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451.
"新三论"(包括耗散结构论、协同学和突变论)作为一种新的世界观,给研究作战系统这个复杂的非线性系统提供了新的视角。运用"新三论"的思想和方法指出作战系统的序参量,建立序参量方程,分析序参量演化稳定性与途径,得出一些有价值的结论,对于探索作战系统发展演变的规律具有重要意义。 相似文献
452.
平行度测量是舰船设备系统标校的前提,传统的平行度测量方法需要依赖"星"或"标"的配合,由于舰船所在位置的限制,可能不具备设置"星"或"标"的条件,利用夜空的星星也很受限。为克服环境条件对标校的限制,可以采用角速率陀螺作为传感器动态测量指向设备的平行度,推出了计算俯仰和旋回零位误差的公式,并对器件误差的影响进行了估算,计算结果说明现有的角速率陀螺器件的精度能满足本测量方法的需求。该研究成果可在舰船设备系统标校中运用,以克服传统方法依赖外界条件的难题。 相似文献
453.
Assemble‐to‐order (ATO) is an important operational strategy for manufacturing firms to achieve quick response to customer orders while keeping low finished good inventories. This strategy has been successfully used not only by manufacturers (e.g., Dell, IBM) but also by retailers (e.g., Amazon.com). The evaluation of order‐based performance is known to be an important but difficult task, and the existing literature has been mainly focused on stochastic comparison to obtain performance bounds. In this article, we develop an extremely simple Stein–Chen approximation as well as its error‐bound for order‐based fill rate for a multiproduct multicomponent ATO system with random leadtimes to replenish components. This approximation gives an expression for order‐based fill rate in terms of component‐based fill rates. The approximation has the property that the higher the component replenishment leadtime variability, the smaller the error bound. The result allows an operations manager to analyze the improvement in order‐based fill rates when the base‐stock level for any component changes. Numerical studies demonstrate that the approximation performs well, especially when the demand processes of different components are highly correlated; when the components have high base‐stock levels; or when the component replenishment leadtimes have high variability. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012 相似文献
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456.
某高性能激光测距机总体设计与分析 总被引:2,自引:0,他引:2
针对某型激光测距机的高性能要求,在总体设计中采用多发散角分档可调、恒比定时鉴别和厘米级高分辨率计数器等项技术和措施,对激光测距作用距离、回波率以及发散角选择进行详细计算,计算结果表明总体组成能满足指标要求。 相似文献
457.
高可靠性软件的极值统计分析 总被引:2,自引:1,他引:1
提出了极值统计分析的方法.对于失效数据极值分布函数的拟合检验,采用了相关系数法;对于母体分布的参数估计,则分别采用了最小二乘估计(LSE)和极大似然估计(MLE);最后通过一个实例说明了统计过程,并用模拟的方法证明了最小二乘估计较好. 相似文献
458.
We consider a supplier with finite production capacity and stochastic production times. Customers provide advance demand information (ADI) to the supplier by announcing orders ahead of their due dates. However, this information is not perfect, and customers may request an order be fulfilled prior to or later than the expected due date. Customers update the status of their orders, but the time between consecutive updates is random. We formulate the production‐control problem as a continuous‐time Markov decision process and prove there is an optimal state‐dependent base‐stock policy, where the base‐stock levels depend upon the numbers of orders at various stages of update. In addition, we derive results on the sensitivity of the state‐dependent base‐stock levels to the number of orders in each stage of update. In a numerical study, we examine the benefit of ADI, and find that it is most valuable to the supplier when the time between updates is moderate. We also consider the impact of holding and backorder costs, numbers of updates, and the fraction of customers that provide ADI. In addition, we find that while ADI is always beneficial to the supplier, this may not be the case for the customers who provide the ADI. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011 相似文献
459.
This article studies the optimal control of a periodic‐review make‐to‐stock system with limited production capacity and multiple demand classes. In this system, a single product is produced to fulfill several classes of demands. The manager has to make the production and inventory allocation decisions. His objective is to minimize the expected total discounted cost. The production decision is made at the beginning of each period and determines the amount of products to be produced. The inventory allocation decision is made after receiving the random demands and determines the amount of demands to be satisfied. A modified base stock policy is shown to be optimal for production, and a multi‐level rationing policy is shown to be optimal for inventory allocation. Then a heuristic algorithm is proposed to approximate the optimal policy. The numerical studies show that the heuristic algorithm is very effective. © 2011 Wiley Periodicals, Inc. Naval Research Logistics 58: 43–58, 2011 相似文献
460.
《孙子兵法》作为兵学圣典,对当前部队的日常管理具有重要的指导作用。从《孙子兵法》对自古以来官兵紧张关系的具体描述,剖析当前官兵关系紧张的成因,探讨科学解决官兵紧张关系的方法。 相似文献