Hong Jin

Effects of individual sound sources on the subjective loudness and acoustic comfort in underground shopping streets

Previous studies have demonstrated that human evaluation of subjective loudness and acoustic comfort depends on a series of factors in a particular situation rather than only on sound pressure levels. In the present study, a large-scale subjective survey has been undertaken on underground shopping streets in Harbin, China, to determine how individual sound sources influence subjective loudness and acoustic comfort evaluation. Based on the analysis of case study results, it has been shown that all individual sound sources can increase subjective loudness to a certain degree. However, their levels of influence on acoustic comfort are different. Background music and the public address system can increase acoustic comfort, with a mean difference of 0.18 to 0.32 and 0.21 to 0.27, respectively, where a five-point bipolar category scale is used. Music from shops and vendor shouts can decrease acoustic comfort, with a mean difference of -0.11 to -0.38 and -0.39 to -0.62, respectively. The feasibility of improving acoustic comfort by changing certain sound sources is thus demonstrated.

Architectural Factors Influenced on Physical Environment in Atrium

In the atrium of public buildings, the physical environment is determined by architectural features in various ways; therefore, an integrated consideration of the overall physical environment is important. The aim of this chapter is to find out the common factors, which influence the daylighting, acoustics, natural ventilation, and thermal environment from the viewpoint of architectural design. Based on a systematic examination and analysis of previous studies in various aspects of physical environment, different effects of material properties, atrium geometry, atrium shape, roof structure, and adjoining spaces on the daylighting, acoustics, natural ventilation, and thermal environment have been revealed. Consequently, common factors which have influenced on two or more aspects of physical environment have been identified, along with their tendency of influence. It is expected that the results would help to optimize, at the early design stage, the physical environment.

Subjective Evaluation of Acoustic Environment in Underground Spaces

Previous studies have demonstrated that users’ evaluation of acoustic environment such as subjective loudness or acoustic comfort depends on a series of factors in a particular space, rather than only on sound pressure levels. In this study, more than 2800 interviews have been undertaken at underground spaces in Harbin, China, to find out influencing factors to users’ evaluation, considering both space conditions and demographical factors. Based on the analysis of case study results, it has been found that in underground spaces, background music is generally noticeable and preferred, and it is useful for psychologically ‘masking’ other less preferred sound sources. While there is a linear correlation between the measured LAeq and the subjective loudness, the relationship between the measured LAeq and the acoustic comfort evaluation is of a parabolic shape, and the acoustic comfort is the best when LAeq is around 65-70dB. There is no significant difference between different age groups, whereas people with a higher income level tend to feel that an underground space is nosier and less acoustically comfortable.

Approach on the Survey Method for Sound Environment in Underground Spaces

In high density cities underground spaces are rather common. In this study the sound environment survey method in underground spaces has been explored, aiming at finding out the relationships among the environment, space, people and sounds in such spaces, as well as their similarities and differences with urban open spaces. Based on the concept of Likert scaling, questionnaires and interview methods have been designed. Using the methods, soundscape surveys have been carried out in ten underground shopping streets in Harbin, China, considering both staff and customers. By analysing the results, the reliability and validity of the method are examined.

Window ventilators in severe cold areas: Design and simulation

With the changing requirements for thermal comfort and ventilation in severe cold areas of China, the design of window ventilators becomes more important. In this paper, a series of field studies have been carried out, analysing the reason of condensation phenomenon and the characters of severe cold areas. On the basis of researches, the whole model of window ventilators has been designed. At last, to validate the effects of window ventilators, some computer simulations have been verified.

Noise control in underground shopping centre

Underground shopping centres are important public underground spaces with large user flow volume, so technical measures of noise control for such spaces not only affect physical and mental health of users but also touch on whether the articulation of public address system can satisfy the requirements for safe evacuation under emergency, which are paid more and more attention to. According to the noise analysis, rational proposals for noise control are put forward for underground shopping centres in the paper and feasible technical measures are also explored to promote safe and sound development, thus beneficial discussion and attempt are carried out for disaster prevention and disaster reduction in urban underground public spaces.

Low-carbon rural house design practice in north country of China

Rural houses of north China were built in severe environment with rather lower economic and technological support. Thermal properties and indoor comfort level are needy to be increased. With the premise of fulfilling basic building requirements of function, structure, the design of this demonstrated straw house in Daqing explored local green material and renewable sources and combined with low-tech passive design strategies. Further study subjects and field measurement data will be provided by this project. It is also the show case of proper sustainable building technologies in this region.

Evaluation of the protection of historical buildings

In order to promote sustainable development of the existing historical building in cities, take Daowai historical site in Harbin as an example, the multiple value properties and characters of existing historical building are analysed and synthetical estimate index system for historical building is presented in this article. This system consists of value of history conservation, cultural art, building technology and economic. Classification standards of estimate indexes of historical building are discussed according to multiple value properties and characters of existing historical building. And basing on Analytic Hierarchy Process (AHP) of the evaluation, the weight of each factor is determined. Moreover, fuzzy comprehensive evaluation model is used to evaluate synthetical value of existing historical buildings in Daowai. The existing historic buildings in Daowai are divided into three classes. Scientific basis for renovation of historical sites in the cities is provided as well.

Energy efficiency research of straw brick wall in rural house in cold areas of China

In cold areas, the amount of heating energy is closely related to the envelop enclosure of house. Among the envelop enclosure, the wall is the main way of heat loss, accounting to about 50% of the total. Based on the investigation of the straw brick houses in cold rural areas, this paper compared the energy consumption of straw brick wall with that of the traditional clan brick wall and EPS complex wall oriented to all life cycle. Meanwhile, with the energy simulation software—Dest simulating the heating energy consumption in the using stage of houses, the result was that straw brick house can save over 50% energy compared to the traditional clan brick house. So it can be concluded that the straw brick wall is not only suited to the environmental protection, but also energy efficient and economical, adapt to be spread in cold rural areas in China.

Sustainable development strategy of earth building

Earth construction is a kind of natural construction system which has good thermotechnical property. Within its life cycle, its energy consumption is much lower than conventional construction. Therefore, it is suitable for our low-density and small model building groups in rural areas. However, traditional earth construction has many problems. Our thesis analyzed the data about the survey in rural areas in Heilongjiang. In this thesis, we focus on analyzing damage of earth construction, influence of natural force and anti-disaster strategy of earth construction in material, structure and energy conservation. Under the new area background of low-carbon, this thesis intends to make earth construction meet the need of construction of new socialist countryside to get good inheritance and development.