• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.222-222
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• 2011

용량성 결합 플라즈마는 반도체 및 디스플레이 공정에서 널리 쓰이기 때문에 그 방전 특성에 관한 연구는 매우 중요하다. 하지만 대부분의 연구는 상대적으로 유사한 면적을 갖는 전극 구조에서 주로 진행되어 왔다. 따라서 본 연구는 두 전극의 면적 차이가 매우 큰 비대칭 구조를 갖는 용량성 결합 플라즈마에서 방전 특성을 측정하였으며, 전력 소비 모드 전이와 플라즈마 밀도와의 상관관계에 관한 연구를 진행하였다. 인가 전력 또는 방전 전류가 증가함에 따라서 플라즈마에 전달된 전력은 초기에는 선형적으로 증가하다가 점차적으로 급격히 증가하였으며, 방전 저항은 감소하다가 증가하는 형태의 전이를 보였다. 전달 전력과 방전 저항의 변화는 용량성 결합 플라즈마에서 초기에는 대부분의 전력이 플라즈마 내의 전자에 의해 소비되다가 점차 쉬스 내의 이온의 가속 에너지로 소비되는 전력 소비 모드 전이에 의한 것이며, 이로 인해 플라즈마 밀도는 처음에는 큰 폭으로 증가하다가 그 증가 폭이 줄어들었다. 이러한 방전 특성에 관한 연구는 다양한 아르곤 압력 범위에서 인가 전력을 증가시킴에 따라서 실험하였으며, 스퍼터, 에칭 등 산업용 플라즈마 공정에서 최적의 방전 조건 형성을 위해 큰 도움이 되리라 예상된다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.2
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• pp.290-296
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• 2020

In this paper, we analyze the effect of mobility on the performance of full-duplex radio. For this, we implement a full-duplex radio prototype using a software-defined radio that is powered by a battery and can thus function in mobile environments. In addition, we compare the performance of self-interference cancellation schemes for two cases considering multi-antenna based full duplex radio and circulator based full duplex radio, respectively. Finally, we show a negative effect of mobility on the self-interference cancellation performance of the full-duplex radio system, and analyze the effect of the update period of the self-interference cancellation filter on the performance. In particular, when the update period is reduced by about 1000 times, the power of self-interference is reduced by 5.7dB for circulator-based full-duplex radio and 3.1dB for both antenna-based full-duplex radio.

• Journal of Chest Surgery
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• v.40 no.11
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• pp.789-792
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• 2007

We report here a case of pulmonary benign metastasizing leiomyoma from the uterus in a 45 year old woman. The patient presented for investigation of multiple pulmonary nodules on a routine chest roentgenogram. The patient had undergone uterine myomectomy due to uterine leiomyoma 10 years earlier. We performed thoracoscopic wedge resection for definitive diagnosis. Histologically, spindle shaped smooth muscle cells appeared between collagen stroma, histology similar to that seen in uterine myoma. The tumor tissue tested positive for estrogen and progesterone receptors. The pathological findings were consistent with benign metastasizing leiomyoma. The patient was in pre-menopause. She received no specific treatment for lung tumors, and we did not found any changes in the lesions after one year follow up without any medication.

• Journal of Chest Surgery
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• v.32 no.1
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• pp.27-31
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• 1999

Background: In spite of the development of chemotherapy, prognosis of metastatic lung cancer was poor. On the other hand, surgical intervention has proven itself to bring out superior results, therefore more operations are being praticed based on this superiority against chemotherapy and other modalities on metastatic lung cancer. Material and Method : We analyzed the surgical cases performed from 1983 to 1997 on 17 cases and estimated 5 year survival rate using Kaplan-Meier method. Result: Average age was 42.8, ratio between male and female was 10:7. We had 8 single lobe resections,3 pneumonectomies,1 wedge resection,2 bilobectomy and 3 cases of lobar resection with wedge resection. 5 deaths have occured and among the 5, 3 patients were caused by recurrence of ca. The remaining 12 patients are being followed up in OPD basis among these, 3 recurrence were observed and 9 are still free of cancer. The average survival time was 40.5 months and 5 year survival rate obtained through the Kaplan-Meier method was 60.4%. Conclusion: Even though we are a bit short of cases, we recommend that a thoracic surgeon approach this disease through a surgical method as possibly as he could.

• Radiation Oncology Journal
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• v.16 no.2
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• pp.177-184
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• 1998

Purpose : Radiotherapy has been the mainstay of the treatment of brain metastases. We evaluated the response rate, survival and prognostic factors of patients with brain metastases treated with radiotherapy for palliative purpose. Materials and Methods : From January 1994 through April 1997, in all 42 patients, a retrospective analysis was undertaken. Of these, 33 patients received whole brain irradiation with 30Gy in 10 daily fractions with or without a boost of 10Gy in 5 daily fractions to the site of solitary lesion. Nine patients failed to complete the planned treatment Results : Of 33 patients who finished radiotherapy, complete and partial response were observed in $4(12\%)$ patients and $22(67\%)$ ones, respectively. Overall response rate was $79\%$ and median survival was 4 months. In univariate analysis, prognostic factors affecting survival were initial neurologic function class(p=0.0136), extracranial tumor activity(p=0.042), and response after radiotherapy(p=0.001). Conclusion : We confirmed that whole brain irradiation is the effective means for treating the patient with brain metastases. initial neurologic function class, extracranial tumor activity, and response alter radiotherapy were identified as prognostic factors affecting survival.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.33 no.2
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• pp.103-111
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• 2020

Recently, the use of transfer slab system has increased greatly. However, several construction problems are being encountered owing to its excessive thickness. Therefore, in this study, a transfer slab system that uses a reverse drop panel, which can utilize the facility space of the pit floor by reducing the transfer slab thickness, was considered. To investigate the shear behavior of transfer slab system that uses the reverse drop panel, the two-way shear strength of transfer slab-column connection with the reverse drop panel was analyzed using nonlinear FE analysis. In addition, the two-way shear strength evaluations of transfer slab with the reverse drop panel conducted using the existing evaluation methods were verified by comparing the strengths predicted by those methods with the results of nonlinear FE analysis.

