• The Transactions of the Korean Institute of Power Electronics
• /
• v.23 no.1
• /
• pp.66-71
• /
• 2018

We propose an online parameter estimation method for surface-mounted permanent-magnet synchronous motor (SPMSM) using an affine projection algorithm (APA). The proposed method estimates parameters with two APAs based on the discrete-time model equation of SPMSM during motor operation. The first APA is designed to estimate inductance, and the second APA is designed to estimate resistance and flux linkage. However, in case when the d-axis current is controlled to 0A, the second APA cannot estimate resistance and flux linkage simultaneously because the matrix rank in APA becomes deficient. To overcome this problem, we temporarily inject a negative reference current input to the d-axis control loop, and the matrix in the APA then becomes full rank, which enables the simultaneous estimation of resistance and flux linkage. The proposed method is verified by PSIM simulation and an actual experiment, and the results reveal that SPMSM parameters can be estimated online during motor operation.

• Proceeding of EDISON Challenge
• /
• 2016.03a
• /
• pp.434-442
• /
• 2016

Jansen mechanism is composed of mechanical walking linkages that are designed and optimized by Theo Jansen in 1990. Although he has made optimum values for linkage dimensions for Jansen Mechanism, there are still various applications for this mechanism and also various optimum values for each application. In this paper, Jansen Mechanism optimization has been processed for the Science Box. The Science Box has its own linkage dimensions and related components and makes space for optimization process. For the optimization 3 to 4 linkage were selected which had no similar ratios of linkages between other applied Jansen mechanisms and to reduce experiment numbers. Response Surface Method was used with Minitab 17 for optimization and m.sketch was used for experimentation. Intuitive method had to be used to find optimum values as with RSM optimum value could not be found. EDISON Designer was used to make final CAD model with optimum values and laser cutter was used to get appropriate acryl panels for legs.

• Journal of Preventive Medicine and Public Health
• /
• v.35 no.4
• /
• pp.322-330
• /
• 2002

Objective: This study was conducted to automatically improve the completeness and validity of the Daegu Cancer Registry, using cross record linkage of many data sources, and to develop a computerized patient enrollment system for efficient communication among cancer researchers via the internet. Method: We analyzed 10,229 cancer patients who were reported in the National Cancer Registry, and from pathological reports, health insurance cancer claims lists, cancer patient records at hospital information centers and death certificates from the Korea National Statistical Office. Result: We confirmed 4,624 cancer patients and found 897 of new cases from a review of medical chart. The new cases were detected efficiently using cross record linkage. We developed a computerized patient enrollment system, based on a client-sewer model, for the input of cancer patients, and then developed a web-based reporting homepage and patient enrollment system for the internet. Conclusion: This system could manage cancer databases systematically, and could be given to other researchers as a basic database.

• 대한공업교육학회지
• /
• v.33 no.2
• /
• pp.154-169
• /
• 2008

The purpose of this study was to develop learning model turtle boat of teaching-learning materials in order for the students to enhance knowledge, skill and attitude and give interest in transportation technology, and also to recognize the legacy of Korean history. The model turtle boat was developed through three major phases; preparation, development and improvement. The main results of this study were as follows: First, the model turtle boat was developed for students to cultivate design, fabrication, process abilities, and also technological literacy by experimenting and fabricating for themselves. Second, the learning model turtle boat developed is equipped with the sail using natural energy, the linkage and screw applying a mechanical energy and solar cell using solar energy among driving energy. Third, in order to increase interest and attitude regarding a ship in transportation technology, the model turtle boat was developed for students to be able to operate with wireless transceiver on water. Fourth, the model turtle boat was developed to apply the teaching and learning materials for the classes of experiment and practice in primary and secondary schools.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2015.05a
• /
• pp.220-220
• /
• 2015

Water, energy, and food security already became a risk that threatens people around the world. Increasing of resources demand, rapid urbanization, decreasing of natural resources and climate change are four major problems inducing resources' scarcity. Indeed, water, energy, and food are interconnected each other thus cannot be analyzed separately. That is, for simple example, energy needs water as source for hydropower plant, water needs energy for distribution, and food needs water and energy for production, which is defined as W-E-F nexus. Due to their complicated linkage, it needs a computer model to simulate and analyze the nexus. Development of a computer simulation model using system dynamics approach makes this linkage possible to be visualized and quantified. System dynamics can be defined as an approach to learn the feedback connections of all elements in a complex system, which mean, every element's interaction is simulated simultaneously. Present W-E-F nexus models do not calculate and simulate the element's interaction simultaneously. Existing models only calculate the amount of water and energy resources that needed to provide food, water, or energy without any interaction from the product to resources. The new proposed model tries to cope these lacks by adding the interactions, climate change effect, and government policy to optimize the best options to maintain the resources sustainability. On this first phase of development, the model is developed only to learn and analyze the interaction between elements based on scenario of fulfilling the increasing of resources demand, due to population growth. The model is developed using the Vensim, well-known system dynamics model software. The results are amount of total water, energy, and food demand and production for a certain time period and it is evaluated to determine the sustainability of resources.

