• 제목/요약/키워드: Compliance Effect

검색결과 568건 처리시간 0.025초

수치 해법을 이용하여 제진대에 부착된 가속도 센서의 진동 측정 (Using Numerical Solutions of the Vibration Measurement Accelerometers attached Vibration Isolator)

  • 신동호;이정우;이종원;오재응;이정윤
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2012년도 춘계학술대회 논문집
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    • pp.875-880
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    • 2012
  • According to the fixation detailed drawing and lightweight anger tendency of the product the vibration control of precision equipments is essential and establishes under the equipments. so It is important to know vibration characteristics of vibration isolator. For this reason the accelerometer attaches in vibration isolator and measures an acceleration response. The acceleration response which is measured will lead double integral and will be able to predict a displacement of vibration isolator. However, in compliance with the effect of the accelerometer can not be accurately. From this paper, mass, damping ratio and natural frequency of the accelerometers by changing the vibration isolator to predict the acceleration response and the results were compared.

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A study on the fracture toughness of seawater-absorbed carbon nanotube/epoxy/basalt composites

  • Kim, Man Tae;Rhee, Kyong Yop;Kim, Hyun Ju;Jung, Dong Ho
    • Carbon letters
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    • 제14권3호
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    • pp.190-192
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    • 2013
  • It has been demonstrated in a previous study that carbon nanotube (CNT)/epoxy/basalt composites produce better flexural properties than epoxy/basalt composites. In this study, mode I fracture tests were conducted using CNT/epoxy/basalt composites with and without seawater absorption in order to investigate the effect of the seawater absorption on the mode I fracture toughness ($G_{Ic}$) of the CNT/epoxy/basalt composites. The results demonstrated that the compliance of the seawater-absorbed specimen was larger than that of the dry specimen at the same crack length, while the opposite result was obtained for the fracture load. The $G_{Ic}$ value of the seawater-absorbed CNT/epoxy/basalt composites was approximately 20% lower than that of the dry CNT/epoxy/basalt composites.

수면호흡장애와 코막힘 (Sleep Disordered Breathing and Nasal Obstruction)

  • 정유삼
    • 수면정신생리
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    • 제12권2호
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    • pp.93-97
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    • 2005
  • Nasal obstruction may cause or aggravate sleep disordered breathing but exact pathogenesis is not clear. The possible mechanism could be combination of alteration in upper airway aerodynaimcs, loss of nasal reflex or sensation, effect of mouth opening, and a genetic predisposition. Anatomical narrowing of nasal airway cause more rapid airflow and induce more negative inspiratory air pressure. So, it increases collapsibility of pharyngeal airway. Loss of nasal sensation to airflow block nasal reflex. Mouth opening decreases the activity of pharyngeal airway dilator muscles and narrowing the pharyngeal airway may occur. The treatment of nasal obstruction should be done according to the cause. The causes of nasal obstruction are various from problems of external nasal opening to nasopharynx. Relief of nasal obstruction may not cure sleep disordered breathing always. In some mild obstructive sleep apnea patients, treatment of nasal obstruction only may cure sleep disordered breathing. In some severe sleep apnea patients, treatment of nasal obstruction may increase compliance of continous nasal positive airway pressure.

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기분장애의 치료에 있어서 약물의 Augmentation Strategies (Drug Augmentation Strategies in the Treatment of Mood Disdorder)

  • 정영인
    • 생물정신의학
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    • 제5권2호
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    • pp.155-161
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    • 1998
  • Mood disorder is a medical illness resulting from the disorder of CNS neurotransmission and its principal therapeutic tool is pharmacotherapy. Psychotherapeutic drugs for mood disorder have some clinical limitations which are due to no or partial response, decreased compliance for drug by the side effects, and delayed therapeutic effects. So, general hope of all clinicians that mood diorder will respond to a single psychotherapeutic agent may be the exception rather than the rule. Recently, combined drug treatments have become increasingly popular to overcome the clinical limitations of individual agent in mood disorder. Combined treatments are usually used for augmenting or initiating rapidly the effect of drug, and for treating different target symptoms or drug side effects. When combined treatments being tried, knowledge of the action mechanism, pharmacokinetics, and pharmacodynamics is crucial to cope with the possible adverse reactions of drugs.

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A Study on High Current Rectifier Systems with Mitigated Time-Varying Magnetic Field Generation

  • 김창우;서용석
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2010년도 하계학술대회 논문집
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    • pp.232-233
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    • 2010
  • This paper investigates occupational exposure to time-varying magnetic field generation in high power rectifier systems. Two different kinds of high power rectifier systems of 25kA are modeled and analyzed. The performance is compared and evaluated on the basis of exposure guidelines from ICNIRP. In order to focus on the qualitative effect of rectifier operation, the mechanical structure of current carrying conductors is simplified as infinite long bus-bar model and low frequency harmonic contents up to 65kHz are considered. Thyristor rectifier generates a significant amount of low frequency magnetic field harmonic contents both at ac and dc side of rectifier infringing the limit from ICNIRP. The multilevel rectifier-IGCT type has almost negligible field generation from ac input side and smaller harmonic contents in dc load side complying with ICNIRP guideline. This remarkable advantage of multilevel rectifier-IGCT type can lead to very simple site layout design for installation and cost-effective compliance to guideline of occupational exposure against magnetic field.

