In this thesis we present new results for the makespan and the flowtime in a flow shop without intermediate storage between machines. We consider m machines and n jobs with random processing times. Since there is no intermediate storage between machines, a job which has finished processing at one machine may have to stay at that machine until the next machine is free. This phenomenon is known as blocking. Our goal is to select the optimal schedule; in our case, the schedule which in some sense minimizes the makespan or the flowtime. Makespan is the total time required to process a set of jobs and flowtime is sum of all the times at which jobs are completed. Our results require various stochastic orderings on the processing time distributions. Some of these orderings minimize the expected flowtime or expected makespan, and some stochastically minimize the makespan. The stochastic minimization results are much stronger. The optimum sequence in these cases not only minimize the expected makespan, but also maximize the probability of completing a set of jobs by time t for any t. Our last result resolves the conjecture of Pinedo (1982a) that in a stochastic flow shop with m machines, n-2 deterministic jobs with unit processing time, and two stochastic jobs each with mean one, the sequence which minimizes the expected makespan has one of the stochastic jobs first and the other last. We prove that Pinedo's conjecture is almost true. We prove that either the sequence suggested by Pinedo or a sequence in which the stochastic jobs are adjacent at one end of the sequence minimizes the expected makespan. Our result does not require the stochastic jobs to have an expected value of one. Furthermore, we show that our result cannot be improved in the sense that in some cases one sequence is strictly optimal and in other cases the other is strictly optimal. / Master of Science

The present study attempted to validate modified versions of laboratory measures of behavioral impairment from alcohol for use in the field. A total of 195 students at various BAC levels, participated during two outdoor university-sponsored events. In addition to taking nonbehavioral measures of impairment, each subject was asked to perform and evaluate a reaction time task, balance test, and give a verbal index of impairment. The actual BAC of each subject was determined using a breath-alcohol testing machine. The results indicated that self-reported measures of impairment were the best predictors of BAC. Of the behavioral measures, reaction time and body balance performance accounted for the highest portion of the variance in predicting BAC. Subjects reported that actual BAC feedback would most likely result in behavior change, followed by performance on the progressive body balance and reaction time tasks. It was noted, however, that as BAC increased, poor test performance was less likely to result in behavior change. The need for continued research into behavioral measures of alcohol impairment are discussed as a means of promoting third-party intervention and"socially responsible drinking". / Master of Science

A method was investigated to synthesize diamonds at atmospheric pressure without the use of diamond seed crystals. The method was first proposed by Burton in 1905 and appears to have been lost in the literature. The procedure is based on Ostwald's principle of the formation of metastable, intermediate crystals en route to a more-stable final product. Carbon was dissolved in a lead-calcium alloy and was later precipitated out of the melt by the removal of calcium with steam. The calcium was used to increase the solubility of carbon in lead. Reaction temperatures between 775 K and 1025 K were used. The resulting precipitate, analyzed by both chemical and physical means, was found to be well-crystallized graphite. No diamond formation was found to occur. / Master of Science

Ed. D.

No description available.

« Quelle est la pertinence des jugements portés par le discours critique sur la photographie? C'est à cette question que nous avons cherché à répondre en prenant comme objet d'étude le discours critique traitant de la photographie qui a été produit entre 1970 et 1980 au Québec. Et, pour ce faire, notre démarche a été la suivante. Une fois apportés des précisions d'ordre méthodologique sur le cadre de notre étude, le corpus sur lequel elle porte et l'orientation de notre analyse, notre premier chapitre est consacré à la présentation des trois principales tendances que l'on rencontre au sein du discours critique au cours de cette période (soit, une première tendance effectuant une appréciation des oeuvres par le biais de l'artiste, une deuxième, et de loin la plus importante, basant ses jugements sur ce qui serait spécifique à la photographie et une troisième approche faisant une appréciation plus "sociale" de la production photographique) en ayant soin de faire ressortir les points essentiels qui caractérisent chacune d'entre elles. Comme la meilleure façon d'évaluer ce que ces différentes tendances mettent de l'avant est de vérifier la pertinence des principales caractéristiques qui sont ressorties lors de leur présentation, et ce, en les situant par rapport au milieu artistique où elles sont opérantes, le deuxième chapitre fait appel, d'abord, aux recherches de la sociologue américaine Barbara Rosenblum sur les contraintes affectant les photographes selon les conditions de production où ils se trouvent. En les situant dans le contexte québécois, elles nous permettent de voir comment fonctionne le système de diffusion artistique et à quels impératifs sont soumis les photographes y oeuvrant. Puis, dans un deuxième temps, pour mieux comprendre pourquoi il en est ainsi et mieux en saisir les conséquences sur le discours, nous utilisons les travaux du sociologue français Pierre Bourdieu portant sur le processus d'autonomisation du champs artistique. Quant aux arguments utilisés par le discours qui n'ont pas été abordés au cours de cette seconde partie, comme ils font échos aux théories de certains auteurs très importants dans la littérature photographique, le troisième chapitre vérifie la teneur de ce qu'ils proposent en faisant référence, entre autres, aux idées de Walter Benjamin sur la photographie, et en particulier à ce fameux passage de la photographie en tant qu'art à l'art en tant que photographie, ainsi qu'à celles de Roland Barthes concernant la nature du médium photographique. Ce n'est donc qu'à la fin de ce chapitre, après avoir fait le tour de tous ces critères ou notions sur lesquels se basent les différentes tendances du discours critique, qu'il est possible de vraiment évaluer leur contenu respectif. Ainsi nous montrons que, mis à part les quelques représentants de la troisième tendance, les autres ne font tout simplement que refléter l'image ou le fonctionnement du système artistique et par conséquent contribuent toujours davantage à le renforcer, à faire paraître l'état actuel des choses, et les rapports sociaux qui s'y inscrivent, comme l'état naturel des choses. Ce qui nous amène à conclure que pour exercer un rôle qui soit "critique", et non continuer à n'être qu'un simple intermédiaire ou entremetteur entre les intervenants de la scène artistique, le discours doit nécessairement repenser de fond en comble son appareillage conceptuel et à indiquer les premiers jalons, du moins les conditions nécessaires, à un discours désirant remplir une fonction véritablement "critique". Mais sans pour autant prétendre par là avoir trouvé la solution. Car, le domaine artistique étant, comme tout le champ culturel, le lieu et l'enjeu de luttes sociales, il ne peut y avoir de "Solution" ou de "Vérité". Il n'y aura toujours que des choix, que des discours qui s'affrontent. »--Pages préliminaires

