• Title/Summary/Keyword: Circular Points

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A Study on the Guidelines for IMO Maritime Autonomous Surface Ships(MASS) (IMO 자율운항선박 가이드라인 분석에 관한 연구)

  • Park, Han-Seon;Cha, Chong-ju;Jo, Min-chul
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2019.11a
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    • pp.137-138
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    • 2019
  • The International Maritime Organization (IMO) adopted the Circular 101 (MSC / Circ. 1604) as an interim guidelines for MASS trials at the 101st Maritime Safety Committee. This guideline will be used as a guideline for the sea trials of Maritime Autonomous Surface Ships(MASS) in the future and will be used by government authorities and stake-holders to secure infrastructure for MASS safety, environmental protection and remote operation. The purpose of this study is to analyze the Interim Guidelines for MASS Trials adopted by IMO and to clearly classify the responsibilities and obligations of governments of stake-holders, and to present the main points of risk management necessary for maritime test operation from the perspective of human factors.

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Study on Critical Impact Point for a SB2 Class Flexible Barrier (SB2등급 연성베리어의 충돌지점(CIP)에 대한 연구)

  • Heo, Yeon Hee;Kim, Yong Guk;Ko, Man Gi;Kim, Kee Dong
    • International Journal of Highway Engineering
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    • v.15 no.4
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    • pp.127-133
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    • 2013
  • PURPOSES : The impact performance of flexible barrier system such as structural response, vehicular motion and occupant safety vary depending on the impact point. Thus, to properly evaluate the performance of a flexible barrier system, impact should be made to a point which will lead to the worst possible results. This point is called the Critical Impact Point (CIP). This paper presents the way to determine the CIP for a SB2 class flexible barrier system which is consisted of Thrie-Beam rail and circular hollow tube post of 2m span. METHODS: Barrier VII simulations were made for impact points; Case 1 at a post, Case 2 at 1/3 span downstream from a post, Case 3 at middle of the span, Case 4 at 2/3 span downstream from a post. For the structural performance (deflections), impact simulation of 8000kg-65km/h-15degree was used, and for vehicle motion and occupant safety, simulation of 1300kg-80km/h-20degree impact was made and analysed. RESULTS: Case 1 gave the largest dynamic deflection of 75.72cm and also gave the largest snag value of 44.3cm. Occupant safety and exit angle of the vehicle after the impact were not sensitive to the impact point and were all below the allowable limit. CONCLUSIONS : For the SB2 class flexible barrier system's CIP can be regarded as a post which is sufficiently away from the end of Length of Need in order to avoid the end-effect of the barrier system. It can be more economic in the long run because the normal concrete pavement material is likely to cost more due to higher probability of maintenance and repair and higher social cost due to traffic accident, etc.

Fundamental Matrix Estimation and Key Frame Selection for Full 3D Reconstruction Under Circular Motion (회전 영상에서 기본 행렬 추정 및 키 프레임 선택을 이용한 전방향 3차원 영상 재구성)

  • Kim, Sang-Hoon;Seo, Yung-Ho;Kim, Tae-Eun;Choi, Jong-Soo
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.46 no.2
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    • pp.10-23
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    • 2009
  • The fundamental matrix and key frame selection are one of the most important techniques to recover full 3D reconstruction of objects from turntable sequences. This paper proposes a new algorithm that estimates a robust fundamental matrix for camera calibration from uncalibrated images taken under turn-table motion. Single axis turntable motion can be described in terms of its fixed entities. This provides new algorithms for computing the fundamental matrix. From the projective properties of the conics and fundamental matrix the Euclidean 3D coordinates of a point are obtained from geometric locus of the image points trajectories. Experimental results on real and virtual image sequences demonstrate good object reconstructions.

Vision-Based Trajectory Tracking Control System for a Quadrotor-Type UAV in Indoor Environment (실내 환경에서의 쿼드로터형 무인 비행체를 위한 비전 기반의 궤적 추종 제어 시스템)

  • Shi, Hyoseok;Park, Hyun;Kim, Heon-Hui;Park, Kwang-Hyun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39C no.1
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    • pp.47-59
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    • 2014
  • This paper deals with a vision-based trajectory tracking control system for a quadrotor-type UAV for entertainment purpose in indoor environment. In contrast to outdoor flights that emphasize the autonomy to complete special missions such as aerial photographs and reconnaissance, indoor flights for entertainment require trajectory following and hovering skills especially in precision and stability of performance. This paper proposes a trajectory tracking control system consisting of a motion generation module, a pose estimation module, and a trajectory tracking module. The motion generation module generates a sequence of motions that are specified by 3-D locations at each sampling time. In the pose estimation module, 3-D position and orientation information of a quadrotor is estimated by recognizing a circular ring pattern installed on the vehicle. The trajectory tracking module controls the 3-D position of a quadrotor in real time using the information from the motion generation module and pose estimation module. The proposed system is tested through several experiments in view of one-point, multi-points, and trajectory tracking control.

