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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

The quantitative application of mineral oil and its effect on the flammability of polyester and acetate/polyester FR fabrics used for women's nightgowns

Dehnbostel, Mary Lynne January 1978 (has links)
Two brushed tricot fabrics, a 100% polyester and an 80% acetate/20% polyester FR, were used to pursue the following objectives: 1) to develop a procedure for uniformly applying a known amount of mineral oil to the fabric specimens; 2) to develop a procedure for handling and conditioning the specimens which would maintain the uniformity of the treatment; 3) to determine whether the calculated amount of oil add-on could be verified by extraction; and 4) to determine the effects of mineral oil on fabric flammability before and after laundering in hard water with an alkali built soap. Major findings of the research included the following: 1) an oil-solvent system was selected for applying the oil to the fabric specimens; 2) a system to reduce the migration of oil on the treated specimens was developed; 3) mineral oil increased flammability at approximately 25% and above add-on levels; 4) a synergistic effect on fabric flammability between oil and calcium deposits could not be identified; and 5) a reproducible difference was found between oil contents determined by extraction and those determined by weighing after treatment. / Master of Science
62

Attitudes of working and nonworking mothers toward preschool children

Capone, Linda Joy January 1978 (has links)
Maternal attitudes of working and nonworking mothers were investigated. Demographically, the 60 mothers were highly educated, middle class parents who had preschoolers from three to six years of age. Two groups, consisting of 30 working mothers, the other consisting of 30 nonworking mothers, were administered an 85 item questionnaire. The questionnaire measured three attitudes; dominance, possessiveness and ignoring. A two sample t-test was used to analyze the data. No differences were found in maternal attitudes between working and nonworking mothers conce:cning possessiveness, dominance or ignoring. / Master of Science
63

Fault tolerant clocking system

Fan, Tzu-I Jonathan January 1978 (has links)
The distributions of synchronized clock signals to all elements of a computing system is very important. Fletcher's clock patent is a good solution to this problem. The difficulty with implementation is the tremendous number of interconnections among different clock elements. Two methods are proposed to reduce the number of interconnectons without loss of synchronization and fault-tolerant capability. An mth order clock is a circuit consisting of (3f+1) ** (2** (m-1)) (m-1)th order clocks. Fletcher's clock patent is a 0th order clock. Starting with 0th order clocks, an mth order clock circuit can be built systematically. An mth order clock circuit can generate (3f+1)**(2**m) synchronized clock signals with (m + 1) (3f+ 1) ** ( 2**m) interconnections instead of (3f+1) ** (2*2**m) • Its fault-tolerant capability is also considered. Another type of connection is called Iterative Type, which is further classified into Cascaded Type, Scattering Type and 2-dimensional Type. Each type has its own characteristics. / Master of Science
64

Biological regeneration of activated carbon

Atieh, Sabah A. January 1978 (has links)
A bioreactor using a tapered fluidized bed was built, characterized and tested. The test consisted of biologically removing phenol from an artificial wastewater in the absence of activated carbon. The data collected during this fermentation were logged on a PDP 11/40 minicomputer. Variables such as oxygen and carbon dioxide percent by volume evolved, the dissolved oxygen concentration, temperature, pH and volumetric air flow rate were monitored. The rate of phenol disappearance was also determined. This system was then used to study the biological regeneration of activated carbon. The bioregeneration study showed that up to 67% of the activated carbon adsorptive capacity could be recovered. It also proved that the rate of phenol biodegradation was higher in the presence of activated carbon than in its absence. / Master of Science
65

Microcomputer control of a pneumatic blood pump

Hux, Douglas Eugene January 1978 (has links)
A microcomputer based system is described that controls the operation of a dual chamber, diaphragm-type pneumatic blood pump in both open-loop and closed-loop modes. The open-loop mode of operation allows selection of pumping rate and systolic time parameters. The closed-loop mode of operation allows selection of pumping rate and pump output parameters, with the systolic time parameter adjusted automatically to maintain a selected pump output in spite of load changes. Digital display of all pump operating parameters is provided. A description of the device and the control techniques employed, the interface circuitry and software algorithm developed, a calibration and tuning procedure, and closed-loop response curves are included. / Master of Science
66

