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61.
When a heterogeneous elastic material is represented by an effective homogeneous elastic solid, average stress and strain fields are used. The meaning of the J-integral in the effective homogeneous solid is investigated. A periodically layered medium is considered. The relation between the J-integrals in the original layered medium and the effective medium is derived. 相似文献
62.
An alternative approach is presented in this article for the calculation of the activity of FeO, Fe2O3, and the other component in ternary oxide slags when the redox behavior of iron oxides is known. The approach avoids the
use of the “tangent intercepts” to the iso-oxygen activity curves as required in Schuhmann's method. Favorable comparisons
were obtained for the systems of FeO-Fe2O3-CaO and FeO-Fe2O3-SiO2 between the isoactivity curves derived using this method and those established in previous work using Schuhmann's method.
Direct calculation of the free energy of mixing from the redox data is also possible. An example is given for the FeO-Fe2O2-CaO system. 相似文献
63.
Kwang Soo Lee In Soo Park & Dong Sun Lee 《International Journal of Food Science & Technology》1996,31(1):7-13
The aim of this study was to design a modified atmosphere package for a mixed vegetable salad consisting of 75 g of cut carrot, 55 g of cut cucumber, 20 g of sliced garlic and 50 g of whole green pepper. Respiration data of all the components were combined with film permeability data to predict package atmospheres and design optimal packages for experimental testing for improved shelf-life of the produce. The optimal package avoided minimum O2 and maximum CO2 tolerance limits, and chilling injury temperatures for any component. A pouch form package made of 27 mm low density polyethylene developed a modified atmosphere of 2.0–2.1% O2 and 5.5–5.7% CO2 , which was beneficial for all components and provided better quality retention than other test packages. 相似文献
64.
机械化栽培甜菜平均单产33.18吨/公顷,比人工栽培生产田提高52.03%;平均含糖15.5度,比人工栽培生产田提高1.09度;平均技术效果138.2元/公顷;经济效果1588.8元/公顷;创造社会经济效益24.47万元。 相似文献
65.
文章对非标准工况下的空分设备增产氩措施进行了研究。以宝钢6#60000m3/h空分设备为例,通过设计型算法和校核型算法,建立了空分设备精馏的数学模型,通过改变数学模型的参数,分析了在非标准工况下精馏塔内的组分浓度分布,并提出了优化后的操作方案和操作参数,实施后提高了空分设备的氩提取率,取得了显著的经济效益。 相似文献
66.
67.
Tzu-Ming Liu Yin-Chieh Huang Gia-Wei Chern Kung-Hsuan Lin Yu-Chueh Hung Chih-Jie Lee Chi-Kuang Sun 《Quantum Electronics, IEEE Journal of》2002,38(11):1529-1535
We present a method to obtain complete information of femtosecond pulses. By measuring triple-optical autocorrelation directly with third-harmonic generation, without spectral information, a temporal pulse shape can be obtained by analytical calculation without direction-of-time ambiguity. Combining the resulting optical pulse shape with its corresponding optical spectrum, the exact phase and color variations in time can all be recovered with a Gerchberg-Saxton algorithm through an iterative calculation with an O(n) complexity. 相似文献
68.
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70.
Public participation is essential in each step of the nuclear-related decision-making process. Recently, the electronic systems using the Internet have become quite popular, and have emerged as a good medium for communicating with the public. In this study, a comprehensive utilization of electronic public participation was used to analyze public opinion on a given nuclear-related decision-making process. The degree of deliberation and meditation of the public participating in an electronic poll survey was evaluated, and the decision-making factors representing the personal characteristics of the poll respondents such as age, income, education, residence, degree of knowledge and concern were carefully incorporated when preparing the poll-survey questionnaire for its evaluation. Fuzzy analysis was used to assess and aggregate the responses to each decision-making factor. As a case study, this procedure was used to analyzing public opinion on the location of a low-level radioactive waste disposal facility on the campus of Seoul National University. The results show that there is a tendency of respondents who are on the negative side of the argument to be more deliberate and meditative in their decision-making process than those on the positive side. Knowledge and residence were found to be important decision-making factors. 相似文献