• Communications for Statistical Applications and Methods
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• 제26권2호
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• pp.163-173
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• 2019

Simon's two-stage designs are frequently used in phase II single-arm trials for efficacy studies. A concern of safety studies is too many patients who experience an adverse event. We show that Simon's two-stage designs for efficacy studies can be similarly used to design a two-stage safety study by modifying some of the design parameters. Given the type I and II error rates and the proportion of adverse events experienced in the first stage cohort, we prescribe a procedure whether to terminate the trial or proceed with a stage 2 trial by recruiting additional patients. We study the relationship between a two-stage design with a safety endpoint and an efficacy endpoint as well as use simulation studies to ascertain their properties. We provide a real-life application and a free R package gen2stage to facilitate direct use of two-stage designs in a safety study.

• The Korean Journal of Ecology
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• 제21권2호
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• pp.169-174
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• 1998

This is the review of vegetational history of the post-glacial period in Korea. most of studies for vegetational changes are located in the lowland alluvial plain, especially below the hilly zone of western and eastern coastal regions of Korea. A couple of methods, pollen analysis and radiocarbon dating, have been employed in these studies. These results lead us to establish the pollen zonation in Korea as the followings. Yasuda et al.(1980) classified six period in Yongrang lake of sokcho. These are as follow I. 17,000-15,000yr B.P.: Picea, Abies, Pinus(Haploxylon), Larix stage, II.15,000-10,000yr B.P:Herb, Pteridophyta stage, III.10.000-6,700yr BP.:Quercus stage, IV.6,700-4,500yr B.P.:Pinus, Quercus, Carpinus stage, V.4,500-1,400yr B.P.:Quercus. Pinus stage, VI.1,400yr B.P.-present: Pinus, Herbs stage. Jo(1979) also divided the period into two stages from the outcomes of analysis done in Jumoonjin and other sites I.10,000-6,000yr B.P.:Quercus stage, II.6,000-present: Pinus-Quercus stage, and three substages: IIa.6,000-3,400 yr B.P.:lower Pinus stage, IIb.3,400-2,000yr B.P.:Pinus-Quercus stage, IIc.2,000-present: Pinus stage. Choi(1993, 1996) divided the period into three stages: I.6,000-5,000yr B.P.:Alnus, Quercus stage, II.5,000-4,000yr B.P.: Alnus, Quercus, Pinus stage, III.4,500-2,600yr B.P.: Alnus, Pinus stage. In the period around 6,000yr B.P. distinct dominant species clearly occupied the lowland of the eastern and western coasts. Thus, this strongly supports the fact that even if Korea experienced its warm and wet climate after the lateglacial, it underwent a different environmental change, dry climate, compared to the regions of Japan.

• 한국지구과학회지
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• 제24권1호
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• pp.36-45
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• 2003

This study is made for examining the characteristics of the lead-zinc deposition from the mineralogy of pyrrhotite at the Yeonhwa 1 Mine, Korea. The pyrrhotite of the Yeonhwa 1 mine is divided two species; the pynhotites I and II. The pyrrhotite I that represents the product in Stage II mineralization is characterized by hexagonal pyrrhotite occurring as the mechanical mixtures of hexagonal and monoclinic phases with various proportion. These mixtures might be formed from 'primary' hexagonal pyrrhotite by the subsequent retrograde reaction and/or by the influence of later mineralization in Stage III. Whereas the pyrrhotite II crystallized out in later Mineralization Stage III (hydrothermal stage) is always monoclinic variant with ferromagnetic properties; no two phase mixtures have been recognized.

• 한국양식학회지
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• 제17권3호
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• pp.221-227
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• 2004

본 연구에서는 황복, T. obscurus의 초기발달동안 자치어의 성장과 생존에 미치는 먹이 종류와 염분별 영향을 조사하였다. 먹이별 실험에서는 Artemia공급 시기인 부화 25일의 자어를 이용해 Artemia (대조구)와 5가지의 먹이 (실지렁이, 물벼룩, 바지락육질, 배합사료, 곤쟁이)를 30일간 혼합 공급하여 실험구별 성장과 생존율을 비교하였다 염분별 실험에서는 일령 15일 자어(전장 5.8$\pm$0.4 mm: Stage I), 일령 36일 치어(전장 12.0$\pm$0.2 mm: Stage II) 및 일령 70일 치어(전장 44.5$\pm$0.7mm: Stage III)를 대상으로 4개의 염분 농도구(0, 10, 20 및 30 psu)를 설정하여 성장과 생존을 비교분석하였다. 먹이실험 결과, 성장도는 배합사료, 실지렁이, 물벼룩 공급구들이 비교적 양호하게 나타났으나, 생존율은 물벼룩 공급구가 가장 높게 나타났으며, 빠른 성장을 보였던 배합사료와 실지렁이 혼합 공급구는 오히려 낮은 생존율을 나타내었다. 염분별 실험에서는 Stage I 경우 성장에 있어 염분별 뚜렷한 차이를 찾아 볼 수 없었으나, 생존율은 10∼20 psu구에서 높게 나타났다. 또한 Stage II의 경우 성장과 생존 모두 10∼20 psu에서 양호하였으며, Stage III에서는 0∼30 psu의 모든 염분 조건에서 정상적인 성장과 생존을 나타내었다.

