• Journal of the Korea Convergence Society
• /
• v.10 no.9
• /
• pp.187-192
• /
• 2019

In this study, the structural and fatigue analyses were carried out according to the configuration of rear wheel suspension of torsion beam. Three types of models similar to the actual torsional beam suspension are analyzed and we will find out which one is best on strength. The models of torsion beam suspension were designed in three types of models A, B and C through CATIA program and the results of structural and fatigue analyses were obtained by using the ANSYS program. We will confirm which model is better structurally than other models. According to the analysis results, the deformation happens to be the largest in the middle, and model B has the least deformation compared to model A and C. Similarly, model B is shown to have the smallest result at equivalent stress. So, model B is judged to be the best in terms of its strength, and it is thought to be the most efficient to converge into art design at the suspension design with a torsion beam of rear wheel.

• Journal of the Korea Convergence Society
• /
• v.12 no.1
• /
• pp.199-204
• /
• 2021

In this study, the configurations of the two engine exhaust manifolds were designed. And the strengths and durabilities were analyzed through the structural analysis and natural frequency analyses of these models. As the result of structural analysis, the strength of model A is much better than that of model B because the maximum stress and deformation of model B are considerably greater than those of model A by more than 9 and 39 times, respectively. It can also be confirmed that model A has the durability better than model B because the maximum frequency of model A is greater than the natural frequency of model B and its maximum deformation is smaller than model B. The result of this study can be used to investigate the durability due to the exhaust manifold shape of medium-sized car without actual test. It also seems to be helpful in the aesthetic convergent design of small car muffler.

• Journal of the Korea Convergence Society
• /
• v.11 no.12
• /
• pp.131-135
• /
• 2020

In this study, the models with three, five and ten wings of the propeller which made a light aircraft fly were performed by air flow analyses. As for the flow model A with the shape with five wings, Model A can be seen to be the most ideal flow of air. The flow of air through the number of wings, which is not too many or too few, shows the most smooth flowing form. The smaller the number of propeller blades, the smaller the flow of air. Model A is applied under pressure of up to 0.5631 MPa at the front of air flow. Also, models B and C are applied under pressures of 0.5758 MPa and 0.5589 MPa, respectively. Comparing the pressure contours for each model of flux, model B can be shown to have the highest pressure distribution. The result of this study can be used to investigate the air flow without actual testing. It also seems to be helpful in the aesthetic convergent design of light aircraft propeller.

• Journal of the Korea Convergence Society
• /
• v.11 no.12
• /
• pp.155-159
• /
• 2020

In this study, the structural analyses were performed on the number of leaf springs in large truck. The deformations were small for all four models. The maximum stress of model A was found to be the largest, and that of model D was the smallest. Model A was seen about 1.87 times larger than model D and about 1.52 times larger than model B. The maximum stresses of models C and D were seen to be less. In terms of the effect to reinforce one more overlapping spring, The effect of the enhancement of the strength of model D was shown to be small by comparing with model C. Therefore, model C with three overlapping springs is thought to be efficient in design and good in strength. The structural strength of leaf spring can be evaluated by applying this study result to the leaf spring at large truck. And it is seen that the result can be the design of the leaf spring with durability at large truck and the aesthetic convergence.

• Journal of the Korea Convergence Society
• /
• v.12 no.2
• /
• pp.173-177
• /
• 2021

In this study, the torsional rigidity and durability of the stabilizer models with the hollow axis of light and large sized cars were compared and investigated each other. Model 1 was applied with the moment more than three times as much as model 2, but the maximum deformation of model 1 was seen to be about 2.6 times larger than that of model 2. Commonly, models 1 and 2 are seen to get the most stress at the neck of stabilizer bar link. Also, the maximum stress of model 1 was about 2.9 times larger than that of model 2. Model 1 at large car showed more than 20 times more deformed energy than model 2 at small car. Overall, it could be examined that the deformation energy of the bracket part on the side where the moment fixing the stabilizer bar was applied was greater than that of the stabilizer. It is thought that the analysis results in this study can be helped at the design of its convergent research as a durable component of the stabilizer at a light or large sized car.

• Safety and Health at Work
• /
• v.12 no.1
• /
• pp.74-95
• /
• 2021

Background: A job-exposure matrix (JEM) is an important surrogate indicator to evaluate past exposure levels. Although a Korean asbestos JEM has been constructed previously, this JEM includes only a few industrial and occupational groups. This study aimed to reconstruct the JEM by integrating the latest organized data to improve its utility. Methods: We used recent Korean standard industry and occupation codes and extracted 36 articles from a systematic literature review to initiate the reconstruction of the previous Korean asbestos JEM. The resulting data consisted of 141 combinations of industrial and occupational groups. Data from the Netherlands's JEM were also reviewed and categorized into 70 industrial and 117 occupational groups by matching with the Korean data. We also utilized Germany's data, which consisted of 10 industrial and 14 occupational groups. Results: The reconstructed Korean asbestos JEM had 141 combinations of industries and occupations. The time periods are from the 1980s to the 2000s in 10-year intervals. Most of the data were distributed between the 1990s and the 2000s. Occupations with high exposure to asbestos included knitting and weaving machine operators, automobile mechanics or assemblers, ship mechanics or assemblers, mineral ore and stone products processing mechanics, and metal casting machine operators or mold makers. Conclusions: The reconstructed Korean asbestos JEM has expanded the type and duration of the occupational groups of the previous JEM and can serve as an important reference tool for evaluating asbestos exposure and designing compensation and prevention policies in Korea.

