This thesis studies three asset allocation strategies under a defined-contribution pension plan: Buy-and-hold (BH), constant mix (CM), and time-invariant portfolio protection (TIPP). First in this paper, the actuarial assumptions follow Frees et al (1998), as well as Chang and Lin (1999): the age of the beneficiaries is between 25 to 65 and follows the uniform distribution. As to the investment environment, the portfolio includes a risk-free asset, certificate deposit (CD), and a risky asset--the stock. The interest rate of CD is fixed and the return of stock varies according to 14 scenarios. Then the concept of an open-ended fund is applied to compute the NAV (Net Asset Value) of three strategies for each month and a model of defined-contribution pension funds was developed. Moreover, this thesis also discussed the relationship between the trends of the stock and the changes of stock weights, as well as the terminal wealth of pension fund and the income-replacement ratio under each asset allocation strategy. The characteristics and timing of each strategy can be investigated clearly. Finally, the input parameters derived from the data of historical stock market in Taiwan is used to implement Monte Carlo simulation so that the study of the performance of asset allocation strategies can go more close to reality. The endeavor and results of this thesis will be a useful reference to facilitate both the government and private sector to manage the pension fund.

To establish the pension system is to ensure the life of old men. To compare the other pension systems of main countries, the old-aged economics security should adopt three-pillar system in Taiwan. This thesis puts emphasis on the empirical study of the importance of Taiwan pension fund asset allocation and attempts to develop a proper process of asset allocation decision as the reference of the pension fund sponsors when they are dealing with this task. The process of asset allocation decision could be divided into two parts: forming the efficient frontier and selecting the optimal asset allocation. This research suggests the readers to use quadratic programming techniques, which is introduced by Markowitz in 1956, to calculate the efficient frontier. With the changes in the financial situation and the coming of new information, pension fund sponsors should re-perform the process of asset allocation decision periodically to obtain the updated optimal asset allocation. The result of putting restrictions on the ratio of investment items is that the limited portfolio will reduce the utility and return relatively. As for raising the ratio of current assets, the standard doesn¡¦t increase obviously. To impress that pension fund should be in accordance with its need and object to keep appropriate current assets. Furthermore, pension fund sponsors should raise the weight of stocks and bonds to improve the performance. Pension fund sponsors who entrust risky assets to the professional institutions to manage will enhance the performance of investing, but we can¡¦t obtain the data of risk. In the future, the performance should be measured continually and join the risk to analyze.

Thesis (M.B.A.)--Naval Postgraduate School, June 2004. / Thesis advisor(s): Richard Doyle, Ira Lewis. Includes bibliographical references (p. 77-82). Also available online.

The United States Department of Defense has introduced two new GPS civilian signals on its “Link 2” (L2) and “Link 5” (L5) center frequencies. The first of these new civilian signals to reach full operational capability in the GPS constellation will be the L2 C signal. The L2 C signal boasts new signal structure features aimed at better tracking performance in comparison to the legacy L1 C/A signal. Amongst these are two new chip-by-chip interleaved spreading code sequences, Civilian Moderate (CM) and Civilian Long (CL), and a new, higher resolution navigation message, CNAV. The two new C codes are longer than the legacy C/A code and feature a data less pilot signal (CL) for improved tracking performance in weak signal environments. This work investigates L2 C acquisition and tracking considerations and implements algorithms for acquiring and tracking the signal in a software-defined receiver developed in MATLAB. The Emergent MATLAB L2 C (EMAL2) receiver was developed for the purpose of GPS signal simulator testing. This software-defined receiver differs from legacy receivers containing application specific integrated circuits (ASICs) in that all of EMAL2’s digital signal processing is done in software able to run on a general purpose processor. This approach offers greater flexibility and ease in configuration over ASICs for tracking a number of different types of signal structures in the receiver. The EMAL2 receiver’s design and implementation is described here-in. Initial testing of the EMAL2 receiver was conducted with live-sky signal data captured by antennas and front-ends at the University of Texas Radionavigation Laboratory (UT RNL). The data was processed by the GRID receiver (also at the UT RNL) to provide EMAL2 baseline received signal characteristics. / text

