간행물

한국기계기술학회지 KCI 등재 Journal of the Korean Society of Mechanical Technology 韓國機械技術學會誌

권호리스트/논문검색
이 간행물 논문 검색

권호

제24권 제6호 (2022년 12월) 51

41.
2022.12 구독 인증기관 무료, 개인회원 유료
In this study, when a communication wire harness is defective due to long-term operation of a vehicle with a high-speed CAN communication network, the unique ID information of each controller and the oscilloscope waveform are analyzed to find defects. As a result of the experiment, it was possible to know whether the circuit of the main wiring was disconnected by the differential voltage analysis, and it was possible to confirm whether the sub-wiring was disconnected due to the generation of saw blade waveforms in the bus idle part. In addition, the fault location could be found with controller ID information and communication circuit analysis.
4,000원
42.
2022.12 구독 인증기관 무료, 개인회원 유료
Numerical analysis has been carried out to predict the thermal characteristics for a LED lens in mold core system. These thermal characteristics inside the lens are largely affected by geometry, material, and initial conditions of the mold core and lens system. Local temperature and heat flux variation inside the lens are compared for several initial temperatures. Maximum temperature inside the lens was decreased rapidly from the beginning of cooling process up to about 10 seconds. There was also large variation of the heat flux at the upper and lower surfaces of the lens with initial temperature distribution. And the heat flux from the thin lower surface of the lens was relatively higher than the opposite-side thick region. In addition, overall heat transfer rate from the lens through the mold core has similar transient distribution from the beginning. These results can be applied as basic heat transfer data for the LED lens design and manufacturing process in the mold core system.
4,000원
43.
2022.12 구독 인증기관 무료, 개인회원 유료
In this paper, the mechanical properties of glass fiber reinforced plastic (GFRP) rebar, which has been applied as an concrete reinforcement, and produced carbon fiber reinforced plastic (CFRP) grid were compared to develop a concrete reinforcement material with excellent mechanical properties. In addition, the mechanical properties of CFRP prepared with each molding process were evaluated. Three molding processes were evaluated: prepreg oven bagging, reaction injection molding (RIM), and pultrusion. The tensile strength of the CFRP grid prepared through pultrusion was 2.85GPa, the elastic modulus was 169.81GPa, and the strain was 1.68%, which was 2.85 times better in tensile strength, and 2.83 times better in elastic modulus compared mechanical properties of GFRP rebar. The strain was confirmed to be equivalent to GFRP rebar.
4,000원
44.
2022.12 구독 인증기관 무료, 개인회원 유료
In this research, the a novel finishing machine was used for hight-precision surface of spherical ball products that have been widely used for on/off valve for hydrogen energy flowing system and in medical field such as artificial hip joint component. The spherical balls products are the workpiece that made by Co-Cr-Mo alloys with 32-mm in diameter and Sa≈ 0.30μm in surface roughness. Their surface roughness was successfully improved via the magnetic abrasive tools that controlled the magnetic field of permanent magnets. The critical input conditions were selected as rotational speed: 800rpm, gap: 3mm, tool grain size: 1-μm finishing time: 0, 3, 6, 9, 12, and 15min. The results of this research showed that under the given finishing conditions, the high surface quality in the terms of surface precision of spherical ball products are successfully achieved, in which the surface roughness is reduced from 0.30-μm to 0.04-μm within the short finishing time at 12min. Therefore, it can be concluded that a novel finishing machine is feasible to be used for improving the surface roughness of spherical ball products, resulted in high surface precision of materials.
4,000원
45.
2022.12 구독 인증기관 무료, 개인회원 유료
In this paper, a numerical study was conducted on the development of HVAC(Heating, Ventilating and Air Conditioning) performance required for a large-scale greenhouse. In order to increase the simulation efficiency, fan model, porous media, and radiator model, etc. provided by Fluent were used based on the part performance analysis such as blowing fans and PTC heaters. Developed simulation method was applied to the decision of fan position to secure the flow uniformity and the determination of the heater specification to maintain the temperature suitable for plant growth. This study is the first step for the development of integrated environmental control system of greenhouse for high-income crop cultivation and the simulation method will be revised after correlation test.
4,000원
46.
2022.12 구독 인증기관 무료, 개인회원 유료
The nonlinear simple pendulum is investigated to find the exact closed-form analytical solution, satisfying initial conditions of angular position and angular velocity. While previous numerous studies have been conducted on the nonlinear simple pendulum, the exact closed-form analytical solution still remains not available in public domain for the most general initial condition including initial angular velocity as well as initial angular displacement. In this paper, the exact closed-form analytical solution for the general initial conditions is derived using Jacobi’s elliptic function and elliptic integral. The result was verified by comparing it with previous studies and the numerical solution of the equation of motion through the Runge-Kutta integration method.
