• Archives of Plastic Surgery
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• v.34 no.1
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• pp.111-114
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• 2007

Purpose: Dystrophic calcification occurs in damaged or devitalized tissues in the presence of a normal calcium and phosphorus metabolism. There are many reports on dystrophic calcification caused by injections of various types of drugs. The aim of this report is to highlight the fact that dystrophic calcification can be caused by the injection of a foreign body for aesthetic augmentation. Methods: This case report describes a patient presenting with dystrophic calcification caused by an injection of an unknown foreign body approximately 50 years ago. An 80-year-old man had localized cellulitis with swelling and ulceration on the dorsum of the left hand. The radiographs demonstrated a $5{\times}3.5{\times}1.7cm$ lesion between the first and second metacarpal bones and a $5{\times}2.5{\times}1.5cm$ lesion in the hypothenar region. The laboratory data and physical examinations were generally within the normal limits. The microscopic examination revealed dead bone fragments and dense collagenous tissue with dystrophic calcification. Results: After surgically removing the masses, the resulting defects were treated with an abdominal flap. The result was satisfactory in terms of symptoms and appearance. Conclusion: This case suggests that dystrophic calcification can be caused by an injection of a foreign body for aesthetic augmentation.

• Journal of Preventive Medicine and Public Health
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• v.45 no.1
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• pp.37-46
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• 2012

Objectives: This study was performed to consider the association between Internet using time for non-educational purposes and adolescent health, and to examine how health status differs between Internet users and non-users. Methods: We analyzed 2009 data from the Korea Adolescent Risk Behavior Web-Based Survey, conducted on a nationally representative sample of students in grades 7 to 12. A total of 75 066 adolescents were categorized into four groups according to their Internet using time excluding using for educational purposes: non-Internet users (NIUs), occasional Internet users (OIUs) (<1 h/d), moderate Internet users (MIUs) (${\geq}1$ and <2 h/d), and heavy Internet users (HIUs) (${\geq}2$ h/d). Health factors included eight health risk behavior indices, four mental health indices and six physical health indices. Results: The distribution of Internet use was as follows: NIUs 17.4%, OIUs 68.1%, MIUs 12.7%, and HIUs 1.7%. In multivariate analysis, using OIUs as a reference, U- or J-shaped associations were observed for five health risk behavior indices (current smoking, current drinking, drug abuse, sexual intercourse, sedentary behavior on weekdays) and four mental health indices (stressed, depressed, suicidal ideation, attempted suicide) in both genders. After removing confounding effects, including age, region, school type, subjective school record, subjective economic status, presence of parents, living with family, and sedentary behavior, these associations were still observed. Conclusions: Health professionals should consider both Internet non-users (for non-educational purposes) and heavy users to be high-risk groups in terms of health status. Also, more well-designed studies are needed to clarify what factors are working in these nonlinear associations.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.9
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• pp.3231-3249
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• 2014

Deniable encryption, introduced in 1997 by Canetti, Dwork, Naor, and Ostrovsky, guarantees that the sender or the receiver of a secret message is able to "fake" the message encrypted in a specific ciphertext in the presence of a coercing adversary, without the adversary detecting that he was not given the real message. Sender - side deniable encryption scheme is considered to be one of the classification of deniable encryption technique which defined as resilient against coercing the sender. M. H. Ibrahim presented a sender - side deniable encryption scheme which based on public key and uncertainty of Jacobi Symbol [6]. This scheme has several problems; (1) it can't be able to derive the fake message $M_f$ that belongs to a valid message set, (2) it is not secure against Quadratic Residue Problem (QRP), and (3) the decryption process is very slow because it is based dramatically on square root computation until reach the message as a Quadratic Non Residue (QNR). The first problem is solved by J. Howlader and S. Basu's scheme [7]; they presented a sender side encryption scheme that allows the sender to present a fake message $M_f$ from a valid message set, but it still suffers from the last two mentioned problems. In this paper we present a new sender-side deniable public-key encryption scheme with fast decryption by which the sender is able to lie about the encrypted message to a coercer and hence escape coercion. While the receiver is able to decrypt for the true message, the sender has the ability to open a fake message of his choice to the coercer which, when verified, gives the same ciphertext as the true message. Compared with both Ibrahim's scheme and J. Howlader and S. Basu's scheme, our scheme enjoys nice two features which solved the mentioned problems: (1) It is semantically secure against Quadratic Residue Problem; (2) It is as fast, in the decryption process, as other schemes. Finally, applying the proposed deniable encryption, we originally give a coercion resistant internet voting model without physical assumptions.

