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.
Mezher, Ahmad Mohamad; Igartua, Mónica Aguilar; de la Cruz Llopis, Luis J.; Segarra, Esteve Pallarès; Tripp-Barba, Carolina; Urquiza-Aguiar, Luis; Forné, Jordi; Gargallo, Emilio Sanvicente
2015-01-01
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. PMID:25897496
Organization model for Mobile Wireless Sensor Networks inspired in Artificial Bee Colony
NASA Astrophysics Data System (ADS)
Freire Roberto, Guilherme; Castilho Maschi, Luis Fernando; Pigatto, Daniel Fernando; Jaquie Castelo Branco, Kalinka Regina Lucas; Alves Neves, Leandro; Montez, Carlos; Sandro Roschildt Pinto, Alex
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).
Verifying Safety Messages Using Relative-Time and Zone Priority in Vehicular Ad Hoc Networks.
Banani, Sam; Gordon, Steven; Thiemjarus, Surapa; Kittipiyakul, Somsak
2018-04-13
In high-density road networks, with each vehicle broadcasting multiple messages per second, the arrival rate of safety messages can easily exceed the rate at which digital signatures can be verified. Since not all messages can be verified, algorithms for selecting which messages to verify are required to ensure that each vehicle receives appropriate awareness about neighbouring vehicles. This paper presents a novel scheme to select important safety messages for verification in vehicular ad hoc networks (VANETs). The proposed scheme uses location and direction of the sender, as well as proximity and relative-time between vehicles, to reduce the number of irrelevant messages verified (i.e., messages from vehicles that are unlikely to cause an accident). Compared with other existing schemes, the analysis results show that the proposed scheme can verify messages from nearby vehicles with lower inter-message delay and reduced packet loss and thus provides high level of awareness of the nearby vehicles.
Verifying Safety Messages Using Relative-Time and Zone Priority in Vehicular Ad Hoc Networks
Banani, Sam; Thiemjarus, Surapa; Kittipiyakul, Somsak
2018-01-01
In high-density road networks, with each vehicle broadcasting multiple messages per second, the arrival rate of safety messages can easily exceed the rate at which digital signatures can be verified. Since not all messages can be verified, algorithms for selecting which messages to verify are required to ensure that each vehicle receives appropriate awareness about neighbouring vehicles. This paper presents a novel scheme to select important safety messages for verification in vehicular ad hoc networks (VANETs). The proposed scheme uses location and direction of the sender, as well as proximity and relative-time between vehicles, to reduce the number of irrelevant messages verified (i.e., messages from vehicles that are unlikely to cause an accident). Compared with other existing schemes, the analysis results show that the proposed scheme can verify messages from nearby vehicles with lower inter-message delay and reduced packet loss and thus provides high level of awareness of the nearby vehicles. PMID:29652840
Decentralized session initiation protocol solution in ad hoc networks
NASA Astrophysics Data System (ADS)
Han, Lu; Jin, Zhigang; Shu, Yantai; Dong, Linfang
2006-10-01
With the fast development of ad hoc networks, SIP has attracted more and more attention in multimedia service. This paper proposes a new architecture to provide SIP service for ad hoc users, although there is no centralized SIP server deployed. In this solution, we provide the SIP service by the introduction of two nodes: Designated SIP Server (DS) and its Backup Server (BDS). The nodes of ad hoc network designate DS and BDS when they join the session nodes set and when some pre-defined events occur. A new sip message type called REGISTRAR is presented so nodes can send others REGISTRAR message to declare they want to be DS. According to the IP information taken in the message, an algorithm works like the election of DR and BDR in OSPF protocol is used to vote DS and BDS SIP servers. Naturally, the DS will be replaced by BDS when the DS is down for predicable or unpredictable reasons. To facilitate this, the DS should register to the BDS and transfer a backup of the SIP users' database. Considering the possibility DS or BDS may abruptly go down, a special policy is given. When there is no DS and BDS, a new election procedure is triggered just like the startup phase. The paper also describes how SIP works normally in the decentralized model as well as the evaluation of its performance. All sessions based on SIP in ad hoc such as DS voting have been tested in the real experiments within a 500m*500m square area where about 30 random nodes are placed.
A Group Based Key Sharing and Management Algorithm for Vehicular Ad Hoc Networks
Moharram, Mohammed Morsi; Azam, Farzana
2014-01-01
Vehicular ad hoc networks (VANETs) are one special type of ad hoc networks that involves vehicles on roads. Typically like ad hoc networks, broadcast approach is used for data dissemination. Blind broadcast to each and every node results in exchange of useless and irrelevant messages and hence creates an overhead. Unicasting is not preferred in ad-hoc networks due to the dynamic topology and the resource requirements as compared to broadcasting. Simple broadcasting techniques create several problems on privacy, disturbance, and resource utilization. In this paper, we propose media mixing algorithm to decide what information should be provided to each user and how to provide such information. Results obtained through simulation show that fewer number of keys are needed to share compared to simple broadcasting. Privacy is also enhanced through this approach. PMID:24587749
DOT National Transportation Integrated Search
2009-08-31
Primary research focused on the design and development of an energy-efficient Risk Notification Message Dissemination Protocol (RNMDP) for vehicular ad hoc networks (VANETs). RNMDP propagates Risk Notification Messages (RNMs) from a location of origi...
Cross-Layer Service Discovery Mechanism for OLSRv2 Mobile Ad Hoc Networks.
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.
Cross-Layer Service Discovery Mechanism for OLSRv2 Mobile Ad Hoc Networks
Vara, M. Isabel; Campo, Celeste
2015-01-01
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. PMID:26205272
The Effects of Drug-Prevention Messages on the Accessibility of Identity-Related Constructs
COMELLO, MARIA LEONORA G.; SLATER, MICHAEL D.
2011-01-01
Recent theoretical work has posited that the self-system guides behavior via currently activated self-concepts. We adopt this framework to the study of drug-prevention messages by examining the extent to which messages can alter the accessibility of views of self and of drugs that would support non-use. Participants were exposed to one of three print-ad conditions: autonomy-themed prevention messages (treatment), health-information themed prevention messages (comparison), and informational consumer ads (control). Outcomes were reaction times to make dichotomous judgments. Relative to comparison and control ads, treatment ads were more successful at activating a self-view as a nonuser, a view that marijuana use is inconsistent with autonomy, and unwillingness to use marijuana. Post-hoc analysis revealed that the effect of ad condition on unwillingness was partially mediated by the accessibility of self-view as a nonuser. PMID:21271426
SPECS: Secure and Privacy Enhancing Communications Schemes for VANETs
NASA Astrophysics Data System (ADS)
Chim, T. W.; Yiu, S. M.; Hui, L. C. K.; Jiang, Zoe L.; Li, Victor O. K.
Vehicular ad hoc network (VANET) is an emerging type of networks which facilitates vehicles on roads to communicate for driving safety. The basic idea is to allow arbitrary vehicles to broadcast ad hoc messages (e.g. traffic accidents) to other vehicles. However, this raises the concern of security and privacy. Messages should be signed and verified before they are trusted while the real identity of vehicles should not be revealed, but traceable by authorized party. Existing solutions either rely heavily on a tamper-proof hardware device, or cannot satisfy the privacy requirement and do not have an effective message verification scheme. In this paper, we provide a software-based solution which makes use of only two shared secrets to satisfy the privacy requirement and gives lower message overhead and at least 45% higher successful rate than previous solutions in the message verification phase using the bloom filter and the binary search techniques. We also provide the first group communication protocol to allow vehicles to authenticate and securely communicate with others in a group of known vehicles.
The effects of malicious nodes on performance of mobile ad hoc networks
NASA Astrophysics Data System (ADS)
Li, Fanzhi; Shi, Xiyu; Jassim, Sabah; Adams, Christopher
2006-05-01
Wireless ad hoc networking offers convenient infrastructureless communication over the shared wireless channel. However, the nature of ad hoc networks makes them vulnerable to security attacks. Unlike their wired counterpart, infrastructureless ad hoc networks do not have a clear line of defense, their topology is dynamically changing, and every mobile node can receive messages from its neighbors and can be contacted by all other nodes in its neighborhood. This poses a great danger to network security if some nodes behave in a malicious manner. The immediate concern about the security in this type of networks is how to protect the network and the individual mobile nodes against malicious act of rogue nodes from within the network. This paper is concerned with security aspects of wireless ad hoc networks. We shall present results of simulation experiments on ad hoc network's performance in the presence of malicious nodes. We shall investigate two types of attacks and the consequences will be simulated and quantified in terms of loss of packets and other factors. The results show that network performance, in terms of successful packet delivery ratios, significantly deteriorates when malicious nodes act according to the defined misbehaving characteristics.
Integrated data lookup and replication scheme in mobile ad hoc networks
NASA Astrophysics Data System (ADS)
Chen, Kai; Nahrstedt, Klara
2001-11-01
Accessing remote data is a challenging task in mobile ad hoc networks. Two problems have to be solved: (1) how to learn about available data in the network; and (2) how to access desired data even when the original copy of the data is unreachable. In this paper, we develop an integrated data lookup and replication scheme to solve these problems. In our scheme, a group of mobile nodes collectively host a set of data to improve data accessibility for all members of the group. They exchange data availability information by broadcasting advertising (ad) messages to the group using an adaptive sending rate policy. The ad messages are used by other nodes to derive a local data lookup table, and to reduce data redundancy within a connected group. Our data replication scheme predicts group partitioning based on each node's current location and movement patterns, and replicates data to other partitions before partitioning occurs. Our simulations show that data availability information can quickly propagate throughout the network, and that the successful data access ratio of each node is significantly improved.
NASA Astrophysics Data System (ADS)
Xin, Qin; Yao, Xiaolan; Engelstad, Paal E.
2010-09-01
Wireless Mesh Networking is an emerging communication paradigm to enable resilient, cost-efficient and reliable services for the future-generation wireless networks. We study here the minimum-latency communication primitive of gossiping (all-to-all communication) in multi-hop ad-hoc Wireless Mesh Networks (WMNs). Each mesh node in the WMN is initially given a message and the objective is to design a minimum-latency schedule such that each mesh node distributes its message to all other mesh nodes. Minimum-latency gossiping problem is well known to be NP-hard even for the scenario in which the topology of the WMN is known to all mesh nodes in advance. In this paper, we propose a new latency-efficient approximation scheme that can accomplish gossiping task in polynomial time units in any ad-hoc WMN under consideration of Large Interference Range (LIR), e.g., the interference range is much larger than the transmission range. To the best of our knowledge, it is first time to investigate such a scenario in ad-hoc WMNs under LIR, our algorithm allows the labels (e.g., identifiers) of the mesh nodes to be polynomially large in terms of the size of the WMN, which is the first time that the scenario of large labels has been considered in ad-hoc WMNs under LIR. Furthermore, our gossiping scheme can be considered as a framework which can be easily implied to the scenario under consideration of mobility-related issues since we assume that the mesh nodes have no knowledge on the network topology even for its neighboring mesh nodes.
2018-01-01
Vehicle ad hoc networks (VANETs) is a promising network scenario for greatly improving traffic efficiency and safety, in which smart vehicles can communicate with other vehicles or roadside units. For the availability of VANETs, it is very important to deal with the security and privacy problems for VANETs. In this paper, based on certificateless cryptography and elliptic curve cryptography, we present a certificateless signature with message recovery (CLS-MR), which we believe are of independent interest. Then, a practical certificateless conditional privacy preserving authentication (PCPA) scheme is proposed by incorporating the proposed CLS-MR scheme. Furthermore, the security analysis shows that PCPA satisfies all security and privacy requirements. The evaluation results indicate that PCPA achieves low computation and communication costs because there is no need to use the bilinear pairing and map-to-point hash operations. Moreover, extensive simulations show that PCPA is feasible and achieves prominent performances in terms of message delay and message loss ratio, and thus is more suitable for the deployment and adoption of VANETs. PMID:29762511
Scalability enhancement of AODV using local link repairing
NASA Astrophysics Data System (ADS)
Jain, Jyoti; Gupta, Roopam; Bandhopadhyay, T. K.
2014-09-01
Dynamic change in the topology of an ad hoc network makes it difficult to design an efficient routing protocol. Scalability of an ad hoc network is also one of the important criteria of research in this field. Most of the research works in ad hoc network focus on routing and medium access protocols and produce simulation results for limited-size networks. Ad hoc on-demand distance vector (AODV) is one of the best reactive routing protocols. In this article, modified routing protocols based on local link repairing of AODV are proposed. Method of finding alternate routes for next-to-next node is proposed in case of link failure. These protocols are beacon-less, means periodic hello message is removed from the basic AODV to improve scalability. Few control packet formats have been changed to accommodate suggested modification. Proposed protocols are simulated to investigate scalability performance and compared with basic AODV protocol. This also proves that local link repairing of proposed protocol improves scalability of the network. From simulation results, it is clear that scalability performance of routing protocol is improved because of link repairing method. We have tested protocols for different terrain area with approximate constant node densities and different traffic load.
Intelligent Traffic Quantification System
NASA Astrophysics Data System (ADS)
Mohanty, Anita; Bhanja, Urmila; Mahapatra, Sudipta
2017-08-01
Currently, city traffic monitoring and controlling is a big issue in almost all cities worldwide. Vehicular ad-hoc Network (VANET) technique is an efficient tool to minimize this problem. Usually, different types of on board sensors are installed in vehicles to generate messages characterized by different vehicle parameters. In this work, an intelligent system based on fuzzy clustering technique is developed to reduce the number of individual messages by extracting important features from the messages of a vehicle. Therefore, the proposed fuzzy clustering technique reduces the traffic load of the network. The technique also reduces congestion and quantifies congestion.
The Vehicular Information Space Framework
NASA Astrophysics Data System (ADS)
Prinz, Vivian; Schlichter, Johann; Schweiger, Benno
Vehicular networks are distributed, self-organizing and highly mobile ad hoc networks. They allow for providing drivers with up-to-the-minute information about their environment. Therefore, they are expected to be a decisive future enabler for enhancing driving comfort and safety. This article introduces the Vehicular Information Space framework (VIS). Vehicles running the VIS form a kind of distributed database. It enables them to provide information like existing hazards, parking spaces or traffic densities in a location aware and fully distributed manner. In addition, vehicles can retrieve, modify and delete these information items. The underlying algorithm is based on features derived from existing structured Peer-to-Peer algorithms and extended to suit the specific characteristics of highly mobile ad hoc networks. We present, implement and simulate the VIS using a motorway and an urban traffic environment. Simulation studies on VIS message occurrence show that the VIS implies reasonable traffic overhead. Also, overall VIS message traffic is independent from the number of information items provided.
Supporting Dynamic Ad hoc Collaboration Capabilities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Agarwal, Deborah A.; Berket, Karlo
2003-07-14
Modern HENP experiments such as CMS and Atlas involve as many as 2000 collaborators around the world. Collaborations this large will be unable to meet often enough to support working closely together. Many of the tools currently available for collaboration focus on heavy-weight applications such as videoconferencing tools. While these are important, there is a more basic need for tools that support connecting physicists to work together on an ad hoc or continuous basis. Tools that support the day-to-day connectivity and underlying needs of a group of collaborators are important for providing light-weight, non-intrusive, and flexible ways to work collaboratively.more » Some example tools include messaging, file-sharing, and shared plot viewers. An important component of the environment is a scalable underlying communication framework. In this paper we will describe our current progress on building a dynamic and ad hoc collaboration environment and our vision for its evolution into a HENP collaboration environment.« less
Design and Implementation of Secure Area Expansion Scheme for Public Wireless LAN Services
NASA Astrophysics Data System (ADS)
Watanabe, Ryu; Tanaka, Toshiaki
Recently, wireless LAN (WLAN) technology has become a major wireless communication method. The communication bandwidth is increasing and speeds have attained rates exceeding 100 Mbps. Therefore, WLAN technology is regarded as one of the promising communication methods for future networks. In addition, public WLAN connection services can be used in many locations. However, the number of the access points (AP) is insufficient for seamless communication and it cannot be said that users can use the service ubiquitously. An ad-hoc network style connection can be used to expand the coverage area of a public WLAN service. By relaying the user messages among the user nodes, a node can obtain an Internet connection via an AP, even though the node is located outside the AP's direct wireless connection area. Such a coverage area extending technology has many advantages thanks to the feature that no additional infrastructure is required. Therefore, there is a strong demand for this technology as it allows the cost-effective construction of future networks. When a secure ad-hoc routing protocol is used for message exchange in the WLAN service, the message routes are protected from malicious behavior such as route forging and can be maintained appropriately. To do this, however, a new node that wants to join the WLAN service has to obtain information such as the public key certificate and IP address in order to start secure ad-hoc routing. In other words, an initial setup is required for every network node to join the WLAN service properly. Ordinarily, such information should be assigned from the AP. However, new nodes cannot always contact an AP directly. Therefore, there are problems about information delivery in the initial setup of a network node. These problems originate in the multi hop connection based on the ad-hoc routing protocols. In order to realize an expanded area WLAN service, in this paper, the authors propose a secure public key certificate and address provision scheme during the initial setup phase on mobile nodes for the service. The proposed scheme also considers the protection of user privacy. Accordingly, none of the user nodes has to reveal their unique and persistent information to other nodes. Instead of using such information, temporary values are sent by an AP to mobile nodes and used for secure ad-hoc routing operations. Therefore, our proposed scheme prevents tracking by malicious parties by avoiding the use of unique information. Moreover, a test bed was also implemented based on the proposal and an evaluation was carried out in order to confirm performance. In addition, the authors describe a countermeasure against denial of service (DoS) attacks based on the approach to privacy protection described in our proposal.
A DNA-Inspired Encryption Methodology for Secure, Mobile Ad Hoc Networks
NASA Technical Reports Server (NTRS)
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.
Event-Driven Messaging for Offline Data Quality Monitoring at ATLAS
NASA Astrophysics Data System (ADS)
Onyisi, Peter
2015-12-01
During LHC Run 1, the information flow through the offline data quality monitoring in ATLAS relied heavily on chains of processes polling each other's outputs for handshaking purposes. This resulted in a fragile architecture with many possible points of failure and an inability to monitor the overall state of the distributed system. We report on the status of a project undertaken during the LHC shutdown to replace the ad hoc synchronization methods with a uniform message queue system. This enables the use of standard protocols to connect processes on multiple hosts; reliable transmission of messages between possibly unreliable programs; easy monitoring of the information flow; and the removal of inefficient polling-based communication.
Wireless Sensor Network Quality of Service Improvement on Flooding Attack Condition
NASA Astrophysics Data System (ADS)
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.
Location Privacy Protection on Social Networks
NASA Astrophysics Data System (ADS)
Zhan, Justin; Fang, Xing
Location information is considered as private in many scenarios. Protecting location information on mobile ad-hoc networks has attracted much research in past years. However, location information protection on social networks has not been paid much attention. In this paper, we present a novel location privacy protection approach on the basis of user messages in social networks. Our approach grants flexibility to users by offering them multiple protecting options. To the best of our knowledge, this is the first attempt to protect social network users' location information via text messages. We propose five algorithms for location privacy protection on social networks.
Performance Analysis of the IEEE 802.11p Multichannel MAC Protocol in Vehicular Ad Hoc Networks
2017-01-01
Vehicular Ad Hoc Networks (VANETs) employ multichannel to provide a variety of safety and non-safety applications, based on the IEEE 802.11p and IEEE 1609.4 protocols. The safety applications require timely and reliable transmissions, while the non-safety applications require efficient and high throughput. In the IEEE 1609.4 protocol, operating interval is divided into alternating Control Channel (CCH) interval and Service Channel (SCH) interval with an identical length. During the CCH interval, nodes transmit safety-related messages and control messages, and Enhanced Distributed Channel Access (EDCA) mechanism is employed to allow four Access Categories (ACs) within a station with different priorities according to their criticality for the vehicle’s safety. During the SCH interval, the non-safety massages are transmitted. An analytical model is proposed in this paper to evaluate performance, reliability and efficiency of the IEEE 802.11p and IEEE 1609.4 protocols. The proposed model improves the existing work by taking serval aspects and the character of multichannel switching into design consideration. Extensive performance evaluations based on analysis and simulation help to validate the accuracy of the proposed model and analyze the capabilities and limitations of the IEEE 802.11p and IEEE 1609.4 protocols, and enhancement suggestions are given. PMID:29231882
SVANET: A smart vehicular ad hoc network for efficient data transmission with wireless sensors.
Sahoo, Prasan Kumar; Chiang, Ming-Jer; Wu, Shih-Lin
2014-11-25
Wireless sensors can sense any event, such as accidents, as well as icy roads, and can forward the rescue/warning messages through intermediate vehicles for any necessary help. In this paper, we propose a smart vehicular ad hoc network (SVANET) architecture that uses wireless sensors to detect events and vehicles to transmit the safety and non-safety messages efficiently by using different service channels and one control channel with different priorities. We have developed a data transmission protocol for the vehicles in the highway, in which data can be forwarded with the help of vehicles if they are connected with each other or data can be forwarded with the help of nearby wireless sensors. Our data transmission protocol is designed to increase the driving safety, to prevent accidents and to utilize channels efficiently by adjusting the control and service channel time intervals dynamically. Besides, our protocol can transmit information to vehicles in advance, so that drivers can decide an alternate route in case of traffic congestion. For various data sharing, we design a method that can select a few leader nodes among vehicles running along a highway to broadcast data efficiently. Simulation results show that our protocol can outperform the existing standard in terms of the end to end packet delivery ratio and latency.
Performance Analysis of the IEEE 802.11p Multichannel MAC Protocol in Vehicular Ad Hoc Networks.
Song, Caixia
2017-12-12
Vehicular Ad Hoc Networks (VANETs) employ multichannel to provide a variety of safety and non-safety applications, based on the IEEE 802.11p and IEEE 1609.4 protocols. The safety applications require timely and reliable transmissions, while the non-safety applications require efficient and high throughput. In the IEEE 1609.4 protocol, operating interval is divided into alternating Control Channel (CCH) interval and Service Channel (SCH) interval with an identical length. During the CCH interval, nodes transmit safety-related messages and control messages, and Enhanced Distributed Channel Access (EDCA) mechanism is employed to allow four Access Categories (ACs) within a station with different priorities according to their criticality for the vehicle's safety. During the SCH interval, the non-safety massages are transmitted. An analytical model is proposed in this paper to evaluate performance, reliability and efficiency of the IEEE 802.11p and IEEE 1609.4 protocols. The proposed model improves the existing work by taking serval aspects and the character of multichannel switching into design consideration. Extensive performance evaluations based on analysis and simulation help to validate the accuracy of the proposed model and analyze the capabilities and limitations of the IEEE 802.11p and IEEE 1609.4 protocols, and enhancement suggestions are given.
SVANET: A Smart Vehicular Ad Hoc Network for Efficient Data Transmission with Wireless Sensors
Sahoo, Prasan Kumar; Chiang, Ming-Jer; Wu, Shih-Lin
2014-01-01
Wireless sensors can sense any event, such as accidents, as well as icy roads, and can forward the rescue/warning messages through intermediate vehicles for any necessary help. In this paper, we propose a smart vehicular ad hoc network (SVANET) architecture that uses wireless sensors to detect events and vehicles to transmit the safety and non-safety messages efficiently by using different service channels and one control channel with different priorities. We have developed a data transmission protocol for the vehicles in the highway, in which data can be forwarded with the help of vehicles if they are connected with each other or data can be forwarded with the help of nearby wireless sensors. Our data transmission protocol is designed to increase the driving safety, to prevent accidents and to utilize channels efficiently by adjusting the control and service channel time intervals dynamically. Besides, our protocol can transmit information to vehicles in advance, so that drivers can decide an alternate route in case of traffic congestion. For various data sharing, we design a method that can select a few leader nodes among vehicles running along a highway to broadcast data efficiently. Simulation results show that our protocol can outperform the existing standard in terms of the end to end packet delivery ratio and latency. PMID:25429409
Li, Peng; Huang, Chuanhe; Liu, Qin
2014-01-01
In vehicular ad hoc networks, roadside units (RSUs) placement has been proposed to improve the the overall network performance in many ITS applications. This paper addresses the budget constrained and delay-bounded placement problem (BCDP) for roadside units in vehicular ad hoc networks. There are two types of RSUs: cable connected RSU (c-RSU) and wireless RSU (w-RSU). c-RSUs are interconnected through wired lines, and they form the backbone of VANETs, while w-RSUs connect to other RSUs through wireless communication and serve as an economical extension of the coverage of c-RSUs. The delay-bounded coverage range and deployment cost of these two cases are totally different. We are given a budget constraint and a delay bound, the problem is how to find the optimal candidate sites with the maximal delay-bounded coverage to place RSUs such that a message from any c-RSU in the region can be disseminated to the more vehicles within the given budget constraint and delay bound. We first prove that the BCDP problem is NP-hard. Then we propose several algorithms to solve the BCDP problem. Simulation results show the heuristic algorithms can significantly improve the coverage range and reduce the total deployment cost, compared with other heuristic methods. PMID:25436656
ROSA: Distributed Joint Routing and Dynamic Spectrum Allocation in Cognitive Radio Ad Hoc Networks
2010-03-01
Aug. 1999. [20] I. N. Psaromiligkos and S. N. Batalama. Rapid Combined Synchronization/Demodulation Structures for DS - CDMA Systems - Part II: Finite...Medley. Rapid Combined Synchronization/Demodulation Structures for DS - CDMA Systems - Part I: Algorithmic developments. IEEE Transactions on...multiple access ( CDMA ) [21][20] al- low concurrent co-located communications so that a message from node i to node j can be correctly received even if
New Capabilities in Security and QoS Using the Updated MANET Routing Protocol OLSRv2
2010-09-01
integrity, by the authentication of packets or messages, and confidentiality. These are discussed in the following sections. Issues of availability...fully specified, in [2] is the addition of a TLV including a cryptographic signature that will allow the authentication of the received information...The objective is to ensure the integrity of the ad hoc network, that only authorised routers can join the network because unauthorised routers will
A native Bayesian classifier based routing protocol for VANETS
NASA Astrophysics Data System (ADS)
Bao, Zhenshan; Zhou, Keqin; Zhang, Wenbo; Gong, Xiaolei
2016-12-01
Geographic routing protocols are one of the most hot research areas in VANET (Vehicular Ad-hoc Network). However, there are few routing protocols can take both the transmission efficient and the usage of ratio into account. As we have noticed, different messages in VANET may ask different quality of service. So we raised a Native Bayesian Classifier based routing protocol (Naive Bayesian Classifier-Greedy, NBC-Greedy), which can classify and transmit different messages by its emergency degree. As a result, we can balance the transmission efficient and the usage of ratio with this protocol. Based on Matlab simulation, we can draw a conclusion that NBC-Greedy is more efficient and stable than LR-Greedy and GPSR.
Assessing Robustness Properties in Dynamic Discovery of Ad Hoc Network Services (Briefing Charts)
2001-10-04
JINI entities in directed -- discovery mode. It is part of the SCM_Discovery -- Module. Sends Unicast messages to SCMs on list of -- SCMS to be...discovered until all SCMS are found. -- Receives updates from SCM DB of discovered SCMs and -- removes SCMs accordingly -- NOTE: Failure and...For All (SM, SD, SCM ): (SM, SD) IsElementOf SCM registered-services (CC1) implies SCM IsElementOf SM discovered- SCMs For All
A communication theoretical analysis of FRET-based mobile ad hoc molecular nanonetworks.
Kuscu, Murat; Akan, Ozgur B
2014-09-01
Nanonetworks refer to a group of nanosized machines with very basic operational capabilities communicating to each other in order to accomplish more complex tasks such as in-body drug delivery, or chemical defense. Realizing reliable and high-rate communication between these nanomachines is a fundamental problem for the practicality of these nanonetworks. Recently, we have proposed a molecular communication method based on Förster Resonance Energy Transfer (FRET) which is a nonradiative excited state energy transfer phenomenon observed among fluorescent molecules, i.e., fluorophores. We have modeled the FRET-based communication channel considering the fluorophores as single-molecular immobile nanomachines, and shown its reliability at high rates, and practicality at the current stage of nanotechnology. In this study, for the first time in the literature, we investigate the network of mobile nanomachines communicating through FRET. We introduce two novel mobile molecular nanonetworks: FRET-based mobile molecular sensor/actor nanonetwork (FRET-MSAN) which is a distributed system of mobile fluorophores acting as sensor or actor node; and FRET-based mobile ad hoc molecular nanonetwork (FRET-MAMNET) which consists of fluorophore-based nanotransmitter, nanoreceivers and nanorelays. We model the single message propagation based on birth-death processes with continuous time Markov chains. We evaluate the performance of FRET-MSAN and FRET-MAMNET in terms of successful transmission probability and mean extinction time of the messages, system throughput, channel capacity and achievable communication rates.
Self-Organized Link State Aware Routing for Multiple Mobile Agents in Wireless Network
NASA Astrophysics Data System (ADS)
Oda, Akihiro; Nishi, Hiroaki
Recently, the importance of data sharing structures in autonomous distributed networks has been increasing. A wireless sensor network is used for managing distributed data. This type of distributed network requires effective information exchanging methods for data sharing. To reduce the traffic of broadcasted messages, reduction of the amount of redundant information is indispensable. In order to reduce packet loss in mobile ad-hoc networks, QoS-sensitive routing algorithm have been frequently discussed. The topology of a wireless network is likely to change frequently according to the movement of mobile nodes, radio disturbance, or fading due to the continuous changes in the environment. Therefore, a packet routing algorithm should guarantee QoS by using some quality indicators of the wireless network. In this paper, a novel information exchanging algorithm developed using a hash function and a Boolean operation is proposed. This algorithm achieves efficient information exchanges by reducing the overhead of broadcasting messages, and it can guarantee QoS in a wireless network environment. It can be applied to a routing algorithm in a mobile ad-hoc network. In the proposed routing algorithm, a routing table is constructed by using the received signal strength indicator (RSSI), and the neighborhood information is periodically broadcasted depending on this table. The proposed hash-based routing entry management by using an extended MAC address can eliminate the overhead of message flooding. An analysis of the collision of hash values contributes to the determination of the length of the hash values, which is minimally required. Based on the verification of a mathematical theory, an optimum hash function for determining the length of hash values can be given. Simulations are carried out to evaluate the effectiveness of the proposed algorithm and to validate the theory in a general wireless network routing algorithm.
Routing Based on Length of Time of Available Connection
NASA Technical Reports Server (NTRS)
Anandappan, Thanga (Inventor); Roy, Aloke (Inventor); Malve, Sharath Babu (Inventor); Toth, Louis T. (Inventor)
2016-01-01
In an embodiment, a method of routing packets at a first node in an ad-hoc network is provided. The method includes receiving, at the first node, a plurality of route-alive messages corresponding to a destination, each of the plurality of route-alive messages including a route time indicating a length of time in which a communicative connection is available between the second node that sent the respective route-alive message and the destination. The method also includes determining an updated route time for each second node. The updated route time corresponds to a length of time in which a communication connection is available between the first node and the destination through the respective second node. A second node is selected for sending a packet to based on the updated route time for each of the second nodes, wherein a node having a longer updated route time is given higher priority for selection.
2001-01-31
function of Jini, UPnP, SLP, Bluetooth , and HAVi • Projected specific UML models for Jini, UPnP, and SLP • Developed a Rapide Model of Jini...is used by all JINI entities in directed -- discovery mode. It is part of the SCM_Discovery -- Module. Sends Unicast messages to SCMs on list of... SCMS to be discovered until all SCMS are found. -- Receives updates from SCM DB of discovered SCMs and -- removes SCMs accordingly -- NOTE
Distributed Trust Evaluation in Ad-Hoc Networks
2004-01-01
of money that the issuer will pay to anyone who is misled because of the certificate. Being misled means falsely authenticating the certified entity...Alice to Bob. This is the minimum amount of money for which Alice is insured in the case of her being misled by Bob’s key. Note that if all edges are...confidence gets to vote first. Moreover, some paths are pruned which means that fewer messages are exchanged, thus saving bandwidth, but also some of the
A Family of ACO Routing Protocols for Mobile Ad Hoc Networks.
Rupérez Cañas, Delfín; Sandoval Orozco, Ana Lucila; García Villalba, Luis Javier; Kim, Tai-Hoon
2017-05-22
In this work, an ACO routing protocol for mobile ad hoc networks based on AntHocNet is specified. As its predecessor, this new protocol, called AntOR, is hybrid in the sense that it contains elements from both reactive and proactive routing. Specifically, it combines a reactive route setup process with a proactive route maintenance and improvement process. Key aspects of the AntOR protocol are the disjoint-link and disjoint-node routes, separation between the regular pheromone and the virtual pheromone in the diffusion process and the exploration of routes, taking into consideration the number of hops in the best routes. In this work, a family of ACO routing protocols based on AntOR is also specified. These protocols are based on protocol successive refinements. In this work, we also present a parallelized version of AntOR that we call PAntOR. Using programming multiprocessor architectures based on the shared memory protocol, PAntOR allows running tasks in parallel using threads. This parallelization is applicable in the route setup phase, route local repair process and link failure notification. In addition, a variant of PAntOR that consists of having more than one interface, which we call PAntOR-MI (PAntOR-Multiple Interface), is specified. This approach parallelizes the sending of broadcast messages by interface through threads.
A hierarchical detection method in external communication for self-driving vehicles based on TDMA.
Alheeti, Khattab M Ali; Al-Ani, Muzhir Shaban; McDonald-Maier, Klaus
2018-01-01
Security is considered a major challenge for self-driving and semi self-driving vehicles. These vehicles depend heavily on communications to predict and sense their external environment used in their motion. They use a type of ad hoc network termed Vehicular ad hoc networks (VANETs). Unfortunately, VANETs are potentially exposed to many attacks on network and application level. This paper, proposes a new intrusion detection system to protect the communication system of self-driving cars; utilising a combination of hierarchical models based on clusters and log parameters. This security system is designed to detect Sybil and Wormhole attacks in highway usage scenarios. It is based on clusters, utilising Time Division Multiple Access (TDMA) to overcome some of the obstacles of VANETs such as high density, high mobility and bandwidth limitations in exchanging messages. This makes the security system more efficient, accurate and capable of real time detection and quick in identification of malicious behaviour in VANETs. In this scheme, each vehicle log calculates and stores different parameter values after receiving the cooperative awareness messages from nearby vehicles. The vehicles exchange their log data and determine the difference between the parameters, which is utilised to detect Sybil attacks and Wormhole attacks. In order to realize efficient and effective intrusion detection system, we use the well-known network simulator (ns-2) to verify the performance of the security system. Simulation results indicate that the security system can achieve high detection rates and effectively detect anomalies with low rate of false alarms.
A Wi-Fi based Electronic Road Sign for Enhancing the Awareness of Vehicle Driver
NASA Astrophysics Data System (ADS)
Bhawiyuga, A.; Sabriansyah, R. A.; Yahya, W.; E Putra, R.
2017-01-01
Reducing the road accident rate is one of the city goal in the area of transportation. One of the effort to reach that goal is done by deploying various signs across the road. However, the role of those road signs can be diminished once the vehicle drivers intentionally or unintentionally disobey the rule indicated on those signs. In order to increase the awareness of the driver, we can employ the vehicular network concept in which a vehicle can communicate with another vehicles or with the infrastructure installed along the road. For realizing that idea, we propose the implementation of communication equipped road sign system which consists of two components: Road Side Unit (RSU) module deployed at road sign and On Board Unit (OBU) module deployed at each vehicle. In our proposed scheme, both of the devices communicate each other through the widely-used Wi-Fi protocol (IEEE 802.11n) operating in ad-hoc mode. While a OBU equipped vehicle is moving towards the communication range of RSU, it will make an association to a predefined wireless ad-hoc network. Once it is associated, the OBU can receive message broadcast by the RSU. Upon reception, OBU display alert message indicating that the vehicle is approaching a road sign. From performance testing we observe that the proposed system can give relatively good service the vehicle moving as fast as speed 90km/h with the distance as far as 90m.
Toyota, Toshiaki; Morimoto, Takeshi; Shiomi, Hiroki; Ando, Kenji; Ono, Koh; Shizuta, Satoshi; Kato, Takao; Saito, Naritatsu; Furukawa, Yutaka; Nakagawa, Yoshihisa; Horie, Minoru; Kimura, Takeshi
2017-03-24
Few studies have evaluated the prevalence and clinical outcomes of ad hoc percutaneous coronary intervention (PCI), performing diagnostic coronary angiography and PCI in the same session, in stable coronary artery disease (CAD) patients.Methods and Results:From the CREDO-Kyoto PCI/CABG registry cohort-2, 6,943 patients were analyzed as having stable CAD and undergoing first PCI. Ad hoc PCI and non-ad hoc PCI were performed in 1,722 (24.8%) and 5,221 (75.1%) patients, respectively. The cumulative 5-year incidence and adjusted risk for all-cause death were not significantly different between the 2 groups (15% vs. 15%, P=0.53; hazard ratio: 1.15, 95% confidence interval: 0.98-1.35, P=0.08). Ad hoc PCI relative to non-ad hoc PCI was associated with neutral risk for myocardial infarction, any coronary revascularization, and bleeding, but was associated with a trend towards lower risk for stroke (hazard ratio: 0.78, 95% confidence interval: 0.60-1.02, P=0.06). Ad hoc PCI in stable CAD patients was associated with at least comparable 5-year clinical outcomes as with non-ad hoc PCI. Considering patients' preference and the cost-saving, the ad hoc PCI strategy might be a safe and attractive option for patients with stable CAD, although the prevalence of ad hoc PCI was low in the current study population.
Vehicle Density Based Forwarding Protocol for Safety Message Broadcast in VANET
Huang, Jiawei; Wang, Jianxin
2014-01-01
In vehicular ad hoc networks (VANETs), the medium access control (MAC) protocol is of great importance to provide time-critical safety applications. Contemporary multihop broadcast protocols in VANETs usually choose the farthest node in broadcast range as the forwarder to reduce the number of forwarding hops. However, in this paper, we demonstrate that the farthest forwarder may experience large contention delay in case of high vehicle density. We propose an IEEE 802.11-based multihop broadcast protocol VDF to address the issue of emergency message dissemination. To achieve the tradeoff between contention delay and forwarding hops, VDF adaptably chooses the forwarder according to the vehicle density. Simulation results show that, due to its ability to decrease the transmission collisions, the proposed protocol can provide significantly lower broadcast delay. PMID:25121125
An Efficient and QoS Supported Multichannel MAC Protocol for Vehicular Ad Hoc Networks
Tan, Guozhen; Yu, Chao
2017-01-01
Vehicular Ad Hoc Networks (VANETs) employ multichannel to provide a variety of safety and non-safety (transport efficiency and infotainment) applications, based on the IEEE 802.11p and IEEE 1609.4 protocols. Different types of applications require different levels Quality-of-Service (QoS) support. Recently, transport efficiency and infotainment applications (e.g., electronic map download and Internet access) have received more and more attention, and this kind of applications is expected to become a big market driver in a near future. In this paper, we propose an Efficient and QoS supported Multichannel Medium Access Control (EQM-MAC) protocol for VANETs in a highway environment. The EQM-MAC protocol utilizes the service channel resources for non-safety message transmissions during the whole synchronization interval, and it dynamically adjusts minimum contention window size for different non-safety services according to the traffic conditions. Theoretical model analysis and extensive simulation results show that the EQM-MAC protocol can support QoS services, while ensuring the high saturation throughput and low transmission delay for non-safety applications. PMID:28991217
Power Aware Management Middleware for Multiple Radio Interfaces
NASA Astrophysics Data System (ADS)
Friedman, Roy; Kogan, Alex
Modern mobile phones and laptops are equipped with multiple wireless communication interfaces, such as WiFi and Bluetooth (BT), enabling the creation of ad-hoc networks. These interfaces significantly differ from one another in their power requirements, transmission range, bandwidth, etc. For example, BT is an order of magnitude more power efficient than WiFi, but its transmission range is an order of magnitude shorter. This paper introduces a management middleware that establishes a power efficient overlay for such ad-hoc networks, in which most devices can shut down their long range power hungry wireless interface (e.g., WiFi). Yet, the resulting overlay is fully connected, and for capacity and latency needs, no message ever travels more than 2k short range (e.g., BT) hops, where k is an arbitrary parameter. The paper describes the architecture of the solution and the management protocol, as well as a detailed simulations based performance study. The simulations largely validate the ability of the management infrastructure to obtain considerable power savings while keeping the network connected and maintaining reasonable latency. The performance study covers both static and mobile networks.
Assessing the State-of-the-Art in Dynamic Discovery of Ad Hoc Network Services
2001-07-18
directed -- discovery mode. It is part of the SCM_Discovery -- Module. Sends Unicast messages to SCMs on list of -- SCMS to be discovered until all... SCMS are found. -- Receives updates from SCM DB of discovered SCMs and -- removes SCMs accordingly -- NOTE: Failure and recovery behavior are not...ALLFindService10 SM4 GROUP1GroupJoin10 SCM1 SM4LinkFail5 SM4NodeFail5 ParametersCommandTime TopologyScenario Execute with Rapide For All (SM, SD, SCM
Enhanced Weight based DSR for Mobile Ad Hoc Networks
NASA Astrophysics Data System (ADS)
Verma, Samant; Jain, Sweta
2011-12-01
Routing in ad hoc network is a great problematic, since a good routing protocol must ensure fast and efficient packet forwarding, which isn't evident in ad hoc networks. In literature there exists lot of routing protocols however they don't include all the aspects of ad hoc networks as mobility, device and medium constraints which make these protocols not efficient for some configuration and categories of ad hoc networks. Thus in this paper we propose an improvement of Weight Based DSR in order to include some of the aspects of ad hoc networks as stability, remaining battery power, load and trust factor and proposing a new approach Enhanced Weight Based DSR.
A Family of ACO Routing Protocols for Mobile Ad Hoc Networks
Rupérez Cañas, Delfín; Sandoval Orozco, Ana Lucila; García Villalba, Luis Javier; Kim, Tai-hoon
2017-01-01
In this work, an ACO routing protocol for mobile ad hoc networks based on AntHocNet is specified. As its predecessor, this new protocol, called AntOR, is hybrid in the sense that it contains elements from both reactive and proactive routing. Specifically, it combines a reactive route setup process with a proactive route maintenance and improvement process. Key aspects of the AntOR protocol are the disjoint-link and disjoint-node routes, separation between the regular pheromone and the virtual pheromone in the diffusion process and the exploration of routes, taking into consideration the number of hops in the best routes. In this work, a family of ACO routing protocols based on AntOR is also specified. These protocols are based on protocol successive refinements. In this work, we also present a parallelized version of AntOR that we call PAntOR. Using programming multiprocessor architectures based on the shared memory protocol, PAntOR allows running tasks in parallel using threads. This parallelization is applicable in the route setup phase, route local repair process and link failure notification. In addition, a variant of PAntOR that consists of having more than one interface, which we call PAntOR-MI (PAntOR-Multiple Interface), is specified. This approach parallelizes the sending of broadcast messages by interface through threads. PMID:28531159
NASA Astrophysics Data System (ADS)
Mehic, M.; Fazio, P.; Voznak, M.; Partila, P.; Komosny, D.; Tovarek, J.; Chmelikova, Z.
2016-05-01
A mobile ad hoc network is a collection of mobile nodes which communicate without a fixed backbone or centralized infrastructure. Due to the frequent mobility of nodes, routes connecting two distant nodes may change. Therefore, it is not possible to establish a priori fixed paths for message delivery through the network. Because of its importance, routing is the most studied problem in mobile ad hoc networks. In addition, if the Quality of Service (QoS) is demanded, one must guarantee the QoS not only over a single hop but over an entire wireless multi-hop path which may not be a trivial task. In turns, this requires the propagation of QoS information within the network. The key to the support of QoS reporting is QoS routing, which provides path QoS information at each source. To support QoS for real-time traffic one needs to know not only minimum delay on the path to the destination but also the bandwidth available on it. Therefore, throughput, end-to-end delay, and routing overhead are traditional performance metrics used to evaluate the performance of routing protocol. To obtain additional information about the link, most of quality-link metrics are based on calculation of the lost probabilities of links by broadcasting probe packets. In this paper, we address the problem of including multiple routing metrics in existing routing packets that are broadcasted through the network. We evaluate the efficiency of such approach with modified version of DSDV routing protocols in ns-3 simulator.
Wang, Liangmin
2018-01-01
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. PMID:29538314
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.
A hierarchical detection method in external communication for self-driving vehicles based on TDMA
Al-ani, Muzhir Shaban; McDonald-Maier, Klaus
2018-01-01
Security is considered a major challenge for self-driving and semi self-driving vehicles. These vehicles depend heavily on communications to predict and sense their external environment used in their motion. They use a type of ad hoc network termed Vehicular ad hoc networks (VANETs). Unfortunately, VANETs are potentially exposed to many attacks on network and application level. This paper, proposes a new intrusion detection system to protect the communication system of self-driving cars; utilising a combination of hierarchical models based on clusters and log parameters. This security system is designed to detect Sybil and Wormhole attacks in highway usage scenarios. It is based on clusters, utilising Time Division Multiple Access (TDMA) to overcome some of the obstacles of VANETs such as high density, high mobility and bandwidth limitations in exchanging messages. This makes the security system more efficient, accurate and capable of real time detection and quick in identification of malicious behaviour in VANETs. In this scheme, each vehicle log calculates and stores different parameter values after receiving the cooperative awareness messages from nearby vehicles. The vehicles exchange their log data and determine the difference between the parameters, which is utilised to detect Sybil attacks and Wormhole attacks. In order to realize efficient and effective intrusion detection system, we use the well-known network simulator (ns-2) to verify the performance of the security system. Simulation results indicate that the security system can achieve high detection rates and effectively detect anomalies with low rate of false alarms. PMID:29315302
Gokulakrishnan, P; Ganeshkumar, P
2015-01-01
A Road Accident Prevention (RAP) scheme based on Vehicular Backbone Network (VBN) structure is proposed in this paper for Vehicular Ad-hoc Network (VANET). The RAP scheme attempts to prevent vehicles from highway road traffic accidents and thereby reduces death and injury rates. Once the possibility of an emergency situation (i.e. an accident) is predicted in advance, instantly RAP initiates a highway road traffic accident prevention scheme. The RAP scheme constitutes the following activities: (i) the Road Side Unit (RSU) constructs a Prediction Report (PR) based on the status of the vehicles and traffic in the highway roads, (ii) the RSU generates an Emergency Warning Message (EWM) based on an abnormal PR, (iii) the RSU forms a VBN structure and (iv) the RSU disseminates the EWM to the vehicles that holds the high Risk Factor (RF) and travels in High Risk Zone (HRZ). These vehicles might reside either within the RSU's coverage area or outside RSU's coverage area (reached using VBN structure). The RAP scheme improves the performance of EWM dissemination in terms of increase in notification and decrease in end-to-end delay. The RAP scheme also reduces infrastructure cost (number of RSUs) by formulating and deploying the VBN structure. The RAP scheme with VBN structure improves notification by 19 percent and end-to-end delay by 14.38 percent for a vehicle density of 160 vehicles. It is also proved from the simulation experiment that the performance of RAP scheme is promising in 4-lane highway roads.
P, Gokulakrishnan; P, Ganeshkumar
2015-01-01
A Road Accident Prevention (RAP) scheme based on Vehicular Backbone Network (VBN) structure is proposed in this paper for Vehicular Ad-hoc Network (VANET). The RAP scheme attempts to prevent vehicles from highway road traffic accidents and thereby reduces death and injury rates. Once the possibility of an emergency situation (i.e. an accident) is predicted in advance, instantly RAP initiates a highway road traffic accident prevention scheme. The RAP scheme constitutes the following activities: (i) the Road Side Unit (RSU) constructs a Prediction Report (PR) based on the status of the vehicles and traffic in the highway roads, (ii) the RSU generates an Emergency Warning Message (EWM) based on an abnormal PR, (iii) the RSU forms a VBN structure and (iv) the RSU disseminates the EWM to the vehicles that holds the high Risk Factor (RF) and travels in High Risk Zone (HRZ). These vehicles might reside either within the RSU’s coverage area or outside RSU’s coverage area (reached using VBN structure). The RAP scheme improves the performance of EWM dissemination in terms of increase in notification and decrease in end-to-end delay. The RAP scheme also reduces infrastructure cost (number of RSUs) by formulating and deploying the VBN structure. The RAP scheme with VBN structure improves notification by 19 percent and end-to-end delay by 14.38 percent for a vehicle density of 160 vehicles. It is also proved from the simulation experiment that the performance of RAP scheme is promising in 4-lane highway roads. PMID:26636576
DAWN: Dynamic Ad-hoc Wireless Network
2016-06-19
DAWN: Dynamic Ad-hoc Wireless Network The DAWN (Dynamic Ad-hoc Wireless Networks) project is developing a general theory of complex and dynamic... wireless communication networks. To accomplish this, DAWN adopts a very different approach than those followed in the past and summarized above. DAWN... wireless communication networks. The members of DAWN investigated difference aspects of wireless mobile ad hoc networks (MANET). The views, opinions and/or
Recruiting pregnant smokers from Text4baby for a randomized controlled trial of Quit4baby.
Leavitt, Leah; Abroms, Lorien; Johnson, Pamela; Schindler-Ruwisch, Jennifer; Bushar, Jessica; Singh, Indira; Cleary, Sean D; McInvale, Whitney; Turner, Monique
2017-06-01
Recruiting pregnant smokers into clinical trials is challenging since this population tends to be disadvantaged, the behavior is stigmatized, and the intervention window is limited. The purpose of this study is to test the feasibility and effectiveness of recruiting pregnant smokers into a smoking cessation trial by sending recruitment text messages to an existing subscriber list. Recruitment messages were sent to subscribers flagged as pregnant in Text4baby, a national text messaging program for pregnant women and mothers. Four recruitment messages were rotated to test the effectiveness of different emotional frames and a financial incentive. Study staff called subscribers who expressed interest to screen for eligibility and enroll eligible women. Between October 6, 2015 and February 2, 2016, 10,194 recruitment messages were sent to Text4baby subscribers flagged as pregnant, and 10.18% (1038) responded indicating interest. No significant increase in cancellation was observed compared to subscribers who received other ad hoc messages. Of respondents, 54.05% (561) were reached by phone for follow-up, and 21.97% (228) were found to be eligible. Among the eligible, 87% (199) pregnant smokers enrolled. The recruitment message with a pride emotional appeal had a significantly higher response (p = 0.02) compared to the recruitment message with no emotional appeal, but enrollment did not significantly differ between recruitment messages with different emotional appeals. The recruitment messages with a reference to financial incentive yielded higher response (p < 0.01) and enrollment (p = 0.03) compared to a recruitment message without. This study demonstrates success recruiting pregnant smokers using text message. Future studies should consider building on this approach for recruiting high-risk populations.
Trust recovery model of Ad Hoc network based on identity authentication scheme
NASA Astrophysics Data System (ADS)
Liu, Jie; Huan, Shuiyuan
2017-05-01
Mobile Ad Hoc network trust model is widely used to solve mobile Ad Hoc network security issues. Aiming at the problem of reducing the network availability caused by the processing of malicious nodes and selfish nodes in mobile Ad Hoc network routing based on trust model, an authentication mechanism based on identity authentication mobile Ad Hoc network is proposed, which uses identity authentication to identify malicious nodes, And trust the recovery of selfish nodes in order to achieve the purpose of reducing network congestion and improving network quality. The simulation results show that the implementation of the mechanism can effectively improve the network availability and security.
