• 제목/요약/키워드: material property identification

검색결과 30건 처리시간 0.027초

최적화 기법을 이용한 점탄성물질의 분수차 미분모델 물성계수 추정 (Identification of Fractional-derivative-model Parameters of Viscoelastic Materials Using an Optimization Technique)

  • 김선용;이두호
    • 한국소음진동공학회논문집
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    • 제16권12호
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    • pp.1192-1200
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    • 2006
  • Viscoelastic damping materials are widely used to reduce noise and vibration because of its low cost and easy implementation, for examples, on the body structure of passenger cars, air planes, electric appliances and ships. To design the damped structures, the material property such as elastic modulus and loss factor is essential information. The four-parameter fractional derivative model well describes the dynamic characteristics of the viscoelastic damping materials with respect to both frequency and temperature. However, the identification procedure of the four-parameter is very time-consuming one. In this study a new identification procedure of the four-parameters is proposed by using an FE model and a gradient-based numerical search algorithm. The identification procedure goes two sequential steps to make measured frequency response functions(FRF) coincident with simulated FRFs: the first one is a peak alignment step and the second one is an amplitude adjustment step. A numerical example shows that the proposed method is useful in identifying the viscoelastic material parameters of fractional derivative model.

최적화 기법을 이용한 점탄성물질의 유리미분모델 물성값 추정 (Identification of fractional-derivative-model parameters of viscoelastic materials using an optimization technique)

  • 김선용;이두호
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 춘계학술대회논문집
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    • pp.1235-1242
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    • 2006
  • Viscoelastic damping materials are widely used to reduce noise and vibration because of its low cost and easy implementation, for examples, on the body structure of passenger cars, air planes, electric appliances and ships. To design the damped structures, the material property such as elastic modulus and loss factor is essential information. The four-parameter fractional derivative model well describes the nonlinear dynamic characteristics of the viscoelastic damping materials with respect to both frequency and temperature with fewer parameters than conventional spring-dashpot models. However the identification procedure of the four-parameter is very time-consuming one. An efficient identification procedure of the four-parameters is proposed by using an FE model and a gradient-based numerical search algorithm. The identification procedure goes two sequential steps to make measured FRFs coincident with simulated FRFs: the first one is a peak alignment step and the second one is an amplitude adjustment. A numerical example shows that the proposed method is efficient and robust in identifying the viscoelastic material parameters of fractional derivative model.

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Model Identification of Hydraulic Pin-On-Disk type Tribotester with DDV

  • Kim, Seung-Hyun;Lee, Chang-Don;Lee, Jin-Kul
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.170.1-170
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    • 2001
  • This paper developed the model for electro hydraulic force control system by identification method via ARMAX model. Implementation of Identification is performed on Pin-On-Disk type tribotester. The wear mechanism is an important mechanic property to select a material´s life and a optimum work condition. Pin-on-disk type tribotester is popular wear analysis experimental equipment and its mechanism is that adding a force on a rotating disk to simplify two surface contact´s wear experimental condition. Material´s rotating velocity and eccentricity rotation makes disturbance and it affects adding constant force. To get a high performance of force adding part, DDV(Direct Drive Valve) which has pressure control loop is used. To obtain a tribotester´ s ARMAX model, prediction error method(PEM) is used in case force adding part and rotating part is ...

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A Wireless Identification System Using an Efficient Antenna Based on Passive Surface Acoustic Wave(SAW) Devices

  • Chang, Ki-Hun;Lee, Woo-Sung;Yoon, Young-Joong;Kim, Jae-Kwon;Park, Joo-Yong;Burm, Jin-Wook
    • Journal of electromagnetic engineering and science
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    • 제7권1호
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    • pp.12-16
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    • 2007
  • A UHF band wireless identification system based on passive surface acoustic wave(SAW) devices is presented in this paper. SAW ID tags were fabricated on Y-Z $LiNbO_3$ piezoelectric substrate with a good electro-mechanical coupling property. To reduce degradation of the antenna performance associated with the piezoelectric materials, an efficient design of the SAW RFID antenna is introduced. By measuring the parameters of the SAW ID tag, the performance of the antenna was tested by experimentation.

렌즈 구동을 위한 선형 초음파 전동기 설계 (Design of Linear Ultrasonic Motor for Small tong Actuation)

  • 권태성;이승엽;김수경
    • 정보저장시스템학회:학술대회논문집
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    • 정보저장시스템학회 2005년도 추계학술대회 논문집
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    • pp.190-194
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    • 2005
  • There is a great demand of micro-actuators for mobile information devices such as SFF optical drives and mobile camera phones. However, conventional magnetic coils of electromagnetic motors are a major obstacle for miniaturization because of their complicated structures and large power consumption. In this paper, a linear ultrasonic motor to actuate focusing lens of mobile devices is proposed. The new actuator uses a ring type bimorph piezoelectric material, and $d_{31}$ mode is adopted for applying linear motion. The interaction between inertia force and friction force makes linear motion by high-frequency saw signal input. The saw signal gives steady forces on the one direction by asymmetric inclination property of the signal itself on time domain. A commercial FEM (ANSYS) was used in this investigation for simulating structural analysis, identification of dynamic property, such as resultant displacement and coupled analysis with piezoelectric material. To evaluate the performance of the new design, a prototype was manufactured and experiments were carried out. Experimental results show the actuator motion of 1.52 mm/s at 10 kHz input signal in 5 V.