Taste sensitivity, eating behavior, and body fatness of preschool children

Bertelsen, Cynthia D. January 1978 (has links)
The possible relationship between body fatness and taste sensitivity was studied. Twenty-five preschool children aged 42 to 61 months served as subjects. Heights, weights, arm circumferences, and triceps skinfolds were measured. Taste sensitivity to quinine sulfate and sucrose was assessed with paired-comparison tests. Eating habits and food preferences were examined via questionnaires and two-day food records. Analysis of data was by simple correlations, means, and analysis of variance. There appeared to be a relationship between taste sensitivity and body fatness. Weight-for-height percentiles were positively correlated with sensitivity to quinine sulfate (p < .05 ). There was a negative correlation between quinine sulfate and the Ponderal Index (p < . 05 ). Sensitivity to sucrose was negatively correlated with the Ponderal Index (p < .01). Subjects were distributed into two groups, those sensitive to quinine sulfate (taste threshold ceiling 2.03 X 10⁻⁵ M) and those insensitive to quinine sulfate (taste threshold ceiling non-existant ). There were significant differences between the two groups in terms of body fatness and percent of foods liked. More sensitive tasters liked fewer foods and had less body fat. Diet during infancy was not correlated with either taste sensitivity or body fatness. There was no relationship between the degree of body fatness and the percent of foods liked. These results support the idea of a relationship between taste sensitivity and body fatness. Subjects more sensitive to taste appeared to have less body fat and to be more discriminating in their food choices than those subjects more insensitive to taste. / Master of Science
67

Consistency of judgments of a professional panel and wearers regarding characteristics of selected sleepwear fabrics

Gallagher, Margaret Jane January 1978 (has links)
The purposes of this study were to determine the consistency of subjective ratings among four professional judges and between those judges and wearers of four fabric series nightgowns. The fabrics included: (1) 100% polyester brushed knit; (2) 100% nylon knit; (3) 80/20% acetate-polyester brushed knit and (4} 80/20% acetate-nylon brushed knit. Data were collected from 55 women who each wore and cared for two garments of differing fiber contents and evaluated them on eight performance characteristics. The consumers rated the fabrics on the following characteristics: soil removal, colorfastness, shape retention, appearance, hand, durability and static. An overall rating was obtained by combining data for the above seven factors. The gowns were also evaluated by four professional raters on the above factors. An overall rating was also determined for these judges. Weighted kappa and z scores were used to measure agreement between judge pairs and between each judge and the wearers for the eight factors. The researcher accepted the hypothesis that rater agreement exceed that expected by chance for all judge pairs on all factors except shape retention. However, for one judge-pair the hypothesis of agreement was not accepted for shape retention. The hypothesis of rater agreement was rejected for each of the judges and the wearers on all factors except overall rating. The hypothesis of agreement was accepted for Judge III and the wearers for the overall rating. The consumers were generally more lenient than the professionals in their evaluations of all fabric characteristics except static electricity. The judges were less critical than the wearers in assessing that factor. / Master of Science
68

An airport environmental information system for Virginia

Gladwin, Douglas N. January 1978 (has links)
An airport environmental impact information system was created for the Commonwealth of Virginia. This computer-assisted system provides readily accessible, timely, pertinent, concise, and easily comprehensible information for those who make airport development decisions significantly affecting the quality of the human environment in Virginia. The Airport Environmental Information System {A*E*I*S) contains relevant airport environmental impact assessment information for airport E.I.S considerations regarding noise, water quality, air quality, wetlands, cultural impacts, socioeconomic impacts, threatened and endangered species, ecological impacts, and other areas. Three computer software systems -- the Conversational Monitoring System (CMS), NOISEMAP, and SURFACE II were utilized to store, process, and report the information contained in the A*E*I*S system. Users may request information by individual chapter (e.g. noise), and in aggregate book form. A*E*I*S contains provisions for the continued use and update of the system. / Master of Science
69

Determination of pinion cutter offsets required to produce nonstandard spur gears with equal strength teeth

Green, Ralph N. January 1978 (has links)
Master of Science
70

Optimization of steel frames via penalty functions

Cofer, William F. January 1978 (has links)
The purpose of this study is to develop a computer program to minimize the weight of steel frames using a penalty function technique. The program is developed and several example problems are analyzed. All structures are designed in accordance with the AISC code. One of the problems is also analyzed by the Fully Stressed Design method, and the penalty function solution has less weight, but takes more computer time. The penalty function solution is checked by hand and found to be a reasonable design. In this investigation, the penalty function method is found to be simple to use, reliable, versatile, and fairly economical for small structures. / Master of Science

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