• Title/Summary/Keyword: PFA

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Underwater Radiated Noise Analysis for An Unmanned Underwater Vehicle Using Power Flow Analysis (파워흐름해석법을 이용한 무인잠수정의 수중방사소음해석)

  • Kwon, Hyun-Wung;Hong, Suk-Yoon;Lee, Sang-Young;Hwang, A-Rom;Song, Jee-Hun
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.22 no.4
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    • pp.328-334
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    • 2012
  • Power flow finite element method(PFFEM) combining power flow analysis(PFA) with finite element method is efficient for vibration analysis of a built-up structure, and power flow boundary element method(PFBEM) combining PFA with boundary element method is useful for predicting the noise level of a vibrating complex structure. In this paper, the coupled PFFE/PFBE method is used to investigate the vibration and radiated noise of the unmanned underwater vehicle(UUV) in water. PFFEM is employed to analyze the vibrational responses of the UUV, and PFBEM is applied to analyze the underwater radiation noise. The vibrational energy of the structure is treated as an acoustic intensity boundary condition of PFBEM to calculate underwater radiation noise. Numerical simulations are presented for the UUV in water, and reliable results have been obtained.

A Simple Method for Combined Fluorescence In Situ Hybridization and Immunocytochemistry

  • Moon, Il Soo;Cho, Sun-Jung;Jin, IngNyol;Walikonis, Randall
    • Molecules and Cells
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    • v.24 no.1
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    • pp.76-82
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    • 2007
  • By combining in situ hybridization (ISH) and immunocytochemistry (IC), microscopic topological localization of mRNAs and proteins can be determined. Although this technique can be applied to a variety of tissues, it is particularly important for use on neuronal cells which are morphologically complex and in which specific mRNAs and proteins are located in distinct subcellular domains such as dendrites and dendritic spines. One common technical problem for combined ISH and IC is that the signal for immunocytochemical localization of proteins often becomes much weaker after conducting ISH. In this manuscript, we report a simplified but robust protocol that allows immunocytochemical localization of proteins after ISH. In this protocol, we fix cultured cortical or hippocampal neurons with 4% paraformaldehyde (PFA), rinse briefly in PBS, and then further fix the cells with $-20^{\circ}C$ methanol. Our method has several major advantages over previously described ones in that (1) it is simple, as it is just consecutive routine fixation procedures, (2) it does not require any special alteration to the fixation procedures such as changes in salt concentration, and (3) it can be used with antibodies that are compatible with either methanol (MeOH-) or PFA-fixed target proteins. To our best knowledge, we are the first to employ this fixation method for fluorescence ISH + IC.

An Exploration of the maternal & paternal-fetal attachment (임신한 부부의 태아 애착에 관한 연구)

  • Ahn, Suk-Heui
    • 모자간호학회지
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    • v.3 no.1
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    • pp.49-63
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    • 1993
  • The purpose of the study was to identify the maternal & paternal-fetal attachment. The subjects were 130 pregnant women and 85 their husbands. Data were collected in OB & GY clinic by modified Cranley's Maternal-Fetal Attachment Scale. The results were as follows : 1. The mean scores of maternal-fetal attachment (MFA) was 75.57(range: 48-92). The most frequently practiced attachment item was "I can hardly walt to hold the baby(mean 4.32)". The mean scores of paternal-fetal attachment (PFA) was 65.48(range : 48-92). The most frequently practiced attachment item was "I can hardly wait to hold the baby(mean 4.25)". 2. There were significant difference in the degree of MFA, namely, gestational period(p=.020), whether the women had been special things(p=.000) and had experiened on ultrasound scan(p=.001). In the PFA, gestational period(p=.013) gravida(p=.016), duration of marriage(p=.001), family type(p=.036) and whether the women had a health problem(p=.035) were significant difference in degree of attachment. In conclusions, it can be said that parent demonstrated mid-level of attachment to their fetus during pregnancy. Several other factors seemed to be related, indicating a need for further study on maternal & paternal-fetal attachment. It will designed and managed parental class to promoting maternal & paternal-fetal attachment.

