• 제목/요약/키워드: Conventional system

검색결과 14,428건 처리시간 0.047초

기존선 틸팅차량 시스템 설계에 관한 연구 (The Study for System Design of Tilting Car for Conventional Railroad)

  • 유원희;한성호;김남포;김길동;박광복
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2002년도 춘계학술대회 논문집
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    • pp.317-329
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    • 2002
  • This report was studied about system design of tilting car for speed up for conventional railroad of KNR. The maximum operating speed of Kyun-Pu line was recorded a 140km/h by saemaul train at 1985 and the average speed its is 107km/h now. The chungang line, janghang line and honam line of KNR had rebuilt to the electrified line for operation of tilting train. This report was described about the operation status of advanced countries, the operation situation of trains of KNR, system design for operation and speed up by EMU tilting train on the conventional railroad in the future.

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Effectiveness of Friction Loss Calculation Used for Water Mist Fire Extinguishing System on Marine Vessels

  • Lee Kyung-Woo;Kim You-Taek;Lee Young-Ho;Kim Mann-Eung
    • Journal of Advanced Marine Engineering and Technology
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    • 제29권1호
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    • pp.86-97
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    • 2005
  • Nowadays, Water Mist Fire Extinguishing System is increasingly used in maritime field for various application. The fire extinguishing capability of the system should be verified by hydraulic calculation in the same manner as the conventional water based fire extinguishing system such as sprinkler system. water spray system and etc. Additionally, the review of effectiveness of friction loss calculation method used for hydraulic calculation is needed because the pipe flow characteristic of its piping system has higher Reynolds number than that of the conventional system. In this paper the review work was carried out based on the NFPA Code 750.

Design and Implementation of PDA-based Image Surveillance System for Harbor Security using IP Camera

  • Shim, Joon-Hwan
    • 한국항해항만학회지
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    • 제31권9호
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    • pp.779-784
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    • 2007
  • This paper describes a new progressive embedded Internet Protocol(IP) camera available for real-time image transmission. It was applied for ship safety and security on seashore area. The functions of developed embedded system was more effective and excellent than conventional systems. Nowadays, each nation has established harbor security systems to jump up their ports to international port. Recently Incheon port has tried to change man security into center security system used by image security system. The security system of Incheon port has some advantages like effectivity of security system and reduction of manpower and cost, installed by image security system with CCTV cameras at the entrance gate and around the fence. Thus in this paper, we have designed and implemented a Personal Digital Assistants(PDA) based Image Surveillance System for Harbor Security using IP Camera under ubiquitous environment. This system has big advantages which are more effective in an emergency and low cost and small manpower than conventional systems.

율무 재배의 기계화 일관 작업체계가 시간 및 경비에 미치는 영향 (Effect of Merchanized and Intergrated Working System of Job's Tears Cultivation on the Time and Expenditure)

  • 강치훈;김기중;유창재;김두환
    • 한국자원식물학회지
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    • 제14권1호
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    • pp.71-76
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    • 2001
  • 본 실험은 율무 재배시 파종에서 수확까지의 기계화 일관 작업 체계가 시간 및 경비의 절감에 미치는 영향을 조사하기 위하여 수행되었다. 출현율은 관행구 62%에 비해 기계화구에서 50%로 낮았다. 작업체계별 10a 당 총 작업시간은 관행구 2,273 분에 비해 기계화구가 90%절감된 230분 이었다. 작업체계별 10a 당 총 경비는 관행구 189,781원에 비해 기계화구가 42% 절감된 111,061원이었다. 작업체계별 출현기, 출수기 및 개화기는 각각 5월 16일, 7월 25일 및 8월 9일로 동일하였다. 작업체계별 생육특성은 비슷하였으나 조명나방 이병주율이 기계화구 3.0%에 비해 관행구에서 13.3%로 높았다. 수량구성 요소는 관행구에 비해 기계화구가 높아서 기계화 구의 조곡 수량은 351kg/10a으로 관행구 309kg에 비해 14% 높았다.

