The purpose of this thesis is not to begin with a premise and follow it through, but to discover through two different projects to what extent architecture can be understood, and to examine those "tools" of architecture that turned inspiration and conception into projects with architectural qualities. / Master of Architecture

Moment end-plate connections are widely used in the metal building industry and portal frame construction. This is due to the advantages of the field-bolted construction and excellent performance of moment end-plate connections. These connections have been studied extensively. Yield-line analysis has been used to predict the strength of the end-plate, and a modified Kennedy method has been used to predict the strength of the bolts. These analysis procedures have proven quite accurate. The major drawback is that the calculations involved in the modified Kennedy method are long and complex. In this study, an alternative and simplified method of design for five configurations of moment end-plate is presented. To determine the connection capacity based on bolt strength, the concept of the number of effective bolts is employed. The connection capacity based on the end-plate strength is calculated by making use of the tee stub analogy. Comparisons are made between the simplified method and the yieldline and modified Kennedy based methods. Also, comparisons are made between the simplified method and a method proposed by Borgsmiller and Murray (1995). Design recommendations are given, and design examples are presented. / Master of Science

This thesis presents a technique for synthesizing weighted four-bar linkages to produce a specified resisting force or torque. Historically, mechanism force synthesis has assumed that output positions must always be associated with prescribed forces. This results in the loss of design parameters. Applications which do not require a specified output position benefit from the design method presented in this thesis. This thesis presents two significant contributions to the field of kinematics. First, it contains a full development and demonstration of the use of integrated force constraints to develop position constraints for linkages. Second, it presents the development and use of inverse-mechanical-advantage sensitivity as an evaluation and design tool. The mathematical derivation of a novel synthesis technique is presented in full detail. Also presented is a complete and robust design method for force-generating linkages that has been implemented in software, tested in hardware design, and adopted by industry. The closed-form-equation-based synthesis technique developed herein provides the designer with a graphical representation of an infinite solution set to the force generation problem. Associated sensitivity, static and dynamic analyses allow the designer to quickly evaluate each solution. / Master of Science

The relationship between coping and adjustment, optimism, and frequency of blood glucose monitoring was examined in 99 adolescents (88 female, 11 male). Participants were between the ages of 12 and 18 with a mean age of 14.8 years. Mean duration of diabetes at the time of participation was 5.3 years. Coping theory using approach and avoidance techniques (Ebata & Moos, 1991) along with Scheier and Carver's (1992) theory of optimism are the basis of the theoretical framework. Regression analysis was used to determine the relationships between coping, adjustment and frequency of blood glucose monitoring. Results indicate that perceived stress to being diabetic was related to lower adjustment and less optimism. Use of approach coping techniques was linked to greater adjustment and optimism. Use of avoidance coping techniques was associated with poorer adjustment. Although avoidance coping may be beneficial in attempting to reduce the tension and anxiety surrounding the day-to-day stressors or chronic hindrances of diabetes, continued use can result in serious health consequences. Duration of the disease, perceived stress, and optimism were all found to be related to frequency of blood glucose monitoring. Blood glucose monitoring is one of several adherence behaviors employed by diabetics to improve their control. Previous research found that tighter control achieved by increasing the frequency of blood glucose monitoring and insulin injections significantly reduces the risk of long-term complications ("Living Well," 1993). / Master of Science

This thesis addresses issues related to the use of an active clamp (ACL) circuit in high-frequency PWM converters with an electrical isolation. Existing design guidelines and design trade-offs for the ACL in forward and flyback converters are reviewed, and specific properties of both circuits that are caused by the ACL are highlighted. Based on the obtained results, a robust single-switch active clamp (SS ACL) for the Weinberg converter is developed and evaluated using the Weinberg converter employed in the Space Station as an example. The ACL in the Weinberg converter provides recovery of the magnetic leakage energy, ZVS for all switches, and minimum voltage stresses on switches. Therefore, it allows a reliable high switching frequency operation without a significant increase of the switching losses. This makes the ACL Weinberg converter a prime candidate for high-voltage, high-power space distribution systems. This thesis also investigates impacts of the ACL on dynamic behavior of all the aforementioned circuits. The investigation led to the discovery of a significant detrimental effect that the ACL can have on dynamic characteristics of the ACL forward converters operated with the ZVS. A new small-signal model that predicts that effect is derived using the state-space averaging, and necessary steps for its elimination are proposed. / Master of Science

