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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.
401

Attaching Social Interactions Surrounding Software Changes to the Release History of an Evolving Software System

Baysal, Olga January 2006 (has links)
Open source software is designed, developed and maintained by means of electronic media. These media include discussions on a variety of issues reflecting the evolution of a software system, such as reports on bugs and their fixes, new feature requests, design change, refactoring tasks, test plans, etc. Often this valuable information is simply buried as plain text in the mailing archives. We believe that email interactions collected prior to a product release are related to its source code modifications, or if they do not immediately correlate to change events of the current release, they might affect changes happening in future revisions. In this work, we propose a method to reason about the nature of software changes by mining and correlating electronic mailing list archives. Our approach is based on the assumption that developers use meaningful names and their domain knowledge in defining source code identifiers, such as classes and methods. We employ natural language processing techniques to find similarity between source code change history and history of public interactions surrounding these changes. Exact string matching is applied to find a set of common concepts between discussion vocabulary and changed code vocabulary. We apply our correlation method on two software systems, LSEdit and Apache Ant. The results of these exploratory case studies demonstrate the evidence of similarity between the content of free-form text emails among developers and the actual modifications in the code. We identify a set of correlation patterns between discussion and changed code vocabularies and discover that some releases referred to as minor should instead fall under the major category. These patterns can be used to give estimations about the type of a change and time needed to implement it.
402

Investigation of Hand Forces, Shoulder and Trunk Muscle Activation Patterns and EMG/force Ratios in Push and Pull Exertions

Chow, Amy 27 September 2010 (has links)
When designing work tasks, one goal should be to enable postures that maximize the force capabilities of the workers while minimizing the overall muscular demands; however, little is known regarding specific shoulder tissue loads during pushing and pulling. This study quantitatively evaluated the effects of direction (anterior-posterior pushing and pulling), handle height (100 cm and 150 cm), handle orientation (vertical and horizontal), included elbow angle (extended and flexed) as well as personal factors (gender, mass and stature) on hand force magnitudes, shoulder and L5/S1 joint moments, normalized mean muscle activation and electromyography (EMG)/force ratios during two-handed maximal push and pull exertions. Twelve female and twelve male volunteers performed maximal voluntary isometric contractions under 10 push and pull experimental conditions that emulated industrial tasks. Hand force magnitudes, kinematic data and bilateral EMG of seven superficial shoulder and trunk muscles were collected. Results showed that direction had the greatest influence on dependent measures. Push exertions produced the greatest forces while also reducing L5/S1 extensor moments, shoulder moments with the 150 cm height and overall muscular demands (p < 0.0001). The 100 cm handle height generated the greatest forces (p < 0.0001) and reduced muscular demands (p < 0.05), but were associated with greater sagittal plane moments (p < 0.05). Females generated, on average, 67% of male forces in addition to incurring greater muscular demands (p < 0.05). The flexed elbows condition in conjunction with pushing produced greater forces with reduced overall muscular demands (p < 0.0001). Furthermore, horizontal handle orientation caused greater resultant moments at all joints (p <. 0.05) The results have important ergonomics implications for evaluating, designing or modifying workstations, tasks or equipment towards improved task performance and the prevention of musculoskeletal injuries and associated health care costs.
403

Family Communication Patterns: Can They Impact Leadership Styles?

Prasitthipab, Suthida 01 August 2008 (has links)
A plethora of studies has worked on family communication and leadership separately. Little research has combined these two components although they both relate to personality characteristics and communication styles. Therefore, this thesis investigated correlations between leadership styles and family communication patterns during childhood. Two hypotheses were proposed representing the relationship between conformity orientation and task leadership, and between conversation orientation and relation leadership. Faculty, non-academic staff, and students in leadership positions from Western Kentucky University were samples of this study. They completed a questionnaire voluntarily. Family communication pattern scale and Leadership Behavior Descriptive Questionnaire were used in the survey. Pearson Product-Moment correlation (one-tail) was used to examine the two hypotheses. The first hypothesis was significantly supported. The results indicated a positive relationship between conversation orientation and relation leadership. Moreover, data showed that most respondents came from conversation-oriented families and used relation leadership styles.
404

The Conversation between Film and Ideology : How Wall Street and Wall Street. Money Never Sleeps promote and/or criticize financial capitalism?

