In wireless sensor networks, energy efficiency is a dominating design criterion. One way to reduce power consumption is to design energy efficient MAC protocols. In this paper, we combine the MAC protocol, BMA, with cooperative diversity techniques, and propose a new MAC protocol, CD-BMA. Simulation results showed that the proposed protocol can obtain better performance in capacity and energy efficiency.

According to the network data of mobile packet domain in backbone network, this article analyzes the correlation model of network load index in mobile packet domain. Based on the mobile service and analysis model of user behaviors, in this paper we proposed a correlation model and curve model on total traffic and average sessions, providing a theoretical support for the monitoring and traffic grooming of backbone network.

A WSN (Wireless Sensor Network) node self-locating means which utilized the position information of anchor nodes is proposed in this paper. There are two types of nodes in the objective network of the means. The first type is the anchor node that equipped GPS (Global Position System) unit, their exact position can be gained. The second type is normal node that supports RSS (Received Signal Strength) based ranging. With the help of anchor node, the normal nodes fulfill a low complexity, coarse-grained, RSS ranging based fuzzy logical locating algorithm, to determine their own positions. Theoretical analysis showed that, the proposed means can provide fine location accuracy with a relative low cost and complexity.

Under the circumstances that wireless sensor network ( WSN) nodes are deployed in a vast re-gion and the node density is low, the existing node location algorithms are not optimum selections. A WSN node self-locating algorithm which utilized the directivity of smart antenna is proposed. There are two types of nodes in the objective network of the means. The first type is central node that equipped with global position system ( GPS) unit and smart antenna. The second type is normal node that equipped with high frequency crystal oscillator. Normal node can support time of arrival ( TOA) based ranging. With the help of directional locating signal sent by central node,a normal node can estimate the angle and dis-tance between itself and the central node, and determine its position combining the angle and TOA based ranging result. Analysis and experimental results show that the proposed algorithm can provide fine loca-tion accuracy with relative low cost and low complexity.

Biological parameters acquiring devices are very important in Ubiquitous Medical/Health Care system as they are responsible for gathering physical parameters for further analyze. It is natural that they form a wireless network when they transmit the collected data, and the network is referred to as BSN. Energy efficiency is vital in wireless Body Sensor Network (BSN) because the replacement of power resources of the devices implanted in human body is extremely costly. Considering the difference between In-body channel and special channel, a novel BSN transmission scheme, Coop BSN, is proposed in this paper. In Coop BSN, The transmission of Internal Biomedical Devices is divided into two steps as the external devices are used as relays. The first step is the IBD-EEBD transmission, in which IBDs transmit the data they collected with a modified cooperative algorithm. The second step is EEBD-Coordinator transmission, in which multiuser diversity is exploited. With the division of the transmission, the overall transmission energy efficiency is optimized. Theoretical analyze and experimental results showed that, the scheme can prolong the life time of the sensing devices, especially devices implanted in human body in BSN, and can improve the feasibility of BSN.

Biological parameters acquiring devices are very important in Ubiquitous Medical/Health Care system as they are responsible for gathering physical parameters for further analyze. It is natural that they form a wireless network when they transmit the collected data, and the network is referred to as BSN. Energy efficiency is vital in BSN because that the replacement of power resources of the devices implanted in human body is extremely costly. Considering the difference between In-body channel and special channel, a novel BSN transmission scheme, Coop BSN, is proposed in this paper. In Coop BSN, The transmission of IBDs is divided into two steps as the external devices are treated as relays. The first step is the IBD-EEBD transmission, in which IBDs transmit the data they collected with modified cooperative algorithm, DDF. The second step is EEBD-Coordinator transmission, in which multiuser diversity is exploited. With the division of the transmission, the overall transmission energy efficiency is optimized. Theoretical analyze and experimental results showed that, the scheme can prolong the life time of devices, especially devices implanted in human body in BSN, which improve the feasibility of BSN. DOI: http://dx.doi.org/10.11591/telkomnika.v11i12.3722

Proper clustering structure can promote the energy efficiency of Large Scale Wireless Sensor Network (LS-WSN), so as to reduce the cost of using it. Many researches on WSN clustering assume that the nodes in WSN are uniformly distributed, and ignored the position of the sink node. But this assumption differs from practical LS-WSN applications. In this paper, a novel clustering scheme is proposed, which is suitable for the non-uniformly distributed LS-WSNs with mobile sinks. In the proposed scheme, LS-WSN is clustered according to the position aware clustering method, and based on the hexagons virtual grid, and then the cluster structure is adjusted following a game theoretic adjustment process. After the process, the numbers of nodes in all clusters are similar. Theoretical analysis and simulation results showed that, the proposed clustering scheme can balance the number of nodes in clusters, hence prolong the effective lifetime of mobile sink LS-WSN. © 2013 by Binary Information Press.

In the intelligent monitoring of the hypertensive patients, it's necessary to assess their treatment effect and give corresponding diagnostic feedback automatically. This paper proposed a hybrid decision support system (DSS) combining several data mining techniques using an improved weighted majority voting scheme (iWMV). The mass health data of hypertensive patients were used as data source of the data mining techniques, and iWMV was used to produce a proper final judgement on patients' control condition on the basis of the individual classifier results. The proposed system was trained and evaluated using data from 167 hypertensive patients. Performance analysis showed that the hybrid system could reach classification rate (CR) of 95.34% and kappa coefficient (KC) of 92.54%, much better than systems with a single classification algorithm or combining using the simple weighted majority voting scheme (WMV). Moreover, the proposed DSS showed high stability.

