• Journal of Korean Society of Environmental Engineers
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• v.33 no.6
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• pp.439-446
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• 2011

In this research, enhanced land-cover classification methods using high-resolution satellite image (HRSI) and GIS in terms of practicality and accuracy was proposed. It aims for understanding non-point pollutant origin/loading, assessment the efficiency of rainfall storage/infiltration facilities and sounds water-environment management. The result of applying enhanced land-cover classification methods to the urban region verifies that roof and road area are including various vegetations such as roof garden, flower bed in the median strip and street tree. This accounts for 3% of total study area, and more importantly it was counted as impervious area by GIS alone or conventional indoor work. The feasibility of the method was assessed by applying to rainfall-runoff analysis for three weak rainfall in the range of 7.1-10.5 mm events in 2000, Chiba, Japan. A good agreement between simulated and observed runoff hydrograph was obtained. In comparison, the hydrograph simulated with land-use parameters by the detailed land-use information of 10m grid had an error between 31%~71%, while enhanced method showed 4% to 29%, and showed the improvement particularly for reproducing observed peak and recession flow rate of hydrograph in weak rainfall condition.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.5
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• pp.581-600
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• 2013

The current status of atmospheric environmental impact assessment (EIA) has been summerized and future prospective for effective and accurate atmospheric EIA has been proposed by reviewing available papers and reports for the atmospheric EIA. The number of reports for the EIA in the EIA support system which is operated by the Korean Environmental Institute have been dramatically decreased from 282 reports in 2008 to 113 reports in 2012 during recent five years. This is partially due to simplification of the EIA procedure, the contraction of the public development and economic recession. We analyzed details of the EIA report to review how actual atmospheric EIA has preformed according to the EIA guidelines from the Korean Ministry of Environment. The 264 reports of EIA published in 2011 and 2012 had been reviewed especially focusing on the atmospheric evaluation items such as meteorology, air quality measurement and modeling, odor measurement and modeling, wind corridor in urban planning, and climate change. In overall sense, the atmospheric EIA has been performed quite well by abiding the guidelines except for local meteorological data measurement, permit standard for air quality and wind corridor. The new approaches to improve the procedure of atmospheric EIA and to reflect future of national air quality standard of $PM_{2.5}$ have been proposed. The guidelines on how to evaluate the wind corridor, to implement atmospheric EIA for $PM_{2.5}$ permit, and how to acquire local meteorological data by combining local measurement and model prediction are required for the effective and future oriented atmospheric EIA.

• The Journal of Society for e-Business Studies
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• v.17 no.1
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• pp.111-136
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• 2012

The global recession has made it more difficult for companies to invest in IT, and they are increasingly aware of the environmental costs of so doing. In these circumstances, cloud computing has emerged as a new paradigm in the business IT sector. Governments, institutes and companies around the world, as well as specifically in Korea since 2009, have turned to this model of providing IT resources. This study is concerned to identify those characteristics of cloud computing that affect its introduction on a company's part; it offers a theoretical framework describing cloud services and seeks to establish causal linkages between antecedent factors and a company's introduction and application of this form of IT provision. The features of cloud computing in particular contexts that the study selected for analysis were its scalability, speed, security, potential compatibility with existing services, efficiency, economic feasibility, dependency and credibility. The study thus related these to whether or not cloud computing was adopted, verifying adjustment effects for cloud services. On the basis of a survey of enterprise IT decision-makers, it emerged through a statistical analysis of correlations that cloud computing's efficiency, economic feasibility and credibility had an effect on its introduction. This study's results should be of use to vendors and potential purchasers of cloud computing services. It is one of the first pieces of research on cloud computing from the customer perspective, based on the perceived characteristics of cloud services as they are seen and valued by users.

