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1.
针对某农机企业装配车间生产效率低下的问题,以玉米机装配线为研究对象,对其构建和优化混流装配线进行了研究。首先计算了玉米机不同型号产品构建混流装配线的综合作业时间,绘制了作业优先顺序图,然后运用启发式算法对该混流装配线的平衡问题进行了分析与优化,最后运用Flexsim仿真软件对混流装配线进行了动态仿真,以此验证了构建的混流装配线的可靠性。通过优化,混流装配线平衡率提升了14.87%以上,装配线瓶颈工时降低了(13.47~19.28)min,生产效率提高了一倍以上。研究结果表明,运用启发式算法可直接得到混流装配线工位数和作业时间,有效解决农机混流装配线平衡优化问题。 相似文献
2.
《Oil and Energy Trends》2021,46(1):29-37
Current data of world oil demand. This includes international bunkers and refinery fuel. Updated on a monthly basis. Current data of oil demand from counties such as Canada, the United States of America, Japan, OECD Europe, Belgium, France, Germany, Italy, Netherlands, Spain, Sweden, the United Kingdom, Australia, Mexico, Republic of Korea, and Turkey. Updated on a monthly basis. Current data for crude oil and refined product stocks in Canada, Chile, Mexico, the United States (Western Hemisphere), France, Germany, Italy, Netherlands, Spain, the United Kingdom and Other Europe (Europe), Japan, Republic of Korea, Other Pacific (Asia‐Pacific), and Total OECD (Table 12.1) Current data for refined product stocks in the OECD Western Hemisphere, OECD Europe, OECD Asia‐Pacific and Total OECD. Products include gasoline, diesel and gasoil, and heavy fuel oil. Updated on a monthly basis (Table 12.2). 相似文献
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4.
《Oil and Energy Trends》2019,44(11):37-45
Current data of world oil demand. This includes international bunkers and refinery fuel. Updated on a monthly basis. Current data of oil demand from counties such as Canada, the United States of America, Japan, OECD Europe, Belgium, France, Germany, Italy, Netherlands, Spain, Sweden, the United Kingdom, Australia, Mexico, Republic of Korea, and Turkey. Updated on a monthly basis. Current data for crude oil and refined product stocks in Canada, Chile, Mexico, the United States (Western Hemisphere), France, Germany, Italy, Netherlands, Spain, the United Kingdom and Other Europe (Europe), Japan, Republic of Korea, Other Pacific (Asia-Pacific), and Total OECD (Table 12.1) Current data for refined product stocks in the OECD Western Hemisphere, OECD Europe, OECD Asia-Pacific and Total OECD. Products include gasoline, diesel and gasoil, and heavy fuel oil. Updated on a monthly basis (Table 12.2). 相似文献
5.
《International Journal of Hydrogen Energy》2019,44(20):10120-10128
Last three decades, costumers and manufacturers of automotive sector have been influenced positively by Hydrogen and fuel cells (FCs). The main goal of automakers can be pointed as minimizing the fuel consumption and exhaust emissions while improving the range limits, energy efficiency and latest technology adaptation. Therewithal, electric assisted propulsion systems added to vehicles and are called as electric vehicles (EVs). For that matter, Battery Electric Vehicles (BEVs) and hydrogen Fuel Cell Electric Vehicles (FCEVs) have become the focus of researchers and producers. In this mini foreseen review, overview of the next quarter century vision of FCEVs are expressed and discussed by the helped of previous researches and with future forecast reports. The introduction part is summarized the general approach and future expectations of FCs in detailed. Technical overview is represented for FCs and FCEVs in terms of current state of technology to foreseen expectancy. Infrastructure analysis and future aspects overview part is also discussed for sector's perspective on FCEVs. The near future perspective of the FCEVs, which is seen as the next step in EVs, is discussed in detail in the next quarter century vision. Authors concluded that, between the 2030s-2050s, hydrogen FCEVs will continue their rising demand scale under the circumstances of decreasing expensive technology; enhanced energy optimization; extended range limits and increasing hydrogen refueling stations. 相似文献
6.
