• Current Industrial and Technological Trends in Aerospace
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• v.7 no.1
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• pp.11-19
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• 2009

Though the regional airlines have grown consistently with world's economic recovery after 2001, now the future of them is uncertain from the current economic depression since 2007. In the regional aircraft industry, there have been two main trends that larger airplanes and regional jets inroad the market. But, the situational change including radical rise of oil price and worldwide recession induces the managerial damage of airlines and it makes them doubt about the regional jet which has been the main stream of regional aircraft after the success of the ERJ-145 in 1990s. Still, most of being developed or planed regional aircrafts choose turbo fan, the future demands of turboprop increase and it becomes a good alternative of future regional aircraft in many market forecasts. Thus in this paper, current situation and tendency of regional aircraft market are investigated with various market forecast reports.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.177-184
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• 2017

Understanding trends and drivers of technology diffusion is imperative to forecast new technology adoption and understand the process of technological innovation. Our research utilizes a quantitative trend analysis considering both technological and economic indicators for trends and drivers of technology diffusion for 32nm, 22nm, and 14nm logic semiconductor technology. In terms of technological performance, the technology diffusion curve showed an S-curve pattern during the stages of maturity and decline, and the diffusion curve showed evidence supporting the learning curve. The diffusion curve showed the life cycle duration of 2 years, and the rate of technological performance and obsolescence are observed quantitatively between generations. Architectural innovation is affected by technological drivers more significantly than economic drivers. This research has implications as empirical research on the trends and drivers of technology diffusion in the high-tech semiconductor industry, and is meaningful in forecasting new technology adoption or build technology strategy.

• Journal of the Economic Geographical Society of Korea
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• v.18 no.1
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• pp.76-86
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• 2015

In this study, we presented a method for estimating the potential population damage of the Seoul Nowon-gu area in the event of a terrorist using a vehicle improvised explosive devices (IED). Using the object-based building extraction method with orthophoto image, the area of the apartment has been determined, and the apartment's height and level were estimated based on the elevation data. Using the population estimation method based on total floor area of building, each apartment resident population was estimated, and then potential population damage at the time of terrorist attacks was estimated around the subway station through a scenario analysis. Terrorism damage using IED depends on the type of vehicle greatly because of the amount loadable explosives. Therefore, potential population damage was calculated based on the type of vehicle. In the results, the maximum potential damage population during terrorist attacks has been estimated to occur around Madeul station, Nowon-gu. The method used in this study can be used various population estimation research and disaster damage estimation.

• Journal of Korea Port Economic Association
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• v.31 no.1
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• pp.69-84
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• 2015

The purpose of this study is to forecast the seaborne trade volume during January 1994 to December 2014 using the multiplicative seasonal autoregressive integrated moving average (ARIMA) along with intervention factors and an artificial neural network (ANN) model. Diagnostic checks of the ARIMA model were conducted using the Ljung-Box Q and Jarque-Bera statistics. All types of ARIMA process satisfied the basic assumption of residuals. The ARIMA(2,1,0) $(1,0,1)_{12}$ model showed the lowest forecast error. In addition, the prediction error of the artificial neural network indicated a level of 5.9% on hidden layer 5, which suggests a relatively accurate forecasts. Furthermore, the ex-ante predicted values based on the ARIMA model and ANN model are presented. The result shows that the seaborne trade volume increases very slowly.

• The Journal of the Korea Contents Association
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• v.8 no.11
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• pp.57-64
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• 2008

The data grid computing provides geographically distributed storage resources to solve computational problems with large-scale data. Unlike cache replacement policies in virtual memory or web-caching replacement, an optimal file replacement policy for data grids is the one of the important problems by the fact that file size is very large. The traditional file replacement policies such as LRU(Least Recently Used), LCB-K(Least Cost Beneficial based on K), EBR(Economic-based cache replacement), LVCT(Least Value-based on Caching Time) have the problem that they have to predict requests or need additional resources to file replacement. To solve theses problems, this paper propose SBR-k(Sized-based replacement-k) that replaces files based on file size. The proposed policy considers file size to reduce the number of files corresponding to a requested file rather than forecasting the uncertain future for replacement. The results of the simulation show that hit ratio was similar when the cache size was small, but the proposed policy was superior to traditional policies when the cache size was large.

