• Journal of Life Science
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• v.24 no.3
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• pp.242-251
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• 2014

The objective of this study was to isolate a photosensitizer from Pueraria thunbergiana leaves that induces apoptosis in SK-HEP-1 cells. Column chromatography and thin layer chromatography were used to isolate active compounds from extracts of P. thunbergiana leaves. The structures of the isolated compounds were determined by 1D-NMR, 2D-NMR, and FAB-mass spectroscopy. A substance, named M4-3, was purified from the leaves of P. thunbergiana using various chromatography methods, and the absorbance of the substance was measured. The absorbance was highest at 410 nm, suggesting that the M4-3 substance was a different compound from chlorophyll a and b, which absorb at 410, 502, 533, and 607 nm. Further analyses revealed that the M4-3 compound was a $13^2$-hydoxy pheophorbide, a methyl ester with a molecular weight of 662. M4-3 was identified as a derivative compound of pheophorbide, with a structure that magnesium comes away from the porphyrin ring. The results of the analysis of the cytotoxicity of the M4-3 substance against the SK-HEP-1 cells revealed that it inhibited rates of cell growth by 40% and 80% at a concentration of 0.04 ${\mu}M$ and 0.08 ${\mu}M$, respectively. The M4-3 compound was found to be a photosensitizer for cytotoxicity because it was appeared only in light condition as examining activity in different irradiation conditions (light condition and nonlight condition) under the same concentration. Analysis of morphological changes in the cells following cell death induced by exposure to the M4-3 substance reveled representative phenomena of apoptosis (nuclear condensation, vesicle formation, and fragmentation of DNA). The induction of apoptosis was attributed to the compound's photodynamic activity.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.2
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• pp.39-44
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• 2020

Recently, numerous researches are being conducted in flexible substrate to apply to wearable devices. Particularly, Conductive substrate researches that can implement the wearable devices on clothing are massive. In this study, we formed fiber substrate spraying CNT and Pd mixed solution on it and plated metal layer with electroless plating. Used SEM equipment and EDS analysis to analysis structure of the plated fiber substrate and discovered Ni layer was created. For check electrical properties, mapping was performed to check surface resistance and distribution of resistance of electroless plated fiber substrate with 4-point probe. It was confirmed that conductivity was improved as the duration of electroless plating was increased, and it was found that distribution of resistance by surface location was uniform. Changes in resistance due to mechanical stress were measured through tensile, bending, and twisting tests. As a result, it was confirmed that resistance change of flexible substrate gradually disappeared as plating time increased. Using UTM (Universal testing machine), it was analyzed mechanical properties of the electroless plated substrate with respect to changes in plating time were improved. In the case of conductive fiber substrate in which electroless plating was performed for 2 hours, tensile strength was increased by 16 MPa than fiber substrate. Based on these results, we found that Ni-CNT-Fabric flexible substrate is adequate for clothing-intergrated conductive substrate and we positively expect that this experiment shows flexible substrate can adapt to and develop not only a wearable device technology but also other fields needing flexibility such as battery, catalyst and solar cell.

• Management & Information Systems Review
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• v.36 no.2
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• pp.157-185
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• 2017

This study was carried out with the attention that the concept of entrepreneurial orientation has been applied at various levels of CEO, employee, management, and organization as a whole. The differences between these concepts were examined by discriminant validity and convergence validity, and the causal relationship between these concepts and performance was analyzed. A total of 96 questionnaires were collected and analyzed. The results show that CEO's entrepreneurial orientation, employee's entrepreneurial orientation, manager's entrepreneurial orientation and organizational entrepreneurial orientation have convergent validity and discriminant validity, and that these variables have different effects on the firm 's innovation performance and financial performance. In the analysis of the mediating effect, when the variables of all levels were put into a single variable, the innovation performance mediates between the entrepreneurial orientation and the financial performance in all variables. However, when all variables are applied simultaneously, innovation performance has mediating effect only on the relationship between organizational entrepreneurship orientation and financial performance. This shows that there is a conceptual difference according to applied level. As a result of the analysis of the causal relationship by the application level of entrepreneurial orientation, it is found that causality is formed among the entrepreneurial orientation variables. In particular, CEO's entrepreneurial orientation influences employee's entrepreneurial orientation, manager's entrepreneurial orientation, and organization's entrepreneurial orientation, and again, employee's entrepreneurial orientation and managerial entrepreneurial orientation form a causal relationship that influences organization's entrepreneurial orientation. In the relationship between innovation performance and financial performance, CEO's entrepreneurial orientation, organization's entrepreneurial orientation, and manager's entrepreneurial orientation are influencing innovation performance, and the only variables influencing financial performance are organization's entrepreneurial orientation. In conclusion, the limitations of the study and its future direction are presented.