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Fast and Efficient Method for Fire Detection Using Image Processing

  • Celik, Turgay
    • ETRI Journal
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    • 제32권6호
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    • pp.881-890
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    • 2010
  • Conventional fire detection systems use physical sensors to detect fire. Chemical properties of particles in the air are acquired by sensors and are used by conventional fire detection systems to raise an alarm. However, this can also cause false alarms; for example, a person smoking in a room may trigger a typical fire alarm system. In order to manage false alarms of conventional fire detection systems, a computer vision-based fire detection algorithm is proposed in this paper. The proposed fire detection algorithm consists of two main parts: fire color modeling and motion detection. The algorithm can be used in parallel with conventional fire detection systems to reduce false alarms. It can also be deployed as a stand-alone system to detect fire by using video frames acquired through a video acquisition device. A novel fire color model is developed in CIE $L^*a^*b^*$ color space to identify fire pixels. The proposed fire color model is tested with ten diverse video sequences including different types of fire. The experimental results are quite encouraging in terms of correctly classifying fire pixels according to color information only. The overall fire detection system's performance is tested over a benchmark fire video database, and its performance is compared with the state-of-the-art fire detection method.

A Study on Energy Saving of IMV Circuit using Pressure Feedback

  • Park, Hyoung Gyu;Nahian, Syed Abu;Anh, Kyoung Kwan
    • 드라이브 ㆍ 컨트롤
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    • 제13권4호
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    • pp.31-44
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    • 2016
  • In recent hydraulic actuation systems, conventional hydraulic spool valves with pressure compensators are becoming less popular, after the introduction of the independent metering concept for valves. Within this concept, four valves are needed for actuating a single cylinder. Subsequently, this increases the freedom of controlling both chamber pressures of the cylinder, and it then provides for electronically-controlled pressure compensation facilities. Additionally, this has the potential to save valuable energy. The primary focus of this paper is to develop a new generation of hydraulic circuits using the independent metering valve (IMV). This configuration can function well as a conventional IMV circuit while providing better pressure control. We first describe the working principles of five distinct modes of the proposed IMV system. Then, mathematical models for each working mode are presented. Finally, we present numerical simulations that have been carried out to evaluate the system performance, in comparison with that of the conventional IMV configuration. The simulation results demonstrate that the performance of the new IMV configuration is superior to the conventional IMV system in terms of energy savings.

Twin-jet 대향류에서 메탄 비예혼합화염에 대한 수치적 연구 (Numerical Study on Non-premixed Methane Flames in Twin-jet Counterflow)

  • 천강우;김준홍;정석호
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2004년도 제28회 KOSCO SYMPOSIUM 논문집
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    • pp.49-56
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    • 2004
  • A two-dimensional twin-jet counterflow system has been designed, in which two streams from two double-slit nozzles form a counterflow. This flow system enables one to systematically investigate various effects on non-premixed flames, including the non-premixed flame interaction, the edge flame behavior and the effect of curvature. Non-premixed flame interaction in the twin-jet counterflow system has been investigated numerically for methane fuel diluted with nitrogen. Three types of non-premixed flame(conventional counterflow flame, crossed twin-jet flame and petal shaped flame) were simulated depending on the combination of fuel/oxidizer supply to each nozzle. The extinction characteristics of non premixed methane flame in the twin-jet counterflow have been investigated numerically. The boundary of the existence of petal-shaped flames was identified for the twin-jet counterflow flames. Due to the existence of the unique petal-shaped flames, the extinction boundary for the twin-jet counterflow can be extended significantly compared to that for the conventional counterflow non-premixed flames, through the interaction of two flames. Through the comparison of the crossed twin-jet flame and the conventional counterflow flame, structure of the crossed twin-jet counterflow flame is analysed. Through the comparison of the petal shaped flame and the conventional counterflow flame, the extension of the extinction boundary for the twin-jet counterflow is investigated.

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사진측량을 이용한 초구장 기본 계획에 관한 연구 (A Study on the Basic Planning of Country Club Using Photogrammetry)

  • 유복모;조기성;박성규
    • 한국측량학회지
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    • 제8권1호
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    • pp.31-40
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    • 1990
  • 본 연구는 사친 측량을 이용한 효율적인 초구장 기본 계획을 수립하고자 연구 대상지를 선정하여 종래 방법과 사진측량 방법을 비교 분석하였다. 또한, 대상지 항공사진과 지형도를 이용하여 사친 판독에 의해 식생, 수계도를 작성하고, 대상지를 격자로 구성하여 수치지형모델에 의한 지형 변화 및 경관을 예측하므로서 계획에 필요한 여러 요소를 종래방법과 비교 고찰하였다. 본 연구 결과 사진 판독에 식생도 및 수계도를 작성하므로서 기존 조사방법 보다 세밀한 결과를 얻을 수 있었고, 수치지형모델을 이용하여 지형, 경관 및 수계 등의 변화를 표현, 예측하므로서 우수처리, 경관, 조경 계획을 효율적으로 할 수 있었다. 또한, 항공사진과 지형도를 병용하므로서 토지 이용 계획과 기타 계획에 관하여 종래 방법보다 효율적임을 제시할 수 있었다.

