• Journal of Life Science
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• v.33 no.1
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• pp.82-90
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• 2023

Biological process is used worldwide to treat domestic and industrial wastewater. The process generally uses a mixed microbial culture of sludge. The growth of microorganisms in the sludge produces excess sludge from the wastewater treatment process. Some of the excess sludge is recycled as inoculum for wastewater treatment, but the rest is removed as waste from the process. As wastewater production is increasing worldwide every year, the number of wastewater treatment plants (WWTPs) is also in- creasing, resulting in the generation of large amount of waste sludge. The increasing amount of waste sludge from WWTPs has led to concerns about its management. Sludge disposal has been reported to account for 50~60% of the total operating costs of a WWTP. Sludge disintegration is a new technology that can minimize volume of waste sludge and recover useful components (e.g., P, N, and soluble organic compounds) from it. Various methods of sludge disintegration have been developed based on physical, chemical, and biological treatments or combinations of these. In this review, we focus on sludge disintegration by acid hydrolysis, which is less studied among sludge disintegration methods. Such information can be useful in the development and implementation of a new technology for better sludge treatment.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.10a
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• pp.376-378
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• 2021

According to the 2020 Global Climate Report released by the World Meteorological Organization, the average temperature of the Earth in 2019 was measured 1.1℃ higher on average than the temperature measured between 1850 and 1900 before industrialization. The change in average temperature affects the distribution of plants, and according to the vulnerability analysis paper, it can be seen that there is a change in the distribution area of plants when the average temperature rises. In this paper, to cope with these environmental changes, we propose a method of fabricating intermittent flow hydroponic smart farms using Arduino and sensors and controlling them through PCs and applications. The manufactured hydroponic smart farm identifies the farm's temperature and humidity, positive pH concentration, illumination, and water quality to check the amount of pumping, supplement LED control, sensor condition, overall management and cultivation of the farm, and grows in an appropriate environment.

• Journal of Nutrition and Health
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• v.55 no.3
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• pp.330-347
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• 2022

Folate, a water-soluble vitamin, acts as a coenzyme for one-carbon metabolism in nucleic acid synthesis and amino acid metabolism. Adequate folate nutritional status during the periconceptional period is known to prevent neural tube defects. In addition, insufficient folate intake is associated with various conditions, such as anemia, hyperhomocysteinemia, cardiovascular disease, cancer, cognitive impairment, and depression. This review discusses the rationale for the revision of the 2020 Korean dietary reference intakes for folate, and suggestions for future revisions. Based on the changes in the standard body weight in 2020, the adequate intake (AI) for infants (5-11 months) and the estimated average requirements (EARs) for 15-18 years of age were revised, but there were no changes in the recommended nutrient intakes (RNIs) and tolerable upper intake levels (ULs) for all age groups. Mean folate intake did not reach RNI in most age groups and was particularly low in women aged 15-29 years, according to the results of the 2016-2018 Korea National Health and Nutrition Examination Survey (KNHANES). The percentages of folate intake to RNI were lower than 60% in pregnant and lactating women, but serum folate concentrations were higher than those in other age groups, presumably due to the use of supplements. Therefore, total folate intake, from both food and supplements, should be evaluated. In addition, the database of folate in raw, cooked, and fortified foods should be further expanded to accurately assess the folate intake of Koreans. Determination of the concentrations of erythrocyte folate and plasma homocysteine as well as serum folate is recommended, and quality control of the analysis is critical.

• Journal of Distribution Research
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• v.12 no.3
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• pp.23-48
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• 2007

Category management has been implemented to enhance competitiveness in the food distribution industry since 2000 in Korea. This study helps to understand why suppliers achieve better or worse performance than competitors in a category. The major objective of this article is to explore which category tactics are effective to have influence on category performance when suppliers as a category captain implement category management with variety enhancer categories like shampoo, toothpaste, and detergent. The Nielsen data were analyzed using regression and Chow test. The empirical results that were varied upon the store type and market position found out which specific actions on product assortments, pricing, shelving, and product replenishment can increase category sales. Specifically, in the case of market leader in large supermarket, the significant indicators of category sales with respect to category tactics are the out-of-stock rate, the variance across brand shares, the forward inventory, and the days supply of a product. However, in the case of follower in large supermarket, the significant indicators of category sales are the variance across brand shares, the forward inventory, and the days supply of a product. On the other hand, in the case of small supermarket, the significant factors on category sales for both market leader and follower are the retail distribution rate, the variance across brand shares, the forward inventory, and the days supply of a product category. In sum, regardless of the store type and market position, dominant brands in a category, the forward inventory, and short days supply of a product improved performance in all categories. Critical difference is that the out-of-stock rate acted as a key ingredient for the market leader between large and small supermarket and the retail distribution rate for the follower between large and small supermarket. This article presents some theoretical and managerial implications of the empirical results and finalizes the paper by addressing limitations and future research directions.

• Journal of Korean Home Economics Education Association
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• v.16 no.4 s.34
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• pp.141-156
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• 2004

The purpose of this study was to examine the relationship between marital satisfaction and job performance among secondary school married female teachers. The subjects of this study were 237 married female teachers who worked in middle-and high-schools in Seoul and Gyeonggido. To gauge how they were pleased with their married lives. Lee Jeong-ryeon(1987)'s scale that was based on Synder's scale and made up for its segment about relations with family-in-law. As for job performance. Yun Gyeong-hye(2001)'s scale that was based on Son Jeong-hwan(1990)'s teacher job scale was employed. For data analyses. t-tests. ANOVAs. Scheffe tests for pairwise comparison. Pearson's correlations were utilized. The findings of this study illustrated that the marital satisfaction of the secondary school married female teachers were significantly related to their job performance. This indicated that their marital satisfaction served to enhance their job performance. and furthermore. that could be said to determine the quality of school education.

