Advances in Wireless Sensor Networks

With the development of embedded and communication technology, along with the rapid popularization of smart mobile devices in recent years, the communication techniques in ubiquitous networking becomes more and more mature and variety, ranging from wireless communication techniques in long distance such as WiMAX and 3G to wireless communication techniques in moderate distance such as WiFi, as well as wireless communication techniques in short distance such as Bluetooth and ZigBee. Smart mobile devices can take advantages of various communication techniques in ubiquitous networking to connect, discover and communicate to each other, forming into groups to realize cooperation among multiple devices in ubiquitous networking environment. Combined with the application context of cooperation among multiple devices on entertainment in the scene of smart home, ubiquitous networking techniques and smart mobile devices are adopted while a method of group management for multiple devices in ubiquitous networking is put up. And a cooperative platform in ubiquitous networking based on a multi-agent framework, named JADE, is designed and implemented. Last but not least, a prototype system is given to validate the feasibility and the performance.

In cloud storage, the user’s data is no longer locally stored. So the key issue we are facing now is to ensure the reliability and validity of data storage. Due to this problem, erasure codes and token mechanism have been adopted, and then a fault-tolerant method named Ensure Codes token (ECT) has been designed to make sure the correctness of data and rapid position of errors. The result shows that this method can improve the reliability of data storage.

Virtualization is a hot topic in current research. As one of the important applications of cloud computing, the live migration of virtual machine(VM) can move a VM from one host to another without shutting it down. The key of live migration is to reduce the total migration time and its downtime. This paper focuses on the optimization of live migration in Xen environment due to the default algorithm does not work well when memory pages are dirtied rapidly. Base on Xen source code, a DPDT(dirty page delayed transfer) algorithm has been designed. Later experiments show that the improved algorithm reduces the total migration time and downtime efficiently with a high dirtying page rate environment.

mutant information For the internet of things(IoT), how to effectively store heterogeneous data streams is a new challenge. Currently random sampling is generally used for data stream storage. Additionally

B

+ tree is widely used to for quickly indexing. Such data in store are random, and it ignores the users’ interest. In addition,

B+

tree is applicable for one-dimension data, which is not feasible for multiple heterogeneous data streams. Herein, in this paper we propose a new sampling method to satisfy the users’ interest according to the mutant information. Besides that an extended

B

+ tree structure is designed for multiple heterogeneous data stream so that the user can quickly index the interested data. Extensive experiment results show that the new sampling method and the extended

B

+ tree work efficiently than current sampling methods and storage mechanisms.

In this paper, we use a quadrotor-based mobile sink to gather sensor data from the terrestrial wireless sensor network. By analyzing the features of the mobile sink node, we theoretically studied the constraints of trajectory, velocity, height and data amount which the mobile sink can send. According to these analysis results, we propose a data acquisition strategy bases on the trajectory, speed and height of the controlled mobile sink. A plenty of simulations showed that the relationships between the sojourning time, transmission delay, packet loss rate and the mobile trajectory, velocity, etc under this approach, which founded a theoretical basis for such applications.

In order to meet the real-time demand of the intelligent traffic system for traffic information, this paper have presented an intelligent traffic monitoring method based on magnetic sensor, and have analyzed the principles of magnetic sensitive detection and wireless node design, and have developed a practical detection node. Based on experimental test, the success rate vehicle detection is over 95%, and can avoid the iteration count of vehicles. We also have carried out on the speed and length measurement. The results show that the designed node can meet the demand of intelligent transportation system of the vehicle flow, vehicle speed and length parameters real-time monitoring needs. The test results show that the intelligent traffic monitoring method based on magnetic sensor has high accuracy, low cost, easy to deploy, and provides a new practical method and solution for intelligent transportation system.

By analyzing Jin et al’s protocol, we find it doesn’t resist replay attack and man-in-the-middle attack. And then , based on the improvement of the Rabin encryption scheme (SQUASH function), a new lightweight RFID mutual authentication protocol is proposed,which satisfies security requirement: untraceability, denial of service(DoS) resistance, man-in-the-middle attack resistance, replay attack resistance and forward security etc. And the new proposed protocol can support secure ownership transfer between the current tag owner and the new one.

This paper reviews the classic Reachback Firefly Algorithm (RFA) and cites all the problems when applying the RFA to realistic slot synchronization. To make the RFA feasible in slot synchronization, this paper proposed a novel slot modification to overcome the influences from random package arrivals and half-duplex mode. Whats more, a self-developed simulation tool for the RFA in slot synchronization is presented in this paper. Then, based on the simulation tool, simulations are done and impacts from network topologies and network size are thoroughly analyzed. Simulation results show that, considering the same connection rate, mesh topology is the best choice for the RFA in slot synchronization. Moreover, when connection rate stays constant, the performances of the RFA in slot synchronization get worse while the network size increasing.

In this paper, we investigate on the opportunistic routing in Multi-Power Wireless Sensor Networks (MP WSNs). We first propose a routing metric called METT of opportunistic routing in MP WSNs, and model the power selecting process as a Markov decision process for computing the METT metric. We describe the METT-based opportunistic routing problem, and design a polynomial time optimal algorithm for getting the optimal routing and power selection scheme. Theory analysis and experiments show that the proposed multi-power opportunistic routing can improve the data transmission efficiency, significantly reduce the energy consumption and the end-to-end transmission delay.

