Reducing Routing Overhead in Random Walk Protocol under MP2P Network

Due to network dynamics in self-organizing networks the resource discovery effort increases. To discover objects in unstructured peer-to-peer network, peers rely on traditional methods like flooding, random walk and probabilistic forwarding methods. With inadequate knowledge of paths, the peers have to flood the query message which creates incredible network traffic and overhead. Many of the previous works based on random walk were done in wired network. In this context random walk was better than flooding. But under MANETs random walk approach behaved differently increasing the overhead, due to frequent link failures incurred by mobility. Decentralized applications based on peer-to-peer computing are best candidates to run over such dynamic network. Issues of P2P service discovery in wired networks have been well addressed in several earlier works. This article evaluates the performance of random walk based resource discovery protocol over P2P Mobile Adhoc Network (MP2P) and suggests an improved scheme to suit MANET. Our version reduces the network overhead, lowers the battery power consumption, minimizes the query delay while providing equally good success rate. The protocol is validated through extensive NS-2 simulations. It is clear from the results that our proposed scheme is an alternative to the existing ones for such highly dynamic mobile network scenario

An adaptive approach to service discovery in ad hoc networks

Service discovery allows the interaction between network nodes to cooperate in activities or to share resources in client-server, multi-layer, as well as in peer-to-peer architectures. Ad hoc networks pose a great challenge in the design of efficient mechanisms for service discovery. The lack of infrastructure along with node mobility makes it difficult to build robust, scalable and secure mechanisms for ad hoc networks. This paper proposes a scalable service discovery architecture based on directory nodes organized in an overlay network. In the proposed architecture, directory nodes are dynamically created with the aim of uniformly covering the entire network while decreasing the query latency for a service (QoS) and the number of control messages for the sake of increased scalability.8th IFIP/IEEE International conference on Mobile and Wireless CommunicationRed de Universidades con Carreras en Informática (RedUNCI

An adaptive approach to service discovery in ad hoc networks

Service discovery allows the interaction between network nodes to cooperate in activities or to share resources in client-server, multi-layer, as well as in peer-to-peer architectures. Ad hoc networks pose a great challenge in the design of efficient mechanisms for service discovery. The lack of infrastructure along with node mobility makes it difficult to build robust, scalable and secure mechanisms for ad hoc networks. This paper proposes a scalable service discovery architecture based on directory nodes organized in an overlay network. In the proposed architecture, directory nodes are dynamically created with the aim of uniformly covering the entire network while decreasing the query latency for a service (QoS) and the number of control messages for the sake of increased scalability.8th IFIP/IEEE International conference on Mobile and Wireless CommunicationRed de Universidades con Carreras en Informática (RedUNCI

Data replication and update propagation in XML P2P data management systems

XML P2P data management systems are P2P systems that use XML as the underlying data format shared between peers in the network. These systems aim to bring the benefits of XML and P2P systems to the distributed data management field. However, P2P systems are known for their lack of central control and high degree of autonomy. Peers may leave the network at any time at will, increasing the risk of data loss. Despite this, most research in XML P2P systems focus on novel and efficient XML indexing and retrieval techniques. Mechanisms for ensuring data availability in XML P2P systems has received comparatively little attention. This project attempts to address this issue. We design an XML P2P data management framework to improve data availability. This framework includes mechanisms for wide-spread data replication, replica location and update propagation. It allows XML documents to be broken down into fragments. By doing so, we aim to reduce the cost of replicating data by distributing smaller XML fragments throughout the network rather than entire documents. To tackle the data replication problem, we propose a suite of selection and placement algorithms that may be interchanged to form a particular replication strategy. To support the placement of replicas anywhere in the network, we use a Fragment Location Catalogue, a global index that maintains the locations of replicas. We also propose a lazy update propagation algorithm to propagate updates to replicas. Experiments show that the data replication algorithms improve data availability in our experimental network environment. We also find that breaking XML documents into smaller pieces and replicating those instead of whole XML documents considerably reduces the replication cost, but at the price of some loss in data availability. For the update propagation tests, we find that the probability that queries return up-to-date results increases, but improvements to the algorithm are necessary to handle environments with high update rates

