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Efficacy and safety of mild-warm moxibustion in treating diarrhea-predominant irritable bowel syndrome(spleen deficiency and dampness excess syndrome):a study protocol for a randomized controlled trial
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作者 Yun-Yi Chen Jing Gu +4 位作者 Yu-Hui Wang Hua Huang Li-Ying Fang Qian Fan Li-Jiang Ji 《TMR Non-Drug Therapy》 2023年第2期1-11,共11页
1Background:Irritable bowel syndrome(IBS)is a disorder of bowel function,and diarrhea-predominant irritable bowel syndrome(IBS-D)is the most common.The current treatment for IBS-D is focused on improving patients’gas... 1Background:Irritable bowel syndrome(IBS)is a disorder of bowel function,and diarrhea-predominant irritable bowel syndrome(IBS-D)is the most common.The current treatment for IBS-D is focused on improving patients’gastrointestinal-related symptoms,but there are limitations such as unstable effects and adverse drug reactions.Acupuncture and moxibustion exerts advantages in treating IBS-D.They include several forms,of which moxibustion is one of the most commonly used.And moxibustion is a common way used in treating IBS-D,but there is a lack of relevant evidence-based medical research data.This protocol aims to compare the efficacy of moxibustion(mild-warm moxibustion)in treating IBS-D(spleen deficiency and dampness excess syndrome)with the first-line treatment.Methods:In this prospective,parallel,randomized controlled trial(RCT)protocol,patients will be randomly allocated for 4-week treatment or control therapies and then 4-week follow-up in both groups.We will use Irritable Bowel Syndrome-Symptom Severity Scale(IBS-SSS)score,Irritable Bowel Syndrome-Quality of Life(IBS-QOL)score,serum brain-gut peptide levels,and traditional Chinese medicine(TCM)syndrome scale score to produce more evidence on IBS-D treatment with moxibustion.Finally,we will use SPSS 22.0 software to statistically analyze the data.Discussion:Mild-warm moxibustion is a complementary alternative therapy that fits with the pathogenesis of IBS-D.We hope to see more clinical evidence for mild-warm moxibustion against IBS-D that this RCT supported. 展开更多
关键词 IBS-D mild-warm moxibustion protocol complementary alternative therapy randomized controlled trial
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Cloud control for IIoT in a cloud-edge environment
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作者 YAN Ce XIA Yuanqing +1 位作者 YANG Hongjiu ZHAN Yufeng 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期1013-1027,共15页
The industrial Internet of Things(IIoT)is a new indus-trial idea that combines the latest information and communica-tion technologies with the industrial economy.In this paper,a cloud control structure is designed for... The industrial Internet of Things(IIoT)is a new indus-trial idea that combines the latest information and communica-tion technologies with the industrial economy.In this paper,a cloud control structure is designed for IIoT in cloud-edge envi-ronment with three modes of 5G.For 5G based IIoT,the time sensitive network(TSN)service is introduced in transmission network.A 5G logical TSN bridge is designed to transport TSN streams over 5G framework to achieve end-to-end configuration.For a transmission control protocol(TCP)model with nonlinear disturbance,time delay and uncertainties,a robust adaptive fuzzy sliding mode controller(AFSMC)is given with control rule parameters.IIoT workflows are made up of a series of subtasks that are linked by the dependencies between sensor datasets and task flows.IIoT workflow scheduling is a non-deterministic polynomial(NP)-hard problem in cloud-edge environment.An adaptive and non-local-convergent particle swarm optimization(ANCPSO)is designed with nonlinear inertia weight to avoid falling into local optimum,which can reduce the makespan and cost dramatically.Simulation and experiments demonstrate that ANCPSO has better performances than other classical algo-rithms. 展开更多
关键词 5G and time sensitive network(TSN) industrial Internet of Things(IIoT)workflow transmission control protocol(TCP)flows control cloud edge collaboration multi-objective optimal scheduling
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Functional and psychosocial effects of pulmonary Daoyin on patients with COPD in China:study protocol of a multicenter randomized controlled trial 被引量:15
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作者 Xue-qing Yu Jian-sheng Li +5 位作者 Su-yun Li Yang Xie Ming-hang Wang Hai-long Zhang Hai-feng Wang Zhi-wan Wang 《Journal of Integrative Medicine》 SCIE CAS CSCD 2013年第2期140-146,共7页