On the basis of the analysis of the relation between network’s topologyand localization precisionan improved DV-Hop algorithm based on hop correction is put forward. Firstly, RSSI value is used to correct the distance between unknown node and reference nodes in the range of single hop; secondly, a certain amount of correction value is added to the original hop between unknown node and reference nodes to further reduce the distance error between them. Simulation result shows that improved algorithm improves the localization precision.

Opportunistic routing (OR) involves multiple forwarding candidates to relay packets by taking advantage of the broadcast nature and multi-user diversity of the wireless medium. Compared with Traditional Routing (TR), OR can evidently improve the end to end throughput of Wireless Mesh Networks (WMNs). At present, there are many achievements concerning OR in the single radio wireless network. However, the study of OR in multi-radio wireless network stays the beginning stage. In this paper, we focus on OR in multi-radio multi-channel WMNs. Directly using the existing channel assignment leads to decreasing the number of candidate forwarder and the performance of OR. According to OR with one-to-more transmission mode, the Candidate Forwarder Set based Channel Assignment (CFSCA) for OR is proposed. Firstly, according to the candidate forwarder selected by routing, we bound the sender node and its candidate forwarders as a Candidate Forwarder Set(CFS). Then we calculate the interference among all the CFSs. Then the channel assignment for OR is described as a minimum CFS interference optimization problem, which must obey the constraints of the channel number of CFS and the number of radio interfaces. The evaluation results show that CFSCA improves 25.2%, 10%, 19% of the aggregative throughput than random, uniform and tradition channel assignment, respectively.

In range-based localization systems of wireless sensor networks, a small fraction of nodes in the network have known locations while the remaining keep unknown. However, with the change of the anchors distribution, the positioning accuracy of the localization algorithm is quite different. Therefore, we use parameter estimation theory to analyze the node location problem, model the distance measuring with multiplicative normal noise model, and drive the Cramer-Rao lower bound of location. Through simulation we find an effective anchor placement strategy. Compared with random deployment, the proposed strategy provides higher positioning accuracy.

Virtual reality(VR) games have been popular in recent years, developed in the form of the games by capturing the body’s various physiological activities, including the surrounding environmental factors to achieve a colorful variety of game features. This paper presents a system using acceleration sensor to capture the body movements to achieve gaming method. First the user’s motion is captured by accelerometer sensor, then the signals collected by sensor can be processed and sent to computer. Finally the motion data of virtual character are synthesized to the VR game by the common interface processing these data. This motion-imitate system is diversity with combining various other appliances and the price and difficulty of development is reduced comparing with the recent mainstream VR games developing method.

Based on the OGC New Generation SWE-Sensor Web 2.0 and other related projects implementation, this paper gives the four layers architecture of ocean sensor web and details of every layer. The Information Model layer and Interface Model layer are illustrated in detail by the actual example. At last an ocean sensor prototype system sharing data is presented based on the real ocean sensor observing system of 20 nodes wireless sensor network, which is the middleware between ocean sensors and ocean sensor observing data usage. Though the SWE 2.0 standards can be applied in complex scenarios, most of the available deployments are providing data from in-situ sensors.

Cyber-Physical System (CPS) is an important research area which promotes the progress of IT revolution and digital life in the 21st century. As a vital element in CPS, event plays an important role in transforming physical data into our semantic model. Therefore, the event processing scheme is of importance to guarantee the usability of the CPS. In this survey, we at first represent the notion, characteristics and research significance of the events in CPS. Then, we summarize event processing techniques under the context of CPS and its related research fields separately, with pointing out the deficiencies of existing technologies when to support CPS applications. Finally, we discuss the challenges of event processing in CPS as well as its future research directions.

Multi-channel neighbor discovery protocol based on information of detected neighbors for wireless sensor networks is proposed in this paper, called MND. To make sure that the discovery among nodes is as quick as possible, MND uses the schedule mechanism in which the nodes compute the potential neighbors set so as to calculate the sleep and wake schedule of the node. To minimize the influence of channel conflict to the performance, MND uses multi-channel mechanism and calculates the required total number of channels according to the duty cycle and network density. Through analysis, we can get how to choose the total number of channels for each node and the fact that the common neighbor node of the neighbors of a node is the neighbor of this node in a large probability. The simulation and test-bed experiment results show the discovery rate and discovery latency of MND is higher and lower, respectively.

According to the significant impact on the accuracy rate of detection of current immune algorithms brought by incorrect classification of signal, it proposes network malicious code dendritic cell immune algorithm based on fuzzy weighted support vector machine. It summarizes and compares the pros and cons of the four methods, which are basic artificial intelligence immune algorithm, detection of unknown viruses based on immunity theory, malicious code immunity based on cryptography and automated intrusion response based on danger theory. It elaborates the process of the algorithm of the proposed immune algorithm, discusses a variety of input and output signals, gives the samples of the actual input signals, applies the coefficient of variation method to determine the values of the weights so as to enhance the discrimination ability of signal processing results, describes the principle and algorithm steps of fuzzy weighted support vector machine clustering method within immune algorithm proposed. By comparing the fuzzy aggregation before and after the immunization program experiments, it draws the conclusion that the proposed immune algorithm can optimize the input signal, fuzzy clustering the signal and the antigen, so as to bring down the number of immunization strategies and reduce the immune response time, as a result it improve the efficiency and performance of the immune system.

