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91.
The conflicts of product design are difficult to be resolved using the model of distributed constraint satisfaction problem for the characteristics of hierarchy, distribution and dynamic of product design’s constraints. Product design is translated into a granular world in quotient space, and a multi-level hierarchical model of granular computing for conflict resolution in product design is constructed. The conflicts of product design can be resolved hierarchically and progressively through granulation and division of product design’s constraints and combination between quotient mapping and granularity synthesis which can achieve the mapping and backdate between different design domains. The method resolves the problem in a hierarchical coarse-to-fine and layer by layer manner. By the granular computing for conflict resolution, the distributed constraint satisfaction problems can be simplified and the computing complexity of the problem solving can be decreased, and it has the characteristics of systematicity, integrity and hierarchy.  相似文献   
92.
Semi-domestic reindeer (Rangifer tarandus) are the main prey for lynx (Lynx lynx) in northern Scandinavia. This causes large, but poorly documented, losses of reindeer. Although the compensation schemes differ between Norway and Sweden, there is a legal requirement in both Scandinavian countries that losses of semi-domestic reindeer to large carnivores should be fully compensated. The current level of compensation payment is based on limited data on lynx kill rates on reindeer. The main goal of this study was to quantify lynx kill rates on reindeer across a range of ecological conditions in northern Scandinavia. A total of 35 lynx were monitored during 3667 days. All lynx individuals killed reindeer. However, we observed a high variation in individual kill rates. Kill rates were strongly affected by sex and social status (i.e. females with and without kittens), as well as season and reindeer availability. The highest kill rates were observed in summer for male lynx, and the lowest were observed during winter for solitary lynx at low reindeer density. In summer, several female lynx switched completely to small prey species even at high densities of reindeer. The present political goals for lynx conservation in Scandinavia require that lynx occur in the reindeer husbandry area where reindeer are the only suitable ungulate prey available. Accordingly, it is therefore impossible to have the total prevention of depredation as a management goal. Rather depredation levels must be limited such that they are considered acceptable, and fair compensation payments should be paid. Our study is the first empirical quantification of the magnitude of lynx depredation on semi-domestic reindeer. This is an important step necessary to enable the setting of fair compensation levels and will hopefully lead to a reduction in conflict level concerning the potential impacts that lynx have on reindeer.  相似文献   
93.
The purpose of this experiment was to establish behavioral indexes of piglet welfare. Forty‐eight piglets were allocated to either four indoor pens or four outdoor pens (six piglets per pen). The indoor system was a commercial pen that consisted of a concrete floor and a slat floor. The outdoor system had a dirt paddock with a wooden hutch. Growth performance, salivary cortisol levels, skin lesions and behaviors of the piglets were monitored for 4 weeks. Sixteen types of behaviors were recorded by using 2‐min instantaneous scan sampling for 8 h/day. Growth performance and salivary cortisol levels did not significantly differ between the two housing systems. On the other hand, skin lesions and behaviors were significantly affected by the housing system. The number of skin lesions was higher in the indoor system. In addition, piglets in the outdoor system showed more investigative and social‐play behaviors than those in the indoor system. Piglets in the indoor system showed more resting, drinking, moving, fighting, and conflict behaviors than those in the outdoor system. We conclude that investigative, social‐play and conflict behaviors may be effective indexes of the welfare level of piglets, especially investigative and conflict behaviors.  相似文献   
94.
采用事件相关电位技术(ERP),探讨了具有两个叉的三叉戟不可能图形加工的脑内时程动态变化,结果表明:首先在250~310ms事件窗口内,与PC(不可能条件,Possible Condition)相比,IC(可能条件,Impossible Condition)诱发了一个更正的波形(P250~310),对差异波(IC—PC)进行偶极子溯源分析,结果显示,P250~310可能起源于海马旁回.因此,P250~310可能与知觉加工过程中,将物体的各个分散特征,整合成空间上相关的物体表征的过程有关;其次,在400~500ms时间窗口内,IC比PC诱发了一个更负的波形,对差异波(IC—PC)进行偶极子溯源分析,结果显示,N400~500可能起源于扣带前回(anterior cingulate cortex,ACC)和右侧颞叶(temporallobe),因此,N400~500可能与认知冲突(不可能图形中所包含的空间结构与个体三维知识经验相违背)的监测与控制有关;最后,在500~600ms时间窗口内,IC比PC诱发了一个更正的波形(P500~600),此波形可能与工作记忆中对不可能图形的空间结构的推测有关(通过空间结构推理,...  相似文献   
95.
