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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.
231

Distributed Crawling of Rich Internet Applications

Mir Taheri, Seyed Mohammad January 2015 (has links)
Web crawlers visit internet applications, collect data, and learn about new web pages from visited pages. Web crawlers have a long and interesting history. Quick expansion of the web, and the complexity added to web applications have made the process of crawling a very challenging one. Different solutions have been proposed to reduce the time and cost of crawling. New generation of web applications, known as Rich Internet Applications (RIAs), pose major challenges to the web crawlers. RIAs shift a portion of the computation to the client side. Shifting a portion of the application to the client browser influences the web crawler in two ways: First, the one-to-one correlation between the URL and the state of the application, that exists in traditional web applications, is broken. Second, reaching a state of the application is no longer a simple operation of navigating to the target URL, but often means navigating to a seed URL and executing a chain of events from it. Due to these challenges, crawling a RIA can take a prohibitively long time. This thesis studies applying distributed computing and parallel processing principles to the field of RIA crawling to reduce the time. We propose different algorithms to concurrently crawl a RIA over several nodes. The proposed algorithms are used as a building block to construct a distributed crawler of RIAs. The different algorithms proposed represent different trade-offs between communication and computation. This thesis explores the effect of making different trade-offs and their effect on the time it takes to crawl RIAs. We study the cost of running a distributed RIA crawl with client-server architecture and compare it with a peer-to-peer architecture. We further study distribution of different crawling strategies, namely: Breath-First search, Depth-First search, Greedy algorithm, and Probabilistic algorithm. To measure the effect of different design decisions in practice, a prototype of each algorithm is implemented. The implemented prototypes are used to obtain empirical performance measurements and to refine the algorithms. The ultimate refined algorithm is used for experimentation with a wide range of applications under different circumstances. This thesis finally includes two theoretical studies of load balancing algorithms and distributed component-based crawling and sets the stage for future studies.
232

Materials evaluation of high temperature electrical wires for aerospace applications

Wang, Zijing January 2014 (has links)
The electrical resistivities of typical AWG20-Class3 and AWG18-Class27 Ni-coated Cu wires were monitored at 400 ºC for times up to 5500 hours; the resistivities increased by 6.9% and 2.3%, respectively. Microstructural analysis of the thermally aged wires revealed evidence of Ni-Cu interdiffusion. Diffusion experiments were performed on Ni-Cu metal foils in the range 400 to 600 ºC; Ni-Cu compositional profiles across the Ni-Cu interface were collected by energy dispersive X-ray spectrometry. Ni-Cu interdiffusivities determined by the Boltzmann-Matano method were typically 2.5×10-17 m2s-1;calculated activation energies for Ni-Cu interdiffusion were between 79.4 and 89.8 kJ•mol-1. Analysis of the available Ni-Cu interdiffusion data suggested a dependence on grain size of the Cu foils used. A concentric-circle, diffusion-resistivity model was developed. Using the experimentally determined Ni-Cu interdiffusion data, it was possible to accurately predict the resistivity of a Ni-coated Cu wire at 400 ºC as a function of time. It is predicted that the resistivity of the AWG20-Class3 wire would increase by 10% after annealing for 48,000 hours at 400 ºC; in contrast, heating an AWG18-Class27 wire for a much longer time of 140,000 hours would incur the same increase in its resistivity. Low temperature co-fired ceramics (LTCC) with a formulation of 11ZnO-10MoO3 (NSZM) were prepared with additions of 0.5 to 2.0 wt% B2O3 via the mixed oxide route. The NSZM samples were sintered at 850-950ºC to over 96% of theoretical density with co-existence of both ZnMoO4 and Zn3Mo2O9 phases. With increasing the addition of B2O3 to NSZM the relative permittivity, dielectric strength and thermal conductivity increased. NSZM prepared with 1.0 wt% B2O3 exhibited a relative permittivity of 11.1, dielectric strength of 17.6 kV•mm-1, linear thermal expansion of 4.7 ppm•K-1and thermal conductivity of 1.3 W•m-1•K-1. The LTCC material is a possible candidate for insulating applications because of its low dielectric constant and adequate dielectric strength. LTCC insulation films were applied to Ni disc substrates by dip coating; the suspensions contained 5 to 20 vol% NSZM ceramic powders, 1.0 wt% B2O3, a polyvinyl butyral (PVB) based binder system, plus solvents and organic additives. A microstructural study of the LTCC films revealed that the insulation thickness varied from 4.3 to 47.3 µm with the ceramic content of starting suspension. The dielectric strength of these films was in the range 24.2 to 43.7 kV•mm-1. These results showed that dip coating is a promising method for applying the LTCC insulation to Ni-based metal substrates. LTCC-insulated wires were manufactured by withdrawing Ni-coated Cu conductors from the suspension, containing 15 vol% ceramic powders, followed by co-firing at 500 ºC. The LTCC-coated wire exhibited an insulation thickness of 40.3 µm and a breakdown voltage of 798 V. These results suggest that the LTCC-coated wire is a possible candidate for use in high temperature machine windings.
233

