Papers by Author: Wen Pei Sung

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: Taiwan is located in the subtropical zone. The climate in summer is hot with high humidity. In order to establish a comfortable office, it needs a lot of active devices, such as: air conditioner to maintain the suitable indoor temperature and humidity. In this study, a business office in the South District Public Health Center, Taichung City is conducted. According to our findings for the office, although the measured indoor temperature was closer to a comfortable temperature during the winter, the occupants of the indoor space still felt excessively warm. By contrast, the occupants of the same space achieved thermal comfort during the summer. This implies that most of the office occupants preferred a cooler environment with a lower temperature. In addition, because the summers in Taiwan are humid and hot, the occupants of an indoor space tend to feel uncomfortable because of the high humidity regardless of whether the temperature is maintained in a comfortable zone. A lower temperature (approximately 21.2-23.9°C) indirectly reduces humidity, thereby making the occupants comfortable.

Abstract: In this study, a low-design-cost and long-endurance unmanned aerial vehicle (UAV) based on the simple microcontroller board and mini-airship technique is proposed. Many well developed positioning sensors, such as GPS, 3-axis Gyroscope, Gravity-sensor and Magnetometer are used. In addition, the control model of Proportional-Integral-Derivative controller is applied to accomplish the long endurance purpose. Such a low-cost design has the potential to accelerate the application of UAV in a variety of video monitoring fields.

Abstract: In this research, two buildings were constructed using phenolic insulation along with considerations of various experimental elements and condition. These environmental factors include natural ventilation, forced ventilation, the mist system, and shading. The results show that when the building is well insulated, the heat transported across the well is effectively prevented indicating that the phenolic resin is effective in insulating the building. Under full sunshine, the room temperature is 10 °C lower than the ambient temperature under full sunshine with the best insulation effect observed at 10:00 am. Shading will provide additional insulation effect to lower the room temperature by 3 °Cmore; the insulation efficiency can also be improved by ventilating the room. Results at 12:00 noon show that shading can effectively reduce solar radiation on the wall whereas force ventilation will carry away heat to reduce the room temperature. Shading will always be effective in reducing the room temperature by about 4 °C, and at 14:00, forced ventilation is the most effective in lowering the room temperature.

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: In recent years, thermal barrier technologies have become an important energy-saving for space heating and cooling of residential and commercial buildings in many countries. Building energy efficiency can be improved by implementing either active or passive energy efficient strategies. Improvements to heating, ventilation and air conditioning systems etc. can be categorized as active strategies, whereas, improvements to building envelope elements can be classified under passive strategies. Using cooling wall system and phenolic resin as thermal barrier are one of the effective passive strategies. Cooling wall system is composed of galvanized iron pipes located inside of walls. Fluid flows inside the pipes and then supply constant cooling temperature. In the study, system using of groundwater as renewable energy source for pipes cooling. The groundwater at depth of more than 5 meters below the surface has constant temperature year round. Lower temperature groundwater would cool the pipes of system by heat exchange process to achieve the cooling effect of wall. The phenolic resin is proposed as construction 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. In this research, cooling wall system and phenolic resin were evaluated to reduce the thermal transfer from sunlight into the buildings, thus reducing the electricity consumption needs for air conditioning of the buildings.

Abstract: This study aims to generate a risk evaluation methodology for the aged dam structure by coupling the micro and macro models created by hydraulic computation and discontinuous deformation analysis (DDA) with numerical manifold method (NMM), respectively. For the macro analysis, DDA+NMM is an energy-convergence algorithm and can be utilized to estimate critical loading based on the potential joints existing within the discontinuous block system. Due to the micro view, the relationship of groundwater level and precipitation can be studied by using hydraulic computation based on the groundwater flow equations. The proposed method presents an evaluation procedure for modeling an aged earth dam with efficient and economic open-source programs. As the result, the simulation can help determining the criterion of risk factors and the prevention strategy.

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: In recent years, 2D digital image correlation method (DIC) has been widely used in the measurement of plane strain. However, out-of-plane displacement could be induced during the loading and it would affect the measurement accuracy. Thus, a 3D measurement is necessary. This study utilizes a simplified 3D DIC to measure the geometry of an object before and after deformation. Then the finite element concept is involved to determine the strain after deformation. A flat plate specimen with in-plane and out-of-plane displacement is observed. Both 2D and 3D DIC are used to analyze the strain. The results show that using 3D DIC to measure strain is feasible and with a very good accuracy.