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npj Computational Materials 2023年第1期9卷 1204-1215页

作者： thomas A.R.purcel Matthias Scheffler Luca M.Ghiringhelli Christian Carbogno The NOMAD Laboratory at Fritz-Haber-Institut der Max-planck-Gesellschaft and IRIS-Adlershof of the Humboldt-Universität zu Berlin Faradayweg 4-6D-14195 BerlinGermany physics Department and IRIS Adlershof Humboldt Universität zu Berlin BerlinGermany

Reliable artificial-intelligence models have the potential to accelerate the discovery of materials with optimal properties for various applications,including superconductivity,catalysis,and *** in this field are often hindered by the scarcity and quality of available data and the significant effort required to acquire new *** such applications,reliable surrogate models that help guide materials space exploration using easily accessible materials properties are urgently ***,we present a general,data-driven framework that provides quantitative predictions as well as qualitative rules for steering data creation for all datasets via a combination of symbolic regression and sensitivity *** demonstrate the power of the framework by generating an accurate analytic model for the lattice thermal conductivity using only 75 experimentally measured *** extracting the most influential material properties from this model,we are then able to hierarchically screen 732 materials and find 80 ultra-insulating materials.

关键词： artificial thermal properties

predicting the potential distribution of invasive exotic species using GIS and information-theoretic approaches:A case of ragweed(Ambrosia artemisiifolia L.)distribution in China

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Chinese Science Bulletin 2007年第9期52卷 1223-1230页

作者： CHEN Hao CHEN LiJun thomas p. ALBRIGHT School of Remote Sensing Information Engineering Wuhan University Wuhan 430079 China National Geomatics Center of China Beijing 100080 China SAIC USGS Center for EROS Sioux Falls SD 57198 USA Department of Zoology University of Wisconsin-Madison WI USA

Invasive exotic species pose a growing threat to the economy,public health,and ecological integrity of nations worldwide. Explaining and predicting the spatial distribution of invasive exotic species is of great importance to prevention and early warning efforts. We are investigating the potential distribution of invasive exotic species,the environmental factors that influence these distributions,and the ability to predict them using statistical and information-theoretic approaches. For some species,detailed presence/absence occurrence data are available,allowing the use of a variety of standard statistical techniques. However,for most species,absence data are not available. presented with the challenge of developing a model based on presence-only information,we developed an improved logistic regres-sion approach using Information Theory and Frequency Statistics to produce a relative suitability map. This paper generated a variety of distributions of ragweed(Ambrosia artemisiifolia L.) from logistic regression models applied to herbarium specimen location data and a suite of GIS layers including climatic,topographic,and land cover information. Our logistic regression model was based on Akaike's Information Criterion(AIC) from a suite of ecologically reasonable predictor variables. Based on the results we provided a new Frequency Statistical method to compartmentalize habitat-suitability in the native range. Finally,we used the model and the compartmentalized criterion developed in native ranges to “project” a potential distribution onto the exotic ranges to build habitat-suitability maps.

关键词：外来入侵物种潜在分布预测信息论 GIS 豚草属

Information Divergence and the Generalized Normal Distribution:A Study on Symmetricity

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Communications in Mathematics and Statistics 2021年第4期9卷 439-465页

作者： thomas L.Toulias Christos p.Kitsos Department of Electrical and Electronics Engineering University of West AtticaCampus 1Egaleo12243 AthensGreece Department of Informatics and Computer Engineering University of West AtticaCampus 1Egaleo12243 AthensGreece

This paper investigates and discusses the use of information divergence,through the widely used Kullback–Leibler(KL)divergence,under the multivariate(generalized)γ-order normal distribution(γ-GND).The behavior of the KL divergence,as far as its symmetricity is concerned,is studied by calculating the divergence of γ-GND over the Student’s multivariate t-distribution and vice *** special cases are also given and ***,three symmetrized forms of the KL divergence,i.e.,the Jeffreys distance,the geometric-KL as well as the harmonic-KL distances,are computed between two members of the γ-GND family,while the corresponding differences between those information distances are also discussed.

