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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.
131

Politics and Eschatology: Christian, Muslim and Liberal Traditions and Their Visions of Humankind's Future

Loureiro, Roberto V. 2010 December 1900 (has links)
Within the context of contemporary politics, Christian, Muslim and Liberal traditions have been, in many instances, at odds with each other regarding how humankind‘s social political future should be ordered. Such a conflicting condition has been aggravated by the global circulation of democratic ideals, which has significantly disseminated Western liberal values and made those ideals an almost universal desirable social commodity. In support of this argument, one can observe the unprecedented and controversial assumption that liberal democracy has become the ultimate form of political governance. It is in the context of these end-times liberal aspirations, whether self desired or imposed through external pressure, that some competing and conflicting elements are introduced into the political landscape of Christian and Muslim groups. By presenting itself as the universal and final solution for humanity‘s future, liberalism appears to create uneasiness among religious people who, indeed, see its secular and religious-privatizing tendencies as a secular eschatological competitor. Despite this perceived end-times conflict, there may be hope for a constructive dialogue among these groups.
132

Simulation and Analysis of Feedforward Automatic Gauge Control for a Hot Strip Finishing Mill

Chen, Po-Tsang 03 July 2002 (has links)
Recently, the accuracy of hot strip gage is strictly demanded, and the strip thickness becomes the most important quality in hot strip rolling. It is well known that the accuracy of final strip thickness in the hot strip mill depends on the gage control performance at each stand. In order to improve the quality of the hot strip gage and reduce the strip thickness deviation , the Automatic Gage Control(A.G.C) system now is widely used in modern hot strip mills of the world. In this paper, the principle of feedforward control strategy in the AGC system is discussed and it¡¦s control performance is deeply analyzed. Besides, based on the study of comprehensively mathematical model and the establishment of simulator, the mathematical analysis and the simulation result can clarify the influence of the control system on strip thickness.
133

Effect of Minimum Quantity Lubrication on Tool Wear and Surface Roughness in Micro Milling

Chou, Shih-yen 12 August 2009 (has links)
Product miniaturization is a long-term trend. Mechanical micro-machining is a suitable technique for manufacturing of microstructures characterized by cheap equipments, less working time, and possible complex geometry. For the requirements for high precision manufacture, the use of minimum/minimal quantity lubrication (MQL) is a good strategy for micro-machining due to long tool life and high product accuracy. This study presents an experimental investigation of the MQL in micro milling. The tool wear, surface roughness, and burr formation are observed at different feeds (1 £gm/rev, 1.5 £gm/rev, and 2 £gm/rev) and cutting speeds ( 37.7 m/min, 56.55 m/min, and 75.4 m/min) under dry and MQL cutting. Unlike conventional milling, greater tool wear is observed at lower feeds. Compared with the same cutting condition for dry cutting (feed 2 £gm/rev, cutting speed 56.55 m/min), MQL can reduce the tool wear about 56%. In terms of the consumption of the cutting fluid, oil flow rate of 1.88 ml/h is sufficient for reducing the tool wear in micro milling. According to the experimental results, deterioration of surface finish and burr formation are closely related to the tool wear. The use of MQL, not only reduces the tool wear, but also diminishes the deterioration of surface finish (the improvement of Ra is at least 0.6 £gm) and the burr formation.
134

Baseline survey and habitat analysis of aquatic salamanders in the Pigeon River, North Carolina

