Classical elasticity cannot be used to explain effects related to material microstructures due to its lack of a material length scale parameter. To mitigate this deficiency, higher order elasticity theories have been developed. Two simple higher order theories and their applications are studied in this research. One is a modified couple stress theory and the other is a simplified strain gradient theory, each of which contains only one material length scale parameter in addition to the classical elastic constants. Variational formulations are provided for these two theories by using the principle of minimum total potential energy. In both cases, the governing equations and complete boundary conditions are determined simultaneously for the first time. Also, the displacement form is explicitly derived for each theory for the first time. The modified couple stress theory is applied to solve a simple shear problem, to develop a new Bernoulli-Euler beam model, and to derive the constitutive relations for hexagonal honeycomb structures, while the simplified strain gradient theory is used to solve the pressurized thick-walled cylinder problem. All these models/solutions are obtained for the first time and supplement their counterparts in classical elasticity. Numerical results obtained from the newly developed models and derived solutions and their comparisons with their counterpart results in classical elasticity reveal that the higher order theory based models and solutions have the capacity to account for microstructural effects; their counterparts in classical elasticity do not have the same capability. Nevertheless, the former are shown to recover the latter if the microstructural effects are suppressed or ignored.

This dissertation examines the relative importance of the information effect on corporate takeover in total takeover gains. It develops the measure of information effect based on the residual income valuation model with I/B/E/S analysts' abnormal earnings forecast revisions. Empirical results show that the information effect and the synergy are estimated to be around 4 percent and 22 percent respectively in the 1,372 US samples during 1980- 2006. Furthermore, almost all of the synergy gains disappear as the deal is expected to be failed while the measured information effect remains afterwards. The evidence suggests that the information effect is more evident in the disciplinary (failed & high Tobin's-q for bidders) or acquisitional (small capitalization & high book-to-market ratio for targets) takeovers while the synergy is greater in the successful tender-offer. Overall, the corporate takeover bid generates information gains up to 15 percent of total takeover gains. It also develops a theoretical model on the market for corporate control using the assumption that there exists management slack which does not contribute to shareholder wealth. This model provides explanations to several questions about corporate takeovers, which include the following: Why do managers prefer takeovers to other investment alternatives? When are they likely to occur? What are the sources of takeover gains? Do takeovers create value? Why are stock offers more common? Who gains from such transactions both in the long and short runs? Why do they occur in massive waves? Why is diversification often attractive to bidder managers? How does corporate governance play its role during this process? And why do managers often resist takeovers? The agency model this paper develops is compatible with existing theories on takeovers including neoclassical, inefficient stock market, and the free cash flow approach. Furthermore, it is consistent with most of the empirical evidence available.

Abstract The objective of this thesis is to study the biological effects of larvae of Aedes albopictus induced by ultrasound exposure. Ultrasound is widely used in medical and biological techniques, most of them are cell killing or tumor eliminating by high-intensity ultrasound. In order to analyse the influences of ultrasound biological effects in vivo, the larvae of mosquito, in this research, were exposed to continuous-wave ultrasound. Some preliminary observations were made with 0-day larvae. The oscillation of the trachea in larvae in response to the ultrasound radiation is simulated using Miller¡¦s cylindrical-bubble activation theory. Dimensions of tubes in the respiratory system of larvae were measured by microscope. The resonant frequency of the tracheae were calculated, and its range is about 0.6¡ã1.5 MHz. It was observed that the tracheae in 0-day larvae were ruptured by ultrasound exposure, and the larvae were dead in the duration of growth, some fourth instar larvae failed to mature into pupae. The maximum mosquito larvae mortality was with 1 MHz irradiation, and it¡¦s in good agreement with the resonant frequency calculated in this paper.