• Korean Journal of Construction Engineering and Management
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• v.15 no.1
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• pp.39-50
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• 2014

After the global financial crisis, domestic construction industry has gone through a rapid recession. This resulted in gradual market shift towards architectural remodeling. Architectural remodeling not only improves residential environment but it has many advantages such as increase of each unit's exclusive area, free space within the horizontal or extension of an annex building, and increase number of household through splitting the household of bigger pyeong, etc. However, in case of the Korean market for apartment remodeling, due to various regulations and problem with business promotion procedures, majority of business is slow despite the figure that remodeling volume is not that small. Also, feasibility study which decides to push ahead public house remodeling business will have a flaw using net present value's law; it has a flaw of not considering properties of each phase of remodeling business and future's uncertainty. Hence, this research will improve the problem of traditional value assessment method of net present value's law. It will also consider one of the real options such as binomial model in order to supplement NPV which is used in current feasibility study. This research was based on real successful cases of public house remodeling and it was possible for feasibility study which was more realistic and valid. This research provided foundation for development of Korean public house remodeling market. There is high anticipation of increasing the validity by improving the problems of current feasibility study and economic efficiency assessment.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2541-2549
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• 2013

The Construction industry has been dealing with much trouble due to global economic recession and domestic political trends emphasizing on welfare than development. Consequently, domestic construction market has been dramatically shrunk during the last a few years, and international market has become the only potential solution for the industry. However, there has been lack of efforts in developing a quantified measure of global competencies for Korean engineering and construction organizations. This study attempted to develop quantified indices for Korean engineering and construction contractors with which the level of global construction competencies can be objectively monitored. In doing so, a survey questionnaire was developed to identify relative importances of core competency elements which were derived from extensive literature reviews and experts interviews. AHP (Analytic Hierarchy Process) was employed as a main analysis method in developing quantification measures. The analysis results reveal little differences in competency requirements between engineering and construction firms and it implies that the global market becomes more integrated and requires a total solution for a construction project. The developed core competency measures can be used to quantify the level of preparedness of Korean engineering and construction firms at the time of evaluation and also be used as a basis for performance benchmarking indicators if they are compared with business showings.

• Publications of The Korean Astronomical Society
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• v.27 no.4
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• pp.297-298
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• 2012

ANIR (Atacama Near InfraRed camera) is a near infrared camera for the University of Tokyo Atacama 1m telescope, installed at the summit of Co. Chajnantor (5,640 m altitude) in northern Chile. The high altitude and extremely low water vapor (PWV = 0.5 mm) of the site enable us to perform observation of hydrogen $Pa{\alpha}$ emission line at $1.8751{\mu}m$. Since its first light observation in June 2009, we have been carrying out a $Pa{\alpha}$ narrow-band imaging survey of nearby luminous infrared galaxies (LIRGs), and have obtained $Pa{\alpha}$ for 38 nearby LIRGs listed in AKARI/FIS-PSC at the velocity of recession between 2,800 km/s and 8,100 km/s. LIRGs are affected by a large amount of dust extinction ($A_V$~ 3 mag), produced by their active star formation activities. Because $Pa{\alpha}$ is the strongest hydrogen recombination line in the infrared wavelength ranges, it is a good and direct tracer of dust-enshrouded star forming regions, and enables us to probe the star formation activities in LIRGs. We find that LIRGs have two star-forming modes. The origin of the two modes probably come from differences between merging stage and/or star-forming process.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5163-5168
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• 2012

The aim of this study is to develop the supply-demand model(dynamic recursive simulation model) on the Hallabong tangor. In order to analyze the effects of alternative policy scenarios on the Hallabong tangor sector. Simulation runs were experimented for the period, 2011~2021, with three different scenarios. The major simulation results are as follows. The results of baseline show that in the year, 2021, acreage, production, price received by farm would be 2,051.5ha, 62,049.1 ton, 2,537.4 won per kg respectively. The results of scenario I (shipping control scenario) show that in the year, 2021, acreage, production, price received by farm would be 2,079.4ha, 62,984.9 ton, 2,836.3 won per kg respectively. The results of scenario II(the rate of economic growth 3.5%) show that in the year, 2021, acreage, production, price received by farm would be 2,039.5ha, 61,647.5 ton, 2,417.3 won per kg respectively. Finally, The results of scenario III(Survey of experts) show that in the year, 2021, acreage, production, price received by farm would be 2,053.7ha, 62,124.4 ton, 2,574.8 won per kg respectively. Therefore, economic recession can be a negative role in the industrial growth and price of Halabong tangor, but expansion of Hallabong tagor's export and processing can be a very positive role in the industrial growth and price of Halabong tangor.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.91-102
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• 2020

