The Onsager heat of transport, Q*, has been measured for water vapour above glycerol-water solutions (75 % to 94.5 % glycerol) over a temperature range of -46 to -32 ℃. For solutions of concentrations 80 % and above, Q* varied from 5.41 kJ mol-1 ± 0.97 to 17.37 kJ mol-1 ± 2.61, consistent with previous results for aniline and n-heptanol. The dissociation of glycerol-water complexes was not rate determining, as was the case for sulfuric acid-water solutions, and therefore the glycerol-water system is a better two component system analog for comparison with the CO2-water system than the sulfuric acid-water system.

Solubility of drugs in non-aqueous systems is very important in understanding the partitioning and transport behavior. The present study was undertaken to evaluate the entropic and enthalpic contribution to activity coefficient of organic compounds (polycyclic aromatic hydrocarbons, aliphatic acids, aliphatic alcohols etc.) in non-aqueous solvents. The activity coefficient can be written as: ln γ₁ = ln γ₁ᶜ + ln γ₁ʳ where superscript "c" and "r" denote entropic (combinatorial) and enthalpic contribution respectively. We selected three solvent systems: benzene, triolein and octanol. The different models considered in this study were Flory-Huggins, Scatchard-Hildebrand, UNIQUAC combinatorial and UNIFAC residual. A combination of Flory-Huggins and Scatchard-Hildebrand which accounts for both the entropic and enthalpic effects gives the best predictions in all the solvents considered.

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Disertacijoje nagrinėjami kelio trasos projektavimo dėsningumai, projektiniai sprendiniai žvyrkelių rekonstrukcijos projektuose ir jų sąsajos su automobilių kelių projektavimo normų nuostatomis. Disertacijos tikslas – pasiūlyti metodus kelio trasos projektinių sprendinių kokybei gerinti. Disertacijoje sprendžiami šie uždaviniai: nustatyti kelio trasos projektinių sprendinių sąsajas su automobilių kelių projektavimo normų nuostatomis, įvertinti esamos kelio trasos geometrinius parametrus numatomuose rekonstruoti žvyrkeliuose, atlikti lyginamuosius avaringumo tyrimus, įvertinti kelio trasos projektinių sprendinių kokybę žvyrkelių rekonstrukcijos projektuose, pateikti rekomendacijas Lietuvos Respublikos automobilių kelių projektavimo normų nuostatoms tobulinti. Disertaciją sudaro įvadas, 5 skyriai, bendrosios išvados ir rekomendacijos bei priedai. / The dissertation studies regularities for the design of road alignment, design solutions in the gravel road reconstruction projects and their links with the require-ments of road design standards. The aim of the dissertation – to suggest methods for improving the quality of design solutions. The following tasks are solved in the dissertation: to determine the links of design solutions of road alignment with the requirements of road design standards, to evaluate geometric parameters of the existing road alignment on the gravel roads to be reconstructed, to carry out comparative investigations of accident rate, to determine the quality of design solutions of road alignment in the gravel road reconstruction projects and to give recommendations for improving the requirements of the road design standards of the Republic of Lithuania. The dissertation consists of introduction, five chapters, general conclusions, recommendations and addenda.

The dissertation studies regularities for the design of road alignment, design solutions in the gravel road reconstruction projects and their links with the requirements of road design standards. The aim of the dissertation – to suggest methods for improving the quality of design solutions. The following tasks are solved in the dissertation: to determine the links of design solutions of road alignment with the requirements of road design standards, to evaluate geometric parameters of the existing road alignment on the gravel roads to be reconstructed, to carry out comparative investigations of accident rate, to determine the quality of design solutions of road alignment in the gravel road reconstruction projects and to give recommendations for improving the requirements of the road design standards of the Republic of Lithuania. The dissertation consists of introduction, five chapters, general conclusions, recommendations and addenda. / Disertacijoje nagrinėjami kelio trasos projektavimo dėsningumai, projektiniai sprendiniai žvyrkelių rekonstrukcijos projektuose ir jų sąsajos su automobilių kelių projektavimo normų nuostatomis. Disertacijos tikslas – pasiūlyti metodus kelio trasos projektinių sprendinių kokybei gerinti. Disertacijoje sprendžiami šie uždaviniai: nustatyti kelio trasos projektinių sprendinių sąsajas su automobilių kelių projektavimo normų nuostatomis, įvertinti esamos kelio trasos geometrinius parametrus numatomuose rekonstruoti žvyrkeliuose, atlikti lyginamuosius avaringumo tyrimus, įvertinti kelio trasos projektinių sprendinių kokybę žvyrkelių rekonstrukcijos projektuose, pateikti rekomendacijas Lietuvos Respublikos automobilių kelių projektavimo normų nuostatoms tobulinti. Disertaciją sudaro įvadas, 5 skyriai, bendrosios išvados ir rekomendacijos bei priedai.

