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101.
The experimental results from infrared thermography surveys over two buildings externally exposed walls are presented. Data acquisition was performed on a static configuration by recording direct and indirect solar loading during several days and was processed using advanced signal processing techniques in order to increase signal-to-noise ratio and signature contrast of the elements of interest. It is demonstrated that it is possible to detect the thermal signature of large internal structures as well as surface features under such thermographic scenarios. Results from a long-wave microbolometer compared favorably to those from a mid-wave cooled infrared camera for the detection of large subsurface features from unprocessed images. In both cases, however, advanced signal processing greatly improved contrast of the internal features.  相似文献   
102.
The minimal dominating set for a digraph (directed graph) is a prototypical hard combinatorial optimization problem. In a previous paper, we studied this problem using the cavity method. Although we found a solution for a given graph that gives very good estimate of the minimal dominating size, we further developed the one step replica symmetry breaking theory to determine the ground state energy of the undirected minimal dominating set problem. The solution space for the undirected minimal dominating set problem exhibits both condensation transition and cluster transition on regular random graphs. We also developed the zero temperature survey propagation algorithm on undirected Erdös-Rényi graphs to find the ground state energy. In this paper we continue to develope the one step replica symmetry breaking theory to find the ground state energy for the directed minimal dominating set problem. We find the following. (i) The warning propagation equation can not converge when the connectivity is greater than the core percolation threshold value of 3.704. Positive edges have two types warning, but the negative edges have one. (ii) We determine the ground state energy and the transition point of the Erdös-Rényi random graph. (iii) The survey propagation decimation algorithm has good results comparable with the belief propagation decimation algorithm.  相似文献   
103.
Public perceptions about nanotechnology: Risks,benefits and trust   总被引:8,自引:7,他引:1  
We report data from the first representative national phone survey of Americans' perceptions about nanotechnology (N =1536). Public opinion about nanotechnology is in its infancy, and knowledge about it is quite limited. Yet, Americans' initial reaction to nanotechnology is thus far generally positive, probably rooted in a generally positive view of science overall. Survey respondents expected benefits of nanotechnology to be more prevalent than risks, and they reported feeling hopeful about nanotechnology rather than worried. Their most preferred potential benefit of nanotechnology is new and better ways to detect and treat human diseases, and they identified losing personal privacy to tiny new surveillance devices as the most important potential risk to avoid. The most discouraging aspect to the data is respondents' lack of trust in business leaders to minimize nanotechnology risks to human health. Overall, these data indicate that while Americans do not necessarily presume benefits and the absence of risks, their outlook is much more positive than not.  相似文献   
104.
车载激光采集系统中三维信息联合解算方法   总被引:1,自引:0,他引:1  
深入讨论了车载激光三维数据采集系统中解算三维信息的关键技术,给出了一套完整的GPS、IMU和激光扫描数据交叉整合的工程方法,实时、主动、快速获取导目标表面的三维信息。该方法已经在实际应用中得到验证。  相似文献   
105.
Nanotechnology is projected to be a very promising field, and the impact of nanotechnology on society is increasingly significant as the research funding and manufactured goods increase exponentially. A clearer picture of Taiwan’s current and future nanotechnology industry is an essential component for future planning. Therefore, this investigation studies the progress of industrializing nanotechnology in Taiwan by surveying 150 companies. Along with understanding Taiwan’s current nanotechnology industrialization, this paper also suggests ways to promote Taiwan’s nanotechnology. The survey results are summarized and serve as the basis for planning a nanotechnology industrialization strategy.  相似文献   
106.
A statistical procedure is applied to surveys which elicit discrete ordinal data so that groupings of questions analogous to factors may be identified. The statistical procedure, termed prediction analysis, develops a measure which reflects the conformability of a set of data to an articulated expectation. A case is presented.  相似文献   
107.
采用自编的大学物理课程思政问卷,以笔者所带的湖北文理学院正在学习大学物理课程的学生为样本,实施问卷调查.问卷显示,70%左右的学生需要大学物理课程思政,80%左右的学生接受大学物理课程思政线上教学.分析了学生做出这些选择的原因,同时调研了他们对大学物理课程思政有哪些期许.对如何改进大学物理课程思政具有一定的指导意义.  相似文献   
108.
Statistical methods to produce inferences based on samples from finite populations have been available for at least 70 years. Topics such as Survey Sampling and Sampling Theory have become part of the mainstream of the statistical methodology. A wide variety of sampling schemes as well as estimators are now part of the statistical folklore. On the other hand, while the Bayesian approach is now a well-established paradigm with implications in almost every field of the statistical arena, there does not seem to exist a conventional procedure—able to deal with both continuous and discrete variables—that can be used as a kind of default for Bayesian survey sampling, even in the simple random sampling case. In this paper, the Bayesian analysis of samples from finite populations is discussed, its relationship with the notion of superpopulation is reviewed, and a nonparametric approach is proposed. Our proposal can produce inferences for population quantiles and similar quantities of interest in the same way as for population means and totals. Moreover, it can provide results relatively quickly, which may prove crucial in certain contexts such as the analysis of quick counts in electoral settings.  相似文献   
109.
The focus of the National Cooperative Soil Survey is shifting from producing static, printed soil survey reports to providing a dynamic resource of soils information for a wide range of needs. The National Soil Information System (NASIS) is the core component of this vision and is designed to manage and maintain soil data from collection to dissemination. NASIS supports this conceptual shift in three important areas: (1) collection of new information in compliance with standards, (2) application of expert knowledge to make information usable for a variety of purposes, and (3) dissemination of information to a wide variety of users. This paper demonstrates the use of NASIS for evaluating the suitability of military lands for vehicle related land-use activities.  相似文献   
110.
Microplastics have sparked global concern due to their negative effects on organisms' health and the environment. Microplastics research in protected areas (marine and freshwater) has recently gained prominence and is expected to grow in the coming years. This review of 36 published studies examines current progress and identifies future research challenges. It begins with an overview of microplastic evaluation methodologies, followed by a discussion of recent advances in the abundance of microplastics in water, sediment, biota, wet and dry deposition, and particulate matter. Current quality assurance and control measures are also summarized. The majority of studies (44 %) examined sediment samples. In biota, the gastrointestinal system was the most evaluated for microplastics. Digestion (using H2O2 and KOH) and density separation (using NaCl) are the most common microplastic extraction methods. We found that microplastic contamination is pervasive in all the surveyed protected areas, with varying levels of abundance geographically, and over 50 % of the biota ingest microplastics. The methodological discrepancies amongst the investigations, from sampling to microplastics characterization, make it difficult to compare the results and generate baseline data on microplastic contamination levels. Close monitoring and a standardized approach are thus required to determine the extent to which microplastics might enter and persist in protected area environments, as well as to devise effective mitigating strategies.  相似文献   
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