1,630 research outputs found

    Cognitive Security Framework For Heterogeneous Sensor Network Using Swarm Intelligence

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    Rapid development of sensor technology has led to applications ranging from academic to military in a short time span. These tiny sensors are deployed in environments where security for data or hardware cannot be guaranteed. Due to resource constraints, traditional security schemes cannot be directly applied. Unfortunately, due to minimal or no communication security schemes, the data, link and the sensor node can be easily tampered by intruder attacks. This dissertation presents a security framework applied to a sensor network that can be managed by a cohesive sensor manager. A simple framework that can support security based on situation assessment is best suited for chaotic and harsh environments. The objective of this research is designing an evolutionary algorithm with controllable parameters to solve existing and new security threats in a heterogeneous communication network. An in-depth analysis of the different threats and the security measures applied considering the resource constrained network is explored. Any framework works best, if the correlated or orthogonal performance parameters are carefully considered based on system goals and functions. Hence, a trade-off between the different performance parameters based on weights from partially ordered sets is applied to satisfy application specific requirements and security measures. The proposed novel framework controls heterogeneous sensor network requirements,and balance the resources optimally and efficiently while communicating securely using a multi-objection function. In addition, the framework can measure the affect of single or combined denial of service attacks and also predict new attacks under both cooperative and non-cooperative sensor nodes. The cognitive intuition of the framework is evaluated under different simulated real time scenarios such as Health-care monitoring, Emergency Responder, VANET, Biometric security access system, and Battlefield monitoring. The proposed three-tiered Cognitive Security Framework is capable of performing situation assessment and performs the appropriate security measures to maintain reliability and security of the system. The first tier of the proposed framework, a crosslayer cognitive security protocol defends the communication link between nodes during denial-of-Service attacks by re-routing data through secure nodes. The cognitive nature of the protocol balances resources and security making optimal decisions to obtain reachable and reliable solutions. The versatility and robustness of the protocol is justified by the results obtained in simulating health-care and emergency responder applications under Sybil and Wormhole attacks. The protocol considers metrics from each layer of the network model to obtain an optimal and feasible resource efficient solution. In the second tier, the emergent behavior of the protocol is further extended to mine information from the nodes to defend the network against denial-of-service attack using Bayesian models. The jammer attack is considered the most vulnerable attack, and therefore simulated vehicular ad-hoc network is experimented with varied types of jammer. Classification of the jammer under various attack scenarios is formulated to predict the genuineness of the attacks on the sensor nodes using receiver operating characteristics. In addition to detecting the jammer attack, a simple technique of locating the jammer under cooperative nodes is implemented. This feature enables the network in isolating the jammer or the reputation of node is affected, thus removing the malicious node from participating in future routes. Finally, a intrusion detection system using `bait\u27 architecture is analyzed where resources is traded-off for the sake of security due to sensitivity of the application. The architecture strategically enables ant agents to detect and track the intruders threateningthe network. The proposed framework is evaluated based on accuracy and speed of intrusion detection before the network is compromised. This process of detecting the intrusion earlier helps learn future attacks, but also serves as a defense countermeasure. The simulated scenarios of this dissertation show that Cognitive Security Framework isbest suited for both homogeneous and heterogeneous sensor networks

    A Technical Guide for Forest Nursery Management in the Caribbean and Latin America

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    A hatchery manual for the common, Chinese and Indian major carps (2nd rev ed.)

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    This major work on carp hatchery and nursery methods was part of an Asian Development Bank (ADB) project to improve carp seed production technology in ADB-member countries notably Bangladesh, Burma, Indonesia, Nepal, Pakistan and Sri Lanka. Designed as a reference source on carp seed production and as a mini-library for those stationed at seed production centers remote from scientific information channels.Fish culture, Hatcheries, Aquaculture techniques, Manuals Cyprinidae

    An evaluation of SEASAT-A candidate ocean industry economic verification experiments

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    A description of the candidate economic verification experiments which could be performed with SEASAT is provided. Experiments have been identified in each of the areas of ocean-based activity that are expected to show an economic impact from the use of operational SEASAT data. Experiments have been identified in the areas of Arctic operations, the ocean fishing industry, the offshore oil and natural gas industry, as well as ice monitoring and coastal zone applications

