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The divergence of nearby trajectories in soft-sphere DEM

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Particuology 2022年第4期20卷 1-8页

作者： William D.Fullmer Roberto Porcu Jordan Musser Ann S.Almgren Ishan Srivastava National Energy Technology Laboratory MorgantownWV 26507USA NETL Support contractor MorgantownWV 26507USA Center for Computational Sciences and Engineering.Lawrence Berkeley National Laboratory BerkeleyCA 94720USA

The n-body instability is investigated with the soft-sphere discrete element *** divergence of nearby trajectories is quantifed by the dynamical memory *** the inverse proportionality between the dynamical memory time and the largest Lyapunov exponent,the soft-sphere discrete ele-ment method results are compared to previous hard-sphere molecular dynamics data for the first *** agreement is observed at low concentrations and the degree of instability is shown to increase asymptotically with increasing spring *** particle concentrations above 30%,the soft-sphere Lya-punov exponents increase faster than the corresponding hard-sphere *** paper concludes with a demonstration of how this case study may be used in conjunction with regression testing and code verification activities.

关键词： Soft-sphere DEM Chaos Lyapunov exponent

Recent applications of isotope analysis to forensic anthropology

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Forensic Sciences research 2019年第1期4卷 29-44页

作者： Eric J.Bartelink Lesley A.Chesson Department of Anthropology California State UniversityChicoCAUSA contractor at Defense POW/MIA Accounting Agency(DPAA)Laboratory Pacific Architects and Engineers(PAE)HIUSA

Isotope analysis has become an increasingly valuable tool in forensic anthropology case-work over the past decade. Modern-day isotopic investigations on human remains have integrated the use of multi-isotope profiles (e.g. C, N, O, H, S, Sr, and Pb) as well as iso-topic landscapes ("isoscapes") from multiple body tissues (e.g. teeth, bone, hair, and nails) to predict possible region-of-origin of unidentified human remains. Together, data from various isotope analyses provide additional lines of evidence for human identification, including a decedent's possible region-of-birth, long-term adult residence, recent travel history, and dietary choices. Here, we present the basic principles of isotope analysis and provide a brief overview of instrumentation, analytical standards, sample selection, and sample quality measures. Finally, we present case studies that reflect the diverse applications of isotope analysis to the medicolegal system before describing some future research directions. As shown herein, isotope analysis is a flexible and powerful geolocation tool that can provide new investigative leads for unidentified human remains cases.

关键词： Forensic sciences forensic anthropology stable isotope analysis isoscapes provenancing

Deepwater oil and gas field development in South China Sea

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Engineering Sciences 2013年第4期11卷 2-9页

作者： Zhang Dagang Wybro Pieter Kang Yongtian DMAR Engineering Inc. Independent contractor Former President of Sea Engineering Inc.

This paper focuses on potential development models of future oil and gas exploration in South China Sea. A detailed study of current development models worldwide is performed through some examples of industry installed/ongoing projects and major technical issues encountered during these practice. Key technologies are discussed for the success of field development. Some of the technologies and field development experience can be used for South China Sea project. Several models are studied in field development for different scenarios,including marginal field,large oil field and gas field. With the massive investment activities,continued improved technologies,and rapidly growing pool of professionals,the offshore industry in China will soon encounter a golden period.

关键词： field development deepwater exploration development model deepwater technology combinedsystem

Modelling Regional Land Change Scenarios to Assess Land Abandonment and Reforestation Dynamics in the Pyrenees(France)

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Journal of Mountain Science 2015年第4期12卷 905-920页

作者： Laure A.VACQUIE Thomas HOUET Terry L.SOHL Ryan REKER Kristi L.SAYLER GEODE Laboratory Toulouse Jean Jaurès University U.S.Geological Survey Earth Resources Observation and Science (EROS) Center ASRC Federal – Inu Teq Contractor to U.S.Geological Survey Earth Resources Observation and Science (EROS) Center

Over the last decades and centuries,European mountain landscapes have experienced substantial *** and anthropogenic LULC changes(land use and land cover changes), especially agro-pastoral activities,have directly influenced the spatial organization and composition of European mountain *** the past sixty years, natural reforestation has been occurring due to a decline in both agricultural production activities and rural ***, to better anticipate future changes,need spatially and temporally explicit models to identify areas at risk of land change and possible *** paper presents an integrated approach combining forecasting scenarios and a LULC changes simulation model to assess where LULC changes may occur in the Pyrenees Mountains,based on historical LULC trends and a range of future socio-economic *** proposed methodologyconsiders local specificities of the Pyrenean valleys,sub-regional climate and topographical properties,and regional economic *** indicate that some regions are projected to face strong abandonment, regardless of the scenario ***, high rates of change are associated with administrative regions where land productivity is highly dependent on socio-economic drivers and climatic and environmental conditions limit intensive(agricultural and/or pastoral) production and *** combination of the results for the four scenarios allows assessments of where encroachment(*** by shrublands) and reforestation are the most *** assessment intends to provide insight into the potential future development of the Pyrenees to help identify areas that are the most sensitive to change and to guide decision makers to help their management decisions.

