• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.12
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• pp.92-100
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• 2005

An aircraft wing or fuselage panel of skin-stringer assembly can fail in a variety of instable modes under compression loads. Instability modes can be buckling of the panel, local buckling of the stringer, flexure, torsion, wrinkle and combined flexural/torsional buckling of the panel assembly. Although researches on these buckling behaviors have been carried out for a long time, there are some difficulties to apply to the practice because of complex theoretical and empirical equations. Accordingly, It is well known that leading aerospace companies are using their own in-house programs for the convenience of practical usage, but our domestic situation is that no such program has been ever developed. In this study a comprehensive program has been developed, which can identify the instability modes and the magnitude of reserve factor of the modes for the skin/stringer panel assembly under compression load. The developed program is based on the theory manual of the Airbus program APA114. For the verification, calculation of the instable reserve factors for the A320 wing panel and A380 low wing panel sections were carried out and compared with results by APA114.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.3
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• pp.46-57
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• 2006

The purpose of this study is to develop a GIS-based digital Forest Land-use(FLU) Map Building Process which will be adopted as the map publishment methodology for the official FLU Map notification in 2007. The process is composed of 6 steps, extracting forest lands from Continuous Land Map(CLM), extracting forest land borders restricted by other laws, extracting boundaries between semi- and reserve forest lands, making digital FLU map by integrating spatial and attribute data among the extractions, printing FLU map and FLU register, and re-correcting zoning errors. Through the process, in 1:25,000 and 1:5,000 scale, 14 and 173 sheets of the FLU Maps and it's register were created for the whole area of Hwaseong, Kyunggi.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.21 no.3
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• pp.196-202
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• 2018

Purpose: Treatment of chronic constipation and fecal impaction is usually outpatient and requires high or frequent doses of laxatives. However, there are children who fail outpatient treatments, sometimes repeatedly, and are ultimately hospitalized. We sought to compare the characteristics of the children who failed outpatient treatment and needed inpatient treatment vs those who achieved success with outpatient treatment, in an effort to identify attributes that might be associated with a higher likelihood towards hospitalization. Methods: In this retrospective cohort study, we reviewed the medical records of all patients aged 0 to 21 years, with chronic functional constipation and fecal impaction seen in the pediatric gastroenterology clinic over a period of 2 years. Results: Total of 188 patients met inclusion criteria. While 69.2% were successfully treated outpatient (referred to as the outpatient group), 30.9% failed outpatient treatment and were hospitalized (referred to as the inpatient group). The characteristics of the inpatient group including age at onset of $3.6{\pm}3.6years$ (p=0.02); black ethnicity (odds ratio [OR] 4.31, 95% confidence interval [95% CI] 2.04-9.09); p<0.001); prematurity (OR 2.39, 95% CI 1.09-5.26; p=0.02]; developmental delay (OR 2.20, 95% CI 1.12-4.33; p=0.02); overflow incontinence (OR 2.26, 95% CI 1.12-4.53, p=0.02); picky eating habits (OR 2.02, 95% CI 1.00-4.08; p=0.04); number of ROME III criteria met: median 4, interquartile range 3-5 (p=0.04) and $13{\pm}13.7$ constipation related prior encounters (p=0.001), were significantly different from the outpatient group. Conclusion: Identification of these characteristics may be helpful in anticipating challenges and potential barriers to effective outpatient treatment.

• Journal of Ecology and Environment
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• v.38 no.2
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• pp.241-247
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• 2015

