Interface Assignment-Based AODV Routing Protocol to Improve Reliability in Multi-Interface Multichannel Wireless Mesh Networks

Directory of Open Access Journals (Sweden)

Won-Suk Kim

2015-01-01

Full Text Available The utilization of wireless mesh networks (WMNs has greatly increased, and the multi-interface multichannel (MIMC technic has been widely used for the backbone network. Unfortunately, the ad hoc on-demand distance vector (AODV routing protocol defined in the IEEE 802.11s standard was designed for WMNs using the single-interface single-channel technic. So, we define a problem that happens when the legacy AODV is used in MIMC WMNs and propose an interface assignment-based AODV (IA-AODV in order to resolve that problem. IA-AODV, which is based on multitarget path request, consists of the PREQ prediction scheme, the PREQ loss recovery scheme, and the PREQ sender assignment scheme. A detailed operation according to various network conditions and services is introduced, and the routing efficiency and network reliability of a network using IA-AODV are analyzed over the presented system model. Finally, after a real-world test-bed for MIMC WMNs using the IA-AODV routing protocol is implemented, the various indicators of the network are evaluated through experiments. When the proposed routing protocol is compared with the existing AODV routing protocol, it performs the path update using only 14.33% of the management frames, completely removes the routing malfunction, and reduces the UDP packet loss ratio by 0.0012%.

Energy Reduction Multipath Routing Protocol for MANET Using Recoil Technique

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Rakesh Kumar Sahu

2018-04-01

Full Text Available In Mobile Ad-hoc networks (MANET, power conservation and utilization is an acute problem and has received significant attention from academics and industry in recent years. Nodes in MANET function on battery power, which is a rare and limited energy resource. Hence, its conservation and utilization should be done judiciously for the effective functioning of the network. In this paper, a novel protocol namely Energy Reduction Multipath Routing Protocol for MANET using Recoil Technique (AOMDV-ER is proposed, which conserves the energy along with optimal network lifetime, routing overhead, packet delivery ratio and throughput. It performs better than any other AODV based algorithms, as in AOMDV-ER the nodes transmit packets to their destination smartly by using a varying recoil off time technique based on their geographical location. This concept reduces the number of transmissions, which results in the improvement of network lifetime. In addition, the local level route maintenance reduces the additional routing overhead. Lastly, the prediction based link lifetime of each node is estimated which helps in reducing the packet loss in the network. This protocol has three subparts: an optimal route discovery algorithm amalgamation with the residual energy and distance mechanism; a coordinated recoiled nodes algorithm which eliminates the number of transmissions in order to reduces the data redundancy, traffic redundant, routing overhead, end to end delay and enhance the network lifetime; and a last link reckoning and route maintenance algorithm to improve the packet delivery ratio and link stability in the network. The experimental results show that the AOMDV-ER protocol save at least 16% energy consumption, 12% reduction in routing overhead, significant achievement in network lifetime and packet delivery ratio than Ad hoc on demand multipath distance vector routing protocol (AOMDV, Ad hoc on demand multipath distance vector routing protocol life

Performance Evaluation of AODV Routing Protocol in VANET with NS2

Directory of Open Access Journals (Sweden)

Divya Rathi

2017-03-01

Full Text Available In intelligent transportation systems, the collaboration between vehicles and the road side units is essential to bring these systems to realization. The emerging Vehicular Ad Hoc Network (VANET is becoming more and more important as it provides intelligent transportation application, comfort, safety, entertainment for people in vehicles. In order to provide stable routes and to get good performance in VANET, there is a need of proper routing protocols must be designed. In this paper, we are working with the very well-known ad-hoc on-demand distance vector (AODV routing protocol. The existing Routing protocol AODV-L which is based on the Link expiration time is extended to propose a more reliable AODV-AD which is based on multichannel MAC protocol. For the performance evaluation of routing protocols, a simulation tool ‘NS2’ has been used. Simulation results show that the proposed AODV-AD protocol can achieves better performances in forms of high Route stability, Packet Delivery ratio and packet loss rate than traditional AODV-L and traditional AODV.

RSRP: A Robust Secure Routing Protocol in MANET

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Sinha Ditipriya

2014-05-01

Full Text Available In this paper, we propose a novel algorithm RSRP to build a robust secure routing protocol in mobile ad-hoc networks (MANETs. This algorithm is based on some basic schemes such as RSA_CRT for encryption and decryption of messages; CRT for safety key generation, Shamir’s secret sharing principle for generation of secure routes. Those routes which are free from any malicious node and which belong to the set of disjoint routes between a source-destination pair are considered as probable routes. Shamir’s secret sharing principle is applied on those probable routes to obtain secure routes. Finally, most trustworthy and stable route is selected among those secure routes. Selection of the final route depends on some criteria of the nodes present in a route e.g.: battery power, mobility and trust value. In addition, complexity of key generation is reduced to a large extent by using RSA-CRT instead of RSA. In turn, the routing becomes less expensive and most secure and robust one. Performance of this routing protocol is then compared with non-secure routing protocols (AODV and DSR, secure routing scheme using secret sharing, security routing protocol using ZRP and SEAD depending on basic characteristics of these protocols. All such comparisons show that RSRP shows better performance in terms of computational cost, end-to-end delay and packet dropping in presence of malicious nodes in the MANET, keeping the overhead in terms of control packets same as other secure routing protocols.

Signcryption-Based Key Management for MANETs Applications in Mobile Commerce

Institute of Scientific and Technical Information of China (English)

LI Jingfeng; ZHU Yuefei; ZHANG Yajuan; PAN Heng

2006-01-01

Mobile commerce uses wireless device and wireless link to result in the transfer of values in exchange of information, services or goods. Wireless mobile ad hoc networks (MANETs) will bring a revolution to the business model of mobile commerce if such networks are used as the underlying network technology for mobile commerce. Mobile commerce will remain in a niche market until the security issue is properly addressed. Hence, security is also very important for MANET applications in mobile commerce. Robust key management is one of the most crucial technologies for security of MANETs. In this paper, a new solution for key management is proposed using identity-based (ID-based) signcryption and threshold secret sharing. It enables flexible and efficient key management while respecting the constraints of MANETs. In our solution, each mobile host uses its globally unique identity as its public key. It greatly decreases the computation and storage costs of mobile hosts, as well as communication cost for system key management.

An Enhanced Hybrid Social Based Routing Algorithm for MANET-DTN

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Martin Matis

2016-01-01

Full Text Available A new routing algorithm for mobile ad hoc networks is proposed in this paper: an Enhanced Hybrid Social Based Routing (HSBR algorithm for MANET-DTN as optimal solution for well-connected multihop mobile networks (MANET and/or worse connected MANET with small density of the nodes and/or due to mobility fragmented MANET into two or more subnetworks or islands. This proposed HSBR algorithm is fully decentralized combining main features of both Dynamic Source Routing (DSR and Social Based Opportunistic Routing (SBOR algorithms. The proposed scheme is simulated and evaluated by replaying real life traces which exhibit this highly dynamic topology. Evaluation of new proposed HSBR algorithm was made by comparison with DSR and SBOR. All methods were simulated with different levels of velocity. The results show that HSBR has the highest success of packet delivery, but with higher delay in comparison with DSR, and much lower in comparison with SBOR. Simulation results indicate that HSBR approach can be applicable in networks, where MANET or DTN solutions are separately useless or ineffective. This method provides delivery of the message in every possible situation in areas without infrastructure and can be used as backup method for disaster situation when infrastructure is destroyed.

Management of Energy Consumption on Cluster Based Routing Protocol for MANET

Science.gov (United States)

Hosseini-Seno, Seyed-Amin; Wan, Tat-Chee; Budiarto, Rahmat; Yamada, Masashi

The usage of light-weight mobile devices is increasing rapidly, leading to demand for more telecommunication services. Consequently, mobile ad hoc networks and their applications have become feasible with the proliferation of light-weight mobile devices. Many protocols have been developed to handle service discovery and routing in ad hoc networks. However, the majority of them did not consider one critical aspect of this type of network, which is the limited of available energy in each node. Cluster Based Routing Protocol (CBRP) is a robust/scalable routing protocol for Mobile Ad hoc Networks (MANETs) and superior to existing protocols such as Ad hoc On-demand Distance Vector (AODV) in terms of throughput and overhead. Therefore, based on this strength, methods to increase the efficiency of energy usage are incorporated into CBRP in this work. In order to increase the stability (in term of life-time) of the network and to decrease the energy consumption of inter-cluster gateway nodes, an Enhanced Gateway Cluster Based Routing Protocol (EGCBRP) is proposed. Three methods have been introduced by EGCBRP as enhancements to the CBRP: improving the election of cluster Heads (CHs) in CBRP which is based on the maximum available energy level, implementing load balancing for inter-cluster traffic using multiple gateways, and implementing sleep state for gateway nodes to further save the energy. Furthermore, we propose an Energy Efficient Cluster Based Routing Protocol (EECBRP) which extends the EGCBRP sleep state concept into all idle member nodes, excluding the active nodes in all clusters. The experiment results show that the EGCBRP decreases the overall energy consumption of the gateway nodes up to 10% and the EECBRP reduces the energy consumption of the member nodes up to 60%, both of which in turn contribute to stabilizing the network.

Trust Based Algorithm for Candidate Node Selection in Hybrid MANET-DTN

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Jan Papaj

2014-01-01

Full Text Available The hybrid MANET - DTN is a mobile network that enables transport of the data between groups of the disconnected mobile nodes. The network provides benefits of the Mobile Ad-Hoc Networks (MANET and Delay Tolerant Network (DTN. The main problem of the MANET occurs if the communication path is broken or disconnected for some short time period. On the other side, DTN allows sending data in the disconnected environment with respect to higher tolerance to delay. Hybrid MANET - DTN provides optimal solution for emergency situation in order to transport information. Moreover, the security is the critical factor because the data are transported by mobile devices. In this paper, we investigate the issue of secure candidate node selection for transportation of the data in a disconnected environment for hybrid MANET- DTN. To achieve the secure selection of the reliable mobile nodes, the trust algorithm is introduced. The algorithm enables select reliable nodes based on collecting routing information. This algorithm is implemented to the simulator OPNET modeler.

BARTER: Behavior Profile Exchange for Behavior-Based Admission and Access Control in MANETs

Science.gov (United States)

Frias-Martinez, Vanessa; Stolfo, Salvatore J.; Keromytis, Angelos D.

Mobile Ad-hoc Networks (MANETs) are very dynamic networks with devices continuously entering and leaving the group. The highly dynamic nature of MANETs renders the manual creation and update of policies associated with the initial incorporation of devices to the MANET (admission control) as well as with anomaly detection during communications among members (access control) a very difficult task. In this paper, we present BARTER, a mechanism that automatically creates and updates admission and access control policies for MANETs based on behavior profiles. BARTER is an adaptation for fully distributed environments of our previously introduced BB-NAC mechanism for NAC technologies. Rather than relying on a centralized NAC enforcer, MANET members initially exchange their behavior profiles and compute individual local definitions of normal network behavior. During admission or access control, each member issues an individual decision based on its definition of normalcy. Individual decisions are then aggregated via a threshold cryptographic infrastructure that requires an agreement among a fixed amount of MANET members to change the status of the network. We present experimental results using content and volumetric behavior profiles computed from the ENRON dataset. In particular, we show that the mechanism achieves true rejection rates of 95% with false rejection rates of 9%.

Power Management Based Grid Routing Protocol for IEEE 802.11 Based MANET

Institute of Scientific and Technical Information of China (English)

XU Li; ZHENG Bao-yu; YANG Zhen

2004-01-01

MANET ( Mobile Ad Hoc Network ) is a collection of wireless mobile nodes forming a temporary communication network without the aid of any established infrastructure or centralized administration. The lifetime of a MANET depends on the battery resources of the mobile nodes. So energy consumption may one of important design criterions for MANET. With changing the idle model to sleep model in the grid environment, this paper proposes a new energy-aware routing protocol. Performance simulation results show that the proposed strategy can dynamic balance the traffic load inside the whole network, extend the lifetime of a MANET, and without decreasing the throughput ratio.

Verifikasi Dua Varian Protokol Ad hoc On demand Distance Vector dengan UPPAAL

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Ika Oktavia Suzanti

2015-01-01

Abstract  MANET is a group of wireless mobile that connected one to each other without fixed infrastructure so topology could change at anytime. MANET routing protocol has two models which are reactive routing protocol that built routing table only when needed and proactive routing protocol that maintain routing table periodically. General property which had to be satisfied by ad-hoc network protocol are route discovery, packet delivery and loop freedom. AODV is a reactive protocol in MANET that has time standard to determine how long a route is valid to be used (route validity so route discovery and packet delivery property should be satisfied in a specifically certain time. Protocol verification process done by modeling protocol specification using technique, tool and mathematic language. In this research protocol modeled using timed automata which is a modeling language that could be used to model a time dependent system in each process. Verification using timed automata can automatically done by UPPAAL tool model checker. Protocol which will be verified are AODV Break Avoidance by Ali Khosrozadeh et al. and AODV Reliable Delivery by Liu Jian and Fang-Min. Result of this protocol verification prove that AODV BA could satisfied route discovery property and AODV Reliable Delivery could satisfied packet delivery property within their specification time.   Keywords—Protocol Verification, Timed Automata, AODV, UPPAAL

Evaluación del retardo de los protocolos de ruteo reactivos para redes Manet

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Matías Martínez

2010-07-01

Full Text Available Las redes inalámbricas han tenido un gran impacto en la industria y en los ámbitos académicos. Las MANETs (Mobile Ad-hoc NETwork agregan a las limitaciones de las redes inalámbricas características de movilidad, debido a esto, mantener la QoS (Quality of Service en este tipo de redes se hace imposible implementando los modelos tradicionales. Una característica importante que deben poseer los protocolos de ruteo para MANETs es que deben poder adaptarse rápidamente a lo cambios continuos de la red, con el fin de mantener las rutas entre los nodos que se están comunicando. Un protocolo de ruteo con capacidades de administrar las necesidades de QoS de las aplicaciones debería intentar establecer una ruta que satisficiese los requisitos de ancho de banda, retardo, jitter, etc. Inicialmente los protocolos reactivos serían más interesantes debido a su menor uso de recursos de red. En este trabajo se presentan resultados de simulaciones obtenidos con los protocolos bajo demanda AODV (Ad hoc On-Demand Distance Vector y DSR (Dynamic Source Routing. La elección se debe a que estos dos protocolos son los más conocidos dentro de los protocolos reactivos y son ampliamente utilizados como referencia para la comparación con las nuevas propuestas.

Ad Hoc on-Demand Distance Vector (AODV Routing Protocol Performance Evaluation on Hybrid Ad Hoc Network: Comparison of Result of Ns-2 Simulation and Implementation on Testbed using PDA

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Riri Sari

2010-10-01

Full Text Available In Mobile Ad hoc NETwork (MANET, node supplemented with wireless equipment has the capacity to manage and organise autonomously, without the presence of network infrastructures. Hybrid ad hoc network, enable several nodes to move freely (mobile to create instant communication. Independent from infrastructure. They could access the Local Area Network (LAN or the Internet. Functionalities of ad hoc network very much dependent on the routing protocol that determines the routing around node. Ad hoc On-demand Distance Vector (AODV is one of routing protocols in ad hoc network which has a reactive characteristic. This protocol is the most common protocol being researched and used. In this Research, AODV protocol investigation was conducted by developing a testbed using Personal Computer, several Laptops (the Linux Red Hat operation system 9.0 and Fedora Core 2, and Personal Digital Assistant (PDA. This research also made a complete package by mean of cross compilation for PDA iPAQ. In general, results obtained from the simulation of AODV protocol using Network Simulator NS-2 are packet delivery ratio 99.89%, end-to-end delay of 0.14 seconds and routing overhead of 1,756.61 byte per second. Afterwards results from simulation were compared to results from testbed. Results obtained from testbed are as follows: the packet delivery ratio is 99.57%, the end-to-end delay is 1.004 seconds and the routing overhead is 1,360.36 byte per second.

Detecting and Mitigating Smart Insider Jamming Attacks in MANETs Using Reputation-Based Coalition Game

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Ashraf Al Sharah

2016-01-01

Full Text Available Security in mobile ad hoc networks (MANETs is challenging due to the ability of adversaries to gather necessary intelligence to launch insider jamming attacks. The solutions to prevent external attacks on MANET are not applicable for defense against insider jamming attacks. There is a need for a formal framework to characterize the information required by adversaries to launch insider jamming attacks. In this paper, we propose a novel reputation-based coalition game in MANETs to detect and mitigate insider jamming attacks. Since there is no centralized controller in MANETs, the nodes rely heavily on availability of transmission rates and a reputation for each individual node in the coalition to detect the presence of internal jamming node. The nodes will form a stable grand coalition in order to make a strategic security defense decision, maintain the grand coalition based on node reputation, and exclude any malicious node based on reputation value. Simulation results show that our approach provides a framework to quantify information needed by adversaries to launch insider attacks. The proposed approach will improve MANET’s defense against insider attacks, while also reducing incorrect classification of legitimate nodes as jammers.

A New MANET Wormhole Detection Algorithm Based on Traversal Time and Hop Count Analysis

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Göran Pulkkis

2011-11-01

Full Text Available As demand increases for ubiquitous network facilities, infrastructure-less and self-configuring systems like Mobile Ad hoc Networks (MANET are gaining popularity. MANET routing security however, is one of the most significant challenges to wide scale adoption, with wormhole attacks being an especially severe MANET routing threat. This is because wormholes are able to disrupt a major component of network traffic, while concomitantly being extremely difficult to detect. This paper introduces a new wormhole detection paradigm based upon Traversal Time and Hop Count Analysis (TTHCA, which in comparison to existing algorithms, consistently affords superior detection performance, allied with low false positive rates for all wormhole variants. Simulation results confirm that the TTHCA model exhibits robust wormhole route detection in various network scenarios, while incurring only a small network overhead. This feature makes TTHCA an attractive choice for MANET environments which generally comprise devices, such as wireless sensors, which possess a limited processing capability.

Mobility-Aware and Load Balancing Based Clustering Algorithm for Energy Conservation in MANET

Institute of Scientific and Technical Information of China (English)

XU Li; ZHENG Bao-yu; GUO Gong-de

2005-01-01

Mobile ad hoc network (MANET) is one of wireless communication network architecture that has received a lot of attention. MANET is characterized by dynamic network topology and limited energy. With mobility-aware and load balancing based clustering algorithm (MLCA), this paper proposes a new topology management strategy to conserve energy. Performance simulation results show that the proposed MLCA strategy can balances the traffic load inside the whole network, so as to prolong the network lifetime, meanly, at the same time, achieve higher throughput ratio and network stability.

Real-world Bluetooth MANET Java Middleware

DEFF Research Database (Denmark)

Glenstrup, Arne John; Nielsen, Michael; Skytte, Frederik

We present BEDnet, a Java based middleware for creating and maintaining a Bluetooth based mobile ad-hoc network (MANET). MANETs are key to nomadic computing: Mobile units can set up spontaneous local networks when needed, removing the need for fixed network infrastructure, either as wireless access....... Based on the Java JSR-82 specification, BEDnet is portable to a wide selection of mobile phones, and is publicly available as open source software. Experiments show that e.g. media streaming over Bluetooth is feasible, and that BEDnet is able to set up a scatternet within a couple of minutes...

Performance Analysis of AODV Routing Protocol for Wireless Sensor Network based Smart Metering

International Nuclear Information System (INIS)

Farooq, Hasan; Jung, Low Tang

2013-01-01

Today no one can deny the need for Smart Grid and it is being considered as of utmost importance to upgrade outdated electric infrastructure to cope with the ever increasing electric load demand. Wireless Sensor Network (WSN) is considered a promising candidate for internetworking of smart meters with the gateway using mesh topology. This paper investigates the performance of AODV routing protocol for WSN based smart metering deployment. Three case studies are presented to analyze its performance based on four metrics of (i) Packet Delivery Ratio, (ii) Average Energy Consumption of Nodes (iii) Average End-End Delay and (iv) Normalized Routing Load.

On the Performance of the Current MANET Routing Protocols for VoIP, HTTP, and FTP Applications

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Waheb A. Jabbar

2014-01-01

Full Text Available The recent advances of ensemble mobile environment of smart devices with embedded sensors have enabled the MANET to play a key role in the smart cities as well as WSN and WMN. However, these smart devices are still limited in terms of energy, processor, and memory. Moreover, the efficient routing for reliable network connectivity at anytime, anywhere, and about everything is still a challenge in multihop wireless networks. This paper evaluates the QoS and energy efficiency of three active routing protocols: (i OLSRv2, a successor to OLSR, (ii DYMO, a successor to both DSR and AODV, and (iii MP-OLSR multipath extension to OLSRv2. In contrast to the related previous works which focused only on CBR traffic without considering the influence of specific traffic types on the performance of routing protocols, this work focused on this area from a different perspective. It evaluates the performance of three internet-based traffic types that can be used in the smart city applications: VoIP, HTTP, and FTP using different simulation models. The impact of the network density, load traffic, and nodes mobility on the considered protocols was evaluated by considering particular performance metrics for each traffic application. Based on the results, the study concludes by presenting useful recommendations for future work.

Analysis of MANET Security, Architecture and Assessment

OpenAIRE

Sweta Kaushik; Manorma Kaushik

2012-01-01

in these days, the Mobile ad hoc network (MANET) technology spreads widely. Architecture and security issue is the most sensitive challenge of MANET. MANET support to nodes for directly communications with all the other nodes within their radio ranges through multiple wireless links, where the nodes are not in the direct communication range using intermediate node(s) to communicate with each other. In a MANET, the users’ mobile devices behave as a network, and they must cooperatively provide ...

A Cross-Layer, Anomaly-Based IDS for WSN and MANET.

Science.gov (United States)

Amouri, Amar; Morgera, Salvatore D; Bencherif, Mohamed A; Manthena, Raju

2018-02-22

Intrusion detection system (IDS) design for mobile adhoc networks (MANET) is a crucial component for maintaining the integrity of the network. The need for rapid deployment of IDS capability with minimal data availability for training and testing is an important requirement of such systems, especially for MANETs deployed in highly dynamic scenarios, such as battlefields. This work proposes a two-level detection scheme for detecting malicious nodes in MANETs. The first level deploys dedicated sniffers working in promiscuous mode. Each sniffer utilizes a decision-tree-based classifier that generates quantities which we refer to as correctly classified instances (CCIs) every reporting time. In the second level, the CCIs are sent to an algorithmically run supernode that calculates quantities, which we refer to as the accumulated measure of fluctuation (AMoF) of the received CCIs for each node under test (NUT). A key concept that is used in this work is that the variability of the smaller size population which represents the number of malicious nodes in the network is greater than the variance of the larger size population which represents the number of normal nodes in the network. A linear regression process is then performed in parallel with the calculation of the AMoF for fitting purposes and to set a proper threshold based on the slope of the fitted lines. As a result, the malicious nodes are efficiently and effectively separated from the normal nodes. The proposed scheme is tested for various node velocities and power levels and shows promising detection performance even at low-power levels. The results presented also apply to wireless sensor networks (WSN) and represent a novel IDS scheme for such networks.

CROSS LAYER COORDINATED ENERGY SAVING STRATEGY IN MANET

Institute of Scientific and Technical Information of China (English)

Xu Li; Zheng Baoyu

2003-01-01

Mobile Ad hoc NETwork (MANET) consists of a set of mobile hosts which can operate independently without infrastructure base stations. Energy saving is a critical issue for MANET since most mobile hosts will operate on battery powers. A cross layer coordinated framework for energy saving is proposed in this letter. On-demand power management, physical layer and medium access control layer dialogue based multi-packet reception, mobile agent based topology discovery and topology control based transmit power-aware and battery power-aware dynamic source routing are some of new ideas in this framework.

Sadhana | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Sadhana. M G SUMITHRA. Articles written in Sadhana. Volume 43 Issue 4 April 2018 pp 60. Preventing the impact of selfish behavior under MANET using Neighbor Credit Value based AODV routing algorithm · K RAMA ABIRAMI M G SUMITHRA · More Details Abstract Fulltext PDF. Mobile Ad hoc Network ...

SECURE SERVICE DISCOVERY BASED ON PROBE PACKET MECHANISM FOR MANETS

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S. Pariselvam

2015-03-01

Full Text Available In MANETs, Service discovery process is always considered to be crucial since they do not possess a centralized infrastructure for communication. Moreover, different services available through the network necessitate varying categories. Hence, a need arises for devising a secure probe based service discovery mechanism to reduce the complexity in providing the services to the network users. In this paper, we propose a Secure Service Discovery Based on Probe Packet Mechanism (SSDPPM for identifying the DoS attack in MANETs, which depicts a new approach for estimating the level of trust present in each and every routing path of a mobile ad hoc network by using probe packets. Probing based service discovery mechanisms mainly identifies a mobile node’s genuineness using a test packet called probe that travels the entire network for the sake of computing the degree of trust maintained between the mobile nodes and it’s attributed impact towards the network performance. The performance of SSDPPM is investigated through a wide range of network related parameters like packet delivery, throughput, Control overhead and total overhead using the version ns-2.26 network simulator. This mechanism SSDPPM, improves the performance of the network in an average by 23% and 19% in terms of packet delivery ratio and throughput than the existing service discovery mechanisms available in the literature.

SIP Signaling Implementations and Performance Enhancement over MANET: A Survey

OpenAIRE

Alshamrani, M; Cruickshank, Haitham; Sun, Zhili; Ansa, G; Alshahwan, F

2016-01-01

The implementation of the Session Initiation Protocol (SIP)-based Voice over Internet Protocol (VoIP) and multimedia over MANET is still a challenging issue. Many routing factors affect the performance of SIP signaling and the voice Quality of Service (QoS). Node mobility in MANET causes dynamic changes to route calculations, topology, hop numbers, and the connectivity status between the correspondent nodes. SIP-based VoIP depends on the caller’s registration, call initiation, and call termin...

OPTIMAL DATA REPLACEMENT TECHNIQUE FOR COOPERATIVE CACHING IN MANET

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P. Kuppusamy

2014-09-01

Full Text Available A cooperative caching approach improves data accessibility and reduces query latency in Mobile Ad hoc Network (MANET. Maintaining the cache is challenging issue in large MANET due to mobility, cache size and power. The previous research works on caching primarily have dealt with LRU, LFU and LRU-MIN cache replacement algorithms that offered low query latency and greater data accessibility in sparse MANET. This paper proposes Memetic Algorithm (MA to locate the better replaceable data based on neighbours interest and fitness value of cached data to store the newly arrived data. This work also elects ideal CH using Meta heuristic search Ant Colony Optimization algorithm. The simulation results shown that proposed algorithm reduces the latency, control overhead and increases the packet delivery rate than existing approach by increasing nodes and speed respectively.

When Reputation Enforces Evolutionary Cooperation in Unreliable MANETs.

Science.gov (United States)

Tang, Changbing; Li, Ang; Li, Xiang

2015-10-01

In self-organized mobile ad hoc networks (MANETs), network functions rely on cooperation of self-interested nodes, where a challenge is to enforce their mutual cooperation. In this paper, we study cooperative packet forwarding in a one-hop unreliable channel which results from loss of packets and noisy observation of transmissions. We propose an indirect reciprocity framework based on evolutionary game theory, and enforce cooperation of packet forwarding strategies in both structured and unstructured MANETs. Furthermore, we analyze the evolutionary dynamics of cooperative strategies and derive the threshold of benefit-to-cost ratio to guarantee the convergence of cooperation. The numerical simulations verify that the proposed evolutionary game theoretic solution enforces cooperation when the benefit-to-cost ratio of the altruistic exceeds the critical condition. In addition, the network throughput performance of our proposed strategy in structured MANETs is measured, which is in close agreement with that of the full cooperative strategy.

A Simulation Study: The Impact of Random and Realistic Mobility Models on the Performance of Bypass-AODV in Ad Hoc Wireless Networks

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Baroudi Uthman

2010-01-01

Full Text Available To bring VANET into reality, it is crucial to devise routing protocols that can exploit the inherited characteristics of VANET environment to enhance the performance of the running applications. Previous studies have shown that a certain routing protocol behaves differently under different presumed mobility patterns. Bypass-AODV is a new optimization of the AODV routing protocol for mobile ad-hoc networks. It is proposed as a local recovery mechanism to enhance the performance of the AODV routing protocol. It shows outstanding performance under the Random Waypoint mobility model compared with AODV. However, Random Waypoint is a simple model that may be applicable to some scenarios but it is not sufficient to capture some important mobility characteristics of scenarios where VANETs are deployed. In this paper, we will investigate the performance of Bypass-AODV under a wide range of mobility models including other random mobility models, group mobility models, and vehicular mobility models. Simulation results show an interesting feature that is the insensitivity of Bypass-AODV to the selected random mobility model, and it has a clear performance improvement compared to AODV. For group mobility model, both protocols show a comparable performance, but for vehicular mobility models, Bypass-AODV suffers from performance degradation in high-speed conditions.

Manet key management via Mobile Ficlke Key protocol (MFK ...

African Journals Online (AJOL)

Manet key management via Mobile Ficlke Key protocol (MFK) ... Journal of Fundamental and Applied Sciences. Journal Home · ABOUT THIS JOURNAL ... No Abstract. Keywords: MANET; key management scheme; simulation environment ...

Collective Study On Security Threats In MANET

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Muhammad Zunnurain Hussain

2017-01-01

Full Text Available In this paper the authors will be discussing the security issues in MANET amp the methods to protect it. Authors will be talk about related work in securing the network different type of attacks how to sense these sorts of attack what are the features of MANET then will be describing what the requirements for securing network are. Investigation had been done in past to maintain the network from attacks but due to the feature of MANET inappropriate infrastructure and due to the disperse network quality it is open to attack. Authors will be tackling the defence against each attack. Solution has been suggested So that the users can use proper authentication techniques and network resources can be properly utilized.

ZONE BASED PATH ROUTING APPROACH FOR THE DETECTION AND PREVENTION OF MALICIOUS BEHAVIOUR OF THE NODE IN MANET

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Akansha Shrivastava

2016-09-01

Full Text Available Mobile Ad-hoc Network (MANET is one of the important research areas. MANET is a cluster of movable nodes that communicate without any wired connection. It refers to a network of moving nodes communicating with other mobile nodes in a multi-hop fashion. Mobile nodes provide flexibility to this network. Thus this flexible network is prone to a variety of attacks. Wormhole attack is a major threat to this network. In this attack, a tunnel is created between two nodes. These nodes transmit all communication through this tunnel. Detecting such attack is a major task. This paper presents a zone-based approach that detects and prevents such attack.

Fuzzy Based PC-PUSH in CR-MANETs

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S. Nejatian

2014-01-01

Full Text Available In cognitive radio (CR, the secondary user (SU needs to hand off its ongoing communication to an idle channel in order to avoid interference to the primary user (PU. Spectrum hand off issue becomes challenging in CR mobile ad hoc networks (CR-MANETs because of the uncertainty in spectrum availability, broad range of spectrum bands and lack of central entity. The purpose of this study is to design a unified spectrum handoff (USH scheme for CR-MANETs that considers the spectrum heterogeneity and its availability over time and space. A local flow hand off is performed when spectrum hand off cannot be carried out due to the SUs mobility. To improve further USH, preemptive unified spectrum handoff (PUSH algorithm is proposed in which two different preemptive hand off threshold regions are defined. The PUSH algorithm also predicts the cognitive link availability considering the PU interference boundary. Although the PUSH scheme improves the hand off performance, the number of spectrum hand offs due to the PU activity should be reduced in this scheme. Therefore, the PC-PUSH (Power Controller-PUSH scheme is proposed in which the fuzzy logic is used to improve the PUSH in terms of the number of spectrum handoffs because of the PU activity. The PC-PUSH decreases the interference to the PUs, while reducing the number of spectrum handoffs. The results show that the proposed scheme improves the link maintenance probability, decreases the hand off delay, and reduces the number of spectrum handoffs.

Illustration, detection and prevention of sleep deprivation anomaly in mobile ad hoc networks

International Nuclear Information System (INIS)

Nadeem, A.; Ahsan, K.; Sarim, M.

2017-01-01

MANETs (Mobile Ad Hoc Networks) have applications in various walks of life from rescue operations to battle field operations, personal and commercial. However, routing operations in MANETs are still vulnerable to anomalies and DoS (Denial of Service) attacks such as sleep deprivation. In SD (Sleep Deprivation) attack malicious node exploits the vulnerability in the route discovery function of the reactive routing protocol for example AODV (Ad Hoc On-Demand Distance Vector). In this paper, we first illustrate the SD anomaly in MANETs and then propose a SD detection and prevention algorithm which efficiently deals with this attack. We assess the performance of our proposed approach through simulation, evaluating its successfulness using different network scenarios. (author)

Efficient Certification Path Discovery for MANET

Directory of Open Access Journals (Sweden)

Kambourakis Georgios

2010-01-01

Full Text Available A Mobile Ad Hoc Network (MANET is characterized by the lack of any infrastructure, absence of any kind of centralized administration, frequent mobility of nodes, network partitioning, and wireless connections. These properties make traditional wireline security solutions not straightforwardly applicable in MANETs, and of course, constitute the establishment of a Public Key Infrastructure (PKI in such networks a cumbersome task. After surveying related work, we propose a novel public key management scheme using the well-known web-of-trust or trust graph model. Our scheme is based on a binary tree formation of the network's nodes. The binary tree structure is proved very effective for building certificate chains between communicating nodes that are multihops away and the cumbersome problem of certificate chain discovery is avoided. We compare our scheme with related work and show that it presents several advantages, especially when a fair balancing between security and performance is desirable. Simulations of the proposed scheme under different scenarios demonstrate that it is effective in terms of tree formation, join and leave occurrences, and certificate chain establishment.

Édouard Manet's Tabes Dorsalis: From Painful Ataxia to Phantom Limb.

Science.gov (United States)

Bogousslavsky, Julien; Tatu, Laurent

2016-01-01

Édouard Manet (1832-1883) is considered the 'father' of Impressionism and even of XXth century modern art. Manet's genius involved getting away from the classical narrative or historical topics and replacing them by the banality of daily life. Technically, he erased volumes into flat two-dimensional coloured planes, and distorted conventional perspective with often gross brushstrokes intentionally giving an 'unfinished' aspect to the work. It is little known that Manet had a very painful second part of his life, due to excruciating limb and chest pains, which developed in parallel with proprioceptive ataxia and gait imbalance. Manet always remained discreet about his private life, and we mainly know that his future wife was his family piano teacher, with whom he had a liaison already at age 17. Later, the great but platonic passion of his life was the painter Berthe Morisot (1841-1895), who got married to Manet's brother Eugène. In fact, we do not know whether he had any mistress at all, although he had several elegant 'flirts' in the mundane and artistic milieu. Thus, while Manet's progressive painful ataxia from age 40 yields little doubt on its tabetic origin, how he contracted syphilis at least 15-20 years before will probably remain a mystery. It is fascinating that Manet's daily struggle against pain and poor coordination may have led his art to become one of the most significant of modern times, opening the way to XXth century avant-gardes, along with another victim of syphilis, Paul Gauguin (1848-1903). Manet never showed any sign of General Paresis, and like his contemporary the writer Alphonse Daudet, his clinical picture remained dominated by paroxysmal pain and walking impairment. Difficult hand coordination made him quit watercolor painting, and during the last 2 years of his life, he had to focus on small format oil works, whose subject was nearly limited to modest bunches of fresh flowers, now often considered to be his maturity masterpieces

Sensors for Detection of Misbehaving Nodes in MANETs

OpenAIRE

Klenk, Andreas; Kragl, Frank; Schlott, Stefan; Weber, Michael

2004-01-01

The fact that security is a critical problem when implementing mobile ad hoc networks (MANETs) is widely acknowledged. One of the different kinds of misbehavior a node may exhibit is selfishness. A selfish node wants to preserve its resources while using the services of others and consuming their resources. One way of preventing selfishness in a MANET is a detection and exclusion mechanism. In this paper, we focus on the detection and present different kinds of sensors that wil...

Power Balance AODV Routing Algorithm of WSN in Precision Agriculture Environment Monitoring

Directory of Open Access Journals (Sweden)

Xiaoqin Qin

2013-11-01

Full Text Available As one of important technologies of IOT (Internet of Things, WSN (Wireless Sensor Networks has been widely used in precision agriculture environment monitoring. WSN is a kind of energy-constrained network, but power balance is not taken into account in traditional routing protocols. A novel routing algorithm, named Power Balance Ad hoc On-Demand Distance Vector (PB-AODV, is proposed on cross-layer design. In the route discovery process of PB-AODV, routing path is established by the Received Signal Strength Indication (RSSI value. The optimal transmitting power, which is computed according to RSSI value, power threshold and node’s surplus energy, is encapsulated into Route Reply Packet. Hence, the sender node can adjust its transmission power to save energy according to the Route Reply Packet. Simulation results show that the proposed algorithm is effective for load balancing, and increases the WSN’s lifetime 14.3% consequently.

A Multi-Hop Advertising Discovery and Delivering Protocol for Multi Administrative Domain MANET

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Federico Mari

2013-01-01

Full Text Available A Mobile Ad-hoc NETwork (MANET is Multi Administrative Domain (MAD if each network node belongs to an independent authority, that is each node owns its resources and there is no central authority owning all network nodes. One of the main obstructions in designing Service Advertising, Discovery and Delivery (SADD protocol for MAD MANETs is the fact that, in an attempt to increase their own visibility, network nodes tend to flood the network with their advertisements. In this paper, we present a SADD protocol for MAD MANET, based on Bloom filters, that effectively prevents advertising floods due to such misbehaving nodes. Our results with the ns-2 simulator show that our SADD protocol is effective in counteracting advertising floods, it keeps low the collision rate as well as the energy consumption while ensuring that each peer receives all messages broadcasted by other peers.

Enhanced DSR Routing Protocol for the Short Time Disconnected MANET

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PAPAJ Ján

2013-05-01

Full Text Available Data delivery in Mobile Ad-Hoc network (MANET is a very difficult task due to the fact the sporadic connections between mobile nodes. For this reason, we introduce the new modified routing protocol that enables the data delivery in the case that the connections are disconnected. A key aspect of the protocol is a process of finding connections between source and destination nodes that can provide low end-to-end delay and better delivery performance in a disconnected MANET. The protocol provides the concepts of opportunistic routing of the routing packets in disconnected MANETs. In this paper we present a modification of the DSR routing protocol and also some results of a simulation.

ANALISIS TRANSFER RATE PENAMBAHAN NODE PADA INFRASTRUKTUR MOBILE ADHOC NETWORK (MANET UNTUK FILE SERVER

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Rudi Kurniawan

2017-05-01

Full Text Available Teknologi Wireless Network sudah lama ditemukan dan seiring waktu juga mengalami perkembangan, Namun sifat teknologi ini menggantungkan diri pada infrastruktur jaringan yang ada. Hal ini bias menjadi kelemahan tersendiri saat kondisi infrastruktur jaringan sedang mengalami gangguan, karena setiap komunikasi yang melewati infrastruktur jaringan tersebut tidak akan sampai pada tujuan. Teknologi jaringan Mobile Ad-hoc Network (MANET diciptakan sebagai antisipasi jika infrastruktur jaringan sedang mengalami gangguan. Dengan jaringan MANET sistem komunikasi yang dilakukan tidak membutuhkan infrastruktur jaringan karena tiap node pada jaringan tersebut bersifat mobile. Untuk menguji kemampuan MANET, pada penelitian ini akan menerapkan File Transfer Protocol (FTP sebagai media untuk melakukan komunikasi data file transfer yang diimplementasi pada jaringan MANET. Dari pengujian yang telah dilakukan diperoleh hasil bahwa File Transfer dapat berfungsi dengan baik saat diterapkan pada jaringan MANET.

A Dynamic Probabilistic Based Broadcasting Scheme for MANETs

Science.gov (United States)

Shanmugam, Kannan; Subburathinam, Karthik; Velayuthampalayam Palanisamy, Arunachalam

2016-01-01

MANET is commonly known as Mobile Ad Hoc Network in which cluster of mobile nodes can communicate with each other without having any basic infrastructure. The basic characteristic of MANET is dynamic topology. Due to the dynamic behavior nature, the topology of the network changes very frequently, and this will lead to the failure of the valid route repeatedly. Thus, the process of finding the valid route leads to notable drop in the throughput of the network. To identify a new valid path to the targeted mobile node, available proactive routing protocols use simple broadcasting method known as simple flooding. The simple flooding method broadcasts the RREQ packet from the source to the rest of the nodes in mobile network. But the problem with this method is disproportionate repetitive retransmission of RREQ packet which could result in high contention on the available channel and packet collision due to extreme traffic in the network. A reasonable number of routing algorithms have been suggested for reducing the lethal impact of flooding the RREQ packets. However, most of the algorithms have resulted in considerable amount of complexity and deduce the throughput by depending on special hardware components and maintaining complex information which will be less frequently used. By considering routing complexity with the goal of increasing the throughput of the network, in this paper, we have introduced a new approach called Dynamic Probabilistic Route (DPR) discovery. The Node's Forwarding Probability (NFP) is dynamically calculated by the DPR mobile nodes using Probability Function (PF) which depends on density of local neighbor nodes and the cumulative number of its broadcast covered neighbors. PMID:27019868

Energy Efficient MANET Routing Using a Combination of Span and BECA/AFECA

DEFF Research Database (Denmark)

Kristensen, Mads Darø; Bouvin, Niels Olof

2008-01-01

This paper presents some novel approaches for energy efficient routing in mobile ad-hoc networks. Two known energy preserving techniques, Span and BECA/AFECA, are combined with a well-known re-active routing protocol, AODV, to create a new energy efficient routing protocol. Furthermore, the proto......This paper presents some novel approaches for energy efficient routing in mobile ad-hoc networks. Two known energy preserving techniques, Span and BECA/AFECA, are combined with a well-known re-active routing protocol, AODV, to create a new energy efficient routing protocol. Furthermore...

Secure and Fair Cluster Head Selection Protocol for Enhancing Security in Mobile Ad Hoc Networks

Directory of Open Access Journals (Sweden)

B. Paramasivan

2014-01-01

Full Text Available Mobile ad hoc networks (MANETs are wireless networks consisting of number of autonomous mobile devices temporarily interconnected into a network by wireless media. MANETs become one of the most prevalent areas of research in the recent years. Resource limitations, energy efficiency, scalability, and security are the great challenging issues in MANETs. Due to its deployment nature, MANETs are more vulnerable to malicious attack. The secure routing protocols perform very basic security related functions which are not sufficient to protect the network. In this paper, a secure and fair cluster head selection protocol (SFCP is proposed which integrates security factors into the clustering approach for achieving attacker identification and classification. Byzantine agreement based cooperative technique is used for attacker identification and classification to make the network more attack resistant. SFCP used to solve this issue by making the nodes that are totally surrounded by malicious neighbors adjust dynamically their belief and disbelief thresholds. The proposed protocol selects the secure and energy efficient cluster head which acts as a local detector without imposing overhead to the clustering performance. SFCP is simulated in network simulator 2 and compared with two protocols including AODV and CBRP.

Secure and fair cluster head selection protocol for enhancing security in mobile ad hoc networks.

Science.gov (United States)

Paramasivan, B; Kaliappan, M

2014-01-01

Mobile ad hoc networks (MANETs) are wireless networks consisting of number of autonomous mobile devices temporarily interconnected into a network by wireless media. MANETs become one of the most prevalent areas of research in the recent years. Resource limitations, energy efficiency, scalability, and security are the great challenging issues in MANETs. Due to its deployment nature, MANETs are more vulnerable to malicious attack. The secure routing protocols perform very basic security related functions which are not sufficient to protect the network. In this paper, a secure and fair cluster head selection protocol (SFCP) is proposed which integrates security factors into the clustering approach for achieving attacker identification and classification. Byzantine agreement based cooperative technique is used for attacker identification and classification to make the network more attack resistant. SFCP used to solve this issue by making the nodes that are totally surrounded by malicious neighbors adjust dynamically their belief and disbelief thresholds. The proposed protocol selects the secure and energy efficient cluster head which acts as a local detector without imposing overhead to the clustering performance. SFCP is simulated in network simulator 2 and compared with two protocols including AODV and CBRP.

A robust certification service for highly dynamic MANET in emergency tasks

DEFF Research Database (Denmark)

Ge, M; Lam, K Y; Gollmann, Dieter

2009-01-01

In emergency tasks, cross-agency operations being carried out in disaster-hit areas require some supporting communication system for command and control. Mobile Ad hoc Network (MANET) is a very suitable way to meet such communication requirements since it can function without any pre......-installed communication infrastructure. Owing to potential threats in the field environment and the unique features of MANET (e.g. the open nature of wireless links and the absence of security infrastructure), security of communications over MANET is a serious issue that is typically addressed by asymmetric cryptographic...... public keys in our scenario. For issuance and/or revocation of mission-specific certificate, a Mission-specific Certificate Authority (MCA), which consists of a collection of server nodes to operate the threshold cryptographic scheme, is proposed. Furthermore, to cater for the occurrence of network...

Analisis Unjuk Kerja Aplikasi VoIP Call Android di Jaringan MANET [Performance Analysis of VoIP Call Application Android in MANET (Mobile Ad Hoc Network

Directory of Open Access Journals (Sweden)

Ryan Ari Setyawan

2015-06-01

Full Text Available Penelitian ini bertujuan menganalisis kinerja aplikasi  VoIP call android di jaringan MANET (mobile ad hoc network.  Hasil pengujian menunjukan bahwa aplikasi VoIP call android dapat digunakan di jaringan MANET. Delay yang dihasilkan paling besar di pengujian indoor dengan jarak 11-15 meter yakni sebesar 0,014624811 seconds. Packet loss yang dihasilkan pada range 1%-2% sedangkan standar packet loss yang ditetapkan oleh CISCO untuk layanan aplikasi VoIP adalah < 5%. Jitter yang dihasilkan yakni antara 0,01-0,06 seconds sedangkan standar yang ditetapkan oleh CISCO adalah ≤ 30 ms atau 0,03 seconds. Throughput yang dihasilkan pada proses pengujian yakni antar 161 kbps-481 kbps. *****This study aims to analyze the performance of VOIP call android application in the MANET (mobile ad hoc network. The results showed that VoIP applications could be implemented in MANET network. The highest  delay is produced in indoor testing  with distance of 11-15 meters,  which is equal to 0.014624811 seconds. Packet loss is generated in the range of 1% -2%, while packet loss standards set by Cisco for VoIP application services are <5%. The jitter is between 0.01 to 0.06 seconds, while the standard set by CISCO is ≤ 30 ms or 0.03 seconds. Throughput generated in the testing process is between 161 kbps-481 kbps.

Mobility and Cooperation to Thwart Node Capture Attacks in MANETs

Directory of Open Access Journals (Sweden)

Mauro Conti

2009-01-01

Full Text Available The nature of mobile ad hoc networks (MANETs, often unattended, makes this type of networks subject to some unique security issues. In particular, one of the most vexing problem for MANETs security is the node capture attack: an adversary can capture a node from the network eventually acquiring all the cryptographic material stored in it. Further, the captured node can be reprogrammed by the adversary and redeployed in the network in order to perform malicious activities. In this paper, we address the node capture attack in MANETs. We start from the intuition that mobility, in conjunction with a reduced amount of local cooperation, helps computing effectively and with a limited resource usage network global security properties. Then, we develop this intuition and use it to design a mechanism to detect the node capture attack. We support our proposal with a wide set of experiments showing that mobile networks can leverage mobility to compute global security properties, like node capture detection, with a small overhead.

Intelligent QoS routing algorithm based on improved AODV protocol for Ad Hoc networks

Science.gov (United States)

Huibin, Liu; Jun, Zhang

2016-04-01

Mobile Ad Hoc Networks were playing an increasingly important part in disaster reliefs, military battlefields and scientific explorations. However, networks routing difficulties are more and more outstanding due to inherent structures. This paper proposed an improved cuckoo searching-based Ad hoc On-Demand Distance Vector Routing protocol (CSAODV). It elaborately designs the calculation methods of optimal routing algorithm used by protocol and transmission mechanism of communication-package. In calculation of optimal routing algorithm by CS Algorithm, by increasing QoS constraint, the found optimal routing algorithm can conform to the requirements of specified bandwidth and time delay, and a certain balance can be obtained among computation spending, bandwidth and time delay. Take advantage of NS2 simulation software to take performance test on protocol in three circumstances and validate the feasibility and validity of CSAODV protocol. In results, CSAODV routing protocol is more adapt to the change of network topological structure than AODV protocol, which improves package delivery fraction of protocol effectively, reduce the transmission time delay of network, reduce the extra burden to network brought by controlling information, and improve the routing efficiency of network.

Preventing the impact of selfish behavior under MANET using ...

Indian Academy of Sciences (India)

K Rama Abirami

2018-04-13

Apr 13, 2018 ... On Demand Distance Vector (AODV) routing protocol and an extensive analysis on the performance of the proposed .... flexible or adaptable to network dynamics. A secure ... change credit value, (v) did not pay attention to the fairness issue in .... the simulation, the wireless channel capacity of mobile.

A Novel Load Balancing Scheme for Multipath Routing Protocol in MANET

Directory of Open Access Journals (Sweden)

Kokilamani Mounagurusamy

2016-09-01

Full Text Available The recent advancements in information and communication technology create a great demand for multipath routing protocols. In MANET, nodes can be arbitrarily located and can move freely at any given time. The topology of MANET can change rapidly and unpredictably. Because wireless link capacities are usually limited, congestion is possible in MANETs. Hence, balancing the load in a MANET is important since nodes with high load will deplete their batteries quickly, thereby increasing the probability of disconnecting or partitioning the network. To overcome these, the multipath protocol should be aware of load at route discovery phase. The main objective of the proposed article is to balance the load on a node and to extend the lifetime of the node due to the congestion, energy depletion and link failures. This article describes a novel load and congestion aware scheme called Path Efficient Ad-hoc On-demand Multipath Distance Vector (PE-AOMDV protocol to increase the performance of routing process in MANET in terms of congestion, end-to-end delay and load balancing. A new threshold value and a counter variable are introduced to limit the number of communication paths passing over a node in route discovery phase. For every new request the counter variable is incremented by one and the threshold value is compared to see whether the maximum number of connections has been reached or not. The proposed method is network simulator ns-2 and it is found that there is a significant improvement in the proposed scheme. It reduces the energy consumption, average end-to-end delay and normalized routing overhead. Also the proposed scheme increases packet delivery ratio, throughput and minimizes routing overheads.

Integrating a Trust Framework with a Distributed Certificate Validation Scheme for MANETs

Directory of Open Access Journals (Sweden)

Marias Giannis F

2006-01-01

Full Text Available Many trust establishment solutions in mobile ad hoc networks (MANETs rely on public key certificates. Therefore, they should be accompanied by an efficient mechanism for certificate revocation and validation. Ad hoc distributed OCSP for trust (ADOPT is a lightweight, distributed, on-demand scheme based on cached OCSP responses, which provides certificate status information to the nodes of a MANET. In this paper we discuss the ADOPT scheme and issues on its deployment over MANETs. We present some possible threats to ADOPT and suggest the use of a trust assessment and establishment framework, named ad hoc trust framework (ATF, to support ADOPT's robustness and efficiency. ADOPT is deployed as a trust-aware application that provides feedback to ATF, which calculates the trustworthiness of the peer nodes' functions and helps ADOPT to improve its performance by rapidly locating valid certificate status information. Moreover, we introduce the TrustSpan algorithm to reduce the overhead that ATF produces, and the TrustPath algorithm to identify and use trusted routes for propagating sensitive information, such as third parties' accusations. Simulation results show that ATF adds limited overhead compared to its efficiency in detecting and isolating malicious and selfish nodes. ADOPT's reliability is increased, since it can rapidly locate a legitimate response by using information provided by ATF.

Review paper of gateway selection schemes for MANET of NEMO (MANEMO)

International Nuclear Information System (INIS)

Mahmood, Z; Hashim, A; Khalifa, O; Anwar, F; Hameed, S

2013-01-01

The fast growth of Internet applications brings with it new challenges for researchers to provide new solutions that guarantee better Internet access for mobile hosts and networks. The globally reachable, Home-Agent based, infrastructure Network Mobility (NEMO) and the local, multi-hop, and infrastructure-less Mobile Ad hoc Network (MANET) developed by Internet Engineering Task Force (IETF) support different topologies of the mobile networks. A new architecture was proposed by combining both topologies to obtain Mobile Ad Hoc NEMO (MANEMO). However, the integration of NEMO and MANET introduces many challenges such as network loops, sub-optimal route, redundant tunnel problem, absence of communication without Home Agent reachability, and exit router selection when multiple Exit Routers to the Internet exist. This paper aims to review the different proposed models that could be used to implement the gateway selection mechanism and it highlights the strengths as well as the limitations of these approaches

Deployment of SIP in MANET: challenges and circumvention

Directory of Open Access Journals (Sweden)

Abdelhamid Salma R.

2017-01-01

Full Text Available The immense growth in wireless network applications has encouraged the researchers to enhance and propose new approaches that facilitate the deployment of the widely used services, protocols, and applications of the wired networking area in the wireless networks. Among which, the Session Initiation Protocol (SIP is a signaling protocol that allows the establishment of multimedia sessions and calls between different parties. SIP functionality totally depends on a centralized infrastructure, and complexity arises when deploying such a protocol in a special type of wireless networks, namely Mobile Ad-hoc Networks (MANET, due to the absence of a centralized infrastructure, and the dynamic topology of the later. This paper highlights the the challenges arising when deploying SIP in MANETs and presents an overview of different proposed approaches to overcome these challenges.

A recommender system for team formation in MANET

Directory of Open Access Journals (Sweden)

Waleed M. Al-Adrousy

2015-04-01

Full Text Available Mobile social networking is a new trend for social networking that enables users with similar interests to connect together through mobile devices. Therefore, it possesses the same features of a social network with added support to the features of a Mobile Ad-hoc Network (MANET in terms of limited computing power, limited coverage, and intermittent connectivity. One of the most important features in social networks is Team Formation. Team Formation aims to assemble a set of users with a set of skills required for a certain task. The team formation is a special type of recommendation which is important to enable cooperative work among users. Team formation is challenging since users’ interaction time is limited in MANET. The main objective of this paper is to introduce a peer-to-peer team formation technique based on zone routing protocol (ZRP. A comparison was made with Flooding and Adaptive Location Aided Mobile Ad Hoc Network Routing (ALARM techniques. The suggested technique achieves fast successful recommendations within the limited mobile resources and reduces exchanged messages. The suggested technique has fast response time, small required buffering and low power consumption. The testing results show better performance of the suggested technique compared to flooding and ALARM technique.

