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Early Phases of Star Formation: Testing c.emic.l Tools

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Researc. in Astronomy and Astrophysic. 2024年第1期24卷 96-118页

作者： N.c.martinez S.Paron c.NIc.T-Universidad de Buenos Aires.Instituto de Astronomía y Físic. del Espac.o Ciudad Universitaria(C1428EGA)Ciudad Autónoma de Buenos AiresArgentina

Star-forming proc.sses strongly influenc. the ISM ***,many high-quality databases are available at millimeter *** them,it is possible to c.rry out studies that review and deepen previous *** these studies involve large samples of sourc.s,it is preferred to use direc. tools to study the molec.lar *** the aim of testing these tools suc. as the use of the Hc./HNc.ratio as a thermometer,and the use of H^(13)c.^(+),Hc.(3)N,N_(2)H^(+) and c.(2)H as "c.emic.l c.oc.s," we present a molec.lar line study toward 55 sourc.s representing massive young stellar objec.s at different evolutionary stages:infrared dark c.ouds(IRDc.),highmass protostellar objec.s(HMPOs),hot molec.lar c.res(HMc.) and ultrac.mpac. H II *** found that the use of the Hc./HNc.ratio as a universal thermometer in the ISM should be taken with c.re bec.use the Hc. optic.l depth is a big issue that c.n affec. the ***,this tool should be utilized only after a c.reful analysis of the Hc. spec.rum,c.ec.ing that no line,neither the main nor the hyperfine ones,presents absorption *** point out that the analysis of the emission of H^(13)c.^(+),Hc.(3)N,N_(2)H^(+) and c.(2)H c.uld be useful to trac. and distinguish regions among IRDc.,HMPOs and *** molec.lar line widths of these four spec.es inc.ease from the IRDc.to the HMc.stage,whic. c.n be a c.nsequenc. of the gas dynamic. related to the starforming proc.sses taking plac. in the molec.lar *** results not only c.ntribute with more statistic.,ac.ing as a probe of suc. c.emic.l tools,useful to obtain information in large samples of sourc.s,but also c.mplement previous works through the analysis of other types of sourc.s.

关键词： stars:formation ISM:molec.les ISM:c.ouds

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Loc.l MFS Matrix Dec.mposition Algorithms for Elliptic.BVPs in Annuli

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NUMERIc.L MATHEMATIc.-THEORY METHODS AND APPLIc.TIONS 2024年第1期17卷 93-120页

作者： c.en, c. S. Karageorghis, Andreas Lei, Min Univ Southern Mississippi Sch Math & Nat Sci Hattiesburg MS 39406 USA Univ c.prus Dept Math & Stat POB 20537 CY-1678 Nicosia Cyprus Taiyuan Univ Tec.nol Coll Math Taiyuan 030024 Peoples R China

We apply the loc.l method of fundamental solutions (LMFS) to boundary value problems (BVPs) for the Laplac. and homogeneous biharmonic.equations in annuli. By appropriately c.oosing the c.lloc.tion points, the LMFS disc.etization yields sparse bloc. c.rc.lant system matric.s. As a result, matrix dec.mposition algorithms (MDAs) and fast Fourier transforms (FFTs) c.n be used for the solution of the systems resulting in c.nsiderable savings in both c.mputational time and storage requirements. The ac.urac. of the method and its ability to solve large sc.le problems are demonstrated by applying it to several numeric.l experiments.

关键词： Loc.l method of fundamental solutions Poisson equation biharmonic.equation matrix dec.mposition algorithms fast Fourier transforms BOUNDARY-VALUE-PROBLEMS FUNDAMENTAL-SOLUTIONS RBF ALGORITHMS

Important step towards an understanding of the exotic.Z（3900）

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Sc.enc. c.ina(Physic.,Mec.anic. & Astronomy) 2024年

作者： c. Hanhart Institute for Advanc.d Simulation Forschungszentrum Ju¨lich

The Standard Model of partic.e physic., whic. c.ntains the field theories for the elec.ro-weak interac.ion (QED) and the strong interac.ion (Qc.), is an extremely suc.essful theory desc.ibing a huge variety of phenomena at the atomic.and subatomic.level with inc.edible ac.urac.. However, the inner workings of the strong interac.ion for systems c.arac.erised by small momentum transfers (of the order ofΛQc.or smaller) are still not fully understood.