• Spatial Information Research
• /
• v.9 no.2
• /
• pp.291-307
• /
• 2001

In today's environmental engineering practice, many technologies such as GIS have been adopted to analyze chemical and biological process in water bodies and pollutants movements on the land surface. However, the linkage between spatially represented land surface pollutants and the in-stream processes has been relatively weak. This lack of continuity needs to develop a method in order to link the spatially-based pollutant source characterization with the water quality modeling. The objective of this thesis was to develop a two-way(forward and backward) link between ArcView GIS software and the USEPA water quality model, WASP5. This thesis includes a literature review, the determination of the point source and non-point source loadings from WASP5 modeling, and the linkage of a GIS with WASP5 model. The GIS and model linkage includes pre-processing of the input data within a GIS to provide necessary information for running a model in the forms of external input files. The model results has been post-processed and stored in the GIS database to be reviewed in a user defined form such as a chart, or a table. The interface developed from this study would provide efficient environment to support the easier decision making form water quality management.

• Journal of Korea Technology Innovation Society
• /
• v.11 no.1
• /
• pp.91-117
• /
• 2008

The relationships between science, technology, and industry are very complicated and vary according to time. Thus, it would be almost impossible to combine the three categories in a single model. However, the linking of science, technology, and industry, which are divided according to their respective classification standards, is a starting point from which to understand how science and technology, technology and industry, and further science, technology, and industry are related to each other. Studies have been carried out to analyze the relationship between science and technology and between technology and industry, whereas no study has been undertaken to get an overall view of science, technology, and industry. Since an appropriate methodology or an analytical model has not been suggested, this paper proposes a model for generally analyzing science, technology, and industry. More specifically, this paper examines the methodology for linking science, technology, and industry. This paper uses citation analysis to analyze knowledge flow such as absorption and utilization of given knowledge, looks at the provision of knowledge to create new knowledge, and examines the use of network analysis to analyze the complicated phenomenon of knowledge flow. This paper proposes an empirical study of trend analysis of technological innovation by looking into a linkage structure of knowledge flow among science, technology, and industry based on the classification linkage and analysis methodology using scientific paper and patents.

• Journal of Digital Convergence
• /
• v.11 no.12
• /
• pp.1-10
• /
• 2013

The value added network service industry has played and important role in the telecommunication service industry and in the economic development of Korea. This study uses input-output analysis to investigate the role of value added network service sector in the Korean national economy for the period 2000, 2005, 2009, focusing on four topics in its application: production inducing effects, value-added inducing effect, employment-inducing effects by demand-driven model and supply shortage effect by supply-driven model, inflation impacts by the Leontief price model, finally analysing inter-industry linkage effects. The results of this study are as follows: production inducing effects analysis 2000 0.5253won to 2009 1.31314won, value-added inducing effects 0.25112won to 0.5337won employment inducing effects from 0.09749 to 0.21025 people grew, the supply shortage effect from 1.29003 to 2.12048won, price impact of Leontief price model was increased from 0.0022% to 0.00258%. Finally, inter-industry linkage effects, appeared to have the characteristics of final demand raw industrial.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.60 no.5
• /
• pp.29-40
• /
• 2018

Even if a small amount of arsenic (As) is entering to small agricultural reservoir from upper streams, small agricultural reservoir becomes sensitive to changes in arsenic concentration depending on the water level in case of accumulation continuously because of its scale. If we want to manage arsenic concentration in small agricultural reservoir, it is very important to understand arsenic changes in agricultural reservoir. In spite of the fact that modeling is the most accurate method for analyzing arsenic concentration changes in small agricultural reservoirs, but, it is difficult to monitor arsenic change everyday. So, if data is prepared for modeling arsenic changes, water quality modeling is more effective than monitoring. Therefore, in this study, arsenic concentration changes was simulated and arsenic concentration change mechanism in small reservoir was analyzed using hydrological and water quality monitoring data and by conducting EFDC (Environment Fluid Dynamics Code)-WASP (Water Quality Analysis Simulation Program) linkage. EFDC-WASP coupling technique was very useful for modeling arsenic changes because EFDC can consider hydrodynamic and WASP can perform arsenic concentration simulation, separately. As a results of this study, during dry season, As concentration was maintained relatively high arsenic concentrations. Therefore, water level control will be needed for managing As concentration of reservoir.

• Journal of Korea Technology Innovation Society
• /
• v.13 no.3
• /
• pp.423-445
• /
• 2010

This study purposes to suggest a next generation research and education environment which is possible by the linkage of two sectors based on cyberinfrastructure. It is to design a new research-education linkage system which can apply the results of R&D to the higher education in natural science and engineering areas. literatures were reviewed on new paradigms of R&D triggered by the advent of cyberinfrastrcuture. A couple of overseas and domestic cases of such paradigm were introduced. With the backgrounds of case studies and theoretical models, a new research-education linkage environment system was suggested. Specially e-AIRS system was introduced as an example of new model in Korea. In addition, some policy issues were discussed as related to the successful promotion of such programs.