• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.5
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• pp.95-101
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• 2008

Modeling of stock prices forecast has been considered as one of the most difficult problem to develop accurately since stock prices are highly correlated with various environmental conditions including economics and political situation. In this paper, we propose a agent system approach to predict Korea Composite Stock Price Index (KOSPI) using neural network and statistical methods. To minimize mean of prediction error and variation of prediction error, agent system includes sub-agent modules for feature extraction, variables selection, forecast engine selection, and forecasting results analysis. As a first step to develop agent system for KOSPI forecasting, twelve economic indices are selected from twenty two basic standard economic indices using principal component analysis. From selected twelve economic indices, prediction model input variables are chosen again using best-subsets regression method. Two different types data are tested for KOSPI forecasting and the Prediction results showed 11.92 points of root mean squared error for consecutive thirty days of prediction. Also, it is shown that proposed agent system approach for KOSPI forecast is effective since required types and numbers of prediction variables are time-varying, so adaptable selection of modeling inputs and prediction engine are essential for reliable and accurate forecast model.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.13 no.3
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• pp.47-65
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• 2014

VMS(Variable Message Sign) helps drivers to choose their path to destinations on roadways. Some types of VMS often provide traffic information with clearly visible and comprehensible graphical route diagrams. Currently many diagramed types of VMS are installed on urban arterial and highways. This type of VMS surely enhances drivers' ability to comprehend traffic route information while they are driving on the roadway. Nevertheless, some of them are presented with so much information and design elements and they sometimes lead to decline of drivers' comprehensible level for traffic information. Drivers would fail to decide their preferable route in this state of information overflow. The purpose of this paper is to develop a drivers preference model for effective design principle including size and height of displaying font, and the amount of information in the route diagram considering driving speed, sex and age of the driver. This model is developed using structural equation modeling techniques. This model considers driver's emotional factor and, human factor and design component of route diagram. To collect data, we built driving simulator which is able to replicate real driving condition. 72 people who participated in the simulation were selected considering gender and age. The developed model showed that the amount of information, and visibility are more influential factors to the drivers' preference of the route diagram on VMS than design elements such as the shape and the font of the diagram.

• Tuberculosis and Respiratory Diseases
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• v.42 no.5
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• pp.677-684
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• 1995

Background: Broncholithiasis is uncommon but clinically important because it may cause a variety of nonspecific symptoms and signs prior to the onset of lithoptysis, and rarely massive hemoptysis. Method: A retrospective clinical study was done on 11 case of broncholithiasis diagnosed at Kyungpook National University Hospital from Jan. 1985 to Dec. 1993. The study investigated the clinical features, radiologic findings, bronchoscopic findings and management. Results: 1) The common symptoms included cough, dyspnea, hemoptysis, fever and purulent sputum. Lithoptysis occurred in 3 patients. 2) The radiologic findings were variable and nonspecific. Hilar calcification and parenchymal calcification were the most common findings. 3) The bronchoscopy was performed in 10 patients and revealed broncholiths in 9 patients. 4) Chemical composition of broncholiths was analyzed in 2 patients. Calcium carbonate was main component. 5) In 6 out of 9 patients in whom broncholiths was revealed by bronchoscopy, broncholiths were successfully extracted through the flexible bronchoscope. 6) In 9 patients, broncholithiasis was related to tuberculosis and in 1 case, related to silicosis. Conclusion: Broncholithiasis shows a variable clinical spectrum. Tuberculosis is the most common cause of broncholithiasis. In the case of no accompanied complication, nonsurgical management such as bronchoscopic removal and conservative therapy is an effective measure.

• Culinary science and hospitality research
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• v.21 no.5
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• pp.160-170
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• 2015

In accordance to the increasing number of death due to cancer and side effects of chemotherapy, attention has recently focused on combined treatment of natural component and anti-tumor agent. Therefore development of safe and effective functional substances derived from natural materials is required. The emergence of various functional activities of Rubus coreanus Miquel, such as antioxidant, anticancer, anti-inflammatory, etc. is continuously increasing its consumption. To utilize the above activities, many products developed by using Rubus coreanus Miquel extracts in the areas of foods, liquors, and cosmetics and medicines. In this review, anti-cancer, anti-inflammatory activity and patents of Rubus coreanus Miquel are summarized. Further studies are needed to search for development of functional material from natural origin and various application possibility using stem, leaf and fruit of Rubus coreanus Miquel.