The photographic subversion: Benjamin, Manet and Art(istic reproduction

Directory of Open Access Journals (Sweden)

Lauren Weingarden

2006-12-01

Full Text Available Besides referring to museum masterpieces in his 1863 paintings Le déjeuner sur l’herbe and Olympia, Édouard Manet used photography, of both academic and pornographic models, new genres of commercial photography that emerged during the early 1850s. I argue that Manet deliberately conflated fine art reproductions and mass media products, a practice that invites discussion in the light of Walter Benjamin’s “The Work of Art in the Age of Its Technological Reproducibility”. Since both engaged in a dialogue with Charles Baudelaire’s writings on art, culture, and photography, these writings provide a framework for discerning modernist paradoxes inherent in Manet’s and Benjamin’s critical interpretations of popular and material culture.

MANETS and Internet of Things: The Development of a Data Routing Algorithm

Directory of Open Access Journals (Sweden)

I. A. Alameri

2018-02-01

Full Text Available Internet of things (IoT, is an innovative technology which allows the connection of physical things with the digital world through the use of heterogeneous networks and communication technologies. IoT in smart environments interacts with wireless sensor network (WSN and mobile ad‐hoc network (MANET, becoming even more attractive and economically successful. Interaction between wireless sensor and mobile ad‐hoc networks with the internet of things allows the creation of a new MANET‐IoT systems and IT‐based networks. Such systems give the user greater mobility and reduce costs. At the same time new challenging issues are opened in networking aspects. In this work, author proposed a routing solution for the IoT system using a combination of MANET protocols and WSN routing principles. The presented results of solution's investigation provide an effective approach to efficient energy consumption in the global MANET‐IoT system. That is a step forward to a reliable provision of services over global future internet infrastructure.

An Efficient Method for Detecting Misbehaving Zone Manager in MANET

Science.gov (United States)

Rafsanjani, Marjan Kuchaki; Pakzad, Farzaneh; Asadinia, Sanaz

In recent years, one of the wireless technologies increased tremendously is mobile ad hoc networks (MANETs) in which mobile nodes organize themselves without the help of any predefined infrastructure. MANETs are highly vulnerable to attack due to the open medium, dynamically changing network topology, cooperative algorithms, lack of centralized monitoring, management point and lack of a clear defense line. In this paper, we report our progress in developing intrusion detection (ID) capabilities for MANET. In our proposed scheme, the network with distributed hierarchical architecture is partitioned into zones, so that in each of them there is one zone manager. The zone manager is responsible for monitoring the cluster heads in its zone and cluster heads are in charge of monitoring their members. However, the most important problem is how the trustworthiness of the zone manager can be recognized. So, we propose a scheme in which "honest neighbors" of zone manager specify the validation of their zone manager. These honest neighbors prevent false accusations and also allow manager if it is wrongly misbehaving. However, if the manger repeats its misbehavior, then it will lose its management degree. Therefore, our scheme will be improved intrusion detection and also provide a more reliable network.

HARDWARE IMPLEMENTATION OF SECURE AODV FOR WIRELESS SENSOR NETWORKS

Directory of Open Access Journals (Sweden)

S. Sharmila

2010-12-01

Full Text Available Wireless Sensor Networks are extremely vulnerable to any kind of routing attacks due to several factors such as wireless transmission and resource-constrained nodes. In this respect, securing the packets is of great importance when designing the infrastructure and protocols of sensor networks. This paper describes the hardware architecture of secure routing for wireless sensor networks. The routing path is selected using Ad-hoc on demand distance vector routing protocol (AODV. The data packets are converted into digest using hash functions. The functionality of the proposed method is modeled using Verilog HDL in MODELSIM simulator and the performance is compared with various target devices. The results show that the data packets are secured and defend against the routing attacks with minimum energy consumption.

Selective Route Based on SNR with Cross-Layer Scheme in Wireless Ad Hoc Network

Directory of Open Access Journals (Sweden)

Istikmal

2017-01-01

Full Text Available In this study, we developed network and throughput formulation models and proposed new method of the routing protocol algorithm with a cross-layer scheme based on signal-to-noise ratio (SNR. This method is an enhancement of routing protocol ad hoc on-demand distance vector (AODV. This proposed scheme uses selective route based on the SNR threshold in the reverse route mechanism. We developed AODV SNR-selective route (AODV SNR-SR for a mechanism better than AODV SNR, that is, the routing protocol that used average or sum of path SNR, and also better than AODV which is hop-count-based. We also used selective reverse route based on SNR mechanism, replacing the earlier method to avoid routing overhead. The simulation results show that AODV SNR-SR outperforms AODV SNR and AODV in terms of throughput, end-to-end delay, and routing overhead. This proposed method is expected to support Device-to-Device (D2D communications that are concerned with the quality of the channel awareness in the development of the future Fifth Generation (5G.

Nitride and carbide thin films as hydrogen permeation barrier on Manet steel

International Nuclear Information System (INIS)

Benamati, G.; Checchetto, R.; Bonelli, M.; Gratton, L.M.; Guzman, L.; Miotello, A.; Terlain, A.

1995-01-01

TiC / TiN bilayers, ∼ 1.2 μm thick, were deposited on Manet II steel by the ion beam assisted deposition technique to investigate the possible use of this ceramic coating as hydrogen barrier. Hydrogen permeation experiments in the temperature range 470-570 K showed indeed that this coating is a very efficient barrier to the hydrogen permeation being able to reduce the hydrogen flux up to two order of magnitude with respect to the uncoated steel. Preliminary compatibility tests between coated Manet II and Pb-17Li showed no attack of Pb-17Li to the steel. (orig.)

Building Realistic Mobility Models for Mobile Ad Hoc Networks

Directory of Open Access Journals (Sweden)

Adrian Pullin

2018-04-01

Full Text Available A mobile ad hoc network (MANET is a self-configuring wireless network in which each node could act as a router, as well as a data source or sink. Its application areas include battlefields and vehicular and disaster areas. Many techniques applied to infrastructure-based networks are less effective in MANETs, with routing being a particular challenge. This paper presents a rigorous study into simulation techniques for evaluating routing solutions for MANETs with the aim of producing more realistic simulation models and thereby, more accurate protocol evaluations. MANET simulations require models that reflect the world in which the MANET is to operate. Much of the published research uses movement models, such as the random waypoint (RWP model, with arbitrary world sizes and node counts. This paper presents a technique for developing more realistic simulation models to test and evaluate MANET protocols. The technique is animation, which is applied to a realistic scenario to produce a model that accurately reflects the size and shape of the world, node count, movement patterns, and time period over which the MANET may operate. The animation technique has been used to develop a battlefield model based on established military tactics. Trace data has been used to build a model of maritime movements in the Irish Sea. Similar world models have been built using the random waypoint movement model for comparison. All models have been built using the ns-2 simulator. These models have been used to compare the performance of three routing protocols: dynamic source routing (DSR, destination-sequenced distance-vector routing (DSDV, and ad hoc n-demand distance vector routing (AODV. The findings reveal that protocol performance is dependent on the model used. In particular, it is shown that RWP models do not reflect the performance of these protocols under realistic circumstances, and protocol selection is subject to the scenario to which it is applied. To

Nitride and carbide thin films as hydrogen permeation barrier on MANET steel

International Nuclear Information System (INIS)

Benamati, G.

1994-01-01

TiC/TiN bilayers, - 1.2 μm thick, were deposited on Manet II steel by the ion beam assisted deposition technique to investigate the possible use of this ceramic coating as hydrogen barrier. Hydrogen permeation experiments in the temperature range 470-570 K showed indeed that this coating is a very efficient barrier to the hydrogen permeation being able to reduce the hydrogen flux up to two order of magnitude with respect to the uncoated steel. Preliminary compatibility tests between coated Manet II and Pb-17Li showed no attack of Pb-17Li to the steel. (author) 8 refs.; 2 figs.; 1 tab

An efficient collaborative approach for black hole attack discovery and mitigating its impact in manet

Science.gov (United States)

Devipriya, K.; Ivy, B. Persis Urbana; Prabha, D.

2018-04-01

A mobile ad hoc network (MANET) is an assemblage of nodes composed of mobile devices coupled in various ways wirelessly which do not have any central administration. Each node in MANET cooperates in forwarding packets in the network. This type of collaboration incurs high cost but there exits nodes that declines to cooperate leading to selfish conduct of nodes which effects overall network performance. To discover the attacks caused by such nodes, a renowned mechanism using watchdog can be deployed. In infrastructure less network attack detection and reaction and high false positives, false negatives initiating black hole attack becomes major issue in watchdog. This paper put forward a collaborative approach for identifying such attacks in MANET. Through abstract analysis and extensive simulation of this approach, the detection time of misbehaved nodes is reduced and substantial enhancement in overhead and throughput is witnessed.

: Manet's pictorial production : a forgetful recollection

OpenAIRE

Massonnaud , Dominique

2000-01-01

International audience; Manet's pictorial production is both a necessary step for the discourse about what is commonly called "modernity" -as well as the discourse coming from "modernity"-, and a blind spot for critical analysis: his work seems to be left out of, or buried under, contemporary commentaries that appear to miss the point of what they address. Baudelaire, Huysmans, Zola at the end of his life, or critics of that time that are now forgotten, all seem not to actually grasp the esse...

Framework for developing realistic MANET simulations

CSIR Research Space (South Africa)

Burke, ID

2010-04-01

Full Text Available : Proceedings of the second ACM international workshop on Principles of mobile computing. Toulouse, France, 2002. ACM. Chin, K.-W., Judge, J., Williams, A. & Kermode, R., 2002. Implementation experience with MANET routing protocols. SIGCOMM Comput. Commun... & computing. Long Beach, CA, USA, 2001. ACM. Fall, K. & Varadhan, K., 2003. NS-Manual. [PDF] Available at: http://www.isi.edu/nsnam/ns/doc/ns_doc.pdf . Garrido, P.P., Malumbres, M.P. & Calafate, C.T., 2008. ns-2 vs. OPNET: a comparative study of the IEEE...

Exponential Reliability Coefficient based Reputation Mechanism for isolating selfish nodes in MANETs

Directory of Open Access Journals (Sweden)

J. Sengathir

2015-07-01

Full Text Available In mobile ad hoc networks, cooperation among active mobile nodes is considered to play a vital role in reliable transmission of data. But, the selfish mobile nodes present in an ad hoc environment refuse to forward neighbouring nodes’ packet for conserving its own energy. This intentional selfish behaviour drastically reduces the degree of cooperation maintained between the mobile nodes. Hence, a need arises for devising an effective mechanism which incorporates both energy efficiency and reputation into account for mitigating selfish behaviour in MANETs. In this paper, we propose an Exponential Reliability Coefficient based reputation Mechanism (ERCRM which isolates the selfish nodes from the routing path based on Exponential Reliability Coefficient (ExRC. This reliability coefficient manipulated through exponential failure rate based on moving average method highlights the most recent past behaviour of the mobile nodes for quantifying its genuineness. From the simulation results, it is evident that, the proposed ERCRM approach outperforms the existing Packet Conservation Monitoring Algorithm (PCMA and Spilt Half Reliability Coefficient based Mathematical Model (SHRCM in terms of performance evaluation metrics such as packet delivery ratio, throughput, total overhead and control overhead. Further, this ERCRM mechanism has a successful rate of 28% in isolating the selfish nodes from the routing path. Furthermore, it also aids in framing the exponential threshold point of detection as 0.4, where a maximum number of selfish nodes are identified when compared to the existing models available in the literature.

Manet: A reliable Network in Disaster Areas. | Onwuka | Journal of ...

African Journals Online (AJOL)

This paper describes a communication network that is appropriate, suitable and reliable in any disaster: - Mobile Ad hoc Network (MANET). A mobile ad hoc network is formed dynamically by an autonomous system of mobile nodes that are connected via wireless links without using the existing network infrastructure or ...

Thermal and isothermal low cycle fatigue of MANET I and II

International Nuclear Information System (INIS)

Petersen, C.; Schmitt, R.; Garnier, D.

1996-01-01

Structural components of a DEMO-blanket are subjected during service to alternating thermal and mechanical stresses as a consequence of the pulsed reactor operation. Of particular concern is the fatigue endurance of martensitic steels like MANET under cyclic strains and stresses produced by these temperature changes. In order to design such structures, operating under combined mechanical and thermal cycling, fatigue life has to be calculated with reasonable accuracy. This paper proposes a description of thermal and isothermal mechanical low-cycle fatigue of MANET I and II steels using a single damage model, including plastic strain, temperature and strain rate as variables. This model presents notable advantages for the designer. As it corresponds to a single and continuous 'fatigue strength surface', it enables a reliable interpolation to be made throughout the studied domain of strains and temperatures, and allows for a reasonable extrapolation out of this domain, provided that no different metallurgical phenomena occur. (orig.)

RESILIENT SCHEME AGAINST REDUCTION OF QUALITY (ROQ DISTRIBUTED DENIAL OF SERVICE ATTACK IN MANET

Directory of Open Access Journals (Sweden)

S.A. Arunmozhi

2011-09-01

Full Text Available Defending against denial-of-service attacks (DoS in a mobile ad hoc network (MANET is challenging because of the dynamic network topology. Security primitives must be dynamically adjusted to cope with the network. The Reduction-of-Quality (RoQ Distributed Denial of Service (DDoS attack is one which throttles the tcp throughput heavily and reduces the quality-of-service (QoS to end systems gradually rather than refusing the clients from the services completely. Supporting QoS in MANET is a challenging task, particularly in the presence of malicious users. In this paper, we propose a DoS resilient technique that uses a flow table to detect the attackers. The proposed defense mechanism identifies the attackers based on the congestion bit notification and asks the sending node to reduce the sending rate. Once the attackers are identified, all the packets from those nodes will be blocked. The throughput and delay performance of TCP or UDP flows are very sensitive to such RoQ attacks. Through extensive ns2 network simulations, we demonstrate the achievement of high throughput and low delay for a network under the RoQ attack.

Energy Efficient Probabilistic Broadcasting for Mobile Ad-Hoc Network

Science.gov (United States)

Kumar, Sumit; Mehfuz, Shabana

2017-06-01

In mobile ad-hoc network (MANETs) flooding method is used for broadcasting route request (RREQ) packet from one node to another node for route discovery. This is the simplest method of broadcasting of RREQ packets but it often results in broadcast storm problem, originating collisions and congestion of packets in the network. A probabilistic broadcasting is one of the widely used broadcasting scheme for route discovery in MANETs and provides solution for broadcasting storm problem. But it does not consider limited energy of the battery of the nodes. In this paper, a new energy efficient probabilistic broadcasting (EEPB) is proposed in which probability of broadcasting RREQs is calculated with respect to remaining energy of nodes. The analysis of simulation results clearly indicate that an EEPB route discovery scheme in ad-hoc on demand distance vector (AODV) can increase the network lifetime with a decrease in the average power consumption and RREQ packet overhead. It also decreases the number of dropped packets in the network, in comparison to other EEPB schemes like energy constraint gossip (ECG), energy aware gossip (EAG), energy based gossip (EBG) and network lifetime through energy efficient broadcast gossip (NEBG).

AD HOC Networks for the Autonomous Car

Science.gov (United States)

Ron, Davidescu; Negrus, Eugen

2017-10-01

The future of the vehicle is made of cars, roads and infrastructures connected in a two way automated communication in a holistic system. It is a mandatory to use Encryption to maintain Confidentiality, Integrity and Availability in an ad hoc vehicle network. Vehicle to Vehicle communication, requires multichannel interaction between mobile, moving and changing parties to insure the full benefit from data sharing and real time decision making, a network of such users referred as mobile ad hoc network (MANET), however as ad hoc networks were not implemented in such a scale, it is not clear what is the best method and protocol to apply. Furthermore the visibility of secure preferred asymmetric encrypted ad hoc networks in a real time environment of dense moving autonomous vehicles has to be demonstrated, In order to evaluate the performance of Ad Hoc networks in changing conditions a simulation of multiple protocols was performed on large number of mobile nodes. The following common routing protocols were tested, DSDV is a proactive protocol, every mobile station maintains a routing table with all available destinations, DSR is a reactive routing protocol which allows nodes in the MANET to dynamically discover a source route across multiple network hops, AODV is a reactive routing protocol Instead of being proactive. It minimizes the number of broadcasts by creating routes based on demand, SAODV is a secure version of AODV, requires heavyweight asymmetric cryptographic, ARIANDE is a routing protocol that relies on highly efficient symmetric cryptography the concept is primarily based on DSR. A methodical evolution was performed in a various density of transportation, based on known communication bench mark parameters including, Throughput Vs. time, Routing Load per packets and bytes. Out of the none encrypted protocols, It is clear that in terms of performance of throughput and routing load DSR protocol has a clear advantage the high node number mode. The encrypted

Comparison of MANET routing protocols using a scaled indoor wireless grid

CSIR Research Space (South Africa)

Johnson, DL

2008-04-01

Full Text Available accumulation feature of Dynamic Source Routing (DSR) by adding the accumulated route, back to the source, to the Route Request packet. It retains the destination sequence number feature of AODV but HELLO packets are an optional feature and are normally left... than the inbound traffic as the routing algorithm makes a decision to rebroadcast the packet or not and Figure 20 confirms this. DYMO shows the least amount of routing traffic due to its lack of HELLO packets. This is also due to no further...

Effect of 3 Key Factors on Average End to End Delay and Jitter in MANET

Directory of Open Access Journals (Sweden)

Saqib Hakak

2015-01-01

Full Text Available A mobile ad-hoc network (MANET is a self-configuring infrastructure-less network of mobile devices connected by wireless links where each node or mobile device is independent to move in any desired direction and thus the links keep moving from one node to another. In such a network, the mobile nodes are equipped with CSMA/CA (carrier sense multiple access with collision avoidance transceivers and communicate with each other via radio. In MANETs, routing is considered one of the most difficult and challenging tasks. Because of this, most studies on MANETs have focused on comparing protocols under varying network conditions. But to the best of our knowledge no one has studied the effect of other factors on network performance indicators like throughput, jitter and so on, revealing how much influence a particular factor or group of factors has on each network performance indicator. Thus, in this study the effects of three key factors, i.e. routing protocol, packet size and DSSS rate, were evaluated on key network performance metrics, i.e. average delay and average jitter, as these parameters are crucial for network performance and directly affect the buffering requirements for all video devices and downstream networks.

De Manet a Yves Saint-Laurent: uma análise semiótica

Directory of Open Access Journals (Sweden)

Christiane Paula Godinho Santarelli

2008-09-01

Full Text Available A proposta deste artigo é fazer uma análise semiótica, com base na teoria greimasiana, da pintura original de Manet Le déjeuner sur l’herbe e de sua recriação para o anúncio da marca Yves Saint-Laurent. Os aspectos analisados nos dois “textos” são: os sistemas de valores, a estrutura narrativa, a estrutura de poder, os objetos de valor e a semântica profunda. A comparação dos dois discursos tem como objetivo atentar para as contradições no suposto discurso libertador da publicidade de Yves Saint-Laurent, que pode estar presente na publicidade de outras marcas. Palavras-chave: Publicidade; semiótica; arte; moda. ABSTRACT The purpose of this article is to offer a semiotical analysis of the original painting of Manet Le déjeuner sur l’herbe and of its recreation in an advertisement for the brand Yves Saint-Laurent. The aspects analyzed in the two “texts” are: the systems of enclosed values, the narrative structure, the power structure, the objects of value and deep semantics. The comparison between the two forms of speech aims to highlight the contradictions in the alleged liberating speech of the Yves Saint-Laurent advertisement, which may be present in advertising pieces from other brands. Keywords: Advertising; semiotics; art; fashion.

Clair de lune sur le port de Boulogne: enquête sur un tableau de Manet, traduction d'un article de Donald W. Olson

Science.gov (United States)

Borg, Janet

2016-10-01

The 19th-century artist Edouard Manet created a spectacular nocturnal painting showing a full Moon over the harbor of Boulogne. Art historians have dated this work to either 1868 or 1869. Calculations of lunar phases, 19th-century maps and photographs of Boulogne harbor, the correspondence of the artist, and other clues allow us to determine a date and precise time when Manet observed this moonlit scene.

Unmanned Aerial ad Hoc Networks: Simulation-Based Evaluation of Entity Mobility Models’ Impact on Routing Performance

Directory of Open Access Journals (Sweden)

Jean-Daniel Medjo Me Biomo

2015-06-01

Full Text Available An unmanned aerial ad hoc network (UAANET is a special type of mobile ad hoc network (MANET. For these networks, researchers rely mostly on simulations to evaluate their proposed networking protocols. Hence, it is of great importance that the simulation environment of a UAANET replicates as much as possible the reality of UAVs. One major component of that environment is the movement pattern of the UAVs. This means that the mobility model used in simulations has to be thoroughly understood in terms of its impact on the performance of the network. In this paper, we investigate how mobility models affect the performance of UAANET in simulations in order to come up with conclusions/recommendations that provide a benchmark for future UAANET simulations. To that end, we first propose a few metrics to evaluate the mobility models. Then, we present five random entity mobility models that allow nodes to move almost freely and independently from one another and evaluate four carefully-chosen MANET/UAANET routing protocols: ad hoc on-demand distance vector (AODV, optimized link state routing (OLSR, reactive-geographic hybrid routing (RGR and geographic routing protocol (GRP. In addition, flooding is also evaluated. The results show a wide variation of the protocol performance over different mobility models. These performance differences can be explained by the mobility model characteristics, and we discuss these effects. The results of our analysis show that: (i the enhanced Gauss–Markov (EGM mobility model is best suited for UAANET; (ii OLSR, a table-driven proactive routing protocol, and GRP, a position-based geographic protocol, are the protocols most sensitive to the change of mobility models; (iii RGR, a reactive-geographic hybrid routing protocol, is best suited for UAANET.

Provisioning of adaptability to variable topologies for routing schemes in MANETs

DEFF Research Database (Denmark)

Jiang, Shengming; Liu, Yaoda; Jiang, Yuming

2004-01-01

.g., low, medium, and high mobility) have been proposed in the,literature. However, since a mobile node should not be limited to operate in a particular MANET assumed by-a routing scheme, an important issue is how to enable, a mobile node to achieve routing performance as high as possible when it roams...... in the dynamic source routing protocol to provide the adaptability to variable topologies caused by mobility through computer simulation in NS-2....

MANETS and Internet of Things: The Development of a Data Routing Algorithm

OpenAIRE

Alameri, I. A.

2018-01-01

Internet of things (IoT), is an innovative technology which allows the connection of physical things with the digital world through the use of heterogeneous networks and communication technologies. IoT in smart environments interacts with wireless sensor network (WSN) and mobile ad‐hoc network (MANET), becoming even more attractive and economically successful. Interaction between wireless sensor and mobile ad‐hoc networks with the internet of things allows the creation of a new MANET‐IoT syst...

Notas sobre o escândalo e o cinismo de Manet

Directory of Open Access Journals (Sweden)

Tereza Calomeni

2013-10-01

Full Text Available Em 1971, Foucault profere, em Túnis, uma conferência sobre a pintura de Manet. Em 1984, em A coragem da verdade, último curso oferecido no Collège de France, analisando o cinismo como expressão da parresia, novamente se refere ao pintor ao relacionar arte moderna e cinismo. A partir dos dois textos, o artigo reflete sobre o escândalo de Olympia, uma das treze telas examinadas na conferência, e a relação, estabelecida no curso, entre arte moderna e cinismo.

The afterlife of antiquity and modern art: Aby Warburg on Manet

Directory of Open Access Journals (Sweden)

Dimitrios Latsis

2015-12-01

Full Text Available Aby Warburg’s manuscript on Édouard Manet – unpublished during his lifetime and presented here for the first time in English – constitutes one of his rare, substantial commentaries on nineteenth century art. Using “Le Déjeuner sur l’herbe” as a departure point, Warburg proceeds from his customary meticulous investigation of the central motif’s “visual archeology,” to a larger reflection on the evolution of the representation of nature in art and the image of antiquity that modernity has created for itself.

Data dissemination in the wild: A testbed for high-mobility MANETs

DEFF Research Database (Denmark)

Vingelmann, Peter; Pedersen, Morten Videbæk; Heide, Janus

2012-01-01

This paper investigates the problem of efficient data dissemination in Mobile Ad hoc NETworks (MANETs) with high mobility. A testbed is presented; which provides a high degree of mobility in experiments. The testbed consists of 10 autonomous robots with mobile phones mounted on them. The mobile...... information, and the goal is to convey that information to all devices. A strategy is proposed that uses UDP broadcast transmissions and random linear network coding to facilitate the efficient exchange of information in the network. An application is introduced that implements this strategy on Nokia phones...

Mobility Model for Self-Organizing and Cooperative MSN and MANET Systems

Directory of Open Access Journals (Sweden)

Andrzej Sikora

2012-03-01

Full Text Available Self-organization mechanisms are used for building scalable systems consisting of a huge number of subsystems. In computer networks, self-organizing is especially important in ad hoc networking. A self-organizing ad hoc network is a collection of wireless devices that collaborate with each other to form a network system that adapts to achieve a goal or goals. Such network is often built from mobile devices that may spontaneously create a network and dynamically adapted to changes in an unknown environment. Mobility pattern is a critical element that influences the performance characteristics of mobile sensor networks (MSN and mobile ad hoc networks (MANET. In this paper, we survey main directions to mobility modeling. We describe a novel algorithm for calculating mobility patterns for mobile devices that is based on a cluster formation and an artificial potential function. Finally, we present the simulation results of its application to a rescue mission planning.

The adherence of aluminide coatings on MANET II stainless steel and their effect on its mechanical properties

International Nuclear Information System (INIS)

Sample, T.; Fenici, P.; Kolbe, H.; Orecchia, L.

1994-01-01

This paper describes the production and testing of two different aluminide coatings on the surface of MANET II stainless steel. The coatings were produced by heat treatment of a pure aluminium layer (∼ 100 μm) which had been deposited by vacuum plasma spray. Series 1 coatings were produced by a single heat treatment (1023 K/2h) while series 2 coatings were produced by two consecutive heat treatments (1348 K/30 min, 1023 K/2h). Series 1 coatings were ∼ 120 μm thick, richer in aluminium and harder than series 2 coatings which formed two layers of ∼ 120 μm each. Due to their softer character, series 2 coatings exhibited a greater resistance to cracking under cyclic testing than series 1 coatings. Tensile tests of coated specimens indicated that the coating procedures did not degrade the mechanical properties of the bulk MANET II. (author) 8 refs.; 3 figs.; 3 tabs

An Analysis Platform for Mobile Ad Hoc Network (MANET) Scenario Execution Log Data

Science.gov (United States)

2016-01-01

these technologies. 4.1 Backend Technologies • Java 1.8 • my-sql-connector- java -5.0.8.jar • Tomcat • VirtualBox • Kali MANET Virtual Machine 4.2...Frontend Technologies • LAMPP 4.3 Database • MySQL Server 5. Database The SEDAP database settings and structure are described in this section...contains all the backend java functionality including the web services, should be placed in the webapps directory inside the Tomcat installation

An Evaluation of Media-Oriented Rate Selection Algorithm for Multimedia Transmission in MANETs

Directory of Open Access Journals (Sweden)

Guionnet Thomas

2005-01-01

Full Text Available We focus on the optimization of real-time multimedia transmission over 802.11-based ad hoc networks. In particular, we propose a simple and efficient cross-layer mechanism that considers both the channel conditions and characteristics of the media for dynamically selecting the transmission mode. This mechanism called media-oriented rate selection algorithm (MORSA targets loss-tolerant applications such as VoD that do not require full reliable transmission. We provide an evaluation of this mechanism for MANETs using simulations with NS and analyze the video quality obtained with a fine-grain scalable video encoder based on a motion-compensated spatiotemporal wavelet transform. Our results show that MORSA achieves up to 4 Mbps increase in throughput and that the routing overhead decreases significantly. Transmission of a sample video flow over an 802.11a wireless channel has been evaluated with MORSA. Important improvement is observed in throughput, latency, and jitter while keeping a good level of video quality.

A Hop-Count Analysis Scheme for Avoiding Wormhole Attacks in MANET

Directory of Open Access Journals (Sweden)

Chi-Sung Laih

2009-06-01

Full Text Available MANET, due to the nature of wireless transmission, has more security issues compared to wired environments. A specific type of attack, the Wormhole attack does not require exploiting any nodes in the network and can interfere with the route establishment process. Instead of detecting wormholes from the role of administrators as in previous methods, we implement a new protocol, MHA, using a hop-count analysis from the viewpoint of users without any special environment assumptions. We also discuss previous works which require the role of administrator and their reliance on impractical assumptions, thus showing the advantages of MHA.

Securing mobile ad hoc networks using danger theory-based artificial immune algorithm.

Science.gov (United States)

Abdelhaq, Maha; Alsaqour, Raed; Abdelhaq, Shawkat

2015-01-01

A mobile ad hoc network (MANET) is a set of mobile, decentralized, and self-organizing nodes that are used in special cases, such as in the military. MANET properties render the environment of this network vulnerable to different types of attacks, including black hole, wormhole and flooding-based attacks. Flooding-based attacks are one of the most dangerous attacks that aim to consume all network resources and thus paralyze the functionality of the whole network. Therefore, the objective of this paper is to investigate the capability of a danger theory-based artificial immune algorithm called the mobile dendritic cell algorithm (MDCA) to detect flooding-based attacks in MANETs. The MDCA applies the dendritic cell algorithm (DCA) to secure the MANET with additional improvements. The MDCA is tested and validated using Qualnet v7.1 simulation tool. This work also introduces a new simulation module for a flooding attack called the resource consumption attack (RCA) using Qualnet v7.1. The results highlight the high efficiency of the MDCA in detecting RCAs in MANETs.

A time-based admission control mechanism for IEEE 802.11 ad Hoc networks

OpenAIRE

Costa, Luís Henrique M. K.; Cerveira, Carlos Rodrigo

2006-01-01

This paper presents a time-based admission control mechanism (TAC) for IEEE 802.11 ad hoc networks. The proposed mechanism was adapted to the QoS AODV routing protocol, which takes the quality of service requirements of the data flow into account in the route discovery process. TAC-AODV estimates the idle time of the physical medium based on the frames listened. The incoming traffic is admitted according to the offered load as well as the intra-flow interference, calculated based on the numbe...

HOP: Achieving Efficient Anonymity in MANETs by Combining HIP, OLSR, and Pseudonyms

Directory of Open Access Journals (Sweden)

Campos Javier

2011-01-01

Full Text Available Offering secure and anonymous communications in mobile ad hoc networking environments is essential to achieve confidence and privacy, thus promoting widespread adoption of this kind of networks. In addition, some minimum performance levels must be achieved for any solution to be practical and become widely adopted. In this paper, we propose and implement HOP, a novel solution based on cryptographic Host Identity Protocol (HIP that offers security and user-level anonymity in MANET environments while maintaining good performance levels. In particular, we introduce enhancements to the authentication process to achieve Host Identity Tag (HIT relationship anonymity, along with source/destination HIT anonymity when combined with multihoming. Afterward we detail how we integrate our improved version of HIP with the OLSR routing protocol to achieve efficient support for pseudonyms. We implemented our proposal in an experimental testbed, and the results obtained show that performance levels achieved are quite good, and that the integration with OLSR is achieved with a low overhead.

A Preemptive Link State Spanning Tree Source Routing Scheme for Opportunistic Data Forwarding in MANET

OpenAIRE

R. Poonkuzhali; M. Y. Sanavullah; A. Sabari

2014-01-01

Opportunistic Data Forwarding (ODF) has drawn much attention in mobile adhoc networking research in recent years. The effectiveness of ODF in MANET depends on a suitable routing protocol which provides a powerful source routing services. PLSR is featured by source routing, loop free and small routing overhead. The update messages in PLSR are integrated into a tree structure and no need to time stamp routing updates which reduces the routing overhead.

A COMPREHENSIVE SURVEY ON DETECTING BLACK HOLE ATTACK IN MOBILE AD-HOC NETWORK (MANET

Directory of Open Access Journals (Sweden)

Pascal Maniriho

2018-01-01

Full Text Available The infrastructure-less nature and mobility of nodes in mobile ad-hoc network (MANET make it to be very susceptible to various attacks. Besides, owing to its flexibility and simplicity, there is no predefined time or permission set for nodes to leave or join the network and each node can act as a client or server.  Nevertheless, securing communication between nodes has become a challenging problem than in other types of network. Attacks in MANET range into different categories. Black hole attack is one of the attacks that has been addressed by many researchers in the recent years. It does occur when a harmful mobile node called black hole becomes a part of the network and tries to use its malicious behaviors by sending fake route reply packets (RREP for any received route request packets (RREQ. When these faked packets arrive to the source node, it does reply to them by sending data packet via the established route. Once the packets are received by the black hole, it drops them before reaching the destination.  Hence, preventing the source node from reaching the intended destination. In this paper, we present an overview of a wide range of techniques suggested in the literature for detecting and preventing black hole attacks in mobile ad hoc network. Additionally, the effect of each approach on the network performance is also presented.

The Inevitability of Sleep: Using Manet's Last Paintings to Envision a Pedagogy of Loss and Mourning

Science.gov (United States)

Otto, Stacy

2013-01-01

In this article, the author offers Manet's last paintings as metaphors for a bygone, psychically healthy conception of loss and mourning, what is called the pre-Freudian, Victorian notion of loss (Otto 2008), which contrasts with the post-Freudian, Modern notion of loss and mourning (Otto 2008). Otto argues this liminal, transitional moment…

BLACK HOLE ATTACK IN AODV & FRIEND FEATURES UNIQUE EXTRACTION TO DESIGN DETECTION ENGINE FOR INTRUSION DETECTION SYSTEM IN MOBILE ADHOC NETWORK

Directory of Open Access Journals (Sweden)

HUSAIN SHAHNAWAZ

2012-10-01

Full Text Available Ad-hoc network is a collection of nodes that are capable to form dynamically a temporary network without the support of any centralized fixed infrastructure. Since there is no central controller to determine the reliable & secure communication paths in Mobile Adhoc Network, each node in the ad hoc network has to rely on each other in order to forward packets, thus highly cooperative nodes are required to ensure that the initiated data transmission process does not fail. In a mobile ad hoc network (MANET where security is a crucial issue and they are forced to rely on the neighbor node, trust plays an important role that could improve the number of successful data transmission. Larger the number of trusted nodes, higher successful data communication process rates could be expected. In this paper, Black Hole attack is applied in the network, statistics are collected to design intrusion detection engine for MANET Intrusion Detection System (IDS. Feature extraction and rule inductions are applied to find out the accuracy of detection engine by using support vector machine. In this paper True Positive generated by the detection engine is very high and this is a novel approach in the area of Mobile Adhoc Intrusion detection system.

Analysis of mechanical effects caused by plasma disruptions in the European breeder out of tube solid breeder blanket design with MANET as structural material

International Nuclear Information System (INIS)

Boccaccini, L.V.; Ruatto, P.

1995-01-01

In this paper we deal with some aspects related to the mechanical behaviour of the European breeder out of tube solid breeder blanket for the DEMO reactor during plasma disruptions. The first aspect regards the properties of the martensitic steel MANET which has been chosen as structural material. MANET is a magnetic material and its fracture toughness properties degrade considerably under irradiation. These two features have been taken into account in the calculation of magentic forces and in the assessment of conditions of unstable crack propagation respectively. As second aspect, a comparison between an electrically segmented and a continuous blanket design has been performed. The analysis reveals lower mechanical stresses for the second design during the DEMO reference disruption and in case of faster disruptions. (orig.)

Energy generation for an ad hoc wireless sensor network-based monitoring system using animal head movement

DEFF Research Database (Denmark)

S. Nadimi, Esmaeil; Blanes-Vidal, Victoria; Jørgensen, Rasmus Nyholm

2011-01-01

are not easily accessible. Therefore, exploring novel sources of energy generation rather than operating electronics only on limited power supplies such as batteries is a major challenge. Monitoring free-ranging animal behavior is an application in which the entities (animals) within the MANET are not readily...... that the amount of energy generated by the vertical neck–head movement of sheep during grazing can be converted to useful electrical power adequate to provide power for operation of wireless sensor nodes on a continuous basis within a MANET-based animal behavior monitoring system.......The supply of energy to electronics is an imperative constraining factor to be considered during the design process of mobile ad hoc wireless sensor networks (MANETs). This influence is especially important when the MANET is deployed unattended or the wireless modules within the MANET...

Robust against route failure using power proficient reliable routing in MANET

Directory of Open Access Journals (Sweden)

M. Malathi

2018-03-01

Full Text Available The aim of this paper was to propose a novel routing protocol for Mobile Adhoc Network communication which reduces the route failure during transmission. The proposed routing protocol uses 3 salient parameters to discover the path which ensure the reliable communication. The quality of the channel, link quality and energy level of the node are the major reasons for unintentional node failure in mobile Adhoc network. So the proposed routing protocol considers these three parameters to select the best forwarder node in the path. The reliable data communication is achieved by transmitting data via path selected by the proposed routing scheme has been proven using network simulator (NS2. Keywords: Channel quality, Link quality, Mobile Adhoc Network (MANET, Residual energy

Performance analysis and implementation of proposed mechanism for detection and prevention of security attacks in routing protocols of vehicular ad-hoc network (VANET

Directory of Open Access Journals (Sweden)

Parul Tyagi

2017-07-01

Full Text Available Next-generation communication networks have become widely popular as ad-hoc networks, broadly categorized as the mobile nodes based on mobile ad-hoc networks (MANET and the vehicular nodes based vehicular ad-hoc networks (VANET. VANET is aimed at maintaining safety to vehicle drivers by begin autonomous communication with the nearby vehicles. Each vehicle in the ad-hoc network performs as an intelligent mobile node characterized by high mobility and formation of dynamic networks. The ad-hoc networks are decentralized dynamic networks that need efficient and secure communication requirements due to the vehicles being persistently in motion. These networks are more susceptible to various attacks like Warm Hole attacks, denial of service attacks and Black Hole Attacks. The paper is a novel attempt to examine and investigate the security features of the routing protocols in VANET, applicability of AODV (Ad hoc On Demand protocol to detect and tackle a particular category of network attacks, known as the Black Hole Attacks. A new algorithm is proposed to enhance the security mechanism of AODV protocol and to introduce a mechanism to detect Black Hole Attacks and to prevent the network from such attacks in which source node stores all route replies in a look up table. This table stores the sequences of all route reply, arranged in ascending order using PUSH and POP operations. The priority is calculated based on sequence number and discard the RREP having presumably very high destination sequence number. The result show that proposed algorithm for detection and prevention of Black Hole Attack increases security in Intelligent Transportation System (ITS and reduces the effect of malicious node in the VANET. NCTUNs simulator is used in this research work.

Fracture toughness of manet II steel

International Nuclear Information System (INIS)

Gboneim, M.M.; Munz, D.

1997-01-01

High fracture toughness was evaluated according to the astm and chromium (9-12) martensitic steels combine high strength and toughness with good corrosion and oxidation resistance in a range of environments, and also show relatively high creep strength at intermediate temperatures. They therefore find applications in, for example, the offshore oil and gas production and chemical industries i pipe work and reaction vessels, and in high temperature steam plant in power generation systems. Recently, the use of these materials in the nuclear field was considered. They are candidates as tubing materials for breeder reactor steam generators and as structural materials for the first wall and blanket in fusion reactors. The effect of ageing on the tensile properties and fracture toughness of a 12 Cr-1 Mo-Nb-v steel, MANET II, was investigated in the present work. Tensile specimens and compact tension (CT) specimens were aged at 550 degree C for 1000 h. The japanese standards. Both microstructure and fracture surface were examined using optical and scanning electron microscopy (SEM). The results showed that ageing did not affect the tensile properties. However, the fracture toughness K Ic and the tearing modules T were reduced due to the ageing treatment. The results were discussed in the light of the chemical composition and the fracture surface morphology. 9 figs., 3 tabs

LITERATURE SURVEY ON EXISTING POWER SAVING ROUTING METHODS AND TECHNIQUES FOR INCREASING NETWORK LIFE TIME IN MANET

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K Mariyappan

2017-06-01

Full Text Available Mobile ad hoc network (MANET is a special type of wireless network in which a collection of wireless mobile devices (called also nodes dynamically forming a temporary network without the need of any pre-existing network infrastructure or centralized administration. Currently, Mobile ad hoc networks (MANETs play a significant role in university campus, advertisement, emergency response, disaster recovery, military use in battle fields, disaster management scenarios, in sensor network, and so on. However, wireless network devices, especially in ad hoc networks, are typically battery-powered. Thus, energy efficiency is a critical issue for battery-powered mobile devices in ad hoc networks. This is due to the fact that failure of node or link allows re-routing and establishing a new path from source to destination which creates extra energy consumption of nodes and sparse network connectivity, leading to a more likelihood occurrences of network partition. Routing based on energy related parameters is one of the important solutions to extend the lifetime of the node and reduce energy consumption of the network. In this paper detail literature survey on existing energy efficient routing method are studied and compared for their performance under different condition. The result has shown that both the broadcast schemes and energy aware metrics have great potential in overcoming the broadcast storm problem associated with flooding. However, the performances of these approaches rely on either the appropriate selection of the broadcast decision parameter or an energy efficient path. In the earlier proposed broadcast methods, the forwarding probability is selected based on fixed probability or number of neighbors regardless of nodes battery capacity whereas in energy aware schemes energy inefficient node could be part of an established path. Therefore, in an attempt to remedy the paucity of research and to address the gaps identified in this area, a study

Performance Analysis of the Enhanced DSR Routing Protocol for the Short Time Disconnected MANET to the OPNET Modeler

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PAPAJ Ján

2013-05-01

Full Text Available Disconnected mobile ad-hoc networks (MANET are very important areas of the research. In this article, the performance analysis of the enhanced dynamic source routing protocol (OPP_DSR is introduced. This modification enables the routing process in the case when there are no connections to other mobile nodes. It also will enable the routing mechanisms when the routes, selected by routing mechanisms, are disconnected for some time. Disconnection can be for a short time and standard routing protocol DSR cannot reflect on this situation.The main idea is based on opportunistic forwarding where the nodes not only forward data but it's stored in the cache during long time. The network parameters throughput, routing load and are analysed.

SERVICE PROVISIONING IN MANETS USING SERVICE PROVIDER’S METRICS

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K. Ponmozhi

2012-09-01

Full Text Available Service discovery technologies are exploited to enable services to advertise their existence in a dynamic way and can be discovered, configured and used by other devices with minimum of manual efforts. Automatic service discovery plays an important role in future network scenarios. Service discovery in distributed environment is difficult that too if the availability information of the services cannot be in a centralized node. The complexity is increased even further in the case of MANETs in which there will not be central intelligence also, the nodes involved may be on the move. The mobility issue leads to the situation of uncertainty about the service availability of the service provider. In this paper we propose a decentralized discovery mechanism. The basic idea is, distributing service information along with the availability metrics to the nodes. The metrics will give us the information to evaluate the goodness of the service provider. Every node will form multi-layered overlays of service providers sorted based on the metrics. When we send a query, each node will identify the service provider from the overlay with the good metric among the available providers (i.e. the one in the first position in the overlay. We define the message structures and methods needed for this proposal. The simulation result shows that in the high mobile environment too we could have a better convergence. We believe that the architecture presented here is a necessary component of any service provision framework.

Using Link Disconnection Entropy Disorder to Detect Fast Moving Nodes in MANETs.

Science.gov (United States)

Alvarez, Carlos F; Palafox, Luis E; Aguilar, Leocundo; Sanchez, Mauricio A; Martinez, Luis G

2016-01-01

Mobile ad-hoc networks (MANETs) are dynamic by nature; this dynamism comes from node mobility, traffic congestion, and other transmission conditions. Metrics to evaluate the effects of those conditions shine a light on node's behavior in an ad-hoc network, helping to identify the node or nodes with better conditions of connection. In this paper, we propose a relative index to evaluate a single node reliability, based on the link disconnection entropy disorder using neighboring nodes as reference. Link disconnection entropy disorder is best used to identify fast moving nodes or nodes with unstable communications, this without the need of specialized sensors such as GPS. Several scenarios were studied to verify the index, measuring the effects of Speed and traffic density on the link disconnection entropy disorder. Packet delivery ratio is associated to the metric detecting a strong relationship, enabling the use of the link disconnection entropy disorder to evaluate the stability of a node to communicate with other nodes. To expand the utilization of the link entropy disorder, we identified nodes with higher speeds in network simulations just by using the link entropy disorder.

Cross-Layer Service Discovery Mechanism for OLSRv2 Mobile Ad Hoc Networks

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M. Isabel Vara

2015-07-01

Full Text Available Service discovery plays an important role in mobile ad hoc networks (MANETs. The lack of central infrastructure, limited resources and high mobility make service discovery a challenging issue for this kind of network. This article proposes a new service discovery mechanism for discovering and advertising services integrated into the Optimized Link State Routing Protocol Version 2 (OLSRv2. In previous studies, we demonstrated the validity of a similar service discovery mechanism integrated into the previous version of OLSR (OLSRv1. In order to advertise services, we have added a new type-length-value structure (TLV to the OLSRv2 protocol, called service discovery message (SDM, according to the Generalized MANET Packet/Message Format defined in Request For Comments (RFC 5444. Each node in the ad hoc network only advertises its own services. The advertisement frequency is a user-configurable parameter, so that it can be modified depending on the user requirements. Each node maintains two service tables, one to store information about its own services and another one to store information about the services it discovers in the network. We present simulation results, that compare our service discovery integrated into OLSRv2 with the one defined for OLSRv1 and with the integration of service discovery in Ad hoc On-demand Distance Vector (AODV protocol, in terms of service discovery ratio, service latency and network overhead.

Cross-Layer Service Discovery Mechanism for OLSRv2 Mobile Ad Hoc Networks.

Science.gov (United States)

Vara, M Isabel; Campo, Celeste

2015-07-20

Service discovery plays an important role in mobile ad hoc networks (MANETs). The lack of central infrastructure, limited resources and high mobility make service discovery a challenging issue for this kind of network. This article proposes a new service discovery mechanism for discovering and advertising services integrated into the Optimized Link State Routing Protocol Version 2 (OLSRv2). In previous studies, we demonstrated the validity of a similar service discovery mechanism integrated into the previous version of OLSR (OLSRv1). In order to advertise services, we have added a new type-length-value structure (TLV) to the OLSRv2 protocol, called service discovery message (SDM), according to the Generalized MANET Packet/Message Format defined in Request For Comments (RFC) 5444. Each node in the ad hoc network only advertises its own services. The advertisement frequency is a user-configurable parameter, so that it can be modified depending on the user requirements. Each node maintains two service tables, one to store information about its own services and another one to store information about the services it discovers in the network. We present simulation results, that compare our service discovery integrated into OLSRv2 with the one defined for OLSRv1 and with the integration of service discovery in Ad hoc On-demand Distance Vector (AODV) protocol, in terms of service discovery ratio, service latency and network overhead.

Analysis of mechanical effects caused by plasma disruptions in the European BOT solid breeder blanket design with MANET as structural material

International Nuclear Information System (INIS)

Boccaccini, L.V.; Ruatto, P.

1994-01-01

The Karlsruhe Nuclear Center is developing, through design and experimental work, a BOT (Breeder Out of Tube) Helium Cooled Solid Breeder Blanket for a DEMO application. One of the crucial problems in the blanket design is to demonstrate the capability of the structure to withstand the mechanical effects of a major plasma disruption as extrapolated to DEMO from the experience of present machines. In this paper the results of the assessment work are presented; the acceptability of the design is discussed on the basis of a stress analysis of the structure under combined thermal and electromagnetic loads. The martensitic steel MANET has been chosen as structural material, because it is able to withstand the high neutron fluence in Demo (70 dpa) without appreciably swelling and has good thermal-mechanical properties - lower thermal expansion and higher strength - in comparison to AISI 316L steel. As far as it concerns the mechanical effects of plasma disruptions, MANET presents two important features which have been carefully investigated in the assessment: the magnetic properties of the material and the degradation of the fracture toughness behavior under irradiation

ANALISIS LAYANAN VOIP PADA JARINGAN MANET DENGAN CODEC YANG BERBEDA

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Randa Oktavada Zein

2016-12-01

Full Text Available Voice Over Internet Protocol (VoIP merupakan layanan bersifat real-time, parameter yang dapat mempengaruhi kulitas layanan seperti delay, jitter dan packet loss. Dalam proses pengkodean sinyal analog menjadi sinyal digital menyebabkan terjadiya delay pada VoIP. Sistem pengcodean ini disebut codec, setiap codec memiliki bitrate yang berbeda pengkodeannya. Pada penelitian ini menggunakan codec G.711, G729 dan codec G.723.1 sebagai perbandingan untuk mengetahui qulity of service (QoS VoIP jika diterapkan pada jaringan MANET. Dengan penambahan aplikasi Hypertext Transfer Protovol (HTTP untuk mendapatkan parameter QoS VoIP dari codec G.711, G.729 dan G.723.1. Hasil yang didapat pada codec G.723.1 lebih baik jika dibandingkan dengan codec g.711 dan G.729 dilihat dari nilai dari parameter QoS seperti delay, jitter dan packet loss. Sesuai standar ITU-T G114 dimana perhitunan teoritis parameter dari codec G.723.1 didapat hasil terendah 7,68 kbps.

Evaluation of mobile ad hoc network reliability using propagation-based link reliability model

International Nuclear Information System (INIS)

Padmavathy, N.; Chaturvedi, Sanjay K.

2013-01-01

A wireless mobile ad hoc network (MANET) is a collection of solely independent nodes (that can move randomly around the area of deployment) making the topology highly dynamic; nodes communicate with each other by forming a single hop/multi-hop network and maintain connectivity in decentralized manner. MANET is modelled using geometric random graphs rather than random graphs because the link existence in MANET is a function of the geometric distance between the nodes and the transmission range of the nodes. Among many factors that contribute to the MANET reliability, the reliability of these networks also depends on the robustness of the link between the mobile nodes of the network. Recently, the reliability of such networks has been evaluated for imperfect nodes (transceivers) with binary model of communication links based on the transmission range of the mobile nodes and the distance between them. However, in reality, the probability of successful communication decreases as the signal strength deteriorates due to noise, fading or interference effects even up to the nodes' transmission range. Hence, in this paper, using a propagation-based link reliability model rather than a binary-model with nodes following a known failure distribution to evaluate the network reliability (2TR m , ATR m and AoTR m ) of MANET through Monte Carlo Simulation is proposed. The method is illustrated with an application and some imperative results are also presented

Characterizing Deficiencies of Path-Based Routing for Wireless Multi-Hop Networks

Science.gov (United States)

2017-05-01

all traffic). In order to avoid the effects of congestion and queue overflows, data rates are set arbitrarily high. For both OLSR and AODV, we test two...Loadng: Towards aodv version 2,” in Vehicular Technology Conference (VTC Fall), 2012 IEEE. IEEE, 2012, pp. 1–5. [11] T. Clausen, A. C. de Verdiere, J

Detection and Prevention of Denial of Service (DoS Attacks in Mobile Ad Hoc Networks using Reputation-based Incentive Schemes

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Mieso, K Denko

2005-08-01

Full Text Available Mobile ad hoc networks (MANETs are dynamic mobile networks that can be formed in the absence of any pre-existing communication infrastructure. In addition to node mobility, a MANET is characterized by limited resources such as bandwidth, battery power, and storage space. The underlying assumption in MANETs is that the intermediate nodes cooperate in forwarding packets. However, this assumption does not hold in commercial and emerging civilian applications. MANETs are vulnerable to Denial of Service (DoS due to their salient characteristics. There is a need to provide an incentive mechanism that can provide cooperation among nodes in the network and improve overall network performance by reducing DoS attacks. In this paper, we propose a reputation-based incentive mechanism for detecting and preventing DoS attacks. DoS attacks committed by selfish and malicious nodes were investigated. Our scheme motivates nodes to cooperate and excludes them from the network only if they fail to do so. We evaluated the performance of our scheme using the packet delivery ratio, the routing and communication overhead, and misbehaving node detection in a discrete event-simulation environment. The results indicate that a reputation-based incentive mechanism can significantly reduce the effect of DoS attacks and improve performance in MANETs.

Soporte de QoS con 802.11e para tráfico heterogéneo en ambientes MANET

OpenAIRE

Murazzo, María Antonia; Rodríguez, Nelson R.; Guevara, Miguel José; Scheffer, María

2014-01-01

Hoy en día existe una gran necesidad de mejorar la calidad de servicio (QoS) ofrecida en redes móviles Ad Hoc (Mobile Ad-Hoc Networks -MANET-) que actualmente sólo ofrecen servicio best effort. Esto posee gran impacto en las aplicaciones que se corren, las cuales generan tráficos con diferentes requerimientos de recursos de la red. El presente trabajo tiene como objetivo fundamental analizar el comportamiento de la implementación de QoS en la sub capa MAC mediante 802.11e en ambientes con trá...

Evaluation and development the routing protocol of a fully functional simulation environment for VANETs

Science.gov (United States)

Ali, Azhar Tareq; Warip, Mohd Nazri Mohd; Yaakob, Naimah; Abduljabbar, Waleed Khalid; Atta, Abdu Mohammed Ali

2017-11-01

Vehicular Ad-hoc Networks (VANETs) is an area of wireless technologies that is attracting a great deal of interest. There are still several areas of VANETS, such as security and routing protocols, medium access control, that lack large amounts of research. There is also a lack of freely available simulators that can quickly and accurately simulate VANETs. The main goal of this paper is to develop a freely available VANETS simulator and to evaluate popular mobile ad-hoc network routing protocols in several VANETS scenarios. The VANETS simulator consisted of a network simulator, traffic (mobility simulator) and used a client-server application to keep the two simulators in sync. The VANETS simulator also models buildings to create a more realistic wireless network environment. Ad-Hoc Distance Vector routing (AODV), Dynamic Source Routing (DSR) and Dynamic MANET On-demand (DYMO) were initially simulated in a city, country, and highway environment to provide an overall evaluation.

