• Journal of the Korean earth science society
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• v.44 no.1
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• pp.79-89
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• 2023

The purpose of this study was to investigate the effects of engineering design-based ocean cleanup classes on STEAM attitudes and creative engineering problem-solving dispositions. Furthermore, during this process, we tried to determine interesting points that students encountered in engineering design-based classes. For this study, a science class with six lessons based on engineering design was developed and reviewed by a professor who majored in engineering design, along with five engineering design experts with a master's degree or higher. The subject of the class was selected as the design and implementation of scientific and engineering measures to reduce marine pollution based on the method implemented in an actual Ocean Clean-up Project. The engineering design process utilized the engineering design model presented by NGSS (2013), and was configured to experience redesign through the optimization process. To verify effectiveness, the STEAM attitude questionnaire developed by Park et al. (2019) and the creative engineering problemsolving propensity test tool developed by Kang and Nam (2016) were used. A pre and post t-test was used for statistical analysis for the effectiveness test. In addition, the contents of interesting points experienced by the learners were transcribed after receiving descriptive responses, and were analyzed and visualized through degree centrality analysis. Results confirmed that engineering design in science classes had a positive effect on both STEAM attitude and creative engineering problem-solving disposition (p< .05). In addition, as a result of unstructured data analysis, science and engineering knowledge, engineering experience, and cooperation and collaboration appeared as factors in which learners were interested in learning, confirming that engineering experience was the main factor.

• Information Systems Review
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• v.21 no.4
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• pp.175-195
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• 2019

This study conducted both big data and netnography analysis to analyze consumer needs and behaviors of online consumer community. Big data analysis is easy to identify correlations, but causality is difficult to identify. To overcome this limitation, we used netnography analysis together. The netnography methodology is excellent for context grasping. However, there is a limit in that it is time and costly to analyze a large amount of data accumulated for a long time. Therefore, in this study, we searched for patterns of overall data through big data analysis and discovered outliers that require netnography analysis, and then performed netnography analysis only before and after outliers. As a result of analysis, the cause of the phenomenon shown through big data analysis could be explained through netnography analysis. In addition, it was able to identify the internal structural changes of the community, which are not easily revealed by big data analysis. Therefore, this study was able to effectively explain much of online consumer behavior that was difficult to understand as well as contextual semantics from the unstructured data missed by big data. The big data-netnography integrated model proposed in this study can be used as a good tool to discover new consumer needs in the online environment.

• Journal of Food Hygiene and Safety
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• v.25 no.1
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• pp.43-48
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• 2010

This research was conducted to know application of Photostimulated luminescence (PSL) and Thermoluminesce(TL) methods by irradiation dose for leaching tea, sauces and starch approved in Korea. Leaching tea, sauces and starch powder were treated with $^{60}Co$ gamma ray at dose 0~10 kGy for detection trial whether they are irradiated or not by measuring PSL and TL for whole samples. PSL values were less than threshold value 700 and were, negative for non-irradiated samples but more than 5,000 and were positive for irradiated ones. PSL results of leaching tea and sauces showed the correct identification for non-irradiated and irradiated samples, respectively except starch samples. To enhance the reliability of the TL result, the first glow curve (TL1) was compared with the second glove curve (TL2) obtained after a re-irradiation step at 1 kGy. The TL ratio ($TL_1/TL_2$) was in good agreement with the reported TL threshold for both the non-irradiated (< 0.1) and irradiated (> 0.1) samples. TL results of leaching tea, sauces, starch showed the correct identification for non-irradiated and irradiated samples, respectively. This study was performed to know application of PSL and TL methods for leaching tea, sauces and starch, and the methods were able to detect the irradiation products.

• Korean Journal of Remote Sensing
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• v.38 no.6_2
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• pp.1723-1735
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• 2022