• 한국환경농학회지
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• 제38권1호
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• pp.47-53
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• 2019

BACKGROUND: This experiment was conducted to examine the effects of organic Se concentration and the number of foliar applications on growth characteristics and Se content in rice. METHODS AND RESULTS: A series of multiple foliar applications were performed at (1) 3 times (maximum tillering stage + booting stage + heading stage), (2) 4 times I (effective tillering stage + maximum tillering stage + booting stage + heading stage), (3) 4 times II (maximum tillering stage + booting stage + heading stage + grain filling stage) according to the development stage. Each set of the foliar application plots was treated with 0, 10, 20, 40, 60, 100 ppm of Se and with mixed pesticide ($P^*$ + Se 40 ppm) in which the treatment time was the same as that of the treatment 4 times II. The total cultivation period of rice was 184 days. Se contents in rice (brown rice, white rice) were analyzed by ICP. CONCLUSION: The number of grains per head tended to decrease with increasing concentrations of organic Se in all treatments. However, number of panicles per hill did not show statically significant differences between the 3 times and 4 times I treatments. The grain yield decreased with the 3 times and 4 times II, but there was no significant difference in 4 times I. Se content in brown rice was the highest at 100 ppm Se (5268.64) treatment and lowest at 10 ppm Se ($1269.19{\mu}g{\cdot}kg^{-1}$) treatment. Se content in the polished rice was the highest at 100 ppm Se (5047.33) treatment and lowest at 10 ppm Se ($885.05{\mu}g{\cdot}kg^{-1}$) treatment. The higher selenium was treated, the higher Se content was found in the rice (brown rice, polished rice).

• Radiation Oncology Journal
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• 제16권4호
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• pp.425-431
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• 1998

목적 : 초기 비소세포 폐암환자의 치료시 늑막하병변이 있는 경우에 치료후 결과에 어떤 영향을 주는지를 분석하고, 이 결과를 토대로 향후 치료방침의 결정에 도움을 주기 위해서 본 연구를 하였다. 대상 및 방법 : 1990년 12월부터 1996년 9월까지 동아대학병원에서 절제가능한 비소세포 폐암으로 진단받고 수술을 받은 환자 91명중 제 I병기와 제 II병기환자 66명을 대상으로 후향적 분석을 하였다. 66명중 늑막하병변이 있는 경우는 22명이었으며, 제 I병기(T1N0, T2N0)에서 늑막하병변이 있는 경우는 15명/44명(34.1$\%$)이었으며, 제 II병기(T1N1, T2Nl, T3No)에서 늑막하병변이 있는 경우는 7명/22명(31.8$\%$)이었다. 수술후 보조요법으로서 전신 항암요법은 시행되지 않았고, 방사선치료는 7명에서 시행되었다. 최소 추적관찰기간은 8개월이며 최대추적관찰기간은 84개월이며, 평균 추적관찰 기간은 33.2개월(중앙값; 29.5개월)이었다. 생존율은 Kaplan-Meier법으로 분석하였고, 서로간의 성적비교는 log-lank test를 이용하였다. 결과 : 전체환자의 3년 생존율은 69.5$\%$였다. 전체환자에서 늑막하병변이 있는 경우와 없는 경우의 3년 생존율은 각각 35.5$\%$와 84.6$\%$였으며, 통계학적으로 의미있는 차이를 보였다(p=0.0017). 제 I병기에서 늑막하병변이 있는 경우와 없는 경우의 3년 생존율은 각각 33.1$\%$와 92.3$\%$였으며, 통계학적으로 의미있는 차이를 보였다(p=0.001). 제 II병기에서 늑막하병변이 있는 경우와 없는 경우의 3년 생존율은 각각 53.3$\%$와 45.7$\%$였으며, 통계학적으로 차이는 없었다 (p=0.911). 제 I병기환자 44명중 원발종양의 크기가 3cm이상인 경우(T2, 34명)는 늑막하병변이 있는 경우와 없는 경우의 3년 생존율은 각각 27.3$\%$와 90.3$\%$였으며, 통계학적으로 의미있는 차이를 보였다(p=0.009). 국소재발은 늑막하병변이 있는 경우에는 제 I병기에서 2명/15명(13.3$\%$), 제 II병기에서 2명/7명(28.6$\%$)에서 재발하였고, 늑막하병변이 없는 경우에는 제 I병기에서 4명/29명(13.8$\%$), 제 II병기에서 2명/14명(14.3$\%$)에서 국소재발을 보였다. 원격전이는 늑막하병변이 있는 경우에는 제 I병기에서 5명/15명(33.3$\%$), 제 II병기에서 2명/7명(28.6$\%$)에서 원격전이를 보였고, 늑막하병변이 없는 경우에는 제 1병기에서 2명/29명(6.9$\%$), 제 II병기에서 4명/14명(28.6$\%$)에서 원격전이를 보였다. 결론 : 초기 비소세포 폐암환자의 예후에 있어서 늑막하병변의 유무가 중요한 역할을 하는 것으로 생각되며, 특히 임파선 전이가 없는 72병기의 경우 늑막하병변이 있으면 늑막하병변이 없는 경우에 비해 생존율에서 현저한 차이를 보였다.

