• Title/Summary/Keyword: rotational measure

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Effects of Linear and Nonlinear Shear Deformation on Measurement for Stickiness of Cosmetics Using Rotational Rheometer

  • Bae, Jung-Eun;Ryoo, Joo-Yeon;Kang, Nae-Gyu
    • Korea Journal of Cosmetic Science
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    • v.2 no.1
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    • pp.33-46
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    • 2020
  • Cosmetics are representative complex fluids, and there have been many studies focusing on the correlation between the rheological properties and sensory attributes. Various instrumental measurements have been suggested to evaluate the sensory attributes, and one of the most common instruments is Texture Analyzer (TA). Although it is reported that the adhesiveness measured by TA is related to the stickiness of cosmetics, there exists reproducibility problem because measurements with TA are sensitive to application conditions. In this study, an instrumental protocol using rotational rheometer has been set up to measure the stickiness of cosmetics. This protocol consists of two steps. The first step is a preconditioning step, and various types of shear deformations are applied to the samples. The next step is the extensional flow and the axial force is measured. When the amplitude of the shear flow corresponded to the linear viscoelastic region, the axial force is the same as those without preconditioning. On the other hand, an axial force decreases as variation nonlinearity increases. It is because the effects of microstructure changes caused by nonlinear deformation affects the extensional flow. It is worth noting that a new protocol facilitates to evaluate the stickiness of cosmetics in a more systematic way.

Sensor Module for Detecting Postural Change and Falls

  • Jeon, G.R.;Ahn, S.J.;Shin, B.J.;Kang, S.C.;Kim, J.H.
    • Journal of Sensor Science and Technology
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    • v.23 no.6
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    • pp.362-367
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    • 2014
  • In this study, a postural change detection sensor module (PCDSM) was developed to detect postural changes in activities of daily living (ADL) and falls. The PCDSM consists of eight mercury sensors that measure angle variations in $360^{\circ}$ rotation and $90^{\circ}$ tilting. From the preliminary study, the output characteristics of the PCDSM were confirmed with the angle variations of rotational motion and a tilting table. Three experiments were conducted to test rotational motion, postural changes, and falling and lying. The results confirmed that the PCDSM could effectively detect postural changes, movement patterns, and falls or non-falls.

3 Directional Vibration Measurement of Wide Face Width Helical Gears (광치폭 헬리컬 기어의 3 방향 진동 측정)

  • Park, Chan-Il;Cho, Do-Hyun
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.661-666
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    • 2004
  • The purpose of this study is to measure the rotational vibration, radial vibration, and axial vibration for the helical gear with the wide face width relative to the whole depth. For this purpose, the experimental apparatus is designed and manufactured. The gear vibration of each direction is measured by the accelerometers attached at the gear body. As a result, meshing frequency and second harmonic component are greatly contributed to the gear vibration. As the rotational speed is increased, meshing frequency component has the more significant peak than the second harmonic one. However, the doubled torque decreases the vibration magnitude on the contrary and changes order of the vibration magnitude in each direction.

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Turbulent properties in a mixed statistically stationary flow

  • Baek, Tae-Sil;Doh, Deog-Hee
    • Journal of Advanced Marine Engineering and Technology
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    • v.37 no.7
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    • pp.729-736
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    • 2013
  • The turbulent properties in a mixed statistically stationary flow were investigated experimentally by a pseudo stereoscopic PIV. In order to validate the experimental results, the profiles of the turbulent kinetic energy were evaluated with the flow features. A mechanical agitator having 6 blades was installed at the bottom of the mixing tank (D=60cm, H=60cm). The agitator was rotated with 80rpm clockwise and counter-clockwise. For the measurements, three cameras were used and all were synchronized. The images captured by one of the three cameras was used for the measurement of rotational speed, and the images captured by the other two cameras were used to measure three dimensional components of velocity vectors. All vectors captured at the same rotational angle were phase averaged to construct three-dimensional vector fields to reconstruct the spatial distribution of the flow properties. It was seen that the jet scrolling along the tank was the main source of mixing.

Performance Measurement of the Eddy Current Heat Generator with Different Array of Permanent Magnets (서로 다른 자석 배열을 가지는 와전류 열원화 장치의 성능 측정)

  • Yun, Teak-Han;Son, Young-Woo;Lee, Jang-Ho
    • New & Renewable Energy
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    • v.9 no.1
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    • pp.17-24
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    • 2013
  • Eddy Current is one of ways to make heat using rotational energy of wind turbine rotor. Four difference arrays of permanent magnets around rotor surface are used to generate heat using eddy current in this study. For the evaluation of heating performance, new test rig is prepared to measure water flow and temperatures in the inlet and outlet of the eddy current heat generator. In the test, torque and rotational speed are also measured in the motor driven system, and evaluated if the torque is matched with it of wind turbine rotor or not. It will be shown that the eddy current heat generator can be applied to real urban wind energy systems in this study.

