• Title/Summary/Keyword: quantitative variation

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Spike Variable Analysis of Surface EMG Signal During Constant Voluntary Contraction (일정한 자의 수축 시 표면 근전도 신호에 대한 Spike 변수 해석)

  • Yang, Hee-Won;Joung, Eui-Kon;Lee, Jin
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.4
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    • pp.809-816
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    • 2007
  • This paper presents an analysis of the SEMG signal quantitatively and automatically using spike variables : MSF, MSA, MSS, and MSD. The SEMG signals were recorded in three muscle parts, first dorsal interosseus, biceps brachii and abductor policis brevis, from 14 normal subjects. Emphasis was placed on the following 3 points in the experiments. 1) Suggest proper window length to estimate the spike variables 2) Investigate variation of the spike variables to varying %MVC. 3) Investigate variation of the spike variables to the sustained contraction for 30 minutes. Quantitative results were showed and examined in point of practical clinical application.

Long-term Variability of Sea Surface Temperature in the East China Sea: A Review (동중국해 표층수온의 장기 변동성: 종설)

  • Lee, Jae Hak;Kim, Cheol-Ho
    • Ocean and Polar Research
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    • v.35 no.2
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    • pp.171-179
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    • 2013
  • The long-term variability of sea surface temperature in the East China Sea was reviewed based mainly on published literatures. Though the quantitative results are not the same, it is generally shown that sea surface temperature is increasing especially in recent years with the rate of increase about $0.03^{\circ}C$/year. Other meaningful results presented in the literatures is that the difference of water properties between layers upper and lower than the thermocline in summer shows an increasing trend both in temperature and salinity, suggesting that the stratification has been intensified. As a mechanism by which to evaluate the wintertime warming trend in the region, the weakening of wind strength, which is related to the variation of sea level pressure and atmospheric circulation in the western North Pacific and northern Asian continent, is suggested in the most of related studies.

Optical Error Analyses in AQuaKET - Intensity variation, Diffraction, and Parallax

  • Kim, Young-Soo
    • Bulletin of the Korean Space Science Society
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    • 2003.10a
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    • pp.27-27
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    • 2003
  • The Automated Quantitative Knife-Edge Test (AQuaKET) method was developed for testing the surface profiles of large optics with high accuracy. Testing with the required accuracy of very large telescope is not an easy job to achieve, as it is a nano-technology. There are lots of possible error sources which can occur during the measurements and in the data processing of the AQuaKET. The error sources can be categorized into 5 areas: optics, mechanics, electronics, numerical processes, and system. In this paper, possible error sources in Optics are discussed, which are intensity variation of the light source, diffraction effects, and parallax effect. In this talk, those possible error sources in optics are presented and discussed.

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A Study on Temperature Features of Broadband Ultrasonic Attenuation (초음파 광역 감쇠의 온도 특성에 관한 연구)

  • 신정식;안중환;한승무;김형준
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.10a
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    • pp.245-248
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    • 1997
  • The distilled water is used for the ultrasonic wave propagating material in the measurements of broadband ultrasonic attenuation (BUA) that is applied in industrial and medical applications, The acoustic impedance of water is significantly changed with its temperature. Therefore, the quantitative evaluation of BUA with temperature and the ultrasonic wave propagating distance is highly needed. In this study, we evaluated the variation of attenuation with change in temperature. To measure the variation of BUA in the low frequency region at the temperatures, 27$^{\circ}C$, 29$^{\circ}C$, and 31$^{\circ}C$, we tested the Plyethylene, Teflon, MC-Nylon, Urethane specimens and analyzed the center frequency, frequency bandwidth, spectral peak amplitude. The results showed that BUA value appeared to be lower with increasing temperature. This may be due to the fact that the frequency feature of ultrasonic wave is affected by not only the specific gravity, acoustic impedence, but material crystalline, porosity, the distance of ultrasonic wave propagation in water.

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Study on Shape Distribution of Wear Particles with Histogram (히스토그램에 의한 마멸분의 형태분포에 관한 연구)

  • Cho, Yon-Sang;Moon, Sung-Dong;Park, Heung-Sik
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.32 no.11
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    • pp.963-969
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    • 2008
  • The wear particles are relative to the failure and the life of machine elements directly. But it is not laid down to calculate shape parameters of wear particle. To analyze a variation of distributed characteristics of wear particles on moving conditions, its shape parameters such as diameter and roundness were calculated the quantitative values by digital image processing, and had to be defined the effective method of using those data. Up to the present, the shape parameters have been used simply into the average values. But these values are not effective to analyze a variation of distributed characteristics of occurred wear particles on moving conditions. In this study, the relative histograms of shape parameters of wear particles were used for the purpose of analyzing the distribution of wear particles in various conditions. The results showed that the relative histogram of shape parameters can be effectively represented to study a wear mechanism.