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Digora$\textregistered$ 영상시스템을 이용한 인접면 인공 치아우식병소의 진단능에 관한 연구 (A Study on the Diagnostic Detection Ability of the Artificial Proximal Caries by Digora$\textregistered$)

  • 오경란;최의환;김재덕
    • 치과방사선
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    • 제28권2호
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    • pp.415-433
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    • 1998
  • Digora system is an intraoral indirect digital radiography system utilizing storage phosphor image plate. It has wide dynamic range which allows it to decrease the patient s exposure time and may increase diagnostic ability through image processing (such as edge enhancement, grey scale conversion, brightness change, and contrast enhancement). And also, it can transmit and storage image information. The purpose of this study was to evaluate the diagnostic ability of artificial proximal caries between Conventional radiograph and Digora images(unenhanced image, brightness & contrast controlled image, and edge enhanced image). ROC(Receiver Operating Characteristic) analysis, paired t-tests, and F-tests were done for the statistical evaluation of detectability. The following results were acquired: 1. In Grade I lesions, the mean ROC areas of Conventional radiograph, Digora unenhanced image, Digora controlled image, and Digora edge enhanced image were 0.953, 0.933, 0.965, 0.978 (p>0.05). 2. In Grade II lesions, the mean ROC areas of Conventional radiograph, Digora unenhanced image, Digora controlled image, and Digora edge enhanced image were 0.969, 0.964, 0.988, 0.994. Among theses areas, there was just statistical significance between Diagnostic abilities of Digora edge enhanced image and Conventional radiograph (p<0.05). 3. In the Interobserver variability, the ROC curve areas of Digora edge enhanced image was lowermost in these areas, regardless of the Carious lesion depths. In conclusion, intraoral indirect digital system, Digora system, has the potential possibility as an alternative of Conventional radiograph in the diagnosis of proximal caries.

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Conventional한 방식과 CAD/CAM System을 이용한 완전 무치악 환자 동시 수복 증례 (The treatment of an edentulous patient with conventional complete denture and CAD/CAM complete denture)

  • 조성윤;이준석
    • 대한치과보철학회지
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    • 제58권1호
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    • pp.42-49
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    • 2020
  • 무치악 환자에게서 의치의 제작은 통상적이고 전통적인 방법을 따를 경우 최종 의치 장착까지 여러 단계를 거쳐야 하며 이로 인한 환자의 잦은 내원이 불가피하다. 또한 기공 과정 상에서 나타나는 중합수축에 의한 오차나, 의치의 파절이나 분실 시 빠른 재제작의 어려움 등의 단점이 존재하였다. 하지만 최근 치과 분야에서 computer-aided design and computer-aided manufacturing (CAD/CAM) System이 사용되기 시작하였고, 의치 제작에까지 그 영역을 넓히기 시작하였다. CAD/CAM System을 이용하여 의치를 제작하면 첫 번째 내원 시에 인상채득과 악간관계의 기록, 인공치의 선택 등이 동시에 이루어지고 두 번째 내원 시 의치의 장착이 가능하기 때문에 환자의 내원 횟수와 진료시간을 감소시킬 수 있다. 또한 3D-Printing 기술을 이용하기 때문에 중합수축에 의한 기공 오차를 감소시킬 수 있다. 현재 상용화 되어 있는 CAD/CAM System을 사용한 의치로는 DENTCA CAD/CAM denture (DENTCA Inc., Los Angeles, CA, USA)가 있다. 본 증례에서는 상, 하악 완전 무치악 환자에게서 conventional 한 방법과 DENTCA CAD/CAM Denture System을 사용하는 방법을 동시에 사용하여 두 쌍의 총의치로 수복함으로써 발음, 저작, 연하 등의 기능적인 측면뿐만 아니라 심미적인 측면에서도 양호한 결과를 얻었기에 이를 보고하고자 한다.