Experimentally Measured Rotational Reorientation Time of Coumarin 6 Laser Dye in Ethanol and Acetonitrile Solvents

  • Renuka, C.G.;Raikar, U.S.
    • Journal of Photoscience
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    • v.12 no.3
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    • pp.119-122
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    • 2005
  • The photophysical properties of coumarin 6 laser dye have been studied in two solvents; ethanol and acetonitrile using steady-state fluorescence depolarization technique. The experimentally measured reorientation time of coumarin 6 is more or less the same in given solvents at particular temperature. It is found that coumarin 6 rotates slower in acetonitrile than in ethanol especially at higher values of viscosity over temperature. We also measure the ground and excited state dipole moments of coumarin 6 by solvent perturbation method. The results found that excited state dipole moment is greater than ground state dipole moment, which indicates that excited state is more polar than the ground state.

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Reliability Evaluation for Hinge of Folder Devices Using ESPI

  • Kyungyoung Jhang;Minkwan Hyun;Lee, Taehun;Seokwon Chang
    • International Journal of Reliability and Applications
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    • v.5 no.1
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    • pp.15-24
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    • 2004
  • Folder type electronic devices have hinge to support the rotational motion of folder. This hinge is stressed by the rotational inertia moment of folder at the maximum open limit position of folder. This stress is repeated whenever the folder is open, and it is a cause of hinge fracture. In this paper, the reliability evaluation for the hinge fracture in the folder type cellular phone is discussed. For this, the durability testing machine using crank-rocker mechanism is developed to evaluate the life cycle of the hinge, and the degradation after repetitions of opening and shutting is evaluated from the deformation around the hinge, where the deformation is measured by ESPI (electronic speckle pattern interferometer). Experimental results showed that ESPI was able to measure the deformation of hinge precisely, so we could monitor the change of deformation around the hinge as the repetition number of folder open is increased.

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Estimation of transformation parameters using shape matching (형상 정합을 통한 변환 파라미터 추출)

  • 박용희;전병호;김태균
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.7
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    • pp.1523-1533
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    • 1997
  • Image registration is concerned with the establishment of correspondence between images of the same scene with translational, rotational, and scaling differences. The estimated transformation parameters between images are very important information in the field of many applications. In this paper, we propose a shape matching scheme for finding correspondence points for images with various differences, Tranditional solutions to this area are unreliable for the rotational and schaling changes between images, and the feature extraction of partially occluded scene. To solve those problems, dominant points on digital curves are detected by scale-space filtering, and initial matching is performed by similarity measure of cumulative curvatures for dominant points. For initial matching segments pairs, optimal matching points are calculated using dynamic programming.Finally, transformation parameters are estimated.

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Feasibility Verification of a Non-Contact Vibration Sensor for Rotating Shafts Endowed with Rotational-Encoder Capability (회전속도 측정기능을 갖춘 비접촉 축 진동센서의 가능성 검증)

  • Lee, Ho-Cheol;Kim, Myong-Ho;Park, Jung-Yang
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.30 no.12 s.255
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    • pp.1596-1602
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    • 2006
  • In this paper, a hybrid sensor is proposed that has two capabilities: the first is to sense longitudinal or flexural transient vibration signals selectively which are transmitted along the target shaft, and the second to measure the rotating speed of the shaft. All measurements are made in a non-contact manner since this sensor uses magnetostriction as its measuring principle. The signal selection between two vibration modes requires only electrical switching operations and the switching between these two sensing capabilities-vibrations and rotational speed-are accomplished by a very simple mechanical operation. To verify the capabilities of the proposed sensor, a prototype sensor is fabricated and the experiments are made. The results show this sensor can embody two sensing capabilities in one sensor configuration.

New Carotid Artery Stenosis Measurement Method Using MRA Images (경동맥 MRA 영상을 이용한 새로운 내경 측정 방법)

  • 김도연;박종원
    • Journal of KIISE:Software and Applications
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    • v.30 no.12
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    • pp.1247-1254
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    • 2003
  • Currently. the north american symptomatic carotid endarterectomy trial, european carotid surgery trial, and common carotid method are used to measure the carotid stenosis for determining candidate for carotid endarterectomy using the projection angiography from different modalities such as digital subtraction angiography. rotational angiography, computed tomography angiography and magnetic resonance angiography. A new computerized carotid stenosis measuring system was developed using MR angiography axial image to overcome the drawbacks of conventional carotid stenosis measuring methods, to reduce the variability of inter-observer and intra-observer. The gray-level thresholding is one of the most popular and efficient method for image segmentation. We segmented the carotid artery and lumen from three-dimensional time-of-flight MRA axial image using gray-level thresholding technique. Using the measured intima-media thickness value of common carotid artery for each cases, we separated carotid artery wall from the segmented carotid artery region. After that, the regions of segmented carotid without artery wall were divided into region of blood flow and plaque. The calculation of carotid stenosis degree was performed as the following; carotid stenosis grading is(area measure of plaque/area measure of blood flow region and plaque) * 100%.