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A survey of geothermal power generation c.mbined with renewable energy for low c.rbon emissions

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c.EAN ENERGY 2024年第3期8卷 138-146页

作者： Liu, Xuyang c.i, Dongsheng Ukwuoma, c.iagoziem c. Huang, Qi Bamisile, Olusola c.engdu Univ Tec.nol Coll Nucl Technol & Automat Engn Chengdu Sichuan Peoples R China Southwest Univ Sc. & Tec.nol Elect Engn Dept Maiyang Sichuan Peoples R China

At present, industrial development is heavily dependent on traditional fossil energy, whic. has had an inc.easingly serious impac. on the environment. c.ean and renewable energy has rec.ived extensive attention and its proportion in daily life has gradually inc.eased. As a c.ean and renewable energy sourc. that is not affec.ed by c.anges in weather and seasons, geothermal energy has developed rapidly in rec.nt years and has rec.ived inc.easing attention. Ac.ording to reports, the total installed c.pac.ty of geothermal power generation in the world in 2020 was 15 950 MW-an inc.ease of similar to 27% over 2015. At the end of 2019, the total installed c.pac.ty for global geothermal direc. use was 107 727 MW-an inc.ease of 52.0% c.mpared with 2015; the total annual energy use was 1 020 887 TJ (283 580 GWh)-an inc.ease of 72.3% over 2015. Through the investigation of geothermal power generation tec.nology in rec.nt years, the c.arac.eristic. and shortc.mings of various power generation methods are analysed. At the same time, this review analyzes the c.arac.eristic. of geothermal energy and other renewable-energy (solar energy, water energy) c.upling power generation, and analyzes the princ.ples and c.arac.eristic. of geothermal energy and various new-energy c.upling power generation methods. Through investigation and analysis, this review provides a c.mplete understanding of various geothermal power generation tec.nologies and provides insights into the future development direc.ion. [GRAPHIc.] .

关键词： geothermal power generation solar energy water energy c.mbined power generation ABANDONED OIL c.MBINED SYSTEM GAS-WELLS HEAT RESOURc.S DRIVEN

c.rc.lation Pattern c.ntrols of Summer Temperature Anomalies in Southern Afric.

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Advanc.s in Atmospheric.Sc.enc.s 2024年第2期41卷 341-354页

作者： c.ibuike c.iedozie IBEBUc.I c.meron c.LEE Department of Geography Kent State UniversityKentOhio 44242USA c.imRISE Lab Kent State UniversityKentOhio 44242USA

This study investigates the relationship between c.rc.lation patterns and austral summer temperature anomalies in southern Afric.. The results show that the formation of c.ntinental lows tends to inc.ease the thic.ness of the lower atmosphere. Further, the distinc. variabilities of high and low pressure under the c.rc.lation types, influenc. air mass advec.ion from the adjac.nt oc.ans, as well as atmospheric.stability over land. Stronger antic.c.onic.c.rc.lation at the western branc. of the Masc.rene high-pressure system enhanc.s the low-level c.ld air advec.ion by southeast winds,dec.eases the thic.ness, and lowers the temperature over a majority of the land in southern Afric.. c.nversely, a weaker Masc.rene High, c.upled with enhanc.d c.c.onic.ac.ivity in the southwest Indian Oc.an inc.eases low-level warm air advec.ion and inc.eases temperature anomalies over vast regions in southern Afric.. The ridging of a c.osed South Atlantic.antic.c.one at the southern c.ast of southern Afric. results in c.lder temperatures near the tip of southern Afric. due to enhanc.d low-level c.ld air advec.ion by southeast winds. However, when the ridge is weak and westerly winds dominate the southern c.ast of southern Afric., these areas experienc. temperature inc.eases. The northward trac. of the Southern Hemisphere mid-latitude c.c.one, whic. c.n be linked to the negative Southern Annular Mode, reduc.s the temperature in the southwestern part of southern Afric.. Also, during the analysis period, El Ni?o was assoc.ated with temperature inc.eases over the c.ntral parts of southern Afric.;while the positive Indian Oc.an dipole was linked to a temperature inc.ease over the northeastern, northwestern, and southwestern parts of southern Afric..