The Hub Population Health System: distributed ad hoc queries and alerts
Anane, Sheila; Taverna, John; Amirfar, Sam; Stubbs-Dame, Remle; Singer, Jesse
2011-01-01
The Hub Population Health System enables the creation and distribution of queries for aggregate count information, clinical decision support alerts at the point-of-care for patients who meet specified conditions, and secure messages sent directly to provider electronic health record (EHR) inboxes. Using a metronidazole medication recall, the New York City Department of Health was able to determine the number of affected patients and message providers, and distribute an alert to participating practices. As of September 2011, the system is live in 400 practices and within a year will have over 532 practices with 2500 providers, representing over 2.5 million New Yorkers. The Hub can help public health experts to evaluate population health and quality improvement activities throughout the ambulatory care network. Multiple EHR vendors are building these features in partnership with the department's regional extension center in anticipation of new meaningful use requirements. PMID:22071531
Topology Control and Routing in Ad Hoc Networks
NASA Astrophysics Data System (ADS)
Carr-Motyckova, Lenka; Navarra, Alfredo; Johansson, Tomas; Unger, Walter
Mobile nodes with the ability to communicate with radio signals may form an ad hoc network. In this chapter special problems arising for these ad hoc networks are considered. These include range control, the reduction of interferences, regulation of power consumption, and localization.
14 CFR 1203.903 - Ad hoc committees.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Ad hoc committees. 1203.903 Section 1203.903 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION INFORMATION SECURITY PROGRAM NASA Information Security Program Committee § 1203.903 Ad hoc committees. The Chairperson is authorized...
Ad Hoc Access Gateway Selection Algorithm
NASA Astrophysics Data System (ADS)
Jie, Liu
With the continuous development of mobile communication technology, Ad Hoc access network has become a hot research, Ad Hoc access network nodes can be used to expand capacity of multi-hop communication range of mobile communication system, even business adjacent to the community, improve edge data rates. For mobile nodes in Ad Hoc network to internet, internet communications in the peer nodes must be achieved through the gateway. Therefore, the key Ad Hoc Access Networks will focus on the discovery gateway, as well as gateway selection in the case of multi-gateway and handover problems between different gateways. This paper considers the mobile node and the gateway, based on the average number of hops from an average access time and the stability of routes, improved gateway selection algorithm were proposed. An improved gateway selection algorithm, which mainly considers the algorithm can improve the access time of Ad Hoc nodes and the continuity of communication between the gateways, were proposed. This can improve the quality of communication across the network.
Innovative research of AD HOC network mobility model
NASA Astrophysics Data System (ADS)
Chen, Xin
2017-08-01
It is difficult for researchers of AD HOC network to conduct actual deployment during experimental stage as the network topology is changeable and location of nodes is unfixed. Thus simulation still remains the main research method of the network. Mobility model is an important component of AD HOC network simulation. It is used to describe the movement pattern of nodes in AD HOC network (including location and velocity, etc.) and decides the movement trail of nodes, playing as the abstraction of the movement modes of nodes. Therefore, mobility model which simulates node movement is an important foundation for simulation research. In AD HOC network research, mobility model shall reflect the movement law of nodes as truly as possible. In this paper, node generally refers to the wireless equipment people carry. The main research contents include how nodes avoid obstacles during movement process and the impacts of obstacles on the mutual relation among nodes, based on which a Node Self Avoiding Obstacle, i.e. NASO model is established in AD HOC network.
Analysis on Multicast Routing Protocols for Mobile Ad Hoc Networks
NASA Astrophysics Data System (ADS)
Xiang, Ma
As the Mobile Ad Hoc Networks technologies face a series of challenges like dynamic changes of topological structure, existence of unidirectional channel, limited wireless transmission bandwidth, the capability limitations of mobile termination and etc, therefore, the research to mobile Ad Hoc network routings inevitablely undertake a more important task than those to other networks. Multicast is a mode of communication transmission oriented to group computing, which sends the data to a group of host computers by using single source address. In a typical mobile Ad Hoc Network environment, multicast has a significant meaning. On the one hand, the users of mobile Ad Hoc Network usually need to form collaborative working groups; on the other hand, this is also an important means of fully using the broadcast performances of wireless communication and effectively using the limited wireless channel resources. This paper summarizes and comparatively analyzes the routing mechanisms of various existing multicast routing protocols according to the characteristics of mobile Ad Hoc network.
14 CFR 1203.903 - Ad hoc committees.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Ad hoc committees. 1203.903 Section 1203.903 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION INFORMATION SECURITY PROGRAM NASA Information Security Program Committee § 1203.903 Ad hoc committees. The Chairperson is authorized to...
Assured Information Sharing for Ad-Hoc Collaboration
ERIC Educational Resources Information Center
Jin, Jing
2009-01-01
Collaborative information sharing tends to be highly dynamic and often ad hoc among organizations. The dynamic natures and sharing patterns in ad-hoc collaboration impose a need for a comprehensive and flexible approach to reflecting and coping with the unique access control requirements associated with the environment. This dissertation…
75 FR 43565 - NASA Advisory Council; Ad-Hoc Task Force on Planetary Defense; Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-26
... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice: (10-084)] NASA Advisory Council; Ad-Hoc Task Force on Planetary Defense; Meeting AGENCY: National Aeronautics and Space Administration. ACTION... amended, the National Aeronautics and Space Administration announces a two-part meeting of the Ad-Hoc Task...
75 FR 33838 - NASA Advisory Council; Ad-Hoc Task Force on Planetary Defense; Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-15
... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (10-065)] NASA Advisory Council; Ad-Hoc Task Force on Planetary Defense; Meeting AGENCY: National Aeronautics and Space Administration. ACTION... amended, the National Aeronautics and Space Administration announces a meeting of the Ad-Hoc Task Force on...
75 FR 15742 - NASA Advisory Council; Ad-Hoc Task Force on Planetary Defense; Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-30
... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice: (10-035)] NASA Advisory Council; Ad-Hoc Task Force on Planetary Defense; Meeting AGENCY: National Aeronautics and Space Administration. ACTION... amended, the National Aeronautics and Space Administration announces a meeting of the Ad-Hoc Task Force on...
Research of Ad Hoc Networks Access Algorithm
NASA Astrophysics Data System (ADS)
Xiang, Ma
With the continuous development of mobile communication technology, Ad Hoc access network has become a hot research, Ad Hoc access network nodes can be used to expand capacity of multi-hop communication range of mobile communication system, even business adjacent to the community, improve edge data rates. When the ad hoc network is the access network of the internet, the gateway discovery protocol is very important to choose the most appropriate gateway to guarantee the connectivity between ad hoc network and IP based fixed networks. The paper proposes a QoS gateway discovery protocol which uses the time delay and stable route to the gateway selection conditions. And according to the gateway discovery protocol, it also proposes a fast handover scheme which can decrease the handover time and improve the handover efficiency.
Energy Efficient and Stable Weight Based Clustering for Mobile Ad Hoc Networks
NASA Astrophysics Data System (ADS)
Bouk, Safdar H.; Sasase, Iwao
Recently several weighted clustering algorithms have been proposed, however, to the best of our knowledge; there is none that propagates weights to other nodes without weight message for leader election, normalizes node parameters and considers neighboring node parameters to calculate node weights. In this paper, we propose an Energy Efficient and Stable Weight Based Clustering (EE-SWBC) algorithm that elects cluster heads without sending any additional weight message. It propagates node parameters to its neighbors through neighbor discovery message (HELLO Message) and stores these parameters in neighborhood list. Each node normalizes parameters and efficiently calculates its own weight and the weights of neighboring nodes from that neighborhood table using Grey Decision Method (GDM). GDM finds the ideal solution (best node parameters in neighborhood list) and calculates node weights in comparison to the ideal solution. The node(s) with maximum weight (parameters closer to the ideal solution) are elected as cluster heads. In result, EE-SWBC fairly selects potential nodes with parameters closer to ideal solution with less overhead. Different performance metrics of EE-SWBC and Distributed Weighted Clustering Algorithm (DWCA) are compared through simulations. The simulation results show that EE-SWBC maintains fewer average numbers of stable clusters with minimum overhead, less energy consumption and fewer changes in cluster structure within network compared to DWCA.
NASA Astrophysics Data System (ADS)
Thiemann, Christian; Treiber, Martin; Kesting, Arne
2008-09-01
Intervehicle communication enables vehicles to exchange messages within a limited broadcast range and thus self-organize into dynamical and geographically embedded wireless ad hoc networks. We study the longitudinal hopping mode in which messages are transported using equipped vehicles driving in the same direction as a relay. Given a finite communication range, we investigate the conditions where messages can percolate through the network, i.e., a linked chain of relay vehicles exists between the sender and receiver. We simulate message propagation in different traffic scenarios and for different fractions of equipped vehicles. Simulations are done with both, modeled and empirical traffic data. These results are used to test the limits of applicability of an analytical model assuming a Poissonian distance distribution between the relays. We found a good agreement for homogeneous traffic scenarios and sufficiently low percentages of equipped vehicles. For higher percentages, the observed connectivity was higher than that of the model while in stop-and-go traffic situations it was lower. We explain these results in terms of correlations of the distances between the relay vehicles. Finally, we introduce variable transmission ranges and found that this additional stochastic component generally increased connectivity compared to a deterministic transmission with the same mean.
Hu, Miao; Zhong, Zhangdui; Ni, Minming; Baiocchi, Andrea
2016-11-01
Large volume content dissemination is pursued by the growing number of high quality applications for Vehicular Ad hoc NETworks(VANETs), e.g., the live road surveillance service and the video-based overtaking assistant service. For the highly dynamical vehicular network topology, beacon-less routing protocols have been proven to be efficient in achieving a balance between the system performance and the control overhead. However, to the authors' best knowledge, the routing design for large volume content has not been well considered in the previous work, which will introduce new challenges, e.g., the enhanced connectivity requirement for a radio link. In this paper, a link Lifetime-aware Beacon-less Routing Protocol (LBRP) is designed for large volume content delivery in VANETs. Each vehicle makes the forwarding decision based on the message header information and its current state, including the speed and position information. A semi-Markov process analytical model is proposed to evaluate the expected delay in constructing one routing path for LBRP. Simulations show that the proposed LBRP scheme outperforms the traditional dissemination protocols in providing a low end-to-end delay. The analytical model is shown to exhibit a good match on the delay estimation with Monte Carlo simulations, as well.
Towards an Efficient Flooding Scheme Exploiting 2-Hop Backward Information in MANETs
NASA Astrophysics Data System (ADS)
Le, Trong Duc; Choo, Hyunseung
Flooding is an indispensable operation for providing control or routing functionalities to mobile ad hoc networks (MANETs). Previously, many flooding schemes have been studied with the intention of curtailing the problems of severe redundancies, contention, and collisions in traditional implementations. A recent approach with relatively high efficiency is 1HI by Liu et al., which uses only 1-hop neighbor information. The scheme achieves local optimality in terms of the number of retransmission nodes with time complexity &Theta(n log n), where n is the number of neighbors of a node; however, this method tends to make many redundant transmissions. In this paper, we present a novel flooding algorithm, 2HBI (2-hop backward information), that efficiently reduces the number of retransmission nodes and solves the broadcast storm problem in ad hoc networks using our proposed concept, “2-hop backward information.” The most significant feature of the proposed algorithm is that it does not require any extra communication overhead other than the exchange of 1-hop HELLO messages but maintains high deliverability. Comprehensive computer simulations show that the proposed scheme significantly reduces redundant transmissions in 1HI and in pure flooding, up to 38% and 91%, respectively; accordingly it alleviates contention and collisions in networks.
Hu, Miao; Zhong, Zhangdui; Ni, Minming; Baiocchi, Andrea
2016-01-01
Large volume content dissemination is pursued by the growing number of high quality applications for Vehicular Ad hoc NETworks(VANETs), e.g., the live road surveillance service and the video-based overtaking assistant service. For the highly dynamical vehicular network topology, beacon-less routing protocols have been proven to be efficient in achieving a balance between the system performance and the control overhead. However, to the authors’ best knowledge, the routing design for large volume content has not been well considered in the previous work, which will introduce new challenges, e.g., the enhanced connectivity requirement for a radio link. In this paper, a link Lifetime-aware Beacon-less Routing Protocol (LBRP) is designed for large volume content delivery in VANETs. Each vehicle makes the forwarding decision based on the message header information and its current state, including the speed and position information. A semi-Markov process analytical model is proposed to evaluate the expected delay in constructing one routing path for LBRP. Simulations show that the proposed LBRP scheme outperforms the traditional dissemination protocols in providing a low end-to-end delay. The analytical model is shown to exhibit a good match on the delay estimation with Monte Carlo simulations, as well. PMID:27809285
ERIC Educational Resources Information Center
Sandberg, Chaleece; Sebastian, Rajani; Kiran, Swathi
2012-01-01
Background: The typicality effect is present in neurologically intact populations for natural, ad-hoc, and well-defined categories. Although sparse, there is evidence of typicality effects in persons with chronic stroke aphasia for natural and ad-hoc categories. However, it is unknown exactly what influences the typicality effect in this…
Quantum cluster variational method and message passing algorithms revisited
NASA Astrophysics Data System (ADS)
Domínguez, E.; Mulet, Roberto
2018-02-01
We present a general framework to study quantum disordered systems in the context of the Kikuchi's cluster variational method (CVM). The method relies in the solution of message passing-like equations for single instances or in the iterative solution of complex population dynamic algorithms for an average case scenario. We first show how a standard application of the Kikuchi's CVM can be easily translated to message passing equations for specific instances of the disordered system. We then present an "ad hoc" extension of these equations to a population dynamic algorithm representing an average case scenario. At the Bethe level, these equations are equivalent to the dynamic population equations that can be derived from a proper cavity ansatz. However, at the plaquette approximation, the interpretation is more subtle and we discuss it taking also into account previous results in classical disordered models. Moreover, we develop a formalism to properly deal with the average case scenario using a replica-symmetric ansatz within this CVM for quantum disordered systems. Finally, we present and discuss numerical solutions of the different approximations for the quantum transverse Ising model and the quantum random field Ising model in two-dimensional lattices.
ERIC Educational Resources Information Center
Hayajneh, Thaier Saleh
2009-01-01
Wireless ad hoc networks are suitable and sometimes the only solution for several applications. Many applications, particularly those in military and critical civilian domains (such as battlefield surveillance and emergency rescue) require that ad hoc networks be secure and stable. In fact, security is one of the main barriers to the extensive use…
ERIC Educational Resources Information Center
Clement, T.; Brown, J.; Morrison, J.; Nestel, D.
2016-01-01
General practice registrars in Australia undertake most of their vocational training in accredited general practices. They typically see patients alone from the start of their community-based training and are expected to seek timely ad hoc support from their supervisor. Such ad hoc encounters are a mechanism for ensuring patient safety, but also…
Ad Hoc Categories and False Memories: Memory Illusions for Categories Created On-The-Spot
ERIC Educational Resources Information Center
Soro, Jerônimo C.; Ferreira, Mário B.; Semin, Gün R.; Mata, André; Carneiro, Paula
2017-01-01
Three experiments were designed to test whether experimentally created ad hoc associative networks evoke false memories. We used the DRM (Deese, Roediger, McDermott) paradigm with lists of ad hoc categories composed of exemplars aggregated toward specific goals (e.g., going for a picnic) that do not share any consistent set of features. Experiment…
Ad hoc Laser networks component technology for modular spacecraft
NASA Astrophysics Data System (ADS)
Huang, Xiujun; Shi, Dele; Ma, Zongfeng; Shen, Jingshi
2016-03-01
Distributed reconfigurable satellite is a new kind of spacecraft system, which is based on a flexible platform of modularization and standardization. Based on the module data flow analysis of the spacecraft, this paper proposes a network component of ad hoc Laser networks architecture. Low speed control network with high speed load network of Microwave-Laser communication mode, no mesh network mode, to improve the flexibility of the network. Ad hoc Laser networks component technology was developed, and carried out the related performance testing and experiment. The results showed that ad hoc Laser networks components can meet the demand of future networking between the module of spacecraft.
Ad hoc laser networks component technology for modular spacecraft
NASA Astrophysics Data System (ADS)
Huang, Xiujun; Shi, Dele; Shen, Jingshi
2017-10-01
Distributed reconfigurable satellite is a new kind of spacecraft system, which is based on a flexible platform of modularization and standardization. Based on the module data flow analysis of the spacecraft, this paper proposes a network component of ad hoc Laser networks architecture. Low speed control network with high speed load network of Microwave-Laser communication mode, no mesh network mode, to improve the flexibility of the network. Ad hoc Laser networks component technology was developed, and carried out the related performance testing and experiment. The results showed that ad hoc Laser networks components can meet the demand of future networking between the module of spacecraft.
Hybrid Packet-Pheromone-Based Probabilistic Routing for Mobile Ad Hoc Networks
NASA Astrophysics Data System (ADS)
Kashkouli Nejad, Keyvan; Shawish, Ahmed; Jiang, Xiaohong; Horiguchi, Susumu
Ad-Hoc networks are collections of mobile nodes communicating using wireless media without any fixed infrastructure. Minimal configuration and quick deployment make Ad-Hoc networks suitable for emergency situations like natural disasters or military conflicts. The current Ad-Hoc networks can only support either high mobility or high transmission rate at a time because they employ static approaches in their routing schemes. However, due to the continuous expansion of the Ad-Hoc network size, node-mobility and transmission rate, the development of new adaptive and dynamic routing schemes has become crucial. In this paper we propose a new routing scheme to support high transmission rates and high node-mobility simultaneously in a big Ad-Hoc network, by combining a new proposed packet-pheromone-based approach with the Hint Based Probabilistic Protocol (HBPP) for congestion avoidance with dynamic path selection in packet forwarding process. Because of using the available feedback information, the proposed algorithm does not introduce any additional overhead. The extensive simulation-based analysis conducted in this paper indicates that the proposed algorithm offers small packet-latency and achieves a significantly higher delivery probability in comparison with the available Hint-Based Probabilistic Protocol (HBPP).
Interference Drop Scheme: Enhancing QoS Provision in Multi-Hop Ad Hoc Networks
NASA Astrophysics Data System (ADS)
Luo, Chang-Yi; Komuro, Nobuyoshi; Takahashi, Kiyoshi; Kasai, Hiroyuki; Ueda, Hiromi; Tsuboi, Toshinori
Ad hoc networking uses wireless technologies to construct networks with no physical infrastructure and so are expected to provide instant networking in areas such as disaster recovery sites and inter-vehicle communication. Unlike conventional wired networks services, services in ad hoc networks are easily disrupted by the frequent changes in traffic and topology. Therefore, solutions to assure the Quality of Services (QoS) in ad hoc networks are different from the conventional ones used in wired networks. In this paper, we propose a new queue management scheme, Interference Drop Scheme (IDS) for ad hoc networks. In the conventional queue management approaches such as FIFO (First-in First-out) and RED (Random Early Detection), a queue is usually managed by a queue length limit. FIFO discards packets according to the queue limit, and RED discards packets in an early and random fashion. IDS, on the other hand, manages the queue according to wireless interference time, which increases as the number of contentions in the MAC layer increases. When there are many MAC contentions, IDS discards TCP data packets. By observing the interference time and discarding TCP data packets, our simulation results show that IDS improves TCP performance and reduces QoS violations in UDP in ad hoc networks with chain, grid, and random topologies. Our simulation results also demonstrate that wireless interference time is a better metric than queue length limit for queue management in multi-hop ad hoc networks.
2011-09-01
LAI Location Area Identity MANET Mobile Ad - hoc Network MCC Mobile Country Code MCD Mobile Communications Device MNC Mobile Network Code ...tower or present within a geographical area. These conditions relate directly to users who often operate with mobile ad - hoc networks. These types of...infrastructures. First responders can use these mobile base stations to set up their own networks on the fly, similar to mobile ad - hoc networks
Packets Distributing Evolutionary Algorithm Based on PSO for Ad Hoc Network
NASA Astrophysics Data System (ADS)
Xu, Xiao-Feng
2018-03-01
Wireless communication network has such features as limited bandwidth, changeful channel and dynamic topology, etc. Ad hoc network has lots of difficulties in accessing control, bandwidth distribution, resource assign and congestion control. Therefore, a wireless packets distributing Evolutionary algorithm based on PSO (DPSO)for Ad Hoc Network is proposed. Firstly, parameters impact on performance of network are analyzed and researched to obtain network performance effective function. Secondly, the improved PSO Evolutionary Algorithm is used to solve the optimization problem from local to global in the process of network packets distributing. The simulation results show that the algorithm can ensure fairness and timeliness of network transmission, as well as improve ad hoc network resource integrated utilization efficiency.
Receiver-Based Ad Hoc On Demand Multipath Routing Protocol for Mobile Ad Hoc Networks
Al-Nahari, Abdulaziz; Mohamad, Mohd Murtadha
2016-01-01
Decreasing the route rediscovery time process in reactive routing protocols is challenging in mobile ad hoc networks. Links between nodes are continuously established and broken because of the characteristics of the network. Finding multiple routes to increase the reliability is also important but requires a fast update, especially in high traffic load and high mobility where paths can be broken as well. The sender node keeps re-establishing path discovery to find new paths, which makes for long time delay. In this paper we propose an improved multipath routing protocol, called Receiver-based ad hoc on demand multipath routing protocol (RB-AOMDV), which takes advantage of the reliability of the state of the art ad hoc on demand multipath distance vector (AOMDV) protocol with less re-established discovery time. The receiver node assumes the role of discovering paths when finding data packets that have not been received after a period of time. Simulation results show the delay and delivery ratio performances are improved compared with AOMDV. PMID:27258013
CSR: Constrained Selfish Routing in Ad-Hoc Networks
NASA Astrophysics Data System (ADS)
Bassem, Christine; Bestavros, Azer
Routing protocols for ad-hoc networks assume that the nodes forming the network are either under a single authority, or else that they would be altruistically forwarding data for other nodes with no expectation of a return. These assumptions are unrealistic since in ad-hoc networks, nodes are likely to be autonomous and rational (selfish), and thus unwilling to help unless they have an incentive to do so. Providing such incentives is an important aspect that should be considered when designing ad-hoc routing protocols. In this paper, we propose a dynamic, decentralized routing protocol for ad-hoc networks that provides incentives in the form of payments to intermediate nodes used to forward data for others. In our Constrained Selfish Routing (CSR) protocol, game-theoretic approaches are used to calculate payments (incentives) that ensure both the truthfulness of participating nodes and the fairness of the CSR protocol. We show through simulations that CSR is an energy efficient protocol and that it provides lower communication overhead in the best and average cases compared to existing approaches.
Receiver-Based Ad Hoc On Demand Multipath Routing Protocol for Mobile Ad Hoc Networks.
Al-Nahari, Abdulaziz; Mohamad, Mohd Murtadha
2016-01-01
Decreasing the route rediscovery time process in reactive routing protocols is challenging in mobile ad hoc networks. Links between nodes are continuously established and broken because of the characteristics of the network. Finding multiple routes to increase the reliability is also important but requires a fast update, especially in high traffic load and high mobility where paths can be broken as well. The sender node keeps re-establishing path discovery to find new paths, which makes for long time delay. In this paper we propose an improved multipath routing protocol, called Receiver-based ad hoc on demand multipath routing protocol (RB-AOMDV), which takes advantage of the reliability of the state of the art ad hoc on demand multipath distance vector (AOMDV) protocol with less re-established discovery time. The receiver node assumes the role of discovering paths when finding data packets that have not been received after a period of time. Simulation results show the delay and delivery ratio performances are improved compared with AOMDV.
Analysis of Pervasive Mobile Ad Hoc Routing Protocols
NASA Astrophysics Data System (ADS)
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.
Roberts, Nicole K; Williams, Reed G; Schwind, Cathy J; Sutyak, John A; McDowell, Christopher; Griffen, David; Wall, Jarrod; Sanfey, Hilary; Chestnut, Audra; Meier, Andreas H; Wohltmann, Christopher; Clark, Ted R; Wetter, Nathan
2014-02-01
Communication breakdowns and care coordination problems often cause preventable adverse patient care events, which can be especially acute in the trauma setting, in which ad hoc teams have little time for advanced planning. Existing teamwork curricula do not address the particular issues associated with ad hoc emergency teams providing trauma care. Ad hoc trauma teams completed a preinstruction simulated trauma encounter and were provided with instruction on appropriate team behaviors and team communication. Teams completed a postinstruction simulated trauma encounter immediately afterward and 3 weeks later, then completed a questionnaire. Blinded raters rated videotapes of the simulations. Participants expressed high levels of satisfaction and intent to change practice after the intervention. Participants changed teamwork and communication behavior on the posttest, and changes were sustained after a 3-week interval, though there was some loss of retention. Brief training exercises can change teamwork and communication behaviors on ad hoc trauma teams. Copyright © 2014 Elsevier Inc. All rights reserved.
Data Mining of Extremely Large Ad Hoc Data Sets to Produce Inverted Indices
2016-06-01
NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS Approved for public release; distribution is unlimited DATA MINING OF...COVERED Master’s Thesis 4. TITLE AND SUBTITLE DATA MINING OF EXTREMELY LARGE AD HOC DATA SETS TO PRODUCE INVERTED INDICES 5. FUNDING NUMBERS 6...INTENTIONALLY LEFT BLANK iii Approved for public release; distribution is unlimited DATA MINING OF EXTREMELY LARGE AD HOC DATA SETS TO PRODUCE
2010-09-01
secure ad-hoc networks of mobile sensors deployed in a hostile environment . These sensors are normally small 86 and resource...Communications Magazine, 51, 2008. 45. Kumar, S.A. “Classification and Review of Security Schemes in Mobile Comput- ing”. Wireless Sensor Network , 2010... Networks ”. Wireless /Mobile Network Security , 2008. 85. Xiao, Y. “Accountability for Wireless LANs, Ad Hoc Networks , and Wireless
2016-04-05
applications in wireless networks such as military battlefields, emergency response, mobile commerce , online gaming, and collaborative work are based on the...www.elsevier.com/locate/peva Performance analysis of hierarchical group key management integrated with adaptive intrusion detection in mobile ad hoc...Accepted 19 September 2010 Available online 26 September 2010 Keywords: Mobile ad hoc networks Intrusion detection Group communication systems Group
Gokulakrishnan, P.
2015-01-01
In Indian four-lane express highway, millions of vehicles are travelling every day. Accidents are unfortunate and frequently occurring in these highways causing deaths, increase in death toll, and damage to infrastructure. A mechanism is required to avoid such road accidents at the maximum to reduce the death toll. An Emergency Situation Prediction Mechanism, a novel and proactive approach, is proposed in this paper for achieving the best of Intelligent Transportation System using Vehicular Ad Hoc Network. ESPM intends to predict the possibility of occurrence of an accident in an Indian four-lane express highway. In ESPM, the emergency situation prediction is done by the Road Side Unit based on (i) the Status Report sent by the vehicles in the range of RSU and (ii) the road traffic flow analysis done by the RSU. Once the emergency situation or accident is predicted in advance, an Emergency Warning Message is constructed and disseminated to all vehicles in the area of RSU to alert and prevent the vehicles from accidents. ESPM performs well in emergency situation prediction in advance to the occurrence of an accident. ESPM predicts the emergency situation within 0.20 seconds which is comparatively less than the statistical value. The prediction accuracy of ESPM against vehicle density is found better in different traffic scenarios. PMID:26065014
Initial Report of the Deans Cyber Warfare Ad Hoc Committee
2011-12-22
in a cyber warfare environment. Among the more notable recent developments have been the establishment of a new Cyber Warfare Command (USCYBERCOM) at...information-warfare-centric organization. Clearly, future Naval Academy graduates will be expected to know more about cyber warfare than those we have...graduated in the past. The Academic Dean and Provost tasked an ad hoc committeethe Cyber Warfare ad hoc Committeeto examine how USNA can best ensure that
A Decentralized VPN Service over Generalized Mobile Ad-Hoc Networks
NASA Astrophysics Data System (ADS)
Fujita, Sho; Shima, Keiichi; Uo, Yojiro; Esaki, Hiroshi
We present a decentralized VPN service that can be built over generalized mobile ad-hoc networks (Generalized MANETs), in which topologies can be represented as a time-varying directed multigraph. We address wireless ad-hoc networks and overlay ad-hoc networks as instances of Generalized MANETs. We first propose an architecture to operate on various kinds of networks through a single set of operations. Then, we design and implement a decentralized VPN service on the proposed architecture. Through the development and operation of a prototype system we implemented, we found that the proposed architecture makes the VPN service applicable to each instance of Generalized MANETs, and that the VPN service makes it possible for unmodified applications to operate on the networks.
ERIC Educational Resources Information Center
Young, David G.
1983-01-01
Ad-hoc committees may be symbolic, informational, or action committees. A literature survey indicates such committees' structural components include a suprasystem and three subsystems involving linkages, production, and implementation. Other variables include size, personal factors, and timing. All the factors carry implications about ad-hoc…
42 CFR 422.2262 - Review and distribution of marketing materials.
Code of Federal Regulations, 2010 CFR
2010-10-01
... HUMAN SERVICES (CONTINUED) MEDICARE PROGRAM MEDICARE ADVANTAGE PROGRAM Medicare Advantage Marketing... model materials. (d) Ad hoc enrollee communication materials. Ad hoc enrollee communication materials...
2013-04-01
Capabilities Technology Demonstration Office: Ad Hoc Problem Solving as a Mechanism for Adaptive Change Kathryn Aten and John T. Dillard Naval...Defense Acquisition and the Case of the Joint Capabilities Technology Demonstration Office: Ad Hoc Problem Solving as a Mechanism for Adaptive Change...describes the preliminary analysis and findings of our study exploring what drives successful organizational adaptation in the context of technology
2013-10-01
pmlkploba=obmloq=pbofbp= Defense Acquisition and the Case of the Joint Capabilities Technology Demonstration Office: Ad Hoc Problem Solving as a...of the Joint Capabilities Technology Demonstration Office: Ad Hoc Problem Solving as a Mechanism for Adaptive Change 5a. CONTRACT NUMBER 5b. GRANT...findings of our study exploring what drives successful organizational adaptation in the context of technology transition and acquisition within the
42 CFR 423.2262 - Review and distribution of marketing materials.
Code of Federal Regulations, 2010 CFR
2010-10-01
... HUMAN SERVICES (CONTINUED) MEDICARE PROGRAM VOLUNTARY MEDICARE PRESCRIPTION DRUG BENEFIT Part D...) Ad hoc enrollee communication materials. Ad hoc enrollee communication materials may be reviewed by...
A fault-tolerant small world topology control model in ad hoc networks for search and rescue
NASA Astrophysics Data System (ADS)
Tan, Mian; Fang, Ling; Wu, Yue; Zhang, Bo; Chang, Bowen; Holme, Petter; Zhao, Jing
2018-02-01
Due to their self-organized, multi-hop and distributed characteristics, ad hoc networks are useful in search and rescue. Topology control models need to be designed for energy-efficient, robust and fast communication in ad hoc networks. This paper proposes a topology control model which specializes for search and rescue-Compensation Small World-Repeated Game (CSWRG)-which integrates mobility models, constructing small world networks and a game-theoretic approach to the allocation of resources. Simulation results show that our mobility models can enhance the communication performance of the constructed small-world networks. Our strategy, based on repeated game, can suppress selfish behavior and compensate agents that encounter selfish or faulty neighbors. This model could be useful for the design of ad hoc communication networks.
Intelligent Sensing and Classification in DSR-Based Ad Hoc Networks
NASA Astrophysics Data System (ADS)
Dempsey, Tae; Sahin, Gokhan; Morton, Yu T. (Jade
Wireless ad hoc networks have fundamentally altered today's battlefield, with applications ranging from unmanned air vehicles to randomly deployed sensor networks. Security and vulnerabilities in wireless ad hoc networks have been considered at different layers, and many attack strategies have been proposed, including denial of service (DoS) through the intelligent jamming of the most critical packet types of flows in a network. This paper investigates the effectiveness of intelligent jamming in wireless ad hoc networks using the Dynamic Source Routing (DSR) and TCP protocols and introduces an intelligent classifier to facilitate the jamming of such networks. Assuming encrypted packet headers and contents, our classifier is based solely on the observable characteristics of size, inter-arrival timing, and direction and classifies packets with up to 99.4% accuracy in our experiments.
Rapid self-organised initiation of ad hoc sensor networks close above the percolation threshold
NASA Astrophysics Data System (ADS)
Korsnes, Reinert
2010-07-01
This work shows potentials for rapid self-organisation of sensor networks where nodes collaborate to relay messages to a common data collecting unit (sink node). The study problem is, in the sense of graph theory, to find a shortest path tree spanning a weighted graph. This is a well-studied problem where for example Dijkstra’s algorithm provides a solution for non-negative edge weights. The present contribution shows by simulation examples that simple modifications of known distributed approaches here can provide significant improvements in performance. Phase transition phenomena, which are known to take place in networks close to percolation thresholds, may explain these observations. An initial method, which here serves as reference, assumes the sink node starts organisation of the network (tree) by transmitting a control message advertising its availability for its neighbours. These neighbours then advertise their current cost estimate for routing a message to the sink. A node which in this way receives a message implying an improved route to the sink, advertises its new finding and remembers which neighbouring node the message came from. This activity proceeds until there are no more improvements to advertise to neighbours. The result is a tree network for cost effective transmission of messages to the sink (root). This distributed approach has potential for simple improvements which are of interest when minimisation of storage and communication of network information are a concern. Fast organisation of the network takes place when the number k of connections for each node ( degree) is close above its critical value for global network percolation and at the same time there is a threshold for the nodes to decide to advertise network route updates.
From the Classroom to Facebook: A Fresh Approach for Youth Tobacco Prevention.
Kousoulis, Antonis A; Kympouropoulos, Stylianos P; Pouli, Dimitra K; Economopoulos, Konstantinos P; Vardavas, Constantine I
2016-05-01
The explosive rise in Internet use calls for effective ways to utilize new forms of social media to enhance school smoking prevention programs. We attempted to design and test an educational intervention for youth tobacco prevention. Intervention design and posttest pilot implementation. A single high school in Athens, Greece. Two hundred twenty-five students (aged 15-18 years). A Facebook-integrated educational intervention in six simple steps was designed and tested during an ad hoc smoking prevention lecture to high school students in Greece in order to stimulate social mobilization in online networks. Number of students with an active Facebook account, percentage posting antismoking messages within a 72-hour period, number of Facebook friends reached. Descriptive statistics. Assessed 3 days after the lecture, 15.9% of students had posted a smoking-related sentence in their Facebook account, a take-home message that was spread as a note on their wall via news feed to their 20,095 cumulative Facebook friends. One smoking-related take-home message can spread virally to a large number of adolescents through their Facebook friends. This intervention provides insight into a novel way of providing health information to youth, a hard-to-reach and vulnerable population. © The Author(s) 2016.
75 FR 20984 - Mid-Atlantic Fishery Management Council (MAFMC); Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-22
... Mid-Atlantic Fishery Management Council's (MAFMC) Ad Hoc Search Committee will hold a closed meeting... Executive Director. The Ad Hoc Search Committee will interview candidates for this position so as to...
78 FR 5190 - National Cancer Institute; Notice of Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2013-01-24
... Advisory Committee; Ad hoc Clinical Trials and Strategic Planning Subcommittee. Date: February 25, 2013... Group of the Ad hoc Clinical Trials Strategic Planning Subcommittee. Dial in number: 1-866-652-9542 and...
29 CFR 1912.11 - Terms of ad hoc committee members.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 29 Labor 7 2011-07-01 2011-07-01 false Terms of ad hoc committee members. 1912.11 Section 1912.11 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) ADVISORY COMMITTEES ON STANDARDS Organizational Matters § 1912.11 Terms of ad...
29 CFR 1912.11 - Terms of ad hoc committee members.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 29 Labor 7 2010-07-01 2010-07-01 false Terms of ad hoc committee members. 1912.11 Section 1912.11 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) ADVISORY COMMITTEES ON STANDARDS Organizational Matters § 1912.11 Terms of ad...
Mayo, Rachel; Parker, Veronica G; Sherrill, Windsor W; Coltman, Kinneil; Hudson, Matthew F; Nichols, Christina M; Yates, Adam M; Pribonic, Anne Paige
2016-06-01
This study assessed health providers' perceptions of factors related to professional interpretation services and the association between these factors and the potential use of ad hoc interpreters. Data were collected from a convenience sample of 150 health services providers at a large, regional health system in South Carolina. Providers rated "ability to communicate effectively during a clinical encounter" as paramount regarding the use of interpretation services. The most important factors related to the likely use of ad hoc interpreters (cutting corners) included locating a qualified interpreter, having to wait for a qualified interpreter, and technical difficulties regarding phone and video technology. Health care organizations may benefit from increasing staff awareness about patient safety and legal and regulatory risks involved with the use of ad hoc interpreters. © The Author(s) 2016.
Impact of network structure on the capacity of wireless multihop ad hoc communication
NASA Astrophysics Data System (ADS)
Krause, Wolfram; Glauche, Ingmar; Sollacher, Rudolf; Greiner, Martin
2004-07-01
As a representative of a complex technological system, the so-called wireless multihop ad hoc communication networks are discussed. They represent an infrastructure-less generalization of todays wireless cellular phone networks. Lacking a central control authority, the ad hoc nodes have to coordinate themselves such that the overall network performs in an optimal way. A performance indicator is the end-to-end throughput capacity. Various models, generating differing ad hoc network structure via differing transmission power assignments, are constructed and characterized. They serve as input for a generic data traffic simulation as well as some semi-analytic estimations. The latter reveal that due to the most-critical-node effect the end-to-end throughput capacity sensitively depends on the underlying network structure, resulting in differing scaling laws with respect to network size.
Kirn, Thomas J.; Westblade, Lars F.; Humphries, Romney
2017-01-01
ABSTRACT As part of the American Society for Microbiology (ASM) Evidence-Based Laboratory Medicine Practice Guidelines Committee of the Professional Practice Committee, an ad hoc committee was formed in 2014 to assess guidelines published by the committee using an assessment tool, Appraisal of Guidelines for Research Evaluation II (AGREE II). The AGREE II assessment helps reviewers determine whether published guidelines are robust, transparent, and clear in presenting practice recommendations in a standardized manner. Identifying strengths and weaknesses of practice guidelines by ad hoc assessments helps with improving future guidelines through the participation of key stakeholders. This minireview describes the development of the ad hoc committee and results from their review of several ASM best practices guidelines and a non-ASM practice guideline from the Emergency Nurses Association. PMID:28835476
Message Efficient Checkpointing and Rollback Recovery in Heterogeneous Mobile Networks
NASA Astrophysics Data System (ADS)
Jaggi, Parmeet Kaur; Singh, Awadhesh Kumar
2016-06-01
Heterogeneous networks provide an appealing way of expanding the computing capability of mobile networks by combining infrastructure-less mobile ad-hoc networks with the infrastructure-based cellular mobile networks. The nodes in such a network range from low-power nodes to macro base stations and thus, vary greatly in their capabilities such as computation power and battery power. The nodes are susceptible to different types of transient and permanent failures and therefore, the algorithms designed for such networks need to be fault-tolerant. The article presents a checkpointing algorithm for the rollback recovery of mobile hosts in a heterogeneous mobile network. Checkpointing is a well established approach to provide fault tolerance in static and cellular mobile distributed systems. However, the use of checkpointing for fault tolerance in a heterogeneous environment remains to be explored. The proposed protocol is based on the results of zigzag paths and zigzag cycles by Netzer-Xu. Considering the heterogeneity prevalent in the network, an uncoordinated checkpointing technique is employed. Yet, useless checkpoints are avoided without causing a high message overhead.
Cooper, Catherine; Fisher, Dale; Gupta, Neil; MaCauley, Rose; Pessoa-Silva, Carmem L
2016-01-05
Prior to the 2014-2015 Ebola outbreak, infection prevention and control (IPC) activities in Liberian healthcare facilities were basic. There was no national IPC guidance, nor dedicated staff at any level of government or healthcare facility (HCF) to ensure the implementation of best practices. Efforts to improve IPC early in the outbreak were ad hoc and messaging was inconsistent. In September 2014, at the height of the outbreak, the national IPC Task Force was established with a Ministry of Health (MoH) mandate to coordinate IPC response activities. A steering group of the Task Force, including representatives of the World Health Organization (WHO) and the United States Centers for Disease Control and Prevention (CDC), supported MoH leadership in implementing standardized messaging and IPC training for the health workforce. This structure, and the activities implemented under this structure, played a crucial role in the implementation of IPC practices and successful containment of the outbreak. Moving forward, a nationwide culture of IPC needs to be maintained through this governance structure in Liberia's health system to prevent and respond to future outbreaks.
Gallimberti, Luigi; Buja, Alessandra; Chindamo, Sonia; Terraneo, Alberto; Marini, Elena; Rabensteiner, Andrea; Vinelli, Angela; Gomez Perez, Luis Javier; Baldo, Vincenzo
2016-03-01
The aim of our study was to examine the association between problematic cell phone use (PCPU) for text messaging and substance abuse in young adolescents. This cross-sectional study was conducted on the basis of an ad hoc questionnaire, during the 2014-2015 school year in a province of the Veneto Region (Italy); it involved a sample of 1156 students in grades 6 to 8 (11 to 13 years old). A self-report scale based on the Short Message Service (SMS) Problem Use Diagnostic Questionnaire (SMS-PUDQ) was administered to assess the sample's PCPU. A multivariate logistic regression model was applied to seek associations between PCPU (as the dependent variable) and independent variables. The proportion of students who reported a PCPU increased with age in girls (13.5% in 6th grade, 16.4% in 7th grade, and 19.5% in 8th grade), but not in boys (14.3% in 6th grade, 18.0% in 7th grade, and 14.8% in 8th grade). Logistic regression showed that drunkenness at least once and energy drink consumption raised the odds of PCPU, whereas reading books, higher average school marks, and longer hours of sleep were associated with lower odds of PCPU in early adolescence. our findings confirm a widespread PCPU for text messaging among early adolescents. The odds of PCPU is greater in young people at risk of other substance abuse behavior.
Energy Efficient and QoS sensitive Routing Protocol for Ad Hoc Networks
NASA Astrophysics Data System (ADS)
Saeed Tanoli, Tariq; Khalid Khan, Muhammad
2013-12-01
Efficient routing is an important part of wireless ad hoc networks. Since in ad hoc networks we have limited resources, there are many limitations like bandwidth, battery consumption, and processing cycle etc. Reliability is also necessary since there is no allowance for invalid or incomplete information (and expired data is useless). There are various protocols that perform routing by considering one parameter but ignoring other parameters. In this paper we present a protocol that finds route on the basis of bandwidth, energy and mobility of the nodes participating in the communication.
Global Coverage from Ad-Hoc Constellations in Rideshare Orbits
NASA Technical Reports Server (NTRS)
Ellis, Armin; Mercury, Michael; Brown, Shannon
2012-01-01
A promising area of small satellite development is in providing higher temporal resolution than larger satellites. Traditional constellations have required specific orbits and dedicated launch vehicles. In this paper we discuss an alternative architecture in which the individual elements of the constellation are launched as rideshare opportunities. We compare the coverage of such an ad-hoc constellation with more traditional constellations. Coverage analysis is based on actual historical data from rideshare opportunities. Our analysis includes ground coverage and temporal revisits for Polar, Tropics, Temperate, and Global regions, comparing ad-hoc and Walker constellation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ahn, Gail-Joon
The project seeks an innovative framework to enable users to access and selectively share resources in distributed environments, enhancing the scalability of information sharing. We have investigated secure sharing & assurance approaches for ad-hoc collaboration, focused on Grids, Clouds, and ad-hoc network environments.
Nachamkin, Irving; Kirn, Thomas J; Westblade, Lars F; Humphries, Romney
2017-11-01
As part of the American Society for Microbiology (ASM) Evidence-Based Laboratory Medicine Practice Guidelines Committee of the Professional Practice Committee, an ad hoc committee was formed in 2014 to assess guidelines published by the committee using an assessment tool, Appraisal of Guidelines for Research Evaluation II (AGREE II). The AGREE II assessment helps reviewers determine whether published guidelines are robust, transparent, and clear in presenting practice recommendations in a standardized manner. Identifying strengths and weaknesses of practice guidelines by ad hoc assessments helps with improving future guidelines through the participation of key stakeholders. This minireview describes the development of the ad hoc committee and results from their review of several ASM best practices guidelines and a non-ASM practice guideline from the Emergency Nurses Association. Copyright © 2017 American Society for Microbiology.
Validity of using ad hoc methods to analyze secondary traits in case-control association studies.
Yung, Godwin; Lin, Xihong
2016-12-01
Case-control association studies often collect from their subjects information on secondary phenotypes. Reusing the data and studying the association between genes and secondary phenotypes provide an attractive and cost-effective approach that can lead to discovery of new genetic associations. A number of approaches have been proposed, including simple and computationally efficient ad hoc methods that ignore ascertainment or stratify on case-control status. Justification for these approaches relies on the assumption of no covariates and the correct specification of the primary disease model as a logistic model. Both might not be true in practice, for example, in the presence of population stratification or the primary disease model following a probit model. In this paper, we investigate the validity of ad hoc methods in the presence of covariates and possible disease model misspecification. We show that in taking an ad hoc approach, it may be desirable to include covariates that affect the primary disease in the secondary phenotype model, even though these covariates are not necessarily associated with the secondary phenotype. We also show that when the disease is rare, ad hoc methods can lead to severely biased estimation and inference if the true disease model follows a probit model instead of a logistic model. Our results are justified theoretically and via simulations. Applied to real data analysis of genetic associations with cigarette smoking, ad hoc methods collectively identified as highly significant (P<10-5) single nucleotide polymorphisms from over 10 genes, genes that were identified in previous studies of smoking cessation. © 2016 WILEY PERIODICALS, INC.
Game-Theoretical Design of an Adaptive Distributed Dissemination Protocol for VANETs.
Iza-Paredes, Cristhian; Mezher, Ahmad Mohamad; Aguilar Igartua, Mónica; Forné, Jordi
2018-01-19
Road safety applications envisaged for Vehicular Ad Hoc Networks (VANETs) depend largely on the dissemination of warning messages to deliver information to concerned vehicles. The intended applications, as well as some inherent VANET characteristics, make data dissemination an essential service and a challenging task in this kind of networks. This work lays out a decentralized stochastic solution for the data dissemination problem through two game-theoretical mechanisms. Given the non-stationarity induced by a highly dynamic topology, diverse network densities, and intermittent connectivity, a solution for the formulated game requires an adaptive procedure able to exploit the environment changes. Extensive simulations reveal that our proposal excels in terms of number of transmissions, lower end-to-end delay and reduced overhead while maintaining high delivery ratio, compared to other proposals.
Game-Theoretical Design of an Adaptive Distributed Dissemination Protocol for VANETs
Mezher, Ahmad Mohamad; Aguilar Igartua, Mónica
2018-01-01
Road safety applications envisaged for Vehicular Ad Hoc Networks (VANETs) depend largely on the dissemination of warning messages to deliver information to concerned vehicles. The intended applications, as well as some inherent VANET characteristics, make data dissemination an essential service and a challenging task in this kind of networks. This work lays out a decentralized stochastic solution for the data dissemination problem through two game-theoretical mechanisms. Given the non-stationarity induced by a highly dynamic topology, diverse network densities, and intermittent connectivity, a solution for the formulated game requires an adaptive procedure able to exploit the environment changes. Extensive simulations reveal that our proposal excels in terms of number of transmissions, lower end-to-end delay and reduced overhead while maintaining high delivery ratio, compared to other proposals. PMID:29351255
78 FR 47675 - Pacific Fishery Management Council; Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-06
... Pacific Fishery Management Council's (Pacific Council) Ad Hoc Groundfish Electronic Monitoring Committee and Ad Hoc Trawl Groundfish Electronic Monitoring Technical Advisory Committee (GEM Committees) will... meeting is to discuss and develop potential alternatives for electronic monitoring (EM) for vessels...
Efficient routing for safety applications in vehicular networks.
DOT National Transportation Integrated Search
2009-03-01
Vehicular ad hoc networks have received a lot of attention in recent years. This attention is due to two reasons. : First and foremost, there are a number of real-life applications that become possible in the presence of : such an ad-hoc infrastructu...
Rabin, Elaine; Patrick, Lisa
2016-04-01
Nationwide, hospitals struggle to maintain specialist on-call coverage for emergencies. We seek to further understand the issue by examining reliability of scheduled coverage and the role of ad hoc coverage when none is scheduled. An anonymous electronic survey of all emergency department (ED) directors of a large state. Overall and for 10 specialties, respondents were asked to estimate on-call coverage extent and "reliability" (frequency of emergency response in a clinically useful time frame: 2 hours), and use and effect of ad hoc emergency coverage to fill gaps. Descriptive statistics were performed using Fisher exact and Wilcoxon sign rank tests for significance. Contact information was obtained for 125 of 167 ED directors. Sixty responded (48%), representing 36% of EDs. Forty-six percent reported full on-call coverage scheduled for all specialties. Forty-six percent reported consistent reliability. Coverage and reliability were strongly related (P<.01; 33% reported both), and larger ED volume correlated with both (P<.01). Ninety percent of hospitals that had gaps in either employed ad hoc coverage, significantly improving coverage for 8 of 10 specialties. For all but 1 specialty, more than 20% of hospitals reported that specialists are "Never", "Rarely" or "Sometimes" reliable (more than 50% for cardiovascular surgery, hand surgery and ophthalmology). Significant holes in scheduled on-call specialist coverage are compounded by frequent unreliability of on-call specialists, but partially ameliorated by ad hoc specialist coverage. Regionalization may help because a 2-tiered system may exist: larger hospitals have more complete, reliable coverage. Better understanding of specialists' willingness to treat emergencies ad hoc without taking formal call will suggest additional remedies. Copyright © 2015 Elsevier Inc. All rights reserved.
Auto-Configuration Protocols in Mobile Ad Hoc Networks
Villalba, Luis Javier García; Matesanz, Julián García; Orozco, Ana Lucila Sandoval; Díaz, José Duván Márquez
2011-01-01
The TCP/IP protocol allows the different nodes in a network to communicate by associating a different IP address to each node. In wired or wireless networks with infrastructure, we have a server or node acting as such which correctly assigns IP addresses, but in mobile ad hoc networks there is no such centralized entity capable of carrying out this function. Therefore, a protocol is needed to perform the network configuration automatically and in a dynamic way, which will use all nodes in the network (or part thereof) as if they were servers that manage IP addresses. This article reviews the major proposed auto-configuration protocols for mobile ad hoc networks, with particular emphasis on one of the most recent: D2HCP. This work also includes a comparison of auto-configuration protocols for mobile ad hoc networks by specifying the most relevant metrics, such as a guarantee of uniqueness, overhead, latency, dependency on the routing protocol and uniformity. PMID:22163814
UMDR: Multi-Path Routing Protocol for Underwater Ad Hoc Networks with Directional Antenna
NASA Astrophysics Data System (ADS)
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.
MWAHCA: a multimedia wireless ad hoc cluster architecture.
Diaz, Juan R; Lloret, Jaime; Jimenez, Jose M; Sendra, Sandra
2014-01-01
Wireless Ad hoc networks provide a flexible and adaptable infrastructure to transport data over a great variety of environments. Recently, real-time audio and video data transmission has been increased due to the appearance of many multimedia applications. One of the major challenges is to ensure the quality of multimedia streams when they have passed through a wireless ad hoc network. It requires adapting the network architecture to the multimedia QoS requirements. In this paper we propose a new architecture to organize and manage cluster-based ad hoc networks in order to provide multimedia streams. Proposed architecture adapts the network wireless topology in order to improve the quality of audio and video transmissions. In order to achieve this goal, the architecture uses some information such as each node's capacity and the QoS parameters (bandwidth, delay, jitter, and packet loss). The architecture splits the network into clusters which are specialized in specific multimedia traffic. The real system performance study provided at the end of the paper will demonstrate the feasibility of the proposal.
Multicasting in Wireless Communications (Ad-Hoc Networks): Comparison against a Tree-Based Approach
NASA Astrophysics Data System (ADS)
Rizos, G. E.; Vasiliadis, D. C.
2007-12-01
We examine on-demand multicasting in ad hoc networks. The Core Assisted Mesh Protocol (CAMP) is a well-known protocol for multicast routing in ad-hoc networks, generalizing the notion of core-based trees employed for internet multicasting into multicast meshes that have much richer connectivity than trees. On the other hand, wireless tree-based multicast routing protocols use much simpler structures for determining route paths, using only parent-child relationships. In this work, we compare the performance of the CAMP protocol against the performance of wireless tree-based multicast routing protocols, in terms of two important factors, namely packet delay and ratio of dropped packets.
