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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.
91

Generalized Correlations to Estimate Oil Recovery and Pore Volumes Injected in Waterflooding Projects

Espinel Diaz, Arnaldo Leopoldo 2010 December 1900 (has links)
When estimating a waterflood performance and ultimate recovery, practitioners usually prepare a plot of log of water-oil ratio vs. cumulative production or recovery factor and extrapolate the linear section of the curve to a pre-established economic limit of water production. Following this practice, engineers take the risk of overestimating oil production and/or underestimating water production if the economic limit is optimistic. Engineers would be able to avoid that risk if they knew where the linear portion of the curve finishes. We called this linear portion the "straight-line zone" of simply SLZ. In this research, we studied that ―straight-line zone‖ and determined its boundaries (beginning and end) numerically using mathematics rules. We developed a new procedure and empirical correlations to predict oil recovery factor at any water/oil ratio. The approach uses the fundamental concepts of fluid displacement under Buckley-Leverett fractional flow theory, reservoir simulation, and statistical analysis from multivariate linear regression. We used commercial spreadsheet software, the Statistical Analysis Software, a commercial numerical reservoir simulator, and Visual Basic Application software. We determined generalized correlations to determine the beginning, end, slope, and intercept of this line as a function of rock and fluid properties, such as endpoints of relative permeability curves, connate water saturation, residual oil saturation, mobility ratio, and the Dykstra-Parsons coefficient. Characterizing the SLZ allows us to estimate the corresponding recovery factor and pore volumes injected at any water-oil ratio through the length of the SLZ . The SLZ is always present in the plot of log of water-oil ratio vs. cumulative production or recovery factor, and its properties can be predicted. Results were correlated in terms of the Dykstra-Parsons coefficient and mobility ratio. Using our correlations, practitioners can estimate the end of the SLZ without the risk of overestimating reserves and underestimating water production. Our procedure is also a helpful tool for forecasting and diagnosing waterfloods when a detailed reservoir simulation model is not available.
92

Rapid Spatial Distribution Seismic Loss Analysis for Multistory Buildings

Deshmukh, Pankaj Bhagvatrao 2011 May 1900 (has links)
Tall building frames that respond to large seismic ground motions tend to have significant spatial variability of damage over their height, often with a concentration of that damage in the lower stories. In spite of this spatial variability of damage, existing damage and loss models tend to focus on taking the maximum story drift and then assuming the same drift applies over the entire height, damage is then calculated for the building—clearly a conservative approach. A new loss analysis approach is thus recommended that incorporates the effects of spatial distribution of earthquake induced damage to frame buildings. Moreover, the approach aims to discriminate between required repair and replacement damages. Suites of earthquakes and incremental dynamic analysis along with the commercial software SAP2000 are used to establish demands from which story damage and financial losses are computed directly and aggregated for the entire structure. Rigorous and simplified methods are developed that account for spatial distribution of different damage levels arising from individual story drifts.
93

THE STUDY ON THE FACTOR THAT EFFECT THE CAPITAL STRUCTURE UNDER BUSINESS CYCLE - A EMPIRICAL STUDY OF TAIWAN PUBLIC ELECTRONIC INDUSTRY

Chen, Shih-Ming 26 August 2003 (has links)
NONE
94

An simulative study of exchange rate determination model for mergers

Yang, Hsiao-li 20 February 2004 (has links)
none
95

Silicon and Silicon Nitride Prepared by Ratio-frequency magnetron sputtering on Silicon and Glass substrates

Yang, Chi-Chang 06 July 2007 (has links)
Silicon and silicon nitride thin films were growth on Si and glass substrates at room temperature by ratio-frequency (r-f) magnetron sputtering. The electrical characteristics of the silicon nitride films were characterized using I-V and C-V measurement under different growth condition, including r-f power, nitrogen partial pressure, and hydrogen partial pressure. Minimum current leakages for MIS structure as low as 2¡Ñ10 A/cm were obtained at 1 MV/cm electrical field with hysteresis voltage about 2V. The root-mean square surface roughness of the silicon nitride film is less then 1nm. In addition, silicon nitride capacitors with indium-tin-oxide as electrodes were fabricated. Silicon thin films prepared by R.F. magnetron sputtering at room temperature are amorphous. The measurements on the variation of the photo-conductivity were used to characterize the characteristics of the Si film.
96

