The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Shipping information-based management is rapidly developing, which results in increasingly research on location-sensing technologies for shipboard environment. However, these technologies have not been extensively applied on shipboard environment for two fatal limitations. Firstly, they waste resources of node when sometimes fewer nodes are asking for the positioning requirements. Secondly, they ignore...
This article develops a Bayesian belief network model for the prediction of accident consequences in the Tianjin port. The study starts with a statistical analysis of historical accident data of six years from 2008 to 2013. Then a Bayesian belief network is constructed to express the dependencies between the indicator variables and accident consequences. The statistics and expert knowledge are synthesized...
Aimed at ship-board pedestrian positioning, this paper put forward a low-cost positioning method by integrating Pedestrian Dead Reckoning (PDR) and Wireless Sensor Networks (WSN). In this paper, a stable attitude estimator method has been designed through the calibration of IMU's components -- accelerometer, gyroscopes and magnetometers. Apart from this, a pedestrian dead reckoning system has been...
This work considers the problem of decision fusion using the three-level censoring scheme in wireless sensor networks. An optimal fusion rule is derived for the model of Rician fading channel. However, the optimal fusion rule requires instantaneous channel state information (CSI) which may be too costly for resource constrained sensor networks. Hence, a sub-optimal alternative with the knowledge of...
Analysis of open type wharf berthing condition is a complex process. It is hardly to simulate the environment and test results, which are consistent with the actual situation with physical model. In this paper, ship-mooring test during mooring is conducted applying the Large Ship Maneuvering Simulation Platform on the basis of the hydrological, meteorological and underwater terrain data. Combined...
A novel iterative localization algorithm based on Particle Filter with error control is proposed in this paper. First, each node's location is estimated by a cloud of particles and their weights. Second, Degree of Inconsistency(DoI) is proposed to detect the nodes with high error. DoI makes full use of the fact that node density is high and they are randomly and uniformly distributed. The nodes with...
As many interesting and diverse applications of Wireless Sensor Networks(WSNs) are explored, WSNs become an important research field which is rapidly growing due to the development of new technologies in inexpensive sensors. In this paper, a simulation framework is proposed based on OMNeT++ discrete event simulator, and the energy model is discussed for simulating Maritime Surveillance Sensor Networks(MSSNs)...
The location of sensor nodes in wireless sensor networks plays an important role in most applications. In this paper, we address the anchor selection scheme by characterizing some sufficient conditions such that we can offer technical convenience for improving the localization accuracy. Based on the location estimates error analysis of the concentric beacon localization algorithm, 2 or 3 anchors selected...
Wireless sensor n??etworks (WSNs) constitute numerous microsensors that are energy limited. How to design the routing protocol to use energy with high efficiency is one of the most critical issues. In this paper, we propose a distributed singlehop-multihop switch (DSMS) routing protocol for wireless sensor networks. The main idea of DSMS is that the sensor area is divided into several rings of the...
Sensor localization is a necessary and key functionality for the deployment of wireless sensor network (WSN) applications. This paper investigates on the range-free localization approaches for low hardware requirement. A modified DV-Hop localization algorithm is designed to reduce the localization error. The modified DV-Hop uses a novel average hop size estimate scheme, in which the local property...
With the rapid development of e-commerce, security issues are arising from people's attention. The security of the transaction is the core and key issues of the development of e-commerce. This paper about the security issues of e-commerce activities put forward solution strategy from two aspects that are technology and system, so as to improve the environment for the development of E-commerce and...
In this paper, we develop an analytical model for IEEE 802.11 MAC protocol with arbitrary buffer size in unsaturated conditions. The model comprises of a generalized Markov chain model and an M/G/1/K queuing model. We give the thorough and accurate queuing analysis of IEEE 802.11 MAC layer. It's shown that for practical 802.11 WLAN (i.e., buffer size larger than one and number of stations comparatively...
It is very necessary for mobile ad hoc networks to have an efficient routing and quality of service mechanism to support diverse applications. The routing algorithm in the MANETs should also try to balance the network load. Research in this paper combines the multi-constraint QoS mechanism with the load balancing scheme to search the satisfying path between the source node and destination node. The...
In order to support quality of service (QoS) in 802.11 wireless LAN, current research work as well as the enhanced DCF (EDCF) defined in 802.11e standard, tends to provide differentiated services by varying the parameters of MAC protocol. In this paper, we present an analytical model for performance evaluation of these service differentiation schemes in non-saturated traffic conditions. The analytical...
Determining the location of nodes with error as low as possible in wireless sensor networks is an essential task for many applications. It can be shown that, in some case, evident location estimation errors would be brought even if the ranging error is low. This work involves a parameter called geometry favorable factor (GFF) to filter these ill case. We propose an improving method choosing the available...
Numerical simulation of TNT underwater explosion was carried out with AUTODYN software. Influences of artificial viscosity and mesh density on simulation results were discussed. Detonation waves in explosive and shock wave in water during early time of explosion are high frequency waves. Fine meshes (less than 1,mm) in explosive and water nearby, and small linear viscosity coefficients and quadratic...
The location of sensor nodes in wireless sensor networks plays an important role in most applications. In this paper, we address the localization problem by characterizing some sufficient conditions such that technical convenience for the collection of local information used for network localization can be enabled. The main contribution of this paper is as follows. Some latest research results on...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.