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We perform a numerical experiment to investigate how the surface reverberation spectrum changes with the intensity of the surface waves. We focus on the sound in the middle frequency range of 1 to 5 kHz, the scattering of which depends significantly on the state of the sea surface and may not be resonant. The novelty of this work is that we use an accurate diffraction model and a surface wave model that takes into account the nonlinear interaction between the surface harmonics.

We propose a proxy signcryption scheme for a multi-party setting, resistant to randomness leakage and setup attacks. Our scheme is an alternative to typical constructions, based on a double Schnorr signature approach, where the linear combination of long term secrets and ephemeral random values occurs both at the initiator and proxy nodes. Our scheme is provably secure in a new stronger model, where the adversary can control the randomness of both parties. Moreover, our proposition is well suited for networks of many independent and moving nodes; especially modern railway infrastructure and vehicle-to-vehicle/infrastructure (V2X) environments, where a broad range of devices with potentially weak computational power and inadequate randomness, is used. Early benchmarks and performance analysis from our proof of concept implementation, suggest that nodes, which use regular Schnorr based schemes, could be successfully upgraded to our more secure alternative construction. Collected timings are still at the acceptable level, proving the applicability of our scheme in modern railway and V2X environments.

We consider the scattering of a plane sound wave at a rough water-air interface using numerical simulations. We describe our method in detail and demonstrate its functionality with simple examples. The main advantage of the method is that there are no limitations on the relation between the shape of the surface and the incident wave. This allows us to consider large Rayleigh parameters, shading, and multiple scattering. In the method, the solution of the Helmholtz equation in the form of an integral over the domain boundary is used only in the inner domain. In the outer domain, separation of variables is used to obtain a non-local integral boundary condition on an artificial boundary.

This paper presents the designs of two digital circuits in which processing of data (stored in volatile and non-volatile memories) is locally performed and routed; these circuits are referred to as data-centric and therefore, amenable to Near-Memory (NM)operation. Two circuits are proposed; they utilize at logic level a 2-2AOI gate, but with different types of selector. Simulation results using HSPICE are provided for logic data path and memory access performance. Comparison between designs with either a Programmable Metallization Cell (PMC), or a Phase Change Memory (PCM), is assessed; simulation confirms that in most cases of memory operations, a PMC based data-centric circuit has better performance than a PCM-based circuit in terms of delay. The proposed data-centric circuits are evaluated also for implementation of more complex functional blocks (such as adders and encoder) as well as a balanced FIFO merger for sorting application.

Large sparse linear system of equations arise in many areas of science and engineering. Although, there are several black-box general sparse solvers, usually they are not as effective as domain specific solvers. In addition, most solvers contain multiple choices during the solution process which can be tailored to a specific domain. A natural first step towards a black-box solver that is as effective as domain specific solvers is to come up with a technique to identify the application domain of the problem. In this work, we propose to use some computationally inexpensive matrix properties for the classification task, and apply several classifiers to identify the application domain. Experiments on a large set of sparse matrices show that the domain information is predicted with 75.9% overall accuracy, and matrices in a specific domain can be predicted with 99% accuracy.

Taking pulse is a basic skill for medical examination that requires specialized training. Using high-fidelity human simulation mannequin or real specimen may not be appropriated. In this paper, we have developed a pulse simulation to support medical education and training for nursing and medical students. In order to achieve realistic experience, we have integrated Augmented Reality (AR) technology, haptic device and physical medical training tool that respond with force feedback in virtual pulse simulation. The system will support “finger touch” on low cost medical training mannequins. The pulse simulation was programmed to give pulse rate between 40–160 beats per minute (bpm.) using Phantom Omni, which can generate a force for virtual pulses in a range between 0–1 newton (N.) This set up was applied to the low cost medical training mannequins with the help of AR technology to make realistic presentations. The evaluation of the system was carried out in terms of usability satisfaction, cost and performance. The results gave positive results in all categories and the proposed system has the potential to replace hi-tech costly medical training mannequins for pulse measurement training.