Gemini: Extending Information Management for Real Time Tactical Environments
2008-03-01
Mobile, Ad ‐ Hoc Networks.......................................................................................................49 8.4 Wired...networks, such as wireless ad ‐ hoc networks. This paper looked into the operating environments expected to be available to Unmanned Aircraft Systems...decentralized, ad ‐ hoc networks. The total peering capability of these networks may be very large. And, each network or access point may carry restrictions; for
ERIC Educational Resources Information Center
Heinemann, Harry N.; And Others
1988-01-01
Two articles describe the final report submitted by the Ad Hoc Committee on Cooperative Education and the Curriculum to the Cooperative Education Association and the reaction to that report by the person who established the committee. (JOW)
78 FR 10564 - Proposed Modification of Class B Airspace; Minneapolis, MN
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-14
... about the proposed design. The Ad Hoc Committee was chaired by the Minnesota Soaring Club representative... Minnesota Soaring Club and Stanton Sport Aviation operations. The Ad Hoc Committee's report provided to the... indicate the proposed modifications would impact the Minnesota Soaring Club and Stanton Sport Aviation...
What Is the Problem of Ad Hoc Hypotheses?
ERIC Educational Resources Information Center
Bamford, Greg
1999-01-01
Philosophers' attempts to convincingly explicate the received view of an ad hoc hypothesis--that it accounts for only the observations it was designed to account for--have been unsuccessful. Familiar and firmer criteria for evaluating the hypotheses or modified theories so classified are characteristically available. Contains 41 references.…
Providing Location Security in Vehicular Ad Hoc Networks
ERIC Educational Resources Information Center
Yan, Gongjun
2010-01-01
Location is fundamental information in Vehicular Ad-hoc Networks (VANETs). Almost all VANET applications rely on location information. Therefore it is of importance to ensure location information integrity, meaning that location information is original (from the generator), correct (not bogus or fabricated) and unmodified (value not changed). We…
7 CFR 3400.14 - Proposal review.
Code of Federal Regulations, 2011 CFR
2011-01-01
... RESEARCH GRANTS PROGRAM Scientific Peer Review of Research Grant Applications § 3400.14 Proposal review. (a... review will be made for responsiveness to the request for proposals (e.g., relationship of application to... peer review group, and ad hoc reviewers, as required. Written comments will be solicited from ad hoc...
Integrated Social and Quality of Service Trust Management of Mobile Groups in Ad Hoc Networks
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
The Use of English as Ad Hoc Institutional Standard in the Belgian Asylum Interview
ERIC Educational Resources Information Center
Maryns, Katrijn
2017-01-01
In institutional settings of globalization, labelled languages are generally preferred over multilingual repertoires and mobile language resources. Drawing on linguistic-ethnographic analysis of the way English is treated as an invariable "ad hoc" idiom in the Belgian asylum interview, this article demonstrates how institutional measures…
Alerts in mobile healthcare applications: requirements and pilot study.
Kafeza, Eleanna; Chiu, Dickson K W; Cheung, S C; Kafeza, Marina
2004-06-01
Recent advances in mobile technologies have greatly extended traditional communication technologies to mobile devices. At the same time, healthcare environments are by nature "mobile" where doctors and nurses do not have fixed workspaces. Irregular and exceptional events are generated in daily hospital routines, such as operations rescheduling, laboratory/examination results, and adverse drug events. These events may create requests that should be delivered to the appropriate person at the appropriate time. Those requests that are classified as urgent are referred to as alerts. Efficient routing and monitoring of alerts are keys to quality and cost-effective healthcare services. Presently, these are generally handled in an ad hoc manner. In this paper, we propose the use of a healthcare alert management system to handle these alert messages systematically. We develop a model for specifying alerts that are associated with medical tasks and a set of parameters for their routing. We design an alert monitor that matches medical staff and their mobile devices to receive alerts, based on the requirements of these alerts. We also propose a mechanism to handle and reroute, if necessary, an alert message when it has not been acknowledged within a specific deadline.
An Adaptive Jitter Mechanism for Reactive Route Discovery in Sensor Networks
Cordero, Juan Antonio; Yi, Jiazi; Clausen, Thomas
2014-01-01
This paper analyses the impact of jitter when applied to route discovery in reactive (on-demand) routing protocols. In multi-hop non-synchronized wireless networks, jitter—a small, random variation in the timing of message emission—is commonly employed, as a means to avoid collisions of simultaneous transmissions by adjacent routers over the same channel. In a reactive routing protocol for sensor and ad hoc networks, jitter is recommended during the route discovery process, specifically, during the network-wide flooding of route request messages, in order to avoid collisions. Commonly, a simple uniform jitter is recommended. Alas, this is not without drawbacks: when applying uniform jitter to the route discovery process, an effect called delay inversion is observed. This paper, first, studies and quantifies this delay inversion effect. Second, this paper proposes an adaptive jitter mechanism, designed to alleviate the delay inversion effect and thereby to reduce the route discovery overhead and (ultimately) allow the routing protocol to find more optimal paths, as compared to uniform jitter. This paper presents both analytical and simulation studies, showing that the proposed adaptive jitter can effectively decrease the cost of route discovery and increase the path quality. PMID:25111238
Galaviz-Mosqueda, Alejandro; Villarreal-Reyes, Salvador; Galeana-Zapién, Hiram; Rubio-Loyola, Javier; Covarrubias-Rosales, David H.
2014-01-01
Vehicular ad hoc networks (VANETs) have been identified as a key technology to enable intelligent transport systems (ITS), which are aimed to radically improve the safety, comfort, and greenness of the vehicles in the road. However, in order to fully exploit VANETs potential, several issues must be addressed. Because of the high dynamic of VANETs and the impairments in the wireless channel, one key issue arising when working with VANETs is the multihop dissemination of broadcast packets for safety and infotainment applications. In this paper a reliable low-overhead multihop broadcast (RLMB) protocol is proposed to address the well-known broadcast storm problem. The proposed RLMB takes advantage of the hello messages exchanged between the vehicles and it processes such information to intelligently select a relay set and reduce the redundant broadcast. Additionally, to reduce the hello messages rate dependency, RLMB uses a point-to-zone link evaluation approach. RLMB performance is compared with one of the leading multihop broadcast protocols existing to date. Performance metrics show that our RLMB solution outperforms the leading protocol in terms of important metrics such as packet dissemination ratio, overhead, and delay. PMID:25133224
EDDA: An Efficient Distributed Data Replication Algorithm in VANETs.
Zhu, Junyu; Huang, Chuanhe; Fan, Xiying; Guo, Sipei; Fu, Bin
2018-02-10
Efficient data dissemination in vehicular ad hoc networks (VANETs) is a challenging issue due to the dynamic nature of the network. To improve the performance of data dissemination, we study distributed data replication algorithms in VANETs for exchanging information and computing in an arbitrarily-connected network of vehicle nodes. To achieve low dissemination delay and improve the network performance, we control the number of message copies that can be disseminated in the network and then propose an efficient distributed data replication algorithm (EDDA). The key idea is to let the data carrier distribute the data dissemination tasks to multiple nodes to speed up the dissemination process. We calculate the number of communication stages for the network to enter into a balanced status and show that the proposed distributed algorithm can converge to a consensus in a small number of communication stages. Most of the theoretical results described in this paper are to study the complexity of network convergence. The lower bound and upper bound are also provided in the analysis of the algorithm. Simulation results show that the proposed EDDA can efficiently disseminate messages to vehicles in a specific area with low dissemination delay and system overhead.
EDDA: An Efficient Distributed Data Replication Algorithm in VANETs
Zhu, Junyu; Huang, Chuanhe; Fan, Xiying; Guo, Sipei; Fu, Bin
2018-01-01
Efficient data dissemination in vehicular ad hoc networks (VANETs) is a challenging issue due to the dynamic nature of the network. To improve the performance of data dissemination, we study distributed data replication algorithms in VANETs for exchanging information and computing in an arbitrarily-connected network of vehicle nodes. To achieve low dissemination delay and improve the network performance, we control the number of message copies that can be disseminated in the network and then propose an efficient distributed data replication algorithm (EDDA). The key idea is to let the data carrier distribute the data dissemination tasks to multiple nodes to speed up the dissemination process. We calculate the number of communication stages for the network to enter into a balanced status and show that the proposed distributed algorithm can converge to a consensus in a small number of communication stages. Most of the theoretical results described in this paper are to study the complexity of network convergence. The lower bound and upper bound are also provided in the analysis of the algorithm. Simulation results show that the proposed EDDA can efficiently disseminate messages to vehicles in a specific area with low dissemination delay and system overhead. PMID:29439443
Paving the Way Towards Reactive Planar Spanner Construction in Wireless Networks
NASA Astrophysics Data System (ADS)
Frey, Hannes; Rührup, Stefan
A spanner is a subgraph of a given graph that supports the original graph's shortest path lengths up to a constant factor. Planar spanners and their distributed construction are of particular interest for geographic routing, which is an efficient localized routing scheme for wireless ad hoc and sensor networks. Planarity of the network graph is a key criterion for guaranteed delivery, while the spanner property supports efficiency in terms of path length. We consider the problem of reactive local spanner construction, where a node's local topology is determined on demand. Known message-efficient reactive planarization algorithms do not preserve the spanner property, while reactive spanner constructions with a low message overhead have not been described so far. We introduce the concept of direct planarization which may be an enabler of efficient reactive spanner construction. Given an edge, nodes check for all incident intersecting edges a certain geometric criterion and withdraw the edge if this criterion is not satisfied. We use this concept to derive a generic reactive topology control mechanism and consider two geometric criteria. Simulation results show that direct planarization increases the performance of localized geographic routing by providing shorter paths than existing reactive approaches.
Distributed Dynamic Host Configuration Protocol (D2HCP)
Villalba, Luis Javier García; Matesanz, Julián García; Orozco, Ana Lucila Sandoval; Díaz, José Duván Márquez
2011-01-01
Mobile Ad Hoc Networks (MANETs) are multihop wireless networks of mobile nodes without any fixed or preexisting infrastructure. The topology of these networks can change randomly due to the unpredictable mobility of nodes and their propagation characteristics. In most networks, including MANETs, each node needs a unique identifier to communicate. This work presents a distributed protocol for dynamic node IP address assignment in MANETs. Nodes of a MANET synchronize from time to time to maintain a record of IP address assignments in the entire network and detect any IP address leaks. The proposed stateful autoconfiguration scheme uses the OLSR proactive routing protocol for synchronization and guarantees unique IP addresses under a variety of network conditions, including message losses and network partitioning. Simulation results show that the protocol incurs low latency and communication overhead for IP address assignment. PMID:22163856
Distributed Dynamic Host Configuration Protocol (D2HCP).
Villalba, Luis Javier García; Matesanz, Julián García; Orozco, Ana Lucila Sandoval; Díaz, José Duván Márquez
2011-01-01
Mobile Ad Hoc Networks (MANETs) are multihop wireless networks of mobile nodes without any fixed or preexisting infrastructure. The topology of these networks can change randomly due to the unpredictable mobility of nodes and their propagation characteristics. In most networks, including MANETs, each node needs a unique identifier to communicate. This work presents a distributed protocol for dynamic node IP address assignment in MANETs. Nodes of a MANET synchronize from time to time to maintain a record of IP address assignments in the entire network and detect any IP address leaks. The proposed stateful autoconfiguration scheme uses the OLSR proactive routing protocol for synchronization and guarantees unique IP addresses under a variety of network conditions, including message losses and network partitioning. Simulation results show that the protocol incurs low latency and communication overhead for IP address assignment.
Evaluation of Sexual Communication Message Strategies
2011-01-01
Parent-child communication about sex is an important proximal reproductive health outcome. But while campaigns to promote it such as the Parents Speak Up National Campaign (PSUNC) have been effective, little is known about how messages influence parental cognitions and behavior. This study examines which message features explain responses to sexual communication messages. We content analyzed 4 PSUNC ads to identify specific, measurable message and advertising execution features. We then develop quantitative measures of those features, including message strategies, marketing strategies, and voice and other stylistic features, and merged the resulting data into a dataset drawn from a national media tracking survey of the campaign. Finally, we conducted multivariable logistic regression models to identify relationships between message content and ad reactions/receptivity, and between ad reactions/receptivity and parents' cognitions related to sexual communication included in the campaign's conceptual model. We found that overall parents were highly receptive to the PSUNC ads. We did not find significant associations between message content and ad reactions/receptivity. However, we found that reactions/receptivity to specific PSUNC ads were associated with increased norms, self-efficacy, short- and long-term expectations about parent-child sexual communication, as theorized in the conceptual model. This study extends previous research and methods to analyze message content and reactions/receptivity. The results confirm and extend previous PSUNC campaign evaluation and provide further evidence for the conceptual model. Future research should examine additional message content features and the effects of reactions/receptivity. PMID:21599875
An Ad-Hoc Adaptive Pilot Model for Pitch Axis Gross Acquisition Tasks
NASA Technical Reports Server (NTRS)
Hanson, Curtis E.
2012-01-01
An ad-hoc algorithm is presented for real-time adaptation of the well-known crossover pilot model and applied to pitch axis gross acquisition tasks in a generic fighter aircraft. Off-line tuning of the crossover model to human pilot data gathered in a fixed-based high fidelity simulation is first accomplished for a series of changes in aircraft dynamics to provide expected values for model parameters. It is shown that in most cases, for this application, the traditional crossover model can be reduced to a gain and a time delay. The ad-hoc adaptive pilot gain algorithm is shown to have desirable convergence properties for most types of changes in aircraft dynamics.
Conflict Management in "Ad Hoc" Problem-Solving Groups: A Preliminary Investigation.
ERIC Educational Resources Information Center
Wallace, Les; Baxter, Leslie
Full study of small group communication must include consideration of task and socio-emotional dimensions, especially in relation to group problem solving. Thirty small groups were tested for their reactions in various "ad hoc" conflict resolution situations. Instructions to the groups were (1) no problem-solving instructions (control),…
Anomaly Detection Techniques for Ad Hoc Networks
ERIC Educational Resources Information Center
Cai, Chaoli
2009-01-01
Anomaly detection is an important and indispensable aspect of any computer security mechanism. Ad hoc and mobile networks consist of a number of peer mobile nodes that are capable of communicating with each other absent a fixed infrastructure. Arbitrary node movements and lack of centralized control make them vulnerable to a wide variety of…
MAC Protocol for Ad Hoc Networks Using a Genetic Algorithm
Elizarraras, Omar; Panduro, Marco; Méndez, Aldo L.
2014-01-01
The problem of obtaining the transmission rate in an ad hoc network consists in adjusting the power of each node to ensure the signal to interference ratio (SIR) and the energy required to transmit from one node to another is obtained at the same time. Therefore, an optimal transmission rate for each node in a medium access control (MAC) protocol based on CSMA-CDMA (carrier sense multiple access-code division multiple access) for ad hoc networks can be obtained using evolutionary optimization. This work proposes a genetic algorithm for the transmission rate election considering a perfect power control, and our proposition achieves improvement of 10% compared with the scheme that handles the handshaking phase to adjust the transmission rate. Furthermore, this paper proposes a genetic algorithm that solves the problem of power combining, interference, data rate, and energy ensuring the signal to interference ratio in an ad hoc network. The result of the proposed genetic algorithm has a better performance (15%) compared to the CSMA-CDMA protocol without optimizing. Therefore, we show by simulation the effectiveness of the proposed protocol in terms of the throughput. PMID:25140339
MWAHCA: A Multimedia Wireless Ad Hoc Cluster Architecture
Diaz, Juan R.; Jimenez, Jose M.; Sendra, Sandra
2014-01-01
Wireless Ad hoc networks provide a flexible and adaptable infrastructure to transport data over a great variety of environments. Recently, real-time audio and video data transmission has been increased due to the appearance of many multimedia applications. One of the major challenges is to ensure the quality of multimedia streams when they have passed through a wireless ad hoc network. It requires adapting the network architecture to the multimedia QoS requirements. In this paper we propose a new architecture to organize and manage cluster-based ad hoc networks in order to provide multimedia streams. Proposed architecture adapts the network wireless topology in order to improve the quality of audio and video transmissions. In order to achieve this goal, the architecture uses some information such as each node's capacity and the QoS parameters (bandwidth, delay, jitter, and packet loss). The architecture splits the network into clusters which are specialized in specific multimedia traffic. The real system performance study provided at the end of the paper will demonstrate the feasibility of the proposal. PMID:24737996
Distributed generation of shared RSA keys in mobile ad hoc networks
NASA Astrophysics Data System (ADS)
Liu, Yi-Liang; Huang, Qin; Shen, Ying
2005-12-01
Mobile Ad Hoc Networks is a totally new concept in which mobile nodes are able to communicate together over wireless links in an independent manner, independent of fixed physical infrastructure and centralized administrative infrastructure. However, the nature of Ad Hoc Networks makes them very vulnerable to security threats. Generation and distribution of shared keys for CA (Certification Authority) is challenging for security solution based on distributed PKI(Public-Key Infrastructure)/CA. The solutions that have been proposed in the literature and some related issues are discussed in this paper. The solution of a distributed generation of shared threshold RSA keys for CA is proposed in the present paper. During the process of creating an RSA private key share, every CA node only has its own private security. Distributed arithmetic is used to create the CA's private share locally, and that the requirement of centralized management institution is eliminated. Based on fully considering the Mobile Ad Hoc network's characteristic of self-organization, it avoids the security hidden trouble that comes by holding an all private security share of CA, with which the security and robustness of system is enhanced.
Post Hoc Analyses of ApoE Genotype-Defined Subgroups in Clinical Trials.
Kennedy, Richard E; Cutter, Gary R; Wang, Guoqiao; Schneider, Lon S
2016-01-01
Many post hoc analyses of clinical trials in Alzheimer's disease (AD) and mild cognitive impairment (MCI) are in small Phase 2 trials. Subject heterogeneity may lead to statistically significant post hoc results that cannot be replicated in larger follow-up studies. We investigated the extent of this problem using simulation studies mimicking current trial methods with post hoc analyses based on ApoE4 carrier status. We used a meta-database of 24 studies, including 3,574 subjects with mild AD and 1,171 subjects with MCI/prodromal AD, to simulate clinical trial scenarios. Post hoc analyses examined if rates of progression on the Alzheimer's Disease Assessment Scale-cognitive (ADAS-cog) differed between ApoE4 carriers and non-carriers. Across studies, ApoE4 carriers were younger and had lower baseline scores, greater rates of progression, and greater variability on the ADAS-cog. Up to 18% of post hoc analyses for 18-month trials in AD showed greater rates of progression for ApoE4 non-carriers that were statistically significant but unlikely to be confirmed in follow-up studies. The frequency of erroneous conclusions dropped below 3% with trials of 100 subjects per arm. In MCI, rates of statistically significant differences with greater progression in ApoE4 non-carriers remained below 3% unless sample sizes were below 25 subjects per arm. Statistically significant differences for ApoE4 in post hoc analyses often reflect heterogeneity among small samples rather than true differential effect among ApoE4 subtypes. Such analyses must be viewed cautiously. ApoE genotype should be incorporated into the design stage to minimize erroneous conclusions.
Monitoring and tracing of critical software systems: State of the work and project definition
2008-12-01
analysis, troubleshooting and debugging. Some of these subsystems already come with ad hoc tracers for events like wireless connections or SCSI disk... SQLite ). Additional synthetic events (e.g. states) are added to the database. The database thus consists in contexts (process, CPU, state), event...capability on a [operating] system-by-system basis. Additionally, the mechanics of querying the data in an ad - hoc manner outside the boundaries of the
O'Malley, Deborah A; Latimer-Cheung, Amy E
2013-11-01
This study examined how framed messages affect viewer attention to and cognitive processing of osteoporosis prevention print ads. Attention was measured with eye tracking technology. Cognitive processing was assessed through masked recall. A total of 60 college-aged women viewed 12 gain-framed, 12 loss-framed, and 12 neutral-framed ads. Number of fixations, dwell time, and recall of gain-framed osteoporosis prevention ads were higher than loss-framed or neutral-framed ads, p < .01. Message recall was positively correlated with the number of fixations and dwell time for the gain-framed and neutral-framed messages, p < .01. These findings provide preliminary insight into potential mechanisms underlying message framing effects.
Work, Family, and Community: Summary Proceedings of an Ad Hoc Committee.
ERIC Educational Resources Information Center
Hayes, Cheryl D., Ed.
These proceedings contain summaries of five working group discussions and a discussion of suggestions for future research from an ad hoc meeting on Work, Family, and Community (Fedruary 21-22, 1980) in Washington, D.C. The meeting had these objectives: (1) to identify salient policy and research issues associated with changing patterns of labor…
Modeling and optimization of Quality of Service routing in Mobile Ad hoc Networks
NASA Astrophysics Data System (ADS)
Rafsanjani, Marjan Kuchaki; Fatemidokht, Hamideh; Balas, Valentina Emilia
2016-01-01
Mobile ad hoc networks (MANETs) are a group of mobile nodes that are connected without using a fixed infrastructure. In these networks, nodes communicate with each other by forming a single-hop or multi-hop network. To design effective mobile ad hoc networks, it is important to evaluate the performance of multi-hop paths. In this paper, we present a mathematical model for a routing protocol under energy consumption and packet delivery ratio of multi-hop paths. In this model, we use geometric random graphs rather than random graphs. Our proposed model finds effective paths that minimize the energy consumption and maximizes the packet delivery ratio of the network. Validation of the mathematical model is performed through simulation.
Identification and Forecasting in Mortality Models
Nielsen, Jens P.
2014-01-01
Mortality models often have inbuilt identification issues challenging the statistician. The statistician can choose to work with well-defined freely varying parameters, derived as maximal invariants in this paper, or with ad hoc identified parameters which at first glance seem more intuitive, but which can introduce a number of unnecessary challenges. In this paper we describe the methodological advantages from using the maximal invariant parameterisation and we go through the extra methodological challenges a statistician has to deal with when insisting on working with ad hoc identifications. These challenges are broadly similar in frequentist and in Bayesian setups. We also go through a number of examples from the literature where ad hoc identifications have been preferred in the statistical analyses. PMID:24987729
Quantum load balancing in ad hoc networks
NASA Astrophysics Data System (ADS)
Hasanpour, M.; Shariat, S.; Barnaghi, P.; Hoseinitabatabaei, S. A.; Vahid, S.; Tafazolli, R.
2017-06-01
This paper presents a novel approach in targeting load balancing in ad hoc networks utilizing the properties of quantum game theory. This approach benefits from the instantaneous and information-less capability of entangled particles to synchronize the load balancing strategies in ad hoc networks. The quantum load balancing (QLB) algorithm proposed by this work is implemented on top of OLSR as the baseline routing protocol; its performance is analyzed against the baseline OLSR, and considerable gain is reported regarding some of the main QoS metrics such as delay and jitter. Furthermore, it is shown that QLB algorithm supports a solid stability gain in terms of throughput which stands a proof of concept for the load balancing properties of the proposed theory.
Information Fusion in Ad hoc Wireless Sensor Networks for Aircraft Health Monitoring
NASA Astrophysics Data System (ADS)
Fragoulis, Nikos; Tsagaris, Vassilis; Anastassopoulos, Vassilis
In this paper the use of an ad hoc wireless sensor network for implementing a structural health monitoring system is discussed. The network is consisted of sensors deployed throughout the aircraft. These sensors being in the form of a microelectronic chip and consisted of sensing, data processing and communicating components could be easily embedded in any mechanical aircraft component. The established sensor network, due to its ad hoc nature is easily scalable, allowing adding or removing any number of sensors. The position of the sensor nodes need not necessarily to be engineered or predetermined, giving this way the ability to be deployed in inaccessible points. Information collected from various sensors of different modalities throughout the aircraft is then fused in order to provide a more comprehensive image of the aircraft structural health. Sensor level fusion along with decision quality information is used, in order to enhance detection performance.
NASA Astrophysics Data System (ADS)
Park, Joon-Sang; Lee, Uichin; Oh, Soon Young; Gerla, Mario; Lun, Desmond Siumen; Ro, Won Woo; Park, Joonseok
Vehicular ad hoc networks (VANET) aims to enhance vehicle navigation safety by providing an early warning system: any chance of accidents is informed through the wireless communication between vehicles. For the warning system to work, it is crucial that safety messages be reliably delivered to the target vehicles in a timely manner and thus reliable and timely data dissemination service is the key building block of VANET. Data mulling technique combined with three strategies, network codeing, erasure coding and repetition coding, is proposed for the reliable and timely data dissemination service. Particularly, vehicles in the opposite direction on a highway are exploited as data mules, mobile nodes physically delivering data to destinations, to overcome intermittent network connectivity cause by sparse vehicle traffic. Using analytic models, we show that in such a highway data mulling scenario the network coding based strategy outperforms erasure coding and repetition based strategies.
Genomics-Based Security Protocols: From Plaintext to Cipherprotein
NASA Technical Reports Server (NTRS)
Shaw, Harry; Hussein, Sayed; Helgert, Hermann
2011-01-01
The evolving nature of the internet will require continual advances in authentication and confidentiality protocols. Nature provides some clues as to how this can be accomplished in a distributed manner through molecular biology. Cryptography and molecular biology share certain aspects and operations that allow for a set of unified principles to be applied to problems in either venue. A concept for developing security protocols that can be instantiated at the genomics level is presented. A DNA (Deoxyribonucleic acid) inspired hash code system is presented that utilizes concepts from molecular biology. It is a keyed-Hash Message Authentication Code (HMAC) capable of being used in secure mobile Ad hoc networks. It is targeted for applications without an available public key infrastructure. Mechanics of creating the HMAC are presented as well as a prototype HMAC protocol architecture. Security concepts related to the implementation differences between electronic domain security and genomics domain security are discussed.
Self-Configuration and Self-Optimization Process in Heterogeneous Wireless Networks
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
Self-configuration and self-optimization process in heterogeneous wireless networks.
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.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Longcope, D. W.; Klimchuk, J. A.
Aspects of solar flare dynamics, such as chromospheric evaporation and flare light curves, have long been studied using one-dimensional models of plasma dynamics inside a static flare loop, subjected to some energy input. While extremely successful at explaining the observed characteristics of flares, all such models so far have specified energy input ad hoc, rather than deriving it self-consistently. There is broad consensus that flares are powered by magnetic energy released through reconnection. Recent work has generalized Petschek’s basic reconnection scenario, topological change followed by field line retraction and shock heating, to permit its inclusion in a one-dimensional flare loop model. Heremore » we compare the gas dynamics driven by retraction and shocking to those from more conventional static loop models energized by ad hoc source terms. We find significant differences during the first minute, when retraction leads to larger kinetic energies and produces higher densities at the loop top, while ad hoc heating tends to rarify the loop top. The loop-top density concentration is related to the slow magnetosonic shock, characteristic of Petschek’s model, but persists beyond the retraction phase occurring in the outflow jet. This offers an explanation for observed loop-top sources of X-ray and EUV emission, with advantages over that provided by ad hoc heating scenarios. The cooling phases of the two models are, however, notably similar to one another, suggesting that observations at that stage will yield little information on the nature of energy input.« less
Efficient Byzantine Fault Tolerance for Scalable Storage and Services
2009-07-01
most critical applications must survive in ever harsher environments. Less synchronous networking delivers packets unreliably and unpredictably, and... synchronous environments to allowing asynchrony, and from tolerating crashes to tolerating some corruptions through ad-hoc consistency checks. Ad-hoc...servers are responsive. To support this thesis statement, this disseration takes the following steps. First, it develops a new cryptographic primitive
ERIC Educational Resources Information Center
Nevada State Dept. of Conservation and Natural Resources, Carson City.
The Environmental Quality Ad Hoc Committee has prepared this report for the Governor's Natural Resources Council (Nevada). It is a compilation of available factual data focusing attention on needed statutory and administrative changes to preserve Nevada's environmental heritage and from which recommendations for future budgetary and legislative…
Report of the Ad Hoc Committee on Religious and Cultural Celebrations in the Library.
ERIC Educational Resources Information Center
Rathemacher, Andree; Grubman, Sheila Black; Lahiri, Amar; Gilton, Donna; Sharif, Mohammed
The charge of the University of Rhode Island's Ad Hoc Committee on Religious and Cultural Celebrations in the Library was to: investigate all opportunities for the library to educate the campus community about religious and cultural holidays; consider all the major religions of the world and the possibility of having displays for the symbols of…
ERIC Educational Resources Information Center
Joint Committee on Printing, Washington, DC.
Designed to present a better understanding of the government's system of printing and distributing information and to highlight problems, alternatives, and important policy questions, this report synthesizes 13 weeks of the Ad Hoc Advisory Committee hearings on six topics: (1) Administration of policy--who should establish and administer policy in…
The 5th Meeting of the Ad Hoc Panel on Terminal Configured Vehicles
NASA Technical Reports Server (NTRS)
1977-01-01
A report of the fifth meeting of the NASA Research and Technology Advisory Council, Ad Hoc panel on Terminal Configured Vehicles is presented. Some of the following topics were discussed; (1) microwave landing systems; (2) whole word computer system status; (3) flight path angle control: (4) VTOL approaches and landing technology; and (5) simulation study in wind shear.
Nápoles, Anna M.; Santoyo-Olsson, Jasmine; Karliner, Leah S.; O’Brien, Helen; Gregorich, Steven E.; Pérez-Stable, Eliseo J.
2013-01-01
Language interpretation ameliorates health disparities among underserved limited English-proficient patients, yet few studies have compared clinician satisfaction with these services. Self-administered clinician post-visit surveys compared the quality of interpretation and communication, visit satisfaction, degree of patient engagement, and cultural competence of visits using untrained people acting as interpreters (ad hoc), in-person professional, or video conferencing professional interpretation for 283 visits. Adjusting for clinician and patient characteristics, the quality of interpretation of in-person and video conferencing modes were rated similarly (OR=1.79; 95% CI 0.74, 4.33). The quality of in-person (OR=5.55; 95% CI 1.50, 20.51) and video conferencing (OR=3.10; 95% CI 1.16, 8.31) were rated higher than ad hoc interpretation. Self-assessed cultural competence was better for in-person versus video conferencing interpretation (OR=2.32; 95% CI 1.11, 4.86). Video conferencing interpretation increases access without compromising quality, but cultural nuances may be better addressed by in-person interpreters. Professional interpretation is superior to ad hoc (OR=4.15; 95% CI 1.43, 12.09). PMID:20173271
Two Phase Admission Control for QoS Mobile Ad Hoc Networks
NASA Astrophysics Data System (ADS)
Chen, Chien-Sheng; Su, Yi-Wen; Liu, Wen-Hsiung; Chi, Ching-Lung
In this paper a novel and effective two phase admission control (TPAC) for QoS mobile ad hoc networks is proposed that satisfies the real-time traffic requirements in mobile ad hoc networks. With a limited amount of extra overhead, TPAC can avoid network congestions by a simple and precise admission control which blocks most of the overloading flow-requests in the route discovery process. When compared with previous QoS routing schemes such as QoS-aware routing protocol and CACP protocols, it is shown from system simulations that the proposed scheme can increase the system throughput and reduce both the dropping rate and the end-to-end delay. Therefore, TPAC is surely an effective QoS-guarantee protocol to provide for real-time traffic.
Passive and Active Analysis in DSR-Based Ad Hoc Networks
NASA Astrophysics Data System (ADS)
Dempsey, Tae; Sahin, Gokhan; Morton, Y. T. (Jade)
Security and vulnerabilities in wireless ad hoc networks have been considered at different layers, and many attack strategies have been proposed, including denial of service (DoS) through the intelligent jamming of the most critical packet types of flows in a network. This paper investigates the effectiveness of intelligent jamming in wireless ad hoc networks using the Dynamic Source Routing (DSR) and TCP protocols and introduces an intelligent classifier to facilitate the jamming of such networks. Assuming encrypted packet headers and contents, our classifier is based solely on the observable characteristics of size, inter-arrival timing, and direction and classifies packets with up to 99.4% accuracy in our experiments. Furthermore, we investigate active analysis, which is the combination of a classifier and intelligent jammer to invoke specific responses from a victim network.
Information Sharing Modalities for Mobile Ad-Hoc Networks
NASA Astrophysics Data System (ADS)
de Spindler, Alexandre; Grossniklaus, Michael; Lins, Christoph; Norrie, Moira C.
Current mobile phone technologies have fostered the emergence of a new generation of mobile applications. Such applications allow users to interact and share information opportunistically when their mobile devices are in physical proximity or close to fixed installations. It has been shown how mobile applications such as collaborative filtering and location-based services can take advantage of ad-hoc connectivity to use physical proximity as a filter mechanism inherent to the application logic. We discuss the different modes of information sharing that arise in such settings based on the models of persistence and synchronisation. We present a platform that supports the development of applications that can exploit these modes of ad-hoc information sharing and, by means of an example, show how such an application can be realised based on the supported event model.
Wagener, Johannes; Spjuth, Ola; Willighagen, Egon L; Wikberg, Jarl ES
2009-01-01
Background Life sciences make heavily use of the web for both data provision and analysis. However, the increasing amount of available data and the diversity of analysis tools call for machine accessible interfaces in order to be effective. HTTP-based Web service technologies, like the Simple Object Access Protocol (SOAP) and REpresentational State Transfer (REST) services, are today the most common technologies for this in bioinformatics. However, these methods have severe drawbacks, including lack of discoverability, and the inability for services to send status notifications. Several complementary workarounds have been proposed, but the results are ad-hoc solutions of varying quality that can be difficult to use. Results We present a novel approach based on the open standard Extensible Messaging and Presence Protocol (XMPP), consisting of an extension (IO Data) to comprise discovery, asynchronous invocation, and definition of data types in the service. That XMPP cloud services are capable of asynchronous communication implies that clients do not have to poll repetitively for status, but the service sends the results back to the client upon completion. Implementations for Bioclipse and Taverna are presented, as are various XMPP cloud services in bio- and cheminformatics. Conclusion XMPP with its extensions is a powerful protocol for cloud services that demonstrate several advantages over traditional HTTP-based Web services: 1) services are discoverable without the need of an external registry, 2) asynchronous invocation eliminates the need for ad-hoc solutions like polling, and 3) input and output types defined in the service allows for generation of clients on the fly without the need of an external semantics description. The many advantages over existing technologies make XMPP a highly interesting candidate for next generation online services in bioinformatics. PMID:19732427
Wagener, Johannes; Spjuth, Ola; Willighagen, Egon L; Wikberg, Jarl E S
2009-09-04
Life sciences make heavily use of the web for both data provision and analysis. However, the increasing amount of available data and the diversity of analysis tools call for machine accessible interfaces in order to be effective. HTTP-based Web service technologies, like the Simple Object Access Protocol (SOAP) and REpresentational State Transfer (REST) services, are today the most common technologies for this in bioinformatics. However, these methods have severe drawbacks, including lack of discoverability, and the inability for services to send status notifications. Several complementary workarounds have been proposed, but the results are ad-hoc solutions of varying quality that can be difficult to use. We present a novel approach based on the open standard Extensible Messaging and Presence Protocol (XMPP), consisting of an extension (IO Data) to comprise discovery, asynchronous invocation, and definition of data types in the service. That XMPP cloud services are capable of asynchronous communication implies that clients do not have to poll repetitively for status, but the service sends the results back to the client upon completion. Implementations for Bioclipse and Taverna are presented, as are various XMPP cloud services in bio- and cheminformatics. XMPP with its extensions is a powerful protocol for cloud services that demonstrate several advantages over traditional HTTP-based Web services: 1) services are discoverable without the need of an external registry, 2) asynchronous invocation eliminates the need for ad-hoc solutions like polling, and 3) input and output types defined in the service allows for generation of clients on the fly without the need of an external semantics description. The many advantages over existing technologies make XMPP a highly interesting candidate for next generation online services in bioinformatics.
Effects of message framing and visual-fear appeals on smoker responses to antismoking ads.
Kang, Jungsuk; Lin, Carolyn A
2015-01-01
This study examined the effects of antismoking ads on Korean adult male smokers. An experiment was conducted to explore how message framing and visual-fear appeals embedded in antismoking ads may influence ad-evoked fear, threat appraisals, and intention to quit smoking. Results showed that (a) antismoking ad exposure increased ad-evoked fear and cessation intention; (b) optimistic bias was stronger when the visual-fear appeal was absent in antismoking ads; and (c) preexposure cessation intension as well as postexposure perceived severity and optimistic bias were positively predictive of smokers' postexposure cessation intention The study provided the first preliminary empirical evidence for validating the combined effects of message frames and visual-fear appeals in antismoking ads on facilitating cessation intention.
Ad-Hoc Networks and the Mobile Application Security System (MASS)
2006-01-01
solution to this problem that addresses critical aspects of security in ad-hoc mobile application networks. This approach involves preventing unauthorized...modification of a mobile application , both by other applications and by hosts, and ensuring that mobile code is authentic and authorized. These...capabilities constitute the Mobile Application Security System (MASS). The MASS applies effective, robust security to mobile application -based systems
ARO PECASE: Information Assurance for Energy-Constrained Wireless Sensor Networks
2011-12-21
Distribution, 18th Annual IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC), September 2007. 2. 2010 IEEE...received the following awards: Student Best Paper Award at the IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC...Localization in Wireless Ad Hoc Networks – Many current and future appli- cations of mobile ad hoc networks, including disaster response and event
AD HOC Networks for the Autonomous Car
NASA Astrophysics Data System (ADS)
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 protocols show lower performance with ARIANDE being superior to SAODV and SRP. Nevertheless all protocol simulation proved it to match required real time performance.
Examining the link between framed physical activity ads and behavior among women.
Berenbaum, Erin; Latimer-Cheung, Amy E
2014-06-01
Gain-framed messages are more effective at promoting physical activity than loss-framed messages. However, the mechanism through which this effect occurs is unclear. The current experiment examined the effects of message framing on variables described in the communication behavior change model (McGuire, 1989), as well as the mediating effects of these variables on the message-frame-behavior relationship. Sixty low-to-moderately active women viewed 20 gain- or loss-framed ads and five control ads while their eye movements were recorded via eye tracking. The gain-framed ads attracted greater attention, ps < .05; produced more positive attitudes, p = .06; were better recalled, p < .001; influenced decisions to be active, p = .07; and had an immediate and delayed impact on behavior, ps < .05, compared with the loss-framed messages. Mediation analyses failed to reveal any significant effects. This study demonstrates the effects of framed messages on several outcomes; however, the mechanisms underlying these effects remain unclear.
LoDolce, Megan E; Harris, Jennifer L; Schwartz, Marlene B
2013-01-01
Marketing that targets children with energy-dense, nutrient-poor foods is a likely contributor to the childhood obesity crisis. High-sugar ready-to-eat cereals are the packaged food most frequently promoted in child-targeted food advertising on television. The authors combined content analysis of product nutritional quality and messages presented in cereal television advertisements with syndicated data on exposure to those ads. The analysis quantifies children's exposure to specific products and messages that appear in advertisements and compares it with adult exposure. Children viewed 1.7 ads per day for ready-to-eat cereals, and 87% of those ads promoted high-sugar products; adults viewed half as many ads, and ads viewed were equally likely to promote high- and low-sugar cereals. In addition, the messages presented in high-sugar ads viewed by children were significantly more likely to convey unrealistic and contradictory messages about cereal attributes and healthy eating. For example, 91% of high-sugar cereal ads viewed by children ascribed extraordinary powers to these products, and 67% portrayed healthy and unhealthy eating behaviors. Given children's vulnerability to the influence of advertising, the emotional and mixed messages used to promote high-sugar cereals are confusing and potentially misleading.
Lee, Seungae; Mackert, Michael
2017-01-01
Self-referencing effects explain why many advertisements try to relate people with the ads; when an individual relates an ad to the self, the person will be more likely to recall the ad. However, this study revealed that the regulatory focus of messages is a boundary condition for self-referencing strategy. Self-referencing did not yield a positive persuasion effect in prevention-focused messages. The underlying message process analyses further revealed people avoid elaborating prevention-focused messages when used with self-referencing, rather than viewing them in a biased manner. The findings provide guidance for health communication practitioners' use of self-referencing statements.
Diamond, Lisa C; Tuot, Delphine S; Karliner, Leah S
2012-01-01
Language barriers present a substantial communication challenge in the hospital setting. To describe how clinicians with various levels of Spanish language proficiency work with interpreters or their own Spanish skills in common clinical scenarios. Survey of physicians and nurses who report ever speaking Spanish with patients on a general medicine hospital floor. Spanish proficiency rated on a 5-point scale, self-reported use of specific strategies (own Spanish skills, professional or ad-hoc interpreters) to overcome the language barrier. Sixty-eight physicians and 65 nurses participated. Physicians with low-level Spanish proficiency reported frequent use of ad-hoc interpreters for all information-based scenarios, except pre-rounding in the morning when most reported using their own Spanish skills. For difficult conversations and procedural consent, most used professional interpreters. Comparatively, physicians with medium proficiency reported higher rates of using their own Spanish skills for information-based scenarios, lower rates of professional interpreter use, and little use of ad-hoc interpreters. They rarely used their own Spanish skills or ad-hoc interpreters for difficult conversations. Physicians with high-level Spanish proficiency almost uniformly reported using their own Spanish skills. The majority (82%) of nurses had low-level Spanish proficiency, and frequently worked with professional interpreters for educating patients, but more often used ad hoc interpreters and their own Spanish skills for information-based scenarios, including medication administration. Physicians and nurses with limited Spanish proficiency use these skills, even in important clinical circumstances in the hospital. Health-care organizations should evaluate clinicians' non-English language proficiency and set policies about use of language skills in clinical care.
Cross-layer model design in wireless ad hoc networks for the Internet of Things.
Yang, Xin; Wang, Ling; Xie, Jian; Zhang, Zhaolin
2018-01-01
Wireless ad hoc networks can experience extreme fluctuations in transmission traffic in the Internet of Things, which is widely used today. Currently, the most crucial issues requiring attention for wireless ad hoc networks are making the best use of low traffic periods, reducing congestion during high traffic periods, and improving transmission performance. To solve these problems, the present paper proposes a novel cross-layer transmission model based on decentralized coded caching in the physical layer and a content division multiplexing scheme in the media access control layer. Simulation results demonstrate that the proposed model effectively addresses these issues by substantially increasing the throughput and successful transmission rate compared to existing protocols without a negative influence on delay, particularly for large scale networks under conditions of highly contrasting high and low traffic periods.
Cross-layer model design in wireless ad hoc networks for the Internet of Things
Wang, Ling; Xie, Jian; Zhang, Zhaolin
2018-01-01
Wireless ad hoc networks can experience extreme fluctuations in transmission traffic in the Internet of Things, which is widely used today. Currently, the most crucial issues requiring attention for wireless ad hoc networks are making the best use of low traffic periods, reducing congestion during high traffic periods, and improving transmission performance. To solve these problems, the present paper proposes a novel cross-layer transmission model based on decentralized coded caching in the physical layer and a content division multiplexing scheme in the media access control layer. Simulation results demonstrate that the proposed model effectively addresses these issues by substantially increasing the throughput and successful transmission rate compared to existing protocols without a negative influence on delay, particularly for large scale networks under conditions of highly contrasting high and low traffic periods. PMID:29734355
A novel Smart Routing Protocol for remote health monitoring in Medical Wireless Networks.
Sundararajan, T V P; Sumithra, M G; Maheswar, R
2014-01-01
In a Medical Wireless Network (MWN), sensors constantly monitor patient's physiological condition and movement. Inter-MWN communications are set up between the Patient Server and one or more Centralized Coordinators. However, MWNs require protocols with little energy consumption and the self-organizing attribute perceived in ad-hoc networks. The proposed Smart Routing Protocol (SRP) selects only the nodes with a higher residual energy and lower traffic density for routing. This approach enhances cooperation among the nodes of a Mobile Ad Hoc Network. Consequently, SRP produces better results than the existing protocols, namely Conditional Min-Max Battery Cost Routing, Min-Max Battery Cost Routing and AdHoc On-demand Distance Vector in terms of network parameters. The performance of the erstwhile schemes for routing protocols is evaluated using the network simulator Qualnet v 4.5.
The Traffic Adaptive Data Dissemination (TrAD) Protocol for both Urban and Highway Scenarios.
Tian, Bin; Hou, Kun Mean; Zhou, Haiying
2016-06-21
The worldwide economic cost of road crashes and injuries is estimated to be US$518 billion per year and the annual congestion cost in France is estimated to be €5.9 billion. Vehicular Ad hoc Networks (VANETs) are one solution to improve transport features such as traffic safety, traffic jam and infotainment on wheels, where a great number of event-driven messages need to be disseminated in a timely way in a region of interest. In comparison with traditional wireless networks, VANETs have to consider the highly dynamic network topology and lossy links due to node mobility. Inter-Vehicle Communication (IVC) protocols are the keystone of VANETs. According to our survey, most of the proposed IVC protocols focus on either highway or urban scenarios, but not on both. Furthermore, too few protocols, considering both scenarios, can achieve high performance. In this paper, an infrastructure-less Traffic Adaptive data Dissemination (TrAD) protocol which takes into account road traffic and network traffic status for both highway and urban scenarios will be presented. TrAD has double broadcast suppression techniques and is designed to adapt efficiently to the irregular road topology. The performance of the TrAD protocol was evaluated quantitatively by means of realistic simulations taking into account different real road maps, traffic routes and vehicular densities. The obtained simulation results show that TrAD is more efficient in terms of packet delivery ratio, number of transmissions and delay in comparison with the performance of three well-known reference protocols. Moreover, TrAD can also tolerate a reasonable degree of GPS drift and still achieve efficient data dissemination.
The Traffic Adaptive Data Dissemination (TrAD) Protocol for both Urban and Highway Scenarios
Tian, Bin; Hou, Kun Mean; Zhou, Haiying
2016-01-01
The worldwide economic cost of road crashes and injuries is estimated to be US$518 billion per year and the annual congestion cost in France is estimated to be €5.9 billion. Vehicular Ad hoc Networks (VANETs) are one solution to improve transport features such as traffic safety, traffic jam and infotainment on wheels, where a great number of event-driven messages need to be disseminated in a timely way in a region of interest. In comparison with traditional wireless networks, VANETs have to consider the highly dynamic network topology and lossy links due to node mobility. Inter-Vehicle Communication (IVC) protocols are the keystone of VANETs. According to our survey, most of the proposed IVC protocols focus on either highway or urban scenarios, but not on both. Furthermore, too few protocols, considering both scenarios, can achieve high performance. In this paper, an infrastructure-less Traffic Adaptive data Dissemination (TrAD) protocol which takes into account road traffic and network traffic status for both highway and urban scenarios will be presented. TrAD has double broadcast suppression techniques and is designed to adapt efficiently to the irregular road topology. The performance of the TrAD protocol was evaluated quantitatively by means of realistic simulations taking into account different real road maps, traffic routes and vehicular densities. The obtained simulation results show that TrAD is more efficient in terms of packet delivery ratio, number of transmissions and delay in comparison with the performance of three well-known reference protocols. Moreover, TrAD can also tolerate a reasonable degree of GPS drift and still achieve efficient data dissemination. PMID:27338393
A Survey on Trust Management for Mobile Ad Hoc Networks
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
2014-03-01
38 2. Mobile Ad Hoc Networks ..................................................................39 3. Wireless Ad Hoc Sensor Networks...59 Figure 32. RENEWS with WiMAX and Wave Relay AP at C-IED Site.............................59 Figure 33. RENEWS Wind Turbine and Solar Panels at Hat...worldwide interoperability for microwave access WSN wireless sensor network xv ACKNOWLEDGMENTS We would like to express our sincerest gratitude
Space-Time Processing for Tactical Mobile Ad Hoc Networks
2007-08-01
rates in mobile ad hoc networks. In addition, he has considered the design of a cross-layer multi-user resource allocation framework using a... framework for many-to-one communication. In this context, multiple nodes cooperate to transmit their packets simultaneously to a single node using multi...spatially multiplexed signals transmitted from multiple nodes. Our goal is to form a framework that activates different sets of communication links
Space-Time Processing for Tactical Mobile Ad Hoc Networks
2008-08-01
vision for multiple concurrent communication settings, i.e., a many-to-many framework where multi-packet transmissions (MPTs) and multi-packet...modelling framework of capacity-delay tradeoffs We have introduced the first unified modeling framework for the computation of fundamental limits o We...dalities in wireless n twor i-packet modelling framework to account for the use of m lti-packet reception (MPR) f ad hoc networks with MPT under
1979-12-01
team progranming in reducing software dleveloup- ment costs relative to ad hoc approaches and improving software product quality relative to...are interpreted as demonstrating the advantages of disciplined team programming in reducing software development costs relative to ad hoc approaches...is due oartialty to the cost and imoracticality of a valiI experimental setup within a oroauct ion environment. Thus the question remains, are
An Energy Efficient Power Control Protocol for Ad Hoc Networks Using Directional Antennas
NASA Astrophysics Data System (ADS)
Quiroz-Perez, Carlos; Gulliver, T. Aaron
A wireless ad hoc network is a collection of mobile nodes that can communicate with each other. Typically, nodes employ omnidirectional antennas. The use of directional antennas can increase spatial reuse, reduce the number of hops to a destination, reduce interference, and increase the transmission range in a specific direction. This is because omnidirectional antennas radiate equally in all directions, limiting the transmission range.
ERIC Educational Resources Information Center
Leroy, Norah
2017-01-01
This paper addresses the theme of social inclusion through language learning. The focus is on an ad-hoc tutoring scheme set up between newly arrived British migrant pupils and French monolingual pupils in a small secondary school in the south-west of France. Though the original objective of this tutoring scheme was to improve the English skills of…
Overview of the TREC-2014 Microblog Track
2014-11-01
tweets as part of writing a retrospective piece about the impact of social media on the Egyptian revolution. The topic is temporally-anchored in the...imagined that participants would tackle the TTG task in a pipelined architecture that begins with ad hoc retrieval followed by summary generation...random selection of 100 tweets per topic from each TTG run. Although we envisioned a sys- tem architecture consisting of ad hoc retrieval followed by
Sarafijanović, Slavisa; Le Boudec, Jean-Yves
2005-09-01
In mobile ad hoc networks, nodes act both as terminals and information relays, and they participate in a common routing protocol, such as dynamic source routing (DSR). The network is vulnerable to routing misbehavior, due to faulty or malicious nodes. Misbehavior detection systems aim at removing this vulnerability. In this paper, we investigate the use of an artificial immune system (AIS) to detect node misbehavior in a mobile ad hoc network using DSR. The system is inspired by the natural immune system (IS) of vertebrates. Our goal is to build a system that, like its natural counterpart, automatically learns, and detects new misbehavior. We describe our solution for the classification task of the AIS; it employs negative selection and clonal selection, the algorithms for learning and adaptation used by the natural IS. We define how we map the natural IS concepts such as self, antigen, and antibody to a mobile ad hoc network and give the resulting algorithm for classifying nodes as misbehaving. We implemented the system in the network simulator Glomosim; we present detection results and discuss how the system parameters affect the performance of primary and secondary response. Further steps will extend the design by using an analogy to the innate system, danger signal, and memory cells.
A game-theoretic approach to optimize ad hoc networks inspired by small-world network topology
NASA Astrophysics Data System (ADS)
Tan, Mian; Yang, Tinghong; Chen, Xing; Yang, Gang; Zhu, Guoqing; Holme, Petter; Zhao, Jing
2018-03-01
Nodes in ad hoc networks are connected in a self-organized manner. Limited communication radius makes information transmit in multi-hop mode, and each forwarding needs to consume the energy of nodes. Insufficient communication radius or exhaustion of energy may cause the absence of some relay nodes and links, further breaking network connectivity. On the other hand, nodes in the network may refuse to cooperate due to objective faulty or personal selfish, hindering regular communication in the network. This paper proposes a model called Repeated Game in Small World Networks (RGSWN). In this model, we first construct ad hoc networks with small-world feature by forming "communication shortcuts" between multiple-radio nodes. Small characteristic path length reduces average forwarding times in networks; meanwhile high clustering coefficient enhances network robustness. Such networks still maintain relative low global power consumption, which is beneficial to extend the network survival time. Then we use MTTFT strategy (Mend-Tolerance Tit-for-Tat) for repeated game as a rule for the interactions between neighbors in the small-world networks. Compared with other five strategies of repeated game, this strategy not only punishes the nodes' selfishness more reasonably, but also has the best tolerance to the network failure. This work is insightful for designing an efficient and robust ad hoc network.