To improve the performance of hospital emergency department (ED), we propose a scheduling strategy to reduce the total time of medical tests in ED for a given number of patients. We model the schedulig strategy as a constraint logic programming problem, and then solve this problem with an open source software: Minizinc. Also we compare the medical test time with the scheduling strategy and that without scheduling, which is viewed as a benchmark for our proposed scheduling strategy. The results show that the scheduling strategy can save 12%-25% of medical test time.

Recent advances of hardware and integrated chip have made the body-implanted medical device reality. In this paper, a chronic disease management system with implanted devices based on Wireless Sensor Networks (WSN) was proposed for people with chronic illnesses. We first described the architecture of the chronic disease management system. Then through analyzing the system architecture, we explained the advantages of our new system and pointed out the main issue of the short lifetime of the implanted medical devices. Then a cooperative strategy was proposed in the particular system to decrease the energy consumption, which extended the entire lifetime of all implanted devices. Finally, we evaluated the performance of our strategy with simulations.

In this paper we proposed a novel cochannel interference avoidance strategy for outdoor remote medical monitor network. We employ simulated annealing to design the channel allocation algorithm, which is the core of the strategy. We implemented the strategy in the experimental we built at Beijing outer suburb and took a series of experiments to examine the effect of the strategy. The experimental results showed that the interference level in the network was well controlled after the strategy is used.

In this paper, we propose a novel method to estimate the accuracy of a decision support system for hypertension monitoring. The decision support system is designed building on a diagnosis standard in medicine, and one decision made by this system depends on both the blood pressure data gathered by medical sensors and some contexts that are manually entered by clinicians. When analyzing the system accuracy, we take into account both the potential sensors' errors and the errors of entering context. In addition, we propose a novel method for the estimation of system accuracy; this method is motivated by the fact that the traditional method to estimate system accuracy would overestimate the system accuracy (the details would be presented in Section III.C.). Finally, we compare the system accuracy estimated by the proposed method and that estimated by the traditional method. Our study shows that our proposed method can well estimate the system accuracy.

Cooperative multi-input-multi-output (MIMO) techniques can be used to increase energy-efficiency in Wireless Sensor Networks because of the importance of energy saving for energy-limited nodes. In this paper, we built a new energy consumption model by adding the intra-body channel which has a tremendous path loss into traditional energy model of the Wireless Sensor Networks (WSN). By modeling local transmission channel with intra-body channel mostly studied in Body Area Networks (BAN), we first prove that cooperative MIMO can be adopted to reduce the total energy consumption compared with traditional single-input-single-output (SISO) scheme while transmission distance is larger than a threshold. Furthermore, we proposed a cooperative strategy based on the model from two aspects, the selection principle of the Cooperative Node and the joint optimization of modulation constellation size and Cooperative Node number. By introducing the cooperative strategy into our new energy model, the total energy consumption is tremendously decreased and the threshold is reduced accordingly.

In this paper, we detail the design of a hypertension monitoring system via telecommunication and computer technologies and propose a method for theoretically analyzing its system accuracy. In the design of our system, we add a novel decision support unit, building on a diagnosis standard in medicine, into our monitoring system. The architecture of our system, including this decision support system, is detailed in this paper. In the analysis of our system accuracy, we theoretically evaluate the accuracy of a decision support system by linking the system accuracy with the distribution of sensors' errors. Additionally, we verify our proposed analysis of system accuracy in this paper by comparing its result to that of Monte Carlo simulation.

In this paper, finite element simulative analysis is proceeded for stone-laying overflow dam of Baizhangji secondary hydropower station. Deducing variation law of the dam's stress and displacement in construction process and operational process. The analytic results are shown: stone-Iaying overflow dam of Baizhangji secondary hydropower station is reasonable structure, and every index meets the requirements for design.

This paper adopts finite element method to carry out simulation analysis for Baochuan reinforced concrete rectangular-sectioned beam-supported aqueduct. Deducing variation law of the aqueduct's stress and displacement in construction process and operational process. Analysis results show that, Baochuan reinforced concrete aqueduct structure is reasonable, it meets the requirements for design.

With the unprecedented aging of population, chronic disease become a serious problem in modern medical area. Recent advances of wireless technology make the health monitoring in home to be more convenient for the chronic disease. Reducing the influence of the interference from the other wireless equipment is one of the most important problems in wireless physical parameter monitoring device in healthcare field, as reliable data transmitting is vital in medical care. In this paper, we propose a novel interference avoidance strategy that can greatly reduce the influence of the interference from other wireless equipment to wireless physical parameter monitoring devices in the hospital or home environment. Experimental results show that the strategy has good effect on interference avoidance and reduce the package loss rate.

应用在通信及军事电子等领域的嵌入式系统,由于工作环境和产品的特殊性,对系统的稳定性、可靠性等方面要求非常高,所以需要进行科学、严谨的测试。而由于嵌入式系统的特殊性,对它的测试,尤其是软件测试具有很大难度。本文简要介绍了一种新的嵌入式系统测试方法,TEmb测试方法。通过对该方法的研究,为嵌入式系统的测试工作起到指导和推动作用。

合理的分簇方式能够有效延长大规模无线传感器网络(LS-WSN)的寿命，从而降低其部署使用成本。当前很多WSN分簇的研究均假设节点均匀分布，这与实际应用中的大规模WSN有所差距。该文针对节点非均匀分布的大规模WSN，提出了一种分簇算法。该算法在基于蜂窝结构虚拟网格的位置分簇之后，引入博弈理论设计分簇调整流程，使网络达到各簇中节点数尽量均匀的分簇状态。理论分析和仿真结果证明，通过该方法进行分簇，可以有效均衡各个簇中的节点数，从而延长网络有效寿命。