• Economic and Environmental Geology
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• v.47 no.6
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• pp.563-569
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• 2014

Ruby is one of the most favor colored gem, for beautiful red tone, be high in scarcity value. However, rubies with high quality are produced in restricted regions, such as in Thailand, Sri Lanka, Myanmar, and Tanzania etc., and they have been gradually exhausted by mining for a long period. Therefore, improving qualities of low level rubies with various treatments is arising an alternative way to obtain better rubies. Gemological and mineralogical properties of the natural ruby from Tanzanian were studied with heat treatments. Those characteristics were compared between only heat and adding flux materials under heating. Tanzanian raw rubies were applied a heat treatment ($1,600^{\circ}C$ for 6 hours). However, chromameter and UV-Vis analyses found that a simple heat treatment is inappropriated for the Tanzanian ruby. Although $Cr^{3+}$ containing for red color in the ruby increased with heat treatment, the ruby displays dark medium red because of Fe in the ruby as a form of $Fe_2O_3$. The low transparency after heat treatment is attributed to the recrystallization of $SiO_2$ which has a low melting point. Chromameter confirmed adding Pb-containing flux under heating greatly improves the clarity and color of Tanzanian rubies with micro-fractures and cavities on the surface. EMPA results show that Pb as an additive fills the cavities and cracks on raw Tanzanian rubies during the heat treatment. As a rewult of it, the quality of the Tanzanian ruby raw dramatically improved. These results indicate that the heat treatment with an additive (Pb in this study) is an effective way to obtain better quality of the Tanzanian ruby. Consequently, this study suggests a suitable method to improve the properties of the Tanzanina ruby. The result of this study would provide useful information to upgrade the qualities of similar gem stones such as corundum and sapphire.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.1-8
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• 2017

As the IT environment becomes more sophisticated, various threats and their associated serious risks are increasing. Threats such as DDoS attacks, malware, worms, and APT attacks can be a very serious risk to enterprises and must be efficiently managed in a timely manner. Therefore, the government has designated the important system as the main information communication infrastructure in consideration of the impact on the national security and the economic society according to the 'Information and Communication Infrastructure Protection Act', which, in particular, protects the main information communication infrastructure from cyber infringement. In addition, it conducts management supervision such as analysis and evaluation of vulnerability, establishment of protection measures, implementation of protection measures, and distribution of technology guides. Even now, security consulting is proceeding on the basis of 'Guidance for Evaluation of Technical Vulnerability Analysis of Major IT Infrastructure Facilities'. There are neglected inspection items in the applied items, and the vulnerability of APT attack, malicious code, and risk are present issues that are neglected. In order to eliminate the actual security risk, the security manager has arranged the inspection and ordered the special company. In other words, it is difficult to check against current hacking or vulnerability through current system vulnerability checking method. In this paper, we propose an efficient method for extracting diagnostic data regarding the necessity of upgrading system vulnerability check, a check item that does not reflect recent trends, a technical check case for latest intrusion technique, a related study on security threats and requirements. Based on this, we investigate the security vulnerability management system and vulnerability list of domestic and foreign countries, propose effective security vulnerability management system, and propose further study to improve overseas vulnerability diagnosis items so that they can be related to domestic vulnerability items.

• Journal of Nutrition and Health
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• v.49 no.5
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• pp.323-334
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• 2016

Purpose: The purpose of this study was to estimate intakes of macronutrients and antioxidant vitamins according to the Hansik consumption rate among Korean adults. Methods: Using data from the 2007~2012 Korea National Health and Nutrition Examination Survey, a total of 33,069 subjects aged over 19 years old were included in this study. We estimated individual daily Hansik consumption rates and intakes of macronutrients and antioxidant vitamins, including vitamin A and its subgroup such as retinol, ${\alpha}$-carotene, ${\beta}$-carotene, and ${\beta}$-cryptoxanthin, vitamin C, and vitamin E, by linking food consumption data with the nutrient and antioxidant vitamin database of commonly consumed foods. Results: Around 75% of subjects consumed Hansik in over 75% of their daily total consumed food. The most frequently consumed Hansik was cabbage kimchi (1.57 times/day), followed by multigrain rice (0.86 times/day) and white rice (0.80 times/day). The household income level and education level was inversely associated with the Hansik consumption rate. There was a positive relationship between Hansik consumption rate and vitamin A, ${\beta}$-carotene, ${\beta}$-cryptoxanthin, and vitamin C intakes. On the other hand, Hansik consumption rate was inversely associated with energy and fat intake. Conclusion: The results of this study suggest that Hansik consumption could provide more antioxidant vitamins and less energy and fat. Thus, further research will be needed to analyze the association between Hansik and health effects.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.3
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• pp.498-503
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• 2006

This in vitro study compared the remineralization of incipient interproximal caries in the presence of three glass ionomer cements (highly-filled glass ionomer cement, compomer, resin-modified glass ionomer cement) and a resin composite(control). The long-term changes in remineralization caused by each material were evaluated by microtomography. Proximal restoration was simulated by placing tooth specimens and the various glass ionomer cements in closed containers with artificial saliva at $37^{\circ}C$ and pH 7.0 for 30 days with constant circulation Tomographic images were obtained with a micro CT scanner at 90, 180, and 270 days, and density-measuring software was used to calculate the micro-density of artificial caries lesions in the specimens. The mean density changes were compared between groups in order to evaluate the effects of remineralization. All data were analyzed using one-way ANOVA and the post-HOC Tukey multiple comparison test at p<0.05. While the density of artificial caries lesions increased for all treatments, the increases for the three glass ionomer groups were significantly higher than that for the resin group in each three month period. As time went on, the amount of density increase of the glass ionomer groups decreased, and significant differences were found between the remineralization effects of the glass ionomer groups.

