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1.
ABSTRACT

Land-Use Mix (LUM) refers to the strategy of integrating complementary functions within a building or area. While LUM has become a dominant approach in urban planning, its actual benefits and vision for spatial planning remain unclear. To clarify this issue, this study discerns the spatial features of land-use patterns depending on the compatibilities among land-use categories. Accordingly, this study introduces three LUM measures – adjacency, intensity, and proximity – to identify differences in the spatial distribution of land-use categories. Based on these measures, a land-use allocation model is developed to specify spatial patterns satisfying the given compatibilities. This model is tested by applying the concept of the neighborhood unit on a case study of normative land-use patterns subject to specified compatibilities. The results describe spatial features of four compatibility sets, including a set exhibiting a compatibility conflict between the same land-use pair and LUM measures when, for example, a given land-use pair is compatible in terms of intensity but incompatible in terms of proximity. Understanding the spatial features of a normative land-use pattern that satisfies various possible compatibilities will facilitate the incorporation of the LUM approach into local planning guidance and zoning ordinances.  相似文献   
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3.
The Global Warming Potential (GWP) index is currently used to create CO2-equivalent emission totals for multi-gas greenhouse targets. While many alternatives have been proposed, it is not possible to uniquely define a metric that captures the different impacts of emissions of substances with widely disparate atmospheric lifetimes, which leads to a wide range of possible index values. We examine the sensitivity of emissions and climate outcomes to the value of the index used to aggregate methane emissions using a technologically detailed integrated assessment model. The methane index is varied between 4 and 70, with a central value of 21, which is the 100-year GWP value currently used in policy contexts. We find that the sensitivity to index value is, at most, 10–18 % in terms of methane emissions but only 2–3 % in terms of the maximum total radiative forcing change, with larger regional emissions differences in some cases. The choice of index also affects estimates of the cost of meeting a given end of century forcing target, with total two-gas mitigation cost increasing by 7–9 % if the index is increased, and increasing in most scenarios from 4 to 23 % if the index is lowered, with a slight (1 %) decrease in total cost in one case. We find that much of the methane abatement occurs as the induced effect of CO2 abatement rather than explicit abatement, which is one reason why climate outcomes are relatively insensitive to the index value. We also find that the near-term climate benefit of increasing the methane index is small.  相似文献   
4.
A real-time forecast (RTF) system using Weather Research and Forecast (WRF) model version 2.2 is used to evaluate the diurnal variation of precipitation over South Korea in the summer (June to August) of 2007. The characteristics of the observed precipitation are also analyzed. The analysis and simulation period is divided into two sub-periods following the end of the changma, or East Asian monsoon, in 2007: Period_1 is from 1 June to 21 July, and Period_2 is from 22 July to 31 August. A 24-h precipitation cycle is observed over the entire period. The diurnal variation of precipitation over the South Korea shows that the nighttime maximum precipitation in Period_1 is affected by a largescale system; in contrast, the daytime maximum precipitation in Period_2 resulted from mesoscale convections is induced by thermal instability and moisture advection. The phases of the diurnal variation of simulated precipitation are consistent with those of the observed precipitation. The daytime rainfall amount of simulated precipitation in Period_2 is overestimated, and the convective rain process significantly affects the simulated total precipitation. The daytime overestimated precipitation is associated with overestimations of low-level temperature and moisture during the daytime in the model simulations as compared with the observations.  相似文献   
5.