Flying a swarm of unmanned aerial vehicles (UAVs) with mutual sense and communication capability in the air space, a late-model airborne perceptive network accordingly takes shape. Among all research issues about it, routing strategy is the prior problem that significantly blocks the whole efficacious communication, because this three-dimensional architecture features randomly violent topological changes and usable paths generate in an unpredictable moment. In this paper, we consider an exploration-exploitation trade-off in this specific delay tolerant network (DTN). The pivotal conception is the resultant of heuristic information and ant pheromone based on the ant foraging behavior. A fuzzy inference system is introduced to calculate the heuristic information using approximate reasoning, which helps ant routing. The simulation witnesses the effectiveness of the proposed mechanism in the end.

With the scientific and technological progress, new-style three-dimensional (3D) mobile sensor networks draw the attention of many exciting applications in multifarious areas, where the former two-dimensional (2D) assumptions do not make sense. Existing references were mostly restricted to 3D static sensor networks, featuring either random or deterministic, while basing on more realistic mobile conditions, the studies were rarely referred. In this paper, we, for the first time, apply the noted virtual force algorithm (VFA) to 3D space. Except for traditional virtual forces, central gravitation and equilibrium force are additionally introduced to get better sensor distribution. Then four groups of cases are presented to summarize various mobility patterns and two metrics are of particular interest to evaluate the performance of our proposed improvement, namely coverage ratio and homogeneous degree. The simulation witnesses the effectiveness of the improved mechanism in the end.

This paper makes an introduction to a module harvesting wind and solar, it is designed for wireless sensor node to meet the need of power in outdoor application like forest monitoring. To get very long life, the module harvests wind and solar together, takes the super capacitor and alternate lithium battery as the energy store device to take advantage of their complementary nature. A wind MPPT (maximum power point tracking) circuit which is specifically designed for application in wireless sensor network and a solar tracking circuit are designed to increase the efficiency of energy harvesting.

Tracking initiation issue under bearing-only sensor networks is studied. A mechanism for tracking initiation based on probability is proposed, aiming at solving problem under measuring environment with false alarm and undetected. The mechanism is achieved by two phases including target localization and target confirm. In target localization phase, Multiple Target Probability Localization algorithm is proposed to estimate target initial state, providing new thinking for multi-target localization under bearing-only measurements which distinguishes the true target localizations from the false ones relatively by probability. In target confirm phase, target probability is introduced as judgment for tracking initiation and a recursive algorithm under multi-sensor is provided. The simulation shows that the proposed mechanism can be well-work under different settings and the required computation is limited which is suitable for WSN.

A Graph-based multi-hop cooperative MIMO transmission scheme (GM-MIMO) aimed at optimizing the network lifetime and saving energy for heterogeneous wireless sensor networks (WSN) is proposed. In GM-MIMO, clusters are established based on geographical position. Graph theory is applied to find an optimal forwarding path. For taking the presence of node heterogeneity into consideration, GM-MIMO obtains maximum network lifetime. Simulation results show that GM-MIMO makes a significant performance improvement in terms of network lifetime and survival rate of nodes.

WIA-PA (Wireless Networks for Industrial Automation - Process Automation) is IEC international standard. In order to solve the primary problem of wireless network in industrial applications, i.e. anti-jamming problem, WIA-PA support adaptive hopping technology. Two adaptive hopping methods based on WIA-PA standard are proposed in this paper. The proposed methods is realized and evaluated based on the experimental platform, the result indicates the feasibility and availability of the proposed methods.

Despite recent improvements of the capabilities of wireless sensors, network protocol support for key exchange is still lagging behind. Three-party password-based authenticated key exchange protocols allow sensors communicate over an open network securely using high entropy session keys originated from a low entropy password. Due to their convenience in building a secure communication channel, many password-based key exchange protocols have been proposed and investigated over the years. Nevertheless, protocol must be designed carefully so as not to be broken using dictionary attacks in which an adversary tries all possible passwords in an attempt to figure out the correct one. Besides, protocol must be environment-friendly. That is say, the protocol should not pose too much loads on wireless sensors. And hence, a novel 3PAKE protocol is proposed for wireless sensor networks, which has better performance compared with similar protocols.

Underwater sensor networks will find many underwater applications in near future, and the topology formation problem in 3D sensor networks has not been paid enough attention at present. In order to maximize the network lifetime and shorten the propagation delay, a topology formation algorithm (TFA) for underwater sensor networks is proposed. TFA is based on a scale-free network approach (GLP model), and the generated topology has minor average path length and clustering coefficient, where node degree follows power law distribution as well. The simulation results suggest TFA can extend the UWSN lifetime and shorten propagation delay effectively.

The full-view coverage ensures that the positive images of targets are obtained. In existing works, the topics only focus on whether a region is full-view covered or not, which needs too many nodes, and is less flexible for the change of surveillance environment. Therefore, full-view coverage for the targets is highlighted in this paper. Firstly, we derive the optimal observation angle between the sensing direction of nodes and the vector of target surface. We also prove that the full-view coverage is a NPC problem. Then the centralized and the distributed algorithms are proposed to maximize the number of full-view covered targets by scheduling the sensing directions of some sensors in the network. Simulation results show that local adjusting of the directional nodes will increase the full-view coverage for the global monitored objects in the condition of random deployment.

