Electrical and Computer Engineering Commons^™

Effects Of Solvents And Electrolyte Salts On The Electrochemical Reduction Of Oxygen In Non-Aqueous Electrolytes, Yan-Yan Tian, Wei Wu, Jun Gao, Yong Yang

Journal of Electrochemistry

The electrochemical reduction processes of oxygen in different non-aqueous solvents such as acetonitrile(MeCN),propylene carbonate(PC) and their mixtures were investigated by cyclic voltammetry method.The results indicated a one electron reduction of oxygen to O^2-occured in these systems as a first step reduction,no matter whether in tetrabutylammonium hexafluorophosphate(TBAPF₆)/MeCN or TBAPF₆/PC electrolyte.However,the CV curves in 0.1 mol·L^-1 TBAPF₆/MeCN showed a couple of reversible redox peaks,indicating that the reduction process of oxygen was irreversible in the 0.1 mol·L^-1 TBAPF₆/PC electrolyte.In the PC-based electrolyte,the reduction current peak reduced largely and the oxidation peak …

Electrodeposition Of Lead Dioxide From Dluoroborate Solutions, Chun-Mei Kong, Yong-Ming Tang, Wen-Zhong Yang, Xiao-Yuan Yang

Journal of Electrochemistry

The PbO₂ anodes were prepared on platinum from fluoroborate media and its doped solutions by electrodeposition technique.Elecchemical and pysicochemical properties of these PbO₂ films were studied by cyclic voltammetry methods,XRD and SEM.The results showed that the presence of BF₄-increased PbO₂ electrodeposition rate;the prepared lead dioxide consisted of β-PbO₂;the preferential orientation of crystals and surface morphology were affected a lot by doping F-and Fe³⁺.The FB/F-Fe-PbO₂ electrode exhibited regular-shaped layers with compact morphology.Furthermore,increasing current density also change the preferential orientation of PbO₂ crystals.

Research On Nafion/Sio2 Composite Membrane In All Vanadium Redox Flow Battery, Dong-Dong Liu, Mao-Cai Lin, Tao Guan, Qing-Chun Yu

Journal of Electrochemistry

The Nafion117/SiO₂ composite membrane was prepared by sol-gel method.The results showed that,during composite membrane preparation process,the ratio of MeOH and TEOS did not affect the penetration rate of VO²⁺ basically,however,the lowest permeability of 427×10-9cm²/s in the membrane was achieved while hydrolysis time was 10 min and natural drying for 24 h after hydrolysis,which reduced by 52 times than that in Nafion117 membrane.The SEM tests proved that SiO₂ grains grew bigger in the composite membrane during the natural drying,and most of the holes in Nafion117 were filled.Single cell test showed the battery power efficiency was improved …

The Sol-Gel Synthesis And Electrochemical Performance Of Li3V2(Po4)3/C Cathode Material For Lithium Ion Battery, Li-Ying Liu, Lian Chen, Hai-Yan Zhang, Yu-Chun Zhai

Journal of Electrochemistry

Li₃V₂(PO₄)₃/C was synthesized by sol-gel method with citric acid as chelate and C sources. Physical and electrochemical performances of as-prepared materials were characterized through XRD, SEM and galvanostatic charge-discharge tests,etc. The results showed that products produced by calcining at 800 ℃ for 12 h had a single phase crystal structure and relatively small particle sizes with uniform distribution. At 0.1 C, 0.5 C and 1 C, the initial specific discharge capacities were 153.0, 143.1 and 130.6 mAh·g^-1, respectively, and capacity efficiencies were 93.1%, 85.4% and 77.3% after 50 cycles, respectively. …

A Bit Serial Approach To Massively Parallel Floating Point Operations On An Fpga, Duane Marcy, Fred Schlereth, Parija Kshirsagar, Anvith Katte Mahabalagiri

Electrical Engineering and Computer Science - All Scholarship

In this paper we discuss the pros and cons of bit serial arithmetic for performing mathematical operations for signal processing and scientific computations on an FPGA.  We describe our formulation of the architecture for such massively parallel systems, the advantage being that it requires no parallel programming in the traditional sense. We describe a pseudo floating point bit serial circuit which is less complex than full precision floating point and show that it is suitable for many applications. We conclude with several application examples and show that a bit serial implementation can be competitive with a high speed parallel implementation.