关键词： Pyrenees Land use change Land cover change Land abandonment Mountain landscapeReforestation LULC Model

Directional Overcurrent Relays Coordination Restoration by Reducing Minimum Fault Current Limiter Impedance

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Journal of Energy and Power Engineering 2014年第6期8卷 1132-1141页

作者： Saadoun Abdel Aziz Mostafa DoaaKhalil Ibrahim Essam El-Din Abo El-Zahab Arab contractor Company Nasr City 11852 Egypt Faculty of Engineering Cairo University Giza 12613 Egypt

FCL （fault current limiter） is used to solve relays miscoordination problem arises from DG （distributed generation） installation. In most published researches, different optimization methods are developed to obtain optimal relay settings to achieve coordination in case of not installing DG, then depending on the achieved optimal obtained relay settings, FCL impedance is deduced to ensure relays coordination restoration in case of installing DG. Based on original optimal relay settings, obtained FCL impedance is not the minimum one required to achieve relay coordination. The contribution of this paper is the generation of multi sets of original relay settings that increase the possibility of finding FCL impedance of minimum value which is lower than the calculated value based on original optimal relay settings. The proposed method achieves better economic target by reducing FCL impedance. The proposed approach is implemented and tested on IEEE-39 bus test system.

关键词： FCL (fault current limiter) IP (pickup current setting) relays coordination TDS (time-dial setting).

The integration of geophysical and enhanced Moderate Resolution Imaging Spectroradiometer Normalized Difference Vegetation Index data into a rule-based, piecewise regression-tree model to estimate cheatgrass beginning of spring growth

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International Journal of Digital Earth 2015年第2期8卷 118-132页

作者： Stephen P.Boyte Bruce K.Wylie Donald J.Major Jesslyn F.Brown Stinger Ghaffarian Technologies Inc.Contractor to the USGS Earth Resources Observation and Science(EROS)CenterSioux FallsSDUSA USGS Earth Resources Observation and Science(EROS)Center Sioux FallsSDUSA U.S.Bureau of Land Management-Great Basin Restoration Initiative BoiseIDUSA

Cheatgrass exhibits spatial and temporal phenological variability across the Great Basin as described by ecological models formed using remote sensing and other spatial *** developed a rule-based,piecewise regression-tree model trained on 99 points that used three data-setslatitude,elevation,and start of season time based on remote sensing input datato estimate cheatgrass beginning of spring growth(BOSG)in the northern Great *** model was then applied to map the location and timing of cheatgrass spring growth for the entire *** model was strong(R^(2)=0.85)and predicted an average cheatgrass BOSG across the study area of 29 March–4 *** early cheatgrass BOSG areas,65% occurred at elevations below 1452 *** highest proportion of cheatgrass BOSG occurred between mid-April and late *** cheatgrass BOSG in this study matched well with previous Great Basin cheatgrass green-up studies.

关键词： remote sensing invasive species ecological model Great Basin phenology

The Standard Model Theory [May Be] a Wrong Theory

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Journal of High Energy Physics, Gravitation and Cosmology 2023年第3期9卷 602-610页

作者： Vaggelis Talios National Technical University of Athens (NTUA) Athens Greece Independent researcher E/M Projects Designer and Contractor Engineer Athens Greece

