检索结果-南通市图书馆

Minimizing Ratio of Monotone Non-submodular Functions

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of the Operations Research Society of China 2019年第3期7卷 449-459页

作者： Yi-Jing Wang Da-Chuan Xu Yan-Jun Jiang Dong-Mei Zhang Department of Information and Operations Research College of Applied SciencesBeijing University of TechnologyBeijing 100124China School of Mathematics and Statistics Science Ludong UniversityYantai 264025ShandongChina School of Computer Science and Technology Shandong Jianzhu UniversityJinan 250101China

In this paper,we investigate the problem of minimizing the ratio of normalized non-negative monotone non-submodular set function f and normalized non-negative monotone set function *** take advantage of the greedy technique and get a per-formance guarantee depending on the generalized curvature and inverse generalized curvature of f,as well as the submodularity ratio of *** results generalize the works of Bai et al.(algorithms for optimizing the ratio of submodular ***:Proceedings of the 33rd International Conference on Machine L earning,2016)and Qian et al.(Optimizing ratio of monotone set ***:Proceedings of the 26th International Joint Conference on Artificial Intelligence,2017).

关键词： Non-submodular Set functions Minimizing ratio greedy algorithm

Extraction of coastline in high-resolution remote sensing images based on the active contour model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Harbin Institute of Technology(New Series) 2011年第4期18卷 13-18页

作者：邢坤付宜利王树国韩现伟 State Key Laboratory of Robotics and System Harbin Institute of Technology

While executing tasks such as ocean pollution monitoring,maritime rescue,geographic mapping,and automatic navigation utilizing remote sensing images,the coastline feature should be *** methods are not satisfactory to extract coastline in high-resolution panchromatic remote sensing *** contour model,also called snakes,have proven useful for interactive specification of image contours,so it is used as an effective coastlines extraction ***,coastlines are detected by water segmentation and boundary tracking,which are considered initial contours to be optimized through active contour *** better energy functions are developed,the power assist of snakes becomes *** internal energy has been done to reduce problems caused by convergence to local minima,and new external energy can greatly enlarge the capture region around features of *** normalization processing,energies are iterated using greedy algorithm to accelerate convergence *** experimental results encompassed examples in images and demonstrated the capabilities and efficiencies of the improvement.

关键词： remote sensing images coastline extraction active contour model greedy algorithm

维普期刊数据库

OPTIMIZATION OF MULTIPLE-CHANNEL COOPERATIVE SPECTRUM SENSING WITH DATA FUSION RULE IN COGNITIVE RADIO NETWORKS

在线全文

学校读者我要写书评

暂无评论

Journal of Electronics(China) 2012年第6期29卷 515-522页

作者： Yu Huogen Tang Wanbin Li Shaoqian National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of China

This paper focuses on multi-channel Cooperative Spectrum Sensing (CSS) where Secondary Users (SUs) are assigned to cooperatively sense multiple channels simultaneously. A multi-channel CSS optimization problem of joint spectrum sensing and SU assignment based on data fusion rule is formulated, which maximizes the total throughput of the Cognitive Radio Network (CRN) subject to the constraints of probabilities of detection and false alarm. To address the optimization problem, a Branch and Bound (BnB) algorithm and a greedy algorithm are proposed to obtain the optimal solutions. Simulation results are presented to demonstrate the effectiveness of our proposed algorithms and show that the throughput improvement is achieved through the joint design. It is also shown that the greedy algorithm with a low complexity achieves the comparable performance to the exhaustive algorithm.

关键词： Cooperative Spectrum Sensing (CSS) Cognitive radio Branch and Bound (BnB) algorithm greedy algorithm

维普期刊数据库

Studies on Human Face Recognition Based on greedy Kernel Principal Component Analysis

在线全文

学校读者我要写书评

暂无评论

Studies on Human Face Recognition Based on Greedy Kernel Pri...

Properly Weighted Independence Systemsand Applications to Scheduling Problems

第24届中国控制与决策会议

作者： WANG Xiaozhe, WANG Jinping, LI Chenyang College of Information Science and Engineering, Northeastern University, Shenyang 110004, China

A human face recognition algorithm based on greedy kernel principal component analysis （GKPCA） is presented to meet the requirement of quick face recognition on line. In the algorithm, typical human face are decomposed by fast wavelet transform（FWT）, then the greedy algorithm is used to reduce training set and the features of the low frequency sub-images are extracted by kernel principal component analysis（KPCA）. Consequently, the features extracted are recognized by support vector machine （SVM）. Simulations of the algorithm proposed on the basis of ORL （Olivetti Research Lab） face database and NORL face databases show that the algorithm is capable of reducing training time with high recognition rate.

