• Korean Journal of Environment and Ecology
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• v.26 no.3
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• pp.333-341
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• 2012

To investigate the feeding habits of the Kaloula borealis, the stomach contents of 52 out of 56 specimens collected around Daejung-up, Jeju Island in June 2011 were studied. The stomach contents were analyzed with the stomach flushing method. According to the results, the main preys of the Kaloula borealis were Diptera sp., Harpalidae, Formicidae and Drosophilidae. the Kaloula borealis of all sizes fed on small preys, while individuals with large SVL fed on big preys. By feeding on a large amount of food with a small number of activities, the individuals with large SVL is considered to enhance energy efficiency. In many cases, the Kaloula borealis fed on Diptera sp. or Drosophilidae, which are slow but active and capable of flying. As a result, the Kaloula borealis take the sit-and-wait form of preying rather than actively searching for food. The results of this research on feeding habits of the Kaloula borealis will provide valuable resources to protect the endangered Kaloula borealis experiencing a sharp decline in their population and to prepare plans for population preservation strategies for them.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.11
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• pp.1536-1540
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• 2006

Crossbreeding effects for wool quality traits viz. greasy fleece weight (kg), staple length (cm), average fibre diameter (${\mu}$) and medulation percentage were estimated using the Dickerson's and Kinghorn's models. The data analyzed involved 15 genetic groups including Nali purebred, $F_1$'s of two and three breeds, $F_2$'s and reciprocal crossbred obtained from the crossing of Nali (N), Merino (M) and Corriedale (C) breeds during 1980-96. Nali and Corriedale breeds had non-significant negative additive genetic effects (Dickerson's model) on greasy fleece weight, while effects of Corriedale were negative for staple length only from both models. In general additive genetic effects of all three breeds were non-significant for all the wool traits except medulation percentage. Non significant heterotic and recombination effects (epistatic loss) were estimated from both models. However, the estimates of crossbreeding effects varied between the models both in magnitude as well as in direction barring few exceptions. Undesirable positive heterosis was found on medulation percentage for all types of combinations involving three breeds. Comparison of least squares means of various genetic groups revealed that both two breed and three breed crosses were superior to the Nali breed for all wool quality traits. Fibre diameter of MN crossbreds was significantly less than CN crossbreds. Results also indicated that as the inheritance of Nali breed in a cross is decreased, the medulation percentage decreases which is desirable. Inter se mating of crossbreds (two breed, three breed) has not resulted in a decline in the wool quality traits. These results indicate that the synthetic population derived from three breeds can be stabilized easily for wool traits as there may not be epistatic loss on subsequent inter se mating of crossbreds.

• Journal of Korean Neurosurgical Society
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• v.59 no.2
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• pp.149-153
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• 2016

Objective : The aim of the present study is to estimate the incidence trend of head injury and the mortality based on traffic accident statistics and to investigate the impacts of rapid industrialization and economic growth on epidemiology of head injury in Korea over the period 1970-2012 including both pre-industrialized and post-industrialized stages. Methods : We collected data of head injury estimated from traffic accident statistics and seven hospital based reports to see incidence trends between 1970 and 2012. We also investigated the population structure and Gross National Income (GNI) per capita of Korea over the same period. The age specific data were investigated from 1992 to 2012. Results : The incidence of head injury gradually rose in the 1970s and the 1980s but stabilized until the 1990s with transient rise and then started to decline slowly in the 2000s. The mortality grew until 1991 but gradually declined ever since. However, the old age groups showed rather slight increase in both rates. The degree of decrease in the mortality has been more rapid than the incidence on head injury. Conclusion : In Korea during the low income stage, rapid industrialization cause considerable increase in the mortality and the incidence of head injury. During the high income stage, the incidence of head injury gradually declined and the mortality dropped more rapidly than the incidence due to preventive measures and satisfactory medical care. Nevertheless, the old age groups revealed rather slight increase in both rates owing to the large population structure and the declining birth rate.

