• Journal of Power System Engineering
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• v.11 no.4
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• pp.92-97
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• 2007

This study aims at investigating the wear behavior of thermally sprayed Ni-based self-flux alloy coatings against different counterparts. Ni-based self-flux alloy powders were flame-sprayed onto a carbon steel substrate and then heat-treated at temperature of $1000^{\circ}C$. Dry sliding wear tests were performed using the sliding speeds of 0.2 and 0.8 m/s and the applied loads of 5 and 20 N. AISI 52100, $Al_2O_3$, $Si_3N_4$ and $ZrO_2$ balls were used as counterpart materials. Wear behavior of Ni-based self-flux alloy coatings against different counterparts were studied using a scanning electron microscope(SEM) and energy dispersive X-ray spectroscopy (EDX). It was revealed that wear behavior of Ni-based self-flux alloy coatings were much influenced by counterpart materials.

• Health Policy and Management
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• v.12 no.2
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• pp.92-114
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• 2002

While making a vigorous discussion about self-regulation for exponential growth of harmful health information on the Internet, many countries lave made various efforts to select and circulate high quality health information on the Internet. The purpose of this study Is to review the serf-regulation methods of health information on the Internet and to suggest quality control methods of health information on the Internet suitable for Korea. Self-regulation methods of the health information on the Internet include ‘content rating system(or content selection system)’, ‘codes of conduct or guideline’, ‘internet hot-line’, ‘education for information providers and consumers’. Any self-regulation method should be used with other methods. We can regulate health information on the Internet effectively by using both self-regulation methods and compulsive methods such as law. Also information providers, information consumers, specialists, consumer representatives, scholars, governments officers should take part in doing these efforts and make concern.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2005.05a
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• pp.401-406
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• 2005

According to the ubiquitous times that is new important topic, the miniature is demanded in the industry at large. The high accuracy and accumulation make the assembly equipment and the production equipment huge from the size of view. The huge equipment brings about the expensive price of the equipment, a low flexibleness and a low productivity. It makes the manufacturing equipment huge that the accuracy only depends on the mechanism stiffness. The position of two assembled parts is transformed with the global coordinate system whose datum is machine coordinate system. The purpose of this research is invention of the module that can adjust one part to the order part automatically. The module that has a function of self adjustment only takes a stiffness in assemble direction and can be moved freely in the other direction so this function makes a self adjustment. The self adjustment module reduces the tact time and also diminishes the inferior goods and makes reconfigurable machine in $\mu-part$ assembly.

• International Journal of Advanced Culture Technology
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• v.10 no.4
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• pp.86-93
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• 2022

To combine the science and technology creativity necessary in the era of the 4th Industrial Revolution, it is necessary to cultivate talents who can discover new knowledge and create new values by combining various knowledge with self-directed mathematical competencies. This research attempted to lay the foundation for the curriculum for fostering future creative convergence talent by preparing, executing, and reflecting on the learning plan after learners themselves understand their level and status through self-directed learning. Firstly, We would like to present a teaching-learning plan based on the essential capabilities of the future society, where the development of a curriculum based on mathematics curriculum and intelligent informatization are accelerated. Secondly, an educational design model system diagram was presented to strengthen the self-directed learning ability of mathematics subjects in the electronic engineering curriculum. Consequently, through a survey, we would like to propose the establishment of an educational system necessary for the 4th industry by analyzing learning ability through self-directed learning teaching methods of subjects related to mathematics, probability, and statistics.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.12
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• pp.1258-1268
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• 2014

In this paper, we propose and design IBFD system based on DCR. And then, we analyze effect of DC offset by self-interference in the proposed system. Also, we evaluate BER performance of the proposed system according to DC offset. As a result of the simulation, we can confirm that when the self-interference is not completely cancelled by the RF cancellation, linearity of desired signal and self-interference is distorted by DC offset. Also, in the proposed system using m-QAM modulation, DC offsets of multi-level are caused by self-interference with m-QAM modulation. As a result, constellations of desired signal and self-interference are greatly distorted. In contrast, in the proposed system using m-PSK modulation, DC offset of single level is caused by self-interference with m-PSK modulation. In this condition, we confirm that distortion of constellations of desired signal and self-interference is less than when using m-QAM modulation. That is, we can confirm that m-PSK modulation is effective than m-QAM modulation in DCR based IBFD system. Also, we can confirm that it is important to cancel self-interference as much as possible in RF-stage.

