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81.
FN Rehman M Audeh ES Abrams PW Hammond M Kenney TC Boles 《Canadian Metallurgical Quarterly》1999,27(2):649-655
A flexible chemistry for solid phase attachment of oligonucleotides is described. Oligonucleotides bearing 5'-terminal acrylamide modifications efficiently co-polymerize with acrylamide monomers to form thermally stable DNA-containing polyacrylamide co-polymers. Co-polymerization attachment is specific for the terminal acrylamide group. Stable probe-containing layers are easily fabricated on supports bearing exposed acrylic groups, including plastic microtiter plates and silanized glass. Attachment can be accomplished using standard polyacrylamide gel recipes and polymerization techniques. Supports having a high surface density of hybridizable oligonucleotide (approximately 200 fmol/mm2) can be produced. 相似文献
82.
Osamu Kitao Ersan Demiralp Tahir Cagin Siddharth Dasgupta Masuhiro Mikami Kazutoshi Tanabe William A. Goddard III 《Computational Materials Science》1999,14(1-4):135-137
Aluminophosphate zeolite is an artificial material which shows strange hydrophilicity. We have been investigating the reason by quantum mechanics, and found that the hydrophilicity of this zeolite depended on the local geometric deformation, and speculated that the site-specific hydrophilicity might be explained by differences in the stiffness of the local deformation determined by the location with the pore structure. In order to test these ideas, we construct a reliable force field based on the new MS-Q approach developed by Demiralp, Cagin, and Goddard. Our force field well reproduces the experimental structure of VPI-5. 相似文献
83.
84.
An optimal resource utilization framework to analyze the impact of end-to-end delay thresholds on the wireless network throughput is developed. In contrast to conventional networks where lumped transmission and queuing delays are used to model the end-to-end delay, the proposed framework models these delay components separately to analyze their relative contribution to the end-to-end delay when stringent delay thresholds are used. A 'log' utility maximization problem is formulated and its distributed implementation using dual decomposition is proposed. Our optimization results show that decreasing the delay threshold leads to larger contribution from the transmission delay to the end-to-end delay. 相似文献
85.
One of the techniques of work study is work measurement employed to ensure the best possible use of human in carrying out a specific activity. Using appropriate measurement procedures, a work standard can be set which will reflect the gross time required by a normal operator working under normal conditions and with normal pace to complete a unit of work satisfactorily. One of the approaches in setting the work standard is based on the statistical analysis of time data. This paper presents a method of establishing work standard by generating statistical control chart using Excell -- an integrated spreadsheet and graphics software for the Apple-Macintosh. 相似文献
86.
Gordon Rugg Malcolm Eva Atiya Mahmood Nazia Rehman Stephanie Andrews & Sarah Davies 《Information Systems Journal》2002,12(3):215-229
Abstract. Eliciting information about organizational culture is an important part of system analysis and design. However, eliciting knowledge of this sort is difficult. Laddering is an established technique that is particularly suitable for eliciting information about goals and for eliciting explanations, which are important issues when investigating organizational culture. This paper describes the method, its strengths and limitations, its use in several case studies and its relation to other elicitation techniques. Recommendations for further work are given. 相似文献
87.
The present study utilizes the radial basis functions technique for the estimation of monthly mean daily values of solar radiation falling on horizontal surfaces and compares its performance with that of the multilayer perceptrons network and a classical regression model. In this work, we use solar radiation data from 41 stations that are spread over the Kingdom of Saudi Arabia. The solar radiation data from 31 locations are used for training the neural networks and the data from the remaining 10 locations are used for testing the estimated values. However, the testing data were not used in the modeling or training of the networks to give an indication of the performance of the system at unknown locations. Results indicate the viability of the radial basis for this kind of problem. 相似文献
88.
Comparison of component method with experimental tests for flush end-plate connections using hot-rolled perwaja steel sections 总被引:1,自引:1,他引:0
A component method has been introduced by Steel Construction Institute to predict the moment resistance of partial strength
connection. The design philosophy is taken directly from Eurocode 3 with strength checks on bolts, welds, and steel which
have been modified to comply with BS 5950-1:2000. The accuracy of the method however needs to be validated with the experimental
tests especially for hot-rolled sections other than typical British Section (BS). Six experimental tests on beam-to-column
connections have been carried out for Flush End-Plate (FEP) connections consisting of variable parameters such as thickness
of end-plate, size and number of bolts, size of columns, and beams. The tests were set-up using local hot-rolled steel sections
known as Perwaja Section (PS) for beams and columns instead of typical British Section (BS). The strength of materials for
end-plate, column and beam sections were tested for tensile strength and used in predicting the moment resistance for component
method. The moment versus rotation of the test results were plotted and compared with the moment resistance derived from component
method. The study concluded that the moment resistance of the tested flush end-plate connections was higher than the predicted
moment resistance from component method which showed good agreement between the two moments. The study also concluded that
the tested FEP connections met the requirements and criteria of partial strength connections. 相似文献
89.
Umer Shafique Jamil Anwar Waheed uz-Zaman Rabia Rehman Muhammad Salman Amara Dar Nadia Jamil 《Journal of Hydro》2012,6(3):221-226
Migration of soluble and suspended materials by directional freezing of aqueous systems has been studied qualitatively. Slow freezing was employed vertically as well as horizontally through solutions and suspensions. In all cases, the impurities (soluble salts as well as suspended materials) were appreciably forced out by dynamic freezing front. The phenomenon worked for concentrating/separating inorganic ions, soluble organic compounds and dyes in synthetic solutions as well as in natural streams. Various analytical techniques were employed to monitor the migrating species through the freezing media. It was found that separation efficiency depends on different factors like rate of cooling, pH and concentration. Model experiments were designed and exercised successfully to employ the technique for treatment of dye-polluted water. 相似文献
90.