• Title/Summary/Keyword: Operation obstacles

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Algorithm on Detection and Measurement for Proximity Object based on the LiDAR Sensor (LiDAR 센서기반 근접물체 탐지계측 알고리즘)

  • Jeong, Jong-teak;Choi, Jo-cheon
    • Journal of Advanced Navigation Technology
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    • v.24 no.3
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    • pp.192-197
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    • 2020
  • Recently, the technologies related to autonomous drive has studying the goal for safe operation and prevent accidents of vehicles. There is radar and camera technologies has used to detect obstacles in these autonomous vehicle research. Now a day, the method for using LiDAR sensor has considering to detect nearby objects and accurately measure the separation distance in the autonomous navigation. It is calculates the distance by recognizing the time differences between the reflected beams and it allows precise distance measurements. But it also has the disadvantage that the recognition rate of object in the atmospheric environment can be reduced. In this paper, point cloud data by triangular functions and Line Regression model are used to implement measurement algorithm, that has improved detecting objects in real time and reduce the error of measuring separation distances based on improved reliability of raw data from LiDAR sensor. It has verified that the range of object detection errors can be improved by using the Python imaging library.

Real-time monitoring of ship's dynamic behavior characteristics by AIS (AIS에 의한 선박거동의 실시간 모니터링)

  • Lee, Dae-Jae
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.44 no.3
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    • pp.218-228
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    • 2008
  • This paper describes on the real-time tracking of ship's dynamic behavior by AIS information in the coastal waters. The AIS data was received at a land station by using the antenna of AIS receiver mounted on the rooftop of the laboratory, Pukyong National University (PKNU), Busan, Korea, and stored as a NMEA format of serial output sentence of VDM(VHF Data-Link Message) and displayed on the ENC(Electronic Navigational Chart) of a PC-based ECDIS. In this study, the AIS receiver was mainly used to obtain the dynamic information that is necessary to evaluate and track the movement situation of training ship "KAYA" of PKNU in the coastal waters. The change of position with time for the ship turning under the rudder angle of port $30^{\circ}$ was correctly tracked with the turning circle of 940 m in diameter on the ENC of a PC-based ECDIS. Then, the dynamic information of the AIS system was updated every 6.29 seconds under the turning situation for the speed of 10.9 knots and every 21.65 seconds under the situation running at the speed of 11.05 knots on the straight line route of $155^{\circ}$, respectively. In case of AIS target tracking in the inshore zone behind large topographical obstructions, such as mountain and apartment buildings, the update rate of dynamic information was irregularly changed by the existence of land obstacles. However, the position tracking by AIS information under the situation existing no sea obstructions was achieved in real or near real-time and the instant presentation of course alternations for the ship was correctly monitored by using a PC-based ECDIS. From these results, we concluded that the PC-based ECDIS technology and methodology combined with the AIS information can be easily extended and applied to the surveillance and management for the fishing operation of fishing vessels in the coastal zone and in the EEZ fishing grounds.

A Study for Improving the Managerial and Technological Consultancy for Korean Medium Industries. (한국 중소기업을 위한 경영.기술 지도사업의 효율화 방안)

  • 장영기
    • Journal of the Korean Professional Engineers Association
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    • v.13 no.4
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    • pp.31-47
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    • 1980
  • Since medium and small manufacturing enterprises have , played a very important role not only in national economy but also in political and social relationships all of the countries in the world have paid favorable policies and programmes for protecting and promoting this sector. In Korea main ingredients of promoting policy for this sector consist of (1) encouragement to modernize facilities and rationalize operation (2) special priority in bank loan (3) promotion of industrial cooperatives (4) prevention of infringement by large industries. However, substantial investigation for problems incurred in medium industries has revealed that unless medium industries improve and raise their technological and managerial skillfulness for themselves all other measures are useless to solve the problems. This realization has induced all of the countries to render extension services on both of technology and management to assist and support their own effort for rationalization. Also in Korea during past 20 years many technical and managerial research institutes have rendered free consultancy services to medium industries by the support of government subsidy. Among them the joint extension services project performed by the Medium Industry Bank and UNDP during 1967 and 1975 might he listed as model case because of its broad and integrated activities and participation of foreign experts. We think many precepts should be :learned from the study of this project. Korean economy is expected to develop rapidly throughout coming'80 in spite of many obstacles, tut there is an apprehension that gap in of every facet between medium and large enterprises might he deepened and enlarged. To prevent the actualization of so-called dual structure of national economy and to promote stabilized medium industries with high added value productivity which are shown in well developed countries, consultancy assistance ana extension services should be strengthened much more than ever. Fortunately in 1978 legislation of "Medium and small industry promotion act" has paved the way for the systematic achivement of consultancy and extension services which shall be integrated by the government overall program. Under new framework thoughtfull accomplishment should be undertaken considering precious precepts obtained from past experience and failure. Special attention should be given to the technical liaison officer scheme, exclusive participation of only professional institutes, strict qualification and training for consultants for the future succsseful implementation.

