• Journal of Biosystems Engineering
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• v.30 no.3 s.110
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• pp.185-191
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• 2005

Importance of alternative energy has been increasing due to environmental issues and lack of fossil fuels. In addition, heating cost that occupies from 30 to $40\%$ of the total production cost in the protected cultivation sector in Korea needs to be reduced for profitability and global competition. But, study on geothermal energy to solve these problems has not been activated for Korean protected cultivation. This study was conducted to develop an optimized geothermal exchange system through fundamental test of heat transfer characteristics in soil such as thermal diffusivity, changes in soil temperature during heating and cooling operations, and restorations of soil temperature after the heater was fumed off, These issues were investigated using computer simulation for different depths. The simulated characteristics were evaluated through controlled tests. Simulated characteristics of heat transfer in the soil at different depths showed a reasonable agreement with the results of the controlled tests. All of computer simulation and controlled tests, soil temperatures changed at 10cm and 20cm distance from pipe. but don't change at more than 30cm distance. It means that distances of heat transfer of the soil ranged from 20 to 30cm a day. Based on these results, the optimum spacing between adjacent heat exchange pipes and the pitch were selected as 50 and 40cm, respectively.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.395-395
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• 2000

Optimization of existing processes becomes more important than the past as environmental problems and concerns about energy savings stand out. When we can model a process mathematically, we can easily optimize it by using the model as constraints. However, modeling is very difficult for most chemical processes as they include numerous units together with their correlation and we can hardly obtain parameters. Therefore, optimization that is based on the process models is, in turn, hard to perform. Especially, f3r unknown processes, such as bioprocess or microelectronics materials process, optimization using mathematical model (first principle model) is nearly impossible, as we cannot understand the inside mechanism. Consequently, we propose a few optimization method using empirical model evolutionarily instead of mathematical model. In this method, firstly, designing experiments is executed fur removing unecessary experiments. D-optimal DOE is the most developed one among DOEs. It calculates design points so as to minimize the parameters variances of empirical model. Experiments must be performed in order to see the causation between input variables and output variables as only correlation structure can be detected in historical data. And then, using data generated by experiments, empirical model, i.e. response surface is built by PLS or MLR. Now, as process model is constructed, it is used as objective function for optimization. As the optimum point is a local one. above procedures are repeated while moving to a new experiment region fur finding the global optimum point. As a result of application to the pulp digester benchmark model, kappa number that is an indication fur impurity contents decreased to very low value, 3.0394 from 29.7091. From the result, we can see that the proposed methodology has sufficient good performance fur optimization, and is also applicable to real processes.

• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.2
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• pp.161-168
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• 2015

Recently, due to various environmental problems such as global warming, increases of international oil prices, exhaustion of resource, a paradigm of world automobile market is rapidly changing from conventional vehicles using internal combustion engine to eco-friendly vehicles using electric power such as EV, HEV, PHEV and FCEV. Generally, in order to measure fuel consumption and pollutant emissions of cars, chassis dynamometer tests are performed on various driving cycles before actual driving test. There are many driving cycles for performance evaluation of conventional vehicles. However, there is a lack of researches on driving cycle for EV. In this study, the urban driving cycle for performance evaluation of electric vehicles was developed. This study is composed of two parts. In the part 1, the urban driving cycle 'GUDC-EV(Gwacheon-city Urban Driving Cycle for Electric Vehicles)' was developed by using driving data, which were obtained through actual driving experiment, and statistic analysis with chronological table. In this paper part 2, in order to verify the developed driving cycle GUDC-EV, virtual EV platforms were configured and simulations were performed with actual driving data using In addition, simulation results were compared with existing driving cycles such as FTP-72, NEDC and Japan 10-15.

• International Journal of Railway
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• v.6 no.2
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• pp.33-44
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• 2013

In recent years, energy consumption in the transportation sector by expanding motorization continues to increase in almost every country in the world. Moreover, the growth rate of the transportation energy consumption is significantly higher than those of the civilian and industrial sectors. Therefore, every country strives to reduce its dependence on private transport, which is the main contributor to the transportation energy consumption. In many countries, concepts such as Transit Oriented Development (TOD) or New Urbanism, which controls road traffic by increasing the proportion of the public transportation significantly, have been implemented to encourage a modal shift to public transport. However, the level of change required for eliminating environmental problems is a challenging task. Minimizing transportation energy consumption by controlling the increase of the traffic demand and maintaining the level of urban mobility simultaneously is a pressing dilemma for each city. Grasping the impact of the diversity of the urban transport and infrastructure is very important to improve transportation energy efficiency. However, the potential for reducing urban transportation energy consumption has often been ineffectively demonstrated by the diversity of cities. Therefore, the accuracy of evaluating the current efficiency rate of the urban energy consumption is necessary. Nevertheless, quantitative analyses related to the efficiency of transportation energy consumption are scarce, and the research on the current condition of consumption efficiency based on international quantitative analysis is almost nonexistent. On the basis of this background problem definitions, this research first built a database of the transportation energy consumption of private modes in 119 cities, with an attempt to reflect individual travel behaviors calculated by Person Trip data. Subsequently, Data Envelopment Analysis (DEA) was used as an assessment method to evaluate the efficiency of transportation energy consumption by considering the diversity of the urban traffic features in the world cities. Finally, we clarified the current condition of consumption efficiency by attempting to propose a target values for improving transportation energy consumption.