The design and development of a software defined radio (SDR) receiver prototype has been completed. The goal is to replace the existing automatic identification system (AIS) manufactured by Vesper Marine with a software driven system that reduces costs and provides a high degree of reconfigurability. One of the key concepts of the SDR is the consideration of directly digitizing the radio frequency (RF) signal using subsampling. This idea arises from the ambition to implement an analog-to-digital converter (ADC) as close to the antenna interface as practically possible. Thus, majority of the RF processing is encapsulated within in the digital domain. Evaluation of a frequency planning strategy that utilizes a combination of subsampling and oversampling will illustrate how the maritime bandwidth is aliased to a lower frequency. An analog front-end (AFE) board was constructed to implement the frequency planning strategy so that the digitized bandwidth can be streamed into a field programmable gate array (FPGA) for real-time processing. Research is shown on digital front-end (DFE) techniques that condition the digitized maritime signal for baseband processing. The process of a digital down converter (DDC) is conducted by an FPGA, which acquired the in-phase and quadrature signals. By implementing a digital signal processor (DSP) for baseband processing, demodulation on an AIS test signal is evaluated. The SDR prototype achieved a receiver sensitivity of -113dBm, outperforming the required sensitivity of -107dBm specified in the International Electrotechnical Commission (IEC) 62287-1 standard for AIS applications [1].

Dramatic changes in medical science and a general improvement in living standards has led to significant reduction in the morality rate of certain age groups in South Africa. As a result the average age at which people are likely to die increased significantly in the 2oth century. The implications of this has not only to increase the number of people who survive to retirement age, but it has also seen larger numbers of people live for much longer periods in retirement. Opposite to the above, is the HIVIAids pandemic, which will increase the mortality rates of individuals at a younger age and undoubtedly affect pension plans and the costs thereof. The effect of all these changes have been the ultimate cost of providing a given pension benefit. At first the paper examines the trend in retirement saving away from Defined Benefit (DB) towards Define Contribution (DC) funds. It looks at the reasons why this shift has occurred in South Africa, and provided confirmation of the retirement savings plans away from DB structures and towards DC type of plans in South Africa. Secondly the paper briefly looks at the operation of DC plans in South Africa. The potential consequences of the shift are then reviewed in the context of roleplayers in the retirement savings decision and personal involvement in retirement planning process. Upon completion of the literature study, a model was developed in which data from DC funds were used to make projections regarding the sufficiency and adequacy of funding within DC funds. This study has proved that the shift from DB to DC funds had an enormous impact on provision for retirement. It was found that a significant part of the population will not be independent at retirement and therefore might potentially became a responsibility of the state. The paper suggests that the level of personal involvement in the retirement savings decision may be a critical factor in determining the propensity of an individual to save for retirement. As a result research is proposed to consider the importance of the three elements in the involvement of the individual in the retirement savings decision: the perceived ownership of retirement savings, the awareness of the need to save for retirement and the understanding of how to save for retirement. / Thesis (M.B.A.)--North-West University, Potchefstroom Campus, 2004.