Landslides are one of the most prevalent natural disasters, threating both humans and property. Also landslides can cause damage at the national level, so effective prediction and prevention are essential. Research to produce a landslide susceptibility map with high accuracy is steadily being conducted, and various models have been applied to landslide susceptibility analysis. Pixel-based machine learning models such as frequency ratio models, logistic regression models, ensembles models, and Artificial Neural Networks have been mainly applied. Recent studies have shown that the kernel-based convolutional neural network (CNN) technique is effective and that the spatial characteristics of input data have a significant effect on the accuracy of landslide susceptibility mapping. For this reason, the purpose of this study is to analyze landslide vulnerability using a pixel-based deep neural network model and a patch-based convolutional neural network model. The research area was set up in Gangwon-do, including Inje, Gangneung, and Pyeongchang, where landslides occurred frequently and damaged. Landslide-related factors include slope, curvature, stream power index (SPI), topographic wetness index (TWI), topographic position index (TPI), timber diameter, timber age, lithology, land use, soil depth, soil parent material, lineament density, fault density, normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) were used. Landslide-related factors were built into a spatial database through data preprocessing, and landslide susceptibility map was predicted using deep neural network (DNN) and CNN models. The model and landslide susceptibility map were verified through average precision (AP) and root mean square errors (RMSE), and as a result of the verification, the patch-based CNN model showed 3.4% improved performance compared to the pixel-based DNN model. The results of this study can be used to predict landslides and are expected to serve as a scientific basis for establishing land use policies and landslide management policies.

• The Journal of the Korea Contents Association
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• v.15 no.11
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• pp.313-321
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• 2015

To minimize CT examination for Hip FAI diagnosis and operation plan. also, whether the MRI 3D images can replace Hip Clock face image was evaluated when performing Hip FAI MRI by using additional 3D image. This study analyzed Hip MRI and 3D Hip CT images of 31 patients in this hospital. For the purpose of evaluating the images, one orthopedic surgeon and one radiology specialist reconstructed Clock face, at MR and CT modality, by superior 12 o'clock, labrum front 3 o'clock, and the other side 9 o'clock, centering on Hip joint articular transverse ligament 6 o'clock. Afterwards, by the Likert Scale 5 point scale (independent t-test p<0.005), this study evaluated the check-up of A. retinacular vessel, B. head neck junction at 11 o'clock, A. Epiphyseal line, B. Cam lesion at 12 o'clock, and Cam lesion, Posterior Cam lesion at 1,2,3 and 4 o'clock. As for the verification of reliability among observers, this study verified coincidence by Cohen's weighted Kappa verification. As a result of Likert scale for the purpose of qualitative evaluation about the image, 11 o'clock A. retinacular vessel MR average was $3.69{\pm}1.0$ and CT average was $2.8{\pm}0.78$. B. head neck juncton didn't have a difference between two observers (p <0.416). 12 o'clock A. Epiphyseal line MR average was $3.54{\pm}1.00$ and CT average was $4.5{\pm}0.62$(p<0.000). B. Cam lesion didn't have a difference between two observers (p <0.532). 1,2,3,4 Cam lesion and Posterior Cam lesion were not statistically significant (p <0.656, p <0.658). As a result of weighted Kappa verification, 11 o'clock A.retinacular vessel CT K value was 0.663 and the lowest conformity. As a result of coincidence evaluation on respective item, a very high result was drawn, and two observers showed high reliability.

• Journal of Global Scholars of Marketing Science
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• v.18 no.4
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• pp.217-244
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• 2008

Consumers' overall satisfaction on a specific library use is inferred to be primarily accrued from their performance perception and use satisfaction on the library information service system as recent information technology is being rapidly improved and more libraries are being equipped with advanced information technologies. However, prior research has been conducted only on general library service quality and visitors' satisfaction, leaving the important aspects of visitors' library use and information performance perception. Thus, the objectives of this research are to examine the effect of library use patterns such as general visit for book reading and more professional information search, coupled with service quality, on the library users' performance perception on the information system that in turn, affects library use satisfaction on the same information system. More specifically, this study examines whether library visitors perceive differenltly the information system performance according to their library use patterns such that professional library users may have less positive on information system service due to their higher expectation or more positive perception on it due to variety of information uses and positive judgment on advanced information system. Next, three dimensions of service quality, consisting of interaction, outcome, and physical evidence quality in visitors' library use situations, are hypothesized to affect performance perception on library information system. Thirdly, the performance perception on library information system is hypothesized to influence the system use satisfaction while these two constructs are to affect visitors' overall satisfaction. we develop the following research model in accordance with the above theoretical reasoning. All variables used in this study(General Use Patterns, Professional Use Patterns, Interaction Quality, Outcome Quality, Physical Evidence Quality, Information Performance Perception, Information Use Satisfaction, Overall Satisfaction) were defined operationally based on the underlying prior studies. A survey was conducted with prepared questionnaires to about 400 visitors of a specific university library. Among them, 353 proper questionnaires were finally used for the analyses. Two-step approach was used to test the hypotheses. First, confirmatory factor analysis was conducted to guarantee the validity and reliability of variables. The results showed that all variables had not only convergent and discriminant validity, but also reliability. Then, research model was examined with a structural equation using LISREL 8.30 version. The fitness of the research model was found to be within the acceptable level. The findings of this study are as follows. The professional library use pattern was found to affect the users' performance perception on the library information system while the general library use pattern was not. Second, three dimensions of service quality (interaction, outcome, physical evidence) were found to influence the information system performance respectively while none of them was not to information use satisfaction. Third, library users' performance perception on the information system operation was found to affect the information system use satisfaction, both of which also influence users' overall satisfaction of the library. The findings of this study suggest that contemporary libraries strengthen their advanced information system operation in a way of user orientation and more importantly maximize their visitors' utilization of information system, accompanying proper material and various program development. This study conceptualized the new constructs of library users' performance perception on the information system and information use satisfaction which could better explain library users' overall satisfaction. Thus, furture study related with library service could utilize the constructs of information system performance and satisfaction as well as the variety of library use patterns in the users' viewpoints.