Ye, Qijun January 2012 (has links)
The aim of this thesis is, within two films Wall Street and Wall Street. Money Never Sleeps, to explore characters from different levels of capitalism’s characteristics and ideological positions, what kind of society and ideological patterns the two films reflect and in which ways do the films promote and/or criticize capitalism. Theories on ideology and ideology critique are applied and used in a discourse analysis in order to compare characters of different levels of capitalism’s ideologies and characteristics over times in the films and describe what kind of society and ideological patterns the two films reflect. The outcomes show that characters’ ideologies and characteristics actually change over times in the films. And the outcomes also show that the two films generally promote capitalism by creating same model of story under different societies and ideological patterns.
405

2440x1220 : såga, sätt samman

Olofsson Rodenius, Pål January 2010 (has links)
I have been inspired by the Do It Yourself movement. DIY builds on the creativity of the individual, one’s capacity for initiative and one’s desire to realise one’s ideas. I have been inspired by sheets of pattern paper used in the manufacture of clothing, and my line of furniture is based on two-dimensional patterns of furniture. The sections of the pieces of furniture are printed on and relate to a standard sheet of plywood. In my project I provide tools for luring forth people’s ability to create and take their own initiatives. The project is aimed at those who are experienced in making furniture themselves and also those who have no experience at all. My intention is to encourage individual creativity and to communicate the idea that it is easy to create furniture. / Mitt möbelprojekt grundar sig i att försöka locka till att bygga själv. Jag vill förmedla ett redskap och en ingång till att på egen hand skapa möbler. Jag har alltid fascinerats av autodidakt design. Under min uppväxt var större delen av möblerna hemmasnickrade eller omgjorda av mina släktingar. Ett gammalt bord ifrån Dalarna, en tung furusäng snickrat av regelvirke, köksbord av spånskiva täckt med vitt kakel. Soffa ombyggd och omklädd med mönstrade tyger. Mitt kandidatarbete tar sig uttryck i mönsterark tryckta på plywoodskivor, anpassat efter plywoodskivornas standardmått 2440x1220mm. Det ger köparen inblick i processen att skapa en möbel. Att anpassa delarna efter skivans standardmått ger också minimalt med resursslöseri. Det påminner om den industriella tillverkningen av en möbel. Möbelns delar kommer att screentryckas i färger och skivans uttryck går mot det textila, både arbetssättet och förhållningssättet kommer mönsterkonstruktion av kläder. / Kandidatexamen 2010
406

Structural characterization of overrepresented

Lysholm, Fredrik January 2008 (has links)
Background: Through the last decades vast amount of sequence information have been produced by various protein sequencing projects, which enables studies of sequential patterns. One of the bestknown efforts to chart short peptide sequences is the Prosite pattern data bank. While sequential patterns like those of Prosite have proved very useful for classifying protein families, functions etc. structural analysis may provide more information and possible crucial clues linked to protein folding. Today PDB, which is the main repository for protein structure, contains more than 50’000 entries which enables structural protein studies. Result: Strongly folded pentapeptides, defined as pentapeptides which retained a specific conformation in several significantly structurally different proteins, were studied out of PDB. Among these several groups were found. Possibly the most well defined is the “double Cys” pentapeptide group, with two amino acids in between (CXXCX|XCXXC) which were found to form backbone loops where the two Cysteine amino acids formed a possible Cys-Cys bridge. Other structural motifs were found both in helixes and in sheets like "ECSAM" and "TIKIW", respectively. Conclusion: There is much information to be extracted by structural analysis of pentapeptides and other oligopeptides. There is no doubt that some pentapeptides are more likely to obtain a specific fold than others and that there are many strongly folded pentapeptides. By combining the usage of such patterns in a protein folding model, such as the Hydrophobic-polar-model improvements in speed and accuracy can be obtained. Comparing structural conformations for important overrepresented pentapeptides can also help identify and refine both structural information data banks such as SCOP and sequential pattern data banks such as Prosite.
407

