• Journal of Information Processing Systems
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• 제10권2호
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• pp.314-333
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• 2014

When analyzing default predictions in real estate companies, the number of non-defaulted cases always greatly exceeds the defaulted ones, which creates the two-class imbalance problem. This lowers the ability of prediction models to distinguish the default sample. In order to avoid this sample selection bias and to improve the prediction model, this paper applies a minority sample generation approach to create new minority samples. The logistic regression, support vector machine (SVM) classification, and neural network (NN) classification use an imbalanced dataset. They were used as benchmarks with a single prediction model that used a balanced dataset corrected by the minority samples generation approach. Instead of using prediction-oriented tests and the overall accuracy, the true positive rate (TPR), the true negative rate (TNR), G-mean, and F-score are used to measure the performance of default prediction models for imbalanced dataset. In this paper, we describe an empirical experiment that used a sampling of 14 default and 315 non-default listed real estate companies in China and report that most results using single prediction models with a balanced dataset generated better results than an imbalanced dataset.

• Current Photovoltaic Research
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• 제2권2호
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• pp.59-62
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• 2014

Minority carrier diffusion length is one of the most important parameters of solar cells, especially for short circuit current density (Jsc). In this report, we proposed the calculating method of the minority carrier diffusion length ($L_n$) in CIGS solar cells through biased quantum efficiency (QE). To verify this method's reliability, we chose two CIGS samples which have different grain size and calculated $L_n$ for each sample. First of all, we calculated out that $L_n$ was 56nm and 97nm for small and large grain sized-cell through this method, respectively. Second, we found out the large grain sized-cell has about 7 times lower defect density than the small grain sized-cell using drive level capacitance profiling (DLCP) method. Consequently, we confirmed that $L_n$ was mainly affected by the micro-structure and defect density of CIGS layer, and could explain the cause of Jsc difference between two samples having same band gap.

• 대한한방내과학회지
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• 제39권5호
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• pp.1068-1074
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• 2018

Objectives: Acute bronchitis is a common inflammatory disease with symptoms related to temporary inflammation of the airways. It is caused by a viral infections in over 95% of cases. A small minority of cases are caused by bacteria; however, there is little evidence that antibiotics are effective in the treatment of the condition. This report is a case of administering Dojukgangki-tang to three patients with acute bronchitis. Methods: Patients diagnosed with acute bronchitis were treated with Dojukgangki-tang, and the effects were studied using the bronchitis severity scale (BSS) and acute bronchitis severity scale (ABBS). Results: After treatment with Dojukgangki-tang for 2 weeks, average BSS score changed from $11.33{\pm}2.08$ to $1.67{\pm}1.15$. Average ABSS score decreased from $9.00{\pm}3.00$ to $2.00{\pm}1.00$. Conclusions: This study suggests that Dojukgangki-tang is effective in relieving coughs and sputum related to acute bronchitis.

• Journal of Preventive Medicine and Public Health
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• 제46권2호
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• pp.105-110
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• 2013

Objectives: The mass media play a crucial role in risk communication regarding climate change. The aim of this study was to investigate the trend in journalistic reports on climate change in the daily newspapers of Korea. Methods: We selected 9 daily newspapers in Korea, which according to the ABC Association, represented 77% of newspaper circulation, out of a total of 44 Korean daily newspapers. The collected articles were from 2009 to 2011. All of the articles were sorted into the following 8 categories: greenhouse gas, climate change conventions, sea level rise, Intergovernmental Panel on Climate Change synthesis reports, expected damage and effect, use of fossil fuels, global warming, and mitigation or adaptation. A chi-squared test was done on the articles, which were counted and classified into cause, effect, and measurement of climate change according to the newspaper's majority or minority ownership structure. Results: From the 9 selected newspapers, the number of articles on climate change by month was greatest in December 2009. Generally, the articles vague about climate change (lack of precise data, negative or skeptical tone, and improper use of terminology) were much more common than the articles presenting accurate knowledge. A statistical difference was found based on ownership structure: the majority-owned newspapers addressed the cause of climate change, while the minority-owned newspapers referred more to climate change measurement. Conclusions: Our investigation revealed that generally Korean daily newspapers did not deliver accurate information about climate change. The coverage of the newspapers showed significant differences according to the ownership structure.

