• Title/Summary/Keyword: navigation studies

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Conceptual Design of Rover's Mobility System for Ground-Based Model (지상시험모델 로버 주행장치 개념 설계)

  • Kim, Youn-Kyu;Kim, Hae-Dong;Lee, Joo-Hee;Sim, Eun-Sup;Jeon, Sang-Won
    • Journal of Astronomy and Space Sciences
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    • v.26 no.4
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    • pp.677-692
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    • 2009
  • In recent years, lots of studies on the planetary rover systems have been performed around space advanced agencies such as NASA, ESA, JAXA, etc. Among the various technologies for the planetary rover system, the mobility system, navigation algorithm, and scientific payload have been focused particularly. In this paper, the conceptual design for a ground-based model of planetary rover's mobility system to evaluate mobility and moving stability on ground is presented. The status of overseas research and development of the planetary rover systems is also addressed in terms of technical issues. And then, the requirements of the planetary rover's mobility system are derived by means of considering mobility and stability. The designed rover's mobility system has an active suspension with 6 legs that controls 6 joints on the each leg in order to achieve high stability and mobility. This kind of mobility system has already applied to the ATHELE of NASA for various purposes such as transportation and habitation for human lunar exploration activities in the near future (i.e., Constellation program). However, the proposed system has been designed by focusing on the small-sized unmanned explorations, which may be applied for the future Korea Lunar exploration missions. Therefore, we expect that this study will be an useful reference and experience in order to develop the planetary exploration rover system in Korea.

Integrated Approaches to Berth Productivity Improvements in Port Development and Operation and Logistics : A Conceptual Perspective (항만개발.운영과 로지스틱스에 있어서 부두생산성 향상에 대한 종합적 접근법 : 개념적 관점)

    • Journal of Korean Port Research
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    • v.11 no.1
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    • pp.85-99
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    • 1997
  • The improvements of berth productivity is closely related to berth/port systems and its relationship extends to the overall pattern of port development/logistics, transport and trade. Since ports in general and berths in specific function as a bridge transferring seaborne cargoes from seaside to landside and vice versa, berth productivity improvements should be considered in terms of the total system in which the cargoes are transported from origin to destination via berths/ports. In that respect, the objective of this study is to improve berth productivity which is a vital factor in the strategic planning in port development and operation and logistics. According to a literature survey on the subject, the contents of the studies have been limited to either a macro-perspective or a micro-perspective which is only a partial solution to the problem. Hence, this limitation requires an integrated approach to find and ultimate solution, which should be considered not separately, but as a whole. The contents and scope of this study cover the improvements of berth productivity in conjunction with strategic planning in port development. efficient operation and logistics from two different viewpoints, macro- and micro-perspective. After that, a combination of these two perspectives is applied to the integrated approach due to lacking a comprehensive perspective from either macro-approach or micro-approach. In reality, a port itself is a complex and dynamic organization. Therefore, a comprehensive insight needs an integrated approach for the long-term national economic development. In this approach, the utmost importance is how to find the bottlenecks and to solve the problems effectively from the beginning stage in port development. In conclusion, derived from the macro- and micro-perspective. the attempt to establish an integrated approach is the merit of this study, which is required as a comprehensive measure since none of the two can be a solution independently. In terms of reinforcing this study, it needs further empirical research due to the restriction of the theoretical method of this paper. Consequently, the reinforced research will be able to enhance the integrated approach on the basis of the conceptual perspective.

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Effects of Light Pollution and Environmental Factors on Dawn Song Initiation Time of Great Tit, Parus major (빛공해 및 환경요인에 의한 박새의 새벽 Song 시작시간 영향 연구)

  • Ki, Kyong-Seok;Cho, Woo
    • Korean Journal of Environment and Ecology
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    • v.28 no.4
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    • pp.411-418
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    • 2014
  • This study seeks to identify the effects of light pollution and environmental factors on Great Tits(Parus major) bird's chirping at dawn. For this research, the campus of Sanji University, Wonju, South Korea was selected as the area with light pollution and the western forest of the Chiaksan National Park was chosen as the natural area herein. The Recording period was between March 26th and May 30th, 2014. As a result of analyzing the chirping time according to light pollution, it was found that the light pollution area clearly showed earlier chirping time than the natural area (p<0.05). Great Tits(P. major) normally start their first chirping before sunrise and in most of the days under investigation of this research, those in Sanji University started to chirp earlier. This faster chirping time seems to improve the chance for the female birds to mate with immature males thus, baby birds hatch earlier than the appropriate breeding season and results in the lack of feed resources. The correlation between Great Tits'(P. major) dawn chirping and environmental factors were investigated herein including the time of sunrise, civil twilight, navigation twilight, astronomical twilight, average temperature, highest temperature, lowest temperature, time of moonrise and cloudiness. The first chirping time of wild birds in the day was found to have correlations with all of the environmental factors excluding the time of moonrise and cloudiness. Great Tits(P. major) started their first chirping before sunrise when the day started to break around civil twilight. Along with the earlier sunrise and higher air temperature, their dawn chirping time was also quickened. The time of moonrise and cloudiness did not show a correlation and further follow-up studies will be necessary in this regard.

