Distributed spatial analysis in wireless sensor networks

Wireless sensor networks (WSNs) allow us to instrument the physical world in novel ways, providing detailed insight that has not been possible hitherto. Since WSNs provide an interface to the physical world, each sensor node has a location in physical space, thereby enabling us to associate spatial properties with data. Since WSNs can perform periodic sensing tasks, we can also associate temporal markers with data. In the environmental sciences, in particular, WSNs are on the way to becoming an important tool for the modelling of spatially and temporally extended physical phenomena. However, support for high-level and expressive spatial-analytic tasks that can be executed inside WSNs is still incipient. By spatial analysis we mean the ability to explore relationships between spatially-referenced entities (e.g., a vineyard, or a weather front) and to derive representations grounded on such relationships (e.g., the geometrical extent of that part of a vineyard that is covered by mist as the intersection of the geometries that characterize the vineyard and the weather front, respectively). The motivation for this endeavour stems primarily from applications where important decisions hinge on the detection of an event of interest (e.g., the presence, and spatio-temporal progression, of mist over a cultivated field may trigger a particular action) that can be characterized by an event-defining predicate (e.g., humidity greater than 98 and temperature less than 10). At present, in-network spatial analysis in WSN is not catered for by a comprehensive, expressive, well-founded framework. While there has been work on WSN event boundary detection and, in particular, on detecting topological change of WSN-represented spatial entities, this work has tended to be comparatively narrow in scope and aims. The contributions made in this research are constrained to WSNs where every node is tethered to one location in physical space. The research contributions reported here include (a) the definition of a framework for representing geometries; (b) the detailed characterization of an algebra of spatial operators closely inspired, in its scope and structure, by the Schneider-Guting ROSE algebra (i.e., one that is based on a discrete underlying geometry) over the geometries representable by the framework above; (c) distributed in-network algorithms for the operations in the spatial algebra over the representable geometries, thereby enabling (i) new geometries to be derived from induced and asserted ones, and (ii)topological relationships between geometries to be identified; (d) an algorithmic strategy for the evaluation of complex algebraic expressions that is divided into logically-cohesive components; (e) the development of a task processing system that each node is equipped with, thereby with allowing users to evaluate tasks on nodes; and (f) an empirical performance study of the resulting system.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Adaptive and survivable trust management for Internet of Things systems

Abstract The Internet of Things (IoT) is characterized by the seamless integration of heterogeneous devices into information networks to enable collaborative environments, specifically those concerning the collection of data and exchange of information and services. Security and trustworthiness are among the critical requirements for the effective deployment of IoT systems. However, trust management in IoT is extremely challenging due to its open environment, where the quality of information is often unknown because entities may misbehave. A hybrid context‐aware trust and reputation management protocol is presented for fog‐based IoT that addresses adaptivity, survivability, and scalability requirements. Through simulation, the effectiveness of the proposed protocol is demonstrated

Context-aware pending interest table management scheme for NDN-based VANETs

In terms of delivery effectiveness, Vehicular Adhoc NETworks (VANETs) applications have multiple, possibly conflicting, and disparate needs (e.g., latency, reliability, and delivery priorities). Named Data Networking (NDN) has attracted the attention of the research community for effective content retrieval and dissemination in mobile environments such as VANETs. A vehicle in a VANET application is heavily reliant on information about the content, network, and application, which can be obtained from a variety of sources. The information gathered can be used as context to make better decisions. While it is difficult to obtain the necessary context information at the IP network layer, the emergence of NDN is changing the tide. The Pending Information Table (PIT) is an important player in NDN data retrieval. PIT size is the bottleneck due to the limited opportunities provided by current memory technologies. PIT overflow results in service disruptions as new Interest messages cannot be added to PIT. Adaptive, context-aware PIT entry management solutions must be introduced to NDN-based VANETs for effective content dissemination. In this context, our main contribution is a decentralised, context-aware PIT entry management (CPITEM) protocol. The simulation results show that the proposed CPITEM protocol achieves lower Interest Satisfaction Delay and effective PIT utilization based on context when compared to existing PIT entry replacement protocols

Job Stress and its Influence on the Doctor’s Performance in the Public Hospital of Peshawar City, Pakistan

The study aims to find the influence of the job stress on the doctor’s performance in the public hospitals of Peshawar city. No doubt the profession of doctors is very respectable and they are doing a good work serving the people of society but their work environment must have some sort of influence on their performance as well. That’s why this study was taken in to consideration to study the doctors’ performance in the public hospitals. This study was designed to assess the doctor’s performance in public hospitals only. Sample size was drawn on the basis of simple random sampling technique as the data was of quantitative in nature. Data was collected through a questionnaire which was developed by the research himself and to find the reliability and validity a pilot test was done with the data collection tool which showed some mistakes and those mistakes were rectified. Due to limited time period and resources of the researcher, the researcher has drawn 150 sample size of the total population of the doctors in the public hospitals of Peshawar city. A total of 150samples (50 from each public hospitals respectively of Peshawar) data were collected .Out of 150 study participants; it was observed that doctors in KTH, LRH and HMC were suffering from job stress collectively. Their performance was affected and the result of this study highlight the significant result in which it was concluded that job stress had a negative impact on the doctor’s performance in the public hospitals of Peshawar

Burden of Accidents Involving Motorcyclists in District Kohat, Pakistan

OBJECTIVES:The main aim was to assess the frequencies of accidents of motorbike in previous one year and also to estimate the factors related with the accidents.METHODOLOGY:The study design was quantitative and the data was collected from motorcyclists. In order to collect the primary data; a structured questionnaire was used. We interviewed 412 motorcyclists. Almost all the motorcyclist responded and thus we achieved 99% response. Statistical Package for Social Sciences (SPSS) version 21 was used to enter data, clean it and analysis.RESULTS:After the analysis we got hold of some factors, which were associated with accidents. Some of these factors were human, vehicle and environment related factors completing the epidemiological triad of agent, host and environment. CONCLUSION:Based on the results of the study we concluded that bikers must shun the practice of speeding over and above the limits of speed given by the government, one-wheeling, and listening to music while driving. Moreover, the bikers must be taught the basic skills of motorbike riding by authorized personnel and keep latest models of motorbikes, which are in excellent condition. The guardians or parents along with the law enforcement agencies must make ensure that biker must get a license before using the bike. KEYWORDS: District Kohat, Road Traffic Accidents, Burden, Motorbike