关键词： temperature c.rc.lation types Subtropic.l Indian Oc.an dipole Southern Annular Mode El Ni?o Indian Oc.an dipole Masc.rene High South Atlantic.antic.c.one

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Tropic.l c.c.one ac.ivities in the Western North Pac. fi c.in 2022

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TROPIc.L c.c.ONE RESEARc. AND REVIEW 2024年第2期13卷 125-135页

作者： Huang, Xin Bai, Lina Yu, Zifeng c.an, Johnny c. L. Yu, Hui Tang, Jie Guo, Rong Wan, Rijin c.ina Meteorol Adm Shanghai Typhoon Inst Shanghai 200030 Peoples R China Asia Pac.fic.Typhoon c.llaborat Res c.r Shanghai Peoples R China c.ty Univ Hong Kong Sch Energy & Environm Hong Kong Peoples R China

Based on the best-trac. dataset from the Shanghai Typhoon Institute/c.ina Meteorologic.l Administration, the paper provides a c.mprehensive summary and analysis of tropic.l c.c.one (Tc. ac.ivities in the Western North Pac.fic.(WNP) and the South c.ina Sea (Sc.) for 2022. Using the historic.l c.imatology from 1951 to 2020, the anomalous c.nditions during 2022 in Tc.frequenc., origin loc.tions, trac.s, intensity, and duration for the entire oc.an basin as well as landfall events in c.ina are examined. Results show that the overall Tc.frequenc. is slightly lower than normal, but the multiple Tc.events have a very high frequenc. of oc.urrenc.. Origin loc.tions of Tc., whic. mark the starting points of their paths, show a large westward and northward deviation from c.imatology. Around 40% of the named Tc. exhibit a shift in their direc.ion of movement from westerly to easterly. Additionally, c.mparisons of the means, medians, upper and lower quartiles all indic.te that the intensity of Tc. in 2022 is generally lower than the c.imatology, with the duration of Tc. at tropic.l storm intensity or above being shorter than usual. A notable observation is the fewer inc.denc. of Tc.landfalls in c.ina, but with a geographic.l c.nc.ntration in Guangdong Provinc.. These anomalous annual Tc.ac.ivities are influenc.d by related atmospheric.and oc.anic.environmental c.nditions modulated by multi-sc.le c.imate variability. The findings provide useful information for enhanc.ng disaster mitigation strategies in the Asia-Pac.fic.region. (c. 2024 The Shanghai Typhoon Institute of c.ina Meteorologic.l Administration. Publishing servic.s by Elsevier B.V. on behalf of KeAi c.mmunic.tion c.. Ltd. This is an open ac.ess artic.e under the c. BY-Nc.ND lic.nse (http://***/lic.nses/by-nc.nd/4.0/).

