• 제목/요약/키워드: Passive structure

검색결과 776건 처리시간 0.026초

소리의 특성 및 청지각기능에 대한 고찰 (A Study on the Nature of Sound and the Hearing Mechanism)

  • 이정학;김진숙
    • 음성과학
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    • 제5권1호
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    • pp.167-179
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    • 1999
  • The hearing mechanism is a complicated system. Sound is generated by a source that sends out air pressure or power. The pressure or power makes the sound waves. These waves reach the eardrum, or tympanic membrane, which vibrates at a rate and magnitude proportional to the nature of the sound waves. The tympanic membrane transforms this vibration into the mechanical energy in the middle ear, which in turn converts it to the hydraulic energy in the fluid of the inner ear. The hydraulic energy stimulates the sensory cells of the inner ear which send neuroelectrical impulses to the central auditory nervous system. The passive perception of auditory information starts just here. The listener gives attention to the speech sound, differentiates the sound from background noise, and integrates his experience with similar sounds. The listener then puts all of these aspects of audition into the context of the moment to identify the nature of sound. This has a major role in human communication. This paper provides an overview of the nature and characteristics of sound, the structure and function of the auditory system, and the way in which sound is processed by the auditory system.

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동일한 인접구조물의 효율적 진동제어방안 (Efficient Vibration Control Approach of Two Identical Adjacent Structures)

  • 옥승용
    • 한국안전학회지
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    • 제29권3호
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    • pp.56-63
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    • 2014
  • This study proposes a new control approach for efficient vibration suppression of two identical adjacent structures. The conventional control approach of two adjacent structures is to interconnect the two structures with passive, semi-active or active control devices. However, when the two adjacent structures are identical to each other, their dynamical behaviors such as frequency and damping properties are also the same. In this case, the interconnected control devices cannot exhibit the dissipative control forces on the both structures as expected since the relative displacements and velocities of the devices become close to zero. In other words, the interconnection method does not work for the twin structures as enough as expected. In order to solve this problem, we propose several new control approaches to effectively and efficiently reduce the identically-fluctuating responses of the adjacent structures with minimum control efforts. In order to demonstrate the proposed control systems, the proposed several control systems are optimally designed and their control performances are compared with that of the conventional optimal control system where each TMD(tuned mass damper) is installed in each structure for independent control purpose. The simulated results show that one of the proposed control systems(System 04) is able to guarantee enhanced control performance compared with the conventional system.

Radio Frequency Plasma Power변화에 따른 ITO 특성 및 OLED의 광학적 특성 (Optical Properties of Organic Light Emitting Diode and Characteristics of ITO by Variation of Radio Frequency Plasma Power)

  • 기현철;김회종;홍경진;김은미;구할본
    • 한국전기전자재료학회논문지
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    • 제22권1호
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    • pp.81-85
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    • 2009
  • We has been analysed optical properties of OLED(organic light emitting diode) and characteristics of ITO(Indium Tin Oxide) in terms of $O_2$ plasma treatment for manufacturing high efficiency OLED, RF power of $O_2$ plasma was changed 25, 50, 100, 200 W. $O_2$ gas flow, gas pressure and treatment time were fixed. Sheet resistance and surface roughness of ITO were measured by Hall-effect measurement system and AFM, respectively. The ranges of sheet resistance and surface roughness were $5.5{\sim}6,06\;{\Omega}$ and $2.438{\sim}3.506\;nm$ changing of RF power, respectively, PM(Passive Matrix)OLED was fabricated with the structure of ITO(plasm treatment)/TPD($400\;{\AA}$)/$Alq_3(600\;{\AA})$/LiF($5\;{\AA}$)/Al($1200\;{\AA}$). Turn-on voltage of PMOLED was 7 V and luminance was $7,371\;cd/m^2$ at the RF power of 25 W, $O_2$ plasma treatment of ITO surface was result in lowering the operating voltage and improving luminance of PMOLED.