RESEARCH ON THE BAMBOO IN KOREA (Ⅷ) On the Effectiveness of Fertilizers by kind upon the New and Old Bamboos (한국산의 죽류에 관한 연구 (제8보) 신죽과 구죽에 있어서 비료의 종류에 따르는 효율성에 대하여)

  • Chong, Hyon-Pae
    • Journal of Plant Biology
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    • v.9 no.1_2
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    • pp.25-30
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    • 1966
  • The writer presented in the report 7th of this series(Chong, 1959. '62 a.b. '64, '65) the result of fertlizer application on Sasamorpha purpurascens var. borealis with regards to soil conditions, climate, planting position etc. and this report is on the effectiveness of fertilizers by kinds of the new (1-year old) and old(3-to 4 years old) Phyllostachys retticulata. The ineffectiveness of fertilizers for old bamboos aged more than 8-years old has been reported previously. The study site was chosen in a bamboo groven situated at Hyunnae Ri, Okkye Myun, Myungju Gun, Kangwon Do. Each plot was so designed that only one individual remained at the center of a circular area with a dimeter of meters by eliminating the clums and severing the rhizomes, of other individuals around it. And, for the fertilizer test, 10 individuals(the new and old: 5 to 5) were observed per kind of fertilizer used; thus marking the total number of 160 plots in all. The second part of this study was conducted for the potted individuals which numbered 48, successfully established ones out of 55 the transplanted to pots. The 48 were divided into 8 treatments: whole fertilization (NPK+compost+human manure); NPK; N; K; Human manure; compost; and the control. Amoung of fertilizers applied was 200 grams for the natural plots and 100 grams for pot; it continued for 3 years and applied twice a year (spring and summer) following the theory of Dr. Koichi-ro Ueda(1954, '60 a.b.). Measurements were taken in August each year. The resutls were confirming the fact that the bamboos require a great deal of fertilizers. The results show the following points: 1) Fertilizers were more effective in the 3 to 4 year old bamboos. 2) The order of effectiveness of fertilizers by kind was the whole fertilization, NPK, and N treatments for Phyllostachys reticulata. 3) Organic matter in addition to commercial fertilizers showed better result than the soil application of the latter due to better soil aeration.

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An Evaluation on the Cultural Sustainability of the Korean Traditional Village -The Case of Sonwon-ri Village in Youngchon- (전통마을의 문화지속성 평가 -경북 영천 선원리를 대상으로-)

  • 고석철;장병관
    • Journal of the Korean Institute of Landscape Architecture
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    • v.29 no.6
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    • pp.1-10
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    • 2002
  • The purpose of this study is to establish a model of cultural sustainability in the traditional village. Cultural sustainability is being advanced by promoting the viability of traditional arts and the unique regional features of traditional culture, such as folklore, traditional landscapes, buildings and other environments of outstanding historical value. These cultural resources were also created or occurred at specific geographic locations at certain points in time by different individuals. The content of this study was to develop a model using indicators for cultural sustainability, and to apply and evaluate the model. In older to evaluate the model, Sonwon-ri village in Yongchon, located in Kyungsangbuk-do, was selected as the case study area. The major findings are as follows: 1) Sonwon-ri village has maintained the vernacular landscape except at the entrance of village. Also, the village people have pride and have adapted to the natural environment. 2) Sonwon-ri village has a self-sustaining system and circular network within its environmental capacity. Sonwon-ri village has many historical sites and buildings such as important folk resources, cultural assets, traditional houses and pavilions. 3) The people how the theory of fens-shui which interprets the location of village in relationship to a crane mountain with the village situated as a crane head. These symbolic and cultural elements have an important role in establishing the boundary of the village. From the research it can be seen that Sonwon-ri village kept many cultural sustainability indicators in terms of active factors, physical factors and psychological factors. By analysing the participation of different scientific disciplines and identifying disciplinary categories, this study provides a basis for understanding how cultural sustainability is subjected to research in the field of landscape planning and design.