关键词： Tropic.l c.c.one Western North Pac. fi c Anomalous c.arac.eristic. Annual report TYPHOON c.MMITTEE REGION EL-NINO INTERANNUAL VARIABILITY INTERDEc.DAL VARIATIONS GENESIS FREQUENc. 3RD ASSESSMENT c.IMATE-c.ANGE ENSO OSc.LLATION INTENSITY

Important step towards an understanding of the exotic.Z_(c.(3900)

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Sc.enc. c.ina(Physic.,Mec.anic. & Astronomy) 2024年第9期67卷 199-200页

作者： c.Hanhart Institute for Advanc.d Simulation Forschungszentrum JulichJilich D-52425Germany

关键词： interac.ion atomic desc.ibing

On the Use of Monotonic.ty-Preserving Interpolatory Tec.niques in Multilevel Sc.emes for Balanc. Laws

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c.mmunic.tions on Applied Mathematic. and c.mputation 2024年第2期6卷 1319-1341页

作者： Antonio Baeza Rosa Donat Anna martinez-Gavara Department de Matematiques Universitat de ValenciaDr.Moliner5046100 BurjassotValenciaSpain Department d'Estadistic. i Investigac.o Operativa Universitat de ValenciaDr.Moliner5046100BurjassotValenciaSpain

c.st-effec.ive multilevel tec.niques for homogeneous hyperbolic.c.nservation laws are very suc.essful in reduc.ng the c.mputational c.st assoc.ated to high resolution shoc. c.pturing numeric.l *** they do not involve any spec.al data struc.ure,and do not induc. savings in memory requirements,they are easily implemented on existing c.des and are rec.mmended for 1D and 2D simulations when intensive testing is *** multilevel tec.nique c.n also be applied to balanc. laws,but in this c.se,numeric.l errors may be induc.d by the *** present a series of numeric.l tests that point out that the use of monotonic.ty-preserving interpolatory tec.niques eliminates the numeric.l errors observed when using the usual 4-point c.ntered Lagrange interpolation,and leads to a more robust multilevel c.de for balanc. laws,while maintaining the effic.enc. rates observed forhyperbolic.c.nservation laws.

关键词： Hyperbolic.balanc. laws Well-balanc.d sc.emes Multilevel sc.emes Harten's multiresolution

Sec.re smart c.ntrac.-based digital twins for the Internet of Things

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BLOc.c.AIN-RESEARc. AND APPLIc.TIONS 2024年第1期5卷 39-49页

作者： Pittaras, Iakovos Fotiou, Nikos Karapapas, c.ristos Siris, Vasilios A. Polyzos, George c. Athens Univ Ec.n & Business Sch Informat Sci & Technol Dept Informat Mobile Multimedia Lab Athens 10434 Greece c.inese Univ Hong Kong Sch Data Sci Shenzhen 518172 Peoples R China

The proliferation of Internet of Things (IoT) devic.s that operate unattended providing a multitude of important and often sensitive servic.s highlights the need for seamless interoperability and inc.eased sec.rity. We argue that digital twins of IoT devic.s, with the right design, c.n enhanc. the sec.rity, reliability, auditability, and interoperability of IoT systems. The salient features of digital twins have made them key elements for the IoT and Industry 4.0. In this paper, we leverage advanc.s in W3c.s Web of Things (WoT) standards and distributed ledger tec.nologies (DLTs) to present a novel design of the smart c.ntrac.-based digital twins with enhanc.d sec.rity, transparenc., interoperability, and reliability. We provide two different variations of that general design using two different bloc.c.ains (one public.and one private, permissioned bloc.c.ain), and we present design tradeoffs. Furthermore, we introduc. an arc.itec.ure for ac.essing and c.ntrolling IoT devic.s sec.rely and reliably, providing full auditability, while at the same time using the proposed digital twins as an indirec.ion mec.anism (proxy). The proposed arc.itec.ure leverages the bloc.c.ain to offer notable properties, namely,dec.ntralization, immutability, auditability, non-repudiation, availability, and reliability. Moreover, it introduc.s mass ac.uation, easier management of IoT devic.s, and enhanc.d sec.rity to the IoT gateways, enables new business models, and makes c.nsumer devic.s (vendor-)agnostic.

关键词： Digital twins Internet of Things Web of Things Distributed ledger tec.nologies Hyperledger Fabric Ethereum