소셜 네트워크 서비스의 은유적 특성 연구 (A Study on Metaphor Characteristics of Social Network Service)

  • 한혜원;문아름
    • 디지털콘텐츠학회 논문지
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    • 제15권5호
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    • pp.621-630
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    • 2014
  • 본 연구는 G. 레이코프와 M. 존슨이 제시한 '개념적 은유'를 적용해 소셜 네트워크 서비스의 은유적 특성을 분석하는 것을 목적으로 한다. 소셜 네트워크 서비스는 일방향적 소통만 가능했던 기존 매체와는 달리, 사용자가 참여적으로 자신의 일상을 표현하고 타인의 서사를 해석하는 과정을 통해서 그 텍스트를 확장한다. 기존 매체에서 수동적이던 독자가, SNS에서 적극적인 발화자로 전환될 수 있었던 가장 큰 이유는 SNS에 내재된 은유적 속성 때문이다. 이에 본 연구에서는 SNS 사용자 텍스트의 생성 및 해석 과정을 '근원영역'과 '목표영역'을 중심으로 고찰했다. 이후 은유적 속성을 통해 나타난 사용자 텍스트의 생성구조를 폴 리쾨르의 삼중 미메시스를 통해 증명했다. SNS를 환유로 전제했던 기존의 연구 관점과 달리, 본 연구는 SNS의 은유적 특성 및 의미를 제시했다는 점에서 그 의의가 있다.

Numerical verification of a dual system's seismic response

  • Phocas, Marios C.;Sophocleous, Tonia
    • Earthquakes and Structures
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    • 제3권5호
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    • pp.749-766
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    • 2012
  • Structural control through integration of passive damping devices within the building structure has been increasingly implemented internationally in the last years and has proven to be a most promising strategy for earthquake safety. In the present paper an alternative configuration of an innovative energy dissipation mechanism that consists of slender tension only bracing members with closed loop and a hysteretic damper is investigated in its dynamic behavior. The implementation of the adaptable dual control system, ADCS, in frame structures enables a dual function of the component members, leading to two practically uncoupled systems, i.e., the primary frame, responsible for the normal vertical and horizontal forces and the closed bracing-damper mechanism, for the earthquake forces and the necessary energy dissipation. Three representative international earthquake motions of differing frequency contents, duration and peak ground acceleration have been considered for the numerical verification of the effectiveness and properties of the SDOF systems with the proposed ADCS-configuration. The control mechanism may result in significant energy dissipation, when the geometrical and mechanical properties, i.e., stiffness and yield force of the integrated damper, are predefined. An optimum damper ratio, DR, defined as the ratio of the stiffness to the yield force of the hysteretic damper, is proposed to be used along with the stiffness factor of the damper's- to the primary frame's stiffness, in order for the control mechanism to achieve high energy dissipation and at the same time to prevent any increase of the system's maximum base shear and relative displacements. The results are summarized in a preliminary design methodology for ADCS.

Performance evaluation of bubble pump used on solar water heating system

  • Xuesong, Li;Park, Gi-Tae;Kim, Pil-Hwan;Chung, Han-Shik;Jeong, Hyo-Min
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2007년도 동계학술발표대회 논문집
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    • pp.416-422
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    • 2007
  • The application analysis of bubble pump on the domestic solar water heater system is presented. The system investigated in this study is a passive device, self pumping and self regulating. It was test to use the bubble pump on solar water heater system. The test experiment has been taken on the existed vacuum tube about the efficiency, working fluid temperature and pressure and circulated power. In order to check the working temperature and working pressure effectively, the bubble pump was test separated from the solar water heater. The equipment consists of the bubble pump, heater and heat exchanger. The main structure of bubble pump was design depend on the character of two phase flow. The complete system was instrumented to measure pressures, temperatures and their relationship with the solar radiation intensity. The theory analysis of design bubble pump has been given and the experiment result analysis has been included in the paper.

