• Journal of the Korean School Mathematics Society
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• v.12 no.4
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• pp.545-562
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• 2009

Calculus is used in various parts of human life and the basis of social science such as economics and public administration. Yet that is still considered important in the field of science and technology only, and there have been a lot of disputes on that phenomenon. Fortunately, calculus is going to be taught as part of the academic high school second-year mathematics curriculum in and after 2010. Students who face calculus for the first time should be helped not to lose interest in differentiation learning, not to be apprehensive of it nor to avoid it. The purpose of this study was to examine the types of errors made by students in the course of solving differentiation problems in an effort to lay the foundation for differentiation education. A pilot test was conducted after generalized differentiation problems to which students were usually exposed were selected, and experts were asked to review the pilot test. And then a finalized test was implemented to make an error analysis according to an error type analysis framework to serve the purpose.

• Korean Journal of Cognitive Science
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• v.23 no.4
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• pp.425-455
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• 2012

Multi-dimensional verbal short-term memory mechanisms are largely divided into the phonological channel and the lexical-semantic channel. The former is called phonological short-term memory and the latter is called semantic short-term memory. Phonological short-term memory is further segmented into the phonological input buffer and the phonological output buffer. In this study, the language performance of each of three patients with similar levels of conduction aphasia was analyzed in terms of multi-dimensional verbal short-term memory. To this end, three patients with conduction aphasia were instructed to perform four different aspects of language tasks that are spontaneous speaking, repetition, spontaneous writing, and dictation in both word and sentence level. Moreover, the patients' phonological memories and semantic short-term memories were evaluated using digit span tests and verbal learning tests. As a result, the three subjects exhibited various types of performances and error responses in the four aspects of language tests, and the short-term memory tests also did not produce identical results. The language performance of three patients with conduction aphasia can be explained according to whether the defects occurred in the semantic short-term memory, phonological input buffer and/or phonological output buffer. In this study, the relations between language and multi-dimensional verbal short-term memory were discussed based on the results of language tests and short-term memory tests in patients with conduction aphasia.

• Korean Journal of Cognitive Science
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• v.19 no.1
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• pp.1-15
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• 2008

Analyzing of dependency relation among clauses is one of the most critical parts in parsing Korean sentences because it generates severe ambiguities. To get successful results of analyzing dependency relation, this task has been the target of various machine learning methods including SVM. Especially, kernel methods are usually used to analyze dependency relation and it is reported that they show high performance. This paper proposes an expression and a composit kernel for dependency analysis of Korean clauses. The proposed expression adopts a composite kernel to obtain the similarity among clauses. The composite kernel consists of a parse tree kernel and a liner kernel. A parse tree kernel is used for treating structure information and a liner kernel is applied for using lexical information. the proposed expression is defined as three types. One is a expression of layers in clause, another is relation expression between clause and the other is an expression of inner clause. The experiment is processed by two steps that first is a relation expression between clauses and the second is a expression of inner clauses. The experimental results show that the proposed expression achieves 83.31% of accuracy.

• Journal of Distribution Science
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• v.13 no.2
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• pp.105-112
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• 2015

Purpose - There is a recent social trend that is focused on the revitalization of business-founding. Business-founding now has an important impact on the progress of the national economy because of youth unemployment and an increase in baby-boom generation retirees. However, the support and infrastructure required for business-founding of the disabled are very insufficient. Since most supporting policies are on youth or middle-aged business-founding, business-founding by the disabled and the socially weak is losing competitiveness. Accordingly, this study diagnosed the issues by analyzing the current status of business-founding by the disabled and suggested a fostering direction for the advance of business-founding by the disabled. An idea for the founding of various business items is required for the competitiveness of business-founding by the disabled and the establishment of a growth-model based on marketing is required so that business-founding by the disabled would advance toward commercialization with growth potential. Research design, data, and methodology - Regarding the study method, the existing study literature on the status and issues in business-founding was mainly explored. In addition, the existing literature on the status and issues in business-founding by the disabled was also studied. The support on business-founding by the disabled by policy enforced by the 'Welfare Service Agency for the Disabled'and the support of related agencies including financial support on the commercialization of business-founding by the disabled were also examined. Results - Existing studies on business-founding by the disabled are very insufficient. It is very difficult to study a viable business-founding by the disabled fostering policy without thorough learning on the difficulties of business-founding by the disabled. Therefore, this study suggested a direction for the resolution of various issues such as market, funds, item, operational matters, and service by analyzing the difficulties in business-founding by the disabled until now. Particularly, this study suggested that building a commercialization model from the aspect of marketing strategy and the effort to change the growth aspect of the disabled into competitiveness are essential. Conclusions - This study examined the aspect of developing an item-development process for the growth and founding of disabled-owned businesses and the requirement of a government support system by multiple policies. Since the number of studies on business-founding by the disabled is very small, it is expected that this study would become an important study in the field of business-founding by the disabled. The revitalization of business-founding by the disabled substantially contributes to the progress of the state of the economy and continuous interest is required from the viewpoint of equal advance in the society. Success models in business-founding by the disabled should be created continuously and active publicizing of them to the disabled business-founders by analyzing the success cases would also be required. In addition, it is believed that a market entry strategy by way of a win-win strategy and cooperative relation with big companies should be also developed in the future.

