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1.
企业试图完成数字化转型,这是在竞争中谋求发展的必经之路。文章率先进行数字化转型特征、策略的概念分析,而后总结以此为背景的能力模型、企业管理能力与技术能力,最终以某公司案例完成体系构建与应用的阐述。  相似文献   
2.
Previous studies reported coastal trapped waves (CTWs) in the Caspian Sea (CS). This study deals with the generation mechanisms, the temporal and spatial variability of CTWs in this area, and their transformations during propagation from the origin to the destination using recent measurements and high-resolution numerical simulations. CTWs are observed at all stations with periods of 2–6 days after northerly storms. The Absheron Peninsula, old Sefidrud delta, and Nur coasts were identified as the CTWs prone regions. The generation of CTWs in these locations was confirmed using numerical experiments. The propagation away from the generating location of CTWs was analyzed using a representative real wind storm. In the west part of the CS, the generation mechanism of CTWs is mainly similar to the barotropic Kelvin waves; in contrast, it is similar to the continental shelf waves in the southern shelves. The results can be used to study the contribution of generated CTWs to the transport of sediment and biological materials in all large lakes.  相似文献   
3.
赵元  张丽丽 《机械制造》2020,58(2):77-79
为适应快速多变的市场需求,制造企业需要设计并应用柔性夹具。介绍了柔性夹具的发展及特点,给出了柔性夹具的设计依据,并从零件结构及工艺、组成元件确定、强度与精度保证等方面分析了柔性夹具的设计方法。  相似文献   
4.
张骄  李宇杰  王璐  马亮  李彬 《机械制造》2020,58(3):33-35,38
有轨电车车载储能系统是当前的业内热点。对有轨电车车载储能系统进行了研究,分析了有轨电车车载储能系统的容量配置、拓扑结构选择,论述了有轨电车车载储能系统的能量管理策略,并介绍了有轨电车车载储能系统的应用情况。  相似文献   
5.
Four hydrocarbon-base gasolines (BG) were formulated from the local refinery streams; isomerate, reformate, and light naphtha. The formulations were enriched in reformate. Each of these BG formulations was blended with 10 vol% of anhydrous ethanol. From ASTM-D86 distillation data, eight distillation curves were constructed and the trend line equations of these distillation curves were developed. Also, the area under each distillation curve (AUDC) was calculated through calculus definite integration technique. Subsequently, the area due to azeotrope formation (ADAF) for each BG-ethanol blend was estimated. In this paper, the influence of increasing reformate proportions on the created positive azeotrope, was studied. Also the influence of increasing reformate proportions on vapor pressure, Temperature for the vapor-liquid ratio of 20, T50 and octane number was studied. The results show that the R2 values of the distillation curve equations prove the reliability of the fits. Also, increasing reformate proportion in the fuel blend improves the octane number while increasing reformate proportion decreases the volatility of the fuel formulation.  相似文献   
6.
In1986 the Dutch national fuel cell program started. Fuel cells were developed under the paradigm of replacing conventional technology. Coal-fired power plants were to be replaced by large-scale MCFC power plants fuelled by hydrogen in a full-scale future hydrogen economy. With today's knowledge we will reflect on these and other ideas with respect to high temperature fuel cell development including the choice for the type of high temperature fuel cell. It is explained that based on thermodynamics proton conducting fuel cells would have been a better choice and the direct carbon fuel cell even more so, with electrochemical gasification of carbon as the ultimate step. The specific characteristics of fuel cells and multisource multiproduct systems were not considered, whereas we understand now that these can provide huge driving forces for the implementation of fuel cells compared to just replacing conventional combined heat and power production technology.  相似文献   
7.
Emotion word questionnaires remain dominant in food-related emotion research despite acknowledged limitations. Emoji questionnaires can overcome some of these limitations but are not yet regarded as a strong alternative to emotion word questionnaires. We believe they have the potential to earn this right and use this invited opinion piece to explain why. Following a brief introduction about emoji, advantages of emoji questionnaires are summarised: – enhanced ecological validity, familiarity and cross-culturally shared meanings. We then address concerns that hinder uptake of emoji questionnaires, including emoji meanings/interpretations, appropriateness for older consumers and ability to represent emotional arousal (activation to deactivation). Finally, we offer suggestions for how to accelerate the uptake of emoji questionnaires in sensory and consumer science, which include: i) more applied studies using emoji questionnaires, ii) establishing emoji meanings in the context of eating of drinking, iii) adopting open-ended question formats, iv) comparing emoji and emotion word questionnaires, and v) establishing guidelines for emoji questionnaires. An important spill-over benefit of research to develop emoji questionnaires is that it exposes the lack of similar research for emotion word questionnaires. We encourage colleagues in the field to engage in the task of conducting needed methodological research on emoji and emotion words alike.  相似文献   
8.
文章中主要采用有机溶剂萃取法(OSE)对高浓度石油污染土壤进行修复,经过精馏操作,有效回收原油,建立脱附等温曲线,研究了石油污染物在土壤-有机溶剂两相间的迁移规律。  相似文献   
9.
绩效考核一直是公益型科研院所管理领域的重点和难点。本文以公益型矿业科研院所为研究对象,系统地梳理绩效考核政策的历史沿革,分析国有科研院所“课题组承包制”绩效评价方法,总结“课题组承包制”绩效考核体系的优缺点;探索“以项目为中心”绩效考核体系,从考核基本原则、指标设计、评定方法与标准以及考核组织与实施方法等四个维度建立公益型矿业科研院所绩效考核评价方法;最后,提出了未来企业绩效考核机制的改进建议。为类似的矿业领域科研院所的人力资源管理模式提供了有益参考和借鉴。  相似文献   
10.
分析了二级剪叉式液压升降机的三种主要布置方式,以及液压缸倾斜布置时的三种液压缸安装位置方案。对于其中的一种方案,应用虚位移原理计算求解液压缸推力,并以液压缸推力最小为目标建立优化设计数学模型,通过MATLAB软件得到液压缸推力最小时的液压缸安装位置。通过研究液压缸布置方式,提高了二级剪叉式液压升降机的设计效率和传动质量。  相似文献   
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