• Journal of the Korean Society of Groundwater Environment
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• v.5 no.1
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• pp.44-55
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• 1998

Imgok creek is the most severly polluted one out of the streams which have been being polluted by acid drainages from the abandoned coal mines in the Gangdong-Myeon area, the central part of the so called Gangreung coal field. Imgok creek is being mainly polluted by the drainage from Youngdong coal mine, which supplies such pollutants as Mg, Fe, Al, Si, Ca, Mn, and SO$_4$as major dissolved components and Cr, Co, Ni, Cu, Zn, Rb, Sr, Cd, Pb, and U as minor dissolved components. After the influx, the pollutants migrate mainly as dissolved solid, rather than as suspended solids along Imgok creek. The suspended solids in Imgok creek are very rich in Fe and Al, indicating that they mainly consist of the precipitates of present and past from the polluted water. Most of the dissolved components in the stream waters of Imgok creek removed from the aqueous phase by precipitation and dilution before reaching the East Sea, so that water quality of the downstreams of Imgok creek is very similar to that of unpolluted tributaries. It suggests that Imgok creek itself is now being severly polluted by the acid drainages from the abandoned coal mines, but the East Sea is relatively safe from the same pollution. The estuary and sea waters around the Goonseon estuary, which accepts Imgok creek water, certainly show no significant difference in chemical compositions from the mean oceanic water. The bottom sediments at the sampling sites of the sea waters also show no significant trend of their component variation, especially the variations of Fe, SO$_4$ and Al concentrations. These facts again supper that the acid mine drainage is not considerablly polluting the East Sea. However, the tributaries supplying the fresh water to the Imgok creek will be certainly polluted by the acid mine drainage as time passes and pollutants will have more chance to migrate in significant amount to the downstream area, which all can be a real threats to the East Sea on the pollution possibility. Therefore, it is suggested that urgently required are not only water quality and environmental improvement of the severely polluted Imgok creek but also preparation of the measures on the possible future pollution of the East Sea by the acid drainage from the abandoned coal mines in the area, while the East Sea is still not much affected by the pollution of the same kind.

• The Korean Journal of Pharmacology
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• v.21 no.1
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• pp.49-61
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• 1985

In view of the facts that dopamine (DA) when given directly into a lateral ventricle (i.c.v.) of the rabbit brain induces antidiuresis and that haloperidol, a non-specific antagonist of DA receptors, produces anti-diuresis in smaller doses and diuresis and natriuresis in larger doses, the present study was undertaken to delineate the roles of various DA receptors involved in the center-mediated regulation of renal function. Bromocriptine (BRC), a relatively specific agonist of D-2 receptors and at the same time a D-,1 antagonist, elicited natriuresis and diuresis when given i.c.v. in doses ranging from 20 to 600 {\mu}g/kg$, roughly in dose-related fashion, while the renal perfusion and glomerular filtration progressively decreased with doses, indicating that the diuretic, natriuretic action resides in the tubules, not related to the hemodynamic effects. These diuresis and natriuresis were most marked with 200 ${\mu}g/kg$, with the fractional sodium excretion reaching about 10%. With 600 ${\mu}g/kg$, however, the diuretic, natriuretic action was preceded by a transient oliguria resulting from severe reduction of renal perfusion, concomitant with marked but transient hypertension. When given intravenously, however, BRC produced antidiuresis and antinatriuresis along with decreases in renal hemodynamics associated with systemic hypotension, thus indicating that the renal effects produced by i.c.v. BRC is not caused by a direct renal effects of the agent which might have reached the systemic circulation. In experiments in which DA was given i.c.v. prior to BRC, 150 ${\mu}g/kg$ DA did not affect the effects of BRC (200 ${\mu}g/kg$), while 500 ${\mu}g/kg$ DA abolished the BRC effect. In rabbits treated with reserpine, 1 mg/kg i.v.,24 h prior to the experiment, i.c.v. BRC could unfold its renal effects not only undiminished but rather exaggerated and more promptly. In preparations in which one kidney is deprived of nervous connection, the denervated kidney responded with marked diuresis and natriuresis, whereas the innervated, control kidney exhibited antidiuresis. These observations suggest that i.c.v. BRC influences the renal function through release of some humoral natriuretic factor as well as by increasing sympathetic tone, and that various DA receptors might be involved with differential roles in the center-mediated regulation of the renal function.

