Engineering Commons^™

Effective Ionic Conductivity Of A Novel Intermediate-Temperature Mixed Oxide-Ion And Carbonate-Ion Conductor, Xue Li, Guoliang Xiao, Kevin Huang

Faculty Publications

A systematic investigation on the effective ionic conductivity (σ_m) of a novel intermediate-temperature mixed oxide-ion and carbonate-ion conductor MOCC consisting of a ceria phase and a carbonate phase is reported. The study explicitly shows that the observed remarkable temperature-dependent σ_m is primarily the result of softening/melting of the carbonate phase as the physical state of the carbonate phase transforms from solid, softened to molten. Differential scanning calorimetry analysis complements the understanding of the observed electrical behavior by revealing temperatures of melting and solidification in agreement with the onset temperatures of σ_m. In addition, the …

Moving Ground Target Tracking In Urban Terrain Using Air/Ground Vehicles, Timothy Mclain, Randal W. Beard, Mark Owen, Huili Yu

Faculty Publications

In this paper, we present a framework for tracking a moving target in urban environments using UAVs in cooperation with UGVs. The framework takes into account occlusions between the sensor and the target. The target state is modeled using the dynamic occupancy grid and the target motion model is built using a second-order Markov chain. Based on the target occupancy grid, we design the path planning algorithm to maneuver the UAV and the UGV to configurations where they can detect the target with high probability. Simulation results show the framework is successful in solving the target tracking problem in urban …

Optimization Design Of Electrodes For Anode-Supported Solid Oxide Fuel Cells Via Genetic Algorithm, Junxiang Shi, Xingjian Xue

Faculty Publications

Porous electrode is the critical component of solid-oxide fuel cells (SOFCs) and provides a functional material backbone for multi-physicochemical processes. Model based electrode designs could significantly improve SOFC performance. This task is usually performed via parameter studies for simple case and assumed property distributions for graded electrodes. When nonlinearly coupled multiparameters of electrodes are considered, it could be very difficult for the model based parameter study method to effectively and systematically search the design space. In this research, the optimization approach with a genetic algorithm is demonstrated for this purpose. An anode-supported proton conducting SOFC integrated with a fuel supply …

Geometry-Dependent Oxygen Diffusion Flux And Limiting Current Density Of The Cathode In A Cathode-Supported Solid Oxide Fuel Cell, Kevin Huang, James L. Shull

Faculty Publications

An analysis is performed on the diffusion of oxygen through tubular porous cathode substrates having several different geometries. It is shown that the flux of oxygen as it diffuses through these different substrate geometries can be explicitly expressed by a general analytical form with a unique geometric factor for each type of substrate geometry. Experimental measurements of the geometry-independent term, oxygen diffusivity, were conducted for two representative geometries: cylindrical and triangular tubes. These measurements show good agreement between samples with similar porosities and thus favorably support the oxygen flux equations presented. Formulations for the limiting current density were also derived …

Error Correcting Codes For Cooperative Broadcasting, Robert H. Morelos-Zaragoza

Faculty Publications

This talk considers the design and implementation of error correcting codes for cooperative broadcasting in wireless networks. Focus is on the case of two cooperating sources transmitting two classes of information to a single receiver. This case was first introduced in the seminal work of Bergmans and Cover and referred to as "over the air mixing". Two levels of protection are provided using two low-density parity-check (LDPC) codes combined using Plotkin's |u|u+v|-construction. Expressions are derived for the bit metrics used in iterative decoding for two-level codes combined with BPSK, QPSK and 4-PAM modulations. Several examples of codes and their performance …

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.

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.

Structures Of Human Thymidylate Synthase R163k With Dump, Fdump And Glutathione Show Asymmetric Ligand Binding, Lydia M. Gibson, Lesa R. Celeste, Leslie L. Lovelace, Lukasz Lebioda

Faculty Publications

Thymidylate synthase (TS) is a well validated target in cancer chemotherapy. Here, a new crystal form of the R163K variant of human TS (hTS) with five subunits per asymmetric part of the unit cell, all with loop 181-197 in the active conformation, is reported. This form allows binding studies by soaking crystals in artificial mother liquors containing ligands that bind in the active site. Using this approach, crystal structures of hTS complexes with FdUMP and dUMP were obtained, indicating that this form should facilitate high-throughput analysis of hTS complexes with drug candidates. Crystal soaking experiments using oxidized glutathione revealed that …

Doping Dependence Of Electronic And Mechanical Properties Of Gase1−XTeX And Ga1−XInXSe From First Principles, Zs. Rak, S. D. Mahanti, K. C. Mandal, N. C. Fernelius

Faculty Publications

No abstract provided.

