Updated on 2026/04/25

写真a

 
OKAZE TSUBASA
 
Organization
School of Environment and Society Associate Professor
Title
Associate Professor
External link

Degree

  • 博士(工学) ( 東北大学 )

Research Interests

  • 風工学

  • 雪工学

  • 数値流体力学

  • 都市環境工学

Research Areas

  • Social Infrastructure (Civil Engineering, Architecture, Disaster Prevention) / Architectural environment and building equipment

Education

  • Tohoku University   Graduate School of Engineering   Department of Architecture and Building Science

    2010.4 - 2012.3

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  • Tohoku University   Graduate School of Engineering   Department of Architecture and Building Science

    2006.4 - 2008.3

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  • Tohoku University   Faculty of Engineering   Department of Architecutre

    2002.4 - 2006.3

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Research History

  • Institute of Science Tokyo   School of Environment and Society   Associate Professor

    2024.10

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  • Tokyo Institute of Technology   Associate Professor

    2016.3 - 2024.9

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  • Tohoku University   Graduate School of Engineering Department of Architecture and Building Science   Assistant Professor

    2013.4 - 2016.2

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  • Tohoku University   JSPS Research Fellow (PD)

    2012.4 - 2013.3

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  • Tohoku University   JSPS Research Fellow (DC1)

    2010.4 - 2012.3

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  • Tohoku University   Graduate School of Engineering   Research Assistant

    2009.3 - 2010.3

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  • NTTファシリティーズ

    2008.4 - 2009.2

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Professional Memberships

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Committee Memberships

  • The 8th International Symposium on Computational Wind Engineering   Scientific Committee  

    2025.9   

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    Committee type:Academic society

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  • 日本建築学会   関東支部研究運営委員会 委員長  

    2025.4   

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    Committee type:Academic society

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  • Scientific Reports   Editorial Board Members  

    2025.4   

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  • SBE25 TOKYO Sustainable Built Environment Conference 2025 in Tokyo   Scientific Committee  

    2024.12 - 2025.9   

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    Committee type:Academic society

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  • 雪氷研究大会   雪氷研究大会(2025・津)実行委員  

    2024.9 - 2025.12   

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    Committee type:Academic society

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  • 日本建築学会   風環境予測・評価体系化検討WG 主査  

    2024.4   

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    Committee type:Academic society

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  • 日本雪工学会   理事  

    2020.6   

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    Committee type:Academic society

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  • 日本風工学会   代表委員  

    2017.12   

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    Committee type:Academic society

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  • 建築環境設計支援協会   理事  

    2017.4   

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    Committee type:Academic society

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  • 東京都港区   環境影響調査審査会 副会長  

    2017.4   

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    Committee type:Municipal

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  • 日本建築学会   関東支部環境工学専門研究委員会 委員  

    2016.4   

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    Committee type:Academic society

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  • 日本建築学会   屋外空気環境小委員会 委員  

    2015.4   

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    Committee type:Academic society

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  • 日本建築学会   気候変動による災害防止に関する特別調査委員会  

    2014.4 - 2016.3   

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    Committee type:Academic society

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  • 検証用ベンチマーク実施WG(日本建築学会 屋外空気環境小委員会の傘下)   幹事  

    2013   

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    Committee type:Academic society

    検証用ベンチマーク実施WG(日本建築学会 屋外空気環境小委員会の傘下)

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  • 日本雪氷学会   吹雪分科会 幹事  

    2012.9   

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  • 日本建築学会 GCMを活用した近未来標準気象データ作成WG   委員  

    2012.4 - 2014.3   

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    Committee type:Academic society

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  • 日本雪工学会   編集委員会 幹事  

    2010.7 - 2016.6   

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    Committee type:Academic society

    日本雪工学会誌 編集委員会

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  • CASBEE 研究開発委員会   ヒートアイランド検討小委員会 幹事  

    2009   

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    Committee type:Academic society

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  • 日本建築学会 都市・建築空間における雪氷災害対策に関する特別研究委員会   委員  

    2007 - 2008   

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    Committee type:Academic society

    日本建築学会 都市・建築空間における雪氷災害対策に関する特別研究委員会

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Papers

  • Comprehensive Experimental Database for Validating CFD Simulations in Urban Wind Environment: Benchmark Cases Curated by the Architectural Institute of Japan Reviewed

    Hideki Kikumoto, Tsubasa Okaze, Ryuichiro Yoshie, Takumi Tachibana, Takeshi Ishihara, Yoshitami Nonomura, Nobuyoshi Kiyota, Hiroaki Kondo, Akashi Mochida, Yoshihide Tominaga

    JAPAN ARCHITECTURAL REVIEW   9 ( 1 )   2026.3

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    Publishing type:Research paper (scientific journal)   Publisher:Wiley  

    ABSTRACT

    Reliable validation data are essential for ensuring the accuracy and applicability of computational fluid dynamics (CFD) simulations used to analyze urban wind environments. This data paper presents a comprehensive experimental database curated by a working group of the Architectural Institute of Japan (AIJ) to support CFD validation. The database includes 13 benchmark cases, ranging from simplified building geometries to complex urban configurations, with measurements of wind velocity, turbulence, pollutant (tracer) concentration, and temperature under various flow and thermal conditions. The experimental data were compiled from both existing and newly conducted wind‐tunnel and field measurements, collected through collaborations among universities, research institutes, and industry. These cases provide a standardized and versatile basis for evaluating CFD model performance, facilitating uncertainty assessment, inter‐model comparison, and best‐practice development. Each case includes detailed information on experimental setups and measurement techniques to aid reproducibility and application. All datasets are publicly available through open data repositories and have already been widely used in numerous validation studies worldwide. This data paper aims to encourage continued use and broader dissemination of these benchmark cases, thereby enhancing the reliability and credibility of CFD predictions in urban wind and pollutant dispersion analyses.

    DOI: 10.1002/2475-8876.70083

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    Other Link: https://onlinelibrary.wiley.com/doi/full-xml/10.1002/2475-8876.70083

  • AIJ guidelines on the applications of large-eddy simulation to pedestrian wind environment: Recommendations and validation benchmarks Reviewed

    Tsubasa Okaze, Hideki Kikumoto, Naoki Ikegaya, Keisuke Nakao, Hiroki Ono, Keigo Nakajima, Masashi Imano, Takamasa Hasama, Yuichi Tabata, Takeshi Kishida, Ryuichiro Yoshie, Yoshihide Tominaga

    Journal of Wind Engineering and Industrial Aerodynamics   269   106321 - 106321   2026.2

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    Authorship:Lead author, Corresponding author   Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.jweia.2025.106321

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  • Data-driven accuracy enhancement of cup anemometers in urban pedestrian-level wind measurements combining large-eddy simulation database Reviewed

    Rongmao Li, Hongyuan Jia, Chaoyi Hu, Xiang Wang, Tsubasa Okaze, Hideki Kikumoto

    Building and Environment   2025.9

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    Publishing type:Research paper (scientific journal)  

    DOI: 10.1016/j.buildenv.2025.113417

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  • Turbulent characteristics in the atmospheric boundary layer under neutral and unstable thermal stratifications based on LES Reviewed

    Yezhan Li, Tsubasa Okaze, Naoki Ikegaya

    Journal of Wind Engineering and Industrial Aerodynamics   263   106126 - 106126   2025.8

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    Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.jweia.2025.106126

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  • COST-BENEFIT ANALYSIS OF HEAT ISLAND MITIGATION STRATEGY (PART 1) : EVALUATION OF HIGH-REFLECTION TREATMENT ON BUILDING ROOF SURFACES IN OSAKA PREFECTURE Reviewed

    Natsu TERUI, Tsubasa OKAZE, Tomohiko IHARA, Daisuke NARUMI

    Journal of Environmental Engineering (Transactions of AIJ)   90 ( 833 )   326 - 337   2025.7

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:Architectural Institute of Japan  

    DOI: 10.3130/aije.90.326

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  • Effective grid scale of large-eddy simulations in various advection schemes using airflow around 1:1:2 block model Reviewed

    T. Tong, T. Okaze, N. Ikegaya

    Building and Environment   2025.7

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    Publishing type:Research paper (scientific journal)  

    DOI: 10.1016/j.buildenv.2025.113060

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  • Investigating convective heat transfer coefficients of building surfaces under different thermal stratifications with non-isothermal inflow boundary conditions

    Yezhan Li, Tsubasa Okaze

    Building and Environment   279   113059 - 113059   2025.7

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    Authorship:Last author   Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.buildenv.2025.113059

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  • Optimizing non-isothermal turbulent inflow generation using precursor method: A sensitivity study Reviewed

    Yezhan Li, Tsubasa Okaze

    Building and Environment   269   112465 - 112465   2025.2

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    Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.buildenv.2024.112465