Feasibility Study of Case-Finding for Breast Cancer by Community Health Workers in Rural Bangladesh

  • Chowdhury, Touhidul Imran;Love, Richard Reed;Chowdhury, Mohammad Touhidul Imran;Artif, Abu Saeem;Ahsan, Hasib;Mamun, Anwarul;Khanam, Tahmina;Woods, James;Salim, Reza
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.17
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    • pp.7853-7857
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    • 2015
  • Background: Mortality from breast cancer is high in low- and middle-income countries, in part because most patients have advanced stage disease when first diagnosed. Case-finding may be one approach to changing this situation. Materials and Methods: We conducted a pilot study to explore the feasibility of population-based case finding for breast cancer by community health workers (CHWs) using different data collection methods and approaches to management of women found to have breast abnormalities. After training 8 CHWs in breast problem recognition, manual paper data collection and operation of a cell-phone software platform for reporting demographic, history and physical finding information, these CHWs visited 3150 women >age 18 and over they could find-- from 2356 households in 8 villages in rural Bangladesh. By 4 random assignments of villages, data were collected manually (Group 1), or with the cell-phone program alone (Group 2) or with management algorithms (Groups 3 and 4), and women adjudged to have a serious breast problem were shown a motivational video (Group 3), or navigated/accompanied to a breast problem center for evaluation (Group 4). Results: Only three visited women refused evaluation. The manual data acquisition group (1) had missing data in 80% of cases, and took an average of 5 minutes longer to acquire, versus no missing data in the cell phone-reporting groups (2,3 and 4). One woman was identified with stage III breast cancer, and was appropriately treated. Conclusions: Among very poor rural Bangladeshi women, there was very limited reluctance to undergo breast evaluation. The estimated rarity of clinical breast cancer is supported by these population-based findings. The feasibility and efficient use of mobile technology in this setting is supported. Successor studies may most appropriately be trials focusing on improving the suggested benefits of motivation and navigation, on increasing the numbers of cases found, and on stage of disease at diagnosis as the primary endpoint.

An Exploration of the Direction of Development of the Integrated Curriculum for Gifted: The Applicability of the Drake Model (영재를 위한 통합교육과정 개발의 방향: Drake 모형의 적용 가능성 탐색)

  • Lee, Kyungjin;Roh, IlSoon
    • Journal of Gifted/Talented Education
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    • v.24 no.2
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    • pp.217-241
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    • 2014
  • This study aimed to explore the direction and possibility of development of the integrated curriculum for the Gifted students in the discipline-centered curriculum perspective. To this end, the study analysed the Ontario interdisciplinary curriculum based on a Drake's Integration Model which is typical model of the discipline-centered curriculum and explored the applicability to Science Gifted Academy in Korea. Through showing the possibility of enrichment on the selected majors, integration with other disciplines and solving the future problems by the integrated curriculum centered on 'Big Idea', the Ontario interdisciplinary curriculum gave suggestions of curriculum integration within or through individual research and integrated curriculum for the Gifted. The application of the Ontario's "Introduction to Information studies" to "Information Science" in Science Gifted Academy in Korea could be obtained the conclusion that the Drake's Integration model is applied to the Gifted by the individualization of the navigation network, KDB(Knowledge-Do-Be) umbrella, and the final interdisciplinary task. From this result, we could suggest that the development of integrated curriculum for the Gifted should be considered the clarity of learning objectives for the Gifted, the plan of evaluation to demonstrate big understanding and big idea, the integration with other disciplines or real-world problem, as well as the need of teachers council for the integrated curriculum. This study is expected to be contribute to development of the integrated curriculum model for the gifted based on the their characteristics and to be utilized in Science Gifted Academy.

