• Title/Summary/Keyword: 대형요소

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Structural Safety Evaluation of Cable Stayed Bridge based on Cable Damage Scenarios (사장교 케이블 손상 사나리오에 따른 구조 안전 수준 평가)

  • Kim, Ga Young;Seo, Dong-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.7
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    • pp.105-111
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    • 2018
  • This study aims to evaluate the safety for cable stayed bridge due to damages on the cable system. Many cable supported bridges, including cable stayed bridge and suspension bridge, have been built in the Korean peninsula. This requires efficient maintenance and management since this structure has complex structural components and system. This large structure also often faces risks either from manmade or natural phenomenon. In 2015 one cable-stayed bridge in South Korea had been struck by a bolt of lightning on the cables. This event had led to fire on cables. These cables had been damaged and putting the bridge at risk. This bridge was back in used after a few weeks of investigations and replacements of the cables. However, enormous social and economic expense were paid for recovery. After this event risk based management for infra structures is required by public demands. Therefore, this study was initiated and aimed to evaluate risks on the cable system due to potential damages. In this paper one cable-stayed bridge in South Korea was selected and investigated its safety based on the damage scenarios of cable system for efficient and prompt management, and for supporting decision making. FEM analysis was conducted to evaluate the safety of the bridges due to damages on the cable system.

Development for the Azimuth Measurement Algorithm using Multi Sensor Fusion Method (멀티센서 퓨전 기법을 활용한 방위 측정 알고리즘의 설계)

  • Kim, Tae-Yeong;Kim, Young-Chul;Song, Moon-Kyou;Chong, Kil-To
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.2
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    • pp.865-871
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    • 2011
  • Presently, the location and direction information are certainly needed for the autonomous vehicle of the ship. Among them, the direction information is a essential elements to automatic steering system. And the gyro-compass, the magnetic-compass and the GPS compass are the sensor indicating the direction. The gyro-compasses are mainly used in the large-sized ship of the GMDSS(Global Maritime Distress & Safety System). The precision and the reliability of the gyro-compasses are excellent but big volume and high price are disadvantage. The magnetic-compass has relatively fine precision and inexpensive price. However, the disadvantage is in the influence by the magnetism object including the steel structure of a ship, and etc. In the case of the GPS compass, the true north is indicated according to the change of the location information but in case of the minimum number of satellites or stopping of a ship or exercise in the error range, the exact direction cannot be obtained. In this paper, the performance of the GPS compass was improved by using the least-square curve fitting method for the mutual trade off of the angle sensor. The algorithm which improves the precision of an azimuth by applying the weighted value according to the size of covariance error was proposed with GPS-compass and magnetic compass. The characteristic and the performance of the proposed algorithm were analyzed and verified through experimentation. The applicability of the proposed algorithm was shown through the experimental result.

Proposing the Method for Improving the Forecast Accuracy of Loan Underwriting (대출심사의 예측 정확도 향상을 위한 방법 제안)

  • Yang, Yu-Young;Park, Sang-Sung;Shin, Young-Geun;Jang, Dong-Sik
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.4
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    • pp.1419-1429
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    • 2010
  • Industry structure and environment of the domestic bank have been changed by an influx of large foreign-banks and advanced financial products when the currency crisis erupted in Korea. In a competitive environment, accurate forecasts of changes and tendencies are essential for the survival and development. Forecast of whether to approve loan applications for customer or not is an important matter because that is related to profit generation and risk management on the bank. Therefore, this paper proposes the method to improve forecast accuracy of loan underwriting. Processes in experiments are as follows. First, we select the predictor variables which affect significantly to the result of loan underwriting by correlation analysis and feature selection technique, and then cluster the customers by the 2-Step clustering technique based on selected variables. Second, we find the most accurate forecasting model for each clustering by applying LR, NN and SVM. Finally, we compare the forecasting accuracy of the proposed method with the forecasting accuracy of existing application way.