A participatory approach of local stakeholders is important to create a balance between nature protection and the sustainable use of natural resources in a nature reserve and its vicinity area. The zoning and management policy of biosphere reserves (BRs) is a good example of this idea, especially for island reserves. Yakushima was inscribed as a World Natural Heritage (WH) in 1993. Almost all of its residents did not remember that Yakushima was a BR. In addition, Yakushima has some problems in nature reserve management. Overabundance of the deer population is a critical threat to both agriculture and natural vegetation in the world heritage site. There are too many tourists visiting the WH site and Nagata-hama beach. The beach is a Ramsar site and one of the most important spawning grounds of sea turtles in the north Pacific. Now, residents and the municipality have decided to reactivate the Yakushima BR. Although the Ministry of the Environment of Japan has an initiative to manage the WH and the Ramsar site, the BR is managed by the municipality and local stakeholders. Local activities of both nature conservation and the sustainable use of natural resources are encouraged in the BR site. The islanders willingly included all areas of the island into the BR site. Scientists who have participated in the Society of Yakushimaology have played a significant role to build trust between local stakeholders and to seek feasible policies on the nature reserves. The concept of the "Yakushima Environmental Culture Village" is a good model for the extension plan of the Yakushima and Kuchinoerabujima BRs.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.5
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• pp.413-421
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• 2001

An impaired smooth muscle cell (SMC) relaxation of coronary artery by alteration of $K^+$ channels would be the most potential explanation for reduced coronary reserve in left ventricular hypertrophy (LVH), however, this possibility has not been investigated. We performed morphometrical analysis of the coronary artery under electron microscopy and measured $Ca^{2+}-activated\;K\;(K_{Ca})$ currents and delayed rectifier K $(K_{dr})$ currents by whole-cell and inside-out patch-clamp technique in single coronary arterial SMCs from rabbits subjected to isoprenaline-induced cardiac hypertrophy. Coronary arterial SMCs underwent significant changes in ultrastructure. The unitary current amplitude and the open-state probability of $K_{Ca}$ channel were significantly reduced in hypertrophy without open-time and closed-time kinetic. The concentration-response curve of $K_{Ca}$ channel to $Ca^{2+}$ is shifted to the right in hypertrophy. The reduction in the mean single channel current and increase in the open channel noise of $K_{Ca}$ channel by TEA were more sensitive in hypertrophy. $K_{dr}$ current density is significantly reduced in hypertrophy without activation and inactivation kinetics. The sensitivity of $K_{dr}$ current on 4-AP is significantly increased in hypertrophy. This is the first study to report evidence for alterations of $K_{Ca}$ channels and $K_{dr}$ channels in coronary SMCs with LVH. The findings may provide some insight into mechanism of the reduced coronary reserve in LVH.

• The Journal of the Korea Contents Association
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• v.15 no.11
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• pp.359-373
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• 2015

Cognitive reserve(CR) is the ability to optimize or maximize performance through complementary brain networks. CR is relevant to normal aging in cognitive-linguistic abilities. There are few domestic systematic reviews or meta-analyses that analyze the relationships between multiple CR and cognitive-linguistic domains in healthy older people. This meta-analysis included 32 studies published since 2000. In result, education level topped the list, followed by the occupation, cognitively stimulating activities, and the multilingualism. Most studies were related to memory, global cognition, and language. CR had a modest positive association with cognitive-linguistic performance. Multiple domains including memory and language also showed the significant correlations across most measures of CR. This study provides evidence-based information to support cognitive-linguistic ability in normal aging.

• Transactions on Electrical and Electronic Materials
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• v.6 no.6
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• pp.245-248
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• 2005

The physical and electrical properties of polycrystalline $\beta$-SiC were studied according to different nitrogen doping concentration. Nitrogen-doped SiC films were deposited by LPCVD(1ow pressure chemical vapor deposition) at $900^{\circ}C$ and 2 torr using $100\%\;H_2SiCl_2$ (35 sccm) and $5 \%\;C_2H_2$ in $H_2$(180 sccm) as the Si and C precursors, and $1\%\;NH_3$ in $H_2$(20-100 sccm) as the dopant source gas. The resistivity of SiC films decreased from $1.466{\Omega}{\cdot}cm$ with $NH_3$ of 20 sccm to $0.0358{\Omega}{\cdot}cm$ with 100 sccm. The surface roughness and crystalline structure of $\beta$-SiC did not depend upon the dopant concentration. The average surface roughness for each sample 19-21 nm and the average surface grain size is 165 nm. The peaks of SiC(111), SiC(220), SiC(311) and SiC(222) appeared in polycrystalline $\beta$-SiC films deposited on $Si/SiO_2$ substrate in XRD(X-ray diffraction) analysis. Resistance of nitrogen-doped SiC films decreased with increasing temperature. The variation of resistance ratio is much bigger in low doping, but the linearity of temperature dependent resistance variation is better in high doping. In case of SiC films deposited with 20 sccm and 100 sccm of $1\%\;NH_3$, the average of TCR(temperature coefficient of resistance) is -3456.1 ppm/$^{\circ}C$ and -1171.5 ppm/$^{\circ}C$, respectively.

