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排序方式: 共有186条查询结果,搜索用时 15 毫秒
1.
Avinash Samvedi Vipul Jain 《Engineering Applications of Artificial Intelligence》2013,26(3):1044-1051
The supply chains today have become vulnerable to frequent disruptions, and with continuing emphasis on efficiency, lacks robustness to deal with them. A part of the solution lies in forecasting the disruption beforehand and the other part in knowing which policies will suit such disrupted conditions best. Accurate and immediate forecasts are a must in a supply chain and hence play a huge role in stabilizing. This study compares the performance of three established forecasting methods (moving average, weighted moving average and exponential smoothing) as well as grey prediction method, during disruptions and stable situations. The experiments are performed in the form of discrete event simulation, on a four stage beer game settings. The results show that moving average and weighted moving average methods become incompetent during disruptions, and are useful only during stable times, when the demand hovers around a predefined mean value. Exponential smoothing and grey method seems to give better results during disruptions and also during stable times in upstream tiers. Grey prediction method in particular is the best method when the disruption frequency is high and also when the disruption impact is gradual rather than sudden. 相似文献
2.
S. G. Deshmukh S. J. Patel K. K. Patel A. K. Panchal Vipul Kheraj 《Journal of Electronic Materials》2017,46(10):5582-5588
For widespread application of thin-film photovoltaic solar cells, synthesis of inexpensive absorber material is essential. In this work, deposition of ternary Cu3BiS3 absorber material, which contains abundant and environmentally benign elements, was carried out on glass substrate. Flowerlike Cu3BiS3 thin films with nanoflakes as building block were formed on glass substrate by chemical bath deposition. These films were annealed at 573 K and 673 K in sulfur ambient for structural improvement. Their structure was characterized using Raman spectroscopy, as well as their surface morphological and optical properties. The x-ray diffraction profile of as-deposited Cu3BiS3 thin film revealed amorphous structure, which transformed to orthorhombic phase after annealing. The Raman spectrum exhibited a characteristic peak at 290 cm?1. Scanning electron microscopy of as-deposited Cu3BiS3 film confirmed formation of nanoflowers with diameter of around 1052 nm. Wettability testing of as-deposited Cu3BiS3 thin film demonstrated hydrophobic nature, which became hydrophilic after annealing. The measured ultraviolet–visible (UV–Vis) absorption spectra of the Cu3BiS3 thin films gave an absorption coefficient of 105 cm?1 and direct optical bandgap of about 1.42 eV after annealing treatment. Based on all these results, such Cu3BiS3 material may have potential applications in the photovoltaic field as an absorber layer. 相似文献
3.
Sharma Narinder Bhatia Sumeet Singh Sharma Vipul Sivia Jagtar Singh 《Wireless Personal Communications》2020,111(3):1977-1997
Wireless Personal Communications - This article presents a microstrip-fed octagonal shaped monopole antenna with dual band notched characteristics for UWB applications. Partial ground plane has... 相似文献
4.
J Pokorny J Davídek V Chocholatá J Pánek H Bulantová W Janitz H Valentová M Vierecklová 《Die Nahrung》1990,34(2):159-169
The reaction of ethyl linoleate with collagen proceeded at 60 degrees C following the first order kinetics but during the hydroperoxide decomposition the rate constant of the first order decomposition was substantially lower than that of the second order decomposition. Contrary to cellulose, collagen catalyzed the hydroperoxide decomposition. The amount of total oxidation products rose rapidly at the stage of rapid hydroperoxide formation, and slowly afterwards. The browning reaction was fasted in the stage of maximum hydroperoxide content, and both ether-insoluble and ether-soluble pigments were formed, the latter low in nitrogen. The amount of lipid oligomers increased mainly in the reaction stage following the hydroperoxide maximum. Soluble collagen was converted into insoluble forms by the reaction with oxidized lipids. Basic amino acids were blocked by reaction with oxidized lipids but the bonds formed became resistant to acid hydrolysis only in the stage following the hydroperoxide maximum. Changes of sensory profiles could be explained by reactions of flavour-active carbonylic oxidation products with protein. 相似文献
5.