• CRM연구
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• v.2 no.2
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• pp.1-19
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• 2009

In an attempt to explore the consumption behaviors of customers regarding ethnic food restaurants the present study examined the effects of consumer characteristics, accessibility of ethnic food restaurants, product characteristics, and social factors on the customer behavior towards ethnic food restaurants, and further investigated the causal relationship between the customer behavior and his or her intent to reuse. A questionnaire survey was conducted approximately for a month with domestic consumers who had tried foreign cuisines. A total of 230 questionnaires were distributed and 215 questionnaires were collected, of which 210 were used in the final analysis excluding five due to inadequate responses. The finding of the study were as follows. First, of the consumers' lifestyles category the gourmet oriented did not yield significant effect on subjective norm or other consumption behavior, whereas the trend oriented had noticeable influence on both factors. Second, while consumers' diversity-seeking characteristic did not affect subjective norm, it affected consumption behavior of ethic food restaurants. The results seem to indicate that the diversity-seeking characteristic is more to one's individual attributes, rather than being influenced by others. Third, ethnic food restaurant's consumption accessibilities strongly influenced the subjective norm, suggesting that in using the ethnic food restaurants, the more convenient the accessibility is, the higher the possibility of use from influenced reference group. However, when consumers previously had not been exposed to ethnic cuisines, convenient accessibility was not able to overcome the barriers of consumer reluctance, nor directly shape positive behaviors. Fourth, while national uniqueness of ethnic food did not affect subjective norm, the uniqueness did have positive impact on consumption behavior of foreign ethnic food restaurants. Fifth, consumer's subjective norm positively influenced both consumption behavior of ethnic food restaurants and their intent for future use. Lastly, consumption behavior toward foreign ethnic food restaurants positively influenced consumer's intent for future use, indicating that it would be most imperative and effective to first help reinforce positive attitude in oder to encourage a more use of ethnic food restaurants.

• Journal of Intelligence and Information Systems
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• v.23 no.3
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• pp.119-138
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• 2017

Recently, SNS has become an important channel for marketing as well as personal communication. However, cybercrime has also evolved with the development of information and communication technology, and illegal advertising is distributed to SNS in large quantity. As a result, personal information is lost and even monetary damages occur more frequently. In this study, we propose a method to analyze which sentences and documents, which have been sent to the SNS, are related to financial fraud. First of all, as a conceptual framework, we developed a matrix of conceptual characteristics of cybercriminality on SNS and emergency management. We also suggested emergency management process which consists of Pre-Cybercriminality (e.g. risk identification) and Post-Cybercriminality steps. Among those we focused on risk identification in this paper. The main process consists of data collection, preprocessing and analysis. First, we selected two words 'daechul(loan)' and 'sachae(private loan)' as seed words and collected data with this word from SNS such as twitter. The collected data are given to the two researchers to decide whether they are related to the cybercriminality, particularly financial fraud, or not. Then we selected some of them as keywords if the vocabularies are related to the nominals and symbols. With the selected keywords, we searched and collected data from web materials such as twitter, news, blog, and more than 820,000 articles collected. The collected articles were refined through preprocessing and made into learning data. The preprocessing process is divided into performing morphological analysis step, removing stop words step, and selecting valid part-of-speech step. In the morphological analysis step, a complex sentence is transformed into some morpheme units to enable mechanical analysis. In the removing stop words step, non-lexical elements such as numbers, punctuation marks, and double spaces are removed from the text. In the step of selecting valid part-of-speech, only two kinds of nouns and symbols are considered. Since nouns could refer to things, the intent of message is expressed better than the other part-of-speech. Moreover, the more illegal the text is, the more frequently symbols are used. The selected data is given 'legal' or 'illegal'. To make the selected data as learning data through the preprocessing process, it is necessary to classify whether each data is legitimate or not. The processed data is then converted into Corpus type and Document-Term Matrix. Finally, the two types of 'legal' and 'illegal' files were mixed and randomly divided into learning data set and test data set. In this study, we set the learning data as 70% and the test data as 30%. SVM was used as the discrimination algorithm. Since SVM requires gamma and cost values as the main parameters, we set gamma as 0.5 and cost as 10, based on the optimal value function. The cost is set higher than general cases. To show the feasibility of the idea proposed in this paper, we compared the proposed method with MLE (Maximum Likelihood Estimation), Term Frequency, and Collective Intelligence method. Overall accuracy and was used as the metric. As a result, the overall accuracy of the proposed method was 92.41% of illegal loan advertisement and 77.75% of illegal visit sales, which is apparently superior to that of the Term Frequency, MLE, etc. Hence, the result suggests that the proposed method is valid and usable practically. In this paper, we propose a framework for crisis management caused by abnormalities of unstructured data sources such as SNS. We hope this study will contribute to the academia by identifying what to consider when applying the SVM-like discrimination algorithm to text analysis. Moreover, the study will also contribute to the practitioners in the field of brand management and opinion mining.

