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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.
261

The reproduction and survivorship of Formosan macaques (Macaca cyclopis) at Mt. Longevity

Lin, Jin-fu 02 August 2007 (has links)
This study investigated the reproduction and survival of Formosan macaques (Macaca cyclopis). Data on birth and death of Formosan macaques at Mt. Longevity were collected from 1996 till 2006. The birth of Formosan macaques peaked from April to June (94.4%). The sex ratio of 604 infants at birth was 1:1.2 (female to male), which was not significantly different from 1:1. The death of less than one-month-old infants accounted for 22.2% of all infant death. Infant mortality (less than 1 years old) was very high (35.2%) and no sexual difference was found (p > 0.05). Mortality of males equal or older than 6 years old (16.8-33.3%) were higher than those of females (p < 0.05). In primiparous females, most females (57.6%) gave birth at four years old. The average interbirth intervals of females after infant death within the first 3 months was 0.96 years (¡Ó 0.07, n = 23) which was significantly shorter than that after the successful rearing infants (1.02 years ¡Ó 0.09, n = 185, p < 0.05). Maternal ranks, age, infant sex ratio and troop size had no significant effect on the interbirth intervals (p > 0.05). The average interbirth intervals of high-ranking females (1.03 years) were similar to those from middle- (1.10 years) and low-ranking females (1.01 years). The average interbirth intervals after daughters were slightly longer than those after sons (1.02 and 1.01 years, prospectively). Interbirth intervals among small-sized troops (0.97 years) was slightly shorter than those from large- (1.02 years) and middle-sized troops (1.00 years). The birth rates of high- and middle-ranking females (66.3% and 68.0%, prospectively) were significantly higher than that of low-ranking females (45.6%, p < 0.05). Maternal rank and age had no significant effect on male infant ratio (p > 0.05). However, male infant ratio of high-ranking and young-aged females (76.2%) was 1.3-1.6 times of high-ranking, middle- and old-aged females, 1.5-1.7 times of middle-, low-ranking and young-aged females. Male infant ratio of middle troop size and high-ranking females (66.7%) was 1.2-1.4 times of large- and small-sized troops; 1.4-1.5 times of middle troop size and middle- and low-ranking females.
262

Antiretroviral Regimens in HIV-Infected Adults Receiving Medical Care in the United States: Medical Monitoring Project, 2009

Tie, Yunfeng 19 April 2013 (has links)
Effective antiretroviral therapy (ART) is essential for viral suppression (VS) in HIV-infected patients. However, there is a lack of nationally representative data on types of ART regimens used and their impact on VS. This thesis used self-reported interview and abstracted medical record from 2009 Medical Monitoring Project (MMP) to study ART regimen type and related health outcomes. Results showed that 88.6% of HIV-infected adults in care was prescribed ART, and about half took regimens designated as ‘preferred’ according to U.S ART guidelines. Among MMP participants prescribed ART, 62.7% achieved durable VS, 77.8% achieved recent VS, 83.5% were 100% dose-adherent, and 17.1% reported side effects. Multivariate regression analyses revealed that although ART was critical for VS, there were minor differences in health outcomes among the major ART classes in the U.S. ART guidelines or six most-commonly used regimens. This study could be potentially useful for future strategic planning of HIV care.
263

Ranking line-depth ratios for determining relative star temperatures in dwarfs

Edstam, Louise January 2013 (has links)
The central line-depths of absorption lines depend upon stellar temperature. By dividing the central line-depth of such a line with a central line-depth independent of temperature, a thermometer of relative star temperatures is obtained in the form of a line-depth ratio (LDR), once it is related to an effective temperature scale. Such thermometers are known to give precise results which is why the method is pursued. The purpose of this work is to rank LDRs according to a set of criteria to find the most suitable ratio to measure temperature. This is done based on a set of LDRs measured for a large sample of dwarf stars with known effective temperature, atmospheric pressure and chemical composition. Numerous LDRs are eliminated because their temperature dependence are limited to a short temperature interval. Further LDRs are eliminated due to dependence on the atmospheric pressure and chemical composition of the LDR. The remaining LDRs are ranked based on the strength of temperature dependence, the fit of the representative polynomial to the data points and the number of data points available. The best ranked LDR provides a temperature resolution smaller than 10 K over a temperature interval of 4500-6250 K, assuming an uncertainty in LDR of 0.01.
264

