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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

Reflective cracking of shear keys in multi-beam bridges

Sharpe, Graeme Peter 02 June 2009 (has links)
Multi-beam bridges made from precast concrete box girders are one of the most common bridge types used in the United States. One problem that affects these bridges is the development of longitudinal or reflective cracks on the road surface because of failure of the shear keys. Some states have attempted to correct this problem by redesigning the shear key or adding post-tensioning, but the problem persists in many new bridges. The purpose of this study is to investigate why these shear key failures are occurring. This project studies two types of box girder designs, the common Precast/Prestressed Concrete Institute (PCI) box girder bridges and the Texas Department of Tranportation (TxDOT) box girder bridge. In the past, reflective cracking has occurred in bridges of both types. The analysis procedure involves finite element analyses of bridge models with realistic support and loading conditions, and comparing the PCI and TxDOT bridges. The results indicate that both PCI and TxDOT box girder have sufficient strength to resist cracking from vehicular loads, but uneven temperature changes and shrinkage strains cause high tensile stresses in the shear key regions and lead to reflective cracking. The analyses showed the highest stresses were often times near the supports, rather than at midspan. Past studies have proposed using larger composite deck slabs, transverse posttensioning, or full-depth shear keys to prevent shear key failure. Composite slabs were the most effective way to reduce high stresses in shear keys, and were effective for all loading cases considered. Post-tensioning and full-depth keys also showed a reduction in shear key stresses, but were less effective.
62

Design and Construction of a Guarded Hot Box Facility for Evaluating the Thermal Performance of Building Wall Materials

Mero, Claire Renee 2012 May 1900 (has links)
The focus of this study was to design and build a guarded hot box to test the R-Value of building materials. The Riverside Energy Efficiency Laboratory is looking to expand their testing capabilities by including this service. Eventually, the laboratory will become energy star certified. A guarded hot box facility consists of two boxes maintained at specific temperatures and a guard box around each one that is maintained at the same temperature as the box it surrounds. The ASTM C1363 standard was used as guide for the construction and testing of sample specimen. This standard called for an air velocity profile uniform within 10 percent of the average. Velocity tests were performed with various different configurations to give a uniform velocity. Although the velocity did not meet standards, the configuration chosen included a piece of 1/4" pegboard placed 2" away from the top and the bottom of the inner box. By using the known overall heat added and removed from the system, as well as all the heat losses the heat transferred through the specimen and its R-Value can be calculated. The uncertainty of the R-Value and the accuracy of the testing facility gave conflicting results. Future experiments will use improved testing methods that include differential thermocouples to obtain better uncertainty for the R-Value calculations.
63

The Relationship between the Awarded-Winning Movies of Taiwan and the Box Office

Yin, Chia-lien 14 March 2006 (has links)
Since ¡§The City of Sadness¡¨ won the first Golden Lion Award of International Venice Film Festival, winning an international award has become a rule that Taiwanese film do its marketing strategy. However, although ¡§The City of Sadness¡¨ created a high profit in its sales, other awarded movies seem not so lucky in the sales performance. This research mainly bases on the aspect of marketing to study the phenomenon that Taiwanese film industry devotes in attending international film festival as its marketing strategy and further to analyze the relationship between the movie box office and this phenomenon. Secondary data would be employed in this research. As a result, besides ¡§The City of Sadness¡¨, both ¡§The Wedding Banquet¡¨ and ¡§Crouching Tiger Hidden Dragon¡¨ also have good performance in their sales. However, the success of these two movies not only resulted from getting awards but also the stories of the movies could attract people to go to the theater. According to the result of this research, we can find that there are more than 400 international film festivals in the world, but only Oscar Award is related with the sales of the film. On the other hand, other film festivals have not been able to attract people as much as ¡§The City of Sadness¡¨ did. Moreover, this situation also can prove one thing: the movie should be developed by commercial mode in order to be accepted by most audiences. To sum up, Taiwanese movies are on purpose (e.g. increase profit and government support) to attend international film festival. However, there are not any benefits to the market of the Taiwan movie and it will let audiences to be distant from their owner entertainments product of their country. If Taiwan government cannot identify the real direction of the Taiwan movies, there is no future of Taiwan movies.
64

none

Huang, Yen-ning 19 July 2008 (has links)
It¡¦s everyone¡¦s dream to have their own career in their life, such as running a restaurant or a store. Although the economy has been depressed for a long time, there are more and more restaurants in Taiwan. Running a lunch-box store is one of the options when people want to have their own stores. Some people successed and had the chain lunch-box stores, even planned to enter China market. Some failed in running their stores and left the market. This research would focus on the operation of the lunch-box store to find what to do to make the store better operated.
65

Top-lateral bracing systems for trapezoidal steel box-girder bridges

Chen, Brian Scott. Yura, J. A. Frank, Karl H. January 2002 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2002. / Supervisors: Joseph A. Yura and Karl H. Frank. Vita. Includes bibliographical references. Available also from UMI Company.
66

