• Economic and Environmental Geology
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• v.50 no.6
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• pp.537-544
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• 2017

Stable carbon isotope ratio of carbon dioxide (${\delta}^{13}C_{CO2}$) is used as an important indicator in the researches for global climate change and carbon capture and sequestration technology. The ${\delta}^{13}C$ value has been usually analyzed with Isotope Ratio Mass Spectrometer (IRMS). Recently, the use of Laser Absorption Spectrometry (LAS) is increasing because of the cost efficiency and field applicability. The purpose of this study was to suggest practical procedures to prepare laboratory reference gases for ${\delta}^{13}C_{CO2}$ analysis using LAS. $CO_2$ gas was adjusted to have the concentrations within the analytical range. Then, the concentration of $CO_2$ was assessed in a lab approved by the Korea Laboratory Accreditation Scheme and the ${\delta}^{13}C_{CO2}$ value was measured by IRMS. When the instrument ran over 12 hours, the ${\delta}^{13}C$ values were drifted up to ${\pm}10$‰ if the concentration of $CO_2$ was shifted up to 1.0% of relative standard deviation. Therefore, periodical investigation of analytical suitability and correction should be conducted. Because ${\delta}^{13}C_{CO2}$ showed the dependency on $CO_2$ concentration, we suggested the equation for calibrating the concentration effect. After calibration, ${\delta}^{13}C_{CO2}$ was well matched with the result of IRMS within ${\pm}0.52$‰.

• Journal of Bio-Environment Control
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• v.9 no.3
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• pp.166-170
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• 2000

Three methods for heat collection, which were the flat solar collector, two fan with radiator, and square pipe method, were studied to sue efficiently solar energy in the three different glasshouses for two years. The flat plate solar collector method was made use of the commercial solar collector with collection area of 24$m^2$, the method of two fans with radiators collected solar energy at the top of the glasshouse. An thermal storage tank was constructed underneath in teach glasshouses. When an area of 1,000$m^2$ was heated to the minimum temperature of 9$^{\circ}C$, the decrease rate of heating fuel for the flat plate solar collector, the fan attached radiator and the square pipe methods were 7%, 19% and 28% respectively. The flat plate solar collector method, which could be heated approximately 40-50$m^2$, was currently used by most of the farmer. Under the condition, the decrease rate of annual heating fuel was 14% which was not better for an economic annual heating fuel. If the fan with radiator method was operated, the use of installation and maintenance were required. So, it could not be good economic efficiency of solar heating. The heating efficiency of the square pipe method was relatively better thant those of the flat plate solar collector or the fan attached radiator. Since the cost of materials and its installation of the use of square pipe method was lower than any other method. However, corrosion of the pipe, greater shade in the greenhouse and strength against the square pipe were problems that should be overcome in the square pipe method.

• KDI Journal of Economic Policy
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• v.31 no.1
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• pp.105-138
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• 2009

Although the decline in fertility rate is generally observed along the history of economic development throughout the world, the continuing decline hitting below the replacement level in Korea over the recent years gathered serious social concerns on the ground that it accelerates the process of population aging. The total fertility rate in Koreareached 2.08 in 1983, and gradually fell to the levels of 1.08 in 2005 and 1.26 in 2007. The policy debate over the role of the government has been focused mainly on the level of theoretical discussion without substantial basis on firm empirical evidence and the determinants of fertility. The objective of the paper is to empirically investigate the fertility effect of the female wage, which is understood as one of the most important determinants of fertility in Koreasince 1980 focusing on one aspect of fertility, namely birth spacing. Using the Korean National Fertility Survey conducted in 2006, I estimate a duration model of first and second births taking into account individual heterogeneity, which turned out to be an important factor to control for. Compared with previous studies in the literature on the Korean fertility, the study has an advantage of using the complete pregnancy history of women in a more representative sample. Unlike the previous studies, the analysis also deals with the endogeneity of marriage by treating a certain age, rather than age at marriage, as the time in which a woman becomes exposed to the risk of pregnancy. The study shares the common problem in the literature on birth spacing of lacking relevant wage information for respondents in a retrospective survey. I estimate the wage series as a function of the basic characteristics using the annual Wage Structure Survey from 1980 to 2005, which is considered as a nationally representative sample for wage information of employees. The results suggest that the increase in female wage by 10 percent leads to a decrease in second birth hazard by 0.56~0.92 percentage points and that the increase in spouse's wage by the equal amount is accompanied by the increase in second birth hazard by 0.36~1.13 percentage points. These estimates are more precisely estimated and of smaller magnitude than those presented by the previous studies. The results are robust to the different specifications of the wage equation. The simulation analysis based on the predicted values shows that about 17% of the change in the second birth hazard over the period 1980 to 2005 was due to the change in the female wage. Although there is some limitation in data, the results can be viewed as one estimate of the role of female wage on the recent fertility decline in Korea. The question raised by the paper is not a normative one of whether a government should promote childbearing but a positive one thatexplains fertility decline. Therefore, if there is a wide consensus on promoting childbearing, the finding suggests that the policies designed to reduce the opportunity cost of women in the labor market would be effective. The recent movement of implementing a wide range of family-friendly policies including child care support, maternity leave, parental leave and tax benefit in developed countries should be understood in this context.