• The Research Journal of the Costume Culture
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• v.18 no.4
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• pp.670-686
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• 2010

This study aims at clarifying the action types of skin management which is base on age, marriage or not, family composition, school career, and income which are demographic variables centering around the lifestyle of middleaged and old age women. As for study method, this researcher executed literature study and questionnaire on adult women over 45 years old who dwell in Seoul and Kyounggi area. Survey period was Mar. 1, 2009 to Jun. 30. And, after distributing 1,000 copies of questionnaire, this researcher used effective 869 copies of questionnaire for analysis out of collected questionnaire, 895 copies. As for analysis method, this researcher executed DUNCAN test with factor analysis, reliability analysis, manin component analysis, K-average, multitude analysis, dispersion analysis and post verification by using SPSS 12.0 program. As for demographic feature for middle aged and old age women, 50~59 years old women were most by age as 302 persons(33.7%). It is emerging that spouse existence is very high as 674 persons(75.3%) in the answer for marriage or not, couple family to live with unmarried children is very high as 483 persons(54.0%) in the answer for family composition, leaving high school in mid-course or gradation of high school are very high as 356 persons(39.8%) in the answer for school career, income from 3 million Won under 4 million won is very high as 260 persons(29.1%) in the answer for monthly income of family members, and women to use under 50 thousand won is very high as 510 persons(57.0%) in the monthly average expense to be used for skin management. In this study, this researcher extracted total 5 factors (economic saving, displaying consumption, confidence inclination, centering around family, and leisure application) by executing factor analysis with 12 question items of lifestyle so as to grasp factor structure of lifestyle of middleaged and old age people, and whole explanatory variable quantity was 70.9%. This researcher named as economic saving type, diplaying consumption style, and type centering around leisure and family, after making multitude analysis about 5 factors analyzed by measuring lifestyle feature. As the result of structure analysis of question items of skin management(pursuit of skin management, life of skin management, and inclination of skin management), this researcher extracted total 3 factors, and whole explanatory variable quantity was 71.30%. Thus, it emerged that there is significant difference among groups.

• Korean Journal of Food Science and Technology
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• v.24 no.2
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• pp.171-176
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• 1992

Volatile flavor components of Codonopsis lanceolata were extracted by gas co-distillation (GCD), solvent extraction/fractionation (SEF), and headspace sampling (HSS) methods. The extracts were analyzed by dual-capillary gas chromatography-retention index (GC-RI) and gas chromatography-mass spectrometry(GC-MS). The two extracts prepared by SEF and HSS gave more similar fragrance to the Codonopsis lanceolata than the GCD extract. The GC profiles of the SEF and HSS extracts were similar to each other except for differences in peak areas. The extract prepared by SEF gave a sweet note while the extract prepared by HSS gave a green note. The GCD extract began to give a burnt note of herb medicine with prolonged distillation. Rapid extraction of flavor components from Codonopsis lanceolata was possible in several short steps by SEF and HSS methods compared to GCD. GC-MS and GC-RI were used for peak identification. GC-RI was more effective for identification of isomers, and polar FFAP column was more suitable for identification of polar compounds. From Codonopsis lanceolata we identified 35 volatile flavor constituents, 24 of which have not been previously reported by simultaneous distillation extraction method $^{(5)}$. trans-2-Hexanal, cis-3-hexen-1-ol, trans-2-hexen-1-ol, and hexanol were considered key components of the green note and 1-octen-3-ol, the component of the fresh note. Esters, including amyl propionate, seem to be responsible for the sweet note particular to Codonopsis lanceolata.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.218-224
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• 2000

The antimicrobial activities of chitosan oligosaccharide(chitohexaose) and two types of chitosans M.W.(10,000 and M.W. 100,000) were examined against Escherichia coli O157 : H7(ATCC 43894), Staphylococcus aureus(ATCC 144458) and Candida albicans(KFRI 432). Chitosan with molecular weight of 10,000 showed the strongest antimicrobial activities to E. coil O157 : H7 and S. aureus, whereas chitohexaose acted most strongly against C. albicans. The most effective concentration of chitosan was measured to be 0.1 mg/mL for E. coil O157 : H7 and S. aureus, and that of chitohexaose to be 1 mg/mL for C. albicans. Antimicrobial activities of chitosans and chitohexaose were maintained for 60 min after their treatment. They were found to induce leakage of intracellular proteins and nucleic acids from treated microorganisms. The efflux determined by assaying the ${\beta}-galactosidase$ leaked from the lactose-induced E. coli O157 : H7 cells was observed to reach the highest level within 60 min after treatment with the antimicrobial agents and chitosan with 10,000 molecular weight gave the highest ${\beta}-galactosidase$ activity. Therefore, it is supposed that the antimicrobial activity of chitosan with its unique polycationic nature might be caused by its binding to anionic component(s) of the cell envelope and thereby inhibiting the membrane metabolism and/or leaking intracellular materials.

