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1
Otte, Tanya L., Christopher G. Nolte, Martin J. Otte et Jared H. Bowden. « Does Nudging Squelch the Extremes in Regional Climate Modeling ? » Journal of Climate 25, no 20 (9 mai 2012) : 7046–66. http://dx.doi.org/10.1175/jcli-d-12-00048.1.
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Abstract An important question in regional climate downscaling is whether to constrain (nudge) the interior of the limited-area domain toward the larger-scale driving fields. Prior research has demonstrated that interior nudging can increase the skill of regional climate predictions originating from historical data. However, there is concern that nudging may also inhibit the regional model’s ability to properly develop and simulate mesoscale features, which may reduce the value added from downscaling by altering the representation of local climate extremes. Extreme climate events can result in large economic losses and human casualties, and regional climate downscaling is one method for projecting how climate change scenarios will affect extreme events locally. In this study, the effects of interior nudging are explored on the downscaled simulation of temperature and precipitation extremes. Multidecadal, continuous Weather Research and Forecasting model simulations of the contiguous United States are performed using coarse reanalysis fields as proxies for global climate model fields. The results demonstrate that applying interior nudging improves the accuracy of simulated monthly means, variability, and extremes over the multidecadal period. The results in this case indicate that interior nudging does not inappropriately squelch the prediction of temperature and precipitation extremes and is essential for simulating extreme events that are faithful in space and time to the driving large-scale fields.
2
Han, Yu. « Semi-Parametric Statistical Model for Extreme Value Statistical Models and Application in Automatic Control ». Applied Mechanics and Materials 680 (octobre 2014) : 455–58. http://dx.doi.org/10.4028/www.scientific.net/amm.680.455.
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The frequency that extreme events appear in the life is low,but once it appears,the impact will be significant; many scholars have conducted in depth research and found that statistical theory of extreme value. The theory of extreme statistics plays a more and more important role in many fields such as automatic control, assembly line etc. This paper,makes an in-depth research towards the characteristics and parameter estimation of the extreme value statistical models,as well as the application,mainly analyzes the Bayes parameter estimation method of extreme value distribution,the extreme value distribution theory and Copula function random vector model.
3
Varshney, Rajeev. « Integrated Physiology Extreme Environment ». Defence Life Science Journal 9, no 1 (7 décembre 2023) : 3–4. http://dx.doi.org/10.14429/dlsj.9.19711.
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A successful military operation not only necessitates cutting-edge, contemporary weapon systems but also, fittest men behind these machines. These men, desirably with the highest order of physiological and psychological well-being to operate in the harshest of battle fields shape the battle field dynamics through grit and valour. Defence Institute of Physiology & Allied Sciences (DIPAS, DRDO), a Delhi based DRDO laboratory, has been contributing towards the operational readiness of Indian troops in varied environmental conditions through physiological, biomedical and ergonomic approaches. The translational research in DIPAS has been contributing towards safe induction of troops to high altitude and desert environments, sustenance in extreme environmental conditions and improving soldier performance in demanding operational conditions.
4
Dulière, Valérie, Yongxin Zhang et Eric P. Salathé. « Extreme Precipitation and Temperature over the U.S. Pacific Northwest : A Comparison between Observations, Reanalysis Data, and Regional Models* ». Journal of Climate 24, no 7 (1 avril 2011) : 1950–64. http://dx.doi.org/10.1175/2010jcli3224.1.
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Abstract Extreme precipitation and temperature indices in reanalysis data and regional climate models are compared to station observations. The regional models represent most indices of extreme temperature well. For extreme precipitation, finer grid spacing considerably improves the match to observations. Three regional models, the Weather Research and Forecasting (WRF) at 12- and 36-km grid spacing and the Hadley Centre Regional Model (HadRM) at 25-km grid spacing, are forced with global reanalysis fields over the U.S. Pacific Northwest during 2003–07. The reanalysis data represent the timing of rain-bearing storms over the Pacific Northwest well; however, the reanalysis has the worst performance at simulating both extreme precipitation indices and extreme temperature indices when compared to the WRF and HadRM simulations. These results suggest that the reanalysis data and, by extension, global climate model simulations are not sufficient for examining local extreme precipitations and temperatures owing to their coarse resolutions. Nevertheless, the large-scale forcing is adequately represented by the reanalysis so that regional models may simulate the terrain interactions and mesoscale processes that generate the observed local extremes and frequencies of extreme temperature and precipitation.
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Hartono, Inggrit Aulya, Fitroh Aysyatun Hasanah, Amalia Azizah Zain, Firdha Kusuma Ayu Anggraeni, Yushardi Yushardi et Audri Mely Prabandari. « EXTREME LOW FREQUENCY MAGNETIC FIELD RADIATION : EFFECT ON THE PHYSICAL CONDITION OF KETAN TAPE INTENSITY 500 µT ». EduFisika : Jurnal Pendidikan Fisika 8, no 3 (13 décembre 2023) : 363–68. http://dx.doi.org/10.59052/edufisika.v8i3.30210.
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The electromagnetic wave spectrum includes extremely low frequency (ELF) magnetic fields, which have a frequency below 300 Hz and are considered non-radiation radiation. This research examines the effect of ELF magnetic fields on the physical condition of white sticky rice tape food, a traditional fermented food in Indonesia. The research is an experimental study that evaluates the physical condition of food ingredients. The research divides the materials into two groups: the control group, which is not exposed to magnetic fields, and the experimental group, which is exposed to magnetic fields with an intensity of 500 µT. The research uses 20 packs of each ingredient, with 10 packs in each group and 100 gr in each pack. The research tests four modules: login page, teacher’s profile update, image upload, and question creation. The research finds that exposure to an ELF magnetic field affects the aroma and texture of food ingredients. Exposure to ELF magnetic fields can speed up the growth of microorganisms. The research observes that the white sticky rice tape in the experimental group has a softer texture than the control group.
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Nina, Aleksandra, Vladimir Srećković et Milan Radovanović. « Multidisciplinarity in Research of Extreme Solar Energy Influences on Natural Disasters ». Sustainability 11, no 4 (14 février 2019) : 974. http://dx.doi.org/10.3390/su11040974.
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The atmosphere is a very sensitive medium to extraterrestrial forces, most importantly, solar electromagnetic radiation and energetic particle intrusion. This released intense solar activity can cause sudden disturbances in the Earth’s atmosphere and further create ground telecommunication interferences, blackouts, transportation problems, water supply problems, potential health effects, as well as natural disasters, such as forest fires. These extreme events can cause billions of dollars of damage and impact individuals, families, communities, and societies. For this reason, it is of crucial importance to investigate the connections between this extreme activity and natural disasters, and further develop ways to prevent, prepare against, and respond to them. The aim of this special issue is to engage a wide community of scientists to de-fragment broaden and improve our knowledge in this field. We invite researchers from all relevant fields to publish their recent investigations in this special issue.
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Taleyarkhan, Rusi P. « Monitoring Neutron Radiation in Extreme Gamma/X-Ray Radiation Fields ». Sensors 20, no 3 (23 janvier 2020) : 640. http://dx.doi.org/10.3390/s20030640.
