Tübingen, University, Diss., 1998.

Thesis (M. Div.)--Grace Theological Seminary, 1986. / Abstract. Includes bibliographical references (leaves 53-57).

An evolutionary tree represents the relationship among a group of species, DNA or protein sequences, and play fundamental roles in biological lineage research. A high quality tree construction relies heavily on optimal multiple sequence alignment (MSA), which aligns three or more sequence simultaneously to derive the similarity. On the other hand, a good tree can also be used to guide the MSA process. Due to the high computational cost to conduct both the MSA and tree construction, parallel approaches are exploited to utilize the enormous amount of computing power and memory housed in a supercomputer or Linux cluster. In this paper, first of all, a divide and conquer based parallel algorithm is designed and implemented to perform optimal three sequence alignment using reduced memory cost. Secondly, all internal nodes of a phylogenetic tree resulting from a parallel Maximum-likelihood inference software are labeled using the parallel MSA. Such tree node labeling process is carried out from top down and is also parallelized to fully utilize the numerous cores and nodes in a high performance computing facility.

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This thesis provides a methodology for examining forest harvesting operations through simulation. The model is capable of simulating multiple landing, single dump logging configurations. Facility locations, equipment types and numbers, parameters, and functional relationships may be varied so that a wide range of west coast British Columbia logging operations can be represented. The model was written in General Purpose Simulation System V (GPSSV) language. A substantial saving in development cost is realized over a FORTRAN-based simulation. The model allows independent users to make modifications within the program in order to adapt to the particular operating rules and policies of their operations. Model formulation for this thesis is based on an actual west coast logging division. Verification of the model involves a three-stage approach. First, a set of hypotheses and postulates are constructed for the subsystems of the harvesting operation and, secondly, these are empirically tested. Historical data is compared to simulation results in order to confirm that particular subsystems adequately model the real system. Tactical considerations and experimental design regarding model execution are presented. It is shown that antithetic variates can be effectively used to reduce the variance of the mean of a response. An improved truck dispatching routine is developed with the objective of maximizing productivity, subject to the availability of yarding and trucking resources. This policy balances the objectives of minimizing truck travel time, truck delays at landings, and yarding stoppages due to timber "saturated" landings. In comparison with other dispatching policies, productivity can be increased from two to over ten percent. The dispatching algorithm has been programmed for a Hewlett-Packard 9830A desktop computing system. The dispatcher, utilizing radio communications with all of the landings and trucks, can theoretically be supplied with the optimum landing to which a truck should be dispatched. Some other practical applications of the timber harvesting simulation model are discussed. Flexibility in the model, in parameter initialization and the substitution of new relationships, allows the investigation of many features of forest resource planning and machine allocation and scheduling. The determination of equipment requirements for various configurations, the evaluation of new equipment and the comparison of different operating policies can be undertaken with the model. Another benefit derived from the development of the model is an increased understanding of the timber harvesting system which allows the design of better operating policies and greater control within the system. / Forestry, Faculty of / Graduate

A great number of trees and shrubs are at the disposal of the landscape gardener. He has at his command all kinds and types of plants, and by proper selections he can obtain any desired effect. Our native flora, which is rich in variety of material, has been supplemented to a great extent by the additional of many new things of great value. These new things have come from two sources, the hybridizer and from other countries. The hybridizer has given us new horticultural species and numberless new varieties; but the largest increase has come through the introduction of the native flora of other countries.

Governments of developing countries face the dual tasks of increasing agricultural productivity and ensuring sustainability of resources. The government of Ethiopia initiated a major rural development program in Tigray, Ethiopia ten years ago, called SAERT (Sustainable Agricultural and Environmental Rehabilitation), to change the decline in agricultural productivity and reverse local forest degradation. SAERT targets water resource development through the construction of regional public microdams, intended to bring irrigated agriculture to surrounding villages and improve household income. Through SAERT, villagers can choose to plant trees on public microdam sites, protected and monitored by the surrounding villages. Unfortunately, microdams may cause potentially serious side effects to human populations through water-borne illnesses such as malaria and schistosomiasis. This paper examines incentives for villagers in Tigray to plant trees for private use, in both villages with and without access to regional public microdams. In addition, we investigate the importance of health factors on the household decision to plant trees on household and public land. / Master of Science

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