• Economic and Environmental Geology
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• v.51 no.4
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• pp.345-358
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• 2018

In this study, we have performed electron probe micro analyzer (EPMA), X-ray differaction (XRD), inductively coupled plasma spectroscopy (ICP), Fourier transform Raman spectroscopy (FT-Raman), far-infrared (FIR), nuclear magnetic resonance (NMR), and pH-DO Analyses for characterizing medicinal mineralogy aspect of the black tourmaline (Shantung, china), black and pink tourmaline (Minas Geraris, Brazil), black touemaline (Daeyu mine, Korea). In addition, heating effects of the tourmaline sauna as well as the effects of tourmaline powder-added soap on skin troubles have been investigated. It has been revealed that chemical composition of the tourmaline is either high in Fe-, Al-, B-rich types. Ratio of the K-Ca, Na-K, and Fe-B reflects the component change property of solid solution. $CaO/CaO+Na_2O$ and MgO/FeO+MgO ratio show high positive correlation. When tourmaline reacts with distilled water, extended reaction time DO values approximately decrease and it stabilizes at DO = 10. Otherwise, pH values increase until 6 hours and it stabilizes at pH = 8 after 24 hours. Distilled water changes to alkaline when it reacts with tourmaline powder and particles. Tourmaline showed lower absorption spectrum strength and transmittance at short wave, where absorption spectrum wavelength and strength were determined by the content of the composition elements and characteristics of crystallography. Increase of the Fe content has been confirmed to be the cause for the reduction of irradiation. For the chemical composition and spectral property of the tourmaline particle samples, it has been found that Si and Fe contents show positive correlation with Far-Infrared irradiation, while Al and Mg contents show negative correlation. For tourmaline powder, it has been confirmed that $^{17}O-NMR$ FWHM (full width at half maximum) decreases when reacts with distilled water. Tourmaline sauna (approximately $100^{\circ}C$) was found to increase $0.5-1.5^{\circ}C$ of body temperature, average of 12 heartbeat, and 10mg Hg of blood pressure. Tourmaline soap had very good aesthetic effect to skin and was confirmed to have above the average improvements to skin troubles (e.g., allergy or atopy).

• Journal of the Korean GEO-environmental Society
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• v.16 no.12
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• pp.45-52
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• 2015

With the rising interest in the environment, more attention on ecological restoration for damaged slope surface to restore its original state has been drawn. Generally, the most useful method is vegetation based spray work. This method uses green soil including sewage sludge, sawdust, paper sludge, and weathered granite soil. However, because there are neither accurate information nor test values about green soil, green soil is often lost by environmental factors such as rainfalls and strong winds. To solve the problem of green soil, it is necessary to prepare design standards about green soil, and conduct studies to deal with green soil loss in consideration of various variables including basic material property, soil quality of slope surface, and weather. This study was conducted in the mixture of green soil and eco-friendly soil stabilizer. With green soil, basic material property test and compaction test were conducted for the analysis on the basic characteristics of green soil. In the mixture with soil stabilizer at a certain ratio, we conducted shear strength test depending on the ratio in order to analyze the maximum shear strength, cohesion and the change in internal friction angles. Furthermore, in the mixture ratio of green soil and soil stabilizer, which is the same as the ratio in the shear strength test, an inclination of slope surface was made in laboratory for the analysis on erosion and germination rate. Finally, this study evaluated the most effective and economic mixing ratio of soil stabilizer to cope with neighboring environmental factors. According to the test, the shear strength of green soil increased up to 51% rely onto the mixing ratio of and a curing period, and its cohesion and internal friction angle also gradually increases. It is judged that the mixture of soil stabilizer was effective in improving shear strength and thereby increased the stability of green soil.

