• Analytical Science and Technology
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• v.27 no.6
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• pp.357-363
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• 2014

Isoprene is a one of the biogenic volatile organic compounds (BVOCs) and it is known as a source of the tropospheric ozone and formaldehyde. In addition, isoprene is a trace component of the exhaled breath and it is a potential biomarker for the diagnosis of diseases such as lung cancer. In these regards, isoprene gas standards are required for the accurate measurement of isoprene in air samples. To establish a standard for isoprene gas, gravimetric preparation and characterization of primary gas standards were studied. The primary gas standards were produced independently in 4 aluminum cylinders and concentrations were examined by GC-FID. As a result, the uncertainty of the gravimetric preparations including purity of the raw material was 0.01% and reproducibility of the preparation of independent 4 cylinders was 0.08%. The primary gas standards for isoprene showed 14 months of long-term stability. The relative expended uncertainty of 2.8% (95% of confidence level, k=1.96) was assigned to the certified value of 10 ${\mu}mol$/mol level of isoprene based on the quantitative evaluation of the purity, weighing, reproducibility, adsorption and long-term stability.

• Journal of Life Science
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• v.24 no.1
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• pp.92-97
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• 2014

Cordycepin, an active component originally isolated from the traditional medicine Cordyceps militaris, is a derivative of the nucleoside adenosine, which has been shown to possess a number of pharmacological properties, including antioxidant and anti-inflammatory activities, immunological stimulation, and antitumor effects. This study was conducted on cultured human prostate carcinoma LNCap cells to elucidate the possible mechanisms by which cordycepin exerts its anticancer activity, which, until now, has remained poorly understood. Cordycepin treatment of LNCap cells resulted in dose-dependent inhibition of cell growth and the induction of apoptotic cell death as detected by an MTT assay, cleavage of poly ADP-ribose polymerase, and annexin V-FITC staining. Flow cytometric analysis revealed that cordycepin resulted in G2/M arrest in cell cycle progression and downregulation of cyclin B1 and cyclin A expression in a concentration-dependent manner. Moreover, the incubation of cells with cordycepin caused a striking induction in the expression of the cyclin-dependent kinase (CDK) inhibitor p21Waf1/Cip1 without affecting the expression of the tumor suppressor p53. It also resulted in a significant increase in the binding of CDK2 and CDC2 to p21. These findings suggest that cordycepin-induced G2/M arrest and apoptosis in human prostate carcinoma cells is mediated through p53-independent upregulation of the CDK inhibitor p21.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.3
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• pp.255-264
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• 2022

The active ingredients of Napttegi Kong(GML, Glycine max landrace), a type of native rare soybeans, were identified, and an ultrasonic extraction method was introduced as an eco-friendly extraction method. Through the component analysis of the Napttegi Kong extract, the epicatechin, which was not found in conventional soybeans, was identified. For effective extraction using ultrasonic, the main extraction conditions were optimized using the response surface analysis method. Through the Box-Behnken design process, 15 experiments were conducted with the extraction temperature, the ratio of extraction solvent/solution, and extraction time as key independent variables. A quadratic regression equation for the two dependent variables, epicatechin content and total isoflavone content, was derived, and the coefficients of determination were found to be high as R² = 0.9939 and R² = 0.9844, respectively, confirming that the correlation showed high significance. The extraction conditions satisfying the maximum expectations of these two dependent variables were predicted. to be 40.4℃ of extraction temperature, 19.3 times of extraction solvent/solution, and 91 sec of extraction time. The expected value and the actual experimental value of the epikatechin content and the total isoflavone content were similar, so it was confirmed that this experimental method is a highly reliable optimization model.

• International Journal of Computer Science & Network Security
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• v.22 no.9
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• pp.95-102
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• 2022

The article considers the fundamentalization of education in improving the future specialists professional training with usage of multimedia technologies by various scientists. Various points of view and approaches to defining the concepts of fundamentalization of education and multimedia technologies are identified. The concept of fundamentalization of professional training of a future specialist is based on the goals and functions of fundamentalization and - on the ways and means of achieving it, etc. Most authors agree only in their views that the fundamentalization of education is aimed at improving the quality of education and the education of the individual. Others involve the formation of a culture and worldview, increasing the creative and intellectual potential, forming the professional competence of a specialist and the potential for further education, and so on. The term multimedia refers to interactive systems that provide processing of moving and still video images, animated graphics, high-quality audio and speech. It is found out that professional training of a specialist by means of multimedia technologies includes not only the activities of the teacher and student, which form the learning process, but also the independent activity of the subject, self-development, assimilation of experience by the subject through analysis, comprehension and transformation of the field of activity in which he is included. It is revealed through the implementation of which approaches to the fundamentalization of higher professional education, it becomes possible to fully present theoretical training courses and effectively pass practical training by students, which contributes to improving the quality of training of future specialists in higher education institutions. Theoretical analysis of scientific views indicates a fairly serious attention of scientists to the problem of professional readiness of specialists and the possibility of higher educational institutions in preparing for it. At the same time, professional readiness is considered from different positions: as an active state of a person, which manifests itself in activity; as a result of activity; as goals of activity; as a quality that characterizes the attitude to solving professional problems and social situations; as a prerequisite for purposeful activity; as a form of activity of the subject; as an integral formation of personality; as a component of socio-professional culture; as a complex professionally significant neoplasm of the individual.