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major public health problem worldwide. Pulmonary rehabilitation (PR) is an established intervention for the management of patients with COPD. Exercise... BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major public health problem worldwide. Pulmonary rehabilitation (PR) is an established intervention for the management of patients with COPD. Exercise training is an important part of PR, and its effectiveness in patients with COPD is well established. However, alternative methods of PR training such as Daoyin have not been appropriately studied. Hence, alternative forms of exercise training that require less exercise equipment and no specific training place should be evaluated. This paper describes the study protocol of a clinical trial that aims to determine if pulmonary Daoyin training will improve the exercise capacity and psychosocial function of patients with COPD in China. METHODS AND DESIGN: A multicenter, randomized, controlled trial will be conducted. A total of 464 patients meeting the inclusion criteria will be enrolled into this study with 232 patients in each of the trial group and the control group. Based on patient education, patients in the trial group will receive pulmonary Daoyin and continue with their usual therapy for three months. In the control group, patients will continue with their usual therapy. The primary outcome measures are exercise capacity assessed by the six-minute walking distance test and lung function. Secondary outcomes include dyspnea and quality of life. Measurements will be taken at baseline (month 0) and after the study period (month 3). DISCUSSION: It is hypothesized that pulmonary Daoyin will have beneficial effects in improving exercise capacity and psychosocial function of patients with stable COPD, and will provide an alternative form of exercise training that is accessible for the large number of people with COPD. TRIAL REGISTRATION: This trial has been registered in ClinicalTrials.gov. The identifier is NCT01482000. 展开更多
关键词 chronic obstructive pulmonary disease DAOYIN randomized controlled trial study protocol
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Chinese herbal medicine Xinfeng Capsule in treatment of rheumatoid arthritis:study protocol of a multicenter randomized controlled trial 被引量:9
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作者 Jian Liu Chuan-bing Huang +5 位作者 Yuan Wang Gui-qin Xu Yuan-yuan Cheng Yun-xia Feng Lei Liu Ya-jun Qi 《Journal of Integrative Medicine》 SCIE CAS CSCD 2013年第6期428-434,共7页
BACKGROUND: Rheumatoid arthritis (RA), as a common systemic inflammatory autoimmune disease, affects approximately 1 in 100 individuals. Effective treatment for RA is not yet available because current research does... BACKGROUND: Rheumatoid arthritis (RA), as a common systemic inflammatory autoimmune disease, affects approximately 1 in 100 individuals. Effective treatment for RA is not yet available because current research does not have a clear understanding of the etiology and pathogenesis of RA. Xinfeng Capsule, a patent Chinese herbal medicine, has been used in the treatment of RA in recent years. Despite its reported clinical efficacy, there are no large-sample, multicenter, randomized trials that support the use of Xinfeng Capsule for RA. Therefore, we designed a randomized, double-blind, multicenter, placebo-controlled trial to assess the efficacy and safety of Xinfeng Capsule in the treatment of RA. METHODS AND DESIGN: This is a 12-week, randomized, placebo-controlled, double-blind, multicenter trial on the treatment of RA. The participants will be randomly assigned to the experimental group and the control group at a ratio of 1:1. Participants in the experimental group will receive Xinfeng Capsule and a pharmaceutical placebo (imitation leflunomide). The control group will receive leflunomide and an herbal placebo (imitation Xinfeng Capsule). The American College of Rheumatology (ACR) Criteria for RA will be used to measure the efficacy of the Xinfeng Capsule. The primary outcome measure will be the percentage of study participants who achieve an ACR 20% response rate (ACR20), which will be measured every 4 weeks after randomization. Secondary outcomes will include the ACR50 and ACR70 responses, the side effects of the medications, the Disease Activity Score 28, RA biomarkers, quality of life, and X-rays of the hands and wrists. The first four of the secondary outcomes will be measured every 4 weeks and the others will be measured at baseline and after 12 weeks of treatment. DISCUSSION: The result of this trial will help to evaluate whether Xinfeng Capsule is effective and safe in the treatment of RA. TRIAL REGISTRATION: This trial has been registered in ClinicalTrials.gov. The identifier is N CT01774877. 展开更多
关键词 Xinfeng Capsule rheumatoid arthritis double-blind method PLACEBOS ACRcriteria quality of life randomized controlled trials clinical protocols
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Evaluation on the efficacy and safety of Chinese herbal medication Xifeng Dingchan Pill in treating Parkinson's disease: study protocol of a multicenter, open-label, randomized active-controlled trial 被引量:7
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作者 Jie Zhang Yun-zhi Ma Xiao-ming Shen 《Journal of Integrative Medicine》 SCIE CAS CSCD 2013年第4期285-290,共6页