The creep and creep recovery behavior of a random fiber composite (SMC-R50) at elevated temperature and constant humidity were investigated experimentally and theoretically. The short time creep response for four constant stress levels at each of four selected temperature levels was experimentally determined. It was found that repeatable results can be obtained by applying a mechanical conditioning prior to each creep and creep recovery test. Creep data were modelled using the Findley equation which contains three parameters, ε_O (the instantaneous creep response), m (the amplitude of transient creep), and n (the time exponent). It was found that the time exponent is a function of time but approaches to an asymptotic value when the duration of creep is long. Thus, at a constant temperature level, one long-time creep test and four short-time creep tests were conducted. The long-time creep results were used to determine the proper time exponent n. The short time creep data for constant load were used to determine the Findley parameters ε_O and m. It was found that the Findley equation represented the creep results very accurately. Based on the short-time creep results, the Findley equation was used to predict the long time creep response and the creep response due to multiple step loadings. Five long time creep experiments were conducted. Four of them were 10,000 minutes long and were conducted at the same stress level (6,510 psi) but different temperature levels. The fifth creep experiment was conducted at 5,425 psi and 185°F over a three week period. Three multiple step creep experiments were conducted. These tests were of different load steps and durations. In all cases, it was found that the Findley equation predicted both long time creep response and multiple step creep response very accurately. Since repeatable results were obtained from conditioned specimens, the test results were compared to experimental data obtained from unconditioned specimens. It was found that experimental results of the conditioned specimens fell within the scatter band of the data for the unconditioned specimens. A free energy based failure criterion (proposed by Reiner and Weisenberg) was coupled with the Findley equation to predict the creep rupture time of SMC-R50. It was found that the critical free energy at the time of failure is temperature dependent. For a constant temperature, the critical free energy required for rupture is essentially a constant. It is also concluded that, for limited data, the Reiner-Weisenberg failure criterion provj.dl!S overall good prediction of the time to failure for SMC-R50. / Ph. D.

Reactions of 4-chloro-2,6-dimethoxypyrimidine (1) with enolates of acetone, pinacolone, diisopropyl ketone, and ethyl phenylacetate generated by means of potassium amide in 1 liquid ammonia were found to proceed by the S<sub>RN>1 mechanism upon photostimulation with near-UV light to give good yields of substitution products resulting from displacement of chloride ion. Both photostimulated and dark reactions of 4-chloro-2,6-dimethoxypyrimidine (1) with the carbanions of acetonitrile and propionitrile proceed exclusively by an ionic mechanism in liquid ammonia or THF to give a mixture of monosubstitution products resulting from displacement of chloride or the 6-methoxy substituent. With the acetonitrile carbanion the product resulting from displacement of methoxide was the major substitution product, while reaction of 1 with propionitrile carbanion afforded a preponderance of the product resulting from chloride displacement. Photostimulated reaction of 2-chlorothiazole (2) with the potassium enolate of pinacolone proceeds by a radical-chain mechanism to give the substitution product resulting from chloride displacement. However, when 2 is allowed to react with pinacolone enolate in the dark a completely unexpected product is formed. Under these conditions, the tertiary alcohol, 2-(2-chlorothiazol-4-yl)-3,3-dimethyl-2-hydroxybutane, was formed in which the pinacolone unit had been incorporated in an aldol fashion at the 4-position of 2. Both photostimulated and dark reactions of 2 with the enolate of diisopropyl ketone produced a similar carbinol, 3-(2-chlorothiazol-4-yl)-2,4-dimethyl-3-hydroxypentane, in good yields. Treatment of 2 with potassium amide in liquid ammonia or LDA in THF followed by addition of benzophenone afforded 2-chloro-4-(diphenylhydroxymethyl) thiazole in excellent yield. Trapping experiments with deuterium oxide and iodomethane provide evidence that such aldol-type reactions take place via initial metalation of 2 at position-4, followed by reaction of the resulting carbanion with the appropriate electrophile. This is the first example of direct metalation occurring at the 4-position of a thiazole derivative. / Ph. D.