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  • Field-based investigation of snow-drift flux increases in blowing snow and application to mapping of short-term visibility reduction using mesoscale meteorological simulation Reviewed

    Tsubasa Okaze, Risa Kawashima, Takeru Ito, Satoshi Omiya, Hirofumi Niiya, Kouichi Nishimura

    Journal of Wind Engineering and Industrial Aerodynamics   257   105989 - 105989   2025.2

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    Authorship:Lead author, Corresponding author   Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.jweia.2024.105989

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  • EVALUATION AND UNCERTAINTY ANALYSIS OF PEAK WIND SPEED STATISTICS AT PEDESTRIAN LEVEL AROUND AN ISOLATED BUILDING MODEL USING LARGE-EDDY SIMULATION Reviewed

    Hideki KIKUMOTO, Tsubasa OKAZE, Naoki IKEGAYA, Yoshihide TOMINAGA

    Journal of Environmental Engineering (Transactions of AIJ)   90 ( 827 )   35 - 44   2025.1

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:Architectural Institute of Japan  

    DOI: 10.3130/aije.90.35

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  • Comparisons of experimentally and numerically determined statistics for predicting low-occurrence wind speeds around a 1:1:2 block model Reviewed

    T. Tong, Y. Li, W. Wang, M.F. Mohamad, T. Okaze, N. Ikegaya

    Building and Environment   267   112201 - 112201   2025.1

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    Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.buildenv.2024.112201

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  • INFLUENCE OF A GROUP OF IGUNE ROWS ORTHOGONAL TO PREVAILING WIND DIRECTION ON WINDBREAK EFFECTS WITHIN A RURAL VILLEGE Reviewed

    南健斗, 水田瑛人, 米澤千夏, 大風翼

    風工学研究論文集   28   120 - 128   2024.12

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    Authorship:Last author   Language:Japanese  

    DOI: 10.14887/windengresearch.28.0_120

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  • URANS simulation of pollutant dispersion within a simplified buildings array: influence of k-ε model modification reproducing periodic large-scale fluctuations Reviewed

    Xinyi Li, Tsubasa Okaze

    Wind Engineering Research   28   100 - 109   2024.12

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    Authorship:Last author   Language:English  

    DOI: 10.14887/windengresearch.28.0_100

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  • POD に基づく 2 次元樹林モデル周辺の乱流変動に伴う逆流形成要因の検討 Reviewed

    水田瑛人, 南 健斗, 大風 翼

    風工学研究論文集   28   136 - 144   2024.12

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    DOI: 10.14887/windengresearch.28.0_136

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  • 吉川 峻平, 大風 翼, 高野 靖, 西嶋 一欽 Reviewed

    28   48 - 54   2024.12

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  • 熱的中立環境下の人工気候室実験に基づく風の心地よさ感に関わる脳領域の推定 Reviewed

    東野莉奈, 中村隆斗, 本江一紘, 玄英麗, 吉村奈津江, 大風翼

    風工学研究論文集   28   110 - 119   2024.12

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  • パーシステントホモロジーを用いた風の道抽出法の検討 Reviewed

    誉田優太, 藤井隼平, 大風翼

    風工学研究論文集   28   129 - 135   2024.12

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    Authorship:Last author   Language:Japanese  

    DOI: 10.14887/windengresearch.28.0_129

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  • Extrapolating low-occurrence strong wind speeds at pedestrian levels using artificial neural networks trained by a single turbulent dataset Reviewed

    Y. Li, W. Wang, T. Okaze, N. Ikegaya

    Sustainable Cities and Society   115   105837 - 105837   2024.11

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    Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.scs.2024.105837

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  • URANS simulation reproducing large-scale periodic fluctuations and their impact on pollutant dispersion around an isolated 1:1:2 building Reviewed

    Xinyi Li, Tsubasa Okaze

    Building and Environment   265   111872 - 111872   2024.11

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    Authorship:Last author   Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.buildenv.2024.111872

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  • Application of polyhedral meshes in large-eddy simulation of building array flow fields within neutral and unstable boundary layers Reviewed

    Yezhan Li, Tsubasa Okaze

    Building and Environment   263   111846 - 111846   2024.9

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    Authorship:Last author   Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.buildenv.2024.111846

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  • Cross-sensor domain adaptation for data-driven correction of pedestrian level wind measurement in urban environments using cup anemometers Reviewed

    Rongmao Li, Hideki Kikumoto, Hongyuan Jia, Xiang Wang, Tsubasa Okaze

    Sustainable Cities and Society   2024.7

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    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1016/j.scs.2024.105430

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  • Comparison of various statistical methods for estimating extreme wind speed at the pedestrian level in idealized and actual urban areas Reviewed

    Wei Wang, Takeru Sekikawa, Tsubasa Okaze, Naoki Ikegaya

    Journal of Wind Engineering and Industrial Aerodynamics   250   2024.7

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    Publishing type:Research paper (scientific journal)  

    DOI: 10.1016/j.jweia.2024.105778

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  • Classification of pleasantness of wind by electroencephalography Reviewed

    Yasuhisa Maruyama, Ryuto Nakamura, Shota Tsuji, Yingli Xuan, Kunio Mizutani, Tsubasa Okaze, Natsue Yoshimura

    PLOS ONE   19 ( 2 )   e0299036 - e0299036   2024.2

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    Publishing type:Research paper (scientific journal)   Publisher:Public Library of Science (PLoS)  

    Thermal comfort of humans depends on the surrounding environment and affects their productivity. Several environmental factors, such as air temperature, relative humidity, wind or airflow, and radiation, have considerable influence on the thermal comfort or pleasantness; hence, these are generally controlled by electrical devices. Lately, the development of objective measurement methods for thermal comfort or pleasantness using physiological signals is receiving attention to realize a personalized comfortable environment through the automatic control of electrical devices. In this study, we focused on electroencephalography (EEG) and investigated whether EEG signals contain information related to the pleasantness of ambient airflow reproducing natural wind fluctuations using machine learning methods. In a hot and humid artificial climate chamber, we measured EEG signals while the participants were exposed to airflow at four different velocities. Based on the reported pleasantness levels, we performed within-participant classification from the source activity of the EEG and obtained a classification accuracy higher than the chance level using both linear and nonlinear support vector machine classifiers as well as an artificial neural network. The results of this study showed that EEG is useful in identifying people’s transient pleasantness when exposed to wind.

    DOI: 10.1371/journal.pone.0299036

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  • Detector configuration optimization based on wind tunnel tests using normalized adjoint concentration gradient for urban spatial source parameters estimation Reviewed

    Fuyu Wang, Xuanyi Zhou, Hideki Kikumoto, Tsubasa Okaze

    Building and Environment   248   111094 - 111094   2024.1

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    Authorship:Last author   Publishing type:Research paper (scientific journal)  

    DOI: 10.1016/j.buildenv.2023.111094

    Web of Science

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  • Co-creation with local governments and ski resorts to generate scientific information that contributes to ski resort avalanche safety management Reviewed

    Satoru YAMAGUCHI, Yoichi ITO, Takahiro TANABE, Kouichi NISHIMURA, Satoru ADACHI, Sojiro SUNAKO, Yoshihiko SAITO, Tsubasa OKAZE, Hirofumi NIIYA, Kae TSUNEMATSU, Hiraku NISHIMORI

    Bulletin of Glaciological Research   42   9 - 17   2024

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    Publishing type:Research paper (scientific journal)   Publisher:Japanese Society of Snow and Ice  

    DOI: 10.5331/bgr.23r02

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  • Feasibility of eolian sound for urban wind speed estimation Reviewed

    Shunpei Yoshikawa, Kazuyoshi Nishijima, Tsubasa Okaze, Yasushi Takano

    JAPAN ARCHITECTURAL REVIEW   7 ( 1 )   2023.12

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    Publishing type:Research paper (scientific journal)   Publisher:Wiley  

    Abstract

    Wind‐speed measurement is crucial in designing wind‐resistant buildings and controlling the wind environment in urban areas. However, the current methods of measuring wind speed, such as anemometers and Doppler lidar, are associated with high costs. This study investigated an alternative approach to measuring wind speed using the eolian sound emitted from cylindrical objects in urban settings, such as electrical cables. The proposed method relies on a relationship between the frequency of Karman vortex generation, which gives rise to eolian sound, and wind speed, considering the diameter of a cylindrical object. This study addressed 2 research questions: (1) the possibility of capturing and identifying the eolian sound emitted from a cylindrical object using a generic recording device and whether the peak frequency of the recorded sound aligns with the theoretically predicted frequency; (2) the feasibility of estimating the direction of the eolian sound source to identify the object responsible for the sound emission. The authors conducted a series of experiments involving artificially generated eolian sound in an outdoor environment and analyzed the recorded sound signals. The analysis results were encouraging, confirming positive responses to both research questions. These results indicate the potential for a novel method capable of estimating wind speed.