BACKGROUND: Parkinson's disease (PD) is a complicated disease, commonly diagnosed among the elderly, which leads to degeneration of the central nervous system. It presently lacks an effective therapy for its compl... BACKGROUND: Parkinson's disease (PD) is a complicated disease, commonly diagnosed among the elderly, which leads to degeneration of the central nervous system. It presently lacks an effective therapy for its complex pathogenesis. Adverse effects from Western drug-based medical intervention prevent long-term adherence to these therapies in many patients. Traditional Chinese medicine (TCM) has long been used to improve the treatment of PD by alleviating the toxic and adverse effects of Western drug-based intervention. Therefore, the aim of this study is to evaluate the efficacy and safety of Xifeng Dingchan Pill (XFDCP), a compound traditional Chinese herbal medicine, taken in conjunction with Western medicine in the treatment of PD patients at different stages in the progression of the disease. METHODS AND DESIGN: This is a multicenter, randomized controlled trial. In total, 320 patients with early- (n = 160) and middle-stage PD (n = 160) will be enrolled and divided evenly into control and trial groups. Of the 160 patients with early-stage PD, the trial group (n = 80) will be given XFDCP, and the control group (n = 80) will be given Madopar. Of the 160 patients with middle-stage PD, the trial group (n = 80) will be given XFDCP combined with Madopar and Piribedil, and the control group (n = 80) will be given Madopar and Piribedil. The Unified Parkinson's Disease Rating Scale scores, TCM symptoms scores, quality of life, change of Madopar's dosage and the toxic and adverse effects of Madopar will be observed during a 3-month treatment period and through a further 6-month follow-up period. DISCUSSION: It is hypothesized that XFDCP, combined with Madopar and Piribedil, will have beneficial effects on patients with PD. The results of this study will provide evidence for developing a comprehensive therapy regimen, which can delay the progress of the disease and improve the quality of life for PD patients in different stages. TRIAL REGISTRATION: This trial has been registered in the Chinese Clinical Trial Registry with the identifer ChiCTR-TRC-12002150. 展开更多
关键词 Parkinson disease LEVODOPA drugs Chinese herbal drug toxicity randomized controlled trial clinical protocols
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Consensus tracking protocol and formation control of multi-agent systems with switching topology 被引量:13
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作者 年晓红 苏赛军 潘欢 《Journal of Central South University》 SCIE EI CAS 2011年第4期1178-1183,共6页
Consensus tracking control problems for single-integrator dynamics of multi-agent systems with switching topology are investigated. In order to design effective consensus tracking protocols for a more general class of... Consensus tracking control problems for single-integrator dynamics of multi-agent systems with switching topology are investigated. In order to design effective consensus tracking protocols for a more general class of networks, which are aimed at ensuring that the concerned states of agents converge to a constant or time-varying reference state, new consensus tracking protocols with a constant and time-varying reference state are proposed, respectively. Particularly, by contrast with spanning tree, an improved condition of switching interaction topology is presented. And then, convergence analysis of two consensus tracking protocols is provided by Lyapunov stability theory. Moreover, consensus tracking protocol with a time-varying reference state is extended to achieve the fbrmation control. By introducing formation structure set, each agent can gain its individual desired trajectory. Finally, several simulations are worked out to illustrate the effectiveness of theoretical results. The test results show that the states of agents can converge to a desired constant or time-varying reference state. In addition, by selecting appropriate structure set, agents can maintain the expected formation under random switching interaction topologies. 展开更多
关键词 multi-agent system consensus protocols formation control switching topology
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Human umbilical cord mesenchymal stem cells to treat spinal cord injury in the early chronic phase: study protocol for a prospective, multicenter, randomized, placebo-controlled, single-blinded clinical trial 被引量:9
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作者 Yang Yang Mao Pang +5 位作者 Yu-Yong Chen Liang-Ming Zhang Hao Liu Jun Tan Bin Liu Li-Min Rong 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第8期1532-1538,共7页
