• Journal of the Korean Chemical Society
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• v.43 no.3
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• pp.340-350
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• 1999

This study was to analyze the articulation between chemistry contents of science textbooks at elementary and middle school level, to survey students ? perceptions on chemistry concepts, to establish guidelines for science textbooks that not only meet the needs of learners but also fit in a coherent way. In order to do this, we analyzed links of the aims and the organization of chemistry contents of elementary and middle school science textbooks, we also surveyed students' perceptions on chemistry concepts students had retained. The study revealed that the 6th middle school curriculum was almost a duplicate of the elementary school syllabus. And there was no interrelation between the organization of chemistry contents and the aim of the chapter which built up a logical picture of the world at a molecular level. It was also found that the lack of coherence between science textbooks in elementary and middle school was a major cause of student difficulty.

• Journal of Service Research and Studies
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• v.9 no.1
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• pp.1-16
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• 2019

This study analyzed Korean representative ideology to establish a service philosophy. As a follow - up study of the service philosophy consistency study of the Korean original idea, we searched for the coherence as the philosophy of the service age in the Korean representative ideology. The basic structure and operation model of service philosophy are presented, and the service philosophy of major korean ideology is derived. The philosophy of service can be presented by the structure of service and the operation of service. The essential characteristics of the service are relationship, interactivity, horizontality, and harmony, and the service structure that reflects this is the coexistence of products and services. Based on the discussion on the structure and operation of the service philosophy, the service philosophy synthesis of Korean representative ideology is presented. From the Silla era to the Koryo dynasty, the essence of Korean Buddhism thought is in line with the service philosophy, and it was found that Toegye and Yulgok to Dasan's thoughts are also consistent with service philosophy. In the future, we need further studies to refine the structure and operational principles of the service philosophy and to develop it into a big idea. In addition, it is necessary to follow up the service philosophy of Oriental representative ideology centering on Chinese and Indian philosophy. Ultimately, it is necessary to establish a service philosophy as the main philosophical thought and to establish a service philosophy as a desirable future economic and social philosophy.

• Korean Journal of Remote Sensing
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• v.34 no.6_1
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• pp.1143-1153
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• 2018

For TOPS InSAR processing, high-precision image co-registration is required. We propose an image co-registration method suitable for the TOPS mode by comparing the performance of cross correlation method, the geometric co-registration and the enhanced spectral diversity (ESD) matching algorithm based on the spectral diversity (SD) on the Sentinel-1 TOPS mode image. Using 23 pairs of interferometric pairs generated from 25 Sentinel-1 TOPS images, we applied the cross correlation (CC), geometric correction with only orbit information (GC1), geometric correction combined with iterative cross-correlation (GC2, GC3, GC4), and ESD iteration (ESD_GC, ESD_1, ESD_2). The mean of co-registration errors in azimuth direction by cross correlation and geometric matching are 0.0041 pixels and 0.0016 pixels, respectively. Although the ESD method shows the most accurate result with the error of less than 0.0005 pixels, the error of geometric co-registration is reduced to 0.001 pixels by repetition through additional cross correlation matching between the reference and resampled slave image. The ESD method is not applicable when the coherence of the burst overlap areas is low. Therefore, the geometric co-registration method through iterative processing is a suitable alternative for time series analysis using multiple SAR data or generating interferogram with long time intervals.

• Journal of the Korean earth science society
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• v.42 no.1
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• pp.88-101
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• 2021

The purpose of this study was to qualitatively examine the meaning of students' drawings in outdoor classes and modeling-based learning cycles. Ten students were observed in a gifted education center in Seoul. Under the theme of the Hantan River, three outdoor classes and three modeling activities were conducted. Data were collected to document all student activities during field trips and classroom modeling activities using simultaneous video and audio recording and observation notes made by the researcher and students. Please note it is unclear what this citation refers to. If it is the previous sentence it should be placed within that sentence's punctuation. Hatisaru (2020) Ddrawing typess were classified by modifying the representations in a learning context in geological field trips. We used deductive content analysis to describe the drawing characteristics, including students writing. The results suggest that students have symbolic images that consist of geologic concepts, visual images that describe topographical features, and affective images that express students' emotion domains. The characteristics were classified into explanation, generality, elaboration, evidence, coherence, and state-of-mind. The characteristics and drawing types are consecutive in the modeling-based learning cycle and reflect the students' positive attitude and cognitive scientific domain. Drawing is a useful tool for reflecting students' thoughts and opinions in both outdoor class and classroom modeling activities. This study provides implications for emphasizing the importance of drawing activities.