• 한국생활과학회지
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• 제9권1호
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• pp.1-12
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• 2000

이 프로젝트는 미국의 소수민족학생들의 과학과 수학의 수행능력과 흥미를 갖도록 혁신적인 교육전략을 개발하기 위한 준 실험설계연구이다. 연구대상은 중학교 7학년과 8학년 학생으로, 과학과 수학에 흥미가 있고 성적이 우수하며, 신체적으로나 기능적으로 장애가 있고, 소수민족이고, 경제적으로 빈곤한 계층이며 여학생을 우선조건으로 실험집단 52명, 비교집단 28명이 무선표집되었다. 연구대상 대부분(72명)이 흑인이고, 나머지(8명)는 히스파니아인이다. 연구내용은 1) 방과후 학술활동 2) 사회적 기술활동 3) 현장학습 4) 가족지원 프로그램을 실험집단에 실시한 후 실험집단과 비교집단의 학업성취도와 실험집단의 자아개념과 프로젝트 활동에 대한 평가를 분석한 것이며, 다음과 같은 연구결과를 얻었다. 1. 학업성취에 있어서 실험집단의 과학성적(CRT)이 통계적으로 비교집단보다 유의한 증가를 보였고, 프로젝트의 목표를 초과달성하였다. 비교집단도 자연적 성숙효과로 증가를 보였으나 유의도는 실험집단보다 낮았다. 2. 학생들의 프로젝트에 대한 평가는 긍정적이었다. 프로젝트 목적과 명확성, 현장학습의 적절성, 게임이나 학술활동보다 현장학습의 선호, 특히 자아존중감 활동이 많은 도움이 되었다고 보고하였다. 3. 실험집단의 자아개념은 프로젝트 기간동안 통계적으로 유의한 증가를 보였으나 학업 성취와의 상관관계는 유의하지 않았다. 이상의 연구결과를 토대로 이 프로젝트의 한국적 상황의 적용에 대한 시사점을 얻을 수 있었다.

• Journal of Preventive Medicine and Public Health
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• 제54권3호
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• pp.161-165
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• 2021

Objectives: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spreads heterogeneously, disproportionately impacting poor and minority communities. The relationship between poverty and race is complex, with a diverse set of structural and systemic factors driving higher rates of poverty among minority populations. The factors that specifically contribute to the disproportionate rates of SARS-CoV-2 infection, however, are not clearly understood. Methods: We evaluated SARS-CoV-2 test results from community-based testing sites in Los Angeles, California, between June and December, 2020. We used tester zip code data to link those results with United States Census report data on average annual household income, rates of healthcare coverage, and employment status by zip code. Results: We analyzed 2 141 127 SARS-CoV-2 test results, of which 245 154 (11.4%) were positive. Multivariable modeling showed a higher likelihood of SARS-CoV-2 test positivity among Hispanic communities than among other races. We found an increased risk for SARS-CoV-2 positivity among individuals from zip codes with an average annual household income

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2015년도 춘계학술대회
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• pp.335-337
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• 2015

사고 준사고 선박의 경우 하인리히 법칙에 의거 사고 전 잠재적 요인을 내재하고 있는 선박이 그 예후를 미리 보이는 경우가 많다. 이러한 잠재적 요인의 집계 및 통계를 통해 사고 유발 가능선박을 분리하고, 이 선박들에 한해서는 기존의 사고 후 대책 마련 방식에서 벗어나 대형 사고를 예방하기 위한 방식으로 접근하는 것이 철저하게 필요하다고 본다. 그리하여 동해 VTS 관제 구역 내 사고 유발 가능 선박에 나타났던 잠재적 요인의 예시들과, 기존 접근 방법의 한계점에 대해 논하고, 분리된 선박에 대해 어떠한 식으로 관리할 것인지 논해보고자 한다.

• Journal of Chest Surgery
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• 제16권3호
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• pp.322-330
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• 1983

TAPVC represents 1 to 4% of all congenital cardiac defects. Generally severe and refractory cardiac failure develops in the majority of patients in the early infancy. In a small minority of patient, they are relatively asymptomatic in infancy, but symptoms will develop of necessity In the later life. Our three cases had dyspnea on exertion and cyanosis and had a history of frequent respiratory infections. All 3 cases had the typical showman configuration on roentgenograms of the chest. Current surgical therapy has greatly altered the unfavorable course of these patients after institution of extra-corporeal circulation. We have experienced three cases from June, 1973 to May, 1983, the patients were undergone complete repair with extracorporeal circulation at the Department of Thoracic and Cardiovascular Surgery in the Yonsei University. The ages ranged from 12 years to 14 years, all cases were supracardiac type of TAPVC. Only one case died due to bleeding from anastomosis site between LA and pulmonary venous trunk. In the remaining two patients with complete corrections of TAPVC, there was excellent relief of symptoms such as dyspnea and cyanosis. Their postoperative course have been good during follow-up.

