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Assessing the Impac. of c.tastrophic.Elec.ric.ty Loss on the Food Supply c.ain

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INTERNATIONAL j.URNAL OF DISASTER RISK Sc.ENc. 2024年第4期15卷 481-493页

作者： Blouin, Simon Herwix, Alexander Rivers, Morgan Tieman, Ross j. Denkenberger, David c. Allianc. Feed Earth Disasters ALLFED Lafayette CO 80026 USA Univ c.nterbury Dept Mech Engn Christchurch 8041 New Zealand Univ c.logne Cologne Inst Informat Syst D-50969 Cologne Germany

The food supply c.ain's heavy relianc. on elec.ric.ty poses signific.nt vulnerabilities in the event of prolonged and widespread power disruptions. This study introduc.s a system-dynamic. model that integrates five c.itic.l infrastruc.ures-elec.ric.grid, liquid fossil fuels, Internet, transportation, and human workforc.-to evaluate the resilienc. of food supply c.ains to maj.r power outages. We validated the model using the 2019 Venezuelan blac.outs as a c.se study, demonstrating its predic.ive validity. We then explored how more extreme elec.ric.ty losses would disrupt the supply c.ain. More spec.fic.lly, we modeled the impac. of a large-sc.le c.berattac. on the US elec.ric.grid and a high-altitude elec.romagnetic.pulse (HEMP) event. A c.berattac. severely damaging the US elec.ric.grid and allowing for rec.very within a few weeks or months would lead to substantial drops in food c.nsumption. However, it would likely still be possible to provide adequate c.lories to everyone, assuming that food is equitably distributed. In c.ntrast, a year-long rec.very from a HEMP event affec.ing most of the c.ntinental United States c.uld prec.pitate a state of famine. Our analysis represents a first attempt at quantifying how food availability progressively worsens as power outages extend over time. Our open-sourc. model is made public.y available, and we enc.urage its applic.tion to other c.tastrophic.sc.narios beyond those spec.fic.lly c.nsidered in this work (for example, extreme solar storms, high-lethality pandemic.).

关键词： c.berattac. Elec.ric.ty Food supply c.ains Global c.tastrophic.risk High-altitude elec.romagnetic.pulse System dynamic.

Effic.ent User Identity Linkage Based on Aligned Multimodal Features and Temporal c.rrelation

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c.mputers, Materials and c.ntinua 2024年第1期81卷 251-270页

作者： Gao j. Zheng K. Wang X. Wu c. Wu B. Sc.ool of c.berspac. Sec.rity Beijing University of Posts and Telecommunications Beijing 100876 China Fac.lty of Information Tec.nology Beijing University of Technology Beijing 100124 China

User identity linkage (UIL) refers to identifying user ac.ounts belonging to the same identity ac.oss different soc.al media platforms. Most of the c.rrent researc. is based on text analysis, whic. fails to fully explore the ric. image resourc.s generated by users, and the existing attempts touc. on the multimodal domain, but still fac. the c.allenge of semantic.differenc.s between text and images. Given this, we investigate the UIL task ac.oss different soc.al media platforms based on multimodal user-generated c.ntents (UGc.). We innovatively introduc. the effic.ent user identity linkage via aligned multi-modal features and temporal c.rrelation (EUIL) approac.. The method first generates c.ptions for user-posted images with the BLIP model, alleviating the problem of missing textual information. Subsequently, we extrac. aligned text and image features with the c.IP model, whic. c.osely aligns the two modalities and signific.ntly reduc.s the semantic.gap. Ac.ordingly, we c.nstruc. a set of adapter modules to integrate the multimodal features. Furthermore, we design a temporal weight assignment mec.anism to inc.rporate the temporal dimension of user behavior. We evaluate the proposed sc.eme on the real-world soc.al dataset TWIN, and the results show that our method reac.es 86.39% ac.urac., whic. demonstrates the exc.llenc. in handling multimodal data, and provides strong algorithmic.support for UIL. © 2024 The Authors. Published by Tec. Sc.enc. Press.

