The controller is indispensable in software-defined networking(SDN).With several features,controllers monitor the network and respond promptly to dynamic changes.Their performance affects the quality-of-service(QoS)in...The controller is indispensable in software-defined networking(SDN).With several features,controllers monitor the network and respond promptly to dynamic changes.Their performance affects the quality-of-service(QoS)in SDN.Every controller supports a set of features.However,the support of the features may be more prominent in one controller.Moreover,a single controller leads to performance,single-point-of-failure(SPOF),and scalability problems.To overcome this,a controller with an optimum feature set must be available for SDN.Furthermore,a cluster of optimum feature set controllers will overcome an SPOF and improve the QoS in SDN.Herein,leveraging an analytical network process(ANP),we rank SDN controllers regarding their supporting features and create a hierarchical control plane based cluster(HCPC)of the highly ranked controller computed using the ANP,evaluating their performance for the OS3E topology.The results demonstrated in Mininet reveal that a HCPC environment with an optimum controller achieves an improved QoS.Moreover,the experimental results validated in Mininet show that our proposed approach surpasses the existing distributed controller clustering(DCC)schemes in terms of several performance metrics i.e.,delay,jitter,throughput,load balancing,scalability and CPU(central processing unit)utilization.展开更多
With the development of fracture mechanics,the fracture plane control blasting with notched borcholes hascome into being.This technique is used to create a satisfactory presplit along the contour of an excavation inro...With the development of fracture mechanics,the fracture plane control blasting with notched borcholes hascome into being.This technique is used to create a satisfactory presplit along the contour of an excavation inrock.However,the amount of explosive loaded in each hol usually is determined by trial and error.Because ofthis,two approaches estimating the amount of explosive for the blasting technique are suggested.展开更多
The Pre-Stack Depth Migration （PSDM） method based on wavefield continuation is the most reliable method for imaging complex structure in the subsurface, although there are large computational costs and poorly adapti...The Pre-Stack Depth Migration （PSDM） method based on wavefield continuation is the most reliable method for imaging complex structure in the subsurface, although there are large computational costs and poorly adaptive geometry. Plane wave shot migration is another method to perform exact wave equation prestack imaging with high computational efficiency and without the migration aperture problem. Moreover, wavefield energy can be compensated at the target zone by controlled illumination. In this paper, plane wave shot PSDM was implemented by the control of the plane down-going wavefield and selection of number and range of the raypaths in order to optimize the imaging effect. In addition, controlled illumination techniques are applied to enhance the imaging precision of interesting areas at different depths. Numerical calculation indicates that plane wave shot imaging is a rapid and efficient method with less computational cost and easy parallel computation compared to the single-square-root operator imaging for common shot gathers and double- square-root operator imaging for common midpoint gathers.展开更多
For the next generation optical switching networks, the intelligent control plane is a key enabling technique. In this paper, we review our recent research activities related to Generalized Multi-Protocol Label Switch...For the next generation optical switching networks, the intelligent control plane is a key enabling technique. In this paper, we review our recent research activities related to Generalized Multi-Protocol Label Switching (GMPLS) and Open Flow-based control planes for both Wave length Switched Optical Networks (WSON) and Elastic Optical Networks (EON).展开更多
Based on the deep analysis of the mathematical model of an autonomous underwater vehicle( AUV),comprehensive considerations are given to the coupling effect of AUV's longitudinal velocity on the other degrees of f...Based on the deep analysis of the mathematical model of an autonomous underwater vehicle( AUV),comprehensive considerations are given to the coupling effect of AUV's longitudinal velocity on the other degrees of freedom. In the meantime,discussions are made on the influence of residual buoyancy and restoring moment.A novel S-plane controller established on sliding mode control( SMC) is hereby proposed in this study. The strengths of traditional S-plane controller including simple structure and easily adjustable parameters are maintained in the improved design while the weakness of unsatisfactory control effect at the time of high-speed operation is also overcome. Lyapunov function is introduced to make the stability analysis of the controller before it is successfully applied to the basic motion control of AUV-X. Then the comparative experiment test is carried out between the traditional S-plane controller and the novel S-plane controller. The effectiveness and feasibility of the novel S-plane controller established on sliding mode control in the AUV basic motion control is verified by the comparative analysis of experiment results.展开更多