• The Journal of the Acoustical Society of Korea
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• v.41 no.2
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• pp.184-191
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• 2022

Underwater acoustic wave in shallow water is propagated through multipath that has a large delay spread causing Inter-Symbol Interference (ISI) and these characteristics deteriorate the performance in the communication system. In order to analyze the communication performance and investigate the correlation with multipath delay spread in a reverberant environment, an underwater acoustic communication experiment using Binary Phase-Shift Keying (BPSK) signals with symbol rates from 100 sym/s to 8000 sym/s was conducted in a 5 × 5 × 5 m³ water tank. The acoustic channels in a well-controlled tank environment had the characteristics of dense multipath delay spread due to multiple reflections from the interfaces and walls within the tank and showed the maximum excess delay of 40 ms or less, and the Root Mean Squared (RMS) delay spread of 8 ms or less. In this paper, the performances of Bit Error Rate (BER) and output Signal-to-Noise Ratio (SNR) were analyzed using four types of communication demodulation techniques. And the parameter, Symbol interval to Delay spread Ratio in reverberant environment (SDR_rev), which is the ratio of symbol interval to RMS delay spread in the reverberant environment is defined. Finally, the SDR_rev was compared to the BER and the output SNR. The results present the reference symbol rate in which high communication performance can be guaranteed.

• Journal of The Korean Ophthalmological Society
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• v.58 no.8
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• pp.960-967
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• 2017

Purpose: To compare the macular choroidal thickness in patients with thyroid-associated ophthalmopathy (TAO) with those with normal tension glaucoma (NTG). Methods: A total of 70 normal eyes, 74 eyes with TAO and 60 eyes with NTG were enrolled in this study. All patients underwent spectral-domain optical coherence tomography (SD-OCT) (Cirrus HD-OCT, Carl Zeiss Meditec Inc., Dublin, CA, USA). Macular choroidal thickness was assessed using enhanced depth imaging. The average macular choroidal thickness was defined as the average value of three measurements: at the fovea and at the points located 1.5 mm in the nasal and temporal directions from the fovea. Generalized estimating equations were used to uncover factors affecting the average macular choroidal thickness. Results: The average, superior and inferior quadrant retinal nerve fiber layer thicknesses were significantly thinner in the NTG group compared with the TAO and control groups (p < 0.001). The average macular choroidal thickness of the TAO group, NTG group and controls was $281.01{\pm}60.06{\mu}m$, $241.66{\pm}55.00{\mu}m$ and $252.07{\pm}55.05{\mu}m$, respectively, which were significantly different (p = 0.013). The subfoveal, nasal and temporal side choroidal thicknesses were significantly thinner in the NTG group compared with the TAO group (p = 0.014, 0.012 and 0.034, respectively). Subjects with TAO were associated with a thicker average macular choroidal thickness compared with the NTG group after adjusting for age, sex, spherical equivalent and intraocular pressure (${\beta}=32.61$, p = 0.017). Conclusions: Macular choroidal thickness was significantly thicker in patients with TAO compared with those with NTG. Further evaluation is required to determine if a thick choroid in subjects with TAO has any role in glaucomatous optic neuropathy.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.2
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• pp.153-160
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• 2015

The objective of this study is to construct the TPU aerodynamic database with wind tunnel test data of overall wind loads and responses on tall buildings. In this study, wind tunnel tests were conducted to investigate characteristics of wind forces and the effect of wind load combination by cross-correlation analysis among along-wind overturning moment, across-wind overturning moment and torsional moment on a tall building with various side ratios(D/B=0.33, 0.50, 0.77, 0.83, 0.91, 1.0, 1.1, 1.2, 1.3, 2.0 and 3.0) for different terrain roughnesses. The results of wind tunnel tests were compared with those of past literatures. As a result, there was no significant effects of changing of terrain roughnesses on moment coefficients and power spectral densities of across-wind overturning moment coefficients and torsional moment coefficients with various side ratios. Further, these results were good agreement with those of past literatures. From cross-correlation analysis, the across-wind overturning moment coefficients were highly correlated with the torsional moment coefficients. The results of this study will be helpful for practical designers in preliminary design stage.

