• Journal of Life Science
• /
• v.25 no.4
• /
• pp.433-440
• /
• 2015

Several studies suggest that regular consumption of walnuts may have beneficial effects against oxidative stress-mediated disease such as cancer. The present study reports the total phenolic and flavonoid contents, together with the antioxidant and antibacterial activities of several solvent extracts (methanol, n-hexane, ethyl acetate, n-butanol, and water) obtained from walnut (Juglans regia L.) green husk. MIC (minimal inhibitory concentration) values of the walnut extracts for 8 human pathogenic bacteria strain were determined using agar dilution method. Antioxidant activity of extracts were assessed using DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS (2,2’-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid)) assays, EC₅₀ of DPPH and ABTS scavenging activities, and determination of total phenolic and flavonoid content and its correlation with DPPH and ABTS scavenging capacities. Among the six extracts, ethyl acetate extract (EtOAc Ex) showed the highest antimicrobial activity at 3.2 mg/ml of MICs against Staphylococcus aureus SG511. Total flavonoids and polyphenol contents of EtOAc Ex were 42.48 mg of quercetin equivalents (QE)/g and 223.25 mg of gallic acid equivalents (GAE)/g respectively. The highest antioxidative potential was shown by the sample extracted with EtOAc Ex (EC₅₀=13.43 μg/ml for DPPH and EC₅₀=41.83 μg/ml for ABTS radical scavenging activity assay). These results showed that J. regia green husk extracts can be used as an easily accessible source of natural antibacterial agents and natural antioxidants.

• KDI Journal of Economic Policy
• /
• v.12 no.2
• /
• pp.51-79
• /
• 1990

Research on technical efficiency, an important dimension of market performance, had received little attention until recently by most industrial organization empiricists, the reason being that traditional microeconomic theory simply assumed away any form of inefficiency in production. Recently, however, an increasing number of research efforts have been conducted to answer questions such as: To what extent do technical ineffciencies exist in the production activities of firms and plants? What are the factors accounting for the level of inefficiency found and those explaining the interindustry difference in technical inefficiency? Are there any significant international differences in the levels of technical efficiency and, if so, how can we reconcile these results with the observed pattern of international trade, etc? As the first in a series of studies on the technical efficiency of Korea's manufacturing industries, this paper attempts to answer some of these questions. Since the estimation of technical efficiency requires the use of plant-level data for each of the five-digit KSIC industries available from the Census of Manufactures, one may consture the findings of this paper as empirical evidence of technical efficiency in Korea's manufacturing industries at the most disaggregated level. We start by clarifying the relationship among the various concepts of efficiency-allocative effciency, factor-price efficiency, technical efficiency, Leibenstein's X-efficiency, and scale efficiency. It then becomes clear that unless certain ceteris paribus assumptions are satisfied, our estimates of technical inefficiency are in fact related to factor price inefficiency as well. The empirical model employed is, what is called, a stochastic frontier production function which divides the stochastic term into two different components-one with a symmetric distribution for pure white noise and the other for technical inefficiency with an asymmetric distribution. A translog production function is assumed for the functional relationship between inputs and output, and was estimated by the corrected ordinary least squares method. The second and third sample moments of the regression residuals are then used to yield estimates of four different types of measures for technical (in) efficiency. The entire range of manufacturing industries can be divided into two groups, depending on whether or not the distribution of estimated regression residuals allows a successful estimation of technical efficiency. The regression equation employing value added as the dependent variable gives a greater number of "successful" industries than the one using gross output. The correlation among estimates of the different measures of efficiency appears to be high, while the estimates of efficiency based on different regression equations seem almost uncorrelated. Thus, in the subsequent analysis of the determinants of interindustry variations in technical efficiency, the choice of the regression equation in the previous stage will affect the outcome significantly.