• Journal of Navigation and Port Research
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• v.28 no.10 s.96
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• pp.899-908
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• 2004

The rise of income and introduction of 5 day a week working system give korean people opportunities to enjoy their leisure time. And many korean people have much interest in oceanic sports such as yachting and also oceanic leisure equipments. With the popularization and development of the equipments, the scope of oceanic activities has been expanding in Korea just as in the advanced oceanic countries. However, The current conditions for the sports in Korea are not advanced and even worse than underdeveloped countries. In order to develop the underdeveloped resources of Korean marina, we need to customize the marina models of advanced nations to serve the specific needs and circumstances of Korea As such we have carried out a comparative analysis of how Austrailia, Newzealand, Singapore, japan and Malaysia operate their marina, reaching the following conclusions. Firstly, in marina operations, in order to protect personal property rights and to preserve the environment, we must operate membership and non-membership, profit and non-profit schemes separately, yet without regulating the dress code entering or leaving the club house. Secondly, in order to accumulate greater value added, new sporting events should be hosted each year. There is also the need for an active use of volunteers, the generation of greater interest in yacht tourism, and the simplification of CIQ procedures for foreign yachts as well as the provision of language services. Thirdly, a permanent yacht school should be established, and classes should be taught by qualified instructors. Beginners, intermediary, and advanced learner classes should be managed separately with special emphasis on the dinghy yacht program for children. Fourthly, arrival and departure at the moorings must be regulated autonomically, and there must be systematic measures for the marina to be able, in part, to compensate for loss and damages to equipment, security and surveillance after usage fees have been paid for. Fifthly, marine safety personnel must be formed in accordance with Korea's current circumstances from civilian organizations in order to be used actively in benchmarking, rescue operations, and oceanic searches at times of disaster at sea.

• Korean Journal of Microbiology
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• v.51 no.4
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• pp.355-363
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• 2015

The present work quantified the growth of young biofilm in a model distribution system that was fed with chlorinated drinking water at a hydraulic retention time of 2 h. Bacterial biofilms grew on the surface of polyvinyl chloride (PVC) slides at a specific growth rate of $0.14{\pm}0.09day^{-1}$ for total bacteria and $0.16{\pm}0.08day^{-1}$ for heterotrophic bacteria, reaching $3.1{\times}10^4cells/cm^2$ and $6.6{\times}10^3CFU/cm^2$ after 10 days, respectively. The specific growth rates of biofilm-forming bacteria were found to be much higher than those of bulk-phase bacteria, suggesting that biofilm bacteria account for a major part of the bacterial production in this model system. Biofilm isolates exhibited characteristic kinetic properties, as determined by ${\mu}_{max}$ and $K_S$ values using the Monod model, in a defined growth medium containing various amounts of acetate. The lowest ${\mu}_{max}$ value was observed in bacterial species belonging to the genus Methylobacterium, and their slow growth seemed to confer high resistance to chlorine treatment (0.5 mg/L for 10 min). $K_S$ values (inversely related to substrate affinity) of Sphingomonas were two orders of magnitude lower for acetate carbon than those of other isolates. The Sphingomonas isolates may have obligate-oligotrophic characteristics, since the lower $K_S$ values allow them to thrive under nutrient-deficient conditions. These results provide a better understanding and control of multi-species bacterial biofilms that develop within days in a drinking water distribution system.

• Journal of Korean Home Economics Education Association
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• v.29 no.2
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• pp.1-22
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• 2017

The purpose of this research is to share the experience of reflective practice of a Home Economics teacher professional learning community(PLC) operator and to share better suggestions through reflection on PLC operation. All conversation in the 18 sessions of the PLC totally from May 31st 2013 to May 19th 2014 was recorded and transcribed. All materials of PLC activity were qualitatively analysed. Its themes were grounded on its coding and categorization scheme. Findings and conclusions of this study are as followings. The experience of learning the PLC for a year has found that it is the power to keep the PLC alive: courage and anxiety to face anxiety and anxiety about new challenges, the importance of theme selection, a teacher with a reckless challenge, shares of becoming a leader. Through reflection, I learned that concerns require attention to other teachers and the need for a 'New Round' for ongoing meetings. I, as a operator, did not fully consider participant's different interest as well as a program for a new round due to the lack of management experience. It led to the low participations in latter sessions of PLC. Suggestions are put as solutions to improve these problems; (1) grouping participants by school levels when collecting participants, (2) setting operation period and program applying participants' opinions, and (3) operating short-term PLC with certain themes to immerse reaching goal and satisfaction in short time.

