• Journal of Chest Surgery
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• v.31 no.8
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• pp.787-791
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• 1998

Materials and methods: Between 1979 and 1996, 27 patients with primary cardiac tumor underwent surgery at Catholic University Medical College. Mean age of patient was 45.1${\pm}$3.03 ranging from 21 to 67 years old. Twenty-four cases were myxomas, 2 cases were chondrosarcoma, and remained case was angiosarcoma. Diagnosis was confirmed by echocardiography, cardiac angiography, CT scan, and MRI. The most common site of tumor origin was fossa ovalis limbus area(17cases:63%). A biatrial operative approach was commonly used in 15 cases and the tumor was removed through left atriotomy site. Complete excision of the tumor with a cuff of normal tissue was performed. All heart chambers were carefully explored for evidence of multicentric myxomas or other tumor debris. Most of the patients were improved on postoperative period compared to preoperative NYHA functional class. Results: There was one operative death due to low cardiac output syndrome. Follow up period was 3 months to 17 years. There was 2 late deaths due to local recurrences. Conclusion: complete surgical excion is important for increasing cure rate. Malignancy cannot be ruled out even though preoperative echocardiography suggests benign nature. Chest CT or MRI is effective for further evalution in addition to echocardiography. In suspicious of malignancy, more extensive resection is essential and postoperative chemotheraphy or radiotherapy is useful.

• Journal of Yeungnam Medical Science
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• v.3 no.1
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• pp.67-72
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• 1986

Authors evaluated the accuracy of preoperative pelvic CT scan staging and its effects on management in 12 biopsy proved rectal cancer patients. Authors also studied postoperative CT in 5 patients to detect disease recurrence and metastasis. Preoperative CT staging was identical to surgical and/or pathological staging in 9 patients(75%), but it was underestimated in two cases and overstimated in one instance than in surgical stagings. In 7 cases, CT scan didnot alter original choice of procedures. However, preoperative CT staging gave definitive informations to change management plans in 5 cases otherwise the treatment would be difficult and inadequate. Postoperative CT showed local recurrence in one and liver metastases in 2 cases. One of them was not detected at exploratory laparotomy.

• Journal of the Health Care and Life Science
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• v.8 no.2
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• pp.121-125
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• 2020

People counting has always been a method of interest for maximizing energy saving by identifying the congestion level or amount of use of a specific facility to efficiently manage the facility, or automatically implementing a power saving function by identifying the number of people entering and exiting a specific place such as a toilet. The method of counting people by image processing is very expensive and has the disadvantage of being severely affected by the surrounding environment of the lighting. In the case of the area sensor, there is a disadvantage of counting as one person when the number of people passes close with arms folded. In order to solve the existing method, which is expensive, affected by lighting, or inaccurate the number of people in certain cases, this paper proposes a new method of counting people using the principle of LiADAR. Accurate counting of the number of people entering the hospital will help manage hospital facilities, but it will also help to establish effective quarantine measures at the present time when Corona 19 is prevalent.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.200.2-200.2
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• 2015

모바일 기기의 성장세로 인해 낸드 플래시 메모리에 대한 수요가 급격히 증가하면서 높은 집적도의 소자에 대한 요구가 커지고 있다. 그러나 소자의 크기가 작아지면서 비례 축소로 인한 게이트 누설 전류, 셀간 간섭, 단 채널 효과 등과 같은 문제들이 발생한다. 이에 따라 제한된 공간에서의 coupling ratio값이 증가해야 하는 문제가 주목 받으면서 얇은 절연층에 대한 많은 연구가 진행되고 있다. 본 연구에서는 절연층 구조를 비대칭으로 사용한 낸드 플래시 메모리의 누설전류의 변화와 coupling ratio값의 변화를 관찰하였다. 비대칭 절연층 구조를 가지는 낸드 플래시 메모리의 전기적 특성을 멀티 오리엔테이션 모델을 포함한 3차원 TCAD 시뮬레이션을 이용하여 계산하였다. 메모리 소자가 각 셀 간의 절연층을 가질 때 낮은 셀 간 간섭과 높은 coupling ratio 값을 가진다. 절연층의 구조 높이와 방향의 두께가 증가 할수록 게이트 누설 전류의 값이 크게 줄어들었다. 또한 비대칭 절연층 구조의 플래시 메모리에서 플로팅 게이트의 on-current 레벨과 전위 값이 기존의 플래시 메모리에 비해 크게 나타나는 시뮬레이션 결과값을 관찰하였다. 비대칭 절연층 구조를 가지는 플래시 메모리는 게이트 누설 전류에 영향을 미치는 절연층 주위의 전기장의 값이 기존 구조에 비해 약 30% 감소하였고 같은 프로그램 동작 전압에서 플로팅 게이트에 주입되는 전하의 양 또한 증가하였다. 이 연구 결과는 낸드 플래시 메모리 소자에서 게이트 누설 전류 문제를 감소시키고 프로그램 특성을 증진시키는데 도움이 된다.