• Journal of Korean Society of Forest Science
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• v.104 no.4
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• pp.677-684
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• 2015

This study analyzed a long-run growth trend of the forestry sector in the Republic of Korea, and forecasted the potential growth in the future after investigating main drivers of growth in the forestry sector through growth accounting analysis. Based on results, we finally suggested a direction to go forward in order to achieve a sustainable growth in the field. After Asia financial crisis, the growth rate of the forestry sector was getting stable with the fast recovery of Korean economy. While the main drivers of growth in the field was labor and capital accumulation in 1980s and 1990s, the main driver of growth has been the increment of capital accumulation since 2000. As the result of our analysis for forecasting the potential growth in the field, the contribution of labor, capital, TFP in total growth is expected as 0.09%, 1.58%, and -0.01%, respectively. The potential growth rate of the forestry sector during 2012-2020 is predicted to be 1.65% and the total production will become 36.25 trillion won.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.8
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• pp.133-141
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• 2010

MG(Microgrid) is a small power supply system located on-site that can supply both the electricity and the hot-water simultaneously. Engineering S/W is requested to construct Microgrids economically. We developed Engineering S/W that can combine DERs (Distributed Energy Resources) most economically using the linear programming and estimate of the economic. Developed S/W was programed using GAMS(General Algebraic Modeling System) and it is composed of the optimal DER combination module and forecasting module of renewable energy's output. We embody it based on MS Excel considering the user's convenience and we show its validity through a case study. We think that developed S/W will be very useful for planning MGs and energy supply.

• Journal of Digital Convergence
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• v.18 no.7
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• pp.223-228
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• 2020

The stock price reflects people's psychology, and factors affecting the entire stock market include economic growth rate, economic rate, interest rate, trade balance, exchange rate, and currency. The domestic stock market is heavily influenced by the stock index of the United States and neighboring countries on the previous day, and the representative stock indexes are the Dow index, NASDAQ, and S & P500. Recently, research on stock price analysis using stock news has been actively conducted, and research is underway to predict the future based on past time series data through artificial intelligence-based analysis. However, even if the stock market is hit for a short period of time by the forecasting system, the market will no longer move according to the short-term strategy, and it will have to change anew. Therefore, this model monitored Samsung Electronics' stock data and news information through text mining, and presented a predictable model by showing the analyzed results.

• Journal of Korea Port Economic Association
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• v.30 no.4
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• pp.91-110
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• 2014

The Korean Government is planning to build commercial districts and amenities for the major port such as Busan, Gwangyang, and Incheon in order to activate the hinterland in each port. The foreign ports in Germany, Japan and China is competing with Korean ports are developing the commercial districts and amenities of seaport hinterland in order to support urban functions. The purpose of this study is to predict the demand for the facility of commercial districts and amenities planned in the Gwangyang seaport hinterland, then to propose its utilization plans. By the demand forecasting, the districts and amenities need to be full of office, accommodation and commercial facilities, etc. In addition, the districts need to be developed gradually for the target of 2035, considering the demand growth. Leasing out the property to secular tenants, it needs to charge rent for profits of port authority. Therefore, it is required to revise the National Ports Act for the private agency to take part in building the facilities of the commercial districts and amenities.

• Journal of Korea Port Economic Association
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• v.29 no.3
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• pp.209-232
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• 2013

Illuminating Japanese Fisharena Development Policy, we tried to find out some implications on the utilization of fishing port facilities as a way to accommodate uprising marine leisure demands of Korea. The major findings of this study are concentrated in the following three points. First, Japanese Fisharena Development Policy can be functionalized in Korea as a means of policy, but for the intervening difference of demand situation, precise forecasting on the marine leisure demands has to be preceded and Fisharena should be prepared as a supply buffer. Second, in the development stage of Fisharena, Software side is important as well as Hardware side. On the development and operation, utilizing civil organizations is necessary to bring down the wharfage of Fisharena to not suppress the marine leisure demands. Third, selection of the fishing port and decision of the development scale are additional important points. In particular, preferential consideration of utilizing inner-city fishing ports as small-scale Fisherinas to address the marine leisure demands would be desirable in Korea.