• Journal of The Korean Association For Science Education
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• v.35 no.1
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• pp.159-167
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• 2015

RI-Biomics is a promising radiation convergence technology that combines radiation with bio science as new growth power technology. Many developed countries are focusing active support and constant exertion to dominate the RI-Biomics market in advance. In order to achieve global leadership in the RI-Biomics field, we need more highly advanced technologies and professional manpower. In fact, we have less manpower compared to technology we currently hold. In this study, we established a basic infrastructure to train professional manpower in the RI-Biomics field by developing/operating optimum training program through expert interviews and survey. The developed program has four organized sections to understand overall procedure of RI-Biomics. To evaluate our training program, we performed test operations with eight students who have a major related to RI-Biomics for three weeks in KARA (Seoul) and KAERI (Jung-eup). In detail, radioisotope usage and safety management were conducted for one week as basic course, RI-Biomics application technology was conducted for two weeks as professional course. To verify performance results of training program, we conducted to journal research, daily reports, and survey on participants. The results show a high level of satisfaction with training programs and continuous intention of involvement in our program. We also need to develop an intensive course to train high-quality human resources and to operate training program continuously. This training program will be used as basic materials for the development of RI-Biomics curriculum for university. Hence, we will expect that our training program contributes in training a professional manpower and develop RI-Biomics technology.

• Cartoon and Animation Studies
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• s.36
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• pp.469-491
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• 2014

Webtoon has developed the method that makes it possible to express sound visually. Also we can also hear sound in webtoon through the development of web technology. It is natural that we analyze the sound that we can hear, but we can also analyze the sound that we can not hear. This study is based on 'dual code' in cognitive psychology. Cartoonists can make visual expression on the basis of auditive impression and memory, and readers can recall the sound through the process of memory and memory-retrieval. This study analyzes both audible sound and inaudable sound. Concise analysis owes the method to film sound theory. Three main factor, Volume, pitch, and tone are recognized by frequency in acoustics. On the other hand they are expressed by the thickness and site of line and image of sound source. The visual expression of in screen sound and off screen sound is related to the frame of comics. Generally the outside of frame means off sound, but some off sound is in the frame. In addition, horror comics use much sound for the effect of genre like horror film. When analyzing comics sound using this kinds of the method film sound analysis, we can find that webtoon has developed creative expression method comparing with simple ones of early comics. Especially arranging frames and expressing sound following and vertical moving are new ones in webtoon. Also types and arrangement of frame has been varied. BGM is the first in using audible sound and recently BGM composed mixing sound effect is being used. In addition, the program which makes it possible for readers to hear sound according to scroll moving. Especially horror genre raise the genre effects using this technology. Various methods of visualizing sound are being created, and the change shows that webtoon could be the model of convergence in contents.

• Korean Journal of Remote Sensing
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• v.37 no.5_3
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• pp.1447-1460
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• 2021

Urbanization increases the amount of impervious surface and artificial heat emission, resulting in urban heat island (UHI) effect. Local climate zones (LCZ) are a classification scheme for urban areas considering urban land cover characteristics and the geometry and structure of buildings, which can be used for analyzing urban heat island effect in detail. This study aimed to examine the UHI effect by urban structure in Suwon and Daegu using the LCZ scheme. First, the LCZ maps were generated using Landsat 8 images and convolutional neural network (CNN) deep learning over the two cities. Then, Surface UHI (SUHI), which indicates the land surface temperature (LST) difference between urban and rural areas, was analyzed by LCZ class. The results showed that the overall accuracies of the CNN models for LCZ classification were relatively high 87.9% and 81.7% for Suwon and Daegu, respectively. In general, Daegu had higher LST for all LCZ classes than Suwon. For both cities, LST tended to increase with increasing building density with relatively low building height. For both cities, the intensity of SUHI was very high in summer regardless of LCZ classes and was also relatively high except for a few classes in spring and fall. In winter the SUHI intensity was low, resulting in negative values for many LCZ classes. This implies that UHI is very strong in summer, and some urban areas often are colder than rural areas in winter. The research findings demonstrated the applicability of the LCZ data for SUHI analysis and can provide a basis for establishing timely strategies to respond urban on-going climate change over urban areas.

• Journal of radiological science and technology
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• v.44 no.5
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• pp.525-534
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• 2021

In order to provide high-quality medical services to the public and contribute to the improvement of public health, it is necessary to enact an independent law according to the work of radiological technologists. Therefore, this study intends to review the regulations related to radiographers in the Medical Service Technologists, etc. Act. and to present opinions and directions for enactment of individual laws for radiological technologists. An online survey was conducted to 15,000 radiological technologists working in medical institutions and education sites in Korea; 1,027 people (6.85%) responded. The questionnaire consisted of 3 questions on demographic characteristics, 5 questions on the scope of work, and 12 questions on the revision of the Medical Service Technologists, etc. Act. and the establishment of the Radiological Technologist Independent Act. Reliability and factor analysis were performed on 9 questions measured on a Likert 5-point scale in "Revision of the Medical Service Technologists, etc. Act. and the establishment of the Radiological echnologist Independent Act" among the questionnaire items. Reliability for the total 9 questions was Chronbach α=0.728. There was a high perception that the regulations related to radiological technologists were insufficient in the current Medical Service Technologists, etc. Act., and the perception that examinations performed by radiological technologists at medical institutions were included in medical practice was high. If the Radiological Technologist Independent Act is enforced, a high percentage of respondents said that they could receive legal protection through the institutionalization of the scope of work, that the status of radiological technologists would be improved, and the scope of work would be expanded. The response that the scope of work of radiological technologists should be included was the highest at 96.6%. In the analysis according to demographic characteristics, it was found that 96.7% of the respondents were agreed regardless of the factors. Radiological technologists will have to work hard to secure the public health by coping with new radiology devices, procedures and treatment methods. Therefore, as the results of this study, it is expected that the enactment and implementation of the Radiological Technologist Independent Act will contribute to the improvement of the quality of treatment for patients and to the public health.