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The monitoring of neutron radiation in extreme high ≈1014 (#/cm2-s) neutron/photon fields and at extremely-low (≈10−3 #/cm2-s) levels poses daunting challenges—important in fields spanning nuclear energy, special nuclear material processing/security, nuclear medicine (e.g., photon-based cancer therapy), and high energy (e.g., dark-matter) research. Variably proportioned (neutron, gammas, X-ray) radiation, spanning 10−2–109 eV in energy, is omnipresent from ultra-low (Bq) activity levels (e.g., cosmic rays/ bananas), to extreme high (>1020 Bq) levels. E.g., in nuclear reactor cores; in spent nuclear fuel bearing nuclear-explosive-relevant safeguard-sensitive isotopes, such as Pu-239; and in cancer therapy accelerators. The corresponding high to low radiation dose range spans a daunting 1016:1 spread—alongside ancillary challenges such as high temperatures, pressure, and humidity. Commonly used neutron sensors get readily saturated even in modest (<1 R/h) photon fields; importantly, they are unable to decipher trace neutron radiation relative to 1014 times greater gamma radiation. This paper focuses on sensing ultra-low to high neutron radiation in extremely high photon (gamma-X ray) backgrounds. It summarizes the state-of-art compared to the novel tensioned metastable fluid detector (TMFD) sensor technology, which offers physics-based 100% gamma-blind, high (60–95%) intrinsic efficiency for neutron-alpha-fission detection, even under extreme (≈103 R/h) gamma radiation.
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Kumar, Pavan, Rajesh Katare et S. B. L. Tripathi. « Tallon's Equation and Its Parameters in Extreme Superconducting Alkali-Halides ». RESEARCH REVIEW International Journal of Multidisciplinary 8, no 10 (13 octobre 2023) : 131–36. http://dx.doi.org/10.31305/rrijm.2023.v08.n10.014.
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In this research paper we have thoroughly investigated that Tallon's Equation and Its Parameters in Extreme Superconducting Alkali-Halides. Superconductivity, a quantum phenomenon characterized by the complete loss of electrical resistance, continues to captivate researchers due to its potential for transformative technological applications. In pursuit of a deeper understanding of superconducting materials, this research explores Tallon's Equation, a critical tool for predicting superconducting properties. Specifically, we investigate the applicability of Tallon's Equation to extreme conditions, particularly high temperatures and pressures, in alkali-halide compounds. This study combines theoretical modeling and experimental validation to assess the accuracy of Tallon's Equation in predicting key parameters of superconducting alkali-halides under extreme environments. We scrutinize alterations in transition temperature, critical magnetic fields, and other pivotal parameters as materials are subjected to high temperature and pressure regimes. Furthermore, this research extends beyond theoretical considerations to practical implications. It explores the potential of Tallon's Equation in guiding the design and development of novel superconducting materials optimized for high-pressure applications. The findings from this study hold promise for advancing our understanding of superconductivity and harnessing it for innovative technologies in fields such as energy transmission, magnetic resonance imaging, and beyond.
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Zampato, L., G. Umgiesser et S. Zecchetto. « Storm surge in the Adriatic Sea : observational and numerical diagnosis of an extreme event ». Advances in Geosciences 7 (19 septembre 2006) : 371–78. http://dx.doi.org/10.5194/adgeo-7-371-2006.
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Abstract. Storm surge events occur in the Adriatic Sea, in particular during autumn and winter, often producing flooding in Venice. Sea levels are forecasted by numerical models, which require wind and pressure fields as input. Their performances depend crucially on the quality of those fields. The storm surge event on 16 November 2002 is analysed and simulated through a finite element hydrodynamic model of the Mediterranean Sea. Several runs were carried out, imposing different atmospheric forcings: wind fields from ECMWF analysis, high resolution winds from the limited area model LAMI and satellite observed winds from QuikSCAT (NASA). The performance of the hydrodynamic model in each case has been quantified. ECMWF fields are effective in reproducing the sea level in the northern Adriatic Sea, if the wind speed is enhanced by a suitable multiplying factor. High resolution winds from LAMI give promising results, permitting an accurate simulation of the sea level maxima. QuikSCAT satellite wind fields produce also encouraging results which claim, however, for further research.
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Rea, Nanda. « Magnetars : neutron stars with huge magnetic storms ». Proceedings of the International Astronomical Union 8, S291 (août 2012) : 11–18. http://dx.doi.org/10.1017/s1743921312023058.
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AbstractAmong the many different classes of stellar objects, neutron stars provide a unique environment where we can test (at the same time) our understanding of matter with extreme density, temperature, and magnetic field. In particular, the properties of matter under the influence of magnetic fields and the role of electromagnetism in physical processes are key areas of research in physics. However, despite decades of research, our limited knowledge on the physics of strong magnetic fields is clear: we only need to note that the strongest steady magnetic field achieved in terrestrial labs is some millions of Gauss, only thousands of times stronger than a common refrigerator magnet. In this general context, I will review here the state of the art of our research on the most magnetic objects in the Universe, a small sample of neutron stars called magnetars. The study of the large high-energy emission, and the flares from these strongly magnetized (~ 1015 Gauss) neutron stars is providing crucial information about the physics involved at these extremes conditions, and favoring us with many unexpected surprises.
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Li, Liang, Guangchun Han et Shunying Ji. « Statistical Analysis of Ice Load on Icebreaker Ship Based on Stochastic Ice Fields ». Journal of Marine Science and Engineering 12, no 3 (1 mars 2024) : 448. http://dx.doi.org/10.3390/jmse12030448.
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Accurately assessing ice loads is a fundamental issue in the field of structural design for ships in ice-covered regions. In this paper, we conducted research on extreme ice load estimation for icebreaking ships, combining stochastic theory with numerical simulation. Firstly, using sea ice data from the Arctic region of the United States National Snow and Ice Data Center, a stochastic ice field model was established under Arctic sea ice conditions using non-parametric estimation and the rejection sampling method, and ice field data were generated stochastically. Then, based on the stochastic ice field data, a three-dimensional numerical model of the interaction between the ice field and the ship hull was established, and the reliability of the numerical model was verified by experimental results. Finally, based on the numerical model of the interaction between the ice field and the ship hull, asymptotic methods were used to study the extreme ice load estimation in different parts of the ship hull, revealing the variation law of the extreme ice load in different parts of the ship hull. This study provides basic theory and technical support for the structural design of ships in polar regions and has engineering application value.
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Yu Hui-Fen, QI He, Tu Xiao-Niu, Zhang Hai-Bo, Chen Da-Li, Wu Jie et Chen Jun. « Research Progress on High-temperature Piezoelectric Vibration Sensors and Piezoelectric Materials ». Acta Physica Sinica 74, no 2 (2025) : 0. https://doi.org/10.7498/aps.74.20240906.
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Vibration sensor technology, particularly piezoelectric vibration sensors, is extensively utilized across various fields due to their excellent dynamic response, linearity, wide bandwidth, high sensitivity, large temperature range, simple structure, and stable performance. They are widely applied in sectors such as nuclear power, aerospace, rail transportation, and defense industries. However, most piezoelectric vibration sensors are limited to operating temperatures below 500 ℃, which restricts their use in extreme high-temperature environments encountered in nuclear reactors, aircraft engines, missile systems, and internal combustion engines. These application scenarios impose higher demands on the reliability of piezoelectric vibration sensors for long-term service in extreme environments. How to improve the operating temperature of piezoelectric vibration sensors to meet the application needs in extreme environments is currently an urgent problem to be solved.<br>High-temperature piezoelectric materials, as the core components of piezoelectric vibration sensors, play a decisive role in determining the overall performance of the sensor. Common high-temperature piezoelectric materials include piezoelectric ceramics and single crystals. To ensure stable operation and excellent sensitivity in extreme environments, it is essential to select piezoelectric materials with high Curie temperatures, high piezoelectric coefficients, high resistivity, and low dielectric losses as the sensing elements of the sensor. Piezoelectric vibration sensors typically come in three main types: bending, compression, and shear. In addition to selecting the appropriate piezoelectric material, it is also crucial to choose the optimal sensor structure tailored to the specific application scenario.<br>Based on the urgent demand for ultrahigh-temperature vibration sensors, this paper primarily reviews the current research progress on high-temperature piezoelectric materials and high-temperature piezoelectric vibration sensors, summarizes the structures, advantages and disadvantages, and application scenarios of different types of high-temperature piezoelectric vibration sensors, explores the current problems and future development trends of high-temperature piezoelectric vibration sensors, and provides ideas for developing the next generation of ultrahigh temperature vibration sensors for extreme environmental applications, which is expected to promote the further development of high-temperature piezoelectric vibration sensing technology.