关键词： Kullback-Leibler divergence Jeffreys distance Resistor-average distance Multivariateγ-order normal distribution Multivariate Student’s t-distribution Multivariate Laplace distribution

Evaluation of diverse classification approaches for land use/cover mapping in a Mediterranean region utilizing Hyperion data

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International Journal of Digital Earth 2014年第3期7卷 194-216页

作者： Alata Elatawneh Chariton Kalaitzidis George p.petropoulosc thomas Schneider Institute of Forest Management Technische Universität Muünchen(TUM)85354 FreisingGermany Department of Geoinformation in Environmental Management Mediterranean Agronomic Institute of Chania(MAICh)Chania 73100Greece INFOCOSMOS 13341 AthensGreece

Information on Earth’s land surface cover is commonly obtained through digital image analysis of data acquired from remote sensing *** this study,we evaluated the use of diverse classification techniques in discriminating land use/cover types in a typical Mediterranean setting using Hyperion *** this purpose,the spectral angle mapper(SAM),the object-based and the non-linear spectral unmixing based on artificial neural networks(ANNs)techniques were applied.A further objective had been to investigate the effect of two approaches for training sites selection in the SAM classification,namely of the pixel purity index(ppI)and of the direct selection of training points from the Hyperion imagery assisted by a QuickBird imagery and field-based training *** classification outperformed the other techniques with an overall accuracy of 83%.Sub-pixel classification based on the ANN showed an overall accuracy of 52%,very close to that of SAM(48%).SAM applied using the training sites selected directly from the Hyperion imagery supported by the QuickBird image and the field visits returned an increase accuracy by 16%.Yet,all techniques appeared to suffer from the relatively low spatial resolution of the Hyperion imagery,which affected the spectral separation among the land use/cover classes.

关键词： Hyperion Earth’s land use/cover mapping digital image analysis spectral angle mapper sub-pixel classification artificial neural networks Greece

Radio observations of the first three-months of Fermi AGN at 4.8 GHz

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Research in Astronomy and Astrophysics 2012年第2期12卷 147-157页

作者： Nicola Marchili thomas p.Krichbaum Lars Fuhrmann Anton Zensus Max-plank-Institut fr Radioastronomie

Using the Urumqi 25 m radio telescope, sources from the first three months of the Fermi-large area telescope detected active galactic nuclei （AGN） catalog with a declination of 〉 0° were observed in 2009 at 4.8 GHz. The radio flux density ap- peared to correlate with the γ-ray intensity. Intra-day variability （IDV） observations were performed in March, April and May 2009 for 42 selected γ-ray bright blazars, and ~60% of them showed evidence of flux variability at 4.8 GHz during the IDV observations. The IDV detection rate was higher than that in previous flat-spectrum AGN samples. IDV appeared more often in the very long baseline interferometry-core dominant blazars, and the non-IDV blazars showed relatively ＂steeper＂ spectral in- dices than the IDV blazars. pronounced inter-month variability was also found in two BL Lac objects： J0112＋2244 and J0238＋1636.

关键词： galaxies: active - quasars: general - radio continuum: galaxies -gamma-rays: observations

Synergistic Effect of Fullerene-Capped Gold Nanoparticles on Graphene Electrochemical Supercapacitors

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Advances in Nanoparticles 2013年第1期2卷 1-5页

作者： Virginia Yong H. thomas hahn Department of Materials Science and Engineering University of California Los Angeles USA

We report the synthesis of graphene/fullerene-capped gold nanoparticle nanocomposite film which was used to construct supercapacitor electrodes. The fullerene-based self-assembled monolayers on gold nanoparticles (AuNps) were attained via the fullerene(C60)-gold interaction. The fullerene-capped AuNps effectively separated the graphene sheets preventing aggregation. A synergistic effect was observed—the specific capacitance of graphene/fullerene-capped AuNp electrode is197 F/g, which is higher than that of graphene electrode (31 F/g), graphene/AuNp electrode (126 F/g), and graphene/fullerene electrode (118 F/g). The results render a novel route of synthesis and modification of graphene-based materials for the construction of electrochemical energy storage devices.