This study constructed production frontiers of inputs and outputs in a sequential manner, measured inefficiencies by applying a non-radial sequential weighted Russell directional distance function to these frontiers, and analyzed Luenberg productivity indices and the contribution of each of input and output factor based on these distances. The results are as follows. First, the productivity of banks increased due to technical changes after the global financial crisis. Second, productivity growth decreased between 2009 and 2014 due to technical changes after the recession, as previous studies have shown that technology progressed before the global financial crisis but then largely decreased or remained the same thereafter. After 2014, the productivity of banks improved. This result may be due to both technology improvement after 10 years of stagnation and reduction of inputs and non-performing loans. Third, the 3.6% annual of productivity growth for 10 years was comprised of 1.77% household loans, 0.67% corporate loans, 0.98% manpower, 1.18% non-performing loans, -0.5% total deposits, and -1.25% securities. Finally, this study has limitations since it could not control risks such as capital structure and interest volatility.

• Journal of Distribution Science
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• v.12 no.4
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• pp.31-39
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• 2014

Purpose - This study investigates the following two issues. First, we attempt to find the important determinants of housing investment and to identify their significance rank using survey panel data. Recently, the expansion of global uncertainty in the real estate market has directly and indirectly influenced the Korean housing market; households demonstrate a sensitive reaction to changes in that market. Therefore, this study aims to draw conclusions from understanding how the impact of financial strength of the household is related to house investment. Second, we attempt to verify the effectiveness of diverse indices of financial strength such as DTI, LTV, and PIR as measures to monitor the housing market. In the continuous housing market recession after the global crisis, the government places top priority on residence stability. However, the government still imposes forceful restraints on indices of financial strength. We believe this study verifies the utility of these regulations when used in the housing market. Research design, data, and methodology - The data source for this study is the "National Survey of Tax and Benefit" from 2007 (1st) to 2011 (5th) by the Korea Institute of Public Finance. Based on this survey data, we use panel data of 3,838 households that have been surveyed continuously for 5 years. We sort the base variables according to relevance of house investment criteria using the decision tree model (DTM), which is the standard decision-making model for data-mining techniques. The DTM method is known as a powerful methodology to identify contributory variables for predictive power. In addition, we analyze how important explanatory variables and the financial strength index of households affect housing investment with the binary logistic multi-regressive model. Based on the analyses, we conclude that the financial strength index has a significant role in house investment demand. Results - The results of this research are as follows: 1) The determinants of housing investment are age, consumption expenditures, income, total assets, rent deposit, housing price, habits satisfaction, housing scale, number of household members, and debt related to housing. 2) The impact power of these determinants has changed more or less annually due to economic situations and housing market conditions. The level of consumption expenditure and income are the main determinants before 2009; however, the determinants of housing investment changed to indices of the financial strength of households, i.e., DTI, LTV, and PIR, after 2009. 3) Most of all, since 2009, housing loans has been a more important variable than the level of consumption in making housing market decisions. Conclusions - The results of this research show that sound financing of households has a stronger effect on housing investment than reduced consumption expenditures. At the same time, the key indices that must be monitored by the government under economic emergency conditions differ from those requiring monitoring under normal market conditions; therefore, political indices to encourage and promote the housing market must be divided based on market conditions.

• The Journal of Engineering Geology
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• v.23 no.2
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• pp.137-147
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• 2013

For the effective management of groundwater resources, it is necessary to predict groundwater level fluctuations in response to rainfall events. In the present study, time series models using artificial neural networks (ANNs) and support vector machines (SVMs) have been developed and applied to groundwater level data from the Gasan, Shingwang, and Cheongseong stations of the National Groundwater Monitoring Network. We designed four types of model according to input structure and compared their performances. The results show that the rainfall input model is not effective, especially for the prediction of groundwater recession behavior; however, the rainfall-groundwater input model is effective for the entire prediction stage, yielding a high model accuracy. Recursive prediction models were also effective, yielding correlation coefficients of 0.75-0.95 with observed values. The prediction errors were highest for Shingwang station, where the cross-correlation coefficient is lowest among the stations. Overall, the model performance of SVM models was slightly higher than that of ANN models for all cases. Assessment of the model parameter uncertainty of the recursive prediction models, using the ratio of errors in the validation stage to that in the calibration stage, showed that the range of the ratio is much narrower for the SVM models than for the ANN models, which implies that the SVM models are more stable and effective for the present case studies.