Bandwidth-Efficient Mimo Underwater Acoustic Communications With Frequency-Domain Equalization, Jian Zhang, Yahong Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a bandwidth-efficient frequency-domain equalization (FDE) for single carrier (SC) underwater acoustic (UWA) communications with multiple transducers and hydrophones. the proposed algorithm implements an overlapped-window FDE by partitioning a large block into small subblocks. a decision-directed channel estimation scheme is also proposed to track the channel variation by the detect symbols. the proposed algorithm is tested by undersea data collected during the Rescheduled Acoustic Communications Experiment (RACE) in March 2008. the experimental results demonstrate the proposed receive algorithm effectively tracks the time variation of the channel impulse responses and significantly improves the performance of uncoded bit error rate …

Turbo Detection For Mobile Mimo Underwater Acoustic Communications, Jun Tao, Yahong Rosa Zheng, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

Turbo detection for mobile transceivers is proposed for high data-rate single-carrier multiple-input, multiple-output (MIMO) underwater acoustic (UWA) communications. the proposed detection scheme employs a MIMO Doppler preprocessor and a low-complexity MIMO turbo linear equalizer (LE). the Doppler preprocessor estimates the motion-induced Doppler shift and compensates it via symbol resampling. the preprocessed signal is then detected by the MIMO turbo LE that utilizes soft-decision minimum mean square error (MMSE) linear equalization with maximum a posteriori probability (MAP) channel decoding, thus improving the detection performance iteratively while maintaining low complexity. the proposed turbo detection scheme has been tested by field trial data …

A New Statistical Procedure For Validation Of Simulation And Stochastic Models, Robert G. Sargent

Electrical Engineering and Computer Science - All Scholarship

We describe a new statistical procedure for validating simulation and analytic stochastic models using hypothesis testing when the amount of model accuracy is specified. This procedure provides for the model to be accepted if the difference between the system and the model outputs are within the specified ranges of accuracy. The system must be observable to allow data to be collected for validation.

Energy Storage And Management For A Small Series Plug-In Hybrid Electric Vehicle, Liqin Ni

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Plug-in hybrid electric vehicles (PHEVs) are gaining increasing interest for both residential and commercial transportation applications. In PHEV design, energy storage system (EES) is a critical component which will impact the overall design efficiency, performance, cost and etc. This dissertation aims to design an advanced energy storage system for a small plug-in hybrid electric vehicle, whose performance will approach very closely to the optimal possible, in terms of energy efficiency and acceleration, for passenger road vehicles application. Moreover, practical automotive requirements are considered during ESS design, such as cost, life time, safety and volume.

This dissertation utilizes ultracapacitors in conjunction …

Terminology Enhanced Ehr: Integration Of Archetypes And Terminology, An Implementation Experience, Sheng Yu, Damon Berry

Reports

The integration of terminology and EHR information models is an important step in the journey towards semantic interoperability. Archetypes and two-level models for EHRs provide a mechanism that not only applies constraints on clinical content but also ensures effective terminology binding. However the lack of a standardised mechanism to bind terminology to the EHR and the difficulty of systematically coding clinical content, has led to a number of possible implementation choices. This study presents a review of the problems that may occur when working with modern terminology systems and discusses some related state of art technologies. The paper aims to …

An Onboard Vision System For Unmanned Aerial Vehicle Guidance, Barrett Bruce Edwards

Theses and Dissertations

The viability of small Unmanned Aerial Vehicles (UAVs) as a stable platform for specific application use has been significantly advanced in recent years. Initial focus of lightweight UAV development was to create a craft capable of stable and controllable flight. This is largely a solved problem. Currently, the field has progressed to the point that unmanned aircraft can be carried in a backpack, launched by hand, weigh only a few pounds and be capable of navigating through unrestricted airspace. The most basic use of a UAV is to visually observe the environment and use that information to influence decision making. …

The Investment Comparison Tool (Ict): A Method To Assess Research And Development Investments, Tiffany A. Sargent, Robert G. Sargent