关键词： Fullerenes Gold Nanoparticles Graphene Supercapacitors Energy Storage Electrochemistry Self-Assembly Nanocomposites

Morphometric analysis of the drainage system and its hydrological implications in the rain shadow regions, Kerala, India

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Journal of Geographical Sciences 2011年第6期21卷 1077-1088页

作者： Jobin thomas Sabu JOSEpH K.p. THRIVIKRAMJI George ABE Department of Environmental Sciences University of Kerala Thiruvananthapuram-695 581 Kerala India Department of Geology University of Kerala Thiruvananthapuram-695 581 Kerala India Centre for Water Resources Development and Management Sub-Centre Kottayam Kerala India

The rain shadow regions requisite a comprehensive watershed development and management plan for sustainable water resources management. The pambar River Basin （pRB） lies on the rain shadow region of the southern Western Ghats, India, where climate showed marked intra-basin variation. A morphometric analysis was done to evaluate the drainage characteristics of pRB using topographical maps and digital elevation data. pRB was divided into eighteen 4th order basins （SB1-SB18）, distributed along various climatic gradients. Lower order streams mostly dominate pRB and drainage pattern is a function of relief and structure. The terrain is highly dissected and prone to soil erosion during heavy storms and the elongated shape of pRB enables easier flood management. The influence of climate on drainage characteristics was evidently emphasized in basin morphometry. Four distinctively different classes were identified based on the morphometric similarities. The significance of morphometric analysis on the hydrological characterization is discussed and the relevance of the present study in water harvesting has been explicated.

关键词： morphometry drainage basin pambar River Western Ghats India

Nanomechanical and Chemical Mapping of the Structure and Interfacial properties in Immiscible Ternary polymer Systems

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Chinese Journal of polymer Science 2021年第6期39卷 651-658,I0004页

作者： Hao-Xuan Li thomas pRussell Dong Wang State Key Laboratory of Organic-Inorganic Composites&Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China polymer Science and Engineering Department University of Massachusetts AmherstMassachusetts 01003United States Materials Sciences Division Lawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCalifornia 94720United States

It is a challenge to identify each phase in a multi-component polymer system and uniquely determine the interfacial properties between the different *** atomic force microscopy nanomechanical mapping(AFM-NM)and AFM-based infrared spectroscopy(AFM-IR),we identify each phase,visualize structural developments,and determine the interfacial properties in a blend of three polymers:high-density polyethylene(HDpE),polyamide(pA6)and poly(styrene-b-ethylene-co-butylene-b-styrene)(SEBS).Each phase can be identified from the Young’s modulus,along with the structural development within the phases before and after *** interfacial widths between HDpE/pA6,HDpE/SEBS and SEBS/pA6 were determined independently in one measurement from a Young’s modulus *** structural,mechanical property development and identity of the phases were determined by AFM-NM,while AFM-IR,providing complementary chemical information,identified interfacial reactions,showed the chemical affinity of a compatibilizer with the component phases,and mapped the distribution of the compatibilizer in the ternary polymer *** chemical,structural and interfacial information obtained by these measurements provide information that is essential for producing mechanically robust materials from incompatible mixtures of polymers.

关键词： AFM nanomechanical mapping AFM infrared spectroscopy Multi-component systems Interfacial structure Interfacial properties

Structural and luminescence enhancement properties of Eu^(3+)/Ag nanocrystallites doped SiO_2-TiO_2 matrices

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Journal of Rare Earths 2013年第5期31卷 441-448页

作者： Arun Kumar K V Revathy K p prathibha Vasudevan Sunil thomas Biju p R Unnikrishnan N V School of pure & Applied physics Mahatma Gandhi University

