• Journal of Korean Neurosurgical Society
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• 제54권4호
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• pp.275-279
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• 2013

Objective : This study was designed to determine the most reliable cephalometric measurement technique in the normal population and patients with basilar invagination (BI). Methods : Twenty-two lateral radiographs of BI patients and 25 lateral cervical radiographs of the age, sex-matched normal population were selected and measured on two separate occasions by three spine surgeons using six different measurements. Statistical analysis including intraclass correlation coefficient (ICC) was carried out using the SPSS software (V. 12.0). Results : Redlund-Johnell and Modified (M)-Ranawat had a highest ICC score in both the normal and BI groups in the inter-observer study. The M-Ranawat method (0.83) had a highest ICC score in the normal group, and the Redlund-Johenll method (0.80) had a highest ICC score in the BI group in the intra-observer test. The McGregor line had a lowest ICC score and a poor ICC grade in both groups in the intra-observer study. Generally, the measurement method using the odontoid process did not produce consistent results due to inter and intra-observer differences in determining the position of the odontoid tip. Opisthion and caudal point of the occipital midline curve are somewhat ambiguous landmarks, which induce variable ICC scores. Conclusion : On the contrary to other studies, Ranawat method had a lower ICC score in the inter-observer study. C2 end-plate and C1 arch can be the most reliable anatomical landmarks.

• 생물환경조절학회지
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• 제13권1호
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• pp.26-32
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• 2004

본 시험은 7${\sim}$9월 수확을 위한 고랭지 오이의 비가림 재배시 생력형 유인방법인 아치식의 재배방법을 개발하고자 실시하였다. 아치식의 유인높이(1.5 m, 1.8 m 및 2.1 m), 재식거리(90${\times}$40 cm, 90${\times}$50 cm 및 90${\times}$60 cm) 및 적심절위(20절, 25절, 30절, 35절 및 무적심)를 비교하였다. 비가림하우스 내 지표면 위 2.1 m의 기온은 37$^{\circ}C$로 너무 높아, 2.1 mrn에서는 일소현상이 나타났다. 아치식 유인높이 1.8 mrn가 다른 유인높이에 비해 착과율과 상품율이 높았다. 상품수량은 1.8 m에서의 102,691 kg ${\cdot}$ $ha^{-1}$로 1.5 mrn의 84,790 kg ${\cdot}$ $ha^{-1}$보다 21% 많았다. 재식밀도가 높을수록 노균병 발생율은 증가되었다. LAI는 적심절위가 올라갈수록 높았으며 내부투광율은 재식밀도가 좁을수록 경엽이 밀집되어 낮아졌다. 착과수는 주지보다 측지가 많았으며, 적심절위가 낮을수록 증가하였다. 상품수량은 90${\times}$50 cm, 35절 적심구가 98,311 kg ${\cdot}$ $ha^{-1}$로 90${\times}$40cm, 30절 적심구의 93,807 kg ${\cdot}$ $ha^{-1}$보다 5% 증가되었다. 따라서 여름생산을 위한 고랭지에서 오이의 아치식유인 재배시 유인높이는 1.8 m, 재식거리는 90${\times}$50 cm 및 적심절위는 35절이 최대의 수량을 얻을 수 있는 재배시스템으로 생각되었다.

• Journal of Chest Surgery
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• 제40권1호
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• pp.25-31
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• 2007

배경: 대동맥궁 치환 수술 시 뇌 보호법은 필수불가결하며, 다양한 방법이 시도되고 있다. 이중 순행성 뇌관류법의 이용은 완전 순환 정지시간을 최소화하고 뇌관류를 가능하게 하여 중추신경계 합병증을 줄일 수 있는 방법 중의 하나이다. 본 연구의 목적은 우액와동맥을 통한 순행성 뇌관류를 이용하여 대동맥궁 치환술을 시행한 환자들의 임상 결과를 조사하는 데 있다. 대상 및 방법: 2004년 7월부터 2006년 7월까지 대동맥궁 치환 시 대동맥궁 분지의 전부 혹은 일부를 치환 후 우액와동맥을 통한 순행성 뇌관류를 시행하면서 대동맥궁 치환을 한 11명의 환자를 대상으로 하였다 남자 환자는 9명, 여자 환자는 2명이었다. 수술 당시의 진단은 A형 대동맥 박리(5/11, 45.5%), A형 벽내혈종(1/11, 9%), 대동맥류(5/11, 45.5%)였고, 평균 나이는 $60.3{\pm}12.8$세였다. 우액와동맥으로 삽관하여 심폐기 가동 후 초저체온 상태(평균 최저 비인두 체온 $11.7{\pm}1.0^{\circ}C$)에서 완전순환정지를 시행하였고, 이 기간 중 일부에서 역행성 뇌관류법을 시행하였다. 결과: 완전 순환 정지 시간은 $31.1{\pm}16.9$분이었으며 역행성 뇌관류 시간은 $21{\pm}17.8$분이었다. 뇌관류를 위한 각각의 도관과 대동맥궁 분지를 연결하는 데 걸린 평균시간은 $24.1{\pm}9.3$분이었다. 술 후 사망 환자는(0/11, 0%) 없었고, 영구적 신경학적 합병증 또한 없었다. 결론: 더 많은 수의 환자와 장기적인 성적에 대한 연구가 필요하지만 우액와동맥을 통한 순행성 뇌관류를 이용한 대동맥궁 치환술은 대동맥궁 조작을 최소화하고 색전 및 전반적인 허혈에 의한 뇌합병증을 줄일 수 있는 방법으로 생각된다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1004-1005
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• 2006