Analyzing photographs in archival terms

Barr, Debra Elaine January 1985 (has links)
Through a comparison of the literature produced by general archival theorists with that published by photographic archivists, it becomes clear that archival principles are not routinely applied to records in photographic form. Since reflecting knowledge about records creators and circumstances of creation is a basic archival responsibility, this thesis will begin with a discussion of a variety of past and present purposes of photographers in general. The ways in which both purposes and methods can influence photographic information will also be studied. The obligation of photographic archivists to examine records and creators in terms of administrative (including legal), scholarly and other user values will then be examined. The thesis will conclude with a survey of the literature produced by North American photographic archivists to determine whether their responsibilities are fully recognized. / Arts, Faculty of / History, Department of / Graduate
234

Problems and issues in the arrangement and description of photographs in libraries and archival repositories

Cobon, Linda Louise January 1988 (has links)
Until recent years, archivists have been reluctant to consider photographs as being archival in nature. The evidential value possessed by some photographs was ignored and archivists also failed to see where the informational value of a photographic image could be enhanced when viewed within the context in which it was created. Instead, archivists preferred to arrange and describe photographs as discrete items. For assistance in this endeavor, archivists turned to members of the library profession. Librarians, for their part, found that photographs were not amenable to standard bibliographic formats or classification schemes devised for printed monographs. The result was the creation by members of both the library and archival professions of numerous and often idiosyncratic methods for the physical and intellectual control of photographs. The volume of photographic images acquired by libraries and archival repositories now makes it virtually impossible to continue dealing with photographs as discrete items. The research needs and methodologies of users have also changed; photographs are increasingly being sought as historical documents in their own right and not just as illustrations to accompany the written word. In response to these two factors, librarians began organizing and describing photographs as "lots" and archivists moved slowly toward the arrangement and description of photographs as archival fonds. This evolution, far from complete with regard to photographs, resembles an earlier evolution affecting the arrangement and description of textual archives, particularly manuscripts. Today archivists in many Western countries are seeking to establish standard formats in the description of archival materials. This goal has become particularly urgent in the face of computer technology and the desire to form automated archival networks. It remains to be seen whether the final standards adopted in Canada, for instance, will encompass photographs or whether photographs will retain a "special" status. Without question, photographs have and will continue to present members of the library and archival professions with problems In arrangement and description. This is demonstrated in the body of this thesis through a survey of the professional literature and through field work undertaken in six libraries and archival repositories in the Vancouver area and in Victoria, British Columbia. However, the existence of problems should not mean that the approach to photographic archives should be any different, in essence, from the approach and principles applied to textual archives. / Arts, Faculty of / Library, Archival and Information Studies (SLAIS), School of / Graduate
235