• International Commerce and Information Review
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• v.13 no.4
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• pp.177-201
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• 2011

Myanmar had fallen behind other southeast asian nations since Burmese way to Socialism settled down. However, historically second election in Myanmar hold in 2011 and dramatic changes in areas such as Special Economic Zone announcement, the very huge inflows of foreign direct investment in a year of 2009, the infrastructure building projects, a permit of the right to strike for Labour Organization in Myanmar etc. Particularly, Foreign investments and trade with neighbouring countries are actively growing and also with Korea. But investments of Korea in Myanmar relatively are not diversity, with limited sectors such as mining and sewing manufacturing. In this point of view, this paper is trying to make implications for strategies of entry and investments of Korea in Myanmar by using previous papers related to Myanmar economies, trade and foreign investments with updated statistical data. The implications for Korea is that recently Myanmar economy is in its early stages of development. Although it can occur huge demand of railway, road, communications and constructions related to social infrastructures essentially needed for development of a country, these sectors relatively need huge investments. On the other hands, textile and sewing industry relatively need smaller investments in which investors can utilize low labour cost and a position for export to third countries. But those firms which set up for those purpose in Myanmar might have trouble creating domestic markets in future. Moreover, due to demand which occur in the early stage of growth in Myanmar, trade volume tend to increase and trading is also possible to invest but Myanmar still have lots of problems with infrastructure such as road and logistics and we need to make pre-survey for the costs and benefits of our products Finally, Myanmar government is trying to promote and encourage some of industries such as export-oriented industry, import substitution industry and labour-intensive industry. It can also means they will accumulate capital which can be sources for Myanmar economic growth.

• KDI Journal of Economic Policy
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• v.12 no.2
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• pp.81-94
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• 1990

Illegal transactions such as blackmarketing and smuggling allegedly result from too restrictive trade policies. A recent U.S. Senate hearing on the blackmarketing of American goods imported into Korea for the purpose of supporting United States troops and their dependents stationed in Korea concluded with the allegation that Korea's highly restrictive trade practices are responsible for the emergence of the black market. It has also suggested that the removal of such restrictive trade policies would eliminate black market activities. This study addresses the relationship between trade policy and blackmarketing by investigating whether trade liberalization results in the reduction of illegal transactions, and whether the eradication of blackmarketing indeed improves social welfare. When both legally imported goods and illegally exchanged items command the same price, trade liberalization, meaning a decrease in tariff rates or an increase in import quotas, will increase the quantity of legal imports at the expense of illegally transacted goods on the black market. But the price of legally imported goods usually differs from that of illegally sold ones. In this case, a change in the relative prices of these two groups of goods due to a change in trade policy will give rise to income, as well as substitution, effects. Initially, a decrease in the import price due to a decrease in import tax rates or an increase in the allotted quota will reduce illegal transactions, since the decrease in the import price will induce the substitution of legal imports for illegally exchanged, but otherwise, identical goods. On the other hand, the demand for the illegally transacted goods will rise, because of the income effect of the reduced import price. Thus, assuming the positive income effect overwhelms the negative substitution effect, the demand for illegal goods will increase, thwarting the reduction of blackmarketing through trade liberalization. Yet, stepping up the enforcement measures which are geared to preventing blackmarketing itself will drastically reduce the extent of illegal transactions, since it increases the cost of blackmarketing and hence the price of the illegally transacted goods. What this study suggests is that the emergence of the black market in Korea should be attributed more to the excessive supply of duty-free goods imported through U.S. commissaries and exchanges than to the excessive demand for foreign goods. On the other hand, blackmarketing, in most cases, improves economic welfare, since it constitutes an increase in the "actual" amount of imported goods. Suppressing blackmarketing through stepped-up enforcement methods is beneficial only when the substitution effect of the legally transacted goods resulting from the increase in the price of the illegal goods prevails, since the increase in the demand for legal imports must override the decrease in the demand for black market goods as well as the negative income effect.

