Ru doped hydroxides were characterized by X-ray diffraction(XRD) and scanning electron microscope(SEM).The amorphous structure of ruthenium dioxide nanoparticles and single-crystal structure of Co(OH)2 platelets were confirmed.Based on a structure analysis and …


Cobalt-Doped Todorokite Prepared By Refluxing At Atmospheric Pressure As Lithium-Ion Battery Cathode, Rui-qi LI, Chun-hua SONG, Chao XU, Li-xing TU, Guo-hong QIU, Fan LIU 2010 Key Laboratory of Subtropical Agriculture Resource and Environment,Ministry of Agriculture,Huazhong Agricultural University,Wuhan430070,China;

Cobalt-Doped Todorokite Prepared By Refluxing At Atmospheric Pressure As Lithium-Ion Battery Cathode, Rui-Qi Li, Chun-Hua Song, Chao Xu, Li-Xing Tu, Guo-Hong Qiu, Fan Liu

Journal of Electrochemistry

Cobalt-doped todorokites were prepared by refluxing at atmospheric pressure,and then charactered by X-ray diffraction(XRD),thermogravimetry(TG) and the analysis of chemical compositions.These measurements showed that all of the refluxing products were single phase of todorokites and the structure formulas were MgxCoyMnOz·nH2O,where 0.18 ≤ x ≤ 0.22,0 ≤ y ≤ 0.24,2.10 ≤ z ≤ 2.53,and 0.35 ≤ n ≤0.73.The electrochemical characteristics of cobalt-doped todorokites were examined as lithium insertion hosts for cathodes in rechargeable lithium batteries.The first discharge capacity of undoped todorokite electrode was 211 mAh/g and the discharge capacity became 37 mAh/g after 30 …


Fabrication And Characterization Of The Ni-Scsz Composite Anodes With A Lscm-Ceo2 Catalyst Layer In Thin Film Sofc, Yun-yun WANG, Bo HUANG, Xin-jian ZHU, Wan-qi HU, Qing-chun YU 2010 Institute of Fuel Cell,Shanghai Jiaotong University,Shanghai 200240,China;

Fabrication And Characterization Of The Ni-Scsz Composite Anodes With A Lscm-Ceo2 Catalyst Layer In Thin Film Sofc, Yun-Yun Wang, Bo Huang, Xin-Jian Zhu, Wan-Qi Hu, Qing-Chun Yu

Journal of Electrochemistry

Solid oxide full cell(SOFC) running directly on hydrocarbon fuels has attracted much attention in recent years. In this paper, a dual-layer structure anode was fabricated by tape casting and screen printing method. The addition of a LSCM-CeO2 catalyst layer to the supported anode surface yielded better performance in ethanol fuel. The maximum power density reached 710 and 669 mW/cm2 at 850 ℃ running on hydrogen gas steam and ethanol steam,respectively. No significant degradation in performance has been observed after 216 h of cell testing when the Ni-ScSZ13 anode was exposed to the ethanol steam at 700 ℃. Very …


Self-Activating Safety Mechanisms For Li-Ion Batteries, Xin-ping AI, Yu-Liang CAO, Han-Xi YANG 2010 College of Chemistry and Molecular Sciences,Hubei Key Lab.of Eletrochemical Power Sources,Wuhan University,Wuhan 430072,China;

Self-Activating Safety Mechanisms For Li-Ion Batteries, Xin-Ping Ai, Yu-Liang Cao, Han-Xi Yang

Journal of Electrochemistry

The safety concerns of LIBs are considered to be a main obstacle to their high rate or large capacity applications in electric vehicles.This paper describes briefly our research works on the development of self-activating safety mechanisms for LIBs,including redox shuttle,potential-sensitive separator,temperature-sensitive electrode,and fire-retardent electrolyte.The problems and future in this research area are also discussed.


