• Title/Summary/Keyword: 모아

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Dynamic Modeling based Flight Control of Hexa-Rotor Helicopter System (헥사로터형 헬리콥터의 동역학 모델기반 비행제어)

  • Han, Jae-Gyun;Jin, Taeseok
    • Journal of the Korean Institute of Intelligent Systems
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    • v.25 no.4
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    • pp.398-404
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    • 2015
  • In this paper, we describe the design and performance of a prototype multi-rotor unmaned aerial vehicle( UAV) platform featuring an inertial measurement unit(IMU) based autonomous-flying for use in bluetooth communication environments. Although there has been a fair amount of study of free-flying UAV with multi-rotors, the more recent trend has been to outfit hexarotor helicopter with gimbal to support various services. This paper introduces the hardware and software systems toward very compact and autonomous hexarotors, where they can perform search, rescue, and surveillance missions without external assistance systems like ground station computers, high-performance remote control devices or vision system. The proposed system comprises the construction of the test hexarotor platform, the implementation of an IMU, mathematical modeling and simulation in the helicopter. Furthermore, the hexarotor helicopter with implemented IMU is connected with a micro controller unit(MCU)(ARM-cortex) board. The micro-controller is able to command the rotational speed of the rotors and to get the measurements of the IMU as input signals. The control simulation and experiment on the real system are implemented in the test platform, evaluated and compared against each other.

Stream Environment Monitoring using UAV Images (RGB, Thermal Infrared) (UAV 영상(RGB, 적외 열 영상)을 활용한 하천환경 모니터링)

  • Kang, Joon-Oh;Kim, Dal-Joo;Han, Woong-Ji;Lee, Yong-Chang
    • Journal of Urban Science
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    • v.6 no.2
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    • pp.17-27
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    • 2017
  • Recently, civil complaints have increased due to water pollution and bad smell in rivers. Therefore, attention is focused on improving the river environment. The purpose of this study is to acquire RGB and thermal infrared images using UAV for sewage outlet and to monitor the status of stream pollution and the applicability UAV based images for river embankment maintenance plan was examined. The accuracy of the 3D model was examination by SfM(Structure from Motion) based images analysis on river embankment maintenance area. Especially, The wastewater discharged from the factory near the river was detected as an thermal infrared images and the flow of wastewater was monitored. As a result of the study, we could monitor the cause and flows of wastewater pollution by detecting temperature change caused by wastewater inflow using UAV images. In addition, UAV based a high precision 3D model (DTM, Digital Topographic Map, Orthophoto Mosaic) was produced to obtain precise DSM(Digital Surface Model) and vegetation cover information for river embankment maintenance.

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Factors Affecting the Reuse of Accommodation Applications and Suggestions for Improvement for it -focusing on 'yarolga' and 'goodchoice'- (숙박 애플리케이션 재이용에 영향을 끼치는 요인과 개선 방향 제안 -야놀자와 여기어때를 중심으로-)

  • Park, Jung-Hoon;Kim, Seung-In
    • Journal of Digital Convergence
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    • v.16 no.8
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    • pp.293-299
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    • 2018
  • The purpose of this study is to investigate the reasons for users to use accommodation applications and thefacts that affect reuse, and to suggest a design that can be used more conveniently for users. O2O services have diversified as more generations are enjoying leisure activities and the mobile market is expanding. Especially, the most important service in leisure activities is accommodation service. For the study, we surveyed about using accommodation application for 103 men and women in their 20s and 30s. Surveys shows that the main reason for users to reuse application is discounted services through events. Therefore, we will suggest anew design by collecting the inconveniences of users when using applications. We hope that the accommodation market can be expanded not only in Korea but also overseas markets by improving the services users, who use accommodation application, want though this study.