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Teachers' Expectations for Reforming Primary School Library Services (초등학교도서관의 봉사 개선을 위한 교사의 기대)

  • 김병주
    • Journal of Korean Library and Information Science Society
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    • v.32 no.4
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    • pp.119-146
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    • 2001
  • The purpose of school education and that of school library services are the same and the school librarians are expected to provide useful programs for the curriculum development. The effective operation of the school library need to be reformed in spite of various obstacles. If the primary school teachers perception and expectation on school librarians'roles are appropriate this will greatly motivate and mare active utilization of school library by the students. The purpose of this study are to survey the role of school librarian and to friend out the perception and expectation of primary school teachers on the school library services and finally to use its results for more efficient management of school library in teaching programs. It is conclude, base on the results, that they recognize the importance of school library and need to assign school librarians and also expect various services including school library education programs.

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A Study on the COD Removal in the Paste-board Wastewater by Activated Sludge Process (활성오니법에 의한 판지폐수중의 COD 제거에 관한 연구)

  • 도갑수;김영운
    • Journal of the Korean Professional Engineers Association
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    • v.18 no.3
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    • pp.28-35
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    • 1985
  • As the paper industry consumes much water in process and discharge wastewater containing suspended solid and COD(chemical oxygen demand), relevant law against this discharge has been set up to limit the total containment of COD in discharge. This study has been carried out to improve the treatment method for the soluble COD in wastewater produced during the process of paste-board production, which is made of semichemical pulp and waste paper. Applicated methods are, O$_2$AS : O$_2$ activated sludge process DAS : Deep well activated sludge process SAS : standard activated sludge process and proper combination of DAS and SAS 1) As a result of this experiment, we get the following conclusion between in COD sludge loading "X" and COD removable rate in the process of treating waste-water. COD removable rate(%)=(0.778+0.0146/X)${\times}$100(%)……(7) 2) In case that the COD sludge loading is high, it has been cleared out that the COD removable rate shall become low due to unknown unsoluble substances contained in the process. Meanwhile, to increase the efficiency rate of treatment, it is thought to be necessary, to provide long-time contacts with activated sludge. 3) Once the COD of original waste-water and the target COD of treated water are decided, COD sludge loading is obtained from equation(7), and capacity of aeration tank in the effective systems such as O$_2$AS, DAS, to bet the required COD removable rate can be decided. Therefore the choice among SAS, O$_2$AS, DAS methods is made in consideration of required COD removable rate and allowable installation area. 4) In the sedimentation tank with sludge bulking, it is possible to increase the COD removable rate by 3~7% but still there exist many obstacles to manage this operation.

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Cross-Border Interactions in the Swiss - German - French Border Region (스위스.독일.프랑스 접경지역에서의 월경적(越境的) 상호작용)

  • Kim Boo-Sung
    • Journal of the Korean Geographical Society
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    • v.41 no.1 s.112
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    • pp.22-38
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    • 2006
  • This paper is to explore the cross-border interactions and the formation of trans-boundary regional identity in the Swiss-German-French border region. It begins with a brief review of recent studies on 'boundary and border region', in order to gain a insight into the theoretical debates on this theme and to find out ideal types of the cross-border co-operations. And then it deals with the everyday cross-border movements(working, shopping, living) in 'Regio TriRhena', discussing the development of the trans-boundary co-operations in the EuroRegion 'Upper Rhine'. There are several committees to be defined in trans-boundary co-operation on the 'Upper Rhine', with different scopes of action, structured collectively like Russian dolls(Babushka principle). The economic differences between 3 countries trigger massive cross-border movements. This paper attempts to organize these cross-border interactions around Ullman's 3 bases for spatial interaction(complementarity, transferability, intervening opportunity). In conclusion, this paper shows that the elimination of economic obstacles does not suffice to create trans-boundary identity or a trans-border common regional spirit.

Analysis of Dynamic Stability of Limit-cycle Navigation Method (Limit-cycle 항법의 동역학적 안정성 분석)

  • Kim, Dong-Han;Kang, Soo-Hyeok;Lee, Eun-Jin;Ko, Kuk-Won;Nam, Sang-Yep
    • 전자공학회논문지 IE
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    • v.46 no.3
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    • pp.33-41
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    • 2009
  • Because the stability of obstacle avoidance ability is important for the safe operation of mobile robots, this paper deals with the analysis of dynamic stability of Limit-cycle navigation method that was proposed by authors. Limit-cycle navigation method is fast and easy to implement for fast moving mobile robots using limit-cycle characteristics of the 2nd-order nonlinear function. It can be applied to robots in dynamically changing environment such as the robot soccer. By adjusting the radius of the motion circle and the direction of the obstacle avoidance, the mobile robot can avoid the collision with obstacles and move to the destination point. The stability of Limit-cycle navigation method is analyzed with a linear model. To demonstrate the effectiveness and applicability, it is applied to the robot soccer Simulations and real experiments ascertain the merits of the proposed method.

