Secure multi-level Cluster based wireless sensor network

The demand of wireless sensor networks (WSNs) is on the raise due to its potential applications. The data transmission occurs via a wireless link by the sensor node in network hence these nodes are vulnerable to several outside or inside attacks. A WSN may works in an unfriendly environment therefore it is a fundamental requirement of WSN to secure the sensing data. In this paper, we focus on highlighting the security issues in a multi-layer WSN architecture and provide a secure communication solution (combination of various state- of-art protocols) for it by considering the WSN constraints. We propose a multi-level protocol distribution method to enhance the security of the WSN under consideration via targeting and providing resilience to specific attacks at each level. The simulation and results show that by implementing our proposed method, the overall security of the network has been enhanced

Joint Symbol-Level Precoding and Reflecting Designs for IRS-Enhanced MU-MISO Systems

Intelligent reflecting surfaces (IRSs) have emerged as a revolutionary solution to enhance wireless communications by changing propagation environment in a cost-effective and hardware-efficient fashion. In addition, symbol-level precoding (SLP) has attracted considerable attention recently due to its advantages in converting multiuser interference (MUI) into useful signal energy. Therefore, it is of interest to investigate the employment of IRS in symbol-level precoding systems to exploit MUI in a more effective way by manipulating the multiuser channels. In this article, we focus on joint symbol-level precoding and reflecting designs in IRS-enhanced multiuser multiple-input single-output (MU-MISO) systems. Both power minimization and quality-of-service (QoS) balancing problems are considered. In order to solve the joint optimization problems, we develop an efficient iterative algorithm to decompose them into separate symbol-level precoding and block-level reflecting design problems. An efficient gradient-projection-based algorithm is utilized to design the symbol-level precoding and a Riemannian conjugate gradient (RCG)-based algorithm is employed to solve the reflecting design problem. Simulation results demonstrate the significant performance improvement introduced by the IRS and illustrate the effectiveness of our proposed algorithms

Podcasting to support students using a business simulation

Audio or video podcasts can be a useful tool to supplement practical exercises such as business simulations. In this paper, we discuss a case study in which different types of podcast were utilised to support the delivery of a course in international business. The students work in groups and run a fictional company using business simulation software, which gives them the opportunity to evaluate their decision making skills. A number of podcasts were used as reusable learning objects for different student cohorts. Faculty members produced visually enhanced audio podcasts offered tutor discussions of key elements of the computer-assisted business simulation used by the students. The podcasts were made available via the virtual learning environment (Blackboard Vista), as well as for subscription by web browser-based RSS readers, such as Google and downloadable RSS readers, such as iTunes. Our evaluation of this approach to using podcasts takes into account pedagogic and technical issues. Firstly, faculty members involved in this case study were interviewed to obtain their views and experiences on the process of producing podcasts as well as the suitability of podcasts to support their teaching. Secondly, students were surveyed and interviewed about the value of the podcasts and the way in which they were used. This work is on-going and initial informal student feedback indicates that the podcasts engaged the students and supported their understanding of the international business module. This paper presents a snapshot of the current findings which generally support the value of this innovative way of using podcasting for learning and teaching

Study on QoS support in 802.11e-based multi-hop vehicular wireless ad hoc networks

Multimedia communications over vehicular ad hoc networks (VANET) will play an important role in the future intelligent transport system (ITS). QoS support for VANET therefore becomes an essential problem. In this paper, we first study the QoS performance in multi-hop VANET by using the standard IEEE 802.11e EDCA MAC and our proposed triple-constraint QoS routing protocol, Delay-Reliability-Hop (DeReHQ). In particular, we evaluate the DeReHQ protocol together with EDCA in highway and urban areas. Simulation results show that end-to-end delay performance can sometimes be achieved when both 802.11e EDCA and DeReHQ extended AODV are used. However, further studies on cross-layer optimization for QoS support in multi-hop environment are required

VELOS : a VR platform for ship-evacuation analysis

Virtual Environment for Life On Ships (VELOS) is a multi-user Virtual Reality (VR) system that aims to support designers to assess (early in the design process) passenger and crew activities on a ship for both normal and hectic conditions of operations and to improve ship design accordingly. This article focuses on presenting the novel features of VELOS related to both its VR and evacuation-specific functionalities. These features include: (i) capability of multiple users’ immersion and active participation in the evacuation process, (ii) real-time interactivity and capability for making on-the-fly alterations of environment events and crowd-behavior parameters, (iii) capability of agents and avatars to move continuously on decks, (iv) integrated framework for both the simplified and advanced method of analysis according to the IMO/MSC 1033 Circular, (v) enrichment of the ship geometrical model with a topological model suitable for evacuation analysis, (vi) efficient interfaces for the dynamic specification and handling of the required heterogeneous input data, and (vii) post-processing of the calculated agent trajectories for extracting useful information for the evacuation process. VELOS evacuation functionality is illustrated using three evacuation test cases for a ro–ro passenger ship

Optimisation of Mobile Communication Networks - OMCO NET

The mini conference “Optimisation of Mobile Communication Networks” focuses on advanced methods for search and optimisation applied to wireless communication networks. It is sponsored by Research & Enterprise Fund Southampton Solent University. The conference strives to widen knowledge on advanced search methods capable of optimisation of wireless communications networks. The aim is to provide a forum for exchange of recent knowledge, new ideas and trends in this progressive and challenging area. The conference will popularise new successful approaches on resolving hard tasks such as minimisation of transmit power, cooperative and optimal routing