Schema matching in a peer-to-peer database system

Includes bibliographical references (p. 112-118).Peer-to-peer or P2P systems are applications that allow a network of peers to share resources in a scalable and efficient manner. My research is concerned with the use of P2P systems for sharing databases. To allow data mediation between peers' databases, schema mappings need to exist, which are mappings between semantically equivalent attributes in different peers' schemas. Mappings can either be defined manually or found semi-automatically using a technique called schema matching. However, schema matching has not been used much in dynamic environments, such as P2P networks. Therefore, this thesis investigates how to enable effective semi-automated schema matching within a P2P network

The Role Of Social Support In Breastfeeding Experiences Among Rural Women In Southern Appalachia

Objectives: The objectives of this study are: 1) to describe breastfeeding experiences and level of social support received among WIC participants in southern Appalachia, 2) to examine perceived types and effectiveness of social support received including emotional, instrumental, informational, and appraisal.Design, Setting, and Participants: Data was collected using a semi structured qualitative interview (n = 7). Breastfeeding and postpartum WIC participants were recruited to participate via the placement of flyers in three WIC clinics in western North Carolina. ASU IRB approved the study.Outcome Measures and Analysis: A semi-structured interview was conducted to assess breastfeeding experiences, barriers, and level of support received. Interviews were transcribed verbatim. Grounded theory approach (Glaser, 1967) was applied and themes were organized as they emerged. Interviews were coded using Nvivo software (QSR International, 2013).Results: Each interview lasted approximately one hour. The mean age was 29 and the average monthly income was $1,723. Participants reported a high level of support from partners (e.g. husbands), professionals (e.g. lactation consultants and WIC), and the maternal grandmother of the infant. Commonly reported themes included receipt of professional support (11 mentions), difficulty breastfeeding (13 mentions), and desire to breastfeed for health benefits and bonding (27 mentions).Conclusions and Implications: The interview results indicated that even with strong social support, obstacles such as sexist social norms still exist for breastfeeding mothers. Professionals specializing in breastfeeding, such as WIC staff and lactation consultants, tended to be more helpful than other health professionals Partners were a strong source of support for married mothers, and tended to have input on breastfeeding duration. Emotional, appraisal, and informational support were perceived as effective support for breastfeeding initiation and duration

Factors Influencing the Adoption of Immersive Virtual Reality for Individuals with Autism Spectrum Disorder: Parents Perceptions

The purpose of this qualitative study was to identify factors that affect the adoption of a spherical video virtual reality (SVVR) mobile application among parents of adults with Autism Spectrum Disorder (ASD). The study used the diffusion of innovation theory by Rogers (2003) as a framework to explore parents’ perceptions of an SVVR transportation model designed to improve the quality of life of adults with ASD. In addition, the study sought to learn what might increase adoption of VR technology among other parents of individuals with ASD and what life skills that might be addressed using VR technology in the future. The study employed interviews, focus groups, and observation to collect data. The factors that negatively affected the perception of VR technology among parents were categorized into themes: awareness of VR learning applications, availability, disadvantages of SVVR, and technical issues related to the SVVR transportation model. Factors that positively affected the parents’ decision to adopt VR were immersion, realism, ease-of-use, enjoyment and motivation. To increase the adoption of VR by other parents of individuals with ASD, parents suggested that understanding of VR learning applications needs to increase, more teachers should be trained to use VR, the SVVR model should be improved, and there should be greater exposure to VR in schools and at home. Potential future life skills that need to be addressed through the VR technology were also identified. The findings of this study may help eliminate concerns about using VR technology as a therapy for ASD individuals and encourage more parents, teachers, and other stakeholders to adopt it

Student participation in serious games design

Serious games can be defined simply as games with an educational intent. These games are regularly positioned within a curriculum as simple teaching agents and often lack meaningful participation from learners in their development. In 1992, Roger Hart proposed a model for the roles children play in participatory projects with adults. ‘Hart’s Ladder’ presents eight levels of children’s participation moving from tokenistic manipulation of children at the base of this ladder to ‘citizenship’ at the top where children can initiate and share activities with adults. This research contributes to knowledge on methods of integrating serious games into formal educational settings by investigating how children, as participants, can work with their educators, as facilitators, to create serious games for use by their peers. Exploratory field studies have worked with secondary school children (11-16 years) to evaluate the hypothesis that higher levels of participation of children in making serious games will produce more effective educational artefacts. Educational artefacts are context specific to each study but encompass the product and accreditation of the process by participants, facilitators and all stakeholders involved