Detecting Flow Anomalies in Distributed Systems

Deep within the networks of distributed systems, one often finds anomalies that affect their efficiency and performance. These anomalies are difficult to detect because the distributed systems may not have sufficient sensors to monitor the flow of traffic within the interconnected nodes of the networks. Without early detection and making corrections, these anomalies may aggravate over time and could possibly cause disastrous outcomes in the system in the unforeseeable future. Using only coarse-grained information from the two end points of network flows, we propose a network transmission model and a localization algorithm, to detect the location of anomalies and rank them using a proposed metric within distributed systems. We evaluate our approach on passengers' records of an urbanized city's public transportation system and correlate our findings with passengers' postings on social media microblogs. Our experiments show that the metric derived using our localization algorithm gives a better ranking of anomalies as compared to standard deviation measures from statistical models. Our case studies also demonstrate that transportation events reported in social media microblogs matches the locations of our detect anomalies, suggesting that our algorithm performs well in locating the anomalies within distributed systems

Investigation to enhance sustainable improvements in high speed rail transport

Transport systems are essential for the life of modern societies and economies. A sustainable transport system can shape a sustainable development pattern and socio-economic attributes of urban centres and regions. The use of private cars and trucks is increasing in most countries, creating more congestion, accidents, pollution and energy consumption. Many governments desire to achieve growth in public transport to overcome these adverse trends. A massive shift toward an environmentally sound type of transport is crucial and railways are deemed to be one of the most sustainable modes. All over the world the railway industry is involved in a renewal to reform and up-date rail, prompted largely by environmental concerns. The trend is to develop speed-competitive systems to expand transportation capacity. The focus of the current research, which is at its commencing stages, is to investigate the opportunities to apply an alternative approach to railway operations to overcome the difficulty of high speed transport in servicing larger amounts of demand, while achieving minimum point to point travel time, in a viable and integrated environment for both passenger and freight services. The expected outcome of the research project is to present a framework that may be used to identify and evaluate the most cost-effective transport solution to service not only major cities, but also regional centres along an interregional rail corridor, thus providing greater benefits on local economies and to build a spine for future development

Using natural means to reduce surface transport noise during propagation outdoors

This paper reviews ways of reducing surface transport noise by natural means. The noise abatement solutions of interest can be easily (visually) incorporated in the landscape or help with greening the (sub)urban environment. They include vegetated surfaces (applied to faces or tops of noise walls and on building façades and roofs ), caged piles of stones (gabions), vegetation belts (tree belts, shrub zones and hedges), earth berms and various ways of exploiting ground-surface-related effects. The ideas presented in this overview have been tested in the laboratory and/or numerically evaluated in order to assess or enhance the noise abatement they could provide. Some in-situ experiments are discussed as well. When well-designed, such natural devices have the potential to abate surface transport noise, possibly by complementing and sometimes improving common (non-green) noise reducing devices or measures. Their applicability strongly depends on the available space reserved for the noise abatement and the receiver position

Fiber-optic interferometric sensor for monitoring automobile and rail traffic

This article describes a fiber-optic interferometric sensor and measuring scheme including input-output components for traffic density monitoring. The proposed measuring system is based on the interference in optical fibers. The sensor, based on the Mach-Zehnder interferometer, is constructed to detect vibration and acoustic responses caused by vehicles moving around the sensor. The presented solution is based on the use of single-mode optical fibers (G.652.D and G.653) with wavelength of 1550 nm and laser source with output power of 1 mW. The benefit of this solution lies in electromagnetic interference immunity and simple implementation because the sensor does not need to be installed destructively into the roadway and railroad tracks. The measuring system was tested in real traffic and is characterized by detection success of 99.27% in the case of automotive traffic and 100% in the case of rail traffic.Web of Science2662995298