• Journal of Korean Public Health Nursing
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• v.7 no.1
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• pp.1-16
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• 1993

The objective of this study is to review the role and function of the village health worker in the wake of the recent social changes in Korea. The stud}' also aimed at' elucidating' the characteristics of the village health worker organizations developed through community participation in this country. The study methods employed were: a review of literature and other existing information related to VHW's activities ; the use of Questionnaire and interview with VHW's on their activities in one selected county in 1992. The major findings obtained are as follows: 1. So far the community health care activities have been carried out by medical colleges, foreign aid agencies and religious organizations with a view to improving health care for the population in rural area. 2. The VHWs employed by the local community health services received remuneratiorin cash or in kind. However, presently no remuneration is paid to VHWs employed by the government village health projects. The training for VHWs is organized by County Health Center once a year for 1-2days regardless of pre-employment or refresher. 3. The needs of care for maternal and child health and family planning has been decline due to the decrease of the target population, but on the other hand, the needs of care by VHW for prevention of infectious diseases, health of the aging, management of geriatric diseases, prevention of poisoning of pesticides and environmental sanitation has beer increased. 4. It was felt strongly that the training for VHWs should be strengthened by means of developing a problem-solving oriented educational program in order to improve practical skills of VHWs.

• Journal of Korean Society of Rural Planning
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• v.18 no.4
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• pp.45-60
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• 2012

The purpose of this study is to approach for the flow analysis of changing central-place functions and basic demands between the central city and the small town. Under the rural society progressed, this study examines how the small town changes in the relation to the central city. The subject of study is based on changes in demand for retail and hospitality. The small town is providing basic demands and urban services primary for the rural in the settlement system. Because of the rural depopulation and the aging of society, Retail and hospitality in the rural is reducing of the facility followed. But the majority of related researches are stocks approach. These studies are useful to find out the characteristic of small town, but is difficult to consider the influence of the central city. In this situation after this study using the function index is set up a concept model, it examines for the basis of changes in demand for the small town. The result of the analysis is that the changes of retail and hospitality are more severe in the more small town than in the central city. Whereas the small town with a population decline is consistent with the reduced number of branches, Population growth in the central city is reduced to the number of the Number of branches. The central-place function has been strengthened in the central city. While the younger generation, recreation, etc. related retail are disappearing rapidly, the mainstream of small town is grocery, home improvement, restaurants.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.2
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• pp.52-61
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• 2001

At least, there are intense pressures on the natural habitats from various disturbance, including urbanization, extension of industrial area, and road construction. These human land use result in fragmentation of landscape and natural habitat. The ecological consequences of habitat fragmentation include the direct effects of habitat loss and the indirect effects of reduced inter-patch dispersal. The decline of biological diversity has been rapidly declined by the habitat loss and fragmentation. Conservation strategists should consider not only the habitat amount of that must be preserved, but also the spatial configuration of habitat across the landscape. But, the paucity of available data for most species forces landscape ecologists to develop the concept, model, and theory. The developed theories are often misused in academic papers and practical applications. The development history, presumption of concept, model, theory is ignored. This tendency have leaded to failure of landscape restoration and the use of theory in conservation practice have come under increasing attacks. This paper will highlight the ecological theory that have proven the most influential in landscape ecology, restoration and conservation : the theory of island biogeography, the theory of nested subset analysis, minimum viable population(MVP), the theory of metapopulation dynamics. And, it find the problem and usefulness of four theory in application to real world. Consequently, the understanding of theoretical implication about landscape ecological theory is required. We must carefully apply the theory after examining the problem and availability of various theory because of no existence of only one general theory.

