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Efficient Virtual Network Embedding Algorithm Based on Restrictive Selection and Optimization Theory Approach 被引量:2
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作者 Haotong Cao Zhicheng Qu +1 位作者 Yishi Xue Longxiang Yang 《China Communications》 SCIE CSCD 2017年第10期39-60,共22页
Network virtualization(NV) is widely considered as a key component of the future network and promises to allow multiple virtual networks(VNs) with different protocols to coexist on a shared substrate network(SN). One ... Network virtualization(NV) is widely considered as a key component of the future network and promises to allow multiple virtual networks(VNs) with different protocols to coexist on a shared substrate network(SN). One main challenge in NV is virtual network embedding(VNE). VNE is a NPhard problem. Previous VNE algorithms in the literature are mostly heuristic, while the remaining algorithms are exact. Heuristic algorithms aim to find a feasible embedding of each VN, not optimal or sub-optimal, in polynomial time. Though presenting the optimal or sub-optimal embedding per VN, exact algorithms are too time-consuming in smallscaled networks, not to mention moderately sized networks. To make a trade-off between the heuristic and the exact, this paper presents an effective algorithm, labeled as VNE-RSOT(Restrictive Selection and Optimization Theory), to solve the VNE problem. The VNERSOT can embed virtual nodes and links per VN simultaneously. The restrictive selection contributes to selecting candidate substrate nodes and paths and largely cuts down on the number of integer variables, used in the following optimization theory approach. The VNE-RSOT fights to minimize substrate resource consumption and accommodates more VNs. To highlight the efficiency of VNERSOT, a simulation against typical and stateof-art heuristic algorithms and a pure exact algorithm is made. Numerical results reveal that virtual network request(VNR) acceptance ratio of VNE-RSOT is, at least, 10% higher than the best-behaved heuristic. Other metrics, such as the execution time, are also plotted to emphasize and highlight the efficiency of VNE-RSOT. 展开更多
关键词 network virtualization virtual network embedding NP-hard heuristic exact restrictive selection optimization theory
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Tool selection and collision-free in 5-axis numerical control machining of free-form surfaces
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作者 杨长祺 QIN +1 位作者 Datong 《Journal of Chongqing University》 CAS 2002年第2期20-23,共4页
The methodology of 5-axis cutter selection to avert collision for free-form surface machining by flat-end cutters is presented. The combination of different cutters is adopt aiming at short machining time and high pre... The methodology of 5-axis cutter selection to avert collision for free-form surface machining by flat-end cutters is presented. The combination of different cutters is adopt aiming at short machining time and high precision. The optimal small cutter is determined based on the geometric information of the points where a cutter most probably collide with the machined surface. Several larger cutters are selected to machine the surface in order to find the interference-free area. The difference of machining time for this area between the optimal small cutter and the large cutters is calculated. The functional relationship between the machining time and the radius of a cutter is established, by which the optimal number of cutters is obtained. The combination of cutters, which possesses the minimum overall machining time, is selected as the optimal cutter sizes. A case study has demonstrated the validity of the proposed methodology and algorithms. 展开更多
关键词 optimal tool selection collision-free tool path generation free-form surfaces flat-end cutter
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Spectral Match Optimization Based on Grey Relational Analysis
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作者 贾其 吕绪良 《Defence Technology(防务技术)》 CAS 2012年第1期21-25,共5页
A spectral match optimization based on grey incidence matrix was put forward to evaluate camouflage painting design.A synthetic degree of incidence (SDI) was defined to comprehensively reflect the spectrum similarity ... A spectral match optimization based on grey incidence matrix was put forward to evaluate camouflage painting design.A synthetic degree of incidence (SDI) was defined to comprehensively reflect the spectrum similarity based on theory of grey incidence analysis.A grey optimization model for camouflage painting sheme was constructed on the basis of SDI and grey incidence matrix.Its weight values were determined according to area percentages of all components in the camouflage scene,and a quantitative ordering for various schemes could be obtained according to the evaluation coefficients.Experiment results show that the method mentioned in this paper can provide a quantitative basis for the camouflage decision-making,and it can also be used in other camouflage scheme selection. 展开更多
关键词 OPTICS spectral match optimal selection synthetic degree of incidence APPLICATION
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Optimal Route Selection Method Based on Vague Sets
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作者 郭瑞 杜利敏 王淳 《Chinese Quarterly Journal of Mathematics》 2015年第1期130-136,共7页
Optimal route selection is an important function of vehicle trac flow guidance system. Its core is to determine the index weight for measuring the route merits and to determine the evaluation method for selecting rout... Optimal route selection is an important function of vehicle trac flow guidance system. Its core is to determine the index weight for measuring the route merits and to determine the evaluation method for selecting route. In this paper, subjective weighting method which relies on driver preference is used to determine the weight and the paper proposes the multi-criteria weighted decision method based on vague sets for selecting the optimal route. Examples show that, the usage of vague sets to describe route index value can provide more decision-making information for route selection. 展开更多
