International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / In this paper, we present the recent results of theoretical development and software implementation of a complete collection of high-performance image reconstruction algorithms designed for high-resolution imaging for various data acquisition configurations.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / In this paper, the research prototype of a high-performance GPR imaging system is presented. The system is equipped with the capability of synthetic-aperture scan, stepfrequency FMCW illumination, and high-resolution tomographic image reconstruction.

We consider the smoothing problem for a class of conditionally linear Gaussian state-space (CLGSS) models, referred to as mixed linear/nonlinear models. In contrast to the better studied hierarchical CLGSS models, these allow for an intricate cross dependence between the linear and the nonlinear parts of the state vector. We derive a Rao-Blackwellized particle smoother (RBPS) for this model class by exploiting its tractable substructure. The smoother is of the forward filtering/backward simulation type. A key feature of the proposed method is that, unlike existing RBPS for this model class, the linear part of the state vector is marginalized out in both the forward direction and in the backward direction. / CNDM / CADICS

The biomechanics and muscle activity of forward and backward slope walking was investigated in humans to gain additional insight into neural control strategies. An adjustable instrumented ramped walkway was constructed and validated. Kinematic, ground reaction force, and muscle activity data were collected from nine subjects walking at three grades (0%, 15%, and 39%) for each of four conditions (forward upslope and downslope and backward upslope and downslope). The changes observed in the data were generally progressive from 0% to 15% to 39% grade. During forward downslope walking the joint moment pattern at the knee changed significantly, power absorption increased, and changes in the muscle activity patterns corresponded directly to changes in joint mechanics. During forward upslope walking, the hip joint moment pattern changed significantly, power generation increased, and changes in the muscle activity pattern were not directly related to changes in the joint moments at all joints. The muscle activity pattern data suggest that modifications to the level walking control strategies were necessary during slope walking. Backward slope walking was used to further explore these findings. Backward upslope and forward downslope kinematics and kinetics were similar, as were those from backward downslope and forward upslope walking. However, power generation increased during upslope walking tasks and power absorption increased during downslope walking tasks, and the changes in muscle firing patterns were more similar for these tasks than for those with similar kinetics. Increased power generation required compensatory muscle activity at adjacent joints that was not directly related to the moments at those joints; increased power absorption did not require such compensatory activity, and muscle activity was directly related to the joint moments. Overall, these data suggest that changes in the control strategy and/or modifications of the level walking control strategy are strongly influenced by the power demands of a task. The characterization of forward and backward slope walking presented here is novel and has important implications for many patient populations; knowledge of the task mechanics may be used to develop or improve physical therapy and rehabilitation exercise programs as well as the design of replacement and/or assistive devices.

This dissertation presents a numerical simulation of three-dimensional flow and heat transfer in a channel with a backward-facing step. Flow was considered to be steady, incompressible, and laminar. The flow medium was treated to be radiatively participating. Governing momentum equations, energy equation, and the radiative equation were solved by a finite volume method. Extensive validation studies were carried out. As part of the validation study, three-dimensional combined convection and radiation in a rectangular channel without a backward-facing step was studied. The SIMPLE algorithm was used to link pressure and velocity fields. The combined convective-radiative heat transfer were studied by varying three parameters, i.e. optical thickness ( H τ =0.1, 0.2, and 0.4) and scattering albedo ( ω=0, 0.25, 0.5, 0.75 and 1). Variation of thermophysical properties with temperature was considered in this study. In this work consideration was given only to cooling. Effects of those radiative parameters on velocity, bulk temperature, and Nusselt number are presented in detail. The fluid with a hot inlet compared to a cold wall was cooled in a relatively short distance from the channel inlet because of the radiation effect. The thermal penetration decreased with a decrease in optical thickness and an increase in scattering albedo. Thermal penetration increased with increasing optical thickness and decreasing scattering albedo. The reattachment length varied with temperature due to variation of thermophysical properties with temperature.

