• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.620-626
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• 2004

For general nonlinear processes, it is difficult to control with a linear model-based control method and nonlinear controls are considered. Among the numerous approaches suggested, the most rigorous approach is to use dynamic optimization. Many general engineering problems like control, scheduling, planning etc. are expressed by functional optimization problem and most of them can be changed into dynamic programming (DP) problems. However the DP problems are used in just few cases because as the size of the problem grows, the dynamic programming approach is suffered from the burden of calculation which is called as 'curse of dimensionality'. In order to avoid this problem, the Neuro-Dynamic Programming (NDP) approach is proposed by Bertsekas and Tsitsiklis (1996). To get the solution of seriously nonlinear process control, the interest in NDP approach is enlarged and NDP algorithm is applied to diverse areas such as retailing, finance, inventory management, communication networks, etc. and it has been extended to chemical engineering parts. In the NDP approach, we select the optimal control input policy to minimize the value of cost which is calculated by the sum of current stage cost and future stages cost starting from the next state. The cost value is related with a weight square sum of error and input movement. During the calculation of optimal input policy, if the approximate cost function by using simulation data is utilized with Bellman iteration, the burden of calculation can be relieved and the curse of dimensionality problem of DP can be overcome. It is very important issue how to construct the cost-to-go function which has a good approximate performance. The neural network is one of the eager learning methods and it works as a global approximator to cost-to-go function. In this algorithm, the training of neural network is important and difficult part, and it gives significant effect on the performance of control. To avoid the difficulty in neural network training, the lazy learning method like k-nearest neighbor method can be exploited. The training is unnecessary for this method but requires more computation time and greater data storage. The pH neutralization process has long been taken as a representative benchmark problem of nonlin ar chemical process control due to its nonlinearity and time-varying nature. In this study, the NDP algorithm was applied to pH neutralization process. At first, the pH neutralization process control to use NDP algorithm was performed through simulations with various approximators. The global and local approximators are used for NDP calculation. After that, the verification of NDP in real system was made by pH neutralization experiment. The control results by NDP algorithm was compared with those by the PI controller which is traditionally used, in both simulations and experiments. From the comparison of results, the control by NDP algorithm showed faster and better control performance than PI controller. In addition to that, the control by NDP algorithm showed the good results when it applied to the cases with disturbances and multiple set point changes.

• Journal of Korean Society of Transportation
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• v.21 no.5
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• pp.49-58
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• 2003

The Transport policies in Korea have been planned and implemented as a part of a larger economy policy based on the achievement of economic growth. As a result, previous transport policies have been focused mostly on the supply of transport infrastructure. The average annual economic growth of six percent and a twelve percent growth in motor vehicles until the late 90s led to the acceleration of the imbalance between the supply and demand of infrastructure. As such, there is a need to establish an innovative transportation policy in order to increase national competitiveness and provide momentum for national growth in the Twenty one century. This research has developed strategies and policies based on interviews that were carried out with specialists in transport field. Moreover, some transport policies have been established for the year 2020 through the conducting of a survey. The survey was conducted by interviewing respondents on making the priority of transport policies. which was then analyzed using the Data Envelopment Analysis with ranked voting data. The results are as follows. The most urgent matter was considered to be the development of a inter-modal transport system, followed by an integrated service system for public transport, and the need to increase the competitiveness of the transport and logistics industries and to further transport safety. Meanwhile, the provision of transportation for disabled people as well as the elderly was considered to be less important in Korea than in welfare nations. This stems from the belief as further attention needs to be paid to the construction of a public transport system, the establishment of transportation networks construction in preparation for reunification and the North-East Asian era, as well as the privatization of the transport infrastructure.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.3-3
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• 2017

The question of how to establish sustainable agricultural systems has become as prominent as questions related to water, energy and climate change. High input/high output agriculture has brought with it many adverse effects; the massive deterioration of soil and water in both quantity and quality, increased greenhouse gas emissions and an increased prevalence of unsafe foods. Additionally, urbanization and climate change has worsened the shortage of farmland and reduced the supply of agricultural water. Given these challenges, maintaining, conserving and efficiently using agri-environmental resources, through fostering of sustainable agriculture, have emerged as key tasks in solving these problems. What is needed therefore is research, based on systematic and comprehensive empirical analyses, that can propose plans and methods for establishing an appropriate sustainable agricultural system. The empirical analysis of sustainable agricultural system is approached separately from economic, environmental and social aspects. An analysis of environment effect reveals that the available phosphate level is 1.3~2.1 times greater than the optimal amount in rice paddies, upland fields and orchards. Further examination has revealed that the excess nutrient is polluting both ground water and surface water. Analytical results for economic feasibility show that factors of production have been invested heavily in the rice crop. Under these conditions, sustainable agriculture, including low-input agriculture, appears to be a possible alternative that will facilitate simultaneous improvements in both economic feasibility and environment effects. Analysis results for sociality reveal that social factors include the value of producer, association and interior networks. Social conditions are comprised of leadership, consumers' awareness, education and conflict solutions. In addition, analysis as to the degree investments contribute to improving agricultural value added has revealed that the direct payment program is the most effective instrument. Experts confirm that economic feasibility can be improved by scientific and well-reasoned nutrient management on the basis of soil testing. Farmers pointed to 'economic factors' as being the largest obstacle to switching to the practice of sustainable agriculture. They also indicate 'uncertainty with regards to sustainable agriculture technology' as an impediment to practicing sustainable agriculture. Even so, farmers who believe environmental and regional issues to be the most pressing problems have expanded their practice of sustainable agriculture. The keys to establishing sustainable agriculture system are classified into the following four aspects. Firstly, from an economic aspect, the research indicates that agricultural policy needs to be integrated with environmental policy and that the function of market making based on the value chain needs to be revitalized. Secondly, from an environmental aspect, there is a need for an optimal resource management system to be established in the agricultural sector. In addition, sustainable agriculture practice will need to be extended with attendant environmentally-friendly and sustainable intensive technology also requiring further development. Thirdly, from a social aspect, green agriculture management needs to be fostered, technology and education extended, and social conflict mediated. Lastly, from a governance aspect, it will be necessary to strengthen good governance, assign and share suitable roles and responsibilities, build a cooperation system and utilize community supported agriculture.

