On the particle paths and the stagnation points in small-amplitude deep-water waves

In order to obtain quite precise information about the shape of the particle paths below small-amplitude gravity waves travelling on irrotational deep water, analytic solutions of the nonlinear differential equation system describing the particle motion are provided. All these solutions are not closed curves. Some particle trajectories are peakon-like, others can be expressed with the aid of the Jacobi elliptic functions or with the aid of the hyperelliptic functions. Remarks on the stagnation points of the small-amplitude irrotational deep-water waves are also made.Comment: to appear in J. Math. Fluid Mech. arXiv admin note: text overlap with arXiv:1106.382

Modulational instability of electromagnetic-spin waves in microstrip line on substrate of ferrite-dielectric

The solitonic regimes of signal's propagation in nonlinear waveguides are of practical interest from the point of view of creating communication systems with high speed of information transmission, that are resistant to interference. The active investigation of nonlinear waves takes place in the physics of magnetic phenomena. The waves in magnetic media are characterized by wide possibilities of dispersion varying. That allows us to provide the existance of the particular domains of the dispersion curves where the conditions of the modulational instability's (MI) observation are satisfied.In the present work the results of the nonlinear effects' experimental observation in the microstrip line on the substrate of ferrite-dielectric magnetized parallel, along the strip, are discussed. Those effects take place in the domain near the lower frequency of the bandstop and are interpreted in the work as MI of the electromagnetic wave in the line. The MI phenomenon observation is significantly connected with the decay effects [9]

A Study of the Stability Characteristics of the Intelligent Robotic Vehicle Movement

Unmanned vehicles have been developed at a rapid pace worldwide. However, despite the significant sophistication of these technologies, there arises a broad list of problems related to the IRV (intelligent robotic vehicle) movement. One of the most important problems is to ensure the stability characteristics of the IRV movement. To this end, we developed a methodology for calculating the angular parameters, the radius of the trajectory curvature, and the coordinates of the IRV position during its movement. We created a 3-D model of the IRV, which allowed us to provide the most complete insight into its movement, placement of new sensors, monitoring, and calibration. The experimental studies have shown that the minimum deviation of the trajectory is observed at the IRV movement speed of 7 km/h

Recent advances in smart monitoring of historic structures

This paper presents the project SMooHS, Smart Monitoring of Historic Structures, which brings together scientists from 7 countries working to establish a competitive and simple to use monitoring technique based on wireless sensors. The proposal aims to deliver novel structural health monitoring (SHM) systems capable of taking advantage of the reduction of wiring costs and at the same time achieving a further cost reduction by e.g. not relying on a centralized communication gateway architecture. Such novel approaches would deliver a “place-and-forget” SHM solution. Although the market offers a large number of different sensors their applicability for long-term monitoring of cultural heritage has not been validated in detail. Especially the long term stability and the reliability of the measured data might be problematic. In order to provide the practitioner in the field of cultural heritage with a tool which goes beyond the mere accumulation of data, but instead provides help in the sense of warnings and recommendations for action, data fusion and interpretation is implemented within the monitoring system. Three main case studies (located in Berlin - Germany, Schwäbisch Gmünd - Germany, and Bologna - Italy) are planned to be used to demonstrate and to validate the work that is done in the core work packages. Three test sites (located in Jarash - Jordan, Hebron - West-Bank, Palestine, and Vienna – Austria) serve for method and system enhancement. The proposed wireless system is user friendly, to be used by practitioners in the field, modular (modules for specific questions arising at the object to be monitored and sensor combinations), open source, for maximum transparency and open for extensions and new modules. The modularity and open source concept are most important for making a dynamic tool, which can be updated and broadened continuously with new research results, both from partners within this project team and from other research groups with their special expertise. However, the system needs to be simple taking also the low budget available in many cases for such a system into account

A health risk assessment for fluoride in Central Europe

Like many elements, fluorine (which generally occurs in nature as fluoride) is beneficial to human health in trace amounts, but can be toxic in excess. The links between low intakes of fluoride and dental protection are well known; however, fluoride is a powerful calcium-seeking element and can interfere with the calcified structure of bones and teeth in the human body at higher concentrations causing dental or skeletal fluorosis. One of the main exposure routes is via drinking water and the World Health Organisation currently sets water quality guidelines for the element. In Central Europe, groundwater resources that exceed the guideline value of 1.5 mg l-1 are widespread and effects on health of high fluoride in water have been reported. The aim of the current project was to develop a geographic information system (GIS) to aid the identification of areas where high-fluoride waters and fluorosis may be a problem; hence, where water treatment technologies should be targeted. The development of the GIS was based upon the collation and digitisation of existing information relevant to fluoride risk in Ukraine, Moldova, Hungary and Slovakia assembled for the first time in a readily accessible form. In addition, geochemistry and health studies to examine in more detail the relationships between high-fluoride drinking waters and health effects in the population were carried out in Moldova and Ukraine demonstrating dental fluorosis prevalence rates of 60–90% in adolescents consuming water containing 2–7 mg l-1 fluoride