• 자원환경지질
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• 제39권1호
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• pp.53-61
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• 2006

Geochemical and sedimentological analyses of sediment piston core were used to trace paleoceanographic environmental changes in the East China Sea. The analytical results revealed three lithostratigraphic units (I, II, and III) corresponding to a highstand stage, a transgressive stage, and a lowstand stage, respectively. Accelerator mass spectrometry (AMS) $^{14}C$ dated the boundaries between the units as 7 ka and II ka. That is, Unit I extended from the present to 7 ka, Unit II occupied a transitional episode from 7 to 11 ka, and Unit III was older than 11 ka. The transitional episode was characterized by sudden fluctuations in various geochemical proxies. Most strikingly, there was a gradual upward increase in both carbonate and total organic carbon (TOe) contents post-7 ka, during which time the ${\delta}^{l3}C$ values of organic material increased to a constant value. The gradual upward increase in the TOC and $CaCO_3$ contents in Unit I were accompanied by slight variations in grain size that probably reflect a stable modern oceanographic environment. Within Unit II (7 to 11 ka), the geochemical signals were characterized by abrupt and steep fluctuations, typical of a transgressive stage. Vertical mixing may have provoked an increase in productivity during this interval, with large amounts of terrigenous organic matter and/or freshwater being supplied by neighboring rivers. The geochemical signals remained stable throughout Unit III but exhibited different patterns than signals in Unit I. The high terrigenous organic matter content of Unit III suggests correspondence to a lowstand stage.

• 한국균학회지
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• 제37권2호
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• pp.150-154
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• 2009

The diversity of microflora according to growth stage of Pleurotus ostreatus and the correlation between microbe and medium fermentation were investigated. In farmhouse I, the aerobic bacteria and fungi as longer of growing period were increased. And, thermophilic bacteria and fluorescent Pseudomonas sp. showed high density at the early stage of spawn inoculation. The thermophilic actinomycetes were distributed evenly during all the growing period, but mesophilic actinomycetes were not observed. In farmhouse II, thermophilic actinomycetes were not observed in fermented medium and density of fungi were suddenly increased at 60 days after spawn inoculation. And also, mushrooms can hardly be harvested due to Penicillium spp. After medium fermentation, density of aerobic bacteria, thermophilic bacteria, and fluorescent Pseudomonas sp. was higher at farmhouse I than those of farmhouse II. In farmhouse I, Bacillus sp. and Pseudomonas sp. dominated at early stage of mushroom growth but as time goes by, density of Bacillus sp. was higher than the others. And also, the kind of microbe showed a few at early stage of mushroom growth but increased as time goes by. In farmhouse II, Bacillus sp. was dominated at early stage of mushroom growth. And the growth of Bacillus sp. and Pseudomonas sp. showed intersect aspect each other in the farmhouse I but Bacillus sp. dominated during all growth periods in the farmhouse II.

