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1.
孙彤  汪波 《工业工程》2008,11(2):120-124
根据VaR风险度量的原理,借鉴J.P.摩根的信用计量CreditMetries模型中信用等级转移的思想,构建了应收账款回收期内受信企业信用状况转移矩阵,并据此计算出企业营销信用VaR值,为企业信用销售决策提供依据.通过将VaR方法引入企业的风险管理框架中,以期提高企业营销风险管理水平.  相似文献   

2.
本文应用局部多项式拟合方法来估计金融资产价格中隐含的状态价格密度(SPD),在较弱的条件下证明了SPD的估计是相合的。然后基于SPD我们提出了包含经济价值的VaR。从这个意义上讲它比传统的VaR更合理。最后针对Black-Scholes模型进行了数值模拟和失败率检验以评价本文方法的好坏。  相似文献   

3.
介绍了微电网中微电源的控制方法和微电网的综合控制方法。分析了不同情况下微电源的控制方法,指出各种不同控制方法的优缺点。要根据微型电网的各种不同的类型来灵活地确定需要的控制方法。  相似文献   

4.
本文阐述了在玻璃熔窑数值模拟过程中所采用的几种方法,比较了各种方法的优缺点,并且介绍了模拟所采用的各种不同语言。对方法和语言的使用进行了分析,提出了看法。  相似文献   

5.
本文阐述了在玻璃熔窑数值模拟过程中所采用的几种方法,比较了各种方法的优缺点,并且介绍了模拟所采用的各种不同语言。对方法和语言的使用进行了分析,提出了看法。  相似文献   

6.
基于主成分分析的投资组合VaR计算的扰动分析   总被引:1,自引:0,他引:1  
主成分分析法在风险价值(VaR)的计算中可有效地减小问题计算的规模。本文研究了基于主成分分析的投资组合VaR的计算以及由于市场因子的扰动对计算规模的影响,讨论了市场因子存在扰动时主成分个数的变化,给出了不改变主成分个数的扰动界的估计。  相似文献   

7.
面元法的各个环节有不同的数值处理方法,不同的方法计算结果有所不同,通过时各种方法的计算结果进行比较,得到适合螺旋桨计算的数值处理方法。用面元法时吊舱螺旋桨的水动力性能进行了计算,得到了吊舱推进器的敞水曲线和轴承力。  相似文献   

8.
本文对国内外用几种碳化物颗粒增强钢铁基复合材料研究进展进行了综述,比较了不同性能的碳化物颗粒制备方法和应用领域的不同,分析了各种制备方法的特点,并指出存在的问题及今后的发展趋势。  相似文献   

9.
车牌字符识别技术   总被引:3,自引:1,他引:2  
本文分析了车牌字符识别的技术要点,对照了各种不同的解决方法,最后指出了分级分类技术是保证车牌识别快速性和准确性的良好方法。  相似文献   

10.
灌装机灌装时间的计算研究   总被引:2,自引:1,他引:1  
液料的灌装根据灌装与定量方法的不同有多种情况,讨论和分析了各种情况下灌装时间的计算方法,给出了程序框图,编制了简洁实用的设计计算程序。  相似文献   

11.
A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.  相似文献   

12.
Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……  相似文献   

13.
The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……  相似文献   

14.
Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.  相似文献   

15.
We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.  相似文献   

16.
Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.  相似文献   

17.
ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.  相似文献   

18.
Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.  相似文献   

19.
As demands about environment protection are growing up, dry cutting technology is getting more and more concerns from all over the world. Main works performed here are study on dry cutting performances and wear mechanisms of M2high-speed steel (HSS) twist drills with CrAlTiN multicomponent coatings, which was deposited using magnetron sputter ion plating system, in drilling 45 and 30CrMnSiA steel, and their comparisons to those in drilling the same steel but using monolayer CrN and commercial TiN coated drills. Drilling performances of drills are evaluated mainly through the measurements of width on outer corner flank land and the cutting forces. Results show that performances of CrAlTiN coated drills are better than those of monolayer CrN and TiN coated drills. In drilling 45 and 30CrMnSiA steel, the average tool life of the CrAlTiN coated drills are 17.2 and 11.8 times higher than those of the uncoated drills. Observing wear of the drill with scanning electronic microscope, results show that there is no crack or spallation of the CrAlTiN coatings in wear zones. Main mechanism of the wear here is adhesion.  相似文献   

20.
TiO2 ceramic coatings with thickness of 20 μm were formed on the surface of pure titanium by micro-plasma oxidation. Their micro-structures were investigated by by using X-ray diffraction and their surface images were detected by using scan electronic microscope. There were three kinds of TiO2 coatings, pure anatase type TiO2 phase, mixed phases consisted of rutile type TiO2 phase and anatase type TiO2 phase, pure rutile type TiO2 phase. The coating surface with the pure anatase type TiO2 phase is rough, while the coating surface with the pure rutile type TiO2phase is smooth. The upper coating surface with the mixed type TiO2 phases is anatase type TiO2 structure and the subsurface of the TiO2 coating is rutile type TiO2structure.  相似文献   

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