Human umbilical cord mesenchymal stem cells(hUC-MSCs)support revascularization,inhibition of inflammation,regulation of apoptosis,and promotion of the release of beneficial factors.Thus,they are regarded as a promisin... Human umbilical cord mesenchymal stem cells(hUC-MSCs)support revascularization,inhibition of inflammation,regulation of apoptosis,and promotion of the release of beneficial factors.Thus,they are regarded as a promising candidate for the treatment of intractable spinal cord injury(SCI).Clinical studies on patients with early chronic SCI(from 2 months to 1 year post-injury),which is clinically common,are rare;therefore,we will conduct a prospective,multicenter,randomized,placebo-controlled,single-blinded clinical trial at the Third Affiliated Hospital of Sun Yat-sen University,West China Hospital of Sichuan University,and Shanghai East Hospital,Tongji University School of Medicine,China.The trial plans to recruit 66 early chronic SCI patients.Eligible patients will undergo randomization at a 2:1 ratio to two arms:the observation group and the control group.Subjects in the observation group will receive four intrathecal transplantations of stem cells,with a dosage of 1×106/kg,at one calendar month intervals.Subjects in the control group will receive intrathecal administrations of 10 mL sterile normal saline in place of the stem cell transplantations.Clinical safety will be assessed by the analysis of adverse events and laboratory tests.The American Spinal Injury Association(ASIA)total score will be the primary efficacy endpoint,and the secondary efficacy outcomes will be the following:ASIA impairment scale,International Association of Neural Restoration-Spinal Cord Injury Functional Rating Scale,muscle tension,electromyogram,cortical motor and cortical sensory evoked potentials,residual urine volume,magnetic resonance imaging–diffusion tensor imaging,T cell subtypes in serum,neurotrophic factors and inflammatory factors in both serum and cerebrospinal fluid.All evaluations will be performed at 1,3,6,and 12 months following the final intrathecal administration.During the entire study procedure,all adverse events will be reported as soon as they are noted.This trial is designed to evaluate the clinical safety and efficacy of subarachnoid transplantation of hUC-MSCs to treat early chronic SCI.Moreover,it will establish whether cytotherapy can ameliorate local hostile microenvironments,promote tracking fiber regeneration,and strengthen spinal conduction ability,thus improving overall motor,sensory,and micturition/defecation function in patients with early chronic SCI.This study was approved by the Stem Cell Research Ethics Committee of the Third Affiliated Hospital of Sun Yat-sen University,China(approval No.[2018]-02)on March 30,2018,and was registered with ClinicalTrials.gov(registration No.NCT03521323)on April 12,2018.The revised trial protocol(protocol version 4.0)was approved by the Stem Cell Research Ethics Committee of the Third Affiliated Hospital of Sun Yat-sen University,China(approval No.[2019]-10)on February 25,2019,and released on ClinicalTrials.gov on April 29,2019. 展开更多
关键词 clinical study early chronic phase efficacy human umbilical cord mesenchymal stem cell multicenter trial prospective study randomized controlled trial safety spinal cord injury study protocol
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MULTIPLE ELECTRONIC CONTROL UNITS CALIBRATION SYSTEM BASED ON EXPLICIT CALIBRATION PROTOCOL AND J1939 PROTOCOL 被引量:3
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作者 ZHU Keqing XU Quankui YANG Lin ZHUO Bin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第1期42-46,共5页
The rising number of electronic control units (ECUs) in vehicles and the decreasing time to market have led to the need for advanced methods of calibration. A multi-ECU calibration system was developed based on the ... The rising number of electronic control units (ECUs) in vehicles and the decreasing time to market have led to the need for advanced methods of calibration. A multi-ECU calibration system was developed based on the explicit calibration protocol (XCP) and J1939 communication protocol to satisfy the need of calibrating multiple ECUs simultaneously. The messages in the controller area network (CAN) are defined in the J1939 protocol. Each CAN node can get its own calibration messages and information from other ECUs, and block other messages by qualifying the CAN messages with priority, source or destination address. The data field of the calibration message is designed with the XCP, with CAN acting as the transport layer. The calibration sessions are setup with the event-triggered XCP driver in the master node and the responding XCP driver in the slave nodes. Mirroring calibration variables from ROM to RAM enables the user to calibrate ECUs online. The application example shows that the multi-ECU calibration system can calibrate multiple ECUs simultaneously, and the main program can also accomplish its calculation and send commands to the actuators in time. By the multi-ECU calibration system, the calibration effort and time can be reduced and the variables in ECU can get a better match with the variables of other ECUs. 展开更多
关键词 Electronic control unit (ECU) Calibration Explicit calibration protocol (XCP) J1939 communication protocol controlled area network (CAN)
