• 제목/요약/키워드: physical function tests

검색결과 293건 처리시간 0.034초

Ballistic behavior of steel sheet subjected to impact and perforation

  • Jankowiak, Tomasz;Rusinek, Alexis;Kpenyigba, K.M.;Pesci, Raphael
    • Steel and Composite Structures
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    • 제16권6호
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    • pp.595-609
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    • 2014
  • The paper is reporting some comparisons between experimental and numerical results in terms of failure mode, failure time and ballistic properties of mild steel sheet. Several projectile shapes have been considered to take into account the stress triaxiality effect on the failure mode during impact, penetration and perforation. The initial and residual velocities as well as the failure time have been measured during the tests to estimate more physical quantities. It has to be noticed that the failure time was defined using a High Speed Camera (HSC). Thanks to it, the impact forces (average and maximum level), were analyzed using numerical simulations together with an analytical description coupled to experimental observations. The key point of the model is the consideration of a shape function to define the pulse loading during perforation.

개의 뇌하수체 의존성 부신 피질 기능 항진증에서의 selegiline 적용 (Use of selegiline in 3 Cases of Canine Pituitary-dependent Hyperadrenocorticism)

  • 김주민;황철용;윤정희;윤화영;한홍율
    • 한국임상수의학회지
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    • 제19권4호
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    • pp.455-460
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    • 2002
  • Pituitary-dependent hyperadrenocorticism (PDH) was diagnosed with history taking, physical examination, complete blood count, serum chemistry profiles, abdominal radiology, ultrasonography and adrenal function tests in 3 dogs. Their clinical signs were polyuria, polydipsia, polyphagia, bilateral symmetrical truncal alopecia and secondary infection in skin or urinary tract. Especially one dog showed severe clinical signs such as calcinosis cutis and delayed wound healing. These 3 dogs were diagnosed as PDH, and treated with selegiline 1-2 mg/kg /ay sid PO. 2 dogs with clinical signs of PDH were disappeared and improved, but 1 dog with severe illness progressed gradually despite of selegiline and mitotane application, and eventually died.

대구지역 굴착암석의 물리적 특성 (Physical Properties of Excavated Rocks in Taegu Area)

  • 이상호;차완용;김영수;이재호
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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    • pp.265-270
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    • 1999
  • At this study, we investigated the chemical component and the mineral granular composition of sedimentary rock and others where were distributed in Taegu area and compared correlations with each data through the various physicla and mechanical characteristic test. As the result, d and E, they are kinds of granite, which contain much albite than others were proved to be strong by mechanical tests and the correlation moduli were proved to be more than 0.8 except P wave velocity-Poisson's ration relation when examined Elastic moduluous -Poisson's ration, P, wave velocity-Uniaxial compression strength, Elastic modulous -Uniaxial compression strength and Uniaxial compression strength-Poisson's ration correlation function graph.

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세섬유 신경병증 (Small-Fiber Neuropathy)

  • 이동국
    • Annals of Clinical Neurophysiology
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    • 제5권1호
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    • pp.1-10
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    • 2003
  • Small-fiber neuropathy (SFN) is a common clinical problems. The disorder is a generalized peripheral polyneuropathy that selectively involves small-diameter myelinated and unmyelinated nerve fibers. It is often idiopathic and typically presents with painful feet in patients over the age of 60. And autoimmune mechanisms are often suspected, but rarely identified. The clinical features consisted of painful dysesthesias and postganglionic sympathetic dysfunction, as well as reduced pinprick and temperature sensation. Although affected patients complain of neuropathic pain, this condition is often difficult to diagnose because of the few objective physical signs and normal nerve conduction studies. Diagnosis of SFN is made on the basis of the clinical features, normal nerve conduction studies, and abnormal specialized tests of small fiber function. These specialized studies include assessment of epidermal nerve fiber density as well as sudomotor, quantitative sensory, and cardiovagal testing. Unless an underlying disease is identified, treatment is usually directed toward alleviation of neuropathic pain.

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공구와 칩 사이에서의 Liquid Nitrogen의 마찰 효과 (Friction on the Tool-chip Interface Under Liquid Nitrogen Cooling)

  • Jun Seong Chan
    • 대한안전경영과학회지
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    • 제4권2호
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    • pp.237-249
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    • 2002
  • A cutting fluid can improve machining quality and tool life by maintaining the tool toughness and by providing a lubrication effect to reduce the friction between the chip and tool interface. Although liquid nitrogen as an environmentally safe coolant has been widely recognized in cryogenic machining, its function as a lubricant is plausible due to its chemical inertness, physical volatility and low viscosity. Since a reduced friction is a direct witness of the lubrication effect from a tribological viewpoint, this paper presents an evaluation of the apparent friction coefficient on the tool-chip interface in cryogenic cutting operations to prove and characterize the lubricity of LN2 in cryogenic machining. The mathematical approaches have been formulated to derive the normal and frictional forces on the tool-chip interface for the oblique cutting tests.