Persuading drivers to refrain from speeding: Effects of message sidedness and regulatory fit.
Pierro, Antonio; Giacomantonio, Mauro; Pica, Gennaro; Giannini, Anna Maria; Kruglanski, Arie W; Higgins, E Tory
2013-01-01
Building on regulatory fit theory (Higgins, 2000, 2005), we tested whether two-sided ads were more effective than one-sided ads in changing intentions toward driving behavior when message recipients were high in assessment orientation rather than locomotion orientation. In one study either a locomotion or an assessment orientation were situationally induced (Study 1) and in another study these different orientations were chronic predispositions (Study 2). As predicted, both studies found that for participants high in assessment, two-sided ads were more effective than one-sided ads, as reflected in stronger engagement with the persuasive message and stronger intentions to reduce driving speed. In contrast, for participants high in locomotion, one-sided ads were more effective than two-sided ads. There was also evidence that the fit effect on intentions to comply was mediated by strength of engagement with the message. Implications for persuasion concerning driving behaviors are discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.
A Survey on Trust Management for Mobile Ad Hoc Networks
2010-07-01
betrayal of trust. In his comments on Lagerspetz’s book titled Trust: The Tacit Demand, Lahno [24] describes the author’s view on trust as a moral...extension of AODV Zouridaki et al. (2005 ) [79] (2006) [80] Secure routing Direct observation [79][80] Reputation by secondhand information [80...the broad areas of signal processing, wireless communications, sensor and mobile ad hoc networks. He is co-editor of the book Wireless Sensor Networks
Dynamic Data Driven Applications Systems (DDDAS)
2013-03-06
INS • Chip-scale atomic clocks • Ad hoc networks • Polymorphic networks • Agile networks • Laser communications • Frequency-agile RF...atomi clocks • Ad hoc networks • Polymorphic networks • Agile networks • Laser co munications • Frequency-agile RF systems...Real-Time Doppler Wind Wind field Sensor observations Energy Estimation Atmospheric Models for On-line Planning Planning and Control
Analysis of Soldier Radio Waveform Performance in Operational Test
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
ARSENAL: A Cross Layer Architecture for Secure Resilient Tactical Mobile AdHoc Networks
2016-01-21
stations separated by 0.5 to 1 km can be coherently measured to a single mobile subscriber using LTE signaling. These are the first measurements of...undertake three parallel but inter-coupled tasks geared towards a) performing measurements via real deployments and enhancing our understanding of layer...dependencies and vulnerabilities in mobile ad hoc networks; these measurements will be on existing testbeds at The views, opinions and/or findings
ARSENAL: A Cross Layer Architecture for SecureResilient Tactical Mobile AdHoc Networks
2016-01-21
stations separated by 0.5 to 1 km can be coherently measured to a single mobile subscriber using LTE signaling. These are the first measurements of...undertake three parallel but inter-coupled tasks geared towards a) performing measurements via real deployments and enhancing our understanding of layer...dependencies and vulnerabilities in mobile ad hoc networks; these measurements will be on existing testbeds at The views, opinions and/or findings
Analytical Models of Cross-Layer Protocol Optimization in Real-Time Wireless Sensor Ad Hoc Networks
NASA Astrophysics Data System (ADS)
Hortos, William S.
The real-time interactions among the nodes of a wireless sensor network (WSN) to cooperatively process data from multiple sensors are modeled. Quality-of-service (QoS) metrics are associated with the quality of fused information: throughput, delay, packet error rate, etc. Multivariate point process (MVPP) models of discrete random events in WSNs establish stochastic characteristics of optimal cross-layer protocols. Discrete-event, cross-layer interactions in mobile ad hoc network (MANET) protocols have been modeled using a set of concatenated design parameters and associated resource levels by the MVPPs. Characterization of the "best" cross-layer designs for a MANET is formulated by applying the general theory of martingale representations to controlled MVPPs. Performance is described in terms of concatenated protocol parameters and controlled through conditional rates of the MVPPs. Modeling limitations to determination of closed-form solutions versus explicit iterative solutions for ad hoc WSN controls are examined.
Temporal patterns of scientific information-seeking on Google and Wikipedia.
Segev, Elad; Sharon, Aviv J
2017-11-01
In response to the news coverage of scientific events and to science education, people increasingly go online to get more information. This study investigates how patterns of science and technology information-seeking on Google and Wikipedia change over time, in ways that differ between "ad hoc" terms that correspond to news coverage and "cyclic" terms that correspond to the academic period. Findings show that the science and technology activity in Google and Wikipedia was significantly associated with ad hoc and cyclic patterns. While the peak activity in Google and Wikipedia largely overlapped for ad hoc terms, it mismatched for cyclic terms. The findings indicate the importance of external cues such as news media and education, and also of the online engagement process, and particularly the crucial but different role played by Google and Wikipedia in gaining science and technology knowledge. Educators and policy makers could benefit from taking into account those different patterns.
Adaptive MANET multipath routing algorithm based on the simulated annealing approach.
Kim, Sungwook
2014-01-01
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.
NASA Astrophysics Data System (ADS)
Banerjee, Koushik; Sharma, Hemant; Sengupta, Anasuya
Wireless sensor networks (WSNs) are ad hoc wireless networks that are written off as spread out structure and ad hoc deployment. Sensor networks have all the rudimentary features of ad hoc networks but to altered points—for instance, considerably lesser movement and far more energy necessities. Commonly used technology for communication is radio frequency (RF) communications. Free-space optics (FSO) is relatively new technology which has the prospective to deliver remarkable increases in network lifetime of WSN. Hybrid RF/FSO communications has been suggested to decrease power consumption by a single sensor node. It is observed that security plays a very important role for either RF WSN or hybrid RF/FSO WSN as those are vulnerable to numerous threats. In this paper, various possible attacks in RF/FSO WSN are discussed and aimed to propose some way out from those attacks.
Design of free patterns of nanocrystals with ad hoc features via templated dewetting
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aouassa, M.; Berbezier, I.; Favre, L.
Design of monodisperse ultra-small nanocrystals (NCs) into large scale patterns with ad hoc features is demonstrated. The process makes use of solid state dewetting of a thin film templated through alloy liquid metal ion source focused ion beam (LMIS-FIB) nanopatterning. The solid state dewetting initiated at the edges of the patterns controllably creates the ordering of NCs with ad hoc placement and periodicity. The NC size is tuned by varying the nominal thickness of the film while their position results from the association of film retraction from the edges of the lay out and Rayleigh-like instability. The use of ultra-highmore » resolution LMIS-FIB enables to produce monocrystalline NCs with size, periodicity, and placement tunable as well. It provides routes for the free design of nanostructures for generic applications in nanoelectronics.« less
Forming an ad-hoc nearby storage, based on IKAROS and social networking services
NASA Astrophysics Data System (ADS)
Filippidis, Christos; Cotronis, Yiannis; Markou, Christos
2014-06-01
We present an ad-hoc "nearby" storage, based on IKAROS and social networking services, such as Facebook. By design, IKAROS is capable to increase or decrease the number of nodes of the I/O system instance on the fly, without bringing everything down or losing data. IKAROS is capable to decide the file partition distribution schema, by taking on account requests from the user or an application, as well as a domain or a Virtual Organization policy. In this way, it is possible to form multiple instances of smaller capacity higher bandwidth storage utilities capable to respond in an ad-hoc manner. This approach, focusing on flexibility, can scale both up and down and so can provide more cost effective infrastructures for both large scale and smaller size systems. A set of experiments is performed comparing IKAROS with PVFS2 by using multiple clients requests under HPC IOR benchmark and MPICH2.
Applying Quantitative Approaches to the Formative Evaluation of Antismoking Campaign Messages
Parvanta, Sarah; Gibson, Laura; Forquer, Heather; Shapiro-Luft, Dina; Dean, Lorraine; Freres, Derek; Lerman, Caryn; Mallya, Giridhar; Moldovan-Johnson, Mihaela; Tan, Andy; Cappella, Joseph; Hornik, Robert
2014-01-01
This article shares an in-depth summary of a formative evaluation that used quantitative data to inform the development and selection of promotional ads for the antismoking communication component of a social marketing campaign. A foundational survey provided cross-sectional data to identify beliefs about quitting smoking that campaign messages should target, as well as beliefs to avoid. Pretesting draft ads against quantitative indicators of message effectiveness further facilitated the selection and rejection of final campaign ads. Finally, we consider lessons learned from the process of balancing quantitative methods and judgment to make formative decisions about more and less promising persuasive messages for campaigns. PMID:24817829
What is the truth? An application of the Extended Parallel Process Model to televised truth® ads.
Lavoie, Nicole R; Quick, Brian L
2013-01-01
The purpose of this study was to analyze television ads in the truth® campaign using the Extended Parallel Process Model (EPPM) as a framework. Among the ads (n = 86) analyzed, results revealed a heavy reliance on severity messages, modest attention to susceptibility messages, and no inclusion of recommended response messages in the form of self-efficacy and response efficacy. The reliance on emphasizing the health threat, without incorporating recommended response messages, is discussed with respect to the likelihood of galvanizing maladaptive responses such as psychological reactance, denial, and defensive avoidance resulting from exposure to these ads. Additionally, the unintended outcomes for secondary audiences including but not limited to stigma are considered. Implications and suggestions for practitioners and theorists are explored.
Epstein, Richard H; Dexter, Franklin; Rothman, Brian
2013-04-01
Rapid and reliable methods of text communication to mobile anesthesia care providers are important to patient care and to efficient operating room management. Anesthesia departments are implementing automated methods to send text messages to mobile devices for abnormal vital signs, clinical recommendations, quality of care, and compliance or billing issues. The most time-critical communications determine maximum acceptable latencies. We studied the reliability of several alphanumeric messaging systems to identify an appropriate technology for such use. Latencies between message initiation and delivery to 3 alphanumeric paging devices were measured over weeks. Two devices used Internet pathways outside the hospital's local network with an external paging vendor (SkyTel). The third device used only the internal hospital network (Zetron). Sequential cell phone text page latencies were examined for lag-1 autocorrelation using the runs test, with results binned by hour and by day. Message latencies subsequently were batched in successive 1-week bins for calculation of the mean and 99th percentiles of latencies. We defined acceptance criteria as a mean latency <30 seconds and no more than 1 in 200 pages (0.5%) having a latency longer than 100 seconds. Cell phone texting was used as a positive control to assure that the analysis was appropriate, because such devices have (known) poor reliability during high network activity. There was substantial correlation among latencies for sequential cell phone text messages when binned by hours (P < 0.0001), but not by days (P = 0.61). The 2 devices using Internet pathways outside the hospital's network demonstrated unacceptable performance, with 1.3% and 33% of latencies exceeding 100 seconds, respectively. The device dependent only on the internal network had a mean latency of 8 seconds, with 100% of 40,200 pages having latencies <100 seconds. The findings suggest that the network used was the deciding factor. Developers of anesthesia communication systems need to measure latencies of proposed communication pathways and devices used to deliver urgent messages to mobile users. Similar evaluation is relevant for text pagers used on an ad hoc basis for delivery of time-critical notifications. Testing over a period of hours to days is adequate only for disqualification of a candidate paging system, because acceptable results are not necessarily indicative of long-term performance. Rather, weeks of testing are required, with appropriate batching of pages for analysis.
ERIC Educational Resources Information Center
Federal Council for Science and Technology, Washington, DC. Committee on Scientific and Technical Information.
An ad hoc task group was constituted by the Committee on Scientific and Technical Information (COSATI) to: (1) delineate present and future issues issues for COSATI, (3) recommend additions or deletions in the present copyright law or in the pending revision now in Congress, and (4) recommend other short or long-term actions related to authorship…
Coverage in Heterogeneous Sensor Networks
2006-01-01
and S. Banerjee, “Node Placement for Connected Coverage in Sensor Networks,” in Proceedings of WiOpt ’03, March 2003. [10] F. Koushanfar, S...Meguerdichian, M. Potkonjak, and M. Srivastava, Cov- erage Problems in Wireless Ad-Hoc Sensor Networks, in Proceedings of the IEEE INFOCOM 01, March 2001, pp...Coverage and Connectivity of Ad Hoc Networks in Presence of Channel Randomness,” in Proceedings of the IEEE INFOCOM 05, March 2005, pp. 491–502. [16] S
Secure Mobile Distributed File System (MDFS)
2011-03-01
dissemination of data. In a mobile ad - hoc network, there are two classes of devices: content generators and content consumers. One im- plementation of...use of infrastructure mode is necessary because current Android implemen- tations do not support Mobile Ad - Hoc network without modification of the...NUMBER (include area code ) Standard Form 298 (Rev. 8–98) Prescribed by ANSI Std. Z39.18 24–3–2011 Master’s Thesis 2009-03-01—2011-03-31 Secure Mobile
Anomaly Detection for Data Reduction in an Unattended Ground Sensor (UGS) Field
2014-09-01
information (shown with solid lines in the diagram). Typically, this would be a mobile ad - hoc network (MANET). The clusters are connected to other nodes...interquartile ranges MANET mobile ad - hoc network OSUS Open Standards for Unattended Sensors TOC tactical operations center UAVs unmanned aerial vehicles...19b. TELEPHONE NUMBER (Include area code ) 301-394-1221 Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std. Z39.18 iii Contents List of
Adaptive Flow Control for Enabling Quality of Service in Tactical Ad Hoc Wireless Networks
2010-12-01
environment in wireless networks , we use sensors in the network routers to detect and respond to congestion. We use backpressure techniques... wireless mesh network . In the current approach, we used OLSR as the routing scheme. However, B.A.T.M.A.N. offers the significant advantage of being based...Control and QoS Routing in Multi-Channel Wireless Mesh Networks ,” 68-77. ACM International Symposium on Mobile Ad Hoc Networking &
Ad hoc categories and false memories: Memory illusions for categories created on-the-spot.
Soro, Jerônimo C; Ferreira, Mário B; Semin, Gün R; Mata, André; Carneiro, Paula
2017-11-01
Three experiments were designed to test whether experimentally created ad hoc associative networks evoke false memories. We used the DRM (Deese, Roediger, McDermott) paradigm with lists of ad hoc categories composed of exemplars aggregated toward specific goals (e.g., going for a picnic) that do not share any consistent set of features. Experiment 1 revealed considerable levels of false recognitions of critical words from ad hoc categories. False recognitions occurred even when the lists were presented without an organizing theme (i.e., the category's label). Experiments 1 and 2 tested whether (a) the ease of identifying the categories' themes, and (b) the lists' backward associative strength could be driving the effect. List identifiability did not correlate with false recognition, and the effect remained even when backward associative strength was controlled for. Experiment 3 manipulated the distractor items in the recognition task to address the hypothesis that the salience of unrelated items could be facilitating the occurrence of the phenomenon. The effect remained when controlling for this source of facilitation. These results have implications for assumptions made by theories of false memories, namely the preexistence of associations in the activation-monitoring framework and the central role of gist extraction in fuzzy-trace theory, while providing evidence of the occurrence of false memories for more dynamic and context-dependent knowledge structures. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Capacity-Delay Trade-Off in Collaborative Hybrid Ad-Hoc Networks with Coverage Sensing.
Chen, Lingyu; Luo, Wenbin; Liu, Chen; Hong, Xuemin; Shi, Jianghong
2017-01-26
The integration of ad hoc device-to-device (D2D) communications and open-access small cells can result in a networking paradigm called hybrid the ad hoc network, which is particularly promising in delivering delay-tolerant data. The capacity-delay performance of hybrid ad hoc networks has been studied extensively under a popular framework called scaling law analysis. These studies, however, do not take into account aspects of interference accumulation and queueing delay and, therefore, may lead to over-optimistic results. Moreover, focusing on the average measures, existing works fail to give finer-grained insights into the distribution of delays. This paper proposes an alternative analytical framework based on queueing theoretic models and physical interference models. We apply this framework to study the capacity-delay performance of a collaborative cellular D2D network with coverage sensing and two-hop relay. The new framework allows us to fully characterize the delay distribution in the transform domain and pinpoint the impacts of coverage sensing, user and base station densities, transmit power, user mobility and packet size on the capacity-delay trade-off. We show that under the condition of queueing equilibrium, the maximum throughput capacity per device saturates to an upper bound of 0.7239 λ b / λ u bits/s/Hz, where λ b and λ u are the densities of base stations and mobile users, respectively.
Strategies for generating multiple instances of common and ad hoc categories.
Vallée-Tourangeau, F; Anthony, S H; Austin, N G
1998-09-01
In a free-emission procedure participants were asked to generate instances of a given category and to report, retrospectively, the strategies that they were aware of using in retrieving instances. In two studies reported here, participants generated instances for common categories (e.g. fruit) and for ad hoc categories (e.g., things people keep in their pockets) for 90 seconds and for each category described how they had proceeded in doing so. Analysis of the protocols identified three broad classes of strategy: (1) experiential, where memories of specific or generic personal experiences involving interactions with the category instances acted as cues; (2) semantic, where a consideration of abstract conceptual characteristics of a category were employed to retrieve category exemplars; (3) unmediated, where instances were effortlessly retrieved without mediating cognitions of which subjects were aware. Experiential strategies outnumbered semantic strategies (on average 4 to 1) not only for ad hoc categories but also for common categories. This pattern was noticeably reversed for ad hoc categories that subjects were unlikely to have experienced personally (e.g. things sold on the black market in Russia). Whereas more traditional accounts of semantic memory have favoured decontextualised abstract representations of category knowledge, to the extent that mode of access informs us of knowledge structures, our data suggest that category knowledge is significantly grounded in terms of everyday contexts where category instances are encountered.
Capacity-Delay Trade-Off in Collaborative Hybrid Ad-Hoc Networks with Coverage Sensing
Chen, Lingyu; Luo, Wenbin; Liu, Chen; Hong, Xuemin; Shi, Jianghong
2017-01-01
The integration of ad hoc device-to-device (D2D) communications and open-access small cells can result in a networking paradigm called hybrid the ad hoc network, which is particularly promising in delivering delay-tolerant data. The capacity-delay performance of hybrid ad hoc networks has been studied extensively under a popular framework called scaling law analysis. These studies, however, do not take into account aspects of interference accumulation and queueing delay and, therefore, may lead to over-optimistic results. Moreover, focusing on the average measures, existing works fail to give finer-grained insights into the distribution of delays. This paper proposes an alternative analytical framework based on queueing theoretic models and physical interference models. We apply this framework to study the capacity-delay performance of a collaborative cellular D2D network with coverage sensing and two-hop relay. The new framework allows us to fully characterize the delay distribution in the transform domain and pinpoint the impacts of coverage sensing, user and base station densities, transmit power, user mobility and packet size on the capacity-delay trade-off. We show that under the condition of queueing equilibrium, the maximum throughput capacity per device saturates to an upper bound of 0.7239 λb/λu bits/s/Hz, where λb and λu are the densities of base stations and mobile users, respectively. PMID:28134769
Enhancing the effectiveness of antismoking messages via self-congruent appeals.
Chang, Chingching
2009-01-01
A self-congruent effect model was applied to understand adolescents' responses to antismoking advertising that referred to the self or others. Experiment 1 showed that self-referring ads generated more negative smoking attitudes than other-referring ads among adolescents with independent self-construals, whereas other-referring ads generated more negative smoking attitudes than self-referring ads among adolescents with interdependent self-construals. A survey further showed that smokers rated themselves higher on a measure of independent self-construal than nonsmokers. Experiment 2 then found that self-referring ads are more effective than other-referring ads for smokers, who have independent self-construals. Findings supported the idea that health communication campaign designers can maximize message effectiveness by developing different messages for different target segments of the population based on their self-construals.
Cosentino, Erica; Baggio, Giosuè; Kontinen, Jarmo; Werning, Markus
2017-01-01
Contemporary semantic theories can be classified along two dimensions: (i) the way and time-course in which contextual factors influence sentence truth-conditions; and (ii) whether and to what extent comprehension involves sensory, motor and emotional processes. In order to explore this theoretical space, our ERP study investigates the time-course of the interaction between the lexically specified telic component of a noun (the function of the object to which the noun refers to, e.g., a funnel is generally used to pour liquids into containers) and an ad-hoc affordance contextually induced by the situation described in the discourse. We found that, if preceded by a neutral discourse context, a verb incongruent with the noun's telic component as in “She uses the funnel to hang her coat” elicited an enhanced N400 compared to a congruent verb as in “She uses the funnel to pour water into a container.” However, if the situation introduced in the preceding discourse induced a new function for the object as an ad-hoc affordance (e.g., the funnel is glued to the wall and the agent wants to hang the coat), we observed a crossing-over regarding the direction of the N400 effect: comparing the ad-hoc affordance-inducing context with the neutral context, the N400 for the incongruent verb was significantly reduced, whereas the N400 for the congruent verb was significantly enhanced. We explain these results as a consequence of the incorporation of the contextually triggered ad-hoc affordance into the meaning of the noun. Combining these results with an analysis of semantic similarity values between test sentences and contexts, we argue that one possibility is that the incorporation of an ad-hoc affordance may be explained on the basis of the mental simulation of concurrent motor information. PMID:28603506
Cosentino, Erica; Baggio, Giosuè; Kontinen, Jarmo; Werning, Markus
2017-01-01
Contemporary semantic theories can be classified along two dimensions: (i) the way and time-course in which contextual factors influence sentence truth-conditions; and (ii) whether and to what extent comprehension involves sensory, motor and emotional processes. In order to explore this theoretical space, our ERP study investigates the time-course of the interaction between the lexically specified telic component of a noun (the function of the object to which the noun refers to, e.g., a funnel is generally used to pour liquids into containers) and an ad-hoc affordance contextually induced by the situation described in the discourse. We found that, if preceded by a neutral discourse context, a verb incongruent with the noun's telic component as in "She uses the funnel to hang her coat" elicited an enhanced N400 compared to a congruent verb as in "She uses the funnel to pour water into a container." However, if the situation introduced in the preceding discourse induced a new function for the object as an ad-hoc affordance (e.g., the funnel is glued to the wall and the agent wants to hang the coat), we observed a crossing-over regarding the direction of the N400 effect: comparing the ad-hoc affordance-inducing context with the neutral context, the N400 for the incongruent verb was significantly reduced, whereas the N400 for the congruent verb was significantly enhanced. We explain these results as a consequence of the incorporation of the contextually triggered ad-hoc affordance into the meaning of the noun. Combining these results with an analysis of semantic similarity values between test sentences and contexts, we argue that one possibility is that the incorporation of an ad-hoc affordance may be explained on the basis of the mental simulation of concurrent motor information.
Ad hoc instrumentation methods in ecological studies produce highly biased temperature measurements
Terando, Adam J.; Youngsteadt, Elsa; Meineke, Emily K.; Prado, Sara G.
2017-01-01
In light of global climate change, ecological studies increasingly address effects of temperature on organisms and ecosystems. To measure air temperature at biologically relevant scales in the field, ecologists often use small, portable temperature sensors. Sensors must be shielded from solar radiation to provide accurate temperature measurements, but our review of 18 years of ecological literature indicates that shielding practices vary across studies (when reported at all), and that ecologists often invent and construct ad hoc radiation shields without testing their efficacy. We performed two field experiments to examine the accuracy of temperature observations from three commonly used portable data loggers (HOBO Pro, HOBO Pendant, and iButton hygrochron) housed in manufactured Gill shields or ad hoc, custom‐fabricated shields constructed from everyday materials such as plastic cups. We installed this sensor array (five replicates of 11 sensor‐shield combinations) at weather stations located in open and forested sites. HOBO Pro sensors with Gill shields were the most accurate devices, with a mean absolute error of 0.2°C relative to weather stations at each site. Error in ad hoc shield treatments ranged from 0.8 to 3.0°C, with the largest errors at the open site. We then deployed one replicate of each sensor‐shield combination at five sites that varied in the amount of urban impervious surface cover, which presents a further shielding challenge. Bias in sensors paired with ad hoc shields increased by up to 0.7°C for every 10% increase in impervious surface. Our results indicate that, due to variable shielding practices, the ecological literature likely includes highly biased temperature data that cannot be compared directly across studies. If left unaddressed, these errors will hinder efforts to predict biological responses to climate change. We call for greater standardization in how temperature data are recorded in the field, handled in analyses, and reported in publications.
Wu, Wann-Yih; Linn, Cho Thwe; Fu, Chen-Su; Sukoco, Badri Munir
2012-01-01
This study examined the effects of endorsers, message framing, and rewards on consumers' responses toward dietary supplement advertisements in terms of ad liking and ad believability, attitude toward the advertisement, attitude toward the brand, and behavioral intention. The results of 2 × 2 × 2 factorial design show that viewers respond differently to different types of endorser, message framing, and rewards. Rewards have moderate influences on consumers' ad liking when combined with different framed messages and endorsers. Endorsers, message framing, and rewards are interrelated; it is notable that respondents express more ad liking when celebrity endorser, positive framing, and extrinsic reward are used in combination. The authors found that ad liking and ad believability have an effect on attitude toward the advertisement and the brand. In addition, the authors found that (a) attitude toward the advertisement has relations with attitude toward the brand and behavioral intention and (b) attitude toward the brand has a significant influence on behavioral intention. These results can also be useful for marketers with regard to developing and implementing their marketing activities to specific customer segment.
Cooper, Nicole; Tompson, Steven; O'Donnell, Matthew B; Vettel, Jean M; Bassett, Danielle S; Falk, Emily B
2018-04-01
Worldwide, tobacco use is the leading cause of preventable death and illness. One common strategy for reducing the prevalence of cigarette smoking and other health risk behaviors is the use of graphic warning labels (GWLs). This has led to widespread interest from the perspective of health psychology in understanding the mechanisms of GWL effectiveness. Here we investigated differences in how the brain responds to negative, graphic warning label-inspired antismoking ads and neutral control ads, and we probed how this response related to future behavior. A group of smokers (N = 45) viewed GWL-inspired and control antismoking ads while undergoing fMRI, and their smoking behavior was assessed before and one month after the scan. We examined neural coherence between two regions in the brain's valuation network, the medial prefrontal cortex (MPFC) and ventral striatum (VS). We found that greater neural coherence in the brain's valuation network during GWL ads (relative to control ads) preceded later smoking reduction. Our results suggest that the integration of information about message value may be key for message influence. Understanding how the brain responds to health messaging and relates to future behavior could ultimately contribute to the design of effective messaging campaigns, as well as more broadly to theories of message effects and persuasion across domains. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
2014-02-26
set of anomaly detection rules 62 I.-R. Chen et al. / Ad Hoc Networks 19 (2014) 59–74 Author’s personal copy including the interval rule (for...deficiencies in anomaly detection (e.g., imperfection of rules) by a false negative probability (PHfn) of misidentifying an unhealthy node as a...multimedia servers, Multimedia Syst. 8 (2) (2000) 83–91. [53] R. Mitchell, I.R. Chen, Adaptive intrusion detection for unmanned aircraft systems based on
ERIC Educational Resources Information Center
Congress of the U.S., Washington, DC. House Committee on Merchant Marine and Fisheries.
The publication consists of Congressional hearings before the Ad Hoc Committee on Maritime Education and Training: (1) June 26, 1974 hearing pertaining to officer requirements and (2) November 19, 1974 hearing on maritime education regarding safety at sea. Estimated cost per graduate for the U. S. Merchant Marine 1973 class was $31,100. Supply and…
Mapping Ad Hoc Communications Network of a Large Number Fixed-Wing UAV Swarm
2017-03-01
partitioned sub-swarms. The work covered in this thesis is to build a model of the NPS swarm’s communication network in ns-3 simulation software and use...partitioned sub- swarms. The work covered in this thesis is to build a model of the NPS swarm’s communication network in ns-3 simulation software and...NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS MAPPING AD HOC COMMUNICATIONS NETWORK OF A LARGE NUMBER FIXED-WING UAV SWARM by Alexis
2007-04-01
for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data...Control Organization NRL Navy Research Laboratory nrtPS Non-real- time Polling Services OFDM Orthogonal frequency division multiplex OFDMA...Routeur IDentifier RTG RTO Task Group RTO Research & Technology Organization rtPS Real- time Polling Services SC Single-carrier modulation
Rogers, Patrick; Erdal, Selnur; Santangelo, Jennifer; Liu, Jianhua; Schuster, Dara; Kamal, Jyoti
2008-11-06
The Ohio State University Medical Center (OSUMC) Information Warehouse (IW) is a comprehensive data warehousing facility incorporating operational, clinical, and biological data sets from multiple enterprise system. It is common for users of the IW to request complex ad-hoc queries that often require significant intervention by data analyst. In response to this challenge, we have designed a workflow that leverages synthesized data elements to support such queries in an more timely, efficient manner.
GAPR2: A DTN Routing Protocol for Communications in Challenged, Degraded, and Denied Environments
2015-09-01
Transmission Speed Vs. Latency Figure 4.7: Helsinki Simulation Set 2, High Network Load and Small Buffers Analysis of Delivery Ratio in Helsinki Simulation...ipnsig.org/. [17] MANET routing, class notes for CS4554: Network modeling and analysis . 119 [18] S. Basagni et al. Mobile ad hoc networking . John...Wiley & Sons, 2004. [19] E. Royer et al. A review of current routing protocols for ad hoc mobile wireless networks . Personal Communications, IEEE, 6(2
ERIC Educational Resources Information Center
Morin, Emma
Theme I of the Ad Hoc Conference on the Education of Migrants was "measures to improve the position of the immigrant and his family at the time of arrival in the host country (including measures taken in the sending country on behalf of those intending to emigrate), primarily in respect of their educational circumstances". This report…
Knox, Emily C L; Webb, Oliver J; Esliger, Dale W; Biddle, Stuart J H; Sherar, Lauren B
2014-04-01
The promotion of physical activity (PA) guidelines to the general public is an important issue that lacks empirical investigation. PA campaigns often feature participation thresholds that cite PA guidelines verbatim [e.g., 150 min/week moderate-to-vigorous physical activity (MVPA)]. Some campaigns instead prefer to use generic PA messages (e.g., do as much MVPA as possible). 'Thresholds' may disrupt understanding of the health benefits of modest PA participation. This study examined the perception of health benefits of PA after exposure to PA messages that did and did not contain a duration threshold. Brief structured interviews were conducted with a convenience sample of adults (n = 1100). Participants received a threshold message (150 min/week MVPA), a message that presented the threshold as a minimum; a generic message or no message. Participants rated perceived health effects of seven PA durations. One-way analyses of variance with post hoc tests for group differences were used to assess raw perception ratings for each duration of PA. Recipients of all three messages held more positive perceptions of >150 min/week of MVPA relative to those not receiving any message. For MVPA durations <150 min/week, the generic PA message group perceived the greatest health benefits. Those receiving the threshold message tended to have the least positive perceptions of durations <150 min/week. Threshold messages were associated with lower perceived health benefits for modest PA durations. Campaigns based on threshold messages may be limited when promoting small PA increases at a population level.
An, Soontae; Kang, Hannah
2011-01-01
This study analyzed direct-to-consumer (DTC) print ads for stigmatized illnesses from 1998 to 2008. Attribution theory and recategorization theory were used as theoretical frames to assess whether those DTC ads contained message components to reduce stigma. DTC ads for 10 stigmatized illnesses in National Geographic, Better Homes and Gardens, Ladies' Home Journal, and Time were analyzed for the presence of onset controllability, offset controllability, and recategorization. Results showed that only 3.7% of ads offered the three message components together and, in fact, 21% of the ads did not contain any of the stigma-reducing message elements. Recategorization cue was the most prevalent component, while cues for onset and offset controllability were relatively less frequent, indicating the lack of educational components. Copyright © Taylor & Francis Group, LLC
Seelig, David; Wang, An-Li; Jagannathan, Kanchana; Jaganathan, Kanchana; Loughead, James W; Blady, Shira J; Childress, Anna Rose; Romer, Daniel; Langleben, Daniel D
2014-01-01
Greater sensory stimulation in advertising has been postulated to facilitate attention and persuasion. For this reason, video ads promoting health behaviors are often designed to be high in "message sensation value" (MSV), a standardized measure of sensory intensity of the audiovisual and content features of an ad. However, our previous functional Magnetic Resonance Imaging (fMRI) study showed that low MSV ads were better remembered and produced more prefrontal and temporal and less occipital cortex activation, suggesting that high MSV may divert cognitive resources from processing ad content. The present study aimed to determine whether these findings from anti-smoking ads generalize to other public health topics, such as safe sex. Thirty-nine healthy adults viewed high- and low MSV ads promoting safer sex through condom use, during an fMRI session. Recognition memory of the ads was tested immediately and 3 weeks after the session. We found that low MSV condom ads were better remembered than the high MSV ads at both time points and replicated the fMRI patterns previously reported for the anti-smoking ads. Occipital and superior temporal activation was negatively related to the attitudes favoring condom use (see Condom Attitudes Scale, Methods and Materials section). Psychophysiological interaction (PPI) analysis of the relation between occipital and fronto-temporal (middle temporal and inferior frontal gyri) cortices revealed weaker negative interactions between occipital and fronto-temporal cortices during viewing of the low MSV that high MSV ads. These findings confirm that the low MSV video health messages are better remembered than the high MSV messages and that this effect generalizes across public health domains. The greater engagement of the prefrontal and fronto-temporal cortices by low MSV ads and the greater occipital activation by high MSV ads suggest that that the "attention-grabbing" high MSV format could impede the learning and retention of public health messages.
Jaganathan, Kanchana; Loughead, James W.; Blady, Shira J.; Childress, Anna Rose; Romer, Daniel; Langleben, Daniel D.
2014-01-01
Greater sensory stimulation in advertising has been postulated to facilitate attention and persuasion. For this reason, video ads promoting health behaviors are often designed to be high in “message sensation value” (MSV), a standardized measure of sensory intensity of the audiovisual and content features of an ad. However, our previous functional Magnetic Resonance Imaging (fMRI) study showed that low MSV ads were better remembered and produced more prefrontal and temporal and less occipital cortex activation, suggesting that high MSV may divert cognitive resources from processing ad content. The present study aimed to determine whether these findings from anti-smoking ads generalize to other public health topics, such as safe sex. Thirty-nine healthy adults viewed high- and low MSV ads promoting safer sex through condom use, during an fMRI session. Recognition memory of the ads was tested immediately and 3 weeks after the session. We found that low MSV condom ads were better remembered than the high MSV ads at both time points and replicated the fMRI patterns previously reported for the anti-smoking ads. Occipital and superior temporal activation was negatively related to the attitudes favoring condom use (see Condom Attitudes Scale, Methods and Materials section). Psychophysiological interaction (PPI) analysis of the relation between occipital and fronto-temporal (middle temporal and inferior frontal gyri) cortices revealed weaker negative interactions between occipital and fronto-temporal cortices during viewing of the low MSV that high MSV ads. These findings confirm that the low MSV video health messages are better remembered than the high MSV messages and that this effect generalizes across public health domains. The greater engagement of the prefrontal and fronto-temporal cortices by low MSV ads and the greater occipital activation by high MSV ads suggest that that the “attention-grabbing” high MSV format could impede the learning and retention of public health messages. PMID:25409187
Ad Hoc Information Extraction for Clinical Data Warehouses.
Dietrich, Georg; Krebs, Jonathan; Fette, Georg; Ertl, Maximilian; Kaspar, Mathias; Störk, Stefan; Puppe, Frank
2018-05-01
Clinical Data Warehouses (CDW) reuse Electronic health records (EHR) to make their data retrievable for research purposes or patient recruitment for clinical trials. However, much information are hidden in unstructured data like discharge letters. They can be preprocessed and converted to structured data via information extraction (IE), which is unfortunately a laborious task and therefore usually not available for most of the text data in CDW. The goal of our work is to provide an ad hoc IE service that allows users to query text data ad hoc in a manner similar to querying structured data in a CDW. While search engines just return text snippets, our systems also returns frequencies (e.g. how many patients exist with "heart failure" including textual synonyms or how many patients have an LVEF < 45) based on the content of discharge letters or textual reports for special investigations like heart echo. Three subtasks are addressed: (1) To recognize and to exclude negations and their scopes, (2) to extract concepts, i.e. Boolean values and (3) to extract numerical values. We implemented an extended version of the NegEx-algorithm for German texts that detects negations and determines their scope. Furthermore, our document oriented CDW PaDaWaN was extended with query functions, e.g. context sensitive queries and regex queries, and an extraction mode for computing the frequencies for Boolean and numerical values. Evaluations in chest X-ray reports and in discharge letters showed high F1-scores for the three subtasks: Detection of negated concepts in chest X-ray reports with an F1-score of 0.99 and in discharge letters with 0.97; of Boolean values in chest X-ray reports about 0.99, and of numerical values in chest X-ray reports and discharge letters also around 0.99 with the exception of the concept age. The advantages of an ad hoc IE over a standard IE are the low development effort (just entering the concept with its variants), the promptness of the results and the adaptability by the user to his or her particular question. Disadvantage are usually lower accuracy and confidence.This ad hoc information extraction approach is novel and exceeds existing systems: Roogle [1] extracts predefined concepts from texts at preprocessing and makes them retrievable at runtime. Dr. Warehouse [2] applies negation detection and indexes the produced subtexts which include affirmed findings. Our approach combines negation detection and the extraction of concepts. But the extraction does not take place during preprocessing, but at runtime. That provides an ad hoc, dynamic, interactive and adjustable information extraction of random concepts and even their values on the fly at runtime. We developed an ad hoc information extraction query feature for Boolean and numerical values within a CDW with high recall and precision based on a pipeline that detects and removes negations and their scope in clinical texts. Schattauer GmbH.
Quick, Brian L
2013-01-01
The present study tests to see whether perceived message sensation value reduces psychological reactance within the context of anti-marijuana ads for television. After controlling for sensation seeking, biological sex, and marijuana use, the results indicate that message novelty is negatively associated with a freedom threat, whereas dramatic impact and emotional arousal were not associated with the antecedent to reactance. Results support the use of novel messages in future ads while at the same time offer an explanation to the challenges involved in creating effective anti-marijuana ads. Overall, the results provide partial support for the dominant thought disruption hypothesis and are discussed with an emphasis on the theoretical and practical implications for health communication researchers and practitioners.
Emery, R J; Sprau, D D; Morecook, R C
2008-11-01
Experience gained during a field training exercise with a Medical Reserve Corps unit on the screening of large groups of individuals for possible contamination with radioactive material revealed that while exercise participants were generally attentive to the proper use of protective equipment and detectors, they tended to overlook important basic risk communications aspects. For example, drill participants did not actively communicate with the persons waiting in line for screening, a step which would provide re-assurance, possibly minimize apprehension, and would clarify expectations. When questioned on this issue of risk communication, drill participants were often able to craft ad hoc messages, but the messages were inconsistent and likely would not have significantly helped diminish anxiety and maintain crowd control. Similar difficulties were encountered regarding messaging for persons determined to be contaminated, those departing the screening center, and those to be delivered to the media. Based on these experiences, the need for a suggested list of risk communication points was identified. To address this need, a set of risk communication templates were developed that focused on the issues likely to be encountered in a mass screening event. The points include issues such as the importance of remaining calm, steps for minimizing possible intake or uptake, considerations for those exhibiting acute injuries, expected screening wait times, the process to be followed and the information to be collected, the process to be undertaken for those exhibiting contamination, and symptoms to watch for after departure. Drill participants indicated in follow-up discussions that such pre-established risk communication templates would serve to enhance their ability to assist in times of emergency and noted the potential broader applicably of the approach for use in responses for other disasters types as well.
Comello, Maria Leonora G
2013-01-01
Two national campaigns--My Anti-Drug and Above the Influence--have been implemented to prevent youth substance use. Although Above the Influence was conceptualized as a major shift in messaging from My Anti-Drug, no studies have reported head-to-head tests of message effects on behavior-relevant outcomes. An experiment was conducted in which participants viewed ads from one of the campaigns and answered questions about ad appeal and emotional tone; campaign appeal; and marijuana-related beliefs. Compared to My Anti-Drug ads, Above the Influence ads were associated with more positive emotional tone and with lower perceptions of marijuana risk. Implications for message design and evaluation are discussed.
NASA Astrophysics Data System (ADS)
Vadivel, R.; Bhaskaran, V. Murali
2010-10-01
The main reason for packet loss in ad hoc networks is the link failure or node failure. In order to increase the path stability, it is essential to distinguish and moderate the failures. By knowing individual link stability along a path, path stability can be identified. In this paper, we develop an adaptive reliable routing protocol using combined link stability estimation for mobile ad hoc networks. The main objective of this protocol is to determine a Quality of Service (QoS) path along with prolonging the network life time and to reduce the packet loss. We calculate a combined metric for a path based on the parameters Link Expiration Time, Node Remaining Energy and Node Velocity and received signal strength to predict the link stability or lifetime. Then, a bypass route is established to retransmit the lost data, when a link failure occurs. By simulation results, we show that the proposed reliable routing protocol achieves high delivery ratio with reduced delay and packet drop.
An Optimal CDS Construction Algorithm with Activity Scheduling in Ad Hoc Networks
Penumalli, Chakradhar; Palanichamy, Yogesh
2015-01-01
A new energy efficient optimal Connected Dominating Set (CDS) algorithm with activity scheduling for mobile ad hoc networks (MANETs) is proposed. This algorithm achieves energy efficiency by minimizing the Broadcast Storm Problem [BSP] and at the same time considering the node's remaining energy. The Connected Dominating Set is widely used as a virtual backbone or spine in mobile ad hoc networks [MANETs] or Wireless Sensor Networks [WSN]. The CDS of a graph representing a network has a significant impact on an efficient design of routing protocol in wireless networks. Here the CDS is a distributed algorithm with activity scheduling based on unit disk graph [UDG]. The node's mobility and residual energy (RE) are considered as parameters in the construction of stable optimal energy efficient CDS. The performance is evaluated at various node densities, various transmission ranges, and mobility rates. The theoretical analysis and simulation results of this algorithm are also presented which yield better results. PMID:26221627
On knowledge transfer management as a learning process for ad hoc teams
NASA Astrophysics Data System (ADS)
Iliescu, D.
2017-08-01
Knowledge management represents an emerging domain becoming more and more important. Concepts like knowledge codification and personalisation, knowledge life-cycle, social and technological dimensions, knowledge transfer and learning management are integral parts. Focus goes here in the process of knowledge transfer for the case of ad hoc teams. The social dimension of knowledge transfer plays an important role. No single individual actors involved in the process, but a collective one, representing the organisation. It is critically important for knowledge to be managed from the life-cycle point of view. A complex communication network needs to be in place to supports the process of knowledge transfer. Two particular concepts, the bridge tie and transactive memory, would eventually enhance the communication. The paper focuses on an informational communication platform supporting the collaborative work on knowledge transfer. The platform facilitates the creation of a topic language to be used in knowledge modelling, storage and reuse, by the ad hoc teams.
On Trust Evaluation in Mobile Ad Hoc Networks
NASA Astrophysics Data System (ADS)
Nguyen, Dang Quan; Lamont, Louise; Mason, Peter C.
Trust has been considered as a social relationship between two individuals in human society. But, as computer science and networking have succeeded in using computers to automate many tasks, the concept of trust can be generalized to cover the reliability and relationships of non-human interaction, such as, for example, information gathering and data routing. This paper investigates the evaluation of trust in the context of ad hoc networks. Nodes evaluate each other’s behaviour based on observables. A node then decides whether to trust another node to have certain innate abilities. We show how accurate such an evaluation could be. We also provide the minimum number of observations required to obtain an accurate evaluation, a result that indicates that observation-based trust in ad hoc networks will remain a challenging problem. The impact of making networking decisions using trust evaluation on the network connectivity is also examined. In this manner, quantitative decisions can be made concerning trust-based routing with the knowledge of the potential impact on connectivity.
NASA Astrophysics Data System (ADS)
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.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Dr. Li; Cui, Xiaohui; Cemerlic, Alma
Ad hoc networks are very helpful in situations when no fixed network infrastructure is available, such as natural disasters and military conflicts. In such a network, all wireless nodes are equal peers simultaneously serving as both senders and routers for other nodes. Therefore, how to route packets through reliable paths becomes a fundamental problems when behaviors of certain nodes deviate from wireless ad hoc routing protocols. We proposed a novel Dirichlet reputation model based on Bayesian inference theory which evaluates reliability of each node in terms of packet delivery. Our system offers a way to predict and select a reliablemore » path through combination of first-hand observation and second-hand reputation reports. We also proposed moving window mechanism which helps to adjust ours responsiveness of our system to changes of node behaviors. We integrated the Dirichlet reputation into routing protocol of wireless ad hoc networks. Our extensive simulation indicates that our proposed reputation system can improve good throughput of the network and reduce negative impacts caused by misbehaving nodes.« less
Sputnik: ad hoc distributed computation.
Völkel, Gunnar; Lausser, Ludwig; Schmid, Florian; Kraus, Johann M; Kestler, Hans A
2015-04-15
In bioinformatic applications, computationally demanding algorithms are often parallelized to speed up computation. Nevertheless, setting up computational environments for distributed computation is often tedious. Aim of this project were the lightweight ad hoc set up and fault-tolerant computation requiring only a Java runtime, no administrator rights, while utilizing all CPU cores most effectively. The Sputnik framework provides ad hoc distributed computation on the Java Virtual Machine which uses all supplied CPU cores fully. It provides a graphical user interface for deployment setup and a web user interface displaying the current status of current computation jobs. Neither a permanent setup nor administrator privileges are required. We demonstrate the utility of our approach on feature selection of microarray data. The Sputnik framework is available on Github http://github.com/sysbio-bioinf/sputnik under the Eclipse Public License. hkestler@fli-leibniz.de or hans.kestler@uni-ulm.de Supplementary data are available at Bioinformatics online. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
A multihop key agreement scheme for wireless ad hoc networks based on channel characteristics.
Hao, Zhuo; Zhong, Sheng; Yu, Nenghai
2013-01-01
A number of key agreement schemes based on wireless channel characteristics have been proposed recently. However, previous key agreement schemes require that two nodes which need to agree on a key are within the communication range of each other. Hence, they are not suitable for multihop wireless networks, in which nodes do not always have direct connections with each other. In this paper, we first propose a basic multihop key agreement scheme for wireless ad hoc networks. The proposed basic scheme is resistant to external eavesdroppers. Nevertheless, this basic scheme is not secure when there exist internal eavesdroppers or Man-in-the-Middle (MITM) adversaries. In order to cope with these adversaries, we propose an improved multihop key agreement scheme. We show that the improved scheme is secure against internal eavesdroppers and MITM adversaries in a single path. Both performance analysis and simulation results demonstrate that the improved scheme is efficient. Consequently, the improved key agreement scheme is suitable for multihop wireless ad hoc networks.
NASA Astrophysics Data System (ADS)
Leroy, Norah
2017-08-01
This paper addresses the theme of social inclusion through language learning. The focus is on an ad-hoc tutoring scheme set up between newly arrived British migrant pupils and French monolingual pupils in a small secondary school in the south-west of France. Though the original objective of this tutoring scheme was to improve the English skills of the younger pupils, feedback reports indicated that it also had a positive impact on the relationship between the British migrant pupils and their French peers. Teachers believed that those involved participated more fully in class, and appeared more self-assured and generally happy thanks to the interpersonal relationships this scheme helped to forge. This study demonstrates the necessity of analysing the socio-cultural context migrants may find themselves in, in order to identify potential challenges. The ad-hoc tutoring scheme described here is an example of how language learning can support the integration and inclusion of "new generation" migrants into everyday school life.
Performance Evaluation of AODV with Blackhole Attack
NASA Astrophysics Data System (ADS)
Dara, Karuna
2010-11-01
A Mobile Ad Hoc Network (MANET) is a temporary network set up by a wireless mobile computers moving arbitrary in the places that have no network infrastructure. These nodes maintain connectivity in a decentralized manner. Since the nodes communicate with each other, they cooperate by forwarding data packets to other nodes in the network. Thus the nodes find a path to the destination node using routing protocols. However, due to security vulnerabilities of the routing protocols, mobile ad-hoc networks are unprotected to attacks of the malicious nodes. One of these attacks is the Black Hole Attack against network integrity absorbing all data packets in the network. Since the data packets do not reach the destination node on account of this attack, data loss will occur. In this paper, we simulated the black hole attack in various mobile ad-hoc network scenarios using AODV routing protocol of MANET and have tried to find a effect if number of nodes are increased with increase in malicious nodes.
A Multihop Key Agreement Scheme for Wireless Ad Hoc Networks Based on Channel Characteristics
Yu, Nenghai
2013-01-01
A number of key agreement schemes based on wireless channel characteristics have been proposed recently. However, previous key agreement schemes require that two nodes which need to agree on a key are within the communication range of each other. Hence, they are not suitable for multihop wireless networks, in which nodes do not always have direct connections with each other. In this paper, we first propose a basic multihop key agreement scheme for wireless ad hoc networks. The proposed basic scheme is resistant to external eavesdroppers. Nevertheless, this basic scheme is not secure when there exist internal eavesdroppers or Man-in-the-Middle (MITM) adversaries. In order to cope with these adversaries, we propose an improved multihop key agreement scheme. We show that the improved scheme is secure against internal eavesdroppers and MITM adversaries in a single path. Both performance analysis and simulation results demonstrate that the improved scheme is efficient. Consequently, the improved key agreement scheme is suitable for multihop wireless ad hoc networks. PMID:23766725
76 FR 70984 - National Assessment Governing Board; Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-16
... be discussed/disclosed in an open meeting. Premature disclosure of these secure test items and... Education, National Assessment Governing Board. ACTION: Notice of Open and Closed Meeting Sessions. SUMMARY... Hoc, Assessment Development, and Executive Committee. Meetings Ad Hoc Committee: Open Session: 8:30 a...
Social and Religious Factors in Adolescents' Drug Use
ERIC Educational Resources Information Center
Jones, Sandra C.; Rossiter, John R.
2009-01-01
The original purpose of this study was to test several types of anti-cannabis messages. Analysis of the results led to a second, post hoc purpose: to explain why pre-intervention substance usage rates varied so greatly between the sampled schools. Participants were Australian ninth-grade students at a state government high school and a…
Organizational culture during the accident response process
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shurberg, D.A.; Haber, S.B.
1992-01-01
The ability of an organization to effectively move from an anticipatory to an ad hoc strategy may well depend on the organization having the ability to balance these two apparently dichotomous cultural styles. The organization which is most capable of making the necessary transition in an optimal manner may well exhibit some aspects of both cultural styles during normal operations. Data collected at one NPP does exhibit this pattern of results, with the organization exhibiting a clear hierarchical chain of command and perceived conventional behavioral expectations as well as exhibiting a more decentralized and collegial approach to decisionmaking, a teammore » work orientation, and informal communications. Thus, it is expected that this organization possesses the capabilities to make a successful transition from an anticipatory to an ad hoc strategy. Data collected at a second NPP more strongly exhibits the traditional style suggested as being important during the anticipatory strategy, with more formal communications and bureaucratically controlled decision-making. This organization may experience difficulty if faced with the need to make a transition from an anticipatory to an ad hoc strategy. These conclusions are further validated based on observation of Emergency Preparedness Exercise Inspections, which suggest that the more anticipatory types of behaviors actually inhibit successful performance during an ad hoc response. The final validation of these hypotheses needs to be demonstrated with cultural data collected during emergency simulations. The mechanism to obtain such data during these types of situations is an area for future research.« less
Organizational culture during the accident response process
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shurberg, D.A.; Haber, S.B.