• Journal of Biosystems Engineering
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• v.24 no.3
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• pp.209-216
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• 1999

A self-travelling sprayer was developed to avoid the exposure of an operator to agricultural chemicals and exhaust gas, to improve safety and to increase working efficiency during the application and transport work in the greenhouses. This system consists of self-travelling system and the control system for application and safety device. The auto-spray car is equipped with a liquid chemical tank of 80l capacity. The travelling system adopted mechanical steering system which link mechanism of front wheel is guided by guide rollers. The sprayer travels along the guiding pipe which is set on the furrow in the greenhouses. The sprayer stops automatically applying and traveling when the liquid chemical tank becomes empty or when the sprayer reach the turning point. The spray booms swings in a vertical plane. The control system of safety devices controls the automatic stop of the sprayer when there is an obstacle on the traveling path, or when the battery becomes discharged. The auto-spray car traveled smoothly and steadily along the guide pipe during traveling straightly and turning on the ground.

• Journal of the Korea Concrete Institute
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• v.20 no.1
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• pp.109-116
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• 2008

This study was performed to get information of self-healing mechanism in cement system and the influence of waterproofing admixtures for concrete on self-healing property. For testing, cement paste specimens cured for 7, 14 and 28 days were prepared and crushed into plate-shape pieces. Screened specimens with thickness not more than 1mm were covered with wet rags and cured in a plastic container for 7 and 28 days. After stopping hydration process of the specimens by treatment with acetone, the surfaces of specimens have been contacted with wet rags were analyzed by XRD, DSC, SEM and EDX. The analysis results showed that cement paste has self-healing property and this property is mainly affected by water. Self-healing in cement system is more effective and faster at an early stage of hydration as there is enough content of unreacted cement to make an additional hydration in this period. The results of this study also showed that waterproofing admixtures for concrete have a considerable effect on self-healing of cement pastes; i.e., they improved self-healing effect of cement and, especially, the specimen using admixture C has shown a lot of needle-like or fibrous hydration products which are estimated as ettringite. It is supposed that these ettringite products are effective to enhance self-healing in cement system.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.50 no.11
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• pp.514-519
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• 2001

This Paper presents an application of a on-line self-organizing fuzzy logic controller to a boiler system of fossil-power plant. A boiler-turbine system is described as a MIMO nonlinear system in this paper. Then, three single loop fuzzy logic controllers are designed independently. The control rules and the membership functions of proposed fuzzy logic control system are generated automatically without using plant model. The simulation shows successful results for wide range operation of boiler system of fossil-power plant.

• The Journal of Fisheries Business Administration
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• v.36 no.2 s.68
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• pp.71-95
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• 2005

As one of the most popular outdoor leisure activities in the world, recreational fishing has a lof of significant meaning in terms of social, economic, and cultural views. However, both not considering an indiscreet fishing activity and environment and not thinking our next generation, fishing circumstance has been deteriorating more and more. Unlike Korea, most advanced countries enact various recreational fishing management and support policies in order to keep sustainable recreational fishing and develop eco-tourism through cooperation with government, fishing industries and civil organizations. This paper consist of the following contents. First, the study attempted to investigate how to operate management system of the recreational fishing dividing into in - land fishing and sea fishing respectively. And it exhibits issues and troubles of the realities of recreational fishing management and related fishing laws and ordinances in Korea. And then, it examines various fishing management schemes in representative advanced nations; U.S., Germany, and Japan. Also, it analyzes the advantages and disadvantages of respective recreational fishing management systems; market - based license system, qualification - based management system, and self- regulatory based management system. In addition, after these three systems are adopted to Korea's recreational fishing condition, we analyzes whether respective management systems fit or not. As a result of this, the optimal management for recreational fishing is the participatory self - management scheme in Korea. Finally, in order to support recreational fishing promotion and encouragement, issues and complementary policies with respect to recreational fishing are introduced.

• Journal of The Korea Institute of Healthcare Architecture
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• v.16 no.3
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• pp.69-79
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• 2010

Canada is a democratic country, yet it keeps a social democratic system in which the government is in charge of welfare of its people. And this is one of the most significant features about the country. Her public and private pension system has been effective since the 1920s, securing its people's fundamental income. In particular, the public medical system applies to its every citizen and performs its role. This system is called the National Medical System as well as "MEDICARE" named after its related law. However, there has been a significant change in the national medical and welfare policy due to the budget deficit. In other words, the policy was mainly implemented to welfare facilities in the past, but the policy changed to a welfare policy for the elderly with a concentration on the support for self-reliance of senior citizens since the reform. The purpose of this study is to provide data and implications for Korea through the analysis of the current situation and distinct features of the housing welfare system in Canada. This study has researched the literature on the subject with an analytic focus on three aspects that are the fundamental frame of the system, essential content (support for self-reliance and facility composition), and distinct features of the housing for the elderly. In other words, they are, first, how the fundamental frame of the housing welfare system for the elderly is composed; second, how the service for self-reliance welfare and facility service are composed; and third, what their scale and distinct spatial features of general houses for the elderly with self-reliance are. A comparative study was conducted in detail on courses and characteristics of the housing welfare system for senior citizens in Canada and the USA of North America. In particular, it reveals the scale and distinct spatial features of public houses for the elderly with self-reliance in British Columbia (BC) which is one of the main provinces of Canada.