• Journal of the Korean Data and Information Science Society
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• v.25 no.5
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• pp.971-986
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• 2014

When thousands of hypotheses are tested simultaneously, the probability of rejecting any true hypotheses increases, and large multiplicity problems are generated. To solve these problems, researchers have proposed different approaches to multiple testing methods, considering family-wise error rate (FWER), false discovery rate (FDR) or false nondiscovery rate (FNR) as a type I error and some test statistics. In this article, we discuss Bonferroni (1960), Holm (1979), Benjamini and Hochberg (1995) and Benjamini and Yekutieli (2001) procedures based on T statistics, modified T statistics or local-pooled-error (LPE) statistics. We also consider Sun and Cai (2007) procedure based on Z statistics. These procedures are compared in the simulation and applied to Arabidopsis microarray gene expression data to identify differentially expressed genes.

• 종축개량
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• v.20 no.2
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• pp.118-121
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• 1998

인공수정은 정확한 발견, 고도의 기술, 우군의 수태율, 정액의 질 등이 정상적인 임신을 하기 위해 필요한 요소들이다. 분만율을 높이기 위해 가능하는 한 위의 모든 사항을 염두에 두고 경영을 해야 ?다.

• Journal of the Korean Society of Radiology
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• v.15 no.2
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• pp.147-152
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• 2021

This study is a retrospective analysis of the results of tests at three general hospitals in Busan that perform mammography using digital mammography devices. There were 5,320 people in the study, and the results of their breast cancer screening were analyzed to verify the efficacy of breast cancer screening for digital mammography. The average age of patients who performed breast cancer screening was 57.7 years (range 30 to 87 years), and the cancer detection rate was 26, with 4.6 cases per 1,000 people. According to the cancer detection rate by risk factor in patients who conducted breast cancer screening, breast cancer was found in patients without underlying diseases more than in patients with underlying diseases. Additional ultrasound examinations show that the gastronomic rate identified is 3.6%, which is relatively very low compared to that of the Film-Screen system.

• The Korean Journal of Applied Statistics
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• v.21 no.1
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• pp.65-80
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• 2008

Small scale time-course microarray experiments are those which have a small number of time points. They comprise about 80 percent of all time-course microarray experiments conducted up to 2005. Several statistical methods for the small scale time-course microarray experiments have been proposed. In this paper we applied three methods, namely, QR method, maSigPro method and STEM, to a real time-course microarray experiment which had six time points. We compared the performance of these three methods based on a simulation study and concluded that STEM outperformed, in general, in terms of power when the FDR was set to be 5%.

• 건강소식
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• v.38 no.9
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• pp.4-5
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• 2014

한국건강관리협회 메디체크는 높은 흡연율, 잦은 술자리와 각종 스트레스, 운동부족이라는 건강위험요소에 노출된 현대인들의 건강을 지키고자 정확하고 체계적인 위 대장 검진 서비스를 제공하고 있다. 위장 및 대장 질환 중에서도 위암과 대장암은 조기에 발견해야 완치율이 높아지기 때문에 정기적으로 건강검진을 받는 것이 무엇보다 중요하다. 이 외에도 메디체크는 위장 및 대장 질환 유소견자나 경계인의 건강회복을 위해 식습관 및 생활습관 상담을 실시하는 등 국민건강증진에 앞장서고 있다.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.1
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• pp.60-67
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• 2014

The comparisons between cellulolytic bacteria adhesion on rice straw and fiber digestion in time course during rumen fermentation were studied in situ. The adhesions of cellulolytic bacteria, F. succinogenes. R. albus and R. flavefaciens, were measured by RT-PCR. When the rice straws were incubated at 0. 2, 4, 8, 12 and 24 hours of the in situ rumen, straw was degraded with increasing speed during the incubation and showed the highest disappearance increasing rate (DM g/h) from 8 to 12 hour. The adhesions of F. succinogenes, R. flavefaciens and R. albus were achieved above 80% in 1 hour of in situ rumen fermentation and then keep adhesive population up after the time of fermentation. When the in situ samples were collected at 0, 5, 10, 30 and 60 min to detect the early stages of adhesion on the rice straws ingested into rumen, the numberous adhesive colony of F. succinogenes, R. flavefaciens and R. albus were detected in 5 min. In case of rice straw treated with 0, 2, 4 and 8% NaOH, all of three cellulolytic bacteria showed the increasing trends of adhesion with increasing DM disappearance of rice straw by higher concentration of NaOH at 12 hour of in situ. However, there were showed respectively difference at 24 hour. The present results gave certain evidence that adhesion of cellulolytic bacteria is definitely achieved in early stage of roughage ingestion into rumen, their colony develop the stable communities on roughage in process of rumen fermentation and then fiber degradation is accelerated.