• Korea Science and Art Forum
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• v.37 no.5
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• pp.215-226
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• 2019

This study analyzed the healing effect of the design elements of healing environment from the perspective of environmental stress, which is one of the contents of environmental psychology. By examining the objective healing effects of the design elements of the healing environment, this study attempted to prepare a theoretical basis for contributing to the construction of a systematic and systematic healing environment. This study consists of three phases. Firstly, three environmental stress theories (Attention Recovery Theory, Evolutionary Psychology, and Environmental Stress Model) were examined to review the academic basis of which the theoretical concept of the healing environment has been derived and developed. Second, we analyzed 16 previous research on the design elements of healing environment and used them as an analysis framework of this study. Thirdly, 11 foreign studies that proved the healing effects of healing environment design elements through objective research methods were considered and analyzed as an analysis framework, and the basis for applying design elements in constructing healing environment was prepared. The research results are as follows. First, the concept of healing environment was developed from Lazarus's psychological stress theory and Ulrich's theory of evolutionary psychology, suggesting that it can be used as one of the noninvasive healing tools that affect stress reduction. Second, the healing environment design elements could be divided into 15 factors and categorized as physical environment, psychological environment, and social environment, and it was found that most of them were mentioned and studied in the previous research in order of nature-friendly, aesthetic, and openness. Third, most of the previous research on the healing effects of the design elements of the healing environment were related to natural affinity and aesthetics, and it was found that the visual elements of the healing environment could affect the actual stress reduction.

• Science of Emotion and Sensibility
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• v.21 no.4
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• pp.63-76
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• 2018

The purpose of this study was to investigate the effect of contact type textile electrode structure on heart activity signal acquisition for smart healthcare. In this study, we devised six contact type textile electrodes whose electrode size and configuration were manipulated for measuring heart activity signals using computerized embroidery. We detected heart activity signals using a modified lead II and by attaching each textile electrode to the chest band in four healthy male subjects in a standing static posture. We measured the signals four times repeatedly for all types of electrodes. The heart activity signals were sampled at 1 kHz using a BIOPAC ECG100, and the detected original signals were filtered through a band-pass filter. To compare the performance of heart activity signal acquisition among the different structures of the textile electrodes, we conducted a qualitative analysis using signal waveform and size as parameters. In addition, we performed a quantitative analysis by calculating signal power ratio (SPR) of the heart activity signals obtained through each electrode. We analyzed differences in the performance of heart activity signal acquisition of the six electrodes by performing difference and post-hoc tests using nonparametric statistic methods on the calculated SPR. The results showed a significant difference both in terms of qualitative and quantitative aspects of heart activity signals among the tested contact type textile electrodes. Regarding the configurations of the contact type textile electrodes, the three-dimensionally inflated electrode (3DIE) was found to obtain better quality signals than the flat electrode. However, regarding the electrode size, no significant difference was found in performance of heart signal acquisition for the three electrode sizes. These results suggest that the configuration method (flat/3DIE), which is one of the two requirements of a contact type textile electrode structure for heart activity signal acquisition, has a critical effect on the performance of heart activity signal acquisition for wearable healthcare. Based on the results of this study, we plan to develop a smart clothing technology that can monitor high-quality heart activity without time and space constraints by implementing a clothing platform integrated with the textile electrode and developing a performance improvement plan.

• Journal of Digital Convergence
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• v.19 no.7
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• pp.57-70
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• 2021

As COVID-19 spreads, people's interest in smart learning that can do non-face-to-face learning is increasing nowadays. In this study, we aim to empirically analyze how users' thoughts on COVID-19 and the information quality and system quality of smart learning systems affect users' acceptance of smart learning and examine the effect of perceived sensitivity and severity of COVID-19 on the satisfaction and use of smart learning through concerns about the risk of transmission. In addition, we examined the influence of information quality composed of content quality and interaction quality and system quality composed of system accessibility and functionality on the use of smart learning through user satisfaction. To verify the validity of the proposed model, we conducted a survey on 334 users with experience in using smart learning, and performed the analysis using Smart PLS 3.0. According to the analysis results, among information quality and system quality, only functionality has a positive (+) effect on the satisfaction of smart learning, and satisfaction has a positive (+) effect on the usage behavior. However, it is found that accessibility among system quality do not affect satisfaction, and concern about the risk of transmission has a negative effect on satisfaction. This study can provide meaningful guidelines to researchers when researching smart learning to support students' learning in a pandemic situation of a new infectious disease, such as COVID-19. It will also be able to provide useful implications for educational institutions and companies related to smart learning.