Spatial Variation of Cardiac Restitution and the Onset of Alternans

Dobrovolny, Hana Maria 19 June 2008 (has links)
<p>Instability in the propagation of nonlinear electro-chemical waves in the heart is responsible for life-threatening disease. This thesis describes an investigation of the effects of boundaries on cardiac wave propagation that arises from a site where an electrical stimulus is applied or from boundaries beyond which current does not flow. It is generally believed that the spatial scale for boundary effects is approximately equal to the passive length constant, lambda, of the tissue, the distance over which a a voltage pulse decays when it is below the threshold for wave generation. From the results of <em>in vitro</em> experiments with bullfrog cardiac tissue and through numerical simulations, I find that boundaries affect wave propagation over a much larger spatial scale and that the spatial variation in some cardiac restitution properties is correlated statistically with the onset of alternans, a possible precursor to fibrillation in the human heart.</p><p>An optical imaging system using novel illumination based on LEDs is used to determine the spatial dependence of action potential duration (APD) and the slope of the dynamic restitution curve S<sub>DRC</sub>, which describes the relationship between steady-state APD and diastolic interval. For tissue with nearly identical cells, I find that APD is longest near the stimulus and shortest near the physical boundary with significant changes (~100 ms) over a distance of ~10lambda. S<sub>DRC</sub> decreases with distance from the stimulus at a constant rate (~0.1-1.5 /mm) over the surface of the tissue. Simulations using a two-variable cardiac model confirm that spatial patterns of APD and S<sub>DRC</sub> can be induced by boundaries.</p><p>Additional measurements with the simultaneous impalement of two microelectrodes are used to determine the spatial differences of other restitution properties. These studies indicate that APD and S<sub>DRC</sub>, as well as the slopes of the constant-BCL and S1S2 restitution curves, vary in space and that the spatial differences and onset of alternans at rapid pacing are correlated. If similar correlations are evident in humans, such measurements may identify patients who are susceptible to arrhythmias and allow for early treatment.</p> / Dissertation
408

Monitoring Marine Mammals in Onslow Bay, North Carolina, Using Passive Acoustics

Hodge, Lynne Elizabeth Williams January 2011 (has links)
<p>Passive acoustic monitoring is being used more frequently to examine the occurrence, distribution, and habitat use of cetaceans. Long-term recordings from passive acoustic recorders allow the examination of diel, seasonal, and inter-annual variation in the occurrence of vocalizing marine mammals. With the increased use of passive acoustics as a tool for studying marine mammals, the ability to classify calls to the species level is becoming more important. While studies have found distinctive vocalizations in some cetacean species, further work is required in order to differentiate the vocalizations of delphinid species. I sought to classify odontocete vocalizations to species and to describe temporal variation and depth-related differences in the occurrence of cetacean vocal events detected in archival passive acoustic recordings in Onslow Bay, North Carolina. To determine if odontocete species in offshore waters of North Carolina could be distinguished by their whistles and clicks, I used a towed hydrophone array to make acoustic recordings of species encountered during concurrent visual and acoustic surveys between 2007 and 2010. I recorded whistles from four species (Atlantic spotted dolphins, bottlenose dolphins, rough-toothed dolphins, and short-finned pilot whales) and clicks from five species (Risso's dolphins in addition to the four species listed above). After running a classification and regression tree (CART) analysis on 22 measured variables from the contours of four species' whistles, I generated an optimal classification tree that had a correct classification rate of 74.2%. My results indicate that species-specificity exists in the four species' whistles. My examination of the spectral structure of clicks showed that only Risso's dolphins produced clicks with distinctive spectral banding patterns, although I found that other click parameters, particularly peak and center frequency, might be useful in differentiating the other species. I then used the distinctive banding pattern that I observed in Risso's dolphin clicks to identify this species in recordings made by archival passive acoustic recorders that were deployed at various times and locations between 2007 and 2010. I used these recordings to determine how vocal events varied temporally and spatially in Onslow Bay. My analysis of vocal events observed in these recordings showed that Risso's dolphins, sperm whales, and other delphinids are present in Onslow Bay throughout the year; Kogia spp. occur sporadically; and fin and minke whales produce calls that can be detected only between late fall and early spring. I also detected low-frequency downsweeps and two types of low-frequency pulse trains produced by unknown species. After looking at the occurrence of fin whale 20-Hz pulses in relation to downsweeps, I suggest that the downsweeps are produced by sei whales due to the lack of overlap in occurrence. When I looked for diel patterns in the odontocete vocal events, I found a nocturnal increase in the occurrence of clicks from Risso's dolphins and sperm whales, but no diel variation in Kogia clicks. I also found that unidentified delphinids showed either an increase in click events at dawn or at night, depending on the time of year and recording location. Finally, my analysis of acoustic data from five recorders deployed in three different depth ranges revealed that there was greater unidentified delphinid and sperm whale vocal activity on recorders located in deep waters, suggesting a greater diversity and density of animals in deeper waters of Onslow Bay. Together, the results of my dissertation demonstrate the value of passive acoustic monitoring in understanding the distribution and temporal trends in cetacean occurrence, and highlight the importance of classifying sounds to the species level in order to better understand the temporal and spatial patterns found.</p> / Dissertation
409