• Journal of the Korean institute of surface engineering
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• v.51 no.4
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• pp.191-196
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• 2018

The self-annealing which leads evolution of microstructure in copper electroplating layers at room temperature occurs after forming deposition layer. During the process, crystal orientation, size and sheet resistance of plating layer change. Lastly, it causes the change of physical and mechanical characteristics such as a tensile strength of plating layer. In this study, the variation of incorporated impurities, microstructure and sheet resistance of copper plating layer formed by electroplating are measured with and without inorganic additives during the self-annealing. In case of absence of inorganic additives, the copper layer presents strong total intensity of incorporated impurities. During the self-annealing, such width of reduction was significant. Moreover, microstructure and crystal size are increased while the tensile strength is decreased noticeably. On the other hand, in the presence of inorganic additives, there is no observable distinction in the copper plating layer. According to the observation on movements of the incorporated impurities in electrodeposition copper layer, within 12 hours the impurities are continuously shifted from inside of the plating layer to its surface after as-deposited electroplating. Within 24 hours, except for the small portion of surface layer, it is considered that most of the microstructure is transformed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.6
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• pp.516-521
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• 2019

The top seeded solution growth (TSSG) method is an alternative technique to grow high-quality SiC crystals that has been actively studied for the last two decades. However, the TSSG method has different issues that need to be resolved when compared to the commercial SiC crystal growing method, i.e., physical vapor transport (PVT). A particular issue of the TSSG method of results from the presence of liquid droplets on the grown crystal that can remain even after crystal growth; this induces residual stress on the crystal surface. Hence, the residual droplet causes several unwanted effects on the crystal such as the initiation of micro-cracks, micro-pipes, and polytype inclusions. Therefore, this study investigated the formation of the residual droplet through multiphysics simulations and lead to the development of a liquid droplet removal method. As a result, we found that although residual liquid droplets significantly apply residual stress on the grown crystal, these could be vaporized by adopting thermal annealing processes after the relevant crystal growing steps.

• Structural Engineering and Mechanics
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• v.57 no.5
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• pp.837-859
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• 2016

An efficient shear deformation theory is developed for wave propagation analysis of an infinite functionally graded plate in the presence of thermal environments. By dividing the transverse displacement into bending and shear parts, the number of unknowns and governing equations of the present theory is reduced, and hence, makes it simple to use. The thermal effects and temperature-dependent material properties are both taken into account. The temperature field is assumed to be a uniform distribution over the plate surface and varied in the thickness direction only. Material properties are assumed to be temperature-dependent, and graded in the thickness direction according to a simple power law distribution in terms of the volume fractions of the constituents. The governing equations of the wave propagation in the functionally graded plate are derived by employing the Hamilton's principle and the physical neutral surface concept. There is no stretching.bending coupling effect in the neutral surface-based formulation, and consequently, the governing equations and boundary conditions of functionally graded plates based on neutral surface have the simple forms as those of isotropic plates. The analytic dispersion relation of the functionally graded plate is obtained by solving an eigenvalue problem. The effects of the volume fraction distributions and temperature on wave propagation of functionally graded plate are discussed in detail. It can be concluded that the present theory is not only accurate but also simple in predicting the wave propagation characteristics in the functionally graded plate. The results carried out can be used in the ultrasonic inspection techniques and structural health monitoring.

• Journal of Sasang Constitutional Medicine
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• v.25 no.3
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• pp.195-207
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• 2013

Objectives This study aimed to examine differences in the hepatic function disorders and prevalence rates of liver diseases in accordance with the Sasang constitutional type, and to analyze whether Sasang constitution is a significant risk factor for fatty liver. Methods A total of 1211 patients who underwent health check-up at the Ilsan Hospital of Dongguk University and had their physical constitutions diagnosed by a specialist in Sasang constitutional medicine from October 31, 2011 to September 28, 2012 were used as the subjects of this study. Presence of hepatobiliary diseases was analyzed from the results of the hepatic function test, lipid test and viral hepatitis infection marker test in the biochemistry tests, and abdominal ultrasonography. Results & Conclusion Subjects of the study were composed of 691 males and 520 females and, in terms of Sasang constitution distribution, 550 Taeeumin, 343 Soeumin and 318 Soyangin. As the results of analysis of prevalence rates in accordance with Sasang constitutions, significant differences were observed in the prevalence rates of abnormal groups in the cases of AST, ALT, GGT, Triglyceride, HDL-cholesterol and LDL-cholesterol, and all of their prevalence rates were in the descending order of Taeeumin, Soyangin and Soeumin. Soeumin displayed significantly higher positive rate for HBs Ab in comparison to Taeeumin and Soyangin. In the results of abdominal ultrasonography, the prevalence rates of fatty liver displayed significant differences and were in the descending order of Taeeumin, Soyangin and Soeumin. And as the result of logistic regression analysis in order to find the risk factors of fatty liver, the Sasang constitution was found to be a significant risk factor for fatty liver. The odds ratio of Taeeumin in fatty liver was found to be 1.634 higher than Soeumin and 1.773 higher than Soyangin