Blasting operation dissipates much of the blasting energy in crushing the rock at the borehole and the resulting cracks are randomly oriented. There is very little control of the fracture plane. In order to control th...Blasting operation dissipates much of the blasting energy in crushing the rock at the borehole and the resulting cracks are randomly oriented. There is very little control of the fracture plane. In order to control the fracture plane, many methods have been applied. This paper discusses a new blasting method in which a high degree of fracture control can be achieved while minimizing the ground shock.展开更多
G2MPLS is a Network Control Plane(NCP) architecture that implements the concept of Grid Network Services(GNS) required for implementing photonic Grids.It provides part of the functionalities related to the selection,c...G2MPLS is a Network Control Plane(NCP) architecture that implements the concept of Grid Network Services(GNS) required for implementing photonic Grids.It provides part of the functionalities related to the selection,co-allocation and maintenance of both Grid and network resources through a set of seamless procedures at the user-to-network and inter-domain boundaries.G2MPLS' main features and procedures are presented in this document,as well as the considerations to deploy it and facilitate its dissemination.展开更多
The information centric network(ICN)has been widely discussed in current researches.The ICN interoperation with a traditional IP network and caching methods are one of the research topics of interest.For economic reas...The information centric network(ICN)has been widely discussed in current researches.The ICN interoperation with a traditional IP network and caching methods are one of the research topics of interest.For economic reasons,the capability of applying the ICN to internet service providers(ISPs)with various traditional IP protocols already implemented,especially IGP,MPLS,VRF,and TE,does not require any change on the IP network infrastructure.The biggest concern of ISPs is related to their customers’contents delivery speed.In this paper,we consider ICN caching locations in ISP by using the concept of locator/ID separation protocol(LISP)for interoperation between a traditional IP address and name-based ICN.To be more specific,we propose a new procedure to determine caching locations in the ICN by using the cuckoo search algorithm(CSA)for finding the best caching locations of information chunks.Moreover,we create the smart control plane(SCP)scheme which is an intelligent controlling,managing,and mapping system.Its function is similar to the software defined network concept.We show how the proposed SCP system works in both synthetic small network and real-world big network.Finally,we show and evaluate the performance of our algorithm comparison with the simple search method using the shortest path first algorithm.展开更多
In a translucent network scenario, development of an optical control plane (OCP) that is aware of the location and number of available regenerators and all-optical wavelength converters (AOWCs) is of paramount importa...In a translucent network scenario, development of an optical control plane (OCP) that is aware of the location and number of available regenerators and all-optical wavelength converters (AOWCs) is of paramount importance. However, current generalized multiprotocol label switching (GMPLS) protocol suite does not consider the distribution of regenerator and AOWC availability information to all the network nodes. In this paper, we propose a novel optical control plane (OCP) architecture that 1) disseminates information about network components (i.e. regenerators and AOWCs) to all the network nodes, and 2) evaluates candidate routes which use fewest amounts of network components. Performance of the proposed OCP is compared with a recently proposed hybrid OCP approach in terms of blocking performance, number of deployed components and lightpath establishment setup times. The obtained simulation results show that the proposed OCP approach demonstrates low connection blocking and establishes lightpaths by 1) minimizing the overall network cost owing to the deployment of minimum total number of network components, and 2) demonstrating acceptable lightpath establishment setup times at all traffic loads. Further, the proposed OCP methodology is compatible and suitable for controlling the operations of a novel electro-optical hybrid translucent node which is a latency efficient technology capable of delivering a cost effective implementation suitable for large scale deployment.展开更多
The heterogeneous network with the separation of the control plane and user plane(C/U) is an evolutionary approach to the fifth generation(5 G) to achieve high system coverage and capacity. To minimize signaling load ...The heterogeneous network with the separation of the control plane and user plane(C/U) is an evolutionary approach to the fifth generation(5 G) to achieve high system coverage and capacity. To minimize signaling load of the core network when there is a macro base station(BS) failure in the control plane, a scheme of transferring the control of small cells under the coverage of the failure macro BS to the neighbor macro BSs is proposed. The average handover rates between small cells related to user mobilities, the extended coverage of the neighboring macro BSs under the constraint of transmitting power and the load balance index of the system are analyzed, based on which the formula of maximizing the handovers processed by macro BSs is constructed and further solved by the convex optimization methods. Simulation results indicate that the proposed scheme can effectively increase the total handovers processed by the macro BSs and thus reduce the signaling load of the core network.展开更多
基金supported by the MSIT(Ministry of Science and ICT),Korea,under the ITRC(Information Technology Research Center)support program(IITP-2020-2018-0-01431)supervised by the IITP(Institute for Information&Communications Technology Planning&Evaluation).