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Yue, Zongyu, et Haifeng Liu. « Advanced Research on Internal Combustion Engines and Engine Fuels ». Energies 16, no 16 (11 août 2023) : 5940. http://dx.doi.org/10.3390/en16165940.
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Internal combustion (IC) engines serve as power devices that are widely applied in the fields of transport, engineering machinery, stationary power generation, etc., and are evolving towards the goal of higher efficiency and lower environmental impacts. In this Editorial, the role of IC engines for future transport and energy systems is discussed, and research directions for advancing IC engine and fuel technologies are recommended. Finally, we introduce the 14 technical papers collected for this Special Issue, which cover a wide range of research topics, including diesel spray characteristics, combustion technologies for low- and zero-carbon fuels, advanced combustion mode, fuel additive effects, engine operation under extreme conditions and advanced materials and manufacturing processes.
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Lukin, A. N., P. G. Rodimcev et N. B. Eskin. « Monitoring of the geomagnetic field variations at the high- mountain biospheric station «Dzhuga» and forecasting of natural disasters and extreme weather ». Monitoring systems of environment, no 1 (22 mars 2017) : 35–43. http://dx.doi.org/10.33075/2220-5861-2017-1-35-43.
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In the paper realization of the research project connected with monitoring of the Earth magnetic field variations at the high-mountain biosphere station «Dzuga» is considered. The acoustic channel of influence of the space weather and technologies of visualization of the geomagnetic and acoustic fields with use of high-sensitivity model experimental systems is considered. The new concept of forecasting of extreme natural events with use of the universal phenomenon of spacial self-synchronization of oscillations of geomagnetic and acoustic fields and on the basis of the analysis of the structure of holograms of physical fields is formulated.
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Abdillah, Muhammad Imam, et Muhammad Dedi Irawan. « Implementation of the First Come First Served Algorithm in the Futsal Field Booking Application using Extreme Programming ». ZERO : Jurnal Sains, Matematika dan Terapan 7, no 2 (31 décembre 2023) : 182. http://dx.doi.org/10.30829/zero.v7i2.19163.
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<span lang="EN">This research is related to the development of an Android-based futsal field booking application at Laut Dendang Futsal using the First Come First Serve (FCFS) method. Currently, tenants are facing problems with booking futsal fields, especially because the booking process is still manual and time consuming at Laut Dendang Futsal. Ordering systems that do not use information technology cause customers to have to visit the location directly to order the field. The FCFS method is applied to arrange a futsal field booking schedule based on order of arrival, where requests that arrive first will be served first. This research builds an Android-based application with the aim of increasing efficiency in booking management and futsal field scheduling. The development approach used is the Extreme Programming method, which includes planning, design, coding and continuous testing. The results of application development show good performance in minimizing ordering errors and making it easy for Laut Dendang Futsal customers to order fields without having to come directly to the location. Admin can easily manage and record orders, avoiding errors in the ordering system. Thus, this research makes a positive contribution in increasing the efficiency of booking futsal fields, as well as speeding up responses to incidents.</span>
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Malikovna, Nauryzbayeva Rita. « ALGORITHM FOR FINDING EXTREME POINTS OF CERTAIN CURVES ». Journal of Law and Sustainable Development 12, no 12 (6 décembre 2024) : e4192. https://doi.org/10.55908/sdgs.v12i12.4192.
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Objective: Development of an algorithm for studying the extrema of a function in the polar coordinate system and its application for curve analysis. Theoretical Framework: The study of curves was developed on the basis of the general theoretical foundations of mathematics, geometric problems, and tasks from mechanics, physics, natural sciences, and engineering. In the modern world, the study of curves brings significant benefits to many fields, particularly in construction and mechanical engineering. Method: The main methods of research were analysis, synthesis and methods of mathematical analysis of the study using a derivative. Results and Discussion: The research indicates the peculiarities of the concept of extremum in different coordinate systems. The coordinates of the curve point in the Cartesian coordinate system are defined as a function of φ. The extremum of these functions correspond to the extremum of the Cartesian coordinate system of this curve relative to the axis of the abscissa and ordinate. Research implications: The paper presents an algorithm for the method of finding the extreme points of a curve in polar and Cartesian coordinate systems simultaneously. This allows you to find additional points for plotting curves using the analytical method. Originality/Value: The curves are investigated as the functions in the polar system of coordinates.
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Cogato, Alessia, Franco Meggio, Massimiliano De Antoni Migliorati et Francesco Marinello. « Extreme Weather Events in Agriculture : A Systematic Review ». Sustainability 11, no 9 (2 mai 2019) : 2547. http://dx.doi.org/10.3390/su11092547.
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Despite the increase of publications focusing on the consequences of extreme weather events (EWE) for the agricultural sector, a specific review of EWE related to agriculture is missing. This work aimed at assessing the interrelation between EWE and agriculture through a systematic quantitative review of current scientific literature. The review analysed 19 major cropping systems (cereals, legumes, viticulture, horticulture and pastures) across five continents. Documents were extracted from the Scopus database and examined with a text mining tool to appraise the trend of publications across the years, the specific EWE-related issues examined and the research gaps addressed. The results highlighted that food security and economic losses due to the EWE represent a major interest of the scientific community. Implementation of remote sensing and imagery techniques for monitoring and detecting the effects of EWE is still underdeveloped. Large research gaps still lie in the areas concerning the effects of EWE on major cash crops (grapevine and tomato) and the agronomic dynamics of EWE in developing countries. Current knowledge on the physiological dynamics regulating the responses of main crops to EWE appears to be well established, while more research is urgently needed in the fields of mitigation measures and governance systems.
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Mazurek, Paweł A., Aleksander Chudy et Piotr Hołyszko. « Assessment of Electromagnetic Fields in Trolleybuses and Electric Buses : A Study of Municipal Transport Company Lublin’s Fleet ». Energies 17, no 14 (11 juillet 2024) : 3412. http://dx.doi.org/10.3390/en17143412.
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As electromobility and especially the electrification of public transportation develops, it is necessary to safeguard human health and minimize environmental impact. Electromagnetic fields generated by the current flowing through on-board batteries, installations, converters, propulsion, air conditioning, heating, lighting, or wireless communication systems in these vehicles may pose risks to drivers and passengers. This research investigates electromagnetic fields induced by extreme low-frequency currents and permanent magnets on electric and trolleybuses implanted in Lublin, Poland. The identification of electromagnetic fields concerned an electric bus model and two trolleybus models. A comparative analysis of the results obtained with the permissible limits in the environment was carried out.
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Masten, Ann S. « Resilience in children threatened by extreme adversity : Frameworks for research, practice, and translational synergy ». Development and Psychopathology 23, no 2 (18 avril 2011) : 493–506. http://dx.doi.org/10.1017/s0954579411000198.
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AbstractThis article delineates parallel frameworks that grew out of the research on risk and resilience over the past four decades, a framework for research and a framework for practice, and then discusses the promise of an emerging synthesis. The research framework defined the meaning, models, and methods that successfully guided four waves of research to date on the nature and processes involved in human resilience. The applied framework emerged in response to urgent needs of children and families faced by adversity and those charged with helping them, resulting in guidelines for translating the unfolding but incomplete research evidence into action. The application of a resilience approach transformed practice in many fields concerned with promoting resilience in people at risk for problems, revolutionizing the mission, models, measures, and methods of practice to align with the emphasis on positive adaptation and strengths defining a resilience-based approach. Yet these interventions rarely translated back to inform and refine resilience theory in ways that would accelerate progress to promote resilience more effectively. The concluding section on translational synergy discusses the potential for a synthesis of basic and applied resilience frameworks as the next steps toward realizing the original objective and promise of resilience science.