• Nuclear Engineering and Technology
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• v.16 no.3
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• pp.169-179
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• 1984

An efficient procedure of evaluating the fuel cladding failures occurring in the normal operations of typical PWR's has been investigated through the analysis of fission product(FP) activities in the reactor coolant using an analytical model, FIPREL code. Performed by this code is an extensive study on the sensivities of FP activities to such physical parameters as enrichment, turnup, and operation temperature of failed fuel rod as well as the effective failure size quantified in terms of the magnitude of gap release coefficient. The results of study are generally in agreement with those by PROFIP method. In the presence of tramp uranium the portion of activities released from failed rod is separated by an iterative calculation based on the activity ratios of fission nuclides chemically more stable than iodines. Obtained are the linear power density and the number of failed rods, the effective failure size, and the mass of tramp uranium. The operation experiences of 4 cycles of Kori Unit 1 are analyzed and the results show that the model is highly reliable for the survey and evaluation of fuel rod conditions during reactor operations.

• YAKHAK HOEJI
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• v.42 no.1
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• pp.59-69
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• 1998

To increase the solubility of quercetin, which is a practically insoluble flavonoid of Ginkgo biloba leaf, the effects of nonaqueous vehicles. Their cosolvents, water-sol uble polymers and modified cyclodextrins (CDs) were observed. Polyethylene glycols, diethyleneglycol monoethyl ether, and their cosolvents with water showed a good solvency toward quercetin. Also the aqueous solutions of povidone, copolyvidone and Cremophor RH 40 was effective in solubilizing quercetin. Complex formation of quercetin with ${\beta}$-cyclodextrin (${\beta}$-CD), dimethyl-${\beta}$-cyclodextiin (DMCD), 2-hydroxypropyl-${\beta}$-cyclodextrin (HPCD) and ${\beta}$-cyclodextrin sulfobutyl ether (SBCD) in water was investigated by solubility method at $37^{\circ}C$. The addition of CDs in water markedly increased the solubility of quercetin with increasing the concentration. AL type phase solubility diagrams were obtained with CDs studied. Solubilizaton efficiency by CDs was in the order of SBCD >> DMCD > HPCD > ${\beta}$-CD. The dissolution rates of quercetin from solid dispersions with copolyvidone, povidone and HPCD were much faster than those of drug alone and corresponding physical mixtures, and exceeded the equilibrium solubility (3.03${\pm}1.72{\mu}$g/ml). The permeation of quercetin through duodenal mucosa did not occur even in the presence of enhancers such as bile salts, but the permeation was observed when the mucus layer was scraped off. This was due to the fact that quercetin had a strong binding to mucin ($58.5{\mu}$g/mg mucin). However rutin was permeable to the duodenal mucosa. The addition of enhancer significantly increased the permeation of rutin in the order of sodium glycocholate.

• Journal of Soil and Groundwater Environment
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• v.25 no.2_spc
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• pp.86-100
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• 2020

Analyzing and monitoring environmental contaminants based on geophysical exploration techniques have become important and it is now widely applied to delineate spatial distribution geophysical characteristics in wide area. Among the techniques, induced polarization (IP) method, which measures polarization effects on electrical potential distribution, has drawn much attention as an effective tool for environmental monitoring since IP is sensitive to changes in biochemical reactions. However, various reactions stemming from the presence of multiple contaminants have greatly enhanced heterogeneity of polluted sites to result in highly variable electrical characteristics of the site. Those contaminants influence chemical and physical state of soil and groundwater to alter electrical double layer, which in turn influences polarization of the media. Since biochemical reactions between microbes and contaminants result in various IP effects, IP laboratory experiments were conducted to investigate IP responses of the contaminated soil samples under various conditions. Field IP surveys can delineate the spatial distribution of contamination, while providing additional information about electrical properties of a target medium, together with DC resistivity. Reviewing IP effects of contaminants as well as IP surveys can serve as a good starting point for the application of IP survey in site assessment for environmental remediation.