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
제23권 제5호 (2021년 10월) 38건
21.
2021.10
구독 인증기관 무료, 개인회원 유료
Due to environmental pollution, regulations on existing petroleum-based fuels are increasing day by day. LNG is in the spotlight as an eco-friendly fuel that does not emit NOx or SOx, but its boiling point is -163°C, so it needs to be handled with care. Materials that can be used at the above temperature are defined by IMO through the IGC Code. Among them, 9% nickel steel has great advantages in yield strength and tensile strength under cryogenic conditions, but it is difficult to use in arc welding such as FCAW for various reasons. This study is a study to apply fiber laser welding to solve this problem. As a previous study, this study conducted a study to find a welding heat source. After performing bead on plate welding, the optimal heat source was derived by analyzing the shape of the bead and adjusting the parameters of the heat source model. In this case, by applying the multi-island genetic algorithm, which is a global optimization algorithm, not the intuition of the researcher, accurate results could be derived in a wide range.
4,000원
22.
2021.10
구독 인증기관 무료, 개인회원 유료
Recently, traffic accidents have continued to occur due to the failure to secure a safe distance for trucks. Unlike passenger cars, freight cars have a large fluctuation in the weight of the vehicle's shaft depending on the load, and the fatality of accidents and the possibility of accidents are high. In this study, a braking distance prediction model according to the driving speed and loading weight of a three-axis truck was implemented to prevent a forward collision accident. Learning data was generated based on simulation, and a prediction model based on machine learning was implemented to finally verify accuracy. The extra trees algorithm was selected based on the most frequently used R2 Score among regression analyses, and the accuracy of the braking distance prediction model was 98.065% through 10 random scenarios.
4,000원
23.
2021.10
구독 인증기관 무료, 개인회원 유료
This study deals with the design of the marine antenna stabilization for an efficient 6 Degrees of Freedom(DOF) motion of a ship. Marine antenna must have abilities to target center and at the same time to stabilize the antenna dish in order to maintain its orientation toward the communication center. In order to achieve such requirements, structure stability and dynamics analysis to role to set up the simulation model. Prototype model designed and implemented into the DMU(Digital Mock Up) and MBD(Multi Body Dynamics) analysis method. Those simulation method has been carried out to stabilize the antenna under the ship motion. Simulation results show that the verification of structural stability better performance for marine antenna
4,000원
24.
2021.10
구독 인증기관 무료, 개인회원 유료
A Study on the Quality Prediction of Parts in the Multi-Stage Cold Forging Process Based on Big Data
In this study, as part of the paradigm shift for manufacturing innovation, data from the multi-stage cold forging process was collected and based on this, a big data analysis technique was introduced to examine the possibility of quality prediction. In order for the analysis algorithm to be applied, the data collection infrastructure corresponding to the independent variable affecting the quality was built first. Similarly, an infrastructure for collecting data corresponding to the dependent variable was also built. In addition, a data set was created in the form of an independent variable-dependent variable, and the prediction accuracy of the quality prediction model according to the traditional statistical analysis and the tree-based regression model corresponding to the big data analysis technique was compared and analyzed. Lastly, the necessity of changing the manufacturing environment for the use of big data analysis in the manufacturing process was added.
4,000원
25.
2021.10
구독 인증기관 무료, 개인회원 유료
This paper proposes a model predictive controller of robot manipulators using a genetic algorithm to secure the best performance by performing parameter optimization with the genetic algorithm. Genetic algorithm is a natural evolutionary process modeled as a computer algorithm and has excellent performance in global optimization, so it is useful for tuning control parameters. The sliding mode controller and inverse dynamics controller are included in the lower part of the model prediction controller to minimize the problems caused by non-linearity and uncertainty of the robot manipulator. The performance superiority of the proposed method as described above has been confirmed in detail through a simulation study.
4,000원
26.
2021.10
구독 인증기관 무료, 개인회원 유료
Recently, with the development of ultra-precision technology, the quality improvement of optical parts and various products is emerging. The need for a difficult-to-cut material that is light and exhibits high hardness and high strength physical properties is being emphasized. Ultra-precision machining processing solutions for these difficult-to-cut materials are being actively developed. In this research, experiments were performed using a DTM machine equipped with a laser-assisted machining module for ultra-precision machining of CaF2 materials that are brittle but exhibit high transmittance in a wide range from ultraviolet to infrared.
4,000원
27.