Environmental and safety concerns have prompted an active quest for ―green‖ alternatives to / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2009.

Portfolio selection is an example of decision making under conditions of uncertainty. In the face of an unknown future, fund managers make complex financial choices based on the investors perceptions and preferences towards risk and return. Since the seminal work of Markowitz, many studies have been published using his mean-variance (MV) model as a basis. These mathematical models of investor attitudes and asset return dynamics aid in the portfolio selection process. In this thesis we extend the MV model to include the cardinality constraints which limit the number of assets held in the portfolio and bounds on the proportion of an asset held (if any is held). We present our formulation based on the Markowitz MV model for rebalancing an existing portfolio subject to both fixed and variable transaction cost (the fee associated with trading). We determine and demonstrate the differences that arise in the shape of the trading portfolio and efficient frontiers when subject to non-cardinality and cardinality constrained transaction cost models. We apply our flexible heuristic algorithms of genetic algorithm, tabu search and simulated annealing to both the cardinality constrained and transaction cost models to solve problems using data from seven real world market indices. We show that by incorporating optimization into the generation of valid portfolios leads to good quality solutions in acceptable computational time. We illustrate this on problems from literature as well as on our own larger data sets.

In this dissertation we obtain an e cient hybrid numerical method for the solution of stochastic di erential equations (SDEs). Speci cally, our method chooses between two numerical methods (Euler and Milstein) over a particular discretization interval depending on the value of the simulated Brownian increment driving the stochastic process. This is thus a new1 adaptive method in the numerical analysis of stochastic di erential equation. Mauthner (1998) and Hofmann et al (2000) have developed a general framework for adaptive schemes for the numerical solution to SDEs, [30, 21]. The former presents a Runge-Kutta-type method based on stepsize control while the latter considered a one-step adaptive scheme where the method is also adapted based on step size control. Lamba, Mattingly and Stuart, [28] considered an adaptive Euler scheme based on controlling the drift component of the time-step method. Here we seek to develop a hybrid algorithm that switches between euler and milstein schemes at each time step over the entire discretization interval, depending on the outcome of the simulated Brownian motion increment. The bias of the hybrid scheme as well as its order of convergence is studied. We also do a comparative analysis of the performance of the hybrid scheme relative to the basic numerical schemes of Euler and Milstein. / Mathematical Sciences / M.Sc. (Applied Mathematics)

Chinese left-handed are found to be very few, especially in terms of handwriting. The Chinese educational policy that fully entitles teachers in primary school to change the left-handed students to write with their right-hand, by nudging and even force, is found to be mainly blamed as the main cause. The thesis is to raise the ethical discussion and define this policy as being discriminatory against the left-handed by checking the features, definition and identification of discrimination, and reasons forming and supporting such a discriminatory policy will be taken into the major consideration as the source of discrimination. Therefore, the thesis is to propose solutions to help with the abolishment of the policy and the elimination of the prejudicial attitudes toward the left-handed, especially in terms of writing. The thesis itself, due to the limit of previous research and scientific support, has its own blindness or disadvantage, however, such a work could be helpful with the later discussion.

Approved for public release; distribution is unlimited / This thesis developed a deterministic Markov state model to provide the U.S. Navy Nurse Corps a tool to more accurately forecast recruiting goals and future years force structure. Nurse Corps data was provided by the Nurse Corps Community Manager's office covering fiscal years 1990 to 2003. The probabilities used in the Markov model were derived from the fiscal year data. Transitions used in this model were stay at present grade, move up one grade or exit the system. Backward movement was not allowed and individuals could only move up one grade per year. The model was limited to eleven years and focused primarily on the ranks of O-1 to O-3. O-4's and O-5's that appeared in the data were allowed to flow through the system. Logistic regression was then used to investigate the probability of "staying" in the Nurse Corps to certain career decision points. Nurse Corps cohort data files for fiscal years 90 through 94 were merged for analysis, as was cohort data for fiscal year 96 through 98. Results of the markov model show that the O-1's and O-2's reach a steady state at the eight-year mark while the O-3's reach a steady state at the seventeen-year mark (based on provided data). The steady state values are compared to actual Nurse Corps goals. Results of the logistic regression show that Recalls, Medical Enlisted Commissioning Program and Nurse Candidate Program were all significant at increasing the probability of staying in the Nurse Corps. Males were more likely than females to stay in the Nurse Corps and changes in education levels decreased the probability of staying in the Nurse Corps. / Lieutenant, United States Navy