Digital Commons Network^™

High School Dropout : Educators' Knowledge Of And Perceived Role In Dropout Prevention, Dustin Reese

Dissertations and Theses @ UNI

The reasons behind high school dropout have been examined for years. Previous research has focused primarily on understanding student characteristics in relation to high school dropout. However, teachers play an important role in preventing school dropout. Their beliefs about dropout may influence the way in which they interact with students, especially those they believe are at risk for dropout. Because of the critical influence teachers can have on students' educational decisions, this research sought to answer the following questions: (1) What factors do educators believe contribute to students' decision to drop out of school? and (2) What type of influence …

(Un)Gendered Sentiments: The Relationship Between Modernism And Gender In The Works Of Barnfield And Woolf, Brittany Kay Jungck

Dissertations and Theses @ UNI

By examining the history of literature through the lens of a gender critic, a person is able to discern how society and history frame our understanding of certain concepts. In this study, I have examined the lives and works of Richard Barnfield, a famed poet from the English Renaissance, and Virginia Woolf, a noted twentieth-century British novelist. The analysis of various aspects of Barnfield's and Woolf's creations reveals a connection between gendered language and modernity.

Angular Distributions From Photoionization Of H₂⁺, J. Colgan, O. Al-Hagan, Jerry Peacher, Don H. Madison, M. S. Pindzola, M. Foster

Physics Faculty Research & Creative Works

A study is made of the differential cross sections arising from the photoionization of H2+. Previous studies indicated surprising differences in the shapes of the angular distributions calculated from exterior complex scaling and 2C methods. To further explore these differences, we have calculated the angular distributions from the photoionization of H2+ using an independent two-body Coulomb function (2C) method and a distorted wave approach. As a final test, we also present calculations using a time-dependent technique. Our results confirm the discrepancies found previously and we present possible reasons for these differences.

Differential Double Capture Cross Sections In P+He Collisions, Michael Schulz, T. Vajnai, J. A. Brand

Physics Faculty Research & Creative Works

We have measured differential double capture cross sections for 15 to 150 keV p+He collisions. We also analyzed differential double to single capture ratios, where we find pronounced peak structures. An explanation of these structures probably requires a quantum-mechanical description of elastic scattering between the projectile and the target nucleus. Strong final-state correlations have a large effect on the magnitude of the double capture cross sections

Effects Of The Final-State Electron-Ion Interactions On The Fully Differential Cross Sections For Heavy-Particle-Impact Ionization Of Helium, Don H. Madison, Jerry Peacher, M. Foster, K. Bartschat, H. P. Saha, Allison L. Harris

Physics Faculty Research & Creative Works

Three-dimensional fully differential cross sections for heavy-particle-impact ionization of helium are examined. Previously, the three-body distorted-wave (3DW) model has achieved good agreement with experiment in the scattering plane for small momentum transfers, but poor agreement for large momentum transfers. Poor agreement was also observed outside the scattering plane for all momentum transfers. In particular, the 3DW calculations predicted cross sections that were too small both perpendicular to the scattering plane and for large momentum transfers. The important unanswered question concerns the physical effects that cause the significant disagreement between experiment and theory. In previous works, the role of the projectile-ion …

Electronic Band Structure And Carrier Effective Mass In Calcium Aluminates, Julia E. Medvedeva, E. N. Teasley, M. D. Hoffman

Physics Faculty Research & Creative Works

First-principles electronic band structure investigations of five compounds of the CaO-Al2O3 family, 3CaO·Al2O3, 12CaO·7Al2O3, CaO·Al2O3, CaO·2Al2O3, and CaO·6Al2O3, as well as CaO and alpha-, theta-, and kappa-Al2O3 are performed. We find that the conduction band in the complex oxides is formed from the oxygen antibonding p states and, although the band gap in Al2O3 is almost twice larger than in CaO, the s states of both cations. Such a hybrid nature of the conduction band leads to isotropic electron effective masses which are nearly the same for all compounds investigated. This insensitivity of the effective mass to variations in the …