The effect of tempering temperature and microstructure on dry sliding wear behavior of quenched and tempered PM with 0.3% graphite and 1-2% Ni steels was investigated. The sintered specimens were quenched from $890^{\circ}C$ and then tempered at $200^{\circ}C$ and $600^{\circ}C$ for 1 hr. Wear tests were carried out on the quenched$\neq$tempered specimens under dry sliding wear conditions using a pin-on-disk type machine at constant load and speed. The experimental results showed that the wear coefficient effectively increased with increasing tempering temperature and decreased with increasing Ni content.

• 대한치과교정학회지
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• 제23권4호
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• pp.671-691
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• 1993

To estimate the possibility in the application of TiN ion-plating to the orthodontic appliance, this study investigated frictional force and frictional coefficient between non-ionplated and TiN ion-plated to the orthodontic appliance. The obtained results were as follows : 1. For each group, the frictional force between metal bracket and arch wire in the wet condition was exhibited lower than that in the dry condition. 2. In the dry condition, the frictional force was lowest with fourth group, and it increased in the order of the 3rd, 1st, and 2nd group. Same situation happened in the wet condition. 3. Experimental results using ceramic & plastic bracket showed that group B was lower than group A, and group D was similar to group C. 4. The surface texture after experiment showed that the scratch due to a friction with bracket was observed in an arch wire of dry contition. Also the surface of bracket was rougher than before. 5. We observed that a specimen surface processed with the TiN ion plating was smoother than that of without the TiN ion plating. 6. The surface texture of a metal bracket and an arch wire in the wet condition was observed smoother than that in the dry condition. 7. In the dry condition, the friction coefficient of each specimen was very similar to each other, but in the wet condition, the friction coefficient of specimen processed with the TiN ion plating showed lower values.

• 한국공간구조학회논문집
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• 제16권1호
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• pp.85-94
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• 2016

In this study, an acceleration sensor that has optical fibers to measure the inclination and acceleration of a structure through contradictory changes in two-component FBG sensors was examined. The proposed method was to ensure precise measurement through the unification of the deformation rate sensor and the angular displacement sensor. A high sensitivity three-axis accelerometer was designed and prepared using this method. To verify the accuracy of the accelerometer, the change in wavelength according to temperature and tension was tested. Then, the change in wavelength of the prepared accelerometer according to the sensor angle, and that of the sensor according to the change in ambient temperature were measured. According to the test results on the FBG-based vibration sensor that was developed using a high-speed vibrator, the range in measurement was 0.7 g or more, wavelength sensitivity, 2150 pm/g or more, and the change in wavelength change, $9.5pm/^{\circ}C$.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.570-571
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• 2006

The mixed atomized iron powders with 0.3% graphite and 1% Ni powders were cold pressed and sintered at $1200^{\circ}C$ for 30 min under pure Ar gas atmosphere. Some of the sintered specimens were intercritically annealed at $760^{\circ}C$ and quenched in water (single quenching). The other sintered specimens were first fully austenized at $890^{\circ}C$ and water quenched. These specimens were then intercritically annealed at $760^{\circ}C$ and re-quenched in water. The experimental results showed that the wear coefficient effectively decreased in the double quenched specimen.

