• Economic and Environmental Geology
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• v.39 no.4 s.179
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• pp.369-384
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• 2006

Korean Peninsula, located on the southeastern part of Eurasian plate, belongs to the intraplate region. The characteristics of intraplate earthquake show the low and rare seismicity and the sparse and irregular distribution of epicenters comparing to interplate earthquake. To evaluate the exact seismic activity in intraplate region, long-term seismic data including historical earthquake data should be archived. Fortunately the long-term historical earthquake records about 2,000 years are available in Korea Peninsula. By the analysis of this historical and instrumental earthquake data, seismic activity was very high in 16-18 centuries and is more active at the Yellow sea area than East sea area. Comparing to the high seismic activity of the north-eastern China in 16-18 centuries, it is inferred that seismic activity in two regions shows close relationship. Also general trend of epicenter distribution shows the SE-NW direction. In Korea Peninsula, the first seismic station was installed at Incheon in 1905 and 5 additional seismic stations were installed till 1943. There was no seismic station from 1945 to 1962, but a World Wide Standardized Seismograph was installed at Seoul in 1963. In 1990, Korean Meteorological Adminstration(KMA) had established centralized modem seismic network in real-time, consisted of 12 stations. After that time, many institutes tried to expand their own seismic networks in Korea Peninsula. Now KMA operates 35 velocity-type seismic stations and 75 accelerometers and Korea Institute of Geoscience and Mineral Resources operates 32 and 16 stations, respectively. Korea Institute of Nuclear Safety and Korea Electric Power Research Institute operate 4 and 13 stations, consisted of velocity-type and accelerometer. In and around the Korean Peninsula, 27 intraplate earthquake mechanisms since 1936 were analyzed to understand the regional stress orientation and tectonics. These earthquakes are largest ones in this century and may represent the characteristics of earthquake in this region. Focal mechanism of these earthquakes show predominant strike-slip faulting with small amount of thrust components. The average P-axis is almost horizontal ENE-WSW. In north-eastern China, strike-slip faulting is dominant and nearly horizontal average P-axis in ENE-WSW is very similar with the Korean Peninsula. On the other hand, in the eastern part of East Sea, thrust faulting is dominant and average P-axis is horizontal with ESE-WNW. This indicate that not only the subducting Pacific Plate in east but also the indenting Indian Plate controls earthquake mechanism in the far east of the Eurasian Plate. Crustal velocity model is very important to determine the hypocenters of the local earthquakes. But the crust model in and around Korean Peninsula is not clear till now, because the sufficient seismic data could not accumulated. To solve this problem, reflection and refraction seismic survey and seismic wave analysis method were simultaneously applied to two long cross-section traversing the southern Korean Peninsula since 2002. This survey should be continuously conducted.

• Journal of Intelligence and Information Systems
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• v.20 no.3
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• pp.19-43
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• 2014

