• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.3
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• pp.138-149
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• 2008

Rapid accumulation of carbon dioxide in the atmosphere for the past century leads to acidify the surface ocean and contributes to the global warming as it forms acid in the ocean and it is a green house gas. In order to curb the green house gas emissions, in particular carbon dioxide, various multilateral agreements and programs have been established including UN Convention of Climate Change and its Kyoto Protocol for the last decades. Also a number of geo-engineering projects to manipulate the radiation balance of the earth have been proposed both from the science and industrial community worldwide. One of them is ocean fertilization to sequester carbon dioxide from the atmosphere through the photosynthesis of phytoplankton in the sea. Deliberate fertilization of the ocean with iron or nitrogen to large areas of the ocean has been proposed by commercial sector recently. Unfortunately the environmental consequences of the large scale ocean iron fertilization are not known and the current scientific information is still not sufcient to predict. In 2007, the joint meeting of parties of the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter, 1972 and 1996 Protocol (London Convention/Protocol) has started considering the purposes and circumstances of proposed large-scale ocean iron fertilization operations and examined whether these activities are compatible with the aims of the Convention and Protocol and explore the need, and the potential mechanisms for regulation of such operations. The aim of this paper is to review the current development on the commercial ocean fertilization activities and management regimes in the potential ocean fertilization activities in the territorial sea, exclusive economic zone, and high seas, respectively, and further to have a view on the emerging international management regime to be London Convention/Protocol in conjunction with a support from the United Nations General Assembly through The United Nations Open-ended Informal Consultative Process on Oceans and the Law of the Sea.

• The Journal of Industrial Distribution & Business
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• v.1 no.1
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• pp.13-21
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• 2010

Since Korea establish diplomatic ties with China in 1992, korea and China have had rapid progress in most of field as politic, economy, society and culture through basing on cultural commonality and geographical adjacency. Especially, China is the biggest trading partner to korea, and also Korea is third-biggest trading country to China. They become strategic cooperating relation in 2008. Currently, in terms of international trade relation, WTO/DDA negotiation is proceeding in difficulty, but FTA has been growing and extending in the world, and the two country, china and korea, have been competitively trying wide and active FTA negotiation promotion. After Financial crisis in 1997, according to the requirement of local economic cooperation, China has shown the interest to several countries since the conclusion of FTA treaty with ASEAN in 2005. China also makes the active afford to conclude FTA with Korea. Last May 28th, this was mentioned in the meeting between president Lee and Premier Wen Jiabao, so it is anticipated that the negotiation for FTA will be started in the near future. There are many political suggestions and concerns in terms of way of negotiation korea would choose. Some economist said that "'Continuous FTA aimed at long-term protocol should be promoted between korea and China and negotiated includingly'" However, this research claims that commodity exchange, service, and investment areas should be included and it has to be comprehensive package settlement style in negotiation. This research has found out the characteristics of China's negotiation and implications through the China's existed FTA negotiation examples. Currently, China has taken Continuous or a phase-negotiation method to ASEAN, Pakistan, Chile and some other developing country and to advanced countries like New Zealand or Singapore, comprehensive package settlement method is used in FTA negotiation. In consider of the FTA negotiation between Korea and China, Korea has some problems in the commodity change area in agriculture maket's opening. While, for china, the issues would happen in service trade area, especially when encountering finance and communication industries are opened, China's economy could be exposed to some risk. In result, Korea should expand its negotiation range from commodity trade to service trade, in order to exchange both issues, then the negotiation will be concluded more easily. In other word, for FTA, korea should follow comprehensive package settlement way that is similar to New zealand and Singapore case. Through this kind of method, Korea can expect effect of creating trade, conversion of it and preoccupancy of service field in china's market against the advanced countries like Usa, Europe and Japan. Also, to have a successful FTA negotiation, korea should find out china's policy for FTA negotiation. With this information, korea will be able to suggest the way to make a profit. Systematic analysis and comparison about previous negotiation cases of china are needed before the negotiation begin.