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Application of the compressive-force path concept in the design of reinforced concrete indeterminate structures: A pilot study

  • Seraj, Salek M.;Kotsovos, Michael D.;Pavlovic, Milija N.
    • Structural Engineering and Mechanics
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    • 제3권5호
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    • pp.475-495
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    • 1995
  • In the past, physical models have been proposed, in compliance with the concept of the compressive-force path, for the realistic design of various statically determinate structural concrete members. The present work extends these models so as to encompass indeterminate RC structural forms. Pilot tests conducted on continuous beams and fixed-ended portal frames have revealed that designing such members to present-day concepts may lead to brittle types of failure. On the other hand, similar members designed on the basis of the proposed physical models attained very ductile failures. It appears that, unlike current design approaches, the compressive-force path concept is capable of identifying those areas where failure is most likely to be triggered, and ensures better load redistribution, thus improving ductility. The beneficial effect of proper detailing at the point of contraflexure in an indeterminate RC member is to be noted.

균열진 구조물의 피로수명 연장을 위한 Patch 설계기법에 관한 연구 (A Study on Patch Design Technique for Fatigue Life Prolongation of Cracked Structures)

  • 한문식
    • 대한조선학회논문집
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    • 제29권2호
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    • pp.79-91
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    • 1992
  • 본 논문에서는 균열 보수에 사용되는 Patch와 균열진 판 사이에 컴프라이언스 개념을 적용하여 Patch된 균열진 판의 응력확대계수를 이론유도하고, 이에 대한 실험과 균열진전 거동규명을 통하여 그 유효성을 충분히 검증하였다. 또한, 이와같은 컴프라이언스를 이용한 이론방법을 바탕으로 균열진 구조물의 잔존수명이 고려된 Patch를 간단히 설계할 수 있는 기법을 제시하였다.

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가선계의 동특성 해석 (A Study on the Dynamic Characteristics of Catenary)

  • 최병두;김정수
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 1998년도 창립기념 춘계학술대회 논문집
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    • pp.525-532
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    • 1998
  • In this study, dynamic characteristics of catenary that supplies electrical power to high-speed trains is investigated. A particular emphasis is placed on the effect of droppers on the dynamic response of the contact wire, a dropper is an element that connects the contact wire with the messenger wire so as to maintain near uniform compliance, Finite element model compressing 3 spans is constructed. For the linear model, droppers are modeled as linear springs with various stiffness values. Modal analysis is performed to obtain the natural frequencies and modes and the variation in the modal density distribution for changing stiffness values are noted. Impulse response is also obtained through computer simulation. In practice, dropper is a nonlinear element with low stiffness in compression and high stiffness in tension. Hence, dropper can be modeled as a nonlinear spring with hi-directional stiffness values. Impulse and harmonic responses are obtained for the nonlinear model through simulation. The responses aye also compared with the linear cases.

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자체검사제도가 갖는 재해예방 효과 (The Importance of Self-Inspection in Accident Prevention)

  • 백종배
    • 한국안전학회지
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    • 제16권4호
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    • pp.175-181
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    • 2001
  • In compliance with the Industrial Safely and Health Acts, the owners/users have performed self-inspection at regular intervals to secure safety in the use of hazardous machinery, equipment and facilities However, securing safety, which is the goal of self-inspection, has not been thoroughly understood in most small businesses and factories. The objective of this research is to analyze the importance and effects of self-inspection in preventing accidents in businesses and factories that use hazardous machinery and facilities. The result shows that self-inspection has made a good contribution to the prevention of accidents. Most businesses and factories that responded the survey answered they have improved safety in the use of machinery and facilities through self-inspection, though the ways of self-inspection were not all the same. However, the result also reveals that there are rooms for further improvement in the areas of self-inspection intervals, self-inspection methods and the selection of self-inspection objects. This improvement is necessary to improve the effect of self-inspection and to minimize regulations of the government on business activities.

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신약개발과 안전성약리시험 가이드라인 (Drug Development and Guideline for Safety Pharmacology Studies)

  • 최기환;박인숙;임화경;오우용;왕소영;김소희;김주일;김동섭
    • 약학회지
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    • 제47권2호
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    • pp.104-109
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    • 2003
  • The present paper reviews the notion and comparison of the Korea Food and Drug Administration(KFDA) general pharmacology and the International Conference on Harmonisation (ICH) safety pharmacology. General pharmacology or safety pharmacology is termed the study to determine the potential of a compound to induce adverse pharmacological effects. KFDA general pharmacology studies have been considered an important component in drug safety assessment and these were originally referred to those designed to examine effects other than the primary therapeutics effect of a drug candidate. The KFDA notified the Guideline for General Pharmacology in 1997. Safety pharmacology studies were focused on identifying adverse effects on physiological functions. In the ICH came into place S7A Safety Pharmacology Studies for Human Pharmaceuticals in 2001. A new chemical entity should be assessed for its side effects, initially in those physiological systems which are generally agreed to be the key systems that are essential for life; these "core system" include the central nervous system, cardiovascular system and respiratory system in safety pharmacology studies. These studies should be performed in compliance with Good Laboratory Practice (GLP).