We reported here the structural and optical characterisation of silver nanocrystallites/Eu3＋：SiO2-TiO2 matrices synthesised through sol-gel route. Structural characterisations were done by using energy dispersive spectroscopy （EDX）, X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR）, atomic force microscope （AFM） and transmission electron microscopy （TEM） measurements and optical characterisations were performed by absorption and emission spectroscopy. The TEM and XRD measurements confirmed the presence of nanocrystals. A broad absorption band was observed due to surface plasmon resonance of silver nanocrystals. The effect of silver nanocrystals on the emission spectrum of Eu3＋ doped SiO2-TiO2 matrices was discussed. An attempt was made to explain this fluorescence enhancement by invoking phenomena such as energy transfer, asymmetry ratio, surface plasmon, surface roughness, crystallinity and grain boundary. Our analysis, based on the experimental results, suggested that all the phenomena except crystallinity and grain boundary had favourable effects on fluorescence enhancement. We also estimated the relevant parameters associated with the phenomena that affected the fluorescence emission from the Eu3＋ ions in the matrix. It was seen that the theoretical estimate of fluorescence enhancement agreed well with the experimental estimate.

关键词： sol-gel luminescence SiO2-TiO2 silver nanoparticles rare earths

STCF conceptual design report (Volume 1): physics & detector

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Frontiers of physics 2024年第1期19卷 1-154页