1992-08-01
The ability of an organization to effectively move from an anticipatory to an ad hoc strategy may well depend on the organization having the ability to balance these two apparently dichotomous cultural styles. The organization which is most capable of making the necessary transition in an optimal manner may well exhibit some aspects of both cultural styles during normal operations. Data collected at one NPP does exhibit this pattern of results, with the organization exhibiting a clear hierarchical chain of command and perceived conventional behavioral expectations as well as exhibiting a more decentralized and collegial approach to decisionmaking, a teammore » work orientation, and informal communications. Thus, it is expected that this organization possesses the capabilities to make a successful transition from an anticipatory to an ad hoc strategy. Data collected at a second NPP more strongly exhibits the traditional style suggested as being important during the anticipatory strategy, with more formal communications and bureaucratically controlled decision-making. This organization may experience difficulty if faced with the need to make a transition from an anticipatory to an ad hoc strategy. These conclusions are further validated based on observation of Emergency Preparedness Exercise Inspections, which suggest that the more anticipatory types of behaviors actually inhibit successful performance during an ad hoc response. The final validation of these hypotheses needs to be demonstrated with cultural data collected during emergency simulations. The mechanism to obtain such data during these types of situations is an area for future research.« less
Clement, T; Brown, J; Morrison, J; Nestel, D
2016-05-01
General practice registrars in Australia undertake most of their vocational training in accredited general practices. They typically see patients alone from the start of their community-based training and are expected to seek timely ad hoc support from their supervisor. Such ad hoc encounters are a mechanism for ensuring patient safety, but also provide an opportunity for learning and teaching. Wenger's (Communities of practice: learning, meaning, and identity. Cambridge University Press, New York, 1998) social theory of learning ('communities of practice') guided a secondary analysis of audio-recordings of ad hoc encounters. Data from one encounter is re-presented as an extended sequence to maintain congruence with the theoretical perspective and enhance vicariousness. An interpretive commentary communicates key features of Wenger's theory and highlights the researchers' interpretations. We argue that one encounter can reveal universal understandings of clinical supervision and that the process of naturalistic generalisation allows readers to transfer others' experiences to their own contexts. The paper raises significant analytic, interpretive, and representational issues. We highlight that report writing is an important, but infrequently discussed, part of research design. We discuss the challenges of supporting the learning and teaching that arises from adopting a socio-cultural lens and argue that such a perspective importantly captures the complex range of issues that work-based practitioners have to grapple with. This offers a challenge to how we research and seek to influence work-based learning and teaching in health care settings.
Blanc, Nathalie; Brigaud, Emmanuelle
2014-01-01
This study tested the effect of humor in one particular type of print advertisement: the preventive health ads for three topics (alcohol, tobacco, obesity). Previous research using commercial ads demonstrated that individuals' attention is spontaneously attracted by humor, leading to a memory advantage for humorous information over nonhumorous information. Two experiments investigated whether the positive effect of humor can occur with preventive health ads. In Experiment 1, participants observed humorous and nonhumorous health ads while their viewing times were recorded. In Experiment 2, to compare humorous and nonhumorous ads, the memory of health messages was assessed through a recognition task and a convincing score was collected. The results confirmed that, compared to nonhumorous health ads, those using humor received prolonged attention, were judged more convincing, and their messages were better recognized. Overall, these findings suggest that humor can be of use in preventive health communication.
Kao, Danny Tengti
2011-08-01
Persuasion has been extensively researched for decades. Much of this research has focused on different message tactics and their effects on persuasion (e.g., Chang & Chou, 2008; Lafferty, 1999). This research aims to assess whether the persuasion of a specific type of message is influenced by need for cognition (NFC) and time pressure. The 336 undergraduates participated in a 2 (message sidedness: one-sided/two-sided) × 3 (time pressure: low/moderate/high) between-subjects design. Results indicate that two-sided messages tend to elicit more favorable ad attitudes than one-sided messages. As compared with low-NFC individuals, high-NFC individuals are likely to express more favorable ad attitudes, brand attitudes and purchase intention. Moderate time pressure tends to lead to more favorable ad attitudes than low time pressure and high time pressure. In addition, moderate time pressure is likely to elicit more favorable brand attitudes and purchase intentions than high time pressure, but does not elicit more favorable brand attitudes and purchase intentions than low time pressure. Furthermore, when high-NFC individuals are under low or moderate time pressure, two-sided messages are more persuasive than one-sided messages; however, message sidedness does not differentially affect the persuasion when high-NFC individuals are pressed for time. In contrast, one-sided messages are more persuasive than two-sided messages when low-NFC individuals are under low or high time pressure, and two-sided messages are more persuasive than one-sided messages when low-NFC individuals are under moderate time pressure. © 2011 The Author. Scandinavian Journal of Psychology © 2011 The Scandinavian Psychological Associations.
Brannon, Timothy S
2006-01-01
Continuous infusion intravenous (IV) drugs in neonatal intensive care are usually prepared based on patient weight so that the dose is readable as a simple multiple of the infusion pump rate. New safety guidelines propose that hospitals switch to using standardized admixtures of these drugs to prevent calculation errors during ad hoc preparation. Extended hierarchical task analysis suggests that switching to standardized admixtures may lead to more errors in programming the pump at the bedside.
Brannon, Timothy S.
2006-01-01
Continuous infusion intravenous (IV) drugs in neonatal intensive care are usually prepared based on patient weight so that the dose is readable as a simple multiple of the infusion pump rate. New safety guidelines propose that hospitals switch to using standardized admixtures of these drugs to prevent calculation errors during ad hoc preparation. Extended hierarchical task analysis suggests that switching to standardized admixtures may lead to more errors in programming the pump at the bedside. PMID:17238482
2006-11-01
software components used in the ad hoc nodes for the C4ISR OTM experiment were OLSRD, an open-source proactive MANET routing software, and OpenVPN , an...developed by Mike Baker (openwrt.org). 6OpenVPN is a trademark of OpenVPN Solutions LLC. 6 Secure communications in the MANET are achieved with...encryption provided by Wired Equivalent Privacy (WEP) and OpenVPN . The WEP protocol, which is part of the IEEE 802.11 wireless networking standard
Power-Aware Intrusion Detection in Mobile Ad Hoc Networks
NASA Astrophysics Data System (ADS)
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.
Panel Discussion : Report of the APS Ad-Hoc Committee on LGBT Issues
NASA Astrophysics Data System (ADS)
Atherton, Tim; Barthelemy, Ramon; Garmon, Savannah; Reeves, Kyle; APS Ad-Hoc Committee on LGBT Issues Team
Following the presentation of the findings and recommendations of the APS Ad-Hoc Committee on LGBT Issues (C-LGBT) by Committee Chair Michael Falk, a panel discussion will be held featuring several members of the committee. The discussion will focus on how APS can best ensure the recommendations of the committee are carried out in a timely fashion and other ideas on future APS efforts toward LGBT inclusion in physics. Discussion topics will also include the research and other input that shaped the committee's findings and recommendations.
Mathematical representation of joint time-chroma distributions
NASA Astrophysics Data System (ADS)
Wakefield, Gregory H.
1999-11-01
Originally coined by the sensory psychologist Roger Shepard in the 1960s, chroma transforms frequency into octave equivalence classes. By extending the concept of chroma to chroma strength and how it varies over time, we have demonstrated the utility of chroma in simplifying the processing and representation of signals dominated by harmonically-related narrowband components. These investigations have utilized an ad hoc procedure for calculating the chromagram from a given time-frequency distribution. The present paper is intended to put this ad hoc procedure on more sound mathematical ground.
Healthy weight and lifestyle advertisements: an assessment of their persuasive potential.
Dixon, Helen; Scully, Maree; Cotter, Trish; Maloney, Sarah; Wakefield, Melanie
2015-08-01
This study aimed to identify and analyse the content of previously produced and aired adult-targeted public health advertisements (ads) addressing weight, nutrition or physical activity internationally. Ads were identified via keyword searches of Google, YouTube and websites of relevant government agencies and health organizations, and were eligible for inclusion if they were: in English; produced between 2007 and 2012; targeted at adults; ≤60 s; not promoting a particular commercial brand of food, fitness or weight loss product. Of the 99 ads coded, 59% featured supportive/encouraging messages, 36% presented information about health consequences and 17% focussed on social norms/acceptability issues. Supportive/encouraging messages were more frequently used in physical activity ads, while there were a higher proportion of messages about health consequences in weight ads. Execution style differed across lifestyle topics, with simulation/animation more common in nutrition ads and graphic images and negative personal testimonials in weight ads. Ads addressing weight were more likely to evoke high negative emotion and include potentially stigmatizing content. Understanding how weight and lifestyle issues have been addressed in recent public health advertising will help guide future efforts to test the effectiveness of different message types in facilitating positive behaviour changes. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.
ADS-B within a Multi-Aircraft Simulation for Distributed Air-Ground Traffic Management
NASA Technical Reports Server (NTRS)
Barhydt, Richard; Palmer, Michael T.; Chung, William W.; Loveness, Ghyrn W.
2004-01-01
Automatic Dependent Surveillance Broadcast (ADS-B) is an enabling technology for NASA s Distributed Air-Ground Traffic Management (DAG-TM) concept. DAG-TM has the goal of significantly increasing capacity within the National Airspace System, while maintaining or improving safety. Under DAG-TM, aircraft exchange state and intent information over ADS-B with other aircraft and ground stations. This information supports various surveillance functions including conflict detection and resolution, scheduling, and conformance monitoring. To conduct more rigorous concept feasibility studies, NASA Langley Research Center s PC-based Air Traffic Operations Simulation models a 1090 MHz ADS-B communication structure, based on industry standards for message content, range, and reception probability. The current ADS-B model reflects a mature operating environment and message interference effects are limited to Mode S transponder replies and ADS-B squitters. This model was recently evaluated in a Joint DAG-TM Air/Ground Coordination Experiment with NASA Ames Research Center. Message probability of reception vs. range was lower at higher traffic levels. The highest message collision probability occurred near the meter fix serving as the confluence for two arrival streams. Even the highest traffic level encountered in the experiment was significantly less than the industry standard "LA Basin 2020" scenario. Future studies will account for Mode A and C message interference (a major effect in several industry studies) and will include Mode A and C aircraft in the simulation, thereby increasing the total traffic level. These changes will support ongoing enhancements to separation assurance functions that focus on accommodating longer ADS-B information update intervals.
Baig, Sabeeh A; Byron, M Justin; Boynton, Marcella H; Brewer, Noel T; Ribisl, Kurt M
2017-04-01
Federal law now requires FDA to disseminate information on chemicals in cigarette smoke, but it is unclear how best to do so. In a 2 × 2 between-subjects experiment, participants received a message about chemicals in cigarette smoke (e.g., "Cigarette smoke has benzene.") along with an additional randomly assigned messaging strategy: a "found-in" (e.g., "This is found in gasoline."), a health effect (e.g., "This causes heart disease."), both, or neither. Participants were U.S. probability phone samples of 5000 adults and 1123 adolescents, and an online convenience sample of 4130 adults. Adding a health effect elicited greater discouragement from wanting to smoke cigarettes (all p < .05) as did adding a found-in (all p < .05). However, including both messaging strategies added little or nothing above including just one. These findings can help the FDA and other agencies develop effective and parsimonious messages about cigarette smoke constituents.
Harris, J L; Haraghey, K S; Lodolce, M; Semenza, N L
2018-04-01
Food companies often use healthy lifestyle messages in child-directed advertising, raising public health concerns about health halo effects for nutrient-poor food/drinks. Examine effects of health messages promoting nutrient-poor foods in child-directed advertising. Randomized controlled experiment (N = 138). Children (7-11 years) viewed three child-friendly commercials in one of three conditions: (1) health halo (unfamiliar nutrient-poor food/drink ads with healthy messages); (2) nutrient-poor food/drink ads with other messages and (3) healthy food/drink ads. They rated the commercials and advertised products, provided attitudes about exercise and nutrition and consumed and rated healthy and unhealthy snack foods. Children in the health halo condition rated the advertised nutrient-poor products as significantly healthier compared with children in other conditions (p = .003), but the other commercials did not affect children's attitudes about other advertised products (p's > .50). Child age, gender or TV viewing habits did not significantly predict their ratings (p's > .18). There was no evidence that healthy lifestyle messages and/or healthy food commercials improved children's attitudes about nutrition, exercise or healthy snack consumption. Promoting healthy lifestyle messages in child-directed commercials for nutrient-poor food/drinks likely benefits brands by increasing products' perceived healthfulness, but these ads are unlikely to positively affect children's attitudes about health and nutrition. © 2017 World Obesity Federation.
Dynamic autonomous routing technology for IP-based satellite ad hoc networks
NASA Astrophysics Data System (ADS)
Wang, Xiaofei; Deng, Jing; Kostas, Theresa; Rajappan, Gowri
2014-06-01
IP-based routing for military LEO/MEO satellite ad hoc networks is very challenging due to network and traffic heterogeneity, network topology and traffic dynamics. In this paper, we describe a traffic priority-aware routing scheme for such networks, namely Dynamic Autonomous Routing Technology (DART) for satellite ad hoc networks. DART has a cross-layer design, and conducts routing and resource reservation concurrently for optimal performance in the fluid but predictable satellite ad hoc networks. DART ensures end-to-end data delivery with QoS assurances by only choosing routing paths that have sufficient resources, supporting different packet priority levels. In order to do so, DART incorporates several resource management and innovative routing mechanisms, which dynamically adapt to best fit the prevailing conditions. In particular, DART integrates a resource reservation mechanism to reserve network bandwidth resources; a proactive routing mechanism to set up non-overlapping spanning trees to segregate high priority traffic flows from lower priority flows so that the high priority flows do not face contention from low priority flows; a reactive routing mechanism to arbitrate resources between various traffic priorities when needed; a predictive routing mechanism to set up routes for scheduled missions and for anticipated topology changes for QoS assurance. We present simulation results showing the performance of DART. We have conducted these simulations using the Iridium constellation and trajectories as well as realistic military communications scenarios. The simulation results demonstrate DART's ability to discriminate between high-priority and low-priority traffic flows and ensure disparate QoS requirements of these traffic flows.
An extended smart utilization medium access control (ESU-MAC) protocol for ad hoc wireless systems
NASA Astrophysics Data System (ADS)
Vashishtha, Jyoti; Sinha, Aakash
2006-05-01
The demand for spontaneous setup of a wireless communication system has increased in recent years for areas like battlefield, disaster relief operations etc., where a pre-deployment of network infrastructure is difficult or unavailable. A mobile ad-hoc network (MANET) is a promising solution, but poses a lot of challenges for all the design layers, specifically medium access control (MAC) layer. Recent existing works have used the concepts of multi-channel and power control in designing MAC layer protocols. SU-MAC developed by the same authors, efficiently uses the 'available' data and control bandwidth to send control information and results in increased throughput via decreasing contention on the control channel. However, SU-MAC protocol was limited for static ad-hoc network and also faced the busy-receiver node problem. We present the Extended SU-MAC (ESU-MAC) protocol which works mobile nodes. Also, we significantly improve the scheme of control information exchange in ESU-MAC to overcome the busy-receiver node problem and thus, further avoid the blockage of control channel for longer periods of time. A power control scheme is used as before to reduce interference and to effectively re-use the available bandwidth. Simulation results show that ESU-MAC protocol is promising for mobile, ad-hoc network in terms of reduced contention at the control channel and improved throughput because of channel re-use. Results show a considerable increase in throughput compared to SU-MAC which could be attributed to increased accessibility of control channel and improved utilization of data channels due to superior control information exchange scheme.
Greedy data transportation scheme with hard packet deadlines for wireless ad hoc networks.
Lee, HyungJune
2014-01-01
We present a greedy data transportation scheme with hard packet deadlines in ad hoc sensor networks of stationary nodes and multiple mobile nodes with scheduled trajectory path and arrival time. In the proposed routing strategy, each stationary ad hoc node en route decides whether to relay a shortest-path stationary node toward destination or a passing-by mobile node that will carry closer to destination. We aim to utilize mobile nodes to minimize the total routing cost as far as the selected route can satisfy the end-to-end packet deadline. We evaluate our proposed routing algorithm in terms of routing cost, packet delivery ratio, packet delivery time, and usability of mobile nodes based on network level simulations. Simulation results show that our proposed algorithm fully exploits the remaining time till packet deadline to turn into networking benefits of reducing the overall routing cost and improving packet delivery performance. Also, we demonstrate that the routing scheme guarantees packet delivery with hard deadlines, contributing to QoS improvement in various network services.
Greedy Data Transportation Scheme with Hard Packet Deadlines for Wireless Ad Hoc Networks
Lee, HyungJune
2014-01-01
We present a greedy data transportation scheme with hard packet deadlines in ad hoc sensor networks of stationary nodes and multiple mobile nodes with scheduled trajectory path and arrival time. In the proposed routing strategy, each stationary ad hoc node en route decides whether to relay a shortest-path stationary node toward destination or a passing-by mobile node that will carry closer to destination. We aim to utilize mobile nodes to minimize the total routing cost as far as the selected route can satisfy the end-to-end packet deadline. We evaluate our proposed routing algorithm in terms of routing cost, packet delivery ratio, packet delivery time, and usability of mobile nodes based on network level simulations. Simulation results show that our proposed algorithm fully exploits the remaining time till packet deadline to turn into networking benefits of reducing the overall routing cost and improving packet delivery performance. Also, we demonstrate that the routing scheme guarantees packet delivery with hard deadlines, contributing to QoS improvement in various network services. PMID:25258736
Taxonomic and ad hoc categorization within the two cerebral hemispheres.
Shen, Yeshayahu; Aharoni, Bat-El; Mashal, Nira
2015-01-01
A typicality effect refers to categorization which is performed more quickly or more accurately for typical than for atypical members of a given category. Previous studies reported a typicality effect for category members presented in the left visual field/right hemisphere (RH), suggesting that the RH applies a similarity-based categorization strategy. However, findings regarding the typicality effect within the left hemisphere (LH) are less conclusive. The current study tested the pattern of typicality effects within each hemisphere for both taxonomic and ad hoc categories, using words presented to the left or right visual fields. Experiment 1 tested typical and atypical members of taxonomic categories as well as non-members, and Experiment 2 tested typical and atypical members of ad hoc categories as well as non-members. The results revealed a typicality effect in both hemispheres and in both types of categories. Furthermore, the RH categorized atypical stimuli more accurately than did the LH. Our findings suggest that both hemispheres rely on a similarity-based categorization strategy, but the coarse semantic coding of the RH seems to facilitate the categorization of atypical members.
Proactive Alleviation Procedure to Handle Black Hole Attack and Its Version
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.
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.
Enhancement of Beaconless Location-Based Routing with Signal Strength Assistance for Ad-Hoc Networks
NASA Astrophysics Data System (ADS)
Chen, Guowei; Itoh, Kenichi; Sato, Takuro
Routing in Ad-hoc networks is unreliable due to the mobility of the nodes. Location-based routing protocols, unlike other protocols which rely on flooding, excel in network scalability. Furthermore, new location-based routing protocols, like, e. g. BLR [1], IGF [2], & CBF [3] have been proposed, with the feature of not requiring beacons in MAC-layer, which improve more in terms of scalability. Such beaconless routing protocols can work efficiently in dense network areas. However, these protocols' algorithms have no ability to avoid from routing into sparse areas. In this article, historical signal strength has been added as a factor into the BLR algorithm, which avoids routing into sparse area, and consequently improves the global routing efficiency.
ERIC Educational Resources Information Center
Congress of the U.S., Washington, DC. House Committee on Merchant Marine and Fisheries.
Recorded are minutes of hearings before the House Ad Hoc Select Subcommittee on Maritime Education and Training regarding the sea training of United States Merchant Marine officers. Examined are various approaches to meeting the sea training requirement, especially the options of maritime academy training vessels, sailing on U.S.-flag merchant…
Smart border: ad-hoc wireless sensor networks for border surveillance
NASA Astrophysics Data System (ADS)
He, Jun; Fallahi, Mahmoud; Norwood, Robert A.; Peyghambarian, Nasser
2011-06-01
Wireless sensor networks have been proposed as promising candidates to provide automated monitoring, target tracking, and intrusion detection for border surveillance. In this paper, we demonstrate an ad-hoc wireless sensor network system for border surveillance. The network consists of heterogeneously autonomous sensor nodes that distributively cooperate with each other to enable a smart border in remote areas. This paper also presents energy-aware and sleeping algorithms designed to maximize the operating lifetime of the deployed sensor network. Lessons learned in building the network and important findings from field experiments are shared in the paper.
Stochastic does not equal ad hoc. [theories of lunar origin
NASA Technical Reports Server (NTRS)
Hartmann, W. K.
1984-01-01
Some classes of influential events in solar system history are class-predictable but not event-predictable. Theories of lunar origin should not ignore class-predictable stochastic events. Impacts and close encounters with large objects during planet formation are class-predictable. These stochastic events, such as large impacts that triggered ejection of Earth-mantle material into a circum-Earth cloud, should not be rejected as ad hoc. A way to deal with such events scientifically is to investigate their consequences; if it can be shown that they might produce the Moon, they become viable concepts in theories of lunar origin.
Message sensation and cognition values: factors of competition or integration?
Xu, Jie
2015-01-01
Using the Activation Model of Information Exposure and Elaboration Likelihood Model as theoretical frameworks, this study explored the effects of message sensation value (MSV) and message cognition value (MCV) of antismoking public service announcements (PSAs) on ad processing and evaluation among young adults, and the difference between high sensation seekers and low sensation seekers in their perceptions and responses toward ads with different levels of sensation and cognition value. A 2 (MSV: high vs. low) × 2 (MCV: high vs. low) × 2 (need for sensation: high vs. low) mixed experimental design was conducted. Two physiological measures including skin conductance and heart rate were examined. Findings of this study show that MSV was not a distraction but a facilitator of message persuasiveness. These findings contribute to the activation model. In addition, need for sensation moderated the interaction effect of MSV and MCV on ad processing. Low sensation seekers were more likely to experience the interaction between MSV and MCV than high sensation seekers. Several observations related to the findings and implications for antismoking message designs are elaborated. Limitations and directions for future research are also outlined.
Engine monitoring display study
NASA Technical Reports Server (NTRS)
Hornsby, Mary E.
1992-01-01
The current study is part of a larger NASA effort to develop displays for an engine-monitoring system to enable the crew to monitor engine parameter trends more effectively. The objective was to evaluate the operational utility of adding three types of information to the basic Boeing Engine Indicating and Crew Alerting System (EICAS) display formats: alphanumeric alerting messages for engine parameters whose values exceed caution or warning limits; alphanumeric messages to monitor engine parameters that deviate from expected values; and a graphic depiction of the range of expected values for current conditions. Ten training and line pilots each flew 15 simulated flight scenarios with five variants of the basic EICAS format; these variants included different combinations of the added information. The pilots detected engine problems more quickly when engine alerting messages were included in the display; adding a graphic depiction of the range of expected values did not affect detection speed. The pilots rated both types of alphanumeric messages (alert and monitor parameter) as more useful and easier to interpret than the graphic depiction. Integrating engine parameter messages into the EICAS alerting system appears to be both useful and preferred.
Economic messages in prescription drug advertisements in medical journals.
Neumann, Peter J; Zivin Bambauer, Kara; Ramakrishnan, Vijay; Stewart, Kate A; Bell, Chaim M
2002-09-01
The extent to which pharmaceutical companies promote the economic advantages of their products in advertisements in medical journals, and whether such claims are supported by evidence, has not been quantified. Our objectives were to examine how often prescription drug advertisements in leading medical journals contain economic messages, and to determine the types of promotional claims made and whether supporting evidence is provided. All prescription drug advertisements appearing in six leading general medical and specialty journals in 3 selected months annually from 1990 to 1999 were reviewed. Using a standard data collection form, two reviewers examined each ad for economic content-including mention of the drug's price, value, cost saving, or cost-effectiveness. Economic messages appeared in 237 (11.1%) of the 2144 advertisements examined. Proportion of ads with economic content has increased over time (P = 0.003). Most frequently, economic ads contained statements that drugs were "less expensive" or "cost less" than alternative treatments (50.6% of economic ads). Supporting evidence for economic claims was clearly reported in 63.7% of cases, and typically referred to published drug prices rather than more detailed economic analysis. Ads for calcium channel blocking agents and ACE inhibitors frequently contained economic messages. Economic messages about prescription drugs are used in advertisements in leading medical journals and their frequency may be rising. Physicians should be aware of this phenomenon, and its potential impact on their prescribing decisions. More scrutiny of the supporting evidence underlying economic claims by the medical community and regulators may be needed.
a 3d Information System for the Documentation of Archaeologica L Excavations
NASA Astrophysics Data System (ADS)
Ardissone, P.; Bornaz, L.; Degattis, G.; Domaine, R.
2013-07-01
Documentation of archaeological and cultural heritage sites is at the heart of the archaeological process and an important component in cultural heritage research, presentation and restorations. In 2012 the Superintendence of Cultural Heritage of Aosta Valley - IT (Soprintendenza per i Beni e le Attività Culturali della Region e Autonoma Valle d'Aosta) carried out a complex archaeological excavation in a composite archaeological context, situated an urban background: the Aosta city centre. This archaeological excavation has been characterized by the classical urban archaeological issues: little space, short time, complex stratigraphy. Moreover the investigations have come out several structures and walls that required safety and conservation measures. Ad hoc 3D solutions carried out a complete 3D survey of the area in 10 different time/situations of the Archaeological digs, chosen in collaborations with the archaeological staff. In this way a multi temporal 3D description of the site has been provided for the archaeological analysis and for the project of the restorations activities. The 3D surveys has been carried out integrating GPS, laser scanner technology and photogrammetry. In order to meet the needs of the site, and its complex logistics and to obtain products that guarantee the high quality and detail required for archaeological analysis, we have developed different procedures and methodologies: hdr imaging for 3D model with correct, consistent and uniform colours, noise filtering and people filtering, for the removal of interference between laser instrument and object of the survey, Advanced laser scanner triangulation, in order to consider both artificial and natural tie points, for a correct registration of a huge amount of scans. Single image orientation on 3D data, in order to integrate the laser data with data coming from digital photogrammetry (faster on the field than the laser scanner survey, than used in certain situations). The results of all these methodologies and procedures will be presented and described in the article. For the documentation of the archaeological excavations and for the management of the conservation activities (condition assessment, planning, and conservation work). Ad Hoc 3D solutions has costumized 2 special plug-ins of its own software platform Ad Hoc: Ad Hoc Archaeology and Ad Hoc Conservation. The software platform integrates a 3D database management system. All information (measurements, plotting, areas of interests…) are organized according to their correct 3D position. They can be queried using attributes, geometric characteristics or their spatial position. The Ad Hoc Archaeology plug-in allows archeologists to fill out UUSS sheets in an internal database, put them in the correct location within the 3D model of the site, define the mutual relations between the UUSS, divide the different archaeological phases. A simple interface will facilitate the construction of the stratigraphic chart (matrix), in a 3D environment as well (matrix 3D). The Ad Hoc Conservation plug-in permits conservators and restorers to create relationships between the different approaches and descriptions of the same parts of the monument, i.e.: between stratigraphyc units or historical phases and architectural components and/or decay pathologies. The 3D DBMS conservation module uses a codified terminology based on "ICOMOS illustrated glossary of stone deterioration" and other glossary. Specific tools permits restorers to compute correctly surfaces and volumes. In this way decay extension and intensity can be measured with high precision and with an high level of detail, for a correct time and costs estimation of each conservation step.
Dynamic fair node spectrum allocation for ad hoc networks using random matrices
NASA Astrophysics Data System (ADS)
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.
Management of Energy Consumption on Cluster Based Routing Protocol for MANET
NASA Astrophysics Data System (ADS)
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.
T2AR: trust-aware ad-hoc routing protocol for MANET.
Dhananjayan, Gayathri; Subbiah, Janakiraman
2016-01-01
Secure data transfer against the malicious attacks is an important issue in an infrastructure-less independent network called mobile ad-hoc network (MANET). Trust assurance between MANET nodes is the key parameter in the high-security provision under dynamic topology variations and open wireless constraints. But, the malicious behavior of nodes reduces the trust level of the nodes that leads to an insecure data delivery. The increase in malicious attacks causes the excessive energy consumption that leads to a reduction of network lifetime. The lack of positional information update of the nodes in ad-hoc on-demand vector (AODV) protocol during the connection establishment offers less trust level between the nodes. Hence, the trust rate computation using energy and mobility models and its update are the essential tasks for secure data delivery. This paper proposes a trust-aware ad-hoc routing (T2AR) protocol to improve the trust level between the nodes in MANET. The proposed method modifies the traditional AODV routing protocol with the constraints of trust rate, energy, mobility based malicious behavior prediction. The packet sequence ID matching from the log reports of neighbor nodes determine the trust rate that avoids the malicious report generation. Besides, the direct and indirect trust observation schemes utilization increases the trust level. Besides, the received signal strength indicator utilization determines the trusted node is within the communication range or not. The comparative analysis between the proposed T2AR with the existing methods such as TRUNCMAN, RBT, GR, FBR and DICOTIDS regarding the average end-to-end delay, throughput, false positives, packet delivery ratio shows the effectiveness of T2AR in the secure MANET environment design.
Technologies for network-centric C4ISR
NASA Astrophysics Data System (ADS)
Dunkelberger, Kirk A.
2003-07-01
Three technologies form the heart of any network-centric command, control, communication, intelligence, surveillance, and reconnaissance (C4ISR) system: distributed processing, reconfigurable networking, and distributed resource management. Distributed processing, enabled by automated federation, mobile code, intelligent process allocation, dynamic multiprocessing groups, check pointing, and other capabilities creates a virtual peer-to-peer computing network across the force. Reconfigurable networking, consisting of content-based information exchange, dynamic ad-hoc routing, information operations (perception management) and other component technologies forms the interconnect fabric for fault tolerant inter processor and node communication. Distributed resource management, which provides the means for distributed cooperative sensor management, foe sensor utilization, opportunistic collection, symbiotic inductive/deductive reasoning and other applications provides the canonical algorithms for network-centric enterprises and warfare. This paper introduces these three core technologies and briefly discusses a sampling of their component technologies and their individual contributions to network-centric enterprises and warfare. Based on the implied requirements, two new algorithms are defined and characterized which provide critical building blocks for network centricity: distributed asynchronous auctioning and predictive dynamic source routing. The first provides a reliable, efficient, effective approach for near-optimal assignment problems; the algorithm has been demonstrated to be a viable implementation for ad-hoc command and control, object/sensor pairing, and weapon/target assignment. The second is founded on traditional dynamic source routing (from mobile ad-hoc networking), but leverages the results of ad-hoc command and control (from the contributed auctioning algorithm) into significant increases in connection reliability through forward prediction. Emphasis is placed on the advantages gained from the closed-loop interaction of the multiple technologies in the network-centric application environment.
Mashup Model and Verification Using Mashup Processing Network
NASA Astrophysics Data System (ADS)
Zahoor, Ehtesham; Perrin, Olivier; Godart, Claude
Mashups are defined to be lightweight Web applications aggregating data from different Web services, built using ad-hoc composition and being not concerned with long term stability and robustness. In this paper we present a pattern based approach, called Mashup Processing Network (MPN). The idea is based on Event Processing Network and is supposed to facilitate the creation, modeling and the verification of mashups. MPN provides a view of how different actors interact for the mashup development namely the producer, consumer, mashup processing agent and the communication channels. It also supports modeling transformations and validations of data and offers validation of both functional and non-functional requirements, such as reliable messaging and security, that are key issues within the enterprise context. We have enriched the model with a set of processing operations and categorize them into data composition, transformation and validation categories. These processing operations can be seen as a set of patterns for facilitating the mashup development process. MPN also paves a way for realizing Mashup Oriented Architecture where mashups along with services are used as building blocks for application development.
Mobility based key management technique for multicast security in mobile ad hoc networks.
Madhusudhanan, B; Chitra, S; Rajan, C
2015-01-01
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.
Fotopoulos, Christos; Krystallis, Athanasios; Vassallo, Marco; Pagiaslis, Anastasios
2009-02-01
Recognising the need for a more statistically robust instrument to investigate general food selection determinants, the research validates and confirms Food Choice Questionnaire (FCQ's) factorial design, develops ad hoc a more robust FCQ version and tests its ability to discriminate between consumer segments in terms of the importance they assign to the FCQ motivational factors. The original FCQ appears to represent a comprehensive and reliable research instrument. However, the empirical data do not support the robustness of its 9-factorial design. On the other hand, segmentation results at the subpopulation level based on the enhanced FCQ version bring about an optimistic message for the FCQ's ability to predict food selection behaviour. The paper concludes that some of the basic components of the original FCQ can be used as a basis for a new general food motivation typology. The development of such a new instrument, with fewer, of higher abstraction FCQ-based dimensions and fewer items per dimension, is a right step forward; yet such a step should be theory-driven, while a rigorous statistical testing across and within population would be necessary.
Sensor Data Distribution With Robustness and Reliability: Toward Distributed Components Model
NASA Technical Reports Server (NTRS)
Alena, Richard L.; Lee, Charles
2005-01-01
In planetary surface exploration mission, sensor data distribution is required in many aspects, for example, in navigation, scheduling, planning, monitoring, diagnostics, and automation of the field tasks. The challenge is to distribute such data in the robust and reliable way so that we can minimize the errors caused by miscalculations, and misjudgments that based on the error data input in the mission. The ad-hoc wireless network on planetary surface is not constantly connected because of the nature of the rough terrain and lack of permanent establishments on the surface. There are some disconnected moments that the computation nodes will re-associate with different repeaters or access points until connections are reestablished. Such a nature requires our sensor data distribution software robust and reliable with ability to tolerant disconnected moments. This paper presents a distributed components model as a framework to accomplish such tasks. The software is written in Java and utilized the available Java Message Services schema and the Boss implementation. The results of field experimentations show that the model is very effective in completing the tasks.
NASA Langley Atmospheric Science Data Center (ASDC) Experience with Aircraft Data
NASA Astrophysics Data System (ADS)
Perez, J.; Sorlie, S.; Parker, L.; Mason, K. L.; Rinsland, P.; Kusterer, J.
2011-12-01
Over the past decade the NASA Langley ASDC has archived and distributed a variety of aircraft mission data sets. These datasets posed unique challenges for archiving from the rigidity of the archiving system and formats to the lack of metadata. The ASDC developed a state-of-the-art data archive and distribution system to serve the atmospheric sciences data provider and researcher communities. The system, called Archive - Next Generation (ANGe), is designed with a distributed, multi-tier, serviced-based, message oriented architecture enabling new methods for searching, accessing, and customizing data. The ANGe system provides the ease and flexibility to ingest and archive aircraft data through an ad hoc workflow or to develop a new workflow to suit the providers needs. The ASDC will describe the challenges encountered in preparing aircraft data for archiving and distribution. The ASDC is currently providing guidance to the DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) Earth Venture-1 project on developing collection, granule, and browse metadata as well as supporting the ADAM (Airborne Data For Assessing Models) site.
Use of the PHM Framework to Create Safe-Sex Ads Targeted to Mature Women 50 and Older.
Morton, Cynthia R; Kim, Hyojin
2015-01-01
This research applies the Witte's persuasive health message (PHM) framework to the development of creative concepts that promote sexual health strategies to senior-aged women. The PHM framework proposes an integrated approach to improving message effectiveness and maximizing persuasion in health communication campaigns. A focus group method was used to explore two research questions focused on message effectiveness and persuasion. The findings suggest the PHM framework can be a useful starting point for ensuring that health communicators identify the criteria most relevant to successful ad promotions.
Parent ads in the National Youth Anti-Drug Media Campaign.
Stephenson, Michael T; Quick, Brian L
2005-12-01
The National Youth Anti-Drug Media Campaign aims not only to reduce drug use by teens and preteens, but also to arm parents with knowledge about specific parenting practices known to reduce the risk of teen drug use. Among the documented successes of the campaign to date was a small, but direct effect on some parenting practices, including parent-child discussions about drug use. To reach a deeper understanding about the substance of the parental ads, we content analyzed the message strategies employed in the campaign's parent ads over the inaugural 5 years of the campaign. Each ad was coded for its major theme, minor subtheme, and featured drug. Among seven possible major themes, the parental anti-drug ads largely featured four: enhance the risk of their child's drug use, encourage monitoring practices, promote parent-child discussions about drug use, or advocate positive involvement behaviors. Moreover, most parental messages addressed marijuana use or addressed drug use in general. Marijuana and inhalant ads largely were risk based, while general drug messages focused on monitoring, parent-child discussions or positive involvement practices.
Kokkinos, P; Kozyra, I; Lazic, S; Bouwknegt, M; Rutjes, S; Willems, K; Moloney, R; de Roda Husman, A M; Kaupke, A; Legaki, E; D'Agostino, M; Cook, N; Rzeżutka, A; Petrovic, T; Vantarakis, A
2012-12-01
Numerous outbreaks have been attributed to the consumption of raw or minimally processed leafy green vegetables contaminated with enteric viral pathogens. The aim of the present study was an integrated virological monitoring of the salad vegetables supply chain in Europe, from production, processing and point-of-sale. Samples were collected and analysed in Greece, Serbia and Poland, from 'general' and 'ad hoc' sampling points, which were perceived as critical points for virus contamination. General sampling points were identified through the analysis of background information questionnaires based on HACCP audit principles, and they were sampled during each sampling occasion where as-ad hoc sampling points were identified during food safety fact-finding visits and samples were only collected during the fact-finding visits. Human (hAdV) and porcine (pAdV) adenovirus, hepatitis A (HAV) and E (HEV) virus, norovirus GI and GII (NoV) and bovine polyomavirus (bPyV) were detected by means of real-time (RT-) PCR-based protocols. General samples were positive for hAdV, pAdV, HAV, HEV, NoV GI, NoV GII and bPyV at 20.09 % (134/667), 5.53 % (13/235), 1.32 % (4/304), 3.42 % (5/146), 2 % (6/299), 2.95 % (8/271) and 0.82 % (2/245), respectively. Ad hoc samples were positive for hAdV, pAdV, bPyV and NoV GI at 9 % (3/33), 9 % (2/22), 4.54 % (1/22) and 7.14 % (1/14), respectively. These results demonstrate the existence of viral contamination routes from human and animal sources to the salad vegetable supply chain and more specifically indicate the potential for public health risks due to the virus contamination of leafy green vegetables at primary production.
Creating Effective Media Messaging for Rural Smoke-free Policy.
Riker, Carol A; Butler, Karen M; Ricks, JaNelle M; Record, Rachael A; Begley, Kathy; Anderson, Debra Gay; Hahn, Ellen J
2015-01-01
Objectives were to (1) explore perceived effectiveness of existing smoke-free print advertisements in rural communities and (2) generate message content, characteristics, and media delivery channels that resonate with residents. Qualitative methods design. Thirty-nine rural adults recruited by community partners. Content analysis of findings from individuals in four focus groups who participated in general discussion and reviewed eight print ads related to secondhand smoke (SHS) and smoke-free policy. Six content themes were identified: smoking/SHS dangers, worker health, analogies, economic impact, rights, and nostalgia. Seven message characteristics were recognized: short/to the point, large enough to read, graphic images, poignant stories, statistics/charts/graphs, message sender, and messages targeting different groups. Four media delivery channels were considered most effective: local media, technology, billboard messages, and print materials. Seeking input from key informants is essential to reaching rural residents. Use of analogies in media messaging is a distinct contribution to the literature on effective smoke-free campaigns. Other findings support previous studies of effective messaging and delivery channels. Further research is needed to examine effectiveness of themes related to message content in smoke-free ads and delivery strategies. Effective media messaging can lead to policy change in rural communities to reduce exposure to SHS. © 2015 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Agueh, Max; Diouris, Jean-François; Diop, Magaye; Devaux, François-Olivier; De Vleeschouwer, Christophe; Macq, Benoit
2008-12-01
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.
Scalable Architecture for Multihop Wireless ad Hoc Networks
NASA Technical Reports Server (NTRS)
Arabshahi, Payman; Gray, Andrew; Okino, Clayton; Yan, Tsun-Yee
2004-01-01
A scalable architecture for wireless digital data and voice communications via ad hoc networks has been proposed. Although the details of the architecture and of its implementation in hardware and software have yet to be developed, the broad outlines of the architecture are fairly clear: This architecture departs from current commercial wireless communication architectures, which are characterized by low effective bandwidth per user and are not well suited to low-cost, rapid scaling in large metropolitan areas. This architecture is inspired by a vision more akin to that of more than two dozen noncommercial community wireless networking organizations established by volunteers in North America and several European countries.
Intelligent QoS routing algorithm based on improved AODV protocol for Ad Hoc networks
NASA Astrophysics Data System (ADS)
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.
A secure 3-way routing protocols for intermittently connected mobile ad hoc networks.
Sekaran, Ramesh; Parasuraman, Ganesh Kumar
2014-01-01
The mobile ad hoc network may be partially connected or it may be disconnected in nature and these forms of networks are termed intermittently connected mobile ad hoc network (ICMANET). The routing in such disconnected network is commonly an arduous task. Many routing protocols have been proposed for routing in ICMANET since decades. The routing techniques in existence for ICMANET are, namely, flooding, epidemic, probabilistic, copy case, spray and wait, and so forth. These techniques achieve an effective routing with minimum latency, higher delivery ratio, lesser overhead, and so forth. Though these techniques generate effective results, in this paper, we propose novel routing algorithms grounded on agent and cryptographic techniques, namely, location dissemination service (LoDiS) routing with agent AES, A-LoDiS with agent AES routing, and B-LoDiS with agent AES routing, ensuring optimal results with respect to various network routing parameters. The algorithm along with efficient routing ensures higher degree of security. The security level is cited testing with respect to possibility of malicious nodes into the network. This paper also aids, with the comparative results of proposed algorithms, for secure routing in ICMANET.
A Secure 3-Way Routing Protocols for Intermittently Connected Mobile Ad Hoc Networks
Parasuraman, Ganesh Kumar
2014-01-01
The mobile ad hoc network may be partially connected or it may be disconnected in nature and these forms of networks are termed intermittently connected mobile ad hoc network (ICMANET). The routing in such disconnected network is commonly an arduous task. Many routing protocols have been proposed for routing in ICMANET since decades. The routing techniques in existence for ICMANET are, namely, flooding, epidemic, probabilistic, copy case, spray and wait, and so forth. These techniques achieve an effective routing with minimum latency, higher delivery ratio, lesser overhead, and so forth. Though these techniques generate effective results, in this paper, we propose novel routing algorithms grounded on agent and cryptographic techniques, namely, location dissemination service (LoDiS) routing with agent AES, A-LoDiS with agent AES routing, and B-LoDiS with agent AES routing, ensuring optimal results with respect to various network routing parameters. The algorithm along with efficient routing ensures higher degree of security. The security level is cited testing with respect to possibility of malicious nodes into the network. This paper also aids, with the comparative results of proposed algorithms, for secure routing in ICMANET. PMID:25136697
Energy Efficient Probabilistic Broadcasting for Mobile Ad-Hoc Network
NASA Astrophysics Data System (ADS)
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).
DataSpread: Unifying Databases and Spreadsheets.
Bendre, Mangesh; Sun, Bofan; Zhang, Ding; Zhou, Xinyan; Chang, Kevin ChenChuan; Parameswaran, Aditya
2015-08-01
Spreadsheet software is often the tool of choice for ad-hoc tabular data management, processing, and visualization, especially on tiny data sets. On the other hand, relational database systems offer significant power, expressivity, and efficiency over spreadsheet software for data management, while lacking in the ease of use and ad-hoc analysis capabilities. We demonstrate DataSpread, a data exploration tool that holistically unifies databases and spreadsheets. It continues to offer a Microsoft Excel-based spreadsheet front-end, while in parallel managing all the data in a back-end database, specifically, PostgreSQL. DataSpread retains all the advantages of spreadsheets, including ease of use, ad-hoc analysis and visualization capabilities, and a schema-free nature, while also adding the advantages of traditional relational databases, such as scalability and the ability to use arbitrary SQL to import, filter, or join external or internal tables and have the results appear in the spreadsheet. DataSpread needs to reason about and reconcile differences in the notions of schema, addressing of cells and tuples, and the current "pane" (which exists in spreadsheets but not in traditional databases), and support data modifications at both the front-end and the back-end. Our demonstration will center on our first and early prototype of the DataSpread, and will give the attendees a sense for the enormous data exploration capabilities offered by unifying spreadsheets and databases.
DataSpread: Unifying Databases and Spreadsheets
Bendre, Mangesh; Sun, Bofan; Zhang, Ding; Zhou, Xinyan; Chang, Kevin ChenChuan; Parameswaran, Aditya
2015-01-01
Spreadsheet software is often the tool of choice for ad-hoc tabular data management, processing, and visualization, especially on tiny data sets. On the other hand, relational database systems offer significant power, expressivity, and efficiency over spreadsheet software for data management, while lacking in the ease of use and ad-hoc analysis capabilities. We demonstrate DataSpread, a data exploration tool that holistically unifies databases and spreadsheets. It continues to offer a Microsoft Excel-based spreadsheet front-end, while in parallel managing all the data in a back-end database, specifically, PostgreSQL. DataSpread retains all the advantages of spreadsheets, including ease of use, ad-hoc analysis and visualization capabilities, and a schema-free nature, while also adding the advantages of traditional relational databases, such as scalability and the ability to use arbitrary SQL to import, filter, or join external or internal tables and have the results appear in the spreadsheet. DataSpread needs to reason about and reconcile differences in the notions of schema, addressing of cells and tuples, and the current “pane” (which exists in spreadsheets but not in traditional databases), and support data modifications at both the front-end and the back-end. Our demonstration will center on our first and early prototype of the DataSpread, and will give the attendees a sense for the enormous data exploration capabilities offered by unifying spreadsheets and databases. PMID:26900487
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tang, J. Y.; Riley, W. J.
We present a generic flux limiter to account for mass limitations from an arbitrary number of substrates in a biogeochemical reaction network. The flux limiter is based on the observation that substrate (e.g., nitrogen, phosphorus) limitation in biogeochemical models can be represented as to ensure mass conservative and non-negative numerical solutions to the governing ordinary differential equations. Application of the flux limiter includes two steps: (1) formulation of the biogeochemical processes with a matrix of stoichiometric coefficients and (2) application of Liebig's law of the minimum using the dynamic stoichiometric relationship of the reactants. This approach contrasts with the ad hoc down-regulationmore » approaches that are implemented in many existing models (such as CLM4.5 and the ACME (Accelerated Climate Modeling for Energy) Land Model (ALM)) of carbon and nutrient interactions, which are error prone when adding new processes, even for experienced modelers. Through an example implementation with a CENTURY-like decomposition model that includes carbon, nitrogen, and phosphorus, we show that our approach (1) produced almost identical results to that from the ad hoc down-regulation approaches under non-limiting nutrient conditions, (2) properly resolved the negative solutions under substrate-limited conditions where the simple clipping approach failed, (3) successfully avoided the potential conceptual ambiguities that are implied by those ad hoc down-regulation approaches. We expect our approach will make future biogeochemical models easier to improve and more robust.« less
Helping me, helping you: self-referencing and gender roles in donor advertising.
Hupfer, M E
2006-06-01
Donor advertising typically emphasizes altruism, but an appeal to individual self-interest may be more effective in heightening blood donation intentions among youthful nondonors. A total of 292 undergraduate business students at a Canadian university provided complete data in response to a between-subjects full-factorial advertising experiment with sex, self-referencing, and message strategy factors. Self-referencing, or mental processing that links information to the self-concept, was elicited at either a low or moderate level, whereas the message strategy was either agentic (donate blood because you may need it yourself) or communal (donate blood because someone close to you may need it). Dependent variables included identification with the ad, donation intentions, and a discrimination measure of recognition memory. A three-way interaction among sex, self-referencing level (low or moderate), and message (agentic or communal) was found. Two-way self-referencing by message graphs of donation intentions and ad identification showed a parallel structure for males in that their responses were generally more favorable when self-referencing was at a moderate level, regardless of the message type. Among women, however, crossover interactions between the level of self-referencing and the message type (agentic vs. communal) were observed, such that the message's effect differed with the level of self-referencing. For both men and women, the agentic message was more effective than communal ad copy when a moderate level of self-referencing was achieved. Collection agencies should consider appealing to young nondonors by suggesting that they give blood to make it available for themselves if required.
Testing messages to reduce smokers’ openness to using novel smokeless tobacco products
Popova, Lucy; Neilands, Torsten B.; Ling, Pamela M.
2013-01-01
Introduction Tobacco manufacturers’ aggressive promotion of new smokeless tobacco products such as snus warrants a timely and effective public health response. This study tested potential counter-marketing messages to discourage current and former smokers from becoming dual users of smokeless tobacco and cigarettes. Methods In a pretest – post-test experiment, 1,836 adult current and recently former smokers from a national sample were randomized to view one of six anti-smokeless tobacco ads followed by a snus ad, to view a control ad followed by a snus ad; or to view two control ads. Perceived effectiveness of ads and actual changes in attitudes and openness to snus were compared across groups using analyses of variance. Results Some ads that were perceived as most effective did not change attitudes or openness to trying snus, and conversely, some ads not perceived as effective changed attitudes and openness to snus. Ads portraying the negative health effects of smokeless tobacco were perceived as most effective, but ads with anti-tobacco industry themes significantly decreased favorable attitudes toward snus. Responses to ads were different for smokers who had ever used smokeless tobacco: for this group health effects and humorous/testimonial ads were effective. Conclusions Measures of perceived effectiveness of anti-tobacco ads need to be augmented with measures of actual effectiveness to assess counter-marketing messages. Some of the developed ads, such as ads with anti-industry themes, were effective for the overall population of smokers whereas humorous/testimonial and health effects ads were particularly effective in changing attitudes of past users of smokeless tobacco. PMID:23467655
2011-01-01
Background How youth perceive marketing messages in sports is poorly understood. We evaluated whether youth perceive that the imagery of a specific sports marketing advertisement contained smoking-related messages. Methods Twenty grade 7 to 11 classes (397 students) from two high schools in Montréal, Canada were recruited to participate in a cluster randomised single-blind controlled trial. Classes were randomly allocated to either a NIKE advertisement containing the phrase 'LIGHT IT UP' (n = 205) or to a neutral advertisement with smoking imagery reduced and the phrase replaced by 'GO FOR IT' (n = 192). The NIKE logo was removed from both advertisements. Students responded in class to a questionnaire asking open-ended questions about their perception of the messages in the ad. Reports relating to the appearance and text of the ad, and the product being promoted were evaluated. Results Relative to the neutral ad, more students reported that the phrase 'LIGHT IT UP' was smoking-related (37.6% vs. 0.5%) and that other parts of the ad resembled smoking-related products (50.7% vs. 10.4%). The relative risk of students reporting that the NIKE ad promoted cigarettes was 4.41 (95% confidence interval: 2.64-7.36; P < 0.001). Conclusions The unbranded imagery of an advertisement in a specific campaign aimed at promoting NIKE hockey products appears to have contained smoking-related messages. This particular marketing campaign may have promoted smoking. This suggests that the regulation of marketing to youth may need to be more tightly controlled. PMID:21477307
Auger, Nathalie; Daniel, Mark; Knäuper, Bärbel; Raynault, Marie-France; Pless, Barry
2011-04-08
How youth perceive marketing messages in sports is poorly understood. We evaluated whether youth perceive that the imagery of a specific sports marketing advertisement contained smoking-related messages. Twenty grade 7 to 11 classes (397 students) from two high schools in Montréal, Canada were recruited to participate in a cluster randomised single-blind controlled trial. Classes were randomly allocated to either a NIKE advertisement containing the phrase 'LIGHT IT UP' (n = 205) or to a neutral advertisement with smoking imagery reduced and the phrase replaced by 'GO FOR IT' (n = 192). The NIKE logo was removed from both advertisements. Students responded in class to a questionnaire asking open-ended questions about their perception of the messages in the ad. Reports relating to the appearance and text of the ad, and the product being promoted were evaluated. Relative to the neutral ad, more students reported that the phrase 'LIGHT IT UP' was smoking-related (37.6% vs. 0.5%) and that other parts of the ad resembled smoking-related products (50.7% vs. 10.4%). The relative risk of students reporting that the NIKE ad promoted cigarettes was 4.41 (95% confidence interval: 2.64-7.36; P < 0.001). The unbranded imagery of an advertisement in a specific campaign aimed at promoting NIKE hockey products appears to have contained smoking-related messages. This particular marketing campaign may have promoted smoking. This suggests that the regulation of marketing to youth may need to be more tightly controlled.
