• Korean Journal of Computational Design and Engineering
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• v.3 no.3
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• pp.168-176
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• 1998

This paper deals with an application on the mould machining of air intake hose product by using 3-dimensional parametric modeling techniques. The detailed domain is the 3-dimensional product with similar shapes and different sizes which needs too much working time for preparation of modeling or machining due to making a trial and errors repeatedly. Decision making rules for selection of modeling order and technique, and for calculation of cutting conditions, and for determination of sequence and method concerning machining operations are required by interview of expert engineers in the field. The developed expert system of modeling and machining is programmed by using a user programming language under the CAD/CAM software of the Personal Designer. The developed system that aids a mould engineer who is working in the modeling and machining section which deal with air intake hose product provides strong and useful capabilities.

• Journal of the korean Society of Automotive Engineers
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• v.8 no.1
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• pp.75-86
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• 1986

This paper describes a simulation program of intake and exhaust processes in a 4-stroke S.I. engine and also studies the relationship among various engine parameters under different engine speed and load conditions. This simulation program includes the engine cylinder model for the intake and exhaust processes and its formulation and evaluates the system characteristics such as inlet mass, pumping work and residual gas in the cylinder-which influence on power output, fuel economy and exhaust emissions. In order to evaluate the accuracy of the simulation program, predicted results were compared with the experimental data obtained on the 4-stroke, 4-cylinder gasoline engine and satisfactory agreement was obtained.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.11a
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• pp.182-186
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• 2000

The porous woven hose is recently considered as an effective element of automotive intake systems. In order to predict the acoustic performance of an intake system with a porous woven hose, the information on the acoustic wall impedance is required. In this article, a measurement technique that is valid over the low frequency range and without mean flow condition is presented. The measurement is performed in a cylindrical chamber with a concentric layout of the sample and the resistance is estimated from measured reactance and transmission loss data. It is observed that the measured transmission loss for a porous woven hose with an arbitrary length agrees well with the predicted one that uses the estimated impedance for a small sample length.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.12
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• pp.1964-1967
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• 2021

Recently, to improve the effectiveness of education to learn from textbooks, immersive 3D environments such as virtual reality(VR) has been widely used for education. In this paper, in order to intuitively present education about content scenarios on changes in the human body according to food intake, we consist an immersive virtual reality environment to express the same life-size organs. The participants in our educational system showed higher results in all items compared to the existing textbook-based education such as immersion, understanding, and quality of education program. Also it was found the importance of interactivity to increase the effectiveness of immersive class.

• Journal of the East Asian Society of Dietary Life
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• v.15 no.6
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• pp.633-643
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• 2005

The purpose of study was to investigate nutritional supplements intake of elementary school students aged 7 to 12 years in Incheon The subjects were 631 mothers of schoolchildren and cross sectional study was conducted by a self-administered questionnaire. Nutritional supplements were taken by $42.3\%$ of the surveyed elementary school students. Among nutritional supplements they toot vitamin and mineral accounted for $47.3\%$, herbs and chinese medicine $39.3\%$ and dietary supplements $10.7\%.$ Among reasons for taking nutritional supplements, help for growth, health promotion, supply for deficient nutrients and prevention or treatment of disease were in order. As for the reasons for not taking nutritional supplements, most of the subjects answered that meals are enough in getting nutrients for children Mother of elementary school students usually Dew the health claim of the nutritional supplements before taking the Also they usually got the information of the nutritional supplements 1mm doctors or pharmacist and bought the nutritional supplements at drugstores, oriental medicine clinic and on-line shop in order. As for the effect of nutritional supplements, $43.7\%$ of the subjeces answered as 'effective' and $81.7\%$ of the mother of elementary school students who took nutritional supplements answered positively that they would continue to have their children take it Among the reasons they would continue to have their children take it help for growth ranked the first. therefore, these results my provide basic informations on nutritional supplements used by the elementary school students in Incheon.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.5
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• pp.739-745
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• 2008

This study was conducted to determine the salt-intake from meals that were served by an institutional foodservice establishment for a month. Meals (176) were classified into 12 food groups by CAN Pro 3.0. These consisted of bap 6, mandu 5, guk 29, jjigae 9, jjim 4, gui 8, jeon 5, bokeum 25, jorim 16, fried 7, namul 49, pickled 12. The average salt content of 100 g of each menu item was significantly higher in the order of pickled>jorim>bokeum>gui>namul>jeon>jjigae>jjim>fried. The average salt and sodium contents of 1 potion of menu item was significantly higher in the order of jjigae>mandu>guk>bap>jorim>pickled>bokeum>gui>fried>jjim>gimchi>namul>jeon. The average salt contents of kim-chijjigae (6.05 g), eggjorim (7.01 g), cooked namul (2.78 g) and salted pepperleaves (4.67 g) was higher than that of the other menu items served frequently in the establishment. The average intake of salt and sodium was 23.48 g (sodium 9,310 mg) a day, 7.35 g (sodium 2,960 mg) with breakfast, 7.55 g (sodium 2,990 mg) with lunch and 8.33 g (sodium 3,300 mg) with dinner. The daily salt intake was slightly higher than that of DRIs (Dietary Reference Intakes).

