• Journal of Gifted/Talented Education
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• v.22 no.3
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• pp.503-525
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• 2012

This study compared levels of mathematically talented students' statistical thinking with those of non-talented students in statistical modeling and sampling distribution understanding. t tests were conducted to test for statistically significant differences between mathematically gifted students and non-gifted students. In case of statistical modeling, for both of elementary and middle school graders, the t tests show that there is a statistically significant difference between mathematically gifted students and non-gifted students. Table of frequencies of each level, however, shows that levels of mathematically gifted students' thinking were not distributed at the high levels but were overlapped with those of non-gifted students. A similar tendency is also present in sampling distribution understanding. These results are thought-provoking results in statistics instruction for mathematically talented students.

• Journal of the Korean School Mathematics Society
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• v.24 no.2
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• pp.191-216
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• 2021

This study analyzes how statistical literacy is implemented along with the statistical problem-solving process as described in the Statistical Estimation Unit of the textbook by the 2015 revised mathematics curriculum. The analytical framework was developed from the literature, and consists of 'context', 'variability', 'mathematical and statistical knowledge', 'using of technological instruments', 'critical attitude', and 'communication'. From the perspective of the statistical problem-solving process, the analysis revealed that many tasks equivalent to 'Analyzing Data' but lacked tasks related to 'Interpreting Results' and 'Formulating Questions'. As a result of analyzing the reflection of each element of statistical literacy, 'mathematical and statistical knowledge' was the most common task, but 'critical attitude' and 'using of technological instruments' were rarely dealt with. Based on the results of this textbook analysis, it was intended to provide implications for improving the curriculum and the development of textbooks for the growth of statistical literacy.

• Radiation Oncology Journal
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• v.19 no.2
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• pp.107-112
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• 2001

Purpose : To determine the prognostic significance of p53 mutations in advanced supraglottic cancer patients. Material and Methods : Twenty-six patients with pertinent tissue materials among 60 patients diagnosed as advanced supraglottic cancer in Kyung Hee university hospital and received total or partial laryngectomy followed by radiation therapy were enrolled. Immunohistochemical staining using DO7 monoclonal antibody was peformed. Tumor specimens were analyzed for p53 mutations in exons 5 through 8 by using PCR-SSCP analysis followed by DNA sequencing of all variants. Results : p53 mutations were present in 8 cases among 26 patiets. Mutations within exon 5 were 3 cases, exon 6 were 4 cases, and exon 7 was 1 case. Mean survival time was 70.2 months in patients without mutations, 61.3 months with mutations but there was no statistically significant differences (p=0.596). Mutations were $25\%$ in stage III and $36\%$ in stage IV but there was no statistically significant differences (p=0.563). Mutations were $25\%$ in lymph node negative group and $42\%$ in lymph node positive group but there was no statistically significant differences (p=0.437). Conclusion : The presence of p53 mutation detected by PCR-SSCP is not associated with survival, stage and lymph node status.

• Journal of Educational Research in Mathematics
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• v.21 no.1
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• pp.17-32
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• 2011

This study investigated pre-service teachers' understanding of statistical sampling. The researchers categorized major topics related to sampling into representativeness of samples, sampling variability, and sampling distribution, and selected concepts connected to each topic. Findings on this study are as follows: Even though most of the pre-service teachers considered the random sampling bringing unbiased outcomes as a proper sampling method, only 64% of them recognized that sample is a quasi-proportional, small-scale version of population; Few pre-service teachers understood that more important is the size of sample, not the portion of sample to population, and half of them appreciated that the number of sampling has a powerful effect on drawing of reliable results than the size of sample; Few pre-service teachers understood that sampling distribute is irrelevant to the shape of population and has a symmetrical bell-shape.

• Journal of Korean Society of Forest Science
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• v.88 no.3
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• pp.408-418
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• 1999

On the basin of RAPD analysis, genetic diversity and structure of the natural populations of Abies holophylla was estimated by AMOVA procedure. The average value of percent of polymorphic markers was 71.9%. Most variation existed among individuals within population(80.2%). Genetic differentiation among populations(${\Phi}_{ST}$) was 0.198. When the populations were grouped as two region(i.e., Taebaek and Sobaek Mountain Regions), 8.5% of the total genetic variation was explained as regional differences. The heterogeneity of molecular variance among populations was investigated with Bartlett's test, which revealed that populations of Mt. Taebaek and Mt. Gariwang were more heterogeneous. Generally, the populations of Taebaek Mountain Reion were more heterogeneous than those of Sobaek Mountain Reion. Finally, the applicability of AMOVA to the populations frenetic study was discussed in comparison with other measures of genetic differentiation which were widely used.