Fillers are essential component of printing papers to increase the opacity, brightness, and to improve formation and printing properties. As a very little work has been reported so far on magnesium silicate (talc), the study was conducted with the filler of different particle size for papermaking. The sheets were made in the laboratory with refined mixed hardwood chemical pulp with five grades of talc, ground calcium carbonate (GCC) and precipitated calcium carbonate (PCC) fillers with 15–24% ash level. Apparent density along with tensile, burst, tear index, Z‐direction tensile strength (ZDTS) and bending stiffness index were evaluated for talc filled sheets, and compared with GCC and PCC. Physical strength properties of talc filled sheets were decreased at a faster rate on increasing filler loading in paper and decreasing the particle size of the filler. With same type of filler its particle size determines the physical properties of paper. The postulate was not found to be valid for all the three varieties of fillers viz., talc, PCC and GCC. Shape and geometry of the PCC and GCC fillers determine the individual property. © 2012 Canadian Society for Chemical Engineering 相似文献
6.
Kasper P. Lundquist Dr. Vipul Panchal Prof. Charlotte H. Gotfredsen Prof. Ruth Brenk Prof. Mads H. Clausen 《ChemMedChem》2021,16(17):2588-2603
Rapid development within the fields of both fragment-based drug discovery (FBDD) and medicinal targeting of RNA provides possibilities for combining technologies and methods in novel ways. This review provides an overview of fragment-based screening (FBS) against RNA targets, including a discussion of the most recently used screening and hit validation methods such as NMR spectroscopy, X-ray crystallography, and virtual screening methods. A discussion of fragment library design based on research from small-molecule RNA binders provides an overview on both the currently limited guidelines within RNA-targeting fragment library design, and future possibilities. Finally, future perspectives are provided on screening and hit validation methods not yet used in combination with both fragment screening and RNA targets. 相似文献
7.
Comparison of HPLC and GLC methodologies for determination of glucosinolates using reference material 总被引:1,自引:0,他引:1
The reference material rapeseed of known glucosinolate composition, was analysed by HPLC and GLC and two commercially available
glucosinolates (glucotropaeolin and sinigrin) were used as internal standards. The HPLC method enabled determination of 11
different glucosinolates (as desulphoglucosinolates) that occur in the rapeseed. Only seven glucosinolates (as trimethylsilylated
desulphoglucosinolates) were separated by GLC. The latter method did not allow the determination of methylsulphinylalkyl glucosinolates
(glucoiberin, glucoraphanin and glucoallysin) and did not separate optical isomers of 2-hydroxy-3-butenyl glucosinolate (progoitrin
and epi-progoitrin). Statistical evaluation of data (t-test, F-test) revealed no significant differences between the tested methods at the 95% confidence level. The advantages and disadvantages
of both widely used chromatographic methods are discussed.
Received: 26 May 1997 / Revised version: 11 July 1997 相似文献
8.
Secure and mobile networking 总被引:2,自引:0,他引:2
The IETF Mobile IP protocol is a significant step towards enabling nomadic Internet users. It allows a mobile node to maintain
and use the same IP address even as it changes its point of attachment to the Internet. Mobility implies higher security risks
than static operation. Portable devices may be stolen or their traffic may, at times, pass through links with questionable
security characteristics. Most commercial organizations use some combination of source-filtering routers, sophisticated firewalls,
and private address spaces to protect their network from unauthorized users. The basic Mobile IP protocol fails in the presence
of these mechanisms even for authorized users. This paper describes enhancements that enable Mobile IP operation in such environments,
i.e., they allow a mobile user, out on a public portion of the Internet, to maintain a secure virtual presence within his
firewall-protected office network. This constitutes what we call a Mobile Virtual Private Network (MVPN).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
9.
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