• Title/Summary/Keyword: Coherence 분석

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Analyzing Coherence of Evidences and Claims Presented in Elementary Students' Science Writing for Inquiry Activities (초등학생의 탐구 활동 과학 글쓰기에서 나타난 증거와 주장의 정합성 분석)

  • Lee, Sung-Hee;Shin, Myeong-Kyeong;Lee, Gyu-Ho;Lee, Sun-Kyung;Kwon, Nan-Joo
    • Journal of Korean Elementary Science Education
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    • v.29 no.4
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    • pp.505-514
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    • 2010
  • This study aims to explore group inquiry using science writing heuristic in elementary school science. We observed and examined what elementary students experienced in their science classes and moreover how they used their data to support their claims in the view point of scientific epistemology. The research question of this study is 'what is the result of coherence measurement for figuring out the relationship between argument and ground in group inquiry activity?'. To solve the study question, one fifth-grade class at an elementary school was selected. Four lessons in group inquiry using a worksheet of science writing heuristic were videotaped and transcribed. It was found that the hours of group inquiry when students can discuss meaningfully occupied approximately 37 to 45%. When measuring coherence in each lesson by developing a scale from one to five to estimate the coherence of the work sheet designed, the total average was 3.424. It implicated that students had their claims supported by some of their evidences. Although the figure was not enough to assist that they found strong bonds between their claims and data, they started to move forward to epistemological approach in their science lab works.

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The Organization and Coherence of the Geography Experimental Textbooks in Chinese Senior Secondary Schools (중국의 고급중학교 지리교과서 내용체계와 정합성)

  • Kang, Chang-Sook
    • Journal of the Korean association of regional geographers
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    • v.19 no.1
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    • pp.181-200
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    • 2013
  • The Chinese Geography Standards for Senior Secondary Schools(trial) was released in 2003. The Standards put forward some changes for senior geography education, the changes in geographical education are reflected explicitly and implicitly by the textbooks. The purpose of this descriptive study was to review of the improvement of Chinese senior geography education by analyzing contents organization and coherence of the new standards-based geography experimental textbooks. The results of study are as follows. The textbooks adopts a student-centered approach through the way of 'more chapter topics with slimmed contents' and by introducing four type activities, geographical inquiries. These student activities are implicity encourages students' active acquisition of geographical knowledge what they have learned in their real lives. The organic coherence of the textbooks' contents rests on the compulsory and the elective subject relating to diversification of the learning areas. The organic coherence between the compulsory and the elective subject rests on diversification of the learning areas. More, looking at the arrangement of the four basic concepts(population, resource, environment, sustainable development) among the textbooks, it was imbalanced by subject.

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Connectivity Analysis Between EEG and EMG Signals by the Status of Movement Intention (운동 의도에 따른 뇌파-근전도 신호 간 연결성 분석)

  • Kim, Byeong-Nam;Kim, Yun-Hee;Kim, Laehyun;Kwon, Gyu-Hyun;Jang, Won-Seuk;Yoo, Sun-Kook
    • Science of Emotion and Sensibility
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    • v.19 no.1
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    • pp.31-38
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    • 2016
  • The brain and muscles both of which are composed of top-down structure occur the connectivity with the change of Electroencephalogram(EEG) and Electromyogram(EMG). In this paper, we studied the difference of functional connectivity between brain and muscles that by applying coherence method to EEG and EMG signals when users exercised upper limb with and without the movement intention. The changes in the EEG and EMG signals were inspected using coherence method. During the upper limb exercise, the mu (8~14 Hz) and beta (15~30 Hz) rhythms of the EEG signal at the motor cortex area are activated. And then the beta and piper (30~60 Hz) rhythms of the EMG signal are activated as well. The result of coherence analysis between EEG and EMG showed the coefficient of active exercise including movement intention is significantly higher than passive exercise. The coherence relations between cognitive response and muscle movement could interpret that the connectivity between the brain and muscle appear during active exercise with movement intention. The feature of coherence between brain and muscles by the status of movement intention will be useful in designing the rehabilitation system requiring feedback depending on the users' movement intention status.

The Effect of Stress and Sense of Coherence on Health Behavior Compliance in Outpatients with Stroke (뇌졸중 환자의 스트레스와 통합성이 건강행위 이행에 미치는 영향)

  • Lee, Won Joo;Lee, Ji Won
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.1
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    • pp.232-239
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    • 2020
  • The purpose of this study was to identify the effect of stress and sense of coherence on health behavior compliance in patients with stroke. The subjects were 124 outpatients with stroke at a general hospital in Ulsan from May to July, 2019. The data were analyzed using descriptive statistics, t-test, one-way ANOVA, Scheffé test, Pearson's correlation coefficient and hierarchical multiple regression analysis by using SPSS 25.0. In the results, the health behavior compliance showed a significantly positive correlation with sense of coherence(r=.71, p<.001) and a negative correlation with stress(r=-.53, p<.001). The predictors of model 1 were gender(t=4.07, p<.001), education level(t=4.18, p<.001), and monthly income(t=-2.34, p=.021) and the statistical power was 39.6%. The predictors of model 2 were gender(t=4.65, p<.001), education level(t=43.24, p<.001), and sense of coherence(t=4.33, p<.001) and the statistical power was 60.4%. Thus, a nursing intervention program which is focused on a sense of coherence could promote health behavior compliance in patients with stroke.