The traffic information collection system is the underlying part of the intelligent transportation system. In this paper, we propose a novel real-time traffic information collection system, which recognizes driving status, detects the driving route, and updates the traffic condition accordingly. Specifically, we first model the roads as a virtual map, and then based on which we design a lightweight road topology relational database. Secondly, taking advantage of accelerometer and compass on the smartphone, we propose a lightweight driving status tracking algorithm that can accurately recognize users driving status. Finally the sensors readings is considered along with users driving status and the database to give real-time automatically route recognition. Meanwhile, in order to get accurate real-time information as well as protect users privacy, users driving speed is calculated in real-time manner and the encrypted driving route results are uploaded to the server. Experiments results show the effectiveness of our system.

The design of wireless sensor networks for signal detection applications has to consider the limited battery power of the sensor nodes. Considering the scenario of using distributed radar-like sensors to detect the presence of an object through active sensing, we formulate the problem of power allocation between sensing and communication for signal detection under the Neyman-Pearson criterion. An allocation scheme of node’s power budget between sensing and communication is presented. The objective is to maximize the global probability of detection under a fixed node’s power constraint and a given global probability of false alarm. Simulation results show that the proposed method leads to a big gain in performance.

With the rapid development of Internet of Things (IoT), vast amounts of heterogeneous resources have been connected to the network. How to effectively manage these resources will become a critical issue. This paper first summarizes the current status of the resource management in different scenarios, like WSN, RFID, and RSN. Then from a user perspective, based on the resource name service, we propose a generic resource management model, which is composed of users, devices and resources. Two actual cases are introduced to describe how users can obtain the logical information and control the entity object through this theoretical model. Finally, the analysis shows that this model can meet the needs of ordinary users in compatibility, stability, real-time and flexibility for IoT resources management.

In clustered wireless sensor networks, to reduce the energy consumption and improve utility of network, it is proposed that cluster head is endowed with higher priority and a novel joint optimal model of power and rate is given. The distributed iterative algorithm is achieved by choosing the appropriate utility function, which is suit for variable separation and distributed computing. The dual decomposition method is adopted in the algorithm. Simulation results show that the joint optimal algorithm can prolong the lifetime of network and improve the comprehensive efficiency effectively.

Recently, the sweep coverage has attracted much attention from researchers. There have been some works on the sweep coverage. However, none of them takes into account some constraints of real environment. In this paper, we study the minimum

t-Sweep Coverage with Mobile Sensors on Two-way Road (SCMMSTR)

problem, which is how to schedule mobile sensors’ movement to satisfy the requirement of

t

-sweep coverage under the constraints of two-way roads such that the number of used mobile sensors is minimized. We first study the

Minimum Directed Cycles Set (MDCS)

problem to find a set of directed cycles which contains all vertexes such that the total length of these cycles is minimized. A greedy algorithm-

Finding Directed Cycles Set (FDCS) algorithm

is proposed for the

MDCS

problem. Secondly, we study the

Scheduling Mobile Sensors (SMS)

problem which is to schedule mobile sensors along a given set of circles such that the number of required mobile sensors is minimized. We propose the

Scheduling Mobile Sensors

(

SMS

) algorithm for the

SMS

problem. Based on the

FDCS

algorithm and the

SMS

algorithm, we propose the Computing Minimum Directed Cycle algorithm for the

SCMMSTR

problem. Simulation results demonstrate the performance of our algorithms.

This paper proposes a Hybrid Mac protocol(H-MAC) that combines reservation and competition mechanisms to solve the sudden burst data flow at link layer of the VANET(Vehicle Ad hoc Network). Based on the entire network time synchronization, H-MAC protocol divides a frame cycle into two parts. The first part is reservation period in which each node has its own slot. Node could send stable data flow such as beacon packets in the slot. The second part is competition period in which burst data could be sent. Therefore, beacon frames and burst data are divided. H-MAC improves the utilization of channels and reduces delays that caused by collision of the burst data. Simulation results show that the proposed H-MAC protocol provides high reliability of broadcast data at MAC layer.

Currently, few studies of wireless sensor network node localization algorithm were focused on the reference nodes, but how to choose and place reference nodes has a great influence on the positioning accuracy. In order to quantitatively study this issue, we proved a theorem, which describes the relationship between the placement of reference nodes and whether the node can be located, then the reference nodes placement method was designed. Finally, a reference nodes selection algorithm was proposed based on the condition number of linear equations, so as to improve the accuracy of range-based localization algorithm.

Multi-channel MAC protocols have recently attracted much attention as it is considered a promising direction for improving the performance of wireless sensor networks. But most of these protocols didnt consider the performance of broadcast. The traditional broadcast is difficult to work in multi-channel wireless sensor networks using dynamic channel assignment. In this letter, we proposed a distributed solution to broadcast by multiple unicast based on a broadcast tree. The tree can be built through sending broadcast training packages several times before broadcast. The simulation results showed that this broadcast protocol has good broadcast latency metric.

This paper presents an Mobile Agent based Coding Aware Routing (MA-CAMR) for wireless sensor network, which exploits mobile agent to discovery the routing and coding opportunities, reducing complexity of node design. Besides, the general network coding condition of two cross flows is proposed for coding opportunity discovery. In addition, a novel routing metric, Coding and Energy Aware Routing Metric (CEARM) is proposed, which considers the coding gain, the load and energy of node. MA-CAMR exploits multipath routing and CEARM to balance the network load and energy consumption. Simulation results demonstrate that MA-CAMR could balance network load and energy consumption, reduce energy consumption, and prolong network lifetime.

