Papers by Author: Yu Kuang Zhao

Abstract: Taiwan is a small island. Some of college campuses are very tiny with large hard pavement to cause un-comfortable outdoor environment. Most of faculty and students like to stay at classroom and use air-conditioner to establish comfort thermal environment. Thus, the outdoor and semi-outdoor thermal equipments are used to detect the parameters of weather. The test and analysis results show that hard pavements cause the un-comfortable outdoor comfort. Mean Radiant Temperatures of grass in summer is higher than the other pavement because that grass pavement is lack of moisture to causes bad outdoor thermal comfort. Therefore, the fine outdoor and semi-outdoor thermal comfort environment should consider the permeable pavement and grass with suitable moisture to cause better outdoor thermal environment and large arbores should be planted widely in campus to establish a better semi-outdoor thermal temperature in campus of the subtropical zone.

Abstract: According to the economic development and the requirement of leisure activities, the popularity of leisure and recreation become very popular in Taiwan. Thus, How to attract tourists to visit these leisure places becomes as a major issue. The questionnaire and outdoor and semi-outdoor comfort detecting devices are applied to analyze these real factors. The results of questionnaire display that “choose a comfortable time to recreation” and “choose the comfort of shade near the local open space” are most important factors for tourists. Then, filed test results show that actual influence factors of tourist activities are outdoor and semi-outdoor thermal comfort, such as wind velocity and surface temperature of construction materials. Thus, the suitable construction material is imitation wood for creating a comfort place.

Abstract: How to maintain a comfortable indoor environment without excessively relying on mechanical HVAC (Heating, Ventilation, and Air Conditioning) is a target to be pursued for future living requirements. The results obtained in this research show that in an office environment, the room temperature monitored during winter is close to the comfortable temperature; however, the office occupants feel that a little warmer indoor temperature is comfort. During summer, the occupants prefer cooler temperature than the comfort temperature. Additionally, Taiwan is located in sub-tropical region with hot and humid summer. Even if the room temperature is maintained in a comfortable range, the occupants still feel not so comfortable because of high humidity. Hence, reducing the room temperature below 23 °C is inferred to make occupants feel comfortable. Questionnaire survey indicates that ventilation is preferred by 30.9% of the respondents for summer and 43.3% for winter as an effective method to improve the stuffy indoor air.

Abstract: The global climate change directly affects the weather pattern of Taiwan. Some research achievements show that buildings will decrease the indoor room temperatures by 1oC during summer and increase the indoor room temperature by 1oC during winter with 6%~10% savings of energy consumption. In this research, the phenolic resin board is used as an experimental roof insulation material in a green roof that is covered with living plants for the objective of reducing summer building air conditioning energy consumption and cost. The influence of roofing materials with various insulation capacities on the building interior temperature is simulated in this study using the basic thermal data measured in the laboratory. Analysis results of computational fluid dynamics, CFD simulation of the temperatures are close to the measured data. Simulation of the insulation capacity of the green roof indicates that the difference between outside and inside temperature is as high as 29°C that demonstrates the insulation capacity of the phenolic resin board. In addition to save energy, the combined insulation technology using phenolic resin board and planted green vegetation coverage on the roof will also contribute to a green and aesthetic environment.

Abstract: The global warming effect causes climate change. Especially, it directly affects the weather pattern of Taiwan. The temperature continually rising leads to higher energy consumption for building air-conditioning. The phenolic resin board is a very good heat insulation and eco-friendly construction material. Otherwise, a green roof covered with living plants for the purpose to reduce heat effect in building are widely used in the world. Therefore, in this research, the phenolic resin board is used as an experimental roof insulation material in a green roof that is covered with living plants for the objective of reducing summer building air conditioning energy consumption and cost. During summer, the difference between inside and outside temperatures across the phenolic resin board exposed to direct sun shine is as high as 8°C±2°C. The combined insulation technology using phenolic resin board and planted green vegetation coverage on the roof will also contribute to a green and aesthetic environment.

Abstract: This study focused on the investigation of the effectiveness of nano-plasma negative air ionization (NPNAI) and photocatalytic oxidation with combining nano-Ag/TiO₂ as photocatalyst and UV light irradiation to enhance the disinfecting capability of full-scale bacterial restraining equipment in the medical nursing institute. Results show the bacteria removal efficiencies (η) of different methodologies, respectively. In this removal method, the contributions of photocatalytic oxidation (PCO) as nano-Ag/TiO₂ (ave. bacterial restraining rate = 73%) were higher than those of NPNAI (ave. bacterial restraining rate = 17%) for the removal of airborne microorganisms. The proposed equipment can disinfect air to restrain bacteria effectively as demonstrated on-site in medical nursing institutions; the results will be valuable references for designing a full-scale commercialized device for large-scale applications in the future.

Abstract: Taiwan is limited in space with dense population, and is located in sub-tropical region with high ambient temperature and humidity. In this research, the phenolic resin is proposed as building materials to use its thermal insulation property for developing a comfortable living and working indoor environment. The phenolic resin is an environmental friendly material, and an excellent thermal barrier. The literature also points out that using phenolic resin plates in buildings will decrease or increase the indoor room temperatures by 1°C during summer and winter, respectively, with 10% savings of energy consumption. In this research, the effectiveness of applying phenolic resin as building materials is evaluated for both winter and summer conditions. The results show that the daytime indoor temperature is 5-8°C lower than outside temperature in summer whereas the indoor temperature can be maintained at 20-22°C in winter..

Abstract: The digital image correlation (DIC) technique is developed for identifying the crack development in brick wall and reinforced concrete beam. This method is tested on brick wall and reinforce concrete beam to evaluate the observation with various strain quantities and mesh sizes. The analysis results reveal that using the von Mises strain field will lead to fine precision of crack observation, and that clearer imagines can be obtained with smaller mesh sizes. This technique is capable of judging crack loading to predict crack occurrences.