• Korean Journal of Cognitive Science
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• v.23 no.1
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• pp.47-71
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• 2012

This study examined how students revised their writing after reciprocal peer review and how their revision activities were influenced by the review. Undergraduates in physics class wrote a laboratory reports, exchanged comments with peers, and revised their reports afterward based on the comments they received from their peers. The comparison between the original and the revised drafts showed that students were mainly concerned with micro-meaning revisions, focusing on making changes on individual words, clauses, and sentences. Revisions that dealt with macro-meaning of the texts were not as frequent. Giving and receiving comments influenced later revision activities. Receiving comments on micro-meaning of the texts led to a significant increase in both micro- and macro-meaning revisions. Receiving comments on macro-meaning of the texts, however, did not prompt relevant revision activities. Even when students engaged in macro revision, it was negatively related to writing performance gains in one subgroup, suggesting that even after peers point out macro-problems in their writing, students are not competent to solve the problems yet. The results of the study suggest that more efforts are needed to help them to understand and manipulate the macro-meaning structure of the texts.

• Korean Journal of Cognitive Science
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• v.21 no.2
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• pp.309-338
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• 2010

In this paper, we studied the brain-computer interface (BCI). BCIs help severely disabled people to control external devices by analyzing their brain signals evoked from motor imageries. The findings in the field of neurophysiology revealed that the power of $\beta$(14-26 Hz) and $\mu$(8-12 Hz) rhythms decreases or increases in synchrony of the underlying neuronal populations in the sensorymotor cortex when people imagine the movement of their body parts. These are called Event-Related Desynchronization / Synchronization (ERD/ERS), respectively. We implemented a BCI-based mouse interface system which enabled subjects to control a computer mouse cursor into four different directions (e.g., up, down, left, and right) by analyzing brain signal patterns online. Tongue, foot, left-hand, and right-hand motor imageries were utilized to stimulate a human brain. We used a non-invasive EEG which records brain's spontaneous electrical activity over a short period of time by placing electrodes on the scalp. Because of the nature of the EEG signals, i.e., low amplitude and vulnerability to artifacts and noise, it is hard to analyze and classify brain signals measured by EEG directly. In order to overcome these obstacles, we applied statistical machine-learning techniques. We could achieve high performance in the classification of four motor imageries by employing Common Spatial Pattern (CSP) and Linear Discriminant Analysis (LDA) which transformed input EEG signals into a new coordinate system making the variances among different motor imagery signals maximized for easy classification. From the inspection of the topographies of the results, we could also confirm ERD/ERS appeared at different brain areas for different motor imageries showing the correspondence with the anatomical and neurophysiological knowledge.

• Steel and Composite Structures
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• v.34 no.5
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• pp.743-767
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• 2020

Due to the impressive flexural performance, enhanced compressive strength and more constrained crack propagation, Fibre-reinforced concrete (FRC) have been widely employed in the construction application. Majority of experimental studies have focused on the seismic behavior of FRC columns. Based on the valid experimental data obtained from the previous studies, the current study has evaluated the seismic response and compressive strength of FRC rectangular columns while following hybrid metaheuristic techniques. Due to the non-linearity of seismic data, Adaptive neuro-fuzzy inference system (ANFIS) has been incorporated with metaheuristic algorithms. 317 different datasets from FRC column tests has been applied as one database in order to determine the most influential factor on the ultimate strengths of FRC rectangular columns subjected to the simulated seismic loading. ANFIS has been used with the incorporation of Particle Swarm Optimization (PSO) and Genetic algorithm (GA). For the analysis of the attained results, Extreme learning machine (ELM) as an authentic prediction method has been concurrently used. The variable selection procedure is to choose the most dominant parameters affecting the ultimate strengths of FRC rectangular columns subjected to simulated seismic loading. Accordingly, the results have shown that ANFIS-PSO has successfully predicted the seismic lateral load with R² = 0.857 and 0.902 for the test and train phase, respectively, nominated as the lateral load prediction estimator. On the other hand, in case of compressive strength prediction, ELM is to predict the compressive strength with R² = 0.657 and 0.862 for test and train phase, respectively. The results have shown that the seismic lateral force trend is more predictable than the compressive strength of FRC rectangular columns, in which the best results belong to the lateral force prediction. Compressive strength prediction has illustrated a significant deviation above 40 Mpa which could be related to the considerable non-linearity and possible empirical shortcomings. Finally, employing ANFIS-GA and ANFIS-PSO techniques to evaluate the seismic response of FRC are a promising reliable approach to be replaced for high cost and time-consuming experimental tests.