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비선형 전변동을 이용한 초점거리 변화 기반의 3 차원 깊이 측정 방법 (3D Shape Recovery Using Image Focus through Nonlinear Total Variation)

  • 무하마드 타릭 마흐무드;최영규
    • 반도체디스플레이기술학회지
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    • 제12권2호
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    • pp.27-32
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    • 2013
  • Shape From Focus (SFF) is a passive optical technique to recover 3D structure of an object that utilizes focus information from 2D images of the object taken at different focus levels. Mostly, SFF methods use a single focus measure to compute image focus quality of each pixel in the image sequence. However, it is difficult to recover accurate 3D shape using a single focus measure, as different focus measures perform differently in diverse conditions. In this paper, a nonlinear Total Variation (TV) based approach is proposed for 3D shape recovery. To improve the result of surface reconstruction, several initial depth maps are obtained using different focus measures and the resultant 3D shape is obtained by diffusing them through TV. The proposed method is tested and evaluated by using image sequences of synthetic and real objects. The results and comparative analysis demonstrate the effectiveness of our method.

복합한방치료로 호전된 방아쇠 무지증 환자 증례보고 (A Case Report on Patient with Trigger Thumb Improved by Complex Korean Medical Treatment)

  • 이지인;송호섭
    • Journal of Acupuncture Research
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    • 제32권1호
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    • pp.141-147
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    • 2015
  • Objectives : The purpose of this study was to report a case of patient with trigger thumb which improved by Meridian Tendino-musculature Acupuncture therapy, Moxubustion and Bee-Venom pharmacoacupuncture. Methods : In this study, we have conducted Meridian Tendi-musculature Acupuncture therapy, Bee-Venom Pharmacopuncture and Moxibustion treatment, on the basis of anatomical structure on the patient who was diagnosed of trigger thumb with pain, edema and motional restriction of the thumb. Furthermore, Electroacupuncture had been implemented with acupuncture therapy, and also passive exercise therapy had been conducted before and after the treatment to enhance the effect. The patient was assessed for trigger thumb-related symptoms by Visual Analogue Scale (VAS) score and Quinnell's Classification of triggering. Results : Quinnell's triggering grade & VAS score had decreased considerably after 18 sessions of treatment. Conclusions : It can be deducted that symptoms of Trigger thumb could be improved by Meridian Tendino-musculature Acupuncture therapy, Moxibustion and Bee Venom Pharmacopuncture treatment.

Corrosion Mechanism and Bond-Strength Study on Galvanized Steel in Concrete Environment

  • Kouril, M.;Pokorny, P.;Stoulil, J.
    • Corrosion Science and Technology
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    • 제16권2호
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    • pp.69-75
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    • 2017
  • Zinc coating on carbon steels give the higher corrosion resistance in chloride containing environments and in carbonated concrete. However, hydrogen evolution accompanies the corrosion of zinc in the initial activity in fresh concrete, which can lead to the formation of a porous structure at the reinforcement -concrete interface, which can potentially reduce the bond-strength of the reinforcement with concrete. The present study examines the mechanism of the corrosion of hot-dip galvanized steel in detail, as in the model pore solutions and real concrete. Calcium ion plays an important role in the corrosion mechanism, as it prevents the formation of passive layers on zinc at an elevated alkalinity. The corrosion rate of galvanized steel decreases in accordance with the exposure time; however, the reason for this is not the zinc transition into passivity, but the consumption of the less corrosion-resistant phases of hot-dip galvanizing in the concrete environment. The results on the electrochemical tests have been confirmed by the bond-strength test for the reinforcement of concrete and by evaluating the porosity of the cement adjacent to the reinforcement.

Overview of the Benefits of Structural Fire Engineering

  • Jowsey, Allan;Scott, Peter;Torero, Jose
    • 국제초고층학회논문집
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    • 제2권2호
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    • pp.131-139
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    • 2013
  • The field of structural fire engineering has evolved within the construction industry, driven largely by the acceptance of performance-based or goal-based design. This evolution has brought two disciplines very close together - that of structural engineering and fire engineering. This paper presents an overview of structural systems that are frequently adopted in tall building design; typical beams and columns, concrete filled steel tube columns and long span beams with web openings. It is shown that these structural members require a structural analysis in relation to their temperature evolution and failure modes to determine adequate thermal protection for a given fire resistance period. When this is accounted for, a more explicit understanding of the behaviour of the structure and significant cost savings can be achieved. This paper demonstrates the importance of structural fire assessments in the context of tall building design. It is shown that structural engineers are more than capable of assessing structural capacity in the event of fire using published methodologies. Rather than assumed performance, this approach can result in a safe and quantified design in the event of a fire.