A Study on Advanced Seafarers' Training for Improving Abilities of Officers in Charge of a Navigational Watch who Handle Navigational Equipment: To Focus on the ECDIS (항해사의 항해기기 취급 능력 향상을 위한 해기 교육 개선에 대한 연구: ECDIS를 중심으로)

  • LEE, Bo-Kyeong;KIM, Dae-Hae;LEE, Sang-Do;CHO, Ik-Soon
    • Journal of Fisheries and Marine Sciences Education
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    • v.28 no.2
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    • pp.323-335
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    • 2016
  • The main reason of marine casualties is the human error in respect of ship's operation. The human error of officers in charge of a navigational watch is related to their abilities to handle of navigational equipment. Navigational devices play a key role to help officers decide what to do for safe navigation. Thus, the abilities to handle of navigational equipment mean not only operation of devices but also entire understanding of the system such as interpretation of information obtained from devices, appropriate use of information considering navigational circumstance. Qualification of seafarers is in accordance with STCW and detailed training courses for their qualification are provided by IMO model course series. Recently, ships engaged on international voyages shall be fitted with an ECDIS not later than the first survey on or after 1 July 2018. As increasing use of ECDIS on ships, marine casualties related to ECDIS are on the rise. The primary causes of the accidents are lacking understanding of ECDIS system, wrong presentation of information on display, wrong safety setting by seafarers who use ECDIS, using small-scale chart and missing charts update. As a result of these primary causes, some problems like wrong route planning and use of limited or omitted information occur. It could be happening by inappropriate seafarers' training which is not sufficient to support improving abilities of officers to handle navigational equipment. For efficient training, it is need to develop training courses. Applying full mission simulation system to seafarers' training courses with case studies and best practices which are well-constructed scenarios based on true marine casualties can increase the effect of training. To use the simulation system, it is possible that seafarers are trained under condition that closely resemble real situation. It should be considered that IMO model course be revised depending on the level of seafarers also. It could be helpful for increasing seafarers' abilities of equipment operation in place of accumulation of experience spending much time. In the short term, effort of training courses improvement for seafarers is needed and long term, it should be tried to provide stable system and services relate to ECDIS.

A Moving Object Query Process System for Mobile Recommendation Service (모바일 추천 서비스를 위한 이동 객체 질의 처리 시스템)

  • Park, Jeong-Seok;Shin, Moon-Sun;Ryu, Keun-Ho;Jung, Young-Jin
    • The KIPS Transactions:PartD
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    • v.14D no.7
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    • pp.707-718
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    • 2007
  • Recently, much studies for providing mobile users with suitable and useful content services, LBS(Location Based Service) corresponding to the change of users' location, are actively going on. First and foremost, this is basically owing to the progress of location management technologies such as GPS, mobile communication technology and the spread of personal devices like PDA and the cellular phones. Besides, the research scope of LBS has been changed from vehicle tracking and navigation services to intelligent and personalized services considering the changing information of conditions or environment where the users' are located. For example, it inputs the information such as heavy traffic, pollution, and accidents. The query languages which effectively search the stored vehicle and environment information have been studied depending on the increase of the information utilization. However, most of existing moving object query languages are not enough to provide a recommendation service for a user, because they can not be tested and evaluated in real world and did not consider changed environment information. In order to retrieve not only a vehicle location and environment condition but also use them, we suggest a moving object query language for recommendation service and implement a moving object query process system for supporting a query language. It can process a nearest neighbor query for recommendation service which considers various attributes such as a vehicle's location and direction, environment information. It can be applied to location based service application which utilizes the recommended factors based on environmental conditions.

The Design and Implementation of the System for Processing Well-Formed XML Document on the Client-side (클라이언트 상의 Well-Formed XML 문서 처리 시스템의 설계 및 구현)

  • Song, Jong-Chul;Moon, Byung-Joo;Hong, Gi-Chai;Cheong, Hyun-Soo;Kim, Gyu-Tae;Lee, Soo-Youn
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.10
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    • pp.3236-3246
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    • 2000
  • XML is a meta-language as SGML and also can be xonsructed as an Internet versionof simplified SGML being used in confunction with XLL. Xpointer and XSL. Also W3C established DTDless Well-Formed XML document to use XML document on the Web. But it isnt offered system that consists of browsing, link and DTD generating facihty, and efficiently processes DTDless Well-Formed XML document. This paper studies on an implementation and design of system to process DTDless Well-Formed XML document on the client-side. This system consists of Well-Formed XML viewer displaying Well-Formed XML documet, XLL Processor processing Xll and Auto DTD generator constructing automatically DTDs based on multiple documents of the same class. This study focuses on automatic DTD generation during hyperlink navigation and an implementation of extended links based on XLL and Xpointer. ID and Xpointer location address are used as the address mode in the links. As a result of implement of this system, it conforms to validationof extended link facihties, extracts DTD from Well-Fromed XML Documents including same root element at the same class and constructs generalized DTD.

