• Title/Summary/Keyword: PSD analysis

Search Result 261, Processing Time 0.031 seconds

Verification of Long-distance Vision-based Displacement Measurement System (장거리 영상기반 변위계측 시스템 검증)

  • Kim, Hong-Jin;Heo, Suk-Jae;Shin, Seung-Hoon
    • Journal of the Regional Association of Architectural Institute of Korea
    • /
    • v.20 no.6
    • /
    • pp.47-54
    • /
    • 2018
  • The purpose of this study is to verify the long - range measurement performance for practical field application of VDMS. The reliability of the VDMS was verified by comparison with the existing monitoring sensor, GPS, Accelerometer and LDS. It showed the ability to accurately measure the dynamic displacement by tracking a motion of free vibration of target. And using the PSD function of measured data, the results in the frequency domain were also analyzed. We judged that VDMS is able to identify the higher system mode and has sufficient reliability. Based on the reliability verification, we conducted tests for long-distance applicability for actual application of VDMS. The distance from the stationary target model structure was increased by 50m interval, and the maximum distance was set to 400m. From the distance of 150m, the image obtained by the commercial camcorder has an error in the analysis, so the measured displacement comparison was performed between the LDS and the refractor telescope measurement results. In the measurement results of the displacement area of VDMS, the data validity was deteriorated due to the data shift by the external force and the quality degradation of the enlarged image. However, even under the condition that the effectiveness of the displacement measurement data of VDMS is low, the first mode characteristic included in the free vibration of the object is clearly measured. If the influence from the external environment is controlled and stable data is collected, It is judged that reliability of long-distance VDMS can be secured.

Design of an electrostatic 2-axis MEMS stage with large area platform (대면적 플랫폼을 갖는 정전형 2 축 MEMS 스테이지의 설계)

  • 정일진;전종업;백경록;박규열
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2004.10a
    • /
    • pp.373-378
    • /
    • 2004
  • Recently the electrostatic 2-axis MEMS stages have been fabricated for the purpose of an application to PSD (Probebased Storage Device). However, most of them have low area efficiency, which is undesirable as data storage devices, since all of the components (springs, comb electrodes, anchors, platform, etc.) are placed in-plane. In this paper, we present a novel structure of electrostatic 2-axis MEMS stage that is characterized by having large area platform. For large area efficiency, the actuator part consisting of mainly comb electrodes and springs is placed right below the platform. In this article, the structures and operational principle of the MEMS stages are described, followed by design procedure, structural and modal analysis using FEM(Finite Element Method). The area efficiency of the MEMS stage was designed to be about 55%, that is very large compared with conventional ones having a few percentage.

  • PDF

PSD on the Characteristic of Heart Rate Variability of patients with Vasovagal Syncope by Complex Demodulation Method (CDM 방법에 의한 실신 환자의 심박동수 변화율의 PSD 특성에 관한 연구)

  • Choi, Kyu-Sub;Lee, Joon-Young;Kim, Dong-Chul;Yoon, Sung-Won;Lee, Myoung-Ho
    • Proceedings of the KIEE Conference
    • /
    • 2000.11d
    • /
    • pp.854-856
    • /
    • 2000
  • In this paper, complex demodulation method to access the dynamic autonomic nervous system characteristic of patients with syncope is proposed. Assessment of heart rate variability using conventional power spectral analysis such as FFT or AR-modeling could not capture a split change occurrence. However, in this paper, these changes are seen and by using Complex Demodulation Method(CDM) autonomic nervous system function assessments of patients with vasovagal syncope were verified and suggested.

  • PDF

Application of Malononitrile Derivatization Method for Structural Glycomics Study in Matrix-assisted Laser Desorption/Ionization Time-of-flight Mass Spectrometry

  • Ahn, Yeong-Hee;Yoo, Jong-Shin
    • Journal of Photoscience
    • /
    • v.8 no.2
    • /
    • pp.83-86
    • /
    • 2001
  • Structural analyses of oligosaccharide-malononitrile derivatives were conducted by matrix-assisted laser desorption/ionization post-source decay (MALDI-PSD) analysis in positive ion mode. The malononitrile derivatives of oligosaccharides, which were developed for highly sensitive detection of multi-component oligosaccharides by negative ion electrospray ionization mass spectrometry (ESI MS), were detected by positive-ion MALDI with the detection limit of 2 pmol level from the crude derivatization sample. The used matrix affected drastically the analytical results of oligosaccharide-malononitrile derivative by matrix-assisted laser desoprtion/ionization mass spectrometry (MALDI MS). The malononitrile derivatization of oligosaccharide also affect the patterns of MALDI-PSD spectra and give much more structural information than the free oligosaccharide.

  • PDF

Generation of Road Surface Profiles with a Power Spectral Density Function (전력밀도함수를 이용한 노면형상 생성에 관한 연구)

  • 김광석;유완석
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.5 no.1
    • /
    • pp.136-145
    • /
    • 1997
  • To analyzed ride quality and to predict durability in vehicle dynamics, it is essential to describe a road surface profile precisely. This paper presents a technique to generate road surface profiles in a spatial domain by using a power spectral density function. A single track power spectral density function is proposed to describe a road surface profile, which is also applicable for multi-track vehicle response analysis, The derived road surfaces are compared to ISO(International Organization for Standardization) standards and classifications, proposed by the MIRA(Motor Industry Research Association). The methodology in this paper is also proposed to generate road roughness description with a limited external data. A small amount of external curve data is combined with an internal PSD function to generate road surface roughness in a spatial domain.