• Korean Security Journal
• /
• no.42
• /
• pp.7-36
• /
• 2015

This study aims at analyzing difference of social Security network, Community unity and local government trust according to socio-demographical features, exploring the relation of social Security network, Community unity and local government trust according to socio-demographical features, presenting results between each variable as a model and verifying the property of mutual ones. This study sampled general citizens in Gwangju for about 15 days Aug. 15 through Aug. 30, 2014, distributed total 450 copies using cluster random sampling, gathered 438 persons, 412 persons of whom were used for analysis. This study verified the validity and credibility of the questionnaire through an experts' meeting, preliminary test, factor analysis and credibility analysis. The credibility of questionnaire was ${\alpha}=.809{\sim}{\alpha}=.890$. The inout data were analyzed by study purpose using SPSSWIN 18.0, as statistical techniques, factor analysis, credibility analysis, correlation analysis, independent sample t verification, ANOVA, multi-regression analysis, path analysis etc. were used. the findings obtained through the above study methods are as follows. First, building a social Security network has an effect on Community institution. That is, the more activated a, the higher awareness on institution. the more activated street CCTV facilities, anti-crime design, local government Security education, the higher the stability. Second, building a social Security network has an effect on trust of local government. That is, the activated local autonomous anti-crime activity, anti-crime design. local government's Security education, police public oder service, the more increased trust of policy, service management, busines performance. Third, Community unity has an effect on trust of local government. That is, the better Community institution is achieved, the higher trust of policy. Also the stabler Community institution, the higher trust of business performance. Fourth, building a social Security network has a direct or indirect effect on Community unity and local government trust. That is, social Security network has a direct effect on trust of local government, but it has a higher effect through Community unity of parameter. Such results showed that Community unity in Gwangju Region is an important factor, which means it is an important variable mediating building a social Security network and trust of local government. To win trust of local residents, we need to prepare for various cultural events and active communication space and build a social Security network for uniting them.

• Journal of Society of Preventive Korean Medicine
• /
• v.5 no.1
• /
• pp.41-56
• /
• 2001

Overview: The purpose of this study was to evaluate the determinants on the correlation between constitution and health promoting lifestyle profile on the workers. Also, the questionnaire on the HPLP (health promoting lifestyle profile) of Walker(1987) and Sa-sang constitution of Lee(l894) were utilized Methods: Data from a representative sample of 652 workers were analyzed Pearson's chi-square test analysis was utilized to test the explanatory causal model and to determine the direct and indirect effects of independent variables on quality of life. Results: Constitutional distribution among exposed group, were Tae-eum In(43.7%), So-eum In(33.6%), and So-yang In(22.7%). The degree of the subjects practicing health promoting lifestyle, on a scale of 1 to 4, is an average of 2.62, personal relations 2.94, self-realization 2.86, stress management 2.71, nutrition 2.68, responsibility for health 2.37, and exercise 2.21, with personal relations earning the highest points and exercise the lowest As for factors influencing health promoting lifestyle, there is significant difference between sex and age. That is female and higher age. On the difference between constitution and health promoting lifestyle, Tae-eum In is the highest all area except personal relations. So-eum In is the lowest all area except responsibility for health. Conclusions: Tae-eum In totally do health promoting lifestyle well but So-eum In relatively not. On the Study we used the HPLP(health promoting lifestyle profile) on the premise that each person's daily life, the attitude and the practice level to the health have an influence on the health. So in the constitution there is a little differences in the consideration and the practice level and health condition will be different. On this study we finish up by knowing about the health promoting lifestyle. But on next time we will have to go on studying about the sign and the comparison with the result of western and oriental medical health examination to the each constitution on carrying out continuously oriental medical health examination.

• Korean Journal of Remote Sensing
• /
• v.25 no.4
• /
• pp.339-357
• /
• 2009

The Saemangeum Reclamation Project was launched as a national project in 1991 to reclaim a large coastal area of 401 km$^2$ by constructing a 33-km long dyke. The final dyke enclosure in April 2006 has transformed the tidal flat into lake and land. The dyke construction has abruptly changed not only the estuarine tidal system inside the dyke, but also the coastal marine environment outside the dyke. In this study, we investigated the spatial change of SST distribution using the Landsat-5/7 and NOAA data before and after the dyke completion in the Saemangeum area. Satellite-induced SST was verified by compared with the various in situ measurements such as tower, buoy, and water sample. The correlation coefficient resulted in above 0.96 and RMSE was about 1$^{\circ}C$ in all data. 38 Landsat satellite images from 1985 to 2007 were analyzed to estimate the temporal and spatial change of SST distribution from the beginning to the completion of the Samangeum dyke's construction. The seasonal change in detailed spatial distribution of SST was measured, however, the estimation of change during the Saemangeum dyke's construction was hard to figure out owing to the various environmental conditions. Monthly averaged SST induced from NOAA data from 1998 to 2007 has been analyzed for a complement of Landsat's temporal resolution. At the inside of the dyke, the change of SST from summer to winter was large due to the relatively high temperature in summer. In this study, multi-sensor thermal remote sensing is an efficient tool for monitoring the temporal and spatial distribution of SST in coastal area.