    DOI: 10.1002/2475-8876.12424

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  • Statistical analysis for predicting low-occurrence strong wind speeds at the pedestrian level in an actual urban case Reviewed

    Wei Wang, Tsubasa Okaze

    Building and Environment   244   110781 - 110781   2023.10

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    Authorship:Last author   Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.buildenv.2023.110781

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  • Appropriate Momentum Provision for Numerical Simulations of Horizontally Homogeneous Urban Canopies Using Periodic Boundary Conditions Reviewed

    Toshiki Sanemitsu, Naoki Ikegaya, Tsubasa Okaze, John J. Finnigan

    Boundary-Layer Meteorology   188 ( 3 )   485 - 522   2023.8

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    Publishing type:Research paper (scientific journal)   Publisher:Springer Science and Business Media LLC  

    DOI: 10.1007/s10546-023-00823-z

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    Other Link: https://link.springer.com/article/10.1007/s10546-023-00823-z/fulltext.html

  • Transfer learning strategy for data-driven correction of wind measurement around buildings using cup anemometers Reviewed

    Rongmao Li, Hideki Kikumoto, Hongyuan Jia, Tsubasa Okaze

    Building and Environment   241   110499 - 110499   2023.8

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    Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.buildenv.2023.110499

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  • Evaluation of polyhedral mesh performance for large-eddy simulations of flow around an isolated building within an unstable boundary layer Reviewed

    Yezhan Li, Wei Wang, Tsubasa Okaze

    Building and Environment   235   110207 - 110207   2023.5

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    DOI: 10.1016/j.buildenv.2023.110207

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  • Comparing Weibull distribution method and Gram–Charlier series method within the context of estimating low-occurrence strong wind speed of idealized building cases Reviewed

    Wei Wang, Naoki Ikegaya, Tsubasa Okaze

    Journal of Wind Engineering and Industrial Aerodynamics   236   105401 - 105401   2023.5

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    Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.jweia.2023.105401

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  • Review of Wind Resistant Design for Tiled Roofs and Publication of New CFD Guidebook for Urban Wind Environment: Japan Country Report 2021 Reviewed

    Hitomitsu Kikitsu, H. Kikumoto, Y. Takadate, Y. Okuda, T. Okaze, Y. Tominaga

    CONSTRUCTION   2 ( 2 )   114 - 125   2022.12

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    Publishing type:Research paper (scientific journal)   Publisher:Universiti Malaysia Pahang Al-Sultan Abdullah Press (UMPSA Press)  

    This paper introduces recent activities related to the structural and environmental engineering in Japan. Part 1 in this paper illustrates outline of recent research and standardization related to ensuring wind resistant performance of tiled roofs. We introduce the results of damage survey on tiled roofs caused by Typhoon Faxai in 2019, which was conducted by National Institute for Land and Infrastructure Management and Building Research Institute in collaboration with clay roof tile industry organization. Then, the outline of the wind load calculation method stipulated in the Building Standards Law and the amended Notification for roof tiles is illustrated. In addition, “Guideline for Standard Structural Design/Construction for Tiled Roof” was revised in July 2021 as a supplement to the law. The outline of monotonous pull-up test and the standard specifications, both of which are newly added to the revised version of the Guideline, are also introduced. These activities are aimed to reduce structural vulnerability of tiled roofs, based on the lessons learned from the damage caused by the typhoon. In Part 2, we introduce activities to promote the appropriate use of computational fluid dynamics (CFD) in wind environment prediction. A working group within the Architectural Institute of Japan compiled a new CFD guidebook and guidelines for urban wind environment prediction, mainly aiming to include the application of large-eddy simulation to pedestrian-level wind problems or dispersion problems relating to concentration and temperature in cities. Reflecting the latest domestic and international research trends and the WG’s validation works, achievements of their activities were published as “Guidebook for CFD Predictions of Urban Wind Environment” (2020, in Japanese), papers in international journals, and an extended experimental database for verification and validation of analysis codes.

    DOI: 10.15282/construction.v2i2.7421

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  • Analysis of fluctuation of visibility distribution for increased snow-drift flux due to turbulent fluctuation under blowing snow without snowfall Reviewed

    Risa Kawashima, Satoshi Omiya, Hirofumi Niiya, Kouichi Nishimura, Tsubasa Okaze

    Wind Engineering Research   27   1 - 10   2022.12

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    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.14887/windengresearch.27.0_48

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  • ESTIMATION OF LOW-OCCURRENCE WIND SPEED AT THE PEDESTRIAN LEVEL AROUND AN ISOLATED BUILDING: COMPARISON OF WEIBULL DISTRIBUTION METHOD AND GRAM.CHARLIER SERIES METHOD Reviewed

    Wei WANG, Taishi KAWAMINAMI, Koki SETA, Naoki IKEGAYA, Tsubasa OKAZE

    Wind Engineering Research   27   28 - 37   2022.12

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    Authorship:Last author   Language:English  

    DOI: 10.14887/windengresearch.27.0_28

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  • Performance of polyhedral mesh in large-eddy simulation of flow and temperature fields within a cubic array in unstable boundary layer Reviewed

    Yezhan LI, Tsubasa OKAZE

    Wind Engineering Research   27   38 - 47   2022.12

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  • APPLICABILITY OF A PLANT CANOPY MODEL IN LARGE-EDDY SIMULATION WITH A 0-EQUATION MODEL CONSIDERING ONLY DRAG FORCE TERM FOR PEDESTRIAN WIND ENVIRONMENTS Reviewed

    MINAMI Kento, YONEZAWA Chinatsu, OKAZE Tsubasa

    Wind Engineering Research   27   19 - 27   2022.12

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    Authorship:Last author   Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:Japan Association for Wind Engineering  

    This study examined the applicability of a plant canopy model in large-eddy simulation (LES) with a 0-equation subgrid scale (SGS) model considering only drag force term for pedestrian wind environment (PWE) by comparing with a 1-equation model reproducing the increase in SGS kinetic energy kSGS within the tree crown. The two simulations for the flows around a two-dimensional row of trees provided in the benchmark case by Architectural Institute of Japan and actual homestead trees were conducted. In the benchmark case, the 1-equation model reproduced similar results to the 0-equation model due to the small increase in kSGS In addition, the 0-equation model still reproduced the results of field observation in an actual homestead trees case. The effect of increasing kSGS on the mean wind speed, grid scale turbulent kinetic energy, and probability density function of wind velocity fluctuation became small under the spatial resolutions generally used for the simulation for PWE.

    DOI: 10.14887/windengresearch.27.0_19

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  • Estimating low-occurrence wind speeds from mean velocity and turbulent kinetic energy: Development of statistical method and validation with idealized cases Reviewed

    Wei Wang, Tsubasa Okaze

    Building and Environment   224   109499 - 109499   2022.10

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    Authorship:Last author   Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.buildenv.2022.109499

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  • Development and performance evaluation of a micro anaerobic digestion system for household use Reviewed

    Tsubasa Okaze, Chika Tada

    JAPAN ARCHITECTURAL REVIEW   5 ( 4 )   644 - 648   2022.9

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    Abstract

    Currently, sustainable societies require a reduction in general and food waste discharge, which is a major environmental problem. As food waste contains a high moisture content, anaerobic digestion is an effective way to recycle food waste that contains large amounts of moisture. While 70% of industrial food waste is recycled, only approximately 20% of household waste is recycled in Japan. In this study, we developed a micro anaerobic digestion system with a capacity of 30 L and evaluated its basic performance by simulating a daily use situation. Biogas was produced, containing the same amount of methane as other systems. Although no mixing in the fermenter was done, the production efficiency of methane reached approximately at least 60% of the theoretical value of methane gas production for the chemical oxygen demand of the input food waste.

