• Title/Summary/Keyword: Progressive frequency

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A Progressive DCT Image Coding by Non-sequential Bit Ordering (비순차적 비트 정렬에 의한 점진적인 DCT 영상 부호화)

  • 김종훈;채종길;심영석
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.3
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    • pp.69-79
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    • 1994
  • DCT image coding has been well known for its compression efficiency. Its nature makes it also suitable for efficient progressive transmission and reconstruction since low frequency transform coefficients contain most of the energy of image signals. In this paper, we propose a progressive transmission technique of DCT image by non-sequential bit ordering using Lloyd-Max quantizer. And then, we will show that the Lloyd-Max quantizer can be embedded quantization. In simulation results, the proposed method show better subjective picture and MSE of the reconstructed image than the conventional zig-zag scanning transmission of transform coefficients.

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Effect of Progressive Muscle Relaxation using Biofeedback on Perceived Stress, Stress Response, Immune Response and Climacteric Symptoms of Middle-Aged Women (바이오피드백을 이용한 점진적 근육이완이 중년여성의 지각된 스트레스, 스트레스반응, 면역반응 및 갱년기 증상에 미치는 효과)

  • 정인숙
    • Journal of Korean Academy of Nursing
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    • v.34 no.2
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    • pp.213-224
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    • 2004
  • Purpose: This study was aimed to evaluate the effect of progressive muscle relaxation training using biofeedback on perceived stress, stress response, immune response and climacteric symptoms, Method: This was a crossover, pre-post test design, The study subjects are 36 middle-aged women who were selected at 2 public health centers, The independent variable was Biofeedback training for 4 weeks, twice a week and home training for 4 weeks, Dependent variables were perceived stress, stress response, immune response, and climacteric symptoms measured with Hildtch's scale (1996), Result: Progressive muscle relaxation training using biofeedback was not effective in reducing perceived stress, but it was shown to be effective in reducing physiological stress responses such as pulse rate and EMG, Though blood pressure and skin conductance were repeatedly down, and skin temperature slowly increased, there were no statistically significant differences. Progressive muscle relaxation training using biofeedback was not effective in reducing serum cortisol, enhancing immune responses, or decreasing climacteric symptoms. Conclusion: The findings point to a pressing need for further, well-controlled and designed research with consideration in selection of subjects and instruments, frequency of measurements, the sampling method, and intervention modalities.

Development of High Precision R/F Switch Connector Shell for Mobile Phone by Embossing and Burring Process (엠보싱 및 버링 공법을 이용한 휴대폰용 초정밀 알 에프 스위치 커넥터 쉘 개발)

  • Choi, H.S.;Shin, H.J.;Kim, B.M.;Ko, D.C.
    • Transactions of Materials Processing
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    • v.22 no.6
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    • pp.317-322
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    • 2013
  • A radio frequency(R/F) switch connector is widely used in wireless devices such as mobile phone and navigator to check defects of the circuit board of product. The R/F switch connector shell plays a role in protecting the switch connector. Previously, this part was machined using a turning, which is time-consuming and has poor material utilization. Furthermore, the workpiece material of brass containing lead that has excellent machinability has environmentally regulated during recent years. The purpose of the current study was to develop the connector shell by forming through progressive dies including embossing, burring and forging process in order to achieve higher productivity and dimensional accuracy without tool failure. To accomplish this objective, a strip layout was designed and finite element (FE) analysis was performed for each step in the process. Try-out for the connector shell was conducted using progressive die design based on FE-analysis results. Dimensional accuracy of developed part was investigated by scanning electron microscopy. The result of the investigation for the dimensions of the formed connector shell showed that the required dimensional accuracy was satisfied. Moreover, productivity using the progressive die increased four times compared to previous machining process.

Spectral Analysis of Heart Rate Variability during Treadmill Exercise at Various Speeds and Grades