Evaluation of Mechanical Characteristic of Plate-Type Polymer in Thermal-Nanoindentation Process for Hyperfine Pit Structure Fabrication (극미세 점 구조체 제작을 위한 열간나노압입공정에서 평판형 폴리머소재의 기계적 특성 평가)

  • Lee, E.K.;Lee, S.M.;Kang, C.G.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2007.10a
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    • pp.108-111
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    • 2007
  • It's important to measure quantitative properties about thermal-nano variation conduct of polymer for producing high quality components using NIL process. NanoScale indents can be used ad cells for molecular electronics and drug deliver, slots for integration into nanodevices, and defects for tailoring the structure and properties. In this study, it's to evaluate mechanical characteristic of polymer such as PMMA and PC at high temperature for manufacture of nano/micro size of polymer using indenter at high temperature. At high temperature mechanical properties of polymer have extreme variation. Because heating the polymer, it becomes softer than room temperature. In this case it is especially important to study for mechanical properties of polymer at high temperature.

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A Study on the Quantitative Analysis of Surface EMG Interference Pattern with T/A Variables (T/A 변수를 이용한 표면근전도 간섭패턴의 정량적 해석에 관한 연구)

  • Kang Won-Hee;Kim Sung-Hwan;Lee Jin
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.54 no.5
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    • pp.348-357
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    • 2005
  • We have tried to analyze the SEMG interference pattern quantitatively and automatically using T/A variables ZC, TN, mSA, mSD, UCA, AIPEA, ACT and NSS. For the analysis, we have carried out experiments on 14 SEMG interference patterns recorded from the biceps brachii, first dorsal interosseus and abductor policis brevis muscles. Emphasis was placed on the following 3 points in the experiments. 1) Suitable amplitude threshold for the automatic detection of the T/A variables. 2) Variation of the T/A variables to varying $\%$MVC. 3) Variation of the T/A variables to the sustained contraction for 30 seconds. Results of the experiments showed that T/A analysis of the SEMG interference Pattern can be effective tools for diagnostic purposes instead of the conventional NEMG method.

A Study on the Firing Reaction and Calcination Characteristics of Waste Shellfish (폐 패각류의 소성 및 하소 특성에 관한 연구)

  • Yoon, Cheol-Hun
    • Journal of the Korean Applied Science and Technology
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    • v.21 no.4
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    • pp.352-358
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    • 2004
  • The firing reaction and calcination characteristics of the waste shellfish were examined for the future use as absorbent. The weight variation was measured according to thermal-decomposition using TGA and observed variation of the phase. The qualitative and quantitative analysis of the sample were performed using XRD and the structural analysis, SEM. The results of TGA and XRD experiments showed that the almost all of the raw Corbicula Japonica and Ostrea virginjca were changed from calcite to lime by firing and calcination reaction. The result of SEM experiment showed that the plate type of the raw sample was changed to circle type, so the surface area ratio was increased. Above results suggested that waste shellfish were usable as absorbent in the viewpoint of the reuse of resource and the decrease of environmental pollution.

ATInSAR HOLOGRAM OBSERVATIONS OF COASTAL WAVE REFARCTION

  • Marghany, Maged
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.438-440
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    • 2003
  • This study is introducing a new approach of ATInSAR hologram for modeling wave refraction spectra pattern. TOPSAR data with L$_{-HH}$ and C-vv bands utilized spatial variation of wave refraction. Based on the phase information in along track interferometry, and ATInSAR hologram the quantitative information such swell wave height and spectra energy have been modeled. The phase information in ATInSAR hologram images can be transferred to wave refraction The ATInSAR hologram can be used to investigate the wave refraction pattern along the coastal waters. The fringe information pattern was shown to be useful in modeling wave refaction spectra varaition. The hologram interferometry wave refraction model consists of two sub-models. The purpose of first sub-model is to determine the swell wave height by using ATInSAR. Second sub-model aims to generate the holographic interferometry from the information of two wave spectra which detected by ATInSAR technique. The azimuth cut-off variations along the fringe patterns will be estimated. As azimuth cut-off contains the wave height information which could be used the significant wave height variation in convergence and divergence zone.

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Flow Visualization Using Thin Oil-Film in the Flow Control of Shock Wave/Turbulent Boundary-Layer Interactions (충격파와 경계층 간섭유동 제어에서 오일막을 이용한 유동가시화)

  • Lee Yeol
    • 한국가시화정보학회:학술대회논문집
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    • 2002.11a
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    • pp.117-120
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    • 2002
  • An experimental research has been carried out for flow control of the shock wave/turbulent boundary-layer interaction utilizing aeroelastic mesoflaps. Various shapes and thicknesses of the mesoflap are tested to achieve different deflections of the flap, and ail the results are compared to the solid-wall reference case without flow-control mechanism. Quantitative variation of skin friction has been measured downstream of the interactions using the laser interferometer skin friction meter, and qualitative skin friction distribution has been obtained by observing the interference fringe pattern on the oil-film surface. A strong spanwise variation in the fringe patterns with a narrow region of separation near the centerline is noticed to form behind the shock structure, which phenomenon is presumed partially related to three-dimensional flow structures associated with both the sidewalls and the bottom test surface. The effect of the shape of the cavity is also observed and it is noticed that the shape of the cavity is not negligible.

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