• Communications for Statistical Applications and Methods
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• v.15 no.5
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• pp.737-752
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• 2008

About 1800, mathematicians combined analysis of error and probability theory into error theory. After developed by Gauss and Laplace, error theory was widely used in branches of natural science. Motivated by the successful applications of error theory in natural sciences, scientists like Adolph Quetelet tried to incorporate social statistics with error theory. But there were not a few differences between social science and natural science. In this paper we discussed topics raised then. The problems considered are as follows: the interpretation of individual man in society; the arguments against statistical methods; history of the measures for diversity. From the successes and failures of the $19^{th}$ century social statisticians, we can see how statistics became a science that is essential to both natural and social sciences. And we can see that those problems, which were not easy to solve for the $19^{th}$ century social statisticians, matter today too.

• Journal of Environmental Impact Assessment
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• v.15 no.5
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• pp.323-337
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• 2006

This work discussed the species composition, phylogeny, spatio-temporal distribution, ecology and natural history of North Korean Pinaceae or pine tree family, which seems to be important to maintain nature and ecosystem in the Korean Peninsula. Out of five genera and sixteen species of Pinaceae of the Korean Peninsula, North Korea contains four genera and eleven species of Pinaceae, including Pinus densilflora, P. koraiensis, P. pumila, Picea jezoensis, P. koraiensis, P. koraiensis var. koraiensis, P. pungsanensis, Larix gmelini, L. gmelinii var. olgensis, Abies holophylla and A. nephrolepis. In terms of phylogeny Pinus is closely related to Picea, and followed by Larix. Abies is close to Tsuga which only occur at Ullung Island. Distributional pattern of North Korean Pinaceae can be classified into four types; three species of nation-wide montane type i.e., Pinus densilflora, P. koraiensis and Abies holophylla, four species of central and northern subalpine type, i.e., Pinus pumila, Picea koraiensis, Larix gmelini and Abies nephrolepis, one nation-wide subalpine type, Picea jezoensis, and three species disjunctive to north type, i.e., Picea koraiensis var. koraiensis, P. pungsanensis, and Larix gmelinii var. olgensis. Pinaceae species occurring on the alpine and subalpine belts of North Korea, such as Pinus koraiensis, P. pumila, Picea jezoensis, P. koraiensis, P. koraiensis var. koraiensis, P. pungsanensis, Larix gmelini, L. gmelinii var. olgensis and A. nephrolepis are considered as the glacial descendant from the boreal region. Those species might have migrated from the north during the Pleistocene glacial epochs in search of favourable condition, and since the Holocene period they survived on the hostile alpine and subalpine environments, in which they are more competitive than warmth-tolerant temperate vegetation. Certain species, such as Picea pungsanensis, is segregated on the isolated mountains since the Pleistocene period, and forced to adapt to local environment, and eventually became an endemic species of North Korea. Recent rapid global warming trend especially in northern high mountains of North Korea could cause an unfavourable environment for the survival of cold-tolerant Pinaceae of the alpine and subalpine belts. Pinus densiflora, which is occurring on the montane belt might faced with difficulties due to both the deforestation and the outbreak of insect-borne disease, such as Bursaphelenchus xylophilus.

• The Journal of Korean Medicine
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• v.27 no.4
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• pp.215-224
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• 2006

