A flexible and extendible control mechanism for invoking services is required for taking full advantage of the potential B--ISDN services. In this paper, a flexible specification of signaling protocol based on an obje...A flexible and extendible control mechanism for invoking services is required for taking full advantage of the potential B--ISDN services. In this paper, a flexible specification of signaling protocol based on an object-oriented call mode is proposed. The article’focuses on the protocol’s message syntax, message flow model, and applicability for defining multimedia and multiparty services.’展开更多
Emission projection and marginal abatement cost curves(MACs) are the central components of any assessment of future carbon market, such as CDM (clean development mechanism) potentials, carbon quota price etc. However,...Emission projection and marginal abatement cost curves(MACs) are the central components of any assessment of future carbon market, such as CDM (clean development mechanism) potentials, carbon quota price etc. However, they are products of very complex, dynamic systems driven by forces like population growth, economic development, resource endowments, technology progress and so on. The modeling approaches for emission projection and MACs evaluation were summarized, and some major models and their results were compared. Accordingly, reduction and cost requirements to achieve the Kyoto target were estimated. It is concluded that Annex I Parties' total reduction requirements range from 503—1304 MtC with USA participation and decrease significantly to 140—612 MtC after USA's withdrawal. Total costs vary from 21—77 BUSD with USA and from 5—36 BUSD without USA if only domestic reduction actions are taken. The costs would sharply reduce while considering the three flexible mechanisms defined in the Kyoto Protocol with domestic actions' share in the all mitigation strategies drops to only 0—16%.展开更多
Congestion management in an electricity market is introduced in this paper and a new method of allocating congestion cost to transactions is proposed. The proposed method is a two-step process, in which the total cong...Congestion management in an electricity market is introduced in this paper and a new method of allocating congestion cost to transactions is proposed. The proposed method is a two-step process, in which the total congestion cost is firstly allocated to congested facilities and then to each transaction involved. The cost of relieving a congested facility allocated to each transaction is proportional to the power flow change on the congested facility caused by the transaction. The more the power flow change is on the congested facility caused by the transaction, the deeper the degree of involvement by the transaction. Therefore, cutting down the magnitudes of such transactions contributes to relieving congestion. Test results on a 5-bus system indicate that the proposed method can reflect reasonably the degree of involvement by each transaction in the congestion and provide correct price signals contributing to relieving congestion.展开更多
OAM (Operations, Administration and Maintenance) system is a very impo rtant component of 3G cellular network. In order to acquire overall managemen t, fast response and steady operation, an SCTP (Stream Control Trans...OAM (Operations, Administration and Maintenance) system is a very impo rtant component of 3G cellular network. In order to acquire overall managemen t, fast response and steady operation, an SCTP (Stream Control Transmission Prot ocol) based OAM, i.e., SOAM system was proposed. SOAM implements new characters of SCTP such as multi-stream, enforced SACK and heartbeat mechanism on its tran sport layer. These characters help SOAM decrease the message transmission delay and accelerate the link failure detection. Besides, a new component named SOAM agent was introduced to improve the operation efficiency of SOAM. The experim ental results prove the proposed SOAM system achieves better performance on sign aling transmission compared with conventional TCP based OAM system.展开更多
Cognitive radio technology makes efficient use of the valuable radio frequency spectrum in a non-interfering manner to solve the problem of spectrum scarcity. This paper aims to design a scheme for the concurrent use ...Cognitive radio technology makes efficient use of the valuable radio frequency spectrum in a non-interfering manner to solve the problem of spectrum scarcity. This paper aims to design a scheme for the concurrent use of licensed frequencies by Underlay Cognitive Users (UCUs). We develop a new receiver-initiated Medium Access Control (MAC) protocol to facilitate the selections of alternative reliable carrier frequencies. A circuit is designed to establish reliable carrier selections based on the Received Signal Strength Indicator (RSSI) at the receiving end. Based on both packet-level simulations and various performance parameters, a comparison is carried