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881.
Optimal decision-making model of spatial sampling for survey of China’s land with remotely sensed data 总被引:2,自引:0,他引:2
In the remote sensing survey of the country land, cost and accuracy are a pair of conflicts, for which spatial sampling is
a preferable solution with the aim of an optimal balance between economic input and accuracy of results, or in other words,
acquirement of higher accuracy at less cost. Counter to drawbacks of previous application models, e.g. lack of comprehensive
and quantitativecomparison, the optimal decision-making model of spatial sampling is proposed. This model first acquires the
possible accuracy-cost diagrams of multiple schemes through initial spatial exploration, then regresses them and standardizes
them into a unified reference frame, and finally produces the relatively optimal sampling scheme by using the discrete decision-making
function (built by this paper) and comparing them in combination with the diagrams. According to the test result in the survey
of the arable land using remotely sensed data, the Sandwich model, while applied in the survey of the thin-feature and cultivated
land areas with aerial photos, can better realize the goal of the best balance between investment and accuracy. With this
case and other cases, it is shown that the optimal decision-making model of spatial sampling is a good choice in the survey
of the farm areas using remote sensing, with its distinguished benefit of higher precision at less cost or vice versa. In order to extensively apply the model in the surveys of natural resources, including arable farm areas, this paper proposes
the prototype of development using the component technology, that could considerably improve the analysis efficiency by insetting
program components within the software environment of GIS and RS. 相似文献
882.
GAOCunchen GUOJifeng 《中国海洋大学学报(英文版)》2005,4(2):185-188
The existence of linear quadratic optimal control of ship automatic steering instruments is studied. Firstly, the sufficient conditions for the quadratic integrability of the solutions of linear second order time-variant differential equations are developed. Secondly, the optimal control form of the ship automatic steering instrument is obtained by using the dynamic programming method, which guarantees a minimal ship sway range, during long-distance navigation, by using as little energy as possible. Finally, based on the above mentioned sufficient conditions, the conditions for the realization of optimal control are obtained, which provides a foundation for choosing the weighted coefficients for optimal control in engineering. 相似文献
883.
This paper explores factors to be taken into consideration in determining the optimal exploration budget for a mining company readying itself for detail work within a mineral province. Optimal strategy is shown to be a combination of results from recent conventional reservation value stopping rules and optimal expenditure models appearing earlier in the literature. 相似文献
884.
特征提取和选择是模式识别核心问题之一,它极大地影响着分类器的设计和性能,高维的特征选择更是一个NP难题。针对特征选择这一组合优化及多目标优化问题,本文提出了改进的融合启发信息ACO(Antcolony optimization)特征选择的新方法,该算法比不用启发信息的ACO方法能更好地找出代表问题空间的最优特征子集,降低分类系统的搜索空间,从而提高搜索效率。以航空纹理影像的特征选择和分类问题为例,利用原始蚂蚁算法和改进的蚂蚁算法选择的特征分别进行识别,结果证明该算法不仅能够比没有改进的蚂蚁找出有效特征集、降低图像特征空间维数、减少图像分类的工作量,而且提高了分类识别正确率。 相似文献
885.
886.
矿产资源的最适耗竭分析 总被引:1,自引:0,他引:1
矿产资源的持续利用是可持续发展战略的重要组成部分。单纯的消耗资源和追求经济数量增长的发展模式,正严重威胁着资源的持续利用。因此,以较低的资源代价和社会代价,取得较高的经济发展水平是最适耗竭所要解决的问题。为此,本文提出了矿产资源最适耗竭发展模式。 相似文献
887.
LIN Xueyuan CHEN Yulin XU Zhibin 《地球空间信息科学学报》2007,10(1):17-21
According to the characteristic of Beidou Double-star positing system (for short: Double-star position), the optimal predication model of Double-star position/SINS integrated system is put forward, which can make use of the delayed position in-formation from Double-star positioning system to predicate optimally for the integrated system, and then to correct SINS, and af-fords integrated results of some navigation parameters. In order to validate the consistency of the filter, the criteria for consistency of a filter is also studied, and the tested statistics are given, the experiment based on practical measured data shows that the filtering method is consistent with the integrated system. 相似文献
888.
高性能稳健性的GPS卫星接收机仍然是当前研究和发展的热点。在高动态条件下,GNSS接收机设计总是涉及到跟踪动态性能所要求的环路带宽和噪声所要求的环路带宽一对矛盾体。以微惯性测量单元(MIMU)辅助的GPS接收机为实例,设计了MIMU辅助的GPS接收机搜索算法和跟踪算法,同时为减少GPS接收机对惯性器件的性能的依赖,设计了基于MIMU辅助的最优GPS接收机的环路带宽。通过仿真和车载试验对所设计的方法进行验证,仿真和试验结果表明,MIMU辅助的GPS接收机动态性能取决于MIMU的性能指标和环路的带宽,而抗干扰性能至少有13 dB的提高;跑车试验中,商用GPS接收机和研制的GPS接收机精度大体相当。同时系统还能够提供姿态角信息。 相似文献
889.
条件非线性最优扰动法在大气与海洋目标观测研究中的应用 总被引:3,自引:0,他引:3
对近年来用条件非线性最优扰动法研究大气与海洋目标观测问题的部分工作进行了总结,主要涉及厄尔尼诺-南方涛动(ENSO)事件、黑潮路径变异事件以及阻塞事件。通过研究这些事件发生的最优前期征兆(OPR)和最快增长初始误差(OGE),发现这些事件的最优前期征兆和最快增长初始误差分别具有空间的高度相似性及其伴随的局地性特征。理想回报试验表明,如果在ENSO事件和黑潮路径变异事件的最快增长初始误差和最优前期征兆所确定的扰动大值区减小初始场误差,上述事件的预报技巧会大幅度提高;最优前期征兆和最快增长初始误差的空间相似性使得在同一敏感区域增加额外观测,不仅有助于捕捉上述异常事件的前期信号,还可以有效减小初始误差,从而提高对该事件的预报技巧。阻塞事件爆发的最优前期征兆和最快增长初始误差的空间相似性和局地性特征在其目标观测研究中的应用,应该是深入研究的课题。 相似文献
890.
A Variant Constrained Genetic Algorithm for Solving Conditional Nonlinear Optimal Perturbations简 总被引:1,自引:0,他引:1
A variant constrained genetic algorithm (VCGA) for effective tracking of conditional nonlinear optimal perturbations (CNOPs) is presented. Compared with traditional constraint handling methods, the treatment of the constraint condition in VCGA is relatively easy to implement. Moreover, it does not require adjustments to indefinite pararneters. Using a hybrid crossover operator and the newly developed multi-ply mutation operator, VCGA improves the performance of GAs. To demonstrate the capability of VCGA to catch CNOPS in non-smooth cases, a partial differential equation, which has "on off" switches in its forcing term, is employed as the nonlinear model. To search global CNOPs of the nonlinear model, numerical experiments using VCGA, the traditional gradient descent algorithm based on the adjoint method (ADJ), and a GA using tournament selection operation and the niching technique (GA-DEB) were performed. The results with various initial reference states showed that, in smooth cases, all three optimization methods are able to catch global CNOPs. Nevertheless, in non-smooth situations, a large proportion of CNOPs captured by the ADJ are local. Compared with ADJ, the performance of GA-DEB shows considerable improvement, but it is far below VCGA. Further, the impacts of population sizes on both VCGA and GA-DEB were investigated. The results were used to estimate the computation time of ~CGA and GA-DEB in obtaining CNOPs. The computational costs for VCGA, GA-DEB and ADJ to catch CNOPs of the nonlinear model are also compared. 相似文献