  • Kim, Hyeong-Jin;Kim, Ki-Hong;Ahn, Dong-Kuk;Park, Jae-Sik
    • The Korean Journal of Physiology
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    • v.30 no.1
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    • pp.43-51
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    • 1996
  • This study was aimed to elucidate the changes in heart rate variability during treadmill exercise at various speeds and grades by spectral analysis. Thirty-three untrained male college students aged $20{\sim}26\;yr $were employed to exercise on a treadmill using 4 speeds (4.02, 5.47, 6.76 and 8.05 km/h) and 6 grades (0, 4, 8, 12, 16 and 20%). A fixed speed was selected for each session with the grade increased every 3 min. The electrocardiogram, respiration and the stepping activity were continuously recorded through an A/D converter system on the computer disk. Power spectra of heart rate variability (RRV) were obtained by use of a fast Fourier transform algorithm. The frequency domain was divided into 3 bands: $VLF\;(0{\sim}0.04\;Hz),\;LF\;(0.04 {\sim}0.15\;Hz)\;and\;HF\;(0.15{\sim}1.00\;Hz).$ Heart rate was $74.4{\pm}2.1\;beats/min$ at rest and showed a steady increase during treadmill exercise with increasing speed and grade up to $196.7{\pm}5.0\;beats/min.$ Total power of HRV was $35.0{\pm}6.7\;(beats/min)^{2}$ at rest and progressively decreased during exercise down to $1.9{\pm}0.3\;(beats/min)^{2}.$ The %VLF power of HRV was $34.5{\pm}3.7\; %$ at rest and showed no significant change during exercise except for a decrease observed at the highest intensity of exercise. The %LF power was $44.1{\pm}3.0\;%$ at rest and showed a progressive decrease down to $4.5{\pm}1.0\;%$ during those stages of exercise where heart rate was over 135 beats/min. The %HF power was $21.4{\pm}2.9\;%$ at rest and showed a progressive increase up to $87.1{\pm}6.7\;%$ during higher intensity exercise where heart rate was over 165 beats/min. Peak frequency of HF band was $0.200{\pm}0.018\;Hz$ at rest and was shifted to higher frequencies up to $0.909{\pm}0.048\;Hz$ at heart rates greater than 135 beats/min. Respiratory frequency was $18.0{\pm}1.5$ breaths/min at rest and significantly increased during exercise up to $53.0{\pm}3.7$ breaths/min. Stride frequency during treadmill exercise showed an increasing tendency with increasing speed from $55.6{\pm}0.9$ steps/min at 4.02 km/h to $81.2{\pm}0.6$ at 8.05 km/h. It was concluded that total power of HRV decreased progressively with increasing exercise intensity due to the withdrawal of parasympathetic activity. At higher exercise intensity, % LF power decreased and %HF power increased with its peak frequency shifted to higher values in a progressive mode with increasing speed and grade, reflecting a readjustment in the cardiovascular system and the increased respiration and its rate, respectively.

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A Case of Mitochondrial Respiratory Chain Defect with Progressive Bilateral Cararacts (진행성 양측 백내장이 동반된 미토콘드리아 질환 1례)

  • Lee, Soonie;Lee, Young-Mock
    • Journal of The Korean Society of Inherited Metabolic disease
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    • v.18 no.3
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    • pp.95-98
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    • 2018
  • A striking feature of mitochondrial disorders is the vast heterogeneity in their clinical symptoms that ranges from a single organ to severe multisystem involvement. Though a variety of ocular symptoms such as ptosis, pigmentary retinal degeneration, external ophthalmoplegia, and optic nerve atrophy can occur in association with mitochondrial cytopathies, progressive bilateral cataracts are rare among their ocular findings. A 5-year-old girl with no previous medical history came to our hospital presenting symptoms of seizure. She started showing progressive developmental regression, increased seizure frequency, hypotonia, general weakness, dysphagia and decreased vision. Lactic acidosis was noted in metabolic screening test and we confirmed mitochondrial respiratory chain complex I defect in spectrophotometric enzyme assay using the muscle tissue. Progressive bilateral cataracts then developed and were fully evident at the age of 7. She underwent cataract extraction with posterior chamber lens implantation. We are reporting a case of mitochondrial respiratory chain defect with multiorgan involvements including bilateral progressive cataract, an uncommon ocular manifestation. Ophthalmologic evaluation is highly recommended not to overlook the possible ocular manifestations in mitochondrial disorders.

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Control of a batch reactor by learning operation

  • Lee, Kwang-Soon;Cho, Moon-Khi;Cho, Jin-Won
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10b
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    • pp.1277-1283
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    • 1990
  • The iterative learning control synthesized in the frequency domain has been utilized for temperature control of a batch reactor. For this purpose, a feedback-assisted generalized learning control scheme was constructed first, and the convergence and robustness analyses were conducted in the frequency domain. The feedback-assisted learning operation was then implemented in a bench scale batch reactor where reaction heat is simulated using an electric heater. As a result, progressive reduction of temperature control error could be obviously observed as batch operation is repeated.

