https://oak.chosun.ac.kr/handle/2020.oak/19140 Thu, 09 Apr 2026 19:06:06 GMT 2026-04-09T19:06:06Z https://oak.chosun.ac.kr/handle/2020.oak/19304 Title: 심부투열용 고주파 치료기의 제작과 RET 전극조건에 따른 온도 분포 특성 Author(s): 정재원; 김병주; 김기선 Abstract: A high-frequency therapy device with improved output by modifying a high-frequency stimulator was fabricated. The details of the design include generating part design, high-frequency transformer design, large output FET installation, DC voltage input part design and gate input driver design. Based on the real test using the pork meat, the temperature distributions according to the current electric transfer method, penetration depth, electrode diameter size were measured. In the CET method, the penetration depth was 0.5 cm and in the RET method, the penetration depth was 20 cm or more. In addition, it was confirmed that the temperature rise according to the penetration depth in the RET system was substantially constant, and the temperature rise was remarkable as the electrode diameter was small. As a result, it has been confirmed that the high frequency therapy device is highly affected by various conditions of the electrode. Sun, 31 Dec 2017 15:00:00 GMT https://oak.chosun.ac.kr/handle/2020.oak/19304 2017-12-31T15:00:00Z https://oak.chosun.ac.kr/handle/2020.oak/19307 Title: VE제안의 가치향상 유형별 수치적 범위기준 제시 Author(s): 남경우; 장명훈 Abstract: Since its introduction in Korea, design VE has widely been used as a means to enhance values in the construction industry. However, a greater emphasis is still placed on cost reduction in approach attitudes and performance evaluations on the implementation of design VE. In this regard, this study presented a performance evaluation method for cost, function, and value of VE proposals. Numerical criteria on the increase and decrease of cost and function that can classify the value enhancement type of VE proposals were proposed based on the performance evaluation method. It is expected that the use of numerical criteria for the type classification of VE proposal, and cost and performance evaluation method proposed in this study will make it possible to conduct a clear and more intuitive evaluation of VE proposal. However, it is appropriate to use the numerical criteria as a guideline to apply the new performance evaluation method for VE proposals. Therefore, it is necessary to conduct a statistical analysis with a wider range of users after the repeated application of the findings of this study, and thus to carry out research for presenting the numerical criteria for various types of users. Sun, 31 Dec 2017 15:00:00 GMT https://oak.chosun.ac.kr/handle/2020.oak/19307 2017-12-31T15:00:00Z https://oak.chosun.ac.kr/handle/2020.oak/19308 Title: 제강슬래그를 굵은 골재로 이용한 콘크리트의 동결융해 저항성 Author(s): 이효성; 한상호 Abstract: In this study, freezing-thawing resistance of concrete using steel slag as coarse aggregate(steel slag concrete) from Gwangyang Iron Co. was estimated to offer basic data for utilization of much more steel slag. Freezing-thawing test of concrete using crushed stone as coarse aggregate(crushed stone concrete) whose compressive strength and air contents are as close as possible to those of the steel slag concrete was performed. Because they are main two factors that affect of freezing-thawing resistance. The test was carried out up to 400 cycles according to KS F 2456. The compressive strength and weight of two concretes were measured and compared. As a result, the freezing-thawing resistance of steel slag concrete curing in water was almost the same with that of crushed stone concrete. But the resistance of steel slag concrete curing in air dry condition was weaker than that of crushed stone concrete. Also, the steel slag concrete which has more than 60% of W/C ratio showed much more surface degradation when compared to crushed stone concrete. Sun, 31 Dec 2017 15:00:00 GMT https://oak.chosun.ac.kr/handle/2020.oak/19308 2017-12-31T15:00:00Z https://oak.chosun.ac.kr/handle/2020.oak/19302 Title: 노즐을 적용한 흡기 매니폴드의 배출가스 고찰 Author(s): 김만재; 김태중; 최병기 Abstract: Exhaust gas from the combustion of automobiles adversely affects the human body and even pollutes the atmosphere. This study investigated the influence of exhaust gas change on intake manifold using the nozzle. First, the flow analysis was performed using the 3D flow analysis program. When the nozzle inlet air velocity increased, the average air velocity in the nozzle diameters of Φ2.5 and Φ5 increased 37.3% and 31.9% respectively at the intake manifold outlet. As the nozzle inlet air velocity increased, the maximum flow rate of air increased to 42.2% and 32.6%, respectively at nozzle diameters of Φ2.5 and Φ5. In order to verify the analysis results, experiments on the exhaust gas were performed in the engine simulation system. As the nozzle inlet velocity increased, HC values decreased by 42.4% and 31.4% at nozzle diameters of Φ2.5 and Φ5, respectively. And CO values decreased by 40.7% and 31.1% at nozzle diameters of Φ2.5 and Φ5. Sun, 31 Dec 2017 15:00:00 GMT https://oak.chosun.ac.kr/handle/2020.oak/19302 2017-12-31T15:00:00Z