    DOI: 10.1002/2475-8876.12289

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    Other Link: https://onlinelibrary.wiley.com/doi/full-xml/10.1002/2475-8876.12289

  • A Study of Effects of Wind Speed Reduction by “Igune” as Homestead Treesaround Rural House in Osaki Koudo based on Large-Eddy Simulation Reviewed

    MINAMI Kento, YONEZAWA Chinatsu, OKAZE Tsubasa

    Journal of the Japanese Agricultural Systems Society   38 ( 2 )   37 - 42   2022.7

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    Homestead trees are a group of trees surrounding houses that have been maintained for a variety of functions in housing and human life. For example, there are functions for controlling the environment of outdoor spaces, such as windbreaks and solar radiation shielding. In addition, for the role of living materials, woods are used as a building material and fallen leaves are used as a fuel. In the past, homestead trees existed along with houses in many cases. For this reason, the homestead trees, called various names depending on the characteristics of the location, have been found all over Japan since long ago. However, due to the development of cities and changes in lifestyles, the number of homestead trees has been decreasing since the 1970s. This study aims to quantitatively evaluate the windbreak effects of traditional homestead trees in Miyagi Prefecture called "Igune". The flow field around a scattered village-style rural house with 10 m high Igune on the prevailing wind direction side was analyzed by using CFD (Computational Fluid Dynamics) simulation. The shape of the buildings and Igune was captured by referring to a digital surface model constructed with aerial images taken using a drone. LES (Large-eddy simulation), which can directly reproduce wind velocity fluctuations composed of turbulent eddies larger than the computational grid. The aerodynamic effects of the Igune were modeled based on the concept of the vegetation canopy model. The weak region behind the Igune extended downward approximately 10 times the height of the Igune. The mean wind speed on the site was reduced by approximately a quarter of the situation without Igune. In addition, it was found that the 99-percentile low-occurrence strong-wind-speed in the courtyard was reduced to a quarter. It was confirmed that the calm wind environment was formed with Igune.

    DOI: 10.14962/jass.38.2_37

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  • POST-DISASTER SURVEY FOR RESIDENTIAL ENVIRONMENT AFTER TYPHOON FAXAI (2019) Reviewed

    Tsubasa OKAZE, Eriko TOMOKIYO, Hideki KIKUMOTO, Yoshihide TOMINAGA, Yingli XUAN, Kunio MIZUTANI, Tadayoshi NAKASHIMA, Kazuyoshi NISHIJIMA

    AIJ Journal of Technology and Design   28 ( 69 )   1083 - 1088   2022.6

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    DOI: 10.3130/aijt.28.1083

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  • Relation between mean and instantaneous values of snow-drift flux under drifting snow Reviewed

    Yuki Ikeda, Risa Kawashima, Satoshi Omiya, Hirofumi Niiya, Kouichi Nishimura, Tsubasa Okaze

    Seppyo   84 ( 3 )   213 - 227   2022.5

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    DOI: 10.5331/seppyo.84.3_213

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  • Statistical analysis of low-occurrence strong wind speeds at the pedestrian level around a simplified building based on the Weibull distribution Reviewed

    Wei Wang, Tsubasa Okaze

    Building and Environment   209   108644 - 108644   2022.2

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    DOI: 10.1016/j.buildenv.2021.108644

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  • Development of a snowdrift model with the lattice Boltzmann method Reviewed

    Seika Tanji, Masaru Inatsu, Tsubasa Okaze

    Progress in Earth and Planetary Science   8 ( 1 )   2021.10

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    Abstract

    We developed a snowdrift model to evaluate the snowdrift height around snow fences, which are often installed along roads in snowy, windy locations. The model consisted of the conventional computational fluid dynamics solver that used the lattice Boltzmann method and a module for calculating the snow particles’ motion and accumulation. The calculation domain was a half channel with a flat free-slip boundary on the top and a non-slip boundary on the bottom, and an inflow with artificially generated turbulence from one side to the outlet side was imposed. In addition to the reference experiment with no fence, experiments were set up with a two-dimensional and a three-dimensional fence normal to the dominant wind direction in the channel center. The estimated wind flow over the two-dimensional fence was characterized by a swirling eddy in the cross section, whereas the wind flow in the three-dimensional fence experiment was horizontally diffluent with a dipole vortex pair on the leeward side of the fence. Almost all the snowdrift formed on the windward side of the two-dimensional and three-dimensional fences, although the snowdrift also formed along the split streaks on the leeward side of the three-dimensional fence. Our results suggested that the fence should be as long as possible to avoid snowdrifts on roads.

    DOI: 10.1186/s40645-021-00449-0

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    Other Link: https://link.springer.com/article/10.1186/s40645-021-00449-0/fulltext.html

  • Large-eddy simulation of flow around an isolated building: A step-by-step analysis of influencing factors on turbulent statistics Reviewed

    Tsubasa Okaze, Hideki Kikumoto, Hiroki Ono, Masashi Imano, Naoki Ikegaya, Takamasa Hasama, Keisuke Nakao, Takeshi Kishida, Yuichi Tabata, Keigo Nakajima, Ryuichiro Yoshie, Yoshihide Tominaga

    Building and Environment   202   108021 - 108021   2021.9

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    DOI: 10.1016/j.buildenv.2021.108021

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  • Comparison of hexahedral, tetrahedral and polyhedral cells for reproducing the wind field around an isolated building by LES Reviewed

    Wei Wang, Yong Cao, Tsubasa Okaze

    Building and Environment   195   107717 - 107717   2021.5

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    DOI: 10.1016/j.buildenv.2021.107717

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  • Elucidations of vertical structures of blowing snow with snowfall Reviewed

    MASUZAWA Satoka, OMIYA Satoshi, OKAZE Tsubasa, NIIYA Hirofumi

    Journal of the Japanese Society of Snow and Ice   83 ( 3 )   259 - 273   2021

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    To elucidate vertical structures of blowing snow with the snowfall, we acquired blowing snow events, which reached equilibrium, from observational data of two months. Estimation of the snowfall frequency in each event was based on snow particle diameters that were greater than 400μm, which were assumed as snowfall particles in this study. Wind profiles were expressed as logarithmic functions of the height; additionally, the roughness length during high snowfall frequency was smaller than during low snowfall frequency at the equivalent friction velocity. The snow-drift flux during low snowfall frequency decreased with increasing height and exhibited uniform distribution at high snowfall frequency. Moreover, the friction velocity dependency of snow-drift flux was confirmed, but the variation was high during high snowfall frequency. The snow-drift flux of during snow particles with less than 200μm diameter decreased with increasing height, whereas that of snowfall particles was vertically uniform. Therefore, the change in the vertical distribution of the snow-drift flux influenced by snowfall frequency was quantitatively explained through the role of snowfall particles to the total snow-drift flux.

    DOI: 10.5331/seppyo.83.3_259

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    Other Link: http://id.ndl.go.jp/bib/031541430

  • Large-eddy simulations of flow field around an isolated building with polyhedral cells: Does boundary layer mesh on building walls always improve numerical accuracy of wind environment? Reviewed

    Wei Wang, Yong Cao, Tsubasa Okaze

    Wind Engineering Research   26   157 - 166   2020.12

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    DOI: 10.14887/windengresearch.26.0_157

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  • Evaluation of wind gust at pedestrian space with a small thermistor anemometer in wind tunnel experiment Reviewed

    Yukimasa Hirano, Hideki Kikumoto, Tsubasa Okaze

    Wind Engineering Research   26   139 - 147   2020.11

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    DOI: 10.14887/windengresearch.26.0_139

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  • Analysis of strong wind caused by the influence of valley topography by using WRF ~Strong wind case occurred in Teshikaga, Hokkaido, Japan~ Reviewed

    Yuki Ikeda, Satoshi Omiya, Hirofumi Niiya, Tsubasa Okaze

    Wind Engineering Research   26   1 - 8   2020.11

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    DOI: 10.14887/windengresearch.26.0_1

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  • Mapping local climate zones for a Japanese large city by an extended workflow of WUDAPT Level 0 method Reviewed

    Xilin Zhou, Tsubasa Okaze, Chao Ren, Meng Cai, Yasuyuki Ishida, Akashi Mochida

    Urban Climate   33   100660 - 100660   2020.9

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    DOI: 10.1016/j.uclim.2020.100660

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  • Evaluation of exceeding wind speed at a pedestrian level around a 1:1:2 isolated block model Reviewed

    N. Ikegaya, T. Kawaminami, T. Okaze, A. Hagishima

    Journal of Wind Engineering and Industrial Aerodynamics   201   104193 - 104193   2020.6

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    DOI: 10.1016/j.jweia.2020.104193

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  • Evaluation of urban heat islands using local climate zones and the influence of sea-land breeze Reviewed

    Tsubasa Okaze

    Sustainable Cities and Society   2020.4

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    DOI: 10.1016/J.SCS.2020.102060

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  • LESによる1:1:2単体建物周辺流れのベンチマークテスト:各種計算条件が計算結果に及ぼす影響 Reviewed

    大風翼, 菊本英紀, 小野浩己, 今野雅, 池谷直樹, 挾間貴雅, 中尾圭佑, 岸田岳士, 田畑侑一, 中島慶悟, 義江龍一郎, 富永禎秀

    日本建築学会技術報告集   26 ( 62 )   179 - 184   2020.2

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    DOI: 10.3130/aijt.26.179

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  • Effect of the numerical viscosity on reproduction of mean and turbulent flow fields in the case of a 1:1:2 single block model Reviewed International journal

    Tsubasa Okaze

    Journal of Wind Engineering and Industrial Aerodynamics   191   279 - 296   2019.8

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    DOI: 10.1016/J.JWEIA.2019.06.013