Energy saving is a key issue for prolonging the runtime of Wireless Sensor Network (WSN). In real-time applications of WSN, it is required to deliver data to the sink within a delay constraint. It is significant to design a scheme that maximizes the lifetime of WSN and satisfies delay constraint. To meet this requirement, in this paper, we present the Maximizing Lifetime and Delay Aware Scheme (MLDAS) that uses genetic algorithm, in which stochastic ranking (SR) method is applied, to find an Energy and Delay Aware Tree (EDAT) used to gather data in the WSN. Simulation results show that the MLDAS outperforms some existing schemes in terms of network lifetime and data accuracy.

Time synchronization is an important supporting technology for wireless sensor network (WSN). In most existing WSN time synchronization algorithms, timestamp is recorded by software when sending and receiving synchronization messages, which involving synchronization errors like send time and access time. In this paper, a WSN time synchronization algorithm based on SFD is proposed. In the novel algorithm, timestamp of synchronization message is recorded by SFD hardware capture. It can effectively eliminate send time, access time and other synchronization errors. Experiments based on proposed algorithm have been done to verify the effectiveness and time synchronization errors are analyzed.

In order to coexist Bluetooth with Wi-Fi in mutual interference environment, carrier sensing and traffic forecasting model are used to optimize the packet selection mechanism in Bluetooth frequency-hopping process. The probability of collisions of Bluetooth signal and Wi-Fi signal is gained by baseband layer energy sampling and Wi-Fi traffic forecasting model. According to the collision probability, the packet types are selected to achieve maximum throughput of Bluetooth. Simulation and analysis show that the algorithm can effectively coexist Wi-Fi with Bluetooth by mean of time divided channel multiplexing in real world Wi-Fi environment.

Due to the nature of many-to-one or many-to-few traffic patterns in Wireless Sensor Networks (WSNs), some critical nodes overloaded will exhaust their energy fast and will cause the decrease of the network lifetime for WSNs. Typically, routing protocols employ a reliable routing cost metric to avoid the lossy links but cannot balance the energy consumption of different nodes in WSNs. In this paper, we present an energy-aware routing algorithm to maximize the network lifetime of WSNs with the introduction of a new routing cost metric, whose goal is to achieve the best trade-off between energy consumption and routing link selection. We evaluate the performance of our routing algorithm by comparing it with other accessible routing algorithms. And the simulation results show that this energy-aware routing algorithm performs better in network lifetime as well as reliability.

This paper makes a briefly introduction to the background and status of the wireless sensor network and the android platform. It designs and implements the system manager based on android platform for WIA-PA wireless sensor network with combined the advantages of the two techniques, which can provide a real-time, low-cost management manner for wireless sensor network.

IOT will effectively promote the development of Chinese light industry. In this paper, we firstly introduce the technical architecture of Chinese light industry IOT. Then we analyze the key technologies of it, including the Cloud-Channel-Terminal technology system, identification technology, NFC terminal solutions and architecture technology. We also introduce the key R & D direction of the application of Chinese light industry IOT in the paper. The research in the paper will be helpful for comprehensively promoting the transformation process of Chinese light industry IOT application.

DTN is developed as an emerging network technology which is mainly used in network with long waiting time, intermittent connectivity, and other extreme environments network. It has be favored in the military, transportation, marine monitoring, wildlife tracking, satellites communications and have been applied in some aspects. Currently, there is a lot of research about the DTN. The study includes three hot issues: the routing nodes, DTN-based mobility model and the data distribution and retrieval. To better solve the problem of data distribution and retrieval in DTN, an improved routing algorithm is proposed in this paper.

Privacy of RFID systems is receiving increasing attentions in the RFID community and an important issue required as to the security of RFID system. Backward privacy means the adversary can not trace the tag later even if he reveals the internal states of the tag sometimes before. In this paper, we analyze two recently proposed RFID authentication schemes: Randomized GPS and Randomized Hashed GPS scheme. We show both of them can not provide backward privacy in Juels and Weis privacy model, which allows the adversary to know whether the reader authenticates the tag successfully or not. In addition, we present a new protocol, called Challenge-Hiding GPS, based on the Schnorr identification scheme. The challenge is hidden from the eavesdropping through the technique of Diffie-Hellman key agreement protocol. The new protocol can satisfy backward privacy, and it has less communication overheads and almost the same computation, compared with the two schemes analyzed.

In recent years, several new TCP congestion control algorithms have been proposed to improve TCP performance for networks of high bandwidth delay products. Satellite-HAP networks providing high-speed data transmissions (up to 1 Gb/s). This article aims to show that the proposed new TCP, as a modification of TCPs congestion control mechanism, allows it to achieve reasonable performance in Satellite-HAP networks. In this paper, we implement the performance simulation in NS-2, and the results demonstrate that the proposed new TCP for Satellite-HAP networks has a considerable performance improvement comparing with the other variations of TCP.