Evaluating and improving collection tree protocol in mobile wireless sensor network

Sharma, Dixit 01 July 2011 (has links)
There has been growing interest in the Mobile WSN applications where mobility is the fundamental characteristic of the sensor nodes. Mobility poses many challenges to the routing protocols used in such applications. In this thesis we evaluate the performance of Collection Tree Protocol as applied in mobile WSN scenarios. The simulation study shows CTP performs poorly in mobile scenario because of the frequent tree re-generation resulting from node movements. We compare Collection Tree Protocol with reactive ad hoc network routing protocols. The simulation results show that collection tree protocol performs better than reactive MANET protocols in terms of data delivery ratio and control overhead under low traffic rates. The end-to-end delay obtained in case of reactive protocols is also higher compared to that obtained when using CTP, which is due to their route discovery process. This thesis presents an improved data collection protocol Fixed Node Aided CTP based on the analysis of CTP. The protocol introduces the concept of fixed aided routing into CTP. It is shown that our enhanced CTP outperforms CTP in terms of data delivery ratio and control overhead chosen as performance metrics. / UOIT
265

Pancreatic α- and β-Cell Function and Metabolic Changes during Oral L-Alanine and Glucose Administration: Comparative Studies between Normal, Diabetic and Cirrhotic Subjects

SAKAMOTO, NOBUO, TAMAGAWA, TATSUO, KAKUTA, HIRONOBU, NOMURA, TAKAHIDE, KUNIEDA, TAKEHIDE, SHINODA, HIROSHI, OHARA, KIYOJI, HOTTA, NIGISHI, HATTORI, TADAKAZU 03 1900 (has links)
No description available.
266

Hybrid DWT-DCT algorithm for image and video compression applications

Shrestha, Suchitra 23 February 2011
Digital image and video in their raw form require an enormous amount of storage capacity. Considering the important role played by digital imaging and video, it is necessary to develop a system that produces high degree of compression while preserving critical image/video information. There are various transformation techniques used for data compression. Discrete Cosine Transform (DCT) and Discrete Wavelet Transform (DWT) are the most commonly used transformation. DCT has high energy compaction property and requires less computational resources. On the other hand, DWT is multiresolution transformation.<p> In this work, we propose a hybrid DWT-DCT algorithm for image compression and reconstruction taking benefit from the advantages of both algorithms. The algorithm performs the Discrete Cosine Transform (DCT) on the Discrete Wavelet Transform (DWT) coefficients. Simulations have been conducted on several natural, benchmark, medical and endoscopic images. Several QCIF, high definition, and endoscopic videos have also been used to demonstrate the advantage of the proposed scheme.<p> The simulation results show that the proposed hybrid DWT-DCT algorithm performs much better than the standalone JPEG-based DCT, DWT, and WHT algorithms in terms of peak signal to noise ratio (PSNR), as well as visual perception at higher compression ratio. The new scheme reduces false contouring and blocking artifacts significantly. The rate distortion analysis shows that for a fixed level of distortion, the number of bits required to transmit the hybrid coefficients would be less than those required for other schemes Furthermore, the proposed algorithm is also compared with the some existing hybrid algorithms. The comparison results show that, the proposed hybrid algorithm has better performance and reconstruction quality. The proposed scheme is intended to be used as the image/video compressor engine in imaging and video applications.
267

Intellektuellt kapital - En svårfångad värdeskapare

Svensson, Tobias, Björkeroth, Didrik January 2013 (has links)
Intellektuellt kapital anses av många vara en av de största drivande faktorerna till företags framgång och i litteraturen värderas den ofta som skillnaden mellan ett företags marknadsvärde och dess bokförda värde. Market-to-book ratio är det relativa måttet som beskriver denna skillnad och gör det möjligt att jämföra detta värde med andra företag. Målet med denna uppsats är att undersöka hur företag redogör för sitt intellektuella kapital och utreda hur detta reflekteras i företags market-to-book ratio. Frågeställningarna som besvaras är huruvida det finns något samband mellan ett företags market-to-book ratio och dess redogörelser för intellektuellt kapital i dess årsredovisningar och om det finns något samband mellan dessa redogörelser och förändringar i market-to-book ratio. För att mäta redogörelser för intellektuellt kapital gjordes innehållsanalyser. Totalt undersöktes 60 företags årsredovisningar på Stockholmsbörsens Large- och Mid Cap. Resultatet tyder på att samband mellan företags market-to-book ratio och dess redogörelser för intellektuellt kapital saknas, undersökningen fann inte heller något samband mellan redogörelser för intellektuellt kapital och förändringar i market-to-book ratio.
268