2021.10
구독 인증기관 무료, 개인회원 유료
This paper intends to consider the contents of the insufficient certification system of PAV and to propose the certification regulations. In other words, PAV is a combination of people and drones that should reflect commercial specifications among aviation certification specifications and civil aircraft regulations. However, the domestic PAV certification system is still lacking in clear detailed regulations, and the detailed certification system of PAV should be established as soon as possible. It is hoped that PAV certification system will be established first and applied in earnest in the future, and that the domestic PAV industry will be activated.
3,000원
28.
2021.10
구독 인증기관 무료, 개인회원 유료
Recently, the expansion of the travel market and the increase in demand for leisure sports because of the weekend travel culture following the implementation of the five-day week system, leisure activities such as fields related to hobbies are becoming a major part. In this study, floating body analysis was performed according to the wave direction of the hull to analyze the effect of the wave cycle of the leisure boat. The research target boat is a 24ft-class leisure boat with a capacity of up to 6 passengers and operating at a maximum of 25 knots. Existing boats reduce the stern trim by installing interceptors, but in this study, they were not installed in order to evaluate the effect of waves. Floating body analysis was performed to evaluate the effect of waves, and the conditions necessary for the analysis were set based on the shipping environment, and the effect of the wave cycle was analyzed. this study verified the stability and stability of the leisure boat about waves, and Based on the result data, propose a management measure to efficiently reorganize the internal structural reinforcement.
4,000원
29.
2021.10
구독 인증기관 무료, 개인회원 유료
Road surfaces and tires have a great influence on road noise in automobiles. Therefore, this study attempted to investigate the effect of changes in road surface and tire tread on road noise. For six road surfaces, road noise was measured and analyzed while changing two types of tire treads. In all frequency bands, the sound pressure of the road surface with a relatively large roughness was higher than that of other roads. And in the case of a road surface with relatively large pore, it was investigated that noise was reduced compared to other road surfaces due to the sound absorption effect in the low frequency area. On roads with irregular road roughness, the high sound pressure was exhibited in all frequency bands regardless of tire tread, indicating an increase in road noise due to irregular wear on roads. It was confirmed that the noise deviation due to the change in road surface was larger than the noise deviation due to the tire structure, and it is judged that noise research according to the structure and condition of the road surface.
4,000원
30.
2021.10
구독 인증기관 무료, 개인회원 유료
Electrospinning, as one of the nano technologies for synthesizing nanofiber, is widely used in filtration, thermal insulation, protective clothing, sensors, conducting devices, and other fields due to its simple equipment, low cost and easy manipulation. The electrospun fibers have small diameter, high porosity, excellent pore interconnectivity, large specific surface area, easy surface modification, polymer chain functionalization and other advantages. Therefore, in this study, electrospinning technology was employed to synthesize multifunctional composite nanofiber membrane(polyacrylonitrile/fly ash/polyacrylonitrile, PAN/FA/AgNO3), which has the ability to remove volatile organic compounds(VOCs) and heavy metals; moreover, the membrane also has excellent antibacterial ability. This research result provides an important reference value for broadening the application of electrospinning technology in the field of air and water filtration in the future.
4,000원
31.
2021.10
구독 인증기관 무료, 개인회원 유료
Driving safety of a semi-trailer is greatly reduced when driving in a section with a narrow turning radius, so a dynamic study of driving and road conditions is required. In this study, the driving stability of the semi-trailer was investigated using the RecurDyn program in consideration of the velocity and weight of the semi-trailer in the entrance curve section of the highway, and the turning angle and radius of the curved road. In order to select the model and analysis conditions according to the road type, the sloping curved road was modeled by selecting the curvature, entry length, height difference, and entrance angle of the curved section. From the analysis results, the higher the semi-trailer's entrance velocity, the heavier the weight, the narrower the entrance angle of the curved road, and the smaller the curvature, the greater the semi-trailer's maximum running angular speed which had an effect on driving stability.
4,000원
32.
2021.10
구독 인증기관 무료, 개인회원 유료
Recently, air pollution from fossil fuels is at a serious level, and the IMO proposes to reduce greenhouse gas emissions by about 70% by 2050, and controls greenhouse gas emissions by applying the energy efficiency disign index(EEDI) to each ship type. In this study, the marine fuel oil viscosity of MGO, MDO, HFO and CGO according to the temperature change was compared and measured and the difference was analyzed. As a result, the viscosity of CGO was 3.32mPa·s, which was almost similar to MGO(3.40mPa·s) and MDO(3.51mPa·s) so it was judged that it could be used as a marine fuel, and it was found that there was a significant difference with HFO at P<0.01 there was.