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Miao, Anzhu, et Feiping Liu. « Application of human motion recognition technology in extreme learning machine ». International Journal of Advanced Robotic Systems 18, no 1 (1 janvier 2021) : 172988142098321. http://dx.doi.org/10.1177/1729881420983219.
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Human motion recognition is a branch of computer vision research and is widely used in fields like interactive entertainment. Most research work focuses on human motion recognition methods based on traditional video streams. Traditional RGB video contains rich colors, edges, and other information, but due to complex background, variable illumination, occlusion, viewing angle changes, and other factors, the accuracy of motion recognition algorithms is not high. For the problems, this article puts forward human motion recognition based on extreme learning machine (ELM). ELM uses the randomly calculated implicit network layer parameters for network training, which greatly reduces the time spent on network training and reduces computational complexity. In this article, the interframe difference method is used to detect the motion region, and then, the HOG3D feature descriptor is used for feature extraction. Finally, ELM is used for classification and recognition. The results imply that the method proposed here has achieved good results in human motion recognition.
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Mundell, Carole, et Mark Sullivan. « Workshop on Extreme Physics ». Proceedings of the International Astronomical Union 7, S285 (septembre 2011) : 270. http://dx.doi.org/10.1017/s1743921312000725.
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SummaryNever before has there been such a wealth of versatile ground- and space-based facilities with which to detect variable emission across the electromagnetic spectrum and beyond, to non-EM signals such as neutrinos and gravitational waves, to probe the most extreme phenomena in the Universe. The variable sky is already providing a wealth of new and surprising observations of phenomena such as GRBs, SNe and AGN that are pushing current theories beyond the state of the art. Multi-messenger follow-up will soon become de rigeur, and upcoming radio and optical all-sky transient surveys will revolutionise the study of the transient Universe. In addition to the technical and data challenges presented by such surveys, a major new challenge will be the interpretation of the wealth of available data and the identification of the underlying physics of new classes of variable (and potentially exotic) objects. Theoretical predictions will be vital for interpreting these future transient discoveries.The goal of this workshop was to bring together theorists and observers in order to identify unexplored synergies across three main research areas of extreme physics: gamma-ray bursts, supernovæ and, more generically, relativistic jets. It aimed to discuss key outstanding questions in these rapidly moving fields, such as the composition and acceleration of GRB and AGN jets, GRB progenitors and central engines, the origin of the wide range of observed variability time-scales in GRB prompt and after-glow light curves and related cosmological applications, the physics of the newly-discovered ultra-luminous SN-like optical transients—as well as to speculate on what we might hope to discover with future technology.The workshop absorbed two 90-minute sessions, selecting 3 main science topics (Relativistic Jets, GRBs and SNe) which it organised as structured discussions driven by a series of short but provocative questions. The final session featured a panel-led debate but with full audience participation.
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van de Pol, Martijn, Stéphanie Jenouvrier, Johannes H. C. Cornelissen et Marcel E. Visser. « Behavioural, ecological and evolutionary responses to extreme climatic events : challenges and directions ». Philosophical Transactions of the Royal Society B : Biological Sciences 372, no 1723 (8 mai 2017) : 20160134. http://dx.doi.org/10.1098/rstb.2016.0134.
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More extreme climatic events (ECEs) are among the most prominent consequences of climate change. Despite a long-standing recognition of the importance of ECEs by paleo-ecologists and macro-evolutionary biologists, ECEs have only recently received a strong interest in the wider ecological and evolutionary community. However, as with many rapidly expanding fields, it lacks structure and cohesiveness, which strongly limits scientific progress. Furthermore, due to the descriptive and anecdotal nature of many ECE studies it is still unclear what the most relevant questions and long-term consequences are of ECEs. To improve synthesis, we first discuss ways to define ECEs that facilitate comparison among studies. We then argue that biologists should adhere to more rigorous attribution and mechanistic methods to assess ECE impacts. Subsequently, we discuss conceptual and methodological links with climatology and disturbance-, tipping point- and paleo-ecology. These research fields have close linkages with ECE research, but differ in the identity and/or the relative severity of environmental factors. By summarizing the contributions to this theme issue we draw parallels between behavioural, ecological and evolutionary ECE studies, and suggest that an overarching challenge is that most empirical and theoretical evidence points towards responses being highly idiosyncratic, and thus predictability being low. Finally, we suggest a roadmap based on the proposition that an increased focus on the mechanisms behind the biological response function will be crucial for increased understanding and predictability of the impacts of ECE. This article is part of the themed issue ‘Behavioural, ecological and evolutionary responses to extreme climatic events’.
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Ebeling, Harald. « Which way to the next frontier ? Finding the most powerful cluster lenses ». Proceedings of the International Astronomical Union 11, A29B (août 2015) : 755–57. http://dx.doi.org/10.1017/s1743921316006724.
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AbstractWhile the identification of a worthy topic or challenge is fundamental to the goal of conducting cutting-edge research, another ingredient is indispensable in the field of observational astronomy: the best possible target. Indeed, the ability to choose from a significant number of extremely powerful gravitational lenses was central to the success of the Frontier Fields project. We here briefly review the surveys that provided this crucial pool of targets, before focusing on the results of ongoing work to identify similarly extreme (if not more extreme) systems at higher redshift for the exploration of a yet more distant extragalactic frontier – with JWST and other, evermore ambitious missions.
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Marble, Emily, et Terry Boles. « A Review of the Structural Characteristics of Aerospace Composites ». Science Insights 41, no 7 (31 décembre 2022) : 749–53. http://dx.doi.org/10.15354/si.22.re102.
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Aerospace composite materials’ performance and application level are vital symbols for measuring the advancement and dependability of aerospace models, and they are the key materials enabling the development of aerospace models, which define the performance and success of models. This review summarizes recent significant research advances in the fields of thermal structure, heat protection, thermal wave transmission, heat insulation, and structural composite materials, and proposes new materials for extreme environments, reusable anti-thermal insulation materials, third-generation structural composite materials, and new materials for extreme environments. Low-cost and quick composite component manufacturing is an essential avenue for the future development of aerospace composite materials.
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Yip, King Yau, Kin On Ho, King Yiu Yu, Yang Chen, Wei Zhang, S. Kasahara, Y. Mizukami et al. « Measuring magnetic field texture in correlated electron systems under extreme conditions ». Science 366, no 6471 (12 décembre 2019) : 1355–59. http://dx.doi.org/10.1126/science.aaw4278.
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Pressure is a clean, continuous, and systematic tuning parameter among the competing ground states in strongly correlated electron systems such as superconductivity and magnetism. However, owing to the restricted access to samples enclosed in high-pressure devices, compatible magnetic field sensors with sufficient sensitivity are rare. We used nitrogen vacancy centers in diamond as a spatially resolved vector field sensor for material research under pressure at cryogenic temperatures. Using a single crystal of BaFe2(As0.59P0.41)2 as a benchmark, we extracted the superconducting transition temperature, the local magnetic field profile in the Meissner state, and the critical fields. The method developed in this work offers a distinct tool for probing and understanding a range of quantum many-body systems.
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Lv, Tianyi, Huaming Yu, Liangshi Lin, Yijun Tao et Xin Qi. « Research on Typhoon Prediction by Integrating Numerical Simulation and Deep Learning Methods ». Atmosphere 16, no 1 (20 janvier 2025) : 111. https://doi.org/10.3390/atmos16010111.