Evaluation of Characteristics and Useful Life of Rubber Spring for Railway Vehicle

  • Woo, Chang-Su;Park, Hyun-Sung;Park, Dong-Chul
    • International Journal of Railway
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    • 제1권3호
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    • pp.122-127
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    • 2008
  • Rubber components are widely used in many application such as vibration isolators, damping, ride quality. Rubber spring is used in primary suspension system for railway vehicle. Characteristics and useful life prediction of rubber spring was very important in design procedure to assure the safety and reliability. Non-linear properties of rubber material which are described as strain energy function are important parameter to design and evaluate of rubber spring. These are determined by physical tests which are uniaxial tension, equi-biaxial tension and pure shear test. The computer simulation was executed to predict and evaluate the load capacity and stiffness for rubber spring. In order to investigate the useful life, the acceleration test were carried out. Acceleration test results changes as the threshold are used for assessment of the useful life and time to threshold value were plotted against reciprocal of absolute temperature to give the Arrhenius plot. By using the acceleration test, several useful life prediction for rubber spring were proposed.

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세탁기 도어 거동 인자 설계 최적화를 위한 시뮬레이터 및 로봇형 도어 장치 개발 (Development of Simulator and Robotic Door for Parametric Design Optimization of Washing Machine Door Motion)

  • 이준섭;정병진;문형필
    • 로봇학회논문지
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    • 제12권1호
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    • pp.19-25
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    • 2017
  • A design methodology for parametric design optimization of washing machine door is presented. We develop a motion simulator and a robotic door to simulate the various motion of washing machine doors. The motion of the washing machine door is related to hinge parameters. Springs and dampers are usually used in the hinge of washing machine door for controlling motion of the door. A physical simulator of the door motion is used for finding candidate parameters of the hinge and a robotic door whose motion is controlled algorithmically is used for consumer tests. Through the consumer evaluation on the robotic motion, the optimized parameters are determined. We find the optimal parameters as a function of angle and angular velocity of the door.

가변 프레임 구조를 지원하는 국경 감시/정찰용 통신 단말 및 프레임 구조 가변 방법 (Border Guard/Reconnaissance Communication Terminal for Providing Variable Frame Structure and Method for Altering the Frame Structure)

  • 김장훈;한철희;서봉용
    • 한국군사과학기술학회지
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    • 제19권1호
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    • pp.50-56
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    • 2016
  • This paper is about the implementation of the OFDM-based border guard/reconnaissance communication terminal systems. We have implemented Real-time Dynamic DL/UL symbol rate control function using the DL-MAP message, and proposed error detection method caused by malfunctioning and timing optimization method. The proposed scheme detects the variable rate symbol decoding timing without increasing additional physical layer logic, and also provides a wide variety of DL/UL data transfer rate. Furthermore, the proposed scheme applies to the current border guard/reconnaissance equipment and confirms a operation performance through field tests and demonstration at home and abroad.

Processing of dynamic wind pressure loads for temporal simulations

  • Hemon, Pascal
    • Wind and Structures
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    • 제21권4호
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    • pp.425-442
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    • 2015
  • This paper discusses the processing of the wind loads measured in wind tunnel tests by means of multi-channel pressure scanners, in order to compute the response of 3D structures to atmospheric turbulence in the time domain. Data compression and the resulting computational savings are still a challenge in industrial contexts due to the multiple trial configurations during the construction stages. The advantage and robustness of the bi-orthogonal decomposition (BOD) is demonstrated through an example, a sail glass of the Fondation Louis Vuitton, independently from any tentative physical interpretation of the spatio-temporal decomposition terms. We show however that the energy criterion for the BOD has to be more rigorous than commonly admitted. We find a level of 99.95 % to be necessary in order to recover the extreme values of the loads. Moreover, frequency limitations of wind tunnel experiments are sometimes encountered in passing from the scaled model to the full scale structure. These can be alleviated using a spectral extension of the temporal function terms of the BOD.

노년기 우울증에서 혈관성 위험인자와 아포지단백 E4의 상호작용 (Interactions of Vascular Risk Factors and Apolipoprotein E4 on Geriatric Depression)

  • 박혜영;김재민;신일선;양수진;김성완;김선영;신희영;윤진상
    • 생물정신의학
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    • 제13권2호
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    • pp.103-109
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    • 2006
  • Objective : Associations of vascular risk/disease or apolipoprotein E ${\varepsilon}4$(APOE4) with geriatric depression has been unclear at a population level. This study aimed to evaluate whether there would be interactions of vascular risk/disease and APOE4 on depression in a Korean elderly population. Methods : 732 community residents aged 65 or over were assessed for depression(GMS), information on vascular risk/disease(reported stroke, transient ishemic attack, heart disease, hypertension, diabetes, smoking), examinations for vascular risk/disease(blood pressure, blood tests for glucose and lipid profiles, body size), APOE genotypes, demographic characteristics(age, gender, education), physical health, and cognitive function(MMSE). Results : Previous stroke and lower level of high density lipoprotein(HDL) cholesterol were significantly associated with geriatric depression independent of demographic characteristics, physical illnesses, and cognitive function. These associations were statistically significant only in those with APOE4, although the interaction terms didn't reach to statistical significance. Conclusion : Associations between vascular risk/disease and geriatric depression might be more prominent in those with APOE4. However further research would be needed to clarify this issue.

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