• The Journal of Engineering Geology
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• v.17 no.1 s.50
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• pp.15-25
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• 2007

In general, the life and asset casualties that occur due to landslide or slope failure in urban areas are larger than that in rural areas. In order to reduce the casualties, a slope management program is necessary to categorize slopes based on properties and to manage them systematically. The slope management system is the establishment of the data base for the geological and geotechnical factor according to slope stability, and the utilization of the data base to manage slopes. The suitable system must develop to slopes in urban area through the survey, analysis and evaluation process. Based on the above necessity, the slope management program which is applicable to slope management in an urban area has been developed at Hwangryung Mt. in Busan as a target area. The developed slope management program has various functions such as slope ID number of each slope or sub-region of a mountain, making a slope data sheet, analysis and grouping of slope stability, and establishment of a data base. The slope management program is constructed by use of GIS, and the survey, test and analysis data according to all slopes can be input and edited into the program. The program can also be utilized practically by end users due to the convenient input, edition printing, management and operation of slope data. Therefore, the slope management system has been established on the application of the developed program in Busan which is located in slope area. As the system is widely applied to other cities, the slope in urban area can be managed systematically and the slope hazards can be minimized.

• Journal of Navigation and Port Research
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• v.42 no.3
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• pp.227-236
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• 2018

The Busan New Port and its hinterland have not operated smoothly due to the complicated laws and various related organizations. Thus, many projects involving the port are not matched with its purpose of establishment. In particular, a large-scale apartment complex, which was constructed without a negotiation among the related organizations, is disturbing the port's logistics function. Also, the construction and management of every traffic facilities are conducted by various organizations due to the functions for the facilities are dispersed among them, which has given rise to chaos and responsibility-shifting. As a result, worries about the friction among the organizations and the loss of function of the port hinterland exist. This paper analyzes the problems of inter-governmental functional distributions in the construction and management of the port hinterland of the Busan New Port based on the principles (theories) of functional distribution. In addition, this paper proposes improvements for the functional distribution. The results of the analysis indicated that the functions for housing and traffic facilities were duplicated and dispersed among organizations, resulting in an unclear division of responsibilities. Finally, the paper proposed solutions for the problems: the institutionalization of an administrative conference system among related organizations, using an integrated administration for a wide area (contracting-out, association among local governments), and establishing a special-purpose local government (association among local governments, BPA).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.136-145
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• 2018

Companies that have suffered serious labor shortages are relocating their factories abroad where they can solve this problem by increasing the employment of foreign workers. Construction sites also employ foreign workers to supplement the scarce manpower, and the demand for foreign workers has been gradually increasing over time. Recently, based on discussions on whether or not to introduce foreign workers, the policy on the input of foreign workers into domestic construction sites has been shifted to exploring the actual input conditions and efficient management methods. In this study, we investigated the current status and input situation of foreign workers at the construction sites of the target area, analyzed the problems they posed from the manager's viewpoint, and derived a method of improving the utilization of foreign workers at construction sites. In order to proceed with this study, we surveyed the actual situation of the construction sites, which consisted mainly of foreign workers and domestic workers (managers), by investigating the construction sites, and conducted 1: 1 interviews to ensure the reliability of the survey. The data obtained from the survey were analyzed using the SPSS analysis program, and the response rate was analyzed for each item. As a result, various problems, such as institutional problems, communication problems, and quality deterioration due to malfunction, appeared. Therefore, this study derives an improvement plan for the efficient utilization of foreign workers by improving the institutional level related to their language education, wages and employment.

• Korean Security Journal
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• no.34
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• pp.209-232
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• 2013

As time goes by, the diversity of crime has become a serious social problem in modern society, and the policing is increasing the role of private security guards in order to fill the policing. But Private guards stressful experience to perform the actual work is exposed to various crisis situations. Then, private security guards should be management because of private security impact on job burnout. This study aims to determine the empirical work experience in the field of private security guards to cope with stress according to the degree of job burnout. The results are as follows: First, it was the negative effects of the stress coping strategies of private security guards on physical and psychological burnout, and the statistic effects of the wishes coping strategies of private security guards on physical and psychological burnout. Second, stress coping strategies of private security guards, were not found to affect the dehumanization of job burnout. Third, the center of the problem of private security guards of the ways to cope with stress coping was lacking in a static(+) affecting the accomplishment of the job burnout. Therefore, the different types of stress that may arise private security guards physically exhausted, psychologically exhausted, lack of accomplishment in the course of the private security business perform. Finally, Managers of the private security guards, job burnout occurs should be focused on the factors pre-management and co-ordination.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.1
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• pp.151-159
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• 1993

In conjunction with a vertical network. horizontal geodetic control points provide the basic framework for topographic mapping and legal survey. The design of such networks as well as the technical means for obtaining their coordinates have been changed in time, and therefore Korea National Geographic Institute has planned and observed the precise geodetic network since 1975. The aim of this study is to investigate the systematic distortions of the precise geodetic network in Korea implementing by the simultaneous adjustment. The results show that there are large discrepancies between adjusted and public coordinates in Chun-nam and Kyung-buk areas. The coordinate discrepancies are mainly due to the non-rigorous adjustment method and the disregard of the orientation unknown of the first direction for some blocks.