With the rapid development of the embedded technology, research and implement of the Internet of things will be a new technology revolution, yet the implement of the Internet of things is on the base of the communicat...With the rapid development of the embedded technology, research and implement of the Internet of things will be a new technology revolution, yet the implement of the Internet of things is on the base of the communication between the things. For this reason, realizing the function of communication between singlechip is particularly important. Based on the characteristics of the embedded microcontroller, we analyzed the traditional PC TCP/IP protocol, and appropriately tailored TCP/IP protocol cluster on the basis of the characteristics of embedded singlechip. At last, we realized the reduced TCP/IP protocol cluster suitable for embedded singlechip, on AVR singlechip platform.展开更多
Two significant issues in Internet-based networked control systems （ INCSs）, transport performance of different protocols and security breach from Internet side, are investigated. First, for improving the performanc...Two significant issues in Internet-based networked control systems （ INCSs）, transport performance of different protocols and security breach from Internet side, are investigated. First, for improving the performance of data transmission, user datagram protocol （UDP） is adopted as the main stand for controllers and plants using INCSs. Second, a dual-channel secure transmission scheme （DCSTS）based on data transmission characteristics of INCSs is proposed, in which a raw UDP channel and a secure TCP （transmission control protocol） connection making use of SSL/TLS （secure sockets layer/transport layer security） are included. Further, a networked control protocol （NCP） at application layer for supporting DCSTS between the controllers and plants in INCSs is designed, and it also aims at providing a universal communication mechanism for interoperability of devices among the networked control laboratories in Beijing Institute of Technology of China, Central South University of China and Tokyo University of Technology of Japan. By means of a networked single-degree-of-free- dom robot arm, an INCS under the new protocol and security environment is created. Compared with systems such as IPSec or SSL/TLS, which may cause more than 91% network throughput deduction, the new DCSTS protocol may yield results ten times better, being just 5.67%.展开更多
电力监控系统环境中存在过多噪声因素干扰,导致通信效率和质量低。为此,提出一种基于传输控制协议/网际协议(transmission control protocol/internet protocol,TCP/IP)与关联规则的多线程通信算法。将背景噪声看作电力监控信号的突变现...电力监控系统环境中存在过多噪声因素干扰,导致通信效率和质量低。为此,提出一种基于传输控制协议/网际协议(transmission control protocol/internet protocol,TCP/IP)与关联规则的多线程通信算法。将背景噪声看作电力监控信号的突变现象,查找回应突变函数的信号值,利用谐波分离算法,去除背景噪声。根据不同线程的传输特点,采用TCP/IP协议建立通信程序包,分别设置句柄、终止、挂起以及执行函数,为不同线程的通信数据,匹配不同的通信协议。试验结果证明:对电力监控系统源设备的传输信号多线程通信时,通信信号波频变化最为平稳,在0~2000 s的采样区间内,未出现传输为0现象;对背景噪声去噪后,波形相比原始信号变化明显较为稳定,没有出现过高或过低的幅值变化。所提方法通信信号表达平稳、效率较高,对原始信号的保留效果较好,去噪能力很强。展开更多
Transmission Control Protocol (TCP) optimization in Mobile Ad hoc NETworks (MANETs) is a challenging issue because of some unique characteristics of MANETs. In this paper,a new end-to-end mechanism based on multiple m...Transmission Control Protocol (TCP) optimization in Mobile Ad hoc NETworks (MANETs) is a challenging issue because of some unique characteristics of MANETs. In this paper,a new end-to-end mechanism based on multiple metrics measurement is proposed to improve TCP performance in MANETs. Multi-metric Measurement based Enhancement of TCP (MME-TCP) designs the metrics and the identification algorithm according to the characteristics of MANETs and the experiment results. Furthermore,these metrics are measured at the sender node to reduce the overhead of control information over networks. Simulation results show that MME-TCP mechanism achieves a significant performance improvement over standard TCP in MANETs.展开更多
