• Korean Journal of Social Welfare
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• v.60 no.3
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• pp.31-58
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• 2008

This study examines applying the elderly poverty labor hypothesis and skill-biased technological change hypothesis to labor force participation rate(LFPR) of older males in Korea. These hypotheses have hardly been examined on the this group. The analysis is based on the data "Summary of economically active population($1965{\sim}2007$)", "Population projection($1965{\sim}2007$)", "Report on wage structure survey($1993{\sim}2005$)" and "Korea Labor and Income Panel Study($1998{\sim}2006$)". The method employed for this study is logistic regression. The main results from this analysis are summarized in five points. Firstly, Korean older males' LFPR have been increasing since 1965 when industrialization was expanding at full steam. This trend has been different from the decreasing trend of industrialized countries. The second finding is that poor older males' LFPR is, on the average, 5.2% higher than that of non-poor older males from 1998 to 2005. The third result is that the non-elderly man has been increasingly positioned at higher grade occupations, while the elderly man has been held at lower grade occupations. The fourth is that labor demand for highly educated workers has exceeded the increased labor supply of the group, while the demand for low educated workers has decreased far beyond the declined labor supply. As a result, college premium has increased from 139% in 1993 to 157.8% in 2005. The final main implication of this study is that the industrialization theory and modernization hypothesis still holds for the LFPR of Korean older males. However, the elderly affluence hypothesis of the LFPR of older males are hardly persuasive in explaining Korean phenomenon. Especially, we find that the elderly poverty is the main mechanism in determining the Korean LFPR in old ages. This supports the elderly poverty labor hypothesis presented in this study. Skill-biased technological change hypothesis partially explains the LFPR of older man. However, we believe that other factors; human capital specially high school education rather than university education and skill required in less skill biased occupations or the poverty; also have taken effect.

• KDI Journal of Economic Policy
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• v.34 no.2
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• pp.55-93
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• 2012

In Korea, energy policies are actualized through various energy-related plans. Recently, however, as high-ranking plans, which are very vision-oriented, continually set higher sector-by-sector goals, subordinate action plans, which require consistency, encounter distortions in their establishment process. Also, each subordinate action plan reveals limitations in terms of securing flexibility of the plan in responding to uncertainties of the future. These problems pose potential risks such as causing huge social costs. In this regard, with an aim to provide empirical evidence for discussions on improving the procedure for developing and executing Korea's energy plans, this study mainly analyzes the Basic Plan on Electricity Demand and Supply-one of the most important subordinate action plans-in order to explain the problems of the Basic Plan in a logical manner, and potential problems that could occur in the process of sustaining consistency between the Basic Plan and its higher-ranking plans. Further, this paper estimates the scale of social costs caused by those problems assuming realistic conditions. According to the result, in the case of where maximum electric power is estimated to be 7% (15%) less than the actual amount in the Basic Plan on Electricity Demand and Supply, the annual generation cost will rise by 286 billion won and (1.2 trillion won) in 2020. Such social costs are found to occur even when establishing and executing the Basic plan according to the target goal set by its higher-ranking plan, the National Energy Master Plan. In addition, when another higher-ranking GHG reduction master plan requires the electricity sector to reduce emissions by additional 5% in the GHG emissions from the right mix in electricity generation with 'zero' cost of carbon emission, the annual generation cost will rise by approximately 915 billion won in 2020. On the other hand, the analysis finds that since economic feasibility of electric powers in Korea varies significantly depending on their type, Korea is expected to face very small potential social costs caused by uncertainties over the future price of carbon dioxide in the process of establishing the Basic Plan.

• KDI Journal of Economic Policy
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• v.31 no.1
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• pp.169-206
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• 2009

