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
제25권 제1호 (2023년 2월) 20건
1.
2023.02
구독 인증기관 무료, 개인회원 유료
This paper proposes a method to evaluate the structural safety of a large wide-width greenhouse structure against wind load caused by a typhoon through a fluid structure interaction analysis technique. The conventional method consisted of roughly estimating the wind load based on the relevant laws and regulations, and determining safety through structural analysis. However, since the wind load changes nonlinearly according to the wind speed distribution and wind direction around the greenhouse and the external shape of the structure, there are many uncertainties in the existing structural safety evaluation method, and it is difficult to accurately determine the design margin. In this study, a systematic method was developed to accurately calculate the wind load acting on a greenhouse structure and evaluate structural safety by considering the characteristics of wind through a fluid structure interaction analysis using coupled computational fluid dynamics and computational structural mechanics. Using the proposed method, it is possible to significantly reduce the manufacturing cost because it is possible to obtain an optimal design that reduces the over-conservative design margin while securing the structural strength of the greenhouse.
4,000원
2.
2023.02
구독 인증기관 무료, 개인회원 유료
As the time and cost of body repair can be greatly incurred due to differences in individual technologies, body repair technology should be discussed based on data on general working standards and costs, and as new material technology is applied to the body, continuous learning and experiment on vehicle body repair technology is essential. Since the left and right apron and side members with SPR bonding technology are made of different materials, aluminum and high-strength steel, the restoration of the left and right apron side members should be considered technically, as well as safety and environmental pollution. In this study, we experiment with heterogeneous apron and side members applied with SPR bonding and analyze the results.
4,000원
3.
2023.02
구독 인증기관 무료, 개인회원 유료
Stainless steel is used in many industrial fields due to its excellent properties such as workability, strength, ductility, and corrosion resistance, and various properties required in the manufacturing field depending on the constituent components. pump impellers used in seawater and underwater require high corrosion resistance and high rigidity to prevent corrosion and damage, so they are a representative part group to which Stainless materials are applied. Through the introduction of the CMT(Cold Metal Transfer) process, a manufacturing method through WAAM(Wire Arc Additive Manufacturing) technology, which has advantages of lower production cost and excellent fatigue strength compared to the existing casting method, is being proposed. Recently, prior research on the WAAM process has been conducted on various materials, but most of the research results published so far are focused on the DED(Direct Energy Deposition) process, and a good WAAM shape design study using austenitic stainless steel is lacking. in this study, using the CMT process, the relationship between the change in bead shape and process parameters was confirmed in the BoP(Bead on Plate) welding experiment using wire made of austenitic stainless steel STS-308.
4,000원
4.
2023.02
구독 인증기관 무료, 개인회원 유료
In order to apply to high-nickel cathodes for high-capacity and stability enhancement of lithium-ion batteries, the characteristics of the coating film were reviewed using the conventional nickel plating method. The surface morphology of the plating layer and the measurement of the surface roughness were analyzed according to scan size and rate using the contact mode of Atomic Force Microscopy. The hydrogen ion concentration (pH) of the electrolyte played an important role in shaping the metal ion plating. As the overpotential of the surface increased during plating, the crystals grew in a direction other than the main crystal growth direction. The increase in on-time during pulse plating appears to result in coarse particles as much of the applied current is consumed by the reduction of hydrogen ions, resulting in lower current efficiency. From the AFM image, it was confirmed that the blackening of the plated film was due to a partial overvoltage phenomenon during electrolytic degreasing. In order to be used as a high-nickel cathode, it seems that the current must be uniformly distributed on the surface of the substrate during plating.
4,000원
5.