• Journal of the Korean Society for Library and Information Science
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• v.25
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• pp.151-183
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• 1993

As many Korean libraries has begun to be automated and become a part of the worldwide, open library system, they need a new management. Therefore, the purpose of this paper is to explore the library management in automated libraries and to establish a theory of the library management in information society, The automated libraries could be well explained by the systems theory and the environment of the libraries could be well explained by the contingency theory, The following hypothesis were set to direct this research. 1. As the libraries are automated and become a part of one big, worldwide library system, the libraries interact closely with the environment so that the library and the environment become one. 2. As the libraries are automated and become a part of one big, worldwide library system, the librarians need to work in the environment for the library networks, standardization of cataloging, or government information policy making. 3. As the libraries are automated and become a part of one big, worldwide library system, the librarians only manage the library, The various other library staffs take over the traditional library services directly related to books. The data were gathered from the research done previously, Also the date were collected from the American and Japanese libraries. The findings were as follows: The environment of the library integrated all types of the library services such as school library, university library, etc. And it also integrated all the services of the media centers and the press centers, etc. to library services. And the new library services began in the environment. Librarians worked for these new services. In the library, the librarians distingushed the library system from the environment by planning : mission, goal, objectives, policy, procedures and rules. Library organization became temporary such as forming task forces or matrix or free form. The environment controlled the library. Staffs were controlled by plans or computers. And the professional librarians were controlled by their ability to solve problems raised outside the libraries. Library leaders brought in the technology to the library from its environment. The librarians led the formal and informal organizations so that the staffs cooperated well in their work. And librarians tought the library procedures to the partime workers or the temporary staffs. Participative management and management by objectives were the means of motivating staffs. Budget was based on the ever changing environment. The zero based budget method was applied. Therfore, in the information society, the professional librarians become the able managers in the library and global librarians in the environment.

• The Korean Journal of Archival Studies
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• no.14
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• pp.241-288
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• 2006

For cope with the participating government promoted local decentralization of the present time, local governments are coming to aim at the realization of local governance. Local governance refers to a way of solving public problems of urban area through partnership which is a collaboration and participation based on 'relationship' among diverse interested parties such as executive authority of policy, private sectors. First of all, it is most important task to make transparency and responsibility of all people and networks by themselves through sharing information. With like this kind of a background, local assembly is an momentos body of local governance because it is a decision making organization at the same time as a representative organization of local residents, and it has a relationship of 'check and balance' with chiefs of local governments as an organization monitoring and supervising the administration of an executive authority. Not the less, information about local assembly does not open to the public or exist. Even some informations open to the public, they are not enough to be settled distrust and low-valuation by civil society. Now Local assembly is face to a point that improve over all of record management. This study is based like this critical mind, then, it examines throughly local assembly's realities by suggestion with reforming plan of record management. Record can embody true values when record management practices indefatigably through prudential system from production until preservation. Accordingly, this study suggests management of transaction unit without the omission of record. Also this study is satisfy the condition of Korean record management system with proposals of record management policy and establishment of record center. At the conclusion of study, it puts effects into shape that local assembly secure transparency and responsibility and organize local governance by record management.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.6 no.3
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• pp.1-11
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• 2007

Seoul's transportation system was changed drastically starting the first of June in two thousand. This policy includes integrated distance-based fare system and public transportation card system called smart card. Especially, as public transportation card data contains individual travel, transfer and using modes information it is possible to catch the characteristics of path-based individuals and mass transit. Thus, public transportation card data can contribute to evaluate the mass transit service in integrated public transportation networks. In addition, public transportation card data are able to help to convert previous researches and analyses with link-based trip assignment models to path-based mass transit service analysis. In this study, an algorithm being suitable for path-based trip assignment models is suggested and proposed algorithm can also contribute to make full use of public transportation card data. For this, column generation algorithm hewn to draw the stable solution is adopted. This paper uses the methodology that is to take local approximate equilibrium from partial network and expand local approximate equilibrium to global equilibrium.