The Military Utility Assessment of Future Technologies (MUAFT) method was developed as a cost-efficient alternative to methods such as NATO's Disruptive Technology Assessment Games, to be used as a part of the Swedish Armed Forces' long-term capability development process. The question addressed in this study is whether MUAFT can be considered to have validity in its context and thus if it has potential to be useful to other small to medium size states. The analysis was based on an operationalization of Clark's framework for science and technology intelligence analysis, combined with a military capability centric view of military utility. MUAFT reports from 2012 to 2018 were reviewed in terms of how they satisfy five key criteria. The study shows that MUAFT provides utility, if used by a suitably composed group of experts, who are aware of the method's limitations. The limitations mainly originate from a lack of explicit support for assessing the impact of forces for change, other than technological forces, on military capability development. The expert group serves as the synthesizing bridge between technology forecasts and military utility assessments. Therefore, comprehensive expertise is needed in various military technology specialisations, in the sponsor's military capabilities and in subjects necessary to master in order to assess other influential societal forces for change. 相似文献
7.
《矿业科学技术学报(英文版)》2019,29(3):429-435
Conventional mining practices do not extract all mineralized rocks due to prevailing economics.Improvement in mineral prices and processing recovery(technology) could potentially make mineralized waste rocks profitable. A well-integrated mining strategy that focuses on both economic and physical resource depletion is vital to the management of non-renewable mineral resources. In this paper, a conceptual framework that maximizes the benefits of mining and processing mineralized waste rocks as future resource is proposed. Governmental policy and technical reforms that ensure mining companies incorporate the proposed mineralized waste rocks management framework in their long-term strategic mine plans have been recommended. 相似文献
8.
New technologies offer employers the ability to replace tasks done by human labour with those done by machines. There are challenges for both employers and employees, as employers look for strategies for the implementation of automation technologies and employees may have concerns about their employment being threatened by automation technologies. In this research, we analyse data of over 500 Bulgarians to learn about how they perceive the automation of their jobs. The analysis finds that there are segments of the population defined by demographics and attitudes that are more fearful of the automation of their jobs than others. Additionally, we see that attitudes towards the dehumanizing effects of automation, peer-pressure, job automatability, and a person's self-perception of professionalism are the main drivers of the fear of automation. Finally, the paper evaluates respondents' attitudes towards various individual, corporate and social solutions to automation fears. 相似文献
9.
Wanyang Li Xuefeng Yang Shouren Wang Jupeng Xiao Qimin Hou 《Ceramics International》2021,47(8):10442-10463
This article mainly discusses the research status and development trends of ceramics for automotive disc-brakes. According to the ceramic disc-brakes, various properties and characteristics, including fracture toughness, strength, compactness, corrosion resistance, wear resistance, micro-morphology, and thermal stabilities are analyzed. In the field of disc-brakes research, the research directions of the ceramics, including high-temperature performance, bionic structure, layered structure, porous structure, eutectic performance, superhard structure, and machinability are analyzed. The analysis of ceramics is expected to find disc-brake materials in line with the future development trends. 相似文献
10.
《Oil and Energy Trends》2020,45(1):35-43
Current data of world oil demand. This includes international bunkers and refinery fuel. Updated on a monthly basis. Current data of oil demand from counties such as Canada, the United States of America, Japan, OECD Europe, Belgium, France, Germany, Italy, Netherlands, Spain, Sweden, the United Kingdom, Australia, Mexico, Republic of Korea, and Turkey. Updated on a monthly basis. Current data for crude oil and refined product stocks in Canada, Chile, Mexico, the United States (Western Hemisphere), France, Germany, Italy, Netherlands, Spain, the United Kingdom and Other Europe (Europe), Japan, Republic of Korea, Other Pacific (Asia-Pacific), and Total OECD (Table 12.1) Current data for refined product stocks in the OECD Western Hemisphere, OECD Europe, OECD Asia-Pacific and Total OECD. Products include gasoline, diesel and gasoil, and heavy fuel oil. Updated on a monthly basis (Table 12.2). 相似文献