This study stems from a question, "How should we understand the pattern of the Korean economy after the 1990s?" Among various analytic methods applicable, this study chooses a Structural Vector Autoregression (SVAR) with long-run restrictions, identifies diverse impacts that gave rise to the current status of the Korean economy, and differentiates relative contributions of those impacts. To that end, SVAR is applied to four economic models; Blanchard and Quah (1989)'s 2-variable model, its 3-variable extensions, and the two other New Keynesian type linear models modified from Stock and Watson (2002). Especially, the latter two models are devised to reflect the recent transitions in the determination of foreign exchange rate (from a fixed rate regime to a flexible rate one) as well as the monetary policy rule (from aggregate targeting to inflation targeting). When organizing the assumed results in the form of impulse response and forecasting error variance decomposition, two common denominators are found as follows. First, changes in the rate of economic growth are mainly attributable to the impact on productivity, and such trend has grown strong since the 2000s, which indicates that Korea's economic growth since the 2000s has been closely associated with its potential growth rate. Second, the magnitude or consistency of impact responses tends to have subsided since the 2000s. Given Korea's high dependence on trade, it is possible that low interest rates, low inflation, steady growth, and the economic emergence of China as a world player have helped secure capital and demand for export and import, which therefore might reduced the impact of each sector on overall economic status. Despite the fact that a diverse mixture of models and impacts has been used for analysis, always two common findings are observed in the result. Therefore, it can be concluded that the decreased rate of economic growth of Korea since 2000 appears to be on the same track as the decrease in Korea's potential growth rate. The contents of this paper are constructed as follows: The second section observes the recent trend of the economic development of Korea and related Korean articles, which might help in clearly defining the scope and analytic methodology of this study. The third section provides an analysis model to be used in this study, which is Structural VAR as mentioned above. Variables used, estimation equations, and identification conditions of impacts are explained. The fourth section reports estimation results derived by the previously introduced model, and the fifth section concludes.

• Management & Information Systems Review
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• v.37 no.3
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• pp.83-113
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• 2018

The purpose of this study to empirically examine a smart work investment and job performance by change resistance. Firstly, There investigates mediating role of the communication between the smart work investment and the job performance. Secondly, It will identify the job productivity differences through a level of organizational change resistance that reduced smart work investment. The smart work is to provide the flexibility of time and location and is a working method to improve a work productivity of organization members. The introduction of smart work means the adoption of new organizational culture, institution and technology and requires a novel change of a custom and pattern on existing organization culture and institution because of transformation form of communication and collaboration. The method of this study adopts a structural equation model to test a mediating effect of communication and a moderating effect of change resistance level. This model confirms whether smart work investments provide a positive impact on communication and organizational productivity. In addition, I will classify a change resistance level of smart work by cluster analysis and then check a critical path difference of job productivity between each group. As a result, The organizational IT, institution and culture on the smart work investment appeared to important influencers in communication and also had a direct influence of individual performance. Also, The three independent variables of smart work investment have an indirect influence of individual and organizational performance through communication mediating variables. However, the organizational IT and institution as independent variables do not provide direct influence of organization performance. Nevertheless, two independent variables of organizational IT and institution have an indirect influence the organization performance through communication mediating variables. As a result of confirming a productivity of three groups on organization resistance, there was a difference the individual and organizational performance among groups. The low-level group of organizational resistance showed high coefficient value of performance compared to other groups. The group analysis implications, The smart work investment appeared significantly to revise the institution first, build culture secondly and advanced technology lastly. The theoretical implication from this study contributes an extension of social science theory through socio-technical systems, institution, culture, change resistance and job performance based on smart work. The practical implications explain the smart work success in step-by-step investment rather than radical investment as level management of change resistance. In future research, the smart work performance between private and public firms will analyze a difference of the organizational culture, institution, technology and performance.

• Journal of Aquaculture
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• v.14 no.3
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• pp.181-195
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• 2001

To stabilize the lantern cage culture system of Patinopecten yessoensis(Jay) in the eastern coast of Korean peninsula, optimum conditions such as time of transplantation, rearing density and depth, and time of harvest were identified. During the period from January 1991 to December 1998, the water temperature ranged from 4.7 to 21.4$^{\circ}C$ at 15-30 m depth and 4.9 to 25.7$^{\circ}C$ at the surface; these thermal ranges were within the optimal ranges (5-23$^{\circ}C$) prevailing at 15-30 m depth at surface water. Annual thermal changes indicated that the prevailing temperature during the years 1993 and 1996 was near optimum, but higher during the years 1994, 1997 and 1998, when mass mortality and growth retardation occurred. Salinity (32.0- 34.4$\textperthousand$) and dissolved oxygen (4.14 -8.11 $\mu\textrm{g}$/l) at 15 m depth were well within the optimum ranges. The chlorophyll concentrations (0.06 - 2.73$\mu\textrm{g}$/l) indicated that the study area was oligotrophic, although mass mortality did occur, when chlorophyll concentrations were high, especially in summer. Hence water temperatures and chlorophyll concentration are major factors related to survival and growth of the scallop. In terms of the shell height maximum growth occurred during spring (March-May; 8 - l3$^{\circ}C$) and fall (October-December; 11-l7$^{\circ}C$) in the lantern cage culture. Slow growth was recorded during late winter January-february; less than 7$^{\circ}C$) and mid-summer (August- September; more than 18$^{\circ}C$). Daily growth of shell height and total weight were 0.02∼0.24 mm and -0.07∼0.90 g at the rearing density of 12 individuals per net. Optimal .earing density in the lantern cage (ø50${\times}$20 cm) was 10∼15 individuals with the shell height of 5∼6 cm. The fastest growth rates were observed at 15∼20 m depth; however, it is recommended that 20∼30 m would be optimal. The scallops require 22 months to attain the commercial size of 10 cm shell height and 140 g total weigh, and are best harvested and sold during March-April.