Rancidity Estimation of Perilla Seed Oil using NIR Spectroscopy and Multi-variate Analysis Techniques (근적외선 분광기법과 인공신경망을 이용한 식용유지의 산패 분석)

  • Lee, Ah-Yeong;Hong, Suk-Ju;Rho, Shin-Jung;Park, Heesoo;Kim, Yong-Ro;Kim, Ghiseok
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2017.04a
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    • pp.98-98
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    • 2017
  • 대부분의 가정과 요식업체, 식품가공업계에서 이용하고 있는 식용유지는 저장 및 가공과정 중에 산패가 빈번하게 일어나게 된다. 기존에는 유지 산패를 측정하기 위해 산가, 과산화물가 등을 측정하는 이화학적인 적정방법을 이용하였는데 실험자의 숙련도에 따라 결과의 오차가 발생할 수 있고, 반복실험으로 인한 시간과 비용이 많이 소모되는 등 여러 제약사항을 포함하고 있어 식용유지의 산패를 실시간 비파괴적으로 분석할 수 있는 기술의 개발에 많은 관심이 모아지고 있다. 따라서, 본 연구에서는 식용유지의 저장조건에 따른 산패정도를 비파괴적으로 평가하기 위한 근적외선 분광분석과 인공신경망 분석기술을 개발하여 그 실효성을 평가하였다. 식물성 식용유지인 들기름을 특정 온도에서 일정한 시간동안 저장하면서 이화학적 적정방법을 통해 산가와 과산화물가를 측정하였으며 동일한 시료의 근적외선 투과스펙트럼을 획득하였다. 수집된 정보를 이용하여 유지 산패 예측 모델을 개발하기 위해 다변량 분석기법 (주성분 회귀분석, 최소자승 회귀분석과 인공신경망 분석)을 적용하였다. 분석 결과, 인공신경망 분석모델이 산가 ($R^2_{tra}:0.9037$, $R^2_{val}:0.8175$, $R^2_{test}:0.8555$)와 과산화물가 ($R^2_{tra}:0.9210$, $R^2_{val}:0.9341$, $R^2_{test}:0.8286$)의 예측 성능이 가장 우수한 것으로 확인되었다. 본 연구의 결과들은 농산물과 식품의 성분 측정뿐만 아니라 다른 산업분야에서도 유용하게 활용될 수 있을 것으로 기대되어진다.

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Site Suitability Analysis for Riverbank Filtration Using Game Theory (게임이론을 활용한 강변여과 개발 적지선정)

  • Lee, Sang-Il;Lee, Sang-Sin
    • Journal of Korea Water Resources Association
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    • v.43 no.1
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    • pp.95-104
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    • 2010
  • The tap water supply in Korea mainly depends on the surface water. However, the advanced water purification process becomes a necessity due to the deterioration of surface water quality and the risk of accidental spill. High cost of water treatment and public concerns make the decision makers turn to riverbank filtration as an alternative to the surface water. Riverbank filtration has been employed for water supply in many developed countries for more than 150 years. In Korea, riverbank filtration has drawn attention since 1990s as a supply source having potential to stably meet the ever-increasing water demand. Some cities located in the Nakdong River Basin are currently supplying water through riverbank filtration. This work studies the site suitability analysis for riverbank filtration using game theory. Theory of games, which is a branch of applied mathematics used in social sciences (most notably economics), biology, engineering and computer science, was applied to candidate locations for the selection of riverbank filtration site. We proposed a policy game model as a new method adopting a probabilistic approach. The model developed turned out to be an effective tool for site selection.

Development of a Semi-automatic Cloth Inspection Machine for High-quality Fabric Patterns (고감성 패턴 제조를 위한 반자동 검단기의 개발)

  • Kim, Joo-Yong;Kim, Ki-Tai
    • Science of Emotion and Sensibility
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    • v.11 no.2
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    • pp.207-214
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    • 2008
  • The inspection processing is for reducing loss which occurs fault because of fabric appearance. Up to now inspection machine which is used from inspection process is classified with the macrography inspection machine and the full automatic inspection machine. The macrography inspection machine is low price and efficient equipment but does not record information of fault. On the other side, the automatic inspection machine is high price, also the detection rate of one changes with effect of environment variable but able to record information of fault. It developed semi-automatic cloth inspection machine with the weak point of the macrography inspection machine and the automatic inspection machine was complemented. And when it uses information which was collected by semi-automatic cloth inspection machine, the loss rate of original fabric is able to calculate. So sewing factories will be able to predict fabric consuming quantity.