The present work investigates the phenomena of whip and whirl for a rigid rotor contacting at two bearing locations. The idea originated from an anemometer consisting of a rotor with an elastically supported stator undergoing the phenomena of dry friction whip and whirl at the two bushing contacts. To analyze the behavior, a mathematical model similar to the anemometer is developed and analyzed assuming two possible solutions, Mode1 (normal reaction forces in phase at two contacts) and Mode 2 (normal reaction forces out of phase at two contacts). Analytical solutions are only possible for the models with same RCl (Radius to Clearance ratio) at the two rub locations. A simulation model is constructed using the Texas A&M University (TAMU) Turbomachinery Laboratory rotordynamics software suite XLTRC² comprised of Timoshenko beam finite elements to form multiple degrees of freedom rotor and stator models. The nonlinear connections at the rub surface are modeled using Hunt and Crossley‘s contact model with coulomb friction. Dry friction simulations are performed for three separate models depending on the rotor‘s mass disk location with respect to the contact locations. The three models used have (1) Disk at center location (2) Disk at 3/4 location (3) Disk at overhang location. The adequacy of the analytical solution is investigated using the above simulations. Also, cases are explored where the general assumed solution would not solve the mathematical model, e.g. different RCl ratios at the two contacts. Simulations are performed for increasing as well as decreasing running speeds. There is partial agreement between simulation predictions and the analytical solutions for the cases with the mass center at centered and at 3/4 location. First, whirl-to-whip transitions occur at near the combine rotor-stator bounce frequency for both disk at center and disk at 3/4 location. The case with overhang mass disk predicts the two contacts to whip and at different frequencies simultaneously. Neither of the analytical solutions predicts a case where precession occurs at two different frequencies at the two contact points. Predictions for models with different RCl on the Backward Precessional (BP) graph imitate whirling. The BP graph predicts increasing BP frequency with increasing rotor speeds which is a characteristic of whirling, whereas investigation of individual contact velocities suggest that they are slipping at all conditions, one of them slipping more than the other netting a whirling like motion. For the overhang model with different RCl, apart from whipping at different frequency the two contacts also whirl at different frequencies corresponding to the RCl at the respective contacts. Simulations for decreasing rotor speed predict jump down from whirl- to-whip different BP frequency as compared to the jump up from whip-to-whirl for the speed up.

The research of corporate financial distress prediction model is always one of the important topics in financial management; and mostly people do the research and extract sample companies based on the definition for corporate default by Taiwan Economic Journal. However, we think the timing to observe the potential corporate financial distress is extremely vital; the actual benefit will not be good even with high accuracy if relevant counterparties recognize it too late to undertake certain action for mitigating loss. The main purpose of this study is trying to alert potential corporate financial distress as early as possible, and then could contribute some to this topic. This study extracts 34 financial alerted sample companies with share prices plumped by 50% dramatically or alternatively with share prices diminished below their face value while the stock market index rose in 2007. We matched each sample company by another financially healthy company from the same industry, chose 25 financial ratios to be the variables, and running through each year by adopting logistic regression analysis. We put all variables into the regression formula and weeded out insignificant prediction variables one by one by Wald Backward Elimination, and then sieved out relatively meaningful ones. The first conclusion of this study is that we should use quarter as the financial intervals for this type of sample companies. Secondly, we found that in December and September 2007 there were three significant variables, i.e. Return on Equity (ROE), net income, operational profit ratio, inventory and account receivable to equity ratio. Thirdly, there were three significant variables in June 2007, i.e. earning before tax ratio, growth ratio of operational profit and total liability/ total equity.

No description available.

No description available.

The relevance and reliability of annual financial reports as a basis for making decisions about an organisation came in dispute after a series of corporate collapses. Sustainability reports have similarly suffered weaknesses and stakeholders are unable to form a comprehensive picture of an organisation’s performance and its ability to create and sustain value. Integrated reporting incorporates concise and material information from financial statements and the sustainability report and other sources to enable stakeholders to evaluate the organisation’s performance and to make an informed assessment about its ability to create and sustain value. The focus of this study was to investigate the opinion of employees as stakeholders of a South African bank and their perception of the relevance of the elements in an integrated report, if they had to assess the ability of an organisation to sustain value in the future. A literature study was conducted to address the concept of integrated reporting and the integrated report as well as relevant aspects. Based on the literature study, integrated reporting should enable stakeholders to assess the ability of the organisation to create and sustain value over the short-, medium- and long-term. Special attention has been given to the elements to be included in an integrated report as suggested by the IRC SA’s framework and employees as stakeholders of organisations. The latter has been used as basis of the empirical study that was conducted. The empirical study focused on the opinion of employees regarding the relevance of the eight elements in an integrated report as stakeholders of a South African bank and it was conducted by means of a self-completion questionnaire. The internal consistency and reliability of the questionnaire was assessed by calculating Cronbach alpha coefficients and it had acceptable reliability. Frequency distributions, mean values and standard deviations were calculated as well as independent t-tests and Anovas to determine the differences between the means of different groups within the selected demographic variables and the constructs. Furthermore, effect size values (d-values) were used to indicate if there were practical significant differences between any demographical variables regarding the constructs and individual questions. In the final chapter, conclusions were drawn based on the literature and empirical study. It was evident from the empirical study that most of the respondents found the elements to be either moderately or totally relevant to be included in a report, if the ability of an organisation has to be assessed to sustain value in the future. Recommendations were provided on three elements (business model, remuneration policies and analytical commentary) and the report was concluded by recommending possible future research that could be conducted based on this study. / Thesis (MBA)--North-West University, Potchefstroom Campus, 2013