Reconciliation Of Measured Fully Differential Single Ionization Data With The First Born Approximation Convoluted With Elastic Scattering, Michael Schulz, M. Dürr, B. Najjari, R. Moshammer, J. D. Ullrich

Physics Faculty Research & Creative Works

An analysis of experimental fully differential data for single ionization in 100 MeV/amu C6++He collisions is reported. We present a convolution of the first Born approximation with elastic scattering by using an event generator technique. Furthermore, the calculation is convoluted with all known experimental resolutions. Our analysis shows that elastic scattering is a viable explanation for surprising structures observed in the fully differential cross sections outside the scattering plane. Furthermore, it may even explain discrepancies in the “recoil peak” frequently observed for both ion and electron impact.

Screened-Exchange Determination Of The Electronic Properties Of Monoclinic, Tetragonal And Cubic Zirconia, Julia E. Medvedeva, C. B. Geller, D. M. Rishel, Arthur J. Freeman

Physics Faculty Research & Creative Works

First-principles electronic band structure investigations of monoclinic, tetragonal, and cubic ZrO2 reveal the highly anisotropic nature of the conduction and valence band topologies in the monoclinic phase with electron and hole effective masses differing by over an order of magnitude in perpendicular directions. The planes of relatively high implied electron and hole mobilities intersect along a single crystallographic direction, making this the only direction readily available for exciton motion. Conversely, in the tetragonal and cubic phases, charge carrier effective masses are more isotropic and exciton motion is less restricted. These findings may explain recent experimental observations suggesting that exciton production …

Validation Of The Suicide Resilience Inventory-25 (Sri-25) With Chinese And American College Students, Qijuan Fang

Dissertations and Theses @ UNI

This study examined the psychometric properties of the Suicide Resilience Inventory-25 (SRl-25; Osman et al., 2004) among Chinese and American college students. This instrument was designed to tap into the factors that help defend against suicidal thoughts and behaviors and includes three factors: Internal Protective (IP), External Protective (EP), and Emotional Control (EC). Three hundred and eighteen Chinese college students and 328 American college students completed the Chinese or English version of the SRI-25, the Multi-Attitude Suicide Tendency scale (MAST; Orbach et al., 1991), and the Suicide Behaviors Questionnaire-Revised (SBQ-R; Osman et al., 2001). American participants scored significantly higher on …

Breaking The Cycle-Preventing Failures By Leveraging Historical Data During Conceptual Design, Daniel A. Krus, Katie Grantham

Engineering Management and Systems Engineering Faculty Research & Creative Works

Major engineering accidents are often caused by seemingly minor failures propagating through complex systems. One example of this is an accident involving a Bell 206 Rotorcraft where a fuel pump failure led to the severing of the tail boom. Cataloguing and communicating the knowledge of potential failures and failure propagations is critical to prevent further accidents. The need for effective failure prevention tools is not specific to rotorcrafts, however. Failure reporting systems have been adopted by various industries to aid and promote failure prevention. The catalogued failures usually consist of narratives describing which part of a product failed, how it …

Greedy Population Sizing For Evolutionary Algorithms, Ekaterina Smorodkina, Daniel R. Tauritz

Computer Science Faculty Research & Creative Works

The number of parameters that need to be man ually tuned to achieve good performance of Evolutionary Algorithms and the dependency of the parameters on each other make this potentially robust and efficient computational method very time consuming and difficult to use. This paper introduces a Greedy Population Sizing method for Evolutionary Algo rithms (GPS-EA), an automated population size tuning method that does not require any population size related parameters to be specified or manually tuned a priori. Theoretical analysis of the number of function evaluations needed by the GPS EA to produce good solutions is provided. We also perform …

Verifying Noninterference In A Cyber-Physical System The Advanced Electric Power Grid, David Cape, Xiaoqing Frank Liu, Bruce M. Mcmillin, Yan Sun