• Asia pacific journal of information systems
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• v.24 no.4
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• pp.559-575
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• 2014

Individual investors are increasingly flocking to message boards to seek, clarify, and exchange information. Businesses like Seekingalpha.com and business magazines like Fortune are evaluating, synthesizing, and reporting the comments made on message boards or blogs. In March of 2012, Yahoo! Finance Message Boards recorded 45 million unique visitors per month followed by AOL Money and Finance (19.8 million), and Google Finance (1.6 million) [McIntyre, 2012]. Previous studies in the finance literature suggest that online communities often provide more accurate information than analyst forecasts [Bagnoli et al., 1999; Clarkson et al., 2006]. Some studies empirically show that the volume of posts in online communities have a positive relationship with market activities (e.g., trading volumes) [Antweiler and Frank, 2004; Bagnoli et al., 1999; Das and Chen, 2007; Tumarkin and Whitelaw, 2001]. The findings indicate that information in online communities does impact investors' investment decisions and trading behaviors. However, research explicating the correlation between information on online communities and stock market activities (e.g., trading volume) is still evolving. Thus, it is important to ask whether a volume of posts on online communities influences trading volumes and whether trading volumes also influence these communities. Online stock message boards offer two different types of information, which can be explained using an economic and a psychological perspective. From a purely economic perspective, one would expect that stock message boards would have a beneficial effect, since they provide timely information at a much lower cost [Bagnoli et al., 1999; Clarkson et al., 2006; Birchler and Butler, 2007]. This indicates that information in stock message boards may provide valuable information investors can use to predict stock market activities and thus may use to make better investment decisions. On the other hand, psychological studies have shown that stock message boards may not necessarily make investors more informed. The related literature argues that confirmation bias causes investors to seek other investors with the same opinions on these stock message boards [Chen and Gu, 2009; Park et al., 2013]. For example, investors may want to share their painful investment experiences with others on stock message boards and are relieved to find they are not alone. In this case, the information on these stock message boards mainly reflects past experience or past information and not valuable and predictable information for market activities. This study thus investigates the two roles of stock message boards-providing valuable information to make future investment decisions or sharing past experiences that reflect mainly investors' painful or boastful stories. If stock message boards do provide valuable information for stock investment decisions, then investors will use this information and thereby influence stock market activities (e.g., trading volume). On the contrary, if investors made investment decisions and visit stock message boards later, they will mainly share their past experiences with others. In this case, past activities in the stock market will influence the stock message boards. These arguments indicate that there is a correlation between information posted on stock message boards and stock market activities. The previous literature has examined the impact of stock sentiments or the number of posts on stock market activities (e.g., trading volume, volatility, stock prices). However, the studies related to stock sentiments found it difficult to obtain significant results. It is not easy to identify useful information among the millions of posts, many of which can be just noise. As a result, the overall sentiments of stock message boards often carry little information for future stock movements [Das and Chen, 2001; Antweiler and Frank, 2004]. This study notes that as a dependent variable, trading volume is more reliable for capturing the effect of stock message board activities. The finance literature argues that trading volume is an indicator of stock price movements [Das et al., 2005; Das and Chen, 2007]. In this regard, this study investigates the correlation between a number of posts (information on stock message boards) and trading volume (stock market activity). We collected about 100,000 messages of 40 companies at KOSPI (Korea Composite Stock Price Index) from Paxnet, the most popular Korean online stock message board. The messages we collected were divided into in-trading and after-trading hours to examine the correlation between the numbers of posts and trading volumes in detail. Also we collected the volume of the stock of the 40 companies. The vector regression analysis and the granger causality test, 3SLS analysis were performed on our panel data sets. We found that the number of posts on online stock message boards is positively related to prior stock trade volume. Also, we found that the impact of the number of posts on stock trading volumes is not statistically significant. Also, we empirically showed the correlation between stock trading volumes and the number of posts on stock message boards. The results of this study contribute to the IS and finance literature in that we identified online stock message board's two roles. Also, this study suggests that stock trading managers should carefully monitor information on stock message boards to understand stock market activities in advance.

