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11.
证据理论及其在评估中的应用   总被引:1,自引:0,他引:1  
针对新开设课程的课时设置问题,鉴于专家评估法存在的不确定性现象,采用D-S证据理论融合不确定性信息的方法,将每位专家的意见综合为专家组的一致意见,使评估结果更为合理,并为其它课程的课时设置提供借鉴.  相似文献   
12.
从理性泡沫的一般理论模型出发,主要采用久期依赖法(duration dependence)对上证综合指数进行了理性泡沫的实证检验,并用观察性证据(anecdotal evidence)进行了验证。研究发现,中国股市的各种特征很符合理性泡沫模型的推论,支持了中国股市理性泡沫的存在性。而中国股市理性泡沫的成因有其制度上的特殊性,这是由我国股市的特殊发展轨迹所决定的。  相似文献   
13.
Wheat is one of the most important crops in both China and the world, and its domestication can be traced back to ~10000 years ago. However, the history of its origin and utilization in China remains highly ambiguous. Drawing upon the most recent results of taxonomic, genetic, archeological and textual studies focused on the wheat in prehistory, this paper argues that wheat was not domesticated but introduced into China in the late fifth millennium BP. In the subsequent centuries, this exotic crop was quickly utilized as a staple food in northwest China. In contrast, it was not adopted as a staple in the Central Plains until the Han Dynasty (202 BCE–220 CE), which was mainly as a consequence of the living environment, population and innovations in food processing technology.  相似文献   
14.
近年来,随着国家农业信息化进程的不断推进,在农业领域应用多传感器数据融合技术越来越受到学者们的重视。生猪养殖是湖南省的传统优势产业,研究生猪养殖环境监测多传感器数据融合技术,有利于提高我省生猪养殖的信息化、科学化水平。本文以对生猪养殖环境的监测为研究背景,对猪舍中温度、湿度、氨气浓度、二氧化碳浓度进行实时监测,利用提出的两级多传感器数据融合模型对观测数据进行融合,最终得到对实验猪舍实际情况的综合判断,并给出相应的环境调控意见,保证生猪能在适宜的环境中成长。  相似文献   
15.
对我国民事审前准备程序的思考   总被引:1,自引:0,他引:1  
我国民事审前准备程序最大的问题是缺乏独立性,传统的"调解型"审判方式是改革的最大障碍。应在平衡程序正当性与效率性价值、审前程序独立性与庭审实质性的基础上,从完善审前证据交换制度入手,实现"调审分离"。  相似文献   
16.
本文谨从刑事证据审查判断概念及与相关概念的关系等方面入手,着重分析司法实践中对刑事证据审查判断的内容、方法、原则,进而对单个证据及全案证据的审查判断标准及法定证据的具体审查判断作出阐述。  相似文献   
17.
为解决土地适宜性评价中因子权重选取的主观性和随意性问题,以夏橙产区为例,引入模糊证据权法.评价结果显示:85%的已知适宜点处于修正后验概率分级图的中等适宜级别以上,表明集数据驱动和知识驱动为一体的模糊证据权法与修正后验概率模型结合可以客观、准确地对土地进行适宜性评价.  相似文献   
18.
Unexpected adverse preclinical findings (APFs) are not infrequently encountered during drug development. Such APFs can be functional disturbances such as QT prolongation, morphological toxicity or carcinogenicity. The latter is of particular concern in conjunction with equivocal genotoxicity results. The toxicologic pathologist plays an important role in recognizing these effects, in helping to characterize them, to evaluate their risk for man, and in proposing measures to mitigate the risk particularly in early clinical trials. A careful scientific evaluation is crucial while termination of the development of a potentially useful drug must be avoided. This first part of the review discusses processes to address unexpected APFs and provides an overview over typical APFs in particular classes of drugs. If the mode of action (MoA) by which a drug candidate produces an APF is known, this supports evaluation of its relevance for humans. Tailor-made mechanistic studies, when needed, must be planned carefully to test one or several hypotheses regarding the potential MoA and to provide further data for risk evaluation. Safety considerations are based on exposure at no-observed-adverse-effect levels (NOAEL) of the most sensitive and relevant animal species and guide dose escalation in clinical trials. The availability of early markers of toxicity for monitoring of humans adds further safety to clinical studies. Risk evaluation is concluded by a weight of evidence analysis (WoE) with an array of parameters including drug use, medical need and alternatives on the market. In the second part of this review relevant examples of APFs will be discussed in more detail.  相似文献   
19.
Most veterinarians continue to recommend anthelmintic treatment programmes for horses that derive from knowledge and concepts more than 40 years old. However, much has changed since these recommendations were first introduced and current approaches routinely fail to provide optimal or even adequate levels of parasite control. There are many reasons for this. Recent studies demonstrate that anthelmintic resistance in equine parasites is highly prevalent and multiple‐drug resistance is common in some countries, but few veterinarians take this into account when making treatment decisions or when recommending rotation of anthelmintics. Furthermore, the current approach of treating all horses at frequent intervals was designed specifically to control the highly pathogenic large strongyle, Strongylus vulgaris. But this parasite is now quite uncommon in managed horses in most of the world. Presently, the cyathostomins (small strongyles) are the principal parasitic pathogens of mature horses. The biology and pathogenesis of cyathostomins and S. vulgaris are very different and therefore require an entirely different approach. Furthermore, it is known that parasites are highly over‐dispersed in hosts, such that a small percentage of hosts harbour most of the parasites. The common practices of recommending the same treatment programme for all horses despite great differences in parasite burdens, recommending prophylactic treatment of all horses without indication of parasitic disease or knowing what species of parasites are infecting the horses, recommending use of drugs without knowledge of their efficacy and failing to perform diagnostic (faecal egg count) surveillance for estimating parasite burdens and determining treatment efficacy, are all incompatible with current standards of veterinary practice. Consequently, it is necessary that attitudes and approaches to parasite control in horses undergo a complete overhaul. This is best achieved by following an evidence‐based approach that takes into account all of these issues and is based on science, not tradition.  相似文献   
20.
基于证据理论和可变模糊集的成都市洪灾风险评估   总被引:1,自引:1,他引:0  
洪灾系统的高维性和不确定性,给灾害风险评估带来较多困难,为了提高评估的准确性和合理性,实现科学灾害管理,该文将Dempster_Shafer证据理论应用到洪水灾害风险评估中,同时利用可变模糊集理论来构造证据理论基本信任分配,实现了客观合理的证据建模,最后利用经典组合原理进行证据组合。以成都市区2012年风险等级的计算为例,风险为高等级时的信任区间为[0,0.52],似然区间为[0,0.54],不确定大小为0.019,根据判断规则,确定市区2012年的洪灾风险等级为高。基于此方法采用相同处理,对研究区成都市风险等级的时空分布进行了计算分析。结果表明该方法能够较好地融合洪水灾害系统各方面信息以及处理风险评估中的不确定性,实现了洪灾风险的准确评估。  相似文献   
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