• Journal of Life Science
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• v.26 no.6
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• pp.673-679
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• 2016

The development of safe and effective anti-cancer compounds has been seriously required to prevent and treat development of tumor in recent years. Among them, natural compounds derived traditional medicinal stuffs have been paid to attention as an anti-cancer candidate. In this study, aesculetin is a main component of a widely known as a medicinal stuff. It was reported that aesculetin has various biological effects such as anti-inflammatory and anti-bacterial, but its effect related to cell invasion was not discovered. Therefore, in this study, the effect of aesculetin on antioxidant and matrix metalloproteases (MMPs) was investigated in human fibrosarcoma cells, HT1080. First of all, aesculetin showed the scavenging activity of DPPH radical and reducing power in a dose dependent manner. As a result of cytotoxicity, the nontoxic concentration of aesculetin was below 2 μM in HT1080 cells performed by MTT assay. In addition, aesculetin displayed the inhibitory effect on MMP-9 activity related to cell invasion in experiment carried out by gelatin zymography assay. Furthermore, aesculetin increased the expression level of TIMP-1 but decreased the expression level of MMP-9 stimulated with PMA in western blot assay. Furthermore, aesculetin remarkably inhibited cell invasion related to metastasis a dose dependent manner. Above results suggest that aesculetin could exert chemopreventive effect through inhibition of activity and expression of MMP-9 related to cell invasion.

• Journal of Life Science
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• v.24 no.9
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• pp.1001-1005
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• 2014

Ginsenoside Rg3 is one of the active ingredients extracted from red ginseng, and it is an effective chemical component of the human body and well known in herbal medicine as a restorative agent. Several studies have shown that Rg3 has a potent anti-tumor effect on various cancer cell lines. However, Rg3-induced apoptosis in B16F10 melanoma cancer cells is not well understood. In the present study, we tested whether ginsenoside Rg3 could induce apoptosis in B16F10 melanoma cells. We found that Rg3 could inhibit B16F10 melanoma cell viability in a dose-dependent manner, but not normal cells, such as EA.hy.926 and NIH3T3 cells. We also found that Rg3 could induce apoptosis in B16F10 melanoma cells using tunnel-staining assay in a dose-dependent manner. Rg3 treatment induces the phosphorylation of p38 and the expression of Bax, but it inhibits the expressions of the phosphorylation of focal adhesion kinase Bcl2 and pro-caspase3. Taken together, our data suggest that Rg3 could be useful as an anti-cancer agent in B16F10 melanoma cells.

• Korea Journal of Hospital Management
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• v.17 no.1
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• pp.1-22
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• 2012

This study tires to examine affects that job and socio-psychological stresses of female office workers influence job satisfaction, organization commitment, and leaving intentions. A complete data are collected by conducting a survey with 240 female office workers from 9 medical institutions regarded as almost general hospital in Seoul. It is analyzed that the relation between socio-psychological stress and job satisfaction, organization commitment, and leaving intentions by using t-test; analysis of variance; correlation analysis; principal component analysis; linear structural equation modeling; etc. The results of this study are summarized as following. First, as it was comprehended by specific characteristics of subjects that the female office workers' level of job and socio-psychological stress, job satisfaction, organizational commitment, and leaving intention, there were statistically significant distinctions from their age, marital status, presence of children, position in the organization, type of employment, and monthly average income. Second, this study regarded relationship between the female office workers' level of job and socio-psychological stresses, job satisfaction, organizational commitment, and leaving intention. Job and socio-psychological stresses were negatively correlated with job satisfaction and organizational commitment, but the stresses were positive with leaving intention. Third, after evaluating effect that 8 features related to the job stress could influence job stress, the most effective valuables were in order to unfairness in organizational structure, workplace culture, inadequate compensation, and relationship conflict. Fourth, when looking at the overall effects of the job and sociopsychological stresses on job satisfaction, organizational commitment, and leaving intention, work autonomy was the most influencing factor of work stress levels. The level of the job stress seemed to be a prevalent impact on the leaving intention and it showed the most negative relationship that path coefficient from leaving intention to organizational commitment and also from organizational commitment to job satisfaction. Based on these findings, it can be defined that the job and socio-psychological stresses strongly influence job satisfaction, organizational commitment, and leaving intention.