Effects of high modes on the wind-induced response of super high-rise buildings

For super high-rise buildings, the vibration period of the basic mode is several seconds, and it is very close to the period of the fluctuating wind. The damping of super high-rise buildings is low, so super high-rise buildings are very sensitive to fluctuating wind. The wind load is one of the key loads in the design of super high-rise buildings. It is known that only the basic mode is needed in the wind-response analysis of tall buildings. However, for super high-rise buildings, especially for the acceleration response, because of the frequency amplification of the high modes, the high modes and the mode coupling may need to be considered. Three typical super high-rise projects with the SMPSS in wind tunnel tests and the random vibration theory method were used to analyze the effect of high modes on the wind-induced response. The conclusions can be drawn as follows. First, for the displacement response, the basic mode is dominant, and the high modes can be neglected. Second, for the acceleration response, the high modes and the mode coupling should be considered. Lastly, the strain energy of modes can only give the vibration energy distribution of the high-rise building, and it cannot describe the local wind-induced vibration of high-rise buildings, especially for the top acceleration response.

Effect of Relative Humidity on Catalytic Combustion of Toluene over Copper Based Catalysts with Different Supports

The copper based catalysts,CuO/γ-Al2O3,CuO/γ-Al2O3-cordierite(Cord) and CuO/Cord,were prepared by impregnation method.The catalytic activity of the catalysts was tested in absence and presence of water vapor,and the catalysts were characterized.Temperature program desorption (TPD) experiments of toluene and water on the catalysts were carried out.The influence of water vapor on the activity of the catalysts was discussed.Results showed that addition of the water vapor has a significant negative effect on the catalytic activity of the catalysts.The higher the concentration of the water vapor in feed steam was,the lower the catalytic activity of the copper based catalysts became,which could be mainly ascribed to the competition of water molecules with toluene molecules for adsorption on the catalyst surfaces.TPD experiments showed that the strength of the interaction between water molecules and three catalysts followed the order:CuO/γ-Al2O3>CuO/γ-Al2O3-Cord>CuO/Cord.As a consequence of that,the degree of degradation in the catalytic activity of these three catalysts by the water vapor followed the order:CuO/γ-Al2O3>CuO/γ-Al2O3-Cord>CuO/Cord.However,the negative effect of the water vapor was reversible.

Soundscape of the West Lake Scenic Area with profound cultural background—a case study of Evening Bell Ringing in Jingci Temple,China

From the case study of Evening Bell Ringing at Nanping Hill,one of the West Lake Cultural Landscapes in Hangzhou,China,we investigated the soundscape of a scenic area with a profound cultural background.First,we conducted the soundscape physical index of the area in both winter and spring seasons to analyze its objective graphical expression.Second,we focused on people's reactions to the soundscape in order to obtain a subjective evaluation of each component in the soundscape and integrated environment.Then,the relationship between the objective data and the subjective evaluation was analyzed.Finally,the impacts of the natural environment,history,and cultural factors on the evaluation of the Jingci Temple soundscape were studied.It was found that natural sounds,cultural sounds,and historic sounds were widely acclaimed in people's subjective feelings,which indicated the close relationships among historical and cultural background,soundscape,and natural environment.Thus,the conclusion was made that soundscape should be consistent with the local natural environment and the historical and cultural background.

An individualized interaural time difference model based on spherical harmonic function expansion

A spatially continuous and individualized interaural time difference（ITD） model is proposed based on spherical harmonic expansion,and the spatial sampling theorem of ITD is derived.Analyses on ITDs from 52 human subjects demonstrate that the proposed ITD model, which is represented as a weighted sum of spherical harmonics up to a degree of 6,is adequate for describing the spatial characteristics of ITD including left-right symmetry and front-back asymmetry.The spatially continuous ITD for a specific subject can be accurately reconstructed from 39 measured ITDs at different spatial directions,or approximately evaluated from four head- and pinna-related anthropometric parameters.The proposed ITD model is superior to the existing ITD models in aspects of model structure and accuracy,and is helpful to simplification of ITD measurement as well as anthropometry-based customization of ITD.