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A sustainable materials management for metals should be achieved to conserve resources of metal minerals. For the sustainable materials management, material flows through the whole life cycle of materials have been recognized by material flow analysis (MFA) studies. Former MFA studies pointed out that cyclic use of metals could be enhanced not only by increasing quantity of recovered scrap but also by upgrading quality of the scrap. In general, the quality is degraded by contaminants which commingle at disassembling processes. The mixture of contaminants depends on usage of materials in products. Here, Type I ecolabelling has a potential to convey messages for avoiding mixture of contaminants to the producers of finished products. In this study, on the basis of a survey on existing certification criteria related to metals in the world, a general concept of certification criteria on sustainable materials management for metals in Type I ecolabelling system is proposed. Finally, we propose six criteria in the form of certification criteria in Type I ecolabelling system.  相似文献   
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预测结构性地表沉降引起的地下结构运动是一件非常重要的任务,特别是牵涉到年久的基础设施时(例如砌筑隧道和管道)。我们对这方面的了解还很有限,例如,隧疏王引爱土体运动时,砖衬隧道将如何变化?现在英国剑桥大学工程部的研究人员提出了一种解决方案。  相似文献   
3.
In this study, we present the development and application of a new ecosystem model coupled with a hydrodynamic model to describe the important physical, chemical and biological processes of an ecosystem in the marine environment, the Ariake Sea in the west coast of Kyushu, Japan. The model was calibrated and validated using in-situ field measurements from various monitoring stations in the sea. The presented results covered the period from January 1991 to December 2000. The results showed that chlorophyll-a, nutrients and dissolved oxygen levels varied seasonally in response to weather and boundary condition. Through this study, the model was shown to be able to handle the flooding and drying processes that usually exist and play an essential role over the estuarine-tidal flats of the sea.  相似文献   
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This article presents hydrodynamic forces and moments, surface pressures, estimated side force distributions, and wakes under oblique towing conditions for a practical tanker model (model KVLCC2M), which was designed by the Korea Research Institute of Ships and Ocean Engineering (KRISO). Ship offset data is readily available and can be obtained from the Internet. The model ship has no appendages and no rudder. Trim and sinkage were adjusted to zero in the static condition and the model ship was constrained against any motion. Although the drift angle β was primarily set to 0°, 6°, and 12°, other settings were used in some experiments. All experimental results were processed using uncertainty analysis. The uncertainty analyzing method follows the ANSI/ASME Performance Test Code (PTC19.1-1985) and the AIAA Standard S-071-1995. Only a few error components were considered here and they were empirically chosen because they had a heavy weighting when used in the uncertainty calculation. The results of these towing tank experiments will contribute to the development of computational fluid dynamics (CFD) research in ship hydrodynamics.  相似文献   
5.
The publicly-owned municipal bus sector that provides local transport in Japan is in a difficult situation because of operating deficits, inefficient operations and management, and budgetary constraints of expanding subsidies, and thus, it needs to be restructured to improve efficiency. This paper investigates the impact of subsidies and contractual settings on the cost structure of the publicly-owned bus sector in Japan. A trans-log cost function has been estimated by pooling cross-sectional data of 527 observations over the time period of 1990-2006 for a cross-section of 31 publicly-owned transport companies in Japan. Our analytical results confirm that governmental subsidies to this sector negatively affect the cost structure, while the contractual model may have a positive impact. We also discuss the implications of these results for Japan’s public transport policy.  相似文献   
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12世纪以后的濑户美浓窑是对福建陶瓷的模仿,是福建陶瓷的日本化生产.濑户美浓窑的模仿生产,时间上正值东亚社会的国际局势发生动乱的时期,技术工艺上受福建陶工的直接指导,濑户美浓窑所模仿生产的产品,均为日本饮食文化和茶文化中所需要的器皿.为福建陶瓷工来到濑沪美浓提供方便的是福建和濑户美浓的禅僧以及福建和堺市的海商,而12世纪末期构建起来的福建与堺市的贸易体系基础--东海太平洋禅宗网络的存在使陶工的移动成为可能.  相似文献   
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A serious interest in high speed train has been increasing all over the world. However, recent experiences in Asian countries show that high speed rail projects are not financially viable even in areas seemingly favorable to rail operations. Considering the existing intensive highway and airline network, putting public subsidies to high speed rail projects are barely justifiable from a purely economic point of view. What is required of any government which contemplates high speed rail construction as a policy option is to show taxpayers the cost/revenues difference between constructing a high speed rail line and expanding a capacity of other means, before proceeding.  相似文献   
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Thet(l4;18)chromosomaltranslocationsarerecognizedasacytogeneticabnormalityinB-celllymphomas,especiallyinfollicularlymphomas',>.Aputativeoncogeneonchromosome18bandq2ltermedB-cellleukemia-lymphoma-2(bcl-2)isjux-taposedtosegmentsoftheimmunog1obulin(Ig)heavy-chaingenelocatedonchromosome14bandq32.Bcl-2rearrangementsarecommonlyfoundinfollicularlymphomasintheAmericant2i.Howev-er,theconflictingresultsregardtoincidenceofthetranslocationinJapaneseB-ce1llymphomashasyieldedusingcytogeneticana1ysisandSo…  相似文献   
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Distribution of drifting seaweeds in eastern East China Sea   总被引:3,自引:0,他引:3  
In offshore waters with relatively low primary production, drifting seaweeds composed of Sargassum species form an identical ecosystem such as an oasis in desert. Commercially important pelagic fishes such as jack mackerel (Trachurus japonicus) and yellow tail (Seriola quinqueradiata) spawn in East China Sea pass their juvenile period accompanying drifting seaweeds. Therefore drifting seaweeds are very important not only in offshore ecosystem but also fishery resources. However the distribution of drifting seaweeds in East China Sea has scarcely known. Then we conducted two research cruises of R/V Hakuho–Maru in May 2002 and in March 2004. During the cruises, drifting seaweeds were visually observed from the bridge and sampled with a towing net. The observation revealed that the drifting seaweeds were distributed along the front between the Kuroshio Current and coastal waters and mainly composed of one seaweed species, Sargassum horneri (Turner) C. Agardh from spring to early summer. There are no reports on geographical distribution of this species in the coasts south of southern Kyushu Island in Japan. Kuroshio Current flows northeastward there. Buoys with GPS attached to drifting seaweeds released off Zhejiang Province, China, in March 2005 to track their transport. Their positions monitored by ORBCOM satellite showed that they were transported to the area in East China Sea, where the drifting seaweeds were observed during the cruises, in 2 months. These facts suggest that S. horneri detached from Chinese coast in March or months earlier than March could be transported to fringe area of continental shelf and waters influenced by Kuroshio Current from March to May. Therefore the Sargassum forests, especially S. horneri, along the Chinese coast play a very important role in the ecosystem of the East China Sea as a source of drifting seaweeds.  相似文献   
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