• Korean journal of applied entomology
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• v.9 no.1
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• pp.25-32
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• 1970

This experiment was conducted to find out the simultaneous control effect of granulated insecticides on the several major rice insect pests in Korea. The granulated insecticides used were Terracur P$5\%$ (one of the phosphoric insecticides), Lebaycid $5\%$, and Sang-gamma (gamma-BHC) $6\%$. Those insecticides were broadcasted by hand on the paddy field at the ratio of 3kg. in June and 4kg. in August per 10 a, and the date of insecticidal application was based on the maximum moth occurrence of the rice stem borer in 1969. The rice insect pests tested in this study were rice stem borer (Chilo suppressalis W.), green rice leafhopper (Nephotettix bipunctatus cincticeps U.), smiller brown planthopper (Laodelphax striatellus F.), and white back planthopper (Sogotella furcifera H.). For the study of residual effectiveness of the insecticides, the rice stem borer larvae just hatched from the eggs were installed on the sheath of rice plants collected from the paddy field after insecticidal treatment, and the mortality was made at 48 hours after installation. High mortality was observed in Terracur P and Sang-gamma treatments and low mortality in Lebaycid treatment. The duration of residual effects giving about 50% mortality was about 14 days in Sang-gamma and about 6 days in Terracur P treatments. The study on the effectiveness of the insecticides to the rice stem borer in the paddy field was made by the number of dead blades and white heads of the rice plants injured by the larvae, and the number of survival larvae in the straws after crop harvest. The order of insecticidal effectiveness to the rice stem borer was Terracur P=Sang-gamm>Lebaycid. The study on the effectiveness of the insecticides to the leafhoppers and planthoppers in the paddy field was made by the population density by sweeping (5 times) at the given day intervals after treatments. Terracur P was highly effective for the control of the green rice leafhoppers and Lebaycid was moderately effective, but Sang-gamma seemed not to be effective. The effectiveness of the insecticides tested to the planthoppers was not clear, and it seemed to related with the low insect population density. Study on the determination of proper timing of insecticidal application was not also made clear, and it seemed to be short in the range of day intervals in the insecticidal application. For the study on the control effects of the rice insect pests, rice yield per 100 hills per plot was observed. There was no statistically significant difference among the treatments in rice yields, but the order of yield (Terracur P>Sang-gamma>Lebaycid>Control) was paralleled with the tends of control effects above mentioned. In a view point of simultaneous control of the rice stem borers and green rice leafhoppers by the application of granulated insecticides, Terracur P and Lebaycid were more effective than Sang-gamma which have been used.

• Food Science and Preservation
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• v.12 no.1
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• pp.36-42
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• 2005

The purpose of this study was to investigate the component and quality characteristics of green tea. Four kinds of green tea powder obtained from Hwagae area were evaluated the component of carbohydrates, protein crude fat and crude ash. Also the content of ascorbic acid, minerals and polyphenols in green tea powder were evaluated. Quality characteristics of green tea powder was evaluated by Hunter's colur value and sensory evaluation. Green tea was composed of $9.2\~11.8\%$ of moisture, $4.9\~6.1\%$ of crude ash, $5.2\~6.1\%$ of crude fat, $22.5\~26.4\%$ of protein and $50.4\~55.1\%$ of cabohydrates. The content of total ascorbic acid in green tea powder was $312\~392mg/100g$ and dehydiuascorbic acid was $157\~176mg/100g$. The contents of minerals in green tea powder sodium was $340\~580mg/100g$, magnesium was $242\~320mg/100g$, potassium $223\~278mg/100g$ me calcium $145.7\~238.7mg/100g$. Polyphenol content of green tea powder was $7.8\~9.3\%$ which was the highest in A and the lowest in B. Hunters color values of green tea, lightness(L) was $52.3\~69.6$, redness(a) was $0.11\~-5.61$, yellowness(b) was $14.23\~23.34$, which were better in green tea C and D than green tea A and B. From sensory evaluation of green tea powders, green tea D obtained the significant highest scores in color, flavor and overall quality(p<0.05) and followed by green tea C, Green tea powder C and D which have high levels of protein and ascorbic acid were evaluated as good quality in color and sensory evaluation.