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초소형 렌즈 구동을 위한 선형 초음파 구동기 설계 (Design of a Linear Ultrasonic Actuator for Small Lens Actuation)

  • 권태성;최요한;이승엽
    • 정보저장시스템학회논문집
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    • 제2권4호
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    • pp.251-256
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    • 2006
  • There is a great demand of micro-actuators for mobile information devices such as SFF optical drives and mobile phone cameras. However, the magnetic coils used in conventional electromagnetic motors are a major obstacle for the miniaturization because of their complicated structures and large power consumption. In this paper, a linear ultrasonic motor to actuate focusing lens of mobile devices is proposed. The new actuator uses a ring type bimorph piezoelectric material, and $d_{31}$ mode is adopted for applying linear motion. The interaction between inertia force and friction force makes linear motion by high-frequency saw signal input. The saw signal gives steady forces on the one direction by asymmetric inclination property of the signal itself on time domain. A commercial FEM(ANSYS) was used in this investigation for simulating structural analysis, identification of dynamic property, such as resultant displacement and coupled analysis with piezoelectric material. To evaluate the performance of the new design, a prototype was manufactured and experiments were carried out. Experimental results show the actuator motion of 5.4 mm/s at 10V saw signal of 41 kHz.

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지적재산권 보호를 위한 전통의학 DB 구축에 관한 고찰 (Grope for a Summary Program about a Traditional Medical Database for Intellectual Property Protection in WIPO)

  • 최환수;이제현;김용진
    • 대한한의학회지
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    • 제25권3호
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    • pp.12-19
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    • 2004
  • Objectives : In the WIPO conference about the protection of intellectual property for traditional knowledge (TK) and genetic resources (GR), there was a demand concerning the necessity of recognizing the invention of TK and GR and the foundation of a related database. Methods : In the standard of the foundation of a database, the content and resource identification standards, the technological standards and the security and transmission standards were discussed. In a decision on intellectual property, it means the protection and recognition as a technology precedent of the materials of the database. Results : Massive material on traditional medical care technology in Korea has existed in many areas. However, it is hard to make a database because it is difficult to organize and find the data. In addition, a database demanded by WIPO is not only the material of images or texts of simple technology information, but also the use of patent decisions about traditional knowledge technology and the public sharing of information in related areas. A traditional medical care database would consist of the core of a subject and the related areas. The core part is the medical herb resource and Oriental clinical technology. Conclusions : These are necessary to detail the kind of medicines and prescriptions, their use, and their processing. In the related areas, it needs to detail PIAS and clinical data in regarding the industrialization. These DB have to protect the TK and the GR of Korea.

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사고대비물질 취급자의 비상대응계획 작성 프로그램 연구 (Development of a Supporting Program for the Emergency Preparedness Plan)

  • 김성범;노혜란;석광설;박재득
    • 한국안전학회지
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    • 제26권5호
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    • pp.54-58
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    • 2011
  • Emergency preparedness plan(EPP) is the systematic management of activities that involve a material degree of risk of loss or other damage to the surroundings(people, property and environment), and the boundary of accident recovery plan(ARP). The main purpose of the program is to provide a safety management system to each facility in order to enable to prevent accident and to control accident immediately. The EPP includes not only typical safety-related documentations such as material safety data sheet(MSDS), standard operation procedure(SOP), emergency response plan(ERP). EPP is established basis of the preliminary safety analysis involving risk identification, assessment and prevention plans. The program is also helpful for government or related agencies to control a number of accidents in small-scale companies in the whole country.

한약 정보 표준화를 위한 의약품 식별 표준 (IDMP) 분석 및 고찰 (Review of Identification of Medicinal Products (IDMP) Standards for Standardization of Herbal Medicine Information)

  • 김영식;김안나;이승호
    • 대한본초학회지
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    • 제37권5호
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    • pp.37-51
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    • 2022
  • Objectives : The purpose of this study was to apply informations related to herbal medicines to IDMP (Identification of Medicinal Products), an ISO standards related to medicinal products substances, for systematic collection of data through the integration of informations on distribution, manufacturing, and management of herbal medicines. Methods : By analyzing ISO 11238 and ISO/TS 19844, elements that can be used in the information model of herbal medicine were derived from the identification of medicinal products information model on substances. The labeling specified in the safety and quality control regulations for herbal medicines was mapped to the IDMP information model, and ginseng was applied as an example. Results : Herbal medicine corresponded to substance in IDMP. Among the five types of substances specified by IDMP, herbal medicines were expressed as structurally diverse. Scientific name was used as an invariant property of herbal medicine, and the substance level included information about source material and modification, and specifically included information about the scientific name, medicinal part, fraction, and processing. In addition, the specified substance level had information on the constituents, characteristic attributes, manufacturing, and grade of the herbal medicine. Conclusions : It is necessary to establish a code system for identifying herbal medicines. In order to apply the IDMP standards, research on the development of standard terms is required to express the characteristics of herbal medicines. In addition, information for identification of herbal medicines is also required, and information from production to consumption should be systematically accumulated and managed for actual application.