Ju, Ilwoo; Park, Jin Seong
2015-01-01
This study addresses a void in the literature on direct-to-consumer prescription drug advertising (DTCA) with a theory-based content analysis. The findings indicate that Taylor's communication strategy wheel provides insight into what and how pharmaceutical marketers communicate with consumers by means of DTCA. Major findings are summarized as follows: (a) In most DTC ads, informational and transformational message themes and creative approaches were simultaneously used, indicating a combination strategy; (b) DTCA message themes were associated with creative strategies in alignment with Taylor's framework; and (c) message themes and creative strategies varied across therapeutic categories and DTCA categories with different levels of ad spending. Theoretical and practical implications of the findings are discussed.
Lin, Chia-Yen; Yeh, Wei-Ju
2017-12-04
The health costs of colorectal cancer have increased over the years in Taiwan. The National Health Insurance Administration (NHI) and the Health Promotion Administration of the Ministry of Health and Welfare (MOHW) in Taiwan advocate that people have to change their unhealthy behaviors; however, the number of patients of colorectal cancer is increasing annually. This research discussed the effects of healthy diet advocacy advertisements (ads) on healthy diet behavior intentions as influenced by the interactions between regulatory focus theory (RFT) and message framing effects. Both regulatory focus theory and message framing effect were discussed for the relationship between advertisement and behavior change in many fields, such as health-related behavior, pro-environmental behavior, consumer choice, etc. We executed an experiment with four different types of public health advocacy ads. A 2 (regulatory focus: promotion vs. prevention) × 2 (message framing: gain framing vs. loss framing) two-factor experiment was adopted, and 201 valid participants responded to the questionnaire. Results indicated that if the ad's regulatory focus is promotion focus, viewers' attitudes toward the ad and their behavior intentions are more positive when the slogan of the ad is gain framing rather than loss framing via the multiple analysis of variance (MANOVA), and vice versa. Respondents found the communication easier to comprehend when the ads evoked the respondents' regulatory focus and applied the appropriate message framing, thus improving the efficacy of health-related advertising. We offer suggestions regarding the future use of health-related advertising for the MOHW.
Effects of E-cigarette Advertising Messages and Cues on Cessation Outcomes.
Jo, Catherine L; Golden, Shelley D; Noar, Seth M; Rini, Christine; Ribisl, Kurt M
2018-01-01
We examined effects of e-cigarette ad messages and visual cues on outcomes related to combustible cigarette smoking cessation: smoking cessation intention, smoking urges, and immediate smoking behavior. US adult smokers (N = 3293) were recruited through Amazon Mechanical Turk and randomized to condition in a 3 (message: e-cigarette use anywhere, harm reduction, control) × 2 (e-cigarette cue presence or absence) between-subjects experiment. Stimuli were print ads for cigarette-like e-cigarettes ("cigalikes") that were manipulated for the experimental conditions. We conducted ANOVA and logistic regression analyses to investigate effects of the manipulations. Message effects on cessation intention and smoking urges were not statistically significant. There was no evidence of cue effects or message × cue interactions across outcomes. Contrary to expectations, e-cigarette use anywhere and harm reduction messages were associated with lower odds of immediate smoking than the control message (AOR EUA = 0.75, 95%CI = 0.58, 0.97, p = .026; AOR HR = 0.72, 95%CI = 0.55, 0.93, p = .013). E-cigarette use anywhere and harm reduction messages may encourage smoking cessation, given the observed reduction in immediate smoking. E-cigarette cues may not influence smoking cessation outcomes. Future studies should investigate whether message effects are a result of smokers believing e-cigarettes to be effective cessation aids.
Maintaining Limited-Range Connectivity Among Second-Order Agents
2016-07-07
we consider ad-hoc networks of robotic agents with double integrator dynamics. For such networks, the connectivity maintenance problems are: (i) do...hoc networks of mobile autonomous agents. This loose ter- minology refers to groups of robotic agents with limited mobility and communica- tion...connectivity can be preserved. 3.1. Networks of robotic agents with second-order dynamics and the connectivity maintenance problem. We begin by
Where Do Community Colleges Stand?
ERIC Educational Resources Information Center
Pietak, Raymond
1971-01-01
Traditional clubs and structures continue to serve needs of interested students. However, more socially aware students must have operational vehicles to meet their dynamic needs. The identification of problem areas and the creation of ad hoc interest groups should be added to the college activity programs. (Author)
Mixed messages: residents' experiences learning cross-cultural care.
Park, Elyse R; Betancourt, Joseph R; Kim, Minah K; Maina, Angela W; Blumenthal, David; Weissman, Joel S
2005-09-01
An Institute of Medicine report issued in 2002 cited cross-cultural training as a mechanism to address racial and ethnic disparities in health care, but little is known about residents' training and capabilities to provide quality care to diverse populations. This article explores a select group of residents' perceptions of their preparedness to deliver quality care to diverse populations. Seven focus groups and ten individual interviews were conducted with 68 residents in locations nationwide. Qualitative analysis of focus-group and individual interview transcripts was performed to assess residents' perceptions of (1) preparedness to deliver care to diverse patients; (2) educational climate; and (3) training experiences. Most residents in this study noted the importance of cross-cultural care yet reported little formal training in this area. Residents wanted more formal training yet expressed concern that culture-specific training could lead to stereotyping. Most residents had developed ad hoc, informal skills to care for diverse patients. Although residents perceived institutional endorsement, they sensed it was a low priority due to lack of time and resources. Residents in this study reported receiving mixed messages about cross-cultural care. They were told it is important, yet they received little formal training and did not have time to treat diverse patients in a culturally sensitive manner. As a result, many developed coping behaviors rather than skills based on formally taught best practices. Training environments need to increase training to enhance residents' preparedness to deliver high-quality cross-cultural care if the medical profession is to achieve the goals set by the Institute of Medicine.
A memetic optimization algorithm for multi-constrained multicast routing in ad hoc networks
Hammad, Karim; El Bakly, Ahmed M.
2018-01-01
A mobile ad hoc network is a conventional self-configuring network where the routing optimization problem—subject to various Quality-of-Service (QoS) constraints—represents a major challenge. Unlike previously proposed solutions, in this paper, we propose a memetic algorithm (MA) employing an adaptive mutation parameter, to solve the multicast routing problem with higher search ability and computational efficiency. The proposed algorithm utilizes an updated scheme, based on statistical analysis, to estimate the best values for all MA parameters and enhance MA performance. The numerical results show that the proposed MA improved the delay and jitter of the network, while reducing computational complexity as compared to existing algorithms. PMID:29509760
A memetic optimization algorithm for multi-constrained multicast routing in ad hoc networks.
Ramadan, Rahab M; Gasser, Safa M; El-Mahallawy, Mohamed S; Hammad, Karim; El Bakly, Ahmed M
2018-01-01
A mobile ad hoc network is a conventional self-configuring network where the routing optimization problem-subject to various Quality-of-Service (QoS) constraints-represents a major challenge. Unlike previously proposed solutions, in this paper, we propose a memetic algorithm (MA) employing an adaptive mutation parameter, to solve the multicast routing problem with higher search ability and computational efficiency. The proposed algorithm utilizes an updated scheme, based on statistical analysis, to estimate the best values for all MA parameters and enhance MA performance. The numerical results show that the proposed MA improved the delay and jitter of the network, while reducing computational complexity as compared to existing algorithms.
Evolution of Geometric Sensitivity Derivatives from Computer Aided Design Models
NASA Technical Reports Server (NTRS)
Jones, William T.; Lazzara, David; Haimes, Robert
2010-01-01
The generation of design parameter sensitivity derivatives is required for gradient-based optimization. Such sensitivity derivatives are elusive at best when working with geometry defined within the solid modeling context of Computer-Aided Design (CAD) systems. Solid modeling CAD systems are often proprietary and always complex, thereby necessitating ad hoc procedures to infer parameter sensitivity. A new perspective is presented that makes direct use of the hierarchical associativity of CAD features to trace their evolution and thereby track design parameter sensitivity. In contrast to ad hoc methods, this method provides a more concise procedure following the model design intent and determining the sensitivity of CAD geometry directly to its respective defining parameters.
Ad Hoc Selection of Voice over Internet Streams
NASA Technical Reports Server (NTRS)
Macha, Mitchell G. (Inventor); Bullock, John T. (Inventor)
2014-01-01
A method and apparatus for a communication system technique involving ad hoc selection of at least two audio streams is provided. Each of the at least two audio streams is a packetized version of an audio source. A data connection exists between a server and a client where a transport protocol actively propagates the at least two audio streams from the server to the client. Furthermore, software instructions executable on the client indicate a presence of the at least two audio streams, allow selection of at least one of the at least two audio streams, and direct the selected at least one of the at least two audio streams for audio playback.
Ad Hoc Selection of Voice over Internet Streams
NASA Technical Reports Server (NTRS)
Macha, Mitchell G. (Inventor); Bullock, John T. (Inventor)
2008-01-01
A method and apparatus for a communication system technique involving ad hoc selection of at least two audio streams is provided. Each of the at least two audio streams is a packetized version of an audio source. A data connection exists between a server and a client where a transport protocol actively propagates the at least two audio streams from the server to the client. Furthermore, software instructions executable on the client indicate a presence of the at least two audio streams, allow selection of at least one of the at least two audio streams, and direct the selected at least one of the at least two audio streams for audio playback.
Scalable Authenticated Tree Based Group Key Exchange for Ad-Hoc Groups
NASA Astrophysics Data System (ADS)
Desmedt, Yvo; Lange, Tanja; Burmester, Mike
Task-specific groups are often formed in an ad-hoc manner within large corporate structures, such as companies. Take the following typical scenario: A director decides to set up a task force group for some specific project. An order is passed down the hierarchy where it finally reaches a manager who selects some employees to form the group. The members should communicate in a secure way and for efficiency, a symmetric encryption system is chosen. To establish a joint secret key for the group, a group key exchange (GKE) protocol is used. We show how to use an existing Public Key Infrastructure (PKI) to achieve authenticated GKE by modifying the protocol and particularly by including signatures.
Testing messages to reduce smokers' openness to using novel smokeless tobacco products.
Popova, Lucy; Neilands, Torsten B; Ling, Pamela M
2014-07-01
Tobacco manufacturers' aggressive promotion of new smokeless tobacco products such as snus warrants a timely and effective public health response. This study tested potential countermarketing messages to discourage current and former smokers from becoming dual users of smokeless tobacco and cigarettes. In a pretest-post-test experiment, 1836 adult current and recently former smokers from a national sample were randomised to view one of six antismokeless tobacco ads followed by a snus ad, to view a control ad followed by a snus ad; or to view two control ads. Perceived effectiveness of ads and actual changes in attitudes and openness to snus were compared across groups using analyses of variance. Some ads that were perceived as most effective did not change attitudes or openness to trying snus, and conversely, some ads not perceived as effective changed attitudes and openness to snus. Ads portraying the negative health effects of smokeless tobacco were perceived as most effective, but ads with antitobacco industry themes significantly decreased favourable attitudes toward snus. Responses to ads were different for smokers who had ever used smokeless tobacco: for this group health effects and humorous/testimonial ads were effective. Measures of perceived effectiveness of antitobacco ads need to be augmented with measures of actual effectiveness to assess countermarketing messages. Some of the developed ads, such as ads with anti-industry themes, were effective for the overall population of smokers whereas humorous/testimonial and health effects ads were particularly effective in changing attitudes of past users of smokeless tobacco. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Direct-to-consumer print ads for drugs: do they undermine the physician-patient relationship?
Cline, Rebecca J Welch; Young, Henry J
2005-12-01
Critics of direct-to-consumer print advertising for drugs (DTCA) contend it alters physician-patient communication by promoting greater patient participation and control. We assessed the nature of messages in print DTCA to identify potential guidelines they may provide to consumers for communicating with physicians. We analyzed all unique advertisements (ie, excluded ads repeated across issues or magazines) in 18 popular magazines (684 issues) from January 1998 to December 1999 (n=225). We identified every statement that referred to physicians, and within that set, statements that focused on physician-patient communication. Each communication-related statement was coded as a message to consumers about communication in terms of cues suggesting who should initiate communication, who should be in relational control, and appropriate interaction topic(s). More than three-quarters (83.8%) of the advertisements' statements referring to physicians focused on physician-patient communication (M=2.6 per ad; SD=1.8). Most (76.1%) of these messages explicitly or implicitly promoted consumers initiating communication, but cast the physician in relational control (54.5%). The most frequently suggested interaction topics were clinical judgments of the product's appropriateness (41.8%) and information about the product (32.1%). Typical direct-to-consumer print ads contain multiple messages about communicating with physicians. The patterned nature of these messages appears to promote social norms for consumers' communication behavior by repeatedly implying the appropriateness of consumers initiating interaction, physicians maintaining relational control, and avoiding negative consequences of advertised drugs as conversational topics.
Energy conservation in ad hoc multimedia networks using traffic-shaping mechanisms
NASA Astrophysics Data System (ADS)
Chandra, Surendar
2003-12-01
In this work, we explore network traffic shaping mechanisms that deliver packets at pre-determined intervals; allowing the network interface to transition to a lower power consuming sleep state. We focus our efforts on commodity devices, IEEE 802.11b ad hoc mode and popular streaming formats. We argue that factors such as the lack of scheduling clock phase synchronization among the participants and scheduling delays introduced by back ground tasks affect the potential energy savings. Increasing the periodic transmission delays to transmit data infrequently can offset some of these effects at the expense of flooding the wireless channel for longer periods of time; potentially increasing the time to acquire the channel for non-multimedia traffic. Buffering mechanisms built into media browsers can mitigate the effects of these added delays from being mis-interpreted as network congestion. We show that practical implementations of such traffic shaping mechanisms can offer significant energy savings.
A Game Theory Based Solution for Security Challenges in CRNs
NASA Astrophysics Data System (ADS)
Poonam; Nagpal, Chander Kumar
2018-03-01
Cognitive radio networks (CRNs) are being envisioned to drive the next generation Ad hoc wireless networks due to their ability to provide communications resilience in continuously changing environments through the use of dynamic spectrum access. Conventionally CRNs are dependent upon the information gathered by other secondary users to ensure the accuracy of spectrum sensing making them vulnerable to security attacks leading to the need of security mechanisms like cryptography and trust. However, a typical cryptography based solution is not a viable security solution for CRNs owing to their limited resources. Effectiveness of trust based approaches has always been, in question, due to credibility of secondary trust resources. Game theory with its ability to optimize in an environment of conflicting interests can be quite a suitable tool to manage an ad hoc network in the presence of autonomous selfish/malevolent/malicious and attacker nodes. The literature contains several theoretical proposals for augmenting game theory in the ad hoc networks without explicit/detailed implementation. This paper implements a game theory based solution in MATLAB-2015 to secure the CRN environment and compares the obtained results with the traditional approaches of trust and cryptography. The simulation result indicates that as the time progresses the game theory performs much better with higher throughput, lower jitter and better identification of selfish/malicious nodes.
Illing, R O; Clark, C L Ingham; Allum, C
2010-04-01
To review the provision of out-of-hours interventional radiology (IR) services in the London Strategic Health Authority (SHA). All 29 acute hospitals in the London SHA were contacted between November 2008 and January 2009. A questionnaire based on the Royal College of Radiologists (RCR) guidelines assessed the provision of out-of-hours IR services. An "ad-hoc" service was defined as on-call provision where not all the radiologists could perform intervention: If IR was required out of hours, an interventionalist came in when off-duty or the patient was transferred. Seventeen out of the 29 (59%) hospitals provided ad-hoc out-of-hours services, eight (28%) provided a 24-hour rota, and four (14%) provide no out-of-hours cover. No ad-hoc service had formal transfer arrangements to a centre providing a 24h service. Only two hospitals providing a 24h service had six radiologists on the rota. Strategic planning for out-of-hours IR across London is recommended. This is likely to be welcomed by the hospitals involved, allowing informal arrangements to be formalized, and collaboration to provide comprehensive regional networks, provided appropriate funding is made available. A national audit is recommended; it is unlikely these findings are unique to London.
Reliable Geographical Forwarding in Cognitive Radio Sensor Networks Using Virtual Clusters
Zubair, Suleiman; Fisal, Norsheila
2014-01-01
The need for implementing reliable data transfer in resource-constrained cognitive radio ad hoc networks is still an open issue in the research community. Although geographical forwarding schemes are characterized by their low overhead and efficiency in reliable data transfer in traditional wireless sensor network, this potential is still yet to be utilized for viable routing options in resource-constrained cognitive radio ad hoc networks in the presence of lossy links. In this paper, a novel geographical forwarding technique that does not restrict the choice of the next hop to the nodes in the selected route is presented. This is achieved by the creation of virtual clusters based on spectrum correlation from which the next hop choice is made based on link quality. The design maximizes the use of idle listening and receiver contention prioritization for energy efficiency, the avoidance of routing hot spots and stability. The validation result, which closely follows the simulation result, shows that the developed scheme can make more advancement to the sink as against the usual decisions of relevant ad hoc on-demand distance vector route select operations, while ensuring channel quality. Further simulation results have shown the enhanced reliability, lower latency and energy efficiency of the presented scheme. PMID:24854362
Energy-Aware Multipath Routing Scheme Based on Particle Swarm Optimization in Mobile Ad Hoc Networks
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. PMID:26819966
Designing integrated computational biology pipelines visually.
Jamil, Hasan M
2013-01-01
The long-term cost of developing and maintaining a computational pipeline that depends upon data integration and sophisticated workflow logic is too high to even contemplate "what if" or ad hoc type queries. In this paper, we introduce a novel application building interface for computational biology research, called VizBuilder, by leveraging a recent query language called BioFlow for life sciences databases. Using VizBuilder, it is now possible to develop ad hoc complex computational biology applications at throw away costs. The underlying query language supports data integration and workflow construction almost transparently and fully automatically, using a best effort approach. Users express their application by drawing it with VizBuilder icons and connecting them in a meaningful way. Completed applications are compiled and translated as BioFlow queries for execution by the data management system LifeDB, for which VizBuilder serves as a front end. We discuss VizBuilder features and functionalities in the context of a real life application after we briefly introduce BioFlow. The architecture and design principles of VizBuilder are also discussed. Finally, we outline future extensions of VizBuilder. To our knowledge, VizBuilder is a unique system that allows visually designing computational biology pipelines involving distributed and heterogeneous resources in an ad hoc manner.
Verspoor, E; Knox, D; Marshall, S
2016-12-01
An eclectic set of tissues and existing data, including purposely collected samples, spanning 1997-2006, was used in an ad hoc assessment of hybridization and introgression of farmed wild Atlantic salmon Salmo salar in the small Loch na Thull (LnT) catchment in north-west Scotland. The catchment is in an area of marine farm production and contains freshwater smolt rearing cages. The LnT S. salar stock was found to be genetically distinctive from stocks in neighbouring rivers and, despite regular reports of feral farm S. salar, there was no evidence of physical or genetic mixing. This cannot be completely ruled out, however, and low level mixing with other local wild stocks has been suggested. The LnT population appeared underpinned by relatively smaller effective number of breeders (N eb ) and showed relatively low levels of genetic diversity, consistent with a small effective population size. Small sample sizes, an incomplete farm baseline and the use of non-diagnostic molecular markers, constrain the power of the analysis but the findings strongly support the LnT catchment having a genetically distinct wild S. salar population little affected by interbreeding with feral farm escapes. © 2016 The Fisheries Society of the British Isles.
Tang, J. Y.; Riley, W. J.
2016-02-05
We present a generic flux limiter to account for mass limitations from an arbitrary number of substrates in a biogeochemical reaction network. The flux limiter is based on the observation that substrate (e.g., nitrogen, phosphorus) limitation in biogeochemical models can be represented as to ensure mass conservative and non-negative numerical solutions to the governing ordinary differential equations. Application of the flux limiter includes two steps: (1) formulation of the biogeochemical processes with a matrix of stoichiometric coefficients and (2) application of Liebig's law of the minimum using the dynamic stoichiometric relationship of the reactants. This approach contrasts with the ad hoc down-regulationmore » approaches that are implemented in many existing models (such as CLM4.5 and the ACME (Accelerated Climate Modeling for Energy) Land Model (ALM)) of carbon and nutrient interactions, which are error prone when adding new processes, even for experienced modelers. Through an example implementation with a CENTURY-like decomposition model that includes carbon, nitrogen, and phosphorus, we show that our approach (1) produced almost identical results to that from the ad hoc down-regulation approaches under non-limiting nutrient conditions, (2) properly resolved the negative solutions under substrate-limited conditions where the simple clipping approach failed, (3) successfully avoided the potential conceptual ambiguities that are implied by those ad hoc down-regulation approaches. We expect our approach will make future biogeochemical models easier to improve and more robust.« less
Basic Functional Capabilities for a Military Message Processing Service
1974-09-01
AD-AiI1 166 BASIC FUNCTIONA’. CAPABILITIES FOR A MILITARY MESSAGE PROCESSING SERVICE Ronald Tugender, et al University of Southern California...Itte) S. TYPE OF REPORT & PERIOD COVERED BASIC FUNCTIONAL CAPABILITIES FOR A Research Report MILITARY MESSAGE PROCESSING SERVICE 6. PERFORMING ONG...WOROD (Conionwo m trevre aide If tneeoooy arm idmentify by egekA INber) automated message processing , command and control, writer-to-reader service
Lin, Chia-Yen; Yeh, Wei-Ju
2017-01-01
The health costs of colorectal cancer have increased over the years in Taiwan. The National Health Insurance Administration (NHI) and the Health Promotion Administration of the Ministry of Health and Welfare (MOHW) in Taiwan advocate that people have to change their unhealthy behaviors; however, the number of patients of colorectal cancer is increasing annually. This research discussed the effects of healthy diet advocacy advertisements (ads) on healthy diet behavior intentions as influenced by the interactions between regulatory focus theory (RFT) and message framing effects. Both regulatory focus theory and message framing effect were discussed for the relationship between advertisement and behavior change in many fields, such as health-related behavior, pro-environmental behavior, consumer choice, etc. We executed an experiment with four different types of public health advocacy ads. A 2 (regulatory focus: promotion vs. prevention) × 2 (message framing: gain framing vs. loss framing) two-factor experiment was adopted, and 201 valid participants responded to the questionnaire. Results indicated that if the ad’s regulatory focus is promotion focus, viewers’ attitudes toward the ad and their behavior intentions are more positive when the slogan of the ad is gain framing rather than loss framing via the multiple analysis of variance (MANOVA), and vice versa. Respondents found the communication easier to comprehend when the ads evoked the respondents’ regulatory focus and applied the appropriate message framing, thus improving the efficacy of health-related advertising. We offer suggestions regarding the future use of health-related advertising for the MOHW. PMID:29207544
Cheng, Benjamin Ka Lun
2015-01-01
This study adopts the regulatory fit theory and examines the effects of the celebrity and message fit on children's responses to the promotion of healthy eating. A 2 × 2 experiment was conducted with 87 Hong Kong children ages 11 to 16. The results showed that a regulatory fit between the celebrity focus and the message focus yielded a better affective response. Specifically, children found a poster ad more convincing, liked it more, held more positive feelings, and found the poster ad more interesting in the fit conditions. Implications and future research directions were discussed.
Intelligent routing protocol for ad hoc wireless network
NASA Astrophysics Data System (ADS)
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 mechanisms, which are used to control active route and reduce the traffic amount in the route discovery procedure. Finial, the numerical experiments are given to show the effectiveness of IRP routing protocol.
Effects of E-cigarette Advertising Messages and Cues on Cessation Outcomes
Jo, Catherine L.; Golden, Shelley D.; Noar, Seth M.; Rini, Christine; Ribisl, Kurt M.
2017-01-01
Objectives We examined effects of e-cigarette ad messages and visual cues on outcomes related to combustible cigarette smoking cessation: smoking cessation intention, smoking urges, and immediate smoking behavior. Methods US adult smokers (N = 3293) were recruited through Amazon Mechanical Turk and randomized to condition in a 3 (message: e-cigarette use anywhere, harm reduction, control) × 2 (e-cigarette cue presence or absence) between-subjects experiment. Stimuli were print ads for cigarette-like e-cigarettes (“cigalikes”) that were manipulated for the experimental conditions. We conducted ANOVA and logistic regression analyses to investigate effects of the manipulations. Results Message effects on cessation intention and smoking urges were not statistically significant. There was no evidence of cue effects or message × cue interactions across outcomes. Contrary to expectations, e-cigarette use anywhere and harm reduction messages were associated with lower odds of immediate smoking than the control message (AOREUA = 0.75, 95%CI = 0.58, 0.97, p = .026; AORHR = 0.72, 95%CI = 0.55, 0.93, p = .013). Conclusions E-cigarette use anywhere and harm reduction messages may encourage smoking cessation, given the observed reduction in immediate smoking. E-cigarette cues may not influence smoking cessation outcomes. Future studies should investigate whether message effects are a result of smokers believing e-cigarettes to be effective cessation aids. PMID:29242819
What makes an ad a cigarette ad? Commercial tobacco imagery in the lesbian, gay, and bisexual press
Smith, E.; Offen, N.; Malone, R.
2005-01-01
Objectives: To determine the extent of commercial tobacco imagery in the lesbian, gay, and bisexual (LGB) press. Methods: Content analysis of all advertising containing tobacco related text or imagery in 20 LGB community periodicals, published between January 1990 and December 2000. Results: 3428 ads were found: 689 tobacco product ads, 1607 ads for cessation products or services, 99 ads with a political message about tobacco, and 1033 non-tobacco ads that showed tobacco (NAST). Although cessation ads were numerically dominant, tobacco product ads and NAST occupied more space and were more likely to use images. NAST almost never had an anti-tobacco message. Formal sponsorship between tobacco and other companies was very rare. Lesbian periodicals had proportionally more NAST and fewer cessation ads. Conclusions: Cigarette ads were outnumbered by NAST. Although these ads do not usually show brands, and are unlikely to be the result of formal sponsorship agreements, they may be "selling" smoking. Tobacco control advocates should persuade editors to refuse tobacco product ads and those with gratuitous tobacco imagery. PMID:16286500
An adaptive density-based routing protocol for flying Ad Hoc networks
NASA Astrophysics Data System (ADS)
Zheng, Xueli; Qi, Qian; Wang, Qingwen; Li, Yongqiang
2017-10-01
An Adaptive Density-based Routing Protocol (ADRP) for Flying Ad Hoc Networks (FANETs) is proposed in this paper. The main objective is to calculate forwarding probability adaptively in order to increase the efficiency of forwarding in FANETs. ADRP dynamically fine-tunes the rebroadcasting probability of a node for routing request packets according to the number of neighbour nodes. Indeed, it is more interesting to privilege the retransmission by nodes with little neighbour nodes. We describe the protocol, implement it and evaluate its performance using NS-2 network simulator. Simulation results reveal that ADRP achieves better performance in terms of the packet delivery fraction, average end-to-end delay, normalized routing load, normalized MAC load and throughput, which is respectively compared with AODV.
Topology for efficient information dissemination in ad-hoc networking
NASA Technical Reports Server (NTRS)
Jennings, E.; Okino, C. M.
2002-01-01
In this paper, we explore the information dissemination problem in ad-hoc wirless networks. First, we analyze the probability of successful broadcast, assuming: the nodes are uniformly distributed, the available area has a lower bould relative to the total number of nodes, and there is zero knowledge of the overall topology of the network. By showing that the probability of such events is small, we are motivated to extract good graph topologies to minimize the overall transmissions. Three algorithms are used to generate topologies of the network with guaranteed connectivity. These are the minimum radius graph, the relative neighborhood graph and the minimum spanning tree. Our simulation shows that the relative neighborhood graph has certain good graph properties, which makes it suitable for efficient information dissemination.
An enhanced performance through agent-based secure approach for mobile ad hoc networks
NASA Astrophysics Data System (ADS)
Bisen, Dhananjay; Sharma, Sanjeev
2018-01-01
This paper proposes an agent-based secure enhanced performance approach (AB-SEP) for mobile ad hoc network. In this approach, agent nodes are selected through optimal node reliability as a factor. This factor is calculated on the basis of node performance features such as degree difference, normalised distance value, energy level, mobility and optimal hello interval of node. After selection of agent nodes, a procedure of malicious behaviour detection is performed using fuzzy-based secure architecture (FBSA). To evaluate the performance of the proposed approach, comparative analysis is done with conventional schemes using performance parameters such as packet delivery ratio, throughput, total packet forwarding, network overhead, end-to-end delay and percentage of malicious detection.
Application of Game Theory Approaches in Routing Protocols for Wireless Networks
NASA Astrophysics Data System (ADS)
Javidi, Mohammad M.; Aliahmadipour, Laya
2011-09-01
An important and essential issue for wireless networks is routing protocol design that is a major technical challenge due to the function of the network. Game theory is a powerful mathematical tool that analyzes the strategic interactions among multiple decision makers and the results of researches show that applied game theory in routing protocol lead to improvement the network performance through reduce overhead and motivates selfish nodes to collaborate in the network. This paper presents a review and comparison for typical representatives of routing protocols designed that applied game theory approaches for various wireless networks such as ad hoc networks, mobile ad hoc networks and sensor networks that all of them lead to improve the network performance.
Protocol Independent Adaptive Route Update for VANET
Rasheed, Asim; Qayyum, Amir
2014-01-01
High relative node velocity and high active node density have presented challenges to existing routing approaches within highly scaled ad hoc wireless networks, such as Vehicular Ad hoc Networks (VANET). Efficient routing requires finding optimum route with minimum delay, updating it on availability of a better one, and repairing it on link breakages. Current routing protocols are generally focused on finding and maintaining an efficient route, with very less emphasis on route update. Adaptive route update usually becomes impractical for dense networks due to large routing overheads. This paper presents an adaptive route update approach which can provide solution for any baseline routing protocol. The proposed adaptation eliminates the classification of reactive and proactive by categorizing them as logical conditions to find and update the route. PMID:24723807
Corredor, Iván; Metola, Eduardo; Bernardos, Ana M; Tarrío, Paula; Casar, José R
2014-04-29
In the last few years, many health monitoring systems have been designed to fullfil the needs of a large range of scenarios. Although many of those systems provide good ad hoc solutions, most of them lack of mechanisms that allow them to be easily reused. This paper is focused on describing an open platform, the micro Web of Things Open Platform (µWoTOP), which has been conceived to improve the connectivity and reusability of context data to deliver different kinds of health, wellness and ambient home care services. µWoTOP is based on a resource-oriented architecture which may be embedded in mobile and resource constrained devices enabling access to biometric, ambient or activity sensors and actuator resources through uniform interfaces defined according to a RESTful fashion. Additionally, µWoTOP manages two communication modes which allow delivering user context information according to different methods, depending on the requirements of the consumer application. It also generates alert messages based on standards related to health care and risk management, such as the Common Alerting Protocol, in order to make its outputs compatible with existing systems.
Corredor, Iván; Metola, Eduardo; Bernardos, Ana M.; Tarrío, Paula; Casar, José R.
2014-01-01
In the last few years, many health monitoring systems have been designed to fullfil the needs of a large range of scenarios. Although many of those systems provide good ad hoc solutions, most of them lack of mechanisms that allow them to be easily reused. This paper is focused on describing an open platform, the micro Web of Things Open Platform (µWoTOP), which has been conceived to improve the connectivity and reusability of context data to deliver different kinds of health, wellness and ambient home care services. µWoTOP is based on a resource-oriented architecture which may be embedded in mobile and resource constrained devices enabling access to biometric, ambient or activity sensors and actuator resources through uniform interfaces defined according to a RESTful fashion. Additionally, µWoTOP manages two communication modes which allow delivering user context information according to different methods, depending on the requirements of the consumer application. It also generates alert messages based on standards related to health care and risk management, such as the Common Alerting Protocol, in order to make its outputs compatible with existing systems. PMID:24785542
Lightweight and scalable secure communication in VANET
NASA Astrophysics Data System (ADS)
Zhu, Xiaoling; Lu, Yang; Zhu, Xiaojuan; Qiu, Shuwei
2015-05-01
To avoid a message to be tempered and forged in vehicular ad hoc network (VANET), the digital signature method is adopted by IEEE1609.2. However, the costs of the method are excessively high for large-scale networks. The paper efficiently copes with the issue with a secure communication framework by introducing some lightweight cryptography primitives. In our framework, point-to-point and broadcast communications for vehicle-to-infrastructure (V2I) and vehicle-to-vehicle (V2V) are studied, mainly based on symmetric cryptography. A new issue incurred is symmetric key management. Thus, we develop key distribution and agreement protocols for two-party key and group key under different environments, whether a road side unit (RSU) is deployed or not. The analysis shows that our protocols provide confidentiality, authentication, perfect forward secrecy, forward secrecy and backward secrecy. The proposed group key agreement protocol especially solves the key leak problem caused by members joining or leaving in existing key agreement protocols. Due to aggregated signature and substitution of XOR for point addition, the average computation and communication costs do not significantly increase with the increase in the number of vehicles; hence, our framework provides good scalability.
A New Approach to Predict user Mobility Using Semantic Analysis and Machine Learning.
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.
Increasing the reliability of ecological models using modern software engineering techniques
Robert M. Scheller; Brian R. Sturtevant; Eric J. Gustafson; Brendan C. Ward; David J. Mladenoff
2009-01-01
Modern software development techniques are largely unknown to ecologists. Typically, ecological models and other software tools are developed for limited research purposes, and additional capabilities are added later, usually in an ad hoc manner. Modern software engineering techniques can substantially increase scientific rigor and confidence in ecological models and...
Messages in alcohol advertising targeted to youth.
Jones, S C; Donovan, R J
2001-04-01
To assess young people's perceived messages in three ads for a vodka-based, pre-mixed alcohol beverage, and to assess the extent to which the ads appeared to be consistent with the industry's voluntary code. Members of two convenience samples of young people (15-16 and 19-21 years) were each exposed to one of three advertisements. Respondents completed a post exposure questionnaire based on standard advertising copy testing procedures. The most frequently nominated open-ended responses to 'the main message(s) of the ad' related to the product delivering mood effects: both removal of negative emotions (e.g. 'stress reduction'), as well as inducing positive states such as feeling 'carefree' and gaining 'increased enjoyment'. Consumption of the product was perceived to offer 'self-confidence', 'sexual/relationship success' and 'social success'. Fewer respondents nominated tangible product characteristics, the main one being 'easy to drink'. One in four of the 15-16 year olds saw the ads as aimed at 'people my age', while almost half of the 19-21 year olds saw the ads as aimed at 'people younger or much younger than me'. These results appear to contravene the Alcoholic Beverages Advertising Code (ABAC) by suggesting that the consumption of alcohol beverages: (i) contributes to social and sexual success; and (ii) contributes to a significant change in mood (stress reduction/relaxation). Incidental observation of alcohol ads suggests that contravention of the code is more widespread than the number of alcohol advertising complaints would indicate. All 11 such complaints lodged with the Advertising Standards Board between May 1998 and April 1999 were dismissed. Evidence such as that gathered in this study might improve the chances of complaints being upheld.
Applying Ad Hoc Institutional Research Findings to College Strategic Planning
ERIC Educational Resources Information Center
Clagett, Craig A.
2004-01-01
Environmental scanning, enrollment forecasting, budget analyses, and institutional effectiveness assessment are examples of the explicit contributions institutional research offices make to campus strategic planning.
Messages to new mothers: an analysis of breast pump advertisements.
Sheehan, Athena; Bowcher, Wendy L
2017-04-01
The mass media is replete with all kinds of advice, products and ideas about 'motherhood' with advertising being a major source of information on the latest products and consumer trends. Advertising is a key means of promoting ideas about infant feeding, and yet, there has been little in the way of critical analyses of breast pump advertisements in order to reveal the kinds of messages they convey about this method of feeding. This article makes an important step towards addressing this gap through analysing three advertisements for breast pumps from a popular Australian magazine for mothers. We utilize a social semiotic framework to investigate not just what choices are made in the design of the ads but also what those choices mean in terms of the overall message of the ads. Our analysis identifies three core messages: 'breastfeeding and breast pumping are the same with the purpose being to produce breast milk only', 'using breast pumps facilitates quality time with the baby' and 'mothers need outside expertise (including breast pumps) to ensure baby's development'. We believe it is important for those who provide information and support for breastfeeding women to be aware of the subtle, naturalized messages that ads convey so that they may better understand what may be underlying women's decisions regarding methods of infant feeding. © 2016 John Wiley & Sons Ltd. © 2016 John Wiley & Sons Ltd.
Duke, Jennifer C.; Allen, Jane Appleyard; Pederson, Linda L.; Mowery, Paul D.; Xiao, Haijun; Sargent, James D.
2015-01-01
Purpose Document changes from 2000 to 2004 in youth reports of exposure to pro-tobacco messages in the mass media, including images of smoking and tobacco advertising. Design Comparison of cross-sectional data from three waves of the school-based National Youth Tobacco Surveys conducted in 2000 (N = 33,772), 2002 (N = 23,439), and 2004 (N = 23,540). Setting Public and private middle schools and high schools across the United States. Subjects Students in grades 6 through 12. Measures Smoking status; exposure to images of smoking on television and in movies; exposure to advertisements for tobacco products in stores, on the Internet, and in newspapers and magazines; demographic data. Results Youth exposure to pro-tobacco messages declined within all media channels studied from 2000 to 2004, except the Internet. Despite these declines, most youth in the United States remain exposed to pro-tobacco messages: 81% saw images of smoking on television or in movies (down from 90%), 85% saw tobacco ads in stores (down from 88%), 50% saw tobacco ads in newspapers and magazines (down from 66%), and 33% saw tobacco ads on the Internet (up from 22%). Conclusion Despite recent progress in this area, most youth in the United States are still at increased risk of smoking as a result of exposure to pro-tobacco messages in the mass media. PMID:19149425
Duke, Jennifer C; Allen, Jane Appleyard; Pederson, Linda L; Mowery, Paul D; Xiao, Haijun; Sargent, James D
2009-01-01
Document changes from 2000 to 2004 in youth reports of exposure to pro-tobacco messages in the mass media, including images of smoking and tobacco advertising. Comparison of cross-sectional data from three waves of the school-based National Youth Tobacco Surveys conducted in 2000 (N= 33,772), 2002 (N= 23,439), and 2004 (N= 23,540). Public and private middle schools and high schools across the United States. Students in grades 6 through 12. Smoking status; exposure to images of smoking on television and in movies; exposure to advertisements for tobacco products in stores, on the Internet, and in newspapers and magazines; demographic data. Youth exposure to pro-tobacco messages declined within all media channels studied from 2000 to 2004, except the Internet. Despite these declines, most youth in the United States remain exposed to pro-tobacco messages: 81% saw images of smoking on television or in movies (down from 90%), 85% saw tobacco ads in stores (down from 88%), 50% saw tobacco ads in newspapers and magazines (down from 66%), and 33 % saw tobacco ads on the Internet (up from 22%). Despite recent progress in this area, most youth in the United States are still at increased risk of smoking as a result of exposure to pro-tobacco messages in the mass media.
ERIC Educational Resources Information Center
Lillie, Richard E.; Liu, Xiang; Kang, Gerui
2011-01-01
Eyejot, a free video email service, makes it possible to create, send, and receive video messages over the Internet. By adding the warmth of face-to-face interaction to the traditional email message, Eyejot creates a more interactive form of communication that engages today's techsavvy students. This paper shares our experience using Eyejot to…
2013-01-01
Background Clinical Intelligence, as a research and engineering discipline, is dedicated to the development of tools for data analysis for the purposes of clinical research, surveillance, and effective health care management. Self-service ad hoc querying of clinical data is one desirable type of functionality. Since most of the data are currently stored in relational or similar form, ad hoc querying is problematic as it requires specialised technical skills and the knowledge of particular data schemas. Results A possible solution is semantic querying where the user formulates queries in terms of domain ontologies that are much easier to navigate and comprehend than data schemas. In this article, we are exploring the possibility of using SADI Semantic Web services for semantic querying of clinical data. We have developed a prototype of a semantic querying infrastructure for the surveillance of, and research on, hospital-acquired infections. Conclusions Our results suggest that SADI can support ad-hoc, self-service, semantic queries of relational data in a Clinical Intelligence context. The use of SADI compares favourably with approaches based on declarative semantic mappings from data schemas to ontologies, such as query rewriting and RDFizing by materialisation, because it can easily cope with situations when (i) some computation is required to turn relational data into RDF or OWL, e.g., to implement temporal reasoning, or (ii) integration with external data sources is necessary. PMID:23497556
A Source Anonymity-Based Lightweight Secure AODV Protocol for Fog-Based MANET
Fang, Weidong; Zhang, Wuxiong; Xiao, Jinchao; Yang, Yang; Chen, Wei
2017-01-01
Fog-based MANET (Mobile Ad hoc networks) is a novel paradigm of a mobile ad hoc network with the advantages of both mobility and fog computing. Meanwhile, as traditional routing protocol, ad hoc on-demand distance vector (AODV) routing protocol has been applied widely in fog-based MANET. Currently, how to improve the transmission performance and enhance security are the two major aspects in AODV’s research field. However, the researches on joint energy efficiency and security seem to be seldom considered. In this paper, we propose a source anonymity-based lightweight secure AODV (SAL-SAODV) routing protocol to meet the above requirements. In SAL-SAODV protocol, source anonymous and secure transmitting schemes are proposed and applied. The scheme involves the following three parts: the source anonymity algorithm is employed to achieve the source node, without being tracked and located; the improved secure scheme based on the polynomial of CRC-4 is applied to substitute the RSA digital signature of SAODV and guarantee the data integrity, in addition to reducing the computation and energy consumption; the random delayed transmitting scheme (RDTM) is implemented to separate the check code and transmitted data, and achieve tamper-proof results. The simulation results show that the comprehensive performance of the proposed SAL-SAODV is a trade-off of the transmission performance, energy efficiency, and security, and better than AODV and SAODV. PMID:28629142
A Feasible Approach for an Early Manned Lunar Landing. Part II: Detailed Report of Ad Hoc Task Group
NASA Technical Reports Server (NTRS)
Fleming, William A.
1961-01-01
This report, in two parts, presents a program development plan for attempting a first manned lunar landing in 1967. The two parts consist of a Summary Report and a Detailed Report representing the coordinated output of the Ad Hoc Task Group assigned to the study. The study was started in response to the request for such a study by the Associate Administrator in his memorandum of May 2, 1961 establishing the Ad Hoc Task Group. The purpose of the study was to take a first cut at the tasks associated with the design, development and construction of the equipment and facilities as well as the development of the crews, and to show the time phasing 6f these tasks. Included are the space sciences, life science and advanced technology tasks whose data and results are needed for designing and developing the systems required in carrying out the mission. The plan presented in the two reports does not presume to be a firm plan. Its basic purpose is, by choosing one feasible method, to size up the scope, schedule and cost of the job, discover the main problems, pacing items and major decisions and provide a threshold from which a firm and detailed project development plan can be jointly formulated by the various elements of NASA.
A Source Anonymity-Based Lightweight Secure AODV Protocol for Fog-Based MANET.
Fang, Weidong; Zhang, Wuxiong; Xiao, Jinchao; Yang, Yang; Chen, Wei
2017-06-17
Fog-based MANET (Mobile Ad hoc networks) is a novel paradigm of a mobile ad hoc network with the advantages of both mobility and fog computing. Meanwhile, as traditional routing protocol, ad hoc on-demand distance vector (AODV) routing protocol has been applied widely in fog-based MANET. Currently, how to improve the transmission performance and enhance security are the two major aspects in AODV's research field. However, the researches on joint energy efficiency and security seem to be seldom considered. In this paper, we propose a source anonymity-based lightweight secure AODV (SAL-SAODV) routing protocol to meet the above requirements. In SAL-SAODV protocol, source anonymous and secure transmitting schemes are proposed and applied. The scheme involves the following three parts: the source anonymity algorithm is employed to achieve the source node, without being tracked and located; the improved secure scheme based on the polynomial of CRC-4 is applied to substitute the RSA digital signature of SAODV and guarantee the data integrity, in addition to reducing the computation and energy consumption; the random delayed transmitting scheme (RDTM) is implemented to separate the check code and transmitted data, and achieve tamper-proof results. The simulation results show that the comprehensive performance of the proposed SAL-SAODV is a trade-off of the transmission performance, energy efficiency, and security, and better than AODV and SAODV.
Linking Satellites Via Earth "Hot Spots" and the Internet to Form Ad Hoc Constellations
NASA Technical Reports Server (NTRS)
Mandl, Dan; Frye, Stu; Grosvenor, Sandra; Ingram, Mary Ann; Langley, John; Miranda, Felix; Lee, Richard Q.; Romanofsky, Robert; Zaman, Afoz; Popovic, Zoya
2004-01-01
As more assets are placed in orbit, opportunities emerge to combine various sets of satellites in temporary constellations to perform collaborative image collections. Often, new operations concepts for a satellite or set of satellites emerge after launch. To the degree with which new space assets can be inexpensively and rapidly integrated into temporary or "ad hoc" constellations, will determine whether these new ideas will be implemented or not. On the Earth Observing 1 (EO-1) satellite, a New Millennium Program mission, a number of experiments were conducted and are being conducted to demonstrate various aspects of an architecture that, when taken as a whole, will enable progressive mission autonomy. In particular, the target architecture will use adaptive ground antenna arrays to form, as close as possible, the equivalent of wireless access points for low earth orbiting satellites. Coupled with various ground and flight software and the Internet. the architecture enables progressive mission autonomy. Thus, new collaborative sensing techniques can be implemented post-launch. This paper will outline the overall operations concept and highlight details of both the research effort being conducted in
Biener, Lois; Ji, Ming; Gilpin, Elizabeth A; Albers, Alison B
2004-01-01
In the context of controversy regarding the optimal characteristics of anti-smoking advertisements for youth, this study examines the impact on recall and perceived effectiveness of variations in the message, emotional tone, reach and frequency of broadcast, remoteness of broadcast, and characteristics of the adolescent audience such as changes in smoking behavior, ownership of cigarette promotional items, and demographic variables. A two-wave longitudinal survey of a population-based sample of 618 Massachusetts youth 12 to 15 years old was carried out in 1993 and 1997. A Generalized Estimating Equation (GEE) approach was used to model the recall and perceived effectiveness of eight advertisements as a function of viewer and ad characteristics. Advertisements featuring messages about serious health consequences which had been independently rated as high in negative emotion were more likely to be recalled and were perceived as more effective by youth survey respondents than ads featuring messages about normative behavior for teens or ads relying on humor. Advertising intensity, while contributing to recall, was negatively related to perceived effectiveness. This study supports mounting evidence that negative emotion in anti-smoking advertisements is effective with youth audiences.
What defines an effective anti-tobacco TV advertisement? A pilot study among Greek adolescents.
Vardavas, Constantine I; Symvoulakis, Emmanouil K; Connolly, Gregory N; Patelarou, Evridiki; Lionis, Christos
2010-01-01
As the Framework Convention on Tobacco Control (FCTC) calls for public health awareness on tobacco use, mass media campaigns should be appropriately designed so as to maximize their effectiveness. In this methodological pilot study, 95 Greek adolescents (mean age 15 +/- 1.8 years), were shown seven different anti tobacco ads, and asked to rate the ad theme, message and emotional context on a 1-7 Likert scale. Health related ads were rated the highest, and as identified through the logistic regression analysis, adolescents who perceived an ad to be emotional or to have a clear message that was relevant to them, were more likely to rate the ad as more effective. The strong agreement between the above findings and the existing literature indicates the applicability of this pilot study's methodological approach.
Proctor, Dwayne C; Babor, Thomas F; Xuan, Ziming
2005-09-01
This study examined how individual difference vulnerability factors affect college students' perceptions of beer commercial actors' age, attractiveness and drinking. We were also interested in whether viewers' exposure to a cautionary message would affect their perceptions of the actors' drinking behavior. Three groups of college students were exposed to the same set of two alcohol advertisements. After watching the ads, each group received a different cautionary message prior to answering questions about the ad's content: (1) a neutral message (viewed by 42% [n = 119] of the sample), (2) a U.S. federal warning (viewed by 31% [n = 89]) and (3) an industry message (viewed by 27% [n = 76]). We also examined three putative vulnerability factors: age (underage 21 or not), gender and family history of alcohol problems (yes or no) as well as the effects of quantity-frequency of alcohol consumption, episodic heavy drinking, severity of alcohol dependence, disinhibition sensation seeking and the eight factors of the Alcohol Expectancy Scale. The cautionary messages had no effect on viewers' perceptions of characters' age, attractiveness and drinking behavior. Although neither of the commercials depicted the physical act of drinking, the student raters nevertheless perceived the characters to be heavy episodic drinkers. Those reporting more alcohol dependence symptoms perceived increased drinking for the male characters, as did females and viewers with expectancies for social and physical pleasure. Perceptions of the drinking in beer commercials are based in part on the character depicted in the ad and in part on the demographic and personal vulnerability factors of the viewer.
Durkin, Sarah; Bayly, Megan; Cotter, Trish; Mullin, Sandra; Wakefield, Melanie
2013-12-01
Unlike high income countries, there is limited research to guide selection of anti-tobacco mass media campaigns in low and middle income countries, although some work suggests that messages emphasizing serious health harms perform better than other message types. This study aimed to determine whether certain types of anti-smoking advertisements are more likely to be accepted and perceived as effective across smokers in 10 low to middle income countries. 2399 18-34 year old smokers were recruited in Bangladesh, China, Egypt, India, Indonesia, Mexico, Philippines, Russia, Turkey and Vietnam to view and rate 10 anti-tobacco ads. Five ads were shown in all countries and five ads were chosen by country representatives, providing a total of 37 anti-smoking ads across all countries (10 graphic health effects ads, 6 simulated health effects, 8 emotional stories of health effects, 7 other health effects and 6 non-health effects). Smokers rated ads on a series of 5-point scales containing aggregated measures of Message Acceptance and Perceived Effectiveness. All ads and materials were translated into the local language of the testing regions. In multivariate analysis, graphic health effects ads were most likely to be accepted and perceived as effective, followed by simulated health effects ads, health effects stories, other health effects ads, and then non-health effects ads. Interaction analyses indicated that graphic health effects ads were less likely to differ in acceptance or perceived effectiveness across countries, gender, age, education, parental status and amount smoked, and were less likely to be affected by cultural differences between characters and contexts in ads and those within each country. Ads that did not emphasize the health effects of smoking were most prone to inconsistent impact across countries and population subgroups. Graphic ads about the negative health effects of smoking may be most suitable for wide population broadcast in low and middle income countries. Copyright © 2013 Elsevier Ltd. All rights reserved.
Le, Daisy; Holt, Cheryl L; Saunders, Darlene R; Wang, Min Qi; Coriolan, Annie; Savoy, Alma D; Slade, Jimmie L; Muwwakkil, Bettye; Atkinson, Nancy L
2016-12-01
African Americans' greater access to mobile phones makes short messaging service technology a promising complement to health promotion interventions. Short messaging service text messages were added to the Men's Prostate Awareness Church Training project, a men's health intervention for African American men. We report on the feasibility and acceptability of the use of short messaging service text messages in the intervention. Short messaging service text messages served as (1) workshop reminders; (2) post-workshop message reinforcement; (3) spiritual/motivational messages; and (4) participant retention. At workshop 4, over 65 percent of participants wished to continue receiving the messages. While there was an increase in recall over time, more than one-third of the participants did not recall receiving the 53 text messages. However, recall was considerably greater among men who attended the Men's Prostate Awareness Church Training workshops. Overall, the inclusion of text messages in health promotion interventions targeting mature African American men was found to be feasible and acceptable. © The Author(s) 2015.
Research opportunities in cardiovascular deconditioning, phase 1
NASA Technical Reports Server (NTRS)
Levy, M. N. (Editor); Talbot, J. M. (Editor)
1983-01-01
The deconditioning of the cardiovascular system that occurs during spaceflight, NASA's current and projected research program, and the conclusions and suggestions of the ad hoc Working Group are summarized.