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  • STUDY ON APPLICABILITY OF WASTEWATER MANAGEMENT BY CONSTRUCTED WETLAND WITH VEGETATION AND ECOLOGICAL LIFESTYLE IN REMOTE ISLAND : CASE STUDY ON OGI ISLAND IN SETOUCHI Reviewed

    Yuki SAKAI, Norihisa KAWASHIMA, Tsubasa OKAZE, Koichi YASUDA

    AIJ Journal of Technology and Design   25 ( 60 )   747 - 752   2019.6

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    DOI: 10.3130/aijt.25.747

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  • EVALUATION OF PEDESTRIAN WIND ENVIRONMENT BASED ON FIELD OBSERVATION WITH SMARTPHONE ANEMOMETER IN OGI ISLAND Reviewed

    Kento MINAMI, Tsubasa OKAZE, Norihisa KAWASHIMA, Koichi YASUDA

    AIJ Journal of Technology and Design   25 ( 60 )   765 - 769   2019.6

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    DOI: 10.3130/aijt.25.765

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  • CFD ANALYSIS CONSIDERING REGIONAL TOPOGRAPHY AND MEASUREMENT OF THERMAL ENVIRONMENT IN GASSHO-STYLE HOUSES IN SHIRAKAWA VILLAGE Reviewed

    Yuki OGAWA, Kiyotaka DEGUCHI, Shun KAWAKUBO, Tsubasa OKAZE

    Journal of Environmental Engineering (Transactions of AIJ)   84 ( 763 )   865 - 872   2019

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    DOI: 10.3130/aije.84.865

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  • DEVELOPMENT OF MICROCLIMATE SIMURATION METHOD COMBINING WRF WITH LES AND FUTURE PREDICTION OF THERMAL ENVIRONMENT IN AN ACTUAL DISTRICT Reviewed

    25   223 - 228   2018.12

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    DOI: 10.14887/kazekosymp.25.0_223

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  • Development of a large-eddy simulation coupled with Lagrangian snow transport model Reviewed

    Tsubasa Okaze, Hirofumi Niiya, Kouichi Nishimura

    Journal of Wind Engineering and Industrial Aerodynamics   183   35 - 43   2018.12

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    DOI: 10.1016/j.jweia.2018.09.027

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  • Influence of urban configuration on the structure of kinetic energy transport and the energy dissipation rate Reviewed

    Yasuyuki Ishida, Tsubasa Okaze, Akashi Mochida

    Journal of Wind Engineering and Industrial Aerodynamics   183   198 - 213   2018.12

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    DOI: 10.1016/j.jweia.2018.10.016

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  • Analysis of climatic factors leading to future summer heatstroke risk changes in Tokyo and Sendai based on dynamical downscaling of pseudo global warming data using WRF Reviewed

    Miguel Yamamoto, Masataka Kasai, Tsubasa Okaze, Kazumasa Hanaoka, Akashi Mochida

    Journal of Wind Engineering and Industrial Aerodynamics   183   187 - 197   2018.12

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    DOI: 10.1016/j.jweia.2018.10.001

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  • GENERATION OF ARTIFICIAL INFLOW TURBULENCE WITH DIGITAL FILTER METHOD FOR LES WITHIN BUILT-UP ENVIRONMENT Reviewed

    25   211 - 216   2018.12

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    DOI: 10.14887/kazekosymp.25.0_211

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  • Wind tunnel experiment and CFD analysis of sand erosion/deposition due to wind around an obstacle Reviewed

    Yoshihide Tominaga, Tsubasa Okaze, Akashi Mochida

    Journal of Wind Engineering and Industrial Aerodynamics   182   262 - 271   2018.11

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    DOI: 10.1016/j.jweia.2018.09.008

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  • Cholesky decomposition–based generation of artificial inflow turbulence including scalar fluctuation Reviewed

    T. Okaze, A. Mochida

    Computers & Fluids   159   23 - 32   2017.12

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    DOI: 10.1016/j.compfluid.2017.09.005

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  • Heatstroke Risk Predictions for Current and Near-Future Summers in Sendai, Japan, Based on Mesoscale WRF Simulations Reviewed

    Masataka Kasai, Tsubasa Okaze, Akashi Mochida, Kazumasa Hanaoka

    Sustainability   9 ( 8 )   2017.8

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    DOI: 10.3390/su9081467

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  • Summer heatstroke risk prediction for Tokyo in the 2030s based on mesoscale simulations by WRF Reviewed

    Masataka Kasai, Tsubasa Okaze, Miguel Yamamoto, Akashi Mochida, Kazumasa Hanaoka

    Journal of Heat Island Institute International   12-2 ( 2 )   61 - 67   2017.7

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  • Large-eddy simulation of non-isothermal flow around a building using artificially generated inflow turbulent fluctuations of wind velocity and air temperature Reviewed

    Tsubasa Okaze, Akashi Mochida

    Journal of Heat Island Institute International   12-2 ( 2 )   29 - 34   2017.7

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  • Evaluation of an extra term Fk in urban canopy model for RANS simulation based using LES data Reviewed

    Shu WATANABE, Hiroaki ATO, Tsubasa OKAZE, Akashi MOCHIDA

    Proceedings of 24th National Symposium on Wind Engineering   73 - 78   2016.12

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  • CFD prediction of effects of windbreak forest on occurrence frequency of blown sand in coastal agricultural area in Sendai plain Reviewed

    渡部朱生, 大風 翼, 高野芳央, 今野 雅, 持田 灯, 小林宏康

    システム農学   32 ( 1 )   11 - 18   2016.1

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    DOI: 10.14962/jass.32.1_11

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  • Influence of various computational conditions in RANS model on the prediction accuracy of concentration distributions: Benchmark tests for providing guidelines of CFD prediction on pollutant/thermal dispersion in urban areas Reviewed

    Tominaga, Y., Okaze, T., Kikumoto, H., Shirasawa, T., Yoshie, R., Mochida, A.

    AIJ Journal of Technology and Design   22 ( 51 )   609 - 614   2016

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    DOI: 10.3130/aijt.22.609

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  • Validation Of prediction method of roof snow depth for an isolated roof building : Prediction of unbalanced snow distribution due to wind on roofs based on CFD Reviewed

    Tominaga, Y., Okaze, T., Mochida, A.

    Journal of Structural and Construction Engineering   81 ( 725 )   1051 - 1059   2016

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    DOI: 10.3130/aijs.81.1051

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  • Development of a new k–ε model to reproduce the aerodynamic effects of snow particles on a flow field Reviewed

    T. Okaze, Y. Takano, A. Mochida, Y. Tominaga

    Journal of Wind Engineering and Industrial Aerodynamics   144   118 - 124   2015.9

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    DOI: 10.1016/j.jweia.2015.04.016

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  • Evaluation of turbulent length scale within urban canopy layer based on LES data Reviewed

    T. Okaze, A. Ono, A. Mochida, Y. Kannuki, S. Watanabe

    Journal of Wind Engineering and Industrial Aerodynamics   144   79 - 83   2015.9

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    DOI: 10.1016/j.jweia.2014.11.016

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  • Generation of Artificial Turbulent Fluctuations of Wind Velocity and Temperature in Unstable Boundary Layer Reviewed

    Tsubasa Okaze, Saori Yumino, Akashi Mochida, Yo Kannuki

    PROCEEDINGS OF NATIONAL SYMPOSIUM ON WIND ENGINEERING   23   55 - 60   2014.12

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    DOI: 10.14887/kazekosymp.23.0_55

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  • THE NEAR FUTURE WEATHER DATA FOR BUILDING ENERGY SIMULATION USING DYNAMICAL DOWNSCALING OF RESULTS FROM GLOBAL CLIMATE MODEL Reviewed

    AIJ Journal of Technology and Design   20 ( 46 )   1041 - 1046   2014

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    DOI: 10.3130/aijt.20.1041

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  • Prediction of the impacts of urbanization using a new assessment system combining an urban expansion model and WRF -Case study for Guangzhou in China Reviewed

    Li, Yuan, Okaze, Tsubasa, Mochida, Akashi

    Journal of Heat Island Institute International   9 ( 2 )   133 - 137   2014

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  • A GENERATION METHOD FOR TURBULENT FLUCTUATION OF WIND VELOCITY AND SCALAR BASED ON CHOLESKY DECOMPOSITION OF TURBULENT FLUXES Reviewed

    Tsubasa OKAZE, Akashi MOCHIDA

    Journal of Environmental Engineering (Transactions of AIJ)   79 ( 703 )   771 - 776   2014

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    DOI: 10.3130/aije.79.771

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  • DEVELOPMENT OF NEW SNOWDRIFT MODEL BASED ON TWO TRANSPORT EQUATIONS OF DRIFTING SNOW DENSITY Reviewed