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Neural-Network-Based Control for Discrete-Time Nonlinear Systems with Input Saturation Under Stochastic Communication Protocol 被引量:10
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作者 Xueli Wang Derui Ding +1 位作者 Hongli Dong Xian-Ming Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第4期766-778,共13页
In this paper,an adaptive dynamic programming(ADP)strategy is investigated for discrete-time nonlinear systems with unknown nonlinear dynamics subject to input saturation.To save the communication resources between th... In this paper,an adaptive dynamic programming(ADP)strategy is investigated for discrete-time nonlinear systems with unknown nonlinear dynamics subject to input saturation.To save the communication resources between the controller and the actuators,stochastic communication protocols(SCPs)are adopted to schedule the control signal,and therefore the closed-loop system is essentially a protocol-induced switching system.A neural network(NN)-based identifier with a robust term is exploited for approximating the unknown nonlinear system,and a set of switch-based updating rules with an additional tunable parameter of NN weights are developed with the help of the gradient descent.By virtue of a novel Lyapunov function,a sufficient condition is proposed to achieve the stability of both system identification errors and the update dynamics of NN weights.Then,a value iterative ADP algorithm in an offline way is proposed to solve the optimal control of protocol-induced switching systems with saturation constraints,and the convergence is profoundly discussed in light of mathematical induction.Furthermore,an actor-critic NN scheme is developed to approximate the control law and the proposed performance index function in the framework of ADP,and the stability of the closed-loop system is analyzed in view of the Lyapunov theory.Finally,the numerical simulation results are presented to demonstrate the effectiveness of the proposed control scheme. 展开更多
关键词 Adaptive dynamic programming(ADP) constrained inputs neural network(NN) stochastic communication protocols(SCPs) suboptimal control
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A hierarchical architecture of centralized monitoring and controlling system and its high-performance and interoperability protocol 被引量:3
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作者 黄理灿 吴朝晖 潘云鹤 《Journal of Zhejiang University Science》 CSCD 2004年第1期22-30,共9页
This paper describes a hierarchical architecture and a high-performance and interoperability protocol for centralized monitoring and controlling systems (CMCS) . The protocol we proposed can interoperate different mon... This paper describes a hierarchical architecture and a high-performance and interoperability protocol for centralized monitoring and controlling systems (CMCS) . The protocol we proposed can interoperate different monitoring and controlling systems constructed by different companies, each with different functions and communication protocols. The protocol reduces the amount of traffic and has real-time and high-perfor-mance advantages. The protocol was implemented in CMCS for telecommunication power supply and air-condi-tioner used by the Telecommunication Bureau of Zhejiang Province. This paper deals with the hierarchical architecture and function of CMCS and packet format, command ID, and SDL description of its protocol. We also discuss the properties of the interoperability and performance of the protocol in this paper. 展开更多
关键词 Monitoring and controlling system protocol ARCHITECTURE
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Self-organization of Reconfigurable Protocol Stack for Networked Control Systems 被引量:1
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作者 Chun-Jie Zhou Hui Chen Yuan-Qing Qin Yu-Feng Shi Guang-Can Yu 《International Journal of Automation and computing》 EI 2011年第2期221-235,共15页
In networked control systems (NCS),the control performance depends on not only the control algorithm but also the communication protocol stack.The performance degradation introduced by the heterogeneous and dynamic ... In networked control systems (NCS),the control performance depends on not only the control algorithm but also the communication protocol stack.The performance degradation introduced by the heterogeneous and dynamic communication environment has intensified the need for the reconfigurable protocol stack.In this paper,a novel architecture for the reconfigurable protocol stack is proposed,which is a unified specification of the protocol components and service interfaces supporting both static and dynamic reconfiguration for existing industrial communication standards.Within the architecture,a triple-level self-organization structure is designed to manage the dynamic reconfiguration procedure based on information exchanges inside and outside the protocol stack.Especially,the protocol stack can be self-adaptive to various environment and system requirements through the reconfiguration of working mode,routing and scheduling table.Finally,the study on the protocol of dynamic address management is conducted for the system of controller area network (CAN).The results show the efficiency of our self-organizing architecture for the implementation of a reconfigurable protocol stack. 展开更多
