Ad-hoc System Research Articles

S-SoDiA: a semantic enabled social diagnosis advisor

Medical information systems have recently gained momentum as a proof-of-concept of the efficiency of new support-oriented technologies, in particular, semantic technologies. In principle, diagnosis or medicine advisory and recommendation can change the current biomedical IT landscape, providing intelligent reasoning and inference support. This paper presents S-SoDiA, a social diagnosis advisor based on semantics, which aims at bridging the gap between state of the art ad-hoc e-health applications and intelligent diagnosis decision support systems.

Knuckles: bringing the database to the data

Click-stream data warehousing has emerged as a monumental information management and processing challenge for commercial enterprises. Traditional solutions based on commercial DBMS technology often suffer from poor scalability and large processing latencies. Although click-stream data tends to be collected in a distributed manner to support scaling the servers that host the websites, in general these partitioned click-stream logs are collated and pushed upstream to a centralised database storage repository, creating storage bottlenecks. In this paper, we propose a design of an ad-hoc retrieval system suitable for click-stream data warehouses, in which the data remains distributed and database queries are rewritten to be executed against the distributed data. The query rewrite does not involve any centralised control and is therefore highly scalable. The elimination of centralised control is achieved by supporting a restricted subset of SQL, which is sufficient for most click-stream data analysis. Evaluations conducted using both synthetic and real data establish the viability of this approach.

Generic link cost estimation for large number of moving mobiles by using two-array method based on N-partite mechanism in ad-hoc networks

A multi-cluster multi-group wireless network architecture for modern ad-hoc adaptive mobile link information system is presented. The proposed network architecture supports multi-media traffic and relies on both time-division-multiplexing (TDM) and frequency-division-multiplexing (FDM). This architecture is not supported by a wires infrastructure as conventional cellular system. This paper applying a generic method to estimate the mobile location caused from mobile mobility where the mobile nodes are associated and disassociated into clusters. In our study, the complete graph is adopted for link constructions and link cost is prior than without using estimation. The topology for link estimation is scalable to larger number of nodes, and can handle the instant mobility in the mobile environments.

Amplify-and-forward with partial relay selection

This letter offers a statistical analysis of the basic two-hop Amplify-and-Forward link, where the relay node is selected based on instantaneous and partial knowledge of the channel. In contrast with previously reported work, where relay selection requires global knowledge (2 hops) of the relaying link, the problem considered is interesting in practical ad-hoc systems, where only neighboring (1 hop) channel information is available to the nodes. The probability density function of the received signal-to-noise ratio for the considered relaying link is approximated in closed form, and an asymptotic exponential expression is proposed to simplify performance estimation.

CoSP2P: A Component-Based Service Model for Peer-to-Peer Systems

The increasing complexity of software development based on peer to peer networks makes necessary the creation of new frameworks in order to simplify the developer's task. Additionally, some applications, e.g. fire detection or security alarms may require real-time constraints and the high level definition of these features eases the application development. In this paper, a service model based on a component model with real-time features is proposed. The high-level model will abstract developers from implementation tasks, such as discovery, communication, security or real-time requirements. The model is oriented to deploy services on small mobile devices, such as sensors, mobile phones and PDAs, where the computation is light-weight. Services can be composed among them by means of the port concept to form complex ad-hoc systems and their implementation is carried out using a component language called UM-RTCOM. In order to apply our proposals a fire detection application is described.

Epidemiologic surveillance system implemented in the Hautes-Alpes District, France, during the Winter Olympic Games, Torino 2006.

Some of the competitions of the Olympic Winter Games in Torino, 10 to 26 February 2006, were organised in France near the city of Briançon, in the department of Hautes-Alpes. An epidemiologic surveillance system was set up by the local health authorities. The goals were to detect in a timely fashion any phenomenon which could justify prevention or sanitary control action, and to guide interventions in the case of outbreak or environmental pollution. Surveillance was implemented from 30 January to15 March 2006 in the Briançon area. Mortality was tracked using by analysing the number and cause of deaths. A sentinel network of general practitioners was set up and reported the frequency of acute gastroenteritis, influenza-like illness and measles. Medical laboratories provided data about the analyses they undertook. Hospital emergency department and emergency ambulance service activities were followed up. Statutory notification diseases and toxic effects of carbon monoxide surveillances were reinforced. Analysed data were transmitted daily to the health authorities. A French/English report was sent weekly to all participants. The participation rate was close to 100%, and data transmission deadlines were respected. No adverse health event was identified. The strong acceptability of this surveillance system comes from its good understanding by the participants. This surveillance, structured around routine and ad-hoc systems, allowed the establishment of the foundations of a network to be used in case of outbreak or environmental pollution.

Environmental Sensor Networks: A revolution in the earth system science?

