• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.746-750
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• 2007

Vertebroplasty has drawn much attention as a medical treatment for the compression fracture of spine, which strengthens the vertebral body and corrects deformity, and relieves pain in patients by injecting bone cement. However vertebroplasty can cause fracture on adjacent vertebra due to relative stiffness change. This study involves the biomechanical evaluation of the vertebroplasty especially on adjacent vertebral body. The finite element method has been employed to analyze the patient who was treated vertebroplasty under static and dynamic loading. For this study, a three-dimentioal model of the three-level ligamentous lumbar segment ($L1{\sim}L3$)is created from medical image data (CT)and compared with the experimental results in vitro.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.101-102
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• 2006

345kV 변전소는 국내 전력계통의 근간으로서 고장 시계통 안정도에 미치는 영향이 크기 때문에 고장 제거가 착신하고 신속해야 한다. 따라서 345kV 변전소의 보호 장치들은 CT, PT, 차단기(trip coil), 보호계전기, DC전원 등이 모두 2계열화되어 있으며 보호 계전기는 각 계열마다 주보호와 후비보호가 따로 구비되어 있다. 본 논문에서는 34skv 변압기 보호용 보호계전기에 내장된 계전요소들의 유기적인 성능 검증을 할 수 있는 동특성 시험에 관한 기반 구축 과정 및 결과에 대해서 기술한다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.1943-1950
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• 2010

Superimposition of horizontal and vertical curves may hamper the ride comfort and the running stability of train and largely affect the maintenance cost. However, in many cases, it's not easy to make a track plan because of the fixed points (bridge, tunnel, turnout, catenary system, etc.) to be avoided due to the geographic conditions or to be passed for utilization of existing structures. In this study, when the horizontal and vertical curves are superimposed, in order to optimize the horizontal curve in aspect of the ride comfort, the object function $P_{CT}$ was developed and verified by vehicle dynamic analysis. Also, the solution algorithm for simplified evaluation method was presented.

• 한국정밀공학회지
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• 제20권12호
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• pp.205-212
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• 2003

Many people are exposed to accidents by vehicles or sports. The most frequent injuries by these accidents is concerned with a knee joint. The three-dimensional surface model of a knee is needed for dynamic analysis of knee motion and knee reconstruction. three-dimensional motion data of a knee joint were obtained using X-ray and precise magnetic sensors. The surface data of a femur and a tibia were obtained using cross-sectional pictures by CT. The three-dimensional surface models of a femur and a tibia were made by the method of optimal triangular patch. Using obtained motion data, we simulated the motion of three-dimensional knee joint model.

• Parasites, Hosts and Diseases
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• 제45권2호
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• pp.77-85
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• 2007

Among several diagnostic tools for clonorchiasis (Clonorchis sinensis infection), radiologic examinations are commonly used in clinical practices. During the 2 past decades, many reports regarding imaging findings of clonorchiasis were introduced. The basic imaging finding of clonorchiasis is diffuse dilatation of the peripheral intra-hepatic bile ducts, without dilation of the large intrahepatic or extrahepatic bile ducts. By this finding, however, active clonorchiasis cannot be differentiated from cured infection. Some recent radiologic studies suggested specific findings of active clonorchiasis. Besides direct demonstration of worms, increased periductal echogenicity on sonography and periductal enhancement on dynamic contrast-enhanced CT or MR imaging possibly represent active clonorchiasis. Those images of the liver clonorchiasis are known to be correlated with worm burdens (EPG counts) in their frequency and also severity. The images of cholangiocarcinoma associated with clonorchiasis show both the tumor with obstruction images and diffuse dilatation of the peripheral intrahepatic bile ducts. Radiological images can be a good practical alternative diagnostic method of clonorchiasis.

• Tuberculosis and Respiratory Diseases
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• 제57권5호
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• pp.489-493
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• 2004

일측성 폐동맥 형성부전증은 매우 드문 선천성 기형으로서 대부분 팔로사징, 심실중격결손등과 같은 선천성 심기형을 동반하며 선천성 심기형이 동반되지 않은 고립성 편측 폐동맥 형성부전증은 극히 드물다. 이러한 환자들의 경우 성인이 될때까지 무증상으로 지내는 경우가 많으며 흉부 방사선 검사상 병변측 폐의 폐음영은 과투과되어 나타나며 흉곽은 작아진 소견으로부터 고립성 편측 폐동맥 형성부전증을 의심하게 된다. 저자들은 경미한 운동시 호흡곤란을 증상으로 내원한 50세 여환에서 흉부 전산화 단층촬영 및 환기-관류 스캔과 심초음파검사를 시행하고, 삼차원 재구성 전산화 심혈관 단층촬영을 이용하여 고립성 우측 폐동맥 형성부전증을 진단하고 치료한 1례를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

