• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.7
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• pp.1-8
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• 2019

The primary purposes of this study are to understand a fundamental effects of electro-deposition on reinforcing steel in saturated Ca(OH)2 electrolyte, and evaluate the corrosion rates of rebars under cyclic 3wt.%NaCl immersion and dry corrosion environment. The three cement mortar specimens with cover thickness 5, 10 and 30mm, were prepared in the experiment. To monitor the corrosion rates of rebars in mortar, the three cement mortar specimens were exposed to 110 wet-drying cycles(8-hour-immersion in 3wt.%NaCl and 16-hour-drying in a room temperature) in the laboratory. During the wet-dry cycles, the polarization resistance, Rp, and solution resistance, Rs, were continuously measured. The instantaneous corrosion rates of rebars on the effect of electro-depositing with sat. Ca(OH)2 electrolyte were estimated from obtained R-1p and degrees of wetness were estimated from Rs values. From the experimental results, the corrosion rates of rebars were greatly accelerated by wet/dry cycles. During the mortars exposed to drying condition, the large increases in the corrosion rates were showed at all rebar surfaces in three mortar specimen, attributed from the accelerated reduction rates of dissolved oxygen in drying process. However, the corrosion rates on rebar surface electrochemically deposited with sat. Ca(OH)2 electrolyte showed the clear decreases, caused by calcium deposits in the porous rust layer.

• Management & Information Systems Review
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• v.39 no.2
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• pp.163-179
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• 2020

Recently, impact investment has attracted attention all over the world. This is intended to effectively solve problems by combining private capital and various financial techniques with social and environmental needs, as it is recognized that it is difficult to solve social and environmental problems. Impact investment means a mixture of financial, social, and environmental aspects. This refers to an investment focused on such a blended value, through which it simultaneously achieves financial and social values such as return on investment. The purpose of this study is to study whether impact investment, which has become a new issue, is actually applicable in Korea. This study first considers the concept and method of impact investment, and a prior study on social enterprises and impact investment that pursue social values. In particular, after analyzing in detail the social performance-related bonds (SIB) and operational cases, we intend to explore the possible applicability of impact investment to Korea. The results and implications of this study are, first, changes in the government's attitude toward impact finance. The government should entrust innovative public works to market-proven service providers to enhance the professionalism and efficiency of public service projects. Second, the legal system must innovate. Impact investment should provide an institutional foundation to pursue social problem solving simultaneously, not maximizing financial performance. Third, when investing in public works in the private sector, impact investment must clearly demand social performance and clarify the evaluation accordingly. The project execution process should create an impact environment that is more free and active.

• Journal of Plant Biotechnology
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• v.44 no.2
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• pp.171-177
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• 2017

A callus-mediated regeneration protocol for sea-milkwort, an endangered coastal plant species in South Korea, is reported here. The explants of in vitro-plantlets generated from a node culture revealed distinguishable responses in callus induction depending on genotype, explant source, light condition, and 2,4-D concentration. Especially, continuous darkness exclusively facilitated callus induction from explants prior to other treatments. The calli initiated on the media with 2,4-D ranging from 0.1 mg/L to 3.0 mg/L in the dark vigorously proliferated when subcultured on the same media in continuous darkness. Given 1.0 mg/L zeatin in addition to darkness to the calli of the 'Pistachio' genotype, normal adventitious shoots were only regenerated from nodular structures that formed earlier from the calli at the frequency of 24.4 percent. Regenerated shoots easily grew into plantlets with roots and green color on a phytohormone-free MS medium under lighted condition, that were used for node culture as plant materials. Node culture effectively multiplied plantlets in accordance with protocol by Bae et al. (2016). Acclimatized plantlet clusters developed mature plant clusters under inland environment, followed by flowering the following April. Results were merged with node culture protocol suggested by Bae et al. (2016), which, as an in vitro propagation system for sea-milkwort, may contribute to natural habitat restoration.