Experimental Study on DEM Extraction Using InSAR and 3-Pass DInSAR Processing Techniques (InSAR 및 3-Pass DInSAR 처리기법을 적용한 DEM 추출에 대한 실험 연구)

  • Bae, Sang-Woo;Lee, Jin-Duk
    • The Journal of the Korea Contents Association
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    • v.7 no.3
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    • pp.176-186
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    • 2007
  • As SAR data have the strong point that is not influenced by weather or light amount in comparison with optical sensor data, they are highly useful for temporary analysis and can be collected in time of unforeseen circumstances like disaster. This study is to extract DEM from L-band data of JERS-1 SAR imagery using InSAR and DInSAR processing techniques. As a result of analyzing the extracted coherence and interferogram images, it was shown that the DInSAR 3-pass method produces more suitable coherence values than the InSAR method. The accuracies of DEM extracted from the SAR data were evaluated by employing the DEM derived from the digital topographic maps of 1:5000 scale as reference data. And it was ascertained that baselines between antenna locations largely affect the accuracy of extracted DEM.

Analysis of a fixed source-to-receiver underwater acoustic communication channel parameters in shallow water (송수신기가 고정된 천해 수중음향통신 채널 매개변수 해석)

  • Bae, Minja;Park, Jihyun;Yoon, Jong Rak
    • The Journal of the Acoustical Society of Korea
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    • v.38 no.5
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    • pp.494-510
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    • 2019
  • Underwater acoustic communication channel parameters consist of impulse response, delay spreading, scattering function, coherence bandwidth, frequency selective fading, coherence time and time variant magnitude fading statistics on which communication system modem and channel coding are designed. These parameters are influenced by sound velocity profile, platform motion and sea surface roughness in given acoustical oceanography condition. In this paper, channel model based on phasor, channel simulator, measurement and analysis method of channel parameters are given in a fixed source-to-receiver system and the parameters are analyzed using shallow water experimental data. For two different source-to-receiver ranges of 300 m and 600 m, the parameters are characterized by three multipaths such as a direct, a surface reflection path with time variant scattering and a bottom reflection path. The results present a channel modelling method of a fixed source source-to-receiver system, channel parameters measurement and analysis methods and a system design and performance assessment method in shallow water.

A study of the transfer characteristics of pressure waves using two-port network analysis in exhaust system of engine (양단자 회로망 분석을 이용한 기관배기계의 압력파 전달특성에 관한 연구)

  • 이준서;유병구;차경옥
    • Journal of Advanced Marine Engineering and Technology
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    • v.22 no.1
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    • pp.77-84
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    • 1998
  • Based on experimental analysis, the characteristics of pulsating pressure wave propagation is clarified by testing of 4-stroke gasoline engine. The pulsating pressure wave in exhaust system is generated by pulsating gas flow due to working of exhaust valve. The pulsating pressure wave is closely concerned to the loss of engine power according to back pressure and exhaust noise. It is difficult to exactly calculate pulsating pressure wave propagation in exhaust system because of nonlinear effect. Therefore, in the first step for solving these problems, this paper contains experimental model and analysis method which are applied two-port network analysis. Also, it shows coherence function, frequency response function, back pressure, and gradient of temperature in exhaust system.

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Coherent Analysis of HVAC Using the Multi-Dimensional Spectral Analysis (다차원 스펙트럼 해석법을 이용한 자동차 공조시스템의 기여도분석)

  • Hwang, Dong-Kun;Oh, Jae-Eung;Lee, Jung-Youn;Kim, Sung-Soo
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.11a
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    • pp.999-1004
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    • 2004
  • In this study, we identify contribution of structure-borne-noise of vehicle HVAC system using Multi-Dimensional spectral analysis (MDSA) method. Firstly, to identify the applicability of MDSA method, the case of HVAC system was modeled with four input / single output system. The four inputs which is given vibration data is composed of blower, evaporator, heater and duct. The single output is noise data from driver's seat. When the blower motor is operating, we analyze the contributions of four input / single output. As a result of experiment, we identify efficiency of systems modeled with four input / single output through ordinary coherence function (OCF) and multiple coherence function (MCF).

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Period Detection of Randomness Ultrasonic Signal Occurred Repeatedly by a Tire Damage (타이어 손상에 의해 반복적으로 발생하는 랜덤성 초음파 신호의 주기검출)

  • Jung, Sun-Yong;Kang, Dae-Soo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.1
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    • pp.251-258
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    • 2013
  • We studied it about ways to detect damage of a tire about randomness ultrasonic signal which occurs repeatedly while rub a tire of driving car and a road surface. The signal randomness is decreased through the preprocess of short-time energy calculation and the average value of coherence function is used by the normalization expression of the signal randomness. The process limit that can be decide on the dominant period of a signal using the coherence threshold is analyzed and the algorithm to decide the dominant period is proposed by setting up the -3dB threshold of the maximum value on the power spectrum.

Curriculum Coherence and Item Completeness in the Items which Preservice Teachers Developed (수학 예비교사가 개발한 평가 문항의 교육과정 충실도와 문항 완성도)

  • Kim, Sun Hee
    • School Mathematics
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    • v.14 no.4
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    • pp.517-529
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    • 2012
  • Assessment in the school should be done consistently in accordance with the national curriculum. This study analyzed the process that preservice teachers developed the question items. The preservice teachers already equipped with the knowledge about the curriculum, didn't reflect it to items at first. However, in the review and modification process with colleague discussions, they get the curriculum coherence faithfully. And the item completeness gets higher such as to conform to the item intent, to help the students easily understand the item and to have the consistency between items.

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