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On the Evaluation of Physical Distribution Service in Ports (항만물류서비스의 평가에 관하여)

    • Journal of Korean Port Research
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    • v.10 no.2
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    • pp.17-29
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    • 1996
  • It is required to consider pricing and non-pricing factors and external economy in order to achieve the objects of physical distribution system in a port. Recently, among the three factors, much attention has been paid to non-pricing factor in the system. Although physical distribution service in a port(PDSP)has been frequently mentioned in documents and literature related to port and shipping studies, few study on it has not been systematically and scientifically made due to the following problems; $\circ$ there are not proper criteria to evaluate level and quality of PDSP and as a result it is difficult to set up a unified standard for doing so. $\circ$ algorithms to evaluate problems with complex and ambiguous attributes and multiple levels in PDSP are not available. This thesis aims to establish a paradigm to evaluate PDSP and to abvance existing decision making methods to deal with complex and ambiguous problems in PDSP. To tackle the first purpose, extensive and thorough literature survey was carried out on general physical distribution service, which is a corner stone to handle PDSp. In addition, through interviews and questionnaire to the expert, it have extracted 82 factors of physical distribution service in a port. They have been classified into 6 groups by KJ method and each group defined by the expert's advice as follows; a. Potentiality b. Exactness c. safety d. Speediness e. Convenience f. Linkage Prior to the service evaluation, many kinds of its attributes must be identified on the basis of rational decision owing to complexity and ambiguity inherent in PDSP. An analytical hierarchy process (AHP) is a method to evaluate them but it is not applicable to PDSP that have property of non-additivity and overlapped attributes. Therefore, probablility measure can not be used to evaluate PDSP but fuzzy measure is required. Hierarchical fuzzy integral method, which is merged AHP with fuzzy measure, is also not effective method to evaluate attributes because it has vary complicated way to calculate fuzzy measure identification coefficient of attributes. A new evaluation algorithm has been introduced to solve problems with multi-attribute and multi-level hierarchy, which is called hierarchy fuzzy process(HFP).Analysis on ambiguous aspects of PDSP under study which is not easy to be defined is prerequisite to evaluate it. HFP is different from algorithm existed in that it clarified the relationship between fuzzy measure and probability measure adopted in AHP and that it directly calculates the family of fuzzy measure from overlapping coefficient and probability measure to treat and evaluate ambiguous and complex aspects of PDSP. A new evaluation algorithm HFP was applied to evaluate level of physical distribution service in the biggest twenty container port in the world. The ranks of the ports are as follows; 1. Rotterdam Port, 2. Hamburg Port, 3. Singapore Port, 4. Seattle Port, 5. Yokohama Port, 6. Long beach Port, 7. Oakland Port, 8. Tokyo Port, 9. Hongkong Port, 10. Kobe Port, 11. Los Angeles Port, 12. New york Port, 13. Antwerp Port, 14. Felixstowe Port, 15. Bremerhaven Port, 16. Le'Havre Port, 17. Kaoshung Port, 18. Killung Port, 19. Bangkok Port, 20. Pusan Port

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A Study on the Analysis of Non-competitive factors of Mokpo port and Improvement (목포항 비경쟁 요인 분석 및 개선방안 연구)

  • Park, Gyei-Kark;Choi, Kyoung-Hoon;Lee, Cheong-Hwan
    • Journal of Korea Port Economic Association
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    • v.34 no.3
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    • pp.113-132
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    • 2018
  • Mokpo port marked the $131^{st}$ anniversary of its opening in 2018. while the Mokpo has taken the new port development initiatives, it is limited by inefficient port functioning due to the lack of maritime port policy and government investment. Hence, port logistics has not been activated. Additionally, studies on Mokpo port have not been conducted, and knowledge available on the port is declarative in nature. On the other hand, research on port competitiveness focuses on how to analyze the factors that determine port competitiveness. Therefore, this study was intended to expand the existing research on Mokpo port and conduct an analysis of non-competitiveness factors and suggested improvements by considering the operational aspect of Mokpo port. In this regard the importance of non-competitiveness factors was assessed through an analytic hierarchy process(AHP) analysis and the influence of the non-competitiveness factors was analyzed through an fuzzy structural modeling(FSM) analysis. The result of the AHP analysis show ed the important non-competitiveness factors included the deactivation of industrial complexes around Mokpo port, the number of liner route, the cost of the pilot and tug. Accor ding to the FSM analysis, the top level included the non-competitive factors at Mokpo port; the intermediate level included the number of liner routes, cost of pilot and tug, enrance and clearance fee, costs of inland transportation, fee for port facilities, and loading and unloading costs; and the bottom level comprised the most non-competitive factors including the deactivation of industrial complexes around Mokpo port, hinterland connectivity, access to international port, incentives, and cost of transportation and storage. Based on the results of analysis, improvements were suggested for non-competitive factors of Mokpo.