4,000원
33.
2021.10
구독 인증기관 무료, 개인회원 유료
In this study, we verify the stability of the operation of mechanical dust remover by conducting the development of a rack-type operating structure and mechanism. This led to the development of a new type of mechanical dust remover, which resulted in the following conclusions. The optimum design was established for the specifications and shapes of the main structural and power transfer components according to the required capabilities of the mechanical dust remover. The power transmission structure of the worm gear and the spur gear corresponding to the rack bar gear box was determined to fit the lift structure, which is a combination of rack sprockets. When the rack bar is elongated, it develops a rack-type operating structure that enables smooth descent by allowing it to form a gap between the rake and the screen. And the mechanism was verified by calculating the stresses on the sprocket entering the rack box.
4,000원
34.
2021.10
구독 인증기관 무료, 개인회원 유료
Molds are actively used for mass production of products such as mobile phones. Molds are required to be durable and have a high level of surface roughness. Therefore, the optimization of mold processing is essential. In this study, the cutting processing of SDP20 steel used in molds was analyzed and optimized. This study is expected to contribute to the improvement of product productivity to which plastics are applied.
4,000원
35.
2021.10
구독 인증기관 무료, 개인회원 유료
The strengthening of environmental regulations has raised interest in alternative energy and electric car. Secondary batteries are such energy storage device, and in this study, a secondary batteries production equipment parts will be manufactured. To this end, molds were designed and manufactured using numerical analysis. The reliability of analysis is to be confirmed through tensile tests and X-ray tests of products cast with manufactured molds. As the results of the casting method design parts was obtained as the average ultimate tensile strength of 178.23N/mm2, 173.85N/mm2 was recorded and good test results were achieved. It is considered that aluminum alloy research and heat treatment technology development should be carried out in the future.
4,000원
36.
2021.10
구독 인증기관 무료, 개인회원 유료
Combat vehicles were developed in two types depending on the purpose of operation. The body of the vehicle is relatively large welded structure, and there is a quality problem in that welding deformation occurs in a certain area. Welding deformation is a problem that is inevitably generated during the welding process, and additional corrective work is performed. However, due to the structural characteristics of the welded structure of combat vehicl, there are many limitations in the correction method, which lowered the productivity. To improve this problem, we intend to establish improvement measures through analysis of the areas where welding deformation occurs and apply corrective measures suitable for welding structures of combat vehicles. For the design improvement plans, the finite element analysis were used and the correction method were applied to simulated structure to confirm the possibility. Finally, the improvement effect was confirmed by manufacturing the actual welded structure. Based on the results of this study, it is expected that the productivity of related similar welding structures as well as structures of wheeled armored vehicles, can be improved.
4,000원
37.
2021.10
구독 인증기관 무료, 개인회원 유료
Domestic dust remover began to be manufactured and installed in the late 1980s by introducing Japanese products and technologies. Currently, the design standards of dust remover are applied to Japan's design standards and partly sub-unit technology was developed for the domestic environment, but no technology was not developed. In addition, most of the manufacturers are small or small, so many of them have been installed and operated for 25 years because they develop small technologies such as parts deformation and functional addition rather than core technology development. Mechanical dust remover require about 70% of manufacturing costs compared to conventional hydraulic dust remover, which can reduce initial production costs, reduce maintenance costs due to low failure rates, and can be operated reliably. Existing hydraulic dust remover had a problem of contaminating rivers due to leakage of hydraulic oil, but mechanical dust remover have no factors that cause water pollution. Therefore, this study developed a rack-type operating structure for optimal and new construction by developing a multi-stage rack structure of mechanical decontamination components, which are substitutes of conventional rotary and hydraulic dust remover.
4,000원
38.
2021.10
구독 인증기관 무료, 개인회원 유료
In the field of length, a gauge block is one of the representative gauges used as a standard for length. The main management items of the gauge block are central length, flatness, parallelism, hardness, and surface by visual inspection. The surface of the gauge block may wear over time due to repeated wringing. This phenomenon may deteriorate the precision accuracy and affect the reliability of the measurement results. In this study, the parameters of the surface roughness of the gauge blocks used repeatedly for about 10,000 hours were analyzed. The paired t-test of population mean difference was compared by using the gauge block that has changed over the years as a preliminary experiment and the gauge block with little frequency of use for less than 1 year as the reference value.
4,000원
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