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1.
Abstract

In recent years, to prevent accidents and disaster are desired by implementing maintenance and management of facilities, such as conducting periodic inspections with appropriate frequency at plants. However, because the dangerous materials such as flammable gas and explosives is used in a plant, and there are many dangerous places in a plant such as high-temperature environment and high places and narrow spaces, it is desirable to use a remote-controlled robot for safety work and short inspections. Against this background, the Disaster Robotics Category-Plant Disaster Prevention Challenge was held in Japan at the World Robot Summit 2018. Our team was ranked 3rd in this competition, because our strategy of ‘inspection and investigation in cooperation with UGV and UAV’ was effective. In this paper, the competition contents of World Robot Summit 2018 and the robot inspection system that we are studying are explained. And what kind of strategy was challenged and result for these given competition tasks by using our robot system are introduced. And the lessons learned such as advantages and issues in UGV and UAV collaboration work at this competition are described for evaluate a robot investigation system for disaster response and inspection work at plants.  相似文献   
2.
This paper characterizes stress levels via a self‐similarity analysis of the electrodermal activity (EDA) collected in a real‐world driving context. To characterize the EDA richness over scales, the fractional Brownian motion (FBM) process and its corresponding exponent H, estimated via a wavelet‐based approach, are used. Specifically, an automatic scale range selection is proposed in order to detect the linearity in a log scale diagram. The procedure is applied to the EDA signals, from the open database drivedb, originally captured on the foot and the hand of the drivers during a real‐world driving experiment, designed to evoke different levels of arousal and stress. The estimated Hurst exponent H offers a distinction in stress levels when driving in highway versus city, with a reference to restful state of minimal stress level. Specifically, the estimated H values tend to decrease when the driving environmental complexity increases. In addition, the estimated H values on the foot EDA signals allow a better characterization of the driving task than that of hand EDA. The self‐similarity analysis was applied to various physiological signals in literature but not to the EDA so far, a signal which was found to correlate most with human affect. The proposed analysis could be useful in real‐time monitoring of stress levels in urban driving spaces, among other applications.  相似文献   
3.
A major challenge in understanding how biological cells arose on the early Earth is explaining how RNA and membranes originally colocalized. We propose that the building blocks of RNA (nucleobases and ribose) bound to self-assembled prebiotic membranes. We have previously demonstrated that the bases bind to membranes composed of a prebiotic fatty acid, but evidence for the binding of sugars has remained a technical challenge. Here, we used pulsed-field gradient NMR spectroscopy to demonstrate that ribose and other sugars bind to membranes of decanoic acid. Moreover, the binding of some bases is strongly enhanced when they are linked to ribose to form a nucleoside or – with the addition of phosphate – a nucleotide. This enhanced binding could have played a role in the molecular evolution leading to the production of RNA.  相似文献   
4.
ABSTRACT

Social licence to operate (SLO) is a term that is finding increasing acceptance in a number of industries. Like all new terms, its precise meaning and implications are still being investigated. Using data from previous studies, this paper offers an analysis of the SLO of two case studies with each study being viewed separately through the grid of a distinct theoretical framework. Case study 1 looks at the development of differential social licence negotiated in the Hamlet of Cambridge Bay, Nunavut, as a result of an impact and benefit agreement negotiated between Tahera Diamond Corp. and the Kitikmeot Inuit Organisation in 2004. The study demonstrates that general acceptance of resource development can be uneven and reflect an unequal distribution of decision-making power. In case study 2, stakeholders of a failed mineral development project were queried across time about the specifics of the proposed mine development and were queried about resource development across different levels of consciousness. Perhaps, SLO is variable across different levels of consciousness. The paper concludes with observations about the variable nature of SLO acceptance across populations and across levels of consciousness within individuals. Perhaps, the concept of SLO is, in fact, complex, difficult to define and measure and, at this point, of limited utility as a measure of resource development acceptance.  相似文献   
5.
With more than one billion people lacking access to electricity in the world, ensuring universal access to electricity by 2030 remains a major challenge which cannot be left to the government initiatives alone. Access to local information and identification of potential areas for investment can be a challenge for investors. This paper provides a tool for preliminary assessment of potential markets for off-grid electrification in developing countries and applies this to Ghana to demonstrate its applicability. A multi-criteria approach is used to rank the districts according to the overall potential and the best markets and least favourable areas for investment are identified. The tool offers flexibility to include new inputs to the analysis and the factor weights can be adjusted as appropriate. The case study shows that the tool can effectively identify potential areas from a list of candidates and offers support to analysts.  相似文献   
6.
The lack of consensus on the meaning of energy security and how it should be measured hinders the evaluation of alternatives for improving the Cape Verdean energy sector. The objective of the paper is to develop an energy security index adjusted to the country's context. The methods used are the multi-criteria analysis and the Delphi survey. Different alternatives to improve energy security are assessed: electrically interconnect Cape Verde's islands, increase the share of renewable energy, and a combination of the previous alternatives. The results of our analysis indicate that increasing renewable energy is the optimal alternative for Cape Verde.  相似文献   
7.
对聚氨酯塑胶跑道行业发展现状及问题进行概述,解读了新国标GB 36246-2018《中小学合成材料面层运动场地》对运动场地材料物理机械性能和化学指标的新限量。为适应新国标要求,聚氨酯塑胶跑道从环保配方体系设计和施工质量方面均做出了改进,最后简要介绍聚氨酯塑胶跑道未来发展趋势。  相似文献   
8.
2020年,预计全球贸易进展局势出现缓和,世界经济增长小幅回升至2.6%左右,主要经济体面临的贸易政策、货币政策和地缘政治局势等不确定性因素仍较多,世界经济增长面临的下行风险仍较大。2019年中国经济总体平稳,GDP增长6.1%。2020年我国经济将继续保持增长稳健、结构优化、动能转换的发展态势,预计将实现6.0%的增长。  相似文献   
9.
于大河 《煤炭技术》2004,23(6):71-72
叙述了在施工软岩巷道交岔点中采用的一种新的支护方式 ,即锚索—锚杆—网喷碹 ,为软岩大断面快速施工创出了一条新的途径  相似文献   
10.
中国煤炭资源型城市化剖析   总被引:2,自引:0,他引:2  
李新春  李贤功  赵晶 《中国矿业》2006,15(11):20-23
煤炭资源型城市在我国工业经济中起着举足轻重的作用。本论文从城市的形成和发展阐述了煤炭资源型城市形成原因和内涵;剖析了我国煤炭资源型城市基本特征和城市化过程中存在问题;提出了中国煤炭资源型城市研究思路和研究内容,是接续研究的基础。  相似文献   
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