• Current Research on Agriculture and Life Sciences
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• v.8
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• pp.129-138
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• 1990

This study investigated the relationship between the cutflow of rural population and agricultural policy by using time series method. For the analytical tools, decomposition time series methods and regression technique were employed in computing seasonal fluctuation and cyclical fluctuation of population migration. Also, this study predicted farmhouse, rural population till the 2000's by means of the mathematical methods. The analytical forms employed in forecasting farmhouse, rural population were Exponential curve, Gompertz curve and Transcendental form. The major findings of this study were identified as follows: 1) Rural population and farmhouse population began to decrease from 1965 and hastily went down since 1975. Rural population which accounted for 36.4 percent, 35.6 percent of national population respectively in 1960 diminished about two times: 17.5 percent, 17.1 percent respectively. 2) The rapid decreasing of the rural population was caused because of the outflow of rural people to the urban regions. Of course, that was also caused from the natural decreases but the main reason was heavily affected more the former than the latter. In the outflowing course shaped from rural to the urban regions, rural people concentrated on such metropolis as Seoul, Pusan, Keanggi. But these trends were diminishing slowly. On the other hand, compared with that of the 1970's the migration to Keanggi was still increasing in the 1980's. That is, people altered the way of migration from the migration to Seoul, Pusan to the migration to the out-skirts of Seoul. 3) The seasonal fluctuation index of population migration has gone down since the June which the request of agricultural labor force increases and has turned to be greatly wanted in the March as result of decomposition time series method. As result of cyclical analysis, the cyclical patterns of migration have greatly 7 cycle. 4) As result of forecasting the rural and farmhouse population, rural and farmhouse population in the 2000 will be about 9,655(thousand/people) and 4,429(thousand/people) respectively. Thus, it is important to analyze the probloms that rural and farmhouse population will decrease or increase by the degree. But fairly defining the agricultural into a industry that supply the food, this problem - how much our nation need the rural and farmhouse population - is greatly significant too. Therefore, the basic problems of the agricultural including the outflows of rural people are the earning differentials between rural and urban regions. And we should regard the problems of the gap of relative incomes between rural and urban regions as the main task of the agricultural policy and treat the agricultural policy in the viewpoint of developing economic equilibrium than efficiency by using actively the natural resources of the rural regions.

• Journal of Intelligence and Information Systems
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• v.24 no.3
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• pp.21-44
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• 2018

In recent years, the rapid development of internet technology and the popularization of smart devices have resulted in massive amounts of text data. Those text data were produced and distributed through various media platforms such as World Wide Web, Internet news feeds, microblog, and social media. However, this enormous amount of easily obtained information is lack of organization. Therefore, this problem has raised the interest of many researchers in order to manage this huge amount of information. Further, this problem also required professionals that are capable of classifying relevant information and hence text classification is introduced. Text classification is a challenging task in modern data analysis, which it needs to assign a text document into one or more predefined categories or classes. In text classification field, there are different kinds of techniques available such as K-Nearest Neighbor, Naïve Bayes Algorithm, Support Vector Machine, Decision Tree, and Artificial Neural Network. However, while dealing with huge amount of text data, model performance and accuracy becomes a challenge. According to the type of words used in the corpus and type of features created for classification, the performance of a text classification model can be varied. Most of the attempts are been made based on proposing a new algorithm or modifying an existing algorithm. This kind of research can be said already reached their certain limitations for further improvements. In this study, aside from proposing a new algorithm or modifying the algorithm, we focus on searching a way to modify the use of data. It is widely known that classifier performance is influenced by the quality of training data upon which this classifier is built. The real world datasets in most of the time contain noise, or in other words noisy data, these can actually affect the decision made by the classifiers built from these data. In this study, we consider that the data from different domains, which is heterogeneous data might have the characteristics of noise which can be utilized in the classification process. In order to build the classifier, machine learning algorithm is performed based on the assumption that the characteristics of training data and target data are the same or very similar to each other. However, in the case of unstructured data such as text, the features are determined according to the vocabularies included in the document. If the viewpoints of the learning data and target data are different, the features may be appearing different between these two data. In this study, we attempt to improve the classification accuracy by strengthening the robustness of the document classifier through artificially injecting the noise into the process of constructing the document classifier. With data coming from various kind of sources, these data are likely formatted differently. These cause difficulties for traditional machine learning algorithms because they are not developed to recognize different type of data representation at one time and to put them together in same generalization. Therefore, in order to utilize heterogeneous data in the learning process of document classifier, we apply semi-supervised learning in our study. However, unlabeled data might have the possibility to degrade the performance of the document classifier. Therefore, we further proposed a method called Rule Selection-Based Ensemble Semi-Supervised Learning Algorithm (RSESLA) to select only the documents that contributing to the accuracy improvement of the classifier. RSESLA creates multiple views by manipulating the features using different types of classification models and different types of heterogeneous data. The most confident classification rules will be selected and applied for the final decision making. In this paper, three different types of real-world data sources were used, which are news, twitter and blogs.