out among conventional techniques, including the Multiple Access with Collision Avoidance (MACA) and MACA by invitation(MACA-BI) techniques, and our scheme. The simulated results demonstrate that when conventional techniques are used, the system overhead time increases from 0.5 s on the first attempt to 16.5 s on the sixth attempt. In the proposed scheme under the same failure condition, overhead time varies from 0.5 s to 2 s. This improvement is due to the complete elimination of the exponential waiting time that occurs during failed transmissions. An average efficiency of 60% is achieved with our scheme while only 43% and 34% average efficiencies are achieved with the MACA and MACA-BI techniques, respectively. The throughput performance of our scheme on the fourth attempt is 7 Mbps, whereas for the MACA and MACA-BI protocols, it is 1.9 Mbps and 2.2 Mbps respectively.展开更多
This paper focuses on addressing the problems of finite-time boundedness and guaranteed cost control in switched systems under asynchronous switching.To reduce redundant information transmission and alleviate data con...This paper focuses on addressing the problems of finite-time boundedness and guaranteed cost control in switched systems under asynchronous switching.To reduce redundant information transmission and alleviate data congestion of sensor nodes,two schemes are proposed:the event-triggered scheme(ETS)and the round-robin protocol(RRP).These schemes are designed to ensure that the system exhibits good dynamic characteristics while reducing communication resources.In the field of finite-time control,a switching signal is designed using the admissible edge-dependent average dwell time(AED-ADT)method.This method involves a slow AED-ADT switching and a fast AED-ADT switching,which are respectively suitable for finite-time stable and finite-time unstable situations of the controlled system within the asynchronous switching interval.By constructing a double-mode dependent Lyapunov function,the finite-time bounded criterion and the controller gain of the switched systems are obtained.Finally,the validity of the proposed results is showcased by implementing a buck-boost voltage circuit model.展开更多
网际互连协议(Internet Protocol,IP)化网络作为一种新兴的传输技术,正在改变传统的电视制作和播出模式。基于此,概述了IP化技术的相关概念,分析了IP化技术的数字编码和分组传输机制,阐述了IP化技术在推动电视制播融合方面的作用,提出...网际互连协议(Internet Protocol,IP)化网络作为一种新兴的传输技术,正在改变传统的电视制作和播出模式。基于此,概述了IP化技术的相关概念,分析了IP化技术的数字编码和分组传输机制,阐述了IP化技术在推动电视制播融合方面的作用,提出了电视制播IP化网络的分层架构,解析了IP化核心网和接入网的组成,以及软件定义网络(Software Defined Network,SDN)在IP化网络中的控制作用。展开更多
文摘A flexible and extendible control mechanism for invoking services is required for taking full advantage of the potential B--ISDN services. In this paper, a flexible specification of signaling protocol based on an object-oriented call mode is proposed. The article’focuses on the protocol’s message syntax, message flow model, and applicability for defining multimedia and multiparty services.’
文摘Emission projection and marginal abatement cost curves(MACs) are the central components of any assessment of future carbon market, such as CDM (clean development mechanism) potentials, carbon quota price etc. However, they are products of very complex, dynamic systems driven by forces like population growth, economic development, resource endowments, technology progress and so on. The modeling approaches for emission projection and MACs evaluation were summarized, and some major models and their results were compared. Accordingly, reduction and cost requirements to achieve the Kyoto target were estimated. It is concluded that Annex I Parties' total reduction requirements range from 503—1304 MtC with USA participation and decrease significantly to 140—612 MtC after USA's withdrawal. Total costs vary from 21—77 BUSD with USA and from 5—36 BUSD without USA if only domestic reduction actions are taken. The costs would sharply reduce while considering the three flexible mechanisms defined in the Kyoto Protocol with domestic actions' share in the all mitigation strategies drops to only 0—16%.
文摘Congestion management in an electricity market is introduced in this paper and a new method of allocating congestion cost to transactions is proposed. The proposed method is a two-step process, in which the total congestion cost is firstly allocated to congested facilities and then to each transaction involved. The cost of relieving a congested facility allocated to each transaction is proportional to the power flow change on the congested facility caused by the transaction. The more the power flow change is on the congested facility caused by the transaction, the deeper the degree of involvement by the transaction. Therefore, cutting down the magnitudes of such transactions contributes to relieving congestion. Test results on a 5-bus system indicate that the proposed method can reflect reasonably the degree of involvement by each transaction in the congestion and provide correct price signals contributing to relieving congestion.
