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1.
基于深度学习的牛肉大理石花纹等级手机评价系统   总被引:4,自引:4,他引:0  
大理石花纹是影响牛肉品质等级的重要指标,目前中国牛肉加工企业对大理石花纹的评价是由专业分级人员参照标准图谱完成,具有主观性强、耗费人工的缺点。针对上述问题,该研究提出了基于深度学习的智能分级方法,设计一种具有4层卷积的神经网络结构,实现了大理石花纹特征的自动提取,并基于智能手机开发了牛肉大理石花纹检测软件。该研究共采集样本图像1 800张,按3:1:1分为校正集、验证集和测试集。为进一步验证模型,将该方法与传统机器视觉方法进行了比较,提取了牛肉大理石花纹的大、中、小脂肪颗粒个数,脂肪总面积和脂肪分布均匀度5个参数,并建立了多元线性回归模型。试验结果表明,该研究所用方法大理石花纹检测准确率更高,验证集检测正确率为97.67%。最后编写了手机软件,将模型移植入Android手机,在手机平台上调用模型进行大理石花纹检测。试验表明,该软件对测试集样本的检测准确率为95.56%,单张检测时间低于0.5 s。该研究结合卷积神经网络分类能力强和智能手机运行速度快等优点,开发了牛肉大理石花纹的手机评价系统,具有较好的实用性和便携性,可提高牛肉大理石花纹检测效率,有助于提高农畜产品检测的智能化水平。  相似文献   
2.
The level of artificial electromagnetic field (EMF) has steadily increased with the development of human civilization. The developing chicken embryo has been considered a good model to study the effects of EMF on living organisms. The aim of the study was to determine the effect of a 1800 MHz electromagnetic field during embryogenesis on the frequency of chick embryo malformations, morphometric parameters of the heart and liver and concentration of corticosterone in blood plasma, lipid and glycogen content in the liver of newly hatched chicks. A 1800 MHz EMF was found to shorten the duration of embryogenesis (earlier pipping and hatching of chicks) while having no effect on the quantity and quality of chicks and on increasing the incidence of embryo malformations. Exposure of chick embryos to EMF caused decreases in relative heart weight and right ventricle wall thickness. The pipping and hatching of chicks can be accelerated by stressful impact of EMF, which is confirmed by a significant increase in plasma corticosterone concentrations and decrease in fat and glycogen in the liver of chicks exposed during embryogenesis on the electromagnetic field with a frequency of 1800 MHz.  相似文献   
3.
移动通信基站基于卫星系统和通信系统的相关技术已相对成熟,在森林防火工作中已逐渐推广应用。本文根据工程实例,简要阐述了移动通信基站在森林防火工程项目中的应用。  相似文献   
4.
The mechanism of MIPv4 regional registration and the low latency handoff protocols are introduced. Ways and procedure of pre-registration handoff and post-registration handoff are discussed also. The authors analyze the performance of the low latency handoff protocols combined with low latency handoffs over a wireless access based on IEEE 802. 11 standard in a tree-like network topology. The performance of pre-registration and post-registration scheme is given by simulation.  相似文献   
5.
Some thoroughly research on the basic method for load state detection in MIN is introduced. Load sources of SCP and SSP in MIN are analyzed in detail after investigating the relationship between inter resource and load state in the system. And load detection parameters and model are presented. Moreover, a novel strategy to detect system load state based on fusion of multi detection data is presented. By some test, the theory and method are proved most feasible. Our research show that load state of MIN can be recognized by detecting utility of internal resource utilizing of single node in MIN, and multi redundant detecting data fusion is effective approach to improve the reliability and trust degree of the result.  相似文献   
6.
以全自主移动机器人为研究平台,介绍了移动机器人的硬件体系结构、避障行为决策、避障运动控制等。提出一种足球机器人避障路径规划方法,该方法吸取了栅格法信息处理量小的优点,只对障碍物的威胁点进行检测,弥补了其在特征匹配方面的不足,同时无需考虑障碍物的运动状态和运动速度,提高了机器人避障的灵活性和鲁棒性。  相似文献   
7.
新型行走式多功能灌溉机设计   总被引:1,自引:0,他引:1  
行走式多功能灌溉机是通过对行走式灌溉机的系统弹性优化配置和系统合理组配技术的创新研究,研制成功的具有适应多元化小水源和地貌特征的,集提水、运水、供水、灌溉(行灌、微灌、远射程均匀喷灌)、施药(肥)于一体的新型行走式多功能灌溉机系列产品。  相似文献   
8.
Abstract

As a state-of-the-art technology for fine-scale forest investigation, mobile terrestrial light detection and ranging (LiDAR), also referred to as mobile laser scanning (MLS), recently has been increasingly exploited to improve its performance on this task. One potential solution is to apply special MLS systems with the capability of collecting multiple echoes per pulse (multi-echoes, for short) from canopies. The methodologies of this rationale turned out to perform better but still insufficiently for canopy properties retrieval, owing to their common defective premise. That is, the knowledge of the characteristics of MLS scan data comprising multi-echoes, so far, is in shortage, especially when regarding the dynamic process of tree foliation. As a pioneering work for this challenge, this study attempted to comprehensively analyze the characteristics of MLS multi-echoes collected from tree crowns during foliation. Specifically, new stable multi-echoes-related features were deduced under the schematic frame of relative quantification, in both spatial and temporal sense. “Relative” here briefly means the division operation deployed on the attributes of multi-echoes, individually in terms of the number of echoes, echo width and crown volume integrity, between their different return orders. Then, the “relative” schematic was primarily validated for more stably representing crown properties during foliation, based on the real data that was collected by the Sensei MLS system with a maximum of three echoes per pulse. Further, a case of tree species classification was examined using a linear discriminant classifier, and it was testified that the resultant temporal statistical rules of multi-echoes as the reverse clues can enhance the performance of MLS in applications.  相似文献   
9.
作物品种田间测试是评价、筛选新品种不可或缺的关键环节,是品种大规模推广应用的主要依据。育种单位每年试验小区数量巨大,单一育种公司每年新产生大约1 000万个数据点,依靠传统的人工纸质录入效率低、错误率高。针对测试数据田间野外录入的特点,研究设计了一套高效的测试数据快速录入、及时传输的技术方案,并详细介绍了客户端与服务器数据交互融合、拍照采集条码、数据分块存取等关键技术。该系统进行了Windows Mobile 6.1及以上多个手机平台的应用测试,结果表明此方法是高效可行的。  相似文献   
10.
乌兰布和沙漠流动沙丘不同部位水分动态研究   总被引:5,自引:3,他引:5  
通过对乌兰布和沙漠流动沙丘的不同部位沙土含水量的测定研究,结果表明:(1)乌兰布和沙漠流动沙丘3个不同部位的水分垂直变化趋势是一致的,0~60cm含水量变化幅度大,60~100cm变化幅度小,含水量最大值出现在20~60CITI,降雨主要影响60cm以上的沙土水分;(2)3种部位在时间变化上都表现为4~5月含水量最小,从6月开始含水量升高;(3)迎风坡含水量较其他部位大0.65%~0.9%,较背风坡大1.8%~2.5%,其他部位较背风坡大1%~1.7%,且3种地貌部位20~60cm处较80cm和100cm处有较大差异,同时迎风坡的变化幅度最大。  相似文献   
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