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排序方式: 共有689条查询结果,搜索用时 15 毫秒
681.
682.
Li Zhang Chun Tang Yuqing Song Aidong Zhang Murali Ramanathan 《Distributed and Parallel Databases》2003,13(1):73-97
Visualization enables us to find structures, features, patterns, and relationships in a dataset by presenting the data in various graphical forms with possible interactions. A visualization can provide a qualitative overview of large and complex datasets, can summarize data, and can assist in identifying regions of interest and appropriate parameters focused on quantitative analysis. Recently, DNA microarray technology provides a broad snapshot of the state of the cell, by measuring the expression levels of thousands of genes simultaneously. Such information can thus be used to analyze different samples by gene expression profiles. It has already had a significant impact on the field of bioinformatics, requiring innovative techniques to efficiently and effectively extract, analyze, and visualize these fast growing data.In this paper, we present a dynamic interactive visualization environment, VizCluster, and its application on classifyinggene expression data. VizCluster takes advantage of graphical visualization methods to reveal underlining data patterns. It combines the merits of both high dimensional projection scatter-plot and parallel coordinate plot. In its core lies a nonlinear projection which maps the n-dimensional vectors onto two-dimensional points. To preserve the information at different scales and yet reduce the typical problem of parallel coordinate plots being messy caused by overlapping lines, a zip zooming viewing method is proposed. Integrated with other features, VizCluster is developed to give a simple, fast, intuitive, and yet powerful view of the data set. Its primary applications are on the classification of samples and evaluation of gene clusters for microarray datasets. Three gene expression datasets are used to illustrate the approach. We demonstrate that VizCluster approach is promising to be used for analyzing and visualizing microarray data sets and further development is worthwhile. 相似文献
683.
The fundamental knowledge of the porous nature of crosslinked collagen matrix such as tanned leather is an aid to design appropriate chemicals for leather making. It would also help to target a particular area of matrix to improve its uniformity and other functional properties. The purpose of this study is to analyze the variations in pore sizes of chromium crosslinked collagen matrix, chrome tanned leather, from different animal species and different areas of the same species. In this study, chrome tanned leather from goat and sheep were investigated for surface area, pore size, and distribution. Thermoporometry results show that average pore radius of goat leather is around 2–30 nm and that of sheep is 2–20 nm. Nitrogen adsorption result shows that average surface area of goat (8.24 m2/g) leather is higher than sheep (6.73 m2/g), but the average pore diameter of goat (289 nm) is smaller than sheep (385 nm) leather. It has been found that more numbers of smaller pores are present in goat than sheep leather and all the leather samples including goat and sheep obeyed type‐III adsorption isotherm. Capillary flow porometry analysis gives the smallest, largest, and mean‐flow‐diameter of through‐pores. The average size of largest throat pore diameter of sheep (1313 nm) is smaller than that of goat (1385 nm) leather. In general, the pore volume distribution of sheep leather is higher than that of goat leather. Morphological analysis using scanning electron microscopy shows that pore mouth of goat is deeper than that of sheep. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40835. 相似文献
684.
685.
S. Venkatajalapathi K. Ramesh K. R. Murali 《Journal of Materials Science: Materials in Electronics》2014,25(8):3332-3336
AgInS2 films were pulse electrodeposited on tin oxide coated glass substrates at different duty cycles for the first time. The films were single phase with orthorhombic structure. Optical absorption measurements indicated a band gap in the range of 1.90–2.02 eV with decrease of duty cycle. Transmission spectra exhibited interference fringes. Using the envelope method, refractive index was calculated. Optical conductivity was evaluated from the absorption coefficient and refractive index data. Optical data was analyzed by the single-effective oscillator model. 相似文献
686.
Suryanarayanan Murali S. Vignesh Shanmugam G. Arun Prasaad M. Sarath Kumar C. Manoharan S. R. Devadasan R. Murugesh 《The International Journal of Advanced Manufacturing Technology》2014,70(1-4):173-184
This paper reports a research in which a setup was developed to determine the optimal values of ergonomic positional parameters that would mitigate the development of fatigue while performing massage therapy. This setup was based on virtual instrumentation principles and consisted of a sphygmomanometer bulb, an air sac, a pressure sensor, a data acquisition card and a personal computer installed with the Laboratory Virtual Instrumentation Engineers Workbench software (LABView software). The air sac fitted in this setup is equalised with the muscles and other human body parts which a human therapist is required to press while performing massage therapy. After constructing the air sac fatigue monitoring virtual instrumentation setup, 25 participants who were not actually massage therapists were asked to press the air sac to mimic the behaviour of the massage therapists during the time of their works. After drawing necessary data by performing this activity and by entering the data in Minitab 16 software, regression models to specify optimal values of ergonomic positional parameters were developed. These regression models were practically validated by conducting experiments involving five other participants. The method of utilizing these regression models in determining the optimum values of positional parameters that would mitigate fatigue development while performing massage therapy is illustrated by presenting two cases. While concluding, it is suggested to involve actual massage therapists for testing the performance of the fatigue monitoring virtual instrumentation setup developed during the research reported in this paper. 相似文献
687.
The paper investigates whether the Clean Development Mechanism (CDM) under the Kyoto Protocol has played a significant role in the development of rural communities, specifically investigating uptake of small-scale renewable energy projects. The investigation involved an assessment of 500 registered small-scale CDM projects under the Kyoto Protocol in terms of their potential impact on the envisaged sustainable development goals for rural communities. Five case studies from the Indian subcontinent were also examined. 相似文献
688.
Fish gelatin was plasticized with 20% and 25% glycerol (w/w of gelatin) and used to develop edible films by twin-screw extrusion at 110 and 120 °C followed by compression molding at 80 °C. Tensile and moisture barrier properties and glass transition temperature were then measured and compared with solution-cast films. The films extruded at 110 °C and with 25% glycerol had the highest percent elongation at break of 293 ± 27%. The water vapor permeability values of extruded films (the highest value being 2.9 ± 0.2 g mm h−1 cm−2 Pa−1) were higher than those of solution-cast films while the glass transition temperatures (Tg) of the extruded films were generally lower than those of solution-cast films. Films with 25% glycerol that were extruded at 110 °C had the lowest Tg (2.10 ± 0.31 °C). This investigation showed that extrusion processing followed by compression molding is a feasible method to produce fish gelatin films for commercial applications in a wide range of food products. 相似文献
689.
Poshala Vijay Kumar Narsu Sivakumar Pankaj Shukla Putta Prakash Putta Durgaprasad Chekolu Murali Krishna Chakravarthula Siva Krishnam Raju Gottam Viswanatha Reddy 《亚洲传热研究》2023,52(6):4137-4157
This work examines the boundary flow difficulties of the past and the heat transfer properties of Blasius and Sakiadis flows under prescribed concentration flux and prescribed heat flux. The nanofluid is also taken into account in this model, along with impacts from Brownian motion and thermophoresis. The modified system governing partial differential equations is numerically solved by using the R-K method along with the shooting technique. Various values of physical quantities like thermophoresis parameter, Brownian motion parameter, Eckert number, thermal radiation parameter, heat source parameter, and magnetic field parameter along with the were calculated using the temperature, concentration, and velocity profiles. Finally, we demonstrated how the Brownian motion, radiation, and thermophoresis parameters can significantly increase the temperature distributions. The concentration distributions were decelerated with an increase in Brownian motion parameters for both Blasius and Sakiadis cases. 相似文献