• 제목/요약/키워드: concept testing

검색결과 383건 처리시간 0.027초

가상시험법을 이용한 알루미늄 너클의 내구수명 평가 (Durability Performance Evaluation of an Aluminum Knuckle using Virtual Testing Method)

  • 고한영;최규재
    • 한국자동차공학회논문집
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    • 제18권1호
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    • pp.44-50
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    • 2010
  • Durability performance evaluation technology using Virtual Testing Method is a new concept of a vehicle design, which can reduce the automotive components design period and cost. In this paper, the fatigue life of an aluminum knuckle of a passenger car is evaluated using virtual testing method. The flexible multibody dynamic model of a front half car module is generated and solved with service loads which are measured from Belgian roads. Using a multibody dynamic analysis software, the flexible multibody dynamic simulation of a half car model is carried out and the dynamic stress profile of an aluminum knuckle is acquired. The stress profile is exported to a fatigue analysis software and durability performance of an aluminum knuckle is evaluated.

Testing of rubber bearings for the dynamic damper of seismic isolated buildings

  • Melkumyan, Mikayel;Hakobyan, Alexander
    • Smart Structures and Systems
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    • 제2권4호
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    • pp.321-328
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    • 2006
  • The paper describes the testing facilities and the methodology on testing of laminated rubber bearings envisaged for application in the system of Dynamic Damper (DD) of seismic isolated buildings, as well as the obtained results. For the first time in Armenia laminated rubber bearings were tested simultaneously under the action of horizontal shear force and vertical tension force. The test results have proven the possibility of using rubber bearings as elements subjected to tension due to action of the mass of DD. Also it was confirmed that the suggested structural concept of DD for reducing the displacements and shear forces of seismic isolation systems will have reliable behavior during the design level earthquakes.

A Study on Bayesian p-values

  • Hwnag, Hyungtae;Oh, Heejung
    • Communications for Statistical Applications and Methods
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    • 제9권3호
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    • pp.725-732
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    • 2002
  • P-values are often perceived as measurements of degree of compatibility between the current data and the hypothesized model. In this paper, a new concept of Bayesian p-values is proposed and studied under the non-informative prior distributions, which can be thought as the Bayesian counterparts of the classical p-values in the sense of using the concept of significance level. The performances of the proposed Bayesian p-values are compared with those of the classical p-values through several examples.

Simulation study of magnetorheological testing cell design by incorporating all basic operating modes

  • Mughni, Mohd J.;Mazlan, Saiful A.;Zamzuri, Hairi;Yazid, Izyan I.M.;Rahman, Mohd A.A.
    • Smart Structures and Systems
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    • 제14권5호
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    • pp.901-916
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    • 2014
  • Magnetorheological (MR) fluid is one of the field-responsive fluids that is of interest to many researchers due to its high yield stress value, which depends on the magnetic field strength. Similar to electrorheological (ER) fluid, the combination of working modes is one of the techniques to increase the performance of the fluids with limited focus on MR fluids. In this paper, a novel MR testing cell incorporated with valve, shear and squeeze operational modes is designed and constructed in order to investigate the behaviour of MR fluid in combined mode. The magnetic field distribution in the design concept was analyzed using finite element method in order to verify the effective areas of each mode have the acceptable range of flux density. The annular gap of valve and shear were fixed at 1 mm, while the squeeze gap between the parallel circular surfaces was varied up to 20 mm. Three different coil configurations, which were made up from 23 SWG copper wires were set up in the MR cell. The simulation results indicated that the magnetic field distributed in the squeeze gap was the highest among the other gaps with all coils were subjected to a constant applied current of 1 A. Moreover, the magnetic flux densities in all gaps were in a good range of magnitude based on the simulations that validated the proposed design concept. Hence, the 3D model of the MR testing cell was designed using Solidworks for manufacturing processes.

The Development of the Components of the Length Measurement Concept in the Procedure of Measurement Using a Ruler

  • Antic, Milica D.;Dokic, Olivera J.
    • 한국수학교육학회지시리즈D:수학교육연구
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    • 제22권4호
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    • pp.261-282
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    • 2019
  • The research related to testing pupils' achievement in the field of Measurement and Measure in initial teaching of geometry points to an insufficient adoption of the basic components of the length measurement concept among pupils. In order to discover the cause, we looked at the basic components on which the procedure of measuring length using a ruler is based, highlighted the possibilities of introducing the procedure in measuring length, and determined pupils' achievement during the procedure of measuring length using a ruler. The research sample consisted of 145 pupils, out of which 72 were the 2nd grade pupils and 73 were the 4th grade pupils. A descriptive method was applied in the research. The technique we used was testing, and for the statistical data processing we used a χ2 test. The results of the research show that, when drawing a straight line of a given length using a ruler, there is no statistical difference in achievement between the 2nd and 4th grade pupils, nor in the pupils' knowledge regarding drawing a ruler independently, while drawing a straight line of a given length using a "broken" ruler 4th grade pupils are statistically better. The results of the research indicate that pupils' achievement is better in doing standard tasks than in non-standard ones, given that the latter require conceptual knowledge. The components of the concept of length measurement using ruler have not been sufficiently developed yet, and these include: zero-point, partitioning a measured object in a series of consecutive measurement units and their iteration. We shed more light on the critical stage in the procedure of length measurement - the transition from non-standard to standard units and the formation of the length measurement scale. For further research, we propose to look at the formation of the concept of length measurement using the ruler through all its components and their inclusion in the mathematics curriculum, as well as examining the correlation of pupils' achievement in the procedure of measuring length with their achievement in measuring area (and volume).

