• Journal of the Korean Society for Precision Engineering
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• v.24 no.10
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• pp.64-74
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• 2007

Because of the size and environment in the shipbuilding process, the portable type robot is required for the automatic seam tracking. For this reason, the structure of laser sensor should be considered in the initial design step and the coordinate transformation between welding robot and laser sensor, which is joint finder, must be identified exactly and the real time tracking algorithm based on these consideration could be developed. In this research, laser displacement sensor in which its structure is laser beam's vertical projection, is developed to recognize the location of weld joint. In practical applications, however, images of weld joints are often degraded because of the surface specularity or spatter. To overcome the problem, the constrained joint finding algorithm is proposed. In the approach of coordinate conversion rule for the visual feedback control among welding torch, robot body and laser sensor is applied by the same reference point method. In the real time seam tracking algorithms we propose constrained sampling method which uses look ahead distance. The RLS(Recursive Least Square) filter is applied to obtain the smooth tracking path from the sensitive edge data. From the experimental results, we could see the possibility that the developed laser sensor with proposed processing algorithm and real time seam tracking method can be used as a welding under the shipbuilding condition.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.6
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• pp.492-501
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• 2016

Three-Loop autopilot is generally used for the acceleration control of guided missiles. Because the acceleration command to the three-loop autopilot is given as values at the center of gravity, feedback information of IMU should be obtained at the same position. However, the position of IMU might not be located at the center of gravity due to the sub-system assignment. This paper presents the stability analysis of three-loop autopilot with respect to the arbitrary position of IMU and variation rate of center of gravity. Gain and phase margins are calculated for several trim points for general anti-tank missiles.

• Journal of Korean Medical classics
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• v.13 no.1
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• pp.233-252
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• 2000

The contents of Yuk Mee Jee Dae Ron(六微旨大論) are as follows. 1. The Yuk Mee Jee Dae Ron(六微旨大論) is one of the Wun Gi Chil Pean(運氣七篇) which are inserted in So Moon(素問) by Wang Bing(王氷) who compile the So Moon(素問) into 24 volume. Wun Gi Chil Pean(運氣七篇) are Chun Won Ki Dae Ron(天元紀大論), O Woon Heng Dae Ron(五運行大論), Yuk Mee Jee Dae Ron(六微旨大論), Gi kuoo Beun Dae Ron(氣交變大論), O Sang Jeong Dae Ron(五常政大論), Yuk Won Jeong KI Dae Ron(六元正紀大論), Gee Gean Yoo Dae Ron(至眞要大論). 2. It prescribe the Sa Chun(司天) Jae Chun(在泉) Jwa Gan Gi(左間氣) Woo Gan Gi(右間氣). 3. It prescribe the Pheo Gi(標氣) Bon Gi(本氣) Juoog Gi(中氣). 4. It prescribe the Youk BO(六步) and the Sheung Gi(承氣). 5. It prescribe the Hamg Hae Sheung Jae(亢害承制) which is feedback control system between each Yuk Gi(六氣). 6. It prescribe the Sae whae(歲會), the Chun Boo(天符) and the Tae Il Chun Boo(太一天符). 7. It prescribe the active time of Yuk gi(六氣) within a year and Sae gi Whae Dong(歲氣會同). 8. It prescribe the Gi Gieo(氣交) which human beings and all the creation are living on. 9. It prescribe the Bo(步) which are composed of Chun Gi(天氣) and Jee Gi(地氣). 10. It prescribe the Duk(德) Wha(化) Yooung(用) bean(變) which are created by quarrel of Yuk Gi(六氣). 11. It prescribe the outbreak of the Sa Gi(邪氣). 12. It prescribe the Sin Gi(神機) and Gi Rib(氣立). 13. It prescribe all the creations existence are up to the Seoung Gang Chul Ip(升降出入). Like the past, the Yuk Mee Jee Dae Ron(六微旨大論) is include very important concep of the medicine. So the study should be continued with minute attention.

• The Journal of Information Technology
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• v.5 no.2
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• pp.95-106
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• 2002

This study attempts to construct and manage the distance learning system by focusing on education institutins. However, they lack not only web-based courseware for information literacy but also the contents for the management technology. This study tried to design and implement the web-based courseware by using OCP(Oracle Certified Profession) based on the initial Oracle in distance learning. Learners' individual variations were considered based on problem solving learning. Also, the practical contents that could be applied in the educational field were selected. The learning type web-based courseware, using the technology of ASP, DHTML, JAVAscript, VBA, was designed and implemented into the framework that could be updated easily. The result of the study shows: first of all, this courseware induced a greater understanding of the Oracle language and the student's interests. Secondly, the student's had more control over the process of individual learning and achieved the goal more effectively through immediate feedback, finally, the students could learn wherever they have on-line connections to the web server.

• International journal of advanced smart convergence
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• v.7 no.1
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• pp.42-47
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• 2018

Recently, as the demand for limited resources continues to rise and problems of resource depletion rise worldwide, the importance of renewable energy is gradually increasing. In order to solve these problems, various methods such as energy conservation and alternative energy development have been suggested, and biogas, which can utilize the gas produced from biomass as fuel, is also receiving attention as the next generation of innovative renewable energy. New and renewable energy using biogas is an energy production method that is expected to be possible in large scale because it can supply energy with high efficiency in compliance with energy supply method of recycling conventional resources. In order to more efficiently produce and manage these biogas, a biogas plant has emerged. In recent years, a large number of biogas plants have been installed and operated in various locations. Organic wastes corresponding to biogas production resources in a biogas plant exist in a wide variety of types, and each of the incoming raw materials is processed in different processes. Because such a process is required, the case where the biogas plant process is inefficiently operated is continuously occurring, and the economic cost consumed for the operation of the biogas production relative to the generated biogas production is further increased. In order to solve such problems, various attempts such as process analysis and feedback based on the feedstock have been continued but it is a passive method and very limited to operate a medium/large scale biogas plant. In this paper, we propose "CNN-based production yield prediction algorithm for increasing process efficiency of biogas plant" for efficient operation of biogas plant process. Based on CNN-based production yield forecasting, which is one of the deep-leaning technologies, it enables mechanical analysis of the process operation process and provides a solution for optimal process operation due to process-related accumulated data analyzed by the automated process.

