• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.1
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• pp.1-7
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• 2005

Tidal flats have been regarded to carry out transformation and removal of land-derived organic matter, and this purifying capability of organic matter by tidal flats is one of very important reasons for their conservation. However, integral biogeochemical studies on production and decomposition of organic matter by benthic microbes in tidal flats have been absent in Korea, although the information is indispensable to quantification of the purifying capability. Our major goals in this multidisciplinary research were to understand major biogeochemical processes and rates mediated by diverse groups of microbes dominating material cycles in the tidal flats, and to assess the contribution of benthic microbes to removal of organic matter and nutrients in the tidal flats. Our study sites were Ganghwa and Incheon north-port tidal flats that had been regarded as naturally well reserved and organically polluted, respectively. Our research group measured over 3 years primary production, biomass and community structure of primary producers, abundance and production of bacteria, enzyme activities, distribution of protozoa and protozoan grazing rates, rates of denitrification and sulfate reduction, early sediment diagenesis, primary production and respiration based on oxygen microelectrode. We analyzed major features of each biogeochemical process and their interactions. The results are compiled in the following articles in this special issue: An (2005), Hwang and Cho (2005), Mok et at. (2005), Na and Lee (2005), Yang et at. (2005), and Yoo and Choi (2005).

• Korean Journal of Ecology and Environment
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• v.47 no.4
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• pp.319-327
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• 2014

Understanding and quantifying of carbon storage in ecosystem is very important factor for predicting change of global carbon cycle under the global climate change. We estimated total ecosystem carbon in Gyeryongsan National Park with naturally well preserved ecosystem in Korea. Vegetation of Gyeryongsan National Park was classified with mainly four communities with Quercus mongolica (1,743.5 ha, 38.0%), Quercus variabilis (1,174.0 ha, 25.6%), Quercus serrata (971.9 ha, 21.2%), Pinus densiflora (695.2 ha, 15.2%). Biomass and soil carbons were calculated from biomass allometric equations based on the DBH and carbon contents of soil and litter collected in quadrat in each community. The tree biomass carbon was in Quercus variabilis ($130.1tCha^{-1}$), Pinus densiflora ($111.1tCha^{-1}$), Quercus mongolica ($76.2tCha^{-1}$), Quercus serrata ($39.0tCha^{-1}$). Soil carbon storage was in Quercus mongolica ($159.7tCha^{-1}$), Quercus serrata ($121.0tCha^{-1}$), Pinus densiflora ($110.5tCha^{-1}$), Quercus variabilis ($90.8tCha^{-1}$). Ecosystem carbon storage was Pinus densiflora ($239.9tCha^{-1}$), Quercus mongolica ($235.9tCha^{-1}$), Quercus variabilis ($226.0tCha^{-1}$), Quercus serrata ($165.9tCha^{-1}$), total amount was $867.7tCha^{-1}$. The area of each vegetation carbon storage was Quercus mongolica ($411,200tCha^{-1}$), Quercus variabilis ($265,300tCha^{-1}$), Pinus densiflora ($166,800tCha^{-1}$), Quercus serrata ($161,200tCha^{-1}$) and the total ecosystem carbon amount estimated $1,045,400tCha^{-1}$ at Gyeryongsan National Park. Theses results indicate that different in naturally well preserved ecosystem.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.500-507
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• 2016

This study was undertaken to improve the survival and early life growth rates of cold-water fish by culturing rotifer (Brachionus plicatilis) with low-temperature tolerance. The enrichment experiment was carried out at different temperatures and over different time intervals. Cultivation of the rotifer at low temperatures was repeated, with the selected and cultured as the water temperature was gradually lowered from $20^{\circ}C$ to $10^{\circ}C$. Enrichment of the rotifer was completed using A, S, SCV and SCP. Enrichment was carried out after 6, 12 and 24 hours at three different temperatures (10, 15 and $20^{\circ}C$). In the growth experiments, the rotifer increased to approximately triple their original size, from $350{\pm}7.9ind./ml$ to $1,064{\pm}5.7ind./ml$ at $10^{\circ}C$ over 50 days. The fatty acid composition of the four enrichment materials was species-specific, with the highest ratios belonging to eicosapentaenoic acid (EPA, C20:5n-3) and docosahezaenoic acid (DHA, C22:6n-3) in SCP. The fatty acid composition of the rotifers was affected by the enrichment materials. The EPA (% of total fatty acid) was more than 2 % in SCP, which showed a higher ratio than the other enrichment materials. DHA was higher in S reaching 12.40 % at $15^{\circ}C$ for 24 hours. The highest levels of EPA (3.09 %) and DHA (11.65 %) were obtained after the rotifers were enriched with S at $20^{\circ}C$ for 12hours.