Degradation of sawdust by Cellulomonas fimi enzymes

Vondette, Nancy Anne January 1982 (has links)
Cellulomonas find was grown on minimal media with casamino acids and yeast extract added. Avicel was found to be the best cellulosic carbon source for the production of cellulase enzymes. The Millipore Ultrafiltration System was found to be the most efficient method of concentrating the enzyme preparations. Unpretreated sawdust samples of four different softwood species were degraded between 12 and 16 percent over a 15-day treatment. Increasing the concentration of substrate lead to a lower percent degradation but a higher overall degradation. Chemical pretreatment did not appreciably increase degradability of the samples. Physical pretreatments decrease the degrada-bility of the sawdust samples. The lotech pretreatment, which is a combination of chemical and physical pretreatment, gives a substrate that is degraded by the Cellulomonas fimi enzyme preparation. The pretreatment makes 50% of the sample water soluble. In 3 days, a further 35% is degraded from large insoluble chunks into insoluble small particles which remain in suspension. There is 6% degraded into soluble state. This leaves only 9% of the initial sample left in the pellet. With longer incubation, one would expect the degradation to continue. / Science, Faculty of / Microbiology and Immunology, Department of / Graduate
236

The structure determination of three inorganic and two organic compounds by x-ray diffraction

Mercer, Anthony January 1977 (has links)
This thesis deals with the current methods available for X-ray structure determination and with the crystal and molecular structure determination of five compounds using these methods. The five compounds are 1) [ 2,3-Bis (dimethylarsino)- 1, 1, 1,4, 4, 4-hexaf luorobut-2-ene-As,As]tricarbonyldiiodotungsten(II),Me₂AsC (CF₃):C (CF₃) AsMe₂WI₂(CO)₃ 2) Dimethylammonium trichlorotris(dimethylsulphoxide}-ruthenate(II) , [ ( (CE₃)₂ SQ)₃ RuCl₃ ]⁻ [ (CH₃)₂ NH ₂]+ 3) Dichlorotetrakis{dimethylsulphoxide)ruthenium(II), (Me₂SO)₄fRuCl₂ 4) 1,3,7-Triraethyl-2,6-dioxypuriae hydrochloride dihydrate (caffeine hydrochloride dihydrate), CH₁₁C1N₄0₂-2H₂0 .5) 1-Acetyl-3-benzamido-2-keto-4- (2,3, 4, 6-tetra-O-acetyl-β-D-glucopyranosyloxy)-Δ³-pyrroline, C ₂₇H₃₀N₂O₁₃ The structures of compounds 1), 2), and 3) were determined by Patterson syntheses, compound 4) by centrosymmetric direct methods and compound 5) by non-centrosymmetric direct methods. All structures were then refined using full-matrix least-sguares procedures. The relevant crystal data for all five compounds can be found in Table A In the tungsten compound [1) the tungsten atom is seven-coordinate with a distorted capped octahedral environment, the capping group being a carbonyl. The capped face consists of the two remaining carbonyl groups and one of the arsenic atoms from the bidentate ligand. The uncapped face contains the two iodine atoms and the remaining arsenic. Crystal data for the five compounds examined atom. The structure of the ruthenium compound [ 2) ] consists of two crystallcgraphically non-equivalent anions in the asymmetric unit linked by hydrogen bonding via dimethylammonium cations. The coordination geometry about the structurally similar anions is essentially that of an octahedron with the DHSO ligands being bonded to Ru via the sulphur atoms. The co-ordination geometry about the ruthenium atom for compound 3) is essentially octahedral with cis chlorine atoms; Of the four DMSO ligands three are S-bonded and one is O-bonded, the O-bonded ligand being trans to a S-bonded ligand. For caffeine hydrochloride [ 4) ] the fused ring system is essentially planar and protonated at the 9-positioh. The crystal contains two types of hydrogen bonding involving 0-H...C1 and N-H...0 interactions. The structure of compound 5) consists of a pyranose ring in the chair conformation with the four 0-acetyl substituents in equatorial positions; the pyranose ring is connected to a planar pyrroline ring via a β-oxygen bridge. / Science, Faculty of / Chemistry, Department of / Graduate
237

Job applicants' age, gender, and exercise lifestyle as determinants of evaluations of hiring application forms

Kaiser, Sally Allene 01 January 1993 (has links)
No description available.
238

Experimental study of the mechanical effect of a clayey soil by adding rubber powder for geotechnical applications