A Study on the Hangul Recognition Using Hough Transform and Subgraph Pattern (Hough Transform과 부분 그래프 패턴을 이용한 한글 인식에 관한 연구)

  • 구하성;박길철
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.3 no.1
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    • pp.185-196
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    • 1999
  • In this dissertation, a new off-line recognition system is proposed using a subgraph pattern, neural network. After thinning is applied to input characters, balance having a noise elimination function on location is performed. Then as the first step for recognition procedure, circular elements are extracted and recognized. From the subblock HT, space feature points such as endpoint, flex point, bridge point are extracted and a subgraph pattern is formed observing the relations among them. A region where vowel can exist is allocated and a candidate point of the vowel is extracted. Then, using the subgraph pattern dictionary, a vowel is recognized. A same method is applied to extract horizontal vowels and the vowel is recognized through a simple structural analysis. For verification of recognition subgraph in this paper, experiments are done with the most frequently used Myngjo font, Gothic font for printed characters and handwritten characters. In case of Gothic font, character recognition rate was 98.9%. For Myngjo font characters, the recognition rate was 98.2%. For handwritten characters, the recognition rate was 92.5%. The total recognition rate was 94.8% with mixed handwriting and printing characters for multi-font recognition.

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A Review on the Direction of the Framework Act on Resource Circulation for Establishing a Resource Circulation Society (자원순환사회 형성을 위한 "자원순환기본법"이 나아가야 할 방향)

  • Lee, Il-Seuk;Kang, Hong-Yoon
    • Resources Recycling
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    • v.25 no.6
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    • pp.82-91
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    • 2016
  • The framework act on resource circulation was got through the Korea National Assembly in May, 2016. It is the most important to analyze and understand its purpose, main contents, and policy direction of the framework act because this act will lead the resource circulation policy. Korea government is going to enact subordinate statutes such as its enforcement decree and regulation to enforce the act in January, 2018. No later than enforcement of the act, its subordinate statutes should be studied indepth and consulted without any bias in order to satisfy the intent - promotion of transition toward a resource circulation society - of the act. Therefore, in this study, the points in dispute in the act are indicated and the issues and specific directions of key articles are reviewed. The ideas to maximize the effectiveness of its subordinate statutes are also suggested.

Deformation behaviour of steel/SRPP fibre metal laminate characterised by evolution of surface strains

  • Nam, J.;Cantwell, Wesley;Das, Raj;Lowe, Adrian;Kalyanasundaram, Shankar
    • Advances in aircraft and spacecraft science
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    • v.3 no.1
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    • pp.61-75
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    • 2016
  • Climate changes brought on by human interventions have proved to be more devastating than predicted during the recent decades. Recognition of seriousness of the situation has led regulatory organisations to impose strict targets on allowable carbon dioxide emissions from automotive vehicles. As a possible solution, it has been proposed that Fibre Metal Laminate (FML) system is used to reduce the weight of future vehicles. To facilitate this investigation, FML based on steel and self-reinforced polypropylene was stamp formed into dome shapes under different blank holder forces (BHFs) at room temperature and its forming behaviour analysed. An open-die configuration was used in a hydraulic press so that a 3D photogrammetric measurement system (ARAMIS) could capture real-time surface strains. This paper presents findings on strain evolutions at different points along and at $45^{\circ}$ to fibre directions of circular FML blank, through various stages of forming. It was found initiation and rate of deformation varied with distance from the pole, that the mode of deformations range from biaxial stretching at the pole to drawing towards flange region, at decreasing magnitudes away from the pole in general. More uniform strain distribution was observed for the FML compared to that of plain steel and the most significant effects of BHF were its influence on forming depth and level of strain reached before failure.

Things unknown before being recorded (기록되기 전엔 알 수 없는 것들)

  • Lee, Kyoung Hee;Kim, Ik Han
    • The Korean Journal of Archival Studies
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    • no.68
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    • pp.107-150
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    • 2021
  • Representation of an entity starts with recognition of its existence, and recording is mutually circular in that it acts as a means to enable the recognition of the existence. No record is left on an unrecognized entity, record is distorted if any, and the distorted reproduction represents the entity, reinforcing its invisibility. Spivak describes those who cannot speak on their own and cannot be represented as subaltern. This paper examines public record, the media and research records of female restaurant workers, identifies the subaltern characteristics and limitations of their records, and suggests the points to be considered and specific roles required for recording the subalterns. If it is possible to increase the possibility of representation by completely recording a person as an entity that contains the times and society, the accountability of the record to provide an account will extend beyond institutions to the times and society, and individuals and community will be established as political subjects.