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ITQs have not yet been introduced by the Government of Japan. In coastal areas, fishery cooperative associations have traditionally played an important role in managing fisheries through self-imposed rules and peer-monitoring systems. Recently, however, the economic competitiveness of Japanese fisheries in the international market is being questioned. In this paper, a detailed examination of the pros and cons of the current system in Japan is compared to the current fishery management measures of Iceland and the United States, where attaining economically or biologically efficient outcomes may be prioritized in making fisheries management decisions. For many coastal fisheries in Japan, maintaining a management scheme in which stakeholders play an active role in determining fisheries measures seems more relevant if their priority is to maintain the stability of coastal communities and equity of stakeholders. Intensive dialog among stakeholders would be necessary to identify shared objectives of their fishery operations and to make decisions to establish specific steps toward the goal of increasing economic efficiency, environmental sustainability, or stability of communities and equity of stakeholders.  相似文献   
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The results of geological, geochemical and isotopic investigations in the Hengill thermal area in Iceland are presented. This area may be regarded as typical of the Icelandic high temperature areas. The Hengill area is mainly built up of pillow lavas and hyaloclastites, which were piled up in subglacial eruptions. Its western half is traversed by a very active NE-SW trending fault zone about 5 km broad, within which are several eruptive fissures of postglacial age. The volcanic rocks are basalts of various kinds, but minor occurrences of intermediate and rhyolitic rocks are also found. Solfataras and fumaroles occur mainly at higher altitude. Within the fault zone they have a linear distribution along faults. Hot water springs are found in the lowlands on the southern border of the thermal area. The concentrations of chlorine, tritium and deuterium in the water indicate that the hot springs on the lowland are fed by a deep lying aquifer which receives water from a recharge area situated in the western branch of the active volcanic zone upto 70 km to the northeast. The hot springs at higher altitude are the outlets of a secondary circulation system fed by local rain water. This water derives its heat partly from the heat content of the rocks penetrated and partly by steam and gas boiled off from the deeper lying aquifer. Preliminary results from other high temperature areas in Iceland indicate the presence of similar hydrological systems.  相似文献   
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Very high resolution hyperspectral data should be very useful to provide detailed maps of urban land cover. In order to provide such maps, both accurate and precise classification tools need, however, to be developed. In this letter, new methods for classification of hyperspectral remote sensing data are investigated, with the primary focus on multiple classifications and spatial analysis to improve mapping accuracy in urban areas. In particular, we compare spatial reclassification and mathematical morphology approaches. We show results for classification of DAIS data over the town of Pavia, in northern Italy. Classification maps of two test areas are given, and the overall and individual class accuracies are analyzed with respect to the parameters of the proposed classification procedures.  相似文献   
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Successful in situ groundwater remediation relies on the adequate distribution of treatment materials within the subsurface. Zero‐valent iron (ZVI) is widely used for the remediation of soils contaminated with chlorinated organic compounds. Because ZVI is a solid, various techniques are used to distribute ZVI in the subsurface; however, a major uncertainty in this process involves determining the distribution of the iron during emplacement. A method of mapping the distribution of ferromagnetic material such as ZVI is by magnetic susceptibility (MS), a novel approach that is highly sensitive, quantitative, objective, and easily applied in field. The method has been tested in the laboratory on synthetic cores containing EHC®, an organic amendment containing 40 to 50% ZVI, using an MS meter with two types of sensors (loop and handheld). Both sensors have high sensitivity (e.g., 1% disseminated EHC is easily detected), whereas the hand‐held sensor has greater spatial resolution (e.g., differences are notable on a scale of 1 cm). Following the laboratory studies, the handheld instrument was used to perform field measurements for multiple pilot studies and a full‐scale application of EHC using various delivery methods (pneumatic fracturing, hydraulic fracturing, and direct injection) to construct a biobarrier at a field remedial site. The MS method has proven invaluable in quantifying amendment distribution and ensuring appropriate application of this remedial technology.  相似文献   
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