A study on development strategy of Automated Container Terminal (자동화 컨테이너터미널 개발 전략에 관한 연구)

  • 최형림;박남규;박병주;유동호;권해경
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2004.04a
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    • pp.479-485
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    • 2004
  • The interest of ACT (Automated Container Terminal) is increasing because of expansion of container's transportation quantity, appearance of large-sized and. high-speed vessel, high labor cost of container terminal and the change of technical level. Therefore, the ACT had been developed in several ports in the world, such as ECT (Europe Combined Terminals) and CTA (Container Terminal Altenwerder). They have studied detailed technique for the operation of ACT. In Korea, it also has increased not only expansion and improvement of container terminal, but also necessity of ACT. Now, many projects related to the development of ACT are working in Korea. And the technical improvement of operating system, automated equipments and information system has accomplished by the projects. The ACT consists of the basic equipment and the integrated information system for operating and controlling automated equipments. The productivity of ACT is maximized through efficient connection between them. Thus, the automated degree of container terminal is dependent on the developing time of operating system, reliability, transportation quantity of container, investment amount and technical level. In this paper, we propose important strategy in developing ACT through analyzing the property of each ACT.

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A Study on the Improving Fiscal Capability of Local Government -Focusing on the case of zeroing debt policy in Yong-in city (지방정부 재정역량 제고에 관한 사례 연구 -용인시 채무제로화 정책을 중심으로)

  • Choi, Seonmi
    • The Journal of the Korea Contents Association
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    • v.18 no.3
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    • pp.472-485
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    • 2018
  • The purpose of this study is to analyze debt zeroing policy process of Yong-in city based on the Kingdon's Multiple Stream Framework in order to contribute to strengthening financial capacity and competitiveness of local governments. This study focused on the Yong-in case because the city had a local debt of about KRW 800 billion as of 2012, but it completed the debt repayment in early 2017. The results are as follows. First, policy problem streams are the perception of Yongin City's debt indicator, the failure of the LRT project, and the failure of sale of buildinglots of Yukbuk district. Second, in the political stream, there have been the election of new governors, cooperation of local administration and citizens like budget cut. Third, policy alternative streams are the reduction of large-scale investment projects, the expansion of revenues through the sale of idle shared properties, the increase of tax revenues, and the activation of light rail. As the each streams flowed independently, the window of policy change opened by the revitalization of the real estate market and the sale of buildinglots of Yukbuk distric and combined with other policy factors such as the activation of the light rail. In this process, the role of the policy entrepreneurs such as negotiation and persuasion of the related institutions influenced achieving tight fiscal policy. As a result of this policy output, Yongin City achieved zero debt. This study suggests that it is necessary not only the importance of the role of policy entrepreneurs but also of the administrative and citizen cooperation and the institutional complement such as a large scale of the investment review system.

A Case Study of Automation Management System of Damaged Container in the Port Gate (항만 게이트의 데미지 컨테이너 관리 자동화 시스템 구축 사례연구)

  • Cha, Sang-Hyun;Noh, Chang-Kyun
    • Journal of Navigation and Port Research
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    • v.41 no.3
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    • pp.119-126
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    • 2017
  • As container vessels get larger, container terminals are also likely to grow. The problem that arises is that the growing volume should be handled in the same amount of time as before. Container terminals are introducing an automation system in order to overcome the limitations of existing manual methods and to continuously reduce operating expenses. Because, Manual handling of carrying containers gate in and out of terminals causes inaccurate data, which results in confusion. An alternative is for containers to be labeled with barcodes that can be scanned into a system with a scanner, but this takes quite a long time and is inconvenient. A RFID system, also known as a gate automation system, can solve these problems by reducing the time of gate management with a technology that detects number identification plates, helping operators more efficiently perform gate management work. Having said that, with this system, when container damage is detected, gate operators make and keep documents manually. These documents, which are insufficient evidence in proving container damage, result in customer claims. In addition, it is difficult for gate operators and other workers to manage containers, exposing them to danger and accidents. This study suggests that if an automation system is introduced at gates, containers can be managed by a video storage system in order to better document damage The video system maintains information on container damage, allowing operators the ability to search for videos they need upon customer request, also allowing them to be better prepared for customer claims. In addition, this system reduces necessary personnel and risk of accidents near gates by integrating a wide range of work.