• KDI Journal of Economic Policy
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• v.30 no.1
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• pp.71-130
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• 2008

Using data from the Korean Labor & Income Panel Study (KLIPS), this study investigates private income transfers in Korea, where adult children have undertaken the most responsibility of supporting their elderly parents without well-established social safety net for the elderly. According to the KLIPS data, three out of five households provided some type of support for their aged parents and two out of five households of the elderly received financial support from their adult children on a regular base. However, the private income transfers in Korea are not enough to alleviate the impact of the fall in the earned income of those who retired and are approaching an age of needing financial assistance from external source. The monthly income of those at least the age of 75, even with the earning of their spouses, is below the staggering amount of 450,000 won, which indicates that the elderly in Korea are at high risk of poverty. In order to analyze microeconomic factors affecting the private income transfers to the elderly parents, the following three samples extracted from the KLIPS data are used: a sample of respondents of age 50 or older with detailed information on their financial status; a five-year household panel sample in which their unobserved family-specific and time-invariant characteristics can be controlled by the fixed-effects model; and a sample of the younger split-off household in which characteristics of both the elderly household and their adult children household can be controlled simultaneously. The results of estimating private income transfer models using these samples can be summarized as follows. First, the dominant motive lies on the children-to-parent altruistic relationship. Additionally, another is based on exchange motive, which is paid to the elderly parents who take care of their grandchildren. Second, the amount of private income transfers has negative correlation with the income of the elderly parents, while being positively correlated with the income of the adult children. However, its income elasticity is not that high. Third, the amount of private income transfers shows a pattern of reaching the highest level when the elderly parents are in the age of 75 years old, following a decreasing pattern thereafter. Fourth, public assistance, such as the National Basic Livelihood Security benefit, appears to crowd out private transfers. Private transfers have fared better than public transfers in alleviating elderly poverty, but the role of public transfers has been increasing rapidly since the welfare expansion after the financial crisis in the late 1990s, so that one of four elderly people depends on public transfers as their main income source in 2003. As of the same year, however, there existed and occupied 12% of the elderly households those who seemed eligible for the National Basic Livelihood benefit but did not receive any public assistance. To remove elderly poverty, government may need to improve welfare delivery system as well as to increase welfare budget for the poor. In the face of persistent elderly poverty and increasing demand for public support for the elderly, which will lead to increasing government debt, welfare policy needs targeting toward the neediest rather than expanding universal benefits that have less effect of income redistribution and heavier cost. Identifying every disadvantaged elderly in dire need for economic support and providing them with the basic livelihood security would be the most important and imminent responsibility that we all should assume to prepare for the growing aged population, and this also should accompany measures to utilize the elderly workforce with enough capability and strong will to work.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1619-1625
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• 2012

The purpose of this study is to determine long-term storage conditions for winter kimchi. Kimchi was stored in a kimchi refrigerator for 6 months with or without fermentation. Four different temperature systems used were as follows: 5 days at $10^{\circ}C$ followed by storage at $-2.5^{\circ}C$ (F1), 1 day at $15^{\circ}C$ followed by storage at $-2.5^{\circ}C$ (F2), storage at $-1^{\circ}C$ (S1), or at $-2.5^{\circ}C$ (S2). Time periods required for F1, F2, S1, or S2 kimchi to reach pH 4.4 and acidity 0.6% were 2, 8, 12, and 22 weeks, respectively. Lactobacillus spp. growth on F1 and F2 kimchi was faster and greater than that on S1 and S2 kimchi, revealing a maximum concentration of 8~9 verses 6.8 log CFU/mL, respectively. However, Leuconostoc spp. were fully grown (8~9 log CFU/mL) on all four kimchi samples regardless of temperature, even at $-2.5^{\circ}C$, although the times required to reach maximum growth were different. Growth of Lactobacillus and Leuconostoc spp. both decreased after reaching maximum levels, except for F1 kimchi. Sensory evaluation results for 3 month storage showed that F1 kimchi was the best among kimchi samples in terms of appearance, acidic taste, carbonated taste, crispiness, and moldy smell. For 6 months of storage, F1 and S1 kimchi were the most highly evaluated among the kimchi samples. Sensory evaluation result for S1 kimchi stored at $-1^{\circ}C$ was comparable to that of F1 kimchi due to fully grown Leuconostoc spp. Acidities of F1 and S1 kimchi after 6 months of storage were 0.8 and 0.7%, respectively. Taken together, fermentation of kimchi at $10^{\circ}C$ for 5 days followed by storage at $-2.5^{\circ}C$ for 6 months was optimal for high quality kimchi. Sensory properties of winter kimchi were significantly influenced by the degree of fermentation.