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(A Progressive Image Coding by Wavelet Coefficient Property) (웨이브렛 계수 특성을 이용한 점진적 영상 부호화)

  • 장윤업
    • Journal of the Korea Computer Industry Society
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    • v.3 no.9
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    • pp.1287-1294
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    • 2002
  • The algorithm method for progressive image coding based on discrete wavelet transform presented in a paper. After discrete wavelet transform and extract edge information through edge detection, and then designed efficient coding method more then established embedded coding algorithm using expanded EZW algorithm. Generally, edges have a relatively higher influence on image reconstruction. Occurred DWT on image, and can classify significant coefficients and non-significant coefficients. Using property that edge part has appeared significant coefficient in the paper. Especially, we confirmed that higher frequency sub region on DWT image present homogenous direction property. And on embedded coding, which are effective and well-directed information have higher priority to image reconstruction on transmission. Therefore, our technique algorithm system perform better than that of the conventional method such as progressive image coding application.

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A Study on the Japanese Female College Students' lifestyle and Clothing Benefits Sought (일본 여대생의 라이프스타일과 의복 추구 혜택과의 관계 연구)

  • Lee Ok-Hee
    • The Research Journal of the Costume Culture
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    • v.13 no.6 s.59
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    • pp.857-870
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    • 2005
  • The purpose of this study was to identify the relationship between lifestyles and clothing benefits pursuit. A questionnaire was developed to measure lifestyle and clothing benefits sought. The questionnaire was distributed and collected from 131 college female students in Tokyo. The data was analyzed by percentage, frequency, mean, standard deviation, factor analysis, reliability test, MANOVA and ANOVA by SPSS package. The lifestyles of the respondents were classified into five types such as recreational-oriented, fashion-oriented, progressive-oriented, intentional purchasing, and economics-oriented type. And clothing benefits pursuit was classified into five types such as individuality-pursuit, brand-pursuit, convenience-pursuit, fashion -pursuit, and coordination/figure flaws compensation-pursuit. The result of this study were as follows; 1) All of three lifestyle groups of appearance-oriented type, fashion-oriented type, intentional purchasing type had an inclination for individuality-pursuit, brand-pursuit, fashion-pursuit, and not an inclination for convenience-pursuit. 2) The higher the fashion-oriented and intentional purchasing, and the lower the progressive-oriented and economics-oriented were, the higher was individuality-pursuit. 3) The higher progressive-oriented and the lower recreational-oriented were, the higher convenience-pursuit was. 4) The brand-pursuit, convenience-pursuit, and fashion-pursuit were not shown to have the significant differences according to intentional purchasing group.

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Effect of bidirectional internal flow on fluid.structure interaction dynamics of conveying marine riser model subject to shear current

  • Chen, Zheng-Shou;Kim, Wu-Joan
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.4 no.1
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    • pp.57-70
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    • 2012
  • This article presents a numerical investigation concerning the effect of two kinds of axially progressing internal flows (namely, upward and downward) on fluid.structure interaction (FSI) dynamics about a marine riser model which is subject to external shear current. The CAE technology behind the current research is a proposed FSI solution, which combines structural analysis software with CFD technology together. Efficiency validation for the CFD software was carried out first. It has been proved that the result from numerical simulations agrees well with the observation from relating model test cases in which the fluidity of internal flow is ignorable. After verifying the numerical code accuracy, simulations are conducted to study the vibration response that attributes to the internal progressive flow. It is found that the existence of internal flow does play an important role in determining the vibration mode (/dominant frequency) and the magnitude of instantaneous vibration amplitude. Since asymmetric curvature along the riser span emerges in the case of external shear current, the centrifugal and Coriolis accelerations owing to up- and downward internal progressive flows play different roles in determining the fluid.structure interaction response. The discrepancy between them becomes distinct, when the velocity ratio of internal flow against external shear current is relatively high.

Effect of generalized thermoelasticity materials with memory

  • Baksi, Arup;Roy, Bidyut Kumar;Bera, Rasajit Kumar
    • Structural Engineering and Mechanics
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    • v.25 no.5
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    • pp.597-611
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    • 2007
  • Many works have been done in classical theory of thermoelasticity in materials with memory by researchers like Nunziato, Chen and Gurtine and many others. No work is located in generalized thermoelasticity regarding materials with memory till date. The present paper deals with the wave propagation in materials with memory in generalized thermoelasticity. Plane progressive waves and Rayleigh waves have been discussed in details. In the classical theory of heat conduction it was observed that heat propagates with infinite speed. This paradox has been removed in the present discussion. The set of governing equations has been developed in the present analysis. The results of wave velocity and attenuation coefficient corresponding to low and high frequency have been obtained. For thermal wave the results show appreciable differences with those in the usual thermoelasticity theory.