• Korean Journal of Head & Neck Oncology
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• v.26 no.2
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• pp.178-182
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• 2010

서 론 : 두경부암의 예후에 가장 중요한 인자는 진단시 병기와 치료 후 재발의 유무이다. 따라서, 재발 병변을 조기에 발견하는 것이 매우 중요하다. 본 연구에서는 두경부암 환자의 추적 관찰에서 $^{18}F$-FDG PET/CT의 유용성에 대해 알아보고자 하였다. 대상 및 방법 : 2004년 4월부터 2008년 8월까지 고려대 안암병원에서 두경부암으로 치료를 완료한 후 추적관찰이 가능하였던 88 예의 환자를 대상으로 하였다. 환자는 본원의 두경부암 추적관찰 양식에 따라 술 후 6, 12개월째 $^{18}F$-FDG PET/CT를 시행하였으며, 원발부위 및 경부 재발, 원격전이와 중복암의 진단에 있어 $^{18}F$-FDG PET/CT의 민감도, 특이도, 양성예측율, 음성예측율을 평가하였고, 기존의 추적관찰 방법과 이를 비교하였다. 결 과 : 원발부위 재발의 진단에 있어 민감도, 특이도, 양성예측율, 음성예측율은 각각 95%, 97%, 90%, 98% 였다. 경부전이 재발의 진단에 있어서는 각각 94%, 98%, 83%, 99%였으며, 원격전이 및 이차암 진단에 있어서는 94%, 100%, 100%, 99%였다. 원발부위 재발은 고식적인 진단 방법, 원격전이와 이차암은 $^{18}F$-FDG PET/CT가 진단에 의미있게 유리하였다. 결 론 : $^{18}F$-FDG PET/CT는 두경부암의 추적관찰 과정에서 재발 여부를 판정하는데 있어 매우 유용하며, 특히 원격전이 및 이차암의 발견에 있어 유용하다. 그러나, 위양성 및 위음성의 가능성으로 고식적인 진단 방법과 병행해야 진단의 효과를 높힐 것으로 생각된다.

• The Korean Journal of Nuclear Medicine
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• v.37 no.6
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• pp.374-381
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• 2003

Purpose: Determining an appropriate thresholding is crucial for PDG PET analysis since strong control of Type I error could fail to find pathological differences between eariy Alzheimer' disease (AD) patients and healthy normal controls. We compared the SPM results on FDG PET imaging of early AD using uncorrected p-value, random-field based corrected p-value and false discovery rate (FDR) control. Materials and Methods: Twenty-eight patients ($66{\pm}7$ years old) with early AD and 18 age-matched normal controls ($68{\pm}6$ years old) underwent FDG brain PET. To identify brain regions with hypo-metabolism in group or individual patient compared to normal controls, group images or each patient's image was compared with normal controls usingthe same fixed p-value of 0.001 on uncorrected thresholding, random-field based corrected thresholding and FDR control. Results: The number of hypo-metabolic voxels was smallest in corrected p-value method, largest in uncorrected p-value method and intermediate in FDG thresholding in group analysis. Three types of result pattern were found. The first was that corrected p-value did not yield any voxel positive but FDR gave a few significantly hypometabolic voxels (8/28, 29%). The second was that both corrected p-value and FDR did not yield any positive region but numerous positive voxels were found with the threshold of uncorrected p-values (6/28, 21%). The last was that FDR was detected as many positive voxels as uncorrected p-value method (14/28, 50%). Conclusions FDR control could identify hypo-metaboiic areas in group or individual patients with early AD. We recommend FDR control instead of uncorrected or random-field corrected thresholding method to find the areas showing hypometabolism especially in small group or individual analysis of FDG PET.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.3
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• pp.18-26
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• 1999

소프트웨어 개발과정에서는 설계 및 코딩에 의해서 프로그램 내에 많은 결함이 삽입되고 시험을 거치는 동안 결함은 발견되고 수정되어 진다. 이와 같은 반복 작업을 통해서 소프트웨어 내에 잠재하고 있는 에러들을 발견, 조치함으로써 소프트웨어 품질은 향상되고 품질에 대한 신뢰성이 높아진다. 본 논문에서는 위와 같은 소프트웨어 개발 과정을 거치는 동안에 많은 시험이 동반되고 이에 따른 시험의 여러 자원이 투입되는데 착안하여 소프트웨어 신뢰도가 성장되어 가는 과정에 수반된 시험능력을 기반으로 한 시험능력의존형 소프트웨어 신뢰도 성장모델을 살펴보고 이를 적용하여 개발중인 소프트웨어에 대한 시험능력 투입에 따른 신뢰도를 평가하였다. 또 S-Shaped Model에 의한 평가치와 비교하여 시험이 진행됨에 따라 소프트웨어 고장 발견율이 상승되는 것을 보였다.

• Journal of the Korean Society of Radiology
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• v.6 no.1
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• pp.63-71
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• 2012

This study aimed to evaluate the accuracy of breast cancer diagnosis of digital mammography which is in the highest interest of breast imaging test, and to investigate the characteristics of breast cancer patients. For this purpose, 57 breast cancer patients who underwent breast imaging test were examined between May 2010 and June 2011. The average age of the breast cancer patients was 50.8 years old, and the most frequently occurring location was the upper outer quadrant (UOQ), accounting for 33.3%. By age, the highest occurrence rate of breast cancer was the age group of 40~49, accounting for 42.1%. As for the breast composition of the breast cancer patients, fatty breast accounted for 31.6% (18/57) and dense breast for 68.4% (39/57), indicating that nearly 70% of the breast cancer patients have dense breast. It was found that the detection rate of breast cancer was the highest (45.3%) when both microcalcification and mass are simultaneously present in the radiographic lesion of the breast imaging. In dense breast, the mass without microcalcification was lower in detection rate than fatty breast. Accordingly, the mass is the cause of raising the false negative rate in dense breast. The findings show that the false negative rate of digital mammography was 7.0% and the sensitivity 93.0%. Also, the false negative rate of dense breast was 12.8%, and the sensitivity 87.2%, indicating that the sensitivity to breast cancer in this study was higher than the dense breast of previously reported screen film mammography.