作者： M.Achasov X.C.Ai L.p.An R.Aliberti Q.An X.Z.Bai Y.Bai O.Bakina A.Barnyakov V.Blinov V.Bobrovnikov D.Bodrov A.Bogomyagkov A.Bondar I.Boyko Z.H.Bu F.M.Cai H.Cai J.J.Cao Q.H.Cao X.Cao Z.Cao Q.Chang K.T.Chao D.Y.Chen H.Chen H.X.Chen J.F.Chen K.Chen L.L.Chen p.Chen S.L.Chen S.M.Chen S.Chen S.p.Chen W.Chen X.Chen X.F.Chen X.R.Chen Y.Chen Y.Q.Chen H.Y.Cheng J.Cheng S.Cheng T.G.Cheng J.p.Dai L.Y.Dai X.C.Dai D.Dedovich A.Denig I.Denisenko J.M.Dias D.Z.Ding L.Y.Dong W.H.Dong V.Druzhinin D.S.Du Y.J.Du Z.G.Du L.M.Duan D.Epifanov Y.L.Fan S.S.Fang Z.J.Fang G.Fedotovich C.Q.Feng X.Feng Y.T.Feng J.L.Fu J.Gao Y.N.Gao p.S.Ge C.Q.Geng L.S.Geng A.Gilman L.Gong T.Gong B.Gou W.Gradl J.L.Gu A.Guevara L.C.Gui A.Q.Guo F.K.Guo J.C.Guo J.Guo Y.p.Guo Z.H.Guo A.Guskov K.L.Han L.Han M.Han X.Q.Hao J.B.He S.Q.He X.G.He Y.L.He Z.B.He Z.X.Heng B.L.Hou T.J.Hou Y.R.Hou C.Y.Hu H.M.Hu K.Hu R.J.Hu W.H.Hu X.H.Hu Y.C.Hu J.Hua G.S.Huang J.S.Huang M.Huang Q.Y.Huang W.Q.Huang X.T.Huang X.J.Huang Y.B.Huang Y.S.Huang N.Hüsken V.Ivanov Q.p.Ji J.J.Jia S.Jia Z.K.Jia H.B.Jiang J.Jiang S.Z.Jiang J.B.Jiao Z.Jiao H.J.Jing X.L.Kang X.S.Kang B.C.Ke M.Kenzie A.Khoukaz I.Koop E.Kravchenko A.Kuzmin Y.Lei E.Levichev C.H.Li C.Li D.Y.Li F.Li G.Li G.Li H.B.Li H.Li H.N.Li H.J.Li H.L.Li J.M.Li J.Li L.Li L.Li L.Y.Li N.Li p.R.Li R.H.Li S.Li T.Li W.J.Li X.Li X.H.Li X.Q.Li X.H.Li Y.Li Y.Y.Li Z.J.Li H.Liang J.H.Liang Y.T.Liang G.R.Liao L.Z.Liao Y.Liao C.X.Lin D.X.Lin X.S.Lin B.J.Liu C.W.Liu D.Liu F.Liu G.M.Liu H.B.Liu J.Liu J.J.Liu J.B.Liu K.Liu K.Y.Liu K.Liu L.Liu Q.Liu S.B.Liu T.Liu X.Liu Y.W.Liu Y.Liu Y.L.Liu Z.Q.Liu Z.Y.Liu Z.W.Liu I.Logashenko Y.Long C.G.Lu J.X.Lu N.Lu Q.F.Lü Y.Lu Y.Lu Z.Lu p.Lukin F.J.Luo T.Luo X.F.Luo Y.H.Luo H.J.Lyu X.R.Lyu J.p.Ma p.Ma Y.Ma Y.M.Ma F.Maas S.Malde D.Matvienko Z.X.Meng R.Mitchell A.Nefediev Y.Nefedov S.L.Olsen Q.Ouyang p.pakhlov G.pakhlova X.pan Y.pan E.passemar Y.p.pei H.p.peng L.peng X.Y.peng X.J.peng K.peters S.pivovarov E.pyata B.B.Qi Y.Q.Qi W.B.Qian Y.Qian C.F.Qiao J.J.Qin J.J.Qin L.Q.Qin X.S.Qin T.L.Qiu J.Rademacker C.F.Redmer H.Y.Sang Anhui University Hefei 230039China Beihang University Beijing 100191China Budker Institute of Nuclear physics Novosibirsk 630090Russia CAS Key Laboratory of Theoretical physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Cavendish Laboratory University of CambridgeJJ Thomson AveCambridge CB30HEUnited Kingdom Central China Normal University Wuhan 430079China Central South University Changsha 410083China China University of Geosciences Wuhan 430074China China University of Mining and Technology Xuzhou 221116China École polytechnique Fédérale de Lausanne(EpFL) LausanneSwitzerland Fudan University Shanghai 200433China Goethe University Frankfurt D-60325 Frankfurt am MainGermany Guangxi Normal University Guilin 541004China Guangxi Uninversity Nanning 530004China Hangzhou Institute for Advanced Study UCASHangzhou 310024China Hebei Normal University Shijiazhuang 050024China Hebei University Baoding 071002China Hefei University of Technology Hefei 230601China Helmholtz Institute Mainz Staudinger Weg 18D-55099 MainzGermany Henan Normal University Xinxiang 453007China Henan University Kaifeng 475004China High Energy physics Center Chung-Ang UniversitySeoul 06974Korea Higher School of Economy 11 pokrovsky Bulvar Moscow 109028Russia Huangshan University Huangshan 245000China Hubei University of Automotive Technology Shiyan 442002China Hunan Normal University Changsha 410081China Hunan University of Science and Technology Xiangtan 411201China Hunan University Changsha 410082China Indiana University BloomingtonIndiana 47405USA Inner Mongolia University Hohhot 010021China Institute of Advanced Science Facilities Shenzhen 518107China Institute of High Energy physics Chinese Academy of SciencesBeijing 100049China Institute of Modern physics Chinese Academy of SciencesLanzhou 730000China Institute of physics Academia SinicaTaipeiTaiwan 11529China Institute of Theoretical physics Chinese Academy of SciencesBeijing 100190China Jilin University Changch

The superτ-charm facility(STCF)is an electron–positron collider proposed by the Chinese particle physics *** is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of 0.5×10^(35) cm^(–2)·s^(–1) or *** STCF will produce a data sample about a factor of 100 larger than that of the presentτ-charm factory—the BEpCII,providing a unique platform for exploring the asymmetry of matter-antimatter(charge-parity violation),in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions,as well as searching for exotic hadrons and physics beyond the Standard *** STCF project in China is under development with an extensive R&D *** document presents the physics opportunities at the STCF,describes conceptual designs of the STCF detector system,and discusses future plans for detector R&D and physics case studies.

关键词： electron–positron collider tau-charm region high luminosity STCF detector conceptual design