• Journal of Korean Society of Forest Science
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• v.108 no.3
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• pp.429-439
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• 2019

The objectives of this study were to gauge the extent of the forestry business through establishing the definition of forestry industry from the perspective of economic convergence and to analyze key components that affect each growth phase of a forestry business entity by classifying them. A total of 1,397 "sixth-sector industry" management entities were certified by the Ministry of Agriculture, Food, and Rural Affairs in South Korea from 2012-2017. Of these, 259 (18.5%) were in the forestry sector. In this study, the 259 forestry management entities were further classified into three phases based on sales distribution: entrance, development, and maturity. The entrance phase (<100 million KRW), development phase (>100 million and <1 billion KRW), and maturity phase (>1 billion KRW) constituted 33.2%, 55.4%, and 12.4% of the total 259 entities, respectively. The results showed that most of the management entities were either in the entrance or development phases, and only a small portion was in the maturity phase. To identify the key variables that affect each of the phases, chi-square analysis was used. We designed the "sixth-sector industry" type as an independent variable, whereas selected region, business organization, manager age group, forest product, processing type, and service type were designated as dependent variables. The results of the analysis showed that the processing and service types influenced all three developmental phases. Moreover, as the phase advanced, processing type showed a higher proportion of health-functional ingredients, such as powder or extract from forest products, which enable to develop and produce a variety of products. Service type also changed from simple experience to integrated experience tourism and finally to tourism education. Distribution and sales channel also turned out to be a significant factor during the development phase. This study provides the basic information needed to guide government support in the implementation of a formal forestry business through convergence as well as to increase the efficiency of business management.

• Korean Journal of Health Psychology
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• v.14 no.2
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• pp.277-292
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• 2009

This study investigated the responses of the autonomic nervous system of individuals with Type D personality during an acute stressful situation. Twenty-three female students of Type D personality and 23 female students with non-Type D personality. Stroop Color-Word Task was used to induce a stressful situation, heart rate variability (HRV) was used to measure the responses of the autonomic nervous system during the baseline, acute stress, recovery periods. To analyze the data, the repeated measures analysis of variance was used to compare the autonomic nervous system of the Type D group to that of the non-Type D group. Regression analysis is used to determine if the Type D scale and stress vulnerability predicted the activities of the autonomic nervous system during the baseline period. The results of this study demonstrated that the Type D group's normalized low frequency (LF norm) and ratio of low frequency to high frequency (LF/HF ratio) were higher than those for the non-Type D group, while its normalized high frequency (HF norm) was lower than that for the non-Type D group in all three periods. There were no statistically significant differences among the three periods in terms of LF norm, HF norm, and LF/HF ratio in the Type D group. The study demonstrated that the total scores of the Type DS-14 and scores of social inhibition and negative affect were independent predictors of LF norm and HF norm during the baseline. The Type D group showed increased activation of the sympathetic nervous system and/or decreased activation of the parasympathetic nervous system. These results support the hypothesis that the Type D personality is vulnerable to the stress. Also, the highly activated sympathetic and/or lowly activated parasympathetic nervous systems, which were observed in the Type D group during the baseline, indicated that the Type D individual is susceptible to psychosomatic disorders.

• Convergence Security Journal
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• v.8 no.3
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• pp.83-92
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• 2008

In respect complication of group and period, the sales of retail trade is composed of various factors. This paper studies focus on estimating the determinants of the sales of retail trade. The volume of analysis consist of 7 groups. Analyzing period be formed over a 36 point(2005. 1$\sim$2007. 12). In this paper dependent variable setting up sales of retail trade, explanatory(independent) variables composed of composite stock price index, the number of the consumer's online buying behavior company, the coincident composite index, the index of trading price of APT, employment rate, an average of the rate of operation(the manufacturing industry), the consumer price index. The result of estimating the determinants of sales of retail trade provides empirical evidences of significance positive relationships between the coincident composite index, the index of trading price of APT, employment rate, an average of the rate of operation(the manufacturing industry). However this study provides empirical evidences of significance negative relationships between the consumer price index. The explanatory variables, that is, composite stock price and the number of the consumer's online buying behavior company, are non-significance variables. Implication of these findings are discussed for content research and practices.

• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.2
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• pp.114-118
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• 2017

Purpose: The aim of this study was to investigate the effects of a titanium component for the zirconia abutment in the internal connection implant system on screw loosening under thermocycling conditions. Materials and Methods: Internal connection titanium abutments and external connection zirconia abutments with titanium sockets were connected respectively to screw-shaped internal connection type titanium implants with 30 Ncm tightening. These implant-screw-abutment assemblies were divided into two groups of five specimens each; titanium abutments as control and zirconia abutments with titanium sockets as experimental group. The specimens were subjected to 2,000 thermocycles in water baths at $5^{\circ}C$ and $55^{\circ}C$, with 60 seconds of immersion at each temperature. The removal torque values (RTVs) of the abutment screws of the specimen were measured before and after thermocycling. RTVs pre- and post-thermocycling were investigated in statistics. Results: There was not screw loosening identified by tactile and visual inspection in any of the specimens during or after thermocycling. The mean RTV difference for the control group and the experimental group were $-1.34{\pm}2.53Ncm$ and $-1.26{\pm}2.06Ncm$, respectively. Statistical analysis using an independent t-test revealed that no significant differences were found in the mean RTV difference of the groups (P > 0.05). Conclusion: Within the limitations of this in vitro study, the titanium socket for the zirconia abutment did not show a significant effect on screw loosening under thermal stress compared to the titanium abutment in the internal connection implant.

• Journal of Preventive Medicine and Public Health
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• v.21 no.1 s.23
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• pp.195-206
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• 1988

Two major issues of the blood bank management are quality assurance and inventory control. Recently, in Korea blood donation has gained popularity increasingly to allow considerable improvement of the quality assurance with respect to blood collection, transportation, storage, component preparation skills and hematological tests. Nevertheless the inventory control, the other issue of blood bank management, has been neglected so far. For the supply of blood by donation barely meets the demand, the blood bank policy on the inventory control has been 'the more the better.' The shortage itself by no means unnecessitate inventory control. In fact, in spite of shortage, no small amount of blood is outdated. The efficient blood inventory control makes it possible to economize the blood usage in the practice of state-of-the-art medical care. For the efficient blood inventory control in Korean hospitals, this tudy is to develop formulae forecasting the standard blood inventory level and suggest a set of policies improving the blood inventory control. For this study informations of $A^+$ whole bloods and packed cells inventory control were collected from a University Hospital and the Central Blood Bank of the Korean Red Cross. Using this informations, 1,461 daily blood inventory records were formulated.48 varieties of blood inventory control environment were identified on the basis of selected combinations of 4 inventory control variables-crossmatch, transfusion, inhospital donation and age of bloods from external supply. In order to decide the optimal blood inventory level for each environment, simulation models were designed to calculate the measures of performance of each environment. After the decision of 48 optimal blood inventory levels, stepwise multiple regression analysis was started where the independent variables were 4 inventory control variables and the dependent variable was optimal inventory level of each environment. Finally the standard blood inventory level decision rule was developed using the backward elimination procedure to select the best regression equation. And the effective alternatives of the issuing policy and crossmatch release period were suggested according to the measures of performance under the condition of the standard blood inventory level. The results of this study' were as follows ; 1. The formulae to calculate the standard blood inventory level($S^*$)was $S^*=2.8617X(d)^{0.9342}$ where d is the mean daily crossmatch(demand) for a blood type. 2. The measures of performace - outdate rate, average period of storage, mean age of transfused bloods, and mean daily available inventory level - were improved after maintenance of the standard inventory level in comparison with the present system. 3. Issuing policy of First In-First Out(FIFO) decreased the outdate rate, while Last In-First Out(LIFO) decreased the mean age of transfused bloods. The decrease of the crossmatch release period reduced the outdate rate and the mean age of transfused bloods.

• Korean Security Journal
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• no.41
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• pp.123-151
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• 2014

The purpose of this study was focused on the relationship between private guards' job embeddedness and dual commitment. In this study, job embeddedness is selected as an independent variable and dual commitment is selected as a dependent variable one. job embeddedness was divided into three sub-factors such as "fit", "links", and "sacrifice", and dual commitment is again composed with organizational commitment, and career commitment. Moreover sex, age, academic background, service period, and income were selected as a control variable. To test the hypotheses, survey data from private guards in Kyungpook are collected and analyzed. Principal component method is used to see which items cluster together in each factor and to calculate factor scores. Multiple regression analysis identifies several factors which have significant effects on dual commitment. Key finding can be summarized as follow. Fist, the factor of "fit" have significant effects on organizational commitment, and career commitment. Second, the factor of "links" have significant effects on organizational commitment, and career commitment. Third the factor of "sacrifice" have significant effects on organizational commitment, and career commitment. Finally, when all the variables with significant effects are included in the final model, "links" disappear, while "fit" and "sacrifice" remain statistically significant. Based on these finding, this study suggests some policy issues to promote private guards' dual commitment.