• Korean Journal of Materials Research
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• v.8 no.7
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• pp.621-627
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• 1998

The formation of Co-silicide between Co/Zr bilayer on the amorphous and crystalline Si substrates has been investigated. The films of Zr(50$\AA$) and Co(l50$\AA$) were deposited with e-beam evaporation system and were heattreated with the rapid thermal annealing system at the temperatures between 50$0^{\circ}C$ and 80$0^{\circ}C$ with 10$0^{\circ}C$ increments for 30 seconds. The phase identification of Co-silicide was carried out by XRD and the chemical analysis was examined by AES and RBS. The interface morphologies of Co/Zr bilayer films were investigated by cross sectional TEM and HRTEM. $CoSi_2$ was formed epitaxially on the crystalline Si substrate above $700^{\circ}C$ while polycrystalline $CoSi_2$ was grown on the amorphous Si substrate. The formation temperature of Co-silicide on the amorphous Si substrate was about 100 C lower than that on the crystalline Si. The COzSi phase was not identified on the both Si substrates. The formation temperature of first phase of Co-silicide on ColZr bilayer was higher than that on Co mono layer. CoSizlayer formed on the amorphous Si substrate exhibits better uniformity compared to the CoSiz formed on the crystalline substrate. The sheet resistance of CoSiz layer on crystalline Si was lower than that on the amorphous Si at high temperatures.tures.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.4
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• pp.281-286
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• 2009

Introduction: Enamel matrix derivative (EMD) is a protein which is secreted by Hertwig root sheath and plays a major role in the formation of cementum and attachment of peridontium. Several studies have shown that EMD promoted the proliferation and differentiation of preosteoblasts, osteoblasts and periodontal ligament cells in vitro: however, reports showing the inhibition of osteogenic differentiation by EMD also existed. This study was designed to simultaneously evaluate the effect of EMD on the two cell lines (human mesenchymal stem cells: hMSC, human periodontal ligament derived fibroblasts: hPDLCs) by means of quantitative analysis of some bone related matrices (Alkaline phosphatase : ALP, osteopontin ; OPN, osteocalcin ; OC). Materials and Methods: hMSCs and hPDLCs were expanded and cells in the 4${\sim}$6 passages were adopted to use. hMSc and hPDLCs were cultured during 1,2,7, and 14 days with 0, 50 and 100 ${\mu}g/ml$ of EMD, respectively. ALP activity was assessed by SensoLyte ALP kit and expressed as values of the relative optical density. Among the matrix proteins of the bony tissue, OC and OPN were assessed and quantification of these proteins was evaluated by means of human OC immunoassay kit and human OPN assay kit, respectively. Results: ALP activity maintained without EMD at $1,2^{nd}$ day. The activity increased at $7^{th}$ day but decreased at $14^{th}$ day. EMD increased the activity at $14^{th}$ day in the hPDLCs culture. In the hMSCs, rapid decrease was noted in $7^{th}$ and $14^{th}$ days without regard to EMD concentrations. Regarding the OPN synthesis in hPDLCs, marked decrease of OPN was noted after EMD application. Gradual decrease tendency of OPN was shown over time. In hMSCs, marked decrease of OPN was also noted after EMD application. Overall concentration of OPN was relatively consistent over time than that in hPDLCs. Regarding the OC synthesis, in both of hPDLCs and hMSCs, inhibition of OC formation was noted after EMD application in the early stages but EMD exerted minimal effect at the later stages. Conclusion: In this experimental condition, EMD seemed to play an inhibitory role during the differentiation of hMSCs and hPDLCs in the context of OC and OPN formation. In the periodontium, there are many kinds of cells contributing to the regeneration of oral tissue. EMD enhanced ALP activity in hPDLCs rather than in hMSCs and this may imply that EMD has a positive effect on the differentiation of cementoblasts compared with the effect on hMSCs. The result of our research was consistent with recent studies in which the authors showed the inhibitory effect of EMD in terms of the differentiation of mineral colony forming cells in vitro. This in vitro study may not stand for all the charateristics of EMD; thus, further studies involving many other bone matrices and cellular attachment will be necessary.