The Al–Mg-rich granulites from the In Ouzzal craton, Algeria, show a great diversity of mineral reactions which correspond to continuous equilibria as predicted by phase relationships in the FeO–MgO–Al2O3–SiO2 system. The sequence of mineral reactions can be subdivided into three distinct stages: (1) a high-P stage characterized by the growth of coarse mineral assemblages involving sapphirine and the disappearance of early corundum and spinel-bearing assemblages; (2) a high-T stage characterized by the development of Sa–Qz-bearing assemblages; and (3) a later stage, in which garnet-bearing assemblages are replaced by more or less fine symplectites involving cordierite. During the course of early mineral reactions, the distribution coefficient, Kd, between the various ferromagnesian phases decreased significantly whereas Al2O3 in pyroxene increased concomitantly. These observations, when combined with topological constraints, clearly indicate that the high-P stage 1 was accompanied by a significant rise in temperature (estimated at 150 ± 50° C) under near isobaric conditions, in agreement with the reaction textures. By stage 2, pressure and temperature were extreme as evidenced by the low Kd value between orthopyroxene and garnet (Kd= 2.06–1.99), the high alumina content in pyroxene (up to 11.8%) and the high magnesium content in garnet [100 Mg/(Mg + Fe) = 60.6]. Mineral thermometry based on Fe–Mg exchange between garnet and pyroxene and on Al-solubility in pyroxene gives temperatures close to 970 ± 70° C at 10 ± 1.5 kbar. These results are in agreement with the development of Sa–Qz assemblages on a local scale. Late mineral reactions have been produced during a decompression stage from about 9 to 6 kbar. Except for local re-equilibration of Mg and Fe at grain boundaries, there is no evidence for further reactions below 700° C. We interpreted the whole set of mineral reactions as due to changes in pressure and temperature during a tectonic episode located at c. 2 Ga. Because of the lack of evidence for further uplift after the thermal relaxation which occurred at c. 6 kbar, it is possible however that the exhumation of this granulitic terrane occurred in a later tectonic event unrelated to its formation.  相似文献   
6.
The results of UV-observations at 1640 Å of the regions of stellar associations Per OB1, Sco OB1, and Cyg OB1 made with the space telescope Glazar are presented. Respectively, 42, 22, and 30 hot stars brighter than 10m at 1640 Å were detected and measured in the mentioned stellar associations. A few of them are suspected to be variable in far UV.  相似文献   
7.
High-resolution summer rainfall prediction in the JHWC real-time WRF system   总被引:3,自引:0,他引:3  
The WRF-based real-time forecast system (http://jhwc.snu.ac.kr/weather) of the Joint Center for High-impact Weather and Climate Research (JHWC) has been in operation since November 2006; this system has three nested model domains using GFS (Global Forecast System) data for its initial and boundary conditions. In this study, we evaluate the improvement in daily and hourly weather prediction, particularly the prediction of summer rainfall over the Korean Peninsula, in the JHWC WRF (Weather Research and Forecasting) model system by 3DVAR (three-Dimensional Variational) data assimilation using the data obtained from KEOP (Korea Enhanced Observation Program). KEOP was conducted during the period June 15 to July 15, 2007, and the data obtained included GTS (Global Telecommunication System) upper-air sounding, AWS (Automatic Weather System), wind profiler, and radar observation data. Rainfall prediction and its characteristics should be verified by using the precipitation observation and the difference field of each experiment. High-resolution (3 km in domain 3) summer rainfall prediction over the Korean peninsula is substantially influenced by improved synoptic-scale prediction in domains 1 (27 km) and 2 (9 km), in particular by data assimilation using the sounding and wind profiler data. The rainfall prediction in domain 3 was further improved by radar and AWS data assimilation in domain 3. The equitable threat score and bias score of the rainfall predicted in domain 3 indicated improvement for the threshold values of 0.1, 1, and 2.5 mm with data assimilation. For cases of occurrence of heavy rainfall (7 days), the equitable threat score and bias score improved considerably at all threshold values as compared to the entire period of KEOP. Radar and AWS data assimilation improved the temporal and spatial distributions of diurnal rainfall over southern Korea, and AWS data assimilation increased the predicted rainfall amount by approximately 0.3 mm 3hr?1.  相似文献   
8.
长期以来苏北地工陆相中生界地层问题突出,表现在对钻井地层划分对比上观点很不统一,对地层发育与分布的认识模糊不清。通过地层古生物、钻井地层划分对比研究,结合多方面最新资料和成果,对象山群的分布范围、葛村组的发育与分布、“黑浦口”的归属等问题,提出了新观点。  相似文献   
9.
顾志方  赵水霖 《江苏地质》2000,24(3):148-152
介绍了如何将互联网技术应用于石油行业的局域网或广域网中,在服务器端提供图形信息数据库的服务,并在客户端利用浏览器进行图形信息的查询,实现勘探开发图形信息的共享。  相似文献   
10.
着重介绍了镇江市矿山企业的经营现状,并对其矿业结构和所有制结构下的主要经济指标作了初步剖析,从而对全市的矿业特征有了更深层次的了解。  相似文献   
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