간행물
한국기계기술학회지 KCI 등재 Journal of the Korean Society of Mechanical Technology 韓國機械技術學會誌
- 발행기관 한국기계기술학회
- 자료유형 학술지
- 간기 격월간
- ISSN 1229-604X (Print)2092-0385 (Online)
- 수록기간 1999 ~ 2024
- 주제분류 공학 > 기계공학 공학 분류의 다른 간행물
- 십진분류KDC 550DDC 620
권호리스트/논문검색
제24권 제4호 (2022년 8월) 36건
21.
2022.08
구독 인증기관 무료, 개인회원 유료
In order to analyze the pressure drop of the fluid passing through the hydraulic coupler, a flow model using the Computational Fluid Dynamics (CFD) analysis technique was developed and the fluid flow rate and pressure distribution inside the coupler were analyzed. The analysis model was corrected by comparing the pressure drop measurement using a 6.35mm hydraulic coupler with the ISO reference value and the simulation prediction value. Using the calibrated model, the flow rate and pressure drop of 13 types of hydraulic couplers distributed on the market were analyzed, and their performance was determined by comparing them with ISO reference values. In the case of type A coupler, the pressure drop was generally higher than the ISO reference value, and in the case of type B coupler, the pressure drop was similar to or lower than the ISO reference value. It was confirmed that the complex flow analysis inside the hydraulic coupler could be easily performed through computational fluid dynamics (CFD) modeling, and based on this, problems could be identified and performance could be improved performance.
4,000원
22.
2022.08
구독 인증기관 무료, 개인회원 유료
Due to environmental pollution, regulations on fossil fuels are required. There is a movement for the regulations by using LNG fueled propulsion ships. LNG is an eco-friendly fuel that does not emit NOx or SOx during combustion, but its boiling point is -163°C. Under that condition, the use of metal is restricted, and IMO defined applicable materials through IGC code. Among the metals, 9% nickel steel is one of excellent mechanical properties such as yield strength and tensile strength in cryogenic condition. Thus 9% nickel steel is widely used in cryogenic storage containers for ships. In addition, laser welding, which minimizes thermoelastic distortion by applying a concentrated heat source to a narrow area for a short period of time, is in the spotlight. So, this study is a basic research to predict and respond to thermal distortion during laser welding. Secondary version of the representative heat source model was derived through the author's previous research with STS304L, and the heat source model was derived by applying the heat source model to 9% nickel steel in this study. 9% nickel steel is a material that is in high demand and is widely used in the manufacture of cryogenic containers, so this study is expected to be able to respond immediately to the field.
4,000원
23.
2022.08
구독 인증기관 무료, 개인회원 유료
Phosphate coating is applied to the surface of the round bar material used in the multi-stage cold forging process for the purpose of lubrication. The film characteristics are determined according to the conditions of the phosphate film treatment process. In this study, the film properties according to the phosphate treatment conditions were defined as the coefficient of repeated friction and quantitative analysis was performed. Different friction behaviors were exhibited depending on the film properties, suggesting that optimization of the phosphate film treatment conditions is possible based on this. Finally, as a practical example, friction behavior according to the film characteristics was applied to the automotive engine bolt forming process. As a final conclusion, the need for linkage analysis with phosphating conditions for optimizing the forging process was raised. In addition, it can be seen that damage to the phosphate film should be considered in the process of predicting the limiting life of the die.
4,000원
24.
2022.08
구독 인증기관 무료, 개인회원 유료
In this study, the cooling performance change according to the arrangement of the fin-tube heat exchanger using a single tube and the cooling performance change according to the air flow rate were studied. The arrangement of basic heat exchanger was set to 4 columns and 4 rows, and the performance change was studied while changing the columns and rows. In addition, the performance change was investigated by changing the air flow rate of the basic heat exchanger.
4,500원
25.
