• 한국추진공학회:학술대회논문집
• /
• 한국추진공학회 2011년도 제37회 추계학술대회논문집
• /
• pp.772-776
• /
• 2011

개발 중인 중형 전기추진 무인기는 전력원으로 태양전지, 연료전지, 이차전지를 사용한다. 전력변환기 및 컨버터를 없이 전압 매칭을 통해 전력원을 선정하고 단품시험을 수행하였다. 여러 종류의 전력원을 통합하여 사용함에 따른 각 전력원 별 특성파악 및 에너지 사용 비율을 정량적으로 평가하기 위해 5시간 지상통합시험을 수행하였다. 그 결과 배터리는 시동 및 과도상태에서 다른 동력원에 비해 빠른 출력반응을 보였으며, 연료전지와 태양전지는 순항영역에서 주 전력 공급원의 역할을 수행함을 확인하였다. 사용한 에너지 비율은 연료전지, 태양전지, 배터리가 각각 68%, 29%, 2.5%임을 알 수 있었다.

• Journal of Gastric Cancer
• /
• 제20권2호
• /
• pp.152-164
• /
• 2020

Purpose: To compare long-term disease-free survival (DFS) between patients receiving tegafur/gimeracil/oteracil (S-1) or capecitabine plus oxaliplatin (CAPOX) adjuvant chemotherapy (AC) for gastric cancer (GC). Materials and Methods: This retrospective multicenter observational study enrolled 983 patients who underwent curative gastrectomy with consecutive AC with S-1 or CAPOX for stage II or III GC at 27 hospitals in Korea between February 2012 and December 2013. We conducted propensity score matching to reduce selection bias. Long-term oncologic outcomes, including DFS rate over 5 years (over-5yr DFS), were analyzed postoperatively. Results: The median and longest follow-up period were 59.0 and 87.6 months, respectively. DFS rate did not differ between patients who received S-1 and CAPOX for pathologic stage II (P=0.677) and stage III (P=0.899) GC. Moreover, hazard ratio (HR) for recurrence did not differ significantly between S-1 and CAPOX (reference) in stage II (HR, 1.846; 95% confidence interval [CI], 0.693-4.919; P=0.220) and stage III (HR, 0.942; 95% CI, 0.664-1.337; P=0.738) GC. After adjustment for significance in multivariate analysis, pT (4 vs. 1) (HR, 11.667; 95% CI, 1.595-85.351; P=0.016), pN stage (0 vs. 3) (HR, 2.788; 95% CI, 1.502-5.174; P=0.001), and completion of planned chemotherapy (HR, 2.213; 95% CI, 1.618-3.028; P<0.001) were determined as independent prognostic factors for DFS. Conclusions: S-1 and CAPOX AC regimens did not show significant difference in over-5yr DFS after curative gastrectomy in patients with stage II or III GC. The pT, pN stage, and completion of planned chemotherapy were prognostic factors for GC recurrence.

• Journal of Preventive Medicine and Public Health
• /
• 제50권6호
• /
• pp.401-410
• /
• 2017

Objectives: The purpose of this study was to examine the associations of childbirth, breastfeeding, and their interaction with breast cancer (BC) risk reduction, and to evaluate the heterogeneity in the BC risk reduction effects of these factors by menopause, hormone receptor (HR) status, and pathological subtype. Methods: BC patients aged 40+ from the Korean Breast Cancer Registry in 2004-2012 and controls from the Health Examinee cohort participants were included in this study after 1:1 matching (12 889 pairs) by age and enrollment year. BC risk according to childbirth, breast-feeding, and their interaction was calculated in logistic regression models using odds ratios (ORs) and 95% confidence intervals (CIs). Results: BC risk decreased with childbirth (3+ childbirths relative to 1 childbirth: OR, 0.66; 95% CI, 0.56 to 0.78 and OR, 0.80; 95% CI, 0.68 to 0.95 in postmenopausal and premenopausal women, respectively); and the degree of risk reduction by the number of children was heterogeneous according to menopausal status (p-heterogeneity=0.04), HR status (p-heterogeneity<0.001), and pathological subtype (p-heterogeneity<0.001); whereas breastfeeding for 1-12 months showed a heterogeneous association with BC risk according to menopausal status, with risk reduction only in premenopausal women (p-heterogeneity<0.05). The combination of 2 more childbirths and breastfeeding for ${\geq}13$ months had a much stronger BC risk reduction of 49% (OR, 0.51; 95% CI, 0.45 to 0.58). Conclusions: This study suggests that the combination of longer breastfeeding and more childbirths reduces BC risk more strongly, and that women who experience both 2 or more childbirths and breastfeed for ${\geq}13$ months can reduce their BC risk by about 50%.