The Pareto principle, also known as the 80-20 rule, states that roughly 80% of the effects come from 20% of the causes for many events including natural phenomena. It has been recognized as a golden rule in business with a wide application of such discovery like 20 percent of customers resulting in 80 percent of total sales. On the other hand, the Long Tail theory, pointing out that "the trivial many" produces more value than "the vital few," has gained popularity in recent times with a tremendous reduction of distribution and inventory costs through the development of ICT(Information and Communication Technology). This study started with a view to illuminating how these two primary business paradigms-Pareto principle and Long Tail theory-relates to the success of virtual knowledge collaboration. The importance of virtual knowledge collaboration is soaring in this era of globalization and virtualization transcending geographical and temporal constraints. Many previous studies on knowledge sharing have focused on the factors to affect knowledge sharing, seeking to boost individual knowledge sharing and resolve the social dilemma caused from the fact that rational individuals are likely to rather consume than contribute knowledge. Knowledge collaboration can be defined as the creation of knowledge by not only sharing knowledge, but also by transforming and integrating such knowledge. In this perspective of knowledge collaboration, the relative distribution of knowledge sharing among participants can count as much as the absolute amounts of individual knowledge sharing. In particular, whether the more contribution of the upper 20 percent of participants in knowledge sharing will enhance the efficiency of overall knowledge collaboration is an issue of interest. This study deals with the effect of this sort of knowledge sharing distribution on the efficiency of knowledge collaboration and is extended to reflect the work characteristics. All analyses were conducted based on actual data instead of self-reported questionnaire surveys. More specifically, we analyzed the collaborative behaviors of editors of 2,978 English Wikipedia featured articles, which are the best quality grade of articles in English Wikipedia. We adopted Pareto ratio, the ratio of the number of knowledge contribution of the upper 20 percent of participants to the total number of knowledge contribution made by the total participants of an article group, to examine the effect of Pareto principle. In addition, Gini coefficient, which represents the inequality of income among a group of people, was applied to reveal the effect of inequality of knowledge contribution. Hypotheses were set up based on the assumption that the higher ratio of knowledge contribution by more highly motivated participants will lead to the higher collaboration efficiency, but if the ratio gets too high, the collaboration efficiency will be exacerbated because overall informational diversity is threatened and knowledge contribution of less motivated participants is intimidated. Cox regression models were formulated for each of the focal variables-Pareto ratio and Gini coefficient-with seven control variables such as the number of editors involved in an article, the average time length between successive edits of an article, the number of sections a featured article has, etc. The dependent variable of the Cox models is the time spent from article initiation to promotion to the featured article level, indicating the efficiency of knowledge collaboration. To examine whether the effects of the focal variables vary depending on the characteristics of a group task, we classified 2,978 featured articles into two categories: Academic and Non-academic. Academic articles refer to at least one paper published at an SCI, SSCI, A&HCI, or SCIE journal. We assumed that academic articles are more complex, entail more information processing and problem solving, and thus require more skill variety and expertise. The analysis results indicate the followings; First, Pareto ratio and inequality of knowledge sharing relates in a curvilinear fashion to the collaboration efficiency in an online community, promoting it to an optimal point and undermining it thereafter. Second, the curvilinear effect of Pareto ratio and inequality of knowledge sharing on the collaboration efficiency is more sensitive with a more academic task in an online community.

• Journal of the Korean Geographical Society
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• v.49 no.5
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• pp.656-674
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• 2014

The objective of this study was to examine the distinctiveness and generality of landforms of the Korean peninsula, and further discover geomorphological principle that can be applied to land and environmental management in Korea. The research targeted East Asia and Korea, with terrain analysis conducted at a continental scale, national scale, and regional scale sequentially. East Asia displays complicated characteristics and evolutionary history of geotectonics, but exhibits distinct northeast-southwest geomorphological structure and connectivity at the continental level. While the Korean peninsula follows this pattern on a continental scale, it also features NNW-SSE direction (Nangrim and Taebaek Mountains) geomorphological connectivity that intersects at a right angle. From a national perspective, the Korean peninsula hosts the most diverse geomorphological features within East Asia. It does not have a high average altitude, but has relatively high slope angle and intricate topographical distribution in comparison to neighboring areas. While the mountains and plains of the Korean peninsula display a smooth connection, geomorphologically similar areas such as Shikhote-Alin, Huanan in China, and Japan have clear characteristics that divide the mountains and plains. Despite the distinctiveness and diversity that appear in East Asian topography on the regional scale, the connectivity that links the top of mountain (hill) to stream is identical among all areas as a general rule. It is collectively considering the connectivity and the geomorphological and ecological processes that arise within this connectivity that will serve as the focal point for sustainable landscape management.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.3
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• pp.302-309
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• 2008

Epigenetic is usually referring to heritable traits that do not involve changes to the underlying DNA sequence. DNA methylation is known to serve as cellular memory. and is one of the most important mechanism of epigenetic. DNA methylation is a covalent modification in which the target molecules for methylation in mammalian DNA are cytosine bases in CpG dinucleotides. The 5' position of cytosine is methylated in a reaction catalyzed by DNA methyltransferases; DNMTl, DNMT3a, and DNMT3b. There are two different regions in the context of DNA methylation: CpG poor regions and CpG islands. The intergenic and the intronic region is considered to be CpG poor, and CpG islands are discrete CpG-rich regions which are often found in promoter regions. Normally, CpG poor regions are usually methylated whereas CpG islands are generally hypomethylated. DNA methylation is involved in various biological processes such as tissue-specific gene expression, genomic imprinting, and X chromosome inactivation. In general. cancer cells are characterized by global genomic hypomethylation and focal hypermethylation of CpG islands, which are generally unmethylated in normal cells. Gene silencing by CpG hypermethylation at the promotors of tumor suppressor genes is probably the most common mechanism of tumor suppressor inactivation in cancer.