• Journal of Digital Convergence
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• v.12 no.2
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• pp.335-341
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• 2014

To play the networked video contents in a client's mobile device in real time, the contents should be delivered to it by the contents server with streaming technology. Generally, in a server-client based commerce model, the server is in charge of both the authentication of the paid customer and distribution of the contents. The drawback of it is that if the customers' requests go on growing rapidly, the service quality would be degraded results from the problems of overloaded server or restricted network bandwidth. On the contrary, in P2P based networks, more and more the demand for service increasing, the service quality is upgraded since a customer can act as a server. But, in the P2P based network, there are too many servers to manage, it's possible to distribute illegal contents because the P2P protocol cannot control distributed servers. Thus, it's not suitable for commercial purposes. In this paper, the dymanic group authentication scheme is proposed which is suited to P2P based applications. The proposed scheme consists of group based key generation, key update, signature generation and verification protocols. It can control the seeder's state whether the seeder is joining or leaving the network, and it can be applied to hybrid P2P based commerce model where sales transactions are covered by the index server and the contents are distributed by the P2P protocol.

• KDI Journal of Economic Policy
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• v.27 no.1
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• pp.211-238
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• 2005

Korea is far behind other OECD countries in economy-wise productivity: Korea's labor productivity in terms of GDP per hour worked is the lowest among OECD countries. Against the existing productivity gap, there is a worrying sign in Korea's investment trend - rapid fall in machinery and equipment investment with slow increase in R&D investment. The challenge facing Korea is how to transform her economy from catching-up model to a knowledge-based one. The paper shows that, in tandem with the structural changes that today's Korean industries are experiencing, industry's innovation system is also changing. Innovation networks are emerging as the result of economy-wise restructuring since the financial crisis of 1997 and, though still not a dominant force, the newly emerging innovation networks will be the main threads of industry's innovation activities in the future. The changes in industrial innovation system would positively contribute in raising the productivity of the Korean economy. The paper contains a case study on Korea's automobile industry in order to highlight some of main characteristics of the structural changes, in addition to a chapter that gives an overview of the evolutionary paths of the Korea's industrial innovation. The paper assesses that changes can be considered as a positive sign of future growth perspective; but there are further challenges to make the Korea's industrial innovation system effective. The list of such challenges includes strengthening upstream sectors of currently leading industries, expanding the innovation base to SME and promoting technological co-operation between domestic firms and foreign firms.

• Journal of Korean Society of Transportation
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• v.24 no.6 s.92
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• pp.89-102
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• 2006

The purpose of this paper is to develop a dynamic OD estimating model to overcome the limitation of depicting teal situations in dynamic simulation models based on static OD trip. To estimate dynamic OD matrix we used the hybrid discrete choice model(called the 'Demand Simulation Model'), which combines travel departure time with travel mode and travel path. Using this Demand Simulation Model, we deduced that the traveler chooses the departure time and mode simultaneously, and then choose his/her travel path over the given situation In this paper. we developed a hybrid simulation model by joining a demand simulation model and the supply simulation model (called LiCROSIM-P) which was Previously developed. We simulated the hybrid simulation model for dependent/independent networks which have two origins and one destination. The simulation results showed that AGtt(Average gap expected travel time and simulated travel time) did not converge, but average schedule delay gap converged to a stable state in transportation network consisted of multiple origins and destinations, multiple paths, freeways and some intersections controlled by signal. We present that the hybrid simulation model can estimate dynamic OD and analyze the effectiveness by changing the attributes or the traveler and networks. Thus, the hybrid simulation model can analyze the effectiveness that reflects changing departure times, travel modes and travel paths by demand management Policy, changing network facilities, traffic information supplies. and so on.

• Journal of Digital Convergence
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• v.14 no.2
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• pp.183-190
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• 2016

This paper proposes algorithm to reduce the computing time in a neural network that reduces transmission of data for tracking mobile objects in surveillance networks in terms of detection and communication load. Object Detection can be defined as follows : Given image sequence, which can forom a digitalized image, the goal of object detection is to determine whether or not there is any object in the image, and if present, returns its location, direction, size, and so on. But object in an given image is considerably difficult because location, size, light conditions, obstacle and so on change the overall appearance of objects, thereby making it difficult to detect them rapidly and exactly. Therefore, this paper proposes fast and exact object detection which overcomes some restrictions by using neural network. Proposed system can be object detection irrelevant to obstacle, background and pose rapidly. And neural network calculation time is decreased by reducing input vector size of neural network. Principle Component Analysis can reduce the dimension of data. In the video input in real time from a CCTV was experimented and in case of color segment, the result shows different success rate depending on camera settings. Experimental results show proposed method attains 30% higher recognition performance than the conventional method.