• Korean Journal of Construction Engineering and Management
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• v.18 no.4
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• pp.3-16
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• 2017

Forecasting cash flow is very important but is difficult and complicated to analysis in high-rise development projects. And An expected value which was forecasted on the early stage is likely to fluctuate due to uncertainties around such complicated huge project to consider the probable uncertainty. There are not objectified method which are able to cope with uncertainty of project, and feasibility study based on selected financial analysis does not include liquidity of cash flow. Through such a stochastic method, developer can cope with cash flow fluctuation and set up a financial plan. Also this study is meaningful for laying the foundation for high-rise development project and feasibility study as well as the suitability and accuracy of feasibility study. Analysis showed that NPV and IRR include residential apartments shows surplus revenue as return of apartments offset deficit of hotel and office. Factors influencing the project feasibility for high-rise development project are sales account of $1^{st}$ year and annual vacancy rate of office.

• Journal of The Korean Association For Science Education
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• v.18 no.2
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• pp.137-148
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• 1998

This study compared the innovative characteristics of science teachers who participated in the First Student Science Inquiry Olympic and those of science teachers who did not participate in the event. The subjects were science teachers in three groups: (1) the active participants in the Inquiry Olympic who supervised the students contestants, (2) the observers of the Inquiry Olympic who came to see the event, and (3) the ordinary teachers who did not come to the Inquiry Olympic and were sampled through stratified cluster sampling. The study instrument was a questionnaire; all the subjects received the survey questionnaire by mail. The return rate was 45%. In general, the Inquiry Olympic participants(both the student supervisors and the observers) demonstrated different characteristics from the nonparticipants in four categories. Firstly, the Inquiry Olympic participants showed higher level of self actualization, for example, interest in science education, higher inner motivation, stronger desire to innovate than did the nonparticipants. Secondly, the participants demonstrated more involvement in professional activities and greater degree of upward social mobility than the nonparticipants. Thirdly, the participants had communication behaviors different from nonparticipants, e. g.. greater leadership of public opinions, more experience of contact with the change agent, greater tendency to regard their school society as modern. Lastly, the participants had higher social status than the nonparticipants. Implications and suggestions are made for the utilization of the innovation-oriented science teachers to implement of innovations in the future.

• Journal of Korean Society of Forest Science
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• v.97 no.3
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• pp.305-315
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• 2008

Payments for Environmental (or Ecosystem) Services (PES) are emerging as new conservation policy tools. The basic concept underlying PES is that users pay to providers of environmental services for ensuring the continual provision of services based on the voluntary contracts. The purpose of this paper is to introduce the concepts and types of PES and to design a pilot PES scheme for biodiversity/ecosystem conservation on Genetic Reserve Forest in Korea. Genetic Reserve Forest is one of the protected areas designated in Korea to maintain forest biodiversity. PES is designed for the pine forests only in Genetic Reserve Forest, which corresponds to 943 ha. Service providers are to manage their forests based on the contracts in ways that maintain and enhance forest biodiversity and receive the payments in return. The payments are calculated as the sum of management, monitoring, and opportunity costs, resulting 1,140,378 won/year/ha (it corresponds to approximately $1,227 based on the 2007 average exchange rate 1$ = 929.2 won). Because PES are relatively new policies, however, more work needs to be done. Future work includes researches on the correlation between forest biodiversity and management practices and the economic evaluation of forest biodiversity. In addition, enhancing awareness on PES and education of stakeholders are warranted to further develop the scheme.

• Korean Journal of Construction Engineering and Management
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• v.16 no.2
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• pp.65-76
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• 2015

