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131.
Postevaluation (PE) of an information system is probably the most neglected activity along the system life cycle. However, PE is essential for making improvements to existing systems and generating standard practices for future information system development projects. Based on actual experience, the 12-step procedure described here can help organizations realize both the future and immediate benefits that PE offers. 相似文献
132.
Danguolė Švegždienė Dalia Koryznienė Danguolė Raklevičienė 《Microgravity science and technology》2011,23(2):235-241
In this study, the kinetics of gravity-dependent movement of amyloplasts (statoliths) along root statocytes and hypocotyls
(endodermis cells) has been analyzed and compared in order to testify cytoskeleton involvement in the displacement of statoliths
in cress (Lepidium sativum L.) seedling statocytes. After 32 h of growth at 1 g or under a fast clinorotation (50 rpm), the seedlings were treated for
24 min as follows: exposition to clinorotation or 180° inversion and the action of gravitational force in root tip or hypocotyl
tip direction. Statolith displacement was studied by light microscopy on semi-thin longitudinal sections of hypocotyls and
root caps, measuring the distance between the centre of plastids and morphological cell bottom. Considerable temporal differences
have been determined between the kinetics of the longitudinal motion of amyloplasts in root and hypocotyl statocytes of 1-g
seedlings upon exposition to fast clinorotation and inversion. In statocytes of both organs of seedlings grown under fast
clinorotation, the gravity provoked displacement of statoliths in the direction of its action; however, the displacement was
much faster in hypocotyl than in root statocytes. It has been assumed that the gravity-determined longitudinal transport of
amyloplasts, both in hypocotyl endodermic cells and root statocytes of cress seedlings, is modulated by the cytoskeleton. 相似文献
133.
Schatzow Margaret D.; Kahane Dalia C.; Youniss James 《Canadian Metallurgical Quarterly》1980,16(6):582
Two experiments with a total of 112 children in Grades 3 and 5 investigated imagined vs actual movement and visible vs hidden array. Major findings are as follows: Movement to the new location significantly improved perspective-taking scores but did not improve coordination scores, and with respect to coordination scores, movement resulted in the substitution of one type of egocentric error for another. Results are interpreted to mean that the self is an important referent for calculating spatial transformations. (5 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
134.
Lukas Y Beis Thelma Polyviou Dalia Malkova Yannis P Pitsiladis 《Journal of the International Society of Sports Nutrition》2011,8(1):1-9
Background
No published data is currently available that describes the dietary patterns or physiological profiles of athletes participating on the Kuwaiti national fencing team and its potential impact on health and physical performance. The purpose of this investigation was to: 1) collect baseline data on nutrient intake 2) collect, analyze and report baseline for body composition, plasma lipid and lipoprotein concentrations during the competitive season, 3) compare the results with the international norms, 4) and provide necessary health and nutritional information in order to enhance the athletes' performance and skills.Methods
Fifteen national-class fencers 21.5 ± 2.6 years of age participated in this study. Food intake was measured using a 3-day food record. Body composition was estimated using both the BOD POD and Body Mass Index (BMI). Total blood lipid profiles and maximum oxygen consumption was measured for each of the subjects during the competitive season.Results
The results of the present study showed significant differences in dietary consumption in comparison with the recommended dietary allowances (RDA). The blood lipids profile and body composition (BMI and % body fat) were in normal range in comparison with international norms However, the average VO2 max value was less than the value of the other fencers.Conclusion
Due to the results of the research study, a dietary regimen can be designed that would better enhance athletic performance and minimize any health risks associated with nutrition. Percent body fat and BMI will also be categorized for all players. In addition, the plasma blood tests will help to determine if any of the players have an excessive level of lipids or any blood abnormalities. The outcomes of present study will have a direct impact on the players health and therefore their skills and athletic performance. 相似文献135.
136.
Dalia Das Animesh Maitra 《International Journal of Satellite Communications and Networking》2012,30(1):19-28
A channel model is proposed to predict the time series of Ku band rain attenuation during a rain event at a tropical location. The model is based on considering the Gaussian distribution of the conditional occurrence of rain attenuation with a particular value of the attenuation occurring before. The mean (μ) and standard deviation (σ) for the distribution are modeled with the experimental data. The measured attenuation at a particular time instant is used to obtain μ and σ and to predict the attenuation after certain interval. The channel model has tested well giving the predicted attenuation that agrees with the measured value with a mean error within 15% higher than 1 dB. Validity of the model is also tested with the first‐order and second‐order statistics of attenuation occurrence, on a long‐term basis. The method can also be applied even if attenuation measurements are missing for certain period of time with increased error. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
137.
138.
The absorbance and fluorescence spectra of Nile Red (NR) were examined in a series of nonpolar solvents comprising linear alkanes and a range of poly alpha olefins (PAO). These solvents span a 1000-fold range in viscosity and possess very similar dielectric constants and refractive index properties. A high-energy double peak with vibronic structure is observed in both fluorescence and absorbance spectra, possibly indicating that a locally excited (LE) state is accessed in these solvents. In addition, a red shift in peak position is observed with increasing refractive index; however, it is unaccompanied by any changes in Stokes shift. This shift is attributed to changes in the high-frequency polarizability of the solvent, which is a function of the refractive index. Finally, an increase in quantum yield with viscosity is also observed. 相似文献
139.
Costantino Grana Giuseppe Serra Marco Manfredi Dalia Coppi Rita Cucchiara 《Multimedia Tools and Applications》2016,75(7):3879-3900
In this paper we describe a system for automatically analyzing old documents and creating hyper linking between different epochs, thus opening ancient documents to young people and to make them available on the web with old and current content. We propose a supervised learning approach to segment text and illustration of digitized old documents using a texture feature based on local correlation aimed at detecting the repeating patterns of text regions and differentiate them from pictorial elements. Moreover we present a solution to help the user in finding contemporary content connected to what is automatically extracted from the ancient documents. 相似文献
140.