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排序方式: 共有334条查询结果,搜索用时 15 毫秒
31.
电容传感器是电容式电子清纱器的关键部件,本文着重讨论了DQS—8603型清纱器研制中电容传感器的几个问题,以促进我国清纱器的发展。 相似文献
32.
A stochastic model (G-O) for the software failure phenomenon based on a nonhomogeneous Poisson process (NHPP) was suggested by Goel and Okumoto (1979). This model has been widely used but some important work remains undone on estimating the parameters. The authors present a necessary and sufficient condition for the likelihood estimates to be finite, positive, and unique. A modification of the G-O model is suggested. The performance measures and parametric inferences of the new model are discussed. The results of the new model are applied to real software failure data and compared with G-O and Jelinski-Moranda models 相似文献
33.
Legal reasoning involves case analysis in statutory as well as real world perspectives. The impact of real world perspective
on case analysis poses a serious challenge to knowledge engineers for building legal expert systems. A legal expert system
intends to provide intelligent support to legal professionals. The proposed legal predictive system is an attempt to predict
the most probable outcome of a case according to statutory as well as real world knowledge of the legal domain. The system
accepts the current fact situation of a case and analyses it interactively with legal personnel. This work introduces a frame-like
knowledge structure,lattice, with two-dimensional attributes. This paper contains a detailed discussion on artificial intelligence-based case analysis
of theft cases in a real world perspective. 相似文献
34.
Investigations have been carried out with the help of Laplace transforms and supplementary variable techniques for the evaluation of reliability analysis of a three-state multi-component warm standby redundant complex system suffering three types of failures, namely minor, major, and human due to critical human errors incorporating the concept of waiting for repair. 相似文献
35.
Influence of altitudinal variation on the antioxidant potential of tartar buckwheat of Western Himalaya 总被引:1,自引:0,他引:1
Garima Kishore Shashi Ranjan Anjana Pandey Sanjay Gupta 《Food science and biotechnology》2010,19(5):1355-1363
In the present work, the effect of altitudinal variations on the total phenol, flavonoid, and antioxidant potential of seeds
and hull of Tartar buckwheat collected from 15 different locations of Western Himalaya has been investigated. Methanolic and
acetonic extracts of seed and hull powder showed significantly increasing amounts of total polyphenol content, and antioxidant
potential with rising altitude. Methanolic extract of seed and hull powder were found to have significantly greater polyphenol,
and antioxidant potential as compared to acetonic extract. The methanolic seed extract of Inderdhara (3,133 m) showed the
maximum total phenolic content 1,651 μg gallic acid equivalent/50 mg of dry weight. The methanolic seed extract of Inderdhara
showed the maximum antioxidant activity (77.29±1.2%) and antiradical activity (55.5±0.5%) also. The results of this study
exhibited good correlation with total polyphenol and antioxidant potential in all the samples followed by the increasing tendency
towards rising altitude. 相似文献
36.