On service differentiation in mobile Ad Hoc networks.
Zhang, Shun-liang; Ye, Cheng-qing
2004-09-01
A network model is proposed to support service differentiation for mobile Ad Hoc networks by combining a fully distributed admission control approach and the DIFS based differentiation mechanism of IEEE802.11. It can provide different kinds of QoS (Quality of Service) for various applications. Admission controllers determine a committed bandwidth based on the reserved bandwidth of flows and the source utilization of networks. Packets are marked when entering into networks by markers according to the committed rate. By the mark in the packet header, intermediate nodes handle the received packets in different manners to provide applications with the QoS corresponding to the pre-negotiated profile. Extensive simulation experiments showed that the proposed mechanism can provide QoS guarantee to assured service traffic and increase the channel utilization of networks.
Immune Inspired Security Approach for Manets: a Case Study
NASA Astrophysics Data System (ADS)
Mohamed, Yasir Abdelgadir
2011-06-01
This paper extends the work that has earlier been established. Immune inspired approach for securing mobile ad hoc networks is specified there. Although it is clearly indicated there that the research scope is the wireless networks in general and hybrid mobile ad hoc networks in particular, we have seen that specifying the security system in one of the communications applications that need further security approach may help to understand how effectively the system can contribute to this vital and important networks sector. Security in this type of networks is important and controversial as it plays a key role in users' eagerness or reluctance for the services provided by these networks. In this paper, the immune inspired security system is specified to secure web services in converged networks.
A high performance, ad-hoc, fuzzy query processing system for relational databases
NASA Technical Reports Server (NTRS)
Mansfield, William H., Jr.; Fleischman, Robert M.
1992-01-01
Database queries involving imprecise or fuzzy predicates are currently an evolving area of academic and industrial research. Such queries place severe stress on the indexing and I/O subsystems of conventional database environments since they involve the search of large numbers of records. The Datacycle architecture and research prototype is a database environment that uses filtering technology to perform an efficient, exhaustive search of an entire database. It has recently been modified to include fuzzy predicates in its query processing. The approach obviates the need for complex index structures, provides unlimited query throughput, permits the use of ad-hoc fuzzy membership functions, and provides a deterministic response time largely independent of query complexity and load. This paper describes the Datacycle prototype implementation of fuzzy queries and some recent performance results.
NASA Astrophysics Data System (ADS)
Yu, Chih-Min; Huang, Chia-Chi
In this letter, a decentralized scatternet formation algorithm called Bluelayer is proposed. First, Bluelayer uses a designated root to construct a tree-shaped subnet and propagates an integer variable k1 called counter limit as well as a constant k in its downstream direction to determine new roots. Then each new root asks its upstream master to start a return connection procedure to convert the tree-shaped subnet into a web-shaped subnet for its immediate upstream root. At the same time, each new root repeats the same procedure as the root to build its own subnet until the whole scatternet is formed. Simulation results show that Bluelayer achieves good network scalability and generates an efficient scatternet configuration for various sizes of Bluetooth ad hoc network.
NASA Astrophysics Data System (ADS)
Shen, Feng; Wayn Cheong, Joon; Dempster, Andrew G.
2015-04-01
Relative position awareness is a vital premise for the implementation of emerging intelligent transportation systems, such as collision warning. However, commercial global navigation satellite systems (GNSS) receivers do not satisfy the requirements of these applications. Fortunately, cooperative positioning (CP) techniques, through sharing the GNSS measurements between vehicles, can improve the performance of relative positioning in a vehicular ad hoc network (VANET). In this paper, while assuming there are no obstacles between vehicles, a new enhanced tightly coupled CP technique is presented by adding ultra-wide bandwidth (UWB)-based inter-vehicular range measurements. In the proposed CP method, each vehicle fuses the GPS measurements and the inter-vehicular range measurements. Based on analytical and experimental results, in the full GPS coverage environment, the new tight integration CP method outperforms the INS-aided tight CP method, tight CP method, and DGPS by 11%, 15%, and 24%, respectively; in the GPS outage scenario, the performance improvement achieves 60%, 65%, and 73%, respectively.
NASA Astrophysics Data System (ADS)
Hortos, William S.
2003-07-01
Mobile ad hoc networking (MANET) supports self-organizing, mobile infrastructures and enables an autonomous network of mobile nodes that can operate without a wired backbone. Ad hoc networks are characterized by multihop, wireless connectivity via packet radios and by the need for efficient dynamic protocols. All routers are mobile and can establish connectivity with other nodes only when they are within transmission range. Importantly, ad hoc wireless nodes are resource-constrained, having limited processing, memory, and battery capacity. Delivery of high quality-ofservice (QoS), real-time multimedia services from Internet-based applications over a MANET is a challenge not yet achieved by proposed Internet Engineering Task Force (IETF) ad hoc network protocols in terms of standard performance metrics such as end-to-end throughput, packet error rate, and delay. In the distributed operations of route discovery and maintenance, strong interaction occurs across MANET protocol layers, in particular, the physical, media access control (MAC), network, and application layers. The QoS requirements are specified for the service classes by the application layer. The cross-layer design must also satisfy the battery-limited energy constraints, by minimizing the distributed power consumption at the nodes and of selected routes. Interactions across the layers are modeled in terms of the set of concatenated design parameters including associated energy costs. Functional dependencies of the QoS metrics are described in terms of the concatenated control parameters. New cross-layer designs are sought that optimize layer interdependencies to achieve the "best" QoS available in an energy-constrained, time-varying network. The protocol design, based on a reactive MANET protocol, adapts the provisioned QoS to dynamic network conditions and residual energy capacities. The cross-layer optimization is based on stochastic dynamic programming conditions derived from time-dependent models of MANET packet flows. Regulation of network behavior is modeled by the optimal control of the conditional rates of multivariate point processes (MVPPs); these rates depend on the concatenated control parameters through a change of probability measure. The MVPP models capture behavior of many service applications, e.g., voice, video and the self-similar behavior of Internet data sessions. Performance verification of the cross-layer protocols, derived from the dynamic programming conditions, can be achieved by embedding the conditions in a reactive routing protocol for MANETs, in a simulation environment, such as the wireless extension of ns-2. A canonical MANET scenario consists of a distributed collection of battery-powered laptops or hand-held terminals, capable of hosting multimedia applications. Simulation details and performance tradeoffs, not presented, remain for a sequel to the paper.
Hazards of New Media: Youth’s Exposure to Tobacco Ads/Promotions
2014-01-01
Background: A gap in knowledge exists about the youth’s exposure to protobacco campaigns via new electronic media outlets. In response, we use national data to delineate the associations between tobacco ads/promotions delivered through new media outlets (i.e., social network sites and text messages) and youth attitudes/beliefs about tobacco and intent to use (among youth who had not yet used tobacco). Methods: Data were derived from the 2011 National Youth Tobacco Survey, a nationally representative sample of U.S. youth enrolled in both public and private schools (N = 15,673). Logistic regression models were used to examine associations between demographic characteristics and reported exposure to tobacco ads/promotions via social networking sites and text messages. Logistic regression models were also used to investigate associations between exposure tobacco ads/promotions and attitudes toward tobacco. Results: We found that highly susceptible youth (i.e., minorities, very young youth, and youth who have not yet used tobacco) have observed tobacco ads/promotions on social networking sites and text messages. These youth are more likely to have favorable attitudes toward tobacco, including the intention to use tobacco among those who had not yet used tobacco. Conclusions: Our findings underscore the need for policy strategies to more effectively monitor and regulate tobacco advertising via new media outlets. PMID:24163285
Hazards of new media: youth's exposure to tobacco Ads/promotions.
Cavazos-Rehg, Patricia A; Krauss, Melissa J; Spitznagel, Edward L; Grucza, Richard A; Bierut, Laura Jean
2014-04-01
A gap in knowledge exists about the youth's exposure to protobacco campaigns via new electronic media outlets. In response, we use national data to delineate the associations between tobacco ads/promotions delivered through new media outlets (i.e., social network sites and text messages) and youth attitudes/beliefs about tobacco and intent to use (among youth who had not yet used tobacco). Data were derived from the 2011 National Youth Tobacco Survey, a nationally representative sample of U.S. youth enrolled in both public and private schools (N = 15,673). Logistic regression models were used to examine associations between demographic characteristics and reported exposure to tobacco ads/promotions via social networking sites and text messages. Logistic regression models were also used to investigate associations between exposure tobacco ads/promotions and attitudes toward tobacco. We found that highly susceptible youth (i.e., minorities, very young youth, and youth who have not yet used tobacco) have observed tobacco ads/promotions on social networking sites and text messages. These youth are more likely to have favorable attitudes toward tobacco, including the intention to use tobacco among those who had not yet used tobacco. Our findings underscore the need for policy strategies to more effectively monitor and regulate tobacco advertising via new media outlets.
Recall and Effectiveness of Messages Promoting Smoke-Free Policies in Rural Communities.
Rayens, Mary Kay; Butler, Karen M; Wiggins, Amanda T; Kostygina, Ganna; Langley, Ronald E; Hahn, Ellen J
2016-05-01
Low-cost media campaigns increase demand for smoke-free policies in underserved rural areas. The study examined the impact of loss- and gain-framed smoke-free print ads on recall and perceived effectiveness in rural communities, controlling for personal characteristics. Following 6- to 9-month print media campaigns in three rural counties, recall and perceived effectiveness of loss-framed (ie, targeting dangers of secondhand smoke [SHS]) and gain-framed (ie, highlighting positive aspects of smoke-free air) ads were assessed using random-digit-dial phone surveys. Respondents were asked if they remembered each ad, whether they liked it, whether they were prompted to contact a smoke-free coalition, whether the ad made them think, and whether it prompted emotion. Mixed modeling assessed whether personal factors predicted ad recall or perceived effectiveness. Loss-framed ads were less likely to be recalled but more likely to prompt emotion. For ads of both frame types, females reported greater recall and perceived effectiveness than males. Those with less education reported higher perceived effectiveness of the ads but lower recall. Nonsmokers were more likely than smokers to perceive the ads as effective. Knowledge of SHS risk and support for smoke-free workplaces were positively associated with recall and effectiveness. Ad recall and perceived effectiveness were associated with framing and demographic and personal characteristics. Smoke-free efforts in rural areas may be bolstered by continuing to promote benefits of smoke-free workplace policies and educate on SHS risks. Rural areas may need to provide a combination of ad types and framing strategies to appeal to a wide audience. Rural communities are disproportionately affected by SHS and less likely to be protected by smoke-free policies. This study adds evidence-based guidance for tailoring rural smoke-free media campaigns using different framing: gain-framed messages (ie, benefits of smoke-free environments) to promote recall and loss-framed content (ie, dangers of SHS) to prompt emotion. Further, gain-framed messages that are localized to the rural community may be especially effective. Findings support designing smoke-free campaigns in rural communities with the audience in mind by tailoring messages to age, sex, and education level. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Recall and Effectiveness of Messages Promoting Smoke-Free Policies in Rural Communities
Butler, Karen M.; Wiggins, Amanda T.; Kostygina, Ganna; Langley, Ronald E.; Hahn, Ellen J.
2016-01-01
Abstract Introduction: Low-cost media campaigns increase demand for smoke-free policies in underserved rural areas. The study examined the impact of loss- and gain-framed smoke-free print ads on recall and perceived effectiveness in rural communities, controlling for personal characteristics. Methods: Following 6- to 9-month print media campaigns in three rural counties, recall and perceived effectiveness of loss-framed (ie, targeting dangers of secondhand smoke [SHS]) and gain-framed (ie, highlighting positive aspects of smoke-free air) ads were assessed using random-digit-dial phone surveys. Respondents were asked if they remembered each ad, whether they liked it, whether they were prompted to contact a smoke-free coalition, whether the ad made them think, and whether it prompted emotion. Mixed modeling assessed whether personal factors predicted ad recall or perceived effectiveness. Results: Loss-framed ads were less likely to be recalled but more likely to prompt emotion. For ads of both frame types, females reported greater recall and perceived effectiveness than males. Those with less education reported higher perceived effectiveness of the ads but lower recall. Nonsmokers were more likely than smokers to perceive the ads as effective. Knowledge of SHS risk and support for smoke-free workplaces were positively associated with recall and effectiveness. Conclusions: Ad recall and perceived effectiveness were associated with framing and demographic and personal characteristics. Smoke-free efforts in rural areas may be bolstered by continuing to promote benefits of smoke-free workplace policies and educate on SHS risks. Rural areas may need to provide a combination of ad types and framing strategies to appeal to a wide audience. Implications: Rural communities are disproportionately affected by SHS and less likely to be protected by smoke-free policies. This study adds evidence-based guidance for tailoring rural smoke-free media campaigns using different framing: gain-framed messages (ie, benefits of smoke-free environments) to promote recall and loss-framed content (ie, dangers of SHS) to prompt emotion. Further, gain-framed messages that are localized to the rural community may be especially effective. Findings support designing smoke-free campaigns in rural communities with the audience in mind by tailoring messages to age, sex, and education level. PMID:26385925
Cultural variation in antismoking video ads between the United States, Taiwan, and China.
Wong, Tzu-Jung; King, Jessica L; Pomeranz, Jamie L
2016-10-01
Antitobacco advertisement components, including types of messages and advertising appeals, have not been evaluated among multinational groups. This study identified and compared the content of antismoking video ads across three countries. We reviewed 86 antismoking video advertisements for the following information: severity of the consequences of smoking, types of risks, appeals to audiences' self-efficacy, benefits of not smoking, targeted social-ecological level and types of message appeal used. Two researchers independently coded each advertisement with an average inter-coder reliability of 0.79.Analyses showed a variety of focuses: smoking-related health risks (86%), severe consequences of smoking (54.7%), self-efficacy beliefs (40.7%) and benefits of not smoking (84.9%). Compared to the United States and Taiwanese ads, Chinese ads were more likely to target at the community level (10% versus 23.3% versus 47.2%). Additionally, 55% of the United States ads used the fear approach, whereas 61.1% of Chinese ads used the social approach. Taiwanese ads were evenly distributed among both approaches. In conclusion, the countries used different targeting strategies and approaches during message delivery. Although China's neighboring country, Taiwan, has many similar cultural aspects, including the same language, they are greatly influenced by US antitobacco campaigns. As a result, Taiwan's tobacco campaigns appear to have similar components to both China and the United States. Further research is warranted to understand the reasons for each method and to examine the effectiveness of the ads in reducing smoking rates. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Pepper, Jessica K; Emery, Sherry L; Ribisl, Kurt M; Southwell, Brian G; Brewer, Noel T
2014-01-01
Introduction Electronic cigarettes (e-cigarettes) are battery-powered nicotine delivery devices that have become popular among smokers. We conducted an experiment to understand adult smokers’ responses to e-cigarette advertisements and investigate the impact of ads’ arguments and imagery. Methods A US national sample of smokers who had never tried e-cigarettes (n=3253) participated in a between-subjects experiment. Smokers viewed an online advertisement promoting e-cigarettes using one of three comparison types (emphasising similarity to regular cigarettes, differences or neither) with one of three images, for nine conditions total. Smokers then indicated their interest in trying e-cigarettes. Results Ads that emphasised differences between e-cigarettes and regular cigarettes elicited more interest than ads without comparisons (p<0.01), primarily due to claims about e-cigarettes’ lower cost, greater healthfulness and utility for smoking cessation. However, ads that emphasised the similarities of the products did not differ from ads without comparisons. Ads showing a person using an e-cigarette created more interest than ads showing a person without an e-cigarette (p<0.01). Conclusions Interest in trying e-cigarettes was highest after viewing ads with messages about differences between regular and electronic cigarettes and ads showing product use. If e-cigarettes prove to be harmful or ineffective cessation devices, regulators might restrict images of e-cigarette use in advertising, and public health messages should not emphasise differences between regular and electronic cigarettes. To inform additional regulations, future research should seek to identify what advertising messages and features appeal to youth. PMID:24935896
Klimes-Dougan, Bonnie; Wright, Nathan; Klingbeil, David A.
2016-01-01
Suicide continues to be one of the most serious public health challenges. Public service announcements (PSAs) are frequently used to address this challenge, but are rarely sufficiently evaluated to determine if they meet the intended goals, or are associated with potential iatrogenic effects. Although it is challenging to assess the relative impact of different PSA modalities, our group previously noted that one billboard message failed to show the same benefits as one TV ad [e.g., Klimes-Dougan and Lee (1)]. The purpose of this study was to extend these findings to test critical aspects of suicide prevention billboard messaging. Although both simulated billboard messages presented had identical supporting messages, we predicted that the more personal billboard message, focused on saving one’s life, would cause more favorable help-seeking attitudes than the message focused on suicide. Young adult university students (N = 785) were randomly assigned to one of three conditions; one of two billboard simulations or a TV ad simulation. Help-seeking attitudes, maladaptive coping, and reports of concern and distress were evaluated. The results of this study suggest some relative benefits in endorsement of favorable help-seeking attitudes for one of the billboard conditions – stop depression from taking another life. Although further research is needed to determine what methods will alter the risk for suicide in the population, the results of this study provide a useful first step showing that some billboard messaging may favorably influence help-seeking attitudes. PMID:27471477
Klimes-Dougan, Bonnie; Wright, Nathan; Klingbeil, David A
2016-01-01
Suicide continues to be one of the most serious public health challenges. Public service announcements (PSAs) are frequently used to address this challenge, but are rarely sufficiently evaluated to determine if they meet the intended goals, or are associated with potential iatrogenic effects. Although it is challenging to assess the relative impact of different PSA modalities, our group previously noted that one billboard message failed to show the same benefits as one TV ad [e.g., Klimes-Dougan and Lee (1)]. The purpose of this study was to extend these findings to test critical aspects of suicide prevention billboard messaging. Although both simulated billboard messages presented had identical supporting messages, we predicted that the more personal billboard message, focused on saving one's life, would cause more favorable help-seeking attitudes than the message focused on suicide. Young adult university students (N = 785) were randomly assigned to one of three conditions; one of two billboard simulations or a TV ad simulation. Help-seeking attitudes, maladaptive coping, and reports of concern and distress were evaluated. The results of this study suggest some relative benefits in endorsement of favorable help-seeking attitudes for one of the billboard conditions - stop depression from taking another life. Although further research is needed to determine what methods will alter the risk for suicide in the population, the results of this study provide a useful first step showing that some billboard messaging may favorably influence help-seeking attitudes.
76 FR 43987 - Pacific Fishery Management Council; Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-22
... Pacific Fishery Management Council's (Pacific Council) ad hoc groundfish Essential Fish Habitat Review... of groundfish Essential Fish Habitat (EFH). DATES: The work session will be held Thursday, October 6...
Intelligent self-organization methods for wireless ad hoc sensor networks based on limited resources
NASA Astrophysics Data System (ADS)
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 algorithms from flat topologies to two-tier hierarchies of sensor nodes are presented. Results from a few simulations of the proposed algorithms are compared to the published results of other approaches to sensor network self-organization in common scenarios. The estimated network lifetime and extent under static resource allocations are computed.
Pepper, Jessica K; Emery, Sherry L; Ribisl, Kurt M; Southwell, Brian G; Brewer, Noel T
2014-07-01
Electronic cigarettes (e-cigarettes) are battery-powered nicotine delivery devices that have become popular among smokers. We conducted an experiment to understand adult smokers' responses to e-cigarette advertisements and investigate the impact of ads' arguments and imagery. A U.S. national sample of smokers who had never tried e-cigarettes (n=3253) participated in a between-subjects experiment. Smokers viewed an online advertisement promoting e-cigarettes using one of three comparison types (emphasising similarity to regular cigarettes, differences or neither) with one of three images, for nine conditions total. Smokers then indicated their interest in trying e-cigarettes. Ads that emphasised differences between e-cigarettes and regular cigarettes elicited more interest than ads without comparisons (p<0.01), primarily due to claims about e-cigarettes' lower cost, greater healthfulness and utility for smoking cessation. However, ads that emphasised the similarities of the products did not differ from ads without comparisons. Ads showing a person using an e-cigarette created more interest than ads showing a person without an e-cigarette (p<0.01). Interest in trying e-cigarettes was highest after viewing ads with messages about differences between regular and electronic cigarettes and ads showing product use. If e-cigarettes prove to be harmful or ineffective cessation devices, regulators might restrict images of e-cigarette use in advertising, and public health messages should not emphasise differences between regular and electronic cigarettes. To inform additional regulations, future research should seek to identify what advertising messages and features appeal to youth. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Assessing the TARES as an ethical model for antismoking ads.
Lee, Seow Ting; Cheng, I-Huei
2010-01-01
This study examines the ethical dimensions of public health communication, with a focus on antismoking public service announcements (PSAs). The content analysis of 826 television ads from the U.S. Centers for Disease Control and Prevention's (CDC) Media Campaign Resource Center is an empirical testing of Baker and Martinson's (2001) TARES Test that directly examines persuasive messages for truthfulness, authenticity, respect, equity, and social responsibility. In general, the antismoking ads score highly on ethicality. There are significant relationships between ethicality and message attributes (thematic frame, emotion appeal, source, and target audience). Ads that portrayed smoking as damaging to health and socially unacceptable score lower in ethicality than ads that focus on tobacco industry manipulation, addiction, dangers of secondhand smoke, and cessation. Emotion appeals of anger and sadness are associated with higher ethicality than shame and humor appeals. Ads targeting teen/youth audiences score lower on ethicality than ads targeting adult and general audiences. There are significant differences in ethicality based on source; ads produced by the CDC rate higher in ethicality than other sources. Theoretical implications and practical recommendations are discussed.
75 FR 67688 - Pacific Fishery Management Council; Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-03
... Pacific Fishery Management Council's (Council's) Ad Hoc Groundfish Essential Fish Habitat Review Committee... groundfish Essential Fish Habitat (EFH). DATES: The work session will be held Monday, December 20, 2010 from...
Lavack, A M
1999-01-01
This content analysis examines a sample of 203 alcohol-related North American TV commercials dealing with alcohol moderation and driving under the influence (DUI), in order to determine whether the type of ad sponsor has an impact on the message content. Corporate sponsors, such as breweries and distillers, are compared to nonprofit sponsors such as governments and nonprofit organizations. Findings show that ads from corporate sponsors are less likely to make mention of threats or negative consequences, and are also less likely to use fear arousal. However, DUI/alcohol moderation ads from corporate sponsors and nonprofit sponsors do not differ in the degree to which they use humor or positive approaches.
The influence of black carbon on the sorption and desorption of two model PAHs in natural soils.
Chi, Fung-Hwa
2014-01-01
Black carbons (BC) which result from the incomplete combustion of farm waste [man-made (burned) BC] are highly absorbent. In Taiwan, the burning of farm waste known as slash and burn is common. The BCs from the burning may present an environmental challenge. Little is known about the effect of BCs on the transport of hydrophobic organic contaminants (HOC). This study investigates the sorption of anthracene and naphthalene to BCs in soil and efficiency of the surfactants Tween 80 and Triton X-100 in their removal. Both surfactants demonstrated 2-6 times increased solubility in the soils with the addiction of BC. Column experiments were performed to imitate the transportation of these contaminants in groundwater through soils before and after adding BC produced by burning farm waste in the lab. We found significantly increased sorption of anthracene in soil added with BCs produced in the lab, suggesting that fraction of organic carbon (foc) can contribute to sorption of such HOCs. Sorption of naphthalene was increased but not significantly. Comparing the concentrations of contaminants, we found the soil containing BC from burned farm waste absorbed HOC more efficiently than the organic BC (naturally-occurring) in the original soil. Therefore, sorption capacity and influence on the transport of HOC cannot be estimated simply by the foc of the soil because the two BCs differ greatly in their sorption ability. BC from farm waste absorbs more contaminants than naturally occurring BC in the soil.
The Effectiveness of Gateway Communications in Anti-Marijuana Campaigns
YZER, MARCO C.; CAPPELLA, JOSEPH N.; FISHBEIN, MARTIN; HORNIK, ROBERT; AHERN, R. KIRKLAND
2014-01-01
Successful anti-marijuana messages can be hypothesized to have two types of effects, namely persuasion effects, that is, a change in people’s beliefs about using marijuana, and priming effects, that is, a strengthened correlation between beliefs and associated variables such as attitude and intention. This study examined different sets of anti-drug advertisements for persuasion and priming effects. The ads targeted the belief that marijuana is a gateway to stronger drugs, a belief that is often endorsed by campaign planning officials and health educators. A sample of 418 middle and high school students was randomly assigned to a control video or one of three series of ads, two of which included the gateway message in either an explicit or implicit way. Results did not support the use of the gateway belief in anti-marijuana interventions. Whereas no clear persuasion or priming effects were found for any of the ad sequences, there is some possibility that an explicit gateway argument may actually boomerang. In comparison to the control condition, adolescents in the explicit gateway condition tended to agree less with the gateway message and displayed weaker correlations between anti-marijuana beliefs and their attitude toward marijuana use. The results suggest that the gateway message should not be used in anti-drug interventions. PMID:12746037
FHWA White Paper on Mobile Ad Hoc Networks
DOT National Transportation Integrated Search
2018-01-01
Advanced next generation communications technologies offer the potential to greatly improve safety, system efficiency, and mobility across our Nations roadways. These new technologies and processes can address both traditionally difficult as well ...
44 CFR 351.10 - Establishment of committees.
Code of Federal Regulations, 2010 CFR
2010-10-01
... appropriate and on an ad hoc basis, other Federal departments and agencies. In chairing the committee, FEMA... guidance and orientation to other agency members to assist them in carrying out their functions. 1 I...
76 FR 2084 - Pacific Fishery Management Council; Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-12
... Pacific Fishery Management Council's (Council) Ad Hoc Groundfish Process Improvement Committee (PIC) will... the PIC work session is to develop an optimum detailed process and schedule for the 2013-14 groundfish...
American Association of Tissue Banks
... Committees Accreditation American Board of Tissue Banking Bylaws / Ethics Communications Donor Family Services Ad Hoc Committee Education Finance ... Bureau Accredited Bank Search Bookstore Bulletins Global Topics Communications & Media Job Center News Releases Patients and Community Useful ...
NASA Astrophysics Data System (ADS)
Richman, Barbara T.
Motor-assisted sailing ships for ocean research could perform as well as or better than many existing research vessels and could cut fuel consumption by 50-80%, according to a preliminary study by an ad hoc panel of the National Research Council's Ocean Sciences Board (OSB).Rising fuel costs plague ship owners and operators. For example, 2 years ago the U.S. oceanographic fleet had a $6 million overrun in fuel costs. Furthermore, the price of marine diesel fuel skyrocketed from $3 per barrel in 1972 to about $38 per barrel in late 1980. Cutting these costs would be welcome if the savings were not made at the expense of additional crew, longer transit times, or less efficient scientific operations. A sailing ship with auxiliary motor propulsion is a promising prospect, according to the Ad Hoc Panel on the Use of Sailing Ships for Oceanography.
Studying the complex spectral line profiles in the spectra of hot emission stars and quasars .
NASA Astrophysics Data System (ADS)
Danezis, E.; Lyratzi, E.; Antoniou, A.; Popović, L. Č.; Dimitrijević, M. S.
Some Hot Emission Stars and AGNs present peculiar spectral line profiles which are due to DACs and SACs phenomena. The origin and the mechanisms which are responsible for the creation of DACs/SACs is an important problem that has been studied by many researchers. This paper is a review of our efforts to study the origin and the mechanisms of these phenomena. At first we present a theoretic ad hoc picture for the structure of the plasma that surrounds the specific category of hot emission stars that present DACs or SACs. Then we present the mathematical model that we constructed, which is based on the properties of the above ad hoc theoretical structure. Finally, we present some results from our statistical studies that prove the consistency of our model with the classical physical theory.
Ecology Based Decentralized Agent Management System
NASA Technical Reports Server (NTRS)
Peysakhov, Maxim D.; Cicirello, Vincent A.; Regli, William C.
2004-01-01
The problem of maintaining a desired number of mobile agents on a network is not trivial, especially if we want a completely decentralized solution. Decentralized control makes a system more r e bust and less susceptible to partial failures. The problem is exacerbated on wireless ad hoc networks where host mobility can result in significant changes in the network size and topology. In this paper we propose an ecology-inspired approach to the management of the number of agents. The approach associates agents with living organisms and tasks with food. Agents procreate or die based on the abundance of uncompleted tasks (food). We performed a series of experiments investigating properties of such systems and analyzed their stability under various conditions. We concluded that the ecology based metaphor can be successfully applied to the management of agent populations on wireless ad hoc networks.
Implementing MANETS in Android based environment using Wi-Fi direct
NASA Astrophysics Data System (ADS)
Waqas, Muhammad; Babar, Mohammad Inayatullah Khan; Zafar, Mohammad Haseeb
2015-05-01
Packet loss occurs in real-time voice transmission over wireless broadcast Ad-hoc network which creates disruptions in sound. Basic objective of this research is to design a wireless Ad-hoc network based on two Android devices by using the Wireless Fidelity (WIFI) Direct Application Programming Interface (API) and apply the Network Codec, Reed Solomon Code. The network codec is used to encode the data of a music wav file and recover the lost packets if any, packets are dropped using a loss module at the transmitter device to analyze the performance with the objective of retrieving the original file at the receiver device using the network codec. This resulted in faster transmission of the files despite dropped packets. In the end both files had the original formatted music files with complete performance analysis based on the transmission delay.
Worm epidemics in wireless ad hoc networks
NASA Astrophysics Data System (ADS)
Nekovee, Maziar
2007-06-01
A dramatic increase in the number of computing devices with wireless communication capability has resulted in the emergence of a new class of computer worms which specifically target such devices. The most striking feature of these worms is that they do not require Internet connectivity for their propagation but can spread directly from device to device using a short-range radio communication technology, such as WiFi or Bluetooth. In this paper, we develop a new model for epidemic spreading of these worms and investigate their spreading in wireless ad hoc networks via extensive Monte Carlo simulations. Our studies show that the threshold behaviour and dynamics of worm epidemics in these networks are greatly affected by a combination of spatial and temporal correlations which characterize these networks, and are significantly different from the previously studied epidemics in the Internet.
Robotic disaster recovery efforts with ad-hoc deployable cloud computing
NASA Astrophysics Data System (ADS)
Straub, Jeremy; Marsh, Ronald; Mohammad, Atif F.
2013-06-01
Autonomous operations of search and rescue (SaR) robots is an ill posed problem, which is complexified by the dynamic disaster recovery environment. In a typical SaR response scenario, responder robots will require different levels of processing capabilities during various parts of the response effort and will need to utilize multiple algorithms. Placing these capabilities onboard the robot is a mediocre solution that precludes algorithm specific performance optimization and results in mediocre performance. Architecture for an ad-hoc, deployable cloud environment suitable for use in a disaster response scenario is presented. Under this model, each service provider is optimized for the task and maintains a database of situation-relevant information. This service-oriented architecture (SOA 3.0) compliant framework also serves as an example of the efficient use of SOA 3.0 in an actual cloud application.
The dynamical origin of multiple populations in intermediate-age clusters in the Magellanic Clouds
NASA Astrophysics Data System (ADS)
Hong, Jongsuk; de Grijs, Richard; Askar, Abbas; Berczik, Peter; Li, Chengyuan; Wang, Long; Deng, Licai; Kouwenhoven, M. B. N.; Giersz, Mirek; Spurzem, Rainer
2017-11-01
Numerical simulations were carried out to study the origin of multiple stellar populations in the intermediate-age clusters NGC 411 and NGC 1806 in the Magellanic Clouds. We performed NBODY6++ simulations based on two different formation scenarios, an ad hoc formation model where second-generation (SG) stars are formed inside a cluster of first-generation (FG) stars using the gas accumulated from the external intergalactic medium and a minor merger model of unequal mass (MSG/MFG ∼ 5-10 per cent) clusters with an age difference of a few hundred million years. We compared our results such as the radial profile of the SG-to-FG number ratio with observations on the assumption that the SG stars in the observations are composed of cluster members, and confirmed that both the ad hoc formation and merger scenarios reproduce the observed radial trend of the SG-to-FG number ratio, which shows less centrally concentrated SG than FG stars. It is difficult to constrain the formation scenario for the multiple populations by only using the spatial distribution of the SG stars. SG stars originating from the merger scenario show a significant velocity anisotropy and rotational features compared to those from the ad hoc formation scenario. Thus, observations aimed at kinematic properties like velocity anisotropy or rotational velocities for SG stars should be obtained to better understand the formation of the multiple populations in these clusters. This is, however, beyond current instrumentation capabilities.
Choi, Karam; Lee, Jung Chan; Oh, Tae Jung; Kim, Myeungseon; Kim, Hee Chan; Cho, Young Min; Kim, Sungwan
2016-01-01
The results of the isoglycemic intravenous glucose infusion (IIGI) study need to mimic the dynamic glucose profiles during the oral glucose tolerance test (OGTT) to accurately calculate the incretin effect. The glucose infusion rates during IIGI studies have historically been determined by experienced research personnel using the manual ad-hoc method. In this study, a computational method was developed to automatically determine the infusion rates for IIGI study based on a glucose-dynamics model. To evaluate the computational method, 18 subjects with normal glucose tolerance underwent a 75 g OGTT. One-week later, Group 1 (n = 9) and Group 2 (n = 9) underwent IIGI studies using the ad-hoc method and the computational method, respectively. Both methods were evaluated using correlation coefficient, mean absolute relative difference (MARD), and root mean square error (RMSE) between the glucose profiles from the OGTT and the IIGI study. The computational method exhibited significantly higher correlation (0.95 ± 0.03 versus 0.86 ± 0.10, P = 0.019), lower MARD (8.72 ± 1.83% versus 13.11 ± 3.66%, P = 0.002), and lower RMSE (10.33 ± 1.99 mg/dL versus 16.84 ± 4.43 mg/dL, P = 0.002) than the ad-hoc method. The computational method can facilitate IIGI study, and enhance its accuracy and stability. Using this computational method, a high-quality IIGI study can be accomplished without the need for experienced personnel.
[Shared electronic health record in Catalonia, Spain].
Marimon-Suñol, Santiago; Rovira-Barberà, María; Acedo-Anta, Mateo; Nozal-Baldajos, Montserrat A; Guanyabens-Calvet, Joan
2010-02-01
Under the law adopted by its Parliament, the Government of Catalonia has developed an electronic medical record system for its National Health System (NHS). The model is governed by the following principles: 1) The citizen as owner of the data: direct access to his data and right to exercise his opposition's privileges; 2) Generate confidence in the system: security and confidentiality strength; 3) Shared model of information management: publishing system and access to organized and structured information, keeping in mind that the NHS of Catalonia is formally an "Integrated system of healthcare public use" (catalan acronym: SISCAT) with a wide variety of legal structures within its healthcare institutions; 4) Use of communication standards and catalogs as a need for technological and functional integration. In summary: single system of medical records shared between different actors, using interoperability tools and whose development is according to the legislation applicable in Catalonia and within its healthcare system. The result has been the establishment of a set of components and relation rules among which we highlight the following: 1) Display of information that collects sociodemographic data of the citizen, documents or reports (radiology, laboratory, therapeutic procedures, hospital release, emergency room), diagnostic health, prescription and immunization plus a summary screen with the most recent and relevant references; 2) Set of tools helping the user and direct messaging between professionals to facilitate their cooperation; 3) Model designed for supranational connections which will allow adding later, with ad hoc rules, clinical data provided by the private health sector or the proper citizen. 2010 Elsevier España S.L. All rights reserved.
DOT National Transportation Integrated Search
2016-07-01
This report describes two research activities. One research study tested the effects of adding commercial : logos acknowledging sponsorship to Changeable Message Signs. A driving simulator study was conducted : using test signs with travel times and ...
Texture Analysis and Cartographic Feature Extraction.
1985-01-01
Investigations into using various image descriptors as well as developing interactive feature extraction software on the Digital Image Analysis Laboratory...system. Originator-supplied keywords: Ad-Hoc image descriptor; Bayes classifier; Bhattachryya distance; Clustering; Digital Image Analysis Laboratory
Research opportunities in space motion sickness, phase 2
NASA Technical Reports Server (NTRS)
Talbot, J. M.
1983-01-01
Space and motion sickness, the current and projected NASA research program, and the conclusions and suggestions of the ad hoc Working Group are summarized. The frame of reference for the report is ground-based research.
Crowdsourcing innovation at Caltrans.
DOT National Transportation Integrated Search
2016-09-19
This report documents the first year experience in launching and sustaining a web-based, crowdsourcing innovation management tool at the California Department of Transportation (Caltrans). In March 2015 an ad-hoc team of Caltrans managers and staff b...
Fluid Analysis of Network Content Dissemination and Cloud Systems
2017-03-06
orchestration of multiple transfers , within the constraints of the communication substrate. In unstructured or aggressive environments where wireless ad...previous AFOSR/SOARD project, concerns peer-to-peer dissemination in wireless ad-hoc networks. We focus on the necessary tradeoff between an efficient...use of the network substrate, and the necessary reciprocity between peers, aspects that may be in conflict in the wireless setting. Our results
ERIC Educational Resources Information Center
Yang, Stephen J. H.; Chen, Irene Ya-Ling; Shao, Norman W. Y.
2004-01-01
The nature of collaborative learning involves intensive interactions among collaborators, such as articulating knowledge into written, verbal or symbolic forms, authoring articles or posting messages to this community's discussion forum, responding or adding comments to messages or articles posted by others, etc. Knowledge collaborators'…
Global Imagery in Online Advertisements
ERIC Educational Resources Information Center
Hynes, Geraldine E.; Janson, Marius
2007-01-01
A well-designed online advertisement is essential for effective communication with potential customers and contributes to successful e-commerce. However, creating online sales messages that appeal to a broad range of cultures can pose unique challenges. Internet ads must offer both a globally appealing and a culture-specific message that in turn…
Fast incorporation of optical flow into active polygons.
Unal, Gozde; Krim, Hamid; Yezzi, Anthony
2005-06-01
In this paper, we first reconsider, in a different light, the addition of a prediction step to active contour-based visual tracking using an optical flow and clarify the local computation of the latter along the boundaries of continuous active contours with appropriate regularizers. We subsequently detail our contribution of computing an optical flow-based prediction step directly from the parameters of an active polygon, and of exploiting it in object tracking. This is in contrast to an explicitly separate computation of the optical flow and its ad hoc application. It also provides an inherent regularization effect resulting from integrating measurements along polygon edges. As a result, we completely avoid the need of adding ad hoc regularizing terms to the optical flow computations, and the inevitably arbitrary associated weighting parameters. This direct integration of optical flow into the active polygon framework distinguishes this technique from most previous contour-based approaches, where regularization terms are theoretically, as well as practically, essential. The greater robustness and speed due to a reduced number of parameters of this technique are additional and appealing features.
Tsai, Wan-Hsiu Sunny; Lancaster, Alyse R
2012-01-01
This exploratory study applies Taylor's (1999) six-segment message strategy wheel to direct-to-consumer (DTC) pharmaceutical television commercials to understand message strategies adopted by pharmaceutical advertisers to persuade consumers. A convenience sample of 96 DTC commercial campaigns was analyzed. The results suggest that most DTC drug ads used a combination approach, providing consumers with medical and drug information while simultaneously appealing to the viewer's ego-related needs and desires. In contrast to ration and ego strategies, other approaches including routine, acute need, and social are relatively uncommon while sensory was the least common message strategy. Findings thus recognized the educational value of DTC commercials.
Bundles of Norms About Teen Sex and Pregnancy.
Mollborn, Stefanie; Sennott, Christie
2015-09-01
Teen pregnancy is a cultural battleground in struggles over morality, education, and family. At its heart are norms about teen sex, contraception, pregnancy, and abortion. Analyzing 57 interviews with college students, we found that "bundles" of related norms shaped the messages teens hear. Teens did not think their communities encouraged teen sex or pregnancy, but normative messages differed greatly, with either moral or practical rationalizations. Teens readily identified multiple norms intended to regulate teen sex, contraception, abortion, childbearing, and the sanctioning of teen parents. Beyond influencing teens' behavior, norms shaped teenagers' public portrayals and post hoc justifications of their behavior. Although norm bundles are complex to measure, participants could summarize them succinctly. These bundles and their conflicting behavioral prescriptions create space for human agency in negotiating normative pressures. The norm bundles concept has implications for teen pregnancy prevention policies and can help revitalize social norms for understanding health behaviors. © The Author(s) 2014.
Taming Wild Horses: The Need for Virtual Time-based Scheduling of VMs in Network Simulations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yoginath, Srikanth B; Perumalla, Kalyan S; Henz, Brian J
2012-01-01
The next generation of scalable network simulators employ virtual machines (VMs) to act as high-fidelity models of traffic producer/consumer nodes in simulated networks. However, network simulations could be inaccurate if VMs are not scheduled according to virtual time, especially when many VMs are hosted per simulator core in a multi-core simulator environment. Since VMs are by default free-running, on the outset, it is not clear if, and to what extent, their untamed execution affects the results in simulated scenarios. Here, we provide the first quantitative basis for establishing the need for generalized virtual time scheduling of VMs in network simulators,more » based on an actual prototyped implementations. To exercise breadth, our system is tested with multiple disparate applications: (a) a set of message passing parallel programs, (b) a computer worm propagation phenomenon, and (c) a mobile ad-hoc wireless network simulation. We define and use error metrics and benchmarks in scaled tests to empirically report the poor match of traditional, fairness-based VM scheduling to VM-based network simulation, and also clearly show the better performance of our simulation-specific scheduler, with up to 64 VMs hosted on a 12-core simulator node.« less
3D video coding: an overview of present and upcoming standards
NASA Astrophysics Data System (ADS)
Merkle, Philipp; Müller, Karsten; Wiegand, Thomas
2010-07-01
An overview of existing and upcoming 3D video coding standards is given. Various different 3D video formats are available, each with individual pros and cons. The 3D video formats can be separated into two classes: video-only formats (such as stereo and multiview video) and depth-enhanced formats (such as video plus depth and multiview video plus depth). Since all these formats exist of at least two video sequences and possibly additional depth data, efficient compression is essential for the success of 3D video applications and technologies. For the video-only formats the H.264 family of coding standards already provides efficient and widely established compression algorithms: H.264/AVC simulcast, H.264/AVC stereo SEI message, and H.264/MVC. For the depth-enhanced formats standardized coding algorithms are currently being developed. New and specially adapted coding approaches are necessary, as the depth or disparity information included in these formats has significantly different characteristics than video and is not displayed directly, but used for rendering. Motivated by evolving market needs, MPEG has started an activity to develop a generic 3D video standard within the 3DVC ad-hoc group. Key features of the standard are efficient and flexible compression of depth-enhanced 3D video representations and decoupling of content creation and display requirements.
Critical review of expert system validation in transportation
DOT National Transportation Integrated Search
1997-01-01
Expert system validationthat is, testing systems to ascertain whether they achieve acceptable performance levelshas with few exceptions been ad hoc, informal, and of dubious value. Very few efforts have been made in this regard in the transport...
Effectiveness of AODV Protocol under Hidden Node Environment
NASA Astrophysics Data System (ADS)
Garg, Ruchi; Sharma, Himanshu; Kumar, Sumit
IEEE 802.11 is a standard for mobile ad hoc networks (MANET), implemented with various different protocols. Ad Hoc on Demand Distance Vector Routing (AODV) is one of the several protocols of IEEE 802.11, intended to provide various Quality of Service (QOS) parameters under acceptable range. To avoid the collision and interference the MAC protocol has only two solutions, one, to sense the physical carrier and second, to use the RTS/CTS handshake mechanism. But with the help of these methods AODV is not free from the problem of hidden nodes like other several protocols. Under the hidden node environment, performance of AODV depends upon various factors. The position of receiver and sender among the other nodes is very crucial and it affects the performance. Under the various situations the AODV is simulated with the help of NS2 and the outcomes are discussed.
Efficient Proximity Computation Techniques Using ZIP Code Data for Smart Cities †
Murdani, Muhammad Harist; Hong, Bonghee
2018-01-01
In this paper, we are interested in computing ZIP code proximity from two perspectives, proximity between two ZIP codes (Ad-Hoc) and neighborhood proximity (Top-K). Such a computation can be used for ZIP code-based target marketing as one of the smart city applications. A naïve approach to this computation is the usage of the distance between ZIP codes. We redefine a distance metric combining the centroid distance with the intersecting road network between ZIP codes by using a weighted sum method. Furthermore, we prove that the results of our combined approach conform to the characteristics of distance measurement. We have proposed a general and heuristic approach for computing Ad-Hoc proximity, while for computing Top-K proximity, we have proposed a general approach only. Our experimental results indicate that our approaches are verifiable and effective in reducing the execution time and search space. PMID:29587366
Noise-Assisted Concurrent Multipath Traffic Distribution in Ad Hoc Networks
Murata, Masayuki
2013-01-01
The concept of biologically inspired networking has been introduced to tackle unpredictable and unstable situations in computer networks, especially in wireless ad hoc networks where network conditions are continuously changing, resulting in the need of robustness and adaptability of control methods. Unfortunately, existing methods often rely heavily on the detailed knowledge of each network component and the preconfigured, that is, fine-tuned, parameters. In this paper, we utilize a new concept, called attractor perturbation (AP), which enables controlling the network performance using only end-to-end information. Based on AP, we propose a concurrent multipath traffic distribution method, which aims at lowering the average end-to-end delay by only adjusting the transmission rate on each path. We demonstrate through simulations that, by utilizing the attractor perturbation relationship, the proposed method achieves a lower average end-to-end delay compared to other methods which do not take fluctuations into account. PMID:24319375
Assessment of the 802.11g Wireless Protocol for Lunar Surface Communications
NASA Technical Reports Server (NTRS)
Chelmins, David T.; Bguyen, Hung D.; Foore, Lawrence R.
2009-01-01
Future lunar surface missions supporting the NASA Vision for Space Exploration will rely on wireless networks to transmit voice and data. The ad hoc network architecture is of particular interest since it does not require a complex infrastructure. In this report, we looked at data performance over an ad hoc network with varying distances between Apple AirPort wireless cards. We developed a testing program to transmit data packets at precise times and then monitored the receive time to characterize connection delay, packet loss, and data rate. Best results were received for wireless links of less than 75 ft, and marginally acceptable (25-percent) packet loss was received at 150 ft. It is likely that better results will be obtained on the lunar surface because of reduced radiofrequency interference; however, higher power transmitters or receivers will be needed for significant performance gains.
Impact of Beamforming on the Path Connectivity in Cognitive Radio Ad Hoc Networks
Dung, Le The; Hieu, Tran Dinh; Choi, Seong-Gon; Kim, Byung-Seo; An, Beongku
2017-01-01
This paper investigates the impact of using directional antennas and beamforming schemes on the connectivity of cognitive radio ad hoc networks (CRAHNs). Specifically, considering that secondary users use two kinds of directional antennas, i.e., uniform linear array (ULA) and uniform circular array (UCA) antennas, and two different beamforming schemes, i.e., randomized beamforming and center-directed to communicate with each other, we study the connectivity of all combination pairs of directional antennas and beamforming schemes and compare their performances to those of omnidirectional antennas. The results obtained in this paper show that, compared with omnidirectional transmission, beamforming transmission only benefits the connectivity when the density of secondary user is moderate. Moreover, the combination of UCA and randomized beamforming scheme gives the highest path connectivity in all evaluating scenarios. Finally, the number of antenna elements and degree of path loss greatly affect path connectivity in CRAHNs. PMID:28346377
Ad hoc committee on global climate issues: Annual report
Gerhard, L.C.; Hanson, B.M.B.
2000-01-01
The AAPG Ad Hoc Committee on Global Climate Issues has studied the supposition of human-induced climate change since the committee's inception in January 1998. This paper details the progress and findings of the committee through June 1999. At that time there had been essentially no geologic input into the global climate change debate. The following statements reflect the current state of climate knowledge from the geologic perspective as interpreted by the majority of the committee membership. The committee recognizes that new data could change its conclusions. The earth's climate is constantly changing owing to natural variability in earth processes. Natural climate variability over recent geological time is greater than reasonable estimates of potential human-induced greenhouse gas changes. Because no tool is available to test the supposition of human-induced climate change and the range of natural variability is so great, there is no discernible human influence on global climate at this time.
An advanced search engine for patent analytics in medicinal chemistry.
Pasche, Emilie; Gobeill, Julien; Teodoro, Douglas; Gaudinat, Arnaud; Vishnykova, Dina; Lovis, Christian; Ruch, Patrick
2012-01-01
Patent collections contain an important amount of medical-related knowledge, but existing tools were reported to lack of useful functionalities. We present here the development of TWINC, an advanced search engine dedicated to patent retrieval in the domain of health and life sciences. Our tool embeds two search modes: an ad hoc search to retrieve relevant patents given a short query and a related patent search to retrieve similar patents given a patent. Both search modes rely on tuning experiments performed during several patent retrieval competitions. Moreover, TWINC is enhanced with interactive modules, such as chemical query expansion, which is of prior importance to cope with various ways of naming biomedical entities. While the related patent search showed promising performances, the ad-hoc search resulted in fairly contrasted results. Nonetheless, TWINC performed well during the Chemathlon task of the PatOlympics competition and experts appreciated its usability.
A User Authentication Scheme Based on Elliptic Curves Cryptography for Wireless Ad Hoc Networks
Chen, Huifang; Ge, Linlin; Xie, Lei
2015-01-01
The feature of non-infrastructure support in a wireless ad hoc network (WANET) makes it suffer from various attacks. Moreover, user authentication is the first safety barrier in a network. A mutual trust is achieved by a protocol which enables communicating parties to authenticate each other at the same time and to exchange session keys. For the resource-constrained WANET, an efficient and lightweight user authentication scheme is necessary. In this paper, we propose a user authentication scheme based on the self-certified public key system and elliptic curves cryptography for a WANET. Using the proposed scheme, an efficient two-way user authentication and secure session key agreement can be achieved. Security analysis shows that our proposed scheme is resilient to common known attacks. In addition, the performance analysis shows that our proposed scheme performs similar or better compared with some existing user authentication schemes. PMID:26184224
A User Authentication Scheme Based on Elliptic Curves Cryptography for Wireless Ad Hoc Networks.
Chen, Huifang; Ge, Linlin; Xie, Lei
2015-07-14
The feature of non-infrastructure support in a wireless ad hoc network (WANET) makes it suffer from various attacks. Moreover, user authentication is the first safety barrier in a network. A mutual trust is achieved by a protocol which enables communicating parties to authenticate each other at the same time and to exchange session keys. For the resource-constrained WANET, an efficient and lightweight user authentication scheme is necessary. In this paper, we propose a user authentication scheme based on the self-certified public key system and elliptic curves cryptography for a WANET. Using the proposed scheme, an efficient two-way user authentication and secure session key agreement can be achieved. Security analysis shows that our proposed scheme is resilient to common known attacks. In addition, the performance analysis shows that our proposed scheme performs similar or better compared with some existing user authentication schemes.
Is heart transplantation after circulatory death compatible with the dead donor rule?
Nair-Collins, Michael; Miller, Franklin G
2016-05-01
Dalle Ave et al (2016) provide a valuable overview of several protocols for heart transplantation after circulatory death. However, their analysis of the compatibility of heart donation after circulatory death (DCD) with the dead donor rule (DDR) is flawed. Their permanence-based criteria for death, which depart substantially from established law and bioethics, are ad hoc and unfounded. Furthermore, their analysis is self-defeating, because it undercuts the central motivation for DDR as both a legal and a moral constraint, rendering the DDR vacuous and trivial. Rather than devise new and ad hoc criteria for death for the purpose of rendering DCD nominally consistent with DDR, we contend that the best approach is to explicitly abandon DDR. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
NASA Technical Reports Server (NTRS)
1985-01-01
In 1984 the ad hoc committee on Space Station Engineering and Technology Development of the Aeronautics and Space Engineering Board (ASEB) conducted a review of the National Aeronautics and Space Administration's (NASA's) space station program planning. The review addressed the initial operating configuration (IOC) of the station. The ASEB has reconstituted the ad hoc committee which then established panels to address each specific related subject. The participants of the panels come from the committee, industry, and universities. The proceedings of the Panel on In Space Engineering Research and Technology Development are presented in this report. Activities, and plans for identifying and developing R&T programs to be conducted by the space station and related in space support needs including module requirements are addressed. Consideration is given to use of the station for R&T for other government agencies, universities, and industry.
