• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.6
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• pp.485-492
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• 2014

In regards to natural disasters, vulnerability analysis is a component of the disaster risk analysis with one of its objectives as a basis for planning priority setting activities. The volcano eruption raises many casualties and property in the surrounding area, especially when the volcano located in densely populated areas. Volcanic eruptions cannot be prevented, but the risk and vulnerability can be reduced which involve careful planning and preparations that anticipate a future crisis. The social vulnerability as social inequalities with those social factors can influence the susceptibility of various groups to harm and govern their ability to respond. This study carried out the methods of Social Vulnerability Index (SoVI) to measure the socially created vulnerability of the people living in Merapi proximal hamlets in Central Java, Indonesia that refers to the socioeconomic and demographic factors that affect the resilience of communities in order to describe and understand the social burdens of risk. Social vulnerability captured here, using a qualitative survey based-data such as interviews to local people with random ages and background to capture the answer vary, also interviews to stakeholders to help define social vulnerability variables. The paper concludes that by constructing the vulnerability index for the hamlets, the study reveals information about the distribution and causes of social vulnerability. The analysis using SoVI confirms that this method works well in ensuring that positive values indicating high social vulnerability and vice versa.

• The KIPS Transactions:PartD
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• v.16D no.5
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• pp.661-672
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• 2009

Recently it was found that various genetic structural variations such as CNV(copy number variation) exist in the human genome, and these variations are closely related with disease susceptibility, reaction to treatment, and genetic characteristics. In this paper we propose a new CNV detection algorithm using millions of short DNA sequences generated by giga-sequencing technology. Our method maps the DNA sequences onto the reference sequence, and obtains the occurrence frequency of each read in the reference sequence. And then it detects the statistically significant regions which are longer than 1Kbp as the candidate CNV regions by analyzing the distribution of the occurrence frequency. To select a proper read alignment method, several methods are employed in our algorithm, and the performances are compared. To verify the superiority of our approach, we performed extensive experiments. The result of simulation experiments (using a reference sequence, build 35 of NCBI) revealed that our approach successfully finds all the CNV regions that have various shapes and arbitrary length (small, intermediate, or large size).

• Pediatric Infection and Vaccine
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• v.13 no.1
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• pp.63-70
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• 2006

Purpose : We hypothesized that mannose binding lectin gene(MBL2), a key molecule of innate immunity, may contirbute to the development and the outcome of respiratory syncytial virus(RSV) disease in early childhood. This study was performed to investigate the genetic basis of polymorphisms and haplotypes of MBL2 for RSV disease severity in Korean children. Methods : Cases with severe RSV diseases are 99 children with severe RSV lower respiratory tract infections, who were admitted to the Seoul National University Children's Hospital through 1993~2000. The control subjects consisted of 224 anonymous healthy Korean blood donors. The frequency of promoter variant(-221, X/Y) and structural variant(codon 54) were compared between the case patient group and the control subject group. Results : The mean age of patients was 11.8 months; 49% were <6 months, 39% were 6-24 months and 12% were >24 months. In the cohort of cases of severe RSV diseases, the genotypic frequencies of structural variant in codon 54 were 61% for AA, 34% for AB, and 5% for BB. Those of the promoter X/Y variant were 85% for YY and 15% for XY. There were no significant differences in overall distribution of both structural and promoter variants between the cases and the control subjects. We did not observe statistical difference in the haplotypic frequencies of MBL2. Conclusion : Common variants of MBL2 gene most likely do not contribute to the risk for severe RSV diseases in Korean children. Further genetic association studies should be conducted in a larger propsectively recruited cohort of children with RSV infection.

• Journal of Food Hygiene and Safety
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• v.33 no.4
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• pp.259-265
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• 2018

Since Korean housewives are responsible for the dietary practices of family at home, it is important to know what information will make them to buy safe food. This study was designed to determine the role of perceived threats, behavioral assessments, and self-efficacy factors known to promote healthy behavior in health belief models (HBM) based on food safety awareness and behavior of housewives. This study involved 191 housewives, based on key variables such as perceived severity, perceived susceptibility, perceived benefits, perceived barriers, self-efficacy, and purchase behavior. The results showed that higher levels of education and urbanization increased the threat perception and the likelihood of buying safe food. The correlation analysis showed that increased awareness and knowledge of safe foods and interest in health contributed to higher relative benefit or self-efficiency of food, and thus, ensured food safety. The conceptual model of food safety behavior based on the HBM was verified via structural equation analysis. The findings suggest that a suitable model showcasing knowledge levels and relative benefits resulted in a greater impact on purchasing behavior than perceived threats. This study suggests that it is more effective for housewives to provide more preventive information than risk information to purchase safe food.