Selection And Recognition Of Landmarks Using Terrain Spatiograms, Damian M. Lyons

Faculty Publications

A team of robots working to explore and map an area may need to share information about landmarks so as to register their local maps and to plan effective exploration strategies. In previous papers we have introduced a combined image and spatial representation for landmarks: terrain spatiograms. We have shown that for manually selected views, terrain spatiograms provide an effective, shared representation that allows for occlusion filtering and a combination of multiple views.

In this paper, we present a landmark saliency architecture (LSA) for automatically selecting candidate landmarks. Using a dataset of 21 outdoor stereo images generated by LSA, we …

Measurement And Modeling Of Infrared Nonlinear Absorption Coefficients And Laser-Induced Damage Thresholds In Ge And Gasb, Torrey J. Wagner, Matthew J. Bohn, Ronald A. Coutu Jr., L. P. Gonzales, J. M. Murray, K. L. Schepler, S. Guha

Faculty Publications

Using a simultaneous fitting technique to extract nonlinear absorption coefficients from data at two pulse widths, we measure two-photon and free-carrier absorption coefficients for Ge and GaSb at 2.05 and 2.5 µm for the first time, to our knowledge. Results agreed well with published theory. Single-shot damage thresholds were also measured at 2.5 µm and agreed well with modeled thresholds using experimentally determined parameters including nonlinear absorption coefficients and temperature dependent linear absorption. The damage threshold for a single-layer Al₂O₃ anti-reflective coating on Ge was 55% or 35% lower than the uncoated threshold for picosecond or nanosecond …

Qpsk And Oqpsk In Frequency Nonselective Fading, Michael D. Rice

Faculty Publications

The maximum likelihood estimator for the fading gain in a frequency non-selective fading channel is derived and analyzed for offset QPSK (OQPSK). The corresponding impact of estimator errors on the bit error probability performance for OQPSK is also derived.

Sql Querie Recommendations: A Query Fragment-Based Approach, Jayad Akbarnejad, Magdalini Eirinaki, Suju Koshy, Duc On, Neoklis Polyzotis

Faculty Publications

Relational database systems are becoming increasingly popular in the scientific community to support the interactive exploration of large volumes of data. In this scenario, users employ a query interface (typically, a web-based client) to issue a series of SQL queries that aim to analyze the data and mine it for interesting information. First-time users, however, may not have the necessary knowledge to know where to start their exploration. Other times, users may simply overlook queries that retrieve important information. In this work we describe a framework to assist non-expert users by providing personalized query recommendations. The querying behavior of the …

Personal Vs. Social, Magdalini Eirinaki

Faculty Publications

The last few years we witnessed an impressive growth in social networks and in applications that add value to their amassed information. At the same time, the continuing expansion of mobile platforms and applications (e.g. iPhone), combined with the overwhelming supply of information and services, makes effective personalization and context-awareness much required features. One may consider "personal" and "social" data management as comprising two distinct directions with conflicting characteristics. However, it can be argued that they complement each other and that in future applications they will ultimately converge. This "personal vs. social" predicament presents a number of interesting topics that …

The Electronic Structure And Secondary Pyroelectric Properties Of Lithium Tetraborate, Volodymyr T. Adamiv, Yaroslav V. Burak, David J. Wooten, John W. Mcclory, James C. Petrosky, Ihor Ketsman, Ya B. Losovyj, Peter A. Dowben, Jie Xiao

Faculty Publications

We review the pyroelectric properties and electronic structure of Li₂B₄O₇(110) and Li₂B₄O₇(100) surfaces. There is evidence for a pyroelectric current along the [110] direction of stoichiometric Li₂B₄O₇ so that the pyroelectric coefficient is nonzero but roughly 10³ smaller than along the [001] direction of spontaneous polarization. Abrupt decreases in the pyroelectric coefficient along the [110] direction can be correlated with anomalies in the elastic stiffness contributing to the concept that the pyroelectric coefficient is not simply a vector but has qualities of …

Cathode Polarizations Of A Cathode-Supported Solid Oxide Fuel Cell, Kevin Huang, Alessandro Zampieri, Martin Ise

Faculty Publications

The concentration, activation, and total polarizations of the cathode in a cathode-supported solid oxide fuel cell (SOFC) were theoretically and experimentally investigated. In the theoretical analysis, the exchange current density of the charge transfer was considered to be dependent on the P_O2 determined by the preceding O₂ diffusion, resulting in an interrelationship between activation and concentration polarizations. The established nonlinear polarization equations were then applied to solve the key parameters with area specific resistances and overpotentials of the polarizations experimentally measured by electrochemical impedance spectroscopy on an operating cathode-supported SOFC. To ensure the consistency and meaningfulness of …