Performance Analysis of On-Demand Routing Protocols in Wireless Mesh Networks

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Arafatur RAHMAN

2009-01-01

Full Text Available Wireless Mesh Networks (WMNs have recently gained a lot of popularity due to their rapid deployment and instant communication capabilities. WMNs are dynamically self-organizing, self-configuring and self-healing with the nodes in the network automatically establishing an adiej hoc network and preserving the mesh connectivity. Designing a routing protocol for WMNs requires several aspects to consider, such as wireless networks, fixed applications, mobile applications, scalability, better performance metrics, efficient routing within infrastructure, load balancing, throughput enhancement, interference, robustness etc. To support communication, various routing protocols are designed for various networks (e.g. ad hoc, sensor, wired etc.. However, all these protocols are not suitable for WMNs, because of the architectural differences among the networks. In this paper, a detailed simulation based performance study and analysis is performed on the reactive routing protocols to verify the suitability of these protocols over such kind of networks. Ad Hoc On-Demand Distance Vector (AODV, Dynamic Source Routing (DSR and Dynamic MANET On-demand (DYMO routing protocol are considered as the representative of reactive routing protocols. The performance differentials are investigated using varying traffic load and number of source. Based on the simulation results, how the performance of each protocol can be improved is also recommended.

Research on routing algorithm based on the VANET

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AN Li

2016-01-01

Full Text Available For the characteristics of high speed mobility of nodes, frequent changes of dynamic topology and frequent interrupts of the communication links in the VANET, this paper analyzed the defect of the current mobile ad-hoc network routing protocol, and carried on the simulation analysis on the adaptability of AODV, DSR and DSDV routing protocols in VANET applications in the VANET. Through the above research, this paper obtained the conclusion that the AODV routing protocol is more suitable for vehicular ad hoc network environment

Analyzing the Effectiveness of the Self-organized Public-Key Management System on MANETs under the Lack of Cooperation and the Impersonation Attacks

Science.gov (United States)

da Silva, Eduardo; Dos Santos, Aldri Luiz; Lima, Michele N.; Albini, Luiz Carlos Pessoa

Among the key management schemes for MANETs, the Self-Organized Public-Key Management System (PGP-Like) is the main chaining-based key management scheme. It is fully self-organized and does not require any certificate authority. Two kinds of misbehavior attacks are considered to be great threats to PGP-Like: lack of cooperation and impersonation attacks. This work quantifies the impact of such attacks on the PGP-Like. Simulation results show that PGP-Like was able to maintain its effectiveness when submitted to the lack of cooperation attack, contradicting previously theoretical results. It correctly works even in the presence of more than 60% of misbehaving nodes, although the convergence time is affected with only 20% of misbehaving nodes. On the other hand, PGP-Like is completely vulnerable to the impersonation attack. Its functionality is affected with just 5% of misbehaving nodes, confirming previously theoretical results.

A Protocol for Content-Based Communication in Disconnected Mobile Ad Hoc Networks

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Julien Haillot

2010-01-01

Full Text Available In content-based communication, information flows towards interested hosts rather than towards specifically set destinations. This new style of communication perfectly fits the needs of applications dedicated to information sharing, news distribution, service advertisement and discovery, etc. In this paper we address the problem of supporting content-based communication in partially or intermittently connected mobile ad hoc networks (MANETs. The protocol we designed leverages on the concepts of opportunistic networking and delay-tolerant networking in order to account for the absence of end-to-end connectivity in disconnected MANETs. The paper provides an overview of the protocol, as well as simulation results that show how this protocol can perform in realistic conditions.

Lifetime of Manet steel in load-cycling tests in vacuum at 20 and 550deg C

International Nuclear Information System (INIS)

Ullmaier, H.; Schmitz, W.

1989-01-01

Fatigue tests in vacuum were carried out on the Manet heat of DIN 1.4914 martensitic steel (X13Cr10.7Ni0.85Mo0.75V0.22) in push-pull type, stress-controlled experiments at room temperature and 823 K. The fatigue life was determined as a function of stress amplitude, mean stress, frequency and hold time. At 823 K creep has a strong influence on the life time, particularly at low frequencies and long hold times in tension. The results are phenomenologically described by a simple linear damage summation approach. Even at room temperature the life time of specimens tested in vacuum is about an order of magnitude higher than of those tested in air. This stresses the importance of providing the correct test environment in collecting fatigue data for the design of fusion devices. (orig./MM)

An improved AODV routing protocol based on tower structure

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Li Yong Qiang

2016-01-01

Full Text Available The paper proposed a new routing protocol(IAODV based on tower structure in the Ad Hoc network for the problem which Location Routing Protocol need hardware and Complex algorithm. By the simulation, The complexity of the new routing protocol is reduced without reducing the performance of the network.

ComboCoding: Combined intra-/inter-flow network coding for TCP over disruptive MANETs

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Chien-Chia Chen

2011-07-01

Full Text Available TCP over wireless networks is challenging due to random losses and ACK interference. Although network coding schemes have been proposed to improve TCP robustness against extreme random losses, a critical problem still remains of DATA–ACK interference. To address this issue, we use inter-flow coding between DATA and ACK to reduce the number of transmissions among nodes. In addition, we also utilize a “pipeline” random linear coding scheme with adaptive redundancy to overcome high packet loss over unreliable links. The resulting coding scheme, ComboCoding, combines intra-flow and inter-flow coding to provide robust TCP transmission in disruptive wireless networks. The main contributions of our scheme are twofold; the efficient combination of random linear coding and XOR coding on bi-directional streams (DATA and ACK, and the novel redundancy control scheme that adapts to time-varying and space-varying link loss. The adaptive ComboCoding was tested on a variable hop string topology with unstable links and on a multipath MANET with dynamic topology. Simulation results show that TCP with ComboCoding delivers higher throughput than with other coding options in high loss and mobile scenarios, while introducing minimal overhead in normal operation.

Data delivery method based on neighbor nodes' information in a mobile ad hoc network.

Science.gov (United States)

Kashihara, Shigeru; Hayashi, Takuma; Taenaka, Yuzo; Okuda, Takeshi; Yamaguchi, Suguru

2014-01-01

This paper proposes a data delivery method based on neighbor nodes' information to achieve reliable communication in a mobile ad hoc network (MANET). In a MANET, it is difficult to deliver data reliably due to instabilities in network topology and wireless network condition which result from node movement. To overcome such unstable communication, opportunistic routing and network coding schemes have lately attracted considerable attention. Although an existing method that employs such schemes, MAC-independent opportunistic routing and encoding (MORE), Chachulski et al. (2007), improves the efficiency of data delivery in an unstable wireless mesh network, it does not address node movement. To efficiently deliver data in a MANET, the method proposed in this paper thus first employs the same opportunistic routing and network coding used in MORE and also uses the location information and transmission probabilities of neighbor nodes to adapt to changeable network topology and wireless network condition. The simulation experiments showed that the proposed method can achieve efficient data delivery with low network load when the movement speed is relatively slow.

Data Delivery Method Based on Neighbor Nodes’ Information in a Mobile Ad Hoc Network

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Shigeru Kashihara

2014-01-01

Full Text Available This paper proposes a data delivery method based on neighbor nodes’ information to achieve reliable communication in a mobile ad hoc network (MANET. In a MANET, it is difficult to deliver data reliably due to instabilities in network topology and wireless network condition which result from node movement. To overcome such unstable communication, opportunistic routing and network coding schemes have lately attracted considerable attention. Although an existing method that employs such schemes, MAC-independent opportunistic routing and encoding (MORE, Chachulski et al. (2007, improves the efficiency of data delivery in an unstable wireless mesh network, it does not address node movement. To efficiently deliver data in a MANET, the method proposed in this paper thus first employs the same opportunistic routing and network coding used in MORE and also uses the location information and transmission probabilities of neighbor nodes to adapt to changeable network topology and wireless network condition. The simulation experiments showed that the proposed method can achieve efficient data delivery with low network load when the movement speed is relatively slow.

Mobility Aware Energy Efficient Clustering for MANET: A Bio-Inspired Approach with Particle Swarm Optimization

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Naghma Khatoon

2017-01-01

Full Text Available Mobility awareness and energy efficiency are two indispensable optimization problems in mobile ad hoc networks (MANETs where nodes move unpredictably in any direction with restricted battery life, resulting in frequent change in topology. These constraints are widely studied to increase the lifetime of such networks. This paper focuses on the problems of mobility as well as energy efficiency to develop a clustering algorithm inspired by multiagent stochastic parallel search technique of particle swarm optimization. The election of cluster heads takes care of mobility and remaining energy as well as the degree of connectivity for selecting nodes to serve as cluster heads for longer duration of time. The cluster formation is presented by taking multiobjective fitness function using particle swarm optimization. The proposed work is experimented extensively in the NS-2 network simulator and compared with the other existing algorithms. The results show the effectiveness of our proposed algorithm in terms of network lifetime, average number of clusters formed, average number of reclustering required, energy consumption, and packet delivery ratio.

Novel Clustering Method Based on K-Medoids and Mobility Metric

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Y. Hamzaoui

2018-06-01

Full Text Available The structure and constraint of MANETS influence negatively the performance of QoS, moreover the main routing protocols proposed generally operate in flat routing. Hence, this structure gives the bad results of QoS when the network becomes larger and denser. To solve this problem we use one of the most popular methods named clustering. The present paper comes within the frameworks of research to improve the QoS in MANETs. In this paper we propose a new algorithm of clustering based on the new mobility metric and K-Medoid to distribute the nodes into several clusters. Intuitively our algorithm can give good results in terms of stability of the cluster, and can also extend life time of cluster head.

Link reliability based hybrid routing for tactical mobile ad hoc network

Institute of Scientific and Technical Information of China (English)

Xie Xiaochuan; Wei Gang; Wu Keping; Wang Gang; Jia Shilou

2008-01-01

Tactical mobile ad hoc network (MANET) is a collection of mobile nodes forming a temporary network,without the aid of pre-established network infrastructure. The routing protocol has a crucial impact on the networkperformance in battlefields. Link reliability based hybrid routing (LRHR) is proposed, which is a novel hybrid routing protocol, for tactical MANET. Contrary to the traditional single path routing strategy, multiple paths are established between a pair of source-destination nodes. In the hybrid routing strategy, the rate of topological change provides a natural mechanism for switching dynamically between table-driven and on-demand routing. The simulation results indicate that the performances of the protocol in packet delivery ratio, routing overhead, and average end-to-end delay are better than the conventional routing protocol.

Position-Based Packet Forwarding for Vehicular Ad-Hoc Networks

OpenAIRE

Füßler, Holger

2007-01-01

Mobile Ad-Hoc Networks, or MANETs, are data communication networks between (potentially) mobile computer systems equipped with wireless communication devices and — in their purest form — in complete absence of communication infrastructure. Usage scenarios for these systems include communication during disaster recovery or battlefield communications. One of the great research challenges concerning MANETs is the Packet Forwarding Problem, i.e., the question to which neighbor node a data packet ...

Deny-by-Default Distributed Security Policy Enforcement in Mobile Ad Hoc Networks

Science.gov (United States)

Alicherry, Mansoor; Keromytis, Angelos D.; Stavrou, Angelos

Mobile Ad-hoc Networks (MANETs) are increasingly employed in tactical military and civil rapid-deployment networks, including emergency rescue operations and ad hoc disaster-relief networks. However, this flexibility of MANETs comes at a price, when compared to wired and base station-based wireless networks: MANETs are susceptible to both insider and outsider attacks. This is mainly because of the lack of a well-defined defense perimeter preventing the effective use of wired defenses including firewalls and intrusion detection systems.

DIRECTIONAL OPPORTUNISTIC MECHANISM IN CLUSTER MESSAGE CRITICALITY LEVEL BASED ZIGBEE ROUTING

OpenAIRE

B.Rajeshkanna *1, Dr.M.Anitha 2

2018-01-01

The cluster message criticality level based zigbee routing(CMCLZOR) has been proposed for routing the cluster messages in wireless smart energy home area networks. It employs zigbee opportunistic shortcut tree routing(ZOSTR) and AODV individually for routing normal messages and highly critical messages respectively. ZOSTR allows the receiving nodes to compete for forwarding a packet with the priority of left-over hops rather than stating single next hop node like unicast protocols. Since it h...

Implementing voice over Internet protocol in mobile ad hoc network – analysing its features regarding efficiency, reliability and security

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Naveed Ahmed Sheikh

2014-05-01

Full Text Available Providing secure and efficient real-time voice communication in mobile ad hoc network (MANET environment is a challenging problem. Voice over Internet protocol (VoIP has originally been developed over the past two decades for infrastructure-based networks. There are strict timing constraints for acceptable quality VoIP services, in addition to registration and discovery issues in VoIP end-points. In MANETs, ad hoc nature of networks and multi-hop wireless environment with significant packet loss and delays present formidable challenges to the implementation. Providing a secure real-time VoIP service on MANET is the main design objective of this paper. The authors have successfully developed a prototype system that establishes reliable and efficient VoIP communication and provides an extremely flexible method for voice communication in MANETs. The authors’ cooperative mesh-based MANET implementation can be used for rapidly deployable VoIP communication with survivable and efficient dynamic networking using open source software.

Mobile Ad Hoc Network Energy Cost Algorithm Based on Artificial Bee Colony

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Mustafa Tareq

2017-01-01

Full Text Available A mobile ad hoc network (MANET is a collection of mobile nodes that dynamically form a temporary network without using any existing network infrastructure. MANET selects a path with minimal number of intermediate nodes to reach the destination node. As the distance between each node increases, the quantity of transmission power increases. The power level of nodes affects the simplicity with which a route is constituted between a couple of nodes. This study utilizes the swarm intelligence technique through the artificial bee colony (ABC algorithm to optimize the energy consumption in a dynamic source routing (DSR protocol in MANET. The proposed algorithm is called bee DSR (BEEDSR. The ABC algorithm is used to identify the optimal path from the source to the destination to overcome energy problems. The performance of the BEEDSR algorithm is compared with DSR and bee-inspired protocols (BeeIP. The comparison was conducted based on average energy consumption, average throughput, average end-to-end delay, routing overhead, and packet delivery ratio performance metrics, varying the node speed and packet size. The BEEDSR algorithm is superior in performance than other protocols in terms of energy conservation and delay degradation relating to node speed and packet size.

ADAPTIVE CLUSTER BASED ROUTING PROTOCOL WITH ANT COLONY OPTIMIZATION FOR MOBILE AD-HOC NETWORK IN DISASTER AREA

Directory of Open Access Journals (Sweden)

Enrico Budianto

2012-07-01

Full Text Available In post-disaster rehabilitation efforts, the availability of telecommunication facilities takes important role. However, the process to improve telecommunication facilities in disaster area is risky if it is done by humans. Therefore, a network method that can work efficiently, effectively, and capable to reach the widest possible area is needed. This research introduces a cluster-based routing protocol named Adaptive Cluster Based Routing Protocol (ACBRP equipped by Ant Colony Optimization method, and its implementation in a simulator developed by author. After data analysis and statistical tests, it can be concluded that routing protocol ACBRP performs better than AODV and DSR routing protocol. Pada upaya rehabilitasi pascabencana, ketersediaan fasilitas telekomunikasi memiliki peranan yang sangat penting. Namun, proses untuk memperbaiki fasilitas telekomunikasi di daerah bencana memiliki resiko jika dilakukan oleh manusia. Oleh karena itu, metode jaringan yang dapat bekerja secara efisien, efektif, dan mampu mencapai area seluas mungkin diperlukan. Penelitian ini memperkenalkan sebuah protokol routing berbasis klaster bernama Adaptive Cluster Based Routing Protocol (ACBRP, yang dilengkapi dengan metode Ant Colony Optimization, dan diimplementasikan pada simulator yang dikembangkan penulis. Setelah data dianalisis dan dilakukan uji statistik, disimpulkan bahwa protokol routing ACBRP beroperasi lebih baik daripada protokol routing AODV maupun DSR.

Rollback recovery with low overhead for fault tolerance in mobile ad hoc networks

Directory of Open Access Journals (Sweden)

Parmeet Kaur Jaggi

2015-10-01

Full Text Available Mobile ad hoc networks (MANETs have significantly enhanced the wireless networks by eliminating the need for any fixed infrastructure. Hence, these are increasingly being used for expanding the computing capacity of existing networks or for implementation of autonomous mobile computing Grids. However, the fragile nature of MANETs makes the constituent nodes susceptible to failures and the computing potential of these networks can be utilized only if they are fault tolerant. The technique of checkpointing based rollback recovery has been used effectively for fault tolerance in static and cellular mobile systems; yet, the implementation of existing protocols for MANETs is not straightforward. The paper presents a novel rollback recovery protocol for handling the failures of mobile nodes in a MANET using checkpointing and sender based message logging. The proposed protocol utilizes the routing protocol existing in the network for implementing a low overhead recovery mechanism. The presented recovery procedure at a node is completely domino-free and asynchronous. The protocol is resilient to the dynamic characteristics of the MANET; allowing a distributed application to be executed independently without access to any wired Grid or cellular network access points. We also present an algorithm to record a consistent global snapshot of the MANET.

Analysis and Enhancements of Leader Elections algorithms in Mobile Ad Hoc Networks

OpenAIRE

Shayeji, Mohammad H. Al; Al-Azmi, AbdulRahman R.; Al-Azmi, AbdulAziz R.; Samrajesh, M. D.

2012-01-01

Mobile Ad Hoc networks (MANET), distinct from traditional distributed systems, are dynamic and self-organizing networks. MANET requires a leader to coordinate and organize tasks. The challenge is to have the right election algorithm that chooses the right leader based on various factors in MANET. In this paper, we analyze four leader election algorithms used in mobile Ad Hoc Networks. Factors considered in our analysis are time complexity, message complexity, assumptions considered, fault tol...

Energy-Aware Multipath Routing Scheme Based on Particle Swarm Optimization in Mobile Ad Hoc Networks.

Science.gov (United States)

Robinson, Y Harold; Rajaram, M

2015-01-01

Mobile ad hoc network (MANET) is a collection of autonomous mobile nodes forming an ad hoc network without fixed infrastructure. Dynamic topology property of MANET may degrade the performance of the network. However, multipath selection is a great challenging task to improve the network lifetime. We proposed an energy-aware multipath routing scheme based on particle swarm optimization (EMPSO) that uses continuous time recurrent neural network (CTRNN) to solve optimization problems. CTRNN finds the optimal loop-free paths to solve link disjoint paths in a MANET. The CTRNN is used as an optimum path selection technique that produces a set of optimal paths between source and destination. In CTRNN, particle swarm optimization (PSO) method is primly used for training the RNN. The proposed scheme uses the reliability measures such as transmission cost, energy factor, and the optimal traffic ratio between source and destination to increase routing performance. In this scheme, optimal loop-free paths can be found using PSO to seek better link quality nodes in route discovery phase. PSO optimizes a problem by iteratively trying to get a better solution with regard to a measure of quality. The proposed scheme discovers multiple loop-free paths by using PSO technique.

Mobility Based Key Management Technique for Multicast Security in Mobile Ad Hoc Networks

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B. Madhusudhanan

2015-01-01

Full Text Available In MANET multicasting, forward and backward secrecy result in increased packet drop rate owing to mobility. Frequent rekeying causes large message overhead which increases energy consumption and end-to-end delay. Particularly, the prevailing group key management techniques cause frequent mobility and disconnections. So there is a need to design a multicast key management technique to overcome these problems. In this paper, we propose the mobility based key management technique for multicast security in MANET. Initially, the nodes are categorized according to their stability index which is estimated based on the link availability and mobility. A multicast tree is constructed such that for every weak node, there is a strong parent node. A session key-based encryption technique is utilized to transmit a multicast data. The rekeying process is performed periodically by the initiator node. The rekeying interval is fixed depending on the node category so that this technique greatly minimizes the rekeying overhead. By simulation results, we show that our proposed approach reduces the packet drop rate and improves the data confidentiality.

WEAMR — A Weighted Energy Aware Multipath Reliable Routing Mechanism for Hotline-Based WSNs

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Ki-Hyung Kim

2013-05-01

Full Text Available Reliable source to sink communication is the most important factor for an efficient routing protocol especially in domains of military, healthcare and disaster recovery applications. We present weighted energy aware multipath reliable routing (WEAMR, a novel energy aware multipath routing protocol which utilizes hotline-assisted routing to meet such requirements for mission critical applications. The protocol reduces the number of average hops from source to destination and provides unmatched reliability as compared to well known reactive ad hoc protocols i.e., AODV and AOMDV. Our protocol makes efficient use of network paths based on weighted cost calculation and intelligently selects the best possible paths for data transmissions. The path cost calculation considers end to end number of hops, latency and minimum energy node value in the path. In case of path failure path recalculation is done efficiently with minimum latency and control packets overhead. Our evaluation shows that our proposal provides better end-to-end delivery with less routing overhead and higher packet delivery success ratio compared to AODV and AOMDV. The use of multipath also increases overall life time of WSN network using optimum energy available paths between sender and receiver in WDNs.

Drop-Burst Length Evaluation of Urban VANETs

Directory of Open Access Journals (Sweden)

Awos Kh. Ali

2017-05-01

Full Text Available Networks performance is traditionally evaluated using packet delivery ratio (PDR and latency (delay. We propose an addition mechanism the drop-burst length (DBL. Many traffic classes display varying application-level performance according to the pattern of drops, even if the PDR is similar. In this paper we study a number of VANET scenarios and evaluate them with these three metrics. Vehicular Ad-hoc Networks (VANETs are an emerging class of Mobile Ad-hoc Network (MANETs where nodes include both moving vehicles and fixed infrastructure. VANETs aim to make transportation systems more intelligent by sharing information to improve safety and comfort. Efficient and adaptive routing protocols are essential for achieving reliable and scalable network performance. However, routing in VANETs is challenging due to the frequent, high-speed movement of vehicles, which results in frequent network topology changes. Our simulations are carried out using NS2 (for network traffic and SUMO (for vehicular movement simulators, with scenarios configured to reflect real-world conditions. The results show that OLSR is able to achieve a best DBL performance and demonstrates higher PDR performance comparing to AODV and GPSR under low network load. However, with GPSR, the network shows more stable PDR under medium and high network load. In term of delay OLSR is outperformed by GPSR.

Secure Communication and Information Exchange using Authenticated Ciphertext Policy Attribute-Based Encryption in Mobile Ad-hoc Network

Directory of Open Access Journals (Sweden)

Samsul Huda

2016-08-01

Full Text Available MANETs are considered as suitable for commercial applications such as law enforcement, conference meeting, and sharing information in a student classroom and critical services such as military operations, disaster relief, and rescue operations. Meanwhile, in military operation especially in the battlefield in freely medium which naturally needs high mobility and flexibility. Thus, applying MANETs make these networks vulnerable to various types of attacks such aspacket eavesdropping, data disseminating, message replay, message modification, and especially privacy issue. In this paper, we propose a secure communication and information exchange in MANET with considering secure adhoc routing and secure information exchange. Regarding privacy issue or anonymity, we use a reliable asymmetric encryption which protecting user privacy by utilizing insensitive user attributes as user identity, CP-ABE (Ciphertext-Policy Attribute-Based Encryption cryptographic scheme. We also design protocols to implement the proposed scheme for various battlefied scenarios in real evironment using embedded devices. Our experimental results showed that the additional of HMAC (Keyed-Hash Message Authentication Code and AES (Advanced Encryption standard schemes using processor 1.2GHz only take processing time about 4.452 ms,  we can confirm that our approach by using CP-ABE with added HMAC and AES schemes make low overhead.

A lightweight neighbor-info-based routing protocol for no-base-station taxi-call system.

Science.gov (United States)

Zhu, Xudong; Wang, Jinhang; Chen, Yunchao

2014-01-01

Since the quick topology change and short connection duration, the VANET has had unstable routing and wireless signal quality. This paper proposes a kind of lightweight routing protocol-LNIB for call system without base station, which is applicable to the urban taxis. LNIB maintains and predicts neighbor information dynamically, thus finding the reliable path between the source and the target. This paper describes the protocol in detail and evaluates the performance of this protocol by simulating under different nodes density and speed. The result of evaluation shows that the performance of LNIB is better than AODV which is a classic protocol in taxi-call scene.

Monitoring and classifying animal behavior using ZigBee-based mobile ad hoc wireless sensor networks and artificial neural networks

DEFF Research Database (Denmark)

S. Nadimi, Esmaeil; Nyholm Jørgensen, Rasmus; Blanes-Vidal, Victoria

2012-01-01

Animal welfare is an issue of great importance in modern food production systems. Because animal behavior provides reliable information about animal health and welfare, recent research has aimed at designing monitoring systems capable of measuring behavioral parameters and transforming them...... into their corresponding behavioral modes. However, network unreliability and high-energy consumption have limited the applicability of those systems. In this study, a 2.4-GHz ZigBee-based mobile ad hoc wireless sensor network (MANET) that is able to overcome those problems is presented. The designed MANET showed high...... communication reliability, low energy consumption and low packet loss rate (14.8%) due to the deployment of modern communication protocols (e.g. multi-hop communication and handshaking protocol). The measured behavioral parameters were transformed into the corresponding behavioral modes using a multilayer...

A DNA-Inspired Encryption Methodology for Secure, Mobile Ad Hoc Networks

Science.gov (United States)

Shaw, Harry

2012-01-01

Users are pushing for greater physical mobility with their network and Internet access. Mobile ad hoc networks (MANET) can provide an efficient mobile network architecture, but security is a key concern. A figure summarizes differences in the state of network security for MANET and fixed networks. MANETs require the ability to distinguish trusted peers, and tolerate the ingress/egress of nodes on an unscheduled basis. Because the networks by their very nature are mobile and self-organizing, use of a Public Key Infra structure (PKI), X.509 certificates, RSA, and nonce ex changes becomes problematic if the ideal of MANET is to be achieved. Molecular biology models such as DNA evolution can provide a basis for a proprietary security architecture that achieves high degrees of diffusion and confusion, and resistance to cryptanalysis. A proprietary encryption mechanism was developed that uses the principles of DNA replication and steganography (hidden word cryptography) for confidentiality and authentication. The foundation of the approach includes organization of coded words and messages using base pairs organized into genes, an expandable genome consisting of DNA-based chromosome keys, and a DNA-based message encoding, replication, and evolution and fitness. In evolutionary computing, a fitness algorithm determines whether candidate solutions, in this case encrypted messages, are sufficiently encrypted to be transmitted. The technology provides a mechanism for confidential electronic traffic over a MANET without a PKI for authenticating users.

PSO-Optimized Hopfield Neural Network-Based Multipath Routing for Mobile Ad-hoc Networks

Directory of Open Access Journals (Sweden)

Mansour Sheikhan

2012-06-01

Full Text Available Mobile ad-hoc network (MANET is a dynamic collection of mobile computers without the need for any existing infrastructure. Nodes in a MANET act as hosts and routers. Designing of robust routing algorithms for MANETs is a challenging task. Disjoint multipath routing protocols address this problem and increase the reliability, security and lifetime of network. However, selecting an optimal multipath is an NP-complete problem. In this paper, Hopfield neural network (HNN which its parameters are optimized by particle swarm optimization (PSO algorithm is proposed as multipath routing algorithm. Link expiration time (LET between each two nodes is used as the link reliability estimation metric. This approach can find either node-disjoint or link-disjoint paths in singlephase route discovery. Simulation results confirm that PSO-HNN routing algorithm has better performance as compared to backup path set selection algorithm (BPSA in terms of the path set reliability and number of paths in the set.

Organization model for Mobile Wireless Sensor Networks inspired in Artificial Bee Colony

International Nuclear Information System (INIS)

Julio de Mesquita Filho, Sao Jose do Rio Preto, SP (Brazil))" data-affiliation=" (Sao Paulo State Univerity Julio de Mesquita Filho, Sao Jose do Rio Preto, SP (Brazil))" >Roberto, Guilherme Freire; Julio de Mesquita Filho, Sao Jose do Rio Preto, SP (Brazil))" data-affiliation=" (Sao Paulo State Univerity Julio de Mesquita Filho, Sao Jose do Rio Preto, SP (Brazil))" >Neves, Leandro Alves; Maschi, Luis Fernando Castilho; Pigatto, Daniel Fernando; Branco, Kalinka Regina Lucas Jaquie Castelo; Montez, Carlos; Pinto, Alex Sandro Roschildt

2015-01-01

The purpose of this study is to find a self-organizing model for MWSN based on bee colonies in order to reduce the number of messages transmitted among nodes, and thus reduce the overall consumption energy while maintaining the efficiency of message delivery. The results obtained in this article are originated from simulations carried out with SINALGO software, which demonstrates the effectiveness of the proposed approach. The BeeAODV (Bee Ad-Hoc On Demand Distance Vector) proposed in this paper allows to considerably reduce message exchanges whether compared to AODV (Ad-Hoc On Demand Distance Vector)

Sadhana | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Sadhana. N Shanthi. Articles written in Sadhana. Volume 40 Issue 8 December 2015 pp 2341-2352. Genetic based optimization for multicast routing algorithm for MANET · C Rajan N Shanthi · More Details Abstract Fulltext PDF. Mobile Ad hoc Network (MANET) is established for a limited period, for special ...

Sadhana | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Sadhana. C Rajan. Articles written in Sadhana. Volume 40 Issue 8 December 2015 pp 2341-2352. Genetic based optimization for multicast routing algorithm for MANET · C Rajan N Shanthi · More Details Abstract Fulltext PDF. Mobile Ad hoc Network (MANET) is established for a limited period, for special ...

Analysis of Pervasive Mobile Ad Hoc Routing Protocols

Science.gov (United States)

Qadri, Nadia N.; Liotta, Antonio

Mobile ad hoc networks (MANETs) are a fundamental element of pervasive networks and therefore, of pervasive systems that truly support pervasive computing, where user can communicate anywhere, anytime and on-the-fly. In fact, future advances in pervasive computing rely on advancements in mobile communication, which includes both infrastructure-based wireless networks and non-infrastructure-based MANETs. MANETs introduce a new communication paradigm, which does not require a fixed infrastructure - they rely on wireless terminals for routing and transport services. Due to highly dynamic topology, absence of established infrastructure for centralized administration, bandwidth constrained wireless links, and limited resources in MANETs, it is challenging to design an efficient and reliable routing protocol. This chapter reviews the key studies carried out so far on the performance of mobile ad hoc routing protocols. We discuss performance issues and metrics required for the evaluation of ad hoc routing protocols. This leads to a survey of existing work, which captures the performance of ad hoc routing algorithms and their behaviour from different perspectives and highlights avenues for future research.

CERTIFICATE REVOCATION SCHEME BASED ON WEIGHTED VOTING GAME AND RATIONAL SECURE MULTIPARTY COMPUTING

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N Aravinthan

2017-03-01

Full Text Available The Mobile Adhoc Network consists of deployed mobile nodes which lead to the frequent changes in network topology. Due to topology changes, required infrastructure is unavailable for communication. Moreover, malicious nodes present in MANET make use of this modification and can easily launch highly vulnerable attacks on the routing path of the network. Hence, Security issue such as removing misbehaving nodes is the primary issue in MANET. Effective certificate revocation scheme was introduced to identify and eliminate the node with malicious activities in the network based on the weighted voting game (ECR-WVG approach. In this approach, weights and quota were two factors, determined for an effective revocation of malicious nodes certificates. However, security during multiparty transmission was not taken into account in ECR-WVG. In Effective Certificate Revocation Scheme based on Weighted Voting Game and Rational Secure Multi-Party Computing (ECR-WVG-RSMPC method, rational secret sharing scheme is introduced along with ECR-WVG approach for securing multiparty transmission. Performance evaluation can be done between ECR-WVG and ECR-WVG-RSMPC in terms of false revocation, malicious node revocation, normalized time for revocation and revocation accuracy ratio.

Trust-based hexagonal clustering for efficient certificate ...

Indian Academy of Sciences (India)

Clustering; certificate management; MANET; security; trust; Voronoi. ... terms of effectiveness of revocation scheme (with respect to revocation rate and time), security, ... Engineering, Thiagarajar College of Engineering, Madurai 625015, India ...

High throughput route selection in multi-rate wireless mesh networks

Institute of Scientific and Technical Information of China (English)

WEI Yi-fei; GUO Xiang-li; SONG Mei; SONG Jun-de

2008-01-01

Most existing Ad-hoc routing protocols use the shortest path algorithm with a hop count metric to select paths. It is appropriate in single-rate wireless networks, but has a tendency to select paths containing long-distance links that have low data rates and reduced reliability in multi-rate networks. This article introduces a high throughput routing algorithm utilizing the multi-rate capability and some mesh characteristics in wireless fidelity (WiFi) mesh networks. It uses the medium access control (MAC) transmission time as the routing metric, which is estimated by the information passed up from the physical layer. When the proposed algorithm is adopted, the Ad-hoc on-demand distance vector (AODV) routing can be improved as high throughput AODV (HT-AODV). Simulation results show that HT-AODV is capable of establishing a route that has high data-rate, short end-to-end delay and great network throughput.

Modelling and Initial Validation of the DYMO Routing Protocol for Mobile Ad-Hoc Networks

DEFF Research Database (Denmark)

Espensen, Kristian Asbjørn Leth; Kjeldsen, Mads Keblov; Kristensen, Lars Michael

2008-01-01

A mobile ad-hoc network (MANET) is an infrastructureless network established by a set of mobile devices using wireless communication. The Dynamic MANET On-demand (DYMO) protocol is a routing protocol for multi-hop communication in MANETs currently under development by the Internet Engineering Task...... Force (IETF). This paper presents a Coloured Petri Net (CPN) model of the mandatory parts of the DYMO protocol, and shows how scenario-based state space exploration has been used to validate key properties of the protocol. Our CPN modelling and verification work has spanned two revisions of the DYMO...... protocol specification and have had direct impact on the most recent version of the protocol specification....

IDMA: improving the defense against malicious attack for mobile ad hoc networks based on ARIP protocol

Science.gov (United States)

Peng, Chaorong; Chen, Chang Wen

2008-04-01

Malicious nodes are mounting increasingly sophisticated attacking operations on the Mobile Ad Hoc Networks (MANETs). This is mainly because the IP-based MANETs are vulnerable to attacks by various malicious nodes. However, the defense against malicious attack can be improved when a new layer of network architecture can be developed to separate true IP address from disclosing to the malicious nodes. In this paper, we propose a new algorithm to improve the defense against malicious attack (IDMA) that is based on a recently developed Assignment Router Identify Protocol (ARIP) for the clustering-based MANET management. In the ARIP protocol, we design the ARIP architecture based on the new Identity instead of the vulnerable IP addresses to provide the required security that is embedded seamlessly into the overall network architecture. We make full use of ARIP's special property to monitor gateway forward packets by Reply Request Route Packets (RREP) without additional intrusion detection layer. We name this new algorithm IDMA because of its inherent capability to improve the defense against malicious attacks. Through IDMA, a watching algorithm can be established so as to counterattack the malicious node in the routing path when it unusually drops up packets. We provide analysis examples for IDMA for the defense against a malicious node that disrupts the route discovery by impersonating the destination, or by responding with state of corrupted routing information, or by disseminating forged control traffic. The IDMA algorithm is able to counterattack the malicious node in the cases when the node lunch DoS attack by broadcast a large number of route requests, or make Target traffic congestion by delivering huge mount of data; or spoof the IP addresses and send forge packets with a fake ID to the same Target causing traffic congestion at that destination. We have implemented IDMA algorism using the GloMoSim simulator and have demonstrated its performance under a variety of

Modelling of Picosatellite Constellation-Based Network and Effects on Quality of Service

Science.gov (United States)

2015-03-01

7]. The successful launch of Sputnik, the first man- made satellite, by the Soviet Union in 1957 was momentous in mankind’s history . Fortunately the...Transmission Power 27 dBm MAC Protocol Generic MAC No. of IP Output Queue 1 Routing Protocol IPv4 Ad-hoc On-demand Distance Vector (AODV) [13

Application of Swarm Intelligence Based Routingprotocols for Wireless Adhoc Sensor Network

Directory of Open Access Journals (Sweden)

Mrutyunjaya PANDA

2011-07-01

Full Text Available The enormous growth of wireless sensor network (WSN research has opined challenges about their ease in implementation and performance evaluation. Efficient swarm intelligence based routing protocols that can be used to obtain the application specific service guarantee are the key design issues in designing a WSN model. In this paper, an experimental testbed is designed with 100 sensor nodes deployed in a dense environment to address the scalability and performance issues of WSN. In this paper, we use Flooded Piggyback (FP and SC-MCBR ant colony based routing along with AODV and MCBR Tree in order to design an efficient WSN model. Finally, simulation results are presented with various performance measures to understand the efficacy of the proposed WSN design.

Wireless Sensor Network Quality of Service Improvement on Flooding Attack Condition

Science.gov (United States)

Hartono, R.; Widyawan; Wibowo, S. B.; Purnomo, A.; Hartatik

2018-03-01

There are two methods of building communication using wireless media. The first method is building a base infrastructure as an intermediary between users. Problems that arise on this type of network infrastructure is limited space to build any network physical infrastructure and also the cost factor. The second method is to build an ad hoc network between users who will communicate. On ad hoc network, each user must be willing to send data from source to destination for the occurrence of a communication. One of network protocol in Ad Hoc, Ad hoc on demand Distance Vector (AODV), has the smallest overhead value, easier to adapt to dynamic network and has small control message. One AODV protocol’s drawback is route finding process’ security for sending the data. In this research, AODV protocol is optimized by determining Expanding Ring Search (ERS) best value. Random topology is used with variation in the number of nodes: 25, 50, 75, 100, 125 and 150 with node’s speed of 10m/s in the area of 1000m x 1000m on flooding network condition. Parameters measured are Throughput, Packet Delivery Ratio, Average Delay and Normalized Routing Load. From the test results of AODV protocol optimization with best value of Expanding Ring Search (ERS), throughput increased by 5.67%, packet delivery ratio increased by 5.73%, and as for Normalized Routing Load decreased by 4.66%. ERS optimal value for each node’s condition depending on the number of nodes on the network.

A Conceptual Framework for Representing Human Behavior Characteristics in a System of Systems Agent-based Survivability Simulation-Intelligent Networks

Science.gov (United States)

2014-10-17

2012: Leadership award, Biotechnology in Piedmond Triad. 2010-2012 Board member, Gateway University Research Park, Inc., Greensboro. 2010-2012...Carolina Biotechnology . 2010-2012 Board member, The Oak Ridge Associated Universities (ORAU) Historically Black Colleges and Universities/ Minority... Magazine , 50 (7), 121 – 127. Wei, W. & GuoSun, Z. (2010). Bayesian cognitive trust model based self-clustering algorithm for MANETs. Information

Construction of Pipelined Strategic Connected Dominating Set for Mobile Ad Hoc Networks

Directory of Open Access Journals (Sweden)

Ceronmani Sharmila

2016-06-01

Full Text Available Efficient routing between nodes is the most important challenge in a Mobile Ad Hoc Network (MANET. A Connected Dominating Set (CDS acts as a virtual backbone for routing in a MANET. Hence, the construction of CDS based on the need and its application plays a vital role in the applications of MANET. The PipeLined Strategic CDS (PLS-CDS is constructed based on strategy, dynamic diameter and transmission range. The strategy used for selecting the starting node is, any source node in the network, which has its entire destination within a virtual pipelined coverage, instead of the node with maximum connectivity. The other nodes are then selected based on density and velocity. The proposed CDS also utilizes the energy of the nodes in the network in an optimized manner. Simulation results showed that the proposed algorithm is better in terms of size of the CDS and average hop per path length.

How Effective is Routing for Wireless Networking

Science.gov (United States)

2016-03-05

order to avoid the effects of congestion and queue overflows, data rates are set arbitrarily high. For both OLSR and AODV, we test two variants...aodv version 2,” in Vehicular Technology Conference (VTC Fall), 2012 IEEE. IEEE, 2012, pp. 1–5. [11] T. Clausen, A. C. de Verdiere, J. Yi, A. Niktash, Y

A Performance Evaluation Model for Mobile Ad Hoc Networks and Sensor Networks

Directory of Open Access Journals (Sweden)

Heng LUO

2014-03-01

Full Text Available Potential applications in areas such as military sites and disaster relief fields that are characterized by absence of prefixed infrastructure justify the development of mobile ad hoc networks (MANETs and wireless sensor networks (WSNs. However, unfavorable wireless links and dynamic topology are still challenging, leading to the proposal of a collection of routing protocols for MANETs and WSNs. Nevertheless the performance of algorithms may vary with deployment scenario due to the application dependent philosophy behind algorithms. In this paper, the performance evaluation problem for MANETs and WSNs is investigated and a novel performance ranking model, termed AHP-SAW, is proposed. For simplicity but without loss of generality, the performance of two routing protocols DSDV and DSR are studies based on which ranking results are provided. Extensive simulations show that an overall 37.2 %, at most, gain may be achieved based on the AHP-SAW model.

Energy-Efficient Cluster Based Routing Protocol in Mobile Ad Hoc Networks Using Network Coding

OpenAIRE

Srinivas Kanakala; Venugopal Reddy Ananthula; Prashanthi Vempaty

2014-01-01

In mobile ad hoc networks, all nodes are energy constrained. In such situations, it is important to reduce energy consumption. In this paper, we consider the issues of energy efficient communication in MANETs using network coding. Network coding is an effective method to improve the performance of wireless networks. COPE protocol implements network coding concept to reduce number of transmissions by mixing the packets at intermediate nodes. We incorporate COPE into cluster based routing proto...

Effective ANT based Routing Algorithm for Data Replication in MANETs

Directory of Open Access Journals (Sweden)

N.J. Nithya Nandhini

2013-12-01

Full Text Available In mobile ad hoc network, the nodes often move and keep on change its topology. Data packets can be forwarded from one node to another on demand. To increase the data accessibility data are replicated at nodes and made as sharable to other nodes. Assuming that all mobile host cooperative to share their memory and allow forwarding the data packets. But in reality, all nodes do not share the resources for the benefits of others. These nodes may act selfishly to share memory and to forward the data packets. This paper focuses on selfishness of mobile nodes in replica allocation and routing protocol based on Ant colony algorithm to improve the efficiency. The Ant colony algorithm is used to reduce the overhead in the mobile network, so that it is more efficient to access the data than with other routing protocols. This result shows the efficiency of ant based routing algorithm in the replication allocation.

Mobile Ad Hoc Networks in Bandwidth-Demanding Mission-Critical Applications: Practical Implementation Insights

KAUST Repository

Bader, Ahmed

2016-09-28

There has been recently a growing trend of using live video feeds in mission-critical applications. Real-time video streaming from front-end personnel or mobile agents is believed to substantially improve situational awareness in mission-critical operations such as disaster relief, law enforcement, and emergency response. Mobile Ad Hoc Networks (MANET) is a natural contender in such contexts. However, classical MANET routing schemes fall short in terms of scalability, bandwidth and latency; all three metrics being quite essential for mission-critical applications. As such, autonomous cooperative routing (ACR) has gained traction as the most viable MANET proposition. Nonetheless, ACR is also associated with a few implementation challenges. If they go unaddressed, will deem ACR practically useless. In this paper, efficient and low-complexity remedies to those issues are presented, analyzed, and validated. The validation is based on field experiments carried out using software-defined radio (SDR) platforms. Compared to classical MANET routing schemes, ACR was shown to offer up to 2X better throughput, more than 4X reduction in end-to-end latency, while observing a given target of transport rate normalized to energy consumption.

Optimal JPWL Forward Error Correction Rate Allocation for Robust JPEG 2000 Images and Video Streaming over Mobile Ad Hoc Networks

Directory of Open Access Journals (Sweden)

Benoit Macq

2008-07-01

Full Text Available Based on the analysis of real mobile ad hoc network (MANET traces, we derive in this paper an optimal wireless JPEG 2000 compliant forward error correction (FEC rate allocation scheme for a robust streaming of images and videos over MANET. The packet-based proposed scheme has a low complexity and is compliant to JPWL, the 11th part of the JPEG 2000 standard. The effectiveness of the proposed method is evaluated using a wireless Motion JPEG 2000 client/server application; and the ability of the optimal scheme to guarantee quality of service (QoS to wireless clients is demonstrated.

Energy Efficient Routing in Wireless Sensor Networks based on Ant ...

African Journals Online (AJOL)

PROF. O. E. OSUAGWU

2013-09-01

Sep 1, 2013 ... improved Ant System and their application in WSN routing process. The simulation results show ... and Mobile ad-hoc networks (MANETs) are inappropriate for ... Dorigo in 1992 in his PhD thesis, the first algorithm was aiming ...

Design and Analysis of QoS Routing Framework integrated with OLSR protocol for Multimedia Traffic in Mobile Adhoc Networks

Directory of Open Access Journals (Sweden)

S. Soni

2017-06-01

Full Text Available MANETs (Mobile Ad-hoc Networks is the self organizing wireless structure of mobile hosts. Wireless media is used for communication in MANETs. Considering the developing requirements for multimedia and real-time traffic applications in real world, QoS (Quality-of-Service support is essential in MANETs. But most of the characteristics of MANETs make QoS support a difficult problem. It is challenging to support QoS routing in MANET due to dynamic behavior and mobility of the hosts. The OLSR (Optimized Link State Routing protocol can be efficiently used in MANETs to provide QoS routing because of its dynamic MPR (Multi Point Relay selection criteria and proactive nature. In this paper, a design of QoS routing framework integrated with OLSR protocol is proposed and also analyzed using network simulator. Proposed QoS framework combines a bandwidth estimation algorithm with explicit resource reservation, QoS routing and connection admission control (CAC. OLSR protocol is extended for QoS framework to solve performance issues related to node mobility using cross layer approach. Results after simulation conclude about efficiency of the proposed QoS routing framework.

A survey and taxonomy of distributed certificate authorities in mobile ad hoc networks

Directory of Open Access Journals (Sweden)

Jabbehdari Sam

2011-01-01

Full Text Available Abstract Certificate authorities (CAs are the main components of PKI that enable us for providing basic security services in wired networks and Internet. But, we cannot use centralized CAs, in mobile ad hoc networks (MANETs. So, many efforts have been made to adapt CA to the special characteristics of MANETs and new concepts such as distributed CAs (DCAs have been proposed that distribute the functionality of CA between MANET nodes. In this article, we study various proposed DCA schemes for MANET and then classify these schemes according to their internal structures and techniques. Finally, we propose the characteristics of an ideal DCA system that can be used to verify the completeness of any DCA scheme. This classification and taxonomy identify the weakness and constraints of each scheme, and are very important for designing more secure, scalable, and high performance DCA systems for MANETs and other networks.

Delay-dependent asymptotic stability of mobile ad-hoc networks: A descriptor system approach

International Nuclear Information System (INIS)

Yang Juan; Yang Dan; Zhang Xiao-Hong; Huang Bin; Luo Jian-Lu

2014-01-01

In order to analyze the capacity stability of the time-varying-propagation and delay-dependent of mobile ad-hoc networks (MANETs), in this paper, a novel approach is proposed to explore the capacity asymptotic stability for the delay-dependent of MANETs based on non-cooperative game theory, where the delay-dependent conditions are explicitly taken into consideration. This approach is based on the Lyapunov—Krasovskii stability theory for functional differential equations and the linear matrix inequality (LMI) technique. A corresponding Lyapunov—Krasovskii functional is introduced for the stability analysis of this system with use of the descriptor and “neutral-type” model transformation without producing any additional dynamics. The delay-dependent stability criteria are derived for this system. Conditions are given in terms of linear matrix inequalities, and for the first time referred to neutral systems with the time-varying propagation and delay-dependent stability for capacity analysis of MANETs. The proposed criteria are less conservative since they are based on an equivalent model transformation. Furthermore, we also provide an effective and efficient iterative algorithm to solve the constrained stability control model. Simulation experiments have verified the effectiveness and efficiency of our algorithm. (general)

Data management issues in mobile ad hoc networks.

Science.gov (United States)

Hara, Takahiro

2017-01-01

Research on mobile ad hoc networks (MANETs) has become a hot research topic since the middle 1990's. Over the first decade, most research focused on networking techniques, ignoring data management issues. We, however, realized early the importance of data management in MANETs, and have been conducting studies in this area for 15 years. In this review, we summarize some key technical issues related to data management in MANETs, and the studies we have done in addressing these issues, which include placement of data replicas, update management, and query processing with security management. The techniques proposed in our studies have been designed with deep considerations of MANET features including network partitioning, node participation/disappearance, limited network bandwidth, and energy efficiency. Our studies published in early 2000's have developed a new research field as data management in MANETs. Also, our recent studies are expected to be significant guidelines of new research directions. We conclude the review by discussing some future directions for research.

Automatic Structure-Based Code Generation from Coloured Petri Nets

DEFF Research Database (Denmark)

Kristensen, Lars Michael; Westergaard, Michael

2010-01-01

Automatic code generation based on Coloured Petri Net (CPN) models is challenging because CPNs allow for the construction of abstract models that intermix control flow and data processing, making translation into conventional programming constructs difficult. We introduce Process-Partitioned CPNs...... (PP-CPNs) which is a subclass of CPNs equipped with an explicit separation of process control flow, message passing, and access to shared and local data. We show how PP-CPNs caters for a four phase structure-based automatic code generation process directed by the control flow of processes....... The viability of our approach is demonstrated by applying it to automatically generate an Erlang implementation of the Dynamic MANET On-demand (DYMO) routing protocol specified by the Internet Engineering Task Force (IETF)....

Enhancing On-Demand Multicast Routing Protocols using Mobility Prediction in Mobile Ad-hoc Network

Directory of Open Access Journals (Sweden)

Nermin Makhlouf

2014-08-01

Full Text Available A Mobile Ad hoc Network (MANET is a self-organizing wireless communication network in which mobile devices are based on no infrastructure like base stations or access points. Minimal configuration and quick deployment make ad hoc networks suitable for emergency situations like disaster recovery or military conflict. Since node mobility may cause links to be broken frequently, a very important issue for routing in MANETs is how to set reliable paths which can last as long as possible. To solve this problem, non-random behaviors for the mobility patterns that mobile users exhibit are exploited. This paper introduces a scheme to improve On-Demand Multicast Routing Protocol (ODMRP performances by using mobility prediction. 

TIGeR : A Traffic-Aware Intersection-Based Geographical routing protocol for urban VANETs

NARCIS (Netherlands)

Tavakoli, Rasool; Nabi, M.

2013-01-01

In recent years, vehicular ad-hoc networks (VANETs) have received increasing interests because of their promising solutions in many urban applications. VANETs are distinguished from other kinds of ad-hoc networks, such as Mobile Ad-hoc Networks (MANETs), by high mobility and reduced communications.

A novel approach to Service Discovery in Mobile Adhoc Network

OpenAIRE

Islam, Noman; Shaikh, Zubair A.

2015-01-01

Mobile Adhoc Network (MANET) is a network of a number of mobile routers and associated hosts, organized in a random fashion via wireless links. During recent years MANET has gained enormous amount of attention and has been widely used for not only military purposes but for search-and-rescue operations, intelligent transportation system, data collection, virtual classrooms and ubiquitous computing. Service Discovery is one of the most important issues in MANET. It is defined as the process of ...

Intelligent Broadcasting in Mobile Ad Hoc Networks: Three Classes of Adaptive Protocols

Directory of Open Access Journals (Sweden)

Michael D. Colagrosso

2006-11-01

Full Text Available Because adaptability greatly improves the performance of a broadcast protocol, we identify three ways in which machine learning can be applied to broadcasting in a mobile ad hoc network (MANET. We chose broadcasting because it functions as a foundation of MANET communication. Unicast, multicast, and geocast protocols utilize broadcasting as a building block, providing important control and route establishment functionality. Therefore, any improvements to the process of broadcasting can be immediately realized by higher-level MANET functionality and applications. While efficient broadcast protocols have been proposed, no single broadcasting protocol works well in all possible MANET conditions. Furthermore, protocols tend to fail catastrophically in severe network environments. Our three classes of adaptive protocols are pure machine learning, intra-protocol learning, and inter-protocol learning. In the pure machine learning approach, we exhibit a new approach to the design of a broadcast protocol: the decision of whether to rebroadcast a packet is cast as a classification problem. Each mobile node (MN builds a classifier and trains it on data collected from the network environment. Using intra-protocol learning, each MN consults a simple machine model for the optimal value of one of its free parameters. Lastly, in inter-protocol learning, MNs learn to switch between different broadcasting protocols based on network conditions. For each class of learning method, we create a prototypical protocol and examine its performance in simulation.

Intelligent Broadcasting in Mobile Ad Hoc Networks: Three Classes of Adaptive Protocols

Directory of Open Access Journals (Sweden)

Colagrosso Michael D

2007-01-01

Full Text Available Because adaptability greatly improves the performance of a broadcast protocol, we identify three ways in which machine learning can be applied to broadcasting in a mobile ad hoc network (MANET. We chose broadcasting because it functions as a foundation of MANET communication. Unicast, multicast, and geocast protocols utilize broadcasting as a building block, providing important control and route establishment functionality. Therefore, any improvements to the process of broadcasting can be immediately realized by higher-level MANET functionality and applications. While efficient broadcast protocols have been proposed, no single broadcasting protocol works well in all possible MANET conditions. Furthermore, protocols tend to fail catastrophically in severe network environments. Our three classes of adaptive protocols are pure machine learning, intra-protocol learning, and inter-protocol learning. In the pure machine learning approach, we exhibit a new approach to the design of a broadcast protocol: the decision of whether to rebroadcast a packet is cast as a classification problem. Each mobile node (MN builds a classifier and trains it on data collected from the network environment. Using intra-protocol learning, each MN consults a simple machine model for the optimal value of one of its free parameters. Lastly, in inter-protocol learning, MNs learn to switch between different broadcasting protocols based on network conditions. For each class of learning method, we create a prototypical protocol and examine its performance in simulation.

QoS frameworks for Multimedia Traffic in Mobile Adhoc Networks: A Comparative Review

Directory of Open Access Journals (Sweden)

S. Soni

2017-06-01

Full Text Available MANETs (Mobile Adhoc Networks has gained an increased interest by the research community. Regular intelligent exchanges of multimedia will be typical in MANET, though the extended motivation on QoS (Quality of Service. However, various properties of the discussed QoS framework are provisioned for QoS as a challenging concern. Providing QoS provisioning is, to a great degree, challenging in MANETs in view of bouncing correspondences, center point movability and nonattendance of central coordination. Thus, most of the research has focused on giving QoS guarantees in MANETs coordinating traditions. Though huge numbers of QoS coordinating procedures have been proposed in composing, focusing on different QoS estimations yet none of the prescribed or discussed frameworks achieves a universal course of action. There exist several genuine necessary research areas of focus such as QoS metric assurance and cost limit layout, source level scheduling framework and QoS coordinating. In this paper, working and connecting of various QoS frameworks for MANETs is investigated throughout several veritable focus areas of research. After a comparative review, it is concluded that there is still a good scope of research for proposing a QoS framework for MANETs which could have cross-layer advantages, resource reservation, connection admission control, multi-constrained QoS parameters, hard QoS assurance, proactive routing advantages etc.