Computer Science Faculty Research & Creative Works

The advanced electric power grid is a complex real-time system having both cyber and physical components. While each component may function correctly, independently, their composition may yield incorrectness due to interference. One specific type of interference is in the frequency domain, essentially, violations of the Nyquist rate. The challenge is to encode these signal processing problem characteristics into a form that can be model checked. To verify the correctness of the cyber-physical composition using model-checking techniques requires that a model be constructed that can represent frequency interference. In this paper, RT-PROMELA was used to construct the model, which was checked …

Wetting Kinetics Of A Thin Film Evaporating In Air, S. Saritha, Partho Neogi

Chemical and Biochemical Engineering Faculty Research & Creative Works

The conservation equation and the equations of motion are solved for a case where a thin liquid film moves out of a slot onto a horizontal surface. The liquid is allowed to evaporate into air. The evaporation process is taken to be isothermal. Lubrication theory approximation is used where only the tangential velocity and its dependence only in the normal direction are considered. The dynamics of thin films includes the use of disjoining pressure for a pure liquid and where there is a dissolved polymer. The results show that evaporation is quicker than film thinning such that a spreading regime …

Reinforcement Learning Based Output-Feedback Controller For Complex Nonlinear Discrete-Time Systems, Peter Shih, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

A novel reinforcement-learning based output-adaptive neural network (NN) controller, also referred as the adaptive-critic NN controller, is developed to track a desired trajectory for a class of complex feedback nonlinear discrete-time systems in the presence of bounded and unknown disturbances. This nonlinear discrete-time system consists of a second order system in nonstrict form and an affine nonlinear discrete-time system tightly coupled together. Two adaptive critic NN controllers are designed - primary one for the nonstrict system and the secondary one for the affine system. A Lyapunov function shows the uniformly ultimate boundedness (UUB) of the closed-loop tracking error, weight estimates …

Rfid Instrumentation In A Field Application, Theresa M. Swift, Martha J. Molander, Steve Eugene Watkins

Electrical and Computer Engineering Faculty Research & Creative Works

The behavior of radio-frequency identification (RFID) tags is investigated in a field application. The RFID instrumentation is used to mark the position of point strain sensors in a fiber-reinforced polymer (FRP), short-span bridge. The tags are surface mounted on carbon FRP structural elements and covered with a resin wear layer, i.e. the deck of the bridge. The smart composite bridge was installed in 2000 and serves as a field testbed for various sensor technologies including the RFID tags. The operation of the RFID network is tested in the field and compared to laboratory tags. Specific research issues include long-term survivability …

Sofc-Based Fuel Cells For Load Following Stationary Applications, Nagasmitha Akkinapragada, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a dynamic model of SOFC and the response of the fuel cell for sudden load changes. Slow response of the fuel cell prevents it from following the load, Hence connection with the DC/DC buck-boost converter is required. The models are developed in PSCAD with and without a feedback control system. Power characteristics obtained in order to validate the need of the DC/DC converter which allows the SOFC system to be used for load following applications

Spatial Diversity In Signal Strength Based Wlan Location Determination Systems, Anil Ramachandran, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

Literature indicates that spatial diversity can be utilized to compensate channel uncertainties such as multipath fading. Therefore, in this paper, spatial diversity is exploited for locating stationary and mobile objects in the indoor environment. First, space diversity technique is introduced for small scale motion and temporal variation compensation of received signal strength and it is demonstrated analytically that it enhances location accuracy. Small scale motion refers to movements of the transmitter and/or the receiver of the order of sub-wavelengths while temporal effects refer to environmental variations with time. A novel metric is introduced for selection combining in order to improve …

Training Winner-Take-All Simultaneous Recurrent Neural Networks, Xindi Cai, Danil V. Prokhorov, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

The winner-take-all (WTA) network is useful in database management, very large scale integration (VLSI) design, and digital processing. The synthesis procedure of WTA on single-layer fully connected architecture with sigmoid transfer function is still not fully explored. We discuss the use of simultaneous recurrent networks (SRNs) trained by Kalman filter algorithms for the task of finding the maximum among N numbers. The simulation demonstrates the effectiveness of our training approach under conditions of a shared-weight SRN architecture. A more general SRN also succeeds in solving a real classification application on car engine data.

