Applied Mechanics and Materials Vols. 121-126

Abstract: In this paper, the high temperature tensile tests and ambient temperature tensile tests are performed. The high strength of the welding for 1Cr9Mo/45 and 0Cr18Ni9/45 is somewhat smaller than the ambient strength, but the elongation is improved. Both the high strength and ductility are decreased compared to the results of the room tests. The rupture is located in the side of 1Cr9Mo for the welding of 1Cr9Mo/0Cr18Ni9 at the room temperature, while the rupture is located in the side of 0Cr18Ni9 at high temperature. It is concluded that the strength in high temperature is decreased for 0Cr18Ni9. The rupture happens in the side of 45 for both heterogenic welding joints of 45/0Cr18Ni9 and 45/1Cr9Mo.

Abstract: This research is based on Taiwan’s first zero-carbon green building-Magic School of Green Technology in National Cheng Kung University. Actual energy consumption will be measured to explore benefits of energy-saving. The design origin for this building encompasses 13 green energy-saving techniques. United States Department of Energy dynamic building energy analytical software, eQUEST, is used to execute the strictest energy consumption analytical assessment. It is forecasted to reach an energy-saving efficiency of 65% with energy use intensity (EUI) of 43 kWh/m².yr for the whole building, far below that of 169 kWh/m².yr found in Taiwan low/mid-rise office buildings. This building has begun operation in 2011, through actual readings from Building Energy Management System (BEMS) during January to June, first-half-year accumulated EUI of 19.3 kWh/m².yr against eQUEST analytical assessment of 22.5 kWh/m².yr for the same period. Actual energy consumption analysis for air conditioning, lighting, socket outlet, and power equipment, respectively recorded 41.7%, 11%, 22.3%, and 25% in June. Demonstrating that eQUEST analytical assessed value is very consistent with building’s actual energy consumption readings. The energy consumption standard in the experimental research behind the Magic School of Green Technology stands at world class.

Abstract: This study is a productivity review on the literature gleaned from web of science databases concerning recommendation in E-Learning research. The result indicates that the number of literature productions on this topic is growing in recently 4 years, approximately the same number in 2008, 2009 and 2011. The main research development country is Taiwan, and from the analysis of the distribution of language, English is the most popular language. Moreover the research focuses on are mainly context model and system design to explore fundamental components of E-Learning context and offer a learning environment suitable for users, also the limitations and future research of these research were discussed, so that the direction for future research work can be explored.

Abstract: In 2007, a 2.8-ha multi-function constructed wetland was successfully built in Pingtung County, Taiwan to improve the water quality of local stream and ecosystem of the surrounding environment. The mean inflow rate was approximately 1,350 m3/day. The major influents of the wetland come from the local drainage ditches and streams mainly containing returned water from upstream farmlands and secondary wastewater from hog farms located in the upper catchment of the wetland. Thus, the influents contain moderate to high concentrations of organics and nutrients. The mean measured hydraulic loading rate, hydraulic retention time, water depth, and total volume of wetland system were 0.1 m/day, 5.5 days, 0.7 m, and 7,800 m3, respectively. In this study, water, sediment, and plant samples were collected and analyzed quarterly for each wetland basin during the two-year investigation period. Results show that more than 77% of total coliforms (TC), 78% of biochemical oxygen demand (BOD), 88% of total nitrogen (TN), and 96% of ammonia nitrogen were removed via the constructed wetland system. Thus, the wetland system has a significant effect on water quality improvement and is able to remove most of the pollutants from the local stream through natural attenuation mechanisms. Except for stream water quality improvement and rehabilitating the natural ecosystem, this wetland also offers more water assessable eco-ponds and eco-gardens for public. This constructed wetland has become one of the most successful multi-function constructed wetlands in Taiwan.

Abstract: For seeking out suitable means of thermal insulation system of building envelope in south China, this paper has conducted simulation analysis on respective energy consumption of the typical residential template in cold region and south China, when adopt exterior thermal insulation system or interior thermal insulation system. The study has shown that the exterior thermal insulation system is much better than the interior thermal insulation system in energy efficiency in the cold region, but there isn’t obvious difference between them in south China. And from the aspects of the climate’s influence on the insulation quality, the installation’s influence on the building facades and the construction practices, it is proved that the interior thermal insulation system is more suitable than the exterior thermal insulation system in south China.

Abstract: A micro air journal bearing for micro gas turbine engine is designed in this paper. 2D simulation of the aerodynamic micro air bearing is conducted to investigate the effect of the main parameters of the air bearing on the load capacity, including the clearance between the air bearing and shaft, the gear number and height of the air journal bearing, the rotational speed of rotor. The optimum value of the important parameters are explored and presented. The time correlation method is used to solve the RANS (Reynolds Averaged Navier-Stokes) equations. Requirements both from load capacity and motion stability is considered and compromised for a better and stable performance of the air journal bearing. The shaft is stably rotated in a relatively low speed of 1.18×105rpm, which is much lower than other researches and can be achieved easily.

Abstract: Starting system plays an important role in a hydraulic free piston engine (HFPE) and hydraulic accumulator/directional control valve combination is often employed. In this paper, the starting process of a typical starting system composed of a hydraulic bladder accumulator is firstly described, and then the mathematical model of the starting system is established and analyzed as well as some special situations are discussed.

Abstract: According to medical and physiology study of human health, combined with the authoritative media chronicle , it can be sure that the crawl is a very comprehensive range of whole body movement.This design is based on ergo- new crawl exercise machine. it uses software such as Matlab and ansys ug into Structure design and load analysis , the check and Practical application,it is proved to satisfy a 150 kilograms user’s need. it provides the user with a variety of modes, such as the exercise forwardly or exercise passively. At the same time, it is equipped with the safety precautions and voice control and other perfect facilities.The crawl exercise machine can be used extensively in the family, the hospital, the fitness club, etc.

Abstract: Bipropellant-powered hydraulic free piston engine (BHFPE), as a new type of HFPE, takes advantage of bipropellant in place of conventional fossil fuel, and adopts a catalytic ignition instead of the conventional spark or compression ignition. In this paper, the operational principle and working process of a BHFPE are described firstly, then the chemical formula and molar mass as well as the heating value of the bipropellant i.e. kerosene/HTP combination are dealt with respectively. Thereafter analysis on the internal energy-flow i.e. energy input, transfer, dissipation and output, during a working cycle of the BHFPE are analyzed. Additionally the operating parameters such as working efficiency, maximum speed of the free piston assembly (FPA) and the output hydraulic energy are derived.

Abstract: For the seam feature measurement of the tight butt joint without misalignment in laser welding, current vision sensor cannot obtain the seam gap width and seam position stably and reliably. In this paper, a seam measurement method based on the micro depth of field is proposed. A four times optical magnification lens, a CCD/CMOS camera and an external LED lighting unit are used to constitute the measure system, which can be used for the tight butt joint for laser welding. Experiment indicated that it can obtain the seam gap width and seam position stably and correctly. With the method, seam surface normal vector also can be measured. The measurement accuracy for the seam gap width and seam position is 5 µm and 6 µm, respectively. Furthermore, the narrowest welding seam gap that can be measured by this method is 0.02 mm, which is fully satisfied the demand of the seam measurement in laser welding.