• Journal of Korea Game Society
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• v.19 no.6
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• pp.37-48
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• 2019

This paper aims to clarify the game performance and its principle and operation method at the depth of successful content through gameness transition, which is one of the transmedia phenomena of games. This paper investigated the current state of gameness transition and analyzed the game structure and working principle by using Chris Crawford's creative expression taxonomy model. As a result, the types of gameness transition could be extracted into space exploration type, stage type, reasoning competition type, and mutual competition type.

• Journal of the Earthquake Engineering Society of Korea
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• v.6 no.3
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• pp.23-29
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• 2002

A wall-frame type structural system has been widely used to make full use of a limited land in large cities to satisfy the several functional requirement in one building. However, this type of hybrid structure brought some problems due to the vertical discontinuity of a structural system. The response of a wall-frame type structural system having a deep transfer girder was observed. An arch system was introduced to replace the deep transfer girder. The adequacy of an arch system was observed for the various boundary conditions of a system. The proposed system was compared to a general transfer girder system by applying both gravity load and lateral load. It was observed that an arch system fairly distributes the stress without concentrating stress at a certain location of a system differently from the current transfer girder system. The moment decrement effect of a column can also be obtained by eliminating the large mass of a transfer girder. Also it was investigated that an arch system is more economical and effective than the current transfer girder system.

• Radiation Oncology Journal
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• v.27 no.3
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• pp.163-168
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• 2009

Purpose: This study was a retrospective evaluation of the efficacy of stereotactic radiosurgery (SRS) in patients with >4 metastases to the brain. Materials and Methods: Between January 2004 and December 2006, 68 patients with $\geq$4 multiple brain metastases were included and reviewed retrospectively. Twenty-nine patients received SRS and 39 patients received whole brain radiotherapy (WBRT). Patients with small cell lung cancers and melanomas were excluded. The primary lesions were non-small cell lung cancer (69.0%) and breast cancer (13.8%) in the SRS group and non-small cell lung cancer (64.1%), breast cancer (15.4%), colorectal cancer (12.8%), esophageal cancer (5.1%) in the WBRT group. SRS involved gamma-knife radiosurgery and delivered 10~20 Gy (median, 16 Gy) in a single fraction with a 50% marginal dose. WBRT was delivered daily in 3 Gy fractions, for a total of 30 Gy. After completion of treatment, a follow-up brain MRI or a contrast-enhanced brain CT was reviewed. The overall survival and intracranial progression-free survival were compared in each group. Results: The median follow-up period was 5 months (range, 2~19 months) in the SRS group and 6 months (range, 4~23 months) in the WBRT group. The mean number of metastatic lesions in the SRS and WBRT groups was 6 and 5, respectively. The intracranial progression-free survival and overall survival in the SRS group was 5.1 and 5.6 months, respectively, in comparison to 6.1 and 7.2 months, respectively, in the WBRT group. Conclusion: SRS was less effective than WBRT in the treatment of patients with >4 metastases to the brain.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.263-263
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• 2010

실제 옷처럼 입는 컴퓨터를 구현하거나 복잡하고 움직임이 많은 사람의 장기 등 생체에 이식 가능한 정보 전자 소자를 개발하려는 시도가 많이 이루어지고 있다. 현재는 기존의 반도체 공정과 실리콘 소재를 기반으로 연구 결과가 보고되고 있는데, 이는 소자 제작에 있어서 높은 공정 온도 등으로 인해 응용성이 제한되는 상황이다. 우리는 metal oxide 나노선과 단일벽 탄소나노튜브 (SWCNT)를 성장하여 각각 슬라이딩 전이법과 thermal tape 전이법을 이용하여 원하는 기판에 전이하고 소자를 제작하였다. metal oxide 나노선은 슬라이딩 전이를 통해 정렬된 상태로 패턴을 제작하였으며, SWCNT는 density 제어와 채널 크기 조정을 통해 반도체성 채널을 유도하여 소자 특성을 확보하였다. 또한 각 나노선의 전계효과소자와 SWCNT로 구성된 PMOS inverter를 유연한 고분자 필름기판위에 구현하고, 이를 스트레칭이 가능한 스테이지를 이용해 strain 대비 전기특성 변화를 분석하였다. 유연성이 좋은 나노선/나노튜브로 제작된 해당 소자는 전체 소자가 스트레칭이 가능할 수 있게 연결구조를 디자인하여 수십% 의 stain에도 각각의 전기특성이 유지되었다. 이처럼 스트레칭이 가능한 1차원 나노소재 소자는 그 유연성을 바탕으로 입는 옷처럼 구겨지거나 늘여지게 되는 다양한 스트레칭 상황에도 특성이 보장되어 미래 정보전자소자로 많은 응용이 가능할 것으로 예상된다.