In order to solve the problem of the credibility on Web educational resources under the current cloud computing platform, we propose a hierarchical pre-selection model of Web educational resources based on trust mechanism. Firstly, a credibility assessment of the Web educational resources was presented. Then the level on pre-selection model by credibility was established. Finally, the resource routing algorithm based on hierarchical pre-selection model was proposed. Simulation results show HPBTA model could ensure that cloud computing Web education resource is availability. In addition, the model provides a solution to pre-selection of cloud computing Web education resources.

To implement the objective of smart traffic system, it is essential to introduce the cutting-edge Information technology, and applied to the transport system. Cyber-physical system (CPS) is a highly complex system that deeply integrates the physical and computing process. Its core is the organic integration of computing, communications and control technology to achieve real-time monitoring, analysis and control of large-scale interconnected physical systems. CPS has broad application prospects. In this paper, the basic framework of the Cyber-Physical traffic System (CPTS) is proposed. The concept and relevant characteristics of the CPS are first introduced. The architecture and key technology of CPTS are then illustrated. Next, Research techniques and methods of future CPTS are discussed in details, from the aspects of system modeling, large-scale information acquisition, optimization and control. The major challenges of CPLS research are finally discussed in details. Finally the future development path of CPTS is simply analyzed.

Energy efficiency is a key issue in wireless sensor networks. Researches on the energy efficiency evaluation models could promote the development and application of WSN. In this paper, wireless sensor network was modeled as a mechanical work system whose work-efficiency was defined as the metric to measure energy efficiency. In addition, our model introduced a power aggregation function and utility function to filter out application-specific features. Then, based on these models and metrics, we proposed a general framework to evaluate energy efficiency and applied relative energy consumption to measure the operational cost of heterogeneous nodes. Furthermore, we constructed two metrics, average energy discharge rate and energy entropy, to quantitatively measure a systems energy consumption status. The effectiveness of our evaluation model and metrics had been validated by the simulation results.

This article reports an Energy Efficiency Dynamic Routing Protocol for Farmland Moisture Sensor Networks (EEDRP-FMSN) to improve energy efficiency, which combined the characteristics of farmland wireless sensor network deployment model. The EEDRP-FMSN protocol made use of the characteristics that the position of the base station was fixed, and the next hop selection mechanism of the EEDRP-FMSN protocol considered communication quality among nodes, global routing information, residual energy of nodes, and so on. The next hop selection mechanism had the dynamic nature and stronger environmental adaptability to extend the life cycle of network. The EEDRP-FMSN protocol overcomes the shortcoming that capacity and bandwidth of the routing table correspondingly increased with more nodes joining the network. This article also simulated the performance of the EEDRP-FMSN protocol in different conditions and evaluated the performance from energy efficiency, packet energy consumption and packet distribution balance by comparing the EEDRP-FMSN protocol with DSDV, EAP protocols. Simulations indicated that the EEDRP-FMSN had more energy efficiency than the EAP and the DSDV. The EEDRP-FMSN protocol overcame the shortcomings, such as capacity and bandwidth of the routing table increased with more nodes joining the network. It had better scalability, and keeps network loading balance.

The passive object localization problem (POLP) aims to detect the location of the target. This task requires the target does not have any device to receive signal or transfer. For this reason, the data type used for the passive object localization is limited in WSN. The great challenge is how to use rare data to estimate the location in the large area. In this paper, based on our preliminary work, we propose a novel approach to localize objects which is referred as SLAL(Sensing Link Adaptive Localization) in which we can judge the location attribute by the adaption rule, calculate the target position by the diffraction model and point out the area by the RSSI affected. Compared with the traditional methods, our major contribution is that study the diffraction model and the affected degree of RSSI, ensure the localization accuracy with the link length extending. Experimental results demonstrate that the localization accuracy of SLAL outperforms previous methods. Laid the foundation for improve the accuracy in further.

The solution of extended Chinese remainder theorem(ECRT) based radio interferometric ranging (RIR) is in closed form, thus the computational complexity is greatly reduced compared with previous methods. Therefore, ECRT-based RIR shows us the prospects of employing RIR for distributed localization in Wireless Sensor Networks (WSN). But ECRT-based RIR have a tight constraint on the measured frequencies. In this paper, relations between the probabilities of normal error, frequencies available, maximum unambiguous range, the greatest common divisor

C

and phase noise are given. Then an optimal frequency selection method with computational complexity of

O

(

N

!) and a suboptimal frequency selection method with computational complexity of

O

(

N

2

) are presented. We can effectively have a tradeoff between noise tolerance, number of frequency available and the maximum unambiguous range in system design. Simulation results corroborate the effectiveness of proposed methods.

The corresponding author of this paper is Weijun Qin. This information was inadvertently omitted from the original publication.

Link scheduling is one of the main difficulties for a large amount of data real-time and reliable transmission in Wireless Multimedia Sensor Networks. To improve multi-hop transmission performance, MAC layer link scheduling algorithms have received extensive attention. These algorithm allocated slots for every data link. It could lower the number of conflicts and retransmissions. However, as the network size increases, both centralized or distributed scheduling algorithms encounter performance degradation problems. To overcome this problem, a novel scheduling algorithm which based on network partition was proposed. In sparse region, the MAC layer switches to a simple 802.11 mode; In intensive region, the MAC layer switches to queue length based scheduling mode. Emulation study showed that the proposed algorithm had a better performance in both terms of total queue length and average delay.