Reputation-Based Internet Protocol Security: A Multilayer Security Framework for Mobile Ad Hoc Networks

Science.gov (United States)

2010-09-01

motivated research in behavior grading systems [56]. Peer-to-peer eCommerce appli- cations such as eBay, Amazon, uBid, and Yahoo have performed research that...Security in Mobile Ad Hoc Networks”. IEEE Security & Privacy , 72–75, 2008. 15. Chakeres, ID and EM Belding-Royer. “AODV Routing Protocol Implementa...Detection System”. Proceedings of IEEE Computer Society Symposium on Research in Security and Privacy , 240–250. 1992. 21. Devore, J.L. and N.R. Farnum

Coolant compatibility studies. The effect of irradiation on tensile properties and stress corrosion cracking sensitivity of martensitic steels. MANET 4 - complementary studies

International Nuclear Information System (INIS)

Nystrand, A.C.

1994-02-01

Tensile and stress corrosion cracking tests have been carried out on MANET-type (1.4914 and FV448) and reduced activation (LA12TaLC) high-chromium martensitic steels. The materials had previously been exposed up to 5000 h at ∼275 degrees C in the core, above the core and remote from the core of a high pressure water loop in the Studsvik R2 reactor. After the mechanical testing the materials were examined visually and metallographically. The steel samples exposed in the core section showed large increases in tensile yield strengths when tested at 250 degrees C. However, the magnitude of the radiation hardening was considerably smaller in the reduced activation steel compared to the commercial steels; this observation is consistent with published data on other high-chromium martensitic steels and is associated with the lower chromium content of the LA12TaLC steel (8.9%) compared with those of the commercial steels (10.6 and 11.3%). Irradiation assisted stress corrosion cracking (IASCC) was not detected in any of the stressed steel samples after autoclave testing for times up to 1500 h at 250 degrees C in air-saturated high purity water. This apparent resistance to IASCC may be due to the high chromium martensitic steels not being sensitized by the irradiation in a comparable manner to that shown by the austenitic steels. However, additional studies are required to clarify some of the existing uncertainties with respect to IASCC of these martensitic steels

Sadhana | Indian Academy of Sciences

Indian Academy of Sciences (India)

Preventing the impact of selfish behavior under MANET using Neighbor Credit Value ... Mobile Ad hoc Network (MANET) nodes exchange information using the ... Routing protocol plays a crucial role in an effective communication between ...

Applying self-organizing map and modified radial based neural network for clustering and routing optimal path in wireless network

Science.gov (United States)

Hoomod, Haider K.; Kareem Jebur, Tuka

2018-05-01

Mobile ad hoc networks (MANETs) play a critical role in today’s wireless ad hoc network research and consist of active nodes that can be in motion freely. Because it consider very important problem in this network, we suggested proposed method based on modified radial basis function networks RBFN and Self-Organizing Map SOM. These networks can be improved by the use of clusters because of huge congestion in the whole network. In such a system, the performance of MANET is improved by splitting the whole network into various clusters using SOM. The performance of clustering is improved by the cluster head selection and number of clusters. Modified Radial Based Neural Network is very simple, adaptable and efficient method to increase the life time of nodes, packet delivery ratio and the throughput of the network will increase and connection become more useful because the optimal path has the best parameters from other paths including the best bitrate and best life link with minimum delays. Proposed routing algorithm depends on the group of factors and parameters to select the path between two points in the wireless network. The SOM clustering average time (1-10 msec for stall nodes) and (8-75 msec for mobile nodes). While the routing time range (92-510 msec).The proposed system is faster than the Dijkstra by 150-300%, and faster from the RBFNN (without modify) by 145-180%.

Overview of the Meraka wireless grid test bed for evaluation of ad-hoc routing protocols

CSIR Research Space (South Africa)

Johnson, D

2007-09-01

Full Text Available to the source, to the Route Request packet. It retains the destination sequence number feature of AODV but HELLO packets are an optional feature and are normally left out by default. It also does away with the gratuitous RREP feature of AODV. Routing... spiral algorithm makes a decision to rebroadcast the packet or not and Fig. 5. confirms this. DYMO shows the least amount of routing traffic due to its lack of HELLO packets. This is also due to no further routing packets being transmitted once...

Self-Configuration and Self-Optimization Process in Heterogeneous Wireless Networks

Directory of Open Access Journals (Sweden)

Eduardo Camponogara

2010-12-01

Full Text Available Self-organization in Wireless Mesh Networks (WMN is an emergent research area, which is becoming important due to the increasing number of nodes in a network. Consequently, the manual configuration of nodes is either impossible or highly costly. So it is desirable for the nodes to be able to configure themselves. In this paper, we propose an alternative architecture for self-organization of WMN based on Optimized Link State Routing Protocol (OLSR and the ad hoc on demand distance vector (AODV routing protocols as well as using the technology of software agents. We argue that the proposed self-optimization and self-configuration modules increase the throughput of network, reduces delay transmission and network load, decreases the traffic of HELLO messages according to network’s scalability. By simulation analysis, we conclude that the self-optimization and self-configuration mechanisms can significantly improve the performance of OLSR and AODV protocols in comparison to the baseline protocols analyzed.

Self-Configuration and Self-Optimization Process in Heterogeneous Wireless Networks

Science.gov (United States)

Guardalben, Lucas; Villalba, Luis Javier García; Buiati, Fábio; Sobral, João Bosco Mangueira; Camponogara, Eduardo

2011-01-01

Self-organization in Wireless Mesh Networks (WMN) is an emergent research area, which is becoming important due to the increasing number of nodes in a network. Consequently, the manual configuration of nodes is either impossible or highly costly. So it is desirable for the nodes to be able to configure themselves. In this paper, we propose an alternative architecture for self-organization of WMN based on Optimized Link State Routing Protocol (OLSR) and the ad hoc on demand distance vector (AODV) routing protocols as well as using the technology of software agents. We argue that the proposed self-optimization and self-configuration modules increase the throughput of network, reduces delay transmission and network load, decreases the traffic of HELLO messages according to network’s scalability. By simulation analysis, we conclude that the self-optimization and self-configuration mechanisms can significantly improve the performance of OLSR and AODV protocols in comparison to the baseline protocols analyzed. PMID:22346584

A FSA Model for Performance Evaluation over Mobile Ad Hoc Networks with Low Traffic Volume

Directory of Open Access Journals (Sweden)

Heng LUO

2014-07-01

Full Text Available A Mobile Ad hoc network (MANET, which is composed of nodes that are able to move arbitrarily, differs from a direct connection network in the way that it is multi-hopping and self- organizing and thus able to operate without the help of prefixed infrastructures. However, problems such as unfavorable wireless links and dynamic topology are challenging, resulting in the proposal of a collection of routing protocols for MANETs. Nevertheless the performance of protocols may deteriorate dramatically as deployment scenario changes due to the application dependent philosophy behind algorithms. In this paper, the performance evaluation problem for MANETs and is explored and a novel performance ranking model, termed FSA, is proposed. For simplicity but without loss of generality, the performance of two routing protocols DSDV and DSR are studies. The FSA is able to rank the performance of DSDV and DSR depending on the average value and standard deviation results. Extensive simulations show that an overall 20.74 %, at most, gain may be achieved based on the FSA model.

Model checking mobile ad hoc networks

NARCIS (Netherlands)

Ghassemi, Fatemeh; Fokkink, Wan

2016-01-01

Modeling arbitrary connectivity changes within mobile ad hoc networks (MANETs) makes application of automated formal verification challenging. We use constrained labeled transition systems as a semantic model to represent mobility. To model check MANET protocols with respect to the underlying

Link mellem autisme og MFR-vaccine er dårlig videnskab

DEFF Research Database (Denmark)

Ramsøy, Thomas Z.

2010-01-01

En meget omdiskuteret frygt for en sammenhæng mellem MFR-vaccinen og autisme er for nylig manet til jorden......En meget omdiskuteret frygt for en sammenhæng mellem MFR-vaccinen og autisme er for nylig manet til jorden...

Decentralized position verification in geographic ad hoc routing

NARCIS (Netherlands)

Leinmüller, Tim; Schoch, Elmar; Kargl, Frank; Maihöfer, Christian

Inter-vehicle communication is regarded as one of the major applications of mobile ad hoc networks (MANETs). Compared to MANETs or wireless sensor networks (WSNs), these so-called vehicular ad hoc networks (VANETs) have unique requirements on network protocols. The requirements result mainly from

Adaptive, Tactical Mesh Networking: Control Base MANET Model

Science.gov (United States)

2010-09-01

pp. 316–320 Available: IEEE Xplore , http://ieeexplore.ieee.org [Accessed: June 9, 2010]. [5] N. Sidiropoulos, “Multiuser Transmit Beamforming...Mobile Mesh Segments of TNT Testbed .......... 11 Figure 5. Infrastructure and Ad Hoc Mode of IEEE 802.11................................ 13 Figure...6. The Power Spectral Density of OFDM................................................ 14 Figure 7. A Typical IEEE 802.16 Network

A New Intrusion Detection System Based on KNN Classification Algorithm in Wireless Sensor Network

Directory of Open Access Journals (Sweden)

Wenchao Li

2014-01-01

abnormal nodes from normal nodes by observing their abnormal behaviors, and we analyse parameter selection and error rate of the intrusion detection system. The paper elaborates on the design and implementation of the detection system. This system has achieved efficient, rapid intrusion detection by improving the wireless ad hoc on-demand distance vector routing protocol (Ad hoc On-Demand Distance the Vector Routing, AODV. Finally, the test results show that: the system has high detection accuracy and speed, in accordance with the requirement of wireless sensor network intrusion detection.

Security-Based Mechanism for Proactive Routing Schema Using Game Theory Model

Directory of Open Access Journals (Sweden)

Hicham Amraoui

2016-01-01

Full Text Available Game theory may offer a useful mechanism to address many problems in mobile ad hoc networks (MANETs. One of the key concepts in the research field of such networks with Optimized Link State Routing Protocol (OLSR is the security problem. Relying on applying game theory to study this problem, we consider two strategies during this suggested model: cooperate and not-cooperate. However, in such networks, it is not easy to identify different actions of players. In this paper, we have essentially been inspired from recent advances provided in game theory to propose a new model for security in MANETs. Our proposal presents a powerful tool with a large number of players where interactions are played multiple times. Moreover, each node keeps a cooperation rate (CR record of other nodes to cope with the behaviors and mitigate aggregate effect of other malicious devices. Additionally, our suggested security mechanism does not only take into consideration security requirements, but also take into account system resources and network performances. The simulation results using Network Simulator 3 are presented to illustrate the effectiveness of the proposal.

Exploiting Mobile Ad Hoc Networking and Knowledge Generation to Achieve Ambient Intelligence

Directory of Open Access Journals (Sweden)

Anna Lekova

2012-01-01

Full Text Available Ambient Intelligence (AmI joins together the fields of ubiquitous computing and communications, context awareness, and intelligent user interfaces. Energy, fault-tolerance, and mobility are newly added dimensions of AmI. Within the context of AmI the concept of mobile ad hoc networks (MANETs for “anytime and anywhere” is likely to play larger roles in the future in which people are surrounded and supported by small context-aware, cooperative, and nonobtrusive devices that will aid our everyday life. The connection between knowledge generation and communication ad hoc networking is symbiotic—knowledge generation utilizes ad hoc networking to perform their communication needs, and MANETs will utilize the knowledge generation to enhance their network services. The contribution of the present study is a distributed evolving fuzzy modeling framework (EFMF to observe and categorize relationships and activities in the user and application level and based on that social context to take intelligent decisions about MANETs service management. EFMF employs unsupervised online one-pass fuzzy clustering method to recognize nodes' mobility context from social scenario traces and ubiquitously learn “friends” and “strangers” indirectly and anonymously.

Peer-to-peer over mobile ad hoc networks (Chapter 11)

NARCIS (Netherlands)

Qadri, N.N.; Liotta, A.; Pierre, S.

2010-01-01

In this chapter we review various approaches for the convergence of Peer-to-Peer (P2P) and Mobile Ad hoc Networks (MANETs), identifying strengths and weaknesses, and putting things in perspective. P2P and MANETs are among the most active research topics in pervasive computing. The convergence of P2P

LBMR: Load-Balanced Multipath Routing for Wireless Data-Intensive Transmission in Real-Time Medical Monitoring.

Science.gov (United States)

Tseng, Chinyang Henry

2016-05-31

In wireless networks, low-power Zigbee is an excellent network solution for wireless medical monitoring systems. Medical monitoring generally involves transmission of a large amount of data and easily causes bottleneck problems. Although Zigbee's AODV mesh routing provides extensible multi-hop data transmission to extend network coverage, it originally does not, and needs to support some form of load balancing mechanism to avoid bottlenecks. To guarantee a more reliable multi-hop data transmission for life-critical medical applications, we have developed a multipath solution, called Load-Balanced Multipath Routing (LBMR) to replace Zigbee's routing mechanism. LBMR consists of three main parts: Layer Routing Construction (LRC), a Load Estimation Algorithm (LEA), and a Route Maintenance (RM) mechanism. LRC assigns nodes into different layers based on the node's distance to the medical data gateway. Nodes can have multiple next-hops delivering medical data toward the gateway. All neighboring layer-nodes exchange flow information containing current load, which is the used by the LEA to estimate future load of next-hops to the gateway. With LBMR, nodes can choose the neighbors with the least load as the next-hops and thus can achieve load balancing and avoid bottlenecks. Furthermore, RM can detect route failures in real-time and perform route redirection to ensure routing robustness. Since LRC and LEA prevent bottlenecks while RM ensures routing fault tolerance, LBMR provides a highly reliable routing service for medical monitoring. To evaluate these accomplishments, we compare LBMR with Zigbee's AODV and another multipath protocol, AOMDV. The simulation results demonstrate LBMR achieves better load balancing, less unreachable nodes, and better packet delivery ratio than either AODV or AOMDV.

Analytical approach to cross-layer protocol optimization in wireless sensor networks

Science.gov (United States)

Hortos, William S.

2008-04-01

In the distributed operations of route discovery and maintenance, strong interaction occurs across mobile ad hoc network (MANET) protocol layers. Quality of service (QoS) requirements of multimedia service classes must be satisfied by the cross-layer protocol, along with minimization of the distributed power consumption at nodes and along routes to battery-limited energy constraints. In previous work by the author, cross-layer interactions in the MANET protocol are modeled in terms of a set of concatenated design parameters and associated resource levels by multivariate point processes (MVPPs). Determination of the "best" cross-layer design is carried out using the optimal control of martingale representations of the MVPPs. In contrast to the competitive interaction among nodes in a MANET for multimedia services using limited resources, the interaction among the nodes of a wireless sensor network (WSN) is distributed and collaborative, based on the processing of data from a variety of sensors at nodes to satisfy common mission objectives. Sensor data originates at the nodes at the periphery of the WSN, is successively transported to other nodes for aggregation based on information-theoretic measures of correlation and ultimately sent as information to one or more destination (decision) nodes. The "multimedia services" in the MANET model are replaced by multiple types of sensors, e.g., audio, seismic, imaging, thermal, etc., at the nodes; the QoS metrics associated with MANETs become those associated with the quality of fused information flow, i.e., throughput, delay, packet error rate, data correlation, etc. Significantly, the essential analytical approach to MANET cross-layer optimization, now based on the MVPPs for discrete random events occurring in the WSN, can be applied to develop the stochastic characteristics and optimality conditions for cross-layer designs of sensor network protocols. Functional dependencies of WSN performance metrics are described in

Proactive Alleviation Procedure to Handle Black Hole Attack and Its Version

Science.gov (United States)

Babu, M. Rajesh; Dian, S. Moses; Chelladurai, Siva; Palaniappan, Mathiyalagan

2015-01-01

The world is moving towards a new realm of computing such as Internet of Things. The Internet of Things, however, envisions connecting almost all objects within the world to the Internet by recognizing them as smart objects. In doing so, the existing networks which include wired, wireless, and ad hoc networks should be utilized. Moreover, apart from other networks, the ad hoc network is full of security challenges. For instance, the MANET (mobile ad hoc network) is susceptible to various attacks in which the black hole attacks and its versions do serious damage to the entire MANET infrastructure. The severity of this attack increases, when the compromised MANET nodes work in cooperation with each other to make a cooperative black hole attack. Therefore this paper proposes an alleviation procedure which consists of timely mandate procedure, hole detection algorithm, and sensitive guard procedure to detect the maliciously behaving nodes. It has been observed that the proposed procedure is cost-effective and ensures QoS guarantee by assuring resource availability thus making the MANET appropriate for Internet of Things. PMID:26495430

Proactive Alleviation Procedure to Handle Black Hole Attack and Its Version.

Science.gov (United States)

Babu, M Rajesh; Dian, S Moses; Chelladurai, Siva; Palaniappan, Mathiyalagan

2015-01-01

The world is moving towards a new realm of computing such as Internet of Things. The Internet of Things, however, envisions connecting almost all objects within the world to the Internet by recognizing them as smart objects. In doing so, the existing networks which include wired, wireless, and ad hoc networks should be utilized. Moreover, apart from other networks, the ad hoc network is full of security challenges. For instance, the MANET (mobile ad hoc network) is susceptible to various attacks in which the black hole attacks and its versions do serious damage to the entire MANET infrastructure. The severity of this attack increases, when the compromised MANET nodes work in cooperation with each other to make a cooperative black hole attack. Therefore this paper proposes an alleviation procedure which consists of timely mandate procedure, hole detection algorithm, and sensitive guard procedure to detect the maliciously behaving nodes. It has been observed that the proposed procedure is cost-effective and ensures QoS guarantee by assuring resource availability thus making the MANET appropriate for Internet of Things.

PERFORMANCE ANALYSIS OF DSR ROUTING PROTOCOL UNDER ENERGY BASED SELFISH ATTACK IN MOBILE AD HOC NETWORKS

Directory of Open Access Journals (Sweden)

T.V.P.Sundararajan

2010-06-01

Full Text Available Mobile Ad hoc Networks (MANETs rely on the cooperation of all participating nodes to provide the fundamental operations such as routing and data forwarding. However, due to the open structure and scarcely available battery-based energy, node misbehaviors may exist.[1]. One such routing misbehavior is that some selfish nodes will participate in the route discovery and maintenance processes but refuse to forward data packets. This paper pointed out Energy based selfish nodes (EBSN where these selfish nodes tend to use the network but do not cooperate, saving battery life for their own communications [2],[3]. We present a simulation study of the effects of Energy based selfish nodes (EBSN on DSR routing protocol and its impact over network performance in terms of throughput and delay of a mobile ad hoc network where a defined percentage of nodes were misbehaving.

Verification of mobile ad hoc networks : an algebraic approach

NARCIS (Netherlands)

Ghassemi, F.; Fokkink, W.J.; Movaghar, A.

2011-01-01

We introduced Computed Network Process Theory to reason about protocols for mobile ad hoc networks (MANETs). Here we explore the applicability of our framework in two regards: model checking and equational reasoning. The operational semantics of our framework is based on constrained labeled

A LOOP-BASED APPROACH IN CLUSTERING AND ROUTING IN MOBILE AD HOC NETWORKS

Institute of Scientific and Technical Information of China (English)

Li Yanping; Wang Xin; Xue Xiangyang; C.K. Toh

2006-01-01

Although clustering is a convenient framework to enable traffic control and service support in Mobile Ad hoc NETworks (MANETs), it is seldom adopted in practice due to the additional traffic overhead it leads to for the resource limited ad hoc network. In order to address this problem, we proposed a loop-based approach to combine clustering and routing. By employing loop topologies, topology information is disseminated with a loop instead of a single node, which provides better robustness, and the nature of a loop that there are two paths between each pair of nodes within a loop suggests smart route recovery strategy. Our approach is composed of setup procedure, regular procedure and recovery procedure to achieve clustering, routing and emergent route recovering.

A model to improve the routing performance of Cognitive Radio Wireless Mesh Networks

Directory of Open Access Journals (Sweden)

Lesiba Morries Kola

2017-12-01

Full Text Available The increasing demand for broadband wireless technologies has led to the scarcity, inefficient utilization, and underutilization of the spectrum. The Cognitive Radio (CR technology has emerged as the promising solution which improves the utilization of the spectrum. However, routing is a challenge due to the dynamic nature of the CR networks. The link quality varies in space and time as nodes join and leave the network. The network connectivity is intermittent due to node mobility and the activities of the primary user. The spectrum aware, spectrum agile, and interference aware routing protocols are vital for the sturdiness of the network and efficient utilization of the resources. We propose an interference aware, spectrum aware, and agile extended Weighted Cumulative Expected Transmission Time (xWCETT routing protocol. The protocol integrates the features of the Ad-hoc On-demand Distance Vector (AODV and the weighted cumulative expected transmission time (WCETT routing protocols. The xWCETT was simulated using the Network Simulator 2 and its performance compared with the AODV and the WCETT routing protocols. The xWCETT was evaluated with respect to quality of service related metrics and the results show that it outperformed the AODV and WCETT routing protocols.

Improving Network Performance with Affinity based Mobility Model in Opportunistic Network

OpenAIRE

Suvadip Batabyal; Parama Bhaumik

2012-01-01

Opportunistic network is a type of Delay Tolerant Network which is characterized by intermittent connectivity amongst the nodes and communication largely depends upon the mobility of the participating nodes. The network being highly dynamic, traditional MANET protocols cannot be applied and the nodes must adhere to store-carry-forward mechanism. Nodes do not have the information about the network topology, number of participating nodes and the location of the destination node. Hence, message ...

Impressionistide vedurisuitsune Pariis

Index Scriptorium Estoniae

1998-01-01

Maikuu keskpaigani 1998 Musée d'Orsays olnud näitusest 'Manet, Monet & La Gare St. Lazare', mis 14. juunist avati Washingtoni Rahvusgaleriis. Näituse võtmeks oli St. Lazare'i raudteejaam, mida C. Monet on 11 korda maalinud. E. Manet'lt olid näitusel valdavalt Rue St. Petersbourg'i lähikonnast maalitud tööd

Sadhana | Indian Academy of Sciences

Indian Academy of Sciences (India)

Position based opportunistic routing (POR) is a stateless, robust, and reliable geographic routing protocol in Mobile AdHoc NETwork (MANET). The opportunistic routing embraces broadcast property of wireless channels and utilizes it for opportunistic forwarding. Both the malicious node behavior and the backupnodes' ...

A SURVEY ON DELAY AND NEIGHBOR NODE MONITORING BASED WORMHOLE ATTACK PREVENTION AND DETECTION

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Sudhir T Bagade

2016-12-01

Full Text Available In Mobile Ad-hoc Networks (MANET, network layer attacks, for example wormhole attacks, disrupt the network routing operations and can be used for data theft. Wormhole attacks are of two types: hidden and exposed wormhole. There are various mechanisms in literature which are used to prevent and detect wormhole attacks. In this paper, we survey wormhole prevention and detection techniques and present our critical observations for each. These techniques are based on cryptographic mechanisms, monitoring of packet transmission delay and control packet forwarding behavior of neighbor nodes. We compare the techniques using the following criteria- extra resources needed applicability to different network topologies and routing protocols, prevention/detection capability, etc. We conclude the paper with potential research directions.

A Dynamic Reputation Management System for Mobile Ad Hoc Networks

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Eric Chiejina

2015-04-01

Full Text Available Nodes in mobile ad hoc networks (MANETs are mandated to utilize their limited energy resources in forwarding routing control and data packets for other nodes. Since a MANET lacks a centralized administration and control, a node may decide to act selfishly, either by refusing to respond to route requests from other nodes or deceitfully by responding to some route requests, but dropping the corresponding data packets that are presented for forwarding. A significant increase in the presence of these misbehaving nodes in a MANET can subsequently degrade network performance. In this paper, we propose a dynamic reputation management system for detecting and isolating misbehaving nodes in MANETs. Our model employs a novel direct monitoring technique to evaluate the reputation of a node in the network, which ensures that nodes that expend their energy in transmitting data and routing control packets for others are allowed to carry out their network activities while the misbehaving nodes are detected and isolated from the network. Simulation results show that our model is effective at curbing and mitigating the effects of misbehaving nodes in the network.

Genetic based optimization for multicast routing algorithm for MANET

Indian Academy of Sciences (India)

three main principles of natural evolution: reproduction, natural selection and species .... For example, figure 3 shows a six-node network with node reachability shown by ... sion range of each node is 220 m using an Omni directional antenna.

Verification of Correspondence Assertions in a Calculus for Mobile Ad Hoc Networks

DEFF Research Database (Denmark)

Godskesen, Jens Christian; Huttel, Hans; Kühnrich, Morten

2009-01-01

are explicitly part of the syntax allowing dynamic extension using bound identifiers. In this semantic setting we study authentication of agents in MANET protocols. A safety property dealing with authentication correspondence assertions is defined. Later a dependent type and effect system is given...... protocol – a type check shows it is safe. To our knowledge this is the first type system for a MANET calculus doing that....

A Multi-User Game-Theoretical Multipath Routing Protocol to Send Video-Warning Messages over Mobile Ad Hoc Networks.

Science.gov (United States)

Mezher, Ahmad Mohamad; Igartua, Mónica Aguilar; de la Cruz Llopis, Luis J; Pallarès Segarra, Esteve; Tripp-Barba, Carolina; Urquiza-Aguiar, Luis; Forné, Jordi; Sanvicente Gargallo, Emilio

2015-04-17

The prevention of accidents is one of the most important goals of ad hoc networks in smart cities. When an accident happens, dynamic sensors (e.g., citizens with smart phones or tablets, smart vehicles and buses, etc.) could shoot a video clip of the accident and send it through the ad hoc network. With a video message, the level of seriousness of the accident could be much better evaluated by the authorities (e.g., health care units, police and ambulance drivers) rather than with just a simple text message. Besides, other citizens would be rapidly aware of the incident. In this way, smart dynamic sensors could participate in reporting a situation in the city using the ad hoc network so it would be possible to have a quick reaction warning citizens and emergency units. The deployment of an efficient routing protocol to manage video-warning messages in mobile Ad hoc Networks (MANETs) has important benefits by allowing a fast warning of the incident, which potentially can save lives. To contribute with this goal, we propose a multipath routing protocol to provide video-warning messages in MANETs using a novel game-theoretical approach. As a base for our work, we start from our previous work, where a 2-players game-theoretical routing protocol was proposed to provide video-streaming services over MANETs. In this article, we further generalize the analysis made for a general number of N players in the MANET. Simulations have been carried out to show the benefits of our proposal, taking into account the mobility of the nodes and the presence of interfering traffic. Finally, we also have tested our approach in a vehicular ad hoc network as an incipient start point to develop a novel proposal specifically designed for VANETs.

A Multi-User Game-Theoretical Multipath Routing Protocol to Send Video-Warning Messages over Mobile Ad Hoc Networks

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Ahmad Mohamad Mezher

2015-04-01

Full Text Available The prevention of accidents is one of the most important goals of ad hoc networks in smart cities. When an accident happens, dynamic sensors (e.g., citizens with smart phones or tablets, smart vehicles and buses, etc. could shoot a video clip of the accident and send it through the ad hoc network. With a video message, the level of seriousness of the accident could be much better evaluated by the authorities (e.g., health care units, police and ambulance drivers rather than with just a simple text message. Besides, other citizens would be rapidly aware of the incident. In this way, smart dynamic sensors could participate in reporting a situation in the city using the ad hoc network so it would be possible to have a quick reaction warning citizens and emergency units. The deployment of an efficient routing protocol to manage video-warning messages in mobile Ad hoc Networks (MANETs has important benefits by allowing a fast warning of the incident, which potentially can save lives. To contribute with this goal, we propose a multipath routing protocol to provide video-warning messages in MANETs using a novel game-theoretical approach. As a base for our work, we start from our previous work, where a 2-players game-theoretical routing protocol was proposed to provide video-streaming services over MANETs. In this article, we further generalize the analysis made for a general number of N players in the MANET. Simulations have been carried out to show the benefits of our proposal, taking into account the mobility of the nodes and the presence of interfering traffic. Finally, we also have tested our approach in a vehicular ad hoc network as an incipient start point to develop a novel proposal specifically designed for VANETs.

A Conceptual Framework for Representing Human Behavior Characteristics in a System of Systems Agent-Based Survivability Simulation

Science.gov (United States)

2010-11-22

MANET system to reorganize. Soni and Dawra (2007) note that “self-organizing systems of agents with emergent system-level functions offer these...2007 IEEE International Conference on Telecommunications and Malaysia International Conference on Communications, 14-17. Burt, R. (1992). Structural...Bombay. Soni , D and Dawra, S (2007). AI System in (12th WSEAS Int. Conf. on Applied Mathematics, Cairo, Egypt, December 29-31, 2007 401. Sridhar

Designing Robust and Resilient Tactical MANETs

Science.gov (United States)

2014-09-25

0. doi: B. Tan , J. Ni, R. Srikant. Q-CSMA: Queue-Length-Based CSMA/CA Algorithms for Achieving Maximum Throughput and Low Delay in Wireless Networks...INFOCOM 2012 Mini-Conference. 01-JAN-12, . : , J. Katz , Y. Lindell. Aggregate Message Authentication Codes, RSA 2008 . 01-JAN-08, . : , J. Ni, Bo Tan ...Haas, Yih-Chun Hu, Nicola Laurenti. Low-Cost Mitigation of Privacy Loss due to Radiometric Identification, Eighth ACM International Workshop on

Compromises Between Quality of Service Metrics and Energy Consumption of Hierarchical and Flat Routing Protocols for Wireless Sensors Network

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Abdelbari BEN YAGOUTA

2016-11-01

Full Text Available Wireless Sensor Network (WSN is wireless network composed of spatially distributed and tiny autonomous nodes, which cooperatively monitor physical or environmental conditions. Among the concerns of these networks is prolonging the lifetime by saving nodes energy. There are several protocols specially designed for WSNs based on energy conservation. However, many WSNs applications require QoS (Quality of Service criteria, such as latency, reliability and throughput. In this paper, we will compare three routing protocols for wireless sensors network LEACH (Low Energy Adaptive Clustering Hierarchy, AODV (Ad hoc on demand Distance Vector and LABILE (Link Quality-Based Lexical Routing using Castalia simulator in terms of energy consumption, throughput, reliability and latency time of packets received by sink under different conditions to determinate the best configurations that offers the most suitable compromises between energy conservation and all QoS metrics for each routing protocols. The results show that, the best configurations that offer the suitable compromises between energy conservation and all QoS metrics is a large number of deployed nodes with low packet rate for LEACH (300 nodes and 1 packet/s, a medium number of deployed nodes with low packet rate For AODV (100 nodes and 1 packet/s and a very low nodes density with low packet rate for LABILE (50 nodes and 1 packet/s.

Performance analysis of routing protocols for IoT

Science.gov (United States)

Manda, Sridhar; Nalini, N.

2018-04-01

Internet of Things (IoT) is an arrangement of advancements that are between disciplinary. It is utilized to have compelling combination of both physical and computerized things. With IoT physical things can have personal virtual identities and participate in distributed computing. Realization of IoT needs the usage of sensors based on the sector for which IoT is integrated. For instance, in healthcare domain, IoT needs to have integration with wearable sensors used by patients. As sensor devices produce huge amount of data, often called big data, there should be efficient routing protocols in place. To the extent remote systems is worried there are some current protocols, for example, OLSR, DSR and AODV. It additionally tosses light into Trust based routing protocol for low-power and lossy systems (TRPL) for IoT. These are broadly utilized remote directing protocols. As IoT is developing round the corner, it is basic to investigate routing protocols that and evaluate their execution regarding throughput, end to end delay, and directing overhead. The execution experiences can help in settling on very much educated choices while incorporating remote systems with IoT. In this paper, we analyzed different routing protocols and their performance is compared. It is found that AODV showed better performance than other routing protocols aforementioned.

Optimized energy-delay sub-network routing protocol development and implementation for wireless sensor networks

International Nuclear Information System (INIS)

Fonda, James W; Zawodniok, Maciej; Jagannathan, S; Watkins, Steve E

2008-01-01

The development and the implementation issues of a reactive optimized energy-delay sub-network routing (OEDSR) protocol for wireless sensor networks (WSN) are introduced and its performance is contrasted with the popular ad hoc on-demand distance vector (AODV) routing protocol. Analytical results illustrate the performance of the proposed OEDSR protocol, while experimental results utilizing a hardware testbed under various scenarios demonstrate improvements in energy efficiency of the OEDSR protocol. A hardware platform constructed at the University of Missouri-Rolla (UMR), now the Missouri University of Science and Technology (MST), based on the Generation 4 Smart Sensor Node (G4-SSN) prototyping platform is also described. Performance improvements are shown in terms of end-to-end (E2E) delay, throughput, route-set-up time and drop rates and energy usage is given for three topologies, including a mobile topology. Additionally, results from the hardware testbed provide valuable lessons for network deployments. Under testing OEDSR provides a factor of ten improvement in the energy used in the routing session and extends network lifetime compared to AODV. Depletion experiments show that the time until the first node failure is extended by a factor of three with the network depleting and network lifetime is extended by 6.7%

Energy-Efficient Cluster Based Routing Protocol in Mobile Ad Hoc Networks Using Network Coding

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Srinivas Kanakala

2014-01-01

Full Text Available In mobile ad hoc networks, all nodes are energy constrained. In such situations, it is important to reduce energy consumption. In this paper, we consider the issues of energy efficient communication in MANETs using network coding. Network coding is an effective method to improve the performance of wireless networks. COPE protocol implements network coding concept to reduce number of transmissions by mixing the packets at intermediate nodes. We incorporate COPE into cluster based routing protocol to further reduce the energy consumption. The proposed energy-efficient coding-aware cluster based routing protocol (ECCRP scheme applies network coding at cluster heads to reduce number of transmissions. We also modify the queue management procedure of COPE protocol to further improve coding opportunities. We also use an energy efficient scheme while selecting the cluster head. It helps to increase the life time of the network. We evaluate the performance of proposed energy efficient cluster based protocol using simulation. Simulation results show that the proposed ECCRP algorithm reduces energy consumption and increases life time of the network.

GA-DoSLD: Genetic Algorithm Based Denial-of-Sleep Attack Detection in WSN

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Mahalakshmi Gunasekaran

2017-01-01

Full Text Available Denial-of-sleep (DoSL attack is a special category of denial-of-service attack that prevents the battery powered sensor nodes from going into the sleep mode, thus affecting the network performance. The existing schemes used for the DoSL attack detection do not provide an optimal energy conservation and key pairing operation. Hence, in this paper, an efficient Genetic Algorithm (GA based denial-of-sleep attack detection (GA-DoSLD algorithm is suggested for analyzing the misbehaviors of the nodes. The suggested algorithm implements a Modified-RSA (MRSA algorithm in the base station (BS for generating and distributing the key pair among the sensor nodes. Before sending/receiving the packets, the sensor nodes determine the optimal route using Ad Hoc On-Demand Distance Vector Routing (AODV protocol and then ensure the trustworthiness of the relay node using the fitness calculation. The crossover and mutation operations detect and analyze the methods that the attackers use for implementing the attack. On determining an attacker node, the BS broadcasts the blocked information to all the other sensor nodes in the network. Simulation results prove that the suggested algorithm is optimal compared to the existing algorithms such as X-MAC, ZKP, and TE2P schemes.

Quality-of-Service Routing Using Path and Power Aware Techniques in Mobile Ad Hoc Networks

Directory of Open Access Journals (Sweden)

R. Asokan

2008-01-01

Full Text Available Mobile ad hoc network (MANET is a collection of wireless mobile hosts dynamically forming a temporary network without the aid of any existing established infrastructure. Quality of service (QoS is a set of service requirements that needs to be met by the network while transporting a packet stream from a source to its destination. QoS support MANETs is a challenging task due to the dynamic topology and limited resources. The main objective of this paper is to enhance the QoS routing for MANET using temporally ordered routing algorithm (TORA with self-healing and optimized routing techniques (SHORT. SHORT improves routing optimality by monitoring routing paths continuously and redirecting the path whenever a shortcut path is available. In this paper, the performance comparison of TORA and TORA with SHORT has been analyzed using network simulator for various parameters. TORA with SHORT enhances performance of TORA in terms of throughput, packet loss, end-to-end delay, and energy.

A Cross-Layer Route Discovery Framework for Mobile Ad Hoc Networks

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Wu Jieyi

2005-01-01

Full Text Available Most reactive routing protocols in MANETs employ a random delay between rebroadcasting route requests (RREQ in order to avoid "broadcast storms." However this can lead to problems such as "next hop racing" and "rebroadcast redundancy." In addition to this, existing routing protocols for MANETs usually take a single routing strategy for all flows. This may lead to inefficient use of resources. In this paper we propose a cross-layer route discovery framework (CRDF to address these problems by exploiting the cross-layer information. CRDF solves the above problems efficiently and enables a new technique: routing strategy automation (RoSAuto. RoSAuto refers to the technique that each source node automatically decides the routing strategy based on the application requirements and each intermediate node further adapts the routing strategy so that the network resource usage can be optimized. To demonstrate the effectiveness and the efficiency of CRDF, we design and evaluate a macrobian route discovery strategy under CRDF.

Scalable Lunar Surface Networks and Adaptive Orbit Access

Science.gov (United States)

Wang, Xudong

2015-01-01

Teranovi Technologies, Inc., has developed innovative network architecture, protocols, and algorithms for both lunar surface and orbit access networks. A key component of the overall architecture is a medium access control (MAC) protocol that includes a novel mechanism of overlaying time division multiple access (TDMA) and carrier sense multiple access with collision avoidance (CSMA/CA), ensuring scalable throughput and quality of service. The new MAC protocol is compatible with legacy Institute of Electrical and Electronics Engineers (IEEE) 802.11 networks. Advanced features include efficiency power management, adaptive channel width adjustment, and error control capability. A hybrid routing protocol combines the advantages of ad hoc on-demand distance vector (AODV) routing and disruption/delay-tolerant network (DTN) routing. Performance is significantly better than AODV or DTN and will be particularly effective for wireless networks with intermittent links, such as lunar and planetary surface networks and orbit access networks.

Power-Aware Intrusion Detection in Mobile Ad Hoc Networks

Science.gov (United States)

Şen, Sevil; Clark, John A.; Tapiador, Juan E.

Mobile ad hoc networks (MANETs) are a highly promising new form of networking. However they are more vulnerable to attacks than wired networks. In addition, conventional intrusion detection systems (IDS) are ineffective and inefficient for highly dynamic and resource-constrained environments. Achieving an effective operational MANET requires tradeoffs to be made between functional and non-functional criteria. In this paper we show how Genetic Programming (GP) together with a Multi-Objective Evolutionary Algorithm (MOEA) can be used to synthesise intrusion detection programs that make optimal tradeoffs between security criteria and the power they consume.

Intelligent self-organization methods for wireless ad hoc sensor networks based on limited resources

Science.gov (United States)

Hortos, William S.

2006-05-01

A wireless ad hoc sensor network (WSN) is a configuration for area surveillance that affords rapid, flexible deployment in arbitrary threat environments. There is no infrastructure support and sensor nodes communicate with each other only when they are in transmission range. To a greater degree than the terminals found in mobile ad hoc networks (MANETs) for communications, sensor nodes are resource-constrained, with limited computational processing, bandwidth, memory, and power, and are typically unattended once in operation. Consequently, the level of information exchange among nodes, to support any complex adaptive algorithms to establish network connectivity and optimize throughput, not only deplete those limited resources and creates high overhead in narrowband communications, but also increase network vulnerability to eavesdropping by malicious nodes. Cooperation among nodes, critical to the mission of sensor networks, can thus be disrupted by the inappropriate choice of the method for self-organization. Recent published contributions to the self-configuration of ad hoc sensor networks, e.g., self-organizing mapping and swarm intelligence techniques, have been based on the adaptive control of the cross-layer interactions found in MANET protocols to achieve one or more performance objectives: connectivity, intrusion resistance, power control, throughput, and delay. However, few studies have examined the performance of these algorithms when implemented with the limited resources of WSNs. In this paper, self-organization algorithms for the initiation, operation and maintenance of a network topology from a collection of wireless sensor nodes are proposed that improve the performance metrics significant to WSNs. The intelligent algorithm approach emphasizes low computational complexity, energy efficiency and robust adaptation to change, allowing distributed implementation with the actual limited resources of the cooperative nodes of the network. Extensions of the

A MODIFIED ROUTE DISCOVERY APPROACH FOR DYNAMIC SOURCE ROUTING (DSR PROTOCOL IN MOBILE AD-HOC NETWORKS

Directory of Open Access Journals (Sweden)

Alaa Azmi Allahham

2017-02-01

Full Text Available Mobile Ad-hoc networks (MANETs involved in many applications, whether commercial or military because of their characteristics that do not depend on the infrastructure as well as the freedom movement of their elements, but in return has caused this random mobility of the nodes many of the challenges, where the routing is considered one of these challenges. There are many types of routing protocols that operate within MANET networks, which responsible for finding paths between the source and destination nodes with the modernization of these paths which are constantly changing due to the dynamic topology of the network stemming from the constant random movement of the nodes. The DSR (Dynamic Source Routing routing protocol algorithm is one of these routing protocols which consist of two main stages; route discovery and maintenance, where the route discovery algorithm operates based on blind flooding of request messages. blind flooding is considered as the most well known broadcasting mechanism, it is inefficient in terms of communication and resource utilization, which causing increasing the probability of collisions, repeating send several copies of the same message, as well as increasing the delay. Hence, a new mechanism in route discovery stage and in caching the routes in DSR algorithm according to the node's location in the network and the direction of the broadcast is proposed for better performance especially in terms of delay as well as redundant packets rate. The implementation of proposed algorithms showed positive results in terms of delay, overhead, and improve the performance of MANETs in general.

An Agent-Based Approach To Nodes Misbehaviour Detection In Mobile Ad-Hoc Networks

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Otor Samera U.

2017-02-01

Full Text Available Existing Misbehaviour Detection Systems in Mobile Ad-hoc Networks MANETs are challenged with routing overhead and high latency resulting from complexity and failure to isolate and block misbehaving nodes for the reason that it is difficult to detect them as they participate fully in route finding. In this work a Mobile Agent-Based Acknowledgement scheme MAACK was formulated to address this problem using an object oriented algorithm deployed to report misbehaving nodes to the source and destination by registering the Internet Protocol IP address of misbehaving nodes in their header. The scheme was simulated using Network Simulator-3 NS-3 and results benchmarked with an existing scheme the Enhanced Adaptive Acknowledgment EAACK using packet delivery ratio routing overhead and latency as performance metrics in the two scenarios. The results showed that the MAACK paradigm guaranteed a higher packet delivery ratio lower latency and routing overhead than the EAACK scheme. The model can be adapted by Ad-Hoc network protocol developers.

Influence of PbBi environment on the low-cycle fatigue behavior of SNS target container materials

International Nuclear Information System (INIS)

Kalkhof, D.; Grosse, M.

2003-01-01

The low-cycle fatigue (LCF) behavior of the stainless steel 316L and the 10.5Cr-steel Manet-II was investigated at 260 deg. C in air and in stagnant lead-bismuth (PbBi). At low-strain levels, the fatigue lives for 316L in PbBi and air were comparable. At total strain amplitudes of 0.50% and higher a weak influence of PbBi was observed. In contrast to 316L, the results of LCF tests for Manet-II in PbBi showed a significant reduction of lifetime for all applied strain amplitudes. In the worst case the cycle number to crack initiation was reduced by a factor of ∼7 compared with the comparable test in air. For the low-strain amplitude of 0.30%, fatigue tests conducted at a frequency of 0.1 Hz had shorter fatigue lives than at a frequency of 1.0 Hz. For Manet-II the crack propagation in PbBi was much faster than in air, and failure immediate followed the formation of the first macroscopic crack

Achieving sink node anonymity in tactical wireless sensor networks using a reactive routing protocol

Science.gov (United States)

2017-06-01

node anonymity, base station anonymity, Wireless Sensor Networks (WSN), Mobile Ad hoc Network (MANET), Lightweight Ad hoc On-Demand – Next Generation ... Generation (LOADng) reactive-routing protocol to achieve anonymity. This modified protocol prevents an attacker from identifying the sink node without...within the constraints of WSN communication protocols, specifically IEEE 802.15.4. We use and modify the Lightweight Ad hoc On-Demand – Next Generation

Construct mine environment monitoring system based on wireless mesh network

Science.gov (United States)

Chen, Xin; Ge, Gengyu; Liu, Yinmei; Cheng, Aimin; Wu, Jun; Fu, Jun

2018-04-01

The system uses wireless Mesh network as a network transmission medium, and strive to establish an effective and reliable underground environment monitoring system. The system combines wireless network technology and embedded technology to monitor the internal data collected in the mine and send it to the processing center for analysis and environmental assessment. The system can be divided into two parts: the main control network module and the data acquisition terminal, and the SPI bus technology is used for mutual communication between them. Multi-channel acquisition and control interface design Data acquisition and control terminal in the analog signal acquisition module, digital signal acquisition module, and digital signal output module. The main control network module running Linux operating system, in which the transplant SPI driver, USB card driver and AODV routing protocol. As a result, the internal data collection and reporting of the mine are realized.

Handbook on theoretical and algorithmic aspects of sensor, ad hoc wireless, and peer-to-peer networks

CERN Document Server

Wu, Jie

2005-01-01

PrefaceAD HOC WIRELESS NETWORKSA Modular Cross Layer Architecture for Ad Hoc Networks, M. Conti, J. Crowcroft, G. Maselli, and G. TuriRouting Scalability in MANETs, J. Eriksson, S. Krishnamurthy and M. FaloutsosUniformly Distributed Algorithm for Virtual Backbone Routing in Ad Hoc Wireless Networks, D.S. KimMaximum Necessary Hop Count for Packet Routing in MANET, X. Chen and J. ShenEfficient Strategyproof Multicast in Selfish Wireless Networks, X.-Yang LiGeocasting in Ad Hoc and Sensor Networks, I. StojmenovicTopology Control for Ad hoc Networks: Present Solutions and Open Issues, C.-C. Shen a

Two-terminal reliability of a mobile ad hoc network under the asymptotic spatial distribution of the random waypoint model

International Nuclear Information System (INIS)

Chen, Binchao; Phillips, Aaron; Matis, Timothy I.

2012-01-01

The random waypoint (RWP) mobility model is frequently used in describing the movement pattern of mobile users in a mobile ad hoc network (MANET). As the asymptotic spatial distribution of nodes under a RWP model exhibits central tendency, the two-terminal reliability of the MANET is investigated as a function of the source node location. In particular, analytical expressions for one and two hop connectivities are developed as well as an efficient simulation methodology for two-terminal reliability. A study is then performed to assess the effect of nodal density and network topology on network reliability.

Adaptive MANET Multipath Routing Algorithm Based on the Simulated Annealing Approach

Directory of Open Access Journals (Sweden)

Sungwook Kim

2014-01-01

Full Text Available Mobile ad hoc network represents a system of wireless mobile nodes that can freely and dynamically self-organize network topologies without any preexisting communication infrastructure. Due to characteristics like temporary topology and absence of centralized authority, routing is one of the major issues in ad hoc networks. In this paper, a new multipath routing scheme is proposed by employing simulated annealing approach. The proposed metaheuristic approach can achieve greater and reciprocal advantages in a hostile dynamic real world network situation. Therefore, the proposed routing scheme is a powerful method for finding an effective solution into the conflict mobile ad hoc network routing problem. Simulation results indicate that the proposed paradigm adapts best to the variation of dynamic network situations. The average remaining energy, network throughput, packet loss probability, and traffic load distribution are improved by about 10%, 10%, 5%, and 10%, respectively, more than the existing schemes.

A miniaturized test method for the mechanical characterization of structural materials for fusion reactors

International Nuclear Information System (INIS)

Gondi, P.; Montanari, R.; Sili, A.

1996-01-01

This work deals with a non-destructive method for mechanical tests which is based on the indentation of materials at a constant rate by means of a cylinder with a small radius and penetrating flat surface. The load versus penetration depth curves obtained using this method have shown correspondences with those of tensile tests and have given indications about the mechanical properties on a reduced scale. In this work penetration tests have been carried out on various kinds of Cr martensitic steels (MANET-2, BATMAN and modified F82H) which are of interest for first wall and structural applications in future fusion reactors. The load versus penetration depth curves have been examined with reference to data obtained in tensile tests and to microhardness measurements. Penetration tests have been performed at various temperature (from -180 to 100 C). Conclusions, which can be drawn for the ductile to brittle transition, are discussed for MANET-2 steel. Preliminary results obtained on BATMAN and modified F82H steels are reported. The characteristics of the indenter imprints have been studied by scanning electron microscopy. (orig.)

Delay and cost performance analysis of the diffie-hellman key exchange protocol in opportunistic mobile networks

Science.gov (United States)

Soelistijanto, B.; Muliadi, V.

2018-03-01

Diffie-Hellman (DH) provides an efficient key exchange system by reducing the number of cryptographic keys distributed in the network. In this method, a node broadcasts a single public key to all nodes in the network, and in turn each peer uses this key to establish a shared secret key which then can be utilized to encrypt and decrypt traffic between the peer and the given node. In this paper, we evaluate the key transfer delay and cost performance of DH in opportunistic mobile networks, a specific scenario of MANETs where complete end-to-end paths rarely exist between sources and destinations; consequently, the end-to-end delays in these networks are much greater than typical MANETs. Simulation results, driven by a random node movement model and real human mobility traces, showed that DH outperforms a typical key distribution scheme based on the RSA algorithm in terms of key transfer delay, measured by average key convergence time; however, DH performs as well as the benchmark in terms of key transfer cost, evaluated by total key (copies) forwards.

Energy Management Dynamic Control Topology In MANET

Science.gov (United States)

Madhusudan, G.; Kumar, TNR

2017-08-01

Topology management via per-node transmission power adjustment has been shown effective in extending network lifetime. The existing algorithms constructs static topologies which fail to take the residual energy of network nodes, and cannot balance energy consumption efficiently. To address this problem, a Light Weighted Distributed Topology Control algorithm EMDCT(Energy Management Dynamic Control Topology ) is proposed in this paper. Based on the link metric of the network, both the energy consumption rate level and residual energy levels at the two end nodes are considered. EMDCT generates a Dynamic Topology that changes with the variation of node energy without the aid of location information, each node determines its transmission power according to local network information, which reduces the overhead complexity of EMDCT greatly. The experiment results show that EMDCT preserves network connectivity and manitains minimum-cost property of the network also it can extend network lifetime more remarkably.

A ROBUST CLUSTER HEAD SELECTION BASED ON NEIGHBORHOOD CONTRIBUTION AND AVERAGE MINIMUM POWER FOR MANETs

Directory of Open Access Journals (Sweden)

S.Balaji

2015-06-01

Full Text Available Mobile Adhoc network is an instantaneous wireless network that is dynamic in nature. It supports single hop and multihop communication. In this infrastructure less network, clustering is a significant model to maintain the topology of the network. The clustering process includes different phases like cluster formation, cluster head selection, cluster maintenance. Choosing cluster head is important as the stability of the network depends on well-organized and resourceful cluster head. When the node has increased number of neighbors it can act as a link between the neighbor nodes which in further reduces the number of hops in multihop communication. Promisingly the node with more number of neighbors should also be available with enough energy to provide stability in the network. Hence these aspects demand the focus. In weight based cluster head selection, closeness and average minimum power required is considered for purging the ineligible nodes. The optimal set of nodes selected after purging will compete to become cluster head. The node with maximum weight selected as cluster head. Mathematical formulation is developed to show the proposed method provides optimum result. It is also suggested that weight factor in calculating the node weight should give precise importance to energy and node stability.

Internal strains after recovery of hardness in tempered martensitic steels for fusion reactors

Science.gov (United States)

Brunelli, L.; Gondi, P.; Montanari, R.; Coppola, R.

1991-03-01

After tempering, with recovery of hardness, MANET steels present internal strains; these residual strains increase with quenching rate prior to tempering, and they remain after prolonged tempering times. On account of their persistence, after thermal treatments which lead to low dislocation and sub-boundary densities, the possibility has been considered that the high swelling resistance of MANET is connected with these centres of strain, probably connected with the formation, in ferrite, of Cr-enriched and contiguous Cr-depleted zones which may act as sinks for interstitials. Comparative observations on the internal strain behaviour of cold worked 316L stainless steel appear consistent with this possibility.

Group Centric Networking: A New Approach for Wireless Multi-Hop Networking to Enable the Internet of Things

Science.gov (United States)

2016-01-22

ETX is en- abled. In bandwidth limited environments, this level of background trac may congest the network and not allow data messages to be...no. 7, pp. 1655–1695, 2007. [25] T. Clausen, J. Yi, and A. C. de Verdiere, “Loadng: To- wards aodv version 2,” in Vehicular Technology Confer- ence

Trust Management in Mobile Ad Hoc Networks for Bias Minimization and Application Performance Maximization

Science.gov (United States)

2014-02-26

4 develops a novel model-based approach to de- scribe dynamic behaviors of nodes in MANETs in the pres- ence of misbehaving nodes with the objective...bile node to subjectively yet informatively assess the trust levels of other mobile nodes. Further, SQTrust is resilient against misbehaving nodes. Given...objective trust’’ despite the presence of misbehaving nodes. The desirable output is to achieve high accuracy in peer-to-peer subjective trust evaluation

Analysis of Soldier Radio Waveform Performance in Operational Test

Science.gov (United States)

2015-05-01

different frequencies based on carrier, uplink/downlink, and generation. In general, 2G and 3G cellular phones operate at 850 MHz uplink, and 1,900 MHz...spectrum management that may not be operationally feasible. These issues are not unique to SRW, but rather have plagued the mobile ad-hoc network... mobile ad-hoc network (MANET), enabling communication through a self-configuring, infrastructure-less network of mobile nodes. In the SS domain, these

An Effective Approach for Mobile ad hoc Network via I-Watchdog Protocol

Directory of Open Access Journals (Sweden)

Nidhi Lal

2014-12-01

Full Text Available Mobile ad hoc network (MANET is now days become very famous due to their fixed infrastructure-less quality and dynamic nature. They contain a large number of nodes which are connected and communicated to each other in wireless nature. Mobile ad hoc network is a wireless technology that contains high mobility of nodes and does not depend on the background administrator for central authority, because they do not contain any infrastructure. Nodes of the MANET use radio wave for communication and having limited resources and limited computational power. The Topology of this network is changing very frequently because they are distributed in nature and self-configurable. Due to its wireless nature and lack of any central authority in the background, Mobile ad hoc networks are always vulnerable to some security issues and performance issues. The security imposes a huge impact on the performance of any network. Some of the security issues are black hole attack, flooding, wormhole attack etc. In this paper, we will discuss issues regarding low performance of Watchdog protocol used in the MANET and proposed an improved Watchdog mechanism, which is called by I-Watchdog protocol that overcomes the limitations of Watchdog protocol and gives high performance in terms of throughput, delay.