Electrical Engineering and Computer Science - All Scholarship

This paper presents a software tool (the Investment Comparison Tool), a methodology (the Investment Comparison Methodology), and a decision support system (the Investment Comparison System) to aid decision makers with Research and Development Investment allocations. The Investment Comparison System (ICS) can be used vertically within an organization and horizontally across organizations at multiple portfolio investment levels. The ICS is applicable to any R&D environment ranging from Industry Research Environments to Federal Agencies. The ICS described in this paper is comprised of a system architecture, databases, Group Decision Making (GDM) methods, an Investment Comparison Tool (ICT) that includes various algorithms, and …

Nonlinear Observability Analysis Of Bearing-Only Cooperative Localization Using Graph Theory, Rajnikant Sharma

Faculty Publications

In this report we investigate the nonlinear observability properties of bearing-only cooperative localization. We establish a link between observability and a graph representing measurements and communication between the robots.

Nanoindentation And Plasticity In Nanocrystalline Ni Nanowires: A Case Study In Size Effect Mitigation, F. Sansoz, Virginie Rollin

Publications

We examine the processes of spherical indentation and tension in Ni nanowires and thin films containing random distributions of nanoscale grains by molecular dynamics simulations. It is shown that the resistance to nanoindentation of nanocrystalline Ni nanowires with diameters of 12 and 30 nm tends not to depend on the wire diameter and free surfaces, contrary to nanoindentation in single-crystalline nanowires. Accommodation of plastic deformation by grain boundary sliding suggests a mitigation strategy for sample boundary effects in nanoscale plasticity.

Observability Analysis Of Bearing-Only Cooperative Localization, Rajnikant Sharma

Faculty Publications

In this report we investigate the nonlinear observability properties of bearing-only cooperative localization. We establish a link between observability and a graph representing measurements and communication between the robots. It is shown that graph theoretic properties like the connectivity and the existence of a path between two nodes can be used to explain the observability of the system.

A New Ac-Dc Converter Using Bridgeless Sepic, M. R. Sahid, A. H. M. Yatim, Taufik

Electrical Engineering

A new bridgeless power factor correction circuit (PFC) based on single ended primary inductance converter (SEPIC) is proposed. The number of component conducted at each subinterval mode is reduced compared to the existing topologies. Analysis of the converter operated in discontinuous-conduction mode (DCM) is discussed. Experimental circuit for the proposed converter is developed with universal input voltage capability for 50V DC output voltage connected to 100W load. The simulation and experimental results are presented to show the performances of the proposed circuit.

Improved Rf Power Extraction From 1.55Μm Ge/Si N-I-P Photodiodes With Load Impedance Optimization, Andrew L. Huard, Molly Piels, Anand Ramaswamy, John E. Bowers, Dennis J. Derickson

Electrical Engineering

The RF output power of Ge/Si n-i-p waveguide photodetectors is improved by increasing the load impedance. The maximum extracted RF power at 3GHz is 17.13dBm with a compression current of 42mA using a 100Ὠ load.

A New Multiphase Multi-Interleaving Buck Converter With Bypass Lc, Taufik, Randyco Prasetyo, Dale Dolan, Dodi Garinto

Electrical Engineering

As the number of transistors in microprocessors increases, their power demand increases accordingly. This poses design challenges for their power supply module called VRM (Voltage Regulator Module) especially when operated at sub voltage range. This paper presents the design of a new multiphase multi-interleaving topology that addresses these challenges. A lab scaled hardware prototype of the new topology shows improved load regulation, output voltage ripple and dynamic response time compared to a commercially available power supply module.

Identification Of Psychological Patterns Using Neural Networks Approach, Panpan Hu

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Recent studies have shown that Artificial Neural Networks (ANNs) are suitable for recognizing patterns in the medical area. However, no study has been done to show whether or not they are also effective in the psychological area. In this study, ANNs are developed for six psychological cases related to sociobehavioral functioning. The cases are independent living skill deficits, disorder management deficits, occupational skill deficits, social skill deficits, dysregulation of anger/aggression, and substance abuse. Two models, one based on a backpropagation algorithm and the other based on a posteriori probability approach, were developed. The models were tested using data from 118 …

Mimo Channel Spatial Covariance Estimation: Analysis Using A Closed-Form Model, Yanling Yang