• Journal of Korean Academy of Nursing Administration
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• v.1 no.2
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• pp.338-348
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• 1995

We need to continuously evaluate for nursing quality and the outcome to reflect nursing, to repair and improve of nursing. The first problem for nursing quality improvement is development of evaluation tool for the quality of nursing care. We need a system for quality assurance evaluation that is, development and framework of evaluation tool for nursing care quality. The purpose of this study was attempted to develop an evaluation tool for the quality of nursing care in musculoskeletal disorder patients. The approach method of nursing quality for the development of the tool in this study was process evaluation framework. The study were devided dvelopment process and reliability, validity verification process. The subjects of development process of this tool are three nursing export groups, and the subject of reliability, validity verification process are 20 samples of two university hospital in seoul, who were within discharge 3 months after admission treatment in musculo-skeletal disorder. Data for this study was collected from March 10 to April 13, 1995. The development process of the tool were as follows : 1. Make preliminary list of the tool by focal group were constituted 12 clinical nurses. 2. Modify and add preliminary list by 4 nursing expert panel. 3. Calculate content validity of the tool by 25 nursing expert panel of judge. 4. Verify reliability and validity of the tool. 5. Finalize an evaluation tool for the quality of the nursing care in musculo-skeletal disorder. The results of this study were as follows : 1) Development an evaluation tool for the quality of nursing care in musculo-skeletal disorder. (1) The evalution tool of this study was developed 5 standards, 33 criterias and 133 indicators. (2) 5 standards were divided according to Nursing Process. from standard 1 to standard 5, involved criterias were each 6(18%), 3(9%), 3(9%), 15(46%), 6(18%). 2) Verify reliability and validity of the tool. (1) Score of adequate degree for content validity of 33 criterias and 133 indicators were every average 2.82. (2) Inter-rater reliabilities(consentaneity score) of the tool by pearson correlation coefficient between three raters were : r=.7506, r=.8934, r=.6695. and Inter-rater reliabilities by single-facet crossed design were : r=.7464. (3) The alpha coefficient relating to internal consistency was .8524 over all 30 items of 33 criterias of developed tool. (4) Score of the quality of nursing care following to generaal characteristics of this study subjects were stastically significant differences according to educational level (F=2.93, p=.029)and diagnosing classification (F=2.50, p=.042). Through this study, I'm sure that the developed tool for the quality of patient care in musculo-skeletal disorder will show the way of more improvement of the quality of nursing care and effective nursing interventions.

• International Journal of Oral Biology
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• v.32 no.1
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• pp.35-43
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• 2007

Tooth loss in elderly is mainly caused by alveolar bone loss via severe periodontitis. Although the severity of periodontitis is known to be affected by age, the aging process or the genetic changes during the aging of periodontal tissue cells are not well characterized. In this study, we investigated the effect of in vitro aging on the change of gene expression pattern in periodontal fibroblasts. Gingival fibroblasts (GF) and periodontal ligament fibroblasts (PDL) were obtained from two young patients and replicative senescence was induced by sequential subcultivation. When more than 90% cells were positively stained with senescence-associated ${\beta},-galactosidase$, those cells were regarded as aged cells. In aged GF and PDL, the level of phosphorylated retinoblastoma (RB) and $p16^{INK4A}$ protein was significantly decreased and increased, respectively. However, the protein level of p53 and p21, well known senescence-inducing genes, did not increase in aged GF and PDL. Although $p27^{Kip1}$ and $p15^{INK4B}$, another cyclin-dependent kinase inhibitors, were reported to be involved in replicative senescence of human cells, they were decreased in aged GF and PDL. Because senescent cells showed flattened and enlarged cell shape and are known to have increased focal adhesion, we examined the protein level of several integrins. Aged GF and PDL showed increased protein level of integrin ${\alpha}2$, ${\alpha}v$, and ${\beta}1$. When the gene expression profiles of actively proliferating young cells and aged cells were compared by cDNA microarray of 3,063 genes and were confirmed by reverse transcription-polymerase chain reaction, 7 genes and 15 genes were significantly and commonly increased and decreased, respectively, in aged GF and PDL. Among them, included are the genes that were known to be involved in the regulation of cell cycle, gene transcription, or integrin signaling. The change of gene expression pattern in GF and PDL was minimally similar to that of oral keratinocyte. These results suggest that $p16^{INK4A}/RB$ might be involved in replicative senescence of periodontal fibroblasts and the change of gene expression profile during aging process is cell type specific.