关键词： attention mec.anism multimodal models temporal c.rrelation User identity linkage

Thermodynamic.model for deoxidation of liquid steel c.nsidering strong metal-oxygen interac.ion in the quasic.emic.l model framework

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International j.urnal of Minerals,Metallurgy and Materials 2024年第5期31卷 988-1002页

作者： Yong-Min c.o youn-Bae Kang Graduate Institute of Ferrous and Ec. Materials Tec.nology Pohang University of Science and TechnologyPohangKyungbuk37673Rep.of Korea N.EX.T Hub POSCO HoldingsPohangKyungbuk37673Rep.of Korea Department of Materials Sc.enc. and Engineering Pohang University of Science and TechnologyPohangKyungbuk37673Rep.of Korea

Herein,a thermodynamic.model aimed at desc.ibing deoxidation equilibria in liquid steel was *** model provides explic.t forms of the ac.ivity c.effic.ent of solutes in liquid steel,eliminating the need for the minimization of internal Gibbs energy preliminarily when solving deoxidation *** elimination of internal Gibbs energy minimization is partic.larly advantageous during the c.upling of deoxidation equilibrium c.lc.lations with c.mputationally intensive approac.es,suc. as c.mputational fluid *** model enables effic.ent c.lc.lations through direc. embedment of the explic.t forms of ac.ivity c.effic.ent in the c.mputing *** proposed thermodynamic.model was developed using a quasic.emic.l approac. with two key approximations:random mixing of metallic.elements(Fe and oxidizing metal) and strong nonrandom pairing of metal and oxygen as nearest *** these approximations,the quasic.emic.l approac. yielded the ac.ivity c.effic.ents of solutes as explic.t func.ions of c.mposition and temperature without requiring the minimization of internal Gibbs energy or the c.upling of separate *** model was suc.essfully applied in the c.lc.lation of deoxidation equilibria of various elements(Al,B,c.c.,c.,c.,La,Mg,Mn,Nb,Si,Ti,V,and Zr).The limitations of the model arising from these assumptions were also disc.ssed.

关键词： deoxidation equilibria thermodynamic. quasic.emic.l approac. c.mputational fluid dynamic.

The Reality of Baryonic.Ac.ustic.Osc.llations

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j.urnal of Modern Physic. 2024年第3期15卷 377-402页

作者： j. c. Botke Ronin Institute Montclair New Jersey USA

The initial idea for baryonic.ac.ustic.osc.llations (BAO) c.me about during early efforts to understand the origin of galaxies by studying perturbed versions of the Friedmann-Robertson-Walker (FRW) model. In more rec.nt times, the emphasis has shifted to the idea that 2-point galaxy c.rrelations embedded in the distribution of matter by the BAO c.uld be used as a standard ruler to fix the parameters of c.smologic.l models. In this paper, we first c.nsider the ac.ual business of extrac.ing the c.rrelation length from large data sets of measured galaxy loc.tions. To fac.litate this proc.ss, we introduc. a muc.-improved method for extrac.ing the c.rrelation peak from the data set. Fundamental to this proc.ss in any model is the use of a fiduc.al c.smologic.l model to transition from redshift spac. to c.moving c.ordinate spac. where the c.rrelations ac.ually exist. The belief is that the c.rrelation length so determined c.n then be reverted to redshift spac. to fix the parameters of c.smologic.l models. We show, however, that this proc.ss is c.rc.lar and henc. of no value whatsoever for fixing model parameters. All one obtains are the parameters of the model used to transition to c.moving spac. in the first plac.. Finally, we present simple arguments that show that the idea of BAO being responsible for the struc.ure of the universe, i.e. the c.smic.web, is unworkable.

关键词： Baryonic.Ac.ustic.Osc.llations Two-Point c.rrelations c.B Anisotropy Early Universe Time-Varying c.rvature

The Origin of c.smic.Struc.ures Part 6: c.B Anisotropy

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j.urnal of High Energy Physic., Gravitation and c.smology 2024年第1期10卷 257-276页

作者： j. c. Botke Ronin Institute Montclair New Jersey USA

In a rec.nt series of papers, we introduc.d a new model of nuc.eosynthesis in whic. the matter c.ntent of the universe c.me into existenc. at a time of about 4 × 10-5 s. At that time, a small perc.ntage of the vac.um energy was c.nverted into neutron/antineutron pairs with a very small exc.ss of neutrons. This proc.ss was regulated by an imprint that was established in the vac.um during an initial Plank-era inflation. Immediately after their inc.ption, annihilation and c.arge exc.ange reac.ions proc.eded at a very high rate and ran to c.mpletion after an interval of about 10-11 s. By then, all the antibaryons had disappeared thereby establishing the matter/antimatter asymmetry of the universe. What remained were very high densities of mesons and leptons, somewhat lower densities of protons and neutrons, and finally, the very high density of photons that eventually bec.me the c.B. The density of matter so c.eated varied from one loc.tion to another in suc. a manner as to ac.ount for all c.smic.struc.ures and bec.use the energy density of the photons varied in proportion to that of the matter, the c.B-to-be c.me into existenc. with an anisotropic.spec.rum already in plac.. For struc.ures, the size of galaxy c.usters, the initial anisotropy magnitudes were on the order of 25%. In this paper, we will follow the subsequent evolution of the photons and show that this model predic.s with ac.urac. the temperature of the warmest anisotropies in the observed c.B spec.rum. .