• Journal of Haehwa Medicine
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• v.15 no.2
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• pp.263-272
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• 2006

Purpose Brain vessles have autoregulation function, so even when perfusion pressure drops, cerebral blood flow remain stable by vasodilation. Latest research on this reserve of cerebral vessels is being done using TCD, which measures the reserve of the vessels. We did a research comparing cerebral vessel and peripheral vessel reserve between Taeumin, who are more likely to suffer CVA, and the normal. We observed blood flow of Internal carotid artery siphon and radial indicis artery of the two group with TCD. Method We picked 20 people out of patients diagnosed as cerebral infarction at Cheon-An Oriental hospital of Daejeon University. They were diagnosed as Taeumin with QSCCII questionnaire and constitutional differentiation. Using TCD, we measured highest blood flow rate, mean blood flow and asymmetric counting blood flow of Internal carotid artery siphon and radial indicis artery at rest. And then we measured again after stimulating cerebral vessels, by triggering hypercapnia by self apnea and peripheral vessels by palm heating. Result At rest, mean blood flow rate of Internal carotid artery siphon showed significant decrease compared to control group. Blood flow rate of Internal carotid artery siphon after hypercapnia showed significant decline in highest blood flow rate and mean blood flow compared to control group. Cerebral vessel reaction after the hypercapnia induction showed great change in experiment group than the control group. Peripheral vessel reaction after palm heating showed significant decline in experiment group compared to control group. Conclusion In conclusion, measuring the alteration of blood flow used in diagnosing cerebral infarction, is more sensitive when vessel stimulation is done. Non-invasive TCD is effective especially in case of Taeumin who are more likely to suffer vascular disorder than others.

• Journal of Korean Society of societal Security
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• v.1 no.1
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• pp.45-51
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• 2008

The purpose of this study is to suggest some effective ways to implement the regeneration projects for the zones vulnerable to natural disasters which have been delayed due to shortage of the financial resources, and thereby complete the disaster prevention projects as early as possible and thus secure the financial resources for the projects continuously. For this purpose, the researcher reviewed the statutory grounds and designation procedures or the zones vulnerable to natural disasters, and thereupon, examined and analyzed the regeneration projects being implemented in Gyeonggi-do in view of contents by zone, history of damages, annual investment plans and financial resources for investments. In addition, the researcher examined the criteria for reserve of the disaster management fund and its uses and investigated the fund sources and expenditures and thereby, addressed the problems of the statutory reserve and suggested their solutions. All in all, the researcher suggested that the disaster management fund should be invested in regeneration projects for the zones vulnerable to natural disasters in order to remove the disaster risks earlier and that the uses of the fund should be adequately deregulated with a reserve fund ceiling system to secure the financial resources for the disaster prevention projects continuously.

• Journal of the Korean Data and Information Science Society
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• v.28 no.2
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• pp.271-286
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• 2017

The objective of this paper is to evaluate whether longevity risk is properly managed in Korean life insurance industry by measuring longevity risk in the viewpoint of natural hedge. According to analysis, the sum of the reserve of annuity and that of whole life insurance appears to decrease in the case both reserve of annuity and whole life insurance are shocked by same degree and also the mortality rate of the aged policyholders is improved faster than that of the less aged policyholders. Although the sum of the reserves increases only when the mortality improvement of annuity policyholders is higher than that of whole life insurance policyholders by two times, more than 60% of reserve increase of annuity is found to be offset by natural hedge. Thus, it is judged that the longevity risk of Korea life insurance industry is properly managed by natural hedge.