• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.295-305
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• 2004

Colloid and surface chemistry have been focused on surface area and surface energy. Local surface properties such as surface density, interaction, molecular orientation and reactivity have been one of interesting subjects. Systems of such surface energy being important would be listed as association colloid, emulsion, particle dispersion, foam, and 2-D surface and film. Such nanoparticle systems would be applied to drug delivery systems and functional cosmetics with biocompatible and degradable materials, while nanoparticles having its size of several nm to micron, and wide surface area, have been accepted as a possible drug carrier because their preparation, characteristics and drug loading have been inves-tigated. The biocompatible carriers were also used for the solubilization of insoluble drugs, the enhancement of skin absorption, the block out of UV radiation, the chemical stabilization and controlled release. Nano/micro emulstion system is classified into nano/microsphere, nano/microcapsule, nano/microemulsion, polymeric micelle, liposome according to its prep-aration method and size. Specially, the preparation method and industrial applications have been introduced for polymeric micelles self-assembled in aqueous solution, nano/microapsules controlling the concentration and activity of high concen-tration and activity materials, and monolayer or multilayer liposomes carrying bioactive ingredients.

• Korean Journal of Social Welfare
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• v.59 no.4
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• pp.191-216
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• 2007

This study focuses on the problem of feminization of poverty that is formed within family relations. In order to approach this question, this study analyses the process of becoming poor through the life stories of ten woman are now heads of a household. There are differences among the study participants in the process of becoming a member of a low-income class. I have classified them into two groups depending on the routes they are led into the low-income class; one is the continuation of poverty group, and the other is the new members of the low-income class group. The continuation of poverty group is the case where they have been poor since their childhood and are still poor in their adulthood. The new members of the low-income class group is the case where you have become a low-income class sometime around divorce. The difference of the groups are related to the differences of the ways the power relationships work within a family. Women head of a household are prone to poverty because of the discrimination in formation, distribution and control of resources in their original family and their family formed by marriage. The norm of male breadwinner worked as a discrimination device. But this kind of discrimination device showed differences in their workings according to class. The continuation of poverty group experienced exclusion in the gendered responsibility of supporting the family and maintaining the family, whereas the other group experienced exclusion through the gendered nature of the distribution and control of resources. By showing that the presupposition of discussions on the poverty of woman head of a household is false, these findings challenge the existing view that as long as 'The Family' is maintained women will not be poor.

• Journal of the Korea Convergence Society
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• v.9 no.3
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• pp.257-263
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• 2018

Hyperthermia supplies RF high-frequency energy above 1MHz to the tumor tissue through the electrodes. And the temperature of the tumor tissue is increased to $42^{\circ}C$ or more to cause thermal necrosis. A mathematical model can be derived a human body model for absorption and transmission of electromagnetic energy in the human model and It is possible to evaluate the distribution of temperature fields in biological tissues. In this paper, we build the human model based on the adult standard model of the geometric shape of the 3D model and use the FVM code. It is assumed that Joule heat is supplied to the anatomical model to simulate the magnetic field induced by the external electrode and the temperature distribution was analyzed for 0-1,200 seconds. As a result of the simulation, it was confirmed that the transferred energy progressively penetrates from the edge of the electrode to the pulmonary tumors and from the skin surface to the subcutaneous layer.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.1 s.49
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• pp.121-125
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• 2005

Most of the cells, specially in the skin, free radicals and reactive oxygen species induced aging, accompanying with diseases. The pinaceae family is very familiar plant with Korean spirit. However, those plants were not estimated for natural products in manufactural process. We employed 4 different plants, Pinus koraienis S et Z. Pinus banksiana LAMBERT. Pinus rigida MILL. Pinus densiflora S. et Z. in pinceae family. The ethanol extracts were prepared for three different parts of plant, wood, bark and leaf, respectively. In this study, we carried out free radical and superoxide radical scavenging assay to investigate the anti-oxidative activity The bark and leaf part of plants showed similar anti-oxidant effect. L-ascorbic acid and $\alpha$-tocopherol at $10{\mu}g/mL$. Also we tried to investigate inhibitory effects of elastase activity in in vitro experiments on pinaceae plant extract as a matters for functional cosmetics. Among those plants, the bark of Pinus rigida MILL. and Pinus densiflora S. et Z. showed inhibitory effect. The cell viability was evaluated with MTT assay. The potential relationship was shown between the cell viability and anti-oxidant effect because the anti-oxidant effects were positively correlated wvith the cell growth in MTT assay. As the results in our experiments, we expect the potential activities of pinaceae as a material of functional cosmetics.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.47 no.1
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• pp.85-92
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• 2021

