• Journal of Gastric Cancer
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• 제1권1호
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• pp.24-31
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• 2001

Purpose: Despite knowledge of the adverse effects of resection-line disease, surgeons continue to perform inadequate resections. This demonstrates the need for a more aggressive approach to assessment of resection margins at operation. Materials and Methods: Seven hundred fifteen gastric cancer patients who were operated on at our hospital from 1992 to 1998 were included in this analysis. Various clinicopathological factors, including resection-line involvement, were ascertained from the surgical and histopathological records. Results: Of the 715 evaluable patients, 27 patients ($3.8\%$) had involvement of one or both resection lines; in 10 patients the proximal resection line only, in 16 the distal resection line only, and 1 both resection lines were involved. Presence of resection-line involvement was significantly associated with T3 and T4 stage, N (+) stage, M (+) stage, type of operation (total gastrectomy), tumor location (entire stomach), size$\geq$11 cm), and gross type of tumor (Borrmann 4 type). When performing a distal subtotal gastrectomy, no involvement was found when the cranial and caudal distances between the lesion and the line of transection was equal to or greater than 2 cm and 3 cm, respectively, for early cancer and 7 cm and 3 cm, respectively, for advanced cancer. When performing a total gastrectomy for upper 1/3 or middle 1/3 gastric cancer, no involvement was found when the cranial distances between the lesion and the line of transection were equal to or greater than 3 cm and 4 cm, respectively, without distinction of the presence of serosal invasion. Conclusions: The difference in survival between positive and negative margin patients is limited to the group of patients with curative surgery. An important principle of treatment is that the entire tumor must be removed with a 3 cm distal margin and a 2- to 7 cm margin depending on the location and the depth of wall invasion of the tumor, to provide histologically negative margins.

• 방사성폐기물학회지
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• 제12권4호
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• pp.299-314
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• 2014

인양장비는 원자력발전소에서 발생하는 사용후핵연료를 운반하는 운반용기를 인양하기 위해 사용된다. 본 연구는 원자력 안전위원회고시 제2013-27호와 미국 10CFR Part 71 ${\S}71.45$에서 규정하는 기술수준에 따라 이론적인 방법과 유한요소방법으로 인양장비의 구조적안전성을 평가하였다. 이론적으로 평가한 결과 모든 구성 요소에서의 응력이 응력제한치 내에 있어 운영상 발생하는 구조적 안전성을 확보하고 있는 것으로 판단하였다. 또한 유한요소해석을 통한 평가결과, 항복과 극한조건 모두에서 설계기준을 만족하는 것으로 평가되었다. 모든 구성요소에서 충분한 안전여유도(항복조건에서 3 이상의 안전율, 극한조건에서 5 이상의 안전율)를 갖는 것으로 나타나 구조적으로 안전하다고 판단하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제17권9호
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• pp.4327-4333
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• 2016

Purpose: To systematically review efficacyand safety of robotic gastrectomy (RG) compared with conventional laparoscopic gastrectomy (LG) for gastric carcinoma. Materials and Methods: A systematic literature search was carried out using PubMed, Cochrane Library, CBM, CNKI, WanFang, VIP and other sources like relevant references to obtain comparative studies assessing the effectiveness and safety between RG and LG published between 2013 and 2016. Then the literature was screened and the data were extracted by 2 independent reviewers. The quality of the literature was assessed, and the data analyzed using Stata/SE 14 software. Fixed effects or random effects models wereapplied according to heterogeneity. Results: A total of 12 non-randomized observational clinical studies involving 3,580 patients were included, of which 1,096 had undergone RG and 2,484 had received LG. The results of the meta-analysis showed in terms of effectiveness, RG was associated with less blood loss, less time to first flatus and greater number of harvested lymph nodes, but there were no significant differences in proximal and distal resection margins, compared with LG. In terms of efficiency, RG was associated with shorter hospital stay, but longer operative time. In terms of safety, there were no statistically significant differences in complications, mortality and conversions between RG and LG. Conclusions: RG can achieve comparable or better short-term and radical effects than LG, with respect to effectiveness, efficiency and safety in treatment of gastric carcinoma. Future studies involving RG should focus on decreasing operative time and reducing cost. Moreover, there is a need for randomized controlled trials comparing the two techniques with long-term follow-up.

