• Journal of the Korean Arthroscopy Society
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• v.2 no.1
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• pp.40-44
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• 1998

The use of autogenous tissues is preferred for knee ligament reconstruction. However allografts play a role in major ligament reconstructive procedures in which multiple substitutions or revisions are required. In the dislocated knee, allografts may offer an advantage in reconstructing the PCL. But allografts in knee ligament surgery must be considered in terms of biomechanical and regenerative properties, disease transmission and immunogenecity, and methods of preservation and sterilization. Also only a few authors have described the use of allograft for reconstruction of a ruptured PCL, either a single procedure, or in combination with ACL repair following knee dislocation. Furthermore, the problems that the clinician faces with use of allografts is the necessity for supervision to ensure that the grafts are correctly processed, secondarily sterilized, and free of transmissible diseases. For these reasons, the routine use of allograft materials in the treatment of ligament deficiencies should be avoid and provide with meaningful outcome studies, including longterm follow-up.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.435-440
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• 2001

The purpose of this study was to evaluate mesh size and water velocity for the growth of filamentous periphytic algae(FPA). The growth experiment was carried out in the constructed pilot waterway system with nutrient-rich treated wastewater. Growth rate of FPA was highest at water velocity about 10 cm/s. The maximum standing crop of FPA was $253\;{\mu}g\;chl.a/cm^{3}$, and an average of the net productivity was $3.92\;mgDW/cm^{2}/day\;or\;25.3\;{\mu}g\;chl.a/cm^{2}/day$. Biomass development and growth rates of FPA were highest at the net with 20mm mesh size during the fall season and 10mm mesh size during the winter season.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.421-425
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• 2001

Among the many parameters describing water quality, total nitrogen content(TN) is regarded as important one in relation to water quality management of the waterbodies for its role in eutrophication process. This study evaluated for accuracy, convenience and promptness of nitrogen analysis methods : (1)UV spectrophotometric method, (2)summation method, (3)cadmium reduction method. And, the detection limit of each method was calculated using EPA method. The UV spectrophotometric method after oxidation appears to be more convenient and accurate in determination of the TN contents than the summation method and cadmium reduction method. The summation method is necessary to separate determinations of the organic nitrogen, ammonia, nitrite, and nitrate. And, because summation method has many other methods for each contents, it can be detected for wide range of concentration.

• 한국연소학회:학술대회논문집
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• 2000.05a
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• pp.85-92
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• 2000

End-gas temperatures were measured using CARS technique in a conventional DOHC spark-ignition engine fueled with PRF80. The measured pressure data were analyzed using band pass filter method. The measured CARS temperatures were compared with adiabatic core temperatures calculated from measured pressure. Significant heating by pre-flame reaction in the end gas was observed in the late part of compression stroke under both knocking and non-knocking condition. CARS temperatures measured at 10 crank angle degree before knock occurrence was higher than adiabatic core temperatures. These results indicate that there exist some exothermic reactions in low pressure and temperature region. CARS temperatures began to be higher than the adiabatic core temperature when the end-gas temperatures reached 700 K. The temperature elevation due to the pre-flame reaction correlated better with CARS temperature than with cylinder pressure.

• 한국연소학회:학술대회논문집
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• 2007.05a
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• pp.98-103
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• 2007

The number of vehicles employing diesel engines is rapidly rising. Accompanying this trend, application of an after-treatment system is strictly required as a result of reinforced exhaust regulations. The Diesel Particulate Filter (DPF) system is considered as the most efficient method to reduce particulate matter (PM), but the improvement of a regeneration performance at any engine operation point presents a considerable challenge by itself. Temperature, gas compostion and flow rate of exhaust gas are important parameters in DPF evaluation, especially regeneration process. Engine dynamometer and degment tester are generally used in DPF evaluation so far. But these test method couldn't reveal the effect of various parameters on real DPF, such as O2 concentration, amount of soot and exhaust gas temperature. This research has studied the possibility using dump combustor that used to take an approach lean premixed combustion in gas turbine for a DPF power and optimized. It is possible that utilize the system as DOC (Diesel Oxidation Catalyst) and SCR(Selective Catalytic Reduction) assessments test as well as DPF evaluation

• Proceedings of the KAIS Fall Conference
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• 2011.12b
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• pp.607-610
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• 2011

본 논문은 하이브리드 자동차 및 전기자동차의 고주파 발생시 전자파를 차단하는 역할을 하는 인버터 실드쉘의 단공정 스트립 레이아웃과 금형제작에 관한 연구이다. 현재는 일본에서 금형을 수입하여 7벌 단공정 금형방식으로 개발하여 65톤 프레스에서 시험생산하고 있는 중이다. 이에 본 논문에서는 단공정 금형의 스트립 레이아웃을 분석하여 프로그레시브금형설계 및 제작시 원가경쟁력을 갖추기 위하여 연구하였다.

• Environmental Analysis Health and Toxicology
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• v.19 no.4
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• pp.353-357
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• 2004

난황단백질인 비탈로제닌을 성숙한 암컷 붕어 혈청으로부터 음이온 교환 크로마토그래피를 이용하여 정제 하였다. 정제한 비탈로제닌을 BALB/c mice를 이용하여 폴리크로날 항체를 생산하였고 이를 protein A column을 사용하여 정제하였다. 또한 이렇게 정제된 폴리크로날 항체를 이용한 붕어 비탈로제닌 측정용 효소면역측정법을 개발하였으며 그 측정 범위는 2∼l,000ng/mL이고 recovery 변동 범위는 88∼112%였다. 또한 이 효소면역측정법을 평가하기 위해 성숙한 수컷 붕어를 1,000ng/L ethinylestradiol(EE$_2$) 에 4주 동안 노출시켜 유도되어지는 비텔로제닌을 측정하였다. 그 결과 성숙한 수컷 붕어의 경우 비탈로제닌이 3주 만에 암컷 붕어의 평균수치만큼 유도됨을 알 수 있었다.

• Proceedings of the KIPE Conference
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• 2004.07a
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• pp.384-388
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• 2004

High frequency common mode voltage produced by power inverters are a major cause of conducted EMI, creating motor ground currents, bearing currents and other harmful by products. This paper focuses on a new SVPWM method with random PWM injection to reduce conducted EMI noise. A New PWM technique associated with the common mode voltage can be significantly reducing and contributes to mitigate. The common mode voltage to $50\%$ in comparison with that for conventional SVPWM technique. Validation of the theory and reduction methods are then performed experiment ally based on an induction motor drive.

• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.562-564
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• 2008

This paper deals with the three phase high voltage power-grid connection topology using multi-level inverter. Due to the multi-level inverter, these are improved effect of fluctuating voltage, problem of EMC and switching loss using suitable switching patterns of device, above all thing, it is easy to realize the system because of using lower voltage rating switch. This topology can be applicable to power-grid connection of wind system, there is a good point about economical efficiency. The simulation results are presented to verify the validity of the proposed topology.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.473-475
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• 2006

FieldBus communication systems in industrial wired and wireless network may cause the degradation of the TCP performance due to the racket loss. TCP is particularly targeted at the wired networks, a packet loss is assumed to be caused by the network congestion. As a result, the performance of TCP decreases significantly when used over networks that exhibit a high bit error rate. In order to solve this problem, this paper designs and implements the WFSnoop mechanism which offers a fast local retransmission. The proposed mechanism does not require any changes in customer premises. Base on the simulation in the wired and wireless network environment, we analyzed the performance of the WFSnoop mechanism.