• Environmental and Resource Economics Review
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• v.9 no.2
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• pp.285-309
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• 2000

One of the main issues in natural resource economics is estimating the amount of stock and the biological growth functions of renewable natural resources. Since the stock level is not directly observed the usual econometric approaches cannot be employed for this purpose. The maximum entropy approach has been suggested as a useful alternative to estimate the dynamic model of natural resource use. This study estimates the stock and the growth function of Korean anchovy using the data for yield and yield efforts. The results show that the current level of anchovy yield exceeds its maximum sustainable yield, which implies that the stock will decrease substantially over time.

• Korean System Dynamics Review
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• v.10 no.2
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• pp.81-102
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• 2009

Based on various employment and technology data in the cultural sector from the mid-1990s to the mid-2000s in Seoul, Korea, this research examines whether technology- and human resource-oriented programs exert significant impact on creative manpower, R&D technology level and tolerance. After briefly introducing Seoul's trends in the culture industry, it tries to explain major reinforcing and balancing loops. The stock-flow diagram of the culture industry in Seoul is applied to estimate relative effectiveness of technology- and human resource-oriented cultural programs cultural programs. Judging from a series of simulated experiments, technology-oriented cultural programs are essential to increase creative manpower and R&D technology level in the short term. For the first half of research period, this research finds that human resource-oriented cultural programs put forth minimal impact, if they even exist at all. The trends, however, are reversed in the long term: Both size of creative manpower and R&D technology level absolutely depend on human resource-oriented cultural programs in the second half.

• 한국태양에너지학회:학술대회논문집
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• 2008.11a
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• pp.310-313
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• 2008

The wind resource potentials of South Korea are estimated as preliminary stage using the national wind map which has been being established by numerical wind simulation and GIS (Geographical Information System) exclusion analysis. The wind resource potentials are classifying into theoretical, geographical, technical and implementation potentials and the calculation results are verified by comparing to other countries' potentials. In GIS exclusion, urban, road, water body, national parks and steep slope area are excluded from onshore geographical potential while water depth and offshore distance from the shoreline are applied s offshore exclusion conditions. To estimate implementation potential, dissemination records of European countries are adopted which is about 1/8 of geographical potential.

• Journal of the Korean Solar Energy Society
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• v.28 no.6
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• pp.1-7
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• 2008

The wind resource potentials of South Korea are estimated as preliminary stage using the national wind map which has been being established by numerical wind simulation and GIS (Geographical Information System) exclusion analysis. The wind resource potentials are classifying into theoretical, geographical, technical and implementation potentials and the calculation results are verified by comparing to other countries' potentials. In GIS exclusion, urban, road, water body, national parks and steep slope area are excluded from onshore geographical potential while water depth and offshore distance from the shoreline are applied as offshore exclusion conditions. To estimate implementation potential, dissemination records of European countries are adopted which is about 1/8 of geographical potential. The implementation potential of South Korea would correspond 12.5GW which is 1.7 times of the national wind energy dissemination target until 2030.

• Journal of Communications and Networks
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• v.15 no.6
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• pp.635-644
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• 2013

Adaptive hypertext transfer protocol (HTTP) streaming has become a new trend to support adaptivity in video delivery. An HTTP streaming client needs to estimate exactly resource availability and resource demand. In this paper, we focus on the most important resource which is bandwidth. A new and general formulation for throughput estimation is presented taking into account previous values of instant throughput and round trip time. Besides, we introduce for the first time the use of bitrate estimation in HTTP streaming. The experiments show that our approach can effectively cope with drastic changes in connection throughput and video bitrate.

• IEMEK Journal of Embedded Systems and Applications
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• v.17 no.2
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• pp.93-100
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• 2022

In this paper, we propose a machine learning-based method for supporting resource management of IoT software platforms in a multi-modal sensing scenario. We assume that an IoT device installed with a oneM2M-compatible software platform is connected with various sensors such as PIR, sound, dust, ambient light, ultrasonic, accelerometer, through different embedded system interfaces such as general purpose input output (GPIO), I2C, SPI, USB. Based on a collected dataset including CPU usage and user-defined priority, a machine learning model is trained to estimate the level of nice value required to adjust according to the resource usage patterns. The proposed method is validated by comparing with a rule-based control strategy, showing its practical capability in a multi-modal sensing scenario of IoT devices.

• Environmental and Resource Economics Review
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• v.9 no.2
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• pp.333-347
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• 2000

We employed various econometic methods to estimate the production index elasticity and the price elasticity of elecricity demand in Korea and compared the forecasting power of those methods. Cointegration models (ADL model, Engle-Granger model, Full Informtion Maximum Likelihood method by Johansen and Juselius) and Dynamic OLS by Stock and Watson were considered. The forecasting power test shows that Dynamic OLS has the best forecasting power. According to Dynamic OLS, the production index elasticity and the price elasticity of electricity demand in Korea are 0.13 and -0.40, respectively.

• Environmental and Resource Economics Review
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• v.11 no.2
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• pp.279-290
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• 2002

This paper explores the impact of public financing for recycling firms on output, using a specific case study of Korea. To this end, we employ a production function approach and apply generalized method of moment estimation technique. The results show that the impact appears to be not only positive but also statistically significant, and more interestingly the estimate for financed capital is numerically larger than that for non-financed capital.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.222-229
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• 2022

Although stochastic programming and feedback control approaches could efficiently mitigate the overdue risks caused by inherent uncertainties in ground conditions, the lack of formal representations of planners' rationales for resource allocation still prevents planners from applying these approaches due to the inability to consider comprehensive resource allocation policies for hard rock tunnel projects. To overcome the limitations, the authors developed an ontology that represents the project duration estimation rationales, considering the impacts of ground conditions, excavation methods, project states, resources (i.e., given equipment fleet), and resource allocation policies (RAPs). This ontology consists of 5 main classes with 22 subclasses. It enables planners to explicitly and comprehensively represent the necessary information to rapidly and consistently estimate the excavation durations during construction. 10 rule sets (i.e., policies) are considered and categorized into two types: non-progress-related and progress-related policies. In order to provide simplified information about the remaining durations of phases for progress-related policies, the ontology also represents encoding principles. The estimation of excavation schedules is carried out based on a hypothetical example considering two types of policies. The estimation results reveal the feasibility, potential for flexibility, and comprehensiveness of the developed ontology. Further research to improve the duration estimation methodology is warranted.

• Journal of Korean Society of Forest Science
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• v.100 no.3
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• pp.455-465
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• 2011

In order to assess and mitigate climate change, the role of forest biomass as carbon sink has to be understood spatially and quantitatively. Since existing forest statistics can not provide spatial information about forest resources, it is needed to predict spatial distribution of forest biomass under an alternative scheme. This study focuses on developing an upscaling method that expands forest variables from plot to landscape scale to estimate spatially explicit aboveground biomass(AGB). For this, forest stand variables were extracted from National Forest Inventory(NFI) data and used to develop AGB regression models by tree species. Dominant/codominant height and crown density were used as explanatory variables of AGB regression models. Spatial distribution of AGB could be estimated using AGB models, forest type map and the stand height map that was developed by forest type map and height regression models. Finally, it was estimated that total amount of forest AGB in Danyang was 6,606,324 ton. This estimate was within standard error of AGB statistics calculated by sample-based estimator, which was 6,518,178 ton. This AGB upscaling method can provide the means that can easily estimate biomass in large area. But because forest type map used as base map was produced using categorical data, this method has limits to improve a precision of AGB map.