• Journal of the Korean housing association
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• v.16 no.6
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• pp.1-7
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• 2005

도시화는 현대사회의 가장 큰 특징이며 도시가 성장하면서 과거의 기능이 변화하고 도시내부의 공간구조가 점차 기능적으로 분화하는 경향이 있다. 그 중 가장 주목할 만한 것 중의 하나는 주거지역의 입지변화와 공간적 확산과정에서 나타나는 주거지 분화현상이다. 도시생태학자 Hoyt은 주거지 이동패턴에 대하여 도시 내의 주거지분포 패턴을 결정짓는 핵심적인 요인으로 최고지대를 지불할 수 있는 부유층의 주거입지 선택에 따라 전체 도시의 계층별 주거분포가 영향을 받게 된다고 주장하였다. 서울은 소규모로 계획된 역사도시에서 인구 1000만의 대도시로 성장하여 오면서 많은 구조적 변화를 경험하여 현재의 공간구조를 이루게 되었다. 현재 전체 서울의 주택지는 동일한 것이 아니고 각종 주위환경에 따른 성격과 특성을 달리하는 요소로 구성되어 있다. 이 특성을 달리하는 주택지들이 모여서 각기 상이한 역할을 수행하고 서로 기능적 관계를 맺으면서 주택지를 형성하고 있다. 선형이론(Hoyt's Sector theory)에 따르면 고급주택지역의 도시 공간구조에 많은 영향을 미치고 있다고 주장하였다. 그럼에도 불구하고 서울의 고급주택지역의 분포와 그 입지 특성에 관한 연구는 미비한 실정이다. 본 연구의 목적은 서울시 고급주택지역의 분포를 형성하는 원인을 규명하는데 있다. 고급주택지의 지역적 분포를 파악하여 그 입지 성향과 특성을 알게 되면 도시의 토지이용계획, 특히 주거지계획에 도움이 될 수 있다.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.2 no.2
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• pp.94-98
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• 2009

Acupuncture is a treatment method that originated more than 3,000 years ago in China and is practiced in most of the world. Acupuncture became the most popular complementary and alternative medicine modality. Ultrasound is useful for research and educational purposes, visualizing needle insertion at acupuncture points, especially next to vulnerable structures such as nerves or the pleura. Additionally, ultrasound is an ideal imaging method for evaluation the biomechanical effects of needle manipulation on tissue and has the distinctive advantage of yielding both images of tissue morphology and biomechanical information. Elastography take aim at quantifying a mechanical response or the mechanical property of tissues from a mechanical stimulus, generated internally or externally. Therefore, the combination of ultrasound and elastography analyses allows quantitative assessment of dynamic changes in the structure of human connective tissue.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.7
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• pp.605-611
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• 2013

If an accident vehicle propagates emergency messages to other vehicles close to it, the other drivers may realize and avoid the accident spot. In this letter, we propose a broadcast scheme to propagate emergency messages fast in urban VANETs (Vehicular Ad-Hoc Networks) with the help of GPS (Global Position System). In our scheme, a transmitting vehicle chooses the farthest node as the next relay vehicle to propagate emergency messages. And, we suggest an algorithm for intersection recognition and SCF (Store-Carry-Forward) task by taking advantage of periodic hello packets to reduce the propagation time and enhance the delivery ratio.

• 전자공학회논문지 IE
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• v.46 no.2
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• pp.1-6
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• 2009

The inductor needs to have the desire of super miniaturization, substance of high density and no electronic obstacle. In this study, it analyzes electromagnetic field properties of the core due to inserted high current to develop union type inductor. As the results, it appears high electromagnetic field in inductor insides, but magnetic is very small in inductor surfaces. Also, magnetic distribution are almost 0[T] in circumferences get out of the inductor surfaces. It is an evidence that magnetic distribution as the electronic magnetic obstacle does not appear at other electronic parts. These above results affect to develop the union type inductor, especially it can be expect to help analysis of electromagnetic field properties of inductor core and reliability improvement.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.21 no.4
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• pp.366-369
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• 1999

The nasal and zygoma bone are parts of frequently fracturing of facial bones because of anatomically protrusion. Of facial bone fractures, nasal bone is at the high level of incidence rate. But zygoma fracture that anatomical characteristics increase the incidence rate also is occupied considerable part of the facial bone fracture. The outline of face is decided by form of underlying skeletal structure, of that, zygoma plays an important role in. Zygoma is closely attached to surrounding anatomic structure as orbit, maxillary sinus. Aesthetic and functional disturbance are developed by zygoma fracture from trauma, complications, as facial asymmetry, trismus, sensory disturbance, epistaxis, periorbital hemorrhage, diplopia etc, are developed. The patterns of complications following displacement of fractured fragment of zygoma by trauma are slightly different.

• The Journal of the Acoustical Society of Korea
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• v.15 no.4
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• pp.105-112
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• 1996

A linear acoustic analysis for baffled rocket combustion chambers has been developed. This study provides the comprehensive theoretical background for the baffle as one of the stabilizing devices in a liquid rocket propulsion system. Several specific effects of baffles are presented as mechanisms by which baffles eliminate instability. Included are longitudinalization of transverse waves inside baffle compartments, severe restriction of velocity fluctuations near the injector face, and decreased normal mode frequency of the chamber.