Objectives : In order to apply useful data to clinical practice, we undertook this study and tried to find factors related with sequelae of facial palsy in relation with patients' age and gender distribution, past history with the disease, condition before onset, duration of recovery time, existence of remaining sequelae, types of the sequelae, and duration for sequelae to disappear. Methods : We evaluated patients' condition (fatigue, stress, chills, cold and so on), past history (diabetes mellitus, hypertension, stroke, herpes zoster, cancer and so on), duration of recovery time, types of the sequelae, age and sequelae distribution as to when the treatments were started as we examined 473 patients who were diagnosed with facial palsy, and visited the Out-patient Department of Acupuncture and Moxibustion of Bundang Oriental Medicine Hospital of Dongguk University through 2003 and 2004. Results : The sequelae of facial palsy were not significantly relevant to the signs found before facial palsy occurred(fatigue, stress, chills, and cold), or to patients' past history (hypertension, diabetes mellitus, facial palsy, herpes zoster). The duration of recovery time was within 30 days for 45.3% of the patients examined in this study, and within 90 days for 72.6%. Evaluating the existence of sequelae in relation to age, we found more in the group comprised of patients aged 50 and over than under 50. We found more sequelae in the group which is consisted of patients who had not been treated until 6 days after than within 5 days from the onset. Conclusion: Attention to sequelae will be needed for patients aged 50 and over and who were not treated until 6 days after the onset, as they had more sequelae.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.52.1-52.1
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• 2017

Galaxy clusters are the most massive gravitationally bound systems and thus probably the most recent objects to form. One of promising routes to understand the assembly history of galaxy clusters is to measure observable quantities of components in clusters that are sensitive to the evolutionary state of the cluster. Recent deep observations on the nearby clusters show distinct diffuse intracluster light (ICL), that the light from stars are not bound any individual cluster galaxy, however until now this component has not been well studied due to its faint nature, with typical brightness of ~100 times fainter than the sky background. As shown in galaxy cluster simulation studies, the ICL abundance increases during various dynamical exchanges of galaxies such as the disruption of dwarf galaxies, major mergers between galaxies and the tidal stripping of galaxies. Thus, the ICL is an effective tool to measure the evolutionary stage of galaxy clusters. Moreover, the investigation of the ICL evolution mechanism will allow us understand the galaxy evolution process therein. In this pilot study, we target the Coma cluster, where the existing ICL studies are limited only in the central region. With large and uniform deep optical images from the Subaru telescope, available only recently (Okabe et al. 2014), we are developing a robust ICL measurement technique, extracting the ICL surface brightness and color profiles, which will allow us to study the origin of the ICL and its connection to the evolutionary history of the Coma cluster. For the next phase, we plan to utilize the plenty of spectroscopy data from the MMT telescope to compare ICL properties with the star formation history of the brightest cluster galaxies (BCG), and discuss the ICL formation mechanism of the Coma cluster by comparing the distribution of cluster galaxies with the distribution of diffuse light inside the Coma cluster.

• ALGAE
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• v.36 no.1
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• pp.13-24
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• 2021

The present-day genetic structure of macroalgal species reflects both geographical history and oceanic circulation patterns as well as anthropogenic introduction across native ranges. To precisely understand the genetic diversity and how the factors shape the current population structure of Gloiopeltis furcata sensu lato, we determined the mitochondrial 5' end of cytochrome c oxidase subunit I (COI-5P) sequences for 677 individuals sampled from 67 sites spanning almost the entire distribution range in Korea and Japan. Results from the phylogenetic analysis and haplotype distribution revealed eleven distinct lineages within G. furcata s.l. along the Korea-Japan coastal areas and displayed divergent phylogeographic patterns among lineages. Despite the closely related lineages distributed in same habitats as high rocky intertidal zone, they display different phylogeographic patterns among lineages. The populations from the south of Korea-Japan harbored the highest genetic diversity and unique endemism in comparison with other populations in the distribution range. This could be the evidence of southern refugia for G. furcata s.l. in the Northwest (NW) Pacific and the recent migration from native to introduced region. The reason is that an exceptional distribution pattern was found high genetic diversity in Hakodate of Japan where is the northern location in the NW Pacific. Our results imply the contemporary influence on the distribution due to current circulation pattern and anthropogenic effects. These phylogeographic findings provide the important insight into cryptic species diversity and the detailed distribution pattern of Gloiopeltis in the NW Pacific.