Some new ideas for the study of the complex spectral line profiles of hot emission stars and quasars
NASA Astrophysics Data System (ADS)
Danezis, E.
2013-01-01
Some Hot Emission Stars and AGNs present peculiar spectral line profiles which are due to DACs and SACs phenomena. The origin and the mechanisms which are responsible for the creation of DACs/SACs is an important problem that has been studied by many researchers. This paper is a review of our efforts to study the origin and the mechanisms of these phenomena. At first we present a theoretic ad hoc picture for the structure of the plasma that surrounds the specific category of hot emission stars that present DACs or SACs. Then we present the mathematical model that we constructed, which is based on the properties of the above ad hoc theoretical structure. Finally, we present some results from our statistical studies that prove the consistency of our model with the classical physical theory.
Software Architecture of Sensor Data Distribution In Planetary Exploration
NASA Technical Reports Server (NTRS)
Lee, Charles; Alena, Richard; Stone, Thom; Ossenfort, John; Walker, Ed; Notario, Hugo
2006-01-01
Data from mobile and stationary sensors will be vital in planetary surface exploration. The distribution and collection of sensor data in an ad-hoc wireless network presents a challenge. Irregular terrain, mobile nodes, new associations with access points and repeaters with stronger signals as the network reconfigures to adapt to new conditions, signal fade and hardware failures can cause: a) Data errors; b) Out of sequence packets; c) Duplicate packets; and d) Drop out periods (when node is not connected). To mitigate the effects of these impairments, a robust and reliable software architecture must be implemented. This architecture must also be tolerant of communications outages. This paper describes such a robust and reliable software infrastructure that meets the challenges of a distributed ad hoc network in a difficult environment and presents the results of actual field experiments testing the principles and actual code developed.
NASA Astrophysics Data System (ADS)
Jenkinson, Dylan; Leung, Kai-Cheung; Trotman, Andrew
The University of Otago submitted three element runs and three passage runs to the Relevance-in-Context task of the ad hoc track. The best Otago run was a whole-document run placing 7th. The best Otago passage run placed 13th while the best Otago element run placed 31st. There were a total of 40 runs submitted to the task. The ad hoc result reinforced our prior belief that passages are better answers than elements and that the most important aspect of the focused retrieval is the identification of relevant documents. Six runs were submitted to the Link-the-Wiki track. The best Otago run placed 1st (of 21) in file to file automatic assessment and 6th (of 28) with manual assessment. The Itakura & Clarke algorithm was used for outgoing links, with special attention paid to parsing and case sensitivity. For incoming links representative terms were selected from the document and used to find similar documents.
A critical examination of community-based responses to household food insecurity in Canada.
Tarasuk, V
2001-08-01
Over the past two decades, household food insecurity has emerged as a significant social problem and serious public health concern in the "First World." In Canada, communities initially responded by establishing ad hoc charitable food assistance programs, but the programs have become institutionalized. In the quest for more appropriate and effective responses, a variety of community development programs have recently been initiated. Some are designed to foster personal empowerment through self-help and mutual support; others promote community-level strategies to strengthen local control over food production. The capacity of current initiatives to improve household food security appears limited by their inability to overcome or alter the poverty that under-pins this problem. This may relate to the continued focus on food-based responses, the ad hoc and community-based nature of the initiatives, and their origins in publicly funded health and social service sectors.
Real-Time Support on IEEE 802.11 Wireless Ad-Hoc Networks: Reality vs. Theory
NASA Astrophysics Data System (ADS)
Kang, Mikyung; Kang, Dong-In; Suh, Jinwoo
The usable throughput of an IEEE 802.11 system for an application is much less than the raw bandwidth. Although 802.11b has a theoretical maximum of 11Mbps, more than half of the bandwidth is consumed by overhead leaving at most 5Mbps of usable bandwidth. Considering this characteristic, this paper proposes and analyzes a real-time distributed scheduling scheme based on the existing IEEE 802.11 wireless ad-hoc networks, using USC/ISI's Power Aware Sensing Tracking and Analysis (PASTA) hardware platform. We compared the distributed real-time scheduling scheme with the real-time polling scheme to meet deadline, and compared a measured real bandwidth with a theoretical result. The theoretical and experimental results show that the distributed scheduling scheme can guarantee real-time traffic and enhances the performance up to 74% compared with polling scheme.
Context dependent off loading for cloudlet in mobile ad-hoc network
NASA Astrophysics Data System (ADS)
Bhatt, N.; Nadesh, R. K.; ArivuSelvan, K.
2017-11-01
Cloud Computing in Mobile Ad-hoc network is emerging part of research consideration as the demand and competency of mobile devices increased in last few years. To follow out operation within the remote cloud builds the postponement and influences the administration standard. To keep away from this trouble cloudlet is presented. Cloudlet gives identical support of the devices as cloud at low inactivity however at high transfer speed. Be that as it may, choice of a cloudlet for offloading calculation with flat energy is a noteworthy test if multiple cloud let is accessible adjacent. Here I proposed energy and bandwidth (Traffic overload for communication with cloud) aware cloudlet selection strategy based on the context dependency of the device location. It works on the basis of mobile device location and bandwidth availability of cloudlet. The cloudlet offloading and selection process using given solution is simulated in Cloud ~ Simulator.
Efficient Proximity Computation Techniques Using ZIP Code Data for Smart Cities †.
Murdani, Muhammad Harist; Kwon, Joonho; Choi, Yoon-Ho; Hong, Bonghee
2018-03-24
In this paper, we are interested in computing ZIP code proximity from two perspectives, proximity between two ZIP codes ( Ad-Hoc ) and neighborhood proximity ( Top-K ). Such a computation can be used for ZIP code-based target marketing as one of the smart city applications. A naïve approach to this computation is the usage of the distance between ZIP codes. We redefine a distance metric combining the centroid distance with the intersecting road network between ZIP codes by using a weighted sum method. Furthermore, we prove that the results of our combined approach conform to the characteristics of distance measurement. We have proposed a general and heuristic approach for computing Ad-Hoc proximity, while for computing Top-K proximity, we have proposed a general approach only. Our experimental results indicate that our approaches are verifiable and effective in reducing the execution time and search space.
An epidemic model for biological data fusion in ad hoc sensor networks
NASA Astrophysics Data System (ADS)
Chang, K. C.; Kotari, Vikas
2009-05-01
Bio terrorism can be a very refined and a catastrophic approach of attacking a nation. This requires the development of a complete architecture dedicatedly designed for this purpose which includes but is not limited to Sensing/Detection, Tracking and Fusion, Communication, and others. In this paper we focus on one such architecture and evaluate its performance. Various sensors for this specific purpose have been studied. The accent has been on use of Distributed systems such as ad-hoc networks and on application of epidemic data fusion algorithms to better manage the bio threat data. The emphasis has been on understanding the performance characteristics of these algorithms under diversified real time scenarios which are implemented through extensive JAVA based simulations. Through comparative studies on communication and fusion the performance of channel filter algorithm for the purpose of biological sensor data fusion are validated.
Dixon, Helen; Scully, Maree; Durkin, Sarah; Brennan, Emily; Cotter, Trish; Maloney, Sarah; O'Hara, Blythe J; Wakefield, Melanie
2015-08-20
Mass media communications are an important component of comprehensive interventions to address population levels of overweight and obesity, yet we have little understanding of the effective characteristics of specific advertisements (ads) on this topic. This study aimed to quantitatively test audience reactions to existing adult-focused public health television ads addressing overweight and obesity to determine which ads have the highest levels of message acceptance, argument strength, personalised perceived effectiveness and negative emotional impact. 1116 Australian adults aged 21-55 years recruited from a national online panel participated in this web-based study. Quotas were applied to achieve even numbers of males and females, those aged 21-29 years and 30-55 years, and those with a healthy weight (BMI = 18.5-24.9) and overweight/obesity (BMI = 25+). Participants were randomly assigned to view and rate four of eight ads that varied in terms of message content (health consequences, supportive/encouraging or social norms/acceptability) and execution style (graphic, simulation/animation, positive or negative testimonial, or depicted scene). Toxic fat (a graphic, health consequences ad) was the top performing ad on all four outcome measures and was significantly more likely than the other ads tested to promote strong responses in terms of message acceptance, argument strength and negative emotional impact. Measure up (a negative testimonial, health consequences ad) performed comparably on personalised perceived effectiveness. Most ads produced stronger perceptions of personalised perceived effectiveness among participants with overweight/obesity compared to participants with healthy weight. Some ads were more likely to promote strong negative emotions among participants with overweight/obesity. Findings provide preliminary evidence of the most promising content and executional styles of ads that could be pursued as part of obesity prevention campaigns. Ads emphasising the negative health consequences of excess weight appear to elicit stronger cognitive and emotional responses from adults with overweight/obesity. However, careful pre-testing of these types of ads is needed prior to their inclusion in actual campaigns to ensure they do not have unintended negative impacts such as increased stigmatisation of vulnerable individuals and increased levels of body dissatisfaction and/or eating-disordered behaviour among at-risk population sub-groups.
Sirriyeh, Reema; Lawton, Rebecca; Ward, Jane
2010-11-01
The present study attempts to develop and pilot the feasibility and efficacy of a novel intervention using affective messages as a strategy to increase physical activity (PA) levels in adolescents. Design An exploratory pilot randomized control trial was used to compare behaviour change over 2 weeks. A modified form of the International Physical Activity Questionnaire was used to assess PA behaviour. A total of 120 adolescents (16-19 years) from 4 sixth forms in West Yorkshire completed the field-based study. Participants were randomly assigned to one of three experimental conditions, or the control condition (N=28). Participants in experimental conditions received 1 short messaging service (SMS) text message per day over the 2 weeks, which included manipulations of either affective beliefs (enjoyable/unenjoyable; N=31), instrumental beliefs (beneficial/harmful; N=30), or a combination of these (N=31). Control participants received one SMS text message per week. Outcomes were measured at baseline and at the end of the 2 week intervention. PA levels increased by the equivalent of 31.5 minutes of moderate (four metabolic equivalent) activity per week during the study. Main effects of condition (p=.049), and current physical activity level (p=.002) were identified, along with a significant interaction between condition and current activity level (p=.006). However, when the sample was split at baseline into active and inactive participants, a main effect of condition remained for inactive participants only (p=.001). Post hoc analysis revealed that inactive participants who received messages targeting affective beliefs increased their activity levels significantly more than the instrumental (p=.012), combined (p=.002), and control groups (p=.018). Strategies based on affective associations may be more effective for increasing PA levels in inactive individuals.
A study on the development of public campaign messages for organ donation promotion in Korea.
Sun, Hye-Jin
2015-12-01
This study aims to find an effective method of expressing a message in public service ads by investigating whether or not a message framing type affects the outcome. Specifically, the study looks into the effects of messaging on organ donation by identifying how the type of message framing (positive vs. negative) and appeal type (rational vs. emotional) affect the attitude and behavioural intention of the consumer. The individual characteristics of each subject such as altruistic mind, level of self-monitoring and issue involvement were selected as intermediate variables that may affect the impact of a message. The study therefore tries to establish a proposition that can be used to generate an effective promotional message on organ donation in a systematic way. © The Author (2014). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Making great leaps forward: Accounting for detectability in herpetological field studies
Mazerolle, Marc J.; Bailey, Larissa L.; Kendall, William L.; Royle, J. Andrew; Converse, Sarah J.; Nichols, James D.
2007-01-01
Detecting individuals of amphibian and reptile species can be a daunting task. Detection can be hindered by various factors such as cryptic behavior, color patterns, or observer experience. These factors complicate the estimation of state variables of interest (e.g., abundance, occupancy, species richness) as well as the vital rates that induce changes in these state variables (e.g., survival probabilities for abundance; extinction probabilities for occupancy). Although ad hoc methods (e.g., counts uncorrected for detection, return rates) typically perform poorly in the face of no detection, they continue to be used extensively in various fields, including herpetology. However, formal approaches that estimate and account for the probability of detection, such as capture-mark-recapture (CMR) methods and distance sampling, are available. In this paper, we present classical approaches and recent advances in methods accounting for detectability that are particularly pertinent for herpetological data sets. Through examples, we illustrate the use of several methods, discuss their performance compared to that of ad hoc methods, and we suggest available software to perform these analyses. The methods we discuss control for imperfect detection and reduce bias in estimates of demographic parameters such as population size, survival, or, at other levels of biological organization, species occurrence. Among these methods, recently developed approaches that no longer require marked or resighted individuals should be particularly of interest to field herpetologists. We hope that our effort will encourage practitioners to implement some of the estimation methods presented herein instead of relying on ad hoc methods that make more limiting assumptions.
Predicting impact of multi-paths on phase change in map-based vehicular ad hoc networks
NASA Astrophysics Data System (ADS)
Rahmes, Mark; Lemieux, George; Sonnenberg, Jerome; Chester, David B.
2014-05-01
Dynamic Spectrum Access, which through its ability to adapt the operating frequency of a radio, is widely believed to be a solution to the limited spectrum problem. 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 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, secondary users opportunistically attempt to radiate at a specific frequency when the primary user is not using it. We quantify optimal signal detection in map based cognitive radio networks with multiple rapidly varying phase changes and multiple orthogonal signals. Doppler shift occurs due to reflection, scattering, and rapid vehicle movement. Path propagation as well as vehicle movement produces either constructive or destructive interference with the incident wave. Our signal detection algorithms can assist the Doppler spread compensation algorithm by deciding how many phase changes in signals are present in a selected band of interest. Additionally we can populate a spatial radio environment map (REM) database with known information that can be leveraged in an ad hoc network to facilitate Dynamic Spectrum Access. We show how topography can help predict the impact of multi-paths on phase change, as well as about the prediction from dense traffic areas. Utilization of high resolution geospatial data layers in RF propagation analysis is directly applicable.
Mularski, Richard A; Reinke, Lynn F; Carrieri-Kohlman, Virginia; Fischer, Mark D; Campbell, Margaret L; Rocker, Graeme; Schneidman, Ann; Jacobs, Susan S; Arnold, Robert; Benditt, Joshua O; Booth, Sara; Byock, Ira; Chan, Garrett K; Curtis, J Randall; Donesky, Doranne; Hansen-Flaschen, John; Heffner, John; Klein, Russell; Limberg, Trina M; Manning, Harold L; Morrison, R Sean; Ries, Andrew L; Schmidt, Gregory A; Selecky, Paul A; Truog, Robert D; Wang, Angela C C; White, Douglas B
2013-10-01
In 2009, the American Thoracic Society (ATS) funded an assembly project, Palliative Management of Dyspnea Crisis, to focus on identification, management, and optimal resource utilization for effective palliation of acute episodes of dyspnea. We conducted a comprehensive search of the medical literature and evaluated available evidence from systematic evidence-based reviews (SEBRs) using a modified AMSTAR approach and then summarized the palliative management knowledge base for participants to use in discourse at a 2009 ATS workshop. We used an informal consensus process to develop a working definition of this novel entity and established an Ad Hoc Committee on Palliative Management of Dyspnea Crisis to further develop an official ATS document on the topic. The Ad Hoc Committee members defined dyspnea crisis as "sustained and severe resting breathing discomfort that occurs in patients with advanced, often life-limiting illness and overwhelms the patient and caregivers' ability to achieve symptom relief." Dyspnea crisis can occur suddenly and is characteristically without a reversible etiology. The workshop participants focused on dyspnea crisis management for patients in whom the goals of care are focused on palliation and for whom endotracheal intubation and mechanical ventilation are not consistent with articulated preferences. However, approaches to dyspnea crisis may also be appropriate for patients electing life-sustaining treatment. The Ad Hoc Committee developed a Workshop Report concerning assessment of dyspnea crisis; ethical and professional considerations; efficient utilization, communication, and care coordination; clinical management of dyspnea crisis; development of patient education and provider aid products; and enhancing implementation with audit and quality improvement.
Boarding Team Networking on the Move: Applying Unattended Relay Nodes
2014-09-01
below the main deck via a wireless ad-hoc network will enhance the situational awareness. Regarding the boarding of a non-compliant vessel, tracking...reaction time. 14. SUBJECT TERMS Maritime Interdiction Operations, Boarding Team Networking , Unattended Relay Nodes, Wireless Mesh Networks Onboard...the steel structures of naval vessels obstruct signals to propagate below the main deck. Extending the network below the main deck via a wireless ad
AD Hoc Study on Human Robot Interface Issues
2002-09-01
of joint range of motion limits on strength. When the angle of a fully deflected aircraft rudder/ brake pedal is beyond the limit of ankle...mobility, the pedal will seem to have excessive resistance. In addition, this will prevent the pilot from fully utilizing the brakes of the aircraft...importance and value added of HE efforts. 34 Center High-Mounted Brake Lights. In 1985, after extensive HE studies showing positive
Mathematics, Information, and Life Sciences
2012-03-05
INS • Chip -scale atomic clocks • Ad hoc networks • Polymorphic networks • Agile networks • Laser communications • Frequency-agile RF systems...FY12 BAA Bionavigation (Bio) Neuromorphic Computing (Human) Multi-scale Modeling (Math) Foundations of Information Systems (Info) BRI
Overview of a Crash Energy Management Specification for Passenger Rail Equipment
DOT National Transportation Integrated Search
2007-04-04
At the request of METROLINK, the Federal Railroad : Administration (FRA), with the Federal Transit Administration and the : American Public Transportation Association, formed the ad hoc Crash : Energy Management Working Group in May 2005. This group ...
Magnetic Mars Dust Removal Technology
NASA Astrophysics Data System (ADS)
Arias, F. J.; De las Heras, S. A.
2018-04-01
From the recorded data from recent Mars missions, there are substantial evidence that the dust of Mars is strongly magnetic. In this work we propose a novel, reliable, robust, and ad hoc technique for Mars dust removal for Mars Sample Return mission.
Schultz, Douglas S; Brabender, Virginia M
2013-01-01
To determine the effects of reading the Wikipedia article on the Rorschach on Comprehensive System variables, participants in this study (recruited from parent-teacher associations, online message boards, and graduate schools; N = 50) were provided with either a copy of the Wikipedia article on the Rorschach (from April 2010) or an irrelevant article, then administered the Rorschach and instructed to "fake good." Monetary incentives were used to increase motivation to dissimulate. Initial results indicated that participants given the Wikipedia article produced a lower number of responses (R) and had higher scores on Populars, X+%, XA%, and WDA% as compared to controls. However, post-hoc analyses revealed that when the influence of Populars was controlled, significant differences for X+%, XA%, and WDA% disappeared. No significant differences were found for Form%, Zf, Blends, or PER, although post-hoc analyses controlling for differences in R revealed a significant difference between groups on Zf%. Limitations of the study and implications for clinical and forensic practice are discussed.
NASA Astrophysics Data System (ADS)
Kopeć, J. M.; Kwiatkowski, K.; de Haan, S.; Malinowski, S. P.
2015-11-01
Navigational information broadcast by commercial aircraft in the form of Mode-S and ADS-B messages can be considered a new and valid source of upper air turbulence measurements. A set of three processing methods is proposed and analysed using a quality record of turbulence encounters made by a research aircraft. The proposed methods are based on processing the vertical acceleration or the background wind into the eddy dissipation rate. All the necessary parameters are conveyed in the Mode-S/ADS-B messages. The comparison of the results of application of the processing against a reference eddy dissipation rate obtained using on-board accelerometer indicate a significant potential of those methods. The advantages and limitation of the presented approaches are discussed.
Which types of anti-smoking television advertisements work better in Taiwan?
Huang, Li-Ling; Friedman, Daniela B; Lin, Feng-Chang; Thrasher, James F
2018-06-01
Research in high income countries suggests that anti-smoking television advertisements with emotionally evocative graphic messages or personal testimonials that depict serious consequences from smoking are the most effective. Research to determine the most effective smoking cessation messages for low- and middle-income countries is needed to inform campaign development in these countries. Fifty-four male Taiwanese smokers, aged 18-34, rated advertisements and participated in a focus group to evaluate eight antismoking television advertisements with contrasting messaging strategies. Participants individually evaluated advertisements, after which they participated in a semi-structured focus group discussion (10 groups, 2-9 smokers per group). One week after this session, participants were called to assess advertisement recall. Both quantitative and qualitative data indicated that highly emotional testimonial ads that featured a graphic portrayal of personal suffering from the consequences of smoking and visceral graphic ads were more effective. The ad on tobacco industry denormalization that focuses on the responsibility of the industry for smoking-related harms was considered ineffective because smokers perceived it as having little personal relevance. Humorous advertisements were evaluated as the least effective because they lacked strong emotional content linked to smoking consequences. Qualitative results suggest that advertisement characteristics are more important than the demographic characteristics of people featured in advertisements. Study findings provide preliminary evidence that testimonial ads that involve graphic and emotionally evocative portrayals of smoking-attributed diseases and visceral graphic ads may have the greater potential to motivate Taiwanese smokers to quit smoking.
Slater, Michael D
2006-01-01
While increasingly widespread use of behavior change theory is an advance for communication campaigns and their evaluation, such theories provide a necessary but not sufficient condition for theory-based communication interventions. Such interventions and their evaluations need to incorporate theoretical thinking about plausible mechanisms of message effect on health-related attitudes and behavior. Otherwise, strategic errors in message design and dissemination, and misspecified campaign logic models, insensitive to campaign effects, are likely to result. Implications of the elaboration likelihood model, attitude accessibility, attitude to the ad theory, exemplification, and framing are explored, and implications for campaign strategy and evaluation designs are briefly discussed. Initial propositions are advanced regarding a theory of campaign affect generalization derived from attitude to ad theory, and regarding a theory of reframing targeted health behaviors in those difficult contexts in which intended audiences are resistant to the advocated behavior or message.
Jung, Wan S; Villegas, Jorge
2011-01-01
Anti-smoking Public Service Announcements (PSAs) typically emphasize the negative consequences of failing to quit smoking (negative frame), as opposed to emphasizing the benefits of quitting (positive frame). However, stressing the benefits of quitting sometimes produces better communication outcomes. Previous research on message framing has tried to identify factors affecting the impact of positive framing and negative framing. Data were collected on 188 undergraduates attending a southeastern university in the United States who were assigned randomly to view either positive or negative messages. Our study found that involvement and nicotine dependence moderated the impact of framed smoking-cessation messages on attitude toward the ad.
Glinert, Lewis H; Schommer, Jon C
2005-06-01
Considerable attention has been afforded to analyzing the content of and assessing consumers' reaction to print direct-to-consumer drug ads, but not so for televised ads. To determine whether advertisements with different risk severity and risk presentation would significantly affect viewers' (1) recall of information contained in the advertisement, (2) evaluation of the advertisement, and (3) perceptions of the advertised product's risks. Data were collected from a sample of 135 first-year pharmacy students at a Midwestern college of pharmacy. After viewing 1 of the 6 advertisements designed for this study, participants were asked to complete a self-administered survey. Chi-square and analysis of variance were used to analyze the data. A 2x3 between subjects design was used to test the effects of 2 levels of risk severity (high- vs low-risk severity) and 3 levels of risk presentation (original ad containing integrated risk message, deintegrated risk message/dual modality using male voice-over, deintegrated risk message/dual modality using female voice-over). Results of analysis of variance procedures revealed that deintegrating risk information by placing it at the end of the advertisement and the use of captions in addition to oral messages (dual modality) (1) improved the recall of general and specific side effect information, (2) led to a perception that the advertisement had greater informational content, (3) resulted in lower Advertisement Distraction, and (4) lessened cognitive and affective aspects of information overload for the advertisement containing the high-risk severity medication. However, this pattern of findings was not found for the low-risk severity medication. Alternative methods for presenting risk information in direct-to-consumer ads affected some aspects of information recall and advertisement evaluation, but were not shown to affect risk perceptions regarding the advertised products.
The Pitch: How To Analyze Ads. 2nd Edition.
ERIC Educational Resources Information Center
Rank, Hugh
This book probes the ways ads persuade people to purchase, and attempts to teach individuals to become more discerning consumers. Critical thinking, when applied to analyzing ads, benefits consumers by helping them recognize patterns of persuasion and sort incoming information in order to get to the hidden message. The book s basic premise is that…
ERIC Educational Resources Information Center
Wilton, Jennifer
1990-01-01
Reporting occupies a central place in institutional research but is ongoing and never completed. With automation and data management, the proportion of time spent on either routine or ad hoc reporting should decline. This function need not draw unnecessarily from resources for more interesting work. (MSE)
76 FR 19793 - Advisory Committee for Polar Programs; Notice of Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-08
... presentations and discussion on opportunities and challenges for polar research, education and infrastructure; discussion of OPP Strategic Vision development; transformative research, ad hoc proposals & program... advise NSF on the impact of its policies, programs, and [[Page 19794
Taming Pipelines, Users, and High Performance Computing with Rector
NASA Astrophysics Data System (ADS)
Estes, N. M.; Bowley, K. S.; Paris, K. N.; Silva, V. H.; Robinson, M. S.
2018-04-01
Rector is a high-performance job management system created by the LROC SOC team to enable processing of thousands of observations and ancillary data products as well as ad-hoc user jobs across a 634 CPU core processing cluster.
HEURISTIC OPTIMIZATION AND ALGORITHM TUNING APPLIED TO SORPTIVE BARRIER DESIGN
While heuristic optimization is applied in environmental applications, ad-hoc algorithm configuration is typical. We use a multi-layer sorptive barrier design problem as a benchmark for an algorithm-tuning procedure, as applied to three heuristics (genetic algorithms, simulated ...
48 CFR 1336.602-2 - Evaluation boards.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Evaluation boards. 1336...-2 Evaluation boards. Permanent and ad hoc architect-engineer evaluation boards may include... evaluation boards should be comprised of at least a majority of government personnel. ...
76 FR 80890 - Pacific Fishery Management Council; Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2011-12-27
... Fishery Management Council; Public Meeting AGENCY: National Marine Fisheries Service (NMFS), National... Pacific Fishery Management Council's (Pacific Council) Ad Hoc Groundfish Essential Fish Habitat Review... Airport Hotel, 7900 NE 82nd Avenue, Portland, OR 97220. Council address: Pacific Fishery Management...
Ultra-wideband radar sensors and networks
Leach, Jr., Richard R; Nekoogar, Faranak; Haugen, Peter C
2013-08-06
Ultra wideband radar motion sensors strategically placed in an area of interest communicate with a wireless ad hoc network to provide remote area surveillance. Swept range impulse radar and a heart and respiration monitor combined with the motion sensor further improves discrimination.
78 FR 9888 - Pacific Fishery Management Council; Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-12
... Pacific Fishery Management Council's (Council) Ad Hoc Amendment 24 Workgroup will hold an online webinar... Fishery Management Council; Public Meeting AGENCY: National Marine Fisheries Service (NMFS), National...- 508 when prompted. Council address: Pacific Fishery Management Council, 7700 NE Ambassador Place...
Anderson, Clive; Gallo, Maria F.; Hylton-Kong, Tina; Steiner, Markus J.; Hobbs, Marcia M.; Macaluso, Maurizio; Figueroa, J. Peter; Jamieson, Denise J.; Legardy-Williams, Jennifer; Wiener, Jeffrey; Warner, Lee
2013-01-01
Background The effectiveness of counseling messages to avoid unprotected sex during short-term treatment for curable sexually transmitted infections is unknown. Methods We randomized 300 female STI clinic patients 18 years or older with cervicitis and/or vaginal discharge in Kingston, Jamaica, in 2010 to 2011, to 1 of 2 counseling messages for their course of syndromic treatment: abstinence only or abstinence backed up by condom use. At a follow-up visit 6 days afterward, we collected vaginal swabs to test for prostate-specific antigen (PSA), a biological marker of recent semen exposure, and administered a questionnaire assessing sexual behavior. Results No differences were found in the proportions of women testing positive for PSA at follow-up in the abstinence-plus-condom group (11.9%) and abstinence-only group (8.4%) (risk difference, 3.5; 95% confidence interval, −3.5 to 10.5). There also was no significant difference in reporting of unprotected sex between groups. Reporting a history of condom use before enrollment significantly modified the effect of counseling arm on PSA positivity (P = 0.03). Among those reporting recent condom use, 10.3% in the abstinence-only arm and 4.8% in the abstinence-plus-condom arm tested positive for PSA. Conversely, among those not reporting recent condom use, 6.5% in the abstinence-only arm and 17.3% in the abstinence-plus-condom arm had PSA detected. Conclusions We found no evidence to support the superiority of either counseling message. Post hoc analyses suggest that women with recent condom experience may benefit significantly more from abstinence-plus-condom messages, whereas women without such experience may benefit significantly more from abstinence-only messages. Providers should weigh individual condom use history when determining the most appropriate counseling message. PMID:23321990
The Challenges of Internetworking Unattended Autonomous Sensors
2006-12-01
number of nodes that can hear the broadcast by a squared factor. The establishment of path keys for multi-hop range extension should however be used...Conf. on Info. Sci. and Syst. (CISS ), Baltimore, 21-23 March 2001 [9] R . Ramanathan, “On the Performance of Ad Hoc Networks with Beamforming...Computing”, Prentice Hall PTR, 2002 [12] S. Slijepcevic, M. Potkonjak, V. Tsiatsis, S. Zimbeck, M.B. Srivastava “On Communication Security inWireless Ad
ERIC Educational Resources Information Center
Seo, Kay Kyeongju
2007-01-01
This study focused on the effects of peer moderation on meaningful interactions in online discussions. A meaningful interaction was defined as a message relating to a discussion topic, responding to a previous message, and adding substance to the discussion. A randomized-subject, posttest-only control group design was used to test the first…
ERIC Educational Resources Information Center
Hall, P. Cougar; Lindsay, Gordon B.; West, Joshua H.
2011-01-01
The influence of media on adolescents' health practices and behaviors, including personal values, beliefs, and perceived norms cannot be overstated. Youth media consumption continues to increase. Media messages are carefully designed to persuade the consumer to believe or do something. Some of the most persuasive media messages can be found in…
The White-hat Bot: A Novel Botnet Defense Strategy
2012-06-14
etc. I will briefly discuss one common exploit here. One fraudulent activity 4 perpetuated by botnets involves ad services such as Google’s AdSense ...which pays website owners revenue for posting the AdSense banner on their web site (Google, 2012). The AdSense banner displays messages from...botmaster creates a bot that is programmed to visit the botmaster’s own websites to click on the advertisements displayed in the AdSense banners. Since
ZHAO, XIAOQUAN; ALEXANDER, TESFA N.; HOFFMAN, LEAH; JONES, CHAUNETTA; DELAHANTY, JANINE; WALKER, MATTHEW; BERGER, AMANDA T.; TALBERT, EMILY
2016-01-01
In February 2014, the Food and Drug Administration launched The Real Cost, a national youth tobacco prevention campaign. This article examines youth receptivity to potential campaign ads using data from 3 message pretesting studies featuring the same design and consistent instrumentation. A total of 3,258 adolescents ages 13–17 were randomized to either an ad-viewing condition or a no-exposure control condition. Perceived ad effectiveness, smoking-related beliefs, and attitudes were measured as outcome variables. The sample consisted of both experimental smokers (58%) and current nonsmokers at risk for cigarette initiation (42%). A total of 14 ads were tested across the three studies. Participants who viewed the ads generally considered them to be effective (with a mean perceived ad effectiveness score of 3.66 on a scale from 1 to 5). Compared to those in the control condition, participants in the ad-viewing condition reported stronger beliefs about the health risks of smoking (p < .001), a greater likelihood that smoking would lead to loss of control in life (p < .001), and more negative attitudes toward smoking (p < .001). Responses to campaign ads were largely consistent between experimenters and at-risk nonsmokers. Implications of the findings for the campaign are discussed. PMID:27736365
Marketing physical activity: lessons learned from a statewide media campaign.
Peterson, Michael; Abraham, Avron; Waterfield, Allan
2005-10-01
Steps taken to create, implement, and initially assess a statewide physical activity social marketing campaign targeted to 18-to 30-year-olds are presented. Included is a summary demonstration of the application of the associative group analysis in formative market research and message development. Initial postcampaign questionnaire (n = 363) results indicated that 39.1% of respondents had seen the television ad, of which 31.2% indicated they intended to be more active, and 62.5% of respondents had been exposed to either the television or outdoor media ads. Lessons learned through the social marketing process including media channel effectiveness, message development and assessment, and marketing firm relationships are provided.
Evidence of the dose effects of an antitobacco counteradvertising campaign.
Sly, David F; Trapido, Ed; Ray, Sarah
2002-11-01
The objectives were to assess the cumulative effects of exposure to multiple antitobacco advertisements shown over a 22-month period on smoking uptake, and determine if there is evidence of a dose effect and how this effect operates through response to the campaign's major message theme and antitobacco attitudes. A follow-up telephone survey of persons ages 12-20 years was conducted after 22 months of the Florida "truth" antitobacco media campaign. Logistic regression analyses were used to estimate adjusted odds ratios for the likelihood that time-one nonsmokers would remain nonsmokers at time two by levels of confirmed advertisement awareness, self-reported influence of the campaign's message theme, and anti-tobacco industry manipulation attitudes. Separate cohorts are analyzed and controls include gender and time-one susceptibility. The likelihood of nonsmokers remaining nonsmokers increases as the number of ads confirmed, the self-reported influence of the campaign's major message theme, and the level of antitobacco attitudes increases. The pattern to these relationships holds within cohorts of young and older youth and for a cohort that has aged into the early young adult years. Considering all variables simultaneously suggests that ad confirmation operates through its effects on the influence of the message theme and antitobacco industry manipulation attitudes. There is evidence of a dose effect; however, considering only ad confirmation underestimates this. Antitobacco campaigns that target youth can have effects at least through the early young adult ages. The uniqueness of the Florida campaign may limit the generalization of reported results.
77 FR 31329 - Pacific Fishery Management Council; Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-25
... Fishery Management Council; Public Meeting AGENCY: National Marine Fisheries Service (NMFS), National... Pacific Fishery Management Council's (Pacific Council) ad hoc South of Humbug Pacific Halibut Workgroup (SHPHW) will hold a conference call to review background material on Pacific Halibut stock assessment...
7 CFR 3400.14 - Proposal review.
Code of Federal Regulations, 2010 CFR
2010-01-01
... SERVICE, DEPARTMENT OF AGRICULTURE SPECIAL RESEARCH GRANTS PROGRAM Scientific Peer Review of Research... employees of the Department, the respective peer review group, and ad hoc reviewers, as required. Written...-depth discussions will be provided by peer review group members prior to recommending applications for...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-30
..., 2014, 10:00 a.m. to 3:30 p.m. Place: Virtual via Webinar. Status: The meeting is open to the public...) updates from the Committee's subcommittees and ad-hoc workgroups including Laboratory Standards and...
The Integration of Small Satellites in Maritime Interdiction Operations (MIO)
2012-09-01
Interdiction Operation, Networks, Ad-Hoc Networks, AISSat-1, Adaptation, Weak Links, Satellite Tool Kit ( STK ), Tactical Network Topology (TNT). 15. NUMBER...43 B. STK .................................................................................................... 47 1. STK Modeling of... STK ............................. 69 1. Create the Six Satellites ........................................................ 69 2. Create the Facility
ERIC Educational Resources Information Center
Thomas, Gary
1997-01-01
Argues against the use of theory in educational inquiry, contending that the meaning of theory is unclear; both personal theory and grand theory inhibit creativity and methodology; and less structured problem solving and ad hoc approaches are more likely to result in pluralistic ideas. (SK)
48 CFR 1436.602-2 - Evaluation boards.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Evaluation boards. 1436...-2 Evaluation boards. HCAs shall establish procedures for providing permanent or ad hoc architect-engineer evaluation boards. Bureau procedures shall provide for the appointment of private practitioners of...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-25
... DEPARTMENT OF STATE [Public Notice 8251] Preparations for the International Telecommunication Union World Telecommunication Development Conference (ITU WTDC 2014) SUMMARY: This notice announces... the activities of its ad hoc group for preparations for the ITU World Telecommunication Development...
7 CFR 3415.14 - Proposal review.
Code of Federal Regulations, 2013 CFR
2013-01-01
... BIOTECHNOLOGY RISK ASSESSMENT RESEARCH GRANTS PROGRAM Scientific Peer Review of Research Grant Applications...., relationship of application to announced program area). Proposals that do not fall within the guidelines as... officers or employees of the Department, the respective peer review group, and ad hoc reviewers, as...
7 CFR 3415.14 - Proposal review.
Code of Federal Regulations, 2014 CFR
2014-01-01
... BIOTECHNOLOGY RISK ASSESSMENT RESEARCH GRANTS PROGRAM Scientific Peer Review of Research Grant Applications...., relationship of application to announced program area). Proposals that do not fall within the guidelines as... officers or employees of the Department, the respective peer review group, and ad hoc reviewers, as...
7 CFR 3415.14 - Proposal review.
Code of Federal Regulations, 2012 CFR
2012-01-01
... BIOTECHNOLOGY RISK ASSESSMENT RESEARCH GRANTS PROGRAM Scientific Peer Review of Research Grant Applications...., relationship of application to announced program area). Proposals that do not fall within the guidelines as... officers or employees of the Department, the respective peer review group, and ad hoc reviewers, as...
78 FR 68480 - National Science Board
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-14
... NATIONAL SCIENCE FOUNDATION National Science Board The National Science Board's ad hoc Committee on Honorary Awards, pursuant to NSF regulations (45 CFR part 614), the National Science Foundation... gives notice in regard to the scheduling of a meeting for the transaction of National Science Board...
Sgueglia, Gregory A; Todaro, Daniel; De Santis, Antonella; Conte, Micaela; Gioffrè, Gaetano; Di Giorgio, Angela; D'Errico, Fabrizio; Piccioni, Fabiana; Summaria, Francesco; Gaspardone, Achille
2017-10-16
Transradial percutaneous coronary intervention (PCI) offers important advantages over transfemoral PCI, including better outcomes. However, when there is indication to ad hoc PCI, a 6 French workflow is a common default strategy, hence potentially influencing vascular access selection in patients with anticipated small size radial artery. A multidimensional evaluation was performed to compare two ad hoc interventional strategies in women <160cm: a full 6 French workflow (namely 6 French introducer sheath, diagnostic catheters and guiding catheter) with a modified workflow consisting in the use of 5 French diagnostic catheters preceded by the placement of a 6 French sheath introducer and followed by a 6 French guiding catheter use for PCI. Overall 120 women (68±11years) were enrolled in the study. Coronary angiography has been performed using 5 French or 6 French diagnostic catheters in 57 (47.5%) and 63 (52.5%) cases, respectively. Radial spasm and switch to another access occurred more frequently among women who underwent coronary angiography with 6 French rather than 5 French diagnostic catheters (43% vs. 25%, p=0.03 and 2% vs. 11%, p=0.04, respectively). Total time to guidewire lesion crossing was also significantly higher when PCI has been preceded by 6 French rather than 5 French coronary angiography (23±11min vs 16±7min, p=0.013). In patients with anticipated unfavorable radial access, a workflow consisting in 6 French introducer sheath placement, 5 French coronary angiography, and 6 French coronary intervention is on multiple parameters the most straightforward and effective strategy. Copyright © 2017 Elsevier Inc. All rights reserved.
Statistically Self-Consistent and Accurate Errors for SuperDARN Data
NASA Astrophysics Data System (ADS)
Reimer, A. S.; Hussey, G. C.; McWilliams, K. A.
2018-01-01
The Super Dual Auroral Radar Network (SuperDARN)-fitted data products (e.g., spectral width and velocity) are produced using weighted least squares fitting. We present a new First-Principles Fitting Methodology (FPFM) that utilizes the first-principles approach of Reimer et al. (2016) to estimate the variance of the real and imaginary components of the mean autocorrelation functions (ACFs) lags. SuperDARN ACFs fitted by the FPFM do not use ad hoc or empirical criteria. Currently, the weighting used to fit the ACF lags is derived from ad hoc estimates of the ACF lag variance. Additionally, an overcautious lag filtering criterion is used that sometimes discards data that contains useful information. In low signal-to-noise (SNR) and/or low signal-to-clutter regimes the ad hoc variance and empirical criterion lead to underestimated errors for the fitted parameter because the relative contributions of signal, noise, and clutter to the ACF variance is not taken into consideration. The FPFM variance expressions include contributions of signal, noise, and clutter. The clutter is estimated using the maximal power-based self-clutter estimator derived by Reimer and Hussey (2015). The FPFM was successfully implemented and tested using synthetic ACFs generated with the radar data simulator of Ribeiro, Ponomarenko, et al. (2013). The fitted parameters and the fitted-parameter errors produced by the FPFM are compared with the current SuperDARN fitting software, FITACF. Using self-consistent statistical analysis, the FPFM produces reliable or trustworthy quantitative measures of the errors of the fitted parameters. For an SNR in excess of 3 dB and velocity error below 100 m/s, the FPFM produces 52% more data points than FITACF.
NASA Astrophysics Data System (ADS)
Huang, Feng; Sun, Lifeng; Zhong, Yuzhuo
2006-01-01
Robust transmission of live video over ad hoc wireless networks presents new challenges: high bandwidth requirements are coupled with delay constraints; even a single packet loss causes error propagation until a complete video frame is coded in the intra-mode; ad hoc wireless networks suffer from bursty packet losses that drastically degrade the viewing experience. Accordingly, we propose a novel UMD coder capable of quickly recovering from losses and ensuring continuous playout. It uses 'peg' frames to prevent error propagation in the High-Resolution (HR) description and improve the robustness of key frames. The Low-Resolution (LR) coder works independent of the HR one, but they can also help each other recover from losses. Like many UMD coders, our UMD coder is drift-free, disruption-tolerant and able to make good use of the asymmetric available bandwidths of multiple paths. The simulation results under different conditions show that the proposed UMD coder has the highest decoded quality and lowest probability of pause when compared with concurrent UMDC techniques. The coder also has a comparable decoded quality, lower startup delay and lower probability of pause than a state-of-the-art FEC-based scheme. To provide robustness for video multicast applications, we propose non-end-to-end UMDC-based video distribution over a multi-tree multicast network. The multiplicity of parents decorrelates losses and the non-end-to-end feature increases the throughput of UMDC video data. We deploy an application-level service of LR description reconstruction in some intermediate nodes of the LR multicast tree. The principle behind this is to reconstruct the disrupted LR frames by the correctly received HR frames. As a result, the viewing experience at the downstream nodes benefits from the protection reconstruction at the upstream nodes.
Park, Sun-Young
2012-01-01
This study investigates the effects of framing and risk perception, and their interaction effects on human papillomavirus (HPV) vaccination. Based on a 2 (message frames) × 2 (perceived risk) experimental design, the interaction effects reveal the effectiveness of loss- (vs. gain-) framed messages would be maximized for high (vs. low) perceived risk condition. Based on regulatory fit principles the synergy effects are shown in terms of attitudes toward advertising and HPV vaccination, HPV vaccination intention, and ad-promoted behavioral intention. The findings indicate right message appeals should be selected for the right target audiences in the setting of HPV vaccine promotions.
Lee, Sungkyoung; Cappella, Joseph N; Lerman, Caryn; Strasser, Andrew A
2013-02-01
This study examines the impact of smoking cues employed in antismoking advertisements on former smokers. Previous findings indicate that visual smoking cues in antismoking advertisements with weak antismoking arguments can elicit smoking urges in smokers and undermine message effectiveness. This study extends these observations to former smokers asking whether smoking cues in antismoking advertisements influence former smokers' self-efficacy, attitudes, and intention to refrain from smoking, along with smoking urges and perceived message effectiveness. The study was a mixed 2 (smoking cues; present vs. absent) × 2 (argument strength [AS]; high vs. low) design where smoking cue was a between-subject factor and AS was a within-subject factor. Potential participants recruited via online ads were screened in a phone interview for their eligibility. A total of 105 former smokers (aged 21-65) participated in the study, which was conducted in a laboratory setting. Repeated measure ANOVA and MANOVA were used for the analyses. The results showed that the presence of smoking cues in antismoking ads undermines former smokers' behavioral self-efficacy, attitude, and intention about smoking abstinence, which increased as AS for the ads increased. Former smokers' reports of smoking urge were not affected by smoking cues or AS. However, consistent with previous findings for smokers, the presence of cues weakened perceived message effectiveness of antismoking ads rated by former smokers. The effect of smoking cues on former smokers' self-efficacy, attitude, and intention to refrain from smoking is problematic. Inclusion of smoking cues in antismoking ads should be undertaken only when accompanied by strong arguments.
Audience Design through Social Interaction during Group Discussion
Rogers, Shane L.; Fay, Nicolas; Maybery, Murray
2013-01-01
This paper contrasts two accounts of audience design during multiparty communication: audience design as a strategic individual-level message adjustment or as a non-strategic interaction-level message adjustment. Using a non-interactive communication task, Experiment 1 showed that people distinguish between messages designed for oneself and messages designed for another person; consistent with strategic message design, messages designed for another person/s were longer (number of words) than those designed for oneself. However, audience size did not affect message length (messages designed for different sized audiences were similar in length). Using an interactive communication task Experiment 2 showed that as group size increased so too did communicative effort (number of words exchanged between interlocutors). Consistent with a non-strategic account, as group members were added more social interaction was necessary to coordinate the group's collective situation model. Experiment 3 validates and extends the production measures used in Experiment 1 and 2 using a comprehension task. Taken together, our results indicate that audience design arises as a non-strategic outcome of social interaction during group discussion. PMID:23437343
Population-based evaluation of the 'LiveLighter' healthy weight and lifestyle mass media campaign.
Morley, B; Niven, P; Dixon, H; Swanson, M; Szybiak, M; Shilton, T; Pratt, I S; Slevin, T; Hill, D; Wakefield, M
2016-04-01
The Western Australian (WA) 'LiveLighter' (LL) mass media campaign ran during June-August and September-October 2012. The principal campaign ad graphically depicts visceral fat of an overweight individual ('why' change message), whereas supporting ads demonstrate simple changes to increase activity and eat healthier ('how' to change message). Cross-sectional surveys among population samples aged 25-49 were undertaken pre-campaign (N= 2012) and following the two media waves (N= 2005 and N= 2009) in the intervention (WA) and comparison state (Victoria) to estimate the population impact of LL. Campaign awareness was 54% after the first media wave and overweight adults were more likely to recall LL and perceive it as personally relevant. Recall was also higher among parents, but equal between socio-economic groups. The 'why' message about health-harms of overweight rated higher than 'how' messages about lifestyle change, on perceived message effectiveness which is predictive of health-related intention and behaviour change. State-by-time interactions showed population-level increases in self-referent thoughts about the health-harms of overweight (P < 0.05) and physical activity intentions (P < 0.05). Endorsement of stereotypes of overweight individuals did not increase after LL aired. LL was associated with some population-level improvements in proximal and intermediate markers of campaign impact. However, sustained campaign activity will be needed to impact behaviour. © The Author 2016. Published by Oxford University Press.
Population-based evaluation of the ‘LiveLighter’ healthy weight and lifestyle mass media campaign
Morley, B.; Niven, P.; Dixon, H.; Swanson, M.; Szybiak, M.; Shilton, T.; Pratt, I. S.; Slevin, T.; Hill, D.; Wakefield, M.
2016-01-01
The Western Australian (WA) ‘LiveLighter’ (LL) mass media campaign ran during June–August and September–October 2012. The principal campaign ad graphically depicts visceral fat of an overweight individual (‘why’ change message), whereas supporting ads demonstrate simple changes to increase activity and eat healthier (‘how’ to change message). Cross-sectional surveys among population samples aged 25–49 were undertaken pre-campaign (N = 2012) and following the two media waves (N = 2005 and N = 2009) in the intervention (WA) and comparison state (Victoria) to estimate the population impact of LL. Campaign awareness was 54% after the first media wave and overweight adults were more likely to recall LL and perceive it as personally relevant. Recall was also higher among parents, but equal between socio-economic groups. The ‘why’ message about health-harms of overweight rated higher than ‘how’ messages about lifestyle change, on perceived message effectiveness which is predictive of health-related intention and behaviour change. State-by-time interactions showed population-level increases in self-referent thoughts about the health-harms of overweight (P < 0.05) and physical activity intentions (P < 0.05). Endorsement of stereotypes of overweight individuals did not increase after LL aired. LL was associated with some population-level improvements in proximal and intermediate markers of campaign impact. However, sustained campaign activity will be needed to impact behaviour. PMID:26956039
76 FR 51378 - National Cancer Institute; Notice of Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-18
... DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of Health National Cancer Institute.... App.), notice is hereby given of a meeting of the National Cancer Institute Board of Scientific... Committee: National Cancer Institute Board of Scientific Advisors, caBIG Oversight Ad hoc Subcommittee. Date...
DOT National Transportation Integrated Search
2012-01-01
This report discusses the approach and findings of a research project aimed at the evaluation of : an inter-vehicle communications scheme for Vehicular Ad hoc Networks (VANETs). : Because of the size, frequency, and expected number of receivers of pe...
Despite the increasing promotion of stakeholder engagement in science contributing to environmental decision making, the mechanisms for identifying which stakeholders should be included are rarely strategic or documented. When documented, many of these efforts use ad hoc and/or ...
A Guide for Hard Times in Academia
ERIC Educational Resources Information Center
Reeves, Thomas C.
2003-01-01
The author lampoons twenty-first-century academic priorities. Using a fictional campus facing state-mandated budget reductions, the author parodies a system that retains high-salaried administrative and public relations positions, special-interest majors, athletic programs and junior/ad-hoc faculty, while relinquishing admissions staff, library…
77 FR 9211 - South Atlantic Fishery Management Council; Public Meetings
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-16
... Panel; Ad Hoc Data Collection Committee; Law Enforcement Committee; Spiny Lobster Committee; Ecosystem... Amendment 20B (wreckfish Individual Transferable Quota (ITQ) program modifications); Spiny Lobster Amendment... report from the Law Enforcement AP and discuss other issues as appropriate. 4. Spiny Lobster Committee...
77 FR 45591 - Pacific Fishery Management Council; Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-01
... Fishery Management Council; Public Meeting AGENCY: National Marine Fisheries Service (NMFS), National... Pacific Fishery Management Council's (Pacific Council) Ad Hoc South of Humbug Pacific Halibut Workgroup..., monitoring, and allocation history of Pacific halibut in the area south of Humbug Mt. DATES: The conference...
2015-06-01
raspberry pi , robotic operation system (ros), arduino 15. NUMBER OF PAGES 123 16. PRICE CODE 17. SECURITY CLASSIFICATION OF REPORT...51 2. Raspberry Pi ...52 Figure 21. The Raspberry Pi B+ model, from [24
Relationships in Data Sanitization: A Study in Scarlet
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bishop, Matt; Cummins, Justin; Peisert, Sean
2010-09-23
Data anonymization and sanitization are essential components to using and sharing data, but most approaches to performing those actions either fail to take into account all of the stakeholders, are ad hoc, or both. In this paper, we discuss a means of doing so.
Using expert opinion to quantify accuracy and reliability of nondestructive evaluation on bridges.
DOT National Transportation Integrated Search
2015-08-01
Bridge inspection is an important phase in bridge management. In 2009, a joint American Society of Civil : Engineers Structural Engineering Institute and AASHTO Ad-Hoc group was created to identify the issues : in bridge safety and to study current b...
Trust Management and Accountability for Internet Security
ERIC Educational Resources Information Center
Liu, Wayne W.
2011-01-01
Adversarial yet interacting interdependent relationships in information sharing and service provisioning have been a pressing issue of the Internet. Such relationships exist among autonomous software agents, in networking system peers, as well as between "service users and providers." Traditional "ad hoc" security approaches effective in…
76 FR 77840 - Statement of Organization, Functions and Delegations of Authority
Federal Register 2010, 2011, 2012, 2013, 2014
2011-12-14
... current liaison functions and grant policy processes within the Office of Federal Assistance Management... processes related to assistance programs; (3) facilitates, plans, directs and coordinates the administration... review of grant applicants' and grantees' accounting systems; (5) conducts ad hoc studies and reviews...