Experimental Investigation of Film Cooling Effectiveness on Gas Turbine Blades

Li, Shiou-Jiuan 14 March 2013 (has links)
High turbine inlet temperature becomes necessary for increasing thermal efficiency of modern gas turbines. To prevent failure of turbine components, advance cooling technologies have been applied to different portions of turbine blades. The detailed film cooling effectiveness distributions along a rotor blade has been studied under combined effects of upstream trailing edge unsteady wake with coolant ejection by the pressure sensitive paint (PSP). The experiment is conducted in a low speed wind tunnel with a five blade linear cascade and exit Reynolds number is 370,000. The density ratios for both blade and trailing edge coolant ejection range from 1.5 to 2.0. Blade blowing ratios are 0.5 and 1.0 on suction surface and 1.0 and 2.0 on pressure surface. Trailing edge jet blowing ratio and Strouhal number are 1.0 and 0.12, respectively. Results show the unsteady wake reduces overall effectiveness. However, the unsteady wake with trailing edge coolant ejection enhances overall effectiveness. Results also show that the overall effectiveness increases by using heavier coolant for ejection and blade film cooling. Leading edge film cooling has been investigated using PSP. There are two test models: seven and three-row of film holes for simulating vane and blade, respectively. Four film holes’ configurations are used for both models: radial angle cylindrical holes, compound angle cylindrical holes, radial angle shaped holes, and compound angle shaped holes. Density ratios are 1.0 to 2.0 while blowing ratios are 0.5 to 1.5. Experiments were conducted in a low speed wind tunnel with Reynolds number 100,900. The turbulence intensity near test model is about 7%. The results show the shaped holes have overall higher effectiveness than cylindrical holes for both designs. As increasing density ratio, density effect on shaped holes becomes evident. Radial angle holes perform better than compound angle holes as increasing blowing and density ratios. Increasing density ratio generally increases overall effectiveness for all configurations and blowing ratios. One exception occurs for compound angle and radial angle shaped hole of three-row design at lower blowing ratio. Effectiveness along stagnation row reduces as increasing density ratio due to coolant jet with insufficient momentum caused by heavier density coolant, shaped hole, and stagnation row.
269

Subset selection based on likelihood from uniform and related populations

Chotai, Jayanti January 1979 (has links)
Let π1,  π2, ... π be k (&gt;_2) populations. Let  πi (i = 1, 2, ..., k) be characterized by the uniform distributionon (ai, bi), where exactly one of ai and bi is unknown. With unequal sample sizes, suppose that we wish to select arandom-size subset of the populations containing the one withthe smallest value of 0i = bi - ai. Rule Ri selects πi iff a likelihood-based k-dimensional confidence region for the unknown (01,..., 0k) contains at least one point having 0i as its smallest component. A second rule, R, is derived through a likelihood ratio and is equivalent to that of Barr and Rizvi (1966) when the sample sizes are equal. Numerical comparisons are made. The results apply to the larger class of densities g(z; 0i) = M(z)Q(0i) iff a(0i) &lt; z &lt; b(0i). Extensions to the cases when both ai and bi are unknown and when 0max is of interest are i i indicated. / digitalisering@umu
270

Subset selection based on likelihood ratios : the normal means case

Chotai, Jayanti January 1979 (has links)
Let π1, ..., πk be k(&gt;_2) populations such that πi, i = 1, 2, ..., k, is characterized by the normal distribution with unknown mean and ui variance aio2 , where ai is known and o2 may be unknown. Suppose that on the basis of independent samples of size ni from π (i=1,2,...,k), we are interested in selecting a random-size subset of the given populations which hopefully contains the population with the largest mean.Based on likelihood ratios, several new procedures for this problem are derived in this report. Some of these procedures are compared with the classical procedure of Gupta (1956,1965) and are shown to be better in certain respects. / <p>Ny rev. utg.</p><p>This is a slightly revised version of Statistical Research Report No. 1978-6.</p> / digitalisering@umu

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