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Typhoons rank among the most destructive natural disasters, significantly affecting human activities and daily life. Atmospheric numerical model wind fields, which are widely utilized, often underestimate typhoon intensity. This study proposes a model for predicting typhoon maximum wind speeds using the Long Short-Term Memory (LSTM) neural network. The model predicts maximum wind speeds based on existing atmospheric numerical forecasts, constructs a parametric wind field model from these predictions, and integrates it with the numerical model wind fields to generate an LSTM-optimized wind field. The results show that the LSTM model accurately predicts typhoon maximum wind speeds, with the predicted extreme values closely aligning with actual observations and capturing the trends of maximum wind speed variations. Compared with the ERA5 typhoon maximum wind speed, the C of the LSTM model for predicting the typhoon maximum wind speed is improved from 0.801 to 0.859, and the RMSE and MAE are reduced by 58% and 64%, respectively. In the simulation of Typhoon DELTA (2020), the LSTM-optimized wind field exhibits substantially higher wind speed intensities in the central region of the typhoon compared to the ERA5 wind field, providing a more accurate representation of the intensity and structure of the typhoon.
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Opoku-Ansah, Jerry, Benjamin Anderson, Moses J. Eghan, Peter Osei-Wusu Adueming, Charles L. Y. Amuah et Samuel S. Sackey. « A Retrofitted Metallurgical Microscope Using Light Emitting Diodes for Multi-Spectral Imaging ». Modern Applied Science 11, no 9 (7 août 2017) : 30. http://dx.doi.org/10.5539/mas.v11n9p30.
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Multi-spectral imaging (MSI) has made diagnosis of microscopic samples considerably easier and information abound. Most MSI systems use continuum light sources and filters for imaging purposes. However, these light sources and filters are relatively expensive, unstable due to extreme pressure and temperature and associated with prolong acquisition time. In this work, we present a metallurgical microscope retrofitted with light-emitting diodes (LEDs) as illumination sources for MSI microscopy. This multispectral LED imaging microscope (MSLEDIM) is relatively cheaper and capable of acquiring images in reflection, transmission and scattering modes at thirteen (13) different wavelengths ranging from ultraviolet to near infrared. The microscope has been demonstrated in biomedical and entomological research fields. The MSLEDIM can be used in various scientific research fields for imaging microscopic samples.
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Crow, J. E., D. M. Parkin et N. S. Sullivan. « Materials Science in High Magnetic Fields ». MRS Bulletin 18, no 8 (août 1993) : 17–21. http://dx.doi.org/10.1557/s0883769400037726.
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The recent rapid growth in the emerging areas of magnetic and magnet-related materials research and applications has led to worldwide recognition of the increased importance of research and technology using high magnetic fields. New high-field magnet facilities and major upgrades of existing facilities are being planned and implemented by a number of countries, among them Japan, Germany, France, the Netherlands, Belgium, Great Britain, Poland, Australia, and the United States. Over the next ten years, these developments will advance the state of the art in magnet-related materials science and technologies by a significant quantum jump. Support by many of the national agencies and a strong corporate commitment to stimulate rapid growth in the development of capabilities at higher magnetic fields and in related technologies results in part from an awareness of the impact these technologies will have in developing the new emerging industrial technologies of the 21st century.The Francis Bitter National Magnet Laboratory (FBNML) at the Massachusetts Institute of Technology has been one of the pre-eminent facilities in developing and advancing science and technology in high magnetic fields. The new U.S. National High Magnetic Field Laboratory (NHMFL) at Florida State University, at the University of Florida, and at Los Alamos National Laboratory builds on the success of existing facilities. NHMFL will provide the necessary environment to develop the next generation of high magnetic fields: 30–50-tesla continuous fields, 60-tesla quasi-continuous fields, and pulsed fields from 60–1,000 tesla. The ability to develop broad user capabilities at these extreme fields is crucial for the advancement of the frontiers of science and of magnet-related industries.
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Scholl, Hans Jochen, et Beth Joy Patin. « Resilient information infrastructures ». Transforming Government : People, Process and Policy 8, no 1 (17 mars 2014) : 28–48. http://dx.doi.org/10.1108/tg-12-2012-0015.
Texte intégralRésumé :
Purpose – Disasters of catastrophic scope and scale have occurred more frequently in recent years. Governmental and non-governmental response management has struggled, and affected communities have severely suffered during extreme events. Colossal damage and loss of lives have been inflicted, and the recovery efforts require extended periods of time. In post hoc analyses, actionable information has been found a critical resource requiring resilient information infrastructures (RIIs) that do not break down even under extreme duress. RIIs encompass both tangible and less tangible (for example, social) elements. The purpose of this paper is to pave the way for empirical research on the subject and to conceptually develop a framework for the analysis of information infrastructures and their resiliency, when impacted by catastrophic incidents (also known as extreme events). Design/methodology/approach – The authors review the literatures of disaster research and related fields. They synthesize the literatures from the information perspective and develop a framework of RII. Findings – The synthesis revealed that extreme event-ready RIIs have to be redundant and resourceful both in terms of social, organizational, and knowledge assets as well as in the information and communication technologies. RIIs combine tangible and non-tangible elements, whose interplay is so far incompletely understood. Research limitations/implications – Roles and criticality of RIIs under the impact of an extreme event need to be studied empirically. Practical implications – The study holds the promise to be of great potential utility for responders and recovery managers as well as affected communities in preparedness, response, recovery, and mitigation efforts as timely and actionable information is still the scarcest and most sought resource during a catastrophic incident. Originality/value – Disaster research so far has mostly focused on the technical, organizational, social, and socio-psychological effects of disasters. The authors are adding the information perspective as a unique and distinctive contribution to extreme event research, which connects the tangible elements of information infrastructures with its not so tangible elements, captures their interplay, and analyzes their role and criticality for the resiliency of the information infrastructures when under extreme duress.
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Ardhana, Valian Yoga Pudya. « PENERAPAN METODE EXTREME PROGRAMMING PADA SISTEM INFORMASI PENJUALAN BERBASIS WEB ». Journal of Information Systems Management and Digital Business 1, no 2 (29 janvier 2024) : 227–35. http://dx.doi.org/10.59407/jismdb.v1i2.414.
Texte intégralRésumé :
Along with the development of the industrial revolution 4.0, the need for fast and accurate information is increasing. Sales information systems are needed for business actors operating in various business fields. Especially for business actors whose sales are increasing over time. The increasing number of consumers often becomes an obstacle for business actors in providing product sales services to consumers. This research carried out the development of a sales information system using the extreme programming method approach. The extreme programming approach is able to develop applications relatively quickly and produce applications that suit your needs. This web-based sales information system has the features that business people need to run their business effectively and efficiently. Apart from that, the test results using black-box testing produced a score of 100%, this means that the features contained in the application meet your needs.
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Siao, Hung-Jung, Sue-Huai Gau, Jen-Hwa Kuo, Ming-Guo Li et Chang-Jung Sun. « Bibliometric Analysis of Environmental, Social, and Governance Management Research from 2002 to 2021 ». Sustainability 14, no 23 (2 décembre 2022) : 16121. http://dx.doi.org/10.3390/su142316121.
Texte intégralRésumé :
Extreme weather events caused by climate change have increased people’s focus on sustainability. Environmental, social, and governance management (ESGM) has become crucial for corporate operations and development; ESGM has attracted the attention of the academic communities, and the number of related studies has continued to increase. However, this topic is multidisciplinary and diverse; therefore, this study used the Web of Science Core Collection Database to conduct a bibliometric analysis of ESGM-related articles published from 2002 to 2021. Bibliometrix (R language), VOSviewer, and CiteSpace were used to identify and analyze research trends related to the number of studies, research fields, authors, national institutions, and keywords. The importance of management and governance was identified through keyword analysis; important keywords identified were financial performance, adaptive governance, property rights, sustainable development goals, and corporate governance.
