• Animal cells and systems
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• v.13 no.1
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• pp.83-89
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• 2009

Investigations were made on population biology of Pampus echinogaster (Basilewsky, 1855) in the coastal areas of Korea, Yellow Sea, between August 2005 and July 2006. Population structure was not significantly different between male and females. Monthly variation of gonadosomatic index (GSI) of both sexes defined spawning period extending from March through July. A similar pattern was also observed in change at maturity stages. For males and females GSI was positively correlated with hepatosomatic index (HSI). Fecundity, ranging from 41,250 to 103,610 eggs, was related to body size, indicating that body size is the useful determinant of fecundity. The sexual maturity ($L_{50}$) was estimated as 14.98 cm TL for males and 19.32 cm TL for females. Parameters of growth estimated by the modified von Bertalanffy growth function model showed that the values of $L_{\infty}$ and K for combined data were 39.12 cm TL and 0.65 $yr^{-1}$. The growth performance index of this study (2.75) was higher than that of the previous study (2.45). This difference could be attributed to sampling method. The recruitment patterns indicated one normally distributed group. Percentage of the recruitment was 51.04% in the spawning season and the highest in August (19.78%).

• KDI Journal of Economic Policy
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• v.26 no.1
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• pp.105-140
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• 2004

Korea is entering the class of aging population nations. This paper investigates the extent demographic factors and the aging population affect the saving rate, using an extended life-cycle/permanent-income hypothesis on saving. The results of the tests with Korean household survey data from 1977 to 2002 reveal that real saving rates increase when the duration of lifetime and per household real disposable income rise, and decrease when the growth rate of income and net worth-to-GDP ratio rises. The growth rate of per household real disposable income has negative effects, suggesting that households calculate their life cycle income in a forward looking manner. The elasticities with respect to a change in the lifetime horizon and the growth rate of per household income are 0.58 and -0.03, respectively. A one percent rise in the net worth to GDP ratio reduces the saving rate by 0.3 percent. A one percent rise in per household income increases it by 0.33 percent. The younger-age and the elder-age dependency ratios have insignificant effects on the household saving rate behavior. When Korean life expectancy rises, the private saving rate declines modestly and the government saving rate declines substantially. The economy's real net saving rate declines from 33 percent in 2002 to 30 percent by the year 2030.

• Journal of Korean Clinical Nursing Research
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• v.14 no.1
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• pp.25-32
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• 2008

Purpose: The purpose of this study was to examine quality of life with patients in 12 months after coronary artery bypass graft surgery, compared with general population. Method: A cross-sectional comparative study was designed. Study participants were 90 adults who had undergone CABG surgery (n=45) in experimental group and general population (n=45) in control group. The subjects were asked the questionnaire (SF-36, Short Form-36) regarding the quality of life. The data were analyzed by the SPSS 13.0 program including frequency, percentage, $x^2$ test, t-test and One-Way ANOVA. Results: There were no significant differences in the quality of life between two groups including physical functioning (t=-.938, p=.351), role-physical limitation (t=-.322, p=.748), bodily pain (t=-.938, p=.351), general health (t=-.1418, p=.888), vitality (t=-.816, p=.417), social functioning (t=.720, p=.474), role-emotional limitation (t=-.710, p=.479), mental health (t=-.431, p=.667). Conclusion: Even though patients in experimental group had operation experience, the quality of life examined on the time of 1 year after bypass surgery is similar in that of general population. We suggest the study change the design as examination of quality of life before and after coronary artery bypass graft surgery.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.182-182
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• 2017

Many small island nations rely on groundwater as their only other source of freshwater in addition to rainwater harvesting. The volume of groundwater resource of small island nations are further limited by their smaller surface area and specific hydrogeology. The rapid growth of population and tourism has led to increasing water demands and pollution of available groundwater resources. The predicted climate change effects pose significant threats to the already vulnerable freshwater lens of small islands in the form of rise in sea level, coastal inundation, saltwater intrusion, varied pattern of precipitation leading to droughts and storm surges. The effects of climate change are further aggravated by manmade stresses like increased pumping. Thus small island water resources are highly threatened under the effects of climate change. But due to the limited technical and financial capacity most of the small island developing states were unable to conduct detailed technical investigations on the effects of climate change on their water resources. In this study, we investigate how well small island countries are preparing for climate change. The current state of freshwater resources, impacts of predicted climate change along with adaptation and management strategies planned and implemented by small island countries are reviewed. Proper assessment and management practices can aid in sustaining the groundwater resources of small islands under climate change.

• Korean Journal of Environmental Biology
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• v.36 no.1
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• pp.1-10
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• 2018

The objective of this study was to identify the effects of farming practices on the Misgurnus anguillicaudatus population, including their habitat characteristics, length frequency and the length-weight relationships of M. anguillicaudatus population; this study investigated the differences of the population living in environment-friendly (EFP) and conventional paddy fields (CP). As the result of age distribution by length frequency of M. anguillicaudatus, the EFP showed various age distributions which were not present in the CP. In particular, the age $0^+$ (28-51 mm) of individuals in the CP were significantly lower than those in the EFP. In May, the number of individuals was similar in CP and EFP, which led to the assumption that the M. anguillicaudatus population living in a shallow depth was killed by rotary and tillage works. The regression coefficient (b) in relation to the length-weight of M. anguillicaudatus population was 3.0, which appeared relatively stable as a habitat condition in the CP and EFP, except in June. The condition factor for M. anguillicaudatus population in the CP and the EFP showed a relatively stable monthly population, except in June which was likely to be influenced by the stress to lay their eggs or chemicals such as the use of pesticides. This change of habitat characteristics and length-weight relationship on M. anguillicaudatus population in rice paddy fields was influenced by farming practices as well as the time of year.