• Korean Journal of Environment and Ecology
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• v.22 no.3
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• pp.309-319
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• 2008

Roads are an indicator of anthropogenic activity causing ecosystem disturbances and often lead to habitat fragmentation, habitat loss, and habitat isolation. The Hallasan National Park(153.4$km^2$) on Jeju Island being distinguished for its unique geology, topography, and biota has also been designated as a core area of UNESCO Man and the Biosphere(MAB) Reserve. Although the high conservation value of this park has contributed to a rapid growth of tourists and road construction, landscape changes due to roads have not been examined yet. We used GIS systems to examine the fragmentation pattern caused by roads, in relation to its zonation, elevation, and vegetation. When a buffer was applied to roads(112m width for paved roads and 60m width for both legal and illegal trails), the park consisted of 100 fragments. The ten fragments generated after applying buffer to only paved roads and legal trails ranged from $0.002km^2$ to $38.2km^2$ with a mean of $14.2km^2$, and about 7% of both nature conservation zone and nature environment zone of the park were edge. Fragments in both east and west ends of the park and around the summit exhibited relatively high shape indices with means of 5.19(for 100 fragments) and 7.22(for 10 fragments). All five legal trails are connected to the pit crater of the mountain and vegetation changed from broadleaf forests and conifer forests to grasslands with elevation, consequently resulting in dramatic fragment size reduction in grasslands at high elevation, in particular above 1,400m, where endemic and alpine plants are abundant. These results show that in Hallasan National Park the risks of habitat deterioration and habitat loss due to fragmentation may be more severe in the nature conservation zone dominated by Baengnokdam than in the nature environment zone. Therefore, current road networks of the park appear to fall short of the goal of the national park for ecosystem conservation and protection. Considering that the entire Hallasan National Park also serves as a MAB core area, conservation efforts should focus, first of all, on park rezoning and road management to mitigate habitat fragmentation.

• Management & Information Systems Review
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• v.36 no.4
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• pp.117-127
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• 2017

In recent times the size of the world IPO in general has skyrocketed. Specifically, China's financial market development is becoming important as both the size of China's capital market and the number of companies going public are gradually increasing. This has led to a rapid development of venture vapital(VC) institutions in China for the past couple of decades. This study focuses on one of the three markets of China's Shenzhen Stock Exchange-the Growth Enterprise Board((GEB) hereafter, ChiNext). The ChiNext is established in October, 2009 to enable hi-tech or high growth potential technology companies that find it relatively difficult to fulfil the listing requirements of either the Shenzhen Main Board or Small and Medium Size Enterprise Board(SMEB) to go public. This study covers a three-year period(2012/01/-2015/01) and analyze first day initial return of 83 venture capital-backed companies and 53 non-venture capital-backed companies using T-test. Regression analysis is used as to examine the variables affecting IPO's first-day return. The empirical results are four-fold. First, the level of first day return of venture-backed is significantly lower than non venture capital backed support in the Chinese venture capital market. Second, the level of first-day return of listed companies supported by foreign venture capital is significantly higher than that of companies receiving domestic venture capital support. Third, the firms that have a large number of venture capital firms showed a low level of first-day return. Fourth, regression result for the IPO first-day return which is as dependent variable indicates that the venture capital support(VCAP), number of venture capital(VCNum), offering size(Lnsize) and PER all affect have negative effect on the first day initial return. Also, the venture capital type(VCType), turnover ratio and the the firm type(Tech-firms) statistically affect IPO first day return positively. Finally, by shedding more light on the IPO first-day return, this paper provides meaningful information to investors about the Chinese IPO market.

