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101.
Rekha Kengeri Cheryl D. Seals Hope D. Harley Himabindu P. Reddy Edward A. Fox 《International Journal on Digital Libraries》1999,2(2-3):157-169
If digital libraries are to be used effectively, their user interfaces should be tested and enhanced. We observed 48 participants
as they worked with the following digital libraries: ACM, IEEE-CS, NCSTRL, and NDLTD. We discuss how the features of these
digital libraries influence the subjects’ efforts to perform search and retrieval tasks. Data analysis indicates that the
IEEE-CS digital library was rated the best overall and NDLTD had the best search time. We present user recommendations and
propose a taxonomy of features that we believe are essential for the design of future digital libraries. Noteworthy is the
observation that users’ judgements on the importance of different features varied widely between the beginning and end of
their test sessions.
Received: 15 December 1997 / Revised: June 1999 相似文献
102.
Manish M Paradkar Rekha S Singhal Pushpa R Kulkarni 《Journal of the science of food and agriculture》2003,83(7):727-730
Excessive consumption of Lathyrus sativus leads to crippling, irreversible paralysis of both lower limbs, mainly in males. This is attributed to the presence of a non‐protein amino acid, β‐N‐oxalyl‐L ‐2,3‐diaminopropionic acid or β‐N‐oxalylamino‐L ‐alanine. Using a thin layer chromatography method developed in our laboratory, adulteration of chickpea and red gram with L sativus in pressure‐cooked batters could be detected at levels of 100 and 200 g kg?1 respectively. When processed as a curried liquid dal, L sativus could be detected at 200 g kg?1 in chickpea and 100 g kg?1 in red gram. Processing into fried bhajiyas resulted in a detection limit of 200 g kg?1 in both red gram and chickpea. © 2003 Society of Chemical Industry 相似文献
103.
Manish M Paradkar Rekha S Singhal Pushpa R Kulkarni 《International Journal of Dairy Technology》2001,54(1):36-37
The flow behaviour of cow milk, synthetic milk and their blends was evaluated with a Haake rheometer. Changes in flow behaviour are thought to be due to detergent, an important constituent of synthetic milk, which emulsifies the vegetable fat in the aqueous phase. The results are of value in detecting very low levels (1–10%) of synthetic milk in cow milk. 相似文献
104.
Rohit Arora Deepika Sharma Rakesh Kumar Bikram Singh Adarsh P. Vig Saroj Arora 《Journal of food science》2014,79(10):C1964-C1969
Glucosinolates and their hydrolytic products form an important class of plant secondary metabolites involved in various plant defense‐linked mechanisms. The successful isolation of particular glucosinolate hydrolytic products is limited by a number of factors like understanding the parent glucosinolate moiety, solubility, and stability under different drying conditions. The extraction protocols currently available were modified to achieve both an increased yield as well as an increased number of hydrolytic products. Eruca sativa (Mill.) Thell. (called arugula in the U.S.A.), a rich source of varied glucosinolates, was used for the standardization of different extraction protocols. We exploited the volatile nature of the glucosinolates and developed a method that not only enhanced the yield of glucosinolate hydrolytic products, but also reduced undesired compounds. Among all the tested protocols, hydrodistillation using Clevenger apparatus was judged as the best protocol, which was evident from an enhanced yield as well as an increased number of hydrolytic products when compared to the other methods as monitored by gas chromatography‐mass spectrometry. 相似文献
105.
T.S. Uma Maheswari A. Rekha E. Anjan Rao A.C.N. Raghava Char 《Microelectronics Reliability》1993,33(7)
In this paper we study the reliability of an N-cascade system whose stress and strength follow normal and exponential distributions, respectively. In this system we can observe that reliability increases for lower values of strength parameter (λ) and stress parameter (μ). Marginal reliability rate also increases at higher values of λ. Hence we conclude that the addition of components by a cascade system gives a significant improvement. 相似文献
106.
Selection of the treatment method of choice in orthodontics is usually a question of the clinician's personal preference and is generally based on subjective criteria. Orthodontic treatment of malocclusions is unlike treatment of a disease and hence terms such as success and failure are relative and undefined. Ideally, both patients and providers should be able to arrive at treatment decisions that have the greatest potential for optimum outcomes at minimal cost and risks. This article applies the method of decision analysis to demonstrate how policy choices between "one-stage" or "two-stage" treatment of Class II Division 1 malocclusions for children between 11 and 14 years old can be based on objective criteria. A decision tree was designed to yield the value of payoffs, or outcomes, at each of the possible terminal nodes, and the probability of each payoff. Both positive (ie, improvement in malocclusion) and negative (ie, extraction of teeth and long treatment duration) attributes of outcomes were considered, and numerical values, or "utilities," were assigned to each outcome. For this model, one-stage nonextraction treatment yields the highest probability of maximum benefit. Further applications of decision analysis to resolve clinical uncertainties in orthodontics are discussed. 相似文献
107.
Acoustic sensor sensitivity expressed as frequency change per unit of measurand can result in the erroneous conclusion that higher-frequency sensors are superior to lower-frequency ones. It is argued that, when compared on the bases of reproducibility and resolution capability, good low-frequency sensors are superior to good high-frequency ones 相似文献
108.
Microsystem Technologies - In this paper, a printed microstrip-fed monopole antenna for ultra-wideband range applications with multi band-notched functionality is designed and simulated. The... 相似文献
109.
110.
Synthesis and characterization of azo‐based acrylate polymers for use as nonlinear optical materials
In this work, high molecular weight azo polymers were synthesized by incorporating the azo monomer into a base polymer through their reactive functional groups. Copolymers of methyl methacrylate and methacrylic acid (with varying concentrations of carboxylic acid group) were synthesized. These were then reacted with epoxy‐terminated azo molecule by carboxylic acid–epoxy reaction. The functionalized systems show excellent film homogeneity and optical clarity. The series of copolymers were characterized using FTIR, NMR, UV–vis spectrometry, gel permeation chromatography, elemental analysis, thermogravimetric analysis, and differential scanning calorimetry. The polymer films coated on ITO glass slides were poled and their order parameters were calculated to check the stability of oriented dipoles. Temporal stability, checked up to 120 h under ambient conditions, was found to be excellent. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 425–431, 2007 相似文献