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Linear nonadiabatic pulsation models of the double-mode Cepheid V371 Per

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Research in Astronomy and Astrophysics 2017年第6期17卷 11-16页

作者： Toshihito ishida Center for Astronomy Institute of Natural and Environmental Science University of Hyogo Sayo-cho Hyogo 679-5313 Japan

A recently found double-mode Cepheid with the shortest known period in our Galaxy and abnormal period ratio, V371 Per, is investigated by linear nonadiabatic pulsation models. V371 Per is likely to be crossing the instability strip for the first time, because the mass derived from pulsation models is larger than the evolution mass for the second or higher crossing objects. This result seems to support the conclusion obtained from spectroscopic observation. We also found that models with observed period and period ratio of V371 Per need to have mass and Teff in a narrow range which shifts as heavy element abundance Z changes. We have checked the agreement between Teffranges estimated observationally and derived from pulsation models using observational Z. We found that those ranges overlap marginally. We need more spectroscopic estimations of Teff and [Fe/H], and more photometric monitoring to estimate the evolutional period change for confirmation of our result.

关键词： stars: oscillations (including pulsations) - stars variables Cepheids - stars individual (V371 Per)

Velocity and Size of Droplets in Dense Region of Diesel Fuel Spray on Transient Needle Opening Condition

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Journal of Thermal Science 2005年第2期14卷 181-186页

作者： Hironobu UEKI Masahiro ishida Daisaku SAKAGUCHI Nagasaki University 1-14 Bunkyo-machi Nagasaki 852-8521JapanNagasaki University 1-14 Bunkyo-machiNagasaki 852-8521JapanNagasaki University 1-14 Bunkyo-machiNagasaki 852-8521Japan

In order to investigate the effect of transient needle opening on early stage of spray behavior, simultaneous measurements of velocity and size of droplet were conducted by a newly developed laser 2-focus velocimeter (L2F). The micro-scale probe of the L2F was consisted of two foci with a distance of 36μm. The tested nozzle had a single hole with a diameter of 0.2 mm. The measurements of injection pressure, needle lift, and crank angle were synchronized with the spray measurement by the L2F at the position 10 mm downstream from the nozzle exit. It has been clearly shown that the velocity and size of droplet increase with needle valve opening and that the probability density distribution of droplet size can be fitted to the Nukiyama-Tanasawa distribution under the transient needle opening condition.

关键词： droplet disintegration optical characterization laser 2-focus velocimeter.

Unified interpretation of scalegenesis in conformally extended standard models:a dynamical origin of Higgs portal

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Chinese Physics C 2020年第11期44卷 7-13页

作者： Hiroyuki ishida Shinya Matsuzaki Ruiwen Ouyang Theory Center IPNSKEKTsukubaIbaraki 305-0801Japan Center for Theoretical Physics and College of Physics Jilin UniversityChangchun 130012China Laboratory of High Energy and Computational Physics National Institute of Chemical Physics and BiophysicsRavala pst.1010143 TallinnEstonia

We present a universal interpretation of a class of conformal extended standard models that include Higgs portal interactions as realized in low-energy effective *** scale generation mechanism in this class(scalegenesis)arises along the(nearly)conformal/flat direction for breaking scale symmetry,where the electroweak symmetry-breaking structure arises similarly as in the standard model.A dynamical origin for the Higgs portal coupling can provide the discriminator for the low-energy“universality class,”to be probed in forthcoming collider experiments.

关键词： beyond standard model hidden QCD conformal symmetry

Phase Equilibria in Ni Rich Region of Ni-Al-Fe System

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 277-281页

作者： Chengchang Jia Kiyohito ishida Taiji Nishizawa Material Science and Engineering School University of Science and Technology BeijingBeijing 100083China Engineering faculty Tohoku UniversitySendai 980Japan

The phase equilibria between γ, α, γ' and β in the Ni-rich region of the Ni-Al-Fe system were investigated by the diffusion couple method and thermodynamic models. The thermodynamic parameters were assessed based on experimental results and thermodynamic data. Moreover, the system's phase equilibria from 900 to 1 300℃ were calculated with regular solution and sublattice models, and it is shown that the theoretic results agree well with experimental phase diagram data.