Alvarez, N., Alvarez, N., Gutierrez, J., Duran, G., Pacheco, L. 28 February 2020 (has links)
At present, worrying quantities of tires are discarded due to the growth in demand for vehicles in the world, which has a direct impact on the deterioration of the environment since they normally go to landfills. Based on the background found, the use of this material for geotechnical applications can help reduce the pollution they generate and improve the physical and mechanical properties of soils. Therefore, this research seeks to evaluate a greater shear strength and capacity of support to the penetration of the clayey soil by means of the addition of 1.5%, 2.5% and 3.5% of rubber powder recycled. For this, the Atterberg limits analysis, the modified proctor compaction test, shear box and CBR were performed. For the shear box test, the results reflect that the cohesion of the mixture increased and the angle of internal friction decreased with respect to the natural soil, resulting in the sum in an increase of shear strength. On the other hand, the percentage of CBR increased, this means that the rubber helped the soil to be more rigid and have a greater resistance to penetration. These mixtures could be used in different projects within geotechnical engineering, as it presents an improvement in shear strength and an acceptable support index value (CBR).
239

Supporting mobile developers through a Java IDE

Ogunleye, Olalekan Samuel January 2008 (has links)
Includes bibliographical references (pages 95-105). / There exist several challenges in supporting mobile applications. For example, creating a separate target application for each device type, leaving developers with a huge maintenance chore. Most desktop applications run on largely homogenous hardware so instead of writing the same code over and over again, developers only need to write modules to implement a particular need. This is because even though there are differences in PC hardware configurations, the same desktop application will work fine on any hardware as the operating system provides an abstract layer. This is the way mobile applications are expected to work. However, this has been divided into dozens of ill-assorted versions. Java mobile applications developers spend more time rewriting code to run on different versions of mobile devices more than they do actually creating application in the first place. This is an intolerable burden for small mobile developers, and it stifles mobile software innovation overall. Mobile devices differ in a variety of attributes, such as screen size, colour depth and the optional hardware devices they support such as cameras, GPS etc. The differences often require special code or project settings for successful deployment for each device a developer is targeting but this creates a huge logistical overhead. One potential solution that is shipped with NetBeans IDE is to add a new configuration for each device, modify the project properties, add some pre-processing code, then build and deploy the application. In most cases, one configuration for each distribution of the Java Archive (JAR) one plans to build for the project is created. For example, if a developer is planning to support three· different screen sizes using two sets of vendor specific APIs, one needs to create six configurations. This reduces the performance of the application drastically and increases the size at the same time. This is not acceptable for mobile devices where memory size and processor performance are limited. The goal of this research work is to support mobile application development through a Java IDE (the NetBeans IDE in this case). Therefore, our approach will be to modify the NetBeans IDE to better address the difficulty that was mentioned above - namely targeting applications for different platforms. Our solution is to integrate another type of a preprocessor into the NetBeans IDE that will help alleviate the problems of the existing tool. Our approach is to directly implement this inside the NetBeans IDE to further support mobile application development with the NetBeans IDE.
240

Pedagogical Applications of Scat-singing Within the Jazz Trombone Studio

Schneller, Aric Lewis 08 1900 (has links)
This study investigates the pedagogical applications of scat-singing within the jazz trombone studio. In addition to the obvious ear-training benefits that the student player can gain from this synthesis, the palette of articulation subtleties and overall musically expressive qualities for trombonists can also be greatly enhanced. These commonalities will encompass the pedagogical focus of this document, utilizing performance recordings and publications by prominent jazz artists and writers to document existing teaching strategies as well as develop new concepts. The first section of this document presents an introduction that includes a historical overview of scat-singing, prominent scat-singing instrumentalists, and concepts and current literature. The second section presents selected biographies on Wycliffe Gordon and Bill Watrous, both prominent jazz trombonists who sing as well as play the trombone. The third section investigates jazz articulation, scat-singing articulation, and doodle-tongue articulation and their relevance to this topic. The fourth section explores musically expressive qualities as analyzed in Bill Watrous’ solo transcription of “Body and Soul.” The final section draws conclusions about the pedagogical applications of scat-singing within the jazz trombone studio and summarizes current teaching strategies. Although this document is not a performance guide, an informed performance of the concepts and examples contained herein is required.

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