• Journal of the Korea Convergence Society
• /
• v.12 no.1
• /
• pp.171-176
• /
• 2021

The flow analysis by each configuration of automotive muffler in this study was carried out. And it aims at finding the design model that can increase the flow property best. It is shown that model B has the lowest maximum pressure and model C has the largest. Compared with the best flow rate according to the shape of the automotive muffler, model A had the comparatively smooth flow stream at the entrance and exit. However, model B has the largest flow rate in the muffler but the least flow rate in the exit, making it look less efficient. By the flow analysis result according to the muffler configuration, it is thought to design the muffler effectively by looking for the model with more smooth flow. The result of this study can be used to investigate the flow according to the configuration of small car muffler without actual test. It also seems to be helpful in the aesthetic convergent design of small car muffler.

• Journal of the Korea Convergence Society
• /
• v.12 no.2
• /
• pp.215-219
• /
• 2021

The flow analyses around the wing of airplane installed with winglet or sharkelt were carried out in this study. At the model without winglet, it can be seen that the air flows beside the wing and the flow is concentrated at the end of wing. At the model of winglet or sharklet, the pressure on the bottom of the wing happens to be lower in the wide area than for model without winglet. At the analysis result, the air flowing next to the wing can be seen to go over and rotates over the main wing. The model with the sharklet shows that the flow rate is the fastest. In case of model with sharklet, it is thought that the maximum total pressure of flow is distributed at the bottom of the wing, which can further improve the lift force of the wing. It is thought that the analysis results in this study on the air flow due to the configuration of aircraft edge wing can be helped at its convergent research.

• Design & Manufacturing
• /
• v.15 no.4
• /
• pp.24-31
• /
• 2021

In this study, an artificial neural network model was constructed to convert CAE analysis data into similar experimental data. In the analysis and experiment, the injection molding data for 50 conditions were acquired through the design of experiment and random selection method. The injection molding conditions and the weight, height, and diameter of the product derived from CAE results were used as the input parameters for learning of the convert model. Also the product qualities of experimental results were used as the output parameters for learning of the convert model. The accuracy of the convert model showed RMSE values of 0.06g, 0.03mm, and 0.03mm in weight, height, and diameter, respectively. As the next step, additional randomly selected conditions were created and CAE analysis was performed. Then, the additional CAE analysis data were converted to similar experimental data through the conversion model. An artificial neural network model was constructed to predict the quality of injection molded product by using converted similar experimental data and injection molding experiment data. The injection molding conditions were used as input parameters for learning of the predicted model and weight, height, and diameter of the product were used as output parameters for learning. As a result of evaluating the performance of the prediction model, the predicted weight, height, and diameter showed RMSE values of 0.11g, 0.03mm, and 0.05mm and in terms of quality criteria of the target product, all of them showed accurate results satisfying the criteria range.

• Journal of Radiation Protection and Research
• /
• v.47 no.3
• /
• pp.152-157
• /
• 2022

Background: The hemi-body electron beam irradiation (HBIe^-) technique has been proposed for the treatment of mycosis fungoides. It spares healthy skin using an electron shield. However, shielding electrons is complicated owing to electron scattering effects. In this study, we developed a thimble-like head bolus shield that surrounds the patient's entire head to prevent irradiation of the head during HBIe^-. Materials and Methods: The feasibility of a thimble-like head bolus shield was evaluated using a simplified Geant4 Monte Carlo (MC) simulation. Subsequently, the head bolus was manufactured using a three-dimensional (3D) printed mold and Ecoflex 00-30 silicone. The fabricated head bolus was experimentally validated by measuring the dose to the Rando phantom using a metal-oxide-semiconductor field-effect transistor (MOSFET) detector with clinical configuration of HBIe^-. Results and Discussion: The thimble-like head bolus reduced the electron fluence by 2% compared with that without a shield in the MC simulations. In addition, an improvement in fluence degradation outside the head shield was observed. In the experimental validation using the inhouse-developed bolus shield, this head bolus reduced the electron dose to approximately 2.5% of the prescribed dose. Conclusion: A thimble-like head bolus shield for the HBIe^- technique was developed and validated in this study. This bolus effectively spares healthy skin without underdosage in the region of the target skin in HBIe^-.