Theses and Dissertations

Multiple-input Multiple-output (MIMO) wireless communication systems allow increased spectral efficiency and therefore promise significant improvement in performance. However, because of the rapid variation in channel state information (CSI) in networks with mobile nodes or scatterers, it is difficult both to maintain high communication performance and to create channel models that effectively represent the time-varying behavior of the channels. The spatial covariance of the MIMO channel describes the average power gain on each transmit-receive antenna pair as well as the correlation between the complex link gains and thus provides critical information for understanding the performance of the system and for creating …

Wimax Implementation As Existing Hotspot Network Backhaul In Jakarta, Djamhari Sirat, Muhamad Asvial, Luther B. Marpaung

Makara Journal of Technology

WiMAX Implementation as Existing Hotspot Network Backhaul in Jakarta The development of Broadband Wireless Access (BWA), such as WiMAX, as a global standard for data transmission media has been used by high speed internet access provider. WiMAX application which supported by capabilities of interoperability, flexibility and commercial aspect make the internet services become more efficient, cheaper and easier to the customer. This phenomenon should be responded by ISPs. Based on technical and financial aspect in deciding the implementation of Wireless Network with WiMAX technology as a substitute, this research will observe and analyze the projection of WiMAX technology implementation as …

Plant Growth Modeling Using L-System Approach And Its Visualization, Atris Suyantohadi, Alfiyan Alfiyan, Mochamad Hariadi, Mauridhi Hery Purnomo

Makara Journal of Technology

The visualization of plant growth modeling using computer simulation has rarely been conducted with Lindenmayer System (L-System) approach. L-System generally has been used as framework for improving and designing realistic modeling on plant growth. It is one kind of tools for representing plant growth based on grammar sintax and mathematic formulation. This research aimed to design modeling and visualizing plant growth structure generated using L-System. The environment on modeling design used three dimension graphic on standart OpenGL format. The visualization on system design has been developed by some of L-System grammar, and the output graphic on three dimension reflected on …

Immobilization Of Saccharomyces Cerevisiae In Rice Hulls For Ethanol Production, Edita Martini, Dian Andriani, Sriramulu Gobikrishnan, Kyeong Eop Kang, Surn-Teh Bark, Changshin Sunwoo, Bambang Prasetya, Don-Hee Park

Makara Journal of Technology

The whole cell immobilization in ethanol fermentation can be done by using natural carriers or through synthetic carriers. All of these methods have the same purpose of retaining high cell concentrations within a certain defined region of space which leads to higher ethanol productivity. Lignocellulosic plant substance represents one of highly potential sources in ethanol production. Some studies have found that cellulosic substances substances can also be used as a natural carrier in cell immobilization by re-circulating pre-culture medium into a reactor. In this experiment, rice hulls without any treatment were used to immobilize Saccharomyces cerevisiae through semi solid state …

Separation Study Of Titanomagnetite Fe3-Xtixo4 From Natural Sand At Indramayu, West Java, Sunaryo Sunaryo, Iwan Sugihartono

Makara Journal of Technology

Separation Study of Titanomagnetite Fe3-xTixO4 from Natural Sand at Indramayu, West Java. Titanomagnetite FeTiO4 has been obtained from metal sand which is separated from natural sand at Indramayu using magnetic separator with the magnetic field 0,3 Tesla. This method can improve titanomagnetite content from 32% to 63,6%. According to X-ray diffractometer (XRD) and data processing by general structure analyses system (GSAS) with χ2= 1,454 and Wrp = 0,1142 as correction factor of the peak to peak intensities, we conclude that χ2 about 0 and Wrp aproximately 10%. It indicates the datas with the error merely 0,1 can be accepted. Furthermore, …

Hydrogen Absorption Induced Slow Crack Growth In Austenitic Stainless Steels For Petrochemical Pressure Vessel Industries, Ronnie Higuchi Rusli

Makara Journal of Technology

Type 304L and type 309 austenitic stainless steels were tested either by exposed to gaseous hydrogen or undergoing polarized cathodic charging. Slow crack growth by straining was observed in type 304L, and the formation of α‘ martensite was indicated to be precursor for such cracking. Gross plastic deformation was observed at the tip of the notch, and a single crack grew slowly from this region in a direction approximately perpendicular to the tensile axis. Martensite formation is not a necessary condition for hydrogen embrittlement in the austenitic phase.