Implementing a Topology Management Algorithm for Mobile Ad-Hoc Networks

Directory of Open Access Journals (Sweden)

Mrinal K. Naskar

2008-01-01

Full Text Available In this paper, we propose to maintain the topology of a MANET by suitably selecting multiple coordinators among the nodes constituting the MANET. The maintenance of topology in a mobile ad–hoc network is of primary importance because the routing techniques can only work if we have a connected network. Thus of the burning issues at present is to device algorithms which ensure that the network topology is always maintained. The basic philosophy behind our algorithm is to isolate two coordinators amongst the system based on positional data. Once elected, they are entrusted with the responsibility to emit signals of different frequencies while the other nodes individually decide the logic they need to follow in order to maintain the topology, thereby greatly reducing the overhead. As far as our knowledge goes, we are the first ones to introduce the concept of multiple coordinators which not only reduces the workload of the coordinator, but also eliminates the need of different signal ranges thereby ensuring greater efficiency. We have simulated the algorithm with the help of a number of robots using embedded systems. The results we have obtained have been quite encouraging.

An Automated Tool for the Creation of Desired Emulated Topologies of a Mobile Ad-Hoc Network

National Research Council Canada - National Science Library

Nguyen, Binh Q

2006-01-01

This report documents a research effort that the U.S. Army Research Laboratory conducted in FY 2005 in support of the development of advanced technologies for tactical mobile ad hoc networks (MANET...

Energy-Aware Routing Protocol for Ad Hoc Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Mann Raminder P

2005-01-01

Full Text Available Wireless ad hoc sensor networks differ from wireless ad hoc networks from the following perspectives: low energy, lightweight routing protocols, and adaptive communication patterns. This paper proposes an energy-aware routing protocol (EARP suitable for ad hoc wireless sensor networks and presents an analysis for its energy consumption in various phases of route discovery and maintenance. Based on the energy consumption associated with route request processing, EARP advocates the minimization of route requests by allocating dynamic route expiry times. This paper introduces a unique mechanism for estimation of route expiry time based on the probability of route validity, which is a function of time, number of hops, and mobility parameters. In contrast to AODV, EARP reduces the repeated flooding of route requests by maintaining valid routes for longer durations.

Tritium transport in the water cooled Pb-17Li blanket concept of DEMO

International Nuclear Information System (INIS)

Reiter, F.; Tominetti, S.; Perujo, A.

1992-01-01

The code TIRP has been used to calculate the time dependence of tritium inventory and tritium permeation into the coolant and into the first wall boxes in the water cooled Pb-17Li blanket concept of DEMO. The calculations have been performed for the martensitic steel MANET and the austenitic steel AISI 316L as blanket structure materials, for water or helium cooling and for convective or no motion of the liquid breeder in the blanket. Tritium inventories are rather low in blankets with MANET structure and higher in those with AISI 316L structure. Tritium permeation rates are too high in both blankets. Further calculations on tritium inventory and permeation are therefore presented for blankets with TiC permeation barriers of 1 μm thickness on various surfaces of the blanket structure and for blankets with any permeation barriers in function of their thickness, tritium diffusivities, tritium surface recombination rates and atomic densities. These last calculations have been performed for a blanket with coatings on the outer surfaces of the blanket and with a tritium residence time of 10 4 s and for a blanket with coatings on both sides of the cooling tubes and stagnant Pb-17Li in the blanket. The second case for a blanket with MANET structure presents a very interesting solution for tritium recovery by permeation into and pumping from the first wall boxes. (orig.)

Research on Innovating, Applying Multiple Paths Routing Technique Based on Fuzzy Logic and Genetic Algorithm for Routing Messages in Service - Oriented Routing

Directory of Open Access Journals (Sweden)

Nguyen Thanh Long

2015-02-01

Full Text Available MANET (short for Mobile Ad-Hoc Network consists of a set of mobile network nodes, network configuration changes very fast. In content based routing, data is transferred from source node to request nodes is not based on destination addresses. Therefore, it is very flexible and reliable, because source node does not need to know destination nodes. If We can find multiple paths that satisfies bandwidth requirement, split the original message into multiple smaller messages to transmit concurrently on these paths. On destination nodes, combine separated messages into the original message. Hence it can utilize better network resources, causes data transfer rate to be higher, load balancing, failover. Service Oriented Routing is inherited from the model of content based routing (CBR, combined with several advanced techniques such as Multicast, multiple path routing, Genetic algorithm to increase the data rate, and data encryption to ensure information security. Fuzzy logic is a logical field study evaluating the accuracy of the results based on the approximation of the components involved, make decisions based on many factors relative accuracy based on experimental or mathematical proof. This article presents some techniques to support multiple path routing from one network node to a set of nodes with guaranteed quality of service. By using these techniques can decrease the network load, congestion, use network resources efficiently.

Sadhana | Indian Academy of Sciences

Indian Academy of Sciences (India)

Effect of binder type and content on physical and mechanical properties of geopolymers .... Preventing the impact of selfish behavior under MANET using Neighbor .... Investigation of transient conduction–radiation heat transfer in a square ...

Preliminary Analysis of a Trusted Platform Module (TPM) Initialization Process

National Research Council Canada - National Science Library

Wiese, Brian

2007-01-01

.... While work has been done to leverage TPMs for Digital Rights Management (DRM) and other schemes, application of TPMs for robust identification and authentication in a MANET or other distributed environment have not been...

Mobility Tolerant Firework Routing for Improving Reachability in MANETs

Directory of Open Access Journals (Sweden)

Gen Motoyoshi

2014-03-01

Full Text Available In this paper, we investigate our mobility-assisted and adaptive broadcast routing mechanism, called Mobility Tolerant Firework Routing (MTFR, which utilizes the concept of potentials for routing and improves node reachability, especially in situations with high mobility, by including a broadcast mechanism. We perform detailed evaluations by simulations in a mobile environment and demonstrate the advantages of MTFR over conventional potential-based routing. In particular, we show that MTFR produces better reachability in many aspects at the expense of a small additional transmission delay and intermediate traffic overhead, making MTFR a promising routing protocol and feasible for future mobile Internet infrastructures.

The microstructural stability and mechanical properties of two low activation martensitic steels

International Nuclear Information System (INIS)

Victoria, M.; Marmy, P.; Batawi, E.; Peters, J.; Briguet, C.; Rezai-Aria, F.; Gavillet, D.

1996-01-01

A desirable feature of future magnetically confined fusion reactors is the prospect of producing low level radioactive waste. In order to minimize the volume of radioactive material, in particular from the first wall and blanket structures, reduced long term activation alloys are being developed. Here, a low activation composition of a martensitic 9% Cr steel has been studied, based on the DIN (Deutsches Inst. fuer Normung) 1.4914 composition (MANET) but replacing Ni, Mo and Nb by the low activation elements W, V and Ta. Two casts were produced from high purity components, in which the effects of controlled additions of Mn (0.58 and 0.055 wt. %) and N (7 and 290 wt. ppm) were studied, so that the final compositions resulted in one cast with high Mn and low N (steel A) and the other with the opposite conditions (steel B). The two steels were evaluated in terms of structural stability and mechanical properties under tensile, fatigue and fracture toughness tests. It has been found that both alloys have a DBTT below room temperature, which in the case of the steel A is 70 K below that of MANET. Although the tensile strength is somewhat below that of the parent steel, both steels have longer fatigue life

A Family of Key Agreement Mechanisms for Mission Critical Communications for Secure Mobile Ad Hoc and Wireless Mesh Internetworking

Directory of Open Access Journals (Sweden)

Tryfonas Theo

2011-01-01

Full Text Available Future wireless networks like mobile ad hoc networks and wireless mesh networks are expected to play important role in demanding communications such as mission critical communications. MANETs are ideal for emergency cases where the communication infrastructure has been completely destroyed and there is a need for quick set up of communications among the rescue/emergency workers. In such emergency scenarios wireless mesh networks may be employed in a later phase for providing advanced communications and services acting as a backbone network in the affected area. Internetworking of both types of future networks will provide a broad range of mission critical applications. While offering many advantages, such as flexibility, easy of deployment and low cost, MANETs and mesh networks face important security and resilience threats, especially for such demanding applications. We introduce a family of key agreement methods based on weak to strong authentication associated with several multiparty contributory key establishment methods. We examine the attributes of each key establishment method and how each method can be better applied in different scenarios. The proposed protocols support seamlessly both types of networks and consider system and application requirements such as efficient and secure internetworking, dynamicity of network topologies and support of thin clients.

Robust On-Demand Multipath Routing with Dynamic Path Upgrade for Delay-Sensitive Data over Ad Hoc Networks

Directory of Open Access Journals (Sweden)

Sunil Kumar

2013-01-01

Full Text Available Node mobility in mobile ad hoc networks (MANETs causes frequent route breakages and intermittent link stability. In this paper, we introduce a robust routing scheme, known as ad hoc on-demand multipath distance vector with dynamic path update (AOMDV-DPU, for delay-sensitive data transmission over MANET. The proposed scheme improves the AOMDV scheme by incorporating the following features: (i a routing metric based on the combination of minimum hops and received signal strength indicator (RSSI for discovery of reliable routes; (ii a local path update mechanism which strengthens the route, reduces the route breakage frequency, and increases the route longevity; (iii a keep alive mechanism for secondary route maintenance which enables smooth switching between routes and reduces the route discovery frequency; (iv a packet salvaging scheme to improve packet delivery in the event of a route breakage; and (v low HELLO packet overhead. The simulations are carried out in ns-2 for varying node speeds, number of sources, and traffic load conditions. Our AOMDV-DPU scheme achieves significantly higher throughput, lower delay, routing overhead, and route discovery frequency and latency compared to AOMDV. For H.264 compressed video traffic, AOMDV-DPU scheme achieves 3 dB or higher PSNR gain over AOMDV at both low and high node speeds.

A Tool for Visualizing Mobile Ad-Hoc Network Topology Definitions Files

National Research Council Canada - National Science Library

Nguyen, Binh Q

2006-01-01

This report documents a research and development effort that the U.S. Army Research Laboratory conducted in FY05 in support of the building of an emulated tactical mobile ad hoc network (MANET) research test bed...

WOMAN AS OBJECT OF MALE GAZE IN SOME WORKS OF ...

African Journals Online (AJOL)

Nkiruka

marketing and sale of the product, but also an object of male gaze. ... Edward Manet, whose painting Olympia, thought to be inspired by Titian‟s ... encountered in Western art history, whereas unidentifiable nude males were infrequently.

A Survey on Trust Management for Mobile Ad Hoc Networks

Science.gov (United States)

2011-11-01

expects, trust is dangerous implying the possible betrayal of trust. In his comments on Lagerspetz’s book titled Trust: The Tacit Demand, Lahno [24...AODV Zouridaki et al. (2005 ) [79] (2006) [80] Secure routing Direct observation [79][80] Reputation by secondhand information [80] Packet dropping...areas of signal processing, wireless communications, sensor and mobile ad hoc networks. He is co-editor of the book Wireless Sensor Networks: Signal

Research Article Special Issue

African Journals Online (AJOL)

2017-08-08

Aug 8, 2017 ... Due to the specified advantages MANET technology has good application prospects for the development of a ... proposed to carry out on the basis of a hybrid neuro-fuzzy intelligent system that combines .... Artificial neural.

Integrated Social and Quality of Service Trust Management of Mobile Groups in Ad Hoc Networks

Science.gov (United States)

2013-01-01

high resiliency to malicious attacks and misbehaving nodes. Keywords—trust management; mobile ad hoc networks; QoS trust; social trust; trust...paper we address an importance issue of trust management protocol design for MANETs: trust bias minimization despite misbehaving nodes performing

"Scripta" üldpilt on muljetavaldav / Tiina Kolk

Index Scriptorium Estoniae

Kolk, Tiina

2005-01-01

Rahvusvahelisest köitenäitusest "Scripta manet III" Eesti Tarbekunsti- ja Disainimuuseumis. Osaleb 130 kunstnikku 17 riigist. Näitusega kaasneval konkursil pälvisid Kuldraamatu auhinna eesti kunstnikud Külli Grünbach-Sein, Kaire Olt ja Jaana Päeva

Probabilistic Models and Process Calculi for Mobile Ad Hoc Networks

DEFF Research Database (Denmark)

Song, Lei

, thus the network topology may undergo constant changes. Moreover the devices in an MANET are loosely connected not depending on pre-installed infrastructure or central control components, they exchange messages via wireless connections which are less reliable compared to wired connections. Therefore...

Probabilistic monitoring in intrusion detection module for energy efficiency in mobile ad hoc networks

Science.gov (United States)

De Rango, Floriano; Lupia, Andrea

2016-05-01

MANETs allow mobile nodes communicating to each other using the wireless medium. A key aspect of these kind of networks is the security, because their setup is done without an infrastructure, so external nodes could interfere in the communication. Mobile nodes could be compromised, misbehaving during the multi-hop transmission of data, or they could have a selfish behavior to save energy, which is another important constraint in MANETs. The detection of these behaviors need a framework that takes into account the latest interactions among nodes, so malicious or selfish nodes could be detected also if their behavior is changed over time. The monitoring activity increases the energy consumption, so our proposal takes into account this issue reducing the energy required by the monitoring system, keeping the effectiveness of the intrusion detection system. The results show an improvement in the saved energy, improving the detection performance too.

Restricted broadcast process theory

NARCIS (Netherlands)

F. Ghassemi; W.J. Fokkink (Wan); A. Movaghar; A. Cerone; S. Gruner

2008-01-01

htmlabstractWe present a process algebra for modeling and reasoning about Mobile Ad hoc Networks (MANETs) and their protocols. In our algebra we model the essential modeling concepts of ad hoc networks, i.e. local broadcast, connectivity of nodes and connectivity changes. Connectivity and

Cuba en el PIDC

Directory of Open Access Journals (Sweden)

Enrique González Manet

2015-01-01

Full Text Available Intervención de Enrique González Manet, delegado cubano, en la II Reunión del Consejo del Programa Internacional para el Desarrollo de las Comunicaciones -PIDC-en la ciudad de Acapulco, México, el 19 de enero de 1981

Katalog: Malerier, skulpturer, pasteller, tegninger

DEFF Research Database (Denmark)

Anderberg, Birgitte

2011-01-01

Géricault, Eva Gonzalès, Armand Guillaumin, Constantin Guys, Jean-Auguste-Dominique Ingres, Aristide Maillol, Édouard Manet, Albert Marquet, Henri Matisse, Claude Monet, Adolphe Monticelli, Berthe Morisot, Jean-Francois Rafaelli, Odilon Redon, Pierre Auguste Renoir, Auguste Rodin, Théodore Rousseau, Alfred...

The Impact of Packet Loss Behavior in 802.11g on the Cooperation Gain in Reliable Multicast

DEFF Research Database (Denmark)

Heide, Janus; Vingelmann, Peter; Pedersen, Morten Videbæk

2012-01-01

In group-oriented applications for wireless networks, reliable multicast strategies are important in order to efficiently distribute data, e.g. in Wireless Mesh Networks (WMNs) and Mobile Ad-hoc NETworks (MANETs). To ensure that developed protocols and systems will operate as expected when deploy...

Dynamic social community detection and its applications.

Directory of Open Access Journals (Sweden)

Nam P Nguyen

Full Text Available Community structure is one of the most commonly observed features of Online Social Networks (OSNs in reality. The knowledge of this feature is of great advantage: it not only provides helpful insights into developing more efficient social-aware solutions but also promises a wide range of applications enabled by social and mobile networking, such as routing strategies in Mobile Ad Hoc Networks (MANETs and worm containment in OSNs. Unfortunately, understanding this structure is very challenging, especially in dynamic social networks where social interactions are evolving rapidly. Our work focuses on the following questions: How can we efficiently identify communities in dynamic social networks? How can we adaptively update the network community structure based on its history instead of recomputing from scratch? To this end, we present Quick Community Adaptation (QCA, an adaptive modularity-based framework for not only discovering but also tracing the evolution of network communities in dynamic OSNs. QCA is very fast and efficient in the sense that it adaptively updates and discovers the new community structure based on its history together with the network changes only. This flexible approach makes QCA an ideal framework applicable for analyzing large-scale dynamic social networks due to its lightweight computing-resource requirement. To illustrate the effectiveness of our framework, we extensively test QCA on both synthesized and real-world social networks including Enron, arXiv e-print citation, and Facebook networks. Finally, we demonstrate the applicability of QCA in real applications: (1 A social-aware message forwarding strategy in MANETs, and (2 worm propagation containment in OSNs. Competitive results in comparison with other methods reveal that social-based techniques employing QCA as a community detection core outperform current available methods.

Dynamic social community detection and its applications.

Science.gov (United States)

Nguyen, Nam P; Dinh, Thang N; Shen, Yilin; Thai, My T

2014-01-01

Community structure is one of the most commonly observed features of Online Social Networks (OSNs) in reality. The knowledge of this feature is of great advantage: it not only provides helpful insights into developing more efficient social-aware solutions but also promises a wide range of applications enabled by social and mobile networking, such as routing strategies in Mobile Ad Hoc Networks (MANETs) and worm containment in OSNs. Unfortunately, understanding this structure is very challenging, especially in dynamic social networks where social interactions are evolving rapidly. Our work focuses on the following questions: How can we efficiently identify communities in dynamic social networks? How can we adaptively update the network community structure based on its history instead of recomputing from scratch? To this end, we present Quick Community Adaptation (QCA), an adaptive modularity-based framework for not only discovering but also tracing the evolution of network communities in dynamic OSNs. QCA is very fast and efficient in the sense that it adaptively updates and discovers the new community structure based on its history together with the network changes only. This flexible approach makes QCA an ideal framework applicable for analyzing large-scale dynamic social networks due to its lightweight computing-resource requirement. To illustrate the effectiveness of our framework, we extensively test QCA on both synthesized and real-world social networks including Enron, arXiv e-print citation, and Facebook networks. Finally, we demonstrate the applicability of QCA in real applications: (1) A social-aware message forwarding strategy in MANETs, and (2) worm propagation containment in OSNs. Competitive results in comparison with other methods reveal that social-based techniques employing QCA as a community detection core outperform current available methods.

Cross-Layer Design Approach for Power Control in Mobile Ad Hoc Networks

Directory of Open Access Journals (Sweden)

A. Sarfaraz Ahmed

2015-03-01

Full Text Available In mobile ad hoc networks, communication among mobile nodes occurs through wireless medium The design of ad hoc network protocol, generally based on a traditional “layered approach”, has been found ineffective to deal with receiving signal strength (RSS-related problems, affecting the physical layer, the network layer and transport layer. This paper proposes a design approach, deviating from the traditional network design, toward enhancing the cross-layer interaction among different layers, namely physical, MAC and network. The Cross-Layer design approach for Power control (CLPC would help to enhance the transmission power by averaging the RSS values and to find an effective route between the source and the destination. This cross-layer design approach was tested by simulation (NS2 simulator and its performance over AODV was found to be better.

Context discovery in ad-hoc networks

NARCIS (Netherlands)

Liu, F.

2011-01-01

With the rapid development of wireless technology and portable devices, mobile ad-hoc networks (MANETs) are more and more present in our daily life. Ad-hoc networks are often composed of mobile and battery-supplied devices, like laptops, mobile phones, and PDAs. With no requirement for

Mehed ruumis / Rosalyn Deutsche

Index Scriptorium Estoniae

Deutsche, Rosalyn

2004-01-01

1985. a. ilmunud T. J. Clarki raamatust "Modernse elu maalikunst: Pariis Manet' ja tema järgijate kunstis". 1989. a. ilmunud Edward W. Soja raamatust "Postmodernistlikud geograafiad" ja David Harvey raamatust "Postmodernne olukord". 1984. a. avaldatud Fredric Jamesoni artiklist "Postmodernism ehk hiliskapitalismi kultuuriline loogika". Bibliograafia lk. 81

Nuclear fusion project. Semi-annual report of the Association KfK/Euratom

International Nuclear Information System (INIS)

Kast, G.

1989-11-01

Report on the technology program for NET: Plasma facing components, magnets, tritium fuel cycle, basic blanket, remote handling and maintenance, safety and environment, solid breeder and liquid metal test blankets, mechanical properties of pre- and post-irradiation of 1.4914 steel (MANET), ECRH power sources, NET study contracts. (HP)

Nuclear fusion project. Annual report of the Association KfK/EURATOM

International Nuclear Information System (INIS)

Kast, G.

1990-09-01

Report on the technology program for NET: Plasma facing components, magnets, tritium fuel cycle, basic blanket, remote handling and maintenance, safety and environment, solid breeder and liquid metal test blankets, mechanical properties of pre- and post-irradiation of 1.4914 steel (MANET). ECRH power sources, NET study contracts. (HP)

Nuclear Fusion Project. Annual report of the Association KfK/EURATOM

International Nuclear Information System (INIS)

Kast, G.

1991-10-01

Report on the technology program for NET: Plasma facing components magnets, tritium fuel cycle, basic blanket, remote handling and maintenance, safety and environment, solid breeder and liquid metal test blankets, mechanical properties of pre- and post-irradiation of 1.4914 steel (MANET). ECRH power sources, NET study contracts. (orig.)

Secrecy in Mobile Ad-hoc Networks

DEFF Research Database (Denmark)

Hüttel, Hans; Rafnsson, Willard

2008-01-01

We propose a framework for automated verification of secrecy properties of MANET protocols, consisting of a formal language and a proven sound verifi- cation technique which can be automated. We start off by presenting the dis- tributed applied pi calculus with broadcast (DAπβ ), whereafter we summ...

Teekond pildi sisse / Liina Jänes

Index Scriptorium Estoniae

Jänes, Liina, 1977-

2008-01-01

Tutvustatakse kümmet tundeküllast maali: Caravaggio "Lautomängija", Rembrandt "Autoportree Saskiaga", Fragonard "Kiik", Goya "Alasti maja", Manet "Eine murul", Corot "Orfeus juhib Euridiket läbi allilma", Ingres "Türgi saun", Vrubel "Istuv deemon", Magritte "Magamistoa filosoofia", Jack Vettriano "Hüvastijätutants armsamaga"

UMDR: Multi-Path Routing Protocol for Underwater Ad Hoc Networks with Directional Antenna

Science.gov (United States)

Yang, Jianmin; Liu, Songzuo; Liu, Qipei; Qiao, Gang

2018-01-01

This paper presents a new routing scheme for underwater ad hoc networks based on directional antennas. Ad hoc networks with directional antennas have become a hot research topic because of space reuse may increase networks capacity. At present, researchers have applied traditional self-organizing routing protocols (such as DSR, AODV) [1] [2] on this type of networks, and the routing scheme is based on the shortest path metric. However, such routing schemes often suffer from long transmission delays and frequent link fragmentation along the intermediate nodes of the selected route. This is caused by a unique feature of directional transmission, often called as “deafness”. In this paper, we take a different approach to explore the advantages of space reuse through multipath routing. This paper introduces the validity of the conventional routing scheme in underwater ad hoc networks with directional antennas, and presents a special design of multipath routing algorithm for directional transmission. The experimental results show a significant performance improvement in throughput and latency.

The Role of Electronic Learning Technology in Networks Systems

International Nuclear Information System (INIS)

Abd ELhamid, A.; Ayad, N.M.A.; Fouad, Y.; Abdelkader, T.

2016-01-01

Recently, Electronic Learning Technology (ELT) has been widely spread as one of the new technologies in the world through using Information and Communication Technology (ICT). One of the strategies of ELT is Simulation, for instance Military and Medical simulations that are used to avoid risks and reduce Costs. A wireless communication network refers to any network not physically connected by cables, which enables the desired convenience and mobility for the user. Wireless communication networks have been useful in areas such as commerce, education and defense. According to the nature of a particular application, they can be used in home-based and industrial systems or in commercial and military environments. Historically, Mobile Ad-hoc Networks (MANET) have primarily been used for tactical military network related applications to improve battlefield communications/ survivability. MANET is a collection of wireless nodes that can dynamically be set up anywhere and anytime without using any pre-existing network infrastructure. Mobility in wireless networks basically refers to nodes changing its point of attachment to the network. Also, how the end terminals can move, there are many mobility models described the movement of nodes, many researchers use the Random Way point Mobility Model (RWPM). In this paper, a Graphical User Interface (GUI) for RWPM simulation is introduced as a proposal to be used through ELT Project. In the research area of computer and communications networks, simulation is a very useful technique for the behavior of networks

Author Details

African Journals Online (AJOL)

Folaponmile, A. Vol 8, No 2 (2010) - Articles Interference mitigation techniques in wireless communications systems. Abstract · Vol 9, No 2 (2011) - Articles Implementation of a Fuzzy Logic Speed Controller for a Permanent Magnet Brushless DC Motor Drive System Abstract · Vol 9, No 2 (2011) - Articles Manet: A reliable ...

Secure Infrastructure-Less Network (SINET)

Science.gov (United States)

2017-06-01

WIRELESS TECHNOLOGY IN MOBILE DEVICES ..................................................................................................18 1. 4G LTE ...System LOS Line of Sight LTE Long-Term Evolution MANET Mobile Ad-hoc Network MCP Mobility Capabilities Package MPR Multipoint Relays NFC...National Security Agency, 2003). CCI, while unclassified, still requires strict physical control measures to protect against loss or compromise

Modelling Mobility in Mobile AD-HOC Network Environments ...

African Journals Online (AJOL)

In the simulation of mobile ad-hoc networks (MANETs), the probability distribution governing the movement of nodes typically varies over time and converges to a steady state distribution, known as the stationary distribution. This paper presents and evaluates the stationary distribution for location, speed and pause time of a ...

An Improvement over PBOA MAC Protocol by Considering Link Quality in MANET

OpenAIRE

Shariati, Nafiseh; Shirazinia, Amirpasha

2008-01-01

We propose a methodology for improving theperformance of Progressive Back Off Algorithm (PBOA)which is a protocol that performs medium access controljointly with power control in Ad-hoc networks.Our method selects the optimum SNR thresholds based onlink quality. It adjusts the role of nodes’ mobility in network throughput. Simulation results show that the improvedprotocol outperforms PBOA without adaptation taken from link quality. Qc 20120131

Testing Applications in MANET Environments through Emulation

Directory of Open Access Journals (Sweden)

Pietro Manzoni

2009-01-01

Full Text Available Mobile Ad Hoc Network solution testing is typically done using simulation. The simulated code is generally a simplified version of the real code, and thus code porting to actual operating systems lacks a strong validation. In this work we present Castadiva, a test-bed architecture that allows validating software solutions for real ad hoc network environments using low-cost, off-the-shelf devices and open source software. Castadiva is also compatible with the ns-2 simulator, allowing a combined and more complete evaluation. In this work we present our tool and the results obtained when evaluating videocalls in different scenarios, both static and dynamic.

Survey on Reputation and Trust in MANETS

OpenAIRE

A. S. Gowri

2014-01-01

Wireless Self organizing networks rely[1] on node cooperation to perform and support basic functions like packet forwarding, routing and network management . Lack of Infrastructure, resource constraints and organizational environment of self organizing nodes make them vulnerable to newer threats and challenges. By default, [2] non- cooperative misbehavior activities of the nodes will slowly lead to the performance deterioration of the network. Hence the responsibility of ensuring security and...

A microstructural comparison of two nuclear-grade martensitic steels using small-angle neutron scattering

Science.gov (United States)

Coppola, R.; Fiori, F.; Little, E. A.; Magnani, M.

1997-06-01

Results are presented of a small-angle neutron scattering (SANS) study on two 10-13% Cr martensitic stainless steels of interest for nuclear applications, viz. DIN 1.4914 (MANET specification, for fusion reactors) and AISI 410. The investigation has focussed principally on microstructural effects associated with the differences in chromium content between the two alloys. The size distribution functions determined from nuclear and magnetic SANS components for the two steels given identical heat treatments are in accord with an interpretation based on the presence of ˜ 1 nm size CCr aggregates in the microstructure. Much larger (˜ 10 nm) scattering inhomogeneities with different magnetic contrast are also present and tentatively identified as carbides.

Minimizing Broadcast Expenses in Clustered Ad-hoc Networks

Directory of Open Access Journals (Sweden)

S. Zeeshan Hussain

2018-01-01

Full Text Available One way to minimize the broadcast expenses of routing protocols is to cluster the network. In clustered ad-hoc networks, all resources can be managed easily by resolving scalability issues. However, blind query broadcast is a major issue that leads to the broadcast storm problem in clustered ad-hoc networks. This query broadcast is done to carry out the route-search task that leads to the unnecessary propagation of route-query even after route has been found. Hence, this query propagation poses the problem of congestion in the network. In particular this motivates us to propose a query-control technique in such networks which works based on broadcast repealing. A huge amount of work has been devoted to propose the query control broadcasting techniques. However, such techniques used in traditional broadcasting mechanisms need to be properly extended for use in the cluster based routing architecture. In this paper, query-control technique is proposed for cluster based routing technique to reduce the broadcast expenses. Finally, we report some experiments which compare the proposed technique to other commonly used techniques including standard one-class AODV that follows TTL-sequence based broadcasting technique.

pyGFC - A Python Extension to the C++ Geodesy Foundation Classes

Science.gov (United States)

2008-09-01

imperative for a successful emulation of a dynamic MANET as intended. To achieve this objective, the same algorithm and its implementation for...solution has two options: (1) selecting, implementing, and integrating an appropriate algorithm into the tool and in the MANE system, or (2) using an...GFCCoord *estimate_southeast_coords(double, double); double lat; double lon; double alt; private: CEarth *earth; char * cstr

Where-Fi: a dynamic energy-efficient multimedia distribution framework for MANETs

Science.gov (United States)

Mohapatra, Shivajit; Carbunar, Bogdan; Pearce, Michael; Chaudhri, Rohit; Vasudevan, Venu

2008-01-01

Next generation mobile ad-hoc applications will revolve around users' need for sharing content/presence information with co-located devices. However, keeping such information fresh requires frequent meta-data exchanges, which could result in significant energy overheads. To address this issue, we propose distributed algorithms for energy efficient dissemination of presence and content usage information between nodes in mobile ad-hoc networks. First, we introduce a content dissemination protocol (called CPMP) for effectively distributing frequent small meta-data updates between co-located devices using multicast. We then develop two distributed algorithms that use the CPMP protocol to achieve "phase locked" wake up cycles for all the participating nodes in the network. The first algorithm is designed for fully-connected networks and then extended in the second to handle hidden terminals. The "phase locked" schedules are then exploited to adaptively transition the network interface to a deep sleep state for energy savings. We have implemented a prototype system (called "Where-Fi") on several Motorola Linux-based cell phone models. Our experimental results show that for all network topologies our algorithms were able to achieve "phase locking" between nodes even in the presence of hidden terminals. Moreover, we achieved battery lifetime extensions of as much as 28% for fully connected networks and about 20% for partially connected networks.

DMP: Detouring Using Multiple Paths against Jamming Attack for Ubiquitous Networking System

Directory of Open Access Journals (Sweden)

Mihui Kim

2010-04-01

Full Text Available To successfully realize the ubiquitous network environment including home automation or industrial control systems, it is important to be able to resist a jamming attack. This has recently been considered as an extremely threatening attack because it can collapse the entire network, despite the existence of basic security protocols such as encryption and authentication. In this paper, we present a method of jamming attack tolerant routing using multiple paths based on zones. The proposed scheme divides the network into zones, and manages the candidate forward nodes of neighbor zones. After detecting an attack, detour nodes decide zones for rerouting, and detour packets destined for victim nodes through forward nodes in the decided zones. Simulation results show that our scheme increases the PDR (Packet Delivery Ratio and decreases the delay significantly in comparison with rerouting by a general routing protocol on sensor networks, AODV (Ad hoc On Demand Distance Vector, and a conventional JAM (Jammed Area Mapping service with one reroute.

DMP: detouring using multiple paths against jamming attack for ubiquitous networking system.

Science.gov (United States)

Kim, Mihui; Chae, Kijoon

2010-01-01

To successfully realize the ubiquitous network environment including home automation or industrial control systems, it is important to be able to resist a jamming attack. This has recently been considered as an extremely threatening attack because it can collapse the entire network, despite the existence of basic security protocols such as encryption and authentication. In this paper, we present a method of jamming attack tolerant routing using multiple paths based on zones. The proposed scheme divides the network into zones, and manages the candidate forward nodes of neighbor zones. After detecting an attack, detour nodes decide zones for rerouting, and detour packets destined for victim nodes through forward nodes in the decided zones. Simulation results show that our scheme increases the PDR (Packet Delivery Ratio) and decreases the delay significantly in comparison with rerouting by a general routing protocol on sensor networks, AODV (Ad hoc On Demand Distance Vector), and a conventional JAM (Jammed Area Mapping) service with one reroute.

Status of EC solid breeder blanket designs and R and D for demo fusion reactors

International Nuclear Information System (INIS)

Proust, E.; Anzidei, L.; Moons, F.

1994-01-01

Within the European Community Fusion Technology Program two solid breeder blankets for a DEMO reactor are being developed. The two blankets have various features in common: helium as coolant and as tritium purge gas, the martensitic steel MANET as structural material and beryllium as neutron multiplier. The configurations of the two blankets are however different: in the B.I.T. (Breeder Inside Tube) concept the breeder materials are LiAlO 2 or Li 2 ZrO 3 in the form of annular pellets contained in tubes surrounded by beryllium blocks, the coolant helium being outside the tubes, whereas in the B.O.T. (Breeder out of Tube) the breeder and multiplier material are Li 4 SiO 4 and beryllium pebbles forming a mixed bed placed outside the tubes containing the coolant helium. The main critical issues for both blankets are the behavior of the breeder ceramics and of beryllium under irradiation and the tritium control. Other issues are the low temperature irradiation induced embrittlement of MANET, the mechanical effects caused by major plasma disruptions, and safety and reliability. The R and D work concentrate on these issues. The development of martensitic steels including MANET is part of a separate program. Breeder ceramics and beryllium irradiations have been so far performed for conditions which do not cover the peak values injected in the DEMO blankets. Further irradiations in thermal reactors and in fast reactors, especially for beryllium, are required. An effective tritium control requires the development of permeation barriers and/or of methods of oxidation of the tritium in the main helium cooling systems. First promising results have been obtained also in field of mechanical effects from plasma disruptions and safety and reliability, however further work is required in the reliability field and to validate the codes for the calculations of the plasma disruption effects. (authors). 8 figs., 2 tabs., 53 refs

Intelligent routing protocol for ad hoc wireless network

Science.gov (United States)

Peng, Chaorong; Chen, Chang Wen

2006-05-01

A novel routing scheme for mobile ad hoc networks (MANETs), which combines hybrid and multi-inter-routing path properties with a distributed topology discovery route mechanism using control agents is proposed in this paper. In recent years, a variety of hybrid routing protocols for Mobile Ad hoc wireless networks (MANETs) have been developed. Which is proactively maintains routing information for a local neighborhood, while reactively acquiring routes to destinations beyond the global. The hybrid protocol reduces routing discovery latency and the end-to-end delay by providing high connectivity without requiring much of the scarce network capacity. On the other side the hybrid routing protocols in MANETs likes Zone Routing Protocol still need route "re-discover" time when a route between zones link break. Sine the topology update information needs to be broadcast routing request on local zone. Due to this delay, the routing protocol may not be applicable for real-time data and multimedia communication. We utilize the advantages of a clustering organization and multi-routing path in routing protocol to achieve several goals at the same time. Firstly, IRP efficiently saves network bandwidth and reduces route reconstruction time when a routing path fails. The IRP protocol does not require global periodic routing advertisements, local control agents will automatically monitor and repair broke links. Secondly, it efficiently reduces congestion and traffic "bottlenecks" for ClusterHeads in clustering network. Thirdly, it reduces significant overheads associated with maintaining clusters. Fourthly, it improves clusters stability due to dynamic topology changing frequently. In this paper, we present the Intelligent Routing Protocol. First, we discuss the problem of routing in ad hoc networks and the motivation of IRP. We describe the hierarchical architecture of IRP. We describe the routing process and illustrate it with an example. Further, we describe the control manage

AUTHENTICATION ARCHITECTURE USING THRESHOLD CRYPTOGRAPHY IN KERBEROS FOR MOBILE AD HOC NETWORKS

Directory of Open Access Journals (Sweden)

Hadj Gharib

2014-06-01

Full Text Available The use of wireless technologies is gradually increasing and risks related to the use of these technologies are considerable. Due to their dynamically changing topology and open environment without a centralized policy control of a traditional network, a mobile ad hoc network (MANET is vulnerable to the presence of malicious nodes and attacks. The ideal solution to overcome a myriad of security concerns in MANET’s is the use of reliable authentication architecture. In this paper we propose a new key management scheme based on threshold cryptography in kerberos for MANET’s, the proposed scheme uses the elliptic curve cryptography method that consumes fewer resources well adapted to the wireless environment. Our approach shows a strength and effectiveness against attacks.

Explicit Context Matching in Content-Based Publish/Subscribe Systems

Directory of Open Access Journals (Sweden)

Miguel Jiménez

2013-03-01

Full Text Available Although context could be exploited to improve performance, elasticity and adaptation in most distributed systems that adopt the publish/subscribe (P/S communication model, only a few researchers have focused on the area of context-aware matching in P/S systems and have explored its implications in domains with highly dynamic context like wireless sensor networks (WSNs and IoT-enabled applications. Most adopted P/S models are context agnostic or do not differentiate context from the other application data. In this article, we present a novel context-aware P/S model. SilboPS manages context explicitly, focusing on the minimization of network overhead in domains with recurrent context changes related, for example, to mobile ad hoc networks (MANETs. Our approach represents a solution that helps to effciently share and use sensor data coming from ubiquitous WSNs across a plethora of applications intent on using these data to build context awareness. Specifically, we empirically demonstrate that decoupling a subscription from the changing context in which it is produced and leveraging contextual scoping in the filtering process notably reduces (unsubscription cost per node, while improving the global performance/throughput of the network of brokers without altering the cost of SIENA-like topology changes.

Fault-tolerance of Cluster Management in (MANETs) by assistant and mobile agents

International Nuclear Information System (INIS)

Hamad, H.

2007-01-01

Most researches today trend to clustering in ad hoc networks as a solution to the management problem in flat ad hoc networks. Clustering aims to choose suitable nodes to lead the network i.e., the cluster heads. When a cluster head fails, reclustering is needed. However, this will be costly due to the characteristics of the ad hoc networks such as mobility and exhaustion. In this research we developed a fault tolerance mechanism to avoid re-clustering and other drawbacks that result from loosing the Cluster Head (CH). A Mobile Agent (MA) will be responsible of carrying out the jobs of the CH i.e., the CH will host the MA which will be the real manager of the cluster. Furthermore, the closest node to the CH will be chosen as an assistant and the MA will update the assistant. Each of the CH and the assistant will have Remote Objects (RO) to communicate with each other. The main jobs of the assistant are to temporarily replace the CH when fails; then it will choose the next CH based on clustering algorithm. Simulation results show an enhancement of the performance of using an assistant, MA and RO. (author)

Intrusion detection in Mobile Ad-hoc Networks: Bayesian game formulation

Directory of Open Access Journals (Sweden)

Basant Subba

2016-06-01

Full Text Available Present Intrusion Detection Systems (IDSs for MANETs require continuous monitoring which leads to rapid depletion of a node's battery life. To address this issue, we propose a new IDS scheme comprising a novel cluster leader election process and a hybrid IDS. The cluster leader election process uses the Vickrey–Clarke–Groves mechanism to elect the cluster leader which provides the intrusion detection service. The hybrid IDS comprises a threshold based lightweight module and a powerful anomaly based heavyweight module. Initially, only the lightweight module is activated. The decision to activate the heavyweight module is taken by modeling the intrusion detection process as an incomplete information non-cooperative game between the elected leader node and the potential malicious node. Simulation results show that the proposed scheme significantly reduces the IDS traffic and overall power consumption in addition to maintaining a high detection rate and accuracy.

Improving the Dominating-Set Routing over Delay-Tolerant Mobile Ad-Hoc Networks via Estimating Node Intermeeting Times

Directory of Open Access Journals (Sweden)

Preiss Bruno

2011-01-01

Full Text Available With limited coverage of wireless networks and frequent roaming of mobile users, providing a seamless communication service poses a technical challenge. In our previous research, we presented a supernode system architecture that employs the delay-tolerant network (DTN concept to provide seamless communications for roaming users over interconnected heterogeneous wireless networks. Mobile ad hoc networks (MANETs are considered a key component of the supernode system for services over an area not covered by other wireless networks. Within the super node system, a dominating-set routing technique is proposed to improve message delivery over MANETs and to achieve better resource utilization. The performance of the dominating-set routing technique depends on estimation accuracy of the probability of a future contact between nodes. This paper studies how node mobility can be modeled and used to better estimate the probability of a contact. We derive a distribution for the node-to-node intermeeting time and present numerical results to demonstrate that the distribution can be used to improve the dominating-set routing technique performance. Moreover, we investigate how the distribution can be employed to relax the constraints of selecting the dominating-set members in order to improve the system resource utilization.

Supervision de la sécurité pour des réseaux ad hoc mobiles : un système léger, robuste, et fiable de détection d'intrusion

OpenAIRE

Alattar , Mouhannad

2013-01-01

Mobile Ad hoc NETworks (referred to as MANETs) continue increasing their presence in our every day life. They become a corner stone in the commercial, the society, the military, the science, and even the next-generation applications. However, these networks mostly operate over open environments and are therefore vulnerable to a large body of threats. Traditional ways of securing networks relying on preventive techniques, e.g., firewall and encryption, are not sufficient and should henceforth ...

Hydrogen isotopes transport parameters in fusion reactor materials

International Nuclear Information System (INIS)

Serra, E.; Ogorodnikova, O.V.

1998-01-01

This work presents a review of hydrogen isotopes-materials interactions in various materials of interest for fusion reactors. The relevant parameters cover mainly diffusivity, solubility, trap concentration and energy difference between trap and solution sites. The list of materials includes the martensitic steels (MANET, Batman and F82H-mod.), beryllium, aluminium, beryllium oxide, aluminium oxide, copper, tungsten and molybdenum. Some experimental work on the parameters that describe the surface effects is also mentioned. (orig.)

Use Cases for Dynamic Secure Wireless Networking in Coalition Environments (Cas d utilisation de r seau sans fil dynamique et s curis dans des environnements de coalition)

Science.gov (United States)

2015-05-01

Provider Willingness 15 and Degree of Exposure STO-TR-IST-109 v vi STO-TR-IST-109 List of Acronyms CC Coloured Cloud CoI Community of...could be applied to the MANET connectivity scenario. In PCN terminology [4]2, an E-node3 advertises guarantees of bandwidth and other services of...its Coloured Cloud4 (CC). It will be equipped with Service-Level Agreement (SLA) management functions, including support for security and risk. In

User-centred and context-aware identity management in mobile ad-hoc networks

CERN Document Server

Arabo, Abdullahi

2013-01-01

The emergent notion of ubiquitous computing makes it possible for mobile devices to communicate and provide services via networks connected in an ad-hoc manner. These have resulted in the proliferation of wireless technologies such as Mobile Ad-hoc Networks (MANets), which offer attractive solutions for services that need flexible setup as well as dynamic and low cost wireless connectivity. However, the growing trend outlined above also raises serious concerns over Identity Management (IM) du...

A Novel Architecture for Intrusion Detection in Mobile Ad hoc Network

OpenAIRE

Atul Patel; Ruchi Kansara; Dr. Paresh Virparia

2011-01-01

Today’s wireless networks are vulnerable in many ways including illegal use, unauthorized access, denial of service attacks, eavesdropping so called war chalking. These problems are one of the main issues for wider uses of wireless network. On wired network intruder can access by wire but in wireless it has possibilities to access the computer anywhere in neighborhood. However, securing MANETs is highly challenging issue due to their inherent characteristics. Intrusion detection is an importa...

Nuclear fusion project. Annual report of the Association KfK/EURATOM. October 1992 - September 1993

International Nuclear Information System (INIS)

Kast, G.

1993-12-01

The central areas of work are: 1) Structural materials, plasma forming components, plasma engineering; 2) superconducting magnets; 3) vacuum systems; 4) basic blanket; 5) remote handling and maintenance; 6) safety and environment; 7) material development, mechanical properties of pre- and post-irradiation of MANET (steel 1.4914); 8) solid breeder and liquid metal test blankets; 9) ECRH power sources; 10) TRT-1=tritium supply and management; 11) study contracts for ITER/NET. (HP)

Effects of Data Replication on Data Exfiltration in Mobile Ad Hoc Networks Utilizing Reactive Protocols

Science.gov (United States)

2015-03-01

aerial vehicle VANET vehicular ad hoc network VoIP Voice over Internet Protocol VRR Virtual Ring Routing xiii EFFECTS OF DATA REPLICATION ON DATA...ad hoc networks in mobile ad hoc networks (MANETs), vehicular ad hoc networks (VANETs), and flying ad hoc net- works (FANETs). Much of the research...metric, such as capacity, congestion , power, or combinations thereof. Caro refers to two different types of ants, FANTs and BANTs which are analogous to

Cognitive Radio Networks for Tactical Wireless Communications

Science.gov (United States)

2014-12-01

exists. Instead, security is an evolving process, as we have seen in the context of WLANs and 2G / 3G networks. New system vulnerabilities continue to...in the network configuration and radio parameters take place due to mobility of platforms, and variation in other users of the RF environment. CRNs...dynamic spectrum access experimentally, and it represents the largest military Mobile Ad hoc Network (MANET) as of today. The WNaN demonstrator has been

A Bioinspired Adaptive Congestion-Avoidance Routing for Mobile Ad Hoc Networks

Directory of Open Access Journals (Sweden)

Huang Qiong

2014-01-01

Full Text Available Traditional mobile Ad Hoc network routing protocols are mainly based on the Shortest Path, which possibly results in many congestion nodes that incur routing instability and rerouting. To mitigate the side-efforts, this paper proposed a new bioinspired adaptive routing protocol (ATAR based on a mathematics biology model ARAS. This paper improved the ARAS by reducing the randomness and by introducing a new routing-decision metric “the next-hop fitness” which was denoted as the congestion level of node and the length of routing path. In the route maintenance, the nodes decide to forward the data to next node according to a threshold value of the fitness. In the recovery phase, the node will adopt random manner to select the neighbor as the next hop by calculation of the improved ARAS. With this route mechanism, the ATAR could adaptively circumvent the congestion nodes and the rerouting action is taken in advance. Theoretical analysis and numerical simulation results show that the ATAR protocol outperforms AODV and MARAS in terms of delivery ratio, ETE delay, and the complexity. In particular, ATAR can efficiently mitigate the congestion.

Analysis of CBRP for UDP and TCP Traffic-Classes to measure throughput in MANETs

Directory of Open Access Journals (Sweden)

Hardeep Singh Rayait

2013-01-01

Full Text Available In this paper, we analyse the throughput of both TCP and UDP traffic classes for cluster based routing protocol for mobile ad hoc network. It uses clustering structure to improve throughput , decrease average end-to-end delay and improve the average packet delivery ratio. We simulate our routing protocol for nodes running the IEEE802.11 MAC for analysis of throughput for both UDP and TCP traffic classes. The application layer protocol used for UDP is CBR and for TCP is FTP.

Evaluation of VoIP QoS Performance in Wireless Mesh Networks

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Mohammad Tariq Meeran

2017-07-01

Full Text Available The main focus of this research article is the evaluation of selected voice over Internet protocol (VoIP solutions in wireless mesh network (WMN scenarios. While WMNs have self-healing, self-forming, and dynamic topology features, they still pose challenges for the implementation of multimedia applications such as voice in various scenarios. Therefore, various solutions to make WMN more suitable for VoIP application have been proposed in the scientific literature. In this work, we have extensively explored a set of applicable scenarios by conducting experiments by means of a network simulator. The following scenarios were selected as the most representatives for performance evaluation: first responders, flooded village, remote village, and platoon deployment. Each selected scenario has been studied under six sub-scenarios corresponding to various combinations of the IEEE 802.11g, 802.11n, 802.11s, and 802.11e standards; the G.711 and G.729 codecs; and the ad hoc on demand distance vector (AODV and hybrid wireless mesh protocol (HWMP routing protocols. The results in terms of quality of service (measured with the mean opinion score rating scale, supported by the analysis of delay, jitter and packet loss, show that 802.11g integration with both VoIP codecs and AODV routing protocol results in better VoIP performance as compared to most other scenarios. In case of 802.11g integration with 802.11s, VoIP performance decreases as compared to the other sub-scenarios without 802.11s. The results also show that 802.11n integration with 802.11e decreases VoIP performance in larger deployments. We conclude the paper with some recommendations in terms of combinations of those standards and protocols with a view to achieve a higher quality of service for the given scenarios.

Studi Komparatif Lukisan Perempuan Perupa dengan Pria Perupa Impresionis dalam Tema Kehidupan Keseharian

OpenAIRE

Ira Adriati Winarno; Agus Sachari

2008-01-01

Impressionism is an art movement that firstly established in France in the middle of 19th century. Claude Monet, Èdouard Manet, Pierre-Auguste Renoir, and Edgar Degas are famous male impressionist artists that were known by many, yet there are famous female impressionist artists such as Berthe Morisot, Mary Cassatt, Eva Gonzales, and Marie Bracquemond that deserve to be known as well. The presented paper discusses the aesthetics value and meanings of paintings of these female impressionist ar...

US Army Research Laboratory and University of Notre Dame Distributed Sensing: Software Overview

Science.gov (United States)

2017-09-01

Raspberry Pi) limited the usable bandwidth to 2 MHz. A commercial mobile ad-hoc network (MANET) was set up among the central host and the remote...graphical interface that is used to design and generate GR modules. It translates a graphically designed flowchart to a Python script that can...communicate with SDRs. The script it generates uses commands linked to GR blocks that are written in C++ for speed and efficiency. The software runs in the

Analysis of DDoS Attack Effect and Protection Scheme in Wireless Mobile Ad-hoc Network

OpenAIRE

Ramratan Ahirwal; Leeladhar Mahour

2012-01-01

In Wireless mobile Ad Hoc Networks (MANET) every node functions as transmitter, router and data sink is network without infrastructure. Detecting malicious nodes in an open ad-hoc network in whichparticipating nodes have no previous security associations presents a number of challenges not faced by traditional wired networks. Traffic monitoring in wired networks is usually performed at switches,routers and gateways, but an ad-hoc network does not have these types of network elements where the...

Analysis of interference performance of tactical radio network

Science.gov (United States)

Nie, Hao; Cai, Xiaoxia; Chen, Hong

2017-08-01

Mobile Ad hoc network has a strong military background for its development as the core technology of the backbone network of US tactical Internet. And which tactical radio network, is the war in today's tactical use of the Internet more mature form of networking, mainly used in brigade and brigade following forces. This paper analyzes the typical protocol AODV in the tactical radio network, and then carries on the networking. By adding the interference device to the whole network, the battlefield environment is simulated, and then the throughput, delay and packet loss rate are analyzed, and the performance of the whole network and the single node before and after the interference is obtained.

An efficient algorithm for the detection of exposed and hidden wormhole attack

International Nuclear Information System (INIS)

Khan, Z.A.; Rehman, S.U.; Islam, M.H.

2016-01-01

MANETs (Mobile Ad Hoc Networks) are slowly integrating into our everyday lives, their most prominent uses are visible in the disaster and war struck areas where physical infrastructure is almost impossible or very hard to build. MANETs like other networks are facing the threat of malicious users and their activities. A number of attacks have been identified but the most severe of them is the wormhole attack which has the ability to succeed even in case of encrypted traffic and secure networks. Once wormhole is launched successfully, the severity increases by the fact that attackers can launch other attacks too. This paper presents a comprehensive algorithm for the detection of exposed as well as hidden wormhole attack while keeping the detection rate to maximum and at the same reducing false alarms. The algorithm does not require any extra hardware, time synchronization or any special type of nodes. The architecture consists of the combination of Routing Table, RTT (Round Trip Time) and RSSI (Received Signal Strength Indicator) for comprehensive detection of wormhole attack. The proposed technique is robust, light weight, has low resource requirements and provides real-time detection against the wormhole attack. Simulation results show that the algorithm is able to provide a higher detection rate, packet delivery ratio, negligible false alarms and is also better in terms of Ease of Implementation, Detection Accuracy/ Speed and processing overhead. (author)

Privacy-preserving telecardiology sensor networks: toward a low-cost portable wireless hardware/software codesign.

Science.gov (United States)

Hu, Fei; Jiang, Meng; Wagner, Mark; Dong, De-Cun

2007-11-01

Recently, a remote-sensing platform based on wireless interconnection of tiny ECG sensors called Telecardiology Sensor Networks (TSN) provided a promising approach to perform low-cost real-time cardiac patient monitoring at any time in community areas (such as elder nursing homes or hospitals). The contribution of this research is the design of a practical TSN hardware/software platform for a typical U.S. healthcare community scenario (such as large nursing homes with many elder patients) to perform real-time healthcare data collections. On the other hand, due to the radio broadcasting nature of MANET, a TSN has the risk of losing the privacy of patients' data. Medical privacy has been highly emphasized by U.S. Department of Health and Human Services. This research also designs a medical security scheme with low communication overhead to achieve confidential electrocardiogram data transmission in wireless medium.

Flaubert et la traduction : une vie

Directory of Open Access Journals (Sweden)

Agnès Bouvier

2012-02-01

Full Text Available Ythalonim, vualonuth si chorathisima comsyth,Chym lachchunyth munys thalmyctibari imisciLipho canet hyth bymithii ad aedin bynuthii.Byrnarob syllo homalonin uby misyrthohoBythlym mothym noctothii nelechanti daschmachonYssie brim tyfel yth chylys chon, tem, liphulUth bynim ysdibut thinno cuth nu AgorastoclesYthe manet ihy chyrsae lycoch sith nasoByuni id chil luhili gubylim lasibith thimBodyalyt herayn nyn nuys lym moncoth lusim(Plaute, Poenulus, V, 1– C’est absurde à la fin ! personne ne com...