• Journal of the Korean Society of Radiology
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• v.15 no.2
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• pp.265-271
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• 2021

The pattern of the tree's internal swelling depends on many causes. Since it is difficult to detect these various causes of swelling with a general method, if the state of swelling for a long time cannot be confirmed, serious damage to the trees may occur due to enlargement of the swelling area. In the method of acquiring a tree tomography image, an impulse passing through the tree is generated by tapping the sensor with a rubber mallet, and the moving speed is recorded. In this paper, to measure cracks, cavities, and swelling due to physical damage, we developed a 3D viewer that can know the internal state of a tree using a tree cross-section image acquired from Arbotom to determine the degree of swelling inside the tree. Based on this, we tried to present data that can be referred to when surgical operation of trees is required. In order to acquire a tomographic image of a tree, 6 sensors were attached to the three Yangpala and Maple trees, and a 1 m-long tree was measured using the Arbotom program, and a 3D image was implemented through the 3D Viewer created using MATLAB. In addition to simply acquiring images, the cross-sectional length and volume of the tree were measured. In the actually produced 3D Viewer, the length of the part where the swelling of the maple tree occurred was 33.12 cm, and the swelling of the yangpala tree was measured as 21.41 cm. The volume of the maple tree was measured to be 78.832 ㎤. As a result of comparing the cross-sectional image of the Arbotom and the 3D image, the same result as the real aspect of the tree was obtained, so it can be judged that the reliability of the manufactured software is also secured, and data to be applied to the surgical tree operation through the created Viewer is provided. It is believed that the damage will be minimized.

• Korean Journal of Culture and Social Issue
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• v.10 no.1
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• pp.1-30
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• 2004

Study 1 composed of three experiments examined differences in person perception between computer-mediated (or CMC) and face-to-face (or FTF) communications. In Experiment 1, each of 17 groups of 4-5 discussed a donation entrance system through CMC and a week later a college-based university system through FTF communication mode for half an hour. Then members of a given group rated each other along with self-ratings on five personality traits. Results indicated that in FTF than CMC condition, ratings of others were more positive and also self-peer agreement and meta-accuracy were larger in spite of no large difference in inter-judge agreement between two communication modes. In Experiment 2, 17 groups of 4 in each of the CMC and FTF condition discussed a college-based university system for an hour. Then group members rated each other on another five trait dimensions. Although ratings of others were more positive in FTF than CMC condition, there no systematic differences in two types of agreement and meta-accuracy between the two communication modes. In Experiment 3, 17 groups of 4 in each of the CMC and FTF condition discussed a donation entrance system for an hour and then group members rated each other on five trait dimensions different from those used in Experiment 1 and 2. The findings replicated Experiment 1. Study 2 examined gender differences in person perception in CMC. Fifteen dyads for each of the man-man, man-woman, and man-woman conditions communicated for an half hour in CMC and then rated each other along with self ratings on 25 personality trait dimensions. Results indicated that participants rated their partners more negatively for extorversion, agreeableness and culture factors, which was due mainly to woman's negative evaluations for their male partners. Also, self-peer agreement was the largest in the man-man communication condition. These findings were discussed in relation to differences between CMC and FTF communication modes.

• The korean journal of orthodontics
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• v.37 no.6
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• pp.391-399
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• 2007

Three-dimensional approaches for the diagnosis and analysis of the dentofacial area are becoming more popular in accordance with the development of cone-beam CT (CBCT). The purposes of this study were to evaluate the reliability of cephalometric measurements of lateral cephalograms generated from a CBCT image by making comparisons with the traditional digital lateral cephalogram, and to evaluate the possibility of the clinical application of CBCT generated cephalogram images. Methods: Twenty patients whose external auditory meatus could be identified in the CBCT image were selected, and both CBCT and digital cephalograms were taken. Differences between the measurements of both cephalograms were tested by paired t-test. Results: Among the 22 measurements used, only U1-FH, Mx6 to PTV, and maxillomandibular difference showed statistically significant differences between the CBCT generated cephalogram and the digital cephalogram. Conclusions: The results suggest that the CBCT generated cephalogram can be used for some cephalometric measurements not requiring porion, PTV, condylion as a landmark (SNA, SNB, U1 to SN, IMPA, interincisal angle, etc.).

• Journal of Nutrition and Health
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• v.48 no.6
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• pp.507-518
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• 2015

Purpose: The aim of this study was to examine the association of food security with the total and individual flavonoid intakes among Korean adults. Methods: Study subjects were 13,454 men and 19,563 women aged 19 years and older who participated in the 2007~2012 Korea National Health and Nutrition Examination Survey. Subjects were classified into food-secure and food-insecure groups using the answers to a self-reported question on food sufficiency of subjects' household. The total and individual flavonoid intakes were calculated by linking 24-h dietary recall data of subjects with a flavonoid database. Mean differences in dietary outcomes by food security status, and major food sources of total flavonoids were examined. Results: In this cross-sectional study, 5.8% of male adults and 6.6% of female adults were in food insecure households. Mean daily intakes of total flavonoids, flavonols, flavones, flavanones, flavan-3-ols, isoflavones, and proanthocyanidins were significantly lower in food-insecure groups than food-secure groups among both male and female adults. The differences were maintained in total flavonoids, flavones, flavanones, and flavan-3-ols after adjusting for total energy intake. Mean intakes of fruits and vegetables were significantly lower in food-insecure groups and the total flavonoid intake from fruits and vegetables was also significantly lower in food-insecure groups. The major food sources of total flavonoids were apples (20.7%), mandarines (12.0%), and tofu (11.5%) in the food-secure group, and apples (14.9%), tofu (13.3%), and mandarines (12.6%) in the food-insecure group. Conclusion: This study showed that food insecurity was associated with lower intakes of flavonoids and reduced intakes of fruits and vegetables in a representative Korean population.