Validation Of Worst-Case And Statistical Models For An Automotive Emc Expert System, Daryl G. Beetner, Haixiao Weng, Meilin Wu, Todd H. Hubing

Electrical and Computer Engineering Faculty Research & Creative Works

Previous papers have presented algorithms for an EMC expert system used to predict potential electromagnetic compatibility problems in a vehicle early in the design process. Here, the accuracy of inductive and capacitive coupling algorithms are verified through representative measurements of crosstalk within an automobile. Worst-case estimates used by the algorithms are compared to measured values and are compared to values estimated using statistical methods. The worst-case algorithms performed well up to 10-20 MHz, but overestimated measured results by several dB in some cases and up to 10-15 dB in others. An approximate statistical variation of the current expert system algorithms …

Wave Propagation On Power Cables With Special Regard To Metallic Screen Design, R. Papazyan, Per Pettersson, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

The high frequency properties of coaxial power cables are modeled using time- and frequency-domain numerical simulations. This is required due to the complex helical structure of the outer metallic screen. The finite element (FEM) and finite difference time domain methods (FDTD) have been employed to study the effect of screen spiralization. It is established that this screen design causes a dependence of the cable high frequency characteristics on the surrounding medium. Analytical model based on modal analysis of wave propagation in coaxial cables confirms the numerical observations.

An Online Approximator-Based Fault Detection Framework For Nonlinear Discrete-Time Systems, Balaje T. Thumati, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a fault detection scheme is developed for nonlinear discrete time systems. The changes in the system dynamics due to incipient failures are modeled as a nonlinear function of state and input variables while the time profile of the failures is assumed to be exponentially developing. The fault is detected by monitoring the system and is approximated by using online approximators. A stable adaptation law in discrete-time is developed in order to characterize the faults. The robustness of the diagnosis scheme is shown by extensive mathematical analysis and simulation results.

Application And Limits Of Ic And Pcb Scanning Methods For Immunity Analysis, Qing Cai, Jin Min, Giorgi Muchaidze, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

Immunity scanning methods can be used to locate sensitive areas on PCBs and ICs. For the analysis of emissions near field scanning is used to determine the local field strength. Both methods have many similarities and differences. For both methods it is difficult to correlate between board level scanning and system level test results as neither method shows the coupling path directly. The paper shows the implementation of an immunity scanning system and analyzes the advantages and limitations of immunity near field scanning.

Asymptotic Stability Of Nonholonomic Mobile Robot Formations Using Multilayer Neural Networks, Jagannathan Sarangapani, Travis Alan Dierks

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a combined kinematic/torque control law is developed for leader-follower based formation control using backstepping in order to accommodate the dynamics of the robots and the formation in contrast with kinematic-based formation controllers that are widely reported in the literature. A multilayer neural network (NN) is introduced along with robust integral of the sign of the error (RISE) feedback to approximate the dynamics of the follower as well as its leader using online weight tuning. It is shown using Lyapunov theory that the errors for the entire formation are asymptotically stable and the NN weights are bounded as …

A New Inverter For Improved Fuel Cell Performance In Grid-Tied Application, Nagasmitha Akkinapragada, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

The interconnection of a solid oxide fuel cell (SOFC) with the power conditioning units vis-à-vis a DC/DC converter and a DC/AC inverter for interfacing with the utility grid is presented. Fuel cells operate at low voltages and hence need to be boosted and inverted in order to be connected to the grid. The fuel cell and the DC/DC converter modeling are briefly explained. The methodology and the controller design for the control of power flow from the fuel cell to the utility grid are discussed. Power characteristics of the DC/AC inverter are compared with the characteristics of the DC/DC converter …