Wireless Power Control for Tactical MANET: Power Rate Bounds

Science.gov (United States)

2016-09-01

J; P. Hande; T. Lan; C. W. Tan [2008] Power Control in Cellular Networks, Now Publishers Inc., Hanover, MA. 12. Chaves, Fabiano de Sousa; F. R. P...Asymptotically Fast Convergence, IEEE Selected Areas in Communications, 18(3). 36. Jian, Tao; Nicholas D. Sidiropoulos; Georgios B. Giannakis [2003] Kalman...Power Control and Its Imperfections in CDMA Cellular Systems, IEEE Transactions on Vehicular Technologies, 48, pages 1706–1777. 75. Tan , Chee Wei

Dynamic ad hoc networks

CERN Document Server

Rashvand, Habib

2013-01-01

Motivated by the exciting new application paradigm of using amalgamated technologies of the Internet and wireless, the next generation communication networks (also called 'ubiquitous', 'complex' and 'unstructured' networking) are changing the way we develop and apply our future systems and services at home and on local, national and global scales. Whatever the interconnection - a WiMAX enabled networked mobile vehicle, MEMS or nanotechnology enabled distributed sensor systems, Vehicular Ad hoc Networking (VANET) or Mobile Ad hoc Networking (MANET) - all can be classified under new networking s

Contribution to design a communication framework for vehicular ad hoc networks in urban scenarios

OpenAIRE

Tripp Barba, Carolina

2013-01-01

The constant mobility of people, the growing need to be always connected, the large number of vehicles that nowadays can be found in the roads and the advances in technology make Vehicular Ad hoc Networks (VANETs) be a major area of research. Vehicular Ad hoc Networks are a special type of wireless Mobile Ad hoc Networks (MANETs), which allow a group of mobile nodes configure a temporary network and maintain it without the need of a fixed infrastructure. A vehicular network presents some spec...

Routing architecture and security for airborne networks

Science.gov (United States)

Deng, Hongmei; Xie, Peng; Li, Jason; Xu, Roger; Levy, Renato

2009-05-01

Airborne networks are envisioned to provide interconnectivity for terrestial and space networks by interconnecting highly mobile airborne platforms. A number of military applications are expected to be used by the operator, and all these applications require proper routing security support to establish correct route between communicating platforms in a timely manner. As airborne networks somewhat different from traditional wired and wireless networks (e.g., Internet, LAN, WLAN, MANET, etc), security aspects valid in these networks are not fully applicable to airborne networks. Designing an efficient security scheme to protect airborne networks is confronted with new requirements. In this paper, we first identify a candidate routing architecture, which works as an underlying structure for our proposed security scheme. And then we investigate the vulnerabilities and attack models against routing protocols in airborne networks. Based on these studies, we propose an integrated security solution to address routing security issues in airborne networks.

OPTIFER, a further step in development of Low Activation Martensitic Steels. Results of Characterization Experiments

International Nuclear Information System (INIS)

Fernandez, M.P.; Lapena, J.; Hernandez, M.T.; Schirra, M.

1996-01-01

Within the framework of the development of low activation structural materials to be used in nuclear fusion reactors four martensitic Fe-9,5 Cr alloys were conceived with different contentsof tungsten-tantalum and/or germanium as substitutions for Mo, Ni, Nb and Al. As a result of recent activation calculations, the maximum concentrations of all accompanying elements, which are not desirable under radiological aspects, were determined for the first time for these OPTIFER steels, and laid down in specifications for the manufacturers of the alloys. After double-vacuum melting, only the real alloys with some of these accompanying elements added are within the specifications. For the majority of alloys the gap between request in radiological terms and the metallurgical/analytical reality is still considerable. The behavior during transformation and heat treatment roughly corresponds to that of conventional martensitic 9-12degree centigree Cr steels. Progress has been conspicuous as regards the notch impact tougness behavior. Both at upper shelf level and in ductile brittle transition (DBTT) the W(Ce) alloyed OPTIFER variant exhibits more favorable values than the conventional MANET-II steel from the fusion program, with better strength characteristics above 500 degree centigree. With only a moderate decrease in strenght values (compared to MANET-II), the Ge (Ce) variant excels by a distinct improvement in notch impact tougness values and, theoretically, a stronger reduction in dose rate than the W(Ce) variant and comes close to the decay curve of pure iron

OPTIFER, a further step in development of Low Activation Martensitic Steels. Results of Characterization Experiments

International Nuclear Information System (INIS)

Fernandez, M.P.; Lapena, J.; Hernandez, M.T.; Schirra, M.

1996-01-01

Within the framework of the development of low activation structural materials to be used in nuclear fusion reactors four martensitic Fe-9,5 Cr alloys were conceived with different contents of tungsten-tantalum and/or germanium as substitutions for Mo, Ni, Nb and Al. As a result of recent activation calculations, the maximum concentrations of all accompanying elements, which are not desirable under radiological aspects, were determined for the first time for these OPTIFER steels, and laid down in specifications for the manufacturers of the alloys, after double-vacuum melting, only the real alloys with some of these accompanying elements added are within the specifications. For the majority of alloys the gap between request in radiological terms and the metallurgical/analytical reality is still considerable. The behavior during transformation and heat treatment roughly corresponds to that of conventional martensitic 9-12%Cr steels. Progress has been conspicuous as regards the notch impact toughness behavior, both at upper shelf level and in ductile brittle transition (DBTT) the W(Ce) alloyed OPTIFER variant exhibits more favorable values than the conventional MANET-II steel from the fusion program, with better strength characteristics above 500 degree centigree. With only a moderate decrease in strength values (compared to MANET-II), the Ge (Ce) variant excels by a distinct improvement in notch impact toughness values and, theoretically, a stronger reduction in dose rate than the W(Ce) variant and comes close to the decay curve of pure iron. (Author) 21 refs

OPTIFER, a further step in development of Low Activation Martensitic Steels. Results of Characterization Experiments; OPTIFER, un paso mas hacia el desarrollo de un acero martensitico de baja activacion. Resultados de los ensayos de caracterizacion

Energy Technology Data Exchange (ETDEWEB)

Fernandez, M.P.; Lapena, J.; Hernandez, M.T.; Schirra, M.

1996-07-01

Within the framework of the development of low activation structural materials to be used in nuclear fusion reactors four martensitic Fe-9,5 Cr alloys were conceived with different contents of tungsten-tantalum and/or germanium as substitutions for Mo, Ni, Nb and Al. As a result of recent activation calculations, the maximum concentrations of all accompanying elements, which are not desirable under radiological aspects, were determined for the first time for these OPTIFER steels, and laid down in specifications for the manufacturers of the alloys, after double-vacuum melting, only the real alloys with some of these accompanying elements added are within the specifications. For the majority of alloys the gap between request in radiological terms and the metallurgical/analytical reality is still considerable. The behavior during transformation and heat treatment roughly corresponds to that of conventional martensitic 9-12%Cr steels. Progress has been conspicuous as regards the notch impact toughness behavior, both at upper shelf level and in ductile brittle transition (DBTT) the W(Ce) alloyed OPTIFER variant exhibits more favorable values than the conventional MANET-II steel from the fusion program, with better strength characteristics above 500 degree centigree. With only a moderate decrease in strength values (compared to MANET-II), the Ge (Ce) variant excels by a distinct improvement in notch impact toughness values and, theoretically, a stronger reduction in dose rate than the W(Ce) variant and comes close to the decay curve of pure iron. (Author) 21 refs.

Estudio del comportamiento de una red Ad-Hoc MANET metropolitana basado en los protocolos de enrutamiento

Directory of Open Access Journals (Sweden)

Mario Garzón

2011-11-01

Full Text Available En el presente artículo se determina el comportamiento de una red de área metropolitana bajo el estándar IEEE 802.16 tanto para nodos fijos como móviles, utilizando NCTUns, considerando el comportamiento de los protocolos de enrutamiento. Mostrando en los resultados las velocidades de transmisión que se pueden obtener en redes Mesh y la distancia máxima a la cual pueden encontrarse los nodos y la estación radio base.

3VSR: Three Valued Secure Routing for Vehicular Ad Hoc Networks using Sensing Logic in Adversarial Environment

Directory of Open Access Journals (Sweden)

Muhammad Sohail

2018-03-01

Full Text Available Today IoT integrate thousands of inter networks and sensing devices e.g., vehicular networks, which are considered to be challenging due to its high speed and network dynamics. The goal of future vehicular networks is to improve road safety, promote commercial or infotainment products and to reduce the traffic accidents. All these applications are based on the information exchange among nodes, so not only reliable data delivery but also the authenticity and credibility of the data itself are prerequisite. To cope with the aforementioned problem, trust management come up as promising candidate to conduct node’s transaction and interaction management, which requires distributed mobile nodes cooperation for achieving design goals. In this paper, we propose a trust-based routing protocol i.e., 3VSR (Three Valued Secure Routing, which extends the widely used AODV (Ad hoc On-demand Distance Vector routing protocol and employs the idea of Sensing Logic-based trust model to enhance the security solution of VANET (Vehicular Ad-Hoc Network. The existing routing protocol are mostly based on key or signature-based schemes, which off course increases computation overhead. In our proposed 3VSR, trust among entities is updated frequently by means of opinion derived from sensing logic due to vehicles random topologies. In 3VSR the theoretical capabilities are based on Dirichlet distribution by considering prior and posterior uncertainty of the said event. Also by using trust recommendation message exchange, nodes are able to reduce computation and routing overhead. The simulated results shows that the proposed scheme is secure and practical.

3VSR: Three Valued Secure Routing for Vehicular Ad Hoc Networks using Sensing Logic in Adversarial Environment.

Science.gov (United States)

Sohail, Muhammad; Wang, Liangmin

2018-03-14

Today IoT integrate thousands of inter networks and sensing devices e.g., vehicular networks, which are considered to be challenging due to its high speed and network dynamics. The goal of future vehicular networks is to improve road safety, promote commercial or infotainment products and to reduce the traffic accidents. All these applications are based on the information exchange among nodes, so not only reliable data delivery but also the authenticity and credibility of the data itself are prerequisite. To cope with the aforementioned problem, trust management come up as promising candidate to conduct node's transaction and interaction management, which requires distributed mobile nodes cooperation for achieving design goals. In this paper, we propose a trust-based routing protocol i.e., 3VSR (Three Valued Secure Routing), which extends the widely used AODV (Ad hoc On-demand Distance Vector) routing protocol and employs the idea of Sensing Logic-based trust model to enhance the security solution of VANET (Vehicular Ad-Hoc Network). The existing routing protocol are mostly based on key or signature-based schemes, which off course increases computation overhead. In our proposed 3VSR, trust among entities is updated frequently by means of opinion derived from sensing logic due to vehicles random topologies. In 3VSR the theoretical capabilities are based on Dirichlet distribution by considering prior and posterior uncertainty of the said event. Also by using trust recommendation message exchange, nodes are able to reduce computation and routing overhead. The simulated results shows that the proposed scheme is secure and practical.

IF-MANET: Interoperable framework for heterogeneous mobile ad hoc networks

OpenAIRE

Hassan, H.

2015-01-01

The advances in low power micro-processors, wireless networks and embedded systems have raised the need to utilize the significant resources of mobile devices. These devices for example, smart phones, tablets, laptops, wearables, and sensors are gaining enormous processing power, storage capacity and wireless bandwidth. In addition, the advancement in wireless mobile technology has created a new communication paradigm via which a wireless network can be created without any priori infrastructu...

Fighting The Network: Manet Management In Support Of Littoral Operations

Science.gov (United States)

2016-03-01

16 Figure 7. OSI 7-Layer Communication Model ...step towards exploring the complex interface between the two. 18 The Open Systems Interconnection ( OSI ) 7-Layer model provides a reference framework...interfaces. The layers in the OSI model represent seven related groups of functions, as depicted in Figure 7. While these functions are enabled by a

DESAIN ALGORITMA DAN SIMULASI ROUTING UNTUK GATEWAY AD HOC WIRELESS NETWORKS

Directory of Open Access Journals (Sweden)

Nixson Meok

2009-12-01

Full Text Available   Routing protocol to the wireless ad hoc networks is very needed in the communication process between some terminals, to send the data packet through one or several node(s to the destination address where the network typology is always changing. Many previous works that discussed about routing ad hoc both for manet (mobile ad hoc networks and wireless networks, but the emphasis have more focus on comparing the performance of several routing ad hoc. While in this work, there is a bulding of routing algorithm model to gateway in land to the nodes that analogized as a boat that move on the sea. With the assumption that the communication inter terminals to radio band of Very High Frequency, thus algorithm that built in the simulation based on the range gap of the HF frequency. The result of this simulation will be developed as the platform to implement the service development of multiuser communication

Dose determination of 600 MeV proton irradiated specimens

International Nuclear Information System (INIS)

Gavillet, D.

1991-01-01

The calculation method for the experimental determination of the atomic production cross section from the γ activity measurements are presented. This method is used for the determination of some isotope production cross sections for 600 MeV proton irradition in MANET steel, copper, tungsten, gold and titanium. The results are compared with some calculation. These values are used to determine the dose of specimens irradiated in the PIREX II facility. The results are discussed in terms of the irradiation parameters. A guide for the use of the production cross section determined in the dosimetry experiment are given. (author) tabs., refs

Contribution to design a communication framework for vehicular ad hoc networks in urban scenarios

OpenAIRE

Tripp Barba, Carolina

2013-01-01

La movilidad constante de las personas y la creciente necesidad de estar conectados en todo momento ha hecho de las redes vehiculares un área cuyo interés ha ido en aumento. La gran cantidad de vehículos que hay en la actualidad, y los avances tecnológicos han hecho de las redes vehiculares (VANETS, Vehicular Ad hoc Networks) un gran campo de investigación. Las redes vehiculares son un tipo especial de redes móviles ad hoc inalámbricas, las cuales, al igual que las redes MANET (Mobile Ad hoc ...

BPTAP: A New Approach to IP over DTN

Science.gov (United States)

Tsao, Philip; Nguyen, Sam

2012-01-01

Traditional Internet protocols have been widely deployed for a variety of applications. However such protocols generally perform poorly in situations in which, round trip delays are very large (interplanetary distances) or . persistent connectivity is not always available (widely dispersed MANET). Delay/Disruption Tolerant Network (DTN) technology was invented to address these issues: (1) . Relay nodes "take custody" of blocks of network traffic on a hop-by -hop basis and retransmit them in cases of expected or unexpected link outage (2) Bundle lifetime may be configured for long round trip light times. BPTAP is novel by encapsulating Ethernet frames in BP

Design of verification platform for wireless vision sensor networks

Science.gov (United States)

Ye, Juanjuan; Shang, Fei; Yu, Chuang

2017-08-01

At present, the majority of research for wireless vision sensor networks (WVSNs) still remains in the software simulation stage, and the verification platforms of WVSNs that available for use are very few. This situation seriously restricts the transformation from theory research of WVSNs to practical application. Therefore, it is necessary to study the construction of verification platform of WVSNs. This paper combines wireless transceiver module, visual information acquisition module and power acquisition module, designs a high-performance wireless vision sensor node whose core is ARM11 microprocessor and selects AODV as the routing protocol to set up a verification platform called AdvanWorks for WVSNs. Experiments show that the AdvanWorks can successfully achieve functions of image acquisition, coding, wireless transmission, and obtain the effective distance parameters between nodes, which lays a good foundation for the follow-up application of WVSNs.

Routing in IPv6 over Low-Power Wireless Personal Area Networks (6LoWPAN: A Survey

Directory of Open Access Journals (Sweden)

Vinay Kumar

2012-01-01

Full Text Available 6LoWPANs (IPv6-based Low-Power Personal Area Networks are formulated by devices that are compatible with the IEEE 802.15.4 standard. To moderate the effects of network mobility, the Internet Protocol (IP does not calculate routes; it is left to a routing protocol, which maintains routing tables in the routers. 6LowPAN uses an adaptation layer between the network (IPv6 and data link layer (IEEE802.15.4 MAC to fragment and reassemble IPv6 packets. The routing in 6LoWPAN is primarily divided on the basis of routing decision taken on adaptation or network layer. The objective of this paper is to present a state-of-the-art survey of existing routing protocols: LOAD, M-LOAD, DYMO-Low, Hi-Low, Extended Hi-Low, and S-AODV. These routing protocols have compared on the basis of different metric like energy consumption, memory uses, mobility, scalability, routing delay, an RERR message, a Hello message, and local repair. We have also presented the taxonomy of routing requirement; parameter for evaluating routing algorithm, and it was found that the routing protocol has its own advantages depending upon the application where it is used.

On the Tradeoff Between Altruism and Selfishness in MANET Trust Management

Science.gov (United States)

2016-04-07

network deployment, we assume that there is no predefined trust . Without prior interactions, the initial bootstrapping will establish a shallow level of...a challenge/response process (e.g., public key authentication). Over time, partic- ipating nodes will establish a stronger trust level with more...periodically. This will enable each node to compute trust values of other nodes considering the original recommen- dations from the 1-hop neighbors of

Influence of materials choice on occupational radiation exposure in ITER

International Nuclear Information System (INIS)

Forty, C.B.A.; Firth, J.D.; Butterworth, G.J.

1998-01-01

In fission reactor plant, the radiation doses associated with inspection and maintenance of the primary cooling circuit account for a substantial fraction of the collective occupational radiation exposure (ORE). Similarly, it is anticipated that much of the ORE occurring during normal operation of ITER will arise from active deposits in the cooling loop. Using a number of calculation steps ranging from neutron activation analysis, mobilisation and transport modelling and Monte Carlo simulation, estimates for the gamma photon flux and radiation dose fields around a typical 'hot-leg' cooling pipe have been made taking SS316, OPTSTAB, MANET-II and F-82H steels as alternative candidate loop materials. (orig.)

NOBAI: a web server for character coding of geometrical and statistical features in RNA structure

Science.gov (United States)

Knudsen, Vegeir; Caetano-Anollés, Gustavo

2008-01-01

The Numeration of Objects in Biology: Alignment Inferences (NOBAI) web server provides a web interface to the applications in the NOBAI software package. This software codes topological and thermodynamic information related to the secondary structure of RNA molecules as multi-state phylogenetic characters, builds character matrices directly in NEXUS format and provides sequence randomization options. The web server is an effective tool that facilitates the search for evolutionary history embedded in the structure of functional RNA molecules. The NOBAI web server is accessible at ‘http://www.manet.uiuc.edu/nobai/nobai.php’. This web site is free and open to all users and there is no login requirement. PMID:18448469

Un autoportrait de Berthe Morisot

OpenAIRE

Bonnet, Marie-Jo

2006-01-01

À voir la détermination avec laquelle Berthe Morisot nous regarde, nous pourrions penser qu’elle a trouvé facilement sa place d’artiste. Une palette est esquissée sur la gauche de trois mouvements tournants. Elle porte une fleur bleue à la boutonnière, «  comme une décoration  », dira Mallarmé, elle se tient droite, la tête tournée vers le spectateur, et elle nous regarde de ses célèbres yeux noirs qui ont tant fasciné Manet. Paul Valéry écrira d’ailleurs au sujet de ses yeux  : «  Berthe Mor...

Comparison of TEAR and TFRC throughput for Drop tail and RED Queue Management Techniques

Directory of Open Access Journals (Sweden)

Parminderjeet Singh

2014-12-01

Full Text Available The comparison of throughput for TEAR (TCP emulation at receivers and TFRC TCP friendly rate control in MANETs is done with varying Active queue Management Techniques. The analysis reveals that for bandwidth constraint links, TEAR and TFRC perform far better than normal traffic propagation through TCP. In case of TEAR, the processing and route congestion algorithm load is shared by the receiver resulting in lesser load at the transmitters. In TFRC the TCP traffic is propagated via an algorithm to curb acknowledgement congestions. The effect of these two techniques is monitored on Droptail and RED, two of the most common Active Queue Management Techniques.

Design and Implementation of a Mobile Multihop WSN for AGV System

Directory of Open Access Journals (Sweden)

Jiaqi Zhang

2010-01-01

Full Text Available A system data sharing protocol of mobile WSN named synchronous dynamic multihop data sharing protocol (S-DMDS is presented for automated guided vehicle (AGV system. It is a cross-layer protocol designed from route layer to MAC layer. By adopting a concept of system data sharing, it is possible to make each node exchange the data timely with all the other nodes. It is also a topology-agnostic protocol which has no knowledge of neighbors, routes, or next hops. From the results of the 16-nodes simulation, S-DMDS protocol is proved to be efficient exchange data timely between the devices of AGV system in mobile multihop situation. Moreover, it also shows that S-DMDS significantly outperforms NST-AODV with investing about 41.6% system sharing delay as well as 80% RAM consumption. At last, 5-node experiment indicates that S-DMDS can work well in real environment.

Cyber threat model for tactical radio networks

Science.gov (United States)

Kurdziel, Michael T.

2014-05-01

The shift to a full information-centric paradigm in the battlefield has allowed ConOps to be developed that are only possible using modern network communications systems. Securing these Tactical Networks without impacting their capabilities has been a challenge. Tactical networks with fixed infrastructure have similar vulnerabilities to their commercial counterparts (although they need to be secure against adversaries with greater capabilities, resources and motivation). However, networks with mobile infrastructure components and Mobile Ad hoc Networks (MANets) have additional unique vulnerabilities that must be considered. It is useful to examine Tactical Network based ConOps and use them to construct a threat model and baseline cyber security requirements for Tactical Networks with fixed infrastructure, mobile infrastructure and/or ad hoc modes of operation. This paper will present an introduction to threat model assessment. A definition and detailed discussion of a Tactical Network threat model is also presented. Finally, the model is used to derive baseline requirements that can be used to design or evaluate a cyber security solution that can be scaled and adapted to the needs of specific deployments.

An authenticated encrypted routing protocol against attacks in mobile ad-hoc networks

Directory of Open Access Journals (Sweden)

C.C. Suma

2017-01-01

Full Text Available Mobile Ad hoc Network is stated as a cluster that contains Digital data terminals and they are furnished with the wireless transceivers which are able to communicate with each other with no need of any fixed architecture or concentrated authority. Security is one of the major issues in MANETs because of vast applications such as Military Battlefields, emergency and rescue operations[10]. In order to provide anonymous communications and to identify the malicious nodes in MANETs, many authors have proposed different secure routing protocols but each protocol have their own advantages and disadvantages. In MANTE’s each and every node in the communicating network functions like router and transmits the packets among the networking nodes for the purpose of communication[11]. Sometimes nodes may be attacked by the malicious nodes or the legitimate node will be caught by foemen there by controlling and preventing the nodes to perform the assigned task or nodes may be corrupted due to loss of energy. So, due to these drawbacks securing the network under the presence of adversaries is an important thing. The existing protocols were designed with keeping anonymity and the identification of vicious nodes in the network as the main goal. For providing better security, the anonymity factors such as Unidentifiability and Unlinkability must be fully satisfied[1]. Many anonymous routing schemes that concentrate on achieving anonymity are proposed in the past decade and they provides the security at different levels and also provides the privacy protection that is of different cost. In this paper we consider a protocol called Authenticated Secure Routing Protocol proposed which provides both security & anonymity. Anonymity is achieved in this protocol using Group signature. Over all by using this protocol performance in terms of throughput as well as the packet dropping rate is good compared to the other living protocols.

Principles of mobile computing and communications

CERN Document Server

Othman, Mazliza

2007-01-01

Introduction Mobile Computing Applications Evolution of Wireless Networks and Services Summary Cellular Network Architecture UMTS Architecture Public Land Mobile Network Interfaces User Authentication Frequency Reuse Channel Assignment Location Registration and Update Handover Procedures CDMA The Move toward 3G Networks Wireless Local Area Networks IEEE 802.11 Standard IEEE 802.11b Standard (Wi-Fi) IEEE 802.11a Standard IEEE 802.11g Standard HIPERLAN/2 IEEE 802.1x Standard IEEE 802.11i Standard IEEE 802.11e Standard Security Issues IP over 802.11 WLAN Integrating 802.11 WLAN and UMTS Summary Wireless Personal Area Networks HomeRF Bluetooth Technology IEEE 802.15.3 Standard Home Area Networks Summary Wireless Sensor Networks Applications of WSNs Requirements for WSNs WSN Architecture The 802.15.4 Standard The ZigBee Protocol Power Conservation Techniques Network and Communications Configuration of Sensor Networks WSN and Emergency Response Applications Summary Mobile Ad Hoc Networks AODV DSR OLSR TBRPF Summary...

A Novel Routing Algorithm for Vehicular Ad Hoc Networks

Directory of Open Access Journals (Sweden)

Raúl Aquino Santos

2008-01-01

Full Text Available Este trabajo examina la importancia de las redes inalámbricas ad hoc y el algoritmo de enrutamiento con inundación basada en grupos (LORA-CBF para la comunicación inter-vehicular con la finalidad de optimizar el flujo de tráfico e incrementar la seguridad en las autopistas. Se discute el algoritmo de enrutamiento LORA-CBF y se presentan los resultados de simulaciones realizadas en OPNET de una autopista con alta movilidad vehicular. Primero, el modelo de simulación propuesto se valida a pequeña escala con resultados experimentales. Posteriormente, se emplean simulaciones de nuestro modelo comparándolos con Ad Hoc On-Demand Distance Vector (AODV y Dynamic Source Routing (DSR. Finalmente, se emplea un modelo de tráfico microscópico desarrollado en OPNET para simular la movilidad de 250 vehículos en una autopista y se aplica el algoritmo de enrutamiento LORA-CBF en un escenario vehicular.

Evaluating the More Suitable ISM Frequency Band for IoT-Based Smart Grids: A Quantitative Study of 915 MHz vs. 2400 MHz

Directory of Open Access Journals (Sweden)

Ruben M. Sandoval

2016-12-01

Full Text Available IoT has begun to be employed pervasively in industrial environments and critical infrastructures thanks to its positive impact on performance and efficiency. Among these environments, the Smart Grid (SG excels as the perfect host for this technology, mainly due to its potential to become the motor of the rest of electrically-dependent infrastructures. To make this SG-oriented IoT cost-effective, most deployments employ unlicensed ISM bands, specifically the 2400 MHz one, due to its extended communication bandwidth in comparison with lower bands. This band has been extensively used for years by Wireless Sensor Networks (WSN and Mobile Ad-hoc Networks (MANET, from which the IoT technologically inherits. However, this work questions and evaluates the suitability of such a “default” communication band in SG environments, compared with the 915 MHz ISM band. A comprehensive quantitative comparison of these bands has been accomplished in terms of: power consumption, average network delay, and packet reception rate. To allow such a study, a dual-band propagation model specifically designed for the SG has been derived, tested, and incorporated into the well-known TOSSIM simulator. Simulation results reveal that only in the absence of other 2400 MHz interfering devices (such as WiFi or Bluetooth or in small networks, is the 2400 MHz band the best option. In any other case, SG-oriented IoT quantitatively perform better if operating in the 915 MHz band.

Evaluating the More Suitable ISM Frequency Band for IoT-Based Smart Grids: A Quantitative Study of 915 MHz vs. 2400 MHz.

Science.gov (United States)

Sandoval, Ruben M; Garcia-Sanchez, Antonio-Javier; Garcia-Sanchez, Felipe; Garcia-Haro, Joan

2016-12-31

IoT has begun to be employed pervasively in industrial environments and critical infrastructures thanks to its positive impact on performance and efficiency. Among these environments, the Smart Grid (SG) excels as the perfect host for this technology, mainly due to its potential to become the motor of the rest of electrically-dependent infrastructures. To make this SG-oriented IoT cost-effective, most deployments employ unlicensed ISM bands, specifically the 2400 MHz one, due to its extended communication bandwidth in comparison with lower bands. This band has been extensively used for years by Wireless Sensor Networks (WSN) and Mobile Ad-hoc Networks (MANET), from which the IoT technologically inherits. However, this work questions and evaluates the suitability of such a "default" communication band in SG environments, compared with the 915 MHz ISM band. A comprehensive quantitative comparison of these bands has been accomplished in terms of: power consumption, average network delay, and packet reception rate. To allow such a study, a dual-band propagation model specifically designed for the SG has been derived, tested, and incorporated into the well-known TOSSIM simulator. Simulation results reveal that only in the absence of other 2400 MHz interfering devices (such as WiFi or Bluetooth) or in small networks, is the 2400 MHz band the best option. In any other case, SG-oriented IoT quantitatively perform better if operating in the 915 MHz band.

Performance and energy efficiency in wireless self-organized networks

Energy Technology Data Exchange (ETDEWEB)

Gao, C.

2009-07-01

Self-organized packet radio networks (ad-hoc networks) and wireless sensor networks have got massive attention recently. One of critical problems in such networks is the energy efficiency, because wireless nodes are usually powered by battery. Energy efficiency design can dramatically increase the survivability and stability of wireless ad-hoc/sensor networks. In this thesis the energy efficiency has been considered at different protocol layers for wireless ad-hoc/sensor networks. The energy consumption of wireless nodes is inspected at the physical layer and MAC layer. At the network layer, some current routing protocols are compared and special attention has been paid to reactive routing protocols. A minimum hop analysis is given and according to the analysis result, a modification of AODV routing is proposed. A variation of transmit power can be also applied to clustering algorithm, which is believed to be able to control the scalability of network. Clustering a network can also improve the energy efficiency. We offer a clustering scheme based on the link state measurement and variation of transmit power of intra-cluster and inter-cluster transmission. Simulation shows that it can achieve both targets. In association with the clustering algorithm, a global synchronization scheme is proposed to increase the efficiency of clustering algorithm. The research attention has been also paid to self-organization for multi-hop cellular networks. A 2-hop 2-slot uplink proposal to infrastructure-based cellular networks. The proposed solution can significantly increase the throughput of uplink communication and reduce the energy consumption of wireless terminals. (orig.)

嵌入服务通告与发现的ZRP协议%Embedded Service Advertisement and Discovery in ZRP Protocol

Institute of Scientific and Technical Information of China (English)

李志远

2008-01-01

服务通告和发现在MANET(Mobile Ad hoc Networks)网络中,是一个十分重要的组成部分.现有的服务通告和发现协议不是为MANET网络设计的.文章提出了一个适合MANET、基于ZRP(Zone Routing Protocol)的服务通告及发现协议.服务的通告与发现存在于ZRP路由控制分组中,避免了周期性的通告给MANET网络带来的负载,节约了有限的带宽和设备的能耗.

A New Approach to Predict user Mobility Using Semantic Analysis and Machine Learning.

Science.gov (United States)

Fernandes, Roshan; D'Souza G L, Rio

2017-10-19

Mobility prediction is a technique in which the future location of a user is identified in a given network. Mobility prediction provides solutions to many day-to-day life problems. It helps in seamless handovers in wireless networks to provide better location based services and to recalculate paths in Mobile Ad hoc Networks (MANET). In the present study, a framework is presented which predicts user mobility in presence and absence of mobility history. Naïve Bayesian classification algorithm and Markov Model are used to predict user future location when user mobility history is available. An attempt is made to predict user future location by using Short Message Service (SMS) and instantaneous Geological coordinates in the absence of mobility patterns. The proposed technique compares the performance metrics with commonly used Markov Chain model. From the experimental results it is evident that the techniques used in this work gives better results when considering both spatial and temporal information. The proposed method predicts user's future location in the absence of mobility history quite fairly. The proposed work is applied to predict the mobility of medical rescue vehicles and social security systems.

Methods for reliability evaluation of trust and reputation systems

Science.gov (United States)

Janiszewski, Marek B.

2016-09-01

Trust and reputation systems are a systematic approach to build security on the basis of observations of node's behaviour. Exchange of node's opinions about other nodes is very useful to indicate nodes which act selfishly or maliciously. The idea behind trust and reputation systems gets significance because of the fact that conventional security measures (based on cryptography) are often not sufficient. Trust and reputation systems can be used in various types of networks such as WSN, MANET, P2P and also in e-commerce applications. Trust and reputation systems give not only benefits but also could be a thread itself. Many attacks aim at trust and reputation systems exist, but such attacks still have not gain enough attention of research teams. Moreover, joint effects of many of known attacks have been determined as a very interesting field of research. Lack of an acknowledged methodology of evaluation of trust and reputation systems is a serious problem. This paper aims at presenting various approaches of evaluation such systems. This work also contains a description of generalization of many trust and reputation systems which can be used to evaluate reliability of such systems in the context of preventing various attacks.

An Approach to Ad-hoc Messaging Networks Using Time Shifted Propagation

Directory of Open Access Journals (Sweden)

Christoph Fuchß

2007-10-01

Full Text Available Many communication devices, like mobile phones and PDAs, are enabled for near field communication by using Bluetooth. Many approaches dealt so far with the attempt to transfer mobile ad-hoc networks (MANET to the mechanism of the “fixed internet” to mobile networks. In order to achieve liability and robustness of common TCP connections routing algorithm in near field communication based networks become more sophisticated and complex. These mechanisms often do not reflect on the application’s particularities.Our approach of an ad-hoc messaging network (AMNET uses simple store-and-forward message passing to spread data asynchronously. We do not aim at the reliability of common internet networks but focus on application specific needs that can be covered by simple message passing mechanism. In this paper we will portray a powerful network by using simple devices and communication protocols on the basis of AMNETs. Simulation results of our AMNET approach provide insights towards speeding up the network setup process and to enable the use of AMNETs even with few participants by introducing a hybrid structure of infrastructure and mobile nodes.

Aluminium-rich coatings as tritium permeation barriers on MANET (1.4914) stainless steel

International Nuclear Information System (INIS)

Terlain, A.; De Vito, E.

1994-01-01

Al-rich coatings on 1.4914 martensitic steel, produced by different techniques, have been investigated with optical and scanning electron microscopy, X-ray fluorescence and X-ray photoelectron spectroscopy. Tests for their Pb-17Li compatibility and thermo cycling behaviours have been performed on some coated specimens. Up to now, none of the investigated coatings can be eliminated on the basis of the tests and analyses performed. Further work is required to adapt 1.4914 steel coating techniques to fusion reactor requirements. (author) 9 refs.; 5 figs.; 1 tab

A distributed Synchronous reservation multiple access control protocol for mobile Ad hoc networks

Institute of Scientific and Technical Information of China (English)

ZHANG Yanling; SUN Xianpu; LI Jiandong

2007-01-01

This study proposes a new multiple access control protocol named distributed synchronous reservation multiple access control protocol.in which the hidden and exposed terminal problems are solved,and the quality of service(QoS)requirements for real-time traffic are guaranteed.The protocol is founded on time division multiplex address and a different type of traffic is assigned to difierent priority,according to which a node should compete for and reserve the free slots in a different method.Moreover,there is a reservation acknowledgement process before data transmit in each reserved slot,so that the intruded terminal problem is solved.The throughput and average packets drop probability of this protocol are analyzed and simulated in a fully connected network.the results of which indicate that this protocol is efficient enough to support the real-time traffic.and it is more suitable to MANETs.

Leveraging Manet and Mobile Devices in Ship-to-Objective Maneuver and Expeditionary MAGTF Operations

Science.gov (United States)

2014-09-01

support and firepower. ECO allows for the Marine Corps to deploy a lower- level maneuver unit as an economy of force measure to assert combat power over...to the Global Information Grid ( GIG ) is the course of action the Marine Corps should adopt (Price & McHuen, 2009). My proposed research addresses

Mobility-Assisted on-Demand Routing Algorithm for MANETs in the Presence of Location Errors

Directory of Open Access Journals (Sweden)

Trung Kien Vu

2014-01-01

Full Text Available We propose a mobility-assisted on-demand routing algorithm for mobile ad hoc networks in the presence of location errors. Location awareness enables mobile nodes to predict their mobility and enhances routing performance by estimating link duration and selecting reliable routes. However, measured locations intrinsically include errors in measurement. Such errors degrade mobility prediction and have been ignored in previous work. To mitigate the impact of location errors on routing, we propose an on-demand routing algorithm taking into account location errors. To that end, we adopt the Kalman filter to estimate accurate locations and consider route confidence in discovering routes. Via simulations, we compare our algorithm and previous algorithms in various environments. Our proposed mobility prediction is robust to the location errors.

Estimation of trust metrics for MANET using QoS parameter and source routing algorithms

CSIR Research Space (South Africa)

Umuhoza, D

2007-08-01

Full Text Available parameters. Probabilities of transit time variation, deleted, multiplied and inserted packets, processing delays are used to estimate and update trust. Functions which facilitate this are provided and evaluated. It has been shown that only two end nodes need...

ANÁLISIS ACERCA DE LA IMPLEMENTACIÓN DE SISTEMAS DE VIDEO VIGILANCIA SOBRE REDES MESH

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Christian Fuquene

2012-05-01

Full Text Available En  los  últimos  años  las  redes  Ad-hoc  Mesh,  han  estado  atrayendo la atención por su uso potencial en varios campos  tales  como  las  actividades  militares,  operaciones  de  rescate  y  aplicaciones  en  tiempo  crítico.  En  este  artículo  se presenta el análisis de la implementación de un sistema  de  video  vigilancia  para  sectores  marginados  de  Bogotá  usando  redes  Ad-hoc  Mesh.  Se  describen  los  protocolos  más usados internacionalmente AODV, OLSR, BATMAN y se  comparan para seleccionar el más óptimo. De igual forma se  selecciona de una extensa lista de hardware el router con el  mejor costo beneficio que se adecua al firmware nightwing.  Al final se relacionan los costos de implementación de un escenario cableado contra un escenario inalámbrico que ofrecen sistemas de video vigilancia.

The Comparative Study Some of Reactive and Proactive Routing Protocols in The Wireless Sensor Network

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Anas Ali Hussien

2018-02-01

Full Text Available The wireless sensor network (WSN consists mostly of a large number of nodes in a large area where not all nodes are directly connected. The applications of comprise a wide variety of scenarios.The mobile nodes are free to move because this network has selfــstructured topology. Routing protocols are responsible for detecting and maintaining paths in the network, and it classified into reactive (OnـــDemand, proactive (Table driven, and hybrid. In this paper represents a performance study of some WSN routing protocols: the Dynamic Source Routing (DSR, Ad hoc On-Demand Distance Vector (AODV, and Destination-Sequenced Distance-Vector (DSDV. The comparison made according to important metrics like packet delivery ratio (PDR, total packets dropped, Average end-to-end delay (Avg EED, and normalized routing load under the Transmission Control Protocol (TCP and User Datagram Protocol (UDP traffic connection and with varying number of nodes, pause time; and  varying speed. In this work used (NSــ2.35 that installed on (Ubuntu 14.04 operating system to implementing the scenario. Conclude that the DSR has better performance in TCP connection; while the DSDV has better performance in UDP protocol.

OPNET Modeler Simulation Testing of the New Model Used to Cooperation Between QoS and Security Mechanisms

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Jan Papaj

2012-01-01

Full Text Available In this article the performance analysis of the new model, used to integration between QoS and Security, is introduced. OPNET modeler simulation testing of the new model with comparation with the standard model is presented. This new model enables the process of cooperation between QoS and Security in MANET. The introduction how the model is implemented to the simulation OPNET modeler is also showed. Model provides possibilities to integration and cooperation of QoS and security by the cross layer design (CLD with modified security service vector (SSV. An overview of the simulation tested of the new model, comparative study in mobile ad-hoc networks, describe requirements and directions for adapted solutions are presented. Main idea of the testing is to show how QoS and Security related services could be provided simultaneously with using minimal interfering with each service.

Evolutionary algorithms for mobile ad hoc networks

CERN Document Server

Dorronsoro, Bernabé; Danoy, Grégoire; Pigné, Yoann; Bouvry, Pascal

2014-01-01

Describes how evolutionary algorithms (EAs) can be used to identify, model, and minimize day-to-day problems that arise for researchers in optimization and mobile networking. Mobile ad hoc networks (MANETs), vehicular networks (VANETs), sensor networks (SNs), and hybrid networks—each of these require a designer’s keen sense and knowledge of evolutionary algorithms in order to help with the common issues that plague professionals involved in optimization and mobile networking. This book introduces readers to both mobile ad hoc networks and evolutionary algorithms, presenting basic concepts as well as detailed descriptions of each. It demonstrates how metaheuristics and evolutionary algorithms (EAs) can be used to help provide low-cost operations in the optimization process—allowing designers to put some “intelligence” or sophistication into the design. It also offers efficient and accurate information on dissemination algorithms topology management, and mobility models to address challenges in the ...

P-T data from central Bhutan imply distributed extensional shear at the Black Mountain "klippe"

Science.gov (United States)

Corrie, S. L.; Kohn, M. J.; Long, S. P.; McQuarrie, N.; Tobgay, T.

2011-12-01

The Southern Tibetan Detachment system (STDS) occurs along the entire length of the Himalayan orogen, and extensionally emplaces low-grade to unmetamorphosed Tethyan Himalayan (TH) rocks over highly metamorphosed Greater Himalayan sequence (GH) rocks. The base of TH remnants preserved in northern Bhutan all have top-to-the-north shear sense indicators (C'-type shear bands, asymmetric folds, and boudinaged leucogranite dikes) that are interpreted to reflect a discrete shear zone. In contrast, the GH-TH contact in the southernmost TH remnant (the Black Mountain region, central Bhutan) has been interpreted as depositional. A depositional contact limits the magnitude of displacement along the early STDS to 10's of km. If the GH-TH contact in the Black Mountain region is instead a discrete shear zone, as observed farther north, displacement on the STDS could be as high as 100's of km. To discriminate between these two interpretations, we determined peak metamorphic P-T conditions through the GH and TH sections, reasoning that a discrete shear zone would produce a distinct jump in metamorphic temperature, pressure or both. Thin section-scale kinematic indicators reveal pervasive top-to-the-north shear from 2-3 km structurally above the Main Central thrust (MCT) through the rest of the 11 km thick GH and TH sections. P-T conditions were determined from immediately above the MCT to 4 km above the GH-TH contact, with 19 samples from the GH, 6 from the overlying Chekha Fm (TH), and 9 from the overlying Maneting Fm (TH). We applied standard Fe-Mg exchange thermometers and Ca net-transfer barometers involving garnet. P-T conditions range from 700 °C and 11 kbar in migmatitic GHS to 600 °C and 8 kbar at the GH-Chekha contact, and 500 °C and 5 kbar at the top of the Maneting. We found no jumps in either temperature or pressure at any level, but a steeper than lithostatic pressure gradient, which we interpret to result from distributed extensional shear. The average thermal

Cooperation as a Service in VANET: Implementation and Simulation Results

Directory of Open Access Journals (Sweden)

Hajar Mousannif

2012-01-01

Full Text Available The past decade has witnessed the emergence of Vehicular Ad-hoc Networks (VANET, specializing from the well-known Mobile Ad Hoc Networks (MANET to Vehicle-to-Vehicle (V2V and Vehicle-to-Infrastructure (V2I wireless communications. While the original motivation for Vehicular Networks was to promote traffic safety, recently it has become increasingly obvious that Vehicular Networks open new vistas for Internet access, providing weather or road condition, parking availability, distributed gaming, and advertisement. In previous papers [27,28], we introduced Cooperation as a Service (CaaS; a new service-oriented solution which enables improved and new services for the road users and an optimized use of the road network through vehicle's cooperation and vehicle-to-vehicle communications. The current paper is an extension of the first ones; it describes an improved version of CaaS and provides its full implementation details and simulation results. CaaS structures the network into clusters, and uses Content Based Routing (CBR for intra-cluster communications and DTN (Delay–and disruption-Tolerant Network routing for inter-cluster communications. To show the feasibility of our approach, we implemented and tested CaaS using Opnet modeler software package. Simulation results prove the correctness of our protocol and indicate that CaaS achieves higher performance as compared to an Epidemic approach.

Scalable Mobile Ad Hoc Network (MANET) to Enhance Situational Awareness in Distributed Small Unit Operations

Science.gov (United States)

2015-06-01

computing the algorithm is written in Python, a simple terminal programming language. At the top of that script was the integration to ROS and the rest of...etError    (1) where the refresh frequency is represented by Network in units of Hz and the angular speed of the Marine’s sweep rate...starts with: Java , C++, Python, and more. There are literally thousands if not hundreds of thousands, of projects, platforms, sensors, actuators

Increased longevity of wireless Ad hoc network through fuzzy system

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Fawzia Abdali Larki

2014-06-01

Full Text Available The Ad hoc network is one of the multistep-based self-organizing networks, which are dynamically changing and are taken more into account as the ways of connecting the terminals through the development of wireless communication terminals. We are faced with numerous challenges in designing a wireless network such as the dynamic topology, common and limited bandwidth, and the limited energy. The nodes are moving according to the continuous changes in the topology and the source-to-destination paths are completely broken. Therefore, the repeated route discovery enhances the delay and overload of routing. Thus, it is essential to consider the link stability while designing the path in order to choose the routing protocol. Providing the multiple paths may lead to the better performance than a path. The transmission energy control in the wireless Ad hoc networks is the option for the level of transmission energy in order to transmit each node packet in this system. Therefore, transmission energy control affects the wireless medium interface. Because of choosing the appropriate protocol, the routing operation can be improved and the energy consumption can be controlled properly as well as enhancing the durability and longevity of network. The main objective of this study is to enhance the network longevity. The proposed algorithm in this research considers the combination of 2 parameters including the rate of node energy and number of steps in Fuzzy System applied on AOMDV Protocol, which is a Multipath Routing Protocol. The results of simulation also indicate the improved performance of proposed algorithm (AOMDV-F compared to AODV and AOMDV Protocols in NS2 simulator.

Identifying Time Measurement Tampering in the Traversal Time and Hop Count Analysis (TTHCA Wormhole Detection Algorithm

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Jonny Karlsson

2013-05-01

Full Text Available Traversal time and hop count analysis (TTHCA is a recent wormhole detection algorithm for mobile ad hoc networks (MANET which provides enhanced detection performance against all wormhole attack variants and network types. TTHCA involves each node measuring the processing time of routing packets during the route discovery process and then delivering the measurements to the source node. In a participation mode (PM wormhole where malicious nodes appear in the routing tables as legitimate nodes, the time measurements can potentially be altered so preventing TTHCA from successfully detecting the wormhole. This paper analyses the prevailing conditions for time tampering attacks to succeed for PM wormholes, before introducing an extension to the TTHCA detection algorithm called ∆T Vector which is designed to identify time tampering, while preserving low false positive rates. Simulation results confirm that the ∆T Vector extension is able to effectively detect time tampering attacks, thereby providing an important security enhancement to the TTHCA algorithm.

Postirradiation thermocyclic loading of ferritic-martensitic structural materials

Science.gov (United States)

Belyaeva, L.; Orychtchenko, A.; Petersen, C.; Rybin, V.

Thermonuclear fusion reactors of the Tokamak-type will be unique power engineering plants to operate in thermocyclic mode only. Ferritic-martensitic stainless steels are prime candidate structural materials for test blankets of the ITER fusion reactor. Beyond the radiation damage, thermomechanical cyclic loading is considered as the most detrimental lifetime limiting phenomenon for the above structure. With a Russian and a German facility for thermal fatigue testing of neutron irradiated materials a cooperation has been undertaken. Ampule devices to irradiate specimens for postirradiation thermal fatigue tests have been developed by the Russian partner. The irradiation of these ampule devices loaded with specimens of ferritic-martensitic steels, like the European MANET-II, the Russian 05K12N2M and the Japanese Low Activation Material F82H-mod, in a WWR-M-type reactor just started. A description of the irradiation facility, the qualification of the ampule device and the modification of the German thermal fatigue facility will be presented.

Water-cooled Pb-17Li test blanket module for ITER: impact of the structural material grade on the neutronic responses

Energy Technology Data Exchange (ETDEWEB)

Vella, G.; Aiello, G.; Oliveri, E. [Palermo Univ. (Italy). Dipt. di Ingegneria Nucl.; Fuetterer, M.A.; Giancarli, L. [CEA - Saclay, DRN/DMT/SERMA, Gif-sur-Yvette (France); Tavassoli, F. [CEA - Saclay, CEREM, Gif-sur-Yvette (France)

1998-10-01

The water-cooled lithium lead (WCLL) DEMO blanket is one of the two EU lines to be further developed with the aim of manufacturing by 2010 a test blanket module for ITER (TBM). In this paper results of a 3D-Monte Carlo neutronic analysis of the TBM design are reported. A fully 3D heterogeneous model of the WCLL-TBM has been inserted into an existing ITER model accounting for a proper D-T neutron source. The structural material assumed for the calculations was martensitic 9% Cr steel code named Z 10 CDV Nb 9-1. Results have been compared with those obtained using MANET. The main nuclear responses of the TBM have been determined, such as detailed power deposition density, material damage through DPA and He and H gas production rate, radial distribution of tritium production rate and total tritium production in the module. The impact of using natural lithium on the TBM system operation has also been evaluated. (orig.) 13 refs.

A análise do discurso diante de estranhos espelhos: visualidade e (interdiscursividade na pintura

Directory of Open Access Journals (Sweden)

Renan Belmonte Mazzola

2013-11-01

Full Text Available Este artigo intenciona compreender a dimensão discursiva das pinturas por meio da análise do discurso ancorada em Michel Foucault. Recorta-se a figura do espelho em pinturas canônicas com vistas a observar seu funcionamento discursivo enquanto elemento do enunciado artístico visual. Apresenta três partes: a primeira, que determina o lugar ocupado pelo discurso estético nos trabalhos de Michel Pêcheux e de Michel Foucault; a segunda, que se concentra na análise de três pinturas europeias, a saber, As meninas, de Velásquez; Um bar em Folies-Bergère, de Manet; e As ligações perigosas, de Magritte; e a terceira parte, que discute a intersecção entre visualidade e interdiscursividade a partir (a das reflexões de M. Foucault acerca do discurso estético e (b da figura do espelho presente nessas pinturas.

Emerging Radio and Manet Technology Study: Research Support for a Survey of State-of-the-art Commercial and Military Hardware/Software for Mobile Ad Hoc Networks

Science.gov (United States)

2014-10-01

Exynos 4412 Prime, 1.17GHz ARMS Cortex -A9 quad core processor . It features Ethernet, 2x USB ports, audio, power connectors, micro HDMI, and micro SD...uses a camera mounted on the soldier’s helmet and a Harris video processor to gather and share video over the radio network. 3.1.1.4 Thales Group...on ARM processors . There are a limited few based on MIPS processors but they are uncommon and not well supported. This is in contrast to routers

Behavior of steels in flowing liquid PbBi eutectic alloy at 420-600 deg. C after 4000-7200 h

International Nuclear Information System (INIS)

Mueller, G.; Heinzel, A.; Konys, J.; Schumacher, G.; Weisenburger, A.; Zimmermann, F.; Engelko, V.; Rusanov, A.; Markov, V.

2004-01-01

This paper presents the results of steel exposure up to 7200 h in flowing LBE at elevated temperatures and is a follow-up paper of that with results of an exposure of up to 2000 h. The examined AISI 316 L, 1.4970 austenitic and MANET 10Cr martensitic steels are suitable as a structural material in LBE (liquid eutectic Pb 45 Bi 55 ) up to 550 deg. C, if 10 -6 wt% of oxygen is dissolved in the LBE. The martensitic steel develops a thick magnetite and spinel layer while the austenites have thin spinel surface layers at 420 deg. C and thick oxide scales like the martensitic steel at 550 deg. C. The oxide scales protect the steels from dissolution attack by LBE during the whole test period of 7200 h. Oxide scales that spall off are replaced by new protective ones. At 600 deg. C severe attack occurs already after 2000 and 4000 h of exposure. Steels with 8-15 wt% Al alloyed into the surface suffer no corrosion attack at all experimental temperatures and exposure times

A Time-Slotted On-Demand Routing Protocol for Mobile Ad Hoc Unmanned Vehicle Systems

Energy Technology Data Exchange (ETDEWEB)

Hope Forsmann; Robert Hiromoto; John Svoboda

2007-04-01

The popularity of UAVs has increased dramatically because of their successful deployment in military operations, their ability to preserve human life, and the continual improvements in wireless communication that serves to increase their capabilities. We believe the usefulness of UAVs would be dramatically increased if formation flight were added to the list of capabilities. Currently, sustained formation flight with a cluster of UAVs has only been achieved with two nodes by the Multi-UAV Testbed at the Massachusetts Institute of Technology. (Park, 2004) Formation flight is a complex operation requiring the ability to adjust the flight patterns on the fly and correct for wind gusts, terrain, and differences in node equipment. All of which increases the amount of inner node communication. Since one of the problems with MANET communication is network congestion, we believe a first step towards formation flight can be made through improved inner node communication. We have investigated current communication routing protocols and developed an altered hybrid routing protocol in order to provide communication with less network congestion.

[Pierre Bourdieu: sociology as a "symbolic revolution"].

Science.gov (United States)

Suaud, Charles

2014-03-01

The article combines two objectives: understand the genesis and development of the sociology of Bourdieu in connection with his social and intellectual positioning. The sociology of Bourdieu is a theory of Action which reconciles the double requirement of objectification and taking account of the practical logic bound by social agents. From the character both objective and subjective of social space, he analyzes how different institutions (firstly School) are doing that mental structures match the objective structures of society. By making acceptable reality and registering it in the body, these instances contribute to reproduce social divisions and participate in the work of domination. Gradually, Bourdieu develops a general theory about Power, which leads to a sociology of State. But he refuses any sociological fatalism. Because he perceived homologies between the sociologist and the artist facing the social order, each in their own way, he devoted two researches to Flaubert and Manet, seized in the same enterprise of aesthetic subversion he described as a 'symbolic revolution'. In many aspects, the sociology of Bourdieu opens ways of looking for an objectification of caregivers and their practices.

Influence of heat treatment and indenter tip material on depth sensing hardness tests at high temperatures of fusion relevant materials

International Nuclear Information System (INIS)

Bredl, Julian; Dany, Manuel; Albinski, Bartlomiej; Schneider, Hans-Christian; Kraft, Oliver

2015-01-01

Highlights: • Operation of a custom-made indentation device designed for test temperatures up to 650 °C and a remote handled operation in a Hot Cell. • Instrumented indentation and conventional hardness testing of unirradiated MANET II and EUROFER. • Comparison of diamond and sapphire as indenter tip materials. - Abstract: The instrumented indentation is a suitable method for testing of even small neutron-irradiated specimens. From the continuously recorded indentation depth and the indentation force, it is possible to deduce mechanical parameters of the tested material. In this paper, a brief description of the high temperature device is given and representative results are presented. In the study, unirradiated steels are investigated by instrumented indentation at temperatures up to 500 °C. It is shown that the hardness is highly depending on the testing-temperature and can be correlated to the results of conventional tensile testing experiments. A not negligible influence of the indenter tip material is observed. The results show the functionality of the high-temperature indentation device.