• 미생물학회지
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• 제44권2호
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• pp.85-92
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• 2008

Pseudomonas aeruginosa는 기회 감염성 병원균으로, Cystic fibrosis, 미생물 감염성 각막염,화상 부위 2차 감염 등의 다양한 질병을 초래한다. 정족수 인식(쿼럼 센싱)이라고도 알려져 있는 세포간 신호전달 기전이 이러한 감염에서 중요한 역할을 하기 때문에 P. aeruginosa의 정족수 인식 시스템들이 집중적으로 연구되어 왔다. P. aeruginosa의 정족수 인식 시스템들을 소개하는 많은 문헌들이 주로 두 개의 주요 acyl-homoserine lactone (AHL) 계열 정족수 신호물질들인 N-3-oxododecanoyl homoserine lactone (3OC12)과 N-butanoyl homoserine lactone (C4)에 초점을 맞추어 설명하고 있지만, 실제로는 몇 가지 새로운 신호물질들이 발견되어져 왔고, 그들이 P. aeruginosa의 병독성과 신호전달에 중요한 역할을 할 수 있음이 제안되어져 왔다. 그 중 하나가 PQS(Pseudomonas quinolone signal; 2-heptyl-3-hydroxy-4-quinolone)인데, 이 물질은 현재 P. aeruginosa의 잘 규명된 주요 신호물질로 인식되고 있다. 이에 더하여, 최근의 연구들은 또 다른 가능성 있는 P. aeruginosa신호물질들을 제안해 왔는데, diketopiperazines (DKPs)과 pyocyanin이 그들이다. DKPs는 환형 dipeptide로써 이를 구성하는 아미노산의 종류에 따라 다양한 구조를 가진다. P. aeruginosa의 배양액에서 검출된 몇몇 DKPs들이 기존에는 AHL에만 특이적으로 반응한다고 알려졌던 Vibrio 랸�N갸 LuxR biosensor를 활성화 시킬 수 있다는 것이 발견되어 새로운 신호물질로 제안되었다. Pyocyanin (1-hydroxy-5-methyl-phenazine)은 P. aeruginosa가 생산하는 여러 phenazine 화합물들 중의 하나로써, 특징적인 청록색을 띄는 산화-환원 활성물질이다. 이 물질도 정체 성장기 동안 일부 정족수 인식의 조절을 받는 유전자들의 발현을 증가시키는 최종 신호 인자로 최근 제안되었으며, 그 신호는 또 다른 전사 조절 인자인 SoxR에 의해 매개된다고 제안되었다. 본 논문에서는 P. aeruginosa에서 새롭게 발견, 제안되고 있는 이들 신호 전달 물질들에 대해 자세히 다루어 보기로 한다.

• Journal of Cerebrovascular and Endovascular Neurosurgery
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• 제26권2호
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• pp.187-195
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• 2024

Perianeurysmal cysts are a rare and poorly understood finding in patients both with treated and untreated aneurysms. While the prior literature suggests that a minority of perianeurysmal cysts develop 1-4 years following endovascular aneurysm treatment, this updated review demonstrates that nearly half of perianeurysmal cysts were diagnosed following aneurysm coiling, with the other half diagnosed concurrently with an associated aneurysm prior to treatment. 64% of perianeurysmal cysts were surgically decompressed, with a 39% rate of recurrence requiring re-operation. We report a case of a 71-year-old woman who presented with vertigo and nausea and was found to have a 3.4 cm perianeurysmal cyst 20 years after initial endovascular coiling of a ruptured giant ophthalmic aneurysm. The cyst was treated with endoscopic fenestration followed by open fenestration upon recurrence. The case represents the longest latency from initial aneurysm treatment to cyst diagnosis reported in the literature and indicates that the diagnosis of perianeurysmal cyst should remain on the differential even decades after treatment. Based on a case discussion and updated literature review, this report highlights proposed etiologies of development and management strategies for a challenging lesion.