Environmental Sensor Networks (ESNs) facilitate the study of fundamental processes and the development of hazard response systems. They have evolved from passive logging systems that require manual downloading, into ‘intelligent’ sensor networks that comprise a network of automatic sensor nodes and communications systems which actively communicate their data to a Sensor Network Server (SNS) where these data can be integrated with other environmental datasets. The sensor nodes can be fixed or mobile and range in scale appropriate to the environment being sensed. ESNs range in scale and function and we have reviewed over 50 representative examples. Large Scale Single Function Networks tend to use large single purpose nodes to cover a wide geographical area. Localised Multifunction Sensor Networks typically monitor a small area in more detail, often with wireless ad-hoc systems. Biosensor Networks use emerging biotechnologies to monitor environmental processes as well as developing proxies for immediate use. In the future, sensor networks will integrate these three elements ( Heterogeneous Sensor Networks). The communications system and data storage and integration (cyberinfrastructure) aspects of ESNs are discussed, along with current challenges which need to be addressed. We argue that Environmental Sensor Networks will become a standard research tool for future Earth System and Environmental Science. Not only do they provide a ‘virtual’ connection with the environment, they allow new field and conceptual approaches to the study of environmental processes to be developed. We suggest that although technological advances have facilitated these changes, it is vital that Earth Systems and Environmental Scientists utilise them.

Mobile Ad Hoc and Sensor Systems

Mobile Ad Hoc and Sensor Systems

Proof-Oriented Fault-Tolerant Systems Engineering: Rationales, Experiments and Open Issues

Proving system properties such as fail-safety is a challenge for systems engineering since industrial automation is nowadays embedding intensive on-site and remote infotronics components engineered with increasing intuitive ease-of-use techniques. Since a fonnal proof of the complete safe-behaviour of the resulting ad-hoc system is not possible, this paper argues that Proof Oriented Systems Engineering formal techniques should bridge the gap with Fault Tolerant Systems Engineering practical techniques in order to mathematically check the proof of fail-safety. Rationales, experiments and open issues are addressed on combining the formal B event-based method using the B proof assistant with a technical-safety modelling formalizedframework.

Location Information-Aided Task-Oriented Self-Organization of Ad-Hoc Sensor Systems

A novel task-oriented self-organization algorithm that accounts for mostly location-dependent tasks and heterogeneous sensors inherent in dense ad-hoc sensor systems is proposed. It forms a sensor group for an announced task by sequentially selecting the best matched sensors using a leader election algorithm and a residual task calculation algorithm. To improve the associated communication overhead, the sensor node location information is used in task broadcasting, thus confining the algorithm implementation to a dynamically maintained contributor group which comprises of those sensors which may contribute to the task. Sensor localization is based on a refinement of an algorithm in which utilizes only the neighborhood information of each sensor node corresponding to its each preset radio transmission power level. The proposed self-organization algorithm and how various system parameters affect its performance are examined via extensive simulations. In a densely deployed sensor system, when the refined localization scheme is demonstrated to achieve very good localization, the proposed self-organization algorithm consistently yields a sensor group that covers the announced task.

Recent Trend of Millimeter-Wave Access Systems

This paper describes the recent trend of millimeter-wave wireless access systems which utilize the advantages of millimeter-waves. The fixed wireless access systems are first discussed and newly developed testbed at Yokosuka city area for broadband transmission is introduced. Then three promising short distance wireless access systems using 60-GHz frequency are discussed. The first one is on video transmission in the house, the second on vertically -connected link for the apartment infrastructure, and the third on wireless personal area ad-hoc system. Lastly millimeter-wave self-heterodyne transmission method is briefly introduce which can decrease the complex and cost of millimeter-wave local oscillators.

Capacity evaluation of frequency hopping based ad-hoc systems

The IEEE 802.15 Wireless Personal Area Networks (WPAN) study group has been working on evolving a standard for short-range wireless connectivity between low complexity and low power devices operating within the personal operating space (POS). The scenarios envisioned for WPANs are likely to involve a large number of POSs operating in an indoor environment. Among short-range wireless technologies, Bluetooth TM 1 based ad-hoc connectivity comes closest to satisfying the WPAN requirements. Bluetooth provides a gross rate of 1 Mbps per network and allows several such networks to overlap using frequency hopping. The 'aggregate throughput' thus achieved is much higher than 1 Mbps. In the absence of external interfering sources, aggregate throughput is limited by self interference which depends upon, (i) physical layer parameters like hopping rate, hopping sequences, transmitted power, receiver sensitivity, modulation, forward error correction (ii) channel characteristics like coherence bandwidth and coherence time (iii) spatial characteristics. In this work we consider the problem of finding the capacity of Bluetooth based ad-hoc systems by accurately modeling the Bluetooth physical layer and the indoor wireless channel. We predict the throughput in Bluetooth based ad-hoc systems as a function of a generalized set of parameters using realistic scenarios and assumptions.

CADASTRAL SURVEYS IN INDIA

AbstractThere has been a great and growing need in India for the establishment or improvement of a Cadastral System as a prerequisite for accelerated development. The measures, if any, that have been taken so far to fill this need are inadequate or have failed, mainly because of lack of insight into the complexity of the problem; frequently ad-hoc systems are being established to fulfil an urgent and for local need without any thought being given to future integration into a final national system, thus contributing to the often existing confusion, and to a waste of energy and money. The paper describes cadastral surveying practice in India from the earliest times to the present; analyses its slow growth and stagnation; recommends the use of multipurpose cadastre which would integrate title, engineering and other detailed surveys and, finally, warns that no gains are likely to be registered unless the Indian Universities and the Polytechnics are encouraged to set up survey degree and diploma courses respec...