Simulation On The Use Of Losat Data For Rice Field Mapping, Bambang H. Trisasongko, Dyah R. Panuju, Boedi Tjahjono, Baba Barus, Hari Wijayanto, Mahmud A. Raimadoya, Irzaman Irzaman

Makara Journal of Technology

Simulation on the Use of LOSAT Data for Rice Field Mapping. Since the launch of LAPAN-TUBSAT satellite in 2007, Indonesia has been developing mission on earth observation missions for various applications. The next generation mission, called LAPAN-ORARI Satellite (LOSAT), is currently under development and expected to be launched in 2011. In order to facilitate the applications, a thorough assessment of the sensor should be made. This paper presents an examination of simulated LOSAT data for rice monitoring and mapping purposes coupled with QUEST statistical tree. We found that three-band simulated LOSAT data were suitable for the task with reasonably high …

Development Of Technology Parameter Towards Shipbuilding Productivity Predictor Using Cubic Spline Approach, Bagiyo Suwasono, Sjarief Widjaja, Achmad Zubaydi, Zaed Yuliadi, I Nyoman Budiantara

Makara Journal of Technology

Development of Technology Parameter Towards Shipbuilding Productivity Predictor Using Cubic Spline Approach. Ability of production processes associated with state-of-the-art technology, which allows the shipbuilding, is customized with modern equipment. It will give impact to level of productivity and competitiveness. This study proposes a nonparametric regression cubic spline approach with 1 knot, 2 knots, and 3 knots. The application programs Tibco Spotfire S+ showed that a cubic spline with 2 knots (4.25 and 4.50) gave the best result with the value of GCV = 56.21556, and R2 = 94.03%.Estimation result of cubic spline with 2 knots for the PT. Batamec shipyard …

Shaft Torsional Vibration Response Of Vertical Axis Ocean Current Turbine Model Due To Torque Excitation, Adi Wirawan Husodo, I Ketut Aria Pria Utama, I Made Ariana

Makara Journal of Technology

Shaft Torsional Vibration Response of Vertical Axis Ocean Current Turbine Model Due to Torque Excitation. The current research aimed to study the torsional vibration response of Vertical Axis Ocean Current Turbine due to randomly torque excitation pattern, owing to the variety of ocean current velocity. The turbine model is composed of 3 aluminum blades of NACA 0018 connected to steel shaft. Turbine dimensions are 10 cm of chord, 1.8 cm of chamber and 100 cm of span. The variation of ocean current velocity is 0.5 m/s, 1.0 m/s, 1.5 m/s, 2.0 m/s, 2.5 m/s and 3.0 m/s. The Model has …

Dye Sensitized Solar Cell With Conventionally Annealed And Post-Hydrothermally Treated Nanocrystalline Semiconductor Oxide Tio2 Derived From Sol-Gel Process, Akhmad Herman Yuwono, Badrul Munir, Alfian Ferdiansyah, Arif Rahman, Wulandari Handini

Makara Journal of Technology

Dye-sensitized solar cell (DSSC) is one of the very promising alternative renewable energy sources to anticipate the declination in the fossil fuel reserves in the next few decades and to make use of the abundance of intensive sunlight energy in tropical countries like Indonesia. In the present study, TiO2 nanoparticles of different nanocrystallinity was synthesized via sol−gel process with various water to inorganic precursor ratio (Rw) of 0.85, 2.00 and 3.50 upon sol preparation, followed with subsequent drying, conventional annealing and post-hydrothermal treatments. The resulting nanoparticles were integrated into the DSSC prototype and sensitized with an organic dye made of …

An Empirical Model For Build-Up Of Sodium And Calcium Ions In Small Scale Reverse Osmosis, Subriyer Nasir

Makara Journal of Technology

A simple models for predicting build-up of solute on membrane surface were formulated in this paper. The experiments were conducted with secondary effluent, groundwater and simulated feed water in small-scale of RO with capacity of 2000 L/d. Feed water used in the experiments contained varying concentrations of sodium, calcium, combined sodium and calcium. In order to study the effect of sodium and calcium ions on membrane performance, experiments with ground water and secondary effluent wastewater were also performed. Build-up of salts on the membrane surface was calculated by measuring concentrations of sodium and calcium ions in feed water permeate and …