• Journal of Preventive Medicine and Public Health
• /
• 제34권3호
• /
• pp.253-261
• /
• 2001

Objectives : To evaluate the hypothesis that air pollution could increase emergency room visits for respiratory diseases, and if so, to quantify the strength of association between those. Methods : We compiled daily records of hospital emergency room visits for respiratory diseases in Seoul, from November 1. 1955 to October 31. 1996, by using medical utilization data of unscheduled visits. In addition, air quality and weather data for the same period was collected. And a case-crossover design was applied by adopting conditional logistic regression analysis to determine the relationship between air pollutants and emergency room visits for respiratory diseases. In particular, the control periods were chosen by a bidirectional paired matching technique 7, 14, and 21 days before and after the case periods. Results : Only ozone was associated with the increased number of emergency room visits for respiratory diseases. The relative risk according to a 30ppb increase of ozone concentration (24hr mean, lagged 1day) was 1.91(95% confidence interval = 1.78-2.05). Conclusion : There was a statistically significant association between the ambient ozone and daily emergency room visits for respiratory diseases.

• Asian Pacific Journal of Cancer Prevention
• /
• 제15권24호
• /
• pp.10773-10777
• /
• 2015

Background: Treatment for breast cancer is mainly performed by surgical resection of primary tumors and chemotherapy. However, after tumor invasion and metastases, breast cancer is hard to control. Clarification of the pathogenic mechanisms would be helpful to the prognosis or therapy for the breast cancer. The aim of this study is to investigate the clinical and prognostic implications of legumain protein Materials and Methods: In this study, we examined mastectomy specimens from 114 breast cancer and matching, 26 adjacent non-cancerous tissues using immunohistochemistry. Results: The results indicated that positive expression of legumain protein in breast cancer was 51.8 % (59/114) and the positive expression of legumain protein in adjacent non-cancerous tissue was 11.5% (3/26). It appeared to be related with lymph node metastasis of breast cancer (p=0.02) and correlation analysis indicated that legumain expression was correlated positively with the estrogen receptor (ER) and mutant-type p53 expression (both p<0.05). Positive legumain expression was significantly associated with shorter overall survival time in breast cancer patients (log-rank p<0.01). Multivariate survival analysis suggested that the positive legumain expression was an independent predictor of poorer overall survival in patients with breast cancer (HR=0.24; 95%CI 0.11-0.65, p=0.03). Conclusions: Legumain might be a new potential biomarker for breast cancer, which may reflect the prognosis and overall survival.

• The Korean Journal of Pain
• /
• 제32권3호
• /
• pp.206-214
• /
• 2019

Background: Although case reports have suggested that the erector spinae plane block (ESPB) may help analgesia for patients after breast surgery, no study to date has assessed its effectiveness. This retrospective observational study analyzed the analgesic effects of the ESPB after total mastectomy. Methods: Forty-eight patients were divided into an ESPB group (n = 20) and a control group (n = 28). Twenty patients in the control group were selected by their propensity score matching the twenty patients in the ESPB group. Patients in the ESPB group were injected with 30 mL 0.375% ropivacaine, followed by catheter insertion for further injections of local anesthetics every 12 hours. Primarily, total fentanyl consumption was compared between the two groups during the first 24 hours postoperatively. Secondary outcomes included pain intensity levels (visual analogue scale) and incidence of postoperative nausea and vomiting (PONV). Results: Median cumulative fentanyl consumption during the first 24 hours was significantly lower in the ESPB ($33.0{\mu}g$; interquartile range [IQR], $27.0-69.5{\mu}g$) than in the control group ($92.8{\mu}g$; IQR, $40.0-155.0{\mu}g$) (P = 0.004). Pain level in the early postoperative stage (<3 hr) and incidence of PONV (0% vs. 55%) were also significantly lower in the ESPB group compared to the control (P = 0.001). Conclusions: Intermittent ESPB after total mastectomy reduces fentanyl consumption and early postoperative pain. ESPB is a good option for multimodal analgesia after breast surgery.

• 기술혁신학회지
• /
• 제10권1호
• /
• pp.22-46
• /
• 2007

본 논문은 SW인력수급의 질적, 양적 불일치를 해소하고 산학협력을 기반으로 하는 인력양성을 위해 공급망관리(Supply Chain Management) 모델에 대한 개념을 SW인력정책에 적용하였다. 대학을 공급자로 기업을 수요자로 인식하고, 대학과 기업간의 산학협업을 통해 수요지향적 SW인력 양성 시스템을 구축하는 최적의 공급망 관리로 새롭게 접근하였다. 산업체 수요를 반영하기 위해 SW분야 산학연관 전문가로 구성된 인력양성정책협의회를 통해 인력수요계획을 수립하고, 이를 대학 내 수요 지향적 교과목개발 및 교과과정개편에 반영하여 전공역량이 강화되는 공학인증으로 유도하였다. 또한 산학협력 프로젝트 수행을 통해 취업으로 이루어져 산업체가 필요한 인력을 배출하는 수급매칭 프로세스인 인력양성 SCM모델의 가치사슬(Value Chain)을 제시하였다.