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The Influence of Glutaraldehyde Concentration on Electron Microscopic Multiple Immunostaining

  • Bae, Jae Seok;Yeo, Eun Jin;Bae, Yong Chul
    • International Journal of Oral Biology
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    • v.40 no.4
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    • pp.183-187
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    • 2015
  • The present study was aimed to evaluate the influence of glutaraldehyde (GA) concentration on multiple electron microscopic (EM) immunostaining using pre-embedding peroxidase and post-embedding immunogold method. Influence of various concentrations of GA included in the fixative on immuoreactivity was assessed in the multiple immunostaining using antisera against anti-transient receptor potential vanilloid 1 (TRPV1) for peroxidase staining and anti-GABA for immunogold labeling in the rat trigeminal caudal nucleus. Anti-TRPV1 antiserum had specificity in pre-embedding peroxidase staining when tissues were fixed with fixative containing paraformaldehyde (PFA) alone. Immunoreactivity for TRPV1 was specific in tissues fixed with fixative containing 0.5% GA at both perfusion and postfixation steps, though the immunoreactivity was weaker than in tissues fixed with fixative containing PFA alone. Tissues fixed with fixative containing 0.5% GA at the perfusion and postfixation steps showed specific immunogold staining for GABA. The results of the present study indicate that GA concentration is critical for immunoreactivity to antigens such as TRPV1 and GABA. This study also suggests that the appropriate GA concentration is 0.5% for multiple immunostaining with peroxidase labeling for TRPV1 and immunogold labeling for GABA.

Suppressio of mutual interference among vehicular radars by ON-OFF control of pulses (다중차량의 자동 주행 시의 레이터 상호간섭 억제)

  • 최병철;김용철
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.1B
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    • pp.62-70
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    • 2000
  • Intelligent vehicles are equipped with radar sensors for collision avoidance. We present a method of suppressing mutual interference among pulse-type radars, where all the radars are standardized. We developed a method of separating the true self-reflection from the false one by controlling the pulse emission of a radar in anorhogonal ON, OFF pattern. Interference signal identified in OFF-intervals is recorded to indicate the positions of the expected ghosts in ON-intervals. PFA and PM are derived for a radar system with I-Q demodulation scheme, where Gaussian noise alone is Rayleigh-distributed and Gaussian noise plus reflected radar pulse are Rician-distributed. The value of the threshold adaptively updated in order to prevent the deterioration of PM. In the experimental result, PFA decreases by an order of 10,000, when compared with the conventional M of N majority voting method.

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Experimental Study on Power Flow Analysis of Vibration of an Automobile Door (자동차 도어 진동의 파워흐름해석에 대한 실험적 연구)

  • Kil, H.G.;Lee, Y.H.;Lee, G.H.;Hwang, S.G.;Hong, S.Y.;Park, Y.H.;Seo, J.K.;Chae, G.S.;Seo, S.H.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.05a
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    • pp.782-785
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    • 2006
  • The Power Flow Analysis(PFA) can be effectively used to predict structural vibration in medium-to-high frequency range. In this paper, Power Flow Finite Element Method (PFFEM) based on PFA has been used to predict the vibration of an automobile door. The predicted results for the frequency response function of the door have been compared with corresponding experimental results. In the experiment, the automobile door has been divided into several subsystems and the loss factor of each subsystem has been measured. The input mobility at a source point has been also measured. The data for the loss factors and the input mobility have been used as the input data to predict the vibration of the automobile door with PFFEM. The frequency response functions have been measured over the surface of the door. The comparison between the experimental results and the predicted results for the frequency response functions showed that PFFEM could be an effective tool to predict the structural vibration.

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Vibration and Noise Analysis for Rotary Compressor in Medium-to-high Frequency Ranges (중고주파수 대역의 회전형 압축기 진동소음 해석)

  • Kwon, Hyun-Wung;Song, Jee-Hun;Hong, Suk-Yoon;Hwa, Jong-Hun
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.22 no.11
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    • pp.1033-1041
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    • 2012
  • Power flow analysis(PFA) is introduced for solving the noise and vibration analysis of system structures in medium-to-high frequency ranges. The vibration analysis software, $PFADS_{C++}$ R4 based on power flow finite element method(PFFEM) and the noise prediction software, $NASPFA_{C++}$ R1 based on power flow boundary element method(PFBEM) are developed. In this paper, the coupled PFFE/PFBE method is used to investigate the vibration and radiated noise of the rotary compressor. PFFEM is employed to analyze the vibrational responses of the rotary compressor, and PFBEM is applied to analyze the radiation noise around rotary compressor. The vibrational energy of the structure is used as an acoustic intensity boundary condition of PFBEM. Numerical simulations are presented for the rotary compressor, and reliable results have been obtained.