• The Journal of the Korea Contents Association
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• v.20 no.4
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• pp.464-474
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• 2020

This study provides basic data for nursing intervention to increase self management of hemodialysis patients by identifying the relation among their illness perception, physiological indicators, and self management. The participants were 134 patients receiving hemodialysis at a general hospital in Seoul. Data were collected by using a structured questionnaire and medical records. The collected data were analyzed by using descriptive statistics, independent t-test, one-way ANOVA, Pearson correlation coefficient and multiple regression analysis with the SPSS/WIN 23.0 program. The significant factors influencing self-management of hemodialysis patients have been identified with 8 variables. The first one is registration for kidney transplantation (β=-.20, p=.034). Among sub items of illness perception are consequence (β=-.20, p=.031), treatment control (β=.19, p=.040), and illness coherence (β=-.18, p=.049). In addition, among physiological indicators are hematocrit (β=.38, p<.001), hemoglobin (β=.29, p=.005), BUN (β=-.25, p=.010), and phosphorous (β=.22, p=.033). These variables explained 26.3% for self-management of hemodialysis patients. In order for hemodialysis patients to improve their self-management, a concrete nursing intervention improving the treatment control among illness perception as well as improving the understanding of physical indicators needs to be provided.

• Korean journal of communication and information
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• v.62
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• pp.244-263
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• 2013

There have been enormous social impacts on many areas, including science journalism, since the so-called "Hwang Woo Suk" incident. Although wide demand for better science journalism has been aroused since then, but it is hard to find an evidence to prove we have reached the point. This study examines how major Korean newspapers report Unidentified Flying Objects in order to test if the level of science journalism had been elevated. As results, still it is a long road ahead to achieve the goals because most reports were taken from the international news agents or from the witnesses rather than scientific researches and analyses; terminologies used in the stories were ambiguous; follow-up stories were rare, the sources were usually pseudo-scientific, wanton errors in basic facts and coherence, and other problems were found. It could be suggested that the dependency on supplied news to be reduced, journalists who understand both science and journalism are required, inner regulations on science reporting to be established, correct quotations and fact-checks to be accomplished, fairness to be maintained within the boundary of normal science.

• Journal of Elementary Mathematics Education in Korea
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• v.11 no.2
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• pp.99-115
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• 2007

The purpose of this study was to look into whether this mathematising learning utilizing realistic context has an effect on the mathematical thinking. To solve the above problem, two 5th grade classes of D Elementary School in Seoul were selected for performing necessary experiments with one class designated as an experimental group and the other class as a comparative group. Throughout 17 times for six weeks, the comparative group was educated with general mathematics learning by mathematics and "mathematics practices," while the experimental group was taught mainly with mathematising learning using realistic context. As a result, to start with, in case of the experimental group that conducted the mathematising learning utilizing realistic coherence, in the analogical and developmental thoughts which are mathematical thoughts related to the methods of mathematics, in the thinking of expression and the one of basic character which are mathematical thoughts related to the contents of mathematics, and in the thinking of operation, the average points were improved more than the comparative group, also having statistically significant differences. The study suggested that it is necessary to conduct subsequent studies that can verify by expanding to each grade, sex and region, develop teaching methods suitably to the other content domains and purposes of figures, and demonstrate the effects. In addition to those, evaluation tools which can evaluate the mathematical thinking processes of children appropriately and in more diversified methods will have to be developed. Furthermore, in order to maximize mathematising for each group in each mathematising process, it would be necessary to make efforts for further developing realistic problem situations, works and work sheets, which are adequate to the characteristics of the upper and lower groups.