• Applied Biological Chemistry
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• v.27
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• pp.18-28
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• 1984

In order to improve feed values of Korean agricultural by-products, various treatments including physical, chemical, physicochemical and fermentation were suggested in th is review article. Physical treatments such as chopping, grinding and pelleting reduce partiole size of agricultural by-products, and increase passage rate from the rumen, thus may increase voluntary feed intake and weight gain. Digestibility and voluntary feed intake of straw, rice hull and sawdust, also, may be increased by chemical treatment using sodium hydroxide or ammonia. Especially, because nitrogen content of by-products increase and toxic problem is not posed by ammonia treatment, it's practical usage is recommended in Korea. Silage or fermentation treatment using principles of microbial fermentation may improve palatability of low quality by-products. As mentioned above, it is concluded that various treatments suggested are desirable and improve feed value but may raise several problems. Unfortunately, because cost for installation and products is great and processing work is complicate, farmers are not using well these processing methods until now. Therefore, in order to increase the practical usage at farm level, it is thought that many research works be achieved for efficient process which have simple operation and low installation cost.

• 유체기계공업학회:학술대회논문집
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• 2001.11a
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• pp.76-80
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• 2001

Unsteady compressible Euler equation is solved and the high-order, high-resolution numerical solver, physical boundary condition, adaptive nonlinear artificial dissipation model and conformal mapping are applied to computation of steady transonic flow and unsteady acoustics. The acoustic characteristics of axi-symmetric duct and two dimensional straight/S channel are studied and the computation results shows good agreements with linear analysis. In transonic case, local time stepping and canceling-the-residual techniques are used for convergence acceleration. The aspect of flow and acoustics in S-channel and the Pattern of noise radiation is changed by inflow Mach no. and static pressure at fan-face.

• Journal of Environmental Impact Assessment
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• v.3 no.2
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• pp.33-45
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• 1994

Water quality of Chongju and Daejeon Water Intake Tower Region, embayments in Daechong Reservoir was found to be worse than that of main lake after analysis of water which were sampled during April, July, October in 1993. Concentration of COD and SS at those two water intake tower sites were 2.8-5.6 mg/l and 2.2-3.2 mg/l, higher than that of main lake. T-N concentration of those two sites was 1.1-1.9 mg/l similar to that of main lake, and T-P concentration of those two sites was 0.14-0.18 mg/l, higher than that of main lake. This study used water quality model of embayment which can analyse pollutant loads from stream and surrounding land use, advection, decay, and diffusion transport between embayment and main lake. The model can predict water quality of embayment according to the change of pollutant load, water elevation of embayment, quantity of water intake in order to suggest water quality management. This study suggests embayment water quality management alternatives, 1) construction of waste water treatment facilities at embayment and main lake for the decrease of pollutant loading, 2) water intake at main lake less polluted or eutrophicated than embayment, and 3) outflow elevation selection for polluted hypolimnion water outflow during stratification.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.6
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• pp.183-189
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• 2003

The study of the automotive noise reduction has been concentrated on the reduction of the automotive engine noise because the engine noise is the major cause of automotive noise. However, many studies of automotive engine noise led to the interest of the noise reduction of the exhaust and intake system. Recently, the active control method is used to reduce the noise of an automotive exhaust and intake system. It is mostly used the LMS(Least-Mean-Square) algorithm as an algorithm of active control because the LMS algorithm can easily obtain the complex transfer function in real-time. Especially, Filtered-X LMS (FXLMS) algorithm is applied to an Active Noise Control system. However, the convergence performance of LMS algorithm went bad when the FXLMS algorithm was applied to an active control of the induction noise under rapidly accelerated driving conditions. So, in order to solve this problem, the modified FXLMS algorithm is proposed. In this study, the improvement of the control performance using the modified FXLMS algorithm under rapidly and suddenly accelerated driving conditions was identified. Also, the performance of an active control using the LMS algorithm under rapidly accelerated driving conditions was evaluated through the theoretical derivation using a chirp signal to have similar characteristics with the induction noise signal.