• Journal of Korean Academy of Nursing
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• v.10 no.2
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• pp.73-85
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• 1980

The purpose of this study was to investigate the compliance behavior of hypertensive patients in light of their health belief model that explains an individual's compliance with health maintenance or getting well. Although there are many effective regimens and treatments for hypertension nowadays. the most important point to be taken to consideration in their behavioral aspect is their compliance with regard to the control of body weight. eating habits as to salt and cholesterol intake. stresses. activity patterns and smoking as related to their life style. The important reasons for the failure in the control of hypertensive patients are the complexity of regimens to be complied to. irregular medication and the life long restrictions in their own life style. The compliance of patients to medical regimens and rocommendations or failure to do so is an essential factor. Accordingly. the degree of the patient's compliance is an important determinant as to the success or failure of hypertension control. The subjects for this study were 187 hypertensive patients selected from admitted and out patients of the medical department at seven University Hospitals in Seoul. Data was collected from Dec. 1, 1979 to Feb. 15, 1980 using the questionaire method and was analysed by the use of means. standard deviations, coefficient of correlations, analysis of variance and multiple regression analysis. The results obtained are as follows A. Of the seven independent variables in light of health belief model. benefit. barrier and severity are closely related to patient's compliance behavior. Therefore these variables could be used as determinants to predict and modify the hypertensive behavior. 1. Benefit is the most important and significant of the variables for explaining the dependent variables. It accounts for the highest variance of patient's compliance. (23.62%) 2. Then taking the former together with barrier. the variance of compliance showed on increase. (26.59%) 3. And with the addition of severity to the first two. the variance of compliance was also increased. (28.l2 %) B. Except for susceptibility all the independent variables such as severity. benefit, knowledge. motivation and barrier are correlated to dependent variable compliance. C. Sex. marital status and religion appeared to have significant influence on the dependent variables. Therefore one could conclude that the more the patients are aware that hypertension is a threat to health. the more they understand the benefit of taking actions to prevent such a threat. and the less they perceive any barrier when taking action. the more compliant they become in following medical regimens and recommendations. Age. marital status and religion played a significant influence to their compliance. Accordingly. the selected structural variables and demographic variables which have influenced sick role behavior of the hypertensive patient must be integrated to teaching and counselling programs for better hypertension control.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.235-243
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• 2002

Ni-base superalloys are used extensively in industry, both in aeroengines and land based turbines. About 60% by weight of most modern gas turbine engine structural components are made of Ni-base superalloys. To satisfy practical demands, the efficiency of gas turbine engines has been steadily and systematically increased by design modifications to handle higher turbine inlet or firing temperatures. However, the increase in operating temperatures has lead to a decrease in the life of components and increase in costs of replacement. Moreover, around 80% of the large frame size industrial/utility gas turbines operating in the world today were installed in the mid-sixties to early seventies and are now 25 to 30 years old. Consequently, there are greater opportunities now to repair and refurbish the older models. Basically, there are two major factors influencing the weldability of the cast alloys: strain-age cracking and liquation cracking. Susceptibility to strain-age cracking is due to the total Ti plus AI content of the alloy; Liquation cracking is due either to the presence of low melting constituents or constitutional liquation of constituents. Though Rene 41 superalloy has 4.5wt.% total Ti and Al content and falls just below the safe limit proposed by Prager et al., controlled grain size and special heat treatments are needed to obtain crack-free welds. Varying heat treatments and filler materials were used in a laboratory study, then the actual welding of service parts was carried out to verity the possibility of crack-tree weld of components fabricated from Rene 41 superalloy. The microstructural observations indicated that there were two kinds of carbides in the FCC matrix. MC carbides were located along the grain boundaries, while M$_{23}$C$_{6}$ carbide was located both inter and intra granularly. Two kinds of filler materials, Rene 41 and Hastelloy X were used to gas tungsten arc weld a patch into the sheet metal, along with varying pre-weld heat treatments. The microstructure, hardness and tensile tests were determined. The service distressed parts were categorized into three classes: with large cracks, with medium cracks and with small or no visible cracks. No significant difference in microstructure among the specimens was observed. Specimens were cut from the corner and the straight edge of the patch repair, away from the corner. The only cracks present were found to be associated with inadequate surface preparation to remove oxidation. Guidelines for oxide removal and the welding procedures developed in the research enabled crack-free welds to be produced.d.

• Journal of Life Science
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• v.14 no.1
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• pp.180-187
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• 2004

Crowing evidence indicates that oxidized low density lipoprotein (LDL) nay promote atherogenesis. Therefore, inhibition of LDL oxidation may impede this process. The effect of geraniin on the susceptibility of human low density lipoprotein (LDL) to macrophages-induced oxidation was investigated by monitoring a thiobarbiruric acid reactive substrance (TBARS). The antioxidative activity of geraniin was higher than that of $\alpha$-tocopherol on low density lipoprotein (LDL) oxidation by thiobarbituric acid reactive substance (TBARS). Geraniin inhibited the C $u^{2+}$ mediated oxidation of human LDL in a dose dependent manner at concentration of 50 and 100 $\mu\textrm{g}$/mL. Geraniin, almost completely inhibited the macrophages mediated LDL oxidation in electrophoretic mobility and conjugate diene of LDL oxidation. Also, geraniin almost completely inhibited 0$_2$$^{[-10]}$ at concentration of 100 $\mu\textrm{g}$/mL. The physiological relevance of the antioxidative activity was validated at the cellular level where geraniin inhibited endothelial cell mediated LDL oxidation, When compound with several other antioxidants geraniin showed a high activity equal to natural antioxidants, $\alpha$-tocopherol and ascorbic acid, and the synthetic antioxidant, protocol. These results indicate that geraniin might play a protective antioxidant effects on LDL, probably affecting both the structural properties of macrophage and endothelial cell for the LDL oxidation..