基金High-Tech Research and DevelopmentProgram of China (No. 2003AA123310)
文摘OAM (Operations, Administration and Maintenance) system is a very impo rtant component of 3G cellular network. In order to acquire overall managemen t, fast response and steady operation, an SCTP (Stream Control Transmission Prot ocol) based OAM, i.e., SOAM system was proposed. SOAM implements new characters of SCTP such as multi-stream, enforced SACK and heartbeat mechanism on its tran sport layer. These characters help SOAM decrease the message transmission delay and accelerate the link failure detection. Besides, a new component named SOAM agent was introduced to improve the operation efficiency of SOAM. The experim ental results prove the proposed SOAM system achieves better performance on sign aling transmission compared with conventional TCP based OAM system.
文摘Cognitive radio technology makes efficient use of the valuable radio frequency spectrum in a non-interfering manner to solve the problem of spectrum scarcity. This paper aims to design a scheme for the concurrent use of licensed frequencies by Underlay Cognitive Users (UCUs). We develop a new receiver-initiated Medium Access Control (MAC) protocol to facilitate the selections of alternative reliable carrier frequencies. A circuit is designed to establish reliable carrier selections based on the Received Signal Strength Indicator (RSSI) at the receiving end. Based on both packet-level simulations and various performance parameters, a comparison is carried out among conventional techniques, including the Multiple Access with Collision Avoidance (MACA) and MACA by invitation(MACA-BI) techniques, and our scheme. The simulated results demonstrate that when conventional techniques are used, the system overhead time increases from 0.5 s on the first attempt to 16.5 s on the sixth attempt. In the proposed scheme under the same failure condition, overhead time varies from 0.5 s to 2 s. This improvement is due to the complete elimination of the exponential waiting time that occurs during failed transmissions. An average efficiency of 60% is achieved with our scheme while only 43% and 34% average efficiencies are achieved with the MACA and MACA-BI techniques, respectively. The throughput performance of our scheme on the fourth attempt is 7 Mbps, whereas for the MACA and MACA-BI protocols, it is 1.9 Mbps and 2.2 Mbps respectively.
基金Project supported by the Natural Science Foundation of Henan Province,China(No.242300421175)the National Natural Science Foundation of China(No.62003311)+2 种基金the China Postdoctoral Science Foundation(No.2023M743191)the Key Scientific Research Projects of Higher Education Institutions in Henan Province,China(No.24A120013)the Natural Science Foundation of Shandong Province,China(No.ZR2023MF049)。
文摘This paper focuses on addressing the problems of finite-time boundedness and guaranteed cost control in switched systems under asynchronous switching.To reduce redundant information transmission and alleviate data congestion of sensor nodes,two schemes are proposed:the event-triggered scheme(ETS)and the round-robin protocol(RRP).These schemes are designed to ensure that the system exhibits good dynamic characteristics while reducing communication resources.In the field of finite-time control,a switching signal is designed using the admissible edge-dependent average dwell time(AED-ADT)method.This method involves a slow AED-ADT switching and a fast AED-ADT switching,which are respectively suitable for finite-time stable and finite-time unstable situations of the controlled system within the asynchronous switching interval.By constructing a double-mode dependent Lyapunov function,the finite-time bounded criterion and the controller gain of the switched systems are obtained.Finally,the validity of the proposed results is showcased by implementing a buck-boost voltage circuit model.
文摘网际互连协议(Internet Protocol,IP)化网络作为一种新兴的传输技术,正在改变传统的电视制作和播出模式。基于此,概述了IP化技术的相关概念,分析了IP化技术的数字编码和分组传输机制,阐述了IP化技术在推动电视制播融合方面的作用,提出了电视制播IP化网络的分层架构,解析了IP化核心网和接入网的组成,以及软件定义网络(Software Defined Network,SDN)在IP化网络中的控制作用。