Maxwell, Nikki J 01 December 2009 (has links)
The Pigeon River was severely impacted beginning in the early 1900s by a paper mill located in Canton, North Carolina. The mill discharged chemical byproducts into the Pigeon River until 1992 when the paper mill modified their processes. As a result, water quality improved but the status of salamander species in the Pigeon River was unknown. Worldwide amphibian declines over the last 20 years have drawn attention to the need for more research and a better understanding of species-specific habitat relationships. There is concern about amphibian population declines because amphibians are critical to the balance of ecosystems and are considered exceptional indicators of environmental health.The objectives of this study were: 1) to conduct a baseline survey of salamander species composition in the Pigeon River watershed, 2) to determine if salamander populations differ above and below the Canton paper mill, and 3) to attempt to explain variance in salamander abundance, richness and diversity by comparing water quality and substrate characteristics among streams. Eight stations were examined on the Pigeon River, with four stations located above the paper mill and four stations below. We also chose three stations on each of four tributaries, Big Creek, Fines Creek, Jonathan Creek and Richland Creek. Snorkel surveys were completed in the summer of 2009. Five of eight species of stream salamanders were found that historically existed in Haywood County, NC: Eastern hellbender, Blue Ridge two-lined salamander, shovel-nosed salamander, black-bellied salamander and spring salamander. No salamanders were found in the main channel of the Pigeon River below the mill. Eastern hellbenders and Blue Ridge two-lined salamanders preferred substrates consisting of rubble and avoided bedrock. Percent rubble was the only variable retained in substrate models and was positively related to salamander abundance, richness and diversity. Conductivity, salinity, and water temperature were higher in the Pigeon River below the mill than at all other sites. Salamander abundance was explained by dissolved oxygen, pH, and stream width in water quality models. The results of this study suggest salamander abundance was negatively associated with the Pigeon River below the mill because of poor water quality and not habitat availability.
135

Gibbon, Mill und Ruskin : Autobiographie und Intertextualität /

Meyer, Michael, January 1998 (has links)
Habil.-Schr.--Bamberg--Univ., 1996. / Bibliogr. p. 215-245.
136

Evaluation of Flatness Gauge for Hot Rolling Mills

Larsson, Oliver January 2015 (has links)
In the steel industry, laser triangulation based measurement systems can be utilizedfor evaluating the flatness of the steel products. Shapeline is a company in Linköpingthat manufactures such measurement systems. This thesis work will present a series ofexperiments on a Shapeline measurement system in a relatively untested environment, thehot rolling mill at SSAB in Borlänge.The purpose of this work is to evaluate how the conditions at a hot rolling mill affectsthe measurement performance. It has been anticipated that measuring in high temperatureenvironment would introduce difficulties that do not exist when measuring in cold environments.A number of different experiments were conducted, where equipment such as laserand camera bandpass filter were alternated. Via the experiments, information about noisedue to the environment in the hot rolling mill was gained. The most significant noise wascaused by heat shimmering. Using the presented methods, the magnitude and frequencyspectrum of the heat shimmering noise could be determined. The results also indicates thatheat shimmering cause large errors and is quite troublesome to counter. In addition to this,the quality of the line detections under the hot rolling mill circumstances was examined. Itcould be observed that the line detections did not introduce any significant errors despitethe harmful conditions.
137

GC-MS Screening and PCB Analysis of Sediment from Central Kattegat

Eriksson, Emma January 2015 (has links)
Five sediment samples were collected in Bua on the Swedish west coast, near two industries, a paper mill, and a nuclear power plant. The two industries use water in their processes and have long been associated with releases of different substances, such as PCBs, and other chlorinated compounds. The environmental impact by the two industries is believed to be significant. The aim of the project was to examine the sediments close to both the water intake and water output to determine if these industrial activities have in any way changed the composition of the sediments. The sediments were extracted by Soxhlet extraction, followed by a deactivated silica and an acidic silica clean-up and then analysed by using a gas chromatograph coupled to a mass spectrometer, (GC-MS) with electron ionization, EI+, mode used in full scan mode. Each mass spectra were analysed by comparing them to the NIST database from 1998. The results were inconclusive since the peaks were not properly resolved, causing a poor correlation to the NIST database. One batch was specifically analysed for polychlorinated biphenyls (PCB) by using an atmospheric pressure gas chromatograph (APGC) coupled to a mass spectrometer (MS). The PCB analysis provided accurate results, except for the Ringhals intake where the MS became saturated due to the high levels. The river Viskan also showed high levels of PCB. The congener pattern from PCBs found near Ringhals intake resembled an Aroclor pattern from Aroclor 1248. Since the Aroclor pattern is only seen in Ringhals intake, the source is most likely from the small harbour and not from either of the industries.
138