• Korean Journal of Agricultural Science
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• v.30 no.2
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• pp.175-183
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• 2003

Fruit and vegetables are subjected to complex dynamic stresses in the transportation environment. During a long journey from the production area to markets, there is always some degree of vibration present. Vibration inputs are transmitted from the vehicle through the packaging to the fruit. Inside, these cause sustained bouncing of fruits against each other and container wall. These steady state vibration input may cause serious fruit injury, and this damage is particularly severe whenever the fruit inside the package is free to bounce, and is vibrated at its resonance frequency. The determination of the resonance frequencies of the fruit and vegetables may help the packaging designer to determine the proper packaging system providing adequate protection for the fruit, and to understand the complex interaction between the components of fruit when they relate to expected transportation vibration inputs. Instrumentation and technologies are described for determining the vibration response characteristics of the fruits with frequency range 3 to 150 Hz. The computer program for controlling the vibration exciter and the function generator and for measuring the vibration response characteristics of the fruits was developed. The resonance frequency of the pear ranged from 64.5 to 72.2 Hz and the amplitude at resonance was between 1.78 and 2.21 G-rms. The resonance frequency and amplitude at resonance decreased with the increase of the sample mass, and they were slightly affected by mechanical properties such as bioyield deformation and rupture deformation. Regression analysis was performed among the relatively high correlated parameters from the results of correlation coefficient analysis.

• Journal of Dairy Science and Biotechnology
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• v.33 no.3
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• pp.209-214
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• 2015

This study was carried out to investigate the effects of different milking systems (AMS, automatic milking system and CMS, conventional milking system) and of supplemental fat feeding on milk composition and milk fat characteristics. The composition, MFG (milk fat globule) size, fatty acids (FAs), and free fatty acids (FFAs) of the milk from 4 AMS and 4 CMS dairy farms were analyzed on the basis of the milking system and feeding of protected fat. The milking system did not affect milk composition, MFG size, and milk FAs, but FFA content of AMS milk were significantly higher than that of CMS milk. Feeding of protected fat resulted in the production of milk much higher in LCFAs (long chain FAs); however, the milk composition was not affected by fat supplementation. Cows administered protected fat supplements produced milk containing MFGs with a large average diameter.

• Research in Community and Public Health Nursing
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• v.10 no.1
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• pp.93-105
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• 1999

Recently, Korean health care industry managers are paying more attention to customer oriented service, the rationalization of business administration, and quality control of service to adjust their business to outer environment since IMF bailout program. They are focusing on the cost reduction through remodeling the size and structure of man power, viz. labor flexibility. Nurses are not free from this juncture and contingent nurses are increasing fast. This article intends to verify the actual condition of two types of contingent nurses -part-time nurses and internship nurses-and to compare their job satisfaction to provide basic resource for efficient management of nurse man power. The concrete goals of this article are; Firstly, to verify the actual condition of their employment. Secondly, to compare their job satisfaction. And Thirdly, to the relation between employment condition and job satisfaction. To accomplish these research goals, a statistical survey was executed, in which 384 questionnaires - 66 for manager nurses, 318 for contingent nurses-were given to nurses working at 66 general hospitals-which have at least 100 beds-in Seoul. Among them, 121 questionnaires-of 28 general hospitals-were returned. Then, the data coded and submitted to mean, standard deviation, T-test, variance analysis (ANOVA), correlation analysis, multiple regression analysis with SAS program. The research results of the contingent nurses are followings: 1. Two types of contingent nurses shows similar age spans: they are mostly 21 - 30 years old and unmarried. But internship nurses have high level of educational career. Part - time nurses spread at general beds, out -patient part, intensive care part, operation part, etc, but internship nurses work mostly at general beds. 2. Two groups shows difference in actual employment condition: average employment career of part -time nurses is 7.0 months but internship nurses' is 2.0 months: average duty-on days per month of part - time nurses are 23.7 days but internship nurses' are 24.8 days. But there are little difference in average working time per day: 7.7 hours for part -time nurses and 0 hours for internship nurses. 3. The average wage per month for part -time nurses is 836,026 won but for internship nurses is 557,428 won-66.7% of part-time nurses'. Both groups are enjoying little additional pay. 4. Both groups are getting job not so much through advertisement of newspaper or hospitals as through acquainted person or college. 5. Both groups show very high level of job satisfaction: 3.2195 for part -time nurses and 3.2881 for internship nurses. But they show very low satisfaction on payment level compared with other categories and two groups show meaningful difference(P<.0001). 6. The multiple regression test reveals the factors related with job satisfaction: wage level, working part(OR or ICU), age, job career, and motive of contingent job-taking('because I can take care of family duties at the same time') influence positively: motive of contingent job-taking('because I can work regularly without alternation') influences negatively.