The stratum corneum is formed from keratinocytes and intercellular lipids, with ceramide as the main component of intercellular lipids. Ceramides are one of the important components of the intercellular lipids to form a lamellar structure, but they are insoluble and therefore are not suitable for direct application to the skin. Thus, it was intended to apply ceramide to the formulation of pluronic lecithin organogel (PLO gel), which received constant attention among drug delivery systems. A suitable oil for formulation was selected and a PLO gel containing ceramide was manufactured. Liquid crystal formation and variation were observed using polarized microscopes, and viscoelastic analysis was performed to find out the viscoelastic behavior of the PLO gel. Small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS) analysis were performed to confirm the structures in the formulation. Results showed that the size and stability of the liquid crystal differed depending on the content ratio of ceramide and lecithin in the PLO gel containing ceramide. Furthermore, viscoelastic analysis showed the stability of the formulation, and SAXS/WAXS analysis confirmed that the PLO gel without ceramide had hexagonal structure of the quadrilateral system array, and the PLO gel with ceramide had the lamellar structure of the quadrilateral system array.

• Journal of Food Hygiene and Safety
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• v.35 no.3
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• pp.225-233
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• 2020

By the standards and specifications for hygiene products, three test methods for formaldehyde are specified for each item type of hygiene product. After derivatization using acetylacetone and 2,4-dinitrophenylhydrazine (2,4-DNPH), formaldehyde is analyzed by spectrophotometer and high-performance liquid chromatography (HPLC). Validation of the three test methods was performed on tissue, diaper lining and waterproof layer, and panty liner products. The results of linearity (R²), limit of detection (LOD), limit of quantification (LOQ), recovery rate (%) and reproducibility (%), showed that all three methods are suitable for analyzing formaldehyde in hygiene products. After derivatization with 2,4-DNPH and cetylacetone, formaldehyde was analyzed at 0, 3, 6, 9, 24 and 48 hours by HPLC. Formaldehyde derivatized with 2,4-DNPH showed no statistically significant change in formaldehyde peak area over time (P>0.05). But, acetylacetone-derivatizated formaldehyde showed a negative correlation coefficient (r) over time (P<0.01). We investigated the residual amounts of formaldehyde in 205 hygiene products distributed in Busan. Among 74 disposable diaper products tested, 73 had low concentrations of formaldehyde (0.13-29.87 mg/kg). Moreover, formaldehyde was not detected in any of 78 tissue, 27 disposable paper towel, 12 disposable dishcloth, 7 paper cup, one brand of paper straw and 6 disposable napkin products.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.9
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• pp.717-722
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• 2001

This paper presents a methodology on the backward path tracking control of a trailer type robot which consists of two parts: a tractor and a trailer. It is difficult to control the motion of a trailer vehicle since its dynamics is non-holonomic. Therefore, in this paper, the modeling and parameter estimation of the system using a real-coded genetic algorithm(RCGA) is proposed and a backward path tracking control algorithm is then obtained based on the linearized model. Experimental results verify the effectiveness of the proposed method.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.1
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• pp.75-85
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• 2016

Pectin, a naturally occurring polysaccharide, has in recent years attracted considerable attention. Its benefits are increasingly appreciated by scientists and consumers due to its safety and usefulness. The chemistry and gel-forming characteristics of pectin have enabled to be used in pharmaceutical industry, health promotion and treatment. Yet, it has been rarely used in cosmetics because of its incompatibility with many cosmetic ingredients, including alcohols, and unstable viscosity of pectin gels under various pH and salt conditions. However, low-molecular-weight pectin oligomers have excellent biological activities, and depolymerization of pectin to produce cosmetic ingredients would be very useful. In this study, we attempted the development of cosmetic ingredients using pectin with an excellent effect on human skin. We developed a bio-conversion process that uses enzymatic hydrolysis to produce pectin hydrolysates containing mainly low-molecular-weight pectin oligomers. Gel permeation chromatography was used to determined the ratio of hydrolysis. The molecular weight of the pectin hydrolysates obtained varied between 200 and 2,700 Da. The two newly developed low-molecular-weight pectin hydrolysates, LMPH A and B, had higher anti-oxidative activities than pectin or D-galacturonic. Exposure to UVB radiation induces apoptotic cell death in epidermal cells. Annexin V binding and propidium iodide uptake were measured by flow cytometry to evaluate UVB-induced cell death in HaCaT cells. Both LMPH A and B reduced UVB-induced cell death and increased cell proliferation by 22% and 30% at 0.5% concentration respectively, while pectin had no significant activity. In conclusion, this study suggests that the newly developed low-molecular-weight pectin hydrolysates can be used as safe and biologically active cosmetic ingredients.