关键词： Superalloys

A backpropagation neural network improved by a genetic algorithm for predicting the mean radiant temperature around buildings within the long-term period of the near future

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Building Simulation 2022年第3期15卷 473-492页

作者： Yuquan Xie Yasuyuki ishida Jialong Hu Akashi Mochida Department of Architecture and Building Science Graduate School of EngineeringTohoku UniversityJapan Institute of Technology Tokyu ConstructionJapan

This study aimed to develop a neural network(NN)-based method to predict the long-term mean radiant temperature(MRT)around buildings by using meteorological parameters as training *** MRT dramatically impacts building energy consumption and significantly affects outdoor thermal *** NN-based long-term MRT prediction,two main restrictions must be overcome to achieve precise results:first,the difficulty of preparing numerous training datasets;second,the challenge of developing an accurate NN *** overcome these restrictions,a combination of principal component analysis(PCA)and K-means clustering was employed to reduce the training data while maintaining high prediction ***,three widely used NN models(feedforward NN(FFNN),backpropagation NN(BPNN),and BPNN optimized using a genetic algorithm(GA-BPNN))were compared to identify the NN with the best long-term MRT prediction *** performances of the tested NNs were evaluated using the mean absolute percentage error(MAPE),which was≤3%in each *** findings indicate that the training dataset was reduced effectively by the PCA and *** the three NNs,the GA-BPNN produced the most accurate results,with its MAPE being below 1%.This study will contribute to the development of fast and feasible outdoor thermal environment prediction.

关键词： backpropagation neural network principal component analysis mean radiant temperature K-means clustering genetic algorithm long-term prediction

Development of thermodynamic and kinetic databases in micro-soldering alloy systems and their applications

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Progress in Natural Science:Materials International 2011年第2期21卷 97-110页

作者： Ikuo OHNUMA Ryosuke KAINUMA Kiyohito ishida Department of Materials Science Graduate School of EngineeringTohoku UniversitySendai 980-8579Japan

Recent progress in the development of thermodynamic and kinetic databases of micro-soldering alloys,which were constructed within the framework of the Thermo-Calc and DICTRA software,was ***,a thermodynamic tool, ADAMIS(alloy database for micro-solders) was developed by combining the thermodynamic databases of micro-solders with Pandat,a multi-component phase diagram calculation software *** contains 11 elements,namely,Ag,Al,Au,Bi,Cu, In,Ni,Sb,Sn,Zn and Pb,and can handle all combinations of these elements in the whole composition *** obtained thermodynamic and kinetic databases can not only provide much valuable thermodynamic information such as phase equilibria and phase fraction,but also shows the kinetics and the evolution of microstructures when they are combined with some appropriate software programs and models,such as the phase field method and ADSTEFAN *** the viewpoints of computational thermodynamics and kinetics,some technical examples were given to demonstrate the great utility of these databases for the applications in the development of micro-soldering *** databases are expected to be powerful tools for the development of micro-solders and Cu substrate materials,as well as for promoting the understanding of interfacial phenomena and microstructure evolution between solders and substrates in electronic packaging technology.

关键词： micro-soldering alloys thermodynamics kinetics

Factors other than fibrosis that increase measured shear wave velocity

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World Journal of Gastroenterology 2022年第46期28卷 6512-6521页

作者： Hiroko Naganuma Hideaki ishida Department of Gastroenterology Yokote Municipal HospitalYokote 013-8602Japan Department of Gastroenterology Akita Red Cross HospitalAkita 010-1495Japan