2023.02
구독 인증기관 무료, 개인회원 유료
The shell & tube-type heat exchanger has been frequently used because it shows simple structure, easy manufacturing and wide operation conditions among many heat exchangers. This study aims to investigate the characteristics for thermal flow of coolant and the possibility of damage for tube equipped with shell due to thermal stress. For these purposes, The thermal flow of coolant in tube was simulated using ANSYS-CFX program and thus the behaviors of coolant were evaluated with standard k-ε turbulence model. As the results, as the flow rate of coolant in tube was increased, the mean relative pressure was also increased with quadratic curve, however, as the surface temperature of tube was increased, mean temperature difference was linearly increased. Finally it showed that the damage of tube could be predicted, that is, which tube was the most weak due to thermal stress.
4,000원
6.
2023.02
구독 인증기관 무료, 개인회원 유료
The purpose of this research is to investigate the statistical behavior of fatigue crack propagation(FCP) in magnesium alloy AZ31. FCP tests have been performed on compact specimens of AZ31 at load ratio conditions and maximum fatigue load conditions to obtain statistical data of FCP. It was found that the variability of fatigue crack propagation rate was significantly large at initial stage of FCP and gradually became smaller as the fatigue crack propagated. The finding of the study showed that increasing the load ratio could increase the variability of fatigue crack propagation rate at initial FCP stage. The samller the load ratio, the higher the fatigue crack propagation rate at initial stage. It was also found that the load ratio is a factor affecting the fatigue crack propagation rate in magnesium alloy.
4,000원
7.
2023.02
구독 인증기관 무료, 개인회원 유료
As the demand for aesthetic orthodontic treatment increases, the use of self-ligating ceramic brackets is increasing. For stable treatment, there should be no fracture or deformation of the self-ligation ceramic bracket door. Therefore, considering the situation in which labial displacement of teeth occurs in the orthodontic treatment stage. For this study, a model of the mandibular anterior region of a ceramic self-ligating bracket with a passive sliding door mechanism was selected. The measured tensile force data was substituted into the simulation analysis conditions, and the tensile force, stress distribution, and deformation values were analyzed using the finite element method. Using this, it is able to use the design elements of the orthodontic bracket that should be considered as design inputs in the development stage.
4,000원
8.
2023.02
구독 인증기관 무료, 개인회원 유료
Thin-film shape technology is recognized for its core technology to enhance the technology of LCD, PDP, semiconductor manufacturing processes, hard disks and optical disks, and is widely used to form coated thin films of products. In addition, resistance (electron beam filament) technology for heating is used to manufacture filament for ion implants used in semiconductor manufacturing processes. By establishing an electronic beam filament production system and developing seven specifications of electronic beam filament, it is contributing to improving trade dynamics and increasing exports to Japan through localized media of theoretical imports to domestic companies. In this study, CAE analysis was performed after setting electron beam filament specification and development objectives, facilities and fabrication for electron beam filament production, electron beam filament JIG & fixture design and fabrication followed by electron beam filament prototype. Then, the automation and complete inspection equipment of the previously developed electronic beam filament manufacturing facilities was developed and researched to mass-produce them, to analyze and modify prototypes, design and manufacture automation facilities, and finally, to design and manufacture the complete inspection equipment. In this paper, design and manufacture of electronic beam filament automation facilities for mass production were dealted with.
4,000원
9.
2023.02
구독 인증기관 무료, 개인회원 유료
In the wire constituting the LIN, which is one of the vehicle communication devices, disconnection of the wire or contact resistance of the circuit occurs due to vibration and aging of the vehicle. This affects the entire communication network and may have a significant impact on the safe driving of the vehicle as information is not transmitted. In this study, a LIN BUS circuit simulator was built on its own like a real car and measured with an automotive oscilloscope instead of a common method of measuring and diagnosing a circuit with a multimeter in the event of a LIN BUS circuit failure. Referring to the experimental results, it will be possible to diagnose faults in circuits efficiently and quickly.
4,000원
10.
