• 제목/요약/키워드: Improvement devices

검색결과 1,311건 처리시간 0.026초

Dimension Enhancement Design of Bracket for Strength Improvement of the Bus Bare Chassis in which Shape is Fixed

  • Kwon, Young Woong
    • International journal of advanced smart convergence
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    • 제12권4호
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    • pp.443-450
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    • 2023
  • One of the basic tasks in the automobile manufacturing process is to design a bare chassis, which is the basic frame of a vehicle, and a bracket is a member connecting various devices to the frame. Bracket, which is a member connecting the engine, transmission, and suspension, which are the core devices of driving and operating the vehicle, to the frame, must maintain safety during vehicle operation. If the bracket connecting the various devices constituting the vehicle to the frame does not have durability, serious accidents may occur during operation of the vehicle. In this study, we performed stress analysis on the brackets installed in the bare chassis of the 25-passenger bus in the development stage. Based on the stress analysis performed, an improved bracket dimension was proposed.

Coordinated Wide-Area Regulation of Transmission System for Voltage Profile Improvement and Power Loss Reduction

  • Asadzadeh, Babak;Golshannavaz, Sajjad
    • Transactions on Electrical and Electronic Materials
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    • 제18권5호
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    • pp.279-286
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    • 2017
  • In this paper, an optimal approach for the wide-area regulation of control devices in a transmission network is proposed. In order to realize an improved voltage profile and reduced power loss, existing devices such as tap-changing transformers, synchronous machines, and capacitor banks should be controlled in a coordinated and on-line manner. It is well-understood that phasor measurement units in transmission substations allow the system operators to access the on-line loading and operation status of the network. Accordingly, this study proposes efficient software applications that can be employed in area operation centers. Thus, the implanted control devices can be regulated in an on-line and wide-area coordinated approach. In this process, efficient objective functions are devised for both voltage profile improvement and power loss reduction. Subsequently, sensitivity analysis is carried out to determine the best weighting factors for these objectives. Extensive numerical studies are conducted on an IEEE 14-bus test system and a real-world system named the Azarbayjan Regional Transmission Network. The obtained results are discussed in detail to highlight the promising improvements.

새로운 층을 삽입한 고효율 고발광의 OLEDs 제작 및 그 특성 (Improvement of efficiency and brightness by insertion of the novel layer in OLEDs)

  • 김영민;이주원;박정수;배성진;백경갑;장진;성만영;주병권;김재경
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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    • pp.108-111
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    • 2004
  • An efficiency and brightness of the Organic Light-emitting Diodes(OLEDs) by insertion of the novel layer between a singlet emitter and an electron transporting layer without doping processes, has been improved. The novel layers named as the K-M1 and K-M2 layers have shown the excellent improvement in the carrier balance and recombination efficiency. New devices using the K-M1 and K-M2 layers have shown a high efficiencies of over 15cd/A and 61m/W$(at\;20mA/cm^2)$, and brightness of over $16,000cd/m^2(at\;100mA/cm^2)$, respectively.

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수학과 수행평가의 문제점 분석 및 그 개선방안에 관한 연구 (A Study on the Problem Analysis and the Way of Improvement in Mathematical Performance Assessment)

  • 정덕찬
    • 한국학교수학회논문집
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    • 제3권2호
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    • pp.133-154
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    • 2000
  • The purpose of this study is to analyze theoretically suggested performance test and find out the actual conditions is math class at high schools and to suggest some devices for improvement for the various problems. To achieve this goal of study, I applied a performance test to the first graders of high school for one semester, and analyzed various phenomena which appeared during its practice. I made several questionnaire based on the materials of an academic seminar, "Several questions and devices for the improvement on mathematics performance test" And through the analysis, I pointed several problems of the performance test and proposed alternative plans. Several practical alternatives can be suggested for the problems appeared in the operation of performance test. The most important thing than any other technical solution in teachers′ diverse endeavor and enthusiastic research attitude to overcome the difficulties. Teachers′ spontaneousness is the foundation to enhance their own specialty and eradicate the propriety of the performance test.

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Comparison of Resonance Characteristics in FBAR Devices by Thermal Treatments

  • Mai Linh;Song Hae-il;Yoon Giwan
    • Journal of information and communication convergence engineering
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    • 제3권3호
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    • pp.137-141
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    • 2005
  • The paper presents some methods to improve characteristics of film bulk acoustic resonator (FBAR) devices. The FBAR devices were fabricated on Bragg reflectors. Thermal treatments were done by sintering and/or annealing processes. The measurement showed a considerable improvement of return loss $(S_{11})$ and quality factor $(Q_{s/p}).$ These thermal treatment techniques seem very promising for enhancing FBAR resonance performance.