关键词 trafflc guidance optimal route selection vague sets multi-criteria fuzzy decision-making
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Towards complex scenes: A deep learning-based camouflaged people detection method for snapshot multispectral images 被引量:1
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作者 Shu Wang Dawei Zeng +3 位作者 Yixuan Xu Gonghan Yang Feng Huang Liqiong Chen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期269-281,共13页
Camouflaged people are extremely expert in actively concealing themselves by effectively utilizing cover and the surrounding environment. Despite advancements in optical detection capabilities through imaging systems,... Camouflaged people are extremely expert in actively concealing themselves by effectively utilizing cover and the surrounding environment. Despite advancements in optical detection capabilities through imaging systems, including spectral, polarization, and infrared technologies, there is still a lack of effective real-time method for accurately detecting small-size and high-efficient camouflaged people in complex real-world scenes. Here, this study proposes a snapshot multispectral image-based camouflaged detection model, multispectral YOLO(MS-YOLO), which utilizes the SPD-Conv and Sim AM modules to effectively represent targets and suppress background interference by exploiting the spatial-spectral target information. Besides, the study constructs the first real-shot multispectral camouflaged people dataset(MSCPD), which encompasses diverse scenes, target scales, and attitudes. To minimize information redundancy, MS-YOLO selects an optimal subset of 12 bands with strong feature representation and minimal inter-band correlation as input. Through experiments on the MSCPD, MS-YOLO achieves a mean Average Precision of 94.31% and real-time detection at 65 frames per second, which confirms the effectiveness and efficiency of our method in detecting camouflaged people in various typical desert and forest scenes. Our approach offers valuable support to improve the perception capabilities of unmanned aerial vehicles in detecting enemy forces and rescuing personnel in battlefield. 展开更多
关键词 Camouflaged people detection Snapshot multispectral imaging Optimal band selection MS-YOLO Complex remote sensing scenes
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A Novel Improved Artificial Bee Colony and Blockchain-Based Secure Clustering Routing Scheme for FANET 被引量:1
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作者 Liang Zhao Muhammad Bin Saif +3 位作者 Ammar Hawbani Geyong Min Su Peng Na Lin 《China Communications》 SCIE CSCD 2021年第7期103-116,共14页
Flying Ad hoc Network(FANET)has drawn significant consideration due to its rapid advancements and extensive use in civil applications.However,the characteristics of FANET including high mobility,limited resources,and ... Flying Ad hoc Network(FANET)has drawn significant consideration due to its rapid advancements and extensive use in civil applications.However,the characteristics of FANET including high mobility,limited resources,and distributed nature,have posed a new challenge to develop a secure and ef-ficient routing scheme for FANET.To overcome these challenges,this paper proposes a novel cluster based secure routing scheme,which aims to solve the routing and data security problem of FANET.In this scheme,the optimal cluster head selection is based on residual energy,online time,reputation,blockchain transactions,mobility,and connectivity by using Improved Artificial Bee Colony Optimization(IABC).The proposed IABC utilizes two different search equations for employee bee and onlooker bee to enhance convergence rate and exploitation abilities.Further,a lightweight blockchain consensus algorithm,AI-Proof of Witness Consensus Algorithm(AI-PoWCA)is proposed,which utilizes the optimal cluster head for mining.In AI-PoWCA,the concept of the witness for block verification is also involved to make the proposed scheme resource efficient and highly resilient against 51%attack.Simulation results demonstrate that the proposed scheme outperforms its counterparts and achieves up to 90%packet delivery ratio,lowest end-to-end delay,highest throughput,resilience against security attacks,and superior in block processing time. 展开更多
关键词 improved artificial bee colony optimization optimal cluster head selection secure routing blockchain lightweight consensus protocol
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F-18 fluorodeoxyglucose imaging to differentiate the response to cardiac conduction system pacing in patients with pacing induced cardiomyopathy
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作者 Yu ZHANG Xiao-Hong ZHOU +2 位作者 Yang YE Zhong-Ke HUANG Guo-Sheng FU 《Journal of Geriatric Cardiology》 2025年第3期411-414,共4页
Pacing-induced cardiomyopathy (PICM) resultsf rom the detrimental effect of frequent right ventricular pacing.^([1]) The diagnosis relies on a combination of pacing-associated ventricular dyschrony manifested with ECG... Pacing-induced cardiomyopathy (PICM) resultsf rom the detrimental effect of frequent right ventricular pacing.^([1]) The diagnosis relies on a combination of pacing-associated ventricular dyschrony manifested with ECG wide LBBB-pattern QRS duration and clinical assessment, imaging studies. Conduction system pacing (CSP), such as His bundle pacing (HBP)and left bundle branch pacing (LBBP), may help to prevent PICM,^([2]) but the criteria for optimal patient selection remain inadequately defined. 展开更多
关键词 conduction system pacing cardiac conduction system pacing clinical assessment f fluorodeoxyglucose imaging left bundle branch pacing pacing induced cardiomyopathy optimal patient selection imaging studies
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