• Korea journal of population studies
• /
• v.35 no.2
• /
• pp.209-232
• /
• 2012

The purposes of this study is to calculate the gender-based Life Expectancy and Disability Free Life Expectancy of 65-year-olds in accordance with the regions of 16 in Korea based on the years 2005 and 2010 by using the Sullivan method. We used the Census in 2005, 2010, the Korea National Statistical Office(10% sample). We also reviewed examining the changes in LE and DFLE and understanding the relevance between the DFLE of 65-year-olds of the year 2010 and related factors. As a result of this study, it was shown that the LE of the group of all 65-year-old in Korea increased from 18.15 years in 2005 to 19.75 years in 2010 and DFLE increased from 11.41 years in 2005 to 11.64 years in 2010. Regionally, the highest LE for total of 65-year-olds was found to be the entire Jeju area and DFLE was the highest in the city of Seoul. And the highest LE and the highest DFLE for 65-year-old male were found to be in the city of Seoul. Regarding the regional LE of 65-year-old female, both in 2005 and 2010 Jeju area was seen to be the highest. The results of a correlation analysis showed that the DFLE of 65-year-olds in 2010 was found to be increasing with high LE and high population density and in regions with low average temperatures, low number of beds and low age standardized death rates of malignant neoplasms and circulatory disease.

• Korean Journal of Psychosomatic Medicine
• /
• v.23 no.2
• /
• pp.93-99
• /
• 2015

Objectives : The purpose of this preliminary study was to investigate job stress and stress coping strategy among workers in a regional statistics office. Methods : A total of 133 workers in regional statistics office participated in this study and they were divided into two groups, survey group(n=109) and support group(n=24) depending on relation to statistical survey task. They were asked to respond to Short Form of Korean Occupational Stress Scale(KOSS-SF) and Stress Coping Strategy(SCS) to investigate sociodemographic characteristics, job stress, and stress coping strategy. Results : The proportion of the 133 participants in the sample was 59(44.4%) of men, 74(55.6%) of women. There were no significant differences in KOSS-SF scores in relation to age, sex, education, and marital status, while the KOSS-SF scores were significantly different between the two groups. In regard to the subscales of KOSS-SF, the two groups had significant differences in insufficient job control, interpersonal conflict, job insecurity, and organization system. In addition, the total score of KOSS-SF had a negative correlation with problem-focused coping strategy and social support coping strategy of SCS. Conclusions : Our results suggest that workers of survey group had more job stress compared to those who works in support group in regional statistical office. In addition, in comparison with workers of support group, both men and women of survey group get stressed when they were confronted with interpersonal conflicts. Our results suggest that using problem-focused coping and social support coping strategy lowers job stress.

• Journal of the Korean GEO-environmental Society
• /
• v.20 no.2
• /
• pp.41-48
• /
• 2019