• Radiation Oncology Journal
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• 제11권1호
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• pp.159-166
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• 1993

A retrospective analysis was done for 69 patients with Stage I and II non-Hodgkin's lymphoma who were treated from May 1981 to December 1990, in the Department of Radiadtion Oncology, Korea University Hospital. We used Ann Arbor Staging system and Working Formulation for histological classification. Forty-three patients (43/69, $62.3{\%}$) were Stage I and 26 patients (26/69, $37.7{\%}$) were Stage II, and B symptom was found in $10.1{\%}$ (7/69). Nodal lymphoma was $21.7{\%}$ (15/69); 14 patients with supradiaphragmatic disease and 1 patient with infradiaphragmatic disease. Extranodal lymphoma was $78.3{\%}$ (54/69): $64.8{\%}$ (35/54) for head and neck, $25.9{\%}$ (14/54) for gastrointestinal tract. Histologically, low grade consists of $8.7{\%}$ (6/69), intermediate grade $84.2{\%}$ (56/69), high grade $10.1{\%}$ (7/69), and diffuse large cell type was the most frequent form with 36 patients (36/69, $52.2{\%}$). Eighteen patients ($26.1{\%}$) were treated with radiation therapy alone,20 patients ($29.0{\%}$) with radiation therapy combined with chemotherapy, 15 patients ($21.7{\%}$) with radiation therapy combined with surgery and chemotherapy, Median survival duration was 28 months, and the range of survival time was from 1 month to 134 months. Overall five-year survival rate for Stage I and II disease was $54.2{\%}$, with $64.5{\%}$ for Stage I and $37.1{\%}$ for Stage II. For nodal lymphoma,5-year survival rate was $45.9{\%}$, and $56.5{\%}$ for extranodal lymphoma; $60.6{\%}$ for head and neck, $52.9{\%}$ for GI tract primary disease. Local control rate for all patients was $88.4{\%}$ (61/69), with $80{\%}$ (12/15) for nodal lymphoma and $90.7{\%}$ (49/54) for extranodal lymphoma. The total failure rate was $34.8{\%}$ (24/69). Five of 24 ($20.8{\%}$) patients who were failed developed local failure only, $12.5{\%}$ (3/24) local failure with distant failure, and distant failure only were found in $66.7{\%}$ (16/24). Between nodal lymphoma and extranodal lymphoma, there was no significant survival difference, but extranodal lymphoma showed higher incidence.

• 대한핵의학회지
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• 제37권2호
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• pp.94-102
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• 2003

목적: 아세타졸아마이드를 이용한 뇌혈류 SPECT는 폐쇄성 뇌혈관질환이 있는 환자에서 혈역학적 부전을 평가 하는데 유용하다. 본 연구는 아세타졸아마이드 부하 $^{123}I-IMP$ SPECT를 실시하여 뇌국소부위의 혈역학적 부전의 정도를 정확히 평가할 수 있는지를 살펴보았다. 대상 및 방법: 뇌혈관 질환이 의심되는 18명의 (남: 16, 여: 2, 평균연령 61세) 환자를 대상으로 하였다. 뇌국소부위의 혈관확장 예비능을평가하기 위하여 아세타졸아마이드 투여후 $^{123}I-IMP$ SPECT를 실시하였다. PET은 SPECT 검사 전후로 2주 이내의 간격을 두고 실시하였으며, 뇌혈류, 산소추출분획, 뇌산소대사율 및 뇌혈액량을 구하였다. 모두 46개의 직사각형의 관심영역 (ROIs)을 4개의 다른 뇌단층면에서 직접그리고 병변 부위의 관심영역내에서의 $^{123}I-IMP$ 섭취와 반대측의 동일영역의 관심영역에서 $^{123}I-IMP$ 섭취비율인 AI 를 구하여 PET 에서 얻어진 자료들과 비교하였다. 결과: 18명의 환자의 414 개의 해부학적 영역에서의 뇌의 혈역학적인 평가는 각 환자의 산소수출분획과 뇌혈류/뇌혈액량에 따라 정상 (n=107), stage I (n=117) 또는 stage II (n=140) 로 나누었다. 혈관 확장 예비능을 나타내는 ${\triangle}AI$ (아세타졸아마이드투여시 AI 값-기저상태의 AI 값) 의 값은 정상, stage I 및 stage II 에서 각각 $-6.25{\pm}7.77%,\;-10.38{\pm}10.41%$ 및 $-13.30{\pm}10.51%$으로 세군간에 유의한 차이가 있었다 (p<0.05). 뇌혈관 협착이 있는 대뇌반구에서 ${\triangle}AI$와 뇌혈류량, 산소추출분획 및 뇌혈액량/뇌혈류량의 상관계수는 각각 0.20, -0.28 및 -0.28로 통계적으로 유의한 상관관계를 보였다(p<0.01). 결론: 정상인과 stage I 그리고 stage II 의 혈역학적부전 환자들간의 뇌혈관확장 예비능에 유의한 차이가 있었으며, 이러한 결과로 볼 때 아세타졸아마이드 부하에 대한 국소뇌혈류의 변화는 뇌관류압에 대한 보상적 혈관확장의 정도를 비교적 정확히 반영할 수 있다고 볼 수 있다.