This paper presents a simulation-based analysis of spike and flicker noise in a Phase Change Memory (PCM); this investigation is based on HSPICE simulation by taking into account cell-level (with its neighbors) and array-level considerations. State switching phenomena in binary PCM memories are dealt in detail to assess the impact of these two types of noise. It is shown that a lower feature size is of concern for flicker noise in terms of value and percentage variation (while not substantially affecting array-level performance). This paper also shows that spike noise has a radically different behavior: spike noise shows a dependency on the PCM resistance more than the type of state of the PCM. It increases substantially when the amorphous resistance increases and has a nearly constant value when the memory cell is changing to an amorphous state

We report on the generation of wide Raman combs with over-five octaves bandwidth from the UV at 300 nm to the long-wavelength infrared at 12.5 µm. These combs are generated via transient stimulated Raman scattering in H 2 -filled inhibited coupling (IC) Kagome Hollow-Core Photonic Crystal Fiber pumped with high power picosecond fiber laser with several spectral lines and with an output average power of up to ∼10 W. We demonstrate that by selective generation of Raman line that the current set-up can be used to develop high power fiber lasers at non-conventional wavelength outside the bandwidth emissions of the rare earth. As an example, we generated laser emission at 1.8 µm with average power as high as 9.3 W, corresponding to a quantum efficiency of 75%.

This research is aimed at providing more reliable predictions of the characteristics of reverberation as a function of frequency and range, as well as propagation path and wind wave characteristics. A theoretical model is derived and is compared to experimental results which consist of simultaneous acoustic and wind wave characteristics measurements.

A large number of solutions on electrostimulation were proposed in the last twenty years with the aim of looking after certain pathologies. They rely on the principle that electrostimulation of a neuron, muscle or another internal nerve is possible. In this context, this paper presents a solution of deep brain stimulator (DBS) having for aim to reduce the influence of the Parkinson's disease. This paper presents monophasic and biphasic electrostimulation topologies. The integrated system on chip solution was developped on 0.35?m standard CMOS technology. The silicon die possesses a size of 620x550?m2, with an improved battery life of about a week (ten times longer than the discrete version). The circuit has two terminals directly connected on the brain via two electrodes and two terminals to be connected to the coin cell battery (the only non under cutaneous part).

This paper introduces interactive query expansion for Thai library automation system. The approach aims to expand original Thai-language user queries to a new set of more meaningful queries in the same language. The purpose is to improve the quality of Thai user query and suggest the user with a new set of more meaningful queries. User satisfaction with retrieved results should be improved. The approach employs the information in MARC 21 bibliographic format (title access field 245) in order to generate a new list of candidate terms. The genetic process is then augmented to select new expanded terms from those candidates. The approach is evaluated on the collection of Thai educational materials such as book, journal and magazine. The performance is measured by the accuracy of new expanded terms. We asked 87 participants whether our generated terms are related to their original query. The experiment shows that users quite agree that our technique is able to generate useful terms for searching their materials in library system.

There is an increasing need for narrow linewidth, high average power ultraviolet (UV) laser sources for high resolution spectroscopy, remote environmental sensing, laser-induced fluorescence, semiconductor inspection, and LIDAR applications [1,2]. A way to design efficient sources in the UV is to frequency convert diode-pumped solid-state lasers that emit in the near infrared (IR) [3]. In this case, obtaining high nonlinear conversion efficiency requires a large peak power in the fundamental wave. At a fixed repetition rate and average power, this results in a tradeoff between attainable linewidth, related to the pulse duration, and the nonlinear conversion efficiency.

Sample water was collected from the open wells around the KMML area. Then the main physiochemical and biological analysis of the parameters like colour, conductivity, salinity, turbidity, pH, BOD, COD, TDS, iron, nitrates, Fecal coliforms etc. were done. After selecting some important water quality parameters, the calculation of Water Quality Index (WQI) was done. Finally, the water quality mapping using GIS was done. All the well water was found unsuitable for domestic purpose as it confirmed by WQI. Hence the use of waters of open wells in and around the industrial area may cause health hazards to nearby inhabitants. So it is necessary to control the contaminant transportation and ground water pollution in and around KMML area.