• Journal of Chest Surgery
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• v.42 no.4
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• pp.434-440
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• 2009

Background: Surgical closure of a patent ductus arteriosus (PDA) can be considered when conservative medical treatment is ineffective or contraindicated. Low weight and earlier gestational age neonates who are treated with conservative medical therapy generally showed a higher failure rate. The morbidity of surgical PDA closure in such extremely low birth weight (ELBW) neonates is also high. Here we present the early results of a new technique for approaching the PDA through a dorsal minithoracotomy. Material and Method: From March 2006 to November 2008, 24 premature neonates underwent surgical PDA closure. The procedures were performed in the newborn intensive care unit via a 2 cm long dorsal minithoracotomy with the baby in the prone position with the left hemithorax elevated 30$^{\circ}$. Bimanual cotton swab blunt dissection completed the extrapleural accesstothe PDA and then two clips were applied. Tube thoracostomy was avoided if there was no meaningful pleural laceration. Result: The infants mean gestational age was 26.5$\pm$2.1 weeks (range: 23 to 30 weeks) and the average age at operation was 11$\pm$11 days. The mean body weight at operation was 933$\pm$271 grams (range: 570 to 1,700 grams). Eight patients expired, but there was no procedure-related death. Postoperative echocardiography revealed two cases of residual shunt but none of these shunts were detected on the follow up echocardiogram that was performed on the post operative 5 and 59 days. Conclusion: We concluded that the technique described here is an effective procedure in view of the satisfactory operative exposure and the low rate of complications.

• Tuberculosis and Respiratory Diseases
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• v.49 no.4
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• pp.432-440
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• 2000

Background : The prevalence of pulmonary tuberculosis among the elderly is increasing in Korea and in the developed countries due to the increased elderly population and their predispositions to chronic disease, poverty and decreased immunity. To define the characteristics of pulmonary tuberculosis in the elderly, we evaluated the clinical spectrum of pulmonary tuberculosis. Method : We analyzed 92 patients retrospectively that were diagnosed as active pulmonary tuberculosis over the age of 65. The analysis involved patient's profiles, clinical manifestations, coexisting diseases, diagnostic methods, anti-TB medications and their side effects, and treatment outcomes. Results : The results were as follows : - 1) The ratio of male to female was 2.1:1(62:30 cases) 2) Chief complaints were a cough (47.8%), dyspnea (40.2%), sputum (38.0%), chest pain (12.0%), anorexia (10.9%), and fever (9.8%). 3) 38 (41.3%) of cases had a past history of pulmonary tuberculosis. 4) The coexisting diseases were : -COPD, 25 cases (27.2%); pneumonia, 17 cases (18.5%); DM. 13 cases (14.1%); and malignancy, 10 cases (10.9%). 5) The positivity of Mantoux test (5 TU, PPD-S) was 82.7%. 6) Pulmonary tuberculosis was diagnosed using the following methods : sputum AFB (Acid Fast Bacillus) smear 42.4%, sputum TB (M. Tuberculosis) culture 15.2%, sputum TB PCR (Polymerase Chain Reaction) 10.9%, bronchial washing AFB smear 2.1%, chest radiology only 25.0%. 7) Locations of radiologic lesions were RULF, 50 cases; RLLF, 50 cases, mostly, then LLLF ; 26 cases were leastly involved. 8) The coexisting tuberculosis were endobronchial TB(8.7%), TB pleurisy(7.6%) miliary TB(5.4%), intestinal TB(2.2%), renal TB(1.1%) 9) The proportion of treatment regimen with 1st line drug and 2nd line drug were 92.3% and 7.6%, respectively. 10) The outcome of treatment were as follows : cured 31.5%, expired 13.0%, no return 47.8%, follow-up now 7.6%. Conclusion : The pulmonary tuberculosis in the elderly has atypical patterns with chronic coexisting diseases. Therefore, the possibility of pulmonary tuberculosis should be considered in elderly patients with pulmonary symptoms.