• Archives of Craniofacial Surgery
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• v.25 no.1
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• pp.11-16
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• 2024

Background: The pathogenesis of orofacial cleft (OFC) is multifactorial, involving both genetic and non-genetic factors, the latter of which play a key role in the development of these anomalies. This paper addresses the incidence of OFC in Indonesia, with a focus on identifying and examining the distribution of contributory factors, including parental medical history, pregnancy history, and environmental influences. Methods: The study was conducted through the collection of primary data. An interdisciplinary research team from Indonesia administered a standardized questionnaire to parents who had children with OFC and who had provided informed consent. The case group comprised 133 children born with cleft lip and/or palate, and the control was 133 noncleft children born full-term. The risk factors associated with OFC anomalies were analyzed using the chi-square test and logistic regression. All statistical analyses were performed using SPSS version 25. A p-value of 0.05 or less was considered to indicate statistical significance. Results: The study comprised 138 children, of whom 82 were boys (59.4%) and 56 were girls (40.6%). Among them, 45 patients (32.6%) presented with both cleft lip and cleft palate, 25 individuals (18.1%) had a cleft palate only, and 28 patients (20.3%) had a cleft lip only. OFC was found to be significantly associated with a maternal family history of congenital birth defects (p<0.05), complications during the first trimester (p<0.05), consumption of local fish (p<0.05), caffeine intake (p<0.05), prolonged medication use (p<0.05), immunization history (p<0.05), passive smoking (p<0.05), and X-ray exposure during pregnancy (p<0.05). Conclusion: The findings indicate close relationships between the incidence of OFC and maternal medical history, prenatal factors, and environmental influences.

• Earthquakes and Structures
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• v.5 no.6
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• pp.753-779
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• 2013

One of the most important issues in progressive collapse mechanism of the buildings is evaluation of the collapse distribution in presence of the earthquake loads. Here, collapse propagation is investigated by tracking down the location and type of the collapsed beam and column elements, from the first element to the entire buildings. 6-story reinforced concrete ordinary moment resisting frame buildings with one directional mass eccentricity of 0%, 5%, 15% and 25% are studied to investigate differences among the progressive collapse mechanism of the regular and irregular buildings. According to the results of the nonlinear time history analyses, there are some patterns to predict progressive collapse scenarios in beam and column elements of the similar regular and irregular buildings. Results also show that collapse distribution patterns are approximately independent of the earthquake records.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.750-753
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• 2005

An equivalent linearization technique based on Rayleigh peak distribution for friction damper and brace system (FDBS) under stochastic excitation is proposed. For verification, shaking table test of a small scale 3-story building model with the FDBS is conducted for various slip moment levels. Using experimental result, equivalent linearization of the FDBS is conducted based on Rayleigh peak distribution, which is compared with measured peak distribution. For comparative study, model updating technique is applied based on identified modal properties. Finally, complex modal analysis and time history analysis for the obtained equivalent linear systems are conducted and compared with experimental result

• Journal of Korea Technology Innovation Society
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• v.9 no.3
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• pp.471-495
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• 2006

This paper reviews the distribution patterns of research equipments in Korea. We start, however, discussion with the introduction to research equipments, theoretical issues and rationale for government intervention. Nation-wide distribution of research equipments is shown by region, type of institution, university, and major equipment. Old patterns are derived from the history of equipping science, and three new current patterns are introduced. Based on this discussion, we recommend policies for research equipments.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.8
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• pp.1915-1926
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• 1995

The Fatigue characteristics of 8-harness satin woven CFRP composites with a circular hole are experimentally investigated under constant amplitude tension-tension loading. It is found in this study that the fatigue damage accumulation behavior is very random and history-independent, and the fatigue cumulative damage is linearly related with the mean number of cycles to a specified damage state. From these results, it is known that the fatigue characteristics of CFRP composites satisfy the basic assumptions of Markov chain theory and the parameter of Markov chain model can be determined only by mean and variance of fatigue lives. The predicted distribution of the fatigue cumulative damage using Markov chain model shows a good agreement with the test results. For the fatigue life distribution, Markov chain model makes similar accuracy to 2-parameter Weibull distribution function.