전기자동차 개발

  • 임성기
    • 전기의세계
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    • v.41 no.12
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    • pp.21-30
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    • 1992
  • 내연기관의 가솔린자동차보다 역사가 오래된 전기자동차는 상대적으로 주생성능과 가격 경쟁력의 열세로 그 자취를 감추었고 최근까지 주로 특수목적의 단거리 저속차량으로 사용되고 있다. 그러나 1890년대 후반부터 전세계가 자동차배기가스에 의한 대기오염과 지구온난화 현상등의 문제를 심각하게 공감하게 되었고 마침내 미국 캘리포니아주에서는 전가자동차의 강제판매를 규정화하게 이르렀다. 이 규정에 의하면 1998년도부터 차량 판매대수의 2%를 전기자동차 판매로 강제요구하고 있다. 이 비율은 2000녀도에 5% 2003년에는 10%로 늘어날 계획이다. 따라서 미국에 많은 자동차를 수출하고 있는 일본, 독일 및 여러 유럽국가에서는 이 사업에 막대한 자금을 투자하며 개발에 몰두하고 있다. 미국의 Big3도 에너지성의 도움으로 최근 USABC를 결성하여 전기자동차 개발에 박차를 가하고 있다. 지금까지 기존의 가솔린자동차 기술에 있어서 일본과 독일에 상대적 열세에 있었던 미국도 이번 캘리포니아주의 전기자동차 강제판매 규정에 따른 전기자동차 사업으로 미국자동차 시장의 새로운 판도를 조성하겠다는 의도인듯하다. 국내에서도 정부가 이 사업의 중요성을 심각히 인식하고 G7사업과제의 하나로 선정하여 산, 학, 연 각층의 전문가가 참여하여 성공적으로 개발을 마칠 수 있도록 적극 지원하고 있다. 지금까지의 평균주행성능을 보면 최고속도 100-120km/h, 일층전 최대주행거리 150-200km 정도이며, 아직 양산체제에 돌입하지 않았기 때문에 가격면에서 경쟁력이 없는 실정이다. 그러나 1990년도에 들면서 각종 요소부품들의 기술수준이 급성장을 이루어서 앞으로 10년정도 후면 성능과 가격면에서 가솔린자동차와 대등한 수준의 전기자동차 개발이 실현될 수 있으리라 예측된다.는 영향받지 않았다. Clonidine의 심박수 감소작용은 .뇌실내및 정맥내 diltiazem이나 nifedipine 처리후에 감약되었다. 5). 뇌실내 clonidine$(30{\mu}g)$ 처 리후 뇌실내 diltiazem$(400{\mu}g)$과 nifedipine$(350{\mu}g)$의 혈압하강및 심박수 감소효과는 영향 받지 않고 그대로 나타났다. 이상의 결과로 diltiazem과 nifedipine은 가토뇌내에서 methoxamine에 의한 혈압상승의 작용점인 alrfia-1 adrenoceptor의 흥분에는 영향을 미치지 못하나 clonidine의 작용점인 alpha-2 adrenoceptor의 흥분에 의한 혈압하강및 심박수 감소효과는 억제한다고 추론하였다.thin 함량은 110.6 mg/L로서 산업적인 생산성이 있는 것으로 나타났다. 이번 연구를 통하여 개발된 변이주 B76 및 이의 대량 발효를 위한 최종조건의 정립은 향후 astaxanthin의 산업적 생산공정에 필요한 기초자료로 이용될 것으로 기대된다.색총말내에 소형의 도형, 소형의 장형 연접소포 및 DENSE CORE VESICLE의 3가지 연접소포를 가지고 있었고 출현빈도수는 촉각엽에서 가장 큰 33%이었다. 제5형 신경연접은 축색종말내에 중등도크기의 원형, 대형의 원형연접소포 및 DENSE CORE VESICLE을 포함하였고 13%의 출현빈도수로 관찰되었다. 배추횐나비의 촉각에 있는 지각신경세포가 뇌의 촉각엽으로 뻗어 들어가 위의 5가지 신경연접중 어느 형을 형성하는지를 관찰하기 위하여 좌측 촉각의 기부를 제거하여 지각신경세포를 절단하였는데 그 결과, 좌측 촉각엽에서 제4형의 신경연접이 퇴행성 변화를 나타내었다.