Energy Harvesting And Mission Effectiveness For Small Unmanned Air Vehicles, Mark J. Cutler, Timothy W. Mclain, Randal W. Beard, Brian Capozzi

Faculty Publications

This paper explores the feasibility of improving unmanned air vehicle (UAV) mission effectiveness by extracting energy from the atmosphere. Specifically, we consider an aerial surveillance mission in the vicinity of a geographic ridge. Cross winds owing over the ridge produce regions of lift on the windward side that can be exploited to increase mission duration. Mission effectiveness is quantified using the seeability metric. Simulation results are presented for several observation target placements. Results indicate that seeability and imaging persistence can be improved by exploiting ridge lift. Simulations demonstrated that targets at ranges less than four times the ridge height were …

Modelling And Verification Of Response Of Rc Slabs Strengthened In Flexure With Mechanically Fastened Frp Laminates, Annalisa Napoli, Fabio Matta, Enzo Martinelli, Antonio Nanni, Roberto Realfonzo

Faculty Publications

Mechanically fastened fibre-reinforced polymer laminate systems are emerging as a promising means for the repair and strengthening of reinforced concrete members. This technology entails the use of pultruded carbon- and glass- vinyl ester fibre-reinforced polymer laminates with enhanced longitudinal bearing strength that are connected to the concrete substrate by means of steel anchors. Attractive applications are those for emergency repairs where constructability and speed of installation are critical requirements. In this paper, an experimental investigation is first presented that included laboratory testing of scaled reinforced concrete slabs strengthened with four different combinations of laminate lengths and fastener layouts to study …

Analytical Solutions For Efficient Interpretation Of Single-Well Push-Pull Tracer Tests, Junqi Huang, John A. Christ, Mark N. Goltz

Faculty Publications

Single-well push-pull tracer tests have been used to characterize the extent, fate, and transport of subsurface contamination. Analytical solutions provide one alternative for interpreting test results. In this work, an exact analytical solution to two-dimensional equations describing the governing processes acting on a dissolved compound during a modified push-pull test (advection, longitudinal and transverse dispersion, first-order decay, and rate-limited sorption/partitioning in steady, divergent, and convergent flow fields) is developed. The coupling of this solution with inverse modeling to estimate aquifer parameters provides an efficient methodology for subsurface characterization. Synthetic data for single-well push-pull tests are employed to demonstrate the utility …

A Genome-Wide Analysis Reveals No Nuclear Dobzhansky-Muller Pairs Of Speciation Genes Between S. Cerevisiae And S. Paradoxus, But Suggests More Complex Incompatibilities, Katy Kao, Katja Schwartz, Gavin Sherlock

Faculty Publications

The Dobzhansky-Muller (D-M) model of speciation by genic incompatibility is widely accepted as the primary cause of interspecific postzygotic isolation. Since the introduction of this model, there have been theoretical and experimental data supporting the existence of such incompatibilities. However, speciation genes have been largely elusive, with only a handful of candidate genes identified in a few organisms. The Saccharomyces sensu stricto yeasts, which have small genomes and can mate interspecifically to produce sterile hybrids, are thus an ideal model for studying postzygotic isolation. Among them, only a single D-M pair, comprising a mitochondrially targeted product of a nuclear gene …

A Miniature Energy Harvesting Device For Wireless Sensors In Electric Power System, Rashed H. Bhuiyan, Roger A. Dougal, Mohammod Ali

Faculty Publications

A novel energy harvesting device called the energy coupler is proposed which can provide power to small wireless sensors in a power system. The energy coupler when coupled electromagnetically to a nearby current carrying conductor scavenges ac power from the conductor. The proposed energy coupler converts the harvested ac power into dc using a passive voltage multiplier circuit. The design of the energy coupler is such that the dc power obtained is adequate to charge a miniature 1.2-V rechargeable battery. It is demonstrated that the energy coupler is capable of delivering 10 mW of dc power to a 50-Ω load. …

Development Of A Technological Literacy Course For Non-Engineering Students: Science Of High Technology, Thomas Howell, Patricia Backer, Belle Wei

Faculty Publications

As citizens, we are confronted by many global and national issues such as the dangers of greenhouse gases and the best choices for energy sources. These questions are fundamentally technical in nature and many people feel ill-equipped to understand the variety of claims and counterclaims as to what is “the truth” on these and other important scientific issues. For many people, the reaction is to give up and accept that the modern world is too complex to understand. To address these issues and improve technological literacy, the College of Engineering (CoE) at San José State University (SJSU) has implemented a …

Hispanic Computer Brigade Silicon Valley Computer Camp, Patricia Backer, Belle Wei

