Building Services System Laboratory

H. Okuyama

Hiroyasu Okuyama

Office: 8-56 Ext.: 3432


12/1987, D.Eng., Waseda University

A. Yoshiura

Atsumasa Yoshiura
(Assistant Professor)

Laboratory: 8-57 Ext.: 3442


07/2014, D.Eng., Yamaguchi University

Research Field

Building Services, Building Environmental Engineering, Building Physics.

Research Subjects

  • 1.Methods for predictive calculation of temperature, humidity, gas concentration, and thermal load variations by thermal and ventilation network models.
  • 2.System parameter identification methods for such models from field measurements.
  • 3.Methods for optimal system design and control.


Building services designed to make indoor environments comfortable must also be designed to allow sustainable coexistence with the global environment. Moreover, healthy indoor environments require control of the thermal environment and appropriate ventilation and humidity. Our goal is to create buildings and equipment that are sustainable, healthy, and energy efficient. We also investigate various architechtural methods for environmental symbiosis and green energy systems.
We study and develop practical computer simulations and engineering models for predictive calculation and optimization of indoor thermal and air quality environments and annual energy consumption by air conditioning. We also study system identification methods that use the least squares method to estimate various parameters for these models from measured changes in temperature and gas concentration. These methods allow the performance of buildings to be evaluated. For calculating building heat transfer, factors such as heat loss coefficients, solar heat gain coefficients, and effective heat capacity can be estimated, as can air flow and ventilation between multiple rooms for ventilation. This allows standardized measurement methods to be developed for academia and organizations, such as Japanese Industrial Standards and The International Organization for Standardization, including improvements in statistical methods for analyzing uncertainty and reliability.
Taking similar models as a basis, we can determine evaluation functions from the sum of thermal neutrality, low-energy and low-exergy features, investigate theories to optimize levels of various controls and operations with the Lagrange multiplier method. These methods can optimize systems to use low-quality energy sources, such as solar and geothermal heat, effectively.

  • 1) H. Okuyama, Y. Onishi, “System parameter identification theory and uncertainty analysis methods for multi-zone building heat transfer and infiltration,” Building and Environment, vol. 54, pp. 39–52 (2012).
  • 2) H. Okuyama, Y. Onishi, “Uncertainty analysis and optimum concentration decay term for air exchange rate measurements: Estimation methods for effective volume and infiltration rate,” Building and Environment, vol. 49, pp. 182–192 (2012).
  • 3) H. Okuyama, Y. Onishi, “Reconsideration of parameter estimation and reliability evaluation methods for building airtightness measurement using fan pressurization,” Building and Environment, vol. 47, pp. 373–384 (2012).
  • 4) H. Okuyama, Y. Onishi, S. Tanabe, S. Kashihara, “Statistical data analysis method for multi-zonal airflow measurement using multiple kinds of perfluorocarbon tracer gas,” Building and Environment, vol. 44(3), pp. 546–557 (2009).
  • 5) H. Okuyama, “Optimization theory for state and energy supply based on a heat and moisture transfer network model and numerical investigation,” Proceedings of the 7th International Conference on Indoor Air Quality and Climate, Nagoya, Japan, July 21-26, vol. 2, pp. 485–490 (1996).

Architectural Institute of Japan (AIJ), The Society of Heating, Air-Conditioning, and Sanitary Engineers of Japan (SHASEJ), American Society of Heating, Refrigerating and Air-conditioning Engineers (ASHRAE), International Solar Energy Society (ISES).

Current members
◯ Professors: 1 ◯ Assistant Professors: 1
◯ Undergraduates: 12

Alumni: Undergraduates: 38