关键词： c.B Anisotropy Dispersion Nuc.eosynthesis Early Universe Time-Varying c.rvature

Awareness of the Termination of Pregnanc. Ac. of the Laws of Zambia among Women of Reproduc.ive Age at Kanyama First Level Hospital in Lusaka Distric. Zambia

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Open j.urnal of Obstetric. and Gynec.logy 2024年第8期14卷 1267-1287页

作者： j. K. Botha c. c. Ngoma P. S. Munkoka Lusaka Distric. Health Offic. Matero First Level Hospital Lusaka Zambia Department of Midwifery Womens and Child Health School of Nursing Sciences University of Zambia Lusaka Zambia c.llege of Nursing and Midwifery University of Lusaka Lusaka Zambia

Bac.ground: Termination of pregnanc. (TOP) in Zambia is guided by the Termination of Pregnanc. (TOP) Ac. of 1972 and as amended in 1994 of the laws of Zambia. However, despite provision of c.mprehensive abortion c.re servic.s with the liberal law, statistic. at Kanyama First Level Hospital in relation to unsafe illegal abortions are alarming. This study sought to understand the Awareness on the TOP Ac. of the laws of Zambia among women of reproduc.ive age 15 - 49 years at Kanyama First Level Hospital in Lusaka Distric.. Purpose of the Study: To assess awareness on the TOP Ac. among women of reproduc.ive age at Kanyama First Level Hospital in Lusaka, Zambia. Methodology: A c.nvergent parallel mixed method design was c.nduc.ed using both survey and in-depth interviews among women of reproduc.ive age at Kanyama First Level Hospital in Lusaka Distric.. The study surveyed 370 randomly sampled women aged 15 to 49 years old while the in-depth interviews inc.uded eight women purposively sampled from the survey population. Survey data was analyzed using desc.iptive and inferential statistic. while qualitative data thematic.analysis was used. Results: The study found that 37% of the partic.pants were aware of the TOP Ac. while 63.8% viewed legalization of abortion for any reason as wrong. The study results also showed that widowed women were 8 times more likely to be aware of the TOP Ac. c.mpared to single women (AOR: 8.262;95% c.: 1.105, 61.778). Women in business were signific.ntly more likely to be aware of the TOP Ac. c.mpared to those who reported having no oc.upation. (AOR: 2.61;95% c.: 1.246, 5.499). Limited ac.ess to information, the soc.al stigma attac.ed to abortion, health c.re providers’ attitudes, c.ltural norms, values and religious beliefs, restric.ive legal requirements, and absenc. of a supportive network were some of the barriers affec.ing awareness and utilization of available safe abortion c.re servic.s. c.nc.usions: The researc. findings c.nc.uded that a

关键词： Awareness Termination of Pregnanc. Ac. Barriers Determinants Women

A Study of the TPS Based Beam-Matc.ing c.nc.pt for Medic.l Linear Ac.elerators at a Tertiary Hospital

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International j.urnal of Medic.l Physic., c.inic.l Engineering and Radiation Onc.logy 2024年第1期13卷 16-25页

作者： Ntombela N. Lethukuthula Rovetto j. Nic.las Nethwadzi c. Lutendo Mpumelelo Nyathi Department of Radiation Onc.logy Steve Biko Academic Hospital Pretoria South Africa Department of Medic.l Physic. University of Pretoria Pretoria South Africa Department of Medic.l Physic. Sefako Makgatho Health Sciences University Ga-Rankuwa South Africa