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Chetehouna, Khaled. « Overview of The Forest Fire Research ». Proceeding International Conference on Science and Engineering 3 (30 avril 2020) : xvii. http://dx.doi.org/10.14421/icse.v3.452.
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Tropical forests play a major role in determining the current atmospheric concentration of greenhouse gases. The role of tropical forests is critical because they are carbon-dense with large amount of carbon is stored. With almost 8 million km2 of the humid tropics, the tropical forests are faced to several issues altering their contribution to the carbon cycle, such as deforestation and wildfires. In Europe, extreme wildfires ravaged the European forests in the last years. These situations were extremely dangerous not only for the environment, but also for the socioeconomical point of view because to the proximity of forests from the urban cities or from the agriculture fields. This fact has motivated the European scientific community to explore the wildfires behavior in the purpose to master their expansion, and limit their harmful effect. In this plenary presentation, the French scientific expertise will be exposed with an eye on a possible extrapolation to the tropical forest’s particularity. For this purpose, the following points are going to be discussed: (1) understanding wildfire mechanisms, (2) giving a vision about French scientific experience on forest fires research field, and finally (3) trying to extrapolate these scientific experiences to tropical forests.
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Palamarchuk, Aleksandr, Pavel Yudaev et Evgeniy Chistyakov. « Polymer Concretes Based on Various Resins : Modern Research and Modeling of Mechanical Properties ». Journal of Composites Science 8, no 12 (2 décembre 2024) : 503. https://doi.org/10.3390/jcs8120503.
Texte intégralRésumé :
This review is devoted to experimental studies and modeling in the field of mechanical and physical properties of polymer concretes and polymer-modified concretes. The review analyzes studies carried out over the past two years. The paper examines the properties of polymer concretes based on various polymer resins and presents the advantages and disadvantages of various models developed to predict the mechanical properties of materials. Based on data in the literature, the most promising polymers for use in the field of road surface repair are polymer concretes with poly(meth)acrylic resins. It was found that the most adequate and productive models are the deep machine learning model—using several hidden layers that perform calculations based on input parameters—and the extreme gradient boosting model. In particular, the extreme gradient boosting model showed high R2 values in forecasting (in the range of 0.916–0.981) when predicting damping coefficient and ultimate compressive strength. In turn, among the additives to Portland cement concrete, the most promising are natural polymers, such as mammalian gelatin and cold fish gelatin, and superabsorbent polymers. These additives allow for an improvement in compressive strength of 200% or more. The review may be of interest to engineers specializing in building construction, materials scientists involved in the development and implementation of new materials into production, as well as researchers in the interdisciplinary fields of chemistry and technology.
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Date, Muneyuki. « Recent Progress in High Field Magnetism ». Australian Journal of Physics 48, no 2 (1995) : 187. http://dx.doi.org/10.1071/ph950187.
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Recent progress in high field magnetism performed mainly in the Research Centre for Extreme Materials, Osaka University, is reported, with a short survey of the Centre's history. The main activities are in the fields of magnetism and superconductivity where a common keyword is highly correlated electron physics. A rich variety of effects such as metamagnetism, field-induced electronic transitions etc. is summarised. High field studies are also effective in the fields of atomic and molecular sciences; for example, field-induced transparency in liquid oxygen, and diamagnetic orientation of organic and biological materials. New frontiers in high field technologies are discussed, including a highly sensitive magnetometer using the dynamical Faraday effect.
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Tedesco, M., M. Serreze et X. Fettweis. « Diagnosing the extreme surface melt event over southwestern Greenland in 2007 ». Cryosphere Discussions 2, no 3 (29 mai 2008) : 383–97. http://dx.doi.org/10.5194/tcd-2-383-2008.
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Abstract. Analysis of passive microwave brightness temperatures from the space-borne Special Sensor Microwave Imager (SSM/I) documents a record surface snowmelt over high elevations (above 2000 m) of the Greenland ice sheet during summer of 2007. To interpret this record, results from the SSM/I are examined in conjunction with fields from the National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis and output from a regional climate model. The record surface melt reflects unusually warm conditions, seen in positive summertime anomalies of surface air temperatures, downwelling longwave radiation, 1000–500 hPa atmospheric thickness, and the net surface energy flux, linked in turn to southerly airflow over the ice sheet. Low snow accumulation may have contributed to the record through promoting anomalously low surface albedo.
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Tedesco, M., M. Serreze et X. Fettweis. « Diagnosing the extreme surface melt event over southwestern Greenland in 2007 ». Cryosphere 2, no 2 (19 novembre 2008) : 159–66. http://dx.doi.org/10.5194/tc-2-159-2008.
Texte intégralRésumé :
Abstract. Analysis of passive microwave brightness temperatures from the space-borne Special Sensor Microwave Imager (SSM/I) documents a record surface snowmelt over high elevations (above 2000 m) of the Greenland ice sheet during summer of 2007. To interpret this record, results from the SSM/I are examined in conjunction with fields from the National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis and output from a regional climate model. The record surface melt reflects unusually warm conditions, seen in positive summertime anomalies of surface air temperatures, downwelling longwave radiation, 1000–500 hPa atmospheric thickness, and the net surface energy flux, linked in turn to southerly airflow over the ice sheet. Low snow accumulation may have contributed to the record through promoting anomalously low surface albedo.
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Khazanov, Efim A. « The research programme 'Extreme Light Fields and Their Applications' (2012 – 2014) of the Presidium of the Russian Academy of Sciences ». Quantum Electronics 43, no 3 (31 mars 2013) : 189. http://dx.doi.org/10.1070/qe2013v043n03abeh015172.
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Olšovcová, Veronika, Iva Ambrožová, Anna Cimmino, Dávid Horváth, Benoit Lefebvre, Ondřej Ploc, Vojtěch Stránský, Roman Truneček et Roberto Versaci. « Neutron dose assessment in laser-generated ultra-short pulsed fields ». Radiation Protection Dosimetry 199, no 15-16 (octobre 2023) : 1910–16. http://dx.doi.org/10.1093/rpd/ncac221.
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Abstract ELI Beamlines is one of the pillars of the Extreme Light Infrastructure European Research Infrastructure Consortium (ELI ERIC), the European project aiming at building the next generation of high power lasers for fundamental research and industrial applications. Several high-power lasers are hosted by the ELI Beamlines facility. Even at a power lower than the nominal one, when interacting with a target, the laser can generate mixed ionizing radiation fields of unique nature. One of the major laser systems, High-repetition-rate advanced petawatt laser system (HAPLS) was already used in commissioning experiments. Detecting the neutrons generated during these experiments has been a challenging task, since certain difficulties were faced. First, the experimental conditions were frequently altered during the commissioning phase (such as laser beam parameters, experimental geometry or target type). Next, the extremely short duration of the ionizing radiation pulse generated by the laser (~10−14 s) complicated the correct interpretation of the data provided by the detectors designed and calibrated in standard fields. Here, one commissioning experiment is described, together with the means of addressing the problem of the detection of the ionizing radiation and the lessons learned in this endeavour.
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Al’tshuler, L. V., R. I. Il’kaev et V. E. Fortov. « Use of powerful shock and detonation waves to study extreme states of matter* ». Physics-Uspekhi 64, no 11 (1 février 2022) : 1167–79. http://dx.doi.org/10.3367/ufne.2021.09.039092.
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Abstract This article is written on the basis of a report given 10 January 2003 at the International Scientific Conference, The Nuclear Age: Science and Society, dedicated to the 100th anniversary of the birth of Igor’Vasil’evich Kurchatov. It presents the results of work on the experimental study of substance properties under high pressure shock waves, briefly describes the use of super-strong magnetic fields for the study of substances at high pressure, presents the results of computational and theoretical research methods, and presents some results of studies of substance properties using liner systems in high-power pulsed electrophysical facilities (VNIIEF disk explosion-magnetic generators and USA Pegasus and ATLAS capacitor banks).