• The Korean Journal of Financial Management
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• v.10 no.1
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• pp.249-280
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• 1993

Recent financial theory views insurance policies as financial instruments that are traded in markets and whose prices reflect the forces of supply and demand. This article analyzes individual's insurance purchasing behavior along with capital market investment activities, which will provide a more realistic look at the tradeoff between insurance and investment in the individual's budget constraint. It is shown that the financial economic concept of insurance cost should reflect the opportunity cost of insurance premium. The author demonstrates the importance of riskless and risky financial assets in reaching an equilibrium insurance premium. In addition, the paper also investigates how the investment income could affect the four established theorems on traditional insurance literature. At the present time in Korea, the price deregulation is being debated as the most important current issue in insurance industry. In view of the results of this paper, insurance companies should recognize investment income in pricing their coverage if insurance prices are deregulated. Otherwise. price competition may force insurance companies to restrict coverage or to leave the market.

• Journal of agricultural medicine and community health
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• v.27 no.1
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• pp.155-164
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• 2002

Hypertension is the most frequent disease of chronic circulatory diseases and major intermediate cause or risk of the cerebrovascular disease which is a leading cause of death in Korea. Therefore, management of hypertension is an important issue in Korean healthcare. Especially, therapeutic compliance of hypertensives is very important because the hypertensive patients should receive anti-hypertensive treatment as long as the condition exists. However, many patients drop out of treatment, which is a major problem that needs to be solved through a hypertension control program. This study was carried out to provide basic data and counter measule for the hypertension control program in the community which aimed to keep the patients receiving treatment continuously. In order to investigate compliance of hypertensive patients during three months follow-up and the rate of control of hypertension, the data were collected during February, 2001, by reviewing medical records of 295 hypertensive patients who had been registered to Gunnam-myeon health subcenter before November, 2000. The author also study the dropout reasons by interviewing 58 patients among 68 dropout patients. The results were as follows: 1. Among the 295 subjects, 108(36.6%) were male and 187(63.4%) were female. Statistically, female hypertensives had a higher mean age than male(64.6 vs 66.3, p<0.05). 2. The 54.9% of the patients took anti-hypertensive medicine continuously for the past three months. And 19.3% had drug intermittently, and 25.8% dropped out of treatment. 3. Among several variables, such as sex, age, health insurance, the time taken from a patient's village to the health subcenter, only the last one was found to be significantly related to therapeutic compliance in the contingency table analysis. 4. The dropout reasons by multiple response were as follows, 'no symptom or no problem' (23.9%), 'change to other hospitals'(19.4%), 'geographical barrier'(17.9%), 'change to a neighborhood drugstore' (14.9%), 'immobility'(7.5%), 'economic barrier'(6.0%), 'unsatisfactory services of the health subcenter'(4.4%). 5. The mean blood pressure of 295 subjects was $144.9{\pm}12.9/86.88{\pm}8.6mmHg$. 6. The 32.5% of the subjects were controlled below 140/90mmHg. Conclusions: In order to improve the low rates of treatment and control of hypertension in rural hypertensives, a more active and systematic hypertension control program, including out-reaching follow-up management, is required in rural area. Especially, for health education of hypertensive patients, emphasis should placed on correcting wrong attitude toward hypertension.

• Journal of Radiation Protection and Research
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• v.25 no.4
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• pp.207-216
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• 2000

Continuous measurements of radon progeny concentrations in the open atmosphere and measurements of meteorological parameters were performed in Tajeon, using a continuous gross alpha/beta aerosol monitor and a weather measuring equipment between July 1999 and July 2000. These data were analyzed for half-hourly, daily, and seasonal variations. The distribution of daily averaged equilibrium equivalent radon concentration$(EEC_{Rn})$ had an arithmetic mean value of $11.3{\pm}5.86Bqm^{-3}$ with the coefficient of variation of about 50% and the geometric mean was $10.3Bqm^{-3}$. The $EEC_{Rn}$ varies between 0.83 and $43.3Bqm^{-3}$, depending on time of day and weather conditions. Half-hourly averaged data indicated a diurnal pattern with the outdoor $EEC_{Rn}$ reaching a maximum at sunrise and a minimum at sunset. The pattern of the seasonal variation of the $EEC_{Rn}$ in Taejon had a tendency of minimum concentration occurring in the summer(July) and maximum concentration occurring in the late autumn(November). But the seasonal variation of the $EEC_{Rn}$ is expect to vary greatly from place to place. The outdoor $EEC_{Rn}$ was highly dependent on the local climate features. Particularly the $EEC_{Rn}$an rapidly drops less than $5Bqm^{-3}$ in case of blowing heavily higher than wind speed of $6msec^{-1}$, reversely the days with more than $30Bqm^{-3}$ were at a calm weather condition with the wind speed of lower than $1msec^{-1}$.