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A Model for Groundwater Time-series from the Well Field of Riverbank Filtration (강변여과 취수정 주변 지하수위를 위한 시계열 모형)

  • Lee, Sang-Il;Lee, Sang-Ki;Hamm, Se-Yeong
    • Journal of Korea Water Resources Association
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    • v.42 no.8
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    • pp.673-680
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    • 2009
  • Alternatives to conventional water resources are being sought due to the scarcity and the poor quality of surface water. Riverbank filtration (RBF) is one of them and considered as a promising source of water supply in some cities. Changwon City has started RBF in 2001 and field data have been accumulated. This study is to develop a time-series model for groundwater level data collected from the pumping area of RBF. The site is Daesan-myeon, Changwon City, where groundwater level data have been measured for the last five years (Jan. 2003$\sim$Dec. 2007). Minute-based groundwater levels was averaged out to monthly data to see the long-term behavior. Time-series analysis was conducted according to the Box-Jenkins method. The resulted model turned out to be a seasonal ARIMA model, and its forecasting performance was satisfactory. We believe this study will provide a prototype for other riverbank filtration sites where the predictability of groundwater level is essential for the reliable supply of water.

The Evaluation of Regional Innovation and Cluster Policies : Theory and Methods (지역혁신과 클러스터 정책의 평가: 이론과 방법)

  • Diez, Maria Angeles
    • Journal of the Korean Academic Society of Industrial Cluster
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    • v.1 no.1
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    • pp.1-15
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    • 2007
  • Regional innovation and cluster policies are the new agenda of regional policy, an agenda that began to spread over recent years throughout different countries and regions. In this context, our main question arises: how are we going to evaluate regional innovation and cluster policies? What models and methods are we going to use? Since 1990, regional and national governments have put more emphasis on evaluation as a tool directed to produce knowledge to design better policies. The objective of this article is to summarise the main challenges arising from the evaluation of regional innovation and cluster policies and make some methodological proposals that can contribute to produce better evaluations. In the first section, there is a brief presentation of regional innovation and cluster policies, followed by a more detailed analysis, in the second section, of their principal characteristics and of the main challenges posed by their evaluation. In the third section, some evaluation proposals that can help to improve current evaluation practice are presented. The paper concludes with a short number of general recommendations that we should bear in mind when designing an evaluation of regional innovation and cluster policies.

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Study on the Trend for Changing Civil Aviation Law in Korea (국내 항공법 체계 개정 방안 - 외국의 항공법 체계와의 비교를 중심으로 -)

  • Lee, Kang-Seok
    • The Korean Journal of Air & Space Law and Policy
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    • v.19 no.2
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    • pp.55-96
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    • 2004
  • The Reform Aviation Act of 2004 that which devided the basic aviation act and the act related aviation accident investigation announced in July 2004. The purpose of this study is to review standards and recommendations of Annexes for International Civil Aviation Convention and CFR of FAA in USA, Aviation Act of Japan, Civil Aviation Act of Australia, Aeronautics Act of Canada, Air Navigation Act of Singapore. and then after these review, we tried to compare them with Korean Aviation Law, Enforcement Decree, Regulations related their system. At the result of this study, we find out many advanced countries divided into basic Aviation act and accident investigation act. finally we have suggested mid and longtern plan and implementation which applicable to set up domestic aviation law system.

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The Effect of Participation motivation of the Culture and Education Activities on the psychological well-being Convergence Formation of the Elderly (노인의 문화교육활동 참여동기가 심리적복지감의 융복합 형성에 미치는 영향)

  • Choi, Kyung-Min;Lim, Wang-Kyu
    • Journal of Digital Convergence
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    • v.13 no.6
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    • pp.55-67
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    • 2015
  • The purpose of this study is to consider the effect of the Culture and Education Activities on the psychological well-being Convergence Formation of the Elderly. This study is based on the quantitative research of 255 older adults who have participated on the Culture and Education Activities programs run by welfare center and culture center for the elderly at Seoul area. The results are as follows. First, social Goal-Oriented and Activities-Oriented have effect on Life- Satisfaction. Second, Activities-Oriented and Learning-Oriented has effect on Self-Efficacy. Third, Activities-Oriented and Learning-Oriented has effect on Participation-Attitude. Fourth, but relations of the Learning-Oriented and Life-Satisfaction, Goal-Oriented and Self-Efficacy, Goal-Oriented and Participation-Attitude were independent of each other. This study can be use to propose policies related to the elderly welfare promotion.