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101.
海峡西岸城市群是中国经济快速发展的热点地区,研究其城市活力与城市扩张的耦合关系对促进城市建设意义重大。本研究以 DMSP-OLS 和 NPPVIIRS夜间灯光数据为数据源提取1992—2017年该城市群城市建成区,利用城市扩张率指数等对城市扩张的动态及其演变特征进行分析;应用熵值法、耦合协调度模型等评估城市活力,在此基础上,探究了对应城市活力和城市扩张耦合关系。结果表明:在研究期间,海峡西岸城市群城市建成区面积增加了23228.79km2;城市活力呈逐步逐年增加趋势;城市活力与城市扩张的耦合协调性逐步增强;经济发展和城市规划、地理区位优势等因素也对研究区城市活力与城市扩张及其耦合协调度的变化有影响。本研究可为城市群时空演变及其城市活力评价分析提供方法借鉴与数据支持。 相似文献
102.
This paper explains how a permissive planning permit system is embedded in Belgian/Flemish society and how this contributes to urban sprawl. We base our analysis on an institutionalist approach as developed in previous and current research and analyse the Flemish planning permit system since 1962 as one of different interacting planning systems, all (re)produced, maintained, transformed and struggled over by specific individual and collective actors and shaped by a range of institutional dynamics. The analysis shows how in the dynamics of the Flemish planning permit system, a general struggle between actors defending property-based private initiative and actors arguing for collective action in space is especially apparent. In this struggle, property ownership expressed through a permissive planning permit system and limited enforcement of regulations is seen to be predominant, especially in the 1960s, 1980s and 2000s. Changes in the 1990s, making the planning permit system more strict, have partly and momentarily challenged the institutional frame which structures the predominant planning permit practice, but left the logic of individual property largely untouched. Today, the Flemish planning permit system has again been reoriented towards the protection of private property, which hampers the capacity of government to implement a coherent spatial policy. 相似文献
103.
W. PENN HANDWERKER 《Reviews in Anthropology》2013,42(1):105-118
This article evaluates six recent contributions to the literature on ethnographic research methods. Four concern collecting and analyzing texts, one introduces the use of textual and numerical data, and one illustrates the use of quantitative methods for qualitative data. The first four books reveal that current thinking in qualitative methods continues to privilege inexplicit criteria for data collection and analysis despite recognizing that explicit criteria work best. The last two books show how to effectively integrate qualitative and quantitative data in ways that resolve these contradictions. 相似文献
104.
Richard Jensen 《Historical methods》2013,46(4):174-176
Searching, gathering, organizing, and retrieving data are basic tasks for historians. As long as historians work by themselves, decisions concerning data format, data exchange, computer platform, and the like remain secondary. Teams of historians often use relational databases for centralized data storage. However, fundamental risks are implicit when one uses databases. Among technical considerations, the process of transformation between the source and the database is a deciding factor. For those who gather data, the effective use of such possibilities as data exchange, compatibility, and simplicity of survey and the reuse of the data in other contexts and platforms becomes increasingly important. In contrast, the user's needs include the possibility of data verification and use of the data for more than one question. Many relational databases have considerable shortcomings because the stored data lose the visual characteristics, the syntax, and the semantics of the original source. The EuroClimHist database environment is a part of the NCCR Climate project. It uses a data tool, written in Java for the gathering of documentary data, which generates extensible markup language (XML) files for data exchange. 相似文献
105.
Abstract In this article, the author presents a strategy for designing relational databases with the program FileMaker Pro (FileMaker) to study the histories of individuals and organizations. The approach facilitates efficiency in inputting data and flexibility for constructing statistical analyses from the raw data. The key feature of the strategy is to define the basic unit of observation in the database in terms of an agent, an event, and a date. Given that programs such as FileMaker can easily sort data by agent and date, once one structures the data correctly, he or she can construct well-ordered event histories for agents, even if the researcher enters the data in an unordered fashion. By using events that happened to an agent at a particular time as the basic unit of observation, one maintains maximum flexibility to do statistical analysis that aggregates basic data in different ways. This article illustrates the power of the approach by outlining ways to analyze changes in geographic distances between two events marking the life histories of chemists. 相似文献
106.
Daniel Scott Smith 《Historical methods》2013,46(3):141-148
AbstractHistorians seeking to identify the Irish have overwhelmingly relied upon nominal record linkage, thus limiting studies to periods and contexts in which corroborating records exist. Surname analysis provides an alternative: a subset of 283 Irish surnames was able to correctly isolate 40 percent of known Irish individuals across thousands of entries, which is sufficient for sampling the Irish in demographic studies. This conclusion was based on an analysis of 278,949 names from the London area in the 1841 census, and was tested and refined against 42,248 historical records pertaining to the poor in London between 1777 and 1820. 相似文献
107.
Generation of fluids during metamorphism can significantly influence the fluid overpressure, and thus the fluid flow in metamorphic terrains. There is currently a large focus on developing numerical reactive transport models, and with it follows the need for analytical solutions to ensure correct numerical implementation. In this study, we derive both analytical and numerical solutions to reaction‐induced fluid overpressure, coupled to temperature and fluid flow out of the reacting front. All equations are derived from basic principles of conservation of mass, energy and momentum. We focus on contact metamorphism, where devolatilization reactions are particularly important owing to high thermal fluxes allowing large volumes of fluids to be rapidly generated. The analytical solutions reveal three key factors involved in the pressure build‐up: (i) The efficiency of the devolatilizing reaction front (pressure build‐up) relative to fluid flow (pressure relaxation), (ii) the reaction temperature relative to the available heat in the system and (iii) the feedback of overpressure on the reaction temperature as a function of the Clapeyron slope. Finally, we apply the model to two geological case scenarios. In the first case, we investigate the influence of fluid overpressure on the movement of the reaction front and show that it can slow down significantly and may even be terminated owing to increased effective reaction temperature. In the second case, the model is applied to constrain the conditions for fracturing and inferred breccia pipe formation in organic‐rich shales owing to methane generation in the contact aureole. 相似文献
108.
109.
《Journal of Geography in Higher Education》2012,36(3):350-366
This study developed an interview-based critical spatial thinking oral test and used the test to investigate the effects of Geographic Information System (GIS) learning on three components of critical spatial thinking: evaluating data reliability, exercising spatial reasoning, and assessing problem-solving validity. Thirty-two students at a large state university completed pre- and post-tests administered during the 2010 fall semester. This study found positive relationships between GIS learning and critical spatial thinking. We argue that the improvement can be attributed to students' experiences in a GIS course. 相似文献
110.
Fragility functions that estimate the probability of exceeding different levels of damage in slab-column connections of existing non-ductile reinforced concrete buildings subjected to earthquakes are presented. The proposed fragility functions are based on experimental data from 16 investigations conducted in the last 36 years that include a total of 82 specimens. Fragility functions corresponding to four damage states are presented as functions of the level of peak interstory drift imposed on the connection. For damage states involving punching shear failure and loss of vertical carrying capacity, the fragility functions are also a function of the vertical shear in the connection produced by gravity loads normalised by the nominal vertical shear strength in the absence of unbalanced moments. Two sources of uncertainty in the estimation of damage as a function of lateral deformation are studied and discussed. The first is the specimen-to-specimen variability of the drifts associated with a damage state, and the second the epistemic uncertainty arising from using small samples of experimental data and from interpreting the experimental results. For a given peak interstorey drift ratio, the proposed fragility curves permit the estimation of the probability of experiencing different levels of damage in slab-column connections. 相似文献