• Archives of Plastic Surgery
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• 제38권6호
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• pp.775-782
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• 2011

Purpose: Nasal bone fracture is most common facial bone fracture. The cause of fractures is mainly trauma such as fighting, automobile accident and fall down, and it commonly involves young males. Very frequently nasal bone fractures are associated with other facial injuries such as orbital bone fracture, maxillary bone fracture and nasal septal deformities. Because of various dynamic directions of power are involved, phenomenon of fractures are also various and treatment cannot be simple. Methods: We studied and analyzed retrospectively 452 cases nasal bone fractures from January 2008 to December 2010. Diagnosis were made with physical examination, Nasal bone X-rays, Facial bone CT and 3D facial bone CT. Four surgeons are involved in treatments of these patients and applied different procedure along patient's condition and deformity. We analyzed the cause of nasal bone fractures, deformities, associate injuries and applied surgical technique, and patient's satisfaction rate. In this study, old nasal bone fractures were excluded. Results: Young male group was most commonly sustained nasal bone fracture and physical violence was most common cause of injury. 64 of 452 patient was involved associate injuries of face. Closed reduction were applied 246 cases and C-arm quide reduction were 167 cases and in 20 cases lateral osteotomy were applied. Approximately, more than 80% of the Patients were satisfied with the outcomes. Conclusion: Diagnosis and treatment of nasal bone fractures are considered simple but because of various deformity and associate injuries, treatment is not always simple and universal. Time to time, we face unsatisfied patient after treatment of nasal bone fractures. For obtaining satisfactory result, cause of injury and state of deformities and associate injuries such as nasal septal deformity should be evaluated properly and proper treatment should be applied.

• 대한방사선기술학회지:방사선기술과학
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• 제41권2호
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• pp.123-128
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• 2018

Recently, the use of contrast agents has been increasing as a broader range of tests and dynamic tests have become common due to the development of equipment and imaging techniques such as Multi-Detector CT. However, the side effects of using contrast agents have been reduced by the development of non-ionic contrast agents, but they are still occurring often. The purpose of this study was to propose a method to minimize the side effect of contrast agent by using the amount of contrast agent injected to the brain angiography test to suppress excessive use of contrast agent and analyze the amount of contrast agent. Patients who were prescribed Brain Angiography due to cerebrovascular disease, According to the results of the comparison of the results obtained by dividing into 4 groups of 10ml each according to the amount of contrast medium injected with contrast agent according to the BMI of the patient, BA and SNR were not different between groups, and even if the amount of contrast injection was reduced, there was no problem in the evaluation of CT angiography through 3D reconstruction. This result shows that even if the contrast medium is injected into the blood vessels of the patient first and then the contrast medium is used as the physiological saline solution, the contrast medium is reduced by 40% it can be expected to minimize.

• 대한정형외과 초음파학회지
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• 제3권1호
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• pp.38-46
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• 2010

고관절에 위치한 골, 관절 및 주위 연부 조직의 병변은 고관절의 통증을 유발할 수 있다. 이를 진단하기 위해 기초적인 이학적 검사와 단순 방사선 검사를 시행하고, 경우에 따라 CT, MRI 등을 이용하였다. 그러나 건과 점액낭 등의 연부조직 병변 대해서는 초음파 검사가 비침습적이고 역동적인 검사가 가능하고, 고관절에 대한 수술 후 추시 검사 수단으로도 사용할 수 있다. 그러나 성인의 고관절은 심부에 위치하여 그 검사가 힘들고 비만인 환자에게는 적용하기 힘든 경우도 있다. 이에 고관절 주위의 구조물들의 정상적 초음파 소견과 고관절 질환의 병적 소견을 알아보고 또한 기타 활용 방안에 대해 설명하였다.

• Nuclear Engineering and Technology
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• 제21권3호
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• pp.165-170
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• 1989

준 동적 파괴가 일어나는 변형율속도 조건에서 A533B-1 원자로 압력용기강의 파괴인성 및 파괴저항특성에 미치는 변형율속도의 영향을 균열선단의 강 소성역 관찰 및 파면의 미세거칠기측정을 통해 연구하였다. 1/2T-CT 파괴시편에서 약 1.5mm 이하의 균열진전에 대해서는 소성일로 부터 구한 J와 수정 J가 거의 일치하였다. 파면의 미세거칠기로부터 구한 국부 변형율은 1.8-2.0 정도의 값을 나타내어 거시적으로 측정된 값보다 높은 값을 보여주었다. 이들 방법은 모두 변형율속도가 증가함에 따라 파괴인성은 증가하나 tearing modulus는 큰 변화가 없음을 보여주었다.