The Standard Model is the theory of Physics that describes the elementary particles of matter and the strong, weak and electromagnetic interactions, between them. The theory of the Standard Model does not include the description of the gravitational interactions. It is a very well founded theory that has predicted many experimental results, such as the existence of many particles and has withstood many experimental tests. The key missing piece of the theory to fill in was the Higgs boson, whose existence was reasonably suspected and confirmed by CERN’s ATLAS and CMS experiments in 2012. The current synthesis of the theory was completed in the mid-1970s, after the experimental confirmation of the existence of the quarks, and then confirmed, with the discovery of the Higgs boson, in 2012. All these, are according to the established views of science. But according to the opinions of many scientists, opinions with which I as the author of this paper agree, the theory of the Standard Model is a wrong theory because, while it makes some successful predictions, it does not answer to a number of many other questions that it should answer for its final establishment. Specifically and according to established views, the theory cannot explain the existence of dark matter and dark energy, the behavior of neutrinos and the existence of particles with very different masses. It is also questionable whether the Higgs boson, discovered in the ATLAS experiment is actually the particle that contributes to the creation of the mass of the elementary particles of matter, and whether the Higgs mechanism is theoretically a correct mechanism. There is doubt if the interactions, actually be created by the exchange of bosons? If bosons are really exist? And not any convincing explanation is given by the theory, for the case that, the bosons exist as particles, where were they found? And how do they work? For replace, or fill the void will be left by the theory of the Standard Model, which I b

关键词： Standard Model Elementary Particles Higgs Boson New Model Interactions

A Web-Based Application for Exploring Potential Changes in Design Peak Flow of US Urban Areas Driven by Land Cover Change

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Journal of Remote Sensing

Journal of Remote Sensing 2023年第1期3卷 125-137页

作者： Kul Khand Gabriel B.Senay ASRC Federal Data Solutions Contractor to U.S.Geological Survey(USGS)Earth Resources Observation and Science(EROS)CenterSioux FallsSD 57198USA U.S.Geological Survey(USGS)Earth Resources Observation and Science(EROS)Center North Central Climate Adaptation Science CenterFort CollinsCO 80523USA

Floods have become increasingly prominent in recent decades causing devastating effects on lives and livelihoods *** tools to assess the drivers of floods,such as increasing urbanization,could help to minimize flood *** increases the design peak flow(maximum potential surface water flow from a precipitation event with an average probability of occurring once in a specific recurrence interval),which is a key information needed for designing stormwater management infrastructures such as culverts and storm sewers.A web-based application was developed to explore the potential changes(1985 to 2020)in design peak flow of urban areas across the conterminous United States driven by land cover *** results indicate a potential increase in design peak flow in urban areas up to 126.6% in 2020 compared to *** the total 3,535 study urban areas,about 80%(2,840)urban areas increased design peak flow,and about 19%(654)decreased design peak flow.A general pattern of increasing design peak flow was observed during 1985 to 2010,and decreasing pattern was observed during 2010 to 2020,primarily driven by respective increasing(decreasing)and decreasing(increasing)developed areas(croplands).The application provides crucial information by visualizing both spatial and temporal data that could be useful for decision-makers in developing and improving urban stormwater management plans and policies for efficient resource allocations and reducing flood risks.

关键词： storm flood floods

Clinical Management and Evaluation of White Spot Lesions: A Report of 11 Cases

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Open Journal of Stomatology 2020年第7期10卷 156-173页

作者： Domenico Aiello Riccardo Pulcini Sandro Sestito Michele Mario Figliuzzi Sergio Paduano Department of Health Sciences “Magna Graecia” University of Catanzaro Catanzaro Italy Department of Medical Oral and Biotechnological Sciences University of Chieti Chieti Italy Privat contractor Italy

Introduction: Today’s society is always more interested to the concept of aesthetics. The patients frequently ask to dentist to resolve unaesthetic problems of teeth, in particular that of the upper frontal group. The WSLs are enamel white alterations due to alteration during the demineralization and remineralization of enamel. This effect is caused by alteration of the pH in the oral cavity and buffer action of saliva. An alteration of this relationship leads to a progressive demineralization of enamel until the formation of a dental cavitation. Materials and Methods: For this study are selected 11 patients, of which 3 men and 8 women, with total of 17 WSLs. The inclusion criteria included WLSs with ICDAS = 2 and WLSs caused by hypomineralization of traumatic origin. These patients were subjected to treatment with infiltrating resin according to operative procedure. Discussion: The therapy with infiltrating resin gave great results in 12 lesions out of 17. In the lesions where there weren’t a complete remission we obtained a great aesthetic improvement and a good reduction of lesions. The follow up could improve the result after a better rehydration of hard tissue. Conclusions: With a correct selection of cases and good operative procedure, the use of the micro-infiltrative technique by low viscosity resin is a good procedure to resolve WSLs problems of non-orthodontic origins. Other studies with a larger sample are required to validate this clinical approach.

关键词： WSL Microinfiltration Demineralization Icon Enamel