The node for building of wireless sensor network to monitor the moisture of urban green space based on the Modular design ideas was designed and implemented. Node is connected together by three separate boards, wireless transceiver, microprocessor and sensor backplane. In order to monitor the vertical distribution of the soil moisture, the sensor base plate is designed that it can access the 8-channel soil moisture sensor at the same time. The node has a time-sharing function. The test results show that the average current is 0.256 mA with the collection frequency of 30 seconds, it is 10 uA in sleeping mode. It can save power consumption than similar products by about 30.

In order to reduce network energy consumption and prolong the lifetime of wireless sensor networks, this paper improves the LEACH to an energy efficient multi-hop routing algorithm. LEACH in the cluster creation, data transmission, the update phase of the cluster was modified in proposed algorithm. The algorithm updates the cluster head reasonably and adjusts the structure of the cluster to reduce the energy consumption in cluster establishment phrase. In data transmission, it lowers energy consumption by inter-cluster and intra-cluster multi-hop transmission. The simulation runs the algorithm on NS2. The results show that the new algorithm’s effectiveness in reducing energy consumption by comparing it with LEACH, LEACH-C,DEEUC.

The connectivity is one of the key issues in the design and application of wireless sensor networks, which is a basic guarantee for the normal operations of networks. In this paper, the region regularity is introduced into the wireless sensor network model for connectivity analysis. By analyzing and simulating the link probability, the average node degree and the node density of networks, we summarize the influence of region regularities on network connectivity. Experimental results show that the connectivity varies with different region regularities and reduces with the decrease of region regularity. Moreover, the energy efficiency and lifetime of the sensor networks can be improved by the analysis of region regularity. To the networks in two-dimensional plane, the proposed methods can also be applied.

The effective use of sensor node battery is crucial for wireless sensor networks (WSNs). Based on a realistic power consumption model for wireless communications, we consider in this paper the low-power-consumption design for multi-hop routing in WSNs. To this end, we first mathematically study the dependence of communication power consumption of a multi-hop route on the relay node placement. Theoretical derivation reveals that in order to minimize the communication power consumption, the relay nodes should be uniformly placed along the line segment connecting the route ends. Utilizing these results, we then proceed to perform a numerical analysis on the relationship between communication power consumption and the number of relay nodes in the route. It is found that the optimum number of relay nodes is almost linearly proportional to the route length from the source node to the sink node. Computer simulations corroborate the theoretical results.

The routing optimized problem in HAPs-Satellite integrated network is focused on this paper. A novel routing algorithm(AR-HS) based on the swarm intelligence by changing the pheromone updating strategy is proposed. In order to build an optimal solution, the proposed algorithm make use of ant agents that consist of probe packets sent on the HAPs-Satellite integrated network that allow to find the optimization problem solution. In this work we have performed a comparison of a classical shortest path algorithm with our the proposed algorithm ,and the simulation results show that our routing algorithm can reduce end to end delay and drop ratio, and improve performance of network.

Wireless communication system plays a more and more important role in many fields. Wireless network using traditional AODV algorithm only considers the minimal hop of all routes and can not meet specific QoS requirements. Some network resources will be wasted to some extend using traditional algorithm. A cognitive routing algorithm, R-AODV, which is based on the AODV algorithm, is proposed in this paper. The new proposed algorithm collects network status and chooses different routing strategy to make the best use of network resources. It may collect network status before having routing algorithm and according to different conditions of current network to choose different routing algorithm, which may make the best use of network resources.

As a necessary complement to static identity authentication mechanisms in secure applications of ad hoc network, node behavior trust evaluation can solve many security problems effectively. This paper has a general overview on node behavior trust evaluation, analyzes issues of trust model, behavior monitoring, evaluation metrics, trust computation etc., which provides a reference on the future research.

Combining wireless sensor network and array signal processing technology, a novel array-forming wireless sensor network framework is presented. Sensor nodes, connected through wireless communication, are grouped to form virtual arrays. Then high-accuracy target positioning can be performed with the help of array signal processing algorithms. Considering real-time target monitoring applications, system performance is modeled in aspects of accuracy, delay and power consumption. To satisfy system performance requirements with inherent contradiction among them, system objective function is built and optimized scheduling is obtained with optimization algorithm. Simulation results verified our performance model and the feasibility of array-forming wireless sensor network framework, and also provide suboptimal solutions for scheduling.

Due to the contradiction between overwhelming traffic and limited bandwidth, congestion is one of the most challenges in wireless sensor networks (WSNs). In this paper, based on network coding and cross-layer optimization, we propose a reliable transmission control scheme to avoid congestion. Our scheme uses network coding to improve the reliability and robustness of system, and applies cross-layer design for suitable rate assignment. Our simulation results and analysis show that our scheme can achieve good performance in terms of reliability and throughput.