• 대한치과교정학회지
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• 제25권1호
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• pp.73-85
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• 1995

교정치료시 치축의 개선을 위한 많은 연구와 노력이 이루어져 왔다. 본 교실에서는 치축개선을 위해 MEAW를 응용한 Multi-Vertical Loop Arch Wire(MVLAW : 엠빌로)를 수년 전부터 다수치아의 치축을 동시에 개선코자 사용해 왔다. MVLAW는 일종의 근심경사된 치아를 세우는 장치로써 open vertical loop를 3가지 종류로 변형시켜 적용시켜 왔으며 이를 각각 A, B, C형으로 명명하였다. 각 MVLAW는 .017"x.025" TMAwire로 제작되며, A형 MVLAW의 경우 각 open vertical loop의 apex를 10도 정도 벌려주어 활성화시키며(electric welding stop을 각 loop의 근심측에 위치시킨다), B형과 C형 MVLAW의 경우 open vertical loop의 원심측에 10도의 tip back bend를 형성함으로써 활성화시킨다(B형의 경우 electric welding stop이 각 loop의 원심측에 형성되는 반면 C형의 경우 electric welding stop을 형성하지 않는다). 본 연구는 구치부의 치축을 동시에 개선코자할 때 MVLAW를 3가지 종류로 분류한 후 각 MVLAW의 효과를 알아보고자 상하악 1/2악을 광탄성 모형에 재현하여 그 응력분포를 관찰하여 다음과 같은 결론을 얻었기에 보고하는 바이다. 1. A형 MVLAW의 경우 3급 견인고무를 걸지 않았을 경우 하악 제1대구치와 제2대구치 치근의 원심면에서 강한 응력분포를 나타내나 전치부에 발생한 미약한 응력분포는 3급 견인고무의 장착으로 상쇄되었다. 따라서 A형 MVLAW는 초기에 치관의 직립효과가 있는 것으로 보인다. 2. B형 MVLAW의 경우 3급 견인고무를 걸지 않았을 경우 각 치아의 근심측에 응력분포를 보이며 견인고무를 걸었을 때와 비교시 전치부에 증가된 응력분포를 보였다. 따라서 B형의 경우 초기에 치근의 직립효과가 있는 것으로 보인다. 3. C형 MVLAW의 경우 3급 견인고무를 걸지 않았을 경우 하악전치부를 제외하고는 응력분포를 나타내지 않았으나 견인고무를 걸었을 경우 주로 견치와 소구치 근심면에서 응력분포를 보였다. 따라서 C형의 경우 견인고무 사용시 초기에 견치와 소구치에서 치근의 직립효과가 있는 것으로 보인다.

• Journal of Korean Neurosurgical Society
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• 제48권4호
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• pp.367-370
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• 2010

We present a case of posterior atlantoaxial screw-rod fixation in a patient with an aberrant vertebral artery (VA) course combined with bilateral high-riding VA. An aberrant VA which courses below the posterior arch of the atlas (C1) that does not pass through the C1 transverse foramen and without an osseous anomaly is rare. However, it is important to consider an abnormal course of the VA both preoperatively and intraoperatively in order to avoid critical vascular injuries in procedures which require exposure or control of the VA, such as the far-lateral approach and spinal operations.

• Journal of Ginseng Research
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• 제22권2호
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• pp.133-139
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• 1998

We have studied an activation mechanism of $pp60^{c-src}$ protein tyroslne kinase (PTK) by ginsenoside-$Rg_1$ (G-$Rg_1$ ) in NIH(pMcsrc/foc)B c-src overexpressor cells. It was previously reported that G--$Rg_1$ stimulated the activation of c-src kinase at 20 pM with a 18 hr-incubation, increasing the activity by 2-4-fold over that of untreated control, and this effect was blocked by treatments of in- hibitors of either protein synthesis (cycloheximide) or RNA synthesis (actinomycin D) (Hong, H.Y. et at. Arch. Pharm. Res. 16, 114 (1993)). However, an amount of c-src protein itself in wild-type cells was not changed by G-$Rg_1$. When the cells mutated at one or two tyrosine residue(s) (Y416/527) that are important sites to regulate the kinase activity were treated with G-$Rg_1$, increases both in the activity of c-src kinase and in the expression of the protein were not observed. In addition, removal of extracellular calcium ion by EGTA or inhibition of PKC by H-7 canceled the G-$Rg_1$-induced activation of the kinase. Although the activation was little affected by G-$Rg_1$ with a calcium ionophore A23187, it was synergistically stimulated by treatment of G-Rgl and PMA, a PKC activator. Taken together, these results suggest that the activation of c-src kinase by G-$Rg_1$ is caused by an increase in the specific activity of the kinase, but not in amount of it, and is involved with both collular calcium ion and PKC. Further the increase in the specific activity of c-src kinase may result from altered phosphorylation at tyro-416 and -527.