文摘The controller is indispensable in software-defined networking(SDN).With several features,controllers monitor the network and respond promptly to dynamic changes.Their performance affects the quality-of-service(QoS)in SDN.Every controller supports a set of features.However,the support of the features may be more prominent in one controller.Moreover,a single controller leads to performance,single-point-of-failure(SPOF),and scalability problems.To overcome this,a controller with an optimum feature set must be available for SDN.Furthermore,a cluster of optimum feature set controllers will overcome an SPOF and improve the QoS in SDN.Herein,leveraging an analytical network process(ANP),we rank SDN controllers regarding their supporting features and create a hierarchical control plane based cluster(HCPC)of the highly ranked controller computed using the ANP,evaluating their performance for the OS3E topology.The results demonstrated in Mininet reveal that a HCPC environment with an optimum controller achieves an improved QoS.Moreover,the experimental results validated in Mininet show that our proposed approach surpasses the existing distributed controller clustering(DCC)schemes in terms of several performance metrics i.e.,delay,jitter,throughput,load balancing,scalability and CPU(central processing unit)utilization.
文摘With the development of fracture mechanics,the fracture plane control blasting with notched borcholes hascome into being.This technique is used to create a satisfactory presplit along the contour of an excavation inrock.However,the amount of explosive loaded in each hol usually is determined by trial and error.Because ofthis,two approaches estimating the amount of explosive for the blasting technique are suggested.
基金This project is sporspored by Fund item:the National Development and Innovation Committee Program (2005) 2372the National High-tech R&D Program (863 Program) 2006AA06Z241 of ChinaYouth Innovation Fund of CNPC (Program:Prestack Imaging Integral Study for Complex near Surface)
文摘The Pre-Stack Depth Migration （PSDM） method based on wavefield continuation is the most reliable method for imaging complex structure in the subsurface, although there are large computational costs and poorly adaptive geometry. Plane wave shot migration is another method to perform exact wave equation prestack imaging with high computational efficiency and without the migration aperture problem. Moreover, wavefield energy can be compensated at the target zone by controlled illumination. In this paper, plane wave shot PSDM was implemented by the control of the plane down-going wavefield and selection of number and range of the raypaths in order to optimize the imaging effect. In addition, controlled illumination techniques are applied to enhance the imaging precision of interesting areas at different depths. Numerical calculation indicates that plane wave shot imaging is a rapid and efficient method with less computational cost and easy parallel computation compared to the single-square-root operator imaging for common shot gathers and double- square-root operator imaging for common midpoint gathers.
文摘For the next generation optical switching networks, the intelligent control plane is a key enabling technique. In this paper, we review our recent research activities related to Generalized Multi-Protocol Label Switching (GMPLS) and Open Flow-based control planes for both Wave length Switched Optical Networks (WSON) and Elastic Optical Networks (EON).
基金Sponsored by the National High Technology Research and Development Program of China(Grant Nos.2011AA09A106,2008AA092301)the National Nature Science Foundation of China(Grant Nos.50909025,51009040 and 51179035)
文摘Based on the deep analysis of the mathematical model of an autonomous underwater vehicle( AUV),comprehensive considerations are given to the coupling effect of AUV's longitudinal velocity on the other degrees of freedom. In the meantime,discussions are made on the influence of residual buoyancy and restoring moment.A novel S-plane controller established on sliding mode control( SMC) is hereby proposed in this study. The strengths of traditional S-plane controller including simple structure and easily adjustable parameters are maintained in the improved design while the weakness of unsatisfactory control effect at the time of high-speed operation is also overcome. Lyapunov function is introduced to make the stability analysis of the controller before it is successfully applied to the basic motion control of AUV-X. Then the comparative experiment test is carried out between the traditional S-plane controller and the novel S-plane controller. The effectiveness and feasibility of the novel S-plane controller established on sliding mode control in the AUV basic motion control is verified by the comparative analysis of experiment results.