4,000원
47.
2022.12 구독 인증기관 무료, 개인회원 유료
Recently, as interest in safe food and ingredient content has increased, the demand for highly concentrated health functional food that can be manufactured at home is increasing. Accordingly, in this study, we developed a galenic maker that can increase the extraction efficiency of herbal medicine(ginseng) ingredients and shorten the manufacturing time. After verifying the safety of the designed components through structural analysis and thermal flow analysis, the dimensions and shape of the galenic maker were determined. A prototype was produced based on the design process and the performance of the product was verified through extraction efficiency and ingredient analysis.
4,000원
48.
2022.12 구독 인증기관 무료, 개인회원 유료
In order to develop greenhouse cooling and water saving technologies suitable for desert climate, the performance evaluation of the cooling packages and condensate water recovery from cooling fan coil unit. As a result of the application for tomato greenhouse in summer, the root zone temperature of root zone cooling+duct cooling case and root zone cooling case was 25℃ during the day and 20℃ at night, which was suitable for tomato growth. When the nutrient solution tank was cooled, the temperature of the nutrient solution was maintained at 20 degrees, but otherwise, the temperature exceeded 30℃, causing the root zone temperature to rise. Condensate water recovery per fan coil unit was 93L on average per day in August, and was proportional to relative humidity in greenhouse and temperature difference between dew point temperature and the surface temperature of heat exchanger. Tomato growth was found to be improved in the order of root zone cooling+duct cooling, root zone cooling, duct cooling and control. It was analyzed that the yield of root zone cooling+duct cooling, root zone cooling and duct cooling increased by 35%, 28% and 11%, respectively, compared to the control.
4,000원
49.
2022.12 구독 인증기관 무료, 개인회원 유료
This study is to develop a radish skin peeling machine. Currently, radish peeling work is carried out manually, so the unit price is high due to the increase in labor cost, and problems related to hygiene continue to occur. To solve this problem, a field supply type radish skin peeling machine was designed and manufactured. The peeling machine is a principle in which the skin is removed by conveying the radish using a roller and passing through a blade assembly. In this paper, the design and analysis of the roller and blade part applied during the movement of the radish were carried out, and structurally stable results were obtained.
3,000원
50.
2022.12 구독 인증기관 무료, 개인회원 유료
A turbo engine is used to improve engine volumetric efficiency by using the energy of exhaust gas with a device such as a turbocharger. Recently, it has been attracting attention as a solution for responding to environmental issues such as exhaust gas regulation, and its use is being expanded to gasoline and CNG engines as well as diesel engines. However, as electric and hydrogen vehicles enter the automotive market more rapidly, traditional turbo engines also confront many challenges. In this paper, to examine the current status and prospects of the turbo engine, we analyze the related patents in the turbo engine field applied to patent offices in seven major countries, including Korea, USA, China, Japan, Germany, France, and the European Union Patent Office, and analyze the patent application trend. Using ‘the pie’ system of Korea Institute of Science and Technology Information (KISTI), family patents were refined, patent application trends were diagnosed, and the technology and market competitiveness of major applicants were compared and analyzed. Even within the turbo engine market, where traditional automakers and turbocharger manufacturer participate, it was possible to examine the dynamic changes in the market through the analysis of technology and market competitiveness. The main companies leading the technology and market aspects and the companies specialized in the technology and market aspects were observed.
4,000원
51.
2022.12 구독 인증기관 무료, 개인회원 유료
Recently 3d printer industry has two demands. first is color 3d printing. second is mass production using 3d printer that has large bed. According to previous studies, 3D printed objects have different weights depending on filament colors. 3D printed tensile specimens with filaments of various colors were checked to see they had the same weight. If so, we wanted to see it was statistically significant. As a result, we found that the weight of 3D printed objects was statistically significantly different depending on the filament color. The average weight of 3d printed objects is: Black(8.63g), Blue(8.58g), Yellow(8.53g), White(8.48g), Natural(8.46g), Green (8.45g), Red(8.42g).
4,000원
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