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排序方式: 共有77条查询结果,搜索用时 921 毫秒
1.
This work proposes a Progressive Assisted Sorting Algorithm (PASA) based on a multicriteria evaluation ELECTRE-type method.
The purpose of the PASA is to aid a decision maker to progressively sort a set of alternatives into a set of categories, which
we considered are ordered (ordinal sorting), following a consistency principle. We consider the principle that if an alternative
outranks (is as good as) a second one, then it must belong to the same category or to a better category. The set of alternatives
already sorted by the decision maker will implicitly define the categories, and will constrain the range of categories where
other alternatives may be sorted. We show how the same idea may be used in an aggregation/disaggregation approach, considering
some parameters of ELECTRE are not fixed a priori, but are constrained only by the examples provided. In this context, we
establish a “convex-shape property” stating that the range of possible categories for an alternative is always an interval
of categories. A discussion contrasting this approach with ELECTRE TRI is included in the conclusions. 相似文献
2.
Sorting tags are oligomeric structures that can be used as protecting groups or chiral auxiliaries enabling solution-phase mixture syntheses of multiple tagged compounds in one pot and allowing for facile and predictable chromatographic separation of products at the end of synthetic sequences. Perfluorinated hydrocarbon and oligomeric ethylene glycol (OEG) derivatives are known classes of sorting tags. Herein we describe the preparation of OEGylated chiral oxazolidinones and their use in asymmetric solution-phase mixture aldol reactions. Through the use of such oxazolidinones based on tyrosine four different individually tagged aldol adducts were obtained as a mixture, chromatographically demixed, detagged, and it was shown that these processes gave the desired aldol products in good yield and enantioselectivity. 相似文献
3.
为更准确地评价水环境质量,将端点三角白化权函数灰色评估引入到水质综合评价中.针对以往灰色白化权函数评估主要通过测定指标灰聚类系数判定被评价对象的优劣强弱等级进行等级识别评价,对三角白化权函数计算方法进一步扩展,完成多评价对象的准确等级定位及比较排序.将这种方法应用于山东省聊城市东昌湖水水质评价中,经实例计算证明基于三角白化权函数灰色评估评价模型的稳定性、合理性和实用性为水质评价研究方法提供了新的思路和借鉴. 相似文献
4.
太阳能电池测试分选设备是晶体硅太阳能电池生产专用设备,可用于太阳能电池转换效率以及电性能参数测量。所有的测量结果可以自动分类,自动保存。该设备在测试系统设计、分选结构设计、步进电机精密驱动、高速数据交换和电气控制等技术方面达到较高水平。该设备具有全自动化,操作简便,测试精确,运行稳定,碎片率低、生产效率高等特点,性能完... 相似文献
5.
Multiobjective optimization scheme for industrial synthesis gas sweetening plant in GTL process
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In industrial amine plants the optimized operating conditions are obtained from the conclusion of occurred events and challenges that are normal in the working units. For the sake of reducing the costs, time consuming, and preventing unsuitable accidents, the optimization could be performed by a computer program. In this paper, simulation and parameter analysis of amine plant is performed at first. The optimization of this unit is studied using Non-Dominated Sorting Genetic Algorithm-II in order to produce sweet gas with CO 2 mole percentage less than 2.0% and H 2 S concentration less than 10 ppm for application in Fischer-Tropsch synthesis. The simulation of the plant in HYSYS v.3.1 software has been linked with MATLAB code for real-parameter NSGA-II to simulate and optimize the amine process. Three scenarios are selected to cover the effect of (DEA/MDEA) mass composition percent ratio at amine solution on objective functions. Results show that sour gas temperature and pressure of 33.98 ? C and 14.96 bar, DEA/CO 2 molar flow ratio of 12.58, regeneration gas temperature and pressure of 94.92 ? C and 3.0 bar, regenerator pressure of 1.53 bar, and ratio of DEA/MDEA = 20%/10% are the best values for minimizing plant energy consumption, amine circulation rate, and carbon dioxide recovery. 相似文献
6.
重频分选方法中,由于序列差值直方图法(SDIF)对PRI抖动的雷达脉冲信号的分选能力差,而PRI变换法可以分选PRI抖动的雷达脉冲信号,但是运算量太大,难以实现实时分选。对SDIF算法进行了改进,采用交叠PRI箱的方法进行直方图的统计,使得改进后的SDIF在运算量增加不多的情况下,可以实时较好地分选PRI抖动量在10%以内的雷达脉冲信号。 相似文献
7.
设计一种由PLC控制的自动物料分拣装置,由旋转编码器检测定位,通过漫射式光电传感器、光纤传感器和金属传感器检测判定物料类型,利用气杆将物料推入相应物料槽中,传送带由减速电机和西门子变频器驱动,输送物料进行分拣。设计完成的物料分拣装置,分成三个槽位,完成了对黑色、白色、金属三种物料特性的检测区分和分拣工作。 相似文献
8.
一种新的按位块分段快速排序算法 总被引:1,自引:0,他引:1
针对分段快速排序法因分段映射策略不理想而造成算法复杂度显著增加之问题,文章提出了一种由按位块分段、分段映射和局部快速排序所组成的新排序算法——按位块分段快速排序法(以下简称为“按位块分段快速排序”)。算法分析和实验结果都表明:在待排序数据均匀分布或正态分布的情况下,按位块分段快速排序法的时间复杂度可以达到O(N),而附加存储空间开销却仅仅为N+M(M为分段数目,1≤M≤N),同时排序速度明显优于Quick Sort、分段快速排序、分“档”统计插入排序和Proponion Split Sort等算法。 相似文献
9.
Murat Köksalan Tayyar Büyükbaşaran Özgür Özpeynirci Jyrki Wallenius 《European Journal of Operational Research》2010
We develop a model for flexibly ranking multi-dimensional alternatives/units into preference classes via Mixed Integer Programming. We consider a linear aggregation model, but allow the criterion weights to vary within pre-specified ranges. This allows the individual alternatives/units to play to their strengths. We illustrate the use of the model by considering the Financial Times Global MBA Program rankings and discuss the implications. We argue that in many applications neither the data nor the weights or the aggregation model itself is precise enough to warrant a complete ranking, providing an argument for sorting or what we call flexible ranking. 相似文献
10.
Therese Biedl Angèle M. Hamel Alejandro López-Ortiz 《Discrete Applied Mathematics》2010,158(15):1579-1586
We consider the problem of sorting a permutation using a network of data structures as introduced by Knuth and Tarjan. In general the model as considered previously was restricted to networks that are directed acyclic graphs (DAGs) of stacks and/or queues. In this paper we study the question of which are the smallest general graphs that can sort an arbitrary permutation and what is their efficiency. We show that certain two-node graphs can sort in time Θ(n2) and no simpler graph can sort all permutations. We then show that certain three-node graphs sort in time Ω(n3/2), and that there exist graphs of k nodes which can sort in time Θ(nlogkn), which is optimal. 相似文献