• Korean Journal of Heritage: History & Science
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• v.46 no.3
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• pp.48-67
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• 2013

This study was focused on the recognition of historical values and the establishment of conservation schemes for a Silla stone monument in Bongpyeong-ri, Uljin by combining the humanistic investigation of inscription reinterpretation and the scientific conservational diagnosis of deterioration. According to the investigation of inscription, a total of 13 letters were reconsidered compared to the preceding researches. Thus, the meaning and interpretation of previous inscription was partially changed. This monument is composed of gneissose leucogranite and the most suitable site as provenance of the stone would be the Jukbyeon seashore (2.1km). The site shows similar color, size and composition of minerals, gneissose structure and magnetic susceptibility as the Bongpyeong stone monument. This monument developed a structural crack (crack index 0.4) and a microcrack (crack index 2.0) along the gneissose structure. The horizontal strength is weaker than the vertical strength. Therefore, the cracks should be reinforced and treated. However, consolidating is not urgently needed because the total weathering grade by ultrasonic velocity shows the stage of moderate weathering(3,403m/s, 0.32). Also, the major problems of chemical deterioration are blackening (85.2%) with soil, iron oxide,rubbing mark, and salt crystals (17.3%) from the sea. Therefore, the contaminants and the salt crystals should be removed using pressure spray and pulp paper, while the application of poultice should be examined through clinical tests.

• Journal of the Korean Chemical Society
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• v.66 no.6
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• pp.451-458
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• 2022

Through the crystal alignment research based on the magnetic properties of LiNi_xMn_yCo_1-(x+y)O₂ such as magnetic susceptibility and related anisotropy, a crystal aligned LiNi_0.6Mn_0.2Co_0.2O₂ electrode is obtained, in which the (00l) plane is frequently oriented perpendicular to the surface of a current collector. The crystal aligned LiNi_0.6Mn_0.2Co_0.2O₂ electrode steadily exhibits low electrode polarization properties during the charge/discharge process in a lithium-ion battery, thus affording an improved capacity compared to a pristine LiNi_0.6Mn_0.2Co_0.2O₂ electrode. The aligned LiNi_0.6Mn_0.2Co_0.2O₂ electrode may have an appropriate structural nature for fast lithium-ion transport due to the oriented (00l) plane, and thus it contributes to enhancing the battery performance. This enhancement is analyzed in terms of various electrochemical theories and experiment results; thus, it is verified to occur because of the considerably fast lithium-ion transport in the aligned LiNi_0.6Mn_0.2Co_0.2O₂ electrode.

• Steel and Composite Structures
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• v.50 no.6
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• pp.705-720
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• 2024

Analyzing the collapse behavior of thin-walled steel structures holds significant importance in ensuring their safety and longevity. Geometric imperfections present on the surface of metal materials can diminish both the durability and mechanical integrity of steel shells. These imperfections, encompassing local geometric irregularities and deformations such as holes, cavities, notches, and cracks localized in specific regions of the shell surface, play a pivotal role in the assessment. They can induce stress concentration within the structure, thereby influencing its susceptibility to buckling. The intricate relationship between the buckling behavior of these structures and such imperfections is multifaceted, contingent upon a variety of factors. The buckling analysis of thin-walled steel shell structures, similar to other steel structures, commonly involves the determination of crucial material properties, including elastic modulus, shear modulus, tensile strength, and fracture toughness. An established method involves the emulation of distributed geometric imperfections, utilizing real test specimen data as a basis. This approach allows for the accurate representation and assessment of the diversity and distribution of imperfections encountered in real-world scenarios. Utilizing defect data obtained from actual test samples enhances the model's realism and applicability. The sizes and configurations of these defects are employed as inputs in the modeling process, aiding in the prediction of structural behavior. It's worth noting that there is a dearth of experimental studies addressing the influence of geometric defects on the buckling behavior of cylindrical steel shells. In this particular study, samples featuring geometric imperfections were subjected to experimental buckling tests. These same samples were also modeled using Finite Element Analysis (FEM), with results corroborating the experimental findings. Furthermore, the initial geometrical imperfections were measured using digital image correlation (DIC) techniques. In this way, the response of the test specimens can be estimated accurately by applying the initial imperfections to FE models. After validation of the test results with FEA, a numerical parametric study was conducted to develop more generalized design recommendations for the stainless-steel shell structures with the initial geometric imperfection. While the load-carrying capacity of samples with perfect surfaces was up to 140 kN, the load-carrying capacity of samples with 4 mm defects was around 130 kN. Likewise, while the load carrying capacity of samples with 10 mm defects was around 125 kN, the load carrying capacity of samples with 14 mm defects was measured around 120 kN.