• 항공우주시스템공학회지
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• 제16권6호
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• pp.106-113
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• 2022

본 연구에서는 eVTOL 개인항공기의 개별 블레이드 피치 제어용 선형 구동기 기본설계 모델에 대한 구조 안전성을 검토하였다. Stall 하중에 대한 정적 구조 안전성을 검토하기 위해 유한요소법을 이용한 응력해석을 수행하여 안전여유율을 계산하였다. 또한 선형 구동기의 운용조건에 대한 피로수명을 평가하기 위해 피로 해석을 수행하였다. 다물체 동역학 분석을 통해 블레이드 피치각에 따른 하중이력을 산출하였다. 또한 정하중 해석에 정격하중을 적용하여 응력 분포를 산출하고 피로 해석에 활용하였다. 해석 결과, 선형 구동기의 모든 부품은 0 이상의 안전여유율이 계산되었고, 10⁷ cycles 이상의 피로수명이 산출되어 구조적으로 안전함이 확인되었다.

• 항공우주기술
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• 제3권2호
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• pp.72-80
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• 2004

터보펌프를 구성하는 부분 조합체 중의 하나인 산화제 펌프의 인듀서와 임펠러에 대해서 정적 구조해석을 수행하였다. 먼저 온도, 원심력 및 압력의 영향을 각각 독립적으로 파악한 후 조합된 하중이 작용하는 경우에 대해서 인듀서와 임펠러의 거동을 살펴보았다. 설계된 형상과 재질에 대해서 구조적으로 가장 큰 영향을 미치는 요소는 온도였으며, 모든 경우에 대해서 적절한 안전 여유를 갖는 것으로 예측되었다. 하지만 진동의 영향은 고려되지 않았기 때문에 회전부와 케이싱과의 간섭 여부를 정확히 파악하기 위해서는 추가적으로 진동 해석이 수행되어야 할 것이다.

• 대한기계학회논문집
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• 제11권2호
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• pp.205-213
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• 1987

본 논문에서는 비압축 선형 점탄성재료를 원통체로 모델화하여 열하중에 대한 거동을 점유적 시간증분과정을 적용하여 수치해를 제시하고 원통체를 제작실험하여 변 형과 비파괴검사를 통해 측정하여 비교검토하였다. 또한 이론적 수치해와 시편과의 안전율을 각 파괴기준(failure criteria)에 적용하여 비파괴검사결과와 비교하였다.

• 대한두개안면성형외과학회지
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• 제25권2호
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• pp.90-94
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• 2024

Primary cutaneous mucinous carcinoma (PCMC) is a rare malignancy of the sweat glands that most commonly affects the periorbital area. It is characterized by slow growth over a prolonged period, and its morphology can be easily confused with a benign tumor, such as an epidermal cyst. Consequently, many patients experience recurrence after undergoing multiple resections. However, there are few reports concerning the surgical management of PCMC. We present two cases of PCMC originating in the periorbital area. The first case involved a 76-year-old man with a mass measuring 3.0×1.5 cm that had been increasing in size. The second case was a 61-year-old man with two masses, each measuring 1.0×1.0 cm, that were also growing. Both patients underwent wide excision with a 5-mm safety margin, which was determined based on the widest view of the cross-section of the mass on the magnetic resonance imaging. Subsequently, based on the intraoperative frozen biopsy results, both patients underwent additional excision with a 5-mm safety margin in only one direction. This report shows that, when determining the surgical margin of PCMC in periorbital area, employing imaging modalities and intraoperative frozen biopsies can be helpful for narrowing the surgical margin.

• Nuclear Engineering and Technology
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• 제46권3호
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• pp.299-312
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• 2014

An uncertainty propagation methodology based on the Monte Carlo method is applied to PWR nuclear design analysis to assess the impact of nuclear data uncertainties. The importance of the nuclear data uncertainties for $^{235,238}U$, $^{239}Pu$, and the thermal scattering library for hydrogen in water is analyzed. This uncertainty analysis is compared with the design and acceptance criteria to assure the adequacy of bounding estimates in safety margins.

• 대한후두음성언어의학회지
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• 제28권2호
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• pp.128-130
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• 2017

Sarcomatoid carcinomas are biphasic tumors which have surface epithelial changes and an underlying spindle-shaped neoplastic proliferation. A 62-year-old male with hoarseness came to our hospital for evaluation. A single smooth polypoid lesion was detected on his right true vocal fold by larnygoscope. The patient was diagnosed with vocal polyp and treated with surgical excision. Pathology report of the excised specimen was compatible with sarcomatoid carcinoma. Therefore, further surgical resection was performed to secure safety margins. We report a case of a sarcomatoid carcinoma patient who was clinically diagnosed as vocal polyp.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 B
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• pp.600-602
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• 1997

The kalman filter which has good estimating capabilities by means of the recursive computation from the previously known of obtained data is usually used for the system estimation in the case of not being directly measurable. The best estimating technique is still open issues on the PWR reactor control system to increase operating contingencies and to predict the safety margins for safer reactor operation. This paper addressed its estimating technique using kalman filter for the more flexible reactor control and showed the reasonable approach for discretization of the continuos-time system for reduction of computation errors.