A Study on the Efficiency of Public Library in Present Condition and Management Analysis (공공도서관 설치 현황과 운영 분석에 대한 효율화 방안 연구)

  • Yaon, Yong-Gi;Lee, Jae-Rim
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.6 no.1
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    • pp.1-24
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    • 2007
  • Public library is established on impartial accessibility of any distinction as their sex, age, financial status, etc. The function of public library is not only to accumulate materials and offer information but also minimize gulf between the rich and the poor by knowledge possession, which is realized by important means to intercept exclusive possession and power in knowledge pose-industrial society. As it is judged that most public library is established to individual building with thousands of cost, it is judged of obstacles to Increase library buildings. The purpose of this study is try to find the way to Increase In number of public library In Seoul by interaction local education-cultural facilities. The result from this study, the user rate of public library is influenced by number of buildings and accessibility of traffic and public library can improve efficiency by substantial operation by basic function for all age group. The target population of Seoul public library sizes by decuple of advanced countries because of difficulty of accessibility, so it needs to make it small scale and also can offer self-regulation learning, materials and life-long learning programs because generally public library's utilization purpose is different by age. As school in Seoul amounts to 25 times of public library by about 1,200 buildings and can function of lifelong education center with a school library, cultural center and other composition buildings, so school facilities may use as a public library for local residents.

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Water, Energy, Cooperation, and Conflict inthe Kura-Araks Basin of the South Caucasus

  • Campana, Michael E.
    • Proceedings of the Korea Water Resources Association Conference
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    • 2011.05a
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    • pp.3-3
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    • 2011
  • After the dissolution of the Soviet Union, the Kra-Araks Basin (KAB) became an international river basin with respect to the South Caucasus states of Armenia, Azerbaijan, and Georgia. However, there are no agreements regarding water allocation, water quality, or ecosystem maintenance among the aforementioned riparians. The main water problems in the basin include not only water quantity and quality, but also the lack of joint management. The aforementioned countries share many similar circumstances: location in a politically unstable but strategic region bureaucratic and structural issues; and more importantly, ongoing ethnic and related conflicts. Despite these obstacles, the countries recognize that they depend greatly on the basin, whose waters they must share. To that end, they proposed and participated in the joint NATO-OSCE South Caucasus River Monitoring (SCRMP) project between 2002 and 2009.The SCRMP sought to investigate and characterize the surface water quality in the KAB by providing equipment and training to all three countries. Several years' worth of water quality data were collected in the KAB: major ions; heavy metals; POPs (persistent organic pollutants); and radionuclides; The North Atlantic Treaty Organization (primary funder) and the Organization for Security and Co-operation in Europesupported the SCRMP not only to build capacity but also to promote cooperation and minimize conflict over water and other resources, thus providing a measure of security for Europe and other regions. The South Caucasus is a strategically-important region, functioning as a bridge between Asia and Europe. Energy-rich Azerbaijan seeks to become a key player in trade by serving as a transportation and energy hub between the energy and mineral-rich Central Asian KUT countries (Kazakhstan, Uzbekistan, and Turkmenistan) and Western Asia, Europe, and other areas. The presentation will summarize the scientific results of the SCRMP, elucidate the regional water-energy-security nexus, discuss future work in the region, and explain why the world needs to be concerned about the KAB and the entire South Caucasus.

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Analysis of Relation between Conduction Path and Threshold Voltages of Double Gate MOSFET (이중게이트 MOSFET의 전도중심과 문턱전압의 관계 분석)

  • Jung, Hakkee;Han, Jihyung;Lee, Jongin
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2012.10a
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    • pp.818-821
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    • 2012
  • This paper have analyzed the change of threshold voltage for conduction path of double gate(DG) MOSFET. The threshold voltage roll-off among the short channel effects of DGMOSFET have become obstacles of precise device operation. The analytical solution of Poisson's equation have been used to analyze the threshold voltage, and Gaussian function been used as carrier distribution to analyze closely for experimental results. The threshold voltages for conduction path have been analyzed for device parameters such as channel length, channel thickness, gate oxide thickness and doping concentration. Since this potential model has been verified in the previous papers, we have used this model to analyze the threshold voltage. Resultly, we know the threshold voltage is greatly influenced on the change of conduction path for device parameters of DGMOSFET.

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