The goal of this paper is to propose a fast and secure multi-stage image compression-decompression system by using a wireless network between two Personal Computers (PCs). In this paper, the Principal Component Analys...The goal of this paper is to propose a fast and secure multi-stage image compression-decompression system by using a wireless network between two Personal Computers (PCs). In this paper, the Principal Component Analysis (PCA) technique is used for multi-stage image compression and Inverse Principal Component Analysis (IPCA) for multi-stage image decompression. The first step of the proposed system is to select the input image, the second step is to perform PCA up to 9 times on the input image, this compression, and after multi-stage compression process then the third step begins by transforming across wireless Ad hoc Network (WANET) to the second computing device, forth step start with multi-stage decompression process up 9 times. The proposed system for different images is transferred over the wireless network using Transmission Control Protocol/Internet Protocol (TCP/IP), which is programmed using the network role property of the MATLAB program. The proposed system implements 25 different images correctly (100%). The main contribution of this paper is that we are dealing with the black image at the end of the compressed process ad start with a black image at the start of the decompressed process of this proposed system. In this work, the compressed and uncompressed images are compared with each other in their size and transmission time. This system can be very useful in networks because they provide a high level of protection to the transmitted data from hackers because they cannot guess how much the image has been compressed or what kind of information the image represents.展开更多
随着网际互连协议(Internet Protocol,IP)网络在广播电视信号传输中的广泛应用,网络拥塞和信号质量下降等问题日益突出。针对上述挑战,深入分析IP组播、服务质量(Quality of Service,QoS)机制及网络编码等关键技术,在此基础上提出一种...随着网际互连协议(Internet Protocol,IP)网络在广播电视信号传输中的广泛应用,网络拥塞和信号质量下降等问题日益突出。针对上述挑战,深入分析IP组播、服务质量(Quality of Service,QoS)机制及网络编码等关键技术,在此基础上提出一种改进的自适应比特率算法。该算法结合网络状态感知和内容复杂度评估,可实现传输参数的动态调整。通过在模拟网络环境中进行大规模实验,结果表明所提算法在带宽利用率、传输时延及画质方面均有显著提升。此次研究成果为IP网络下广播电视信号的高效传输提供了新的技术方案。展开更多
随着智能电网的发展,电力系统对保护设备提出更高要求。文章设计一种基于Modbus传输控制协议(Modbus Transmission Control Protocol,Modbus-TCP)的智能断路器温度与电流双重保护系统,集成多参量融合传感技术与人工智能算法,有效提升断...随着智能电网的发展,电力系统对保护设备提出更高要求。文章设计一种基于Modbus传输控制协议(Modbus Transmission Control Protocol,Modbus-TCP)的智能断路器温度与电流双重保护系统,集成多参量融合传感技术与人工智能算法,有效提升断路器的保护性能和响应速度。该系统采用高精度温度与电流传感器,利用Modbus-TCP协议实现高效、可靠的通信。实验结果表明,该系统在过流保护、温度测量精度、通信时延等方面表现出色,满足现代配电自动化的技术需求。展开更多
文摘With the rapid development of the embedded technology, research and implement of the Internet of things will be a new technology revolution, yet the implement of the Internet of things is on the base of the communication between the things. For this reason, realizing the function of communication between singlechip is particularly important. Based on the characteristics of the embedded microcontroller, we analyzed the traditional PC TCP/IP protocol, and appropriately tailored TCP/IP protocol cluster on the basis of the characteristics of embedded singlechip. At last, we realized the reduced TCP/IP protocol cluster suitable for embedded singlechip, on AVR singlechip platform.
文摘Two significant issues in Internet-based networked control systems （ INCSs）, transport performance of different protocols and security breach from Internet side, are investigated. First, for improving the performance of data transmission, user datagram protocol （UDP） is adopted as the main stand for controllers and plants using INCSs. Second, a dual-channel secure transmission scheme （DCSTS）based on data transmission characteristics of INCSs is proposed, in which a raw UDP channel and a secure TCP （transmission control protocol） connection making use of SSL/TLS （secure sockets layer/transport layer security） are included. Further, a networked control protocol （NCP） at application layer for supporting DCSTS between the controllers and plants in INCSs is designed, and it also aims at providing a universal communication mechanism for interoperability of devices among the networked control laboratories in Beijing Institute of Technology of China, Central South University of China and Tokyo University of Technology of Japan. By means of a networked single-degree-of-free- dom robot arm, an INCS under the new protocol and security environment is created. Compared with systems such as IPSec or SSL/TLS, which may cause more than 91% network throughput deduction, the new DCSTS protocol may yield results ten times better, being just 5.67%.