Influence of heat treatment and indenter tip material on depth sensing hardness tests at high temperatures of fusion relevant materials

Energy Technology Data Exchange (ETDEWEB)

Bredl, Julian, E-mail: julian.bredl@kit.edu; Dany, Manuel; Albinski, Bartlomiej; Schneider, Hans-Christian; Kraft, Oliver

2015-10-15

Highlights: • Operation of a custom-made indentation device designed for test temperatures up to 650 °C and a remote handled operation in a Hot Cell. • Instrumented indentation and conventional hardness testing of unirradiated MANET II and EUROFER. • Comparison of diamond and sapphire as indenter tip materials. - Abstract: The instrumented indentation is a suitable method for testing of even small neutron-irradiated specimens. From the continuously recorded indentation depth and the indentation force, it is possible to deduce mechanical parameters of the tested material. In this paper, a brief description of the high temperature device is given and representative results are presented. In the study, unirradiated steels are investigated by instrumented indentation at temperatures up to 500 °C. It is shown that the hardness is highly depending on the testing-temperature and can be correlated to the results of conventional tensile testing experiments. A not negligible influence of the indenter tip material is observed. The results show the functionality of the high-temperature indentation device.

A reliable, delay bounded and less complex communication protocol for multicluster FANETs

Directory of Open Access Journals (Sweden)

Wajiya Zafar

2017-02-01

Full Text Available Recently, Flying Ad-hoc Networks (FANETs, enabling ad-hoc networking between Unmanned Aerial Vehicles (UAVs is gaining importance in several military and civilian applications. The sensitivity of the applications requires adaptive; efficient; delay bounded and scalable communication network among UAVs for data transmission. Due to communication protocol complexity; rigidity; cost of commercial-off-the-shelf (COT components; limited radio bandwidth; high mobility and computational resources; maintaining the desired level of Quality of Service (QoS becomes a daunting task. For the first time in this research we propose multicluster FANETs for efficient network management; the proposed scheme considerably reduces communication cost and optimizes network performance as well as exploit low power; less complex and low cost IEEE 802.15.4 (MAC protocol for intercluster and intracluster communication. In this research both beacon enabled mode and beaconless modes have been investigated with Guaranteed Time Slots (GTS and virtual Time Division Multiple Access (TDMA respectively. The methodology plays a key role towards reserving bandwidth for latency critical applications; eliminate collisions and medium access delays. Moreover analysis ad-hoc routing protocols including two proactive (OLSR, DSDV and one reactive (AODV is also presented. The results shows that the proposed scheme guarantees high packet delivery ratios while maintaining acceptable levels of latency requirements comparable with more complex and dedicatedly designed protocols in literature.

Hydrogen permeation rate reduction by post-oxidation of aluminide coatings on DIN 1.4914 martensitic steel (MANET)

International Nuclear Information System (INIS)

Perujo, A.; Sample, T.

1996-01-01

In a previous work, it has been shown that lower aluminium content aluminide, having the same permeation rate reduction as the higher aluminium content, exhibited a lower hardness and greater ductility and therefore greater crack resistance than the higher aluminium content. In this work we combine this characteristic with a post-oxidation to obtain a further deuterium permeation reduction. The post-oxidation was performed in air at 1023 K for 15 h and at 1223 K for 10 h and 1 h. The maximum deuterium permeation rate reduction obtained is very moderate (maximum of a factor 500 for 1 h at 1223 K) as compared to that of the non-oxidised aluminide specimen (two orders of magnitude) and is constant in the temperature range studied (573-800 K). This method has the technological appeal of using air rather than the controlled environment used by other authors. (orig.)

Spectral imaging and archival data in analyzing the Madonna of the Rabbit painting by Manet and Titian

Czech Academy of Sciences Publication Activity Database

Striová, J.; Ruberto, C.; Barucci, M.; Blažek, Jan; Kunzelman, D.; Dal Fovo, A.; Pampaloni, E.; Fontana, R.

(2018) ISSN 1433-7851 Institutional support: RVO:67985556 Keywords : spectral mapping * image processing * visible near-infrared multispectral scanner Subject RIV: JC - Computer Hardware ; Software OBOR OECD: Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8) Impact factor: 11.994, year: 2016 http://library.utia.cas.cz/separaty/2018/ZOI/blazek-0489046.pdf

Power Aware Mobility Management of M2M for IoT Communications

Directory of Open Access Journals (Sweden)

Awais Ahmad

2015-01-01

Full Text Available Machine-to-Machine (M2M communications framework is evolving to sustain faster networks with the potential to connect millions of devices in the following years. M2M is one of the essential competences for implementing Internet of Things (IoT. Therefore, various organizations are now focusing on enhancing improvements into their standards to support M2M communications. Thus, Heterogeneous Mobile Ad Hoc Network (HetMANET can normally be considered appropriate for M2M challenges. These challenges incorporated when a mobile node (MN selects a target network in an energy efficient scanning for efficient handover. Therefore, to cope with these constraints, we proposed a vertical handover scheme for handover triggering and selection of an appropriate network. The proposed scheme is composed of two phases. Firstly, the MNs perform handover triggering based on the optimization of the Receive Signal Strength (RSS from an access point/base station (AP/BS. Secondly, the network selection process is performed by considering the cost and energy consumption of a particular application during handover. Moreover, if there are more networks available, then the MN selects the one provided with the highest quality of service (QoS. The decision regarding the selection of available networks is made on three metrics, that is, cost, energy, and data rate. Furthermore, the selection of an AP/BS of the selected network is made on five parameters: delay, jitter, Bit Error Rate (BER, communication cost, and response time. The numerical and experimental results are compared in the context of energy consumption by an MN, traffic management on an AP/BS, and QoS of the available networks. The proposed scheme efficiently optimizes the handoff related parameters, and it shows significant improvement in the existing models used for similar purpose.

Material Science Activities for Fusion Reactors in Kazakhstan

International Nuclear Information System (INIS)

Tazhibayeva, I.; Kenzhin, E.; Kulsartov, T.; Shestakov, V.; Chikhray, Y.; Azizov, E.; Filatov, O.; Chernov, V.M.

2007-01-01

Full text of publication follows: Paper contains results of fusion material testing national program and results of activities on creation of material testing spherical tokamak. Hydrogen isotope behavior (diffusion, permeation, and accumulation) in the components of the first wall and divertor was studied taking into account temperature, pressure, and reactor irradiation. There were carried out out-of-pile and in-pile (reactors IVG-IM, WWRK, RA) studies of beryllium of various grades (TV-56, TShG-56, DV-56, TGP-56, TIP-56), graphites (RG-T, MPG-8, FP 479, R 4340), molybdenum, tungsten, steels (Cr18Ni10Ti, Cr16Ni15, MANET, F82H), alloys V-(4-6)Cr-( 4-5)Ti, Cu+1%Cr+0.1%Zr, and double Be/Cu and triple Be/Cu/steel structures. Tritium permeability from eutectic Pb+17%Li through steels Cr18Ni10Ti, Cr16Ni15, MANET, and F82H were studied taking into account protective coating effects. The tritium production rate was experimentally assessed during in-pile and post-reactor experiments. There were carried out radiation tests of ceramic Li 2 TiO 3 (96% enrichment by Li-6) with in-situ registration of released tritium and following post-irradiation material tests of irradiated samples. Verification of computer codes for simulation of accidents related to LOCA in ITER reactor was carried out. Codes' verification was carried out for a mockup of first wall in a form of three-layer cylinder of beryllium, bronze (Cu-Cr-Zr) and stainless steel. At present Kazakhstan Tokamak for Material testing (tokamak KTM) is created in National Nuclear Center of Republic of Kazakhstan in cooperation with Russian Federation organizations (start-up is scheduled on 2008). Tokamak KTM allows for expansion and specification of the studies and tests of materials, protection options of first wall, receiving divertor tiles and divertor components, methods for load reduction at divertor, and various options of heat/power removal, fast evacuation of divertor volume and development of the techniques for

Traffic Agents for Improving QoS in Mixed Infrastructure and Ad Hoc Modes Wireless LAN

Directory of Open Access Journals (Sweden)

Yuan Hai-Feng

2006-01-01

Full Text Available As an important complement to infrastructured wireless networks, mobile ad hoc networks (MANET are more flexible in providing wireless access services, but more difficult in meeting different quality of service (QoS requirements for mobile customers. Both infrastructure and ad hoc network structures are supported in wireless local area networks (WLAN, which can offer high data-rate wireless multimedia services to the mobile stations (MSs in a limited geographical area. For those out-of-coverage MSs, how to effectively connect them to the access point (AP and provide QoS support is a challenging issue. By mixing the infrastructure and the ad hoc modes in WLAN, we propose in this paper a new coverage improvement scheme that can identify suitable idle MSs in good service zones as traffic agents (TAs to relay traffic from those out-of-coverage MSs to the AP. The service coverage area of WLAN is then expanded. The QoS requirements (e.g., bandwidth of those MSs are considered in the selection process of corresponding TAs. Mathematical analysis, verified by computer simulations, shows that the proposed TA scheme can effectively reduce blocking probability when traffic load is light.

Results of investigations regarding the physical and mechanical properties of the martensitic 9% Cr steel EUROFER '97; Ergebnisse von Charakterisierungsuntersuchungen zu physikalischen und mechanischen Eigenschaften des martensitischen 9% Cr-Stahles EUROFER '97

Energy Technology Data Exchange (ETDEWEB)

Schirra, M.; Falkenstein, A.; Graf, P.; Heger, S.; Kempe, H.; Lindau, R.; Zimmermann, H.

2002-04-01

Following the history of the development activities from conventional martensitic 12% Cr steel, MANET and OPTIFER up to low-activated EUROFER (RAFM steel), the results obtained from experiments on rods of 100 mm diameter and plates of 14 mm shall be presented for a basic characterization. The physical and mechanical properties shall be compared with those of OPTIFER-1W and the F82H-mod 2% W steel. To determine the conversion behavior, a continuous cct diagram was plotted. Hardening experiments in the temperature range of 850 - 1120 C illustrated the range of maximum hardness as well as grain size development. The notch impact behavior was described for various heat treatments and sample types at test temperatures ranging from +60 to -100 C. Tensile strengths were determined for various heat treatments at temperatures ranging from room temperature to 700 C. Aging due to a long-term heat treatment was investigated by means of stabilization annealing experiments. Creep rupture strength and creeping were investigated in the temperature range of 450 - 650 C. So far, a duration of up to about 15 000 h has been covered by the experiments. (orig.)

Studi Komparatif Lukisan Perempuan Perupa dengan Pria Perupa Impresionis dalam Tema Kehidupan Keseharian

Directory of Open Access Journals (Sweden)

Ira Adriati Winarno

2008-03-01

Full Text Available Impressionism is an art movement that firstly established in France in the middle of 19th century. Claude Monet, Èdouard Manet, Pierre-Auguste Renoir, and Edgar Degas are famous male impressionist artists that were known by many, yet there are famous female impressionist artists such as Berthe Morisot, Mary Cassatt, Eva Gonzales, and Marie Bracquemond that deserve to be known as well. The presented paper discusses the aesthetics value and meanings of paintings of these female impressionist artists, through the perspective of art criticism, historical method, and women studies. Object of analysis are paintings that depicting domestic life made by mentioned artists above. Results show that the depicted domestic life in those paintings presented a unique gaze of a woman, as shown in the representation of body language to express the relationship between mother and children. Thus, female impressionist paintings emphasize more on the activities and aspiration of women than the beauty of their bodies. The painted theme shows that the artists express gender equality and/or independent (or self-supporting women, which are presented in an equal aesthetic quality compared to those of male impressionist artists.

PROTOCOLS FOR INCREASING THE LIFETIME OF NODES OF AD HOC WIRELESS NETWORKS

Directory of Open Access Journals (Sweden)

B.Malarkodi

2010-03-01

Full Text Available Power consumption of nodes in ad hoc networks is a critical issue as they predominantly operate on batteries. In order to improve the lifetime of an ad hoc network, all the nodes must be utilized evenly and the power required for connections must be minimized. Energy management deals with the process of managing energy resources by means of controlling the battery discharge, adjusting the transmission power and scheduling of power sources so as to increase the lifetime of the nodes of an ad hoc wireless network. In this paper, two protocols are proposed to improve the lifetime of the nodes. The first protocol assumes smart battery packages with L cells and uses dynamic programming (DP to optimally select the set of cells used to satisfy a request for power. The second one proposes a MAC layer protocol denoted as Power Aware medium Access Control (PAMAC protocol which enables the network layer to select a route with minimum total power requirement among the possible routes between a source and a destination provided all nodes in the routes have battery capacity above a threshold. The life time of the nodes using the DP based scheduling policy is found through simulation and compared with that obtained using the techniques reported in the literature. It is found that DP based policy increases the lifetime of the mobile nodes by a factor of 1.15 to 1.8. The life expectancy, the average power consumption and throughput of the network using PAMAC protocol are computed through simulation and compared with that of the other MAC layer protocols 802.11, MACA, and CSMA. Besides this, the life expectancy and average power consumption of the network for different values of threshold are also compared. From the simulation results, it is observed that PAMAC consumes the least power and provides the longest lifetime among the various MAC Layer protocols. Moreover, using PAMAC as the MAC layer protocol, the performance obtained using different routing layer

Analyzing the effect of routing protocols on media access control protocols in radio networks

Energy Technology Data Exchange (ETDEWEB)

Barrett, C. L. (Christopher L.); Drozda, M. (Martin); Marathe, A. (Achla); Marathe, M. V. (Madhav V.)

2002-01-01

We study the effect of routing protocols on the performance of media access control (MAC) protocols in wireless radio networks. Three well known MAC protocols: 802.11, CSMA, and MACA are considered. Similarly three recently proposed routing protocols: AODV, DSR and LAR scheme 1 are considered. The experimental analysis was carried out using GloMoSim: a tool for simulating wireless networks. The main focus of our experiments was to study how the routing protocols affect the performance of the MAC protocols when the underlying network and traffic parameters are varied. The performance of the protocols was measured w.r.t. five important parameters: (i) number of received packets, (ii) average latency of each packet, (iii) throughput (iv) long term fairness and (v) number of control packets at the MAC layer level. Our results show that combinations of routing and MAC protocols yield varying performance under varying network topology and traffic situations. The result has an important implication; no combination of routing protocol and MAC protocol is the best over all situations. Also, the performance analysis of protocols at a given level in the protocol stack needs to be studied not locally in isolation but as a part of the complete protocol stack. A novel aspect of our work is the use of statistical technique, ANOVA (Analysis of Variance) to characterize the effect of routing protocols on MAC protocols. This technique is of independent interest and can be utilized in several other simulation and empirical studies.

基于移动-能量代价函数的无线自组织网络路由策略研究%Research on the Routing Algorithm in MANETsBased on the Energy Cost Function

Institute of Scientific and Technical Information of China (English)

刘半藤; 周莹; 陈友荣; 王章权

2017-01-01

能量均衡技术一直是无线自组织网络的热点研究领域.在深入研究网络信息传输特性的基础上,提出了一种基于移动-能量代价函数的无线自组织网络路由策略,并用于网络信息传输.首先,本文考虑节点连通性、能量均衡性,提出了一种节点移动策略;然后,以传输路径节点集合中的瓶颈节点剩余能量、传输链路数量作为准则,建立以网络节点为对象的能量代价函数.基于移动-能量代价函数的路由策略从链路层的决策转移到节点层的决策.最后,采用MATLAB数值仿真该路由策略的性能,结果显示:本文提出的移动-能量代价函数的路由策略既保持了原有路由优化的精度,延迟网络瓶颈节点能量下降速度,提高网络生存时间.%The energy balance technology is a hot research field of the wireless selforganizing network.After the further study of the network information transmission characteristics,a kind of wireless selforganized network routing strategy used for network information transmission is proposed based on mobile-energy cost function.At first,considering the node connectivity and energy balance,a node mobile strategy is carried out;then a energy cost function is designed With residual energy of transmission path bottleneck nodes and transmission link number as criterion,and the routing strategy is determined in node layer instead of link layer;at last,the numerical simulation is performed on MATLAB,the result shows the routing strategy proposed keep the original optimal routing precision,delay the network bottleneck node energy falling speed and improve the network survival time.

Cuestión de tiempo: Michael Fried y el tiempo del arte moderno A matter of time: Michael Fried and modernist art the time of modernist art

Directory of Open Access Journals (Sweden)

David Díaz Soto

2011-07-01

Full Text Available En el siglo XIX, autores fundacionales del formalismo, como Fiedler o Hildebrand, contrapusieron estrictamente las artes plásticas, «puramente visuales», a las artes verbales del discurso, proscribiéndoles la narración y disociándolas de la temporalidad: se trata del «principio de exclusión del tiempo», vinculado al formalismo. Más tarde, el crítico «modernista» de arte Clement Greenberg planteó la instantaneidad, en tanto que opuesta a la duración, como modalidad ideal de la experiencia artística. Pero el historiador y crítico de arte Michael Fried, en sus textos de los años 60 sobre arte abstracto, se distancia de Greenberg, desarrollando un discurso sobre la temporalidad en las artes plásticas, con nociones como «tiempo visual»; y en sus posteriores textos historiográficos investiga las modalidades temporales de la representación pictórica. La aparente paradoja entre la crítica de Fried a la hipóstasis «literalista» de la duración en las tardovanguardias y el papel crucial que concede a Manet y a la instantaneidad en el origen del arte moderno, la resolveremos atendiendo a su reivindicación de la temporalidad durativa de «lo cotidiano». Así cabe comprender la concepción de la modalidad temporal característica de la modernidad y del arte moderno, a la que apunta su noción teórica de presentness.In the nineteenth century, seminal authors of Formalism, like Fiedler or Hildebrand, strictly compared the «purely visual» plastic arts to the discursive arts of verbal language, ruling out narrativity from plastic arts, which they dissociated from temporality - the formalist «principle of exclusion of time». Later on, «modernist» art critic Clement Greenberg claimed that instantaneousness, as opposed to duration, was the ideal modality for artistic experience. Art critic and historian Michael Fried did not share Greenberg's position, but developed instead a discourse about time in plastic arts. In his early

Alloying of aluminum and its influence on the properties of aluminide coatings: oxidation behavior and the chemical stability in Pb-17Li

International Nuclear Information System (INIS)

Glasbrenner, H.; Peric, Z.; Borgstedt, H.U.

1996-01-01

Electrical insulation of the structural material is necessary to reduce the MHD pressure drop in a self-cooled liquid metal blanket. This coating has to be compatible with liquid Pb-17Li up to 450 C. Specimens with different types of coatings were exposed to static Pb-17Li for 1200 h at 450 C in order to study their compatibility. Iron and a ferritic steel were coated with an aluminide layer by means of an aluminizing process. Iron metal plate was hot dip aluminized at Thyssen, Germany. The preheated sheet was coated for this purpose by exposing for a few seconds to a melt of Al with 10 wt% Si. The ferritic steel, MANET, was immersed into a melt of the same composition. In this case, cold specimens were dipped into the melt at 700 C for up to 10 min. The formation of the required oxide scale on top of the aluminide layer was performed by using two different methods: high temperature oxidation in air and anodic oxidation at room temperature. All the exposed specimens were examined before and after the corrosion experiments. The analytical method used is EDX measurements on the cut of the specimens and metallographical examinations. (orig.)

Dynamic fair node spectrum allocation for ad hoc networks using random matrices

Science.gov (United States)

Rahmes, Mark; Lemieux, George; Chester, Dave; Sonnenberg, Jerry

2015-05-01

Dynamic Spectrum Access (DSA) is widely seen as a solution to the problem of limited spectrum, because of its ability to adapt the operating frequency of a radio. Mobile Ad Hoc Networks (MANETs) can extend high-capacity mobile communications over large areas where fixed and tethered-mobile systems are not available. In one use case with high potential impact, cognitive radio employs spectrum sensing to facilitate the identification of allocated frequencies not currently accessed by their primary users. Primary users own the rights to radiate at a specific frequency and geographic location, while secondary users opportunistically attempt to radiate at a specific frequency when the primary user is not using it. We populate a spatial radio environment map (REM) database with known information that can be leveraged in an ad hoc network to facilitate fair path use of the DSA-discovered links. Utilization of high-resolution geospatial data layers in RF propagation analysis is directly applicable. Random matrix theory (RMT) is useful in simulating network layer usage in nodes by a Wishart adjacency matrix. We use the Dijkstra algorithm for discovering ad hoc network node connection patterns. We present a method for analysts to dynamically allocate node-node path and link resources using fair division. User allocation of limited resources as a function of time must be dynamic and based on system fairness policies. The context of fair means that first available request for an asset is not envied as long as it is not yet allocated or tasked in order to prevent cycling of the system. This solution may also save money by offering a Pareto efficient repeatable process. We use a water fill queue algorithm to include Shapley value marginal contributions for allocation.

Survey on Monitoring and Quality Controlling of the Mobile Biosignal Delivery.

Science.gov (United States)

Pawar, Pravin A; Edla, Damodar R; Edoh, Thierry; Shinde, Vijay; van Beijnum, Bert-Jan

2017-10-31

A Mobile Patient Monitoring System (MPMS) acquires patient's biosignals and transmits them using wireless network connection to the decision-making module or healthcare professional for the assessment of patient's condition. A variety of wireless network technologies such as wireless personal area networks (e.g., Bluetooth), mobile ad-hoc networks (MANET), and infrastructure-based networks (e.g., WLAN and cellular networks) are in practice for biosignals delivery. The wireless network quality-of-service (QoS) requirements of biosignals delivery are mainly specified in terms of required bandwidth, acceptable delay, and tolerable error rate. An important research challenge in the MPMS is how to satisfy QoS requirements of biosignals delivery in the environment characterized by patient mobility, deployment of multiple wireless network technologies, and variable QoS characteristics of the wireless networks. QoS requirements are mainly application specific, while available QoS is largely dependent on QoS provided by wireless network in use. QoS provisioning refers to providing support for improving QoS experience of networked applications. In resource poor conditions, application adaptation may also be required to make maximum use of available wireless network QoS. This survey paper presents a survey of recent developments in the area of QoS provisioning for MPMS. In particular, our contributions are as follows: (1) overview of wireless networks and network QoS requirements of biosignals delivery; (2) survey of wireless networks' QoS performance evaluation for the transmission of biosignals; and (3) survey of QoS provisioning mechanisms for biosignals delivery in MPMS. We also propose integrating end-to-end QoS monitoring and QoS provisioning strategies in a mobile patient monitoring system infrastructure to support optimal delivery of biosignals to the healthcare professionals.

A Unified NET-MAC-PHY Cross-layer Framework for Performance Evaluation of Multi-hop Ad hoc WLANs

Directory of Open Access Journals (Sweden)

Rachid El-Azouzi

2014-09-01

Full Text Available Most of the existing works have been evaluated the performance of 802.11 multihop networks by considering the MAC layer or network layer separately. Knowing the nature of the multi-hop ad hoc networks, many factors in different layers are crucial for study the performance of MANET. In this paper we present a new analytic model for evaluating average end-to-end throughput in IEEE 802.11e multihop wireless networks. In particular, we investigate an intricate interaction among PHY, MAC and Network layers. For instance, we incorporate carrier sense threshold, transmission power, contention window size, retransmissions retry limit, multi rates, routing protocols and network topology together. We build a general cross-layered framework to represent multi-hop ad hoc networks with asymmetric topology and asymmetric traffic. We develop an analytical model to predict throughput of each connection as well as stability of forwarding queues at intermediate nodes in saturated networks. To the best of our knowledge, it seems that our work is the first wherein general topology and asymmetric parameters setup are considered in PHY/MAC/Network layers. Performance of such a system is also evaluated through simulation. We show that performance measures of the MAC layer are affected by the traffic intensity of flows to be forwarded. More precisely, attempt rate and collision probability are dependent on traffic flows, topology and routing.

Promoting Wired Links in Wireless Mesh Networks: An Efficient Engineering Solution

Science.gov (United States)

Barekatain, Behrang; Raahemifar, Kaamran; Ariza Quintana, Alfonso; Triviño Cabrera, Alicia

2015-01-01

Wireless Mesh Networks (WMNs) cannot completely guarantee good performance of traffic sources such as video streaming. To improve the network performance, this study proposes an efficient engineering solution named Wireless-to-Ethernet-Mesh-Portal-Passageway (WEMPP) that allows effective use of wired communication in WMNs. WEMPP permits transmitting data through wired and stable paths even when the destination is in the same network as the source (Intra-traffic). Tested with four popular routing protocols (Optimized Link State Routing or OLSR as a proactive protocol, Dynamic MANET On-demand or DYMO as a reactive protocol, DYMO with spanning tree ability and HWMP), WEMPP considerably decreases the end-to-end delay, jitter, contentions and interferences on nodes, even when the network size or density varies. WEMPP is also cost-effective and increases the network throughput. Moreover, in contrast to solutions proposed by previous studies, WEMPP is easily implemented by modifying the firmware of the actual Ethernet hardware without altering the routing protocols and/or the functionality of the IP/MAC/Upper layers. In fact, there is no need for modifying the functionalities of other mesh components in order to work with WEMPPs. The results of this study show that WEMPP significantly increases the performance of all routing protocols, thus leading to better video quality on nodes. PMID:25793516

Synthesis and Biochemical effects of magnetite nanoparticle by surfactant-free electrochemical method in an aqueous system:the current density effect

Directory of Open Access Journals (Sweden)

Mousa Aliahmad

2016-07-01

Full Text Available Obejective(s: In this research, magnetite nanoparticles with an average size of 23-36 nm were successfully synthesized via surfactant-free electrochemical method using iron as the anode and water as the electrolyte in a closed aqueous system in the presence of NaOH at room temperature. Methods: The effect of the current density on product formation and particle size was investigated. Particle size was controlled by adjusting the current density. It was found that particle size decreases by decreasing the current density. In addition, the effect of current density  on the structural and optical properties of nanostructures were studied by X-ray diffraction, Field emission scanning electron microscopy, Fourier transformed infrared, and vibrating sample magnetometer techniques.  Results: The results obtained from the magnetization property study of samples at room temperature showed coactivity and saturation manetization of 0-100 Oe and 27.2- 40.5 emu. g-1, respectively. Finally, the results of biological activity study of nanoparticles on liver and kidney function in male wistar rats demonstrated that oral administration of NPs caused significant alterations to the levels of aspartate transaminase, alanine transaminase, and alkaline phosphatase in serum. Conclusions: No significant changes were detected in the groups treated with 10 and 100 ppm/ day nanostructure (P>0.05. There was a significant increase in the serum level of creatinine and blood urea nitrogen level (p

Nuclear Fusion Project. Semi-annual report of the Association KfK/EURATOM

International Nuclear Information System (INIS)

Kast, G.

1989-04-01

Report on technology tasks: Blanket design studies; development of computational tools for neutronics; corrosion and fatigue of structural materials in flowing Pb-17Li; tritium extraction from liquid Pb-17Li by the use of solid getters; ceramic breeder materials; high field composite conductors; superconducting poloidal field coil development; design and construction of a poloidal field coil for TORE SUPRA as NET-prototype coil; structural materials fatigue characterization at 4 K; low electrical conductivity structural development; MANET 1; pre- and post-irradiation fatigue properties of 1.4914 martensitic steel; in-pile creep-fatigue testing of type 316 and 1.4914 steel; ceramics for first-wall protection and for RF windows; fatigue under dual beam irradiation; low activation ferritic-martensitic steels; plasma facing components; procedures and tools for structural design evaluation; remote maintenance; mechanical component assembly; handling equipment for in-vessel components; safety aspects of the cryosystem and of superconducting magnets; safety guidelines for the design of NET; generic environmental impact assessment for a fusion facility; large components for plasma exhaust pumping; optimization of cryogenic vacuum pumping of He; solid particle separators for plasma exhaust; plasma exhaust purification; adsorption of DT on heated metal beds other than U; catalyst development for the exhaust purification process; ECRH power sources; vacuum and exhaust performance of NET; NET TF pancake tests; CAD DATA exchange between NET and KfK; catalytic plasma exhaust gas clean-up facility for NET; NET blanket handling device; electrical connectors for remote handling. (orig./HP)

ESTADO DEL ARTE EN REDES VANET Y CADENAS DE MARKOV

Directory of Open Access Journals (Sweden)

Jorge Blanco

2012-02-01

Full Text Available El  presente  artículo  resume  el  estado  del  arte  de  las redes  VANET  como  una  extensión  de  las  redes MANET,  por  tener  características  particulares  en cuanto a la forma de construir topologías que cambian   dinámicamente  en  el  tiempo,  en  tal  sentido,  se proponen los argumento para que en futuros trabajos de  investigación,  se  haga  un  análisis  no  desde  el punto  vista  de  simulación,  sino  desde  el  punto  de vista  matemático  para  que  se  desarrolle  a  través  de cadenas de Markov, ya que la construcción de redes VANET corresponde o puede verse como  un proceso estocástico    discreto,    que    puede   ser   analizado matemáticamente por medio de dichas cadenas,  con el fin de garantizar una  entrega confiable de paquetes de  información  entre  vehículos  los  cuales  están entrando  y  saliendo  constantemente  dentro  de  la topología de red.

Fuzzy knowledge bases integration based on ontology

OpenAIRE

Ternovoy, Maksym; Shtogrina, Olena

2012-01-01

the paper describes the approach for fuzzy knowledge bases integration with the usage of ontology. This approach is based on metadata-base usage for integration of different knowledge bases with common ontology. The design process of metadata-base is described.

Foundation: Transforming data bases into knowledge bases

Science.gov (United States)

Purves, R. B.; Carnes, James R.; Cutts, Dannie E.

1987-01-01

One approach to transforming information stored in relational data bases into knowledge based representations and back again is described. This system, called Foundation, allows knowledge bases to take advantage of vast amounts of pre-existing data. A benefit of this approach is inspection, and even population, of data bases through an intelligent knowledge-based front-end.

Case-based reasoning: The marriage of knowledge base and data base

Science.gov (United States)

Pulaski, Kirt; Casadaban, Cyprian

1988-01-01

The coupling of data and knowledge has a synergistic effect when building an intelligent data base. The goal is to integrate the data and knowledge almost to the point of indistinguishability, permitting them to be used interchangeably. Examples given in this paper suggest that Case-Based Reasoning is a more integrated way to link data and knowledge than pure rule-based reasoning.

Evaluation of Data Transfer Performance Between Moving Sender and Receiver in Mobile Communication Networks for Heterogeneous Service Support

Directory of Open Access Journals (Sweden)

Dalė Dzemydienė

2011-12-01

Full Text Available Vehicular communication networks are acquiring more and more commercial relevance because of recent advances in inter-vehicular communications via the DSRC/WAVE standard, which stimulates a brand new family of visionary services for vehicles, from road safety to entertainment and multimedia applications. After deep analysis of the literature it was decided to investigate evaluation of data transfer performance between moving sender and receiver in mobile communication network for heterogeneous service support. After careful analysis of the simulation tools the NCTUns 6.0 software package was chosen for planned investigations. The results illustrate that the longest communication can be maintained at the maximum number of vehicles participating on the network, but the quality of communication is inversely proportional to the number of vehicles. On this changing topology network when growing number of nodes (vehicles increases flooding of network with the data packages and it determines many collisions. The number of rejected packages increases directly in proportion to the number of vehicles. When the number of nodes (vehicle increases—it is increasing the number of the received same packages which are received from different nodes in the recipient node. On the sender node, the packages are rejected because the collisions occur due to improperly functioning access channel allocation mechanisms. It can be concluded that the routing protocols created for a normal MANET networks is useless in a fast-changing topology large-scale vehicle communication network. To provide heterogeneous services new routing protocols and channel access methods are needed, specifically for vehicle communication networks.

Evaluation of Data Transfer Performance Between Moving Sender and Receiver in Mobile Communication Networks for Heterogeneous Service Support

Directory of Open Access Journals (Sweden)

Dalė Dzemydienė

2013-08-01

Full Text Available Vehicular communication networks are acquiring more and more commercial relevance because of recent advances in inter-vehicular communications via the DSRC/WAVE standard, which stimulates a brand new family of visionary services for vehicles, from road safety to entertainment and multimedia applications. After deep analysis of the literature it was decided to investigate evaluation of data transfer performance between moving sender and receiver in mobile communication network for heterogeneous service support. After careful analysis of the simulation tools the NCTUns 6.0 software package was chosen for planned investigations. The results illustrate that the longest communication can be maintained at the maximum number of vehicles participating on the network, but the quality of communication is inversely proportional to the number of vehicles. On this changing topology network when growing number of nodes (vehicles increases flooding of network with the data packages and it determines many collisions. The number of rejected packages increases directly in proportion to the number of vehicles. When the number of nodes (vehicle increases—it is increasing the number of the received same packages which are received from different nodes in the recipient node. On the sender node, the packages are rejected because the collisions occur due to improperly functioning access channel allocation mechanisms. It can be concluded that the routing protocols created for a normal MANET networks is useless in a fast-changing topology large-scale vehicle communication network. To provide heterogeneous services new routing protocols and channel access methods are needed, specifically for vehicle communication networks.

From oil-based mud to water-based mud

International Nuclear Information System (INIS)

Christiansen, C.

1991-01-01

Maersk Olie og Gas AS has used low toxic oil-based muds extensively since 1982 for drilling development wells and later in the development of horizontal well drilling techniques. However, in view of the strong drive towards a reduction in the amount of oil discharged to the North Sea from the oil industry, Maersk Olie og Gas AS initiated trials with new or improved types of water-based mud, first in deviated wells (1989) and then in horizontal wells (1990). The paper reviews Maersk Olie og Gas As experience with oil-based mud since the drilling of the first horizontal well in 1987, specifically with respect to cuttings washing equipment, oil retention on cuttings, and the procedure for monitoring of this parameter. It describes the circumstances leading to the decision to revert to water-based mud systems. Finally, it reviews the experience gained so far with the new improved types of water-based mud systems, mainly glycol and KCl/polymer mud systems. Comparison of operational data, such as rate of penetration, torque and drag, etc., is made between wells drilled with oil-based mud and water-based mud. The trials with the new improved types of water-based mud systems have been positive, i.e. horizontal wells can be drilled successfully with water-based mud. As a result, Maersk Olie og and Gas AS has decided to discontinue the use of low toxic oil-based muds in the Danish sector of the North Sea

Computer-based multi-channel analyzer based on internet

International Nuclear Information System (INIS)

Zhou Xinzhi; Ning Jiaoxian

2001-01-01

Combined the technology of Internet with computer-based multi-channel analyzer, a new kind of computer-based multi-channel analyzer system which is based on browser is presented. Its framework and principle as well as its implementation are discussed

Combining Host-based and network-based intrusion detection system

African Journals Online (AJOL)

These attacks were simulated using hping. The proposed system is implemented in Java. The results show that the proposed system is able to detect attacks both from within (host-based) and outside sources (network-based). Key Words: Intrusion Detection System (IDS), Host-based, Network-based, Signature, Security log.

NMR studies concerning base-base interactions in oligonucleotides

International Nuclear Information System (INIS)

Hoogen, Y.T. van den.

1988-01-01

Two main subjects are treated in the present thesis. The firsst part principally deals with the base-base interactions in single-stranded oligoribonucleotides. The second part presents NMR and model-building studies of DNA and RNA duplexes containing an unpaired base. (author). 242 refs.; 26 figs.; 24 tabs

XML-Based SHINE Knowledge Base Interchange Language

Science.gov (United States)

James, Mark; Mackey, Ryan; Tikidjian, Raffi

2008-01-01

The SHINE Knowledge Base Interchange Language software has been designed to more efficiently send new knowledge bases to spacecraft that have been embedded with the Spacecraft Health Inference Engine (SHINE) tool. The intention of the behavioral model is to capture most of the information generally associated with a spacecraft functional model, while specifically addressing the needs of execution within SHINE and Livingstone. As such, it has some constructs that are based on one or the other.

Communication Base Station Log Analysis Based on Hierarchical Clustering

Directory of Open Access Journals (Sweden)

Zhang Shao-Hua

2017-01-01

Full Text Available Communication base stations generate massive data every day, these base station logs play an important value in mining of the business circles. This paper use data mining technology and hierarchical clustering algorithm to group the scope of business circle for the base station by recording the data of these base stations.Through analyzing the data of different business circle based on feature extraction and comparing different business circle category characteristics, which can choose a suitable area for operators of commercial marketing.

Value-based metrics and Internet-based enterprises

Science.gov (United States)

Gupta, Krishan M.

2001-10-01

Within the last few years, a host of value-based metrics like EVA, MVA, TBR, CFORI, and TSR have evolved. This paper attempts to analyze the validity and applicability of EVA and Balanced Scorecard for Internet based organizations. Despite the collapse of the dot-com model, the firms engaged in e- commerce continue to struggle to find new ways to account for customer-base, technology, employees, knowledge, etc, as part of the value of the firm. While some metrics, like the Balance Scorecard are geared towards internal use, others like EVA are for external use. Value-based metrics are used for performing internal audits as well as comparing firms against one another; and can also be effectively utilized by individuals outside the firm looking to determine if the firm is creating value for its stakeholders.

Integrated Case Based and Rule Based Reasoning for Decision Support

OpenAIRE

Eshete, Azeb Bekele

2009-01-01

This project is a continuation of my specialization project which was focused on studying theoretical concepts related to case based reasoning method, rule based reasoning method and integration of them. The integration of rule-based and case-based reasoning methods has shown a substantial improvement with regards to performance over the individual methods. Verdande Technology As wants to try integrating the rule based reasoning method with an existing case based system. This project focu...

Knowledge base verification based on enhanced colored petri net

Energy Technology Data Exchange (ETDEWEB)

Kim, Jong Hyun; Seong, Poong Hyun [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

1998-12-31

Verification is a process aimed at demonstrating whether a system meets it`s specified requirements. As expert systems are used in various applications, the knowledge base verification of systems takes an important position. The conventional Petri net approach that has been studied recently in order to verify the knowledge base is found that it is inadequate to verify the knowledge base of large and complex system, such as alarm processing system of nuclear power plant. Thus, we propose an improved method that models the knowledge base as enhanced colored Petri net. In this study, we analyze the reachability and the error characteristics of the knowledge base and apply the method to verification of simple knowledge base. 8 refs., 4 figs. (Author)

Knowledge base verification based on enhanced colored petri net

Energy Technology Data Exchange (ETDEWEB)

Kim, Jong Hyun; Seong, Poong Hyun [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

1997-12-31

Verification is a process aimed at demonstrating whether a system meets it`s specified requirements. As expert systems are used in various applications, the knowledge base verification of systems takes an important position. The conventional Petri net approach that has been studied recently in order to verify the knowledge base is found that it is inadequate to verify the knowledge base of large and complex system, such as alarm processing system of nuclear power plant. Thus, we propose an improved method that models the knowledge base as enhanced colored Petri net. In this study, we analyze the reachability and the error characteristics of the knowledge base and apply the method to verification of simple knowledge base. 8 refs., 4 figs. (Author)

Computer-based and web-based radiation safety training

Energy Technology Data Exchange (ETDEWEB)

Owen, C., LLNL

1998-03-01

The traditional approach to delivering radiation safety training has been to provide a stand-up lecture of the topic, with the possible aid of video, and to repeat the same material periodically. New approaches to meeting training requirements are needed to address the advent of flexible work hours and telecommuting, and to better accommodate individuals learning at their own pace. Computer- based and web-based radiation safety training can provide this alternative. Computer-based and web- based training is an interactive form of learning that the student controls, resulting in enhanced and focused learning at a time most often chosen by the student.

Content-Based Image Retrial Based on Hadoop

Directory of Open Access Journals (Sweden)

DongSheng Yin

2013-01-01

Full Text Available Generally, time complexity of algorithms for content-based image retrial is extremely high. In order to retrieve images on large-scale databases efficiently, a new way for retrieving based on Hadoop distributed framework is proposed. Firstly, a database of images features is built by using Speeded Up Robust Features algorithm and Locality-Sensitive Hashing and then perform the search on Hadoop platform in a parallel way specially designed. Considerable experimental results show that it is able to retrieve images based on content on large-scale cluster and image sets effectively.

Home-based versus centre-based cardiac rehabilitation.

Science.gov (United States)

Taylor, Rod S; Dalal, Hayes; Jolly, Kate; Moxham, Tiffany; Zawada, Anna

2010-01-20

The burden of cardiovascular disease world-wide is one of great concern to patients and health care agencies alike. Traditionally centre-based cardiac rehabilitation (CR) programmes are offered to individuals after cardiac events to aid recovery and prevent further cardiac illness. Home-based cardiac rehabilitation programmes have been introduced in an attempt to widen access and participation. To determine the effectiveness of home-based cardiac rehabilitation programmes compared with supervised centre-based cardiac rehabilitation on mortality and morbidity, health-related quality of life and modifiable cardiac risk factors in patients with coronary heart disease. We updated the search of a previous review by searching the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2007, Issue 4), MEDLINE, EMBASE and CINAHL from 2001 to January 2008. We checked reference lists and sought advice from experts. No language restrictions were applied. Randomised controlled trials (RCTs) that compared centre-based cardiac rehabilitation (e.g. hospital, gymnasium, sports centre) with home-based programmes, in adults with myocardial infarction, angina, heart failure or who had undergone revascularisation. Studies were selected independently by two reviewers, and data extracted by a single reviewer and checked by a second one. Authors were contacted where possible to obtain missing information. Twelve studies (1,938 participants) met the inclusion criteria. The majority of studies recruited a lower risk patient following an acute myocardial infarction (MI) and revascularisation. There was no difference in outcomes of home- versus centre-based cardiac rehabilitation in mortality risk ratio (RR) was1.31 (95% confidence interval (C) 0.65 to 2.66), cardiac events, exercise capacity standardised mean difference (SMD) -0.11 (95% CI -0.35 to 0.13), as well as in modifiable risk factors (systolic blood pressure; diastolic blood pressure; total cholesterol

14 CFR 119.47 - Maintaining a principal base of operations, main operations base, and main maintenance base...

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Maintaining a principal base of operations, main operations base, and main maintenance base; change of address. 119.47 Section 119.47 Aeronautics... Under Part 121 or Part 135 of This Chapter § 119.47 Maintaining a principal base of operations, main...

Model-Based Requirements Management in Gear Systems Design Based On Graph-Based Design Languages

Directory of Open Access Journals (Sweden)

Kevin Holder

2017-10-01

Full Text Available For several decades, a wide-spread consensus concerning the enormous importance of an in-depth clarification of the specifications of a product has been observed. A weak clarification of specifications is repeatedly listed as a main cause for the failure of product development projects. Requirements, which can be defined as the purpose, goals, constraints, and criteria associated with a product development project, play a central role in the clarification of specifications. The collection of activities which ensure that requirements are identified, documented, maintained, communicated, and traced throughout the life cycle of a system, product, or service can be referred to as “requirements engineering”. These activities can be supported by a collection and combination of strategies, methods, and tools which are appropriate for the clarification of specifications. Numerous publications describe the strategy and the components of requirements management. Furthermore, recent research investigates its industrial application. Simultaneously, promising developments of graph-based design languages for a holistic digital representation of the product life cycle are presented. Current developments realize graph-based languages by the diagrams of the Unified Modelling Language (UML, and allow the automatic generation and evaluation of multiple product variants. The research presented in this paper seeks to present a method in order to combine the advantages of a conscious requirements management process and graph-based design languages. Consequently, the main objective of this paper is the investigation of a model-based integration of requirements in a product development process by means of graph-based design languages. The research method is based on an in-depth analysis of an exemplary industrial product development, a gear system for so-called “Electrical Multiple Units” (EMU. Important requirements were abstracted from a gear system

Solid Base Catalysis

CERN Document Server

Ono, Yoshio

2011-01-01

The importance of solid base catalysts has come to be recognized for their environmentally benign qualities, and much significant progress has been made over the past two decades in catalytic materials and solid base-catalyzed reactions. The book is focused on the solid base. Because of the advantages over liquid bases, the use of solid base catalysts in organic synthesis is expanding. Solid bases are easier to dispose than liquid bases, separation and recovery of products, catalysts and solvents are less difficult, and they are non-corrosive. Furthermore, base-catalyzed reactions can be performed without using solvents and even in the gas phase, opening up more possibilities for discovering novel reaction systems. Using numerous examples, the present volume describes the remarkable role solid base catalysis can play, given the ever increasing worldwide importance of "green" chemistry. The reader will obtain an overall view of solid base catalysis and gain insight into the versatility of the reactions to whic...

Evidence-based monitoring and evaluation of the faith-based ...

African Journals Online (AJOL)

Background: The Islamic Medical Association of Uganda, has been implementing the faith-based approach to HIV prevention without baseline data on expected positive outcomes. Objectives: To establish evidence-based baseline data on expected positive outcomes of the faith-based approach to HIV prevention. Methods: ...

Covariance-Based Measurement Selection Criterion for Gaussian-Based Algorithms

Directory of Open Access Journals (Sweden)

Fernando A. Auat Cheein

2013-01-01

Full Text Available Process modeling by means of Gaussian-based algorithms often suffers from redundant information which usually increases the estimation computational complexity without significantly improving the estimation performance. In this article, a non-arbitrary measurement selection criterion for Gaussian-based algorithms is proposed. The measurement selection criterion is based on the determination of the most significant measurement from both an estimation convergence perspective and the covariance matrix associated with the measurement. The selection criterion is independent from the nature of the measured variable. This criterion is used in conjunction with three Gaussian-based algorithms: the EIF (Extended Information Filter, the EKF (Extended Kalman Filter and the UKF (Unscented Kalman Filter. Nevertheless, the measurement selection criterion shown herein can also be applied to other Gaussian-based algorithms. Although this work is focused on environment modeling, the results shown herein can be applied to other Gaussian-based algorithm implementations. Mathematical descriptions and implementation results that validate the proposal are also included in this work.

Model-Based Learning Environment Based on The Concept IPS School-Based Management

Directory of Open Access Journals (Sweden)

Hamid Darmadi

2017-03-01

Full Text Available The results showed: (1 learning model IPS-oriented environment can grow and not you love the cultural values of the area as a basis for the development of national culture, (2 community participation, and the role of government in implementing learning model of IPS-based environment provides a positive impact for the improvement of management school resources, (3 learning model IPS-based environment effectively creating a way of life together peacefully, increase the intensity of togetherness and mutual respect (4 learning model IPS-based environment can improve student learning outcomes, (5 there are differences in the expression of attitudes and results learning among students who are located in the area of conflict with students who are outside the area of conflict (6 analysis of the scale of attitudes among school students da SMA result rewards high school students to the values of unity and nation, respect for diversity and peaceful coexistence, It is recommended that the Department of Education authority as an institution of Trustees and the development of social and cultural values in the province can apply IPS learning model based environments.

A Web-Based Learning Support System for Inquiry-Based Learning

Science.gov (United States)

Kim, Dong Won; Yao, Jingtao

The emergence of the Internet and Web technology makes it possible to implement the ideals of inquiry-based learning, in which students seek truth, information, or knowledge by questioning. Web-based learning support systems can provide a good framework for inquiry-based learning. This article presents a study on a Web-based learning support system called Online Treasure Hunt. The Web-based learning support system mainly consists of a teaching support subsystem, a learning support subsystem, and a treasure hunt game. The teaching support subsystem allows instructors to design their own inquiry-based learning environments. The learning support subsystem supports students' inquiry activities. The treasure hunt game enables students to investigate new knowledge, develop ideas, and review their findings. Online Treasure Hunt complies with a treasure hunt model. The treasure hunt model formalizes a general treasure hunt game to contain the learning strategies of inquiry-based learning. This Web-based learning support system empowered with the online-learning game and founded on the sound learning strategies furnishes students with the interactive and collaborative student-centered learning environment.

Design of Composite Structures Using Knowledge-Based and Case Based Reasoning

Science.gov (United States)

Lambright, Jonathan Paul

1996-01-01

A method of using knowledge based and case based reasoning to assist designers during conceptual design tasks of composite structures was proposed. The cooperative use of heuristics, procedural knowledge, and previous similar design cases suggests a potential reduction in design cycle time and ultimately product lead time. The hypothesis of this work is that the design process of composite structures can be improved by using Case-Based Reasoning (CBR) and Knowledge-Based (KB) reasoning in the early design stages. The technique of using knowledge-based and case-based reasoning facilitates the gathering of disparate information into one location that is easily and readily available. The method suggests that the inclusion of downstream life-cycle issues into the conceptual design phase reduces potential of defective, and sub-optimal composite structures. Three industry experts were interviewed extensively. The experts provided design rules, previous design cases, and test problems. A Knowledge Based Reasoning system was developed using the CLIPS (C Language Interpretive Procedural System) environment and a Case Based Reasoning System was developed using the Design Memory Utility For Sharing Experiences (MUSE) xviii environment. A Design Characteristic State (DCS) was used to document the design specifications, constraints, and problem areas using attribute-value pair relationships. The DCS provided consistent design information between the knowledge base and case base. Results indicated that the use of knowledge based and case based reasoning provided a robust design environment for composite structures. The knowledge base provided design guidance from well defined rules and procedural knowledge. The case base provided suggestions on design and manufacturing techniques based on previous similar designs and warnings of potential problems and pitfalls. The case base complemented the knowledge base and extended the problem solving capability beyond the existence of

Feature-Based versus Category-Based Induction with Uncertain Categories

Science.gov (United States)

Griffiths, Oren; Hayes, Brett K.; Newell, Ben R.

2012-01-01

Previous research has suggested that when feature inferences have to be made about an instance whose category membership is uncertain, feature-based inductive reasoning is used to the exclusion of category-based induction. These results contrast with the observation that people can and do use category-based induction when category membership is…

WPS criterion proposition based on experimental data base interpretation

International Nuclear Information System (INIS)

Chapuliot, S.; Izard, J.P.; Moinereau, D.; Marie, S.

2011-01-01

This article gives the background and the methodology developed to define a K J based criterion for brittle fracture of Reactor Pressure Vessel (RPV) submitted to Pressurized Thermal Shock (PTS), and taking into account Warm Pre Stressing effect (WPS). The first step of this methodology is the constitution of an experimental data base. This work was performed through bibliography and partnerships, and allows merging experimental results dealing with: -) Various ferritic steels; -) Various material states (as received, thermally aged, irradiated...); -) Various mode of fracture (cleavage, inter-granular, mixed mode); -) Various specimen geometry and size (CT, SENB, mock-ups); -) Various thermo-mechanical transients. Based on this experimental data base, a simple K J based limit is proposed and compared to experimental results. Parametric studies are performed in order to define the main parameters of the problem. Finally, a simple proposition based on a detailed analysis of tests results is performed. This proposition giving satisfactory results in every cases, it constitutes a good candidate for integration in French RSE-M code for in service assessment. (authors)

Set-Based Discrete Particle Swarm Optimization Based on Decomposition for Permutation-Based Multiobjective Combinatorial Optimization Problems.

Science.gov (United States)

Yu, Xue; Chen, Wei-Neng; Gu, Tianlong; Zhang, Huaxiang; Yuan, Huaqiang; Kwong, Sam; Zhang, Jun

2017-08-07

This paper studies a specific class of multiobjective combinatorial optimization problems (MOCOPs), namely the permutation-based MOCOPs. Many commonly seen MOCOPs, e.g., multiobjective traveling salesman problem (MOTSP), multiobjective project scheduling problem (MOPSP), belong to this problem class and they can be very different. However, as the permutation-based MOCOPs share the inherent similarity that the structure of their search space is usually in the shape of a permutation tree, this paper proposes a generic multiobjective set-based particle swarm optimization methodology based on decomposition, termed MS-PSO/D. In order to coordinate with the property of permutation-based MOCOPs, MS-PSO/D utilizes an element-based representation and a constructive approach. Through this, feasible solutions under constraints can be generated step by step following the permutation-tree-shaped structure. And problem-related heuristic information is introduced in the constructive approach for efficiency. In order to address the multiobjective optimization issues, the decomposition strategy is employed, in which the problem is converted into multiple single-objective subproblems according to a set of weight vectors. Besides, a flexible mechanism for diversity control is provided in MS-PSO/D. Extensive experiments have been conducted to study MS-PSO/D on two permutation-based MOCOPs, namely the MOTSP and the MOPSP. Experimental results validate that the proposed methodology is promising.

Evidence-based guidelines, time-based health outcomes, and the Matthew effect

NARCIS (Netherlands)

M.L.E. Essink-Bot (Marie-Louise); M.E. Kruijshaar (Michelle); J.J.M. Barendregt (Jan); L.G.A. Bonneux (Luc)

2007-01-01

textabstractBackground: Cardiovascular risk management guidelines are 'risk based'; health economists' practice is 'time based'. The 'medical' risk-based allocation model maximises numbers of deaths prevented by targeting subjects at high risk, for example, elderly and smokers. The time-based model

Evidence-based guidelines, time-based health outcomes, and the Matthew effect

NARCIS (Netherlands)

Essink-Bot, Marie-Louise; Kruijshaar, Michelle E.; Barendregt, Jan J.; Bonneux, Luc G. A.

2007-01-01

BACKGROUND: Cardiovascular risk management guidelines are 'risk based'; health economists' practice is 'time based'. The 'medical' risk-based allocation model maximises numbers of deaths prevented by targeting subjects at high risk, for example, elderly and smokers. The time-based model maximises

0-6621 : developing a mixture-based specification for flexible base.

Science.gov (United States)

2012-08-01

The Texas Department of Transportation : (TxDOT) currently utilizes Item 247, Flexible : Base, to specify a foundation course of flexible : base utilized in a pavement. Base materials are : not allowed to be used by the contractors until : the ...

Acids and bases solvent effects on acid-base strenght

CERN Document Server

Cox, Brian G

2013-01-01

Acids and bases are ubiquitous in chemistry. Our understanding of them, however, is dominated by their behaviour in water. Transfer to non-aqueous solvents leads to profound changes in acid-base strengths and to the rates and equilibria of many processes: for example, synthetic reactions involving acids, bases and nucleophiles; isolation of pharmaceutical actives through salt formation; formation of zwitter- ions in amino acids; and chromatographic separation of substrates. This book seeks to enhance our understanding of acids and bases by reviewing and analysing their behaviour in non-aqueous solvents. The behaviour is related where possible to that in water, but correlations and contrasts between solvents are also presented.

Characteristic-Based, Task-Based, and Results-Based: Three Value Systems for Assessing Professionally Produced Technical Communication Products.