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Ibrahim, Riza Adrian, Sukono Sukono et Riaman Riaman. « Estimation of the Extreme Distribution Model of Economic Losses Due to Outbreaks Using the POT Method with Newton Raphson Iteration ». International Journal of Quantitative Research and Modeling 2, no 1 (5 mars 2021) : 37–45. http://dx.doi.org/10.46336/ijqrm.v2i1.118.
Texte intégralRésumé :
Extreme distribution is the distribution of a random variable that focuses on determining the probability of small values in the tail areaof the distribution. This distribution is widely used in various fields, one of which is reinsurance. An outbreak catastrophe is non-natural disaster that can pose an extreme risk of economic loss to a country that is exposed to it. To anticipate this risk, the government of a country can insure it to a reinsurance company which is then linkedto bonds in the capital market so that new securities are issued, namely outbreakcatastrophe bonds. In pricing, knowledge of the extreme distribution of economic losses due to outbreak catastrophe is indispensable. Therefore, this study aims to determine the extreme distribution model of economic losses due to outbreak catastrophe whose models will be determined by the approaches and methods of Extreme Value Theory and Peaks Over Threshold, respectively. The threshold value parameter of the model will be estimated by Kurtosis Method, while the other parameters will be estimated with Maximum Likelihood Estimation Method based on Newton-Raphson Iteration. The result of the research obtained is the resulting model of extreme value distribution of economic losses due to outbreak catastrophe that can be used by reinsurance companies as a tool in determining the value of risk in the outbreak catastrophe bonds.
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Marshall, Robert E., et Katherine L. Horgan. « Multi-wavelength radar target detection in an extreme advection duct event ». International Journal of Microwave and Wireless Technologies 3, no 3 (4 avril 2011) : 373–81. http://dx.doi.org/10.1017/s1759078711000225.
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Near sea surface radio frequency (RF) refraction is four dimensional (4D) and can significantly impact the performance of radar systems. The refractivity field is dictated by the vertical thermodynamic structure of the constantly evolving marine atmospheric boundary layer (MABL). Logistical and budgetary restraints on meteorological measurements over water to capture the spatio-temporal structure of refractivity fields influencing radar performance have limited the knowledge of how and why radar performance is azimuth, range, and time dependent. Rapidly increasing computer processing speeds and decreasing memory capacity costs have supported the horizontal and vertical resolution requirements for mesoscale numerical weather prediction (NWP) models to resolve the thermodynamic structure in the MABL. Once modeled, refractivity structure is easily calculated from the thermodynamic structure. Mesoscale NWP models coupled with modern parabolic equation radar performance models can support the prediction of 4D radar performance in challenging non-homogeneous, near surface refractivity fields at the time and location of the modeler's choice. The NWP modeling presented in this paper demonstrates how large-scale offshore flow of warm and dry air over colder seas produces strong near surface RF trapping. Large land-sea temperature differences can produce near shore sea breezes and surface-based ducts. This paper describes modeled radar performance in such a complex ducting structure over the Persian Gulf during large-scale northwest atmospheric flow. The refractivity field was resolved by the Coupled Ocean/ Atmosphere Mesoscale Prediction System (COAMPS® is a registered trademark of the Naval Research Laboratory) and the notional radar performance was modeled by the advanced refractive effects prediction system (AREPS). The results indicate strong spatial and wavelength-dependent enhancements and degradations in radar performance relative to a standard atmosphere.
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Wen, Yongfu, Peng Gao, Xingmin Mu, Mengzhen Li, Yongjun Su et Haixing Wang. « Experimental Study on Landslides in Terraced Fields in the Chinese Loessial Region under Extreme Rainfall ». Water 13, no 3 (22 janvier 2021) : 270. http://dx.doi.org/10.3390/w13030270.
Texte intégralRésumé :
Due to the development of the scale of tractor-ploughed terraces, terraces have been increasing in number, while global climate change is causing frequent extreme rainfall events in the Loess Plateau, resulting in many terrace landslides. To study the mechanism and process of shallow landslides and deep slip surface of terraces induced by extreme rainfall in loess hill and gully area, we conducted a laboratory model test of a terrace under artificial rainfall and used the Swedish arc strip method. The research results are as follows. The mechanism of shallow landslides in terraces is rill erosion accelerating rainfall infiltration, suspending the slope, and increasing its bulk density. The destruction process of shallow landslides can be roughly divided into six processes, and the earth volume of the landslide is 0.24 m3. The mechanism of the deep sliding surface in terraces occurs under the combined action of water erosion and gravity erosion. The soil moisture content increases, which decreases the anti-sliding moment and increases the sliding moment, and the safety factor becomes less than the allowable limit for terraces. The deep sliding deformation area of the terrace was 0~1.0 m below the slope surface, slip surface radius was 1.43 m, the slip surface angle was 92°, and the deep sliding surface began to form earlier than terraced shallow landslides. The displacement of the characteristic points increased from the slope top, to the slope center, and to the slope foot, with maximum displacements of 40.3, 15.5, and 6.0 mm, respectively.
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Wang, Bao-Lin, et Yiu-Wing Mai. « Closed-Form Solution for an Antiplane Interface Crack between Two Dissimilar Magnetoelectroelastic Layers ». Journal of Applied Mechanics 73, no 2 (17 juillet 2005) : 281–90. http://dx.doi.org/10.1115/1.2083827.
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In recent years, ferroelectromagnetic laminated composites have aroused worldwide research interest. In this paper, we developed a closed-form solution for antiplane mechanical and in-plane electric and magnetic fields for a crack between two dissimilar magnetoelectroelastic layers of finite thickness. Explicit expressions for stresses, electric and magnetic fields, together with their intensity factors are obtained for the two extreme cases of an impermeable and a permeable crack. Solutions for some special cases, such as a homogeneous magnetoelectroelastic layer, two magnetoelectroelastic layers with opposite poling directions, and a piezoelectric layer bonded to a piezomagnetic layer are also obtained. Explicit relations between the field intensity factors and the energy release rates for the interface crack are provided.
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He, Hongmei, Qiqi He, Hongchen Gao, Wei Hu et Song Xue. « Research on Postcuring Parameters Effect on the Properties of Fiberglass-Reinforced Silicone Resin Coil Bobbin ». Materials 16, no 7 (24 mars 2023) : 2588. http://dx.doi.org/10.3390/ma16072588.
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With the growing demand for insulation parts in extreme service environments, such as nuclear power, aviation, and other related fields, fiberglass-reinforced silicone resin (FRSR) has become a popular choice due to its exceptional physical and chemical properties in high-temperature and electromagnetic working environments. To enhance the performance of FRSR molded parts that can adapt to more demanding extreme environments, the oven postcuring process parameters on thermal stability and mechanical properties of the bobbin were investigated. The curing behavior of FRSR was analyzed by using thermogravimetric analysis (TGA) and the differential scanning calorimetry (DSC) method, and the bobbins were manufactured based on the testing results. Subsequently, the bobbins were oven postcured at different conditions, and the heat resistance and mechanical properties were analyzed by TGA and tensile tests. The results revealed that the tensile strength of the bobbin increased by 122%, and the weight loss decreased by 0.79% at 350 °C after baking at 175 °C for 24 h. The optimal process parameters for producing bobbins to meet the criteria of nuclear installations were determined to be a molding temperature of 120 °C, molding pressure of 50 MPa, pressure holding time of 3 min, oven postcuring temperature of 175 °C, and postcuring time of 24 h. The molded products have passed the thermal aging performance test of nuclear power units.
