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1.
The Distribution of Amphipoda in a Brackish-Water Lagoon in Greece   总被引:1,自引:0,他引:1  
Abstract. The distribution of the benthic Amphipoda was studied in the brackish-water lagoon Mazoma of Amvrakikos Bay, Ionian Sea, Greece. Eleven amphipod species typical of the sublittoral zone, some with preference for enclosed bays and lagoons, were identified. Gammarus crinicornis, Microdeutopus bifidus, C. rotundirostris , and Erichthonius difformis are mentioned for the first time for Greek waters. The distribution of amphipods in the lagoon is governed by the vegetation and is probably modified by interspecific relations.  相似文献   
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Since the introduction of Xerox PARC Map Viewer, there is a high growth in the number of Web GIS (Geographical Information System) applications for public use in different contexts. These applications instruct, advise and provide the tools for spatial analysis to their users, and the people who use them depend or rely on these systems. Many of these users are non-experts who have no GIS expertise and a limited understanding of spatial data handling. These inherent characteristics of non-expert interaction establish risk and uncertainty, which are further increased due to the complexity of Web GIS interfaces. These issues of uncertainty, risk perception and dependence are all trust-related aspects. Online trust has been repeatedly identified as a major concept for online information systems and its value recognised as it influences the intentions to use and the acceptance of online systems and the overall user experience. However, there is a very limited understanding as to exactly how trust is constructed when people, especially non-experts, interact with Web GIS. To improve knowledge in this domain, this article explores the theoretical foundations on how trust can be investigated in this context. Trust studies (mainly from the e-commerce domain) suggest that a trust-oriented interface design may improve the trustworthiness of online systems, and such attention can be given to Web GIS interfaces. Such studies are reviewed and their applicability is considered in the Web GIS context, taking into consideration their special characteristics. A case study is used to discuss how some features may potentially influence the trustworthiness of Web GIS applications. This article concludes by suggesting future research directions for the implementation of a holistic approach, which is necessary to investigate trust in this context.  相似文献   
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Fan  Jihui  Motamedi  Artemis  Galoie  Majid 《Natural Hazards》2021,106(1):595-612

In this study, the effect of downstream lakes or ponds on dam break flow was investigated. To do this, a robust finite volume method with Harten-Lax-van Leer contact surface Riemann’s solver technique for flux evaluation has been used. For space discretization, a triangular mesh grid was used and a complete software with mesh generator was developed. A reservoir with a long downstream channel was assumed, and many scenarios such as a single lake with various lengths, widths and positions along the channel and multiple consecutive lakes as symmetric and non-symmetric with respect to the channel centerline were considered. The numerical modeling of dam break flow along the channel showed that the downstream lake can decrease the speed and depth of the dam break wave front and the amount of this wave attenuation was very dependent on the storage volume of the lake and vortexes which were established in the lake.

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The northernmost Kamchatka Peninsula is located along the northwestern margin of the Bering Sea and consists of complexly deformed accreted terranes. Progressing inland from the northwestern Bering Sea, the Olyutorskiy, Ukelayat and Koryak superterranes (OLY, UKL and KOR) are crossed. These terranes were accreted to the backstop Okhotsk-Chukotsk volcanic-plutonic belt (OChVB) in northernmost Kamchatka. A sedimentary sequence of Albian to Maastrichtian age overlaps the terranes and units of the Koryak superterrane, and constrains their accretion time. A paleomagnetic study of blocks within the Kuyul (KUY) terrane of the Koryak superterrane was completed at two localities (Camp 2: λ=61.83°N, φ=165.83°E and Camp 3: λ=61.67°N, φ=164.75°E). At both localities, paleomagnetic samples were collected from Late Triassic (225–208 Ma) limestone blocks (2–10 m in outcrop height) within a melange zone. Although weak in remanent magnetization, two components of remanent magnetization were observed during stepwise thermal demagnetization at 32 sites. The A component of magnetization was observed between room temperature and approximately 250 °C. This magnetic component is always of downward directed inclination and shows the best grouping at relatively low degrees of unfolding. Using McFadden–Reid inclination-only statistics and averaging all site means, the resulting A component mean is Iopt=60.3°, I95=5.0° and n=36 (sites). The B magnetic component is observed up to 565 °C, at which temperature, most samples have no measurable remanent magnetization, or growth of magnetic minerals has disrupted the thermal demagnetization process. Combining sites with Fisher estimates of kappa (k-value)≥13 and n (sites)≥3, where bedding orientation differs within a block, most of these sites show the best grouping of B component directions at 100% unfolding, and two of the blocks display remanent magnetizations of both upward and downward directed magnetic inclination. Combining sites with Fisher estimates of kappa (k-value)≥13 and n (sites)≥3, the resulting overall B component paleolatitude and associated uncertainty are λobs=30.4°N or S, λ95=8.9° and n=19 (sites). When compared with the expected North America paleolatitude of λAPWP expected=57.9°N, our data support a model in which blocks within the Koryak superterrane are allochthonous and far travelled.  相似文献   
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Attesting to the powerful capabilities and in technology trends, many scholars envisioned the consolidation of geographic information systems (GIS) into vital tools for disseminating spatial information. GIS are presently used to inform, advise and instruct users in several contexts and to further engage citizens in decision-making processes that can impact and sustain policy development. Interaction with these applications incorporates risk and uncertainty, which have been repeatedly identified as preconditions in nurturing trust perceptions and which instigate a user's decision to rely on a system and act on the provided information. Research studies consistently demonstrated that a trust-oriented interface design can facilitate the development of more trustworthy, mainly e-commerce, systems. Trust in the Web GIS context, despite its significance, has only relatively recently received some attention. A set of human–computer interaction (HCI) user-based studies revealed some Web GIS trustee attributes that influence non-experts' trust beliefs and found that when these are problematic or absent from interface design, users form irrational trust perceptions, which amplifies the risk and may impose dangers to the user. These Web GIS trustee attributes that influence non-experts' trust perceptions are formulated here into a set of trust guidelines. These are then evaluated using the PE-Nuclear tool, a Web GIS application, to inform the public about the site selection of a nuclear waste repository in the United Kingdom. Our preliminary results indicate that the proposed trust guidelines not only support the development of rational trust perceptions that protect non-experts from inappropriate use of Web GIS technology but also contribute towards improving interaction with such applications of public interest issue.  相似文献   
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Abstract. The polychaetc fauna was studied in 18 soft-bottom stations in Amvrakikos Bay of the Ionian Sea. Of the 146 species found many had single occurrences, which caused low similarity between stations. Mixing and renewal of water influenced the distribution of species and feeding types of polychaetes, while their diversity correlated with sedimentary structure. Water depth was the factor which accounted for the greatest variability in the data, whereas salinity had no discernible effect on the polychaetc fauna.  相似文献   
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Allemagne     
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