• Journal of Korea Port Economic Association
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• v.31 no.2
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• pp.41-53
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• 2015

In Paracomon Inc. v. Telus Communication, Realice's anchor became entangled with a working fiber-optic submarine cable during its voyage and are presentative of the shipowner(the captain) cut the cable. The owner of the cable brought a claim for the repair cost against the shipowner. The shipowner then advanced a third party claim against a liability insurance underwriter. The Supreme Court of Canada (SCC) held that the shipowner was entitled to limit its liability under the 1976 Convention on the Limitation of Liability for Maritime Claims. The SCC also ruled that even though the misdeed of the shipowner was insufficient to break its right to limitation of liability, its wrongdoing constituted willful misconduct under the 1993 Canada Marine Insurance Act, allowing the underwriter to deny coverage for the incident. Thecasewasthefirsttoaddresstheinterrelationship between the shipowner's right to limit liability under the international convention regime and the availability of liability insurance with respect to such limited liability. This study analyzes the reasoning behind the SCC's judgment and evaluates the appropriateness of this court's decision based on the current maritime industry as well as prevailing maritime law. It concludes that the SCC's decision to declare that the shipowner retained the right to limit its liability is appropriate under the Limitation Convention (1976). However, its declaration that the liability insurer was discharged from liability is not correct in due consideration of the common recognition in the maritime industry, the intended purpose of a third party's right against the liability insurer, and the adoption process of the conduct barring limitation. Based on the SCC's decision, this study finally reviews the issue of the shipowner's right to limit and the coverage of the liability insurer in the Sewol case (2014).

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.858-863
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• 2010

The blueberry farming requires the soil condition of well-drainage, pH of 4.5 to 5.2, and high in organic matters for stable growth and development. Most of soil type of cultivated land in Korea, however, belongs to alkaline soils with low organic matter content and poor drainage. Therefore, the blueberry farmers use peat moss heavily to improve the soil condition, but the guideline on the effective and economic ratio of peat moss is not established yet. This study was performed to determine the cost effective peat moss ratio for amending soils, and to investigate the feasibility of using sawdust and coco peat as soil amendments. Peat moss, coco peat and sawdust are mixed with soil at the ratio of 0, 12.5, 50 and 100% (v/v). Among 3 organic materials with various mixture ratios, the pH of soil was the lowest in 100% peat moss and sawdust mixtures (pH 3.67 and pH 3.73, respectively), followed by pH 5.30 at 50% peat moss. The soil organic matter content are directly proportional to the mixture ratios in all three organic materials and the same trend was observed in the variation of content of exchangeable potassium in the coco peat treatments. On the contrary, the content of available phosphate, exchangeable calcium and magnesium decreased with increasing the ratio of organic materials. The nitrogen content in the leaves decreased as increasing the ratio of peat moss and coco peat in soil, but not of sawdust. The content of phosphate decreased but potassium increased as the ratio of sawdust and coco peat increased. There was no clear difference in the contents of magnesium and calcium among 3 organic materials. The plant height, stem diameter and dry weight of blueberry plants were the highest in 50 % peat moss, followed by 12.5% peat moss and 12.5% coco peat. The plants in 100% peat moss showed very poor growth. It can be concluded that peatmoss, when applied and managed appropriately, will be a good material for improving soil condition as well as securing desirable growth for blueberry. Upon coupling economic aspect, the optimum mixing ratio of peatmoss for blueberry farming is approximately 25-50%.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.4
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• pp.167-178
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• 2021