A Normalized Fractionally Lower-Order Moment Algorithm For Space-Time Adaptive Processing, Y. Rosa Zheng, Genshe Chen, Erik Blasch

Electrical and Computer Engineering Faculty Research & Creative Works

A new space-time adaptive processing algorithm is proposed for clutter suppression in phased array radar systems. In contrast to the commonly used normalized least mean square (NLMS) algorithm which uses the second order moments of the data for adaptation, the proposed method uses the lower order moments of the data to adapt the weight coefficients. The normalization is also performed based on the data sample dispersion rather than the variance. Processing results using simulated and measured data show that the proposed algorithm converges faster than the NLMS algorithms in Gaussian and non-Gaussian clutter environments. It also provides better clutter suppression …

A Proportional-Integrator Type Adaptive Critic Design-Based Neurocontroller For A Static Compensator In A Multimachine Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Yamille Del Valle, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

A novel nonlinear optimal controller for a static compensator (STATCOM) connected to a power system, using artificial neural networks, is presented in this paper. The action dependent heuristic dynamic programming, a member of the adaptive critic designs family is used for the design of the STATCOM neurocontroller. This neurocontroller provides optimal control based on reinforcement learning and approximate dynamic programming. Using a proportional-integrator approach, the proposed neurocontroller is capable of dealing with actual rather than deviation signals. Simulation results are provided to show that the proposed controller outperforms a conventional PI controller for a STATCOM in a small and large …

Channel Estimation And Phase-Correction For Robust Underwater Acoustic Communications, Y. Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a new channel estimation, equalization, and phase correction scheme to combat the convergence and stability problem encountered by time-domain adaptive equalizers in underwater acoustic communication systems. Large Doppler spread and symbol scaling in underwater channels have been challenging problems causing significant phase drift and performance degradation. Our new method targets this problem by first allowing phase errors in the estimation of the fading channel coefficients and then perform group-wise (rather than symbol-wise) phase estimation and correction after equalization and multiple channel combining. Single transmitter and multiple receiver data obtained through ocean experiments have been processed using the …

Asia Pacific Perspectives Vol. 7 No. 1, July 2007, University Of San Francisco, University Of San Francisco

Asia Pacific Perspectives

Contents:

Editor's Introduction by Joaquin L. Gonzalez III

Cross-Regional Trade Cooperation: The Mexico-Japan Free Trade Agreement by Sarita D. Jackson

Latin American and Asia-Pacific countries are fervently forging economic cooperative relationships, which began with the Asia-Pacific Economic Cooperation in 1989. The two regions have shifted away from looking intra-regionally for economic stability against the forces of globalization. Rather, they have moved towards emphasizing cross-regional trade pacts. Cross-regional trade pacts present a number of advantages for member countries. The Mexico-Japan FTA, as a case study, shows us that trade and FDI between member countries increase with cross-regional free trade agreements (FTA). …

A Growth Theory Perspective On The International Diffusion Of Electronic Commerce., S.C Ho, Robert John Kauffman, T.P. Liang

Research Collection School Of Computing and Information Systems

Information and communication technologies (ICTs) continue to have a profound effect on the economies and societies where they are used. In this article, we propose three related theories to describe the underlying mechanism for growth in e-commerce revenues at the national level. Endogenous growth theory posits that the primary drivers of e-commerce growth are internal to a country. Exogenous growth theory suggests that the primary drivers of e-commerce growth are external to an economic system, and reflect the forces of the regional economy. A blend of these, a mixed endogenous–exogenous growth theory, incorporates drivers from both the economy and …

Origin Of The Gang Name "Crips", Wilson Gray, Gerald Leonard Cohen

Arts, Languages and Philosophy Faculty Research & Creative Works

The "Crips" derive their name from "cripples," which in turn derives from the "pimp canes" they carried as their badge and as a weapon with which to cripple anyone who messed with them. the original motivation was self-defense, but that, of course, changed with time. © 2007 by the American Name Society.