적외선 열화상을 이용한 비파괴시험 활용 및 결함 진단 (The Utilization of Nondestructive Testing and Defects Diagnosis using Infrared Thermography)

  • 최만용;김원태
    • 비파괴검사학회지
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    • 제24권5호
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    • pp.525-531
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    • 2004
  • 본 고는 적외선 열화상의 개념과 적외선열화상 측정윈리 및 카메라 셋팅을 기술하고 적외선열화강(IRT)에 의한 비파괴검사(NDT)의 활용 및 비파괴검사의 진단에 대하여 살펴보았다. 적외선 열화상은 주어진 표면을 따라 온도에 관련된 열패턴의 평가를 통한 정기적인 비접촉, 비파괴 시험의 수행으로 초기에 장비 고장의 예방이 가능하다. 진단 활용으로서, 열적으로 가열된 내부결함이 있는 블록에 대하여 적외선열화상을 이용한 열화상 패턴을 비파괴 기법으로 평가하고, 결함과 열화상패턴간의 특성을 분석하여 열화상 평가 기법에 대하여 논하였다.

Performance Testing of Composite Web-Service with Aspect-Based WS-BPEL Extension

  • Kim, Jong-Phil;Sung, Dong-Hyuk;Hong, Jang-Eui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제5권10호
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    • pp.1841-1861
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    • 2011
  • The advance in Service-Oriented Architecture (SOA) and web services has led to the development of new types of a system in which heterogeneous service components can connect and compose to solve a complex business problem. In the SOA, even though these service components are valid in their functionality, there is a need to test their behaviors when those services are composited. In recent years, WS-BPEL has received a wide acceptance as a means of integrating distributed service components. To test the composite service, the existing testing techniques have been focused on the functional features based on the WS-BPEL process. However as SOA approach is applying to real-time software development, the performance of composite service becomes one of important issues. This paper proposes a technique to the performance testing of a composite service with WS-BPEL extension which combined with the concept of aspect. Our WS-BPEL extension has been made towards annotating aspect component which is measuring the response time of the composite service. This paper also explains the procedure of performance testing with on-line transaction system. Our technique can apply to choose an adequate component in service composition with considering the performance among several candidate web service components.

열충격시험을 통한 LED 박리 평가법에 관한 연구 (LED Delamination Evaluating Method by Thermal Shock Test)

  • 장인혁;한지훈;고민지;이영주;임홍우
    • 공학기술논문지
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    • 제6권2호
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    • pp.121-124
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    • 2013
  • This paper proposed a new concept of estimating method for LED(light-emitting diode) delamination with high accuracy. Usually, The LED is composed several materials which are LED chips, gold wire, phosphor, epoxy resin, adhesive, reflector and lead frame. These different materials are usually delaminated in a trouble conditions which are huge temperature difference, hot and humid or mechanical shocked. When the components are delaminated, a luminance will be lost, moisture be absorbed easily and a thermal resistance be increased attendantly. As a conventional method to estimate a delamination of LEDs, a solution immersing method is usually used in a field of LED manufacturing companies or researching institutes. This method has an advantage of simplicity but it is only shown that the existence of delamination or not. In this paper, we have proposed an estimating method for LEDs delamination using the polishing and the electron microscope. New proposed method has shown the result of confirming delamination without destruction and enabled quantitative analysis for LED delamination.

Preimplantation genetic testing for aneuploidy: The management of mosaic embryos

  • Yu, Eun Jeong;Kim, Min Jee;Park, Eun A;Kang, Inn Soo
    • Clinical and Experimental Reproductive Medicine
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    • 제49권3호
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    • pp.159-167
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    • 2022
  • As the resolution and accuracy of diagnostic techniques for preimplantation genetic testing for aneuploidy (PGT-A) are improving, more mosaic embryos are being identified. Several studies have provided evidence that mosaic embryos have reproductive potential for implantation and healthy live birth. Notably, mosaic embryos with less than 50% aneuploidy have yielded a live birth rate similar to euploid embryos. This concept has led to a major shift in current PGT-A practice, but further evidence and theoretically relevant data are required. Proper guidelines for selecting mosaic embryos suitable for transfer will reduce the number of discarded embryos and increase the chances of successful embryo transfer. We present an updated review of clinical outcomes and practice recommendations for the transfer of mosaic embryos using PGT-A.