• Journal of Yeungnam Medical Science
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• v.22 no.1
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• pp.81-89
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• 2005

Background: Hysteroscopy is considered to be the gold standard not only for visualizing the cervical canal and the uterine cavity, but also for treating many different types of benign pathologies localized to those regions. The advent and evolution of endoscopic imaging and surgery during the last two decades has added new dimensions to the armamentarium of a gynecologist to combat intrauterine lesions. Office hysteroscopy is increasingly being used as a first line investigation for abnormal uterine bleeding and other diseases involving the uterine cavity. The aim of our study is to assess the diagnostic and operative efficacy of office hysteroscopy. Materials and Methods: In our department, 140 patients underwent a hysteroscopy examination and 18 of these underwent an office based hysteroscopy examination from September 1995 to March 2005. The cases who underwent an office based hysteroscopy examination were reviewed in order to assess the clinical usefulness and significance in the management of intrauterine lesions. Results: Major indication was abnormal uterine bleeding(12 cases, 66.7%). The others were a missed IUD and infertility. The hysteroscopic findings were a normal uterine cavity(6 cases, 33.3%), IUD in situ, polyp, submucosal myoma, endometrial hyperplasia and a placenta remnant. Conclusion: Office hysteroscopy is a safe, quick and effective method for making an intrauterine evaluation. In addition, it provides immediate results, offers the capacity of direct targeted biopsies of suspicious focal lesions, and offers the direct treatment of some intrauterine conditions.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.9
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• pp.3939-3944
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• 2014

Background: To elucidate the role of rapamycin and PF4 on apoptosis regulation via Bax (pro-apoptosis), Bcl-2 (anti-apoptosis) and survivin activation on the growth in the 1-methyl-1-nitrosourea-induced invasive breast carcinoma model. Materials and Methods: Thirty five female Sprague Dawley rats at age 21-day old were divided into 4 groups; Group 1 (control, n=10), Group 2 (PF4, n=5), Group 3 (rapamycin, n=10) and Group 4 (rapamycin+PF4, n=10). MNU was administered intraperitionally, dosed at 70mg/kg body weight. The rats were treated when the tumors reached the size of $14.5{\pm}0.5mm$ and subsequently sacrificed after 5 days. Rapamycin and PF4 were administered as focal intralesional injections at the dose of $20{\mu}g$/lesion. The tumor tissue was then subjected to histopathological examinations for morphological appraisal and immunohistochemical assessment of the pro-apoptotic marker, Bax and anti-apoptotic markers, Bcl-2 and survivin. Results: The histopathological pattern of the untreated control cohort showed that the severity of the malignancy augments with mammary tumor growth. Tumors developing in untreated groups were more aggressive whilst those in treated groups demonstrated a transformation to a less aggressive subtype. Combined treatment resulted in a significant reduction of tumor size without phenotypic changes. Bax, the pro-apoptotic marker, was significantly expressed at higher levels in the rapamycin-treated and rapamycin+PF4-treated groups compared to controls (p<0.05). Consequently, survivin was also significantly downregulated in the rapamycin-treated and rapamycin+PF4-treated group and this was significantly different when compared to controls (p). Conclusions: In our rat model, it could be clearly shown that rapamycin specifically affects Bax and survivin signaling pathways in activation of apoptosis. We conclude that rapamycin plays a critical role in the induction of apoptosis in MNU-induced mammary carcinoma.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.5
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• pp.707-712
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• 2011