Preparation And Characterizations Of Li3V2(Po4)3 Cathode Material For Lithium Ion Batteries, Hong CHEN, Tao JIANG, Chun-zhong WANG, Gang CHEN, Ying-jin WEI 2010 College of Physics,Beihua University,Jilin 132013,Jilin,China;College of Materials Science and Engineering,Jilin University,Changchun 130012,China;

Preparation And Characterizations Of Li3V2(Po4)3 Cathode Material For Lithium Ion Batteries, Hong Chen, Tao Jiang, Chun-Zhong Wang, Gang Chen, Ying-Jin Wei

Journal of Electrochemistry

The carbon-coated Li3V2(PO4)3 was prepared by carbothermal reduction method.The structural and morphological properties of the material were studied by X-ray diffraction,FTIR and transmission electron microscopy.The synthesized material was a pure phase of Li3V2(PO4)3,with the particle size of about 100 nm.The values of Li ion diffusion coefficient of the material in the potential window of 3.0 ~ 4.3 V were nearly 3 orders larger than those in 3.0 ~ 4.8 V.In addition,the charge-transfer resistances in 3.0 ~ 4.3 V were much smaller than those in 3.0 …


Performance Of Sulfur-Super Conductive Carbon Black Composite In Electrolyte Mixed With Room Temperature Ionic Liquid, Bo ZHANG, Si-ting CHEN, Xue-ping GAO 2010 Institute of New Energy Material Chemistry,Nankai University,Tianjin 300071,China;

Performance Of Sulfur-Super Conductive Carbon Black Composite In Electrolyte Mixed With Room Temperature Ionic Liquid, Bo Zhang, Si-Ting Chen, Xue-Ping Gao

Journal of Electrochemistry

The sulfur-super conductive carbon black composite was prepared as cathode material of lithium/sulfur battery.The composite was characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),and electrochemical impedance spectroscopy(EIS).The sulfur composite shows a high discharge capacity and a good cycle performance in electrolyte mixed with 50% of room temperature ionic liquid.In particular,the discharge capacity of the composite was stabilized at 483.6 mAh/g after 50 cycles.


Electrochemical Properties Of Ni(Oh)2 Doped By Nio, Fei-biao CHEN, Bo-rong WU, Wei-feng AN, Zhao-jun YANG, Feng WU, Shi CHEN 2010 School of Chemical Engineering and Environmental Science,Beijing Institute of Technology,Beijing 100081,China;

Electrochemical Properties Of Ni(Oh)2 Doped By Nio, Fei-Biao Chen, Bo-Rong Wu, Wei-Feng An, Zhao-Jun Yang, Feng Wu, Shi Chen

Journal of Electrochemistry

The Ni(OH)2 cathode material of MH/Ni was doped by NiO,which behaves as a capacitor and can improve the charge-discharge rate capacity of Ni(OH)2.The electrochemical properties of Ni(OH)2 was characterized by charge-discharge curves and cyclic voltammetry.The results showed that the material had the best discharge property when doped by 5% NiO,and the discharge specific capacity could reach 310.1 mAh/g at 0.2 C rate and remianed 79.5% at 3 C rate.The difference oxidation and reduction potentials between the of the battery was 164 mV when the Ni(OH)2 was doped by 5% NiO,which showed a good cyclic property.


Electrosynthesis Of P-Aminobenzenearsenic Acid, Chun-an MA, Qin-an ZHENG, Qiang ZHOU, Ying-hua XU 2010 State Key Laboratory Breeding Base of Green Chemisitry Synthesis Technology,Zhejiang University of Technology,Hangzhou 310032,China;

Electrosynthesis Of P-Aminobenzenearsenic Acid, Chun-An Ma, Qin-An Zheng, Qiang Zhou, Ying-Hua Xu

Journal of Electrochemistry

The electrochemical reduction of p-nitrophenyl arsonit acid to p-aminobenzenearsenic acid was studied using controlled-current electrolysis.The results showed that the yield of p-aminobenzenearsenic acid was determinated by the following factors:the concentrations of sulphuric acid,the amount of additive,temperature and the concentrations of p-nitrophenyl arsenic acid.The optimum electrolytic conditions were obtained to be is 10% H2SO4,1% NaCl,80 ℃,25 g/350 mL p-nitrophenyl arsenic acid and 10 A·dm-2.The yield of arsanilic acid could be reached 64.7% under the optimum electrolytic conditions.


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