关键词 Networked control system (NCS) communication network SELF-ORGANIZATION protocol stack RECONFIGURATION
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A Quantitative Security Metric Model for Security Controls:Secure Virtual Machine Migration Protocol as Target of Assessment 被引量:1
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作者 Tayyaba Zeb Muhammad Yousaf +1 位作者 Humaira Afzal Muhammad Rafiq Mufti 《China Communications》 SCIE CSCD 2018年第8期126-140,共15页
Quantitative security metrics are desirable for measuring the performance of information security controls. Security metrics help to make functional and business decisions for improving the performance and cost of the... Quantitative security metrics are desirable for measuring the performance of information security controls. Security metrics help to make functional and business decisions for improving the performance and cost of the security controls. However, defining enterprise-level security metrics has already been listed as one of the hard problems in the Info Sec Research Council's hard problems list. Almost all the efforts in defining absolute security metrics for the enterprise security have not been proved fruitful. At the same time, with the maturity of the security industry, there has been a continuous emphasis from the regulatory bodies on establishing measurable security metrics. This paper addresses this need and proposes a relative security metric model that derives three quantitative security metrics named Attack Resiliency Measure(ARM), Performance Improvement Factor(PIF), and Cost/Benefit Measure(CBM) for measuring the performance of the security controls. For the effectiveness evaluation of the proposed security metrics, we took the secure virtual machine(VM) migration protocol as the target of assessment. The virtual-ization technologies are rapidly changing the landscape of the computing world. Devising security metrics for virtualized environment is even more challenging. As secure virtual machine migration is an evolving area and no standard protocol is available specifically for secure VM migration. This paper took the secure virtual machine migration protocol as the target of assessment and applied the proposed relative security metric model for measuring the Attack Resiliency Measure, Performance Improvement Factor, and Cost/Benefit Measure of the secure VM migration protocol. 展开更多
关键词 attack resiliency measure cost-benefit measure performance improvement factor security assessment formal verification security controls security metrics virtual machine migration protocol
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Analysis and Application of Covert Channels of Internet Control Message Protocol
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作者 ZHOU Xueguang ZHANG Huanguo 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1857-1861,共5页
Based on the analysis of the covert channel's working mechanism of the internet control message protocol (ICMP) in internet protocol version 4 (IPv4) and Internet Protocol version 6 (IPv6), the ICMP covert cha... Based on the analysis of the covert channel's working mechanism of the internet control message protocol (ICMP) in internet protocol version 4 (IPv4) and Internet Protocol version 6 (IPv6), the ICMP covert channd's algorithms of the IPv4 and IPv6 are presented, which enable automatic channeling upon IPv4/v6 nodes with non-IPv4-compatible address, and the key transmission is achieved by using this channel in the embedded Internet terminal. The result shows that the covert channel's algorithm, which we implemented if, set correct, the messages of this covert channel might go through the gateway and enter the local area network. 展开更多
关键词 internet control message protocol (ICMP) covert channel embedded Internet terminal (EIT) algorithm information security
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EVCP:a convergence time improved high-speed transport congestion control protocol
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作者 LU Guang WANG Yong-chao ZHU Miao-liang 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第6期849-856,共8页
The Internet evolves to incorporate very-high-bandwidth optical links and more large-delay satellite links. TCP faces new challenges in this unique environment. Theory and experiments showed that TCP becomes inefficie... The Internet evolves to incorporate very-high-bandwidth optical links and more large-delay satellite links. TCP faces new challenges in this unique environment. Theory and experiments showed that TCP becomes inefficient and is prone to be unstable as the per-flow product of bandwidth and latency increases, regardless of the queuing scheme. Variable-structure congestion Control Protocol (VCP) is proposed to address these problems. However, VCP has problem in terms of convergence time, i.e., it takes a long time for a new VCP flow to achieve fair bandwidth allocation if the existing VCP flows have large con- gestion windows. This paper proposed an Extended Variable-structure congestion Control Protocol (EVCP), which adopted a convergence controller. The basic idea of convergence controller is that if a flow has larger window than its fair window, its congestion window should be decreased more aggressively than usual in Multiplicative Decrease (MD) phase. Simulations showed that EVCP has better performance in terms of convergence time while keeping the advantages of VCP. 展开更多