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With limited information processing capacity, people often rely on heuristics, or rule of thumb, to make decisions. In most situations, these heuristics are useful, however, it is possible to result in systematic biases. One of the biases is framing effect, which refers to the phenomenon that the framing message significantly affects how decision maker infer meaning and hence understand the situation. When a specific attribute is framed in positive or negative terms and result in different decision outome, the attribute framing effect occurs. Although a large amount of studies on framing effect has been cumulated, related works on debiasing the framing effect is limited. Based on past literatures, this study proposed a comprehensive framework to suggest and investigate the effect of debiasing strategies, which were developed in terms of sources of bias including individual difference, imcomplete external information and insufficient cognitive effort of decision makers. Four experitmts were conducted in this study. First, the subjective knowledge, objective knowledge and need for cognition are considered as the possible moderator of attribute framing effect. The second experiment aimed to understand that whether the completeness of decision problem and amounts of attributes affect the phemenon of attribute framing effect. The debiasing effect of warning and elaboration were examind in the third and fourth experiments respectively. The results suggested that both subjective and objective knowledge as well as participants¡¦ need for cognition did not moderate the attribute framing effect. Specifically, the attribute framing effect is observed in all groups regardless of the individual differences. Second, the attribute framing effect disappeared when subjects were provided with positive and negative messages simultaneously. Third, attribute framing effect occurred for subjects in one attribute, three and five attribute conditions. That is, one attribute is sufficient for the framing effect to be observed. Moreover, there is an inverted U relationship between subjects¡¦ attitude and the amount of negative attributes. The framing effect was weakened but is not eliminated when the participants were provided with warnings. In addition, weak warning can prevent subjects of high level need for cognition from framing effect, whereas strong warning can eliminate subjects¡¦ framing effect successfully for group of low level need for cognition. Finally, elaboration is the most effective debiasing strategy in this study to eliminate the framing effect.

Due to large amount of solid wastes produced each year, thermal treatment in conjunction with the resource utilization has become attractive in the future. Treatment by pyrolysis can recover the gaseous products for fuels and solid residuals, thus it has potential for R&D and market development.

Nowadays, the economic grows fast and changes a lot. Meanwhile, the central city gets bigger and bigger. More and more buildings locate everywhere while people enjoy their modern life. The needs of electricity grow by the way. In order to provide more power, the Power Company has tried very hard to find new resources. However, there is another problem when transferring the power through crowded city. To avoid the geographic limitation, most of the overhead lines have been changed into under ground lines instead. Sooner or later, the under ground cable will become the main power transmission. This thesis focuses on the current rating distribution of Taiwan 161KV line with various PE underground cables that contain one circuit, two circuits, four circuits, and eight circuits. The current rating goes within various pipes. To find the best economic benefit with the lowest investment by rearranging the pipes to reach the most current rating and by matching the current rating from under ground cable with the over head cable is the main goal of this thesis. JCS NO.168 analyzes the set up map for all the pipes. In order to offer the best power supply, to maintain the longest cable life within the acceptable working days, the calculating scripts support to figure out the current rating in shortest time.

We discussed the electronic properties in AlxGa1-xN/GaN heterostructures. There are six different samples of AlxGa1-xN/GaN we prepared for this experiment, three of them are undoped AlxGa1-xN/GaN with different x values which is 0.17, 0.29 and 0.33, respectively. The others are Fe-doped AlxGa1-xN/GaN which the x value is 0.18, 0.19 and 0.21 for each sample. Comparing these two types¡¦ materials¡¦ results, we tried to confirm the impurity¡¦s characteristic in our samples. From the Hall measurement results, carrier concentration of Fe-doped AlxGa1-xN/GaN were pretty lower than undoped AlxGa1-xN/GaN, and the mobility at 4.2 K are almost two times to undoped AlxGa1-xN/GaN. At the same time, we performed Shubnikov-de Hass measurement, and two subbands of the 2DEG were populated on the samples for x value is 0.29 and 0.33. The energy separation for first two subbands is 109meV. We also observed obvious beat pattern in the SdH oscillations due to the spin splitting on the samples and the greatest spin-splitting energy is 5.96meV in our measurement. Furthermore, we observed evident PPC effect on the samples of Fe-doped AlxGa1-xN/GaN, the carrier concentrations increased at least 23% after illumination. Meanwhile the samples of undoped AlxGa1-xN/GaN can just produce 10.7% increment at most.

Thesis (M.S.E.C.E.)--University of Delaware, 2009. / Principal faculty advisors: Ian Appelbaum and James Kolodzey, Dept. of Electrical & Computer Engineering. Includes bibliographical references.

Thesis (Ph.D.)--University of Central Florida, 2009. / Adviser: Michael N. Leuenberger. Includes bibliographical references (p. 104-115).