The box

Leahy, Katherine Lee 28 June 2012 (has links)
This project explored a new work in the lighting and video area of the entertainment industry. This thesis archives the creative process of this specific new piece, resulting in a realized and finished work open to the public. The Box opened in the Oscar Brockett Theater on the University of Texas at Austin campus on March 19, 2012, and ran from 10 am to 7 pm for three days. The Box was an installation piece of art that told a story. This seemingly simple structure of a large black box contained a surprising inner life. The sculpture had an opening cut into its side, which upon entering transports the viewer into a space with a modified perspective. More than one person can view the piece at a time. Visitors entered the box and became immersed in a world of manipulated lighting, video, and sound. Characters existed in the form of animated light, color, and audio. These characters expressed elemental energies of air, fire, earth, and water that communicated primal emotions. The Box wove a narrative fabricated from lighting, animation, sound, and manipulation of perspective, without using traditional methods of storytelling such as actors or speech. While The Box was on display, viewers visited multiple times and interacted with the environment in different ways. Dancers danced in The Box, actors delivered monologues, and some viewers simply lay on the floor and became part of the art itself. / text
67

Finite element modeling of post-tensioned box girder bridges

Zaoui, Ahlem 08 1900 (has links)
No description available.
68

Molecular Characterization of MADS-BOX Transcription Factors and Analysis of Field Population Diversity in the Maize Pathogen Fusarium verticillioides

Ortiz, Carlos S 03 October 2013 (has links)
Fusarium verticillioides (Teleomorph Giberella moniliformis) is an ascomycete fungus responsible for ear and stalk rots of maize. Most importantly, it produces a group of mycotoxins called fumonisins upon colonization of maize kernels. Fumonisin B1 (FB1), the most prevalent fumonisin in nature, was first identified in 1988 and has been found to be toxic to human and animals. The gene cluster for FB1 biosynthesis and some environmental conditions responsible for the toxin production are known, but gaps in our understanding of the signaling pathways leading to FB1 biosynthesis still remain. MADS-box transcription factors (TF) are known to regulate diverse cellular functions in all eukaryotes, and in silico analyses revealed two genes, MADS1 and MAD2, in F. verticillioides. Reverse genetics studies indicated that MADS1 and MADS2 positively regulate sexual mating and FB1 biosynthesis but not pathogenicity in F. verticillioides. Furthermore, MADS1 was found to act as a broad regulator of polyketide-derived secondary metabolism. Additionally, population diversity studies were conducted in 164 F. verticillioides cultures isolated from 65 maize-producing counties in Texas. The result showed a fluid population with no particular niches formed. F. verticillioides strains were also isolated from counties that have previously tested negative for FB1 contamination in maize. The presence of the pathogen represents a risk for future FB1 contamination events if suitable conditions were to arise. My research revealed new genetic components involved in F. verticillioides secondary metabolite biosynthesis and provided a better understanding of the pathogen population fluidity in Texas.
69

The reproductive strategies of the pill-box crab Halicarcinus innominatus Richardson, 1949

Dunnington, Michael James January 1999 (has links)
This study examines the reproductive strategies of the Pill-box crab, Halicarcinus innominatus, at the Oaro Platform (24 km south of the Kaikoura Peninsula, New Zealand). As necessary components of reproductive strategies, the population dynamics, reproductive biology and mating behaviour of H. innominetus were examined from December 1997 through December 1998. There were obvious sexually dimorphic differences in secondary sexual traits in this species. Both males and females display a wide range of sizes over which individuals can moult to maturity. H. innominatus females displayed continuous breeding throughout the year, resulting in continuous recruitment. Females were found to outnumber males in each month. However, when comparisons were made between mature males and females with different brood stages (i.e. 0-5), males outnumbered each female type in each month. Investigations into the reproductive biology of H. innominatus females revealed that brood development and ovary development were in phase. This resulted in the ability of females to produce several broods in quick succession. Ovary development began before the moult to maturity, allowing for immediate production of a brood after the moult to maturity. Egg incubation periods were dependent on water temperature, being longest in the winter and shortest in the summer. Egg numbers were found to increase with female body size, but mortality of eggs through development was apparent. Sperm storage was found to occur in this species with possible layering of different ejaculates. Copulations were only observed between males and females in hard-shell conditions. Males mated more often with females carrying stage 5 broods, but also mated with all other female types, including pre-pubescent females. Postcopulatory mate guarding only occurred with stage 5 females. Males can detect females of different reproductive condition, which seems to be linked to the developmental stages of the females' ovaries. In conclusion, H. innominatus males seem to have two tactics to their reproductive strategies: mating with any receptive female, but only guarding stage 5 females.
70

Nondestructive testing of concrete box girder bridges using thermal imaging

Dupuis, Kenneth J., January 2008 (has links) (PDF)
Thesis (Master of Civil Engineering)--Washington State University, May 2008. / Includes bibliographical references (p. 93).

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