    12th EASN International Conference on "Innovation in Aviation & Space for opening New Horizons"

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    Epoxy resins show a combination of thermal stability, good mechanical performance, and durability, which make these materials suitable for many applications in the Aerospace industry. Different types of curing agents can be utilized for curing epoxy systems. The use of aliphatic amines as curing agent is preferable over the toxic aromatic ones, though their incorporation increases the flammability of the resin. Recently, we have developed different hybrid strategies, where the sol-gel technique has been exploited in combination with two DOPO-based flame retardants and other synergists or the use of humic acid and ammonium polyphosphate to achieve non-dripping V-0 classification in UL 94 vertical flame spread tests, with low phosphorous loadings (e.g., 1-2 wt%). These strategies improved the flame retardancy of the epoxy matrix, without any detrimental impact on the mechanical and thermal properties of the composites. Finally, the formation of a hybrid silica-epoxy network accounted for the establishment of tailored interphases, due to a better dispersion of more polar additives in the hydrophobic resin

    Comparative assessment of the vulnerability and resilience of 10 deltas : work document

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    Background information about: Nile delta (Egypt), Incomati delta (Mozambique), Ganges-Brahmaputra-Meghna (Bangladesh), Yangtze (China), Ciliwung (Indonesia), Mekong (Vietnam), Rhine-Meuse (The Netherlands), Danube (Romania), California Bay-Delta, Mississippi River Delta (USA

    The control of escape behaviour in, and the histopathology of, the Norway lobster, Nephrops norvegicus (L.)

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    Nephrops norvegicus, like other lobsters and crayfish, react to threatening stimuli by producing of the tail-flip escape response. This response, which is important in both predator avoidance and capture by trawling, takes the form of repeated flexions and extensions of the abdomen, produced by the deep abdominal flexor and extensor muscles. Much research has been concentrated on both the metabolic and neuronal factors controlling and limiting the tail-flip swimming of decapod Crustacea, but little attention has been focused upon the interactions between these two areas. This study has examined the tail-flip swimming of N.norvegicus in terms of both metabolic and neuronal limitations. Results have indicated that prolonged swimming and its recovery are limited neither by the availability of energy (from direct, stored sources - endogenous muscle ATP; or from indirect sources - by glycolytic production of ATP from D-glucose),nor by alteration of inter- or intra-cellular conditions by the build up of the glycolytic end product L-lactate. However, the part played by phospho-L-arginine (another short-term energy reserve in muscle) in the limitation of tail-flipping has not been unequivocally defined, and the possibility remains that there may be some metabolic influence in determining the endurance and recovery of swimming. Despite the lack of definitive evidence against any metabolic limitation of escape swimming, the results of further experiments suggest that neuronal factors play a major role in the limitation of tail-flipping. These experiments were designed to assess the importance and site of action of neuronal factors, in particular habituation, in swimming. Furthermore, the waning of tail-flipping in response to repeated stimulation appears to represent true habituation. By the use of both histochemical and morphological techniques, the roles of the muscles of the thoraco-abdominal joint in both tail-flipping and postural control have been partially elucidated. These results suggest both bracing and steering functions for the larger muscles of the two groups examined (thoraco-abdominal extensors and abdominal abductors) and postural roles for the smaller muscles. These investigations also identify suitable areas for further research, not least an examination of the innervation and recruitment of these muscle groups during tail-flipping in order to determine unequivocally their bracing and steering functions

    The value of apology: Apologies impact on stock returns

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    In a crisis managers are confronted with a dilemma between an ethical responsibility to respond to victims and their fiduciary responsibility to protect shareholder’s wealth. This study provides empirical evidence that a company apology made during a crisis can have a positive or negative effect on stock price depending on the level of responsibility for a crisis born by the firm. We use Coombs’ (2007) Situational Crisis Communication Theory to classify crises and appropriate re-sponse type for 235 unique crises between 1983 and 2013. We use event study methodology to study the effect of an apology on returns. The results show that managers apologizing to those affected for a victim or accidental crisis jeopardize shareholder wealth; however offering an apology for a preventable crisis offsets this negative effect
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