• Title/Summary/Keyword: Frequency dependence

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A Study on the Relationship between Perception of Self and Clothing Interest for A Group of Elderly Women in Seoul (노년기 여성의 자아지각과 의복관심과의 상관연구)

  • Jeong Hee Yong;Rim Sook Ja
    • Journal of the Korean Society of Clothing and Textiles
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    • v.12 no.3 s.28
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    • pp.333-342
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    • 1988
  • The purpose of this study was to investigate the relationship between Perception of self anp Clothing Interest, and to determine the difference of Clothing interest and Perception of self by the demographic variables. Perception of self was measured with Perception of self test from Choi's Perceptual Orientation Scale. Appearance, Clothing comfort, Fashion, Psychological dependence, Clothing economics were measured with items from Gurel's Study and Creekmore's for method of measuring clothing variables, items were drawn from preceding measures and, slightly modified. Data were affected from 305 purposively selectee! elderly women over sixty dwelling in Seoul by means of interview and questionnaire. For statistical analyses, frequency distribution, ANOVA, Duncan's multiple Range test, Pearson's Correlation coefficients were used. The results were as follows; 1. The three groups classified, by Perception of self were Positively Correlated to Appearance, Fashion and Psychological dependence. 2. There was partially significant difference between clothing interest and demographic variables. Education and socioeconomic status affected Psychological dependence. Demographic variables not affected Clothing comfort. 3. There was partially significant difference between Perception of self and demographic variables. Age, education, marital status and socioeconomic status affected Perception of Self. 4. There was partially significant relationships among subscales of the Clothing interest. Appearance was positively correlated to clothing comfort, Fashion and Psychological dependence, clothing comfort was positively correlated to Appearance, Psychological dependence. Fashion was positively correlated to Appearance, Clothing comfort and, Psychological dependence.

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The Dependence of Frequency Change Perception on the Acoustics of a Listening Environment and Its Implication for the Evaluation of Room Acoustics

  • Jeong, Dae-Up
    • The Journal of the Acoustical Society of Korea
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    • v.18 no.4E
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    • pp.10-19
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    • 1999
  • Psychophysical approaches to the room acoustics have been made in number of researches. The present study is looking at whether the listener's perception of frequency change in rooms are dependent on the acoustics of a listening environment. P(C)s for frequency change in short tones were measured in different listening conditions. Two experiments were carried out to investigate the influence of room acoustics on the listener's perception of frequency change, and its implication for evaluating the acoustics of listening environments were examined and discussed. It was found that the temporal and spectral contents of reflections from room surfaces might be an important factor which influenced the listener's perception of frequency change in a reverberant sound field. This implicates that psychophysical approach by measuring listener's frequency change perception might be an useful tool for evaluating room acoustics. However, cares should be taken, since some individual differences were found to exist with respect to the direction of frequency change.

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A exploratory study for Influential factors of smartphone over-dependence in elder and older Group (장·노년층의 스마트폰 과의존 영향요인에 대한 탐색적 연구)

  • Bae, Sung-Man;Koh, Young-Sam
    • Journal of Digital Convergence
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    • v.15 no.7
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    • pp.111-121
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    • 2017
  • Smartphone use has become a part of everyday life, not only for adolescents but also for elderly and older people. Thus, this study explored the effect of demographic variables, the amount of smartphone usage, type of smartphone use and psychosocial variables on smartphone dependence of the elder group. We analyzed the data of 5627 (50s and 60s) of the Internet overdependence survey data of the Korea Information Society Agency in 2016. As a result of hierarchical multiple regression analysis, More frequency of smartphone use of weekday and weekend, and usage time of smartphone of weekday were related to greater smartphone dependence. More smartphone use for information seeking and games were associated with greater smartphone dependence. And, as loneliness and anxiety increased, smartphone dependence increased, while smartphone dependence decreased, as social capital increased. Through this study, it is necessary to understand characteristics related to smartphone dependence of elder and older group, and to use this knowledge to solve their smartphone dependence. Future studies also need to identify the causal relationship between predictors of smartphone dependence in elderly and older people.

Analysis of the Influence of Mutual Relation of Optical Pulse Frequency Chirp and Kerr Effect on the Mid-Span Spectral Inversion Methods for the Long-Haul Optical Transmission (광 펄스 주파수 첩과 Kerr 효과의 상호 관계가 장거리 광 전송을 위한 MSSI 보상 기법에 미치는 영향 분석)

  • 이성렬;이윤현
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.13 no.9
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    • pp.898-906
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    • 2002
  • In this paper, we investigated the improvement degree of transmission distance of the various initial frequency chirped optical pulse with 5 dBm initial power dependence on the various bit rate and fiber dispersion coefficient, when MSSI(Mid-Span Spectral Inversion) with the optimal pump power condition is adopted for the compensation method for optical pulse distortion. And we analyzed the influence of mutual relation of optical pulse frequency chirp and Kerr effect on the MSSI methods for the long-haul optical transmission through the computer simulation. We found that the compensation degree of distorted optical pulse varies as a consequence of the variation of combined phase modulation of self phase modulation(Kerr effect) and initial frequency chirp parameter dependence on the fiber dispersion coefficient. And we found that, if the transmission bit rate is increased k times, the dispersion coefficient value of dispersion shift fiber is decreased $2^k$ times so as to be almost the same performance of the transmission system with k times lower bit rate.