The Clean Development Mechanism (CDM) is the multi-lateral 'cap and trade' system endorsed by the Kyoto Protocol. CDM allows developed (Annex I) countries to buy CER credits from New and Renewable (NE) projects of non-Annex countries, to meet their carbon reduction requirements. This in effect subsidizes and promotes NE projects in developing countries, ultimately reducing global greenhouse gases (GHG). To be registered as a CDM project, the project must prove 'additionality,' which depends on numerous factors including the adopted technology, baseline methodology, emission reductions, and the project's internal rate of return. This makes it difficult to determine ex ante a project's acceptance as a CDM approved project, and entails sunk costs and even project cancellation to its project stakeholders. Focusing on hydro power projects and employing UNFCCC public data, this research developed a prediction model using logistic regression and CART to determine the likelihood of approval as a CDM project. The AUC for the logistic regression and CART model was 0.7674 and 0.7231 respectively, which proves the model's prediction accuracy. More importantly, results indicate that the emission reduction amount, MW per hour, investment/Emission as crucial variables, whereas the baseline methodology and technology types were insignificant. This demonstrates that at least for hydro power projects, the specific technology is not as important as the amount of emission reductions and relatively small scale projects and investment to carbon reduction ratios.

• Journal of Nutrition and Health
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• v.57 no.3
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• pp.349-364
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• 2024

Purpose: This study used the Analytic Hierarchy Process to evaluate the relative importance of the factors that school nutrition teachers and dietitians consider during menu planning for school foodservices across various educational levels. Methods: An online survey was conducted from December 2023 to January 2024. The hierarchical structure for school foodservice menu management was developed through content analysis, consisting of five high-level categories and 3-4 low-level factors. Questionnaires were distributed to 395 nutrition teachers and dietitians from kindergarten, elementary, middle, and high schools nationwide. One hundred and sixty-six responses were received, resulting in a 42.0% return rate. These responses were analyzed using Microsoft Excel and SPSS Statistics. Results: The most commonly referenced sources for school foodservice menu planning were 'menus obtained from websites' (19.4%). The most significant challenge encountered was 'incorporating students' preferences' (18.6%). In the hierarchy of categories considered for school foodservice menu management, 'employees and facilities' ranked highest (0.2347), followed by 'preference' (0.2312), 'nutrition balance' (0.2027), 'cooking process' (0.1726), and 'food materials' (0.1588). Within each category, the top-ranked factors were 'employees' cooking skills' (0.3759), 'students' preferences' (0.4310), 'dietary reference intakes' (0.4968), 'foodservice hygiene' (0.4374), and 'food costs' (0.4213). The study also compared the relative importance of factors according to the educational levels, and the top-ranked factors were the same across all educational levels. In particular, 'students' preferences', 'dietary reference intake', and 'food costs' aligned with the top three challenges in school foodservice menu planning. Conclusion: Enhancing working conditions for school foodservice employees and developing menu planning methods that accommodate students' preferences are necessary. These findings will provide foundational data for future school foodservice menu management strategies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.390-397
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• 2017

The introduction of exotic fish species may reduce the number of native fish species and disturb the aquatic ecosystem. Therefore, measures to block and manage fish species are required. Accordingly, a fish species blocking system using bubbles was developed in this study to block exotic fish species. An experimental channel was produced and the possibility of blocking such exotic fish species was evaluated. The bubble generator is a system that produces a bubble curtain by generating air with an air compressor that blocks fish species. Bluegill, which is an exotic fish species in the country, was tested with this generator. The size of bluegill was between 0.10 m and 0.15 m and the depth of water was maintained at 0.70 m. The flow velocity of the experiment channel was classified into 3 levels (0.20 m/s, 0.10 m/s, and 0.05 m/s) considering the natatorial ability of the fish species. The results revealed that 70.07% of bluegill showed movements to swim upstream before applying the bubble, but it is considered that the ascending rate would be higher given that the fish species thinks downstream is a habitat and showed almost no movement. However, when the blocking facility was installed, most fish species showed movements to return to the downstream again by the bubble curtain, indicating a very high blocking effect. In particular, when the generating bubble was terminated, the fish species swam back to the upstream area very soon, so the fish species blocking effect using the bubble was excellent.