    Tsubasa OKAZE, Yoshihide TOMINAGA, Akashi MOCHIDA

    Journal of Environmental Engineering (Transactions of AIJ)   78 ( 684 )   149 - 156   2013

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    DOI: 10.3130/aije.78.149

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  • PIV measurements of saltating snow particle velocity in a boundary layer developed in a wind tunnel Reviewed

    Yoshihide Tominaga, Tsubasa Okaze, Akashi Mochida, Yasutomo Sasaki, Masaki Nemoto, Takeshi Sato

    Journal of Visualization   16 ( 2 )   95 - 98   2012.12

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  • DEVELOPMENT OF SUBMODEL EXPRESSING EFFECT OF SNOW PARTICLES ON FLOWFIELD FOR CFD PREDICTION OF DRIFTING SNOW Reviewed

    Tsubasa Okaze, Yoshiteru Takano, Akashi Mochida, Yoshihide Tominaga

    PROCEEDINGS OF NATIONAL SYMPOSIUM ON WIND ENGINEERING   22   67 - 72   2012.12

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    DOI: 10.14887/kazekosymp.22.0.67.0

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  • Wind tunnel investigation of drifting snow development in a boundary layer Reviewed

    Tsubasa Okaze, Akashi Mochida, Yoshihide Tominaga, Masaki Nemoto, Takeshi Sato, Yasutomo Sasaki, Kazusato Ichinohe

    Journal of Wind Engineering and Industrial Aerodynamics   104-106   532 - 539   2012.5

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    DOI: 10.1016/j.jweia.2012.04.002

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  • CFD modeling of snowdrift around a building: An overview of models and evaluation of a new approach Reviewed

    Yoshihide Tominaga, Tsubasa Okaze, Akashi Mochida

    Building and Environment   46 ( 4 )   899 - 910   2011.4

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    DOI: 10.1016/j.buildenv.2010.10.020

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  • Development of a system for predicting snow distribution in built-up environments: Combining a mesoscale meteorological model and a CFD model Reviewed

    Yoshihide Tominaga, Akashi Mochida, Tsubasa Okaze, Takeshi Sato, Masaki Nemoto, Hiroki Motoyoshi, Sento Nakai, Takuya Tsutsumi, Masaya Otsuki, Takahiko Uamatsu, Hiroshi Yoshino

    Journal of Wind Engineering and Industrial Aerodynamics   99 ( 4 )   460 - 468   2011.4

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    DOI: 10.1016/j.jweia.2010.12.004

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  • Analysis of Snowdrift Formation Mechanism by Solving Two Transport Equations of Drifting Snow Densities Reviewed

    Tsubasa Okaze, Akashi Mochida, Yoshihide Tominaga, Yu Ito, Hiroshi Yoshino

    PROCEEDINGS OF NATIONAL SYMPOSIUM ON WIND ENGINEERING   21   101 - 106   2010.12

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    DOI: 10.14887/kazekosymp.21.0.101.0

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  • メソ気象モデルとCFDを接続した都市・建築空間の降積雪シミュレーションシステムの開発 Reviewed

    富永禎秀, 持田灯, 大風翼, 佐藤威, 根本征樹, 本吉弘岐, 中井専人, 堤拓哉, 吉野 博

    日本雪工学会誌   26   235 - 244   2010

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  • CFDを用いた吹雪モデルと雪面熱収支解析に基づく融雪モデルの連成による都市・建築空間の積雪分布予測手法の開発 Reviewed

    伊藤優, 大風翼, 持田灯, 富永禎秀, 吉野博, 佐々木康友

    日本雪工学会誌   26 ( 4 )   245 - 254   2010

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  • BASIC INVESTIGATION OF MODELING FOR EROSION AND ACCUMULATION ON SNOW SURFACE Reviewed

    Yoshihide TOMINAGA, Tsubasa OKAZE, Akashi MOCHIDA, Takayuki SHIDA, Hiroshi YOSHINO

    Journal of Environmental Engineering (Transactions of AIJ)   74 ( 643 )   1083 - 1089   2009

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    DOI: 10.3130/aije.74.1083

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  • 発達過程の吹雪境界層における飛雪流量の空間分布に関する風洞実験 Reviewed

    伊藤優, 大風翼, 持田灯, 富永禎秀, 根本征樹, 吉野博, 佐藤威

    風工学シンポジウム論文集   20   67 - 72   2008

  • 雪粒子の流れ場への影響を組み込んだ新たな飛雪モデルの提案 Reviewed

    大風翼, 持田灯, 富永禎秀, 吉野博, 伊藤優

    風工学シンポジウム論文集   20   73 - 78   2008

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    DOI: 10.14887/kazekosymp.20.0.13.0

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  • 砂面上に置かれた物体周りの侵食・堆積に関する風洞実験及びCFD解析 Reviewed

    富永禎秀, 志田貴之, 持田灯, 吉野博, 大風翼

    風工学シンポジウム論文集   19   109 - 114   2006

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Books

  • 風の事典

    ( Role: Contributor)

    丸善出版  2011 

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MISC

  • Field Observation for Elucidation of Spatiotemporal Structures of Blowing Snow Invited

    Tsubasa OKAZE, Hirofumi NIIYA, Satoshi OMIYA

    Wind Engineers, JAWE   49 ( 1 )   25 - 32   2024

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    Authorship:Lead author, Corresponding author   Language:Japanese   Publisher:Japan Association for Wind Engineering  

    DOI: 10.5359/jawe.49.25

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  • 自然換気・通風の快適性に関する最新研究 Invited

    山本佳嗣, 森上伸也, 大風翼, 丸山裕恒, 吉村奈津江

    空気調和衛生工学   96 ( 5 )   365 - 372   2022.5

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    Language:Japanese  

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  • 市街地環境の予測・分析に果たしてきたRANSの役割と今後の課題 Invited

    大風翼, 富永禎秀, 持田灯

    ながれ   35 ( 3 )   255 - 262   2016.6

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    Language:Japanese   Publishing type:Article, review, commentary, editorial, etc. (scientific journal)  

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  • 実務で活用するCFDの現状とこれから 第2回 都市街区計画へのCFDの適用 Invited

    大風 翼, 井上宗則, 佃 悠

    建築技術   ( 2015年2月 )   62 - 63   2015

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  • 風による雪の輸送がもたらす環境障害 - 市街地内の吹きだまりの予測 - Invited

    大風翼, 富永禎秀, 持田灯

    日本機械学会誌   116 ( 1136 )   16 - 19   2013

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  • Recent Progress in CFD Applications to Snowdrift around Buildings Invited

    TOMINAGA Yoshihide, OKAZE Tsubasa, MOCHIDA Akashi

    Journal of Wind Engineering   37 ( 1 )   42 - 50   2012

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    Language:Japanese   Publisher:Japan Association for Wind Engineering  

    DOI: 10.5359/jawe.37.42

    CiNii Books

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    Other Link: https://jlc.jst.go.jp/DN/JALC/10009195294?from=CiNii

  • 都市レベルの数値解析 Invited

    大風翼, 持田灯

    建築技術   ( 2012年12月 )   2012

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  • 建物周辺の飛雪現象へのCFDの適用 Invited

    富永禎秀, 大風翼, 持田灯

    日本流体力学会誌「ながれ」   28 ( 6 )   477 - 484   2009

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  • Brief Overview on the Panel Discussion "How to Mitigate Snow-ice Disasters in Urban Areas by the Modeling Techniques for Snow Environment"

    TOMINAGA Yoshihide, MOCHIDA Akashi, OKAZE Tsubasa, SHIDA Takayuki

    24 ( 1 )   62 - 63   2008.1

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    Language:Japanese  

    CiNii Books

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Awards

  • 日本風工学会デザイン賞

    2023.5  

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  • 日本雪氷学会平田賞

    2022.10  

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  • 日本ヒートアイランド学会論文賞

    2019.7  

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  • 第25回風工学シンポジウム薫風賞

    2019.3  

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  • 日本風工学会 研究奨励賞

    2015  

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  • システム農学会 北村賞

    2015  

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  • 日本建築学会奨励賞

    2015  

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  • 日本雪工学会 学術奨励賞

    2013  

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    Country:Japan

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  • 風工学シンポジウム論文賞

    2013  

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    Country:Japan

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  • 日本風工学会ベストペーパー賞

    2012  

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    Country:Japan

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  • 雪氷研究大会(2010・仙台) 学生奨励賞

    2010  

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    Country:Japan

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  • 空気調和衛生工学会振興賞・学生賞

    2006  

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    Country:Japan

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Research Projects

  • High-Resolution Snow Hazard Mapping Using Wind and Snow Environment Simulation and 3D City Models

    Grant number:24H00352  2024.4 - 2029.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