Adaptive modulation has been actively researched as a means to increase spectral efficiency of wireless communications systems. In general, analytic closed form models have been derived for the performance of the communications system as a function of the control parameters. However, in systems where general error correction coding is employed, it may be difficult to derive closed form performance functions of the communications systems. In addition, in closed form optimization, real time adaptation is not possible. Systems designed with deterministic state optimization are developed offline for a certain set of parameters and hardwired into mobile devices. In this thesis we present stochastic learning algorithms for adaptive modulation design. The algorithms presented allow for adaptive modulation system design in-dependent of error correction coding and modulation constellation requirements. In real time, the performance of the system is measured and stochastic approximation techniques are used to learn the optimal transmission parameters of the system. The technique is applied to Software Defined Radio (SDR) platforms, an emerging wireless technology which is currently being researched as a means of designing intelligent communications devices. The fundamental property that sets SDR apart from traditional radios is that the communications parameters are controlled in software, allowing for real-time control of physical layer communications. Our treatment begins by modeling the time evolution of the adaptive modulation process as a general state space Markov chain. We show the existence and uniqueness of the invariant measure and model performance functions as expectations with respect to the invariant measure. We consider constrained and unconstrained throughput optimization. We show that the cost functions considered are convex. Next we present stochastic approximation algorithms that are used to estimate the gradient of the cost function given only noisy estimates. We conclude by presenting simulation results obtained by the presented method. The learning based method is able to achieve the maximum throughput as dictated by exhaustive Monte Carlo simulation of the communications system, which provide an upper bound on performance. In addition, the learning algorithm is able to optimize communications under various error correction schemes. The tracking abilities of the algorithm are also demonstrated. We see that the proposed method is able to track optimal throughput settings as constraints are changed in time.

Dramatic changes in medical science and a general improvement in living standards has led to significant reduction in the morality rate of certain age groups in South Africa. As a result the average age at which people are likely to die increased significantly in the 2oth century. The implications of this has not only to increase the number of people who survive to retirement age, but it has also seen larger numbers of people live for much longer periods in retirement. Opposite to the above, is the HIVIAids pandemic, which will increase the mortality rates of individuals at a younger age and undoubtedly affect pension plans and the costs thereof. The effect of all these changes have been the ultimate cost of providing a given pension benefit. At first the paper examines the trend in retirement saving away from Defined Benefit (DB) towards Define Contribution (DC) funds. It looks at the reasons why this shift has occurred in South Africa, and provided confirmation of the retirement savings plans away from DB structures and towards DC type of plans in South Africa. Secondly the paper briefly looks at the operation of DC plans in South Africa. The potential consequences of the shift are then reviewed in the context of roleplayers in the retirement savings decision and personal involvement in retirement planning process. Upon completion of the literature study, a model was developed in which data from DC funds were used to make projections regarding the sufficiency and adequacy of funding within DC funds. This study has proved that the shift from DB to DC funds had an enormous impact on provision for retirement. It was found that a significant part of the population will not be independent at retirement and therefore might potentially became a responsibility of the state. The paper suggests that the level of personal involvement in the retirement savings decision may be a critical factor in determining the propensity of an individual to save for retirement. As a result research is proposed to consider the importance of the three elements in the involvement of the individual in the retirement savings decision: the perceived ownership of retirement savings, the awareness of the need to save for retirement and the understanding of how to save for retirement. / Thesis (M.B.A.)--North-West University, Potchefstroom Campus, 2004.

Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 63-67).

Software-Defined Networking (SDN) has become increasing prevalent in both the academic and industrial communities. A new class of system built on SDNs, which we refer to as SDN-Enabled, provide programmatic interfaces between the SDN controller and the larger distributed system. Existing tools for SDN verification and analysis are insufficiently expressive to capture this composition of a network and a larger distributed system. Generic verification systems are an infeasible solution, due to their monolithic approach to modeling and rapid state-space explosion. In this thesis we present a new compositional approach to system modeling and verification that is particularly appropriate for SDN-Enabled systems. Compositional models may have sub-components (such as switches and end-hosts) modified, added, or removed with only minimal, isolated changes. Furthermore, invariants may be defined over the composed system that restrict its behavior, allowing assumptions to be added or removed and for components to be abstracted away into the service guarantee that they provide (such as guaranteed packet arrival). Finally, compositional modeling can minimize the size of the state space to be verified by taking advantage of known model structure. We also present the Verificare platform, a tool chain for building compositional models in our modeling language and automatically compiling them to multiple off-the-shelf verification tools. The compiler outputs a minimal, calculus-oblivious formalism, which is accessed by plugins via a translation API. This enables a wide variety of requirements to be verified. As new tools become available, the translator can easily be extended with plugins to support them.