2022.08
구독 인증기관 무료, 개인회원 유료
Diesel engine has the advantages of strong power, low fuel consumption and good durability, so it has been widely used in transportation, automobile, ship and other fields. However, the nitrogen oxides(NOx) and particulate matter(PM) emitted by diesel engines have become one of the main causes of air pollution. Especially during idling, the engine temperature is low, and there are more residual exhaust gases in the combustion chamber, resulting in the formation of more harmful emissions. In this study, performance of a single cylinder, four-stroke, direct injection (DI) diesel engine fueled with diesel–biodiesel mixtures has been experimentally investigated. The findings show that a remarkable improvement in PM–NOx trade-off can be achieved by burning diesel-bioethanol blend fuels.
4,000원
26.
2022.08
구독 인증기관 무료, 개인회원 유료
The role of QR Code robots in smart logistics is great. Cognitive robots, such as logistics robots, were mostly used to adjust routes and search for peripheral sensors, cameras, and recognition signs attached to walls. However, recently, the ease of making QR Codes and the convenience of producing and attaching a lot of information within QR Codes have been raised, and many of these reasons have made QR Codes recognizable as visions and others. In addition, there have been cases in developed countries and Korea that control several of these robots at the same time and operate logistics factories smartly. This representative case is the KIVA robot in Amazon. KIVA robots are only operated inside Amazon, but information about them is not exposed to the outside world, so a variety of similar robots are developed and operated in several places around the world. They are applied in various fields such as education, medical, silver, military, parking, construction, marine, and agriculture, creating a variety of application robots. In this work, we are developing a robot that can recognize its current position, move and control in the directed direction through two-dimensional QR Codes with the same horizontal and vertical sides, and the error is to create a QR Code robot with accuracy to reach within 3mm. This paper focuses on indoor mobile robot position recognition and driving experiment using QR Code during the development of QR Code-aware indoor mobility robots.
4,000원
27.
2022.08
구독 인증기관 무료, 개인회원 유료
Failure to comply with the performance test requirements for the centrifugal pumps at power plants often results in performance dissatisfaction as a result of field tests. This study proposed a method of reducing the uncertainty of the field test results by evaluating the systematic error in the measurement system caused by failure to follow the test requirements using the computational fluid dynamics(CFD) technique. As a result of the evaluation of the systematic error and reflecting it in the performance test data, it was confirmed that the error occurred at a constant rate with respect to the flowrate and that the pump, which showed a difference in performance actually had the same performance.
4,000원
28.
2022.08
구독 인증기관 무료, 개인회원 유료
This study compared and analyzed the difference in performance between the existing soot probe and the improved one that was applied to the actual inspection vehicle at the actual inspection site, which has been developed under the specific conditions based on the excellent results through the performance evaluation. As the results, probe(b) involves a structure designed close to the center of the circumference of the exhaust pipe, and the suction efficiency was improved by adding a center unit. The improved probe(b) can enhance the effectiveness of the inspection when applied to total and regular tests inspections, and the possibility of contributing to the reduction of carbon dioxide emissions generated in the transportation sector has been confirmed.
4,000원
29.
2022.08
구독 인증기관 무료, 개인회원 유료
In this study, corrosion fatigue crack propagation was investigated in pH buffer environment using the giga strength steel and its heat-affected zone, and the results were compared with theoretical model prediction. Also, the pure corrosion effect on fatigue crack propagation in a corrosive environment was compared with the modified Forman equation. As results, the average value of corrosion rate obtained as the ratio of the net corrosion-induced crack length to the total crack length under cyclic loading in the base metal and heat-affected zone under experimental loading conditions. These results exhibit a new theoretical method for corrosion fatigue crack propagation that predicts a purely corrosion effect on the behavior to be determined.
4,000원
30.
2022.08
구독 인증기관 무료, 개인회원 유료
In this study is a study to measure the section by voltage through the high integration of the circuit of the inspection equipment for the power supply circuit of semiconductor equipment. The experiment was conducted by increasing the -1.5∼4 voltage section by 0.5V. At this time, the tolerance was applied to ±0.1%+5mA. Although the voltage increased through the experiment, the accuracy of the measurement data did not change, and it was confirmed through this experiment that the null hypothesis(H0) was adopted in each section through the hypothesis test.