Debt Service - Income Nexus: A Cointegration Analysis of Indonesia

CHOLIFIHANI, Muhammad 16 September 2008 (has links)
No description available.
97

A study of the sex ratio and fin morphometry of the Thai medaka, Oryzias minutillus, inhabiting suburbs of Bangkok, Thailand

Ngamniyom, Arin, Magtoon, Wichian, Nagahama, Yoshitaka, Sasayama, Yuichi January 2007 (has links)
No description available.
98

A Study of Macroeconomic Variables that Determine Earnings Multiple of Taiwan Stock Market--Empirical Study of Earnings to Price Ratio (E/P)

Lei, Brook 18 July 2002 (has links)
Abstract The study reported here was tring to examine the macroeconomic variables that determine the earnings multiple of the Taiwan stock market. For this study, monthly time-series data were used for each of the variables from 1991 through 2001. We used earnings to price ratio¡]E/P¡^as the dependent variable¡AM1B¡BGDP¡]lag¡^¡Bmarket return¡Bcapital increasing rate¡Blog of 5 years bond yield¡Binflation rate¡Blag of earning growth and market value to GNP ratio¡]MV/GNP¡^as the independent variables to construct a multiple-regression model. And we finded the maraket value to GNP ratio¡]MV/GNP¡^was the most powerful variable of the 5 significant variables. GDP¡]lag¡^was second, capaital incresing rate ranked third. Market return was fourth, and M1B was the fifth most explanatory variable. Both capaital increasing rate¡]supply side¡^and M1B¡]demand side¡^variables were signifinant¡Ameant the Law of Supply ¡® Demand remained unchanged in the Taiwan stock market.
99

The Application of Real Option on BOT Model Capital Investment Decision-Case Study of Tapeng Bay National Scenic Area

Su, Pei-Kuei 18 July 2002 (has links)
none
100

Effects of conventional or low bull to female ratio and utilization of reproductive tract scores in extensively-managed, natural mating breeding groups

Rathmann, Ryan James 25 April 2007 (has links)
The current study involved two experiments which were conducted at the Texas A&M Agricultural Research and Extension Center in Uvalde (semi-arid environment) from 2002 to 2004. In experiment one, Bonsmara bulls (n = 19; 20-24 mo of age) were joined with multiparous, crossbred females (n =586) for 90 d in 2003 and 2004. Bulls were allotted by selected physical traits, seminal traits, social rank, and serving capacity to one of two bull to female ratio (BFR) treatments: Conventional (1:21-1:29; n = 6 pastures) or Low (1:47-1:52; n = 2 pastures) BFR. Pregnancy rate (P = 0.33), calving rate (P = 0.26), and calving date (P = 0.22) did not differ between Conventional and Low BFR treatments. Post-breeding evaluation of bulls in 2002 (n = 16) indicated that social rank, but not seminal traits, was significantly correlated with pre-breeding values (P < 0.05). The current study demonstrates that Low BFR can be utilized in single- and multisire, 90-d breeding pastures of up to 2,090 ha without adversely affecting reproductive performance. In experiment two, yearling, one-half or three-quarter Bonsmara heifers (n = 106; 11-14 mo of age) were palpated per rectum and assigned a reproductive tract score (RTS) immediately prior to the beginning of the breeding season. Reproductive performance was measured in their two subsequent breeding years in order to estimate the value of the RTS system in extensively-managed, natural mating, 90-d breeding season programs. RTS was positively correlated (p < 0.01) with frame score (r = 0.25), age (r = 0.31), weaning weight (r = 0.47), and the weight of the heifer on the day of RTS exam (r = 0.56). The RTS means by dam parity also differed (P < 0.03). A lower (P < 0.01) percentage of females conceived during each of their first two breeding seasons for heifers of RTS 1 and 2 (65.2%) than for heifers of RTS 3, 4, and 5 (91.2%). Females with a RTS of 1 had a lower pregnancy rate over each of their first two breeding seasons, conceived later during their first breeding season, weaned lighter first calves, and remained lighter each year for fall body weight and body condition score than did heifers with RTS of 2 to 5 (P < 0.05). Collectively, the results of the current study indicate that heifers with a RTS of 1 immediately prior to a 90-d breeding season should be culled. Consideration should also be given to eliminating RTS 2 heifers, but further studies will be needed to confirm the potential economic advantage of this practice.

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