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991.
以猕猴桃、苹果、芹菜为原料,对猕猴桃复合营养饮料配方和稳定剂的选择通过正交设计进行了优选试验,同时对该饮料的护色方法和Vc稳定性作了探讨,确定了较为经济可行的猕猴桃复合营养饮料的生产工艺。 相似文献
992.
电动装甲车方波电机制动过程泵升电压抑制新方法 总被引:1,自引:0,他引:1
为了抑制电动装甲车在制动过程中产生的对系统工作不利的高泵升电压,通过对制动过程泵升电压产生机理的分析,得出了泵升电压同PWM占空比之间的函数关系,提出了通过控制PWM占空比来有效抑制泵升电压的数字控制新方法. 该方法可以有效地减小电容值,在一定程度上减小了控制器的体积,提高了控制器的性能价格比. 计算机仿真和实验结果证明了这种数字控制方法的正确性和可行性. 相似文献
993.
Ambrosio Toval Joaquín Nicolás Begoña Moros Fernando García 《Requirements Engineering》2002,6(4):205-219
Information systems security issues have usually been considered only after the system has been developed completely, and
rarely during its design, coding, testing or deployment. However, the advisability of considering security from the very beginning
of the system development has recently begun to be appreciated, and in particular in the system requirements specification
phase. We present a practical method to elicit and specify the system and software requirements, including a repository containing
reusable requirements, a spiral process model, and a set of requirements documents templates. In this paper, this method is
focused on the security of information systems and, thus, the reusable requirements repository contains all the requirements
taken from MAGERIT, the Spanish public administration risk analysis and management method, which conforms to ISO 15408, Common
Criteria Framework. Any information system including these security requirements must therefore pass a risk analysis and management
study performed with MAGERIT. The requirements specification templates are hierarchically structured and are based on IEEE
standards. Finally, we show a case study in a system of our regional administration aimed at managing state subsidies. 相似文献
994.
995.
996.
A. Piñol-Juez A. Iza-Mendia I. Gutiérrez 《Metallurgical and Materials Transactions A》2000,31(6):1671-1677
In the present work, the mechanical properties and the microstructural evolution of a duplex stainless steel in the as-cast
and wrought conditions during deformation under hot-working conditions have been studied. Hot torsion tests, at strain rates
of
= 1 s−1, have been carried out using prepolished samples on which surface parallel scratches have been practiced. The observation
of the surface of the samples shows a large displacement of the scratches produced by two different mechanisms, sliding on
the δ/γ interface, and shearing of the ferrite. The displacements in the as-cast condition have been found to concentrate in a reduced
set of ferrite/austenite interfaces leading to the formation of cracks along them. In the wrought material, the distribution
of the sliding is more homogeneous over all the ferrite/austenite interfaces, and no damage has been produced. These behavioral
differences between both materials have been related in the present work, to the characteristics of the corresponding microstructures,
to the spatial phase distribution, and to the nature of the ferrite/austenite interface, among others. 相似文献
997.
Optical alignment of segmented mirrors to the fluorescence detectors of the Pierre Auger observatory
Cordero-Dávila A Nuñez-Alfonso JM Castro-Ramos J Percino-Zacarias ME 《Applied optics》2000,39(19):3295-3299
Segmented mirrors will be used in the telescopes of the Pierre Auger Fluorescence detector. To align the segments, we have developed four methods in which (a) the image of the stop border, (b) the image of a screen with concentric circles, and (c) the Ronchi pattern are used. In addition to these, we have developed a new method, (d), in which instead of the Ronchi ruling, we have used a circular grid. In this case we obtain a moiré pattern for each segment by means of which the experimental setup is simplified, and the sensitivity of the alignment is improved. 相似文献
998.
Topologies for optical interconnection networks based on the optical transpose interconnection system 总被引:1,自引:0,他引:1
Many results exist in the literature describing technological and theoretical advances in optical network topologies and design. However, an essential effort has yet to be made in linking those results together. We propose a step in this direction by giving optical layouts for several graph-theoretical topologies studied in the literature, using the optical transpose interconnection system (OTIS) architecture. These topologies include the family of partitioned optical passive star (POPS) and stack-Kautz networks as well as a generalization of the Kautz and the de Bruijn digraphs. 相似文献
999.
1000.
Campo MM Santolaria P Sañudo C Lepetit J Olleta JL Panea B Albertí P 《Meat science》2000,55(4):371-378
Forty-two male yearlings were used to assess the influence of breed type and ageing time on beef texture. Samples of the M. longissimus dorsi of four breed types [double muscled (DM), dual purpose (Brown Swiss, BS), fast growth (FG) and unimproved type (UT)] were aged for 1, 3, 7, 10, 14 or 21 days at 4°C and frozen at −18°C until analysed. Cooked samples (to end-point of 70°C) were assessed using a Warner–Bratzler (WB) device. Raw samples were assessed using a compression device in which transverse elongation was prevented. There were no significant differences in WB values of cooked meat due to breed type, but ageing had a significant (P<0.05) on maximum load. Ageing, but not breed type, had a significant effect on the compression values of raw meat at low compression rates (P<0.001). Compression values, of raw samples, at 80% compression differed significantly (P<0.001) between breed types, but were not affected by ageing. Compression values of raw samples, at 80% compression, were affected by breed type, probably because of genotype differences in the contribution of connective tissue. 相似文献