An experimental method of indirectly measuring the potential difference across a single mercury-electrolyte interface is suggested. By choosing a model for the moving electrolyte-mercury-electrolyte system, the maximum output voltage (which is mathematically the potential difference across a single interface) is obtained when the back end of the moving mercury drop becomes a hemisphere and the front end becomes a flat circular disc. It has been shown that the U-effect II and the U-effect III are essentially the manifestations of the same effect namely, that the output voltage is due to the distortion of the surface areas of the two ends of the moving mercury drop while the number of dipoles across each interface remains fixed. The output voltage has been found to be dependent on the velocity and the acceleration of the mercury drop and not on the relative displacement of this drop with respect to the capillary wall. The dependence of the output voltage on the acceleration of the mercury drop is opposite to that of the velocity. / Ph. D.

The effect of surface roughness and sliding speed on the wear mode of low density polyethylene was studied with multipass experiments at the high sliding speeds by the use of a pin-on-disk wear machine. Surface roughness was found to be the major parameter in determining the wear mode of the polymer at two different speeds of sliding. The wear mode was shown to be abrasive on the rough surfaces and adhesive on the smooth surfaces. The high wear rates occurring on the rough surfaces was related to the production of the large amounts of loose debris. The effect of speed was found to be an increase in the temperature on the smooth surfaces. This temperature rise was used to explain the increasing wear rate and the decreasing coefficient of friction. No effect of speed was detected for sliding on the rough surfaces, where the frictional energy was dissipated by the formation of loose debris particles. / Master of Science

Three nonparametric control chart procedures are developed. The procedures are designed to detect any shift in the median of a sequence of observations from a specified control value. The first two procedures require that groups of g ≥ 1 observations be made sequentially on the output of the process. Then the Wilcoxon signed-ranks of the observations are computed within each group separately. The Wilcoxon signed-rank statistic SR_ig for the i^th group is computed as the sum of the signed ranks of the th g observations in the i^th group. One of the two procedures employs a cumulative sum control chart-type stopping rule and it signals indicating a shift in the median of the process at the first n for which Σ_i=1ⁿ (SR_ig - k) - min_0≤m≤n Σ_i=1^m (SR_ig - k) ≥ h, where k ≥ 0 and h > 0 are parameters of the procedures, and where Σ<sub>i=1⁰ ≡ 0. The other procedure employs a linear barrier-type stopping rule and it signals at the first n for which Σ_i=1ⁿ (SR_ig & (-a, a), where a > 0 is a parameter of the procedure. Based on the fact that { Σ_i=1ⁿ (SR_ig ; n = 1, 2, ...} forms a discrete time Markov chain, a method for determining the exact properties (average run lengths) of the procedures was developed. The third procedure is proposed for situations where single observations, rather than grouped observations, are made on the output of the process. The procedure requires that an integer M > 1 be fixed apriori and the rank of an observation be computed only with respect to the preceding (M-1) observations. The procedure employs the sum of the signed ranks as a test statistic and a cumulative sum control chart-type stopping rule. It was not possible to determine the exact properties of the procedure through a Markov chain approach. All the proposed procedures are simple to apply in practice since they require little effort in computing the ranks of the observations. Their application does not require that the distribution or the variance of the observations be known. Several comparisons of the proposed procedures were made with other parametric control chart procedures. For normal observations and when a small shift in the mean is considered, there is indication that the proposed procedures perform nearly as good as the parametric procedures. For double exponential observations, some of the proposed nonparametric procedures perform better than the parametric procedures when a small shift in the mean is considered. / Ph. D.

This thesis takes a holistic approach to the development of a building system that responds to the socio-economic, cultural and climatic parameters of urban Iran. The scheme developed is a system of precast (prefabricated) concrete panels that are connected to prefabricated wet core modules, abbreviated "pancore.” Specifically, pancore meets the needs of a rapidly emerging nuclear middle-class family structure, which is concentrated in the urban centers of Iran. Up to the present, the limitations of time and lack of skilled labor in Iran have hindered attempts to provide adequate housing on a mass scale. Now that the pattern of family living has been undergoing change, there is an ever-increasing demand for a different style of urban housing; that is, individual apartment-type dwelling units on a large scale. The proposed scheme not only responds to the above-mentioned criteria, but also surmounts the dependency on skilled labor, since major building components can be produced in the factory. The design process has emphasized the application of the systems approach, both at the micro and macro levels of analysis. Matrices have been developed to evaluate and optimize the design concepts. The optimization and trading off of the design ideas have been uniquely made during the early design development, hence incorporating systems ideas in the building design. The proposed scheme is a result of the application of a holistic approach to architectural systems design. Criteria such as user needs, environmental parameters, and traditional design procedures have been utilized to formulate the design goals. / Master of Architecture

Includes bibliographies and indexes / xvi, 832 p. : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library.

Master of Science