Cooperative communication can send and receive message with virtual MIMO antenna arrays stemming from sharing other users antenna in the network, leading to reducing energy consumption. Cooperative routing is a cross layer routing by using the technology of Cooperative communication in physical layer and routing selection in network layer. For the purpose of maximizing the network lifetime, this paper proposes a weighted power allocation with cooperative transmission by considering various elements, including initial energy of nodes, residual energy, transmission overhead, and designs a cooperative routing algorithm for maximizing network lifetime (MNLCR) which is based on that weighted power allocation. The simulation results show that MNLCR can extend 25% of the network lifetime compared with FACR.

abstract

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In order to find the service nodes, which the users are satisfied with, in a high speed and efficiency in open network environment, a new grid-oriented multi-level service selection model is proposed, which is based on the concept of user-similarity group. On this condition, direct trust calculation based on time decay is given and fine-grained recommendation trust calculation is studied, which can distinguish the ability of honesty. In addition, based on activity level of nodes, dynamic weight-allocation method is proposed, which can make the prediction results be closer to the fact. After job-interaction, the update algorithm about honesty ability of recommendation nodes is researched, which will provide more reasonable and reliable reference for the next prediction. Simulation results show that the service selection model and trust calculation methods are reasonable and accurate.

Optical human motion capture system can be applied in commercial use, but require expensive studio-like environments which cannot be fulfilled for daily-life use. We present a substitute system: a real-time motion capture system based on micro sensors, which is ubiquity, low-cost and able to reconstruct human motion almost in any environment in real-time. This system consists of three subsystems: a sensor subsystem, a data fusion subsystem and an animation subsystem. Experiments show that our system can reconstruct motions and render animations in real-time, and reach the accuracy of optical human motion capture system

Data prediction has been emerged as an important way to reduce the number of transmissions in wireless sensor networks(WSNs). This paper proposes a periodic data prediction algorithm called P-DPA in WSNs. The P-DPA takes the potential law hidden in periodicity as a reference to adjust the data prediction, which helps to improve the accuracy of prediction algorithm. The experiments of temperature, humidity and light intensity based on the dataset which comes from the actual data collected from 54 sensors deployed in the Intel Berkeley Research lab proved that the P-DPA has an obvious enhancement to the existing data prediction algorithms.

The wireless networks based on the IEEE 802.15.4a CSS (chirp-spread-spectrum) PHY are expected to provide accurate ranging. However, the problem is that the measured distances are not only noisy but also biased, which becomes more serious in non-line-of-sight situation. To improve the accuracy of ranging, two methods are used to estimate the positive bias, including state augmentation technique and separate-bias estimation. Then the bias estimation can be used to correct the measured distance. Experiments conducted with Nanotron CSS wireless nodes in indoor-environment validate the algorithm actually. The effectiveness and features of the filtering algorithms are analyzed with the support of the experiment results.

The security problem of beacon nodes is ignored in most existing localization algorithms in Wireless Sensor Networks (WSNs), although beacon nodes’ location information is crucial to the process of sensor nodes’ localization. Assumed that some of beacon nodes were attacked as a result of the secure vulnerability of WSNs, a secure DV-Hop localization algorithm based on beacons’ credits is proposed in the paper. By distributed calculating the credits of beacon nodes, sensor nodes could eliminate the malicious beacon information effectively according to their credits to ensure the correctness of beacon location information they received. Finally, the efficiency and feasibility of proposed algorithm are proved by the performance evaluation results.

The proliferation of wireless and mobile network has fostered the demand of context aware applications. Location is one of the most basic and significant contexts. An improved DV-HOP localization algorithm based on connectivity of network is proposed in order to decrease the hardware cost and implement in complexity WSN. First of all, by using the weighted least-mean-square error criterion to estimate the network average single hop distance, we can obtain the distance information between any interconnected nodes. Then, the geometric position of the reference nodes affects the localization accuracy; we propose a selective strategy of reference nodes involved in the position calculation process. Finally, based on trusted links to get the location information. The simulation results show that compared with the DV-HOP localization algorithm, the positioning accuracy is improved, and also improves localization performances.

The 6LoWPAN protocol is used in delivering IPv6 packet over IEEE 802.15.4 based wireless sensor networks (WSNs). In 6LoWPAN, adaptation layer is introduced in the protocol stack so that routing can be performed either in the adaptation layer, called mesh-under routing (MUR), or in the network layer, called route-over routing (ROR). To deliver an IPv6 packet over a WSN, the packet has to be divided into multiple fragments, with each being carried in an IEEE 802.15.4 frame, due to the small payload of an 802.15.4 frame. Thus, MUR exhibits the drawback of low packet arrival rate (PAR) when delivering an IPv6 packet over a route consisting of multiple unreliable links in the WSN because the destination node cannot assemble the original IPv6 packet if any fragment of the packet is lost over any link. This drawback is remedied by the proposed chained MUR (C-MUR) scheme, in which some intermediate nodes between the source and the destination are chosen as temporary assembling nodes (TANs), where the received fragments are assembled into the original IP packet and the assembled packet is fragmented again and delivered to the next TAN or the destination node. Experiments show that C-MUR outperforms both MUR and ROR in terms of PAR.

Wireless senor networks have more and more applications while fundamental constraint still exists, such as limited power supply and bandwidth. When the sensing signal exhibits spare, we can sampling only a part of signal corresponding to nonzero coefficients. Inspired by recent results in theory of compressive sensing (CS), we propose a data fusion method based on CS. First, we describe the distributed data fusion in UWSNs based on CS. Then, we present a monitoring model of the cyanobacteria bloom-forming (CBF). Finally, we demonstrate the performance analysis and provide concluding remarks.

The corresponding author of this paper is Weijun Qin. This information was inadvertently omitted from the original publication.

The corresponding author of this paper is Weijun Qin. This information was inadvertently omitted from the original publication.