유리창 외부 부착형 청소장치의 비상상황 시나리오 도출 (Emergency Scenarios of Rail-mounted Window Cleaning System)

  • 김균태;전영훈
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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    • pp.244-245
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    • 2019
  • Recently, a variety of window cleaning devices have been developed. There are, however, few cases of anticipated problems and countermeasures that may arise after these devices are installed. Therefore, in this study, the emergency condition was derived and the emergency scenario was derived for the rail-mounted cleaning device. Emergency scenarios and countermeasures derived from this study will be used for continuous improvement and supplementation of cleaning devices through prototyping and testing.

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블루투스 피코넷을 이용한 디스플레이 장치의 무선화 (A study on performance of the wireless of display devices using Piconet of the Bluetooth)

  • 강태규;김광선;김철환;이기서
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2003년도 춘계학술대회 논문집
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    • pp.480-486
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    • 2003
  • This paper proposes the connection without cables among display devices in a train using piconet of the Bluetooth. Nowadays, each train has a number of the display devices that are connected with many cables to lead the passengers, so it has the waste of resource and factor of fault. This paper proposes the improvement schemes of those problems in a train using piconet of the bluetooth with low cost, low power, and high security.

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TTX 차량의 능동 현가장치 설치 및 수정 작업 개선을 위한 대차/차체 인터페이스 볼스터 개발 (Bogie/Carbody Interface Bolster Development for the Installation of Active Suspensions and the Modification Operation Improvement of TTX Vehicle)

  • 김형준;박성태;강광호;이원상
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 춘계학술대회 논문집
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    • pp.28-34
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    • 2011
  • The carbody underframe of TTX vehicle should be modified a lot for the installation of new devices such as an active suspension system between the bogie and the carbody of TTX vehicle, because the carbody underframe is one body structure consisting of a center sill welded with a carbody bolster. Modification operation of the carbody takes a lot of time and cost, because the huge sized carbody structure should be moved to a machining apparatus and machined to guarantee the manufacture accuracy of new device installation brackets. For this reason, modification operation improvement is needed to install new devices more efficiently between the bogie and the carbody. This paper introduce the development of 'bogie/carbody interface bolster' that not only supports the carbody weight but also enables new devices to be installed more efficiently between the bogie and the carbody. This development has advantage to reduce working time and cost to install new devices such as an active suspension system between the bogie and the carbody by minimizing the modification of the carbody of TTX vehicle.

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Resonance Characteristic Improvement of ZnO-Based FBAR Devices Fabricated on Thermally Annealed Bragg Reflectors

  • Yim, Mun-Hyuk;Kim, Dong-Hyun;Linh Mai;Giwan Yoon
    • Journal of information and communication convergence engineering
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    • 제1권4호
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    • pp.199-204
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    • 2003
  • In this paper, we present the thermal annealing effects of the W/$SiO_2$ multi-layer reflectors in ZnO-based FBAR devices with cobalt (Co) electrodes in comparison with those with aluminum (Al) electrodes. Various thermal annealing conditions have been implemented on the W/$SiO_2$ multi-layer reflectors formed on p-type (100) silicon substrates. The resonance characteristics could be significantly improved due to the thermal annealing and were observed to depend strongly on the annealing conditions applied to the reflectors. Particularly, the FBAR devices with the W/$SiO_2$ multi- layer reflectors annealed at $400^{\circ}C$/30min have shown superior resonance characteristics in terms of return loss and quality-factor (Q-factor). In addition, the use of Co electrodes has resulted in further improvement of the resonance characteristics as compared with the Al electrodes. As a result, the combined use of both the thermal annealing and Co electrodes seems very useful to more effectively improve the resonance characteristics of the FBAR devices with the W/$SiO_2$ multi-layer reflectors.

국산 의료기기 사용률과 사용자 및 관리자 인식 조사를 통한 국산 의료기기 개선 방안 (Suggest Improvement for Medical Device Made in Korea by the Investigation of Domestic Medical Device Percentage and Survey of Medical Device Users and Manager)

  • 이정현
    • 재활복지공학회논문지
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    • 제11권4호
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    • pp.299-306
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    • 2017
  • 국산 의료기기 산업에 대한 다양한 투자와 신기술 도입에 따라 국내의료기기 산업은 비약적인 증가를 하고 있으나 국내 대형의료기관의 국산의료기기 사용률은 여전히 저조한 것으로 조사되고 있다. 본 논문에서는 국내 대형병원에서의 국산 의료기기 사용률과 사용자 및 관리자의 인식조사를 수행하여 국산의료기기의 개선점을 제시하였다. 이를 위해 국내 4곳의 국립대학교병원을 대상으로 전체 의료기기의 종류와 국산 의료기기 사용률에 대한 조사를 진행하고 이를 바탕으로 의료기기 중 중점조사 대상 의료기기를 선정하였다. 중점조사대상 의료기를 대상으로 고장통계와 사용자 인식조사를 수행하였으며 이를 통해 중점조사대상 의료기기의 개선사항을 제시하였다.