Faculty Publications

Hispanic students are vastly underrepresented in computing during a time when the Hispanic population in the U.S. is growing dramatically. By 2020, Hispanics will account for 50% of the workers in California. And, by 2050, the Hispanic population is projected to triple in the United States with 25% of the U.S. population being of Hispanic origin. The College of Engineering (CoE) at San José State University proposed a new approach for recruiting Hispanic students into computing disciplines and careers through the Hispanic Computer Brigade (HCB) initiative. By forming HCBs in two local high schools, we aimed to inspire and engage …

5 Ghz Band Vehicle-To-Vehicle Channels: Models For Multiple Values Of Channel Bandwidth, Qiong Wu, David W. Matolak, Indranil Sen

Faculty Publications

In Sen and Matolak's earlier paper, 5-GHz-band vehicle-to-vehicle (V2V) channel models were presented for channel bandwidths of 5 and 10 MHz. In this paper, we provide additional tapped delay line models for bandwidths of 1, 20, 33.33, and 50 MHz based upon the data used in Sen and Matolak's paper. We provide tables of channel parameters for five types of V2V channel classes and also include example tap correlation coefficients. Root-mean-square delay spread values are summarized, as are values of bandwidth for which the channel frequency correlation takes values of 0.7 and 0.5. As with the results from Sen and …

Stochastic Feature Selection With Distributed Feature Spacing For Hyperspectral Data, Jeffrey D. Clark, Michael J. Mendenhall, Gilbert L. Peterson

Faculty Publications

Feature subset selection is a well studied problem in machine learning. One short-coming of many methods is the selection of highly correlated features; a characteristic of hyperspectral data. A novel stochastic feature selection method with three major components is presented. First, we present an optimized feature selection method that maximizes a heuristic using a simulated annealing search which increases the chance of avoiding locally optimum solutions. Second, we exploit local cross correlation pair-wise amongst classes of interest to select suitable features for class discrimination. Third, we adopt the concept of distributed spacing from the multi-objective optimization community to distribute features …

High Temperature Water Gas Shift Catalysts With Alumina, Morris D. Argyle, Tiberiu Popa, Guoqing Xu, Thomas F. Barton

Faculty Publications

Alumina (Al2O3) was added as a component of conventional iron oxide based high temperature water gas shift (WGS) catalysts. The catalysts contained Fe-Al-Cr-Cu-O and were synthesized by coprecipitation. A series of catalysts were prepared with 5 to 50 wt% Al2O3, 8 wt% Cr2O3, 4 wt% CuO, and the balance Fe2O3. One catalyst was prepared in which the chromia was replaced by alumina. All of the catalysts were compared to a reference WGS catalyst (88 wt% FeOX, 8 wt% Cr2O3, and 4 wt% CuO) with no alumina. The catalysts were characterized using temperature programmed reduction (TPR), surface area analysis using nitrogen …

Detection And Filtering Of Landmark Occlusions Using Terrain Spatiograms, Damian M. Lyons

Faculty Publications

A team of robots cooperating to quickly produce a map needs to share landmark information between members so that the local maps can be accurately merged. However, the appearance of landmarks as seen by members of the team can change dramatically due to the phenomenon of occlusion.

We have previously presented an approach to landmark representation using Terrain Spatiograms – an extension to image spatiograms in which the spatial information relates to the scene rather than the image. Because this representation preserves depth structure, it is possible to identify and filter potential occlusions.

We present an approach to identifying and …

A Visual Imagination Approach To Cognitive Robotics, Damian M. Lyons, Sirhan Chaudhry, D. Paul Benjamin

Faculty Publications

No abstract provided.

Summary Of Feedback Edge Set Papers, Jonathan Johnson

Faculty Publications

The problem of finding a set of edges F from a directed graph G = (V,E) such that the graph G0 = (V,E − F) contains no cycles is known as the feedback edge set (FES) problem or the feedback arc set problem. A related problem is the minimum feedback edge set problem, in which the feedback edge set F must be minimal. The feedback edge set problem has application in applying a common reliability technique called triple modular redundancy to FPGA circuit designs where configuration memory scrubbing is employed [1].

Integrating Perception And Problem Solving To Predict Complex Object Behaviors, Damian M. Lyons, Sirhan Chaudhry, Marius Agica, John Vincent Monaco

Faculty Publications

One of the objectives of Cognitive Robotics is to construct robot systems that can be directed to achieve realworld goals by high-level directions rather than complex, low-level robot programming. Such a system must have the ability to represent, problem-solve and learn about its environment as well as communicate with other agents. In previous work, we have proposed ADAPT, a Cognitive Architecture that views perception as top-down and goaloriented and part of the problem solving process.

Our approach is linked to a SOAR-based problem-solving and learning framework. In this paper, we present an architecture for the perceptive and world modelling components …