• Journal of Life Science
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• v.33 no.2
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• pp.169-175
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• 2023

As a protective defensive mechanism against ultraviolet (UV) light exposure in skin tissue, melanocytes produce the pigment melanin. Tyrosinase plays a key role in melanin production in melanocytes. However, the overproduction of melanin can lead to lesions, such as freckles and dark spots. Thus, it is clinically important to find a modulating molecule to control melanogenesis by regulating tyrosinase expression and/or activity. It is known that catechin, a plant flavonoid, can reduce melano- genesis through the downregulation of tyrosinase expression. Here, we tested whether catechin derivatives isolated from the stem bark of Ulmus parvifolia have an effect on melanin production by regulating tyrosinase in mouse melanoma cells and in vitro mushroom tyrosinase. The catechin derivatives used in this study included C5A, C7A, C7G, and C7X. Treatments using these catechin derivatives reduced melanin production in mouse melanoma B16F10 cells in which melanogenesis was stimulated by α-MSH. Notably, the anti-melanogenic effects of catechin derivatives were similar to those of kojic acid, a well-known anti-melanogenic molecule. Both C5A and C7A directly inhibited the activity of tyrosinase isolated from mushrooms in vitro. Furthermore, our in silico computational simulation showed that these two compounds were expected to bind to the active site of tyrosinase, which is similar to kojic acid. In addition, all four catechin derivatives reduced tyrosinase protein expression. In summary, our results showed that catechin derivatives can reduce melanogenesis by regulating tyrosinase activity or expression. Thus, this study suggests that catechin derivatives isolated from U. parvifolia can be novel modulators of melanin production.

• Asia Marketing Journal
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• v.8 no.3
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• pp.41-74
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• 2006

It is frequently observed that consumers' behavior and performance in their weight control are greatly affected by the degree of self-control by the consumers themselves. In other words, effective weight control behavior is only possible when the consumers invest a substantial amount of endeavors and self-control. The present study empirically investigated the effect of the self-image congruence and subjective norm formed by self- concept reflected in weight control behavior on weight control attitude formation, actual behavior, and performance. For more in-depth research, rather than simply showing differences in performance based on self-control, the present study divided the subjects into high and low self-control groups for a comparative purpose. Based on empirical research employing general consumers and those who were engaged in an actual weight loss program at professional weight control centers as subjects, the study found the following results: First, for both high and low self-control groups, self-image congruence significantly affected attitude toward weight control, but not the actual weight control behavior. The results indicate that in weight control, the actual behavior must be preceded by the attitude. Second, subjective norm directly affected both attitude toward weight control, and behavior for the low self-control group while it affected the behavior only for the high self-control group. The results show that the lower self-control is, the more powerful the effect of referents is. Third, weight control attitude positively affected weight control behavior only for the high self-control group. Fourth, weight control behavior significantly affected the performance for both high and low self-control groups. Compared to the low group, the high self-control group showed more powerful effect of behavior, suggesting the crucial role of self-control in successful weight control. The results also imply that the role of referents is relatively more important for the low self-control group.