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    Grant amount:\47840000 ( Direct Cost: \36800000 、 Indirect Cost:\11040000 )

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  • Study of Snow Accretion and Shedding Processes to Establish Predictive Methods for Reduction of Snow Damage

    Grant number:24H00335  2024.4 - 2028.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

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    Grant amount:\48230000 ( Direct Cost: \37100000 、 Indirect Cost:\11130000 )

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  • 野外観測に基づく吹雪下での雪粒子による消散係数の計測と視程の評価

    Grant number:24K01037  2024.4 - 2028.3

    日本学術振興会  科学研究費助成事業  基盤研究(B)

    大風 翼, 大宮 哲, 松宮 央登, 新屋 啓文

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    Grant amount:\18460000 ( Direct Cost: \14200000 、 Indirect Cost:\4260000 )

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  • 吹雪対策施設(吹き払い柵)の設置環境による吹き払い機能の解明と防雪能力の定量評価

    Grant number:24K07721  2024.4 - 2027.3

    日本学術振興会  科学研究費助成事業  基盤研究(C)

    永田 泰浩, 金田 安弘, 大風 翼, 荒川 逸人

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    Grant amount:\4550000 ( Direct Cost: \3500000 、 Indirect Cost:\1050000 )

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  • 屋敷林の地域への寄与の解明と広域での管理手法の構築:公共財としての維持に向けて

    Grant number:24K08965  2024.4 - 2027.3

    日本学術振興会  科学研究費助成事業  基盤研究(C)

    米澤 千夏, 大風 翼, 豆野 皓太

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    Grant amount:\4550000 ( Direct Cost: \3500000 、 Indirect Cost:\1050000 )

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  • Prediction of ejection and flight trajectory of volcanic ballistic projectiles based on Computer Fluid Dynamics

    Grant number:23K04340  2023.4 - 2026.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

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    Grant amount:\4290000 ( Direct Cost: \3300000 、 Indirect Cost:\990000 )

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  • Challenge on estimation of pleasantness for wind based on brain decoding using machine learning

    Grant number:22K18842  2022.6 - 2024.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Challenging Research (Exploratory)

    Okaze Tsubasa

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    Grant amount:\6370000 ( Direct Cost: \4900000 、 Indirect Cost:\1470000 )

    This study aims to estimate the pleasantness of wind under thermoneutral conditions based on machine learning. The analyzed brain wave was collected through an experiment performed in an artificial climate chamber and an outdoor field measurement. After removing noise from measured brain wave in the chamber experiment, the power spectral density in each brain region were calculated. The power values of the four frequency bands in all regions were used as the features for the classification analysis using machine learning. This study we applied support vector machine (SVM) as the classifier. The mean classification accuracy was 55.2%. Further discussion of applicability of SVM established using the data in the chamber experiment to that in outdoor measurement is expected.

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  • Energy conversion system using wood-derived carbons that contribute to organic waste resource recycling

    Grant number:3RF-2202  2022.4 - 2025.3

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  • 物体後方の渦により発生する音に着目した新たな風速計の開発

    Grant number:2022G-06  2022.4 - 2024.3

    京都大学防災研究所  京都大学防災研究所共同研究  一般

    大風翼, 西嶋一欽, 高野靖

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  • Hazard Map based on Numerical snow Avalanche model and Spatio-temporal variation of snow

    Grant number:21H04601  2021.4 - 2026.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

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    Grant amount:\41860000 ( Direct Cost: \32200000 、 Indirect Cost:\9660000 )

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  • オイラー・ラグラジアンモデルによる飛雪の時空間構造の解明と飛雪・積雪環境の評価

    Grant number:23K20984  2021.4 - 2025.3

    日本学術振興会  科学研究費助成事業  基盤研究(B)

    大風 翼, 大宮 哲, 新屋 啓文

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    Grant amount:\17290000 ( Direct Cost: \13300000 、 Indirect Cost:\3990000 )

    1)LESと個別粒子モデルを連成したオイラー・ラグラジアン飛雪モデルの構築:本研究は、研究計画最終年度前年度応募の課題として、継続して実施した。Large-eddy simulation (LES)と個別粒子モデルを連成したオイラー・ラグラジアン飛雪モデルを構築し、吹雪風洞実験との比較から、モデルの妥当性の検証を行った。続いて、防風林周りの吹雪の空間構造予測のため、防風植栽の数値サブモデルをLESに追加した。
    2)吹雪境界層下での野外観測:北海道弟子屈町内の雪原で野外観測を実施した。2,3年目に実施する吹雪の空間構造を把握のための本観測の予備観測の位置づけで、超音波風速計とスノー・パーティクル・カウンター(SPC)を四方が開けた吹雪境界層中で4高度に設置し、風速及び雪の質量流量の鉛直分布を計測した。高さ1~3 m の雪の流量の最大瞬間値は,高さに寄らず10 分間平均値の15 倍程度となることが明らかとなった他、雪の質量流量と視程の関係について分析を行い、本観測のでの吹雪の空間構造把握のための知見を得た。
    3)模擬フェンス周辺の吹きだまり成長過程詳細観測:上記2)の観測サイトにて、高さ1m開口率0%の模擬フェンスを設置し、1つの吹雪イベントについて、小型LiDARを用いて吹きだまりの成長過程を記録する集中観測を実施した。LiDARで計測した吹きだまりの形状は、UAVを用いた空撮画像より吹雪イベント前後の差分から推定した手法と比較し、数cmの誤差に収まっていることを確認した。さらに、LiDARでノイズのように記録された空間の吹雪粒子について、その除去方法の検討を行い、強風の地吹雪下で雪面形状を取得するための知見を得た。

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  • オイラー・ラグラジアンモデルによる飛雪の時空間構造の解明と飛雪・積雪環境の評価

    Grant number:21H01489  2021.4 - 2025.3

    日本学術振興会  科学研究費助成事業  基盤研究(B)

    大風 翼, 大宮 哲, 新屋 啓文

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    Grant amount:\17290000 ( Direct Cost: \13300000 、 Indirect Cost:\3990000 )

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  • High-resolution analyses on sediment transport of blowing snow and duststorm with large-scale wind tunnel

    Grant number:23K20243  2020.4 - 2025.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

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    Grant amount:\17550000 ( Direct Cost: \13500000 、 Indirect Cost:\4050000 )

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  • High-resolution analyses on sediment transport of blowing snow and duststorm with large-scale wind tunnel

    Grant number:20H01983  2020.4 - 2025.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

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    Grant amount:\17550000 ( Direct Cost: \13500000 、 Indirect Cost:\4050000 )

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  • Evaluation of windbreak forests (Igune) by machine learning for geospatial data and three dimensional analysis of airflow

    Grant number:20K06104  2020.4 - 2023.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

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    Grant amount:\4290000 ( Direct Cost: \3300000 、 Indirect Cost:\990000 )

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  • RTK 搭載バルーンによる⾼密度 3 次元⾵速場実測

    Grant number:2020-G5  2020.4 - 2022.3

    京都大学防災研究所  共同研究  一般

    大風翼, 西嶋一欽, 中嶋唯貴

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  • Challenge of resource circulation within a remote island community through collaboration of agriculture and engineering

    Grant number:19K22006  2019.6 - 2022.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Challenging Research (Exploratory)

    Okaze Tsubasa

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    Grant amount:\6240000 ( Direct Cost: \4800000 、 Indirect Cost:\1440000 )

    In this study, a micro anaerobic digestion system with a 30 L capacity was developed. The system was easily constructed using materials purchased from home improvement stores. In addition, stable fermentation was established using familiar, readily available materials such as seed microorganisms. In the laboratory test, although no mixing in the fermenter was carried out, the methane production efficiency was approximately 60% of the theoretical production value for the COD of the added food waste. In the outdoor experiment on an island in the Seto Inland Sea, by covering the whole fermenter with insulation, the fermentation could be maintained with a 200 W heater even during their winter season.

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  • Development of an energization-regeneration desiccant air conditioning system using a conductive polymer as new moisture absorbing material

    Grant number:19H02294  2019.4 - 2023.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

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    Grant amount:\17160000 ( Direct Cost: \13200000 、 Indirect Cost:\3960000 )

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  • Development of prediction method for drifting snow environments by coupling computational fluid dynamics with Lagrangian particle transport model

    Grant number:18H01592  2018.4 - 2022.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

    Okaze Tsubasa

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    Grant amount:\17290000 ( Direct Cost: \13300000 、 Indirect Cost:\3990000 )

    In this study, we developed a new drifting snow model that can predict unsteady phenomena of drifting by coupling a large-eddy simulation, which can accurately predict turbulent fluctuations, with a Lagrangian particle model that predict the motion of individual particles. To validate the drifting snow model, wind tunnel experiments and field observations in a snowfield were conducted to obtain statistics of wind speed and the mass flux of drifting snow. A meso-meteorological simulation was conducted to discuss observation site, and it was decided in Teshikaga, Hokkaido, where wind direction is stable and strong winds blow during the winter season. Based on comparisons of wind tunnel experiments and field observations, the accuracy of the developed drifting snow model was validated.

