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An algorithm was developed with optimizable parameters to match sounds from individual insects in grain by cross-correlating signals from an acoustic sensor array. The algorithm was optimized in a series of trials conducted in the sample chamber of an Acoustic Location ‘Fingerprinting’ Insect Detector (ALFID). The sample chamber was filled with uninfested wheat, except for a single kernel, which was infested with an immature rice weevil. This kernel was placed at a known location in the sample chamber. With analysis parameters optimized, the algorithm successfully detected the single insect in 100% of the trials. The algorithm's capability to count multiple insects was assessed by combining signals in data files collected from single insects into a set that represented sounds from a pair of insects. In these analyses, the algorithm correctly detected the two insects in 100% of combinations three sensor spacings apart, 100% of combinations two sensor spacings apart, and 70% of combinations one sensor spacing apart. Based on these results and the dimensions of the ALFID sampling chamber, the algorithm has a 90% probability of identifying two randomly located insects producing sounds in a wheat sample. 相似文献
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Solutions to quality control by lot sampling through the game theory approach are presented, and the results are compared with those obtained by the classical statistical method. Single and double plans are considered and modeled as two-person zero-sum games, and optimal solutions are found. Most of the solutions are reminiscent of known statistical results and reinforce them by adding new features. 相似文献
105.
An ideal way of obtaining an optimal inspection permutation for a system with components connected in series
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Honest Walter Chipoyera 《商业与工业应用随机模型》2016,32(6):825-835
The problem of an inspection permutation or inspection strategy (first discussed in a research paper in 1989 and reviewed in another research paper in 1991) is revisited. The problem deals with an N‐component system whose times to failure are independent but not identically distributed random variables. Each of the failure times follows an exponential distribution. The components in the system are connected in series such that the failure of at least one component entails the failure of the system. Upon system failure, the components are inspected one after another in a hierarchical way (called an inspection permutation) until the component causing the system to fail is identified. The inspection of each component is a process that takes a non‐negligible amount of time and is performed at a cost. Once the faulty component is identified, it is repaired at a cost, and the repair process takes some time. After the repair, the system is good as new and is put back in operation. The inspection permutation that results in the maximum long run average net income per unit of time (for the undiscounted case) or maximum total discounted net income per unit of time (for the discounted case) is called the optimal inspection permutation/strategy. A way of determining an optimal inspection permutation in an easier fashion, taking advantage of the improvements in computer software, is proffered. Mathematica is used to showcase how the method works with the aid of a numerical example. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
106.
通过对2004—2014年的潍坊市GDP及影响因素的数据进行分析,建立EGM预测模型,利用通过检测的模型对潍坊市GDP及相关影响因素进行平均增速测算和分析,预测未来五年的发展情况,并进行了比较,结果符合实际情况,同时与其他预测模型相比较具有误差小,预测结果准确的特点,方法科学合理,具有一定的理论依据,为制定潍坊市发展的相关政策提供数据参考. 相似文献
107.
考虑不完全检测的冲击模型最优维修策略 总被引:1,自引:0,他引:1
针对制造系统中设备检测不完全的情形,研究基于不完全检测的冲击模型的周期检测、维修联合策略.通过定期检测获知系统的劣化状态以进行必要的预防性维修.在假设系统是退化的且有k个不同故障状态的条件下,以最小化系统运行成本为目标,以检测周期T、系统更换前故障次数Ⅳ为联合决策变量,利用更新过程理论建立了系统平均费用率C(T,N)的数学模型,并且给出最优联合策略的数值算法.最后借助数值例子演示了该模型,分析了检测水平对系统运行成本的影响. 相似文献
108.
利用成像光谱可同时获得水果的成像信息和光谱信息,实现水果外部和内部品质的高精度、无损伤、无污染的大面积瞬态检测。为了获得水果的成像光谱,设计了一种以自主研发的凸面光栅作为核心元件的小型成像光谱仪,它具有成像质量好、体积小、重量轻等优点,光谱分辨率在578nm波长处达2.1nm,光谱谱线弯曲和色畸变均小于0.6%。对该小型成像光谱仪进行了检测和苹果成像光谱测量实验,结果表明:该成像光谱仪满足设计要求且可以快速的获得苹果的高精度成像光谱,从而进行水果的品质检测。 相似文献
109.
Ali Azadeh Mohamad Sadegh Sangari Alireza Shamekhi Amiri 《Applied Mathematical Modelling》2012,36(4):1455-1464
Implementing efficient inspection policies is much important for the organizations to reduce quality related costs. In this paper, a particle swarm optimization (PSO) algorithm is proposed to determine the optimal inspection policy in serial multi-stage processes. The policy consists of three decision parameters to be optimized; i.e. the stages in which inspection occurs, tolerance of inspection, and size of sample to inspect. Total inspection cost is adopted as the performance measure of the algorithm. A numerical example is investigated in two phases, i.e. fixed sample size and sample size as a decision parameter, to ensure the practicality and validity of the proposed PSO algorithm. It is shown that PSO gives better results in comparison with two other algorithms proposed by earlier works. 相似文献
110.
Andrey L. Gusev 《Statistics & probability letters》2012,82(2):303-307
In this article we consider continuous inspection plans (inspection stopping plans) as recurrent events in the sequence of investigation outcomes (steps of inspection). Along with traditional continuous inspection plans, it is the first time we consider plans of continuous inspection with memory which memorize the result of the last step of inspection after the inspection is stopped. For a wide range of plans of both traditional continuous inspection and continuous inspection with memory, we have obtained the main characteristics, i.e. mathematical expectation of the number of inspected objects before the inspection is stopped and variance. 相似文献