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排序方式: 共有125条查询结果,搜索用时 46 毫秒
101.
基于蚂蚁算法的蚂蚁追踪技术是近几年发展起来的一种先进的优化算法,主要用于断裂系统自动解释技术,能够通过自定义相关参数,对目标区满足要求的大断层、小断层进行精细刻画和定量描述。在番禺30-1气田开发井的随钻过程中,应用该技术识别出了地震体和方差体中难以辨认的小断层和裂缝,分析了导致水平井钻井过程中漏失的原因,并描述了小断层、裂缝的特征,据此为钻井风险的预判提供了依据。以及为后续水平井位的优化提供有价值的参考。实钻结果证实,井位优化效果很好,充分满足了预期的设计要求。 相似文献
102.
This paper presents a method of adding label to the map especially for the point feature. This method overcomes the shortcoming of traditional methods, e.g. Conflict-Backtracking method. Its kernel algorithm use the hopfield neural network to find the best label position for point feature. The experimental results proves that this algorithm has good permanence and high speed. 相似文献
103.
《The Professional geographer》2013,65(4):451-464
In our study, 48 U.S. departments that grant geography PhDs are compared along four measures of academic productivity. Using 1980–1994 as the base period, research productivity of faculty was assessed by counting book titles, as well as authorships in 77 journals. Teaching productivity was determined by placement of PhDs in graduate programs of geography in North America, and by a weighted index of teaching outcomes. Data were summed for departments, but are reported primarily as productivity per person (per FTE count). The results point to a wide variety of departmental profiles, from those departments that appear to emphasize teaching outcomes to those that are more productive in book publishing and journal authorship, with several exhibiting a balance between teaching and research. 相似文献
104.
《The Professional geographer》2013,65(3):297-303
Analyses of agricultural growth in subsistence economies may be facilitated if agricultural intensity is viewed in terms of the concentration of production or yield per unit area and time. This view of agricultural intensity is implicit in many growth arguments and is consistent with their purpose. Limited production data from various subsistence economies necessitate the use of a surrogate measure of intensity that is based on a variety of input factors. 相似文献
105.
多协议标记交换技术是一种全瓶的网络交换技术,它的成功应用,将会解决目前IP网络上存在的众多问题。阐述了多协议标记交换技术的原理、关键技术等,并简单介绍在虚拟专用网、流量工程、Qos等方面的应用。 相似文献
106.
基于Voronoi图的点状要素注记自动配置 总被引:3,自引:1,他引:2
对点状要素候选注记位置质量进行了量化评定,提出了基于Voronoi图的点状要素注记自动配置的思想,并对其进行了实验性验证,理论及实验分析结果表明此种方法逻辑严密,简单易行,注记配置速度快、回溯次数少,超常规注记配置出现个数少,对GIS平台点状要素注记自动配置具有指导意义。 相似文献
107.
布局是VLSI物理设计的关键环节,采用了O-TREE的编码表示方法来解决在超大规模集成电路布局中,具有预定义坐标结群约束模块的布局问题(简称PCA问题)。目前,存在一些成功的算法来解决PCA问题,然而,它们的算法有些复杂,有些耗时。由此提出了一种新的布局算法来解决这个问题,该算法是基于O-TREE结构,旨在减少总的运行时间且简便。通过对MCNC的标准例子ami33和ami49上仿真实验表明:与参考文献5提到的结果相比,新算法是可行的并且很有效。它不仅使芯片面积利用率得到改善,而且节约了一半以上的时间开销。 相似文献
108.
《The Journal of geography》2012,111(3-4):132-141
Abstract This article is an overview of the agriculture section in the outline of the Advanced Placement (AP) human geography course. It is intended to provide a more detailed framework on which teachers may develop their own curriculum for the AP class. Special emphasis is given to the practice of agriculture in contemporary industrial societies. It also encourages teachers to balance the cultural and historical views of agriculture contained in many textbooks with an economic and geographic focus. Agribusiness is also given special treatment. 相似文献
109.
The optimal design and placement of controllers at discrete locations is an important problem that will have impact on the control of civil engineering structures. Though algorithms exist for the placement of sensor/actuator systems on continuous structures, the placement of controllers on discrete civil structures is a very difficult problem. Because of the nature of civil structures, it is not possible to place sensors and actuators at any location in the structure. This usually creates a non‐linear constrained mixed integer problem that can be very difficult to solve. Using genetic algorithms in conjunction with gradient‐based optimization techniques will allow for the simultaneous placement and design of an effective structural control system. The introduction of algorithms based on genetic search procedures should increase the rate of convergence and thus reduce the computational time for solving the difficult control problem. The newly proposed method of simultaneously placing sensors/actuators will be compared to a commonly used method of sensors/actuators placement where sensors/actuators are placed sequentially. The savings in terms of energy requirements and cost will be discussed. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
110.
地图汉字注记质量函数的分析与计算 总被引:2,自引:0,他引:2
提出并详细讨论了基于6条规则的地图汉字注记质量函数,给出了一个基于地图汉字注记质量函数的例子。与仅考虑注记间不应该相互压盖以及注记不压盖重要地物的结果对比发现,利用本文地图汉字注记质量函数,所得结果更好。 相似文献