Anti-Obesity Effect of Fructus Pyri Pyrifoliae Extract Fermented by Lactic-Acid Bacteria on Rats

  • Chu, Hanna;Kim, Jeongsang
    • Applied Microscopy
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    • v.48 no.3
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    • pp.62-72
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    • 2018
  • This study investigated the anti-obesity effect of a pear (Fructus Pyri Pyrifoliae) extract fermented by lactic-acid bacteria on obesity induced by a high-fat diet in rats. Body-weight measurement, blood analysis, and light microscope observation of adipose tissue in liver and epididymis were conducted after 8 weeks. Gene expression of leptin, adiponectin, and tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) in liver cells were also investigated. Compared to CON, PFA and PFB showed 8% weight reduction along with weight reduction of adipose tissue in liver and epididymis. Observing the microstructure of liver cells showed that lipid droplets were smaller in PFA and PFB than in CON. We confirmed that Fructus Pyri Pyrifoliae extract fermented by lactic-acid bacteria can affect gene expression of leptin, adiponectin, and $TNF-{\alpha}$ in liver cells, showing an obesity treatment effect. From the results above, it was observed that weight gain from increased gene expression in adipose cells as well as from the increased proportion of adipose cells caused by a high-fat diet can be statistically significantly reduced by taking Fructus Pyri Pyrifoliae extract fermented by lactic-acid bacteria. Therefore, Fructus Pyri Pyrifoliae extract fermented by lactic-acid bacteria can be effective for preventing and treating obesity by reducing weight and adipose cells.

A Novel Prediction-based Spectrum Allocation Mechanism for Mobile Cognitive Radio Networks

  • Wang, Yao;Zhang, Zhongzhao;Yu, Qiyue;Chen, Jiamei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.9
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    • pp.2101-2119
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    • 2013
  • The spectrum allocation is an attractive issue for mobile cognitive radio (CR) network. However, the time-varying characteristic of the spectrum allocation is not fully investigated. Thus, this paper originally deduces the probabilities of spectrum availability and interference constrain in theory under the mobile environment. Then, we propose a prediction mechanism of the time-varying available spectrum lists and the dynamic interference topologies. By considering the node mobility and primary users' (PUs') activity, the mechanism is capable of overcoming the static shortcomings of traditional model. Based on the mechanism, two prediction-based spectrum allocation algorithms, prediction greedy algorithm (PGA) and prediction fairness algorithm (PFA), are presented to enhance the spectrum utilization and improve the fairness. Moreover, new utility functions are redefined to measure the effectiveness of different schemes in the mobile CR network. Simulation results show that PGA gets more average effective spectrums than the traditional schemes, when the mean idle time of PUs is high. And PFA could achieve good system fairness performance, especially when the speeds of cognitive nodes are high.

Estimation and Application of Turbulent Flow-Induced Input Power for Vibrational Power Flow Analysis (진동파워흐름해석을 위한 난류흐름에 의한 입력파워 추정 및 적용)

  • Lim, Gu-Sub;Hong, Suk-Yoon;Park, Young-Ho;Choi, Young-Dal;Joung, Tea-Seok
    • Special Issue of the Society of Naval Architects of Korea
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    • 2008.09a
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    • pp.96-105
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    • 2008
  • Turbulent flow-induced vibrations generate the structural fatigue and noise problems. In this paper, using Corcos, Smol' yakov-Tkachenko, Ffowcs Williams and Chase models, the input power generated by distributed fluid force is predicted for power flow analysis (PFA) of turbulent flow-induced vibration. Additionally, the Fast Fourier Transform (FFT) is used to raise the calculation efficiency PFA results obtained are compared with the classical modal solutions for verifications. Analytic results using the fluid models show good agreements with those of modal analysis, respectively.

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