关键词 Congestion control Variable-structure congestion control protocol (VCP) High-speed network
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Hierarchical hybrid control network design based on LON and master-slave RS-422/485 protocol
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作者 彭可 陈际达 陈岚 《Journal of Central South University of Technology》 2002年第3期202-207,共6页
Aiming at the weaknesses of LON bus, combining the coexistence of fieldbus and DCS (Distribu ted Control Systems) in control networks, the authors introduce a hierarchical hybrid control network design based on LON an... Aiming at the weaknesses of LON bus, combining the coexistence of fieldbus and DCS (Distribu ted Control Systems) in control networks, the authors introduce a hierarchical hybrid control network design based on LON and master slave RS 422/485 protocol. This design adopts LON as the trunk, master slave RS 422/485 control networks are connected to LON as special subnets by dedicated gateways. It is an implementation method for isomerous control network integration. Data management is ranked according to real time requirements for different network data. The core components, such as control network nodes, router and gateway, are detailed in the paper. The design utilizes both communication advantage of LonWorks technology and the more powerful control ability of universal MCUs or PLCs, thus it greatly increases system response speed and performance cost ratio. 展开更多
关键词 LON fieldbus MASTER-SLAVE RS-422/485 protocol HIERARCHICAL hybrid control NETWORKS router gateway NETWORKS integration
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Dynamic Characteristics of Explicit Control Protocol
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作者 程双梅 李建华 郭传雄 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第1期60-63,共4页
The dynamic characteristics of eplicit control protocol (XCP) were investigated with single bottleneck on the microscopic time-scale. Analysis and simulation results show that the bandwidth utilization of an XCP bottl... The dynamic characteristics of eplicit control protocol (XCP) were investigated with single bottleneck on the microscopic time-scale. Analysis and simulation results show that the bandwidth utilization of an XCP bottleneck link converges to 1 at exponential rate, persistent congestion cannot occur at the bottleneck link, and throughput of an arbitrary subset of XCP flows at the bottleneck link converges to its fair share in exponential rate. The XCP has high bandwidth utilization and good fairness properties. 展开更多
关键词 eplicit control protocol real-time analysis FAIRNESS
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Improving Throughput of Transmission Control Protocol Using Cross LayerApproach
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作者 Jansi Rani Sella Veluswami 《Computer Systems Science & Engineering》 SCIE EI 2022年第12期1231-1239,共9页
Most of the internet users connect through wireless networks. Majorpart of internet traffic is carried by Transmission Control Protocol (TCP). It hassome design constraints while operated across wireless networks. TCP... Most of the internet users connect through wireless networks. Majorpart of internet traffic is carried by Transmission Control Protocol (TCP). It hassome design constraints while operated across wireless networks. TCP is the traditional predominant protocol designed for wired networks. To control congestionin the network, TCP used acknowledgment to delivery of packets by the end host.In wired network, packet loss signals congestion in the network. But rather inwireless networks, loss is mainly because of the wireless characteristics such asfading, signal strength etc. When a packet travels across wired and wireless networks, TCP congestion control theory faces problem during handshake betweenthem. This paper focuses on finding this misinterpretation of the losses using crosslayer approach. This paper focuses on increasing bandwidth usage by improvingTCP throughput in wireless environments using cross layer approach and hencenamed the proposed system as CRLTCP. TCP misinterprets wireless loss as congestion loss and unnecessarily reduces congestion window size. Using the signalstrength and frame error rate, the type of loss is identified and accordingly theresponse of TCP is modified. The results show that there is a significant improvement in the throughput of proposed TCP upon which bandwidth usage isincreased. 展开更多