• Journal of the Korean association of regional geographers
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• v.16 no.2
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• pp.123-136
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• 2010

To grasp the migration characteristics in the Busan Metropolitan Area (BMA), this study analyzed household characteristics and migration selectivity. The major findings of the study are as follows: first, young (especially 25 to 34 years of age) and single person households have greater propensity to migrate out from BMA, and their home ownership rate is low. These trends are much stronger in households that migrate out towards the Seoul Metropolitan Area from Busan. Second, age and educational selectivity of migration is evident. The characteristics of movers are quite different from those of stayers at Busan. Young people are more likely to migrate out of Busan, and higher levels of education are deeply associated with higher mobility. Through analyzing four high schools in Busan, it is acknowledged that most honor students entered 4-year universities in Seoul. The outflow of highly educated young people may induce the brain drain. Busan is undergoing both population decline and the problems caused by the brain drain.

• Journal of Labour Economics
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• v.37 no.4
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• pp.143-157
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• 2014

The purpose of this study is twofold. First, it shows how to calculate the size of nonregular workers in Korea using the supplemental surveys to the Economically Active Population Surveys. Second, it decomposes the difference in the share of nonregular workers between 2005 and 2013 by a Oaxaca-type method.. The obtained results indicate that the differences in coefficients rather than the differences in characteristics are mainly responsible for the decline in the share of nonregular workers. This implies that a worker with the same characteristics is more likely to be a regular worker in 2013 than in 2005. This tendency may come from the changes in workers's as well as firms' employment practices. Also, it is suspected that the Nonregular Worker Act enacted in 2007 may have contributed to the decrease in the share of nonregular workers.

• Korean Journal of Ichthyology
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• v.21 no.sup1
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• pp.29-37
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• 2009

The tiny fragment of freshwater body is providing home for huge biodiversity and resources for the existence of human. The competing demand for freshwater have been increased rapidly and it caused the declination of biodiversity in recent decades. Unlike the natural process of extinction in gradual progress, the current species extinction is accelerated by human activity. As a result many fish species are already extinct or alive only in captivity in the world and about fifty eight animal species are in endangered in Korea including eighteen freshwater species. Conservation of biodiversity is the process by which the prevention of loss or damage is attained, and is often associated with management of the natural environment. The practical action is classified into in-situ, or ex-situ depending on the location of the conservation effort. Recovery means the process by which the status of endangerment is improved to persist in the wild by re-introduction of species from ex-situ conservation population into nature or translocation of some population. However there are a lot of restrictions to complete it and successful results are known very rare in case. In this article the authors explore some strategies for conservation and restoration of freshwater fish species conducted in Korea for few years. The major causes are discussed in relation with the decline of freshwater fish diversity during few decades and some strategies are evaluated to advance the process of conservation. A study on the Korean bullhead, Pseudobagrus brevicorpus, is introduced as a case for ex-situ conservation and restoration in freshwater ecosystem.

• Journal of the korean society of oceanography
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• v.33 no.1-2
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• pp.35-40
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• 1998

In February and April 1997, three temporary interruptions of electric power production at the Uljin Nuclear Power Plant in the east coast of Korea were caused by the malfunction of the cool-ing-water supply unit. The clogging of the drum screens inside the unit caused by the surface swarm of the euphausiid Euphausia pacifica Hansen might be responsible for the malfunction. These incidents were of particular interest since such interruption of reactors' operation by krill swarms had not previously been reported. Using samples caught by the drum screens inside the cooling water-supply unit, we investigated the population structure of surface swarms. One occasion of nighttime and three occasions of daytime surface swarms were found in February and April 1997, respectively. The foreguts of more than 60% of E. pacifica in nighttime surface swarm were in full condition. This evidence suggests that E. pacifica aggregates to the surface water at night for feeding. In daytime surface swarms consisting of mature E. pacifica, however, foreguts in full condition were only found in less than 10eio of krill examined, suggesting that daytime surface swarms are closely related to breeding activity. During the study period, the growth rate of mature females was more than twice higher than that of mature males. Analyses of the sex-ratio and length-frequency data show a decrease in the portion of males with increasing size. There was a decline in the number of males of 19 mm in length. Energy loss during spermatophore transfer may result in the death of male E. pacifica, as found in male E. superba.