120 research outputs found

    Management of drought crisis in semnan province

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    Semnan province has over than 95000 km of space has been sixth province of Iran, which because of skeptical geographical conditions have different climate diversity. Adjacency to centre) dessert and its consequences and problems in side southern part of province on the one hard and adjacency to forest area of Mazandaran & Golestan realm in north margin of province on the other hand, have resulted in diversity of climate and realm so forth multiplicity and differentiation of metric incidences specially flood, storm, hail, drought and frostbite: - Lower's of longtime raining average of province (140 mm in a year) comparing to country and universal average causes permanent dominant dangers which requires risk drought management in special condition. Considering statistics and information, it has been understood mat most damages received from natural incidents of province are related to atmospheric calamities (drought, flood, hail, frost bite & etc) which have surpassed considerable parts of public installation and buildings, roads, residential and commercial places and domestic productive parts and vast damages remain. Done surveys present although plurality of flood and its related phenomenon such as storm, lightning and hail occurrence is much more in province but from economic point of view the most received damages are related to occurrence and lasting of drought and its direct wide influences and damages. So, flood and frostbite damages come in lat step. Applying appropriate management in natural and economical sources and crises management slung with correct programming in best us of limited existent sources in province and preventing actions in hard were section (physical measures related to performance of development projects and plans) and in software section (management, studies and action, etc) have an important role in prevention of occurrence and reduction of probable accidents damages. In this research with a managerial point of view we deal with Processes of damages arising from occurrence of several main factors of natural incidents which have the most multiplicity of happening and damages and by comparing to spent credits for compensation of resulted damages, an analyze of province incidence is presented and at last by using made inspects results and answered inquiries by managers and natural & probable incidents specialists, announced points of view are classified and appropriate solution & recommendations for prevention of natural incidents happening reduction of their damages are presente

    Fibre electronics: towards scaled-up manufacturing of integrated e-textile systems

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    The quest for a close human interaction with electronic devices for healthcare, safety, energy and security has driven giant leaps in portable and wearable technologies in recent years. Electronic textiles (e-textiles) are emerging as key enablers of wearable devices. Unlike conventional heavy, rigid, and hard-to-wear gadgets, e-textiles can lead to lightweight, flexible, soft, and breathable devices, which can be worn like everyday clothes. A new generation of fibre-based electronics is emerging which can be made into wearable e-textiles. A suite of start-of-the-art functional materials have been used to develop novel fibre-based devices (FBDs), which have shown excellent potential in creating wearable e-textiles. Recent research in this area has led to the development of fibre-based electronic, optoelectronic, energy harvesting, energy storage, and sensing devices, which have also been integrated into multifunctional e-textile systems. Here we review the key technological advancements in FBDs and provide an updated critical evaluation of the status of the research in this field. Focusing on various aspects of materials development, device fabrication, fibre processing, textile integration, and scaled-up manufacturing we discuss current limitations and present an outlook on how to address the future development of this field. The critical analysis of key challenges and existing opportunities in fibre electronics aims to define a roadmap for future applications in this area

    A New Frequency-Luminosity Relation for Long GRBs?

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    We have studied power density spectra (PDS) of 206 long Gamma-Ray Bursts (GRBs). We fitted the PDS with a simple power-law and extracted the exponent of the power-law (alpha) and the noise-crossing threshold frequency (f_th). We find that the distribution of the extracted alpha peaks around -1.4 and that of f_th around 1 Hz. In addition, based on a sub-set of 58 bursts with known redshifts, we show that the redshift-corrected threshold frequency is positively correlated with the isotropic peak luminosity. The correlation coefficient is 0.57 +/- 0.03.Comment: 9 pages, 17 figures, 1 table; Accepted for publication in MNRA

    The Hurst Exponent of Fermi GRBs

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    Using a wavelet decomposition technique, we have extracted the Hurst exponent for a sample of 46 long and 22 short Gamma-ray bursts (GRBs) detected by the Gamma-ray Burst Monitor (GBM) aboard the Fermi satellite. This exponent is a scaling parameter that provides a measure of long-range behavior in a time series. The mean Hurst exponent for the short GRBs is significantly smaller than that for the long GRBs. The separation may serve as an unbiased criterion for distinguishing short and long GRBs.Comment: Accepted for publication in Monthly Notices of the Royal Astronomical Societ

    Spectral Lags of Gamma-Ray Bursts from Primordial Black Hole (PBH) Evaporations

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    Primordial Black Holes (PBHs), which may have been created in the early Universe, are predicted to be detectable by their Hawking radiation. PBHs with an initial mass of 5.0 * 10^14 g should be expiring today with a burst of high energy particles. Evaporating PBHs in the solar neighborhood are candidate Gamma-Ray Bursts (GRBs) progenitors. We propose spectral lag, which is the temporal delay between the high energy photon pulse and the low energy photon pulse, as a possible method to detect PBH evaporation events with the Fermi Gamma-ray Space Telescope Observatory.Comment: 3 pages; Published in the proceedings of Huntsville 2008 symposium on GRBs; Indices in Equation 7 and 8 correcte

    The Minimum Variability Time Scale and its Relation to Pulse Profiles of Fermi GRBs

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    We present a direct link between the minimum variability time scales extracted through a wavelet decomposition and the rise times of the shortest pulses extracted via fits of 34 Fermi GBM GRB light curves comprised of 379 pulses. Pulses used in this study were fitted with log-normal functions whereas the wavelet technique used employs a multiresolution analysis that does not rely on identifying distinct pulses. By applying a corrective filter to published data fitted with pulses we demonstrate agreement between these two independent techniques and offer a method for distinguishing signal from noise.Comment: Accepted for publication in MNRAS Letters. 4 pages, 4 figure

    Microscopic calculation of 6Li elastic and transition form factors

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    Variational Monte Carlo wave functions, obtained from a realistic Hamiltonian consisting of the Argonne v18 two-nucleon and Urbana-IX three-nucleon interactions, are used to calculate the 6Li ground-state longitudinal and transverse form factors as well as transition form factors to the first four excited states. The charge and current operators include one- and two-body components, leading terms of which are constructed consistently with the two-nucleon interaction. The calculated form factors and radiative widths are in good agreement with available experimental data.Comment: 9 pages, 2 figures, REVTeX, submitted to Physical Review Letters, with updated introduction and reference

    FASTKIT: A Mobile Cable-Driven Parallel Robot for Logistics

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    International audienceThe subject of this paper is about the design, modeling, control and performance evaluation of a low cost and versatile robotic solution for logistics. The robot under study, named FASTKIT, is obtained from a combination of mobile robots and a Cable-Driven Parallel Robot (CDPR). FASTKIT addresses an industrial need for fast picking and kitting operations in existing storage facilities while being easy to install, keeping existing infrastructures and covering large areas. The FASTKIT prototype consists of two mobile bases that carry the exit points of the CDPR. The system can navigate autonomously to the area of interest. Once the desired position is attained, the system deploys the CDPR in such a way that its workspace corresponds to the current task specification. The system calculates the required mobile base position from the desired workspace and ensures the controllability of the platform during the deployment. Once the system is successfully deployed, the set of stabilizers are used to ensure the prototype structural stability. Then the prototype gripper is moved accurately by the CDPR at high velocity over a large area by controlling the cable tension
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