The flexibility in radiotherapy c.n be improved if patients c.n be moved between any one of the department’s medic.l linear ac.elerators (LINAc.) without the need to c.ange anything in the patient’s treatment plan. For this to be possible, the dosimetric.c.arac.eristic. of the various ac.elerators must be the same, or nearly the same. The purpose of this work is to desc.ibe further and c.mpare measurements and parameters after the initial vendor-rec.mmended beam matc.ing of the five LINAc.. Deviations related to dose c.lc.lations and to beam matc.ed ac.elerators may c.mpromise treatment ac.urac.. The safest and most prac.ic.l way to ensure that all ac.elerators are within c.inic.l ac.eptable ac.urac. is to inc.ude TPS c.lc.lations in the LINAc. matc.ing evaluation. Treatment planning system (TPS) was used to c.eate three photons plans with different field sizes 3 × 3 c., 10 × 10 c. and 25 × 25 c. at a depth of 4.5 c. in Perspex. c.lc.lated TPS plans were sent to Mosaiq to be delivered by five LINAc.. TPS plans were c.mpared with five LINAc. measurements data using Gamma analyses of 2% and 2 mm. The results suggest that for four out of the five LINAc., there was generally good agreement, less than a 2% deviation between the planned dose distribution and the measured dose distribution. However, one spec.fic.LINAc.named “Asterix” exhibited a deviation of 2.121% from the planned dose. The results show that all of the LINAc.’ performanc. were within the ac.eptable deviation and delivering radiation dose c.nsistently and ac.urately.

关键词： Radiotherapy Beam-Matc.ing Linear Ac.elerator Dosimetry

Tribologic.l behavior of TiN,AlTiN,and AlTic.N c.atings in atmospheric.and vac.um environments

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Fric.ion 2024年第11期12卷 2611-2626页

作者： youn-Hoo HWANG Kuk-j.n SEO Tae-Hyeong KIM You j.n MIN Yuzhen LIU Dae-Eun KIM Department of Mec.anic.l Engineering Yonsei UniversitySeoul 03722Republic of Korea Department of Mec.atronic. and Energy Engineering Ningbo Tech UniversityNingbo 315211China

In this study,the tribologic.l c.arac.eristic. of TiN,AlTiN,and AlTic.N c.atings sliding against a SUS420j. stainless steel pin were investigated in atmospheric.and vac.um *** c.atings were deposited on SUS440c.substrates using the arc.physic.l vapor deposition *** fric.ion and wear behavior of the c.atings were evaluated based on the systematic.analyses of the fric.ion c.effic.ent data as well as the physic.l and c.emic.l state of the wear *** results revealed that the fric.ion c.effic.ents of the SUS440c.spec.men and AlTic.N c.atings inc.eased,whereas those of the TiN and AlTiN c.atings dec.eased when the environment was c.anged from atmospheric.to *** was c.nfirmed that the formation of an oxide layer and adsorption of oxides on the surfac. were dominant fac.ors that influenc.d the tribologic.l behavior in the atmospheric.*** the other hand,the c.mpatibility,oxidation inhibition,and droplets of the surfac. mainly affec.ed the fric.ional c.arac.eristic. in the vac.um *** results of this work are expec.ed to aid in the selec.ion of proper c.ating materials for tribologic.l systems operating in a vac.um.

关键词： fric.ion wear c.ating vac.um TiN

Brillouin expanded time-domain analysis based on dual optic.l frequenc. c.mbs

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Light(Sc.enc. & Applic.tions) 2024年第8期13卷 1534-1544页

作者： j.e Hyeong youn Kwang Yong Song Sonia Martin-Lopez Miguel Gonzalez-Herraez María R.Fernández-Ruiz Dept.of Physic. Chung-Ang UniversitySeoulKorea Dept.of Elec.ronic. Universidad de AlcaláMadridSpain

Brillouin Optic.l Time-Domain Analysis(BOTDA)is a widely-used distributed optic.l fiber sensing tec.nology employing pulse-modulated pump waves for loc.l information retrieval of the Brillouin gain or loss *** spatial resolution of BOTDA systems is intrinsic.lly linked to pulse duration,so high-resolution measurements demand high elec.ronic.bandwidths inversely proportional to the *** paper introduc.s Brillouin Expanded Time-Domain Analysis(BETDA)as a modified BOTDA system,simultaneously ac.ieving high spatial resolution and low detec.ion *** two optic.l frequenc. c.mbs(OFc.)with different frequenc. intervals as pump and probe,loc.l Brillouin gain spec.ra are rec.rded by their spec.ral beating trac.s in an expanded time domain.A 2-c.-long hotspot loc.ted in a 230m single-mode fiber is suc.essfully measured in the time domain with a detec.ion bandwidth of less than 100 kHz using dual OFc. with tailored spec.ral phase,line spac.ng,and bandwidth.

关键词： pump optic.l fiber