Soil compaction is one of the most important activities in the area of civil works, including road construction, airport construction, port construction and backfilling construction of structures. Soil compaction, particularly in road construction, can be categorized into subgrade compaction and roadbed compaction, and is significant work that when done poorly can serve as a factor causing poor construction due to a lack of compaction. Currently, there are many different types of compaction tests, and the plate bearing test and the unit weight of soil test based on the sand cone method are commonly used to measure the degree of compaction, but many other methods are under development as it is difficult to secure economic efficiency. For the purpose of this research, a portable penetration meter called the Free-Fall Penetration Test (FFPT) was developed and manufactured. In this study, a homogeneous sample was obtained from the construction site and soil was classified through a sieve analysis test in order to perform grain size analysis and a specific gravity test for an indoor test. The principle of FFPT is that the penetration needle installed at the tip of an object put into free fall using gravity is used to measure the depth of penetration into the road surface after subgrade or roadbed compaction has been completed; the degree of compaction is obtained through the unit weight of soil test according to the sand cone method and the relationship between the degree of compaction and the depth of the penetration needle is verified. The maximum allowable grain size of soil is 2.36 mm. For $A_1$ compaction, a trend line was developed using the result of the test performed from a drop height of 10 cm, and coefficient of determination of the trend line was $R^2=0.8677$, while for $D_2$ compaction, coefficient of determination of the trend line was $R^2=0.9815$ when testing at a drop height of 20 cm. Free fall test was carried out with the drop height adjusted from 10 cm to 50 cm at increments of 10 cm. This study intends to compare and analyze the correlation between the degree of compaction obtained from the unit weight of soil test based on the sand cone method and the depth of penetration of the penetration needle obtained from the FFPT meter. As such, it is expected that a portable penetration tester will make it easy to test the degree of compaction at many construction sites, and will lead to a reduction in time, equipment, and manpower which are the disadvantages of the current degree of compaction test, ultimately contributing to accurate and simple measurements of the degree of compaction as well as greater economic feasibility.

• Korean Journal of Clinical Laboratory Science
• /
• v.50 no.4
• /
• pp.449-456
• /
• 2018

Cervical cancer is the fourth most frequently diagnosed cancer in women worldwide. In lower Human Development Index countries, it has the second highest incidence and mortality among cancer in women. Therefore, better diagnosis and treatment systems are needed. Among them, estrogen receptor alpha ($ER-{\alpha}$) mRNA expression has been analyzed with RT-qPCR since several studies reported that $ER-{\alpha}$ is necessary in the maturation of the uterus and is related to cervical cancer. In this study, $ER-{\alpha}$ quantitative analysis was performed on various lesions and normal tissue samples. Based on the receiver operating characteristic (ROC) curve, its sensitivity and specificity were 85% and 75%, respectively, showing higher or similar results to those of conventional HPV tests. In addition, its expression level was analyzed with clinical information. With regression analysis, the R square value between the $ER-{\alpha}$ mRNA expression level and menopause status was 0.5041, indicating a strong correlation. This study was performed as part of a pilot study and suggests that $ER-{\alpha}$ is related to carcinogenesis. Future studies will examine other hormones and menopausal factors with a larger sample size.

• Journal of Food Hygiene and Safety
• /
• v.34 no.3
• /
• pp.283-289
• /
• 2019

This study was performed to monitor the residual pesticides in agricultural products used in school foodservice in the Gwangju metropolitan area. Risk assessment was also carried out based on the amount of agricultural products consumed. A total of 320 agricultural products supplied to schools in Gwangju were analyzed from 2015 to 2017. The pre-treatment and residual pesticide analysis of these products was conducted in accordance with the second method for multi-residue analysis of pesticides in the Korean food code. The hazard index was calculated by dividing the estimated daily intake (EDI) of pesticides by the acceptable daily intake (ADI). The linearity correlation coefficient for the calibration curve was 0.9923 to 1.0000, LOD 0.004 to 0.019 mg/kg, LOQ 0.012 to 0.057 mg/kg, and recovery was 79.1 to 100.2%. Residual pesticides were detected in 18 (5.6%) of 320 agricultural products used for school foodservice, and one sample of sweet potato stem (0.3%) exceeded the maximum residual limit (MRL). The detection frequency for chili peppers and bell peppers was higher than that for other agricultural products. The frequently-detected pesticides were boscalid and acetamiprid. These results showed that residual pesticide management is needed for chili pepper, bell pepper and sweet potato stem among agricultural products supplied to schools. The hazard index of bifenthrin in sweet potato stem showed the highest (64.18%), and the other pesticides were 0.03-8.23%. These results indicated that agricultural products supplied to schools in Gwangju were safe for consumption. To minimize the intake of residual pesticides, it is necessary to not only thoroughly wash agricultural products but to also ensure the expanded supply of products that are pesticide-free.