Science.gov (United States)

Carliner, Saul

2003-01-01

Notes that technical communicators have developed different methodologies for evaluating the effectiveness of their work, such as editing, usability testing, and determining the value added. Explains that at least three broad value systems underlie the assessment practices: characteristic-based, task-based, and results-based. Concludes that the…

Designing Android Based Augmented Reality Location-Based Service Application

Directory of Open Access Journals (Sweden)

Alim Hardiansyah

2018-01-01

Full Text Available Android is an operating system for Linux based smartphone. Android provides an open platform for the developers to create their own application. The most developed and used application now is location based application. This application gives personalization service for mobile device user and is customized to their location. Location based service also gives an opportunity for the developers to develop and increase the value of service. One of the technologies that could be combined with location based application is augmented reality. Augmented reality combines the virtual world with the real one. By the assistance of augmented reality, our surrounding environment could interact in digital form. Information of objects and environment surround us could be added to the augmented reality system and presented. Based on the background, the writers tried to implement those technologies on now rapidly developing android application as a final project to achieve bachelor degree in Department of Informatics Engineering, Faculty of Information Technology and Visual Communication, Al Kamal Science and Technology Institute. This application could be functioned to locate school by using location based service technology with the assistance of navigational applications such as waze and google maps, in form of live direction process through the smartphone

Selective Distance-Based K+ Quantification on Paper-Based Microfluidics.

Science.gov (United States)

Gerold, Chase T; Bakker, Eric; Henry, Charles S

2018-04-03

In this study, paper-based microfluidic devices (μPADs) capable of K + quantification in aqueous samples, as well as in human serum, using both colorimetric and distance-based methods are described. A lipophilic phase containing potassium ionophore I (valinomycin) was utilized to achieve highly selective quantification of K + in the presence of Na + , Li + , and Mg 2+ ions. Successful addition of a suspended lipophilic phase to a wax printed paper-based device is described and offers a solution to current approaches that rely on organic solvents, which damage wax barriers. The approach provides an avenue for future alkali/alkaline quantification utilizing μPADs. Colorimetric spot tests allowed for K + quantification from 0.1-5.0 mM using only 3.00 μL of sample solution. Selective distance-based quantification required small sample volumes (6.00 μL) and gave responses sensitive enough to distinguish between 1.0 and 2.5 mM of sample K + . μPADs using distance-based methods were also capable of differentiating between 4.3 and 6.9 mM K + in human serum samples. Distance-based methods required no digital analysis, electronic hardware, or pumps; any steps required for quantification could be carried out using the naked eye.

VectorBase

Data.gov (United States)

U.S. Department of Health & Human Services — VectorBase is a Bioinformatics Resource Center for invertebrate vectors. It is one of four Bioinformatics Resource Centers funded by NIAID to provide web-based...

Owner-Based Role-Based Access Control OB-RBAC

NARCIS (Netherlands)

Saffarian, M.; Sadighi, Babak

Administration of an access control model deals with the question of who is authorized to update policies defined on the basis of that model. One of the models whose administration has absorbed relatively large research is the Role-Based Access Control (RBAC) model. All the existing role-based

Characteristics Data Base: Programmer's guide to the LWR Quantities Data Base

International Nuclear Information System (INIS)

Jones, K.E.; Moore, R.S.

1990-08-01

The LWR Quantities Data Base is a menu-driven PC data base developed as part of OCRWM's waste, technical data base on the characteristics of potential repository wastes, which also includes non-LWR spent fuel, high-level and other materials. This programmer's guide completes the documentation for the LWR Quantities Data Base, the user's guide having been published previously. The PC data base itself may be requested from the Oak Ridge National Laboratory, using the order form provided in Volume 1 of publication DOE/RW-0184

Interaction between scene-based and array-based contextual cueing.

Science.gov (United States)

Rosenbaum, Gail M; Jiang, Yuhong V

2013-07-01

Contextual cueing refers to the cueing of spatial attention by repeated spatial context. Previous studies have demonstrated distinctive properties of contextual cueing by background scenes and by an array of search items. Whereas scene-based contextual cueing reflects explicit learning of the scene-target association, array-based contextual cueing is supported primarily by implicit learning. In this study, we investigated the interaction between scene-based and array-based contextual cueing. Participants searched for a target that was predicted by both the background scene and the locations of distractor items. We tested three possible patterns of interaction: (1) The scene and the array could be learned independently, in which case cueing should be expressed even when only one cue was preserved; (2) the scene and array could be learned jointly, in which case cueing should occur only when both cues were preserved; (3) overshadowing might occur, in which case learning of the stronger cue should preclude learning of the weaker cue. In several experiments, we manipulated the nature of the contextual cues present during training and testing. We also tested explicit awareness of scenes, scene-target associations, and arrays. The results supported the overshadowing account: Specifically, scene-based contextual cueing precluded array-based contextual cueing when both were predictive of the location of a search target. We suggest that explicit, endogenous cues dominate over implicit cues in guiding spatial attention.

Brain-Based Learning and Standards-Based Elementary Science.

Science.gov (United States)

Konecki, Loretta R.; Schiller, Ellen

This paper explains how brain-based learning has become an area of interest to elementary school science teachers, focusing on the possible relationships between, and implications of, research on brain-based learning to the teaching of science education standards. After describing research on the brain, the paper looks at three implications from…

BEAT: A Web-Based Boolean Expression Fault-Based Test Case Generation Tool

Science.gov (United States)

Chen, T. Y.; Grant, D. D.; Lau, M. F.; Ng, S. P.; Vasa, V. R.

2006-01-01

BEAT is a Web-based system that generates fault-based test cases from Boolean expressions. It is based on the integration of our several fault-based test case selection strategies. The generated test cases are considered to be fault-based, because they are aiming at the detection of particular faults. For example, when the Boolean expression is in…

Rule-Based and Case-Based Reasoning in Housing Prices

OpenAIRE

Gabrielle Gayer; Itzhak Gilboa; Offer Lieberman

2004-01-01

People reason about real-estate prices both in terms of general rules and in terms of analogies to similar cases. We propose to empirically test which mode of reasoning fits the data better. To this end, we develop the statistical techniques required for the estimation of the case-based model. It is hypothesized that case-based reasoning will have relatively more explanatory power in databases of rental apartments, whereas rule-based reasoning will have a relative advantage in sales data. We ...

Object-Based Benefits without Object-Based Representations

OpenAIRE

Alvarez, George Angelo; Fougnie, Daryl; Cormiea, Sarah M

2012-01-01

The organization of visual information into objects strongly influences visual memory: Displays with objects defined by two features (e.g. color, orientation) are easier to remember than displays with twice as many objects defined by one feature (Olson & Jiang, 2002). Existing theories suggest that this ‘object-benefit’ is based on object-based limitations in working memory: because a limited number of objects can be stored, packaging features together so that fewer objects have to be remembe...

An Ontology-Based Tourism Recommender System Based on Spreading Activation Model

Science.gov (United States)

Bahramian, Z.; Abbaspour, R. Ali

2015-12-01

A tourist has time and budget limitations; hence, he needs to select points of interest (POIs) optimally. Since the available information about POIs is overloading, it is difficult for a tourist to select the most appreciate ones considering preferences. In this paper, a new travel recommender system is proposed to overcome information overload problem. A recommender system (RS) evaluates the overwhelming number of POIs and provides personalized recommendations to users based on their preferences. A content-based recommendation system is proposed, which uses the information about the user's preferences and POIs and calculates a degree of similarity between them. It selects POIs, which have highest similarity with the user's preferences. The proposed content-based recommender system is enhanced using the ontological information about tourism domain to represent both the user profile and the recommendable POIs. The proposed ontology-based recommendation process is performed in three steps including: ontology-based content analyzer, ontology-based profile learner, and ontology-based filtering component. User's feedback adapts the user's preferences using Spreading Activation (SA) strategy. It shows the proposed recommender system is effective and improves the overall performance of the traditional content-based recommender systems.

AN ONTOLOGY-BASED TOURISM RECOMMENDER SYSTEM BASED ON SPREADING ACTIVATION MODEL

Directory of Open Access Journals (Sweden)

Z. Bahramian

2015-12-01

Full Text Available A tourist has time and budget limitations; hence, he needs to select points of interest (POIs optimally. Since the available information about POIs is overloading, it is difficult for a tourist to select the most appreciate ones considering preferences. In this paper, a new travel recommender system is proposed to overcome information overload problem. A recommender system (RS evaluates the overwhelming number of POIs and provides personalized recommendations to users based on their preferences. A content-based recommendation system is proposed, which uses the information about the user’s preferences and POIs and calculates a degree of similarity between them. It selects POIs, which have highest similarity with the user’s preferences. The proposed content-based recommender system is enhanced using the ontological information about tourism domain to represent both the user profile and the recommendable POIs. The proposed ontology-based recommendation process is performed in three steps including: ontology-based content analyzer, ontology-based profile learner, and ontology-based filtering component. User’s feedback adapts the user’s preferences using Spreading Activation (SA strategy. It shows the proposed recommender system is effective and improves the overall performance of the traditional content-based recommender systems.

Contests versus Norms: Implications of Contest-Based and Norm-Based Intervention Techniques.

Science.gov (United States)

Bergquist, Magnus; Nilsson, Andreas; Hansla, André

2017-01-01

Interventions using either contests or norms can promote environmental behavioral change. Yet research on the implications of contest-based and norm-based interventions is lacking. Based on Goal-framing theory, we suggest that a contest-based intervention frames a gain goal promoting intensive but instrumental behavioral engagement. In contrast, the norm-based intervention was expected to frame a normative goal activating normative obligations for targeted and non-targeted behavior and motivation to engage in pro-environmental behaviors in the future. In two studies participants ( n = 347) were randomly assigned to either a contest- or a norm-based intervention technique. Participants in the contest showed more intensive engagement in both studies. Participants in the norm-based intervention tended to report higher intentions for future energy conservation (Study 1) and higher personal norms for non-targeted pro-environmental behaviors (Study 2). These findings suggest that contest-based intervention technique frames a gain goal, while norm-based intervention frames a normative goal.

Contests versus Norms: Implications of Contest-Based and Norm-Based Intervention Techniques

Directory of Open Access Journals (Sweden)

Magnus Bergquist

2017-11-01

Full Text Available Interventions using either contests or norms can promote environmental behavioral change. Yet research on the implications of contest-based and norm-based interventions is lacking. Based on Goal-framing theory, we suggest that a contest-based intervention frames a gain goal promoting intensive but instrumental behavioral engagement. In contrast, the norm-based intervention was expected to frame a normative goal activating normative obligations for targeted and non-targeted behavior and motivation to engage in pro-environmental behaviors in the future. In two studies participants (n = 347 were randomly assigned to either a contest- or a norm-based intervention technique. Participants in the contest showed more intensive engagement in both studies. Participants in the norm-based intervention tended to report higher intentions for future energy conservation (Study 1 and higher personal norms for non-targeted pro-environmental behaviors (Study 2. These findings suggest that contest-based intervention technique frames a gain goal, while norm-based intervention frames a normative goal.

Embracing a competency-based specialty curriculum for community-based nursing roles.

Science.gov (United States)

Levin, Pamela F; Swider, Susan M; Breakwell, Susan; Cowell, Julia M; Reising, Virginia

2013-01-01

The Quad Council competencies for public health nursing (PHN) provide guidance in developing curricula at both the generalist and specialist level. However, these competencies are based on nursing roles in traditional public health agencies and community/public health is defined more broadly than official agency practice. The question arises as to whether community-based specialties require largely the same knowledge and skill set as PHN. The purpose of the competency cross-mapping project reported here was to (a) assess the intersection of the Quad Council competencies with four community-based specialties and (b) ensure the appropriateness of a Quad Council-based curriculum to prepare graduates across these four specialties (home health, occupational health, environmental health, and school nursing). This article details the multistep cross-mapping process, including validation with practice leaders. Results indicate strong alignment of community-based specialty competencies with Quad Council competencies. Community-based specialty-specific content that did not align well is identified, along with examples of didactic and clinical strategies to address gaps. This work indicates that a Quad Council-based curriculum is appropriate to prepare graduates in community-based specialties when attention to the specialty-specific competencies in the clinical setting is included. This work guides the development of a doctorate of nursing practice curriculum in PHN, encompassing the four additional community-based specialties. © 2013 Wiley Periodicals, Inc.

Foundry based approach for InP based PIC development

NARCIS (Netherlands)

Smit, M.K.

2014-01-01

Europe is making significant investments in development of generic photonic foundry platform infrastructures for InP-based and Silicon Photonic ICs. Here we present the present status for the InP-based JePPIX platform.

Managing the Gap between Curriculum Based and Problem Based Learning

DEFF Research Database (Denmark)

Bygholm, Ann; Buus, Lillian

2009-01-01

/or but rather both/and. In this paper we describe an approach to design and delivery of online courses in computer science which on the one hand is based on a specified curriculum and on the other hand gives room for different learning strategies, problem based learning being one of them. We discuss......Traditionally there has been a clear distinction between curriculum based and problem based approaches to accomplish learning. Preferred approaches depend of course on conviction, culture, traditions and also on the specific learning situation. We will argue that it is not a question of either...

Groebner Bases Based Verification Solution for SystemVerilog Concurrent Assertions

Directory of Open Access Journals (Sweden)

Ning Zhou

2014-01-01

of polynomial ring algebra to perform SystemVerilog assertion verification over digital circuit systems. This method is based on Groebner bases theory and sequential properties checking. We define a constrained subset of SVAs so that an efficient polynomial modeling mechanism for both circuit descriptions and assertions can be applied. We present an algorithm framework based on the algebraic representations using Groebner bases for concurrent SVAs checking. Case studies show that computer algebra can provide canonical symbolic representations for both assertions and circuit designs and can act as a novel solver engine from the viewpoint of symbolic computation.

A Computer-Based Simulation of an Acid-Base Titration

Science.gov (United States)

Boblick, John M.

1971-01-01

Reviews the advantages of computer simulated environments for experiments, referring in particular to acid-base titrations. Includes pre-lab instructions and a sample computer printout of a student's use of an acid-base simulation. Ten references. (PR)

Research on the comparison of performance-based concept and force-based concept

Science.gov (United States)

Wu, Zeyu; Wang, Dongwei

2011-03-01

There are two ideologies about structure design: force-based concept and performance-based concept. Generally, if the structure operates during elastic stage, the two philosophies usually attain the same results. But beyond that stage, the shortage of force-based method is exposed, and the merit of performance-based is displayed. Pros and cons of each strategy are listed herein, and then which structure is best suitable to each method analyzed. At last, a real structure is evaluated by adaptive pushover method to verify that performance-based method is better than force-based method.

Priority-Based Hierarchical Operational Management for Multiagent-Based Microgrids

Directory of Open Access Journals (Sweden)

Takumi Kato

2014-03-01

Full Text Available Electricity consumption in the world is constantly increasing, making our lives become more and more dependent on electricity. There are several new paradigms proposed in the field of power grids. In Japan, especially after the Great East Japan Earthquake in March 2011, the new power grid paradigms are expected to be more resilient to survive several difficulties during disasters. In this paper, we focus on microgrids and propose priority-based hierarchical operational management for multiagent-based microgrids. The proposed management is a new multiagent-based load shedding scheme and multiagent-based hierarchical architecture to realize such resilient microgrids. We developed a prototype system and performed an evaluation of the proposed management using the developed system. The result of the evaluation shows the effectiveness of our proposal in power shortage situations, such as disasters.

Feature-based attention is functionally distinct from relation-based attention: The double dissociation between color-based capture and color-relation-based capture of attention.

Science.gov (United States)

Du, Feng; Jiao, Jun

2016-04-01

The present study used a spatial blink task and a cuing task to examine the boundary between feature-based capture and relation-based capture. Feature-based capture occurs when distractors match the target feature such as target color. The occurrence of relation-based capture is contingent upon the feature relation between target and distractor (e.g., color relation). The results show that color distractors that match the target-nontarget color relation do not consistently capture attention when they appear outside of the attentional window, but distractors appearing outside the attentional window that match the target color consistently capture attention. In contrast, color distractors that best match the target-nontarget color relation but not the target color, are more likely to capture attention when they appear within the attentional window. Consistently, color cues that match the target-nontarget color relation produce a cuing effect when they appear within the attentional window, while target-color matched cues do not. Such a double dissociation between color-based capture and color-relation-based capture indicates functionally distinct mechanisms for these 2 types of attentional selection. This also indicates that the spatial blink task and the uninformative cuing task are measuring distinctive aspects of involuntary attention. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Skull base tumours

Energy Technology Data Exchange (ETDEWEB)

Borges, Alexandra [Instituto Portugues de Oncologia Francisco Gentil, Servico de Radiologia, Rua Professor Lima Basto, 1093 Lisboa Codex (Portugal)], E-mail: borgesalexandra@clix.pt

2008-06-15

With the advances of cross-sectional imaging radiologists gained an increasing responsibility in the management of patients with skull base pathology. As this anatomic area is hidden to clinical exam, surgeons and radiation oncologists have to rely on imaging studies to plan the most adequate treatment. To fulfil these endeavour radiologists need to be knowledgeable about skull base anatomy, about the main treatment options available, their indications and contra-indications and needs to be aware of the wide gamut of pathologies seen in this anatomic region. This article will provide a radiologists' friendly approach to the central skull base and will review the most common central skull base tumours and tumours intrinsic to the bony skull base.

Skull base tumours

International Nuclear Information System (INIS)

Borges, Alexandra

2008-01-01

With the advances of cross-sectional imaging radiologists gained an increasing responsibility in the management of patients with skull base pathology. As this anatomic area is hidden to clinical exam, surgeons and radiation oncologists have to rely on imaging studies to plan the most adequate treatment. To fulfil these endeavour radiologists need to be knowledgeable about skull base anatomy, about the main treatment options available, their indications and contra-indications and needs to be aware of the wide gamut of pathologies seen in this anatomic region. This article will provide a radiologists' friendly approach to the central skull base and will review the most common central skull base tumours and tumours intrinsic to the bony skull base

State-based versus reward-based motivation in younger and older adults.

Science.gov (United States)

Worthy, Darrell A; Cooper, Jessica A; Byrne, Kaileigh A; Gorlick, Marissa A; Maddox, W Todd

2014-12-01

Recent decision-making work has focused on a distinction between a habitual, model-free neural system that is motivated toward actions that lead directly to reward and a more computationally demanding goal-directed, model-based system that is motivated toward actions that improve one's future state. In this article, we examine how aging affects motivation toward reward-based versus state-based decision making. Participants performed tasks in which one type of option provided larger immediate rewards but the alternative type of option led to larger rewards on future trials, or improvements in state. We predicted that older adults would show a reduced preference for choices that led to improvements in state and a greater preference for choices that maximized immediate reward. We also predicted that fits from a hybrid reinforcement-learning model would indicate greater model-based strategy use in younger than in older adults. In line with these predictions, older adults selected the options that maximized reward more often than did younger adults in three of the four tasks, and modeling results suggested reduced model-based strategy use. In the task where older adults showed similar behavior to younger adults, our model-fitting results suggested that this was due to the utilization of a win-stay-lose-shift heuristic rather than a more complex model-based strategy. Additionally, within older adults, we found that model-based strategy use was positively correlated with memory measures from our neuropsychological test battery. We suggest that this shift from state-based to reward-based motivation may be due to age related declines in the neural structures needed for more computationally demanding model-based decision making.

Image based Monument Recognition using Graph based Visual Saliency

DEFF Research Database (Denmark)

Kalliatakis, Grigorios; Triantafyllidis, Georgios

2013-01-01

This article presents an image-based application aiming at simple image classification of well-known monuments in the area of Heraklion, Crete, Greece. This classification takes place by utilizing Graph Based Visual Saliency (GBVS) and employing Scale Invariant Feature Transform (SIFT) or Speeded......, the images have been previously processed according to the Graph Based Visual Saliency model in order to keep either SIFT or SURF features corresponding to the actual monuments while the background “noise” is minimized. The application is then able to classify these images, helping the user to better...

Convergent Filter Bases

Directory of Open Access Journals (Sweden)

Coghetto Roland

2015-09-01

Full Text Available We are inspired by the work of Henri Cartan [16], Bourbaki [10] (TG. I Filtres and Claude Wagschal [34]. We define the base of filter, image filter, convergent filter bases, limit filter and the filter base of tails (fr: filtre des sections.

QuickBase

CERN Document Server

Conner, Nancy

2007-01-01

Ready to put Intuit's QuickBase to work? Our new Missing Manual shows you how to capture, modify, share, and manage data and documents with this web-based data-sharing program quickly and easily. No longer do you have to coordinate your team through a blizzard of emails or play frustrating games of "guess which document is the right one."QuickBase saves your organization time and money, letting you manage and share the information that makes your business tick: sales figures, project timelines, drafts of documents, purchase or work requests--whatever information you need to keep business flowi

Merits of using andalusite-based refractories compared to bauxite-based refractories

OpenAIRE

Nyoka, M.; Brazier, D.; Courtney, T.; Parry, R.A.

2013-01-01

Historically bauxite-based refractories have been used in applications where andalusite-based refractories could work. Bauxite-based refractories were chosen over andalusite-based refractories mainly because of the availability of low-cost Chinese bauxite and also because many furnaces were designed by international companies that cannot easily access high-quality products. Currently, the availability of low-cost bauxite is under threat as a result of high export duties and tariffs as well as...

Swarm-based medicine.

Science.gov (United States)

Putora, Paul Martin; Oldenburg, Jan

2013-09-19

Occasionally, medical decisions have to be taken in the absence of evidence-based guidelines. Other sources can be drawn upon to fill in the gaps, including experience and intuition. Authorities or experts, with their knowledge and experience, may provide further input--known as "eminence-based medicine". Due to the Internet and digital media, interactions among physicians now take place at a higher rate than ever before. With the rising number of interconnected individuals and their communication capabilities, the medical community is obtaining the properties of a swarm. The way individual physicians act depends on other physicians; medical societies act based on their members. Swarm behavior might facilitate the generation and distribution of knowledge as an unconscious process. As such, "swarm-based medicine" may add a further source of information to the classical approaches of evidence- and eminence-based medicine. How to integrate swarm-based medicine into practice is left to the individual physician, but even this decision will be influenced by the swarm.

Touch BASE

CERN Multimedia

Antonella Del Rosso

2015-01-01

In a recent Nature article (see here), the BASE collaboration reported the most precise comparison of the charge-to-mass ratio of the proton to its antimatter equivalent, the antiproton. This result is just the beginning and many more challenges lie ahead.   CERN's AD Hall, where the BASE experiment is set-up. The Baryon Antibaryon Symmetry Experiment (BASE) was approved in June 2013 and was ready to take data in August 2014. During these 14 months, the BASE collaboration worked hard to set up its four cryogenic Penning traps, which are the heart of the whole experiment. As their name indicates, these magnetic devices are used to trap antiparticles – antiprotons coming from the Antiproton Decelerator – and particles of matter – negative hydrogen ions produced in the system by interaction with a degrader that slows the antiprotons down, allowing scientists to perform their measurements. “We had very little time to set up the wh...

Evaluation of radiosurgery techniques–Cone-based linac radiosurgery vs tomotherapy-based radiosurgery

International Nuclear Information System (INIS)

Yip, Ho Yin; Mui, Wing Lun A.; Lee, Joseph W.Y.; Fung, Winky Wing Ki; Chan, Jocelyn M.T.; Chiu, G.; Law, Maria Y.Y.

2013-01-01

Performances of radiosurgery of intracranial lesions between cone-based Linac system and Tomotherapy-based system were compared in terms of dosimetry and time. Twelve patients with single intracranial lesion treated with cone-based Linac radiosurgery system from 2005 to 2009 were replanned for Tomotherapy-based radiosurgery treatment. The conformity index, homogeneity index (HI), and gradient score index (GSI) of each case was calculated. The Wilcoxon matched-pair test was used to compare the 3 indices between both systems. The cases with regular target (n = 6) and those with irregular target (n = 6) were further analyzed separately. The estimated treatment time between both systems was also compared. Significant differences were found in HI (p = 0.05) and in GSI (p = 0.03) for the whole group. Cone-based radiosurgery was better in GSI whereas Tomotherapy-based radiosurgery was better in HI. Cone-based radiosurgery was better in conformity index (p = 0.03) and GSI (p = 0.03) for regular targets, whereas Tomotherapy-based radiosurgery system performed significantly better in HI (p = 0.03) for irregular targets. The estimated total treatment time for Tomotherapy-based radiosurgery ranged from 24 minutes to 35 minutes, including 15 minutes of pretreatment megavoltage computed tomography (MVCT) and image registration, whereas that for cone-based radiosurgery ranged from 15 minutes for 1 isocenter to 75 minutes for 5 isocenters. As a rule of thumb, Tomotherapy-based radiosurgery system should be the first-line treatment for irregular lesions because of better dose homogeneity and shorter treatment time. Cone-based Linac radiosurgery system should be the treatment of choice for regular targets because of the better dose conformity, rapid dose fall-off, and reasonable treatment time

Evaluation of radiosurgery techniques–Cone-based linac radiosurgery vs tomotherapy-based radiosurgery

Energy Technology Data Exchange (ETDEWEB)

Yip, Ho Yin, E-mail: hoyinyip@yahoo.com.hk [Department of Radiotherapy, Hong Kong Sanatorium and Hospital, Happy Valley, Hong Kong (China); Mui, Wing Lun A.; Lee, Joseph W.Y.; Fung, Winky Wing Ki; Chan, Jocelyn M.T.; Chiu, G. [Department of Radiotherapy, Hong Kong Sanatorium and Hospital, Happy Valley, Hong Kong (China); Law, Maria Y.Y. [Medical Physics and Research Department, Hong Kong Sanatorium and Hospital, Happy Valley, Hong Kong (China)

2013-07-01

Performances of radiosurgery of intracranial lesions between cone-based Linac system and Tomotherapy-based system were compared in terms of dosimetry and time. Twelve patients with single intracranial lesion treated with cone-based Linac radiosurgery system from 2005 to 2009 were replanned for Tomotherapy-based radiosurgery treatment. The conformity index, homogeneity index (HI), and gradient score index (GSI) of each case was calculated. The Wilcoxon matched-pair test was used to compare the 3 indices between both systems. The cases with regular target (n = 6) and those with irregular target (n = 6) were further analyzed separately. The estimated treatment time between both systems was also compared. Significant differences were found in HI (p = 0.05) and in GSI (p = 0.03) for the whole group. Cone-based radiosurgery was better in GSI whereas Tomotherapy-based radiosurgery was better in HI. Cone-based radiosurgery was better in conformity index (p = 0.03) and GSI (p = 0.03) for regular targets, whereas Tomotherapy-based radiosurgery system performed significantly better in HI (p = 0.03) for irregular targets. The estimated total treatment time for Tomotherapy-based radiosurgery ranged from 24 minutes to 35 minutes, including 15 minutes of pretreatment megavoltage computed tomography (MVCT) and image registration, whereas that for cone-based radiosurgery ranged from 15 minutes for 1 isocenter to 75 minutes for 5 isocenters. As a rule of thumb, Tomotherapy-based radiosurgery system should be the first-line treatment for irregular lesions because of better dose homogeneity and shorter treatment time. Cone-based Linac radiosurgery system should be the treatment of choice for regular targets because of the better dose conformity, rapid dose fall-off, and reasonable treatment time.

Nasal base narrowing: the combined alar base excision technique.

Science.gov (United States)

Foda, Hossam M T

2007-01-01

To evaluate the role of the combined alar base excision technique in narrowing the nasal base and correcting excessive alar flare. The study included 60 cases presenting with a wide nasal base and excessive alar flaring. The surgical procedure combined an external alar wedge resection with an internal vestibular floor excision. All cases were followed up for a mean of 32 (range, 12-144) months. Nasal tip modification and correction of any preexisting caudal septal deformities were always completed before the nasal base narrowing. The mean width of the external alar wedge excised was 7.2 (range, 4-11) mm, whereas the mean width of the sill excision was 3.1 (range, 2-7) mm. Completing the internal excision first resulted in a more conservative external resection, thus avoiding any blunting of the alar-facial crease. No cases of postoperative bleeding, infection, or keloid formation were encountered, and the external alar wedge excision healed with an inconspicuous scar that was well hidden in the depth of the alar-facial crease. Finally, the risk of notching of the alar rim, which can occur at the junction of the external and internal excisions, was significantly reduced by adopting a 2-layered closure of the vestibular floor (P = .01). The combined alar base excision resulted in effective narrowing of the nasal base with elimination of excessive alar flare. Commonly feared complications, such as blunting of the alar-facial crease or notching of the alar rim, were avoided by using simple modifications in the technique of excision and closure.

Developing effective web-based regional anesthesia education: a randomized study evaluating case-based versus non-case-based module design.

Science.gov (United States)

Kopp, Sandra L; Smith, Hugh M

2011-01-01

Little is known about the use of Web-based education in regional anesthesia training. Benefits of Web-based education include the ability to standardize learning material quality and content, build appropriate learning progressions, use interactive multimedia technologies, and individualize delivery of course materials. The goals of this investigation were (1) to determine whether module design influences regional anesthesia knowledge acquisition, (2) to characterize learner preference patterns among anesthesia residents, and (3) to determine whether learner preferences play a role in knowledge acquisition. Direct comparison of knowledge assessments, learning styles, and learner preferences will be made between an interactive case-based and a traditional textbook-style module design. Forty-three Mayo Clinic anesthesiology residents completed 2 online modules, a knowledge pretest, posttest, an Index of Learning Styles assessment, and a participant satisfaction survey. Interscalene and lumbar plexus regional techniques were selected as the learning content for 4 Web modules constructed using the Blackboard Vista coursework application. One traditional textbook-style module and 1 interactive case-based module were designed for each of the interscalene and lumbar plexus techniques. Participants scored higher on the postmodule knowledge assessment for both of the interscalene and lumbar plexus modules. Postmodule knowledge performance scores were independent of both module design (interactive case-based versus traditional textbook style) and learning style preferences. However, nearly all participants reported a preference for Web-based learning and believe that it should be used in anesthesia resident education. Participants did not feel that Web-base learning should replace the current lecture-based curriculum. All residents scored higher on the postmodule knowledge assessment, but this improvement was independent of the module design and individual learning styles

Nuclear Fusion Project. Semi-annual report of the Association KfK/EURATOM

International Nuclear Information System (INIS)

Kast, G.

1988-10-01

Report on technology tasks: Blanket designs studies; Computational tools for neutronics; Corrosion and fatigue of structural materials in Pb-17Li; Tritium extraction from liquid Pb-17Li by the use of solid getters; Development of ceramic breeder materials; The large coil task; Development of high field composite conductors; Superconducting poloidal field coil development; Poloidal field coil for TORE SUPRA as NET-Prototype Coil; Structural materials Fatigue characterization at 4 K; Low electrical conductivity structures development; MANET 1; Pre- and post-irradiation fatigue properties and fracture toughness of 1.4914 martensitic steel; In-pile creep-fatigue testing of type 316 and 1.4914 steels; Ceramics for first-wall protection and for RF windows; Development of low activation ferritic-martensitic steels; Design study of plasma facing components and shield; Procedures and tools for structural design evaluation; Theory and tools for evaluation of magnetic field effects on liquid-metal breeder blankets; Studies of pebble beds of ceramic compounds; Background studies on remote maintenance; Handling equipment for in-vessel components; Safety aspects of the cryosystem and superconducting magnets; Overall plant accident scenarios and safety guidelines for NET; Generic environmental impact assessment for a fusion facility; Industrial development of large components for plasma exhaust pumping; Optimization of cryogenic vacuum pumping of helium; Plasma exhaust purification by means of cryosorption on molecular-sieves or alternative absorbents and use of hot-metal getters; Adsorption of DT on heated metal beds other than uranium; Catalyst development for the exhaust purification process; Development of ECRH power sources. NET study contracts: Availability of the LCT plant; Investigation of the vacuum and exhaust performation of NET; Study about the NET TF pancake test; Evaluation of crack growth delay in multilayer sheets. (orig./AH)

Advanced Nuclear Applications in Medicinr at Chiang Mai University

International Nuclear Information System (INIS)

Vilasdechanon, Nonglak

2015-01-01

The atomic energy applications in Faculty of Medicine, Chiang Mai University (CMU) are mainly performed by department of Radiology that is divided into three dicisions: 1) Diagnostic Radiology Division for the applications of X-rays, ultrasound, and magnetic resonance, 2) Therapeutic Radiology and Oncology Division for cancer treatments by photon accelrator and external radionuclides therapy or brachytherapy, 3) Nuclear Meddicine Division for clinical dignosis by using radionuclide scintigraphy, targeted molecular imaging and internal radionuclide therapy. In the last decade, many advanced medical images for clinical diagnosis included of digital & computed radiology (DR & CR), digital subtraction angiography (DSA) and images (DSI), computed tomography (CT) with dual X-rays energies, manetic resonance imaging (MRI), and hybrid images of SPECT/CT were established in Radiology Department and PET/CT Cyclitron Center Chiang Mai University (PCCMU), respectively. For cancer treatments, the frontier technologies in radiation oncligy therapy such as tomotherapy, IMRT, 3D conformal radiation treatment, stereotactic radiationtherapy (SRT), stereotactic radiation surgery (SRS), and radiation biology laboratory were implemented in the department as well. As far as fast development of nuclear technology in medicine, future implementation of advanced nuclear applications in medicine strongly need an intergrated knoowledge from many specialties e.g. computer softeare in image reconstruction, accuracy and and precision technology, production of specific radiotracers for molecular imaging and therapy, techniques in radionuclide productions, innovation of new wquipment or materials for radiationprotection and safety, etc. However the most important factors of nuclear applications in medicine are the vision, mission and the value statements of the organization on the high cost in radiology investment and human resources development. We have to emphasize that people who are involved

Mindfulness-based and acceptance-based interventions in sport and performance contexts.

Science.gov (United States)

Gardner, Frank L; Moore, Zella E

2017-08-01

Since mindfulness-based and acceptance-based practice models were first conceptualized and applied in sport in an attempt to enhance performance and overall well-being of athletes and performers, these state-of-the-art theoretical and practice models have substantially broadened our knowledge base and have been successfully incorporated into sport and performance practice domains worldwide. Evolving from a sound empirical foundation, mindfulness-based and acceptance-based models in sport psychology have accumulated a strong basic and applied empirical foundation. In the nearly 20 years since their incorporation in the context of sport, empirical findings have demonstrated efficacious outcomes associated with performance and personal well-being, as well as supported their theorized mechanisms of change. Particularly as sport and performance environments increasingly call upon practitioners to provide more comprehensive care to clientele, including a range of care from performance enhancement and maintenance, to general personal well-being, to subclinical and clinical issues, mindfulness-based and acceptance-based practitioners have the tools to offer robust, empirically informed interventions that can enhance skills and quality of life, and/or ameliorate personal struggles. Copyright © 2017 Elsevier Ltd. All rights reserved.

VO2-based radiative thermal transistor with a semi-transparent base

Science.gov (United States)

Prod'homme, Hugo; Ordonez-Miranda, Jose; Ezzahri, Younès; Drévillon, Jérémie; Joulain, Karl

2018-05-01

We study a radiative thermal transistor analogous to an electronic one made of a VO2 base placed between two silica semi-infinite plates playing the roles of the transistor collector and emitter. The fact that VO2 exhibits an insulator to metal transition is exploited to modulate and/or amplify heat fluxes between the emitter and the collector, by applying a thermal current on the VO2 base. We extend the work of precedent studies considering the case where the base can be semi-transparent so that heat can be exchanged directly between the collector and the emitter. Both near and far field cases are considered leading to 4 typical regimes resulting from the fact that the emitter-base and base-collector separation distances can be larger or smaller than the thermal wavelength for a VO2 layer opaque or semi-transparent. Thermal currents variations with the base temperatures are calculated and analyzed. It is found that the transistor can operate in an amplification mode as already stated in [1] or in a switching mode as seen in [2]. An optimum configuration for the base thickness and separation distance maximizing the thermal transistor modulation factor is found.

Facilitators' perceptions of problem-based learning and community-based education

Directory of Open Access Journals (Sweden)

Annali E Fichardt

2000-10-01

Full Text Available In 1997 the School for Nursing, University of the Orange Free State, changed from the traditional lecture method of teaching to problem-based learning and from a curative to a community-based approach. Lecturers from a traditional environment became facilitators and new skills such as listening, dialogue, negotiation, counselling and problemsolving were expected from them. Besides the role change, the environment changed from a structural classroom to an unstructured community. The aim of this research was to determine the perceptions and experiences of facilitators in problem-based learning and community-base education. *Please note: This is a reduced version of the abstract. Please refer to PDF for full text.

Frame-based safety analysis approach for decision-based errors

International Nuclear Information System (INIS)

Fan, Chin-Feng; Yihb, Swu

1997-01-01

A frame-based approach is proposed to analyze decision-based errors made by automatic controllers or human operators due to erroneous reference frames. An integrated framework, Two Frame Model (TFM), is first proposed to model the dynamic interaction between the physical process and the decision-making process. Two important issues, consistency and competing processes, are raised. Consistency between the physical and logic frames makes a TFM-based system work properly. Loss of consistency refers to the failure mode that the logic frame does not accurately reflect the state of the controlled processes. Once such failure occurs, hazards may arise. Among potential hazards, the competing effect between the controller and the controlled process is the most severe one, which may jeopardize a defense-in-depth design. When the logic and physical frames are inconsistent, conventional safety analysis techniques are inadequate. We propose Frame-based Fault Tree; Analysis (FFTA) and Frame-based Event Tree Analysis (FETA) under TFM to deduce the context for decision errors and to separately generate the evolution of the logical frame as opposed to that of the physical frame. This multi-dimensional analysis approach, different from the conventional correctness-centred approach, provides a panoramic view in scenario generation. Case studies using the proposed techniques are also given to demonstrate their usage and feasibility

From conventional software based systems to knowledge based systems

International Nuclear Information System (INIS)

Bologna, S.

1995-01-01

Even if todays nuclear power plants have a very good safety record, there is a continuous search for still improving safety. One direction of this effort address operational safety, trying to improve the handling of disturbances and accidents partly by further automation, partly by creating a better control room environment, providing the operator with intelligent support systems to help in the decision making process. Introduction of intelligent computerised operator support systems has proved to be an efficient way of improving the operators performance. A number of systems have been developed worldwide, assisting in tasks like process fault detection and diagnosis, selection and implementation of proper remedial actions. Unfortunately, the use of Knowledge Based Systems (KBSs), introduces a new dimension to the problem of the licensing process. KBSs, despite the different technology employed, are still nothing more than a computer program. Unfortunately, quite a few people building knowledge based systems seem to ignore the many good programming practices that have evolved over the years for producing traditional computer programs. In this paper the author will try to point out similarities and differences between conventional software based systems, and knowledge based systems, introducing also the concept of model based reasoning. (orig.) (25 refs., 2 figs.)

Case-based reasoning

CERN Document Server

Kolodner, Janet

1993-01-01

Case-based reasoning is one of the fastest growing areas in the field of knowledge-based systems and this book, authored by a leader in the field, is the first comprehensive text on the subject. Case-based reasoning systems are systems that store information about situations in their memory. As new problems arise, similar situations are searched out to help solve these problems. Problems are understood and inferences are made by finding the closest cases in memory, comparing and contrasting the problem with those cases, making inferences based on those comparisons, and asking questions whe

Lotus Base

DEFF Research Database (Denmark)

Mun, Terry; Bachmann, Asger; Gupta, Vikas

2016-01-01

exploration of Lotus genomic and transcriptomic data. Equally important are user-friendly in-browser tools designed for data visualization and interpretation. Here, we present Lotus Base, which opens to the research community a large, established LORE1 insertion mutant population containing an excess of 120...... such data, allowing users to construct, visualize, and annotate co-expression gene networks. Lotus Base takes advantage of modern advances in browser technology to deliver powerful data interpretation for biologists. Its modular construction and publicly available application programming interface enable...... developers to tap into the wealth of integrated Lotus data. Lotus Base is freely accessible at: https://lotus.au.dk....

Three dimensional pattern recognition using feature-based indexing and rule-based search

Science.gov (United States)

Lee, Jae-Kyu

In flexible automated manufacturing, robots can perform routine operations as well as recover from atypical events, provided that process-relevant information is available to the robot controller. Real time vision is among the most versatile sensing tools, yet the reliability of machine-based scene interpretation can be questionable. The effort described here is focused on the development of machine-based vision methods to support autonomous nuclear fuel manufacturing operations in hot cells. This thesis presents a method to efficiently recognize 3D objects from 2D images based on feature-based indexing. Object recognition is the identification of correspondences between parts of a current scene and stored views of known objects, using chains of segments or indexing vectors. To create indexed object models, characteristic model image features are extracted during preprocessing. Feature vectors representing model object contours are acquired from several points of view around each object and stored. Recognition is the process of matching stored views with features or patterns detected in a test scene. Two sets of algorithms were developed, one for preprocessing and indexed database creation, and one for pattern searching and matching during recognition. At recognition time, those indexing vectors with the highest match probability are retrieved from the model image database, using a nearest neighbor search algorithm. The nearest neighbor search predicts the best possible match candidates. Extended searches are guided by a search strategy that employs knowledge-base (KB) selection criteria. The knowledge-based system simplifies the recognition process and minimizes the number of iterations and memory usage. Novel contributions include the use of a feature-based indexing data structure together with a knowledge base. Both components improve the efficiency of the recognition process by improved structuring of the database of object features and reducing data base size

NSCT BASED LOCAL ENHANCEMENT FOR ACTIVE CONTOUR BASED IMAGE SEGMENTATION APPLICATION

Directory of Open Access Journals (Sweden)

Hiren Mewada

2010-08-01

Full Text Available Because of cross-disciplinary nature, Active Contour modeling techniques have been utilized extensively for the image segmentation. In traditional active contour based segmentation techniques based on level set methods, the energy functions are defined based on the intensity gradient. This makes them highly sensitive to the situation where the underlying image content is characterized by image nonhomogeneities due to illumination and contrast condition. This is the most difficult problem to make them as fully automatic image segmentation techniques. This paper introduces one of the approaches based on image enhancement to this problem. The enhanced image is obtained using NonSubsampled Contourlet Transform, which improves the edges strengths in the direction where the illumination is not proper and then active contour model based on level set technique is utilized to segment the object. Experiment results demonstrate that proposed method can be utilized along with existing active contour model based segmentation method under situation characterized by intensity non-homogeneity to make them fully automatic.

Data base EQDB - data base of the qualified equipment's for NPP

International Nuclear Information System (INIS)

Rovny, K.

2009-01-01

In the contribution, there is presented the project of the data base for qualified equipment's for nuclear power plants. The data base is operated by the 'Certification body which certified the products - the chosen equipment's for nuclear power plants', reg. No. P-028, at VUJE, Inc. Trnava. Data base will serve to the designers, the operators of the nuclear power plants and the workers from Nuclear regulatory authority of the Slovak Republic as a source of information about the state of concrete type equipment's qualification. In the first part of the contribution, there is information about the legislation and technical requirements for equipment's qualification, the way of demonstration and importance of the qualification for the operator. In the next part, there is presented the own structure of data base and the works with own data base regarding the examples of concrete equipment's. The data base will be accessible after the free registration on address WWW.EQDB.sk from 1.5.2009

Evidence-based radiography

International Nuclear Information System (INIS)

Hafslund, Bjorg; Clare, Judith; Graverholt, Birgitte; Wammen Nortvedt, Monica

2008-01-01

Evidence-based practice (EBP) offers the integration of the best research evidence with clinical knowledge and expertise and patient values. EBP is a well known term in health care. This paper discusses the implementation of EBP into radiography and introduces the term evidence-based radiography. Evidence-based radiography is radiography informed and based on the combination of clinical expertise and the best available research-based evidence, patient preferences and resources available. In Norway, EBP in radiography is being debated and radiographers are discussing the challenges of implementing EBP in both academic and clinical practice. This discussion paper explains why EBP needs to be a basis for a radiography curriculum and a part of radiographers' practice. We argue that Norwegian radiographers must increase participation in research and developing practice within their specific radiographic domain

Competency-Based Teaching in Radiology - Implementation and Evaluation of Interactive Workstation-Based Learning to Apply NKLM-Based Content.

Science.gov (United States)

Koestner, Wolfgang; Otten, Wiebke; Kaireit, Till; Wacker, Frank K; Dettmer, Sabine

2017-11-01

Purpose  New teaching formats are required to implement competency-based teaching in radiology teaching. Therefore, we have established and evaluated two practical competency-based radiological courses. Materials and Methods  The courses were held in a multimedia room with 25 computers and a professional DICOM viewer. Students were taught basic image analysis and presented clinical cases with a DICOM viewer under supervision of an instructor using desktop monitoring software. Two courses (elective course and obligatory course) were evaluated by the students (n = 160 and n = 100) and instructors (n = 9) using an anonymized online survey. Results  Courses were evaluated positively by the students and instructors. From the perspective of the students, the courses increased understanding of cross-sectional anatomy (elective/obligatory course: 97 %/95 %) and radiologic findings (97 %/99 %). Furthermore, the course increased the students' interest in radiology (61 %/65 %). The students considered this way of teaching to be relevant to their future occupation (92 % of students in the obligatory course). The higher incidence of teacher-student interaction and the possibility of independent image analysis were rated positively. The majority of instructors did not observe increased distractibility due to the computers (67 %) or notice worse preparation for MC tests (56 %). However, 56 % of instructors reported greater preparation effort. Conclusion  Practical competency-based radiological teaching using a DICOM viewer is a feasible innovative approach with high acceptance among students and instructors. It fosters competency-based learning as proposed by the model curriculum of the German Radiological Society (DRG) and the National Competency-based Catalogue of Learning Objectives for Undergraduate Medical Education (NKLM). Key Points   · Practical competency-based radiological teaching is highly accepted by students and instructors

Cultural and Rhetorical Bases for communicating knowledge in web based communities

DEFF Research Database (Denmark)

Kampf, Constance; Kommers, Piet

2008-01-01

Cultural and Rhetorical Bases for communicating knowledge in web based communities How can we extend learner-centred theories for educational technology to include, for instance, the cultural and rhetorical backgrounds which influence participants in online communities as they engage in knowledge...... via web-based communities the intersection of culture and rhetoric in web-based communication rhetoric and discourse in the process of communicating knowledge via technology heuristics for knowledge communication from teaching in online forums connections between identity and knowledge communication...... This call for papers invites papers focused on theoretical frameworks or empirical research which highlights the cultural and/or rhetorical aspects of communicating knowledge in web based communities. We are looking for work that brings together methods and perspectives across disciplines...

Characteristics Data Base: Programmer's guide to the High-Level Waste Data Base

International Nuclear Information System (INIS)

Jones, K.E.; Salmon, R.

1990-08-01

The High-Level Waste Data Base is a menu-driven PC data base developed as part of OCRWM's technical data base on the characteristics of potential repository wastes, which also includes spent fuel and other materials. This programmer's guide completes the documentation for the High-Level Waste Data Base, the user's guide having been published previously. 3 figs

An Alternative Collaborative Supervision Practice between University-Based Teachers and School-Based Teachers

Science.gov (United States)

Steele, Annfrid R.

2017-01-01

There is an increased focus in teacher education on research-based teaching as a means to develop a more research-based professional knowledge. However, research from several Western countries shows that neither school-based nor university-based teachers are familiar with how to integrate research-based knowledge in professional teacher practice.…

Paper based electronics platform

KAUST Repository

Nassar, Joanna Mohammad; Sevilla, Galo Andres Torres; Hussain, Muhammad Mustafa

2017-01-01

A flexible and non-functionalized low cost paper-based electronic system platform fabricated from common paper, such as paper based sensors, and methods of producing paper based sensors, and methods of sensing using the paper based sensors

Cholinesterase-based biosensors.

Science.gov (United States)

Štěpánková, Šárka; Vorčáková, Katarína

2016-01-01

Recently, cholinesterase-based biosensors are widely used for assaying anticholinergic compounds. Primarily biosensors based on enzyme inhibition are useful analytical tools for fast screening of inhibitors, such as organophosphates and carbamates. The present review is aimed at compilation of the most important facts about cholinesterase based biosensors, types of physico-chemical transduction, immobilization strategies and practical applications.

Strengths-based Learning

DEFF Research Database (Denmark)

Ledertoug, Mette Marie

-being. The Ph.D.-project in Strength-based learning took place in a Danish school with 750 pupils age 6-16 and a similar school was functioning as a control group. The presentation will focus on both the aware-explore-apply processes and the practical implications for the schools involved, and on measurable......Strength-based learning - Children͛s Character Strengths as Means to their Learning Potential͛ is a Ph.D.-project aiming to create a strength-based mindset in school settings and at the same time introducing strength-based interventions as specific tools to improve both learning and well...

Using Web-Based Peer Benchmarking to Manage the Client-Based Project

Science.gov (United States)

Raska, David; Keller, Eileen Weisenbach; Shaw, Doris

2013-01-01

The complexities of integrating client-based projects into marketing courses provide challenges for the instructor but produce richness of context and active learning for the student. This paper explains the integration of Web-based peer benchmarking as a means of improving student performance on client-based projects within a single semester in…

Novel nonlinear knowledge-based mean force potentials based on machine learning.

Science.gov (United States)

Dong, Qiwen; Zhou, Shuigeng

2011-01-01

The prediction of 3D structures of proteins from amino acid sequences is one of the most challenging problems in molecular biology. An essential task for solving this problem with coarse-grained models is to deduce effective interaction potentials. The development and evaluation of new energy functions is critical to accurately modeling the properties of biological macromolecules. Knowledge-based mean force potentials are derived from statistical analysis of proteins of known structures. Current knowledge-based potentials are almost in the form of weighted linear sum of interaction pairs. In this study, a class of novel nonlinear knowledge-based mean force potentials is presented. The potential parameters are obtained by nonlinear classifiers, instead of relative frequencies of interaction pairs against a reference state or linear classifiers. The support vector machine is used to derive the potential parameters on data sets that contain both native structures and decoy structures. Five knowledge-based mean force Boltzmann-based or linear potentials are introduced and their corresponding nonlinear potentials are implemented. They are the DIH potential (single-body residue-level Boltzmann-based potential), the DFIRE-SCM potential (two-body residue-level Boltzmann-based potential), the FS potential (two-body atom-level Boltzmann-based potential), the HR potential (two-body residue-level linear potential), and the T32S3 potential (two-body atom-level linear potential). Experiments are performed on well-established decoy sets, including the LKF data set, the CASP7 data set, and the Decoys “R”Us data set. The evaluation metrics include the energy Z score and the ability of each potential to discriminate native structures from a set of decoy structures. Experimental results show that all nonlinear potentials significantly outperform the corresponding Boltzmann-based or linear potentials, and the proposed discriminative framework is effective in developing knowledge-based

Using bio-based polymers for curing cement-based materials

NARCIS (Netherlands)

Zlopasa, J.; Koenders, E.A.B.; Picken, S.J.

2014-01-01

Curing is the process of controlling the rate and extent of moisture loss from the surface of cement based materials. It is the final stage in the production of cement-based materials and it is the essential part for achieving continuous hydration of cement, while avoiding cracking due to drying

Carbon-based sputtered coatings for enhanced chitosan-based films properties

Science.gov (United States)

Fernandes, C.; Calderon V., S.; Ballesteros, Lina F.; Cerqueira, Miguel A.; Pastrana, L. M.; Teixeira, José A.; Ferreira, P. J.; Carvalho, S.

2018-03-01

In order to make bio-based packaging materials competitive in comparison to petroleum-based one, some of their properties need to be improved, among which gas permeability is of crucial importance. Thus, in this work, carbon-based coatings were applied on chitosan-based films by radiofrequency reactive magnetron sputtering aiming to improve their barrier properties. Chemical and morphological properties were evaluated in order to determine the effect of the coatings on the chemical structure, surface hydrophobicity and barrier properties of the system. Chemical analysis, performed by electron energy loss spectroscopy and Fourier transform infrared spectroscopy, suggests similar chemical characteristics among all coatings although higher incorporation of hydrogen as the acetylene flux increases was observed. On the other hand, scanning transmission electron microscopy revealed that the porosity of the carbon layer can be tailored by the acetylene flux. More importantly, the chitosan oxygen permeability showed a monotonic reduction as a function of the acetylene flux. This study opens up new opportunities to apply nanostructured coatings on bio-based polymer for enhanced oxygen barrier properties.

Computer-based teaching is as good as face to face lecture-based teaching of evidence based medicine: a randomised controlled trial

Science.gov (United States)

2007-01-01

Background At postgraduate level evidence based medicine (EBM) is currently taught through tutor based lectures. Computer based sessions fit around doctors' workloads, and standardise the quality of educational provision. There have been no randomized controlled trials comparing computer based sessions with traditional lectures at postgraduate level within medicine. Methods This was a randomised controlled trial involving six postgraduate education centres in the West Midlands, U.K. Fifty five newly qualified foundation year one doctors (U.S internship equivalent) were randomised to either computer based sessions or an equivalent lecture in EBM and systematic reviews. The change from pre to post-intervention score was measured using a validated questionnaire assessing knowledge (primary outcome) and attitudes (secondary outcome). Results Both groups were similar at baseline. Participants' improvement in knowledge in the computer based group was equivalent to the lecture based group (gain in score: 2.1 [S.D = 2.0] versus 1.9 [S.D = 2.4]; ANCOVA p = 0.078). Attitudinal gains were similar in both groups. Conclusion On the basis of our findings we feel computer based teaching and learning is as effective as typical lecture based teaching sessions for educating postgraduates in EBM and systematic reviews. PMID:17659076

A model-based framework for design of intensified enzyme-based processes

DEFF Research Database (Denmark)

Román-Martinez, Alicia

This thesis presents a generic and systematic model-based framework to design intensified enzyme-based processes. The development of the presented methodology was motivated by the needs of the bio-based industry for a more systematic approach to achieve intensification in its production plants...... in enzyme-based processes which have found significant application in the pharmaceutical, food, and renewable fuels sector. The framework uses model-based strategies for (bio)-chemical process design and optimization, including the use of a superstructure to generate all potential reaction......(s)-separation(s) options according to a desired performance criteria and a generic mathematical model represented by the superstructure to derive the specific models corresponding to a specific process option. In principle, three methods of intensification of bioprocess are considered in this thesis: 1. enzymatic one...

Stolen Base Physics

Science.gov (United States)

Kagan, David

2013-01-01

Few plays in baseball are as consistently close and exciting as the stolen base. While there are several studies of sprinting, the art of base stealing is much more nuanced. This article describes the motion of the base-stealing runner using a very basic kinematic model. The model will be compared to some data from a Major League game. The…