The purpose of this study is to analyze the direct investment decision factors in the Kaesong Industrial Complex and Vietnam, and to contribute to the creation of domestic jobs and the revitalization of the inter-Korean economy. According to the analysis, most of the Kaesong Industrial Complex and Vietnamese investment companies are entering the complex for the purpose of utilizing cheap labor, cheap factory locations, sales/development of local markets, and bypass export production bases in third countries. This can be divided into production-efficient investors using differences in production price such as labor costs and market-oriented investors to sell and expand the local market, which seems to be consistent with global direct investment patterns such as Nike, Apple, and Amazon. However, even if the North Korea-U.S. denuclearization talks ease or lift sanctions, Vietnamese investors' willingness to invest in the North Korea has been most burdened by the possibility of closing special economic zones due to political risks. Last but not least, it is important to note that those willing to invest in North Korea are mostly smaller enterprises in textiles, sewing, footwear and leather industries-those that benefit from low-cost labor. Since their size is small, they need policy support in financing, especially in the early stages of their business. Even after they grow past the early stages, those without collateral would still need state guarantee letters to get financing. Thus, it is worth considering to use the Inter-Korean Cooperation Fund to compensate commercial banks for bad loan loss or for low-interest loans for smaller SMEs. The interviews with SMEs found that red-tape is one of the biggest difficulties they face. Thus, it is recommended that a one-stop service agency should be established to cover all processes and issues related to inter-Korean economic cooperation to eliminate redundancy and expediate government support for SMEs.

• Ecology and Resilient Infrastructure
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• v.8 no.2
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• pp.120-132
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• 2021

The ecosystem and landscape conservation areas of Seoul were designated according to the Natural Environment Conservation Act and the Natural Environment Conservation Ordinance. With the adoption of the "Rapid Assessment of Wetland Ecosystem Service (RAWES)" approach and the "wetland ecosystem service" for the Ramsar Wetland City Accreditation at the 13th Meeting of the Conference of the Contracting Parties to the Ramsar Convention on Wetlands in 2018, the need for data evaluating wetland ecosystem services has become a necessity. Therefore, in this study, we selected five wetlands from the ecosystem and landscape conservation areas in Seoul, having high ecological conservation values, and evaluated their carbon sequestration and economic value assessment using the InVEST model, which is an ecosystem service evaluation technique. The evaluation results for carbon storage in each wetland are as follows: Tancheon Wetland: 3,674.62 Mg; Bamseom Island in the Hangang River: 1,511.57 Mg; Godeok-dong Wetland: 5,007.21 Mg; Amsa-dong Wetland: 7,108.47 Mg; and Yeouido Wetland: 290.27 Mg. Particularly, the Tancheon Wetland showed the lowest carbon sequestration of 1,130.37 Mg, as compared to the results acquired in 2013, of 4,804.99 Mg. When the average effective carbon rate of $16.06 (US) was applied to the decreased carbon sequestration value, a loss of $15,910.58(US) was calculated. Furthermore, if the average social cost of carbon ($204 (US)) is considered, which includes the impact of climate change on productivity and ecosystems, the total loss is equivalent to $202,101.97 (US). This study aims to examine the natural resource value of urban wetlands by evaluating selected major wetlands in Seoul. This study can be utilized as basic data to plan for the protection and management of the ecosystem and landscape conservation areas. Additionally, because wetland value assessment is considered essential, the results of this study can be used in future research to provide measures for evaluating ecosystem services in the Ramsar Wetland City Certification System. Moreover, this study can be utilized for selecting important wetlands as Ramsar sites, and to raise awareness about the significance of conserving urban wetlands, and for expanding international exchange among the Ramsar Wetland sites.