4,000원
31.
2022.08
구독 인증기관 무료, 개인회원 유료
Various optical devices are utilized to fire artillery in Korean Army. To transport and store the optical devices, some cases are made up for a set. The covers of cases are made of Glass Fiber Reinforced Plastic(GFRP) and resin. Because of materials of case, it has a disadvantage in productivity for manufacturing covers and assembling components. In this study, ABS resin is presented for alternative and verify possibility through FEM analysis. Comparing with GFRP, max stress-ratio of ABS is decreased 19.6% for bottom, 8.2% for side and 25.4% for edge. Also each strain is changed 17.3%, 180.3% and 17.7%. According to the research results, ABS resin is considered possible for alternative. And the number of components is decreased for around 73.8%.
4,000원
32.
2022.08
구독 인증기관 무료, 개인회원 유료
A Study on the Development of Hydrofluoric Acid Control Valve Module for Semiconductor Wafer Process
In this study, we intend to develop a control valve with oxidation resistance for hydrogen fluoride that can be applied to the semiconductor production process. Operated Valves currently in use is a form of assembling an air cylinder to the valve body. These valves generally have a cylinder body made of aluminum (Al), so they may corrode depending on the external environment, and the solution leaks along the rod inside the cylinder, causing damage to parts due to corrosion. To solve this problem, the valve plug shape was developed by devising and applying a plug using a valve different from the existing method, and it is possible to block the inflow of hydrogen fluoride into the valve control unit, thereby preventing damage to parts as well as maintaining stable valve operation.
4,000원
33.
2022.08
구독 인증기관 무료, 개인회원 유료
In this study, 3D design, vibration analysis and experiment, and feed rate performance test were performed to develop a vibratory bowl feeder for supplying ultra-thin plate parts of less than 50 microns. The natural frequency and resonant frequency of the vibratory bowl feeder were obtained through the vibration analysis and experiment, and it was confirmed that the results of the analysis and experiment agree well. Through the feed rate experiment, it was confirmed that up to 610 ultra-thin parts per minute were fed at 250Hz and a supply voltage of 220V, where the excitation frequency and the resonant frequency match. And through analysis and experimental research, it was confirmed that the development of a vibratory bowl feeder for supplying ultra-thin parts was successful.
4,000원
34.
2022.08
구독 인증기관 무료, 개인회원 유료
This paper proposes a solution to the out-of band oscillation signal and in-band low transmitter power output that occurrs during the low-temperature operation test for the new mine detector GPR signal transmission and reception module. Tests were performed by applying the optimal values of capacitors and inductors through circuit analysis simulation under the limited space, as a result, it was confirmed that the gain and return loss were improved at all-band thereby preventing oscillation signal and low transmitter power output.
4,000원
35.
2022.08
구독 인증기관 무료, 개인회원 유료
In order to manufacture a mask to prepare for infectious diseases such as COVID-19 and yellow dust, it is manufactured through the process of input, fusion, cutting, band attachment, defect inspection, and packaging. Domestic mask producers introduced Chinese facilities to keep up with explosive demand due to the rapid spread of COVID-19 in 2020, but serious problems arise in durability. Therefore, domestic processing and tooling companies have developed and supplied molds, but since supply is not smooth compared to demand, research on the development of mask molds with durability reliability is urgently needed to supply masks stably. This technology development aims to supply a mask with excellent quality to a market by applying dots capable of welding and re-painting to a mold for cutting applied to a mask manufacturing process and developing dots optimized for paper angles.
4,000원
36.
2022.08
구독 인증기관 무료, 개인회원 유료
In this study, using the developed pilot device, an experiment was conducted with groundwater according to the calcium carbonate concentration and silica concentration for a certain period of time to determine the degree of RO membrane contamination according to water quality. In addition, using wastewater with severe fouling of raw water, the treatment efficiency is compared through an experiment with a pilot device, the operation progress is evaluated for the scale effect, and the stability and convenience of the developed product are considered.
4,000원
1
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