Mercury accumulation of yellowfin tuna, Thunnus albacores, in Seychelles, Indian Ocean

Li, Hsin-hsien 06 September 2010 (has links)
Ninty three yellowfin tuna, Thunnus albacares, the fork length ranged from 80 to 168 cm were collected from the waters around Seychelles by two longline fishing vessels from April to December in 2006. The muscle and liver samples were analyzed for total mercury (THg) and organic mercury (OHg) concentrations.The concentrations of THg and OHg of the muscle were similar to previous studies. The concentrations of THg and OHg form the muscles and livers were positive-linearly regressed with the fish of Fork Length larger than 113 cm (big fish group), but only THg concentration of muscle was negative- linearly regressed 80- 112 cm (small fish group). Such patterns were first found in yellowfin tuna. It might be related to the ¡§growth rate¡¨ . Only one THg concentration of liver were over the standard set by the European Commission Decision (1 mg / kg THg wet wt.), other samples were in accordance with standard set by the European Commission Decision and the US-FDA food safty standard (1 mg / kg MeHg wet wt.). According to the dietary recommendations set by the Department of Health, Executive Yuan, yellowfin tuna can replace 86% animal protein source per week of people.
410

Order Aggressiveness of Informed Traders under Different Competitions of Trading and Correlations of Information

Wu, Po-ting 28 July 2011 (has links)
This paper refers to Ma and Hung(2004) using the amount of the institutional investors to measure the competitions of trading and the order flows of the institutional investors to measure correlations of information. We filter the data on daily basis and divide the data into four groups: high competition and high correlation, high competition and low correlation, low competition and high correlation, and low competition and low correlation. From the measurements of the informed traders¡¦ intraday behavior, we find that in the sample of high competitions of trading, the informed traders trade aggressively to exploit the common private information in the early period; In the middle period, since the common private information has been revealed to the market, the informed traders trade passively to avoid other informed traders knowing his private information; In the later period, the informed trader trade aggressively again to consume their private information before the market close. So, when trading these stocks, uninformed individual investors should avoid entering the market in the early and the later periods because of the high adverse selection cost. Besides, when prior return increases (decreases), the informed traders tend to place buy (sell) orders, indicating the informed traders are momentum traders. Last but not least, we observe in the sample of low competition and low correlation, the foreign investors behave differently in intraday strategy. Given the increasing of prior return, the buy (sell) orders of the foreign investors become passive (aggressive) in the early period, but in the later period, the buy (sell) orders of the foreign investors turn to be more aggressive (passive) with the increasing of prior return. The result may relate to the strategy of proprietary traders. For this reason, when trading these stocks, uninformed individual investors should avoid following the large orders and the momentum strategy in the early period.

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