• Food Science and Preservation
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• v.23 no.6
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• pp.778-787
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• 2016

Fermented vinegars using pear was compared according to the appled side materials. Quality characteristics of three kinds of the fermented vinegars (pear vinegar, PV; pear black rice vinegar, PBV; pear mint vinegar, PMV) were investigated, which includes pH, total acidity, colors, the contents of sugar, amino acids, total polyphenol, and total flavonoid, ${\alpha}^{\prime}{\alpha}-diphenyl-{\beta}-pycrylhydrazyl$ (DPPH) radical scavenging ability, and sensory evaluation. Brown rice vinegar (BRV) was used as a control. The pH and total acidity of the fermented pear vinegars were significantly different showing the range of 3.17~3.43 and 4.01~5.05%, respectively (p<0.05). The sugar contents of PV and PMV were significantly higher than other vinegars (p<0.05). L, a, and b values were the highest in PV, PBV, and PMV, respectively. Among the four vinegars, the essential amino acids were the highest in PV with the order of lysine, isoleucine, valine, and threonine. Besides, the fermented pear vinegars have many non-essential amino acids such as glutamic acid and aspartic acid. The aspartic acid content was the highest in PV while glutamic acid content was the highest in BRV. The total polyphenol content was the highest in PV while total flavonoid content was the highest in PBV. The DPPH radical scavenging ability (%) was the highest in PV. In sensory evaluation, PBV showed the highest color, taste and overall preference scores. These results show that pear would be desirable to prepare high-quality vinegars and functional foods.

• Food Science and Preservation
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• v.24 no.2
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• pp.289-293
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• 2017

Ethanol extract of garlic peels (GPE) was investigated for its antiproliferative effects on human cancer cell lines. Human lung cancer cell line A549 treated with $500{\mu}g/mL$ GPE resulted in the growth inhibition of A549 by 90%. In stomach cancer cell AGS proliferation inhibition activity, GPE showed 45% and 71% inhibition of AGS growth at $1,000{\mu}g/mL$ and $2,000{\mu}g/mL$, respectively. GPE inhibited the growth of the breast cancer cells MCF-7 effectively at low concentration and showed 78% and 90% inhibitions of MCF-7 growth at $200{\mu}g/mL$ and $500{\mu}g/mL$, respectively. GPE showed very significant antiproliferation effect on liver cancer cell line Hep3B and inhibited Hep3B cell growth by 57% at $100{\mu}g/mL$, and the inhibition's rate increased up to 87% at $500{\mu}g/mL$. Antiproliferation effect of GPE on colorectal cancer cell HT-29 showed 15% reduction of HT-29 cell growth at $200{\mu}g/mL$ and the growth rate was reduced in a dose dependent manner up to $1,000{\mu}g/mL$. These results indicated that GPE had high antiproliferation effects on breast and liver cancer cell lines at low concentrations ($200{\mu}g/mL$), and by higher concentrations over $500{\mu}g/mL$, GPE inhibited the growth of A549 and HT-29. The results of our study suggested the potential use of garlic peels for use as an excellent antiproliferative substance for human cancer cells.

• Journal of dental hygiene science
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• v.7 no.3
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• pp.129-133
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• 2007

This study was carried out to see the effect of dental auxiliary product groups being used in case of not being able to brush teeth. This study was executed for 70 students in the Dept. of Dental Hygiene of S Health College, and it was divided into the group which used brushing teeth, the one which used only dental auxiliary products, the one which did onion juice gargle, etc, and measured the effect on the reduction of oral malodor. The experimental results of the study were as below. 1) After onion juice gargle, in the experimental group A which brushed teeth, it showed lasting decrease of oral malodor until 20min since the experiment, and after 30min, the degree of oral malodor started to increase again. 2) After onion juice gargle, the result of the experimental group B which took only supplementary products such as garglin, chewing gum, intaking green tea with roasted rice & brushing a tongue and so on, was as follows. First, in case of experimental group BG which used garglin, until 30 min has passed since the experiment, it showed the lasting reduction of oral malodor as the same trend with the experimental group BG. Second, in chewing gum (experimental group BC), intaking green tea with roasted rice (experimental group BT), and brushing a tongue (experimental group BO), continuous reduction of oral malodor was shown until 10minutes has passed since the experiment, but, after 20minutes, we could see the degree of oral malodor started to increase again. 3) After onion juice gargle, in the experimental group C which only the degree of oral malodor was measured with the passage of time, neither brushing teeth nor using auxiliary goods, until 30min since the experiment, it showed the similar trend of the reduction of oral malodor with other experimental groups, but, it showed high degree of oral malodor, as compared with other experimental groups A and B.