The purposes of this study were to develop a chemical precipitation procedure that would treat the sodium bearing waste (SBW) and to determine if polymer addition could condition the resulting sludge. Chemical precipitation parameters such as impeller mixing speed, rate of base addition, amount of added calcium to SBW, and solution precipitation pH were studied to determine the conditions for each parameter to achieve optimal solids removal rates and resistance to filtration. The organic polymers were gauged by their ability to properly condition the sludge by use of capillary suction time (CST) apparatus and wedge zone simulator (WZS). Low impeller mixing speeds cause less excess floc deterioration and lower resistance to filtration. Slower base addition rates increase the overall titration time but improve sludge characteristics. Adding calcium to SBW decreases the specific resistance of the sludge. The best dewatering rates occur when solution precipitation pH is between 8.5 and 9.5. This region provides the best cake solids and removal rates of the dissolved species. WZS and high speed centrifugation provide cakes solids above 20%. Medium to high molecular weight anionic polymers properly condition the SBW sludge. / Master of Science

Swan is a data structure visualization system. Using Swan, a C or C++ program can be annotated to provide multiple views of the data structures used in the program so that they can be better understood by the viewer. Swan allows visualization to be a two-way communication process between the viewer and the program. Several automatic graph layout algorithms are implemented in Swan for layout of various data structures. Automatic layout allows the annotator to concentrate on the logical views of data structures without worrying about their graphical display. Swan serves as a data structure visualization system, a graphical debugging tool, and a platform for experimenting with graph layout algorithms. / Master of Science

The purpose of this study was to demonstrate the efficacy of an exercise (walking) adoption intervention delivered through computer networks using electronic mail. The study involved 65 participants (17 males, 48 females), recruited through electronic bulletin board postings and flyers, who were randomly assigned to one of two conditions. The <i>full</i> treatment involved information, prompting, self-monitoring, goal setting and specific electronically delivered weekly feedback on walking performance. The <i>minimal</i> treatment condition involved all procedures <u>except</u> the specific feedback. During the 10 week program, participants in the full treatment who used the computer based system each week, compared to participants in the minimal treatment, walked more days (x̄=2.15 vs x̄=3.01), more minutes (x̄=76.17 vs x̄=107.73), more fitness minutes (x̄=57.90 vs x̄=88.41), and met ACSM minimum guidelines (frequency and duration) during more weeks (x̄=4.14 vs x̄=6.30). Analyses also showed setting and attaining goals was related to increased walking frequency. Survival analyses showed the full treatment condition particularly reduced and delayed dropouts of participants who were designated as contemplators or preparers (stage of change) at the start of the study. In addition, low enjoyment of walking was related to lower walking frequency and drop-out. In this highly computer-literate sample, computer attitudes were not related to infrequent interaction with the computer-based system. The study demonstrated the potential for using computer networks as a health behavior delivery system and showed the importance of goal setting and specific feedback, but also suggested the need for further tailoring of program offerings based on stage of change and other person characteristics. / Master of Science

For indoor wireless communication systems, RF transceivers need to be placed strategically to achieve optimum communication coverage at the lowest cost. Unfortunately, the coverage region for a transceiver depends heavily on the type of building and on the placement of walls within the building. Traditionally, therefore, transceiver locations have been selected by human experts who rely on experience and heuristics to obtain the optimum (or near-optimum) placement. This thesis describes an interactive software system that can be used to assist in transceiver placement. It is intended to be easy to use by individuals who are not experts at wireless communication system design. After the user has selected transceiver locations within a graphical floor plan, the system interprets the floor plan and uses simple path loss models to estimate coverage regions for each transceiver. These regions are highlighted, enabling the user to assess the total coverage. This thesis describes the methodology used to compute the coverage regions for multifloored buildings. The effect of interference sources on coverage regions has also been analyzed using simple propagation prediction models. The resulting system is expected to be useful in the deployment of indoor wireless systems. / Master of Science

The network home office project design is based upon a systems engineering model in the context of the life cycle. This design allows Lockheed Martin Corporation employees the opportunity to work at home and communicate with the program network at the site office via computer. The network home office provides greater job flexibility for employees while reducing overhead costs for Lockheed Martin. A definition of needs justifies the establishment of this design. Advanced system planning provides detailed requirements for operation, maintenance, and support of the system. A system functional analysis allocates requirements from the system to subsystem components. Life-cycle cost analysis is performed on the system to determine system cost-effectiveness. Detail design requirements define the system, subsystem, and office specifications. Human factors engineering is applied to the system, to ensure high productivity. The system is tested and evaluated for optimal performance. Recommendations for future enhancements are presented. / Master of Science