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Prediction of Broadband Noise for Non-cavitation Hydrofoils using Wall-Pressure Spectrum Models (벽면변동압력을 이용한 비공동 수중익의 광대역소음 예측 연구)

  • Choi, Woen-Sug;Jeong, Seung-Jin;Hong, Suk-Yoon;Song, Jee-Hun;Kwon, Hyun-Wung;Kim, Min-Jae
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.25 no.6
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    • pp.765-771
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    • 2019
  • With the increase in the speed of ships and the size of ocean structures, the importance of flow noise has become increasingly critical in meeting regulatory standards. However, unlike active investigations in aeroacoustics fields for airplanes and trains, which are based on acoustic analogy methods for tonal and broadband frequency noise, only the discrete blade passing frequency noise from propellers is considered in marine fields. In this study, prediction methods for broadband noise in marine propellers and underwater appendages are investigated using FW-H Formulation1B, which can consider the mechanism of primary noise generation of trailing edge noise. The original FW-H Formulation 1B is based on the pressure correlation function tolackitsgeneralityandaccuracy. To overcome these limitations, wall-pressure spectrum models are adopted to improve the generality in fluid mediums. The comparison of the experimental results obtained in air reveals that the proposed model exhibits a higher accuracy within 5 dB. Furthermore, the prediction procedures for broadband noise for hydrofoils are established, and the estimation of broadband noise is conducted based on the results of the computational fluid dynamics.

A Study on the Implementation of Intelligent Navigational Risk Assessment System for High-risk Vessel using IoT Sensor Gateway (IoT 센서연계장치를 이용한 고위험선박의 지능형 운항위험 분석 시스템 개발에 대한 연구)

  • Kim, Do-Yeon;Kim, Kil-Yong;Park, Gyei-Kark;Jeong, Jung-Sik
    • Journal of the Korean Institute of Intelligent Systems
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    • v.26 no.3
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    • pp.239-245
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    • 2016
  • In the midst of continuing international recession, the rate of maritime traffic and marine leisure markets are consistently growing. The Republic of Korea controls the marine traffic volume through vessel traffic centers and various other management facilities. Nevertheless, the continuous growth and complexity of marine traffic is resulting in repeated occurrences of marine accidents. Recovery is very difficult in cases of human injuries or deaths caused by marine accidents due to its nature, and the scale of marine accidents is also becoming greater with advanced ship building technologies. Passenger ships, oil tankers, and other such vessels used for specific purposes requires a more detailed navigational status surveillance and analysis, and numerous research has been conducted with an objective for monitoring such special purpose vessels. However, the data elements transmitted from the ocean to the shore station are limited to AIS and ARPA. We are implementing IoT ship sensor collection and a syncing system capable of transmitting various ship sensing data to the shore station, and also proposing a Safe Navigation Status Analysis System utilizing the collected data.

The Aesthetic Experience in the Landscape of Memory (기억의 경관에서 미적 경험)

  • Son, Eun-Shin;Pae, Jeong-Hann
    • Journal of the Korean Institute of Landscape Architecture
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    • v.45 no.3
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    • pp.129-140
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    • 2017
  • This study aims to interpret the current landscape design of the place and landscape of memory, such as post-industrial parks and memorials that have an old, aging appearance from an aesthetic perspective. The objects of the study are large parks and open spaces that have collective memories for visitors. Visitors' aesthetic experience from these places and landscapes of memory could be explained by aesthetic concepts such as the sublime, nostalgia, and melancholy. Because these aesthetic concepts are associated with past traumas, visitors may be affected morbidly. However, due to the capability of the media to form an aesthetic experience when visitors visit a given place and landscape, visitors can autonomously adjust the distance to the place of memory and gain an aesthetic experience. The aesthetic experiences through the sublime, nostalgia, and melancholy are based on temporality and irreversibility. Temporality here refers to a characteristic of memory, and time in the place and landscape of memory and is based on the irreversibility of time, as time cannot go back. Both the place memory and the memory that is recalled from the combination with visitor's past memories and knowledge are two major factors involved in the construction of the aesthetic experience in the place and landscape of memory. The results of the present study are meaningful in that this study presents a framework for a better understanding and use of both the place memory and appreciators' memory in the design process of a place and landscape of memory and also criticizes a materialistic approach that fails to take into account the visitors' memories.