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81.
82.
Jing-Wei Liu Ching-Hsue Cheng Yao-Hsien Chen Tai-Liang Chen 《Expert systems with applications》2010,37(1):610-617
Business operation performance is related to corporation profitability and directly affects the choices of investment in the stock market. This paper proposes a hybrid method, which combines the ordered weighted averaging (OWA) operator and rough set theory after an attribute selection procedure to deal with multi-attribute forecasting problems with respect to revenue growth rate of the electronic industry. In the attribute selection step, four most-important attributes within 12 attributes collected from related literature are determined via five attribute selection methods as the input of the following procedure of the proposed method. The OWA operator can adjust the weight of an attribute based on the situation of a decision-maker and aggregate different attribute values into a single aggregated value of each instance, and then the single aggregated values are utilized to generate classification rules by rough set for forecasting operation performance.To verify the proposed method, this research collects the financial data of 629 electronic firms for public companies listed in the TSE (Taiwan Stock Exchange) and OTC (Over-the-Counter) market in 2004 and 2005 to forecast the revenue growth rate. The results show that the proposed method outperforms the listing methods. 相似文献
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基于粗糙集理论对推理通道问题进行了研究。通过采用属性约简和属性值约简方法对数据库中的数据进行处理。在属性值约简基础之上,采用一种改进算法找出了数据库中推理规则集。进一步,将推理规则集中属性频率高的属性安全级别提高至决策属性的安全级别,从而消除推理通道。最后通过一个实例表明提出的消除通道算法是有效的。 相似文献
85.
介绍中文文本分类的流程及相关技术。在分析传统的文本特征选择不足的基础上,提出了基于粗糙集与集成学习结合的文本分类方法,通过粗糙集进行文本的特征选择,采用一种集成学习算法AdaBoost.M1来提高弱分类器的分类性能,对中文文本进行分类。实验证明,这种算法分类结果的F1值比C4.5、kNN分类器都高,具有更加优良的分类性能。 相似文献
86.
A two-legged robot will have to generate its near-optimal gaits after ensuring maximum dynamic balance margin and minimum power consumption, while moving on the rough terrains containing some staircases and sloping surfaces. Moreover, the changes of joint torques should lie below a pre-specified small value to ensure its smooth walking. The balance of the robot and its power consumption are also dependent on hip trajectory and position of the masses on various limbs. Both neural network- and fuzzy logic-based gait planners have been developed for the same, the training of which are provided using a genetic algorithm off-line. Once optimized, the planners are found to generate optimal gaits of the two-legged robot successfully for the test cases. 相似文献
87.
Vo-Gia Loc Ig Mo Koo Duc Trong Tran Sangdoek Park Hyungpil Moon Hyouk Ryeol ChoiAuthor vitae 《Robotics and Autonomous Systems》2011,59(12):1036-1048
This paper presents a study on improving the traversability of a quadruped walking robot in 3D rough terrains. The key idea is to exploit body movement of the robot. The position and orientation of the robot are systematically adjusted and the possibility of finding a valid foothold for the next swing is maximized, which makes the robot have more chances to overcome the rough terrains. In addition, a foothold search algorithm that provides the valid foothold while maintaining a high traversability of the robot, is investigated and a gait selection algorithm is developed to help the robot avoid deadlock situations. To explain the algorithms, new concepts such as reachable area, stable area, potential search direction, and complementary kinematic margin are introduced, and the effectiveness of the algorithms is validated via simulations and experiments. 相似文献
88.
属性约筒是粗糙集理论的重要研究内容之一,以浓缩树结构存储区分矩阵中的非空数据项,对IReductBtree算法进行了一些改进.它是根据树结构特点结合特殊的启发式策略,删除树中结点,直到树空最后得到信息系统的一个约简.最后,通过一个实例完整演示了该方法证实其有效性. 相似文献
89.
Agents’ model of uncertainty 总被引:4,自引:4,他引:0
Multi-agent systems play an increasing role in sensor networks, software engineering, web design, e-commerce, robotics, and
many others areas. Uncertainty is a fundamental property of these areas. Agent-based systems use probabilistic and other uncertainty
models developed earlier without explicit consideration of agents. This paper explores the impact of agents on uncertainty
models and theories. We compare two methods of introducing agents to uncertainty theories and propose a new theory called
the agent-based uncertainty theory (AUT). We show advantages of AUT for advancing multi-agent systems and for solving an internal
fundamental question of uncertainty theories, that is identifying coherent approaches to uncertainty. The advantages of AUT
are that it provides a uniform agent-based representation and an operational empirical interpretation for several uncertainty
theories such as rough set theory, fuzzy sets theory, evidence theory, and probability theory. We show also that the introduction
of agents to intuitionist uncertainty formalisms can reduce their conceptual complexity. To build such uniformity the AUT
exploits the fact that agents as independent entities can give conflicting evaluations of the same attribute. The AUT is based
on complex aggregations of crisp (non-fuzzy) conflicting judgments of agents. The generality of AUT is derived from the logical
classification of types (orders) of conflicts in the agent populations. At the first order of conflict, the two agent populations
are disjoint and there is no interference of logic values assigned to any statement p and its negation by agents. The second order of conflict models superposition (interference) of logic values for overlapping
agent populations where an agent assigns conflicting logic values (true, false) to the same attribute simultaneously.
相似文献
Boris KovalerchukEmail: |
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