• Journal of Navigation and Port Research
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• v.43 no.4
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• pp.264-272
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• 2019

In this study, the rate of return on investment used as a proxy variable for the entity's value and financial structure (liability ratio) is related to positive balance. This is consistent with the Static Tradeoff Theory (STT) that the entity's value and financial structure are related to a positive balance because the capital expense of a debt (tax-saving effects) that is less than its equity cost before it is in financial difficulty. Also, operating profitability (EBITDA/Sales), investment safety, total asset growth, net working capital and depreciation expenses are related to negative (-) with financial structure (liability ratio). This is the result of an analysis consistent with the Pecking Order Theory (POT). Fuel costs, borrowing, total asset turnover, financial costs, and tangible asset ratios have a significant positive relationship with the debt ratio. This is consistent with the agency theory and confirms that excessive chartering expenses, such as the bankrupt H company, are the main factors that pressure the financial structure of Korean ocean carriers.

• Resources Recycling
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• v.31 no.3
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• pp.40-52
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• 2022

This study analyzed the amount of carbon dioxide reduction and economic benefits of detailed processes of CO₂ 6,000 tons plant facilities with mineral carbonation technology using carbon dioxide and coal materials emitted from domestic circulating fluidized bed combustion power plants. Coal ash reacted with carbon dioxide through carbon mineralization facilities is produced as a complex carbonate and used as a construction material, accompanied by a greenhouse gas reduction. In addition, it is possible to generate profits from the sales of complex carbonates and carbon credits produced in the process. The actual carbon dioxide reduction per ton of complex carbonate production was calculated as 45.8 kgCO₂eq, and the annual carbon dioxide reduction was calculated as 805.3 tonCO₂, and the benefit-cost ratio (B/C Ratio) is 1.04, the internal rate return (IRR) is 10.65 % and the net present value (NPV) is KRW 24,713,465 won, which is considered economical. Carbon mineralization technology is one of the best solutions to reduce carbon dioxide considering future carbon dioxide reduction and economic potential.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.6
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• pp.413-419
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• 2023

Light Emitting Diodes(LEDs) are widely utilized not only in lighting but also in various applications such as mobile phones, automobiles, displays, etc. The integration of LED lighting with communication, specifically Visible Light Communication(VLC), has gained significant attention. This paper presents the direct implementation and experimentation of a Vehicle-to-Vehicle(V2V) Visible Light Communication system using commonly used red and yellow LEDs in typical vehicles. Data collected from the leading vehicle, including positional and speed information, were modulated using Non-Return-to-Zero On-Off Keying(NRZ-OOK) and transmitted through the rear lights equipped with red and yellow LEDs. A photodetector(PD) received the visible light signals, demodulated the data, and restored it. To mitigate the interference from fluorescent lights and natural light, a PD for interference removal was installed, and an interference removal device using a polarizing filter and a differential amplifier was employed. The performance of the proposed visible light communication system was analyzed in an ideal case, indoors and outdoors environments. In an outdoor setting, maintaining a distance of approximately 30[cm], and a transmission rate of 4800[bps] for inter-vehicle data transmission, the red LED exhibited a performance improvement of approximately 13.63[dB], while the yellow LED showed an improvement of about 11.9[dB].

• Journal of Wetlands Research
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• v.17 no.1
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• pp.80-90
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• 2015

Variability of precipitation pattern and intensity are increasing due to the urbanization and industrialization which induce increasing impervious area and the climate change. Therefore, more severe urban inundation and flood damage will be occurred by localized heavy precipitation event in the future. In this study, we analyze the future frequency based precipitation under climate change based on the regional frequency analysis. The observed precipitation data from 58 stations provided by Korea Meteorological Administration(KMA) are collected and the data period is more than 30 years. Then the frequency based precipitation for the observed data by regional frequency analysis are estimated. In order to remove the bias from the simulated precipitation by RCP scenarios, the quantile mapping method and outlier test are used. The regional frequency analysis using L-moment method(Hosking and Wallis, 1997) is performed and the future frequency based precipitation for 80, 100, and 200 years of return period are estimated. As a result, future frequency based precipitation in South Korea will be increased by 25 to 27 percent. Especially the result for Jeju Island shows that the increasing rate will be higher than other areas. Severe heavy precipitation could be more and more frequently occurred in the future due to the climate change and the runoff characteristics will be also changed by urbanization, industrialization, and climate change. Therefore, we need prepare flood prevention measures for our flood safety in the future.