通过文献资料和逻辑分析,剖析了当代体育转型发展特点以及所面临的制度冲突,从而为制度变革提供建议。研究认为:中国当代体育转型在理念中面临“务民生”和“金牌政绩”的冲突;在结构中面临“群众体育突显”和“竞技体育偏重”的冲突;在主体中面临着“多元主体参与”和“单一政府管控”的冲突。而要实现“体育为民”的发展理念,成为体育强国,必须进行制度的变革。首先应该构建以群众体育为基础、竞技体育为动力、体育产业为提升的联动发展格局。其次,形成政府主导、社会参与、市场调节的多元发展主体,强化政府公共服务能力,提升社会组织独立服务能力,增强市场丰富供给能力。  相似文献   
96.
习惯法是中国固有法资源的重要组成部分,在中国乡土社会有着深厚的文化根基,发挥着独特的价值功能。在中国法治建设中,习惯法与国家法有其冲突的一面,也有其一致性,应寻求习惯法与国家法的相互妥协与合作。  相似文献   
97.
The identification of priority sites that ensure the achievement of conservation goals is key to direct conservation efforts. An estimation of the level of vulnerability of each priority area allows the identification of sites that need urgent conservation action. We present a systematic reserve selection for 1654 African mammals and amphibians that uses habitat suitability models as estimates of the area occupied by each species. These are based on the geographic range and habitat preferences for each species, which we collected in the framework of the World Conservation Union (IUCN) Global Amphibian Assessment and IUCN Global Mammal Assessment. Our results showed that in addition to existing protected areas, approximately 2.8 million km2 of land is irreplaceable to achieve the protection of 10% of the area occupied by all amphibians and mammals. This figure is higher than previous estimates from other studies. Most irreplaceable sites are located in the sub-Saharan region. More than half (55%) of the irreplaceable sites have high human population density; for only 17% the human population density is low. African amphibians and mammals have therefore to be conserved in densely populated areas where innovative management policies will be required to accommodate conservation successfully.  相似文献   
98.
邱国强    牛潜  吴振华  郭珊珊  秦琳  汪应宏 《水土保持研究》2022,29(4):400-406+414
为了探究城镇建设用地扩张对土地利用冲突的影响,以城镇化水平快速提高的苏锡常地区为例,基于1990—2018年土地利用分类数据,采用景观风险评价方法,通过计算空间的外部压力、脆弱性及稳定性指数构建土地利用冲突综合测度模型,借鉴倒“U”型理论,将空间冲突分为稳定可控、基本可控、基本失控和严重失控4种类型,对苏锡常地区空间冲突水平进行了评估。结果表明:(1)近30年来,苏锡常地区整体空间冲突水平以可控类型为主,但冲突强度呈现上升趋势,1990—2018年平均冲突指数由0.269增长至0.418,近1.55倍;(2)不同用地类型的空间冲突强度存在差异,林草地和水域空间冲突水平较低,建设用地空间冲突水平最高且失控类型在1990—2018年提升了14.3%,有进一步激化扩散趋势;(3)土地利用冲突存在空间相互关系,高—高值在苏、锡、常市中心区及江阴、张家港、常熟、昆山市集聚,低—低值则主要分布在西部溧阳市山地及水域周边。研究结果可为有效识别苏锡常地区土地利用冲突,优化区域发展模式提供理论参考。  相似文献   
99.
[目的]探析新疆乌鲁木齐市“三生”用地变化及其引起的空间冲突变动,为该地区的土地资源优化配置提供参考依据。[方法]利用外部压力、脆弱性和稳定性3个因子构建格网尺度下的空间冲突测度模型,对该地区2000—2018年空间冲突时空分异特征进行定量评价。[结果](1)2000—2018年,乌鲁木齐市北部为城市生活用地的主要增长方向,农业生产用地空间格局呈现破碎化趋势,生态用地是乌鲁木齐市三生用地的主要组成部分,应避免人类活动对新增核心生态用地的占用。(2)各个时期乌鲁木齐市“三生”空间冲突等级均表现为:稳定可控>轻度冲突>中度冲突>重度冲突。(3)重度冲突空间单元增幅最大,表明乌鲁木齐市重度冲突失控的地区范围有扩大的趋势。这应是乌鲁木齐市空间冲突调控的重点区域。(4)不同空间类型的空间冲突存在一定差异。乌鲁木齐市冲突强度从大到小依次为:生产空间>生活空间>生态空间。[结论]乌鲁木齐市“三生”用地变化与区域经济社会发展具有较强的吻合性,未来应逐步改变生活空间过速扩张而导致冲突水平逐渐增强的现象。应更加重视城市生活用地的动态监测,保护核心生态用地,以实现“三生”用地更...  相似文献   
100.
Ofer Gon 《African Zoology》2013,48(4):321-322
Eight postlarvae of Cygnodraco mawsoni Waite, 1916, were collected off the Australian Antarctic Mawson Station in the South Indian Ocean, during the South African SIBEX II expedition. These postlarvae are distinctive by having a long and slender body, projecting lower jaw and bicoloured caudal fin. Their morphology and pigmentation are unlike any known bathydraconid early life history stages.  相似文献   
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