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W Callaghan, Chris. « Citizen Science and Biomedical Research : Implications for Bioethics Theory and Practice ». Informing Science : The International Journal of an Emerging Transdiscipline 19 (2016) : 325–43. http://dx.doi.org/10.28945/3579.
Texte intégralRésumé :
Certain trends in scientific research have important relevance to bioethics theory and practice. A growing stream of literature relates to increasing transparency and inclusivity of populations (stakeholders) in scientific research, from high volume data collection, synthesis, and analysis to verification and ethical scrutiny. The emergence of this stream of literature has implications for bioethics theory and practice. This paper seeks to make explicit these streams of literature and to relate these to bioethical issues, through consideration of certain extreme examples of scientific research where bioethical engagement is vital. Implications for theory and practice are derived, offering useful insights derived from multidisciplinary theory. Arguably, rapidly developing fields of citizen science such as informing science and others seeking to maximise stakeholder involvement in both research and bioethical engagement have emerged as a response to these types of issues; radically enhanced stakeholder engagement in science may herald a new maximally inclusive and transparent paradigm in bioethics based on lessons gained from exposure to increasingly uncertain ethical contexts of biomedical research.
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Mugume, Isaac, Charles Basalirwa, Daniel Waiswa, Joachim Reuder, Michel d. S. Mesquita, Sulin Tao et Triphonia J. Ngailo. « Comparison of Parametric and Nonparametric Methods for Analyzing the Bias of a Numerical Model ». Modelling and Simulation in Engineering 2016 (2016) : 1–7. http://dx.doi.org/10.1155/2016/7530759.
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Numerical models are presently applied in many fields for simulation and prediction, operation, or research. The output from these models normally has both systematic and random errors. The study compared January 2015 temperature data for Uganda as simulated using the Weather Research and Forecast model with actual observed station temperature data to analyze the bias using parametric (the root mean square error (RMSE), the mean absolute error (MAE), mean error (ME), skewness, and the bias easy estimate (BES)) and nonparametric (the sign test, STM) methods. The RMSE normally overestimates the error compared to MAE. The RMSE and MAE are not sensitive to direction of bias. The ME gives both direction and magnitude of bias but can be distorted by extreme values while the BES is insensitive to extreme values. The STM is robust for giving the direction of bias; it is not sensitive to extreme values but it does not give the magnitude of bias. The graphical tools (such as time series and cumulative curves) show the performance of the model with time. It is recommended to integrate parametric and nonparametric methods along with graphical methods for a comprehensive analysis of bias of a numerical model.
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Pohil, A. E. « Possible causes of extremely high waves in the Baltic Sea ». Hydrometeorological research and forecasting 3 (16 octobre 2020) : 58–70. http://dx.doi.org/10.37162/2618-9631-2020-3-58-70.
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Possible causes of extremely high waves in the Baltic Sea / Pohil A.E. // Hydrometeorological Research and Forecasting, 2020, no. 3 (377), pp. 58-70. The atmospheric conditions accompanying the occurrence of extremely high waves in the Baltic Sea (in particular, at the entrance to the Gulf of Bothnia) in 2004 and 2017 are analyzed. Changes in wave characteristics with a sharp decrease in the sea depth are considered. It is shown that the mechanisms like interference, when two wave systems overlap when rounding the island of Gotland, a superposition of a direct wave and a wave reflected from the steep slope at the entrance to the Gulf of Bothnia could contribute to the occurrence of extreme waves. Keywords: Baltic Sea, extreme waves, satellite data, water vapor fields Fig. 8. Ref. 19.
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Bochenek, Bogdan, et Zbigniew Ustrnul. « Machine Learning in Weather Prediction and Climate Analyses—Applications and Perspectives ». Atmosphere 13, no 2 (23 janvier 2022) : 180. http://dx.doi.org/10.3390/atmos13020180.
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In this paper, we performed an analysis of the 500 most relevant scientific articles published since 2018, concerning machine learning methods in the field of climate and numerical weather prediction using the Google Scholar search engine. The most common topics of interest in the abstracts were identified, and some of them examined in detail: in numerical weather prediction research—photovoltaic and wind energy, atmospheric physics and processes; in climate research—parametrizations, extreme events, and climate change. With the created database, it was also possible to extract the most commonly examined meteorological fields (wind, precipitation, temperature, pressure, and radiation), methods (Deep Learning, Random Forest, Artificial Neural Networks, Support Vector Machine, and XGBoost), and countries (China, USA, Australia, India, and Germany) in these topics. Performing critical reviews of the literature, authors are trying to predict the future research direction of these fields, with the main conclusion being that machine learning methods will be a key feature in future weather forecasting.
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Vasyechko, O. O., et O. F. Chetverikov. « Extremology : Behavioral and Quantitative Aspects ». Statistics of Ukraine 88, no 1 (1 mai 2020) : 24–34. http://dx.doi.org/10.31767/su.1(88)2020.01.03.
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The contemporary era features systematic correlations between creating wealth and the emergence of new and even more intensive risks. Globalization processes, volatile geopolitical conjunctures, global climate change, technological progress, which provoke constant and inevitable change in the environment of our existence, aggravate the condition of uncertainty at each level of the social life, thus increasing the social and psychological tensions. The latter constitute another source of risks manifesting in the emergence of extreme environments or extreme situations, apart from conventional risks of human existence. It raises the need for rethinking of established paradigms in psychology and related or other sciences in which the notion “extreme” is in a way explored, and their revision, in order to form a new scientific synergy for methodological support of preparing the population to behavioral adaptation and situational behavior in extreme environments and situations. This determines high importance of extremology as a new applied and interdisciplinary research filed. Considering the social demand, analysis of scientific sources and own experiences of the authors, extremology can be defined as the system for the protection of populations and active counteractions in the conditions of emerging extreme environments and extreme situations. It is argued that to be effective nowadays, such system should be built on methods developed as part of other fields of knowledge, i. e. risicology and statistics, especially the component of extreme risk control and quantitative assessment. But the latter cannot exclude studies of the possibilities for enhancing cross-disciplinary synergy of extremology through involving other methods and practices.
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Ferreira, Rosana Nieto. « Cut-Off Lows and Extreme Precipitation in Eastern Spain : Current and Future Climate ». Atmosphere 12, no 7 (28 juin 2021) : 835. http://dx.doi.org/10.3390/atmos12070835.
Texte intégralRésumé :
This study presents a seasonal synoptic climatology of cut-off lows (COLs) that produced extreme precipitation in the Valencia region of Spain during 1998–2018 and uses simulations with the Weather Research and Forecasting (WRF) model to study how extreme COL precipitation may change in a future warmer climate. COLs were shown to be the main producer of extreme precipitation in the Valencia region, especially during the transition seasons. The strongest raining COL events occurred during September–November. Six-day composites of thermodynamic and dynamic fields and precipitation show that COLs that produce extreme precipitation in this region remain stationary over Spain for 2–3 days and tend to produce precipitation over the Valencia region for at least two consecutive days. In the low levels these COLs are characterized by low pressure over the Mediterranean sea and winds with an easterly, onshore component thus fueling precipitation. Comparison of current and future climate ensembles of WRF simulations of 14 September–November extreme precipitation producing COL events suggest that in a warmer climate extreme COL precipitation may increase by as much as 88% in northeastern Spain and 61% in the adjoining Mediterranean Sea. These projected increases in extreme COL precipitation in the northeast of Spain present additional challenges to a region where COL flooding already has significant socio-economic impacts. Additionally, about half of the future climate COL event simulations showed increases in precipitation in the Valencian region of eastern Spain. These results provide important nuance to projections of a decreasing trend of total precipitation in the Iberian Peninsula as the climate warms.