• Journal of the Korean earth science society
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• v.41 no.3
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• pp.248-260
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• 2020

Oceanic current maps introduced in science and earth science textbooks can offer a valuable opportunity for students to learn about rapid climate change and the role of currents associated with the global energy balance problem. Previously developed oceanic current maps in middle and high school textbooks under the 2007 and 2009-revised national curriculum contained various errors in terms of scientific accuracy. To resolve these problems, marine experts have constructed a unified oceanographic map of the oceans surrounding the Korean Peninsula. Since 2010, this process has involved a continuous, long-term consultation procedure. By extensively gathering opinions and through verification process, a representative and scientific oceanic current map was eventually constructed. Based on this, the educational oceanic current maps, targeting the comprehension of middle and high school students, were developed. These maps were incorporated into middle and high school textbooks in accordance with the revised 2015 curriculum. In this study, we analyzed the oceanic current maps of five middle school science textbooks and six earth science textbooks that were published in high school in 2019. Although all the oceanic current maps in the textbooks were unified based on the proposed scientific oceanic current maps, there were problems such as the omission of certain oceanic currents or the use of a combination of dotted and solid lines. Moreover, several textbooks were found to be using incorrect names for oceanic currents. This study suggests that oceanic current maps, produced by integrating scientific knowledge, should be visually accurate and utilized appropriately to avoid students' misconception.

• KDI Journal of Economic Policy
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• v.30 no.1
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• pp.1-31
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• 2008

Various opinions have been suggested to explain the slump in equipment investment, such as increased government regulations, shareholder-oriented management by expanded foreign equity investment, response against M&A threats, conservative investment trends seen after a series of bankruptcy of large conglomerates (amidst crumbling myth of "Too Big to Fail"), and financial restructuring. Some also argued that the increased uncertainty in business environment is mainly responsible for conservative management, though there are few domestic studies made regarding the situation. But, in other countries, including the U.S., studies have shown that more volatility is seen now surrounding stock prices, profitability, and sales growth rate reflecting business performance. Also, there are other studies showing such expanded volatility have led to conservative management by businesses. In this regard, this study reviews the volatility conditions of business performance of Korean companies based on profitability, and then attempts to analyze the impact on investment brought on by increased volatility. Each company's profitability volatility used here is from the standard deviation of companies for the past five years. As a profitability indicator, the ROA (= operating profit/total asset) is used. According to the analysis, profitability volatility has remarkably increased from the mid 3% in 1994 to low 5% in 2005. Profitability volatility of the Korean companies has expanded to a great extent since the financial crisis. The crisis might have served to raise the volatility in the macroeconomic conditions. If increased volatility observed during the economic crisis had gradually declined after the crisis, the situation could be interpreted as a temporary phenomenon, not to be too concerned over. But, this was not the case for Korea. The volatility level, after the crisis, has not dropped back to its pre-crisis level. Hence, in the Korea's case, high volatility cannot be explained by the impact of financial crisis. Not only that, the fact that such expansion is seen in every industrial sector indicates that this phenomenon cannot be explained by the composition change of industries alone. An undergoing study shows that with a rapid spread of globalization, industries fiercely competing with China experience more volatility. Such increased volatility tends to contract investment, and since the crisis the impact of volatility on investment has slightly increased. It is noteworthy that this study only includes a part of 'uncertainty' that could be measured statistically. For instance, the profitability volatility indicator used in this study is unable to reflect all the effects that the tacit reduction of protection by the government or regulations might have made. So, the result here also indicates that other 'uncertain' factors not mentioned in this study may have served to contract investment sentiment. It would be impossible for policies to completely remove uncertainties measured by profitability volatility, but at least it is necessary to put effort to reduce the macroeconomic volatility in the future economic management. Stabilized macroeconomic management may not be enough to diminish all volatility that occurs within each company, but it would make a meaningful contribution in encouraging investment.