2023.02
구독 인증기관 무료, 개인회원 유료
Recently, Regulations on ships exhaust gas are being strengthened. Nations around the world are trying to various efforts in many aspects to decrease ship emission gas. As part of these efforts, the shipping industry is working towards establishing green system that reduce the emission gas emitted in port. In this study we measured exhaust emission gases such as by fuel change using A-Ra Training Ship in Port. When sailing, we found that was 3.6% to 6.6% higher when using LRFO compared to using MGO, and during departure and arrival, the load changes were significant. As a result, was on average 29.8% higher and was 42% higher during departure, while was on average 19.5% higher and was 17.4% higher during arrival, with almost no difference in the other components.
4,000원
11.
2023.02
구독 인증기관 무료, 개인회원 유료
This research measured the change in mechanical characteristics of a sample obtained by finishing a metal coating to an engineering plastic manufactured using a 3D printer to satisfy both lightweight and quality characteristics. High-Temp material, which can be applied to space thermal environments with large temperature fluctuations, was applied as the engineering plastic material, and Stereolithography(SLA) method, which has relatively higher precision than Fused Film Fabrication(FFF) method, was selected as the manufacturing method. Electroless & electroplating were performed by metal coating on the surface to satisfy the characteristics of products requiring electrical conductivity. Tensile and bending tests were conducted to verify a change in the mechanical characteristics of a sample completed with a metal coating, and an adhesion test of the metal coating was also added.
4,000원
12.
2023.02
구독 인증기관 무료, 개인회원 유료
The automatic dust separator is a device installed in the suction tank of the pumping or drainage plant, and prevents foreign substances such as aquatic plants or wood chips from being sucked into the underwater pump. Since the dust separator obstructs the flow of water for separating dusts, a water level difference is likely to occur before and after the dust separator. Since the water level difference before and after the dust separator acts as an additional hydraulic load on the dust separator structure, it may reduce the lifetime of the dust separator and cause damage. In this study, in order to reduce the water level difference, we devised changing the existing I-beam-shaped dust separator parts to a streamlined shape, and quantitatively analyzed the water level difference before and after the dust separator, hydraulic load, and flow velocity distribution through computational fluid analysis to confirm the effect of design improvement.
4,000원
13.
2023.02
구독 인증기관 무료, 개인회원 유료
In this paper, a study was conducted on the analysis of communication circuit faults using oscilloscope waveform analysis. Circuit resistance was calculated based on voltage and operating current values using a simple equation, and it was confirmed that the increase in resistance of the communication circuit could be analyzed by analyzing the voltage level during transmitter operation. By combining information of the controller ID, the location of the fault was identified and it was concluded that the location of the fault can be quickly found by analyzing the oscilloscope waveform and the controller ID information. Additionally, the value of communication line contact resistance can be calculated using a simple equation, and the location of the fault can be found by analyzing the communication voltage level and ID information.
4,000원
14.
2023.02
구독 인증기관 무료, 개인회원 유료
Due to its excellent processability, thermal conductivity and high corrosion resistance, copper tubes applied to heat exchangers are being joined through brazing to increase heat exchange efficiency. In order to improve performance, the issue of joint quality of copper tubes, a major member of heat exchangers, is emerging, so research is needed to obtain excellent joint quality of brazing joints that may be damaged. In this study, the quality change of joints according to process variables was studied through induction heating brazing experiments using high frequency. The depth of penetration, which indicates the quality of the junction, was measured, and the center position of the high-frequency electrode and the height of the electrode, which change the location of the heat source applied to the junction, were selected as process variables. Lastly, the thermal image data obtained between the brazing experiments were obtained and the joint quality according to the temperature gradient of the joint was analyzed.
4,000원
15.
2023.02
구독 인증기관 무료, 개인회원 유료
Traffic accidents that occur while driving a car are inevitable, and the characteristics of the body repair field are that each vehicle accident has the same damage and no same repair conditions. Therefore, it is difficult to acquire know-how in vehicle body repair simply by theoretical method of textbook, and the repair method must be changed as new materials and new technologies are applied to it. In particular, roof panels are not frequently damaged by traffic accidents, but they are damaged by falling objects from the roof of a building or the opposite lane, resulting in roof bending and vehicle repair using dent repair to minimize VOC and reduce costs. In this study, the optimal maintenance method is proposed by analyzing the time, cost, and waste generation according to the work method when the degree of damage is large and replacement is required
4,000원
16.
