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101.
水雷对舰船的毁伤概率计算模型及仿真 总被引:1,自引:0,他引:1
水雷障碍的作战效能研究是目前研究的重点.基于具有机动能力的水雷的特点,综合考虑了水雷障碍中水雷的布放成功率、命中概率、水雷的可靠度和动作概率等主要因素对目标舰船毁伤概率的影响,提出了目标舰船航线的选择服从均匀分布时和目标舰船航向服从正态分布时的目标舰船遭遇水雷概率计算模型,建立了基于具有机动能力水雷对目标舰船的毁伤概率模型,并进行了仿真验证,具有较高的实用性. 相似文献
102.
103.
为有效控制药房托管的药品物流运营成本,本文首先结合时空网络架构,将托管药房的药品物流调度过程描绘成一种多层时空网络,继而将研究问题构建为优化领域中的多重货物网络流问题.在此基础上,综合考虑药品物流调度过程中的需求不确定性、配送服务时间不确定性以及药品供应成本的可变性,建立基于药房托管模式的药品物流调度随机优化模型并设计具有挑选规则的混合遗传算法进行求解.参数测试表明,当挑选判断系数设为0.6时,求解算法可以收敛到比较理想的解;算例分析表明,本文所设计的随机优化模型在各决策回合的解与完全信息模型解之间的逼近程度不一,但总误差仅为0.56%;敏感性分析则发现药房最低安全库设置存在一个最优均衡点. 相似文献
104.
Product diffusion refers to the phenomenon that the later demand is dependent on the early sales. To investigate how a firm’s advance selling strategy is affected by the effect of product diffusion, we consider a monopolist seller who sells a fashionable product in a market that comprises of myopic and strategic consumers over two periods (i.e., the advance selling season and the regular selling season). For a linear product diffusion effect we find that, when the effect of product diffusion is positive, the seller may set an extremely high advance selling price to induce the strategic consumers to purchase in the regular selling season, which is counter-intuitive. Moreover, the optimal procurement quantity for the seller may increase in the negative effect of product diffusion and decrease in the amount of strategic consumers. When we extend our model to consider a concave quadratic product diffusion effect, however, the optimal procurement quantity is concave in the amount of strategic consumers. Numerical studies are further presented to discuss the managerial insights. 相似文献
105.
Dual hesitant fuzzy set (DHFS) is a new generalization of fuzzy set (FS) consisting of two parts (i.e., the membership hesitancy function and the non-membership hesitancy function), which confronts several different possible values indicating the epistemic degrees whether certainty or uncertainty. It encompasses fuzzy set (FS), intuitionistic fuzzy set (IFS), and hesitant fuzzy set (HFS) so that it can handle uncertain information more flexibly in the process of decision making. In this paper, we propose some new operations on dual hesitant fuzzy sets based on Einstein t-conorm and t-norm, study their properties and relationships and then give some dual hesitant fuzzy aggregation operators, which can be considered as the generalizations of some existing ones under fuzzy, intuitionistic fuzzy and hesitant fuzzy environments. Finally, a decision making algorithm under dual hesitant fuzzy environment is given based on the proposed aggregation operators and a numerical example is used to demonstrate the effectiveness of the method. 相似文献
106.
A hybrid approach of DEA (data envelopment analysis) and TOPSIS (technique for order performance (preference) by similarity
to ideal solution) is proposed for multiple criteria decision analysis in emergency management. Two DEA-based optimization
models are constructed to facilitate identifying parameter information regarding criterion weights and quantifying qualitative
criteria in TOPSIS. An emergency management case study utilizing data from the Emergency Management Australia (EMA) Disasters
Database is provided to demonstrate the feasibility of the proposed analysis procedure. 相似文献
107.
A digraph D(V, E) is said to be graceful if there exists an injection f : V(G) →{0, 1,... , |E|} such that the induced function f' : E(G) --~ {1, 2,… , |E|} which is defined by f' (u, v) = [f(v) - f(u)] (rood |E|+ 1) for every directed edge (u, v) is a bijection. Here, f is called a graceful labeling (graceful numbering) of D(V, E), while f' is called the induced edge's graceful labeling of D. In this paper we discuss the gracefulness of the digraph n- Cm and prove that n. Cm is a graceful digraph for m = 15, 17 and even 相似文献
108.
Spectral Properties and Positivity of Flows in Infinite Networks with Dynamic Boundary Control Nodes
Xuelian Jin Fu Zheng Ming Fang Chao Gao 《系统科学与信息学报》2009,7(4):319-325
In this paper we study transport processes on infinite networks with dynamic boundary control nodes. These flows can be modeled by operator semigroups on a suitable Banach space. Using functional analytical and graph theoretical methods, we investigate its spectral properties of the system and positivity of the semigroup under appropriate assumptions on the network. 相似文献
109.
集中式多传感器无极联合概率数据互联算法 总被引:1,自引:1,他引:1
针对杂波环境下非线性系统中的多传感器多目标跟踪问题,提出了一种集中式多传感器无极联合概率数据互联算法。该算法中,首先采用无极卡尔曼滤波器实现非线性系统中状态分布的传递,在此基础上应用联合概率数据的思想将单个传感器的量测点迹与航迹互联,最后推广至顺序结构。由于无极卡尔曼滤波器可以获得比扩展卡尔曼滤波算法更高精度的近似,因此能减少非线性模型线性化引起的近似误差对联合概率数据互联概率及状态估计的影响,与基于扩展卡尔曼滤波器思想的顺序多传感器联合概率数据互联算法相比,该算法具有更高的跟踪精度和稳定性,最后通过仿真结果验证了该算法的优越性。 相似文献
110.
Closed circle DNA algorithm of change positive-weighted Hamilton circuit problem 总被引:2,自引:0,他引:2 下载免费PDF全文
Chain length of closed circle DNA is equal. The same closed circle DNA's position corresponds to different recognition sequence, and the same recognition sequence corresponds to different foreign DNA segment, so closed circle DNA computing model is generalized. For change positive-weighted Hamilton circuit problem, closed circle DNA algorithm is put forward. First, three groups of DNA encoding are encoded for all arcs, and deck groups are designed for all vertices. All possible solutions axe composed. Then, the feasible solutions axe filtered out by using group detect experiment, and the optimization solutions are obtained by using group insert experiment and electrophoresis experiment. Finally, all optimization solutions are found by using detect experiment. Complexity of algorithm is concluded and validity of DNA algorithm is explained by an example. Three dominances of the closed circle DNA algorithm are analyzed, and characteristics and dominances of group delete experiment axe discussed. 相似文献