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  • Study on Effective Measures for Heat Adaptation in Costal City Based on Prediction of Future Change in Sensible and Latent Heat Balance Caused by Climate Change

    Grant number:17H03349  2017.4 - 2020.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

    Mochida Akashi

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    Grant amount:\16770000 ( Direct Cost: \12900000 、 Indirect Cost:\3870000 )

    In this study, an accurate microclimate simulation method, combining WRF with LES, was developed, and air temperature and humidity increases in the summer of 2050s were simulated. An area with high heatstroke risk was selected based on the risk predicted by a mesoscale model, and the spatial distributions of climatic factors within the selected area were simulated by a microclimate model. This was coupled to a human physiological model to predict the risk distribution in the urban block scale. Also, three dimensional spatial distribution and time variation of sensible and latent heat balance in a coastal city in 2050s was analyzed. The results showed that the effect of sea breeze to decrease the air temperature decreases, and humidity, thus heatstroke risk increases especially in coastal areas. Finally, various urban warming countermeasures were evaluated from multiple perspectives and the priorities of each countermeasure and their changes in the future were presented.

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  • Proposal of guidelines for wind damage mitigation methods controlling shelter performance, visibility, and deposition

    Grant number:16K12858  2016.4 - 2019.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Challenging Exploratory Research

    Tominaga Yoshihide, Mochida AkAshi, Okaze Tsubasa

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    Grant amount:\3380000 ( Direct Cost: \2600000 、 Indirect Cost:\780000 )

    By wind tunnel experiments for mean and turbulent velocity fields around porous windbreak fence, the relationship between the porosity and the flow property were clarified. The influence of the hole shape of the fences was also investigated. The validation database for CFD simulations was provided by the systematic wind tunnel experiment which changed the various parameter such as porosity, opening size, and fence thickness. Next, CFD simulations using porous jump condition were conducted by changing various parameters related to the fence property. By examining the predicted mean and turbulent velocity fields, tentative best practice guidelines of CFD simulation applied to such flow can be provided. Furthermore, some insights of prediction method of sand accumulation and erosion around obstacles using CFD were obtained based on the results of the wind tunnel experiment.

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  • Reconstruction of theory for outdoor thermal environment design based on evaluation and analysis of the health risk in hot summer conditions

    Grant number:26289200  2014.4 - 2017.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

    Mochida Akashi, Okaze Tsubasa, Watanabe Hironori, Junimura Yoshiki

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    Grant amount:\16510000 ( Direct Cost: \12700000 、 Indirect Cost:\3810000 )

    There are two aspects to the countermeasures against urban warming: mitigation and adaptation. Moreover, urban warming is caused by both global warming and urban heat islands (UHIs). This study proposed a system to assess the effects of countermeasures used to mitigate global warming, mitigate UHIs, and adapt to urban warming simultaneously. Moreover, an evaluation method for outdoor health risk in the extremely hot days was developed. In this study, to distinguish between hazards that cannot be controlled by humans and those that can be controlled by modification of urban structures, “natural hazard” and “actual hazard” were defined, respectively.
    Using the assessment systems, the effects of countermeasures were evaluated. Finally, the priority of measures for appropriate design of outdoor urban environment under future climate conditions was concluded.

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  • Artificial generation of inflow turbulence with wind and scalar fluctuations for large-eddy simulation in urban environment

    Grant number:26420578  2014.4 - 2017.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

    Okaze Tsubasa, YOSHIE Ryuichiro, NARITA Kenichi

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    Grant amount:\5070000 ( Direct Cost: \3900000 、 Indirect Cost:\1170000 )

    This study proposed a new method for generating turbulent fluctuations in wind velocity and scalars, such as temperature and contaminant concentration, based on a Cholesky decomposition of the time-averaged turbulent flux tensors of the momentum and the scalar. The artificial turbulent fluctuations generated by this method satisfy not only the prescribed profiles for the turbulent fluxes of the momentum and the scalar but also the prescribed spatial and time correlations.
    Then, the artificially generated turbulent fluctuations of wind velocity and air temperature was applied as inflow boundary conditions for a large-eddy simulation of a non-isothermal flow around a building. The mean wind velocity and mean air temperature predicted from the large-eddy simulation agreed well with the experimental results. The turbulent kinetic energy and the fluctuation of the air temperature also corresponded fairly well with the experiment except for the region immediately behind the inflow boundary.

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  • 暴風雪に伴う建築空間の雪の吹きだまり予測ためのメソ・ミクロ一貫解析手法の開発

    Grant number:25889006  2013.8 - 2015.3

    日本学術振興会  科学研究費助成事業  研究活動スタート支援

    大風 翼

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    Grant amount:\2730000 ( Direct Cost: \2100000 、 Indirect Cost:\630000 )

    ・低温風洞実験に基づく高風速時における吹雪境界層の特徴量の把握を行った。低温風洞の床を雪の飛散しないHard snowから、新雪のようなLoose snowに切り替え、吹雪を発達させ、超音波風速計、Snow Particle Counterを用いて吹雪の特徴量を測定する実験を行った。
    ・飛砂に関する先行研究や南極での野外観測結果などを参考に、雪の削剥に関するサブモデルの定式化を行い、申請者の飛雪現象予測モデルの雪面境界条件として組み込んだ。続いて、今回実施した風洞実験や既往の野外観測を対象に削剥のサブモデルの中に含まれるモデル係数のパラメトリックスタディを行った。パラメトリックスタディの結果を実験・実測の結果と比較し、雪の削剥に関するサブモデルのモデル係数をチューニングし、決定した。
    ・雪の削剥に関するサブモデルを組み込んだ飛雪現象予測モデルを用いて、既往の野外観測を対象に、単体建物周りの雪の空間密度及び積雪分布の予測を行った。建物周辺でのみ削剥が発生するような低風速なケース、広範囲で地吹雪が発生するような高風速のケース、風向や風速が大きく変動するケースなど、さまざまな条件の実験を対象に積雪分布の予測を行ったが、建物側方や建物風上側の吹きだまりや吹き払いの傾向は概ね既往の野外観測を再現できることを確認した。

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  • 都市空間の飛雪現象及び積雪によって変化する対流・放射環境の総合的数値予測法の開発

    Grant number:10J04770  2010 - 2012

    日本学術振興会  科学研究費助成事業  特別研究員奨励費

    大風 翼

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    Grant amount:\2100000 ( Direct Cost: \2100000 )

    1)「積雪環境予測」のための数値モデルの開発
    ・昨年開発した雪粒子が流れ場へ及ぼす影響を表現するサブモデルについては、風速が比較的を大きく、雪粒子がより多く飛散する状況下でも適応できるよう、平成23年度後半に追加で行った風洞実験を基に、モデル係数のチューニングを行った。
    ・雪の飛散・堆積モデルについて、昨年度に開発したサブモデルをさらに改良し、雪面から飛散し雪の積雪全体に対する寄与率を導入することで、降雪時に、風によって形成される建物周辺の吹きだまりの形成要因の分析を可能にした。
    2)吹きだまりを最小にすることを目的とした市街地形態に関するパラメトリックスタディ
    ・上記の1)で完成させた「積雪環境予測」を用いて、市街地形態に関わる建物の密度、隣棟間隔等のパラメータを系統的に変化させた数値解析に基づく積雪環境の数値予測を行い、積雪分布や融雪エネルギーの水平分布を求めた。
    ・建物高さHと隣棟間隔Dの比H/Dが0.71になると、南北の建物間の融雪エネルギーのピーク値は120[W/m2]と,それよりもH/Dが小さい(隣棟間隔が広い)ケースのピーク値(約160[W/m2])に比べて3/4程度まで急減することがわかった。
    3)積雪時の都市・建築空間における対流・放射の相互作用のメカニズムの検討
    ・上記の2)の解析結果の分析を進め、積雪時の都市・建築空間における対流・放射の相互作用のメカニズムを明らかにした。建物南側では、短波放射と下向き長波放射による熱取得量が、顕熱や潜熱の輸送による熱取得に比べ大きいことが分かった。
    ・これを踏まえ、都市・建築空間の積雪環境を形成する都市全体として吹きだまりを最小にする形態を明らかにした。建物高さHと隣棟間隔Dの比で一般化すると、0.50<H/D<0.6[-]のとき、すなわち,建物高さに対して1.75~2倍の隣棟間隔があれば,南北に並ぶ建物の間の領域の積雪量が最も小さくなる可能性の高いという結論を得た。

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