2023.02
구독 인증기관 무료, 개인회원 유료
Thin-film shape technology is recognized for its core technology to enhance the technology of LCD, PDP, semiconductor manufacturing processes, hard disks and optical disks, and is widely used to form coated thin films of products. In addition, resistance (electron beam filament) technology for heating is used to manufacture filament for ion implants used in semiconductor manufacturing processes. By establishing an electronic beam filament production system and developing seven specifications of electronic beam filament, it is contributing to improving trade dynamics and increasing exports to Japan through localized media of theoretical imports to domestic companies. In this study, CAE analysis was performed after setting electron beam filament specification and development objectives, facilities and fabrication for electron beam filament production, electron beam filament JIG & fixture design and fabrication followed by electron beam filament prototype. Then, the automation and complete inspection equipment of the previously developed electronic beam filament manufacturing facilities was developed and researched to mass-produce them, to analyze and modify prototypes, design and manufacture automation facilities, and finally, to design and manufacture the complete inspection equipment. In this paper, analysis and modification of prototypes of electron beam filaments for mass production were dealted with.
4,000원
17.
2023.02
구독 인증기관 무료, 개인회원 유료
This study aims to explore the appropriate water pressure control of water supply pipeline to reduce water losses of water supply network in Jinan-gun. The current water pressure status of each 5 blocks and the impact of optimized water pressure on improving revenue water rate were investigated. In order to obtain the flow rate and water pressure data of each small block, a smart hub is set in the pressure reducing valve chamber at the inlet of the small block, and a smart water pressure meter is installed in the fire hydrant and the faucet of the customer. For the pressure reducing valves installed for water pressure management system of each block, the diameter calculation standard and type of the pressure reducing valve are determined, and the application reasons are put forward. The analysis results of water pressure management for each small block in Jinan-gun show that the pressure control equipment and water pressure management need to be improved in four small blocks. The water flow rate in Jinan-eup and Sangjeon-myeon increases from 57.2% to 87.6% when the water pressure control is completed.
4,000원
18.
2023.02
구독 인증기관 무료, 개인회원 유료
Along with the development of the automobile industry, the materials and processing technology of parts have also developed. In particular, various materials have been developed and applied to automobile bumpers, which are directly related to crash safety. In particular, the application of composite materials is expanding for weight reduction. In this study, a new composite material made of a mixture of carbon fiber and aramid fiber was developed and the possibility of application to an automobile bumper was reviewed, and significant results were obtained.
4,000원
19.
2023.02
구독 인증기관 무료, 개인회원 유료
In this study, a study on the design of the rake shape of a rotary screener is conducted. The rake bar and rake of a rotary screener were designed, and three types for the rake shape were designed by changing the rake shape. Structural analysis was conducted in consideration of the vertical load applied when the narrow object was pulled up by the rake and the friction force applied underwater, and the more efficient type was verified by comparing the stress and strain applied to the lake by shape. In addition, structural analysis was additionally performed by changing the material of the rake to a carbon composite material in the same manner. That is, in order to improve the need to replace the entire rake part in case of damage, we will examine the improvement of the strength of the rake by performing structural analysis by changing the material of the rake.
4,000원
20.
2023.02
구독 인증기관 무료, 개인회원 유료
In this study, measurement errors of the X and Y axes were verified by using an 80-100 mm gauge block, an NPL type angle measuring device, and a spelling on a contact-type 3D measuring device surface plate. In addition, the measurement specimen was repeatedly measured 10 times at 10° intervals from 0° to 40° to confirm the average value and standard deviation. After confirming the statistical test value (P) through ANOVA analysis of the statistical program, the correlation between angle change and error was confirmed.
4,000원