Manu Kumar Bhagwat Singh Kherawat Prajjal Dey Debanjana Saha Anupama Singh Shashi Kant Bhatia Gajanan Sampatrao Ghodake Avinash Ashok Kadam Hyun-Uk Kim Manorama Sang-Min Chung Mahipal Singh Kesawat 《International journal of molecular sciences》2021,22(14)
PIN-FORMED (PIN) genes play a crucial role in regulating polar auxin distribution in diverse developmental processes, including tropic responses, embryogenesis, tissue differentiation, and organogenesis. However, the role of PIN-mediated auxin transport in various plant species is poorly understood. Currently, no information is available about this gene family in wheat (Triticum aestivum L.). In the present investigation, we identified the PIN gene family in wheat to understand the evolution of PIN-mediated auxin transport and its role in various developmental processes and under different biotic and abiotic stress conditions. In this study, we performed genome-wide analysis of the PIN gene family in common wheat and identified 44 TaPIN genes through a homology search, further characterizing them to understand their structure, function, and distribution across various tissues. Phylogenetic analyses led to the classification of TaPIN genes into seven different groups, providing evidence of an evolutionary relationship with Arabidopsis thaliana and Oryza sativa. A gene exon/intron structure analysis showed a distinct evolutionary path and predicted the possible gene duplication events. Further, the physical and biochemical properties, conserved motifs, chromosomal, subcellular localization, transmembrane domains, and three-dimensional (3D) structure were also examined using various computational approaches. Cis-elements analysis of TaPIN genes showed that TaPIN promoters consist of phytohormone, plant growth and development, and stress-related cis-elements. In addition, expression profile analysis also revealed that the expression patterns of the TaPIN genes were different in different tissues and developmental stages. Several members of the TaPIN family were induced during biotic and abiotic stress. Moreover, the expression patterns of TaPIN genes were verified by qRT-PCR. The qRT-PCR results also show a similar expression with slight variation. Therefore, the outcome of this study provides basic genomic information on the expression of the TaPIN gene family and will pave the way for dissecting the precise role of TaPINs in plant developmental processes and different stress conditions. 相似文献
37.
Swarnkar Rishabh Das Ashish Prasad Shashi Bhushan 《Russian Journal of Non-Ferrous Metals》2021,62(3):333-340
Russian Journal of Non-Ferrous Metals - This paper investigates the effects of brass interlayer on the microstructural and mechanical properties of friction stir welded AA 6082-T6. To analyze the... 相似文献
38.
N. Basavaraju S.C. Prashantha H. Nagabhushana C. Pratapkumar C.R. Ravikumar M.R. Anil Kumar B.S. Surendra T.R. Shashi Shekhar H.B. Premkumar H.P. Nagaswarupa 《Ceramics International》2021,47(7):10370-10380
Series of (1–9 mol %) dysprosium (Dy3+) ions doped MgNb2O6 (MNO) nanophosphors were synthesized by chemical combustion process and their photo luminescent and photocatalytic behaviours were examined. Powder X-ray diffraction (PXRD) reveals the columbite structure and crystal structure parameters were calculated. The average crystallite size was found to be in the range of 20–30 nm as calculated by Scherrer's method. The photoluminescence (PL) of MgNb2O6:Dy3+ (λexc-393 nm) reflects white emission for the prepared samples as confirmed by CIE and CCT. The photocatalytic activities of these nanophosphors were probed for the decolorization of acid red 88 (AR-88) under UV light irradiation. The photocatalyst with MgNb2O6:Dy3+ (5 mol %) showed enhanced activity of 97%, attributed to effective separation of charge carriers. All the above experimental results confirm that, the optimized phosphor is quite useful for WLEDs, solid-state lighting applications and as a photocatalyst. 相似文献
39.
Mobile ad-hoc network is an infrastructure less type of network which does not require any kind of fixed infrastructure. It provides multi-hop communication between the source and destination nodes which are not within the direct range of each other through the intermediate nodes. These intermediate nodes cooperate with other nodes in finding an optimum and shortest route toward the destination. However, in holistic environments, some nodes do not cooperate with other nodes in finding the optimal route towards the destination and intentionally give the false route information of having the shortest path toward the destination with a high destination sequence number in order to attract the traffic toward itself and start dropping of the data packets instead of forwarding it. This type of routing misbehaviour is generally called as black hole attack or full packet dropping attack which is one of the most severe destructive attacks that lead to the network degradation. In this paper, we have proposed a protocol called as Mitigating Black Hole effects through Detection and Prevention (MBDP-AODV) based on a dynamic threshold value of the destination sequence number. In order to validate the efficiency of proposed protocol, the NS-2.35 simulator is used. The simulation results show that proposed protocol performs better as compared with existing one under black hole attack. 相似文献
40.
Wireless Networks - Mobile Ad hoc network (MANET) is a wireless network which is characterized by dynamic network topology, open medium, multi-hop communication etc. in which each device not only... 相似文献