文摘Blasting operation dissipates much of the blasting energy in crushing the rock at the borehole and the resulting cracks are randomly oriented. There is very little control of the fracture plane. In order to control the fracture plane, many methods have been applied. This paper discusses a new blasting method in which a high degree of fracture control can be achieved while minimizing the ground shock.
文摘G2MPLS is a Network Control Plane(NCP) architecture that implements the concept of Grid Network Services(GNS) required for implementing photonic Grids.It provides part of the functionalities related to the selection,co-allocation and maintenance of both Grid and network resources through a set of seamless procedures at the user-to-network and inter-domain boundaries.G2MPLS' main features and procedures are presented in this document,as well as the considerations to deploy it and facilitate its dissemination.
文摘The information centric network(ICN)has been widely discussed in current researches.The ICN interoperation with a traditional IP network and caching methods are one of the research topics of interest.For economic reasons,the capability of applying the ICN to internet service providers(ISPs)with various traditional IP protocols already implemented,especially IGP,MPLS,VRF,and TE,does not require any change on the IP network infrastructure.The biggest concern of ISPs is related to their customers’contents delivery speed.In this paper,we consider ICN caching locations in ISP by using the concept of locator/ID separation protocol(LISP)for interoperation between a traditional IP address and name-based ICN.To be more specific,we propose a new procedure to determine caching locations in the ICN by using the cuckoo search algorithm(CSA)for finding the best caching locations of information chunks.Moreover,we create the smart control plane(SCP)scheme which is an intelligent controlling,managing,and mapping system.Its function is similar to the software defined network concept.We show how the proposed SCP system works in both synthetic small network and real-world big network.Finally,we show and evaluate the performance of our algorithm comparison with the simple search method using the shortest path first algorithm.
文摘In a translucent network scenario, development of an optical control plane (OCP) that is aware of the location and number of available regenerators and all-optical wavelength converters (AOWCs) is of paramount importance. However, current generalized multiprotocol label switching (GMPLS) protocol suite does not consider the distribution of regenerator and AOWC availability information to all the network nodes. In this paper, we propose a novel optical control plane (OCP) architecture that 1) disseminates information about network components (i.e. regenerators and AOWCs) to all the network nodes, and 2) evaluates candidate routes which use fewest amounts of network components. Performance of the proposed OCP is compared with a recently proposed hybrid OCP approach in terms of blocking performance, number of deployed components and lightpath establishment setup times. The obtained simulation results show that the proposed OCP approach demonstrates low connection blocking and establishes lightpaths by 1) minimizing the overall network cost owing to the deployment of minimum total number of network components, and 2) demonstrating acceptable lightpath establishment setup times at all traffic loads. Further, the proposed OCP methodology is compatible and suitable for controlling the operations of a novel electro-optical hybrid translucent node which is a latency efficient technology capable of delivering a cost effective implementation suitable for large scale deployment.
基金Supported by Basic Research Program of BJUT(No.040000546317525)National Natural Science Foundation of China(No.61571021)+1 种基金Foundation of Beijing Municipal Commission of Education(No.KM201610005004,KM201510005006)Beijing Postdoctoral Research Foundation(No.2018ZZ029)
文摘The heterogeneous network with the separation of the control plane and user plane(C/U) is an evolutionary approach to the fifth generation(5 G) to achieve high system coverage and capacity. To minimize signaling load of the core network when there is a macro base station(BS) failure in the control plane, a scheme of transferring the control of small cells under the coverage of the failure macro BS to the neighbor macro BSs is proposed. The average handover rates between small cells related to user mobilities, the extended coverage of the neighboring macro BSs under the constraint of transmitting power and the load balance index of the system are analyzed, based on which the formula of maximizing the handovers processed by macro BSs is constructed and further solved by the convex optimization methods. Simulation results indicate that the proposed scheme can effectively increase the total handovers processed by the macro BSs and thus reduce the signaling load of the core network.