• Journal of Korean Library and Information Science Society
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• v.51 no.2
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• pp.1-21
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• 2020

The purpose of this study is to explore semantic characteristics of IFLA school library guidelines through network analysis. There are two versions, 2002 edition and 2015 revision of the guidelines. This study analyzed the 2002 edition and 2015 revision of the IFLA school library guidelines view point of semantic network, and compared characteristics of two versions. The keywords were to extracted from two texts, semantic network were composed based on co-occurrence relations with keywords. The centrality(degree centrality, closeness centrality, betweenness centrality) was analyzed from the network. In addition, this study conducted topic modeling analysis using LDA function of NetMiner4.0. The result of this study is following these. First, When comparing the centrality, the 'Program, Teaching, Reading, Inquiry, Literacy, Media' keyword was higher in the 2015 revision than in the 2002 edition. Second, 'Inquiry' in degree centrality and 'Achievement' in closeness centrality which were not included in the 2002 edition top-ranked keyword list, have new appeared in 2015 revision. third, As a result of the analysis of topic modeling, compared to the 2002 version, the importance of topics on programs and services, teaching and learning activities of librarian teacher, and media and information literacy is increasing in the 2015 revision.

• Journal of Distribution Science
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• v.14 no.8
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• pp.113-121
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• 2016

Purpose - This paper aims to examine the impact of buyer-supplier cooperation on suppliers' trust on buyers and the moderating role of buyers' governance mechanism between the sharing activities and trust. Research design, data, and methodology - An integrated research model is designed to materialize the research hypotheses. First, the impact of buyer-supplier cooperation is empirically analyzed by looking into how the sharing activities, in the field of information, resource, and knowledge, of buyer with supplier will affect the trust of supplier on buyer. Second, the moderating effect of contract-based governance mechanism of buyer is empirically analyzed. Third, the influence of trust on innovation performance of suppler is empirically analyzed. Results - Our findings provide supporting evidence for some of our hypotheses. First, all of the sharing activities are significantly influential, but in different degree, to trust of supplier. Second, contract-based governance mechanism of buyer have a moderating effect on the relationship between sharing activities and trust, positively in resource-sharing activities, negatively in information-sharing activities, not significant in knowledge-sharing activities. Third, supplier's trust on buyer positively affects supplier's own innovation performance. Conclusions - The strategies applied in supply chain management have become important as the competition among firms has shifted from competition between individual firms to competition between supply chains. A customer's sharing activities with its supplier may contribute to an increase in innovation performance. The supplier's information-sharing activity with its customer could affect its information-sharing activities with its main supplier. Cooperative activity with a partner in the supply chain is cultivated and amassed into relationship knowledge, and this study shows that the cooperative relational knowledge related to information-sharing activities enables firms to participate in sharing activities with their main suppliers. Increasing evidence shows that sharing various activities between buyer and supplier improves trust and performance outcomes, and enables firms to maintain competitive advantage. From the perspective of knowledge theory, external knowledge is becoming more important in firms' innovation activities, because innovative knowledge is acquired primarily through interaction with another organization. In addition, relationship learning could be an important tool in absorbing the supplier's core technology, information, expertise, and core competencies, increasing relational value.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.05a
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• pp.347-350
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• 2018

In order for an IoT system to automatically make the house temperature pleasant for the user, the system needs to predict the optimal start-up time of air-conditioner or heater to get to the temperature that the user has set. Predicting the optimal start-up time is important because it prevents extra fee from the unnecessary operation of the air-conditioner and heater. This paper introduces an ANN(Artificial Neural Network) and an IoT system that predicts the cooling and heating time in households using air-conditioner and heater. Many variables such as house structure, house size, and external weather condition affect the cooling and heating. Out of the many variables, measurable variables such as house temperature, house humidity, outdoor temperature, outdoor humidity, wind speed, wind direction, and wind chill was used to create training data for constructing the model. After constructing the ANN model, an IoT system that uses the model was developed. The IoT system comprises of a main system powered by Raspberry Pi 3 and a mobile application powered by Android. The mobile's GPS sensor and an developed feature used to predict user's return.