文摘电力监控系统环境中存在过多噪声因素干扰,导致通信效率和质量低。为此,提出一种基于传输控制协议/网际协议(transmission control protocol/internet protocol,TCP/IP)与关联规则的多线程通信算法。将背景噪声看作电力监控信号的突变现象,查找回应突变函数的信号值,利用谐波分离算法,去除背景噪声。根据不同线程的传输特点,采用TCP/IP协议建立通信程序包,分别设置句柄、终止、挂起以及执行函数,为不同线程的通信数据,匹配不同的通信协议。试验结果证明:对电力监控系统源设备的传输信号多线程通信时,通信信号波频变化最为平稳,在0~2000 s的采样区间内,未出现传输为0现象;对背景噪声去噪后,波形相比原始信号变化明显较为稳定,没有出现过高或过低的幅值变化。所提方法通信信号表达平稳、效率较高,对原始信号的保留效果较好,去噪能力很强。
基金Supported by the National Natural Science Foundation of China (No.60496314)the Chinese 863 National High Technology Program (No.2002AA783043).
文摘Transmission Control Protocol (TCP) optimization in Mobile Ad hoc NETworks (MANETs) is a challenging issue because of some unique characteristics of MANETs. In this paper,a new end-to-end mechanism based on multiple metrics measurement is proposed to improve TCP performance in MANETs. Multi-metric Measurement based Enhancement of TCP (MME-TCP) designs the metrics and the identification algorithm according to the characteristics of MANETs and the experiment results. Furthermore,these metrics are measured at the sender node to reduce the overhead of control information over networks. Simulation results show that MME-TCP mechanism achieves a significant performance improvement over standard TCP in MANETs.
文摘The goal of this paper is to propose a fast and secure multi-stage image compression-decompression system by using a wireless network between two Personal Computers (PCs). In this paper, the Principal Component Analysis (PCA) technique is used for multi-stage image compression and Inverse Principal Component Analysis (IPCA) for multi-stage image decompression. The first step of the proposed system is to select the input image, the second step is to perform PCA up to 9 times on the input image, this compression, and after multi-stage compression process then the third step begins by transforming across wireless Ad hoc Network (WANET) to the second computing device, forth step start with multi-stage decompression process up 9 times. The proposed system for different images is transferred over the wireless network using Transmission Control Protocol/Internet Protocol (TCP/IP), which is programmed using the network role property of the MATLAB program. The proposed system implements 25 different images correctly (100%). The main contribution of this paper is that we are dealing with the black image at the end of the compressed process ad start with a black image at the start of the decompressed process of this proposed system. In this work, the compressed and uncompressed images are compared with each other in their size and transmission time. This system can be very useful in networks because they provide a high level of protection to the transmitted data from hackers because they cannot guess how much the image has been compressed or what kind of information the image represents.
文摘随着网际互连协议(Internet Protocol,IP)网络在广播电视信号传输中的广泛应用,网络拥塞和信号质量下降等问题日益突出。针对上述挑战,深入分析IP组播、服务质量(Quality of Service,QoS)机制及网络编码等关键技术,在此基础上提出一种改进的自适应比特率算法。该算法结合网络状态感知和内容复杂度评估,可实现传输参数的动态调整。通过在模拟网络环境中进行大规模实验,结果表明所提算法在带宽利用率、传输时延及画质方面均有显著提升。此次研究成果为IP网络下广播电视信号的高效传输提供了新的技术方案。
文摘随着智能电网的发展,电力系统对保护设备提出更高要求。文章设计一种基于Modbus传输控制协议(Modbus Transmission Control Protocol,Modbus-TCP)的智能断路器温度与电流双重保护系统,集成多参量融合传感技术与人工智能算法,有效提升断路器的保护性能和响应速度。该系统采用高精度温度与电流传感器,利用Modbus-TCP协议实现高效、可靠的通信。实验结果表明,该系统在过流保护、温度测量精度、通信时延等方面表现出色,满足现代配电自动化的技术需求。