• The Journal of Society for e-Business Studies
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• v.17 no.2
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• pp.105-114
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• 2012

Recently, global warming, energy shortage, and environmental disruption have been serious problems in every nation. It became more and more important to reduce the emission of CO2 and to use of energy efficiently. Smart grid was also introduced using the rapidly developing information technology. It deployed the mutual communication concept between customers and the suppliers in the electricity supply. There were increasing demands to adopt the smart meter and to present incentive for efficient energy usage in many developed countries. The objective of this research was to develop the optimal real time pricing model which maximized the profit of the power retailer and reduced the usage of energy. The simulation study was given to show the usefulness of the model. Simulation considered the customer demand response rate and price elasticity rate. The price elasticity rate was compared in the condition of fixed value according to time and variable value according to the customers. The optimal price model could maximize the profit of the power retailer and reduce the energy usage of the consumers.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.44 no.5
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• pp.54-63
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• 2007

The purpose of this study is to present a new energy minimization method for image completion with hierarchical approach. The goal of image completion is to fill in missing part in a possibly large region of an image so that a visually plausible outcome is obtained. An exemplar-based Markov Random Field Modeling(MRF) is proposed in this paper. This model can deal with following problems; detection of global features, flexibility on environmental changes, reduction of computational cost, and generic extension to other related domains such as image inpainting. We use the Priority Belief Propagation(Priority-BP) which is a kind of Belief propagation(BP) algorithms for the optimization of MRF. We propose the hierarchical Priority-BP that reduces the number of nodes in MRF and to apply hierarchical propagation of messages for image completion. We show that our approach which uses hierarchical Priority-BP algorithm in image completion works well on a number of examples.

• STI Policy Review
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• v.7 no.2
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• pp.106-131
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• 2016

The general purpose of this paper is to identify opportunities for and to measure existing collaboration on research and development between institutions from the countries of Asia and Latin America in FEALAC's framework, in the fields of biotechnology and nanotechnology and their convergence. The methodological approach includes scientific and technological surveillance and research seeking to identify both the R&D and innovation capacities of the countries as well as the degree of international cooperation between countries of the two regions; case studies and a study of the governance framework of international collaboration in R&D about issues considered global challenges. The study has three main findings. First, nanotechnology, biotechnology and their convergence contribute to solving the problem of contamination by heavy metals affecting most of the countries that are part of FEALAC and to address problems arising from the accelerated rate of energy consumption, which also contributes to environmental damage. In this scenario, important business opportunities arise from the adaptation and development of bio-refinery technologies. Second, the scientific relationship between FEALAC countries, mainly between Asian and Latin American countries, is weak as can be seen in research for articles and patents. But there is plenty of room and potential for improvement. Third, current and upcoming joint R&D programs and projects should be linked both to existing governance structures and to new ones that serve as experiments of STI public policy regarding innovative management of intellectual property and capacity building. Practical implications are included in lessons learned and a set of recommendations involving a couple of proposals. One proposal calls for research and innovation in promising fields for international cooperation. Another proposal creates mechanisms in the governance framework for sharing knowledge, capacity building, and funding.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.6
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• pp.67-74
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• 2013

IGCC(Integrated Gasification Combined Cycle) system is candidates which can solve the environmental problems including global warming, since it can be easily combined with CCS(Carbon Capture System). In this research, combustion instability characteristics were studied at various fuel which are composed of $H_2/CH_4/CO$ mixture. Mode analysis for instabilities observed experimentally was conducted and the linearly increasing tendency of frequency was observed as the hydrogen content in fuel increases.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.7
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• pp.117-126
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• 2014

Recently, due to various environmental problems such as global warming, increasing of international oil prices and exhaustion of resource, a paradigm of world automobile market is rapidly changing from vehicles using internal combustion engine to eco-friendly vehicles using electric power such as EV (Electric Vehicle), HEV (Hybrid Electric Vehicle), PHEV (Plug-in Hybrid electric Vehicle) and FCEV (Fuel Cell Electric Vehicle). There are many driving cycles for performance evaluation of conventional vehicles. However there is a lack of researches on driving cycle for EV. This study is composed of part 1 and part 2. In this paper part 1, in order to develop urban driving cycle for performance evaluation of electric vehicles, Gwacheon-city patrol route of police patrol car was selected. Actual driving test was performed using EV. The driving data such as velocity, time, GPS information etc. were recorded. GUDC-EV (Gwacheon-city Urban Driving Cycle for Electric Vehicles) including road gradient was developed through the results of analyzing recorded data. Reliability of the driving cycle development method was substantiated through comparison of electricity performance. In the second part of this study, the developed driving cycle was compared to simulation result of the existing urban driving cycle. Verification of the developed driving cycle for EV performance evaluation was described.

• Journal of Plant Biotechnology
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• v.37 no.4
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• pp.442-455
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• 2010

Plant factory is the fruit of the most advanced modern agricultural technology. This is a crop-producing technology that controls systematically sowing, cultivating, and harvesting crops within an indoor factory. Growing crops in a factory has advantages over traditional farming because it produces safer crops all year around due to clean environment and it is easier to hire workers at the factory. Developed countries has invested actively in this field for several decades because its economical and industrial impact are predicted to be enormous. Recently, Korea also begins to investigate this field actively to develop a system that may be competitive at global market, using technologies and human resources that Korea already has. The plant factory technology is currently less competitive than traditional farming because it requires a large initial investment and management cost and lacks cultivation technologies for various crops. However, I believe in solving these problems if plant biotechnologists participate in developing the plant factory system. If this technology is developed well in Korea, then it will play a great role in solving food and environmental issues.