The objective was to quantify sublethal effects of two insecticides on the common damsel bug, a major predator in alfalfa. Groups of 2-day-old adult nabids were exposed for 12 h to filter paper treated with LC₅ or LC₄₅ carbofuran, or LC₅ or LC₂₅ methidathion. Males that survived the 4-day acute mortality period lived only 60 percent as long as control males, with low and high concentrations of insecticides producing similar decreases in longevity. More females who survived acute exposure to methidathion were missing portions of appendages at the time of death than in the controls. Although larger pronotal width was related to increased female longevity, to increased egg production, and to increased progeny production, exposure to insecticide had no consistently positive or negative effect. Pretreatment refrigeration affected neither postexposure longevity nor total eggs laid by females. Second instar nabids were exposed for 12 h on filter paper treated with LC₁₅ or LC₃₅ carbofuran, or LC₀ or LC₅ methidathion. Female nymphs which survived exposure to LC₃₅ carbofuran reached the 3rd instar more quickly than control nymphs, whereas methidathion tended to slow development to the 3rd instar. Neither insecticide significantly affected the duration of the 3rd-5th instars. While carbofuran reduced the longevity of adults compared to controls, methidathion only reduced the longevity of the LC₀ group compared to the LC₅ group. Although LC₁₅ carbofuran increased egg production per day alive, carbofuran did not affect total egg production. In laboratory studies male nabids were observed dispersing mistlike droplets (probably pheromone) by rapid movement of a hind leg, or by flicking, a term proposed here. Exposure to carbofuran or methidathion appeared to decrease the frequency of flicking in surviving nabids; however, the decreases were not always significant. Oviposition rates of control females averaged 3-4 eggs/female/d for adults from field-collected nymphs and 6 eggs/female/d for adults from insectary-reared nymphs with peaks around 18-22 d after the final molt. A tachinid, Leucostoma simplex (Fallen), was the most common nabid parasite reared (parasitization rates of up to 40%), while the braconid, Wesmaelia pendula Foerster, parasitized 0-4% of R. americoferus. / Ph. D.

For years, performance appraisal has posed serious problems for those in personnel-related fields; yet, most personnel professionals are unwilling to abandon the practice of formally evaluating job performance. Given this reluctance to discard performance appraisal, many organizations are faced with the task of choosing appraisal systems compatible with their idiosyncracies. This paper presents a model for use in the development of appraisal systems. The model proposes that the effectiveness of a given appraisal system can be predicted from employee attitudes toward parameters of this system, job analysis information, and characteristics of supervisors within the organization. This proposal was tested using job analysis information and attitude data from employees of the Geological Survey of the U.S. Department of the Interior. The appraisal system evaluated, Work Planning and Progress Review (WP&PR), was based upon goal-setting principles. Four studies explored the relationships described above. Study 1 examined the relationships between the quality of standards generated in WP&PR, attitudes toward parameters of this system, and the objectivity with which jobs could be measured. Study 2 questioned whether or not attitudes toward appraisal were the result of the existing appraisal system's effectiveness. Study 3 explored the relationship between attitudes toward appraisal and supervisory style as measured by the Leader Behavior Description Questionnaire (LBDQ), and Study 4 examined the relationship between supervisory style and the quality of performance standards generated in WP&PR. The model for selecting appraisal parameters was only partially supported by the data. Attitudes toward WP&PR were not significantly related to standards' quality or job objectivity. Job objectivity was, however, predictive of the quality of performance standards. change was unrelated to standards' In addition, attitude quality. Supervisory style was found to be related to attitudes toward an immediate supervisor as the source of appraisal; however, it was not related to standards' quality. Exploratory analyses using self-report measures of system effectiveness resulted in greater support of the model. Problems with criteria for measuring appraisal effectiveness and directions for future research / Doctor of Philosophy