• Management & Information Systems Review
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• v.37 no.2
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• pp.1-21
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• 2018

According to the results of the FKI's ethical management status and CSR promotion status, about 95% of domestic companies enact the Code of Ethics, while 64% of companies operating systems for communication and dialogue with stakeholders in the process of CSR activities, It seems that strategic CSR activities of domestic companies have not been fully established yet compared with the introduction of ethical management. Even if companies conduct CSR activities strategically, there is very little CSR level of the companies that consumers perceive. This is because the psychological mechanism of CSR on consumers' perceptions is too complicated and detailed, resulting in a positive result and a negative result depending on the investigator's research method. So far, there have been many studies on the direct impact of CSR on corporate evaluation, purchase intention, and corporate image. However, there are few studies on the effect of CSR and CA on purchase intention through product attitude. Therefore, The purpose of this study is to demonstrate the effect of corporate social responsibility(CSR) and corporate Ability(CA) on the purchase intention through product attitudes perceived by consumers, and the moderating effect of corporate reputation between product attitude and purchase intention. As a research method, we selected 4 companies, such as Samsung etc, who have been conducting CSR for the past 10 years, as a sample. The relationship between the CSR and the corporate competence of these companies on purchasing intention was examined through questionnaires for general consumers. The results of this study show that CSR and CA have a positive effect on product attitude, and consumers' product attitude has a positive effect on purchase intention. In addition, CSR and CA were found to have a positive (+) effect on purchase intention through consumer attitude. Finally, it is found that the reputation of the firm has a moderating effect on the relationship between consumer's product attitude and purchase intention. This study suggests that CSR should be strategically promoted in order to positively shape the attitude of consumers toward products of companies and their companies. As a theoretical implication, this study showed that the effect of CSR activities and CA on consumer's product attitude and purchase intention, centered on mediating effects of product attitude and corporate reputation discrimination.

• Korean Journal of Mineralogy and Petrology
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• v.33 no.1
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• pp.1-10
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• 2020

The atomic structures of silicate liquids at high pressure provide insights into the transport properties including thermal conductivities or elemental partitioning behavior between rocks and magmas in Earth's interior. Whereas the local electronic structure around silicon may vary with the arrangement of the nearby oxygens, the detailed nature of such relationship remains to be established. Here, we explored the atomic origin of the pressure-induced changes in the electronic structure around silicon by calculating the partial electronic density of states and L₃-edge X-ray absorption spectra of SiO₂ polymorphs. The result showed that the Si PDOS at the conduction band varies with the crystal structure and local atomic environments. Particularly, d-orbital showed the distinct features at 108 and 130 eV upon the changes in the coordination number of Si. Calculated Si XAS spectra showed features due to the s,d-orbitals at the conduction band and varied similarly with those observed in s,d-orbitals upon changes in the crystal structures. The calculated Si XAS spectrum for α-quartz was analogous to the experimental Si XRS spectrum for SiO₂ glass, implying the overall similarities in the local atomic environments around the Si. The edge energies at the center of gravity of XAS spectra were closely related to the Si-O distance, thus showing the systematic changes upon densification. Current results suggest that the Si L_2,3-edge XRS, sensitive probe of the Si-O distance, would be useful in unveiling the densification mechanism of silicate glasses and melts at high pressure.