This paper presents a numerical method to compute the radiation pattern of an antenna placed behind a radome, which is a body of revolution (BOR). The method is based on boundary element methods (BEM): a free-standing antenna is calculated by a domain decomposition technique and appears as an excitation term of a free-standing radome problem, which is treated by a BEM specific to BOR.

We report on a picosecond laser system that can run from single shot to 50MHz, with energies up to 100µJ.

Several industrial applications require highly reliable and efficient laser systems delivering high average power in the modelocking regime. For this purpose, the frequency feedback laser architecture which is based on doped fibers and acousto-optic modulator has numerous advantageous compared to passive ML with SESAM.

High power harmonic generation of visible (green) and UV light have been dominated mainly by solid-state lasers but, in recent years, fiber laser based systems have started to challenge them [1]. In most applications, high peak and pulse energies are typically required. Nonlinearities need, therefore, to be minimized and the actual trend is to use large mode area fibers with very large core sizes [2, 3]. Such solution typically requires a master oscillator power amplifier architecture in order to achieve enough average output power or pulse energy without compromising the stability and the quality of the output beam.

This paper presents a numerical method developed in order to compute the performances of antenna arrays taken into account coupling between radiating elements and edge effects. This method is based on domain decomposition techniques applied to boundary element solver.

This article proposes two prototypes in order to assure chronic deep brain stimulation in freely moving rodents, modeling the functional neurosurgical approach developed for the treatment of Parkinson's disease, which is now extending to a number of neurological and psychiatric diseases. This treatment is based on electrical simulation in a precise brain target with adapted parameters for each indication in terms of frequency, intensity and pulse width. The first topology, a discrete solution has been realized by using CMS technology and tested on a rat model of Parkinson's disease. The second one, even more miniaturized for a mouse application, is an all integrated solution with live tuning. A 0.35µm standard CMOS technology has been used for the realization of this last one solution with a final silicon ar ea of 620 ⋆ 516, 4µm2.

Web usage mining has become popular in various business areas related with Web site development. In Web usage mining, commonly visited navigational paths are extracted in terms of Web page addresses from the Web server visit logs, and the patterns are used in various applications including recommendation. The semantic information of the Web page contents is generally not included in Web usage mining. In this work, a framework for integrating semantic information with Web usage mining is presented. The frequent navigational patterns are extracted in the form of ontology instances instead of Web page addresses and the result is used for generating Web page recommendations to the visitor. In addition, an evaluation mechanism is implemented in order to test the success of the recommendation. Test results show that more accurate recommendations can be obtained by including semantic information in the Web usage mining.

Recently, micropattern detectors and in particular micromegas are receiving much attention from the community of rare event searches. The main features that make these detectors rather promising for this field of research and which distinguish them from other gaseous structures are their very stable operation, their homogeneity and granularity which result in very good energy and spatial resolution. In this paper we summarize the latest results on the development of new generation micromegas detectors focusing on rare event searches; more specifically their performance in the search of axions and their possible application to double beta decay experiments.

The optimum seed pulse-profile for a desired output pulse-profile in saturated ns-pulsed fiber-amplifiers is determined with an analytical solution for the amplification process. It can be regarded as an inverse Frantz-Nodvik-equation for the seed photon-density.

We study the temporal behaviour of photodarkening in an Yb-doped large-mode-area (LMA) fiber and show photobleaching of the same fiber. The absorption spectra and the influence on the lasing properties when this fiber is used in a CW laser oscillator.

We study the limitation in energy storage of LMA Yb-doped fibers and show the importance of the gain recovery time for high power nanosecond laser and amplifier design.

We report on a Q-switched fiber laser producing pulse durations well below 10 ns by using a short-length ytterbium-doped rod-type photonic crystal fiber as gain medium.