• Aerospace Engineering and Technology
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• v.1 no.2
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• pp.105-112
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• 2002

In this paper, a servo filter design for the gimbal engine actuator system of KSR-III(Korea Sounding Rocket-III) is considered. A reasonable filter structure is determined based on the actuator analytic models. The servo filter consists of a 2-nd order lowpass filter and a 1-st order compensator. The lowpass filter is required to protect the actuator from high frequency vibration, and the compensator to enhance the resulting stability. A Butterworth type servo filter is considered as the simplest one. The final servo filter type is determined by evaluating simultaneously both high frequency gain reduction performance and the corresponding KSR-III stability margin. Consequently it is revealed that a notch type servo filter located on the error between command signal and feedback signal in the control loop is very effective. Later, based on the proposed servo filter type, an onboard servo filter hardware of KSR-III will be designed and tested.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.12
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• pp.2812-2817
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• 2013

In this paper, an outage probability for the best relay selection in decode-and-forward relaying systems in the presence of interference is analyzed over Rayleigh fading channels. Based on the outage performance results, we propose a method to determine effective relay candidates for the best relay selection, where the effective relay candidates represent the relays except for relays that make no contribution to improving the performance. in all possible relays given in the system. By determining the effective relay candidates, the feedback overhead of channel state information and the energy consumption of relays can be significantly reduced while minimizing the performance degradation. In this paper, we provide important parameters that affect the determination of the effective relay candidates.

• Journal of Korean language education
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• v.25 no.1
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• pp.53-82
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• 2014

This study aims to find the method to promote interaction in L2 classrooms. Active interaction between learner-to-learner and learner-to-teacher in L2 classroom plays an important role in language acquisition. In light of this, L2 classroom would benefit with the help of learning tools such as Clickers which helps learners to express their level of understanding during the process of learning itself. This is because the anonymity of Clickers allows learners to express their needs without the social risks associated with speaking up in the class. It allows for an evaluative feedback loop where both learners and teachers understand the level of progress of the learners, better enabling classrooms to adapt to the learners' needs. Eventually this tool promotes participation from learners, This is in turn, believed to be effective in fostering classroom interaction, allowing learning to take place in a more comfortable yet vibrant way. This study is finalized by presenting the result of an experiment conducted to verify the effectiveness of this approach when teaching pragmatic aspect of the Korean expressions with similar semantic functions. As a result of the research, the learning achievement of learners in the experimental group was found higher than the learners' in a control group. Analyzing the data collected from a questionnaire given to the learners, the study presented data suggesting that this approach increased the scope of interactivity in the classroom, thus enhancing more active participation among learners. This active participation in turn led to a marked improvement in their communicative abilities.

• Journal of Information Technology Services
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• v.20 no.2
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• pp.1-11
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• 2021

As a key of access to public participation and information, e-government is taking the active role of public service by relevant laws and policy measures for universal use of e-government websites. To improve the accessibility of web contents, the level of deriving the results for each detailed evaluation item according to the Korean web contents accessibility guideline is carried out, which is an important factor according to the detailed evaluation items for each website property and requires data-based management. In this paper, detailed indicators are analyzed based on the quality control level diagnosis results of existing domestic e-government websites, and the results are classified according to high and low to propose new improvement directions and induce detailed improvement. Depending on the necessity of management according to the detailed indicators for each website attribute, not only results but also level diagnosis to strengthen web service quality suggests directions for future improvement through accurate detailed analysis and research for policy feedback. This study ultimately makes it possible to expect government system management based on predicted data through deduction history management based on evaluation score data on public websites. And it provides several theoretical and practical implications through correlation and synergy. The characteristics of each score for the quality management of public sector websites were identified, and the accuracy of evaluation, the possibility of sophisticated analysis, such as analysis of characteristics of each institution, were expanded. With creating an environment for improving the quality of public websites and it is expected that the possibility of evaluation accuracy and elaborate analysis can be expanded in the e-government performance and the post-introduction stage of government website service.

• Smart Media Journal
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• v.11 no.5
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• pp.26-37
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• 2022

In this paper, images are automatically acquired to control the initial disease of strawberries among facility cultivation crops, and disease analysis is performed using the EfficientNet model to inform farmers of disease status, and disease diagnosis service is proposed by experts. It is possible to obtain an image of the strawberry growth stage and quickly receive expert feedback after transmitting the disease diagnosis analysis results to farmers applications using the learned EfficientNet model. As a data set, farmers who are actually operating facility cultivation were recruited and images were acquired using the system, and the problem of lack of data was solved by using the draft image taken with a cell phone. Experimental results show that the accuracy of EfficientNet B0 to B7 is similar, so we adopt B0 with the fastest inference speed. For performance improvement, Fine-tuning was performed using a pre-trained model with ImageNet, and rapid performance improvement was confirmed from 100 Epoch. The proposed service is expected to increase production by quickly detecting initial diseases.