• Proceedings of the Korean Information Science Society Conference
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• 2012.06c
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• pp.19-21
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• 2012

모든 암 세포는 체세포 변이를 동반한다. 따라서 암 유전체 변이 분석에 의하여 암을 발생시키는 유전자 및 진단/치료법을 찾아낼 수 있다. 본 연구에서는 차세대 시퀀싱 데이터를 이용하여 암 특이적 단이 반복 변이(copy number variation, CNV) 유형을 밝히는 새로운 알고리즘을 제안한다. 제안하는 방식은 암 환자의 정상 세포와 암세포로부터 얻어진 정상 유전체와 암 유전체를 동시 분석하여 각각 CNV 후보 영역을 추출하며, 통계적 유의성 분석을 통하여 암 특이적 CNV 후보 영역을 선별하고, 다음 후처리 과정에서 참조 표준 서열(reference sequence)에 존재하는 오류 영역 보정 작업을 수행하여 정확한 암 특이적 CNV 영역을 추출해 낸다. 또한 다수의 대용량 유전체 데이터 동시 분석을 위하여 맵리듀스(MapReduce) 기법을 기반으로 하는 병렬 수행 알고리즘을 제안한다.

• Korean Journal of Construction Engineering and Management
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• v.10 no.2
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• pp.75-83
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• 2009

PPC stands for the percentage of weekly assignments completed. It makes it possible to improve the performance of production planning and control systems. Recently, the cases of PPC application have been increasing because PPC is easy to apply to construction site. However, to evaluate the average of PPC or analyze PPC as time passes has some problem ; if PPC is the same, the average it is evaluated equally although there are variabilities in production system. Therefore, In order to evaluate the character of PPC in process of production this paper suggests the method of the evaluating PPC by using coefficient of variability besides PPC measurement.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.8 s.350
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• pp.35-43
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• 2006

In the paper, we propose a new method for power optimization that uses path balancing based on stochastic estimation of glitch in Statistical Static Timing Analysis (SSTA). The proposed method estimates the probability of glitch occurrence using tightness probability of each node in timing graph. In addition, we propose efficient gate sizing technique for glitch reduction using accurate calculation of sizing effect in delay considering probability of glitch occurrence. The efficiency of proposed method has been verified on ISCAS85 benchmark circuits with $0.16{\mu}m$ model parameters. Experimental results show up to 8.6% of accuracy improvement in glitch estimation and 9.5% of optimization improvement.

• School Mathematics
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• v.19 no.4
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• pp.691-712
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• 2017

It is an important to develop teachers' statistical reasoning or thinking by teacher education. In this study, the "comparing two data sets" tasks is focused as a way to develop pre-service elementary teachers' reasoning about core ideas of statistics such as distribution, variability, center, and spread. 6 teams of each 4 pre-service elementary teachers participated on the tasks and their presentations are analyzed based on Pfannkuch's (2006) teachers' inference model in comparing two data sets. As a result, they paid attention to the distribution and variability in the statistical problem solving by the "comparing two data sets" tasks, and used their contextual knowledge to make a statistical decision. In addition, they used some statistics and graphs as the reference for statistical communication, which is expected to provide implications for improving statistical education. The finding implies that the "comparing two data sets" tasks can be used to develop statistical reasoning of pre-service elementary teachers. Some recommendations are suggested for teacher education by these tasks.

• Journal of Acupuncture Research
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• v.23 no.5
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• pp.207-218
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• 2006

목적 : 심박수 변이도(Heart Rate Variability. HRV)를 통해 사암침법 치료법 중 심신 질환에 많이 적용되는 심정격 자침법과 자율신경계와의 관계를 살펴보고자 하였다. 방법 : 2006년 5월 1일부터 2006년 6월 31일까지 2개월간 특별한 과거력이 없는 건강인을 대상으로 실험군 37명을 사암침법 심정격을 자침하고 시술 전후에 HRV를 측정하여 별무처치 상태로 안정을 취한 후 측정한 대조군 21명과 비교하였다. 결과로 얻은 MHRT, SDNN, RMSSD, TP, LF, HF, LF/HF ratio 등의 수치 변화를 비교해 기록 시간 동안의 평균 심박수, 외부 스트레스에 대한 심박동의 변화상태, 심장에 관여하는 자율신경 중 부교감신경의 활동, 교감신경과 부교감신경의 균형 상태 등을 분석하였다. 결과 1. MHRT는 실험군에서 유의성이 있는 것으로 나타났다. 2. SDNN는 실험군 대조군 모두 통계적인 유의성이 없었다. 3. RMSSD은 실험군 대조군 모두 통계적인 유의성이 없었다. 4. TP는 실험군 대조군 모두 통계적인 유의성이 없었다. 5. LF, HF은 실험군 대조군 모두 통계적인 유의성이 없었다. 6. LF/HF ratio는 실험군에서 유의성이 있는 것으로 나타났다. 결론 : 부교감신경과 교감신경의 비교 지표로 다용되는 LF/HF ratio가 유의한 차이를 보여 심정격 자침이 자율신경계의 항진을 완화시키는 것으로 사료된다. 향후 환자의 병인과 상태에 따라 실증과 허증으로 구분하여 시술하는 등의 추가적인 연구가 필요할 것으로 사료된다.