关键词 BANDWIDTH wireless networks transmission control protocol THROUGHPUT
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ICMPTend: Internet Control Message Protocol Covert Tunnel Attack Intent Detector
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作者 Tengfei Tu Wei Yin +4 位作者 Hua Zhang Xingyu Zeng Xiaoxiang Deng Yuchen Zhou Xu Liu 《Computers, Materials & Continua》 SCIE EI 2022年第5期2315-2331,共17页
The Internet Control Message Protocol(ICMP)covert tunnel refers to a network attack that encapsulates malicious data in the data part of the ICMP protocol for transmission.Its concealment is stronger and it is not eas... The Internet Control Message Protocol(ICMP)covert tunnel refers to a network attack that encapsulates malicious data in the data part of the ICMP protocol for transmission.Its concealment is stronger and it is not easy to be discovered.Most detection methods are detecting the existence of channels instead of clarifying specific attack intentions.In this paper,we propose an ICMP covert tunnel attack intent detection framework ICMPTend,which includes five steps:data collection,feature dictionary construction,data preprocessing,model construction,and attack intent prediction.ICMPTend can detect a variety of attack intentions,such as shell attacks,sensitive directory access,communication protocol traffic theft,filling tunnel reserved words,and other common network attacks.We extract features from five types of attack intent found in ICMP channels.We build a multi-dimensional dictionary of malicious features,including shell attacks,sensitive directory access,communication protocol traffic theft,filling tunnel reserved words,and other common network attack keywords.For the high-dimensional and independent characteristics of ICMP traffic,we use a support vector machine(SVM)as a multi-class classifier.The experimental results show that the average accuracy of ICMPTend is 92%,training ICMPTend only takes 55 s,and the prediction time is only 2 s,which can effectively identify the attack intention of ICMP. 展开更多
关键词 Internet control message protocol support vector machine covert tunnel network analysis
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DQCA:a New Medium Access Control Protocol for MANs
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作者 孙海荣 《High Technology Letters》 EI CAS 1996年第1期42-46,共5页
A new medium access control protocol for MANs named DQCA(Distributed QueueCyclic Access)is presented in this paper.When the users of DQCA MAN transfer long files,the network will reach a steady state which is fair aft... A new medium access control protocol for MANs named DQCA(Distributed QueueCyclic Access)is presented in this paper.When the users of DQCA MAN transfer long files,the network will reach a steady state which is fair after a transient period.The transient pe-riod is shorter than that of DQDB.DQCA MAN has the flexibility in bandwidth allocation:the users can achieve different throughputs if the parameters,Pmax(i),are set to be differ-ent.The implementation of priority mechanism is simpler than that of DQDB. 展开更多
关键词 Metropolitan area network Medium access control protocol DQDB
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Distributed multichannel medium access control protocol without common control channel for single-hop cognitive radio networks
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作者 徐贵森 谭学治 《Journal of Central South University》 SCIE EI CAS 2011年第5期1532-1544,共13页
A novel distributed cognitive radio multichannel medium access protocol without common control channel was proposed.The protocol divided a transmission interval into two parts for exchanging control information and da... A novel distributed cognitive radio multichannel medium access protocol without common control channel was proposed.The protocol divided a transmission interval into two parts for exchanging control information and data,respectively.In addition to evaluating system saturation throughput of the proposed protocol,a three-dimensional multi channel Markov chain model to describe the sate of the cognitive users (CUs) in dynamic spectrum access was presented.The proposed analysis was applied to the packet transmission schemes employed by the basic,RTS/CTS access mechanism adopted in the normal IEEE 802.11.Analyzing the advantage of the two methods,a hybrid access mechanism was proposed to improve the system throughput.The simulation results show that the experiment results are close to the value computed by the model (less than 5%),and the proposed protocol significantly improves the performance of the system throughput by borrowing the licensed spectrum.By analyzing the dependence of throughput on system parameters,hybrid mechanism dynamically selecting access mechanism can maintain high throughput. 展开更多
关键词 cognitive radio network multichannel cognitive radio MAC (medium access control protocols performance evaluation saturation throughput
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