A Study on Spectral Characteristics of Ultrasonic Signal for Tissue Attennation Coefficient Measurement (생체내의 초음파 감쇄계수를 측정하기 위한 초음파 신호스펙트럼 특성에 관한 연구)

  • Huh, Woong
    • Journal of Biomedical Engineering Research
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    • v.4 no.1
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    • pp.29-36
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    • 1983
  • In this paper, center frequency down slift of ultrasonic echo signals which for the measurements of frequency dependent attenuation in the biological tissue are estimated. Center frequency down shift of echo-signals are estimated after signal spectrum analysis of whole echo-signals. In case of signal spectrums are simple, estimation of down shift frequency is very simple and in case of complicate spectrum, estimation of down shift frequency is depend on spectral shape. In case of unable to estimate, frequency dependence of medium is nonlinear(n) 1), in which upper shift of spectrums are presented. In case of unable to estimate, spectrum analysis are performed at local position. At consquence, we know that spectral dispersions are caused complicately by biological tissue layer.

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Frequency Dependent Grounding Impedance As a Function of Soil Resistivity (대지저항률에 따른 접지임피던스의 주파수 의존성)

  • Bae, Sung-Bae;Choi, Jong-Hyuk;Park, Geon-Hun;Lee, Bok-Hee
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2008.05a
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    • pp.57-60
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    • 2008
  • A design criterion of grounding systems is commonly based on low frequency resistance in Korea. When lightning surges which have high frequency components are injected into the grounding system, the grounding impedance is greatly different from the static grounding resistance. This paper presents the grounding adimittance and phase on the frequency range from 100 [Hz] to 15 [MHz] using water tank simulating the grounding system in different water resistivities. As a result, capacitive effect is dominant over the frequency of 100 [kHz] at the water resistivity of 1,000 [$\Omega$ m]. On the other hand, the inductive characteristics appear at the low water resistivity. Consequently, dependence of grounding impedances on the frequency of injected current is strongly related to resistivity.

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Frequency Dependence in Large Strain Range During Cyclic Triaxial Tests of Clay (점성토의 진동삼축시험시 대변형률영역에서의 주파수 의존성)

  • Kim, Yong-Seong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.48 no.5
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    • pp.63-71
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    • 2006
  • In the present study, the dynamic deformation characteristics of clay, including the effect of loading rate in large strain ranges, were examined by performing undrained cyclic triaxial test. The test results showed that the loading rate to failure decreased with increasing loading amplitude and decreasing loading frequency. While the stress-strain relationships was not affected by loading frequency, excess pore pressure was affected significantly with the change in loading frequency. The change for 0.1 Hz was larger for than that of 0.01 Hz, resulting in inclined effective stress paths. Furthermore, the lower the frequency was, the higher the excess pore pressure was in the first loading.

Development & Verification of Frequency-Strain Dependence Curve (주파수-변형률 곡선의 개발 및 검증)

  • Jeong, Chang-Gyun;Kwak, Dong-Yeop;Park, Du-Hee
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.03a
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    • pp.146-153
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    • 2009
  • One dimensional site response analysis is widely used in prediction of the ground motion that is induced by earthquake. Equivalent linear analysis is the most widely used method due to its simplicity and ease of use. However, the equivalent linear method has been known to be unreliable since it approximates the nonlinear soil behavior within the linear framework. To consider the nonlinearity of the ground at frequency domain, frequency dependent algorithms that can simulate shear strain - frequency dependency have been proposed. In this study, the results of the modified equivalent linear analysis are compared to evaluate the degree of improvement and the applicability of the modified algorithms. Results show the novel smoothed curve that is proposed by this study indicates the most stable prediction and can enhance the accuracy of the prediction.

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Verification of Frequency-Dependent Equivalent Linear Method (주파수 의존성을 고려한 등가선형해석기법의 검증)

  • Jeong, Chang-Gyun;Kwak, Dong-Yeop;Park, Du-Hee
    • Journal of the Korean Geotechnical Society
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    • v.24 no.12
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    • pp.113-120
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    • 2008
  • One-dimensional site response analysis is widely used to simulate the seismic site effects. The equivalent linear analysis, which is the most widely used type of site response analysis, is essentially a linear method. The method applies constant shear modulus and damping throughout the frequency range of the input motion, ignoring the dependence of the soil response on the loading frequency. A new type of equivalent linear analysis method that can simulate the frequency dependence of the soil behavior via frequency-strain curve was developed. Various forms of frequency-strain curves were proposed, and all curves were asserted to increase the accuracy of the solution. However, its validity has not been extensively proven and the effect of the shape of the frequency-strain curve is not known. This paper used two previously proposed frequency-strain curves and three additional curves developed in this study to evaluate the accuracy of the frequency-dependent equivalent linear method and the influence of the shape of the frequency-strain curves. In the evaluation, six recordings from three case histories were used. The results of the case study indicated that the shape of the frequency-strain curve has a dominant influence on the calculated response, and that the frequency dependent analysis can enhance the accuracy of the solution. However, a curve that results in the best match for all case histories did not exist and the optimum curve varied for each case. Since the optimum frequency-strain curve can not be defined, it is recommended that a suite of curves be used in the analysis.

Examination of Frequency Dependence of Iron Loss in Magnetic Field Analysis

  • Masato Enokizono;Yuji Fujita
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • v.11B no.3
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    • pp.59-63
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    • 2001
  • This paper presents a new modeling of the two dimensional magnetic property in soft magnetic materials for the magnetic field computations. In this modeling an approximate treatment is introduced to expand the applicable exciting frequency range. The result shows that the new modeling presented here is very useful in simplicity of magnetic field analysis.