关键词： greedy algorithm Kernel Principal Component Analysis (KPCA) Fast Wavelet Transform (FWT) Support Vector Machine (SVM) Face Recognition

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

运筹学学报 1997年第2期1卷 41-47页

作者： YIXUN LIN JUNQIANG DENG(Department of Mathematics, Zhengzhou University, Zhengzhou, Henan 450052) 郑州大学数学系河南郑州

The theory of independence systems is powerful in combinatorial optimization. Itis well-known that the greedy algorithm solves the maximum weight independent setproblem for a matroid with any weight function. However, this may not be true fora general independence system. In this paper we propose a condition on the weightfunctions (called the proper weight functions) that guarantees the greedy solvability foran independence system. Applying this general result to scheduling problems, some newinsights, as well as new algorithms, are obtained.

关键词： Combinatorial optimization Independence system greedy algorithm Scheduling

A Hybrid Genetic algorithm for Vehicle Routing Problem with Complex Constraints

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Journal of Plant Engineering and Management 2006年第2期11卷 88-96页

作者： CHEN Yan LU Jun LI Zeng-zhi School of Electronics and Information Engineering Xi＇an Jiaotong University Xi＇an 710049 P. R. China

Most research on the Vehicle Routing Problem （VRP） is focused on standard conditions, which is not suitable for specific cases. A Hybrid Genetic algorithm is proposed to solve a Vehicle Routing Problem （VRP） with complex side constraints. A novel coding method is designed especially for side constraints. A greedy algorithm combined with a random algorithm is introduced to enable the diversity of the initial population, as well as a local optimization algorithm employed to improve the searching efficiency. In order to evaluate the performance, this mechanism has been implemented in an oil distribution center, the experimental and executing results show that the near global optimal solution can be easily and quickly obtained by this method, and the solution is definitely satisfactory in the VRP application.

关键词： genetic algorithm vehicle routing problem greedy algorithm complex constraints

维普期刊数据库

Hybrid Relaying Protocol for Joint Power and Subcarrier Allocation for OFDM Based Cognitive Radio Networks

在线全文

学校读者我要写书评

暂无评论

Circuits and Systems 2016年第10期7卷 3150-3161页

作者： Muthusamy Bhuvaneswari Shama Srinivasa Rao Madane Department of Electronics and Communication Engineering Indra Ganesan College of Engineering Trichy India Adhi Parasakthi College of Engineering Kalavai India

This paper aims to avoid the interference imposed by the secondary user on a primary user in Cognitive Radio Network (CRN). In CRN, the interference from secondary user enforced on primary user mainly depends on spectral interval between primary and secondary systems. Moreover, it also depends on the power allocated to the secondary user. In order to avoid interference imposed by secondary user on primary user, a Hybrid Relaying Protocol for Joint Power and Subcarrier Allocation for Orthogonal Frequency Division Multiplexing (OFDM) based Cognitive Radio Networks is proposed. In hybrid relaying protocol, a secondary user uses amplify and forward (AF) protocol and decode and forward (DF) protocol based on the requirement to maximize network throughput. A greedy algorithm is proposed for the selection of relay to get the optimal solution. Moreover, an efficient hybrid power and subcarrier algorithm is used by considering interference constraint imposed by cognitive network to the primary user.

关键词： Orthogonal Frequency Division Multiplexing Interference Relay Power Amplify and Forward Decode and Forward greedy algorithm

A novel approach for radio resource management in multi-dimensional heterogeneous 5G networks

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Communications and Information Networks 2016年第2期1卷 77-83页

作者： HUI Leifang MA Wei ZHAI Shenghua Academy of Space Information System Xi'an 710100China

A GRA-BKP(Grey Relational Analysis-Bounded Knapsack Problem)scheme was proposed for the radio resource management of the 5G *** consists of two steps,access selection and admission *** former step was executed via GRA,whereas the latter problem was formulated as a bounded knapsack ***,an optimal solution of the BKP was given for access selection a greedy algorithm,GRA-greedy,was proposed for admission *** simulation results show that the GRA-BKP scheme can effectively increase system profit and decrease the drop-ping probability compared with the existing *** addition,GRA-greedy achieves comparable perform-ance with the optimal solution GRA-DP,but its computational complexity is much lower than that of the latter.

关键词： access selection admission control knapsack problem greedy algorithm

Optimal Search for Hidden Targets by Unmanned Aerial Vehicles under Imperfect Inspections

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

American Journal of Operations Research 2016年第2期6卷 153-166页

作者： Boris Kriheli Eugene Levner Alexander Spivak Department of Logistics Ashkelon Academic College Ashkelon Israel Department of Computer Science Holon Institute of Technology Holon Israel

Assume that a target is hidden or lost in one of several possible locations and is to be found by the unmanned aerial vehicle (UAV). A target can be either a hostile object or missing personnel in remote areas. Prior probabilities of target locations are known. Inspection operations done by the UAVs are imperfect, namely, probabilities of overlooking the hidden target and probabilities of false alarms exist for any possible location. The UAV has to sequentially inspect the locations so that to find the target with the minimum loss or damage incurred by the target before it is detected subject to a required level of confidence of target identification. A fast (polynomial-time) priority-based algorithm for finding an optimal search strategy is developed.

关键词： Search and Detection Discrete Search Imperfect Inspection greedy algorithm