• Journal of Labour Economics
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• v.42 no.4
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• pp.1-29
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• 2019

This study estimates how changes in the female (aged 25 to 54) labor force participation rate (LFPR) following the historical experiences of the US and Japan would alter the future trend of the female economically active population by 2065, compared to the case in which the LFPR as of 2018 will remain unchanged. According to the results, the female labor force aged 25 to 54 will increase by 14% (about 797,000) and 15% (about 831,000), respectively, by 2042 if the female LFPR should change following the past trends of the US and Japan. In particular, the increase in the labor force is expected to be pronounced among females aged 30 to 44 who currently suffer high rates of job severance. The results of this study strengthen the prediction that the on-going population changes will not reduce much the overall economically active population in the near future. The result of a simulation based on the historical experiences of Japan suggests that, as least in the near future, policy efforts to encourage female labor supply will be more effective in alleviating the potential labor-market impacts of population changes, compared to policies aiming at increasing old-age employment.

• Journal of the Korean Geographical Society
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• v.47 no.1
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• pp.98-120
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• 2012

The main objective of this study is to conduct subnational population projections of Korea based on a multiregional cohort-component method. This objective is accomplished by: (i) establishing a viable framework to implement the multiregional cohort-component method with reference to the Markov chain model and Rogers' multiregional population projection model; (ii) applying the established framework to subnational population projections of Korea, 2005~2030. The main results are twofold. First, the proposed method turns out to be highly valid in a methodological sense, which is seen from a high level of coincidence between the estimated and the observed. Second, the projection results turn out to be highly useful in the sense that interregional migration flow matrices are resulted for projection periods. The projected migration flows are expected to provide invaluable information for an understanding of future population change and for a formulation of policy alternatives. This study is strongly inspired by the multiregional perspective emphasizing the evolution of multiple regional populations interconnected by interregional migration flows rather than the overall national change.

• Industry Promotion Research
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• v.6 no.1
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• pp.79-86
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• 2021

Due to the change in the demographic structure, the problem of low birth rate and aging population leads to a serious decrease in human resources, and the necessity of introducing foreign workers is increasing. This study believes that the introduction of foreign workforce is the most effective to expand the working-age population in the era of low birthrate and aging, when demographic changes begin in earnest, and to this end, it sought to devise measures to improve the legal system for migrant workers. As a result of this study, first, the legal system for migrant workers should be unified and improved. It is necessary to establish or unify management agencies so that the 「Immigration Control Act」 and the 「Labor Act」 can establish a cooperative relationship. Second, the 「Immigration Control Act」 should be revised to make it easier for migrant workers to find employment. It is necessary to positively review the employment permit system and acquisition of nationality. Third, there should be no equity or discrimination against migrant workers. Under the principle of mutual benefit, employers and migrant workers should not be equally discriminated against. Fourth, the social insurance system must be added to the legal system of migrant workers. Therefore, the legal system should be reorganized so that migrant workers are not discriminated against in various insurance systems including the four major social insurance systems. In conclusion, the problem of low birthrate and aging population has become a serious social problem due to changes in the demographic structure, and the decrease in the possible generation population has reached a level of concern. The importance of migrant workers' employment and work environment is increasing. Nevertheless, related legal and institutional problems still exist, and measures to improve the legal system for migrant workers are needed.

• Journal of Life Science
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• v.9 no.6
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• pp.646-652
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• 1999

The effect of temperature on the structure change of the SH of myosin head have been investigated with improved resolution by x-ray diffraction using synchrotron radiation. The movement of myosin head and conformational change of contractile molecules were occurred in the muscle contraction. IASL (iodo acetamide) and MSL (maleimide) disordered the orderly helix arrangement of myosin in the rest state of spin level. The temperature effect on the structure change was great at the UL in the equatorial reflection. But those of IASL and MSL were minor. Equatorial reflection (10, 11) change inferred that myosin head was moved to the vicinity of actin filament by temperature change (from $25^{\circ}C$ to $0^{\circ}C$) at UL, but spin level was not changed. The intensity change of 143 $\AA$ and 72 $\AA$ could offer information of the mass profection of population of myosin heads along the filament axis. The slope of intensity profile of the mass profection of 143$\AA$ and reflection of MSL is appeared sharply and those of UL and IASL were not changed. The decrease of MSL actin reflection at 51 $\AA$ and 59 $\AA$ in the actin reflection change refers that the shifted myosin head binds a certain actin or changes an actin structure. From these results, we could conclude that IASL and MSL were spin labeled on SH of myosin head and disordered the helix arrangement of actin.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.6
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• pp.115-126
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• 2022

The study's goal is to determine the amount of climate change's impact on ethnic minority (EM) households' livelihoods, as well as their adaptability to climate change and long-term viability. The research was conducted in Vietnam's Northwestern Sub-region, where ethnic minorities account for more than half of the overall population. The study uses a combination of qualitative and quantitative methods based on a survey of 480 households in 04 provinces severely affected by climate change in the Northwest sub-region of Vietnam. The results show that: climate change (extreme weather events) occurs with increasing frequency, mainly affecting the life expectancy, health, and capital of households; Vulnerable groups (women, ethnic minorities) have a poor adaptive capacity and mainly suffer the consequences of shocks, are afraid to change their livelihoods; Microfinance plays an important role in enhancing the sustainability of livelihoods through increasing capital and financial assets and reducing the vulnerability of ethnic minority households. Finally, research has some solutions for microfinance - special credit specifically for ethnic minority households in the Northwest Sub-region: support for microfinance advice, home credit with transition orientations to adapt to climate change response and relieves its impact on the social lives.