Electrical, mechanical and residual stress interactions in minerals comminution

Partridge, Anthony Charles January 1974 (has links)
No description available.
139

Monitoring populations of the flour beetles Tribolium confusum Jacquelin du Val and Tribolium castaneum (Herbst) in flour mills and in laboratory settings

Hawkin, Karen 14 July 2008 (has links)
This thesis reports the effects of disturbance and harbourage on the fitness of Tribolium confusum and T. castaneum, as well as the the efficacy of pheromone monitoring traps for monitoring for populations of Tribolium in laboratory and mill settings. Behavioural studies were also carried out on mill and laboratory-reared beetles and the distributions of both species in a mill were examined. Twenty-four hour sieving disturbance decreased the rates of dispersal for both species, and decreased T. castaneum fecundity. Rolling disturbance decreased T. confusum dispersal rate while shaking disturbance decreased T. castaneum dispersal rate. When undisturbed beetles were given differing amounts of flour in the presence or absence of harbourage, beetles laid more eggs in larger amounts of flour, but harbourage only affected T. castaneum at one level of flour (2 g). Throughout disturbance and harbourage experiments, T. castaneum laid more eggs than T. confusum. Pheromone monitoring traps placed in three Canadian flour mills were not useful in predicting the degree of infestation inside Simons rollstands. Pheromone monitoring traps also showed low efficacy (i.e. caught few beetles) in both mill and laboratory settings, and T. confusum was caught less often than T. castaneum in both mills and in a warehouse. Mill-strain beetles of both species were caught less often than laboratory-strain beetles in a warehouse. In one Canadian flour mill, both T. castaneum and T. confusum were found inside rollstands but the two species were spatially segregated from one another, rarely being found together in the same rollstand. In contrast to this, both species were consistently found together in samples taken from the same mill less than a year beforehand. In behavioural laboratory studies, beetles collected directly from a mill moved slower than beetles collected from a laboratory culture and this response was shown to be phenotypic. Mill-strain and laboratory-strain beetles also differed in burrowing tendencies, with T. confusum from the laboratory strain burrowing less than T. confusum from a mill and T. castaneum from different mills sometimes burrowing more and sometimes less than T. castaneum from the laboratory strain.
140

Återvinning av dryckeskartonger : En studie som syftar till att öka återvinningsgraden av Tetra Paks förpackningar i Indonesien / Recycling of beverage cartons : Increasing Tetra Paks recycling rate in Indonesia

Backlund, Per January 2014 (has links)
People of the modern world consume more than they ever used to do. Because of the close correlation between consumption and the amount of waste, the waste volume is also expected to increase. The purpose of this study is to examine if some measures in the recycling process from Sweden could be implemented in Indonesia. In fact, Indonesia is one of the countries in which the waste management system is struggling. Tetra Pak, one of the world leading producer of food packaging, is studied in this report. Tetra Paks recycling rate of their beverage cartons is relatively low, 8.42 %, in Indonesia compared with their recycling rate in other countries. To answer the purpose, information was collected from scientific reports, by interviews carried out in both Sweden and Indonesia and by study visits in Indonesia. The results of the study shows that there are measures which could be made in the recycling process to increase the recycling rate in Indonesia. School projects and deposit systems could increase the collection rate and a drumscreen and a buffertank could make the recycling process more profitable for the papermills. There is also some alternative end products which could make the whole recycling process more public visible. One of the conclusions of this study is that the paper mills should adjust their drumscreens, this to increase the fibre yield which is crucial for the recycling value. Another conclusions is that Tetra Pak should consider to initiate a recycling business by their own, in order to reduce the burden on the environment.

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