• The Journal of the Petrological Society of Korea
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• v.25 no.4
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• pp.373-388
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• 2016

To understand human activity in the past, the information about past environmental change including geomorphological and climatic conditions is essential and this can be traced by using age dating and geochemical analysis of sediments from the prehistoric sites. The sedimentary sequence of Seokgwan-dong Paleolithic Site located in Seoul was 5m long unconsolidated sediments and consists of lower part bedrock weathering sediments, slope deposits and upper-part fluvial deposits. In this study, upper part sediments were used to reconstruct past environmental change through age dating and various physical and chemical analyses including grain size, magnetic susceptibility and mineral and elements. The fluvial sediments can be divided into 4 units including three organic layers. Grain size analysis results showed that the sediments were very poorly sorted with fining upward features. Magnetic susceptibility was relatively high in the organic layers, indicating environmental changes causing mineral composition change at that times. The mineral and major element composition are similar to Jurassic biotite granite which mainly consists of quartz, K-feldspar, biotite and muscovite. The radiocarbon age of $14,240{\pm}80yr$ BP was obtained from the lower most organic layer of Unit III(O), suggesting that the fluvial sediments formed at least from the early stage of deglacial period after the end of Last Glacial Maximum. Subsequent wet and warm climates and resultant fluvial process including slope sedimentation during the Holocene may have been responsible for the sedimentary sequence in Seokgwan-dong paleolithic site and surrounding area. The observed organic layers suggests frequent wetland occurrence combined with natural levee changes in this area.

• Journal for History of Mathematics
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• v.22 no.3
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• pp.1-30
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• 2009

Frege's logicism has been frequently regarded as a development in number theory which succeeded to the so called arithmetization of analysis in the late 19th century. But it is not easy for us to accept this opinion if we carefully examine his actual works on real analysis. So it has been often argued that his logicism was just a philosophical program which had not contact with any contemporary mathematical practices. In this paper I will show that these two opinions are all ill-founded ones which are due to the misunderstanding of the theoretical place of Frege's logicism in the context of contemporary mathematical practices. Firstly, I will carefully examine Cantorian definition of real numbers and Frege's critiques of it. On the basis of this, I will show that Frege's aim was to produce the purely logical definition of ratios of quantities. Secondly, I will consider the mathematical background of Frege's logicism. On the basis of this, I will show that his standpoint in real analysis was much subtler than what we used to expect. On the one hand, unlike Weierstrass and Cantor, Frege wanted to get such real analysis that could be universally applicable. On the other hand, unlike most mathematicians who insisted on the traditional conceptions, he would not depend upon any geometrical considerations in establishing real analysis. Thirdly, I will argue that Frege regarded these two aspects - the independence from geometry and the universal applicability - as those which characterized logic itself and, by logicism, arithmetic itself. And I will show that his conception of real numbers as ratios of quantities stemmed from his methodological maxim according to which the nature of numbers should be explained by the common roles they played in various contexts to which they applied, and that he thought that the universal applicability of numbers could not be adequately explicated without such an explanation.

• Journal of Hospice and Palliative Care
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• v.5 no.2
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• pp.94-100
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• 2002

Purpose : The system to refer terminally ill patients to palliative or hospice care which ultimately give them emotional, psychological, and social support hasn't been fully developed and organized yet in Korea. The controversies concerning the current referral system are being analyzed to present the improvements. Methods : The questionnaires were asked to be filled out by family members of the 76 patients by phone interview, who were referred from the Seoul National University Hospital between April, 2001 to March, 2002. They were referred to the 35 palliative and hospice care-giving institutes and hospitals which were given questionnaires by mail. Results : Of the 76 patient's family members, 47 family members accepted to answer the questionnaire. The first thing that influence to family to determine the referral of patient was solicitation of doctors or nurses (44%). And they were influenced by allowance for the other things such as convenience of patients (32%), convenience of caring family members (24%). In the course of determining of referred institutes, responders had considered at first their dwelling area, and then fame of institutes, the place which patent had wanted to spend last hours or which is suitable for patient's funeral service, and their financial condition. Thirty-eight the 47 responders answered that they had experienced difficulties in referral procedure. The worst among difficulties was unwanted discharge, and followings were lack of information about the referred institutes, concern about patient's suffering, resistance of patient and opposition of other family members, etc. Although they expressed dissatisfaction in referral procedure, most of them answered they had been satisfied with hospice care at referred institute after referral. Merits of referral which responders counted were patient's peace, caring family's comfort and reduced cost in order. Of the 35 referred institutes, 24 institutes' staffs responded mail questionnaires and sent to us in return. Except one responder, the rest approved the referral system and thought that referred patients had been satisfied with their hospice care. And they claimed that systemic support of the government is definitely necessary. The most difficult thing which responders experienced in care of referred patients was lack of information about patients. Besides, there were patient's financial problems, lack of understanding about their institutes of patients or family, and inconvenience of terminal cancer patient's pain control. Conclusion : The development and support of the organized referral system is needed to alleviate the troubles which patients, family members, and palliative or hospice institutes and hospitals have to face through the procedure of the referral.