  • PDF

Analysis of internal-type ultra-high frequency partial discharge sensor for gas-insulated switch gear (GIS) using 3-D electromagnetic simulator (3차원 전자기장 모사를 이용한 가스절연개폐장치(GIS) 내장형 극초단파 부분방전 센서의 특성 평가)

  • Park, Ki-Jun;Goo, Sun-Geun;Yoon, Jin-Yul;Lee, Young-Sang;Choi, Gil-Soo
    • Proceedings of the KIEE Conference
    • /
    • 2003.07c
    • /
    • pp.1843-1844
    • /
    • 2003
  • 154 kV급 가스절연개폐장치(GIS)용dp 장착할 수 있는 내장형 극초단파 (UHF) 부분방전(PD) 센서의 고주파 특성을 전산모사 하였다. UHF PD 센서는 일종의 광대역 안테나이므로 3차원 전자기장 해석도구를 활용하여 주파수 또는 시간 영역에서 고주파특성을 해석하였다. 센서의 구조를 결정하는 센서장착용 구멍과 센서의 크기를 변수로 조절하면서 내장형 UHF PD 센서의 특성을 해석 하였다. 센서가 장착되는 구멍의 크기와 센서의 구조변화에 따라 반사손실이 변화하였으며 GIS의 전파 mode의 영향을 받는다.

  • PDF

Improved Mechanical Fault Identification of an Induction Motor Using Teager-Kaiser Energy Operator

  • Agrawal, Sudhir;Giri, V.K.
    • Journal of Electrical Engineering and Technology
    • /
    • v.12 no.5
    • /
    • pp.1955-1962
    • /
    • 2017
  • Induction motors are a workhorse for the industry. The condition monitoring and fault analysis are the main concern for the engineers. The bearing is one of the vital segment of the induction machine and the condition of the whole machine is decided based on the condition of the bearing. In the present paper, the vibration signal of the bearing has been used for the analysis. The first line of action is to perform a statistical analysis of the vibration signal which gives trends in signal. To get the location of a fault in the bearing the second action is to develop an index based on Wavelet Packet Transform node energy named as Bearing Damage Index (BDI). Further, Teager-Kaiser Energy Operator (TKEO) has been calculated from higher index value to get the envelope and finally Power Spectral Density (PSD) has been applied to identify the fault frequencies. A performance index has also been developed to compare the usefulness of the proposed method with other existing methods. The result shows that the strong amplitude of fault characteristics and its side bands help to decide the type of fault present in the recorded signal obtained from the bearing.

Analysis on the Impact of UWB Sensor on Broadband Wireless Communication System (UWB 센서에 의한 광대역 무선 시스템의 간섭 영향 분석)

  • Cheng, Yan-Ming;Lee, Il-Kyoo;Lee, Yong-Woo;Oh, Seung-Hyeub;Cha, Jae-Sang
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.10 no.3
    • /
    • pp.83-89
    • /
    • 2010
  • This paper presents the impacts of Ultra Wide-Band(UWB) sensor using frequency of 4.5 GHz on Broadband Wireless communication system which uses frequency of 4.5 GHz. The Minimum Coupling Loss (MCL) method and Spectrum Engineering Advanced Monte Carlo Analysis Tool (SEAMCAT) is used to evaluate the interference effects of UWB sensor on Broadband Wireless communication system, respectively. The minimum protection distance between single UWB sensor and mobile station of Broadband Wireless communication system should be more than 1.2 m to guarantee the co-existence. In case of multiple UWB sensors, UWB transmitting PSD of around -68.5 dBm/MHz below should be required to guarantee interference probability of 5% below for mobile station of Broadband Wireless communication system.

Developmental Expression of Neurofilament 3 (NF-M) in the Cultured Rat Cortical Neurons (배양한 흰쥐 대뇌신경세포에서 신경미세섬유 3(NF-M)의 발생학적 표현)

  • Jung Jae-Seob;Cho Sun-Jung;Jin IngNyol;Jung Seung Hyun;Moon Il Soo
    • Journal of Life Science
    • /
    • v.15 no.4 s.71
    • /
    • pp.600-606
    • /
    • 2005
  • Neurofilament (NF) proteins constitute the major intermediate filament type in adult neurons. They are made up by the copolymerization of the neurofilament light (NF-L, 61 kDa), medium (NF-M, 90kDa), and heavy (NF-H, 115 kDa) proteins. Although neurofilaments play a crucial .ole in neuronal growth, organization, shape, and plasticity, their expression pattern and cellular distribution in the developing neurons remain unknown. In this study, we have produced a rabbit polyclonal antibody specific to NF-M and investigated expression of NF-M in cultured cortical neurons. Immunostaining of 12 and 24 h cultures revealed strong expression of NF-M in axonal growth cone and in the region of a soma toward the axon. Doublestaining of 4 and 14 DIV corical neurons with NF-M and PSD95 antibodies revealed that both axon and dendrites were stained intensely with NF-M antibody, and that NF-M immunostaining along dendrites is often punctate and colocalize with PSD95 puncta, indicating that the puncta represent postsynaptic spines. Presence of NF-M in the postsynaptic spine was also indicated by immunoblot analysis of the postsynaptic density fraction. Taken together, our results show intensive targeting of NF-M into axons in the early axonal development, and into spines in mature neurons, indicating its important functions in axon and spine development.