Shear wave elastography(SWE)is now becoming an indispensable diagnostic tool in the routine examination of liver *** particular,accuracy is required for shear wave propagation velocity measurement,which is directly related to diagnostic *** is generally accepted that the liver shear wave propagation velocity reflects the degree of fibrosis,but there are still few reports on other factors that increase the shear wave propagation *** this study,we reviewed such factors in the literature and examined their *** SWE measures propagation velocity based on the assumption that the medium has a homogeneous structure,uniform density,and is purely ***,the measurement is subject to *** other(confounding)factors that we routinely experience are primarily:(1)Conditions that appear to increase the viscous component;and(2)Conditions that appear to increase tissue ***,the former includes acute hepatitis,congested liver,biliary obstruction,etc,and the latter includes diffuse infiltration of malignant cells,various storage diseases,tissue necrosis,*** any case,it is important to evaluate SWE in the context of the entire clinical picture.

关键词： Liver Shear wave elastography Propagation velocity Viscoelasticity Artifact Ultrasound

Mixed layer in the Sea of Japan:numerical simulation andlong-term data analysis

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Acta Oceanologica Sinica 2005年第1期24卷 76-85页

作者： TRUSENKOVA Olga KHRAPCHENKOV Fyodor ishida.ha.ime V.I.Il'ichev Pacific Oceanological Institute Russian Academy of Sciences Vladivostok 690041 RussiaV.I.Il'ichev Pacific Oceanological Institute Russian Academy of Sciences Vladivostok 690041 RussiaFaculty of Engineering Kanazawa University Kanazawa 920-8667 Japan

Seasonal variation and topography of the mixed layer in the Sea of Japan are studied by comparison of results from long-term observation data analysis and from numerical simulation with the MHI oceanic model (Shapiro. 1998. Marine Hydrophysical Journal, 6: 26-40). The data are retrieved from Oceanographic A tlas of the Bering Sea, Okhotsk Sea, and Japan/East Sea (Rostov, Rostov, Dmitrieva, et al. 2003. Pacific Oceanography, 1(1):70-72). The simulated and long-term patterns are compared. An impact of surface buoyancy flux, wind, and convergence/divergence of surface currents upon the mixed layer in the Sea of Japan is analyzed.

关键词： numerical modeling circuktion of the Sea of Japan mixed layer depth seasonal variation spatial patterns

Gravitational wave footprints from Higgs-portal scalegenesis with multiple dark chiral scalars

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Chinese Physics C 2024年第4期48卷 209-221页

作者： He-Xu Zhang Shinya Matsuzaki Hiroyuki ishida Center for Theoretical Physics and College of Physics Jilin UniversityChangchun 130012China Center for Liberal Arts and Sciences Toyama Prefectural UniversityToyama 939-0398Japan

We discuss the gravitational wave(GW)spectra predicted from the electroweak scalegenesis of the Higgs portal type with a large number of dark chiral flavors,which many flavor QCD would underlie and give the dynamical explanation of the negative Higgs portal coupling required to trigger the electroweak symmetry *** employ the linear-sigma model as the low-energy description of dark many flavor QCD and show that the model undergoes ultra-supercooling due to the produced strong first-order thermal phase transition along the(approximately realized)flat direction based on the Gildener-Weinberg *** through evaluation of the bubble nucleation/percolation,we address the reheating and relaxation processes,which are generically non-thermal and *** the reheating epoch in terms of the e-folding number,we propose proper formulae for the redshift effects on the GW frequencies and signal *** then turns out that the ultra-supercooling predicted from the Higgs-portal scalegenesis generically yields none of GW signals with the frequencies as low as nano Hz,unless the released latent heat is transported into another sector other than reheating the ***,models of this class prefer to give the higher frequency signals and still keeps the future prospected detection sensitivity,like at LISA,BBO,and DECIGO,*** also find that with large flavors in the dark sector,the GW signals are made further smaller and the peak frequencies *** phenomenological consequences related to the multiple chiral scalars include the prediction of dark pions with the mass much less than TeV scale,which is also briefly addressed.

关键词： gravitational wave electroweak scalegenesis many flavor QCD