• Journal of the Korean Geosynthetics Society
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• v.14 no.2
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• pp.89-94
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• 2015

In this study, the mixed soil with an optimum mixed ratio was suggested in order to recycle the powdered sludge of basalt in Jeju Island as the impermeable liner materials. As the results of soil laboratory tests, the grain size of the powdered sludge of basalt is less than 0.1mm and the powdered sludge was classified into ML or CL category in accordance with the Unified Soil Classification System (USCS). Also, the grain size of natural soils is ranged from 0.1 mm to 10 mm and the soils were classified into SW category in USCS. To select the optimum mixed ratio of powdered sludge, the variable permeability test was performed to various mixed soils with different powdered sludge amount under both optimum compaction and field conditions. As the results of permeability tests, the coefficient of permeability of mixed soils was decreased with increasing the mixed ratio of powdered sludge, and the mixed soil with mixed ratio of 60% has the minimum coefficient of permeability. Therefore, the optimum mixed ratio of powdered sludge is 60% for recycling the powdered sludge of basalt as the impermeable liner materials.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.6
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• pp.1090-1097
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• 2000

The aim of this study was to investigate the relationships among energy intakes, macronutrient intakes, macronutrient compositions, anthropometric and biochemical variables in natural environment of free-living female college students. The daily energy and macronutricnt intakes were analyzed by means of 3- week dictary records. The waist circumference and insulin level were best anthropometric and bio-chemical correlates with the energy, carbohydrate and protein intakes respectively. However, there were no relationships between waist circumference and insulin verse macronutrient compositions that macro-nutrient intakes were expressed as by the percentage of daily encrgy intakes. There were no relationships between BWI, weight, perccnt body fat and fat mass vs. energy and macronutrient intakes. However, BMI was positively related to the percentage of energy from fat and inversely related to the percentage of energy from carbohydrate in their habitual diet. Triglyceride was negatively correlated to the per-centage of energy from fat and fat intakes. Significant positive correlation was also observed bctween the percentage of energy from protein and HSL-cholcsterol.

• Journal of Environmental Policy
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• v.10 no.4
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• pp.3-37
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• 2011

This paper investigates the existence of the environmental Kuznets curve (EKC) for carbon dioxide $CO_2$ emissions and its causal relationships with economic growth and openness by using time series data (1971-2006) from China (an emerging market), Korea (a newly industrialized country), and Japan (a developed country). The sample countries span a whole range of development stages from industrialized to newly industrialized and emerging market economies. The environmental consequences according to openness and economic growth do not show uniform results across the countries. Depending on the national characteristics, the estimated EKC show different temporal patterns. China shows an N-shaped curve while Japan has a U-shaped curve. Such dissimilarities are also found in the relationship between $CO_2$ emissions and openness. In the case of Korea, and Japan it represents an inverted U-shaped curve while China shows a U-shaped curve. We also analyze the dynamic relationships between the variables by adopting a vector auto regression or vector error correction model. These models through the impulse response functions allow for analysis of the causal variable's influence on the dynamic response of emission variables, and it adopts a variance decomposition to explain the magnitude of the forecast error variance determined by the shocks to each of the causal variables over time. Results show evidence of large heterogeneity among the countries and variables impacts.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.12
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• pp.1672-1681
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• 2007

Cationization is effective to complement the defects of Tencel blended fabrics by introducing new functions. For this purpose, we used chitosan, which is congenial to the human body, free of pollution, and easily reacted. Then, we compared it to the Tencel single fabrics. To perform such effective cationization, the fabrics were treated with chitosan after NaOH pretreatment and enzyme treatment thereof. After that, the fabrics were treated with a crosslinking agent and a softner. The dyeing property of the cationized Tencel blended fabrics and reactive dye, which is a type of anionic dye, show a high concentration in neutral salt and excellent repulsive power between the fabrics and the decreased dyes. The dyeing property of the chitosan treated fabrics represented better performances than that of untreated fabric in the lower concentration of neutral salt. Meanwhile, when it was dyed with certain acid dyes, the dyeing property of the chitosan treated fabrics showed better results due to the reaction of an amine group, which was introduced by chitosan treatment. Thus, the verification of the cationization of the Tencel blended fabrics was performed. The washing fastness of the Tencel blended fabrics showed a little bit better than that of the Tencel single fabric, and it represented a better performance in the dye with a reactive dye than that of an acid dye.