The objective of the present study was to determine gender-related and month-related behavioral differences in captive alpine musk deer. The study was conducted at Xinglongshan Musk Deer Farm (XMDF) of Xinglongshan National Nature Reserve in Gansu Province of western China. The integrated method of focal sampling and all occurrence recording was utilized to quantify the behavioural patterns of 45 captive alpine musk deer (Moschus sifanicus) during non-mating season (from August $1^{st}$ to October $25^{th}$), and the behavioural durations of 12 behavioural patterns such as standing-gazing were recorded. The behavioural modes were compared to explore the potential differences between females and males, and the monthly behavioural modes for males and females were analyzed. Our results showed that the captive female deer in XMDF could compensate the energy lost in pregnancy, parturition and lactation through improving its ingestive efficiency. In order to be more sensitive to the changing environment, females expressed more standing-gazing (SG: $67.38{\pm}12.69\;s$) and moving (MO; $27.41{\pm}5.02\;s$), but less bedding (BE: $42.32{\pm}11.35\;s$) than male deer (SG: $56.43{\pm}9.19\;s$; MO: $19.23{\pm}4.64\;s$; BE: $96.14{\pm}15.71\;s$). Furthermore, females perform more affinitive interaction (AI: $7.89{\pm}4.81\;s$) but less ano-genital sniffing (AS: $0.24{\pm}0.13\;s$) and agonistic behaviour (CI: $0.57{\pm}0.26\;s$) than males (AI: $1.45{\pm}1.09\;s$; AS: $0.45{\pm}0.29\;s$; CI: $1.42{\pm}0.67\;s$). The females expressed ingestion more in October ($132.31{\pm}27.47\;s$) than in August ($28.80{\pm}18.44\;s$) and September ($45.1{\pm}10.84\;s$), and the males performed Ano-genital sniffing (AS: $1.79{\pm}1.14\;s$) and self-directed behaviour (SD: $12.61{\pm}5.03\;s$) significantly more in October than in August (AS: 0 s; SD: $0.62{\pm}0.17\;s$) and September (AS: $0.02{\pm}0.01\;s$; SD: $0.17{\pm}0.15\;s$). Moreover, male musk deer increased the intension of ano-genital sniffing, agonistic behaviour and tail rubbing behaviour, which were related to sexual activities.

• Journal of Gastric Cancer
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• v.20 no.2
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• pp.165-175
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• 2020

Purpose: The guidelines for pathological evaluation of early gastric cancer (EGC) recommend wider section intervals for surgical specimens (5-7 mm) than those for endoscopically resected specimens (2-3 mm). Studies in surgically resected EGC specimens showed not negligible lymph node metastasis risks in EGCs meeting the expanded criteria for endoscopic submucosal dissection (ESD). Materials and Methods: This retrospective study included 401 EGC lesions with an endoscopic size of ≤ 30 mm detected in 386 patients. Pathological specimens obtained by ESD or surgery were cut into 2-mm section intervals for reference. Submucosal or lymphovascular invasion (LVI) was evaluated arbitrarily in 4- or 6-mm section intervals. McNemar's tests compared the differences between submucosal and LVI. Results: Submucosal invasion was detected in 29.2% (117/401) and LVI in 9.5% (38/401) at 2-mm interval. The submucosal invasion detection rates in 4-mm intervals decreased to 88.0% or 90.6% (both P<0.001), while the LVI detection rates decreased to 86.8% or 57.9% (P=0.025 and P<0.001, respectively). In 6-mm intervals, the submucosal and LVI detection rates decreased further to 72.7-80.3% (P<0.001 for all three sets) and 55.3-63.2% (P<0.001 for all three sets), respectively. Among 150 out-of-indication cases at 2-mm interval, 4-10 (2.7%-6.7%) at 4-mm intervals, and 10-17 (6.7%-11.3%) at 6-mm intervals were misclassified as lesions meeting the curative resection criteria due to the underestimation of submucosal or LVI. Conclusions: After ESD, the 2-mm wide section interval was suitable for the pathological evaluation of focal submucosal or LVI. Thus, if an EGC lesion meets the expanded criteria for the ESD specimen pathological evaluation, it could be safely followed up.