• Korean Journal of Ecology and Environment
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• v.53 no.3
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• pp.229-240
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• 2020

In this study, the results of fish assemblage survey for 16 reservoirs in the Yeongsan·Seomjin-River watershed were presented with fish assemblage characteristics analysis in relation to reservoir size. The survey method including number of sampling sites was followed the "Biomonitoring survey and assessment manual" of the Ministry of Environment/National Institute of Environmental Research (MOE/NIER), and the reservoirs were categorized as three size groups, small, medium or large reservoirs, based on the MOE/NIER as well. Total 13 family classified into 44 species were collected from 2018 (7 reservoirs) to 2019 (9 reservoirs), and the dominant and subdominant species were Hemiculter eigenmanni (Relative abundance, RA, 32.9%) and Lepomis macrochirus (RA, 31.4%), respectively. As a result of the analysis in relation to the reservoir size, the average (±standard deviation) number of species of the small, medium and large reservoirs were 11±2.9, 14.3±2.1, 22.7±0.6, respectively, which showed positive correlation with the reservoir size. Total 6 fish assemblage characteristics(number of species, number of individuals, richness index, herbivorous fish ratio, carnivorous fish ratio, exotic fish ratio) showed significant differences between the each reservoir size groups (P<0.05). As a result of cluster analysis, 16 reservoirs were clustered into 5 groups with 60% similarity, and the each reservoirs seems to be clustered depends on the distance from each other, watershed and their historical geology rather than size. These results are baseline information for the understanding of fish assemblage in Korean reservoirs, important for establishing management policy of reservoirs in the Yeongsan·Seomjin-River watershed.

• Korean Journal of Environmental Agriculture
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• v.33 no.2
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• pp.86-102
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• 2014

BACKGROUND: According to the types of human interference, there are various plants that have strong vitality and ability to breed in the dry field. Recently, climate change alters the geographical distribution and phenology of the plant species. So, we need to understand present occurrence pattern and ecological characteristics of these plants. METHODS AND RESULTS: The plant species data were obtained from 8 regions in Jeolla-do. Flora investigation was done from May 2013 to September 2013. Habitat type of dry field in Jeolla-do was classified into 3 types (inside of dry field: IDF, embankment around the end of a dry field: EDF, levee slope of dry field: LS). The vascular plants of study area were listed 296 taxa which contain 68 families, 203 genera, 244 species, 43 varieties and 9 forms. The vascular plants of three different habitat types were IDF 174 taxa, EDF 249 taxa and LS 136 taxa. The occurrence rate of Therophyte was arranged by the order of IDF(67.6%), EDF(51.9%), LS(54.3%). Naturalized rate was analysed as IDF 27.9%, EDF 21.0%, LS 18.6%. Urbanization index was analysed as IDF 11.8%, EDF 13.7%, LS 10.0%. CONCLUSION: With these results, we found that three habitat types were ecological difference affected by the human impacts. Also, we found environmental indicators through the ecological characteristics of flora for the type of habitat of dry field. These indicators will help assess the agriculture environmental variability and the floral change according to the climate change in dry field.