• Progress in Medical Physics
• /
• v.26 no.1
• /
• pp.52-58
• /
• 2015

The automated dental cavity detection program for a new concept intra-oral dental x-ray imaging device, an auxiliary diagnosis system, which is able to assist a dentist to identify dental caries in an early stage and to make an accurate diagnosis, was to be developed. The primary theory of the automatic dental cavity detection program is divided into two algorithms; one is an image segmentation skill to discriminate between a dental cavity and a normal tooth and the other is a computational method to analyze feature of an tooth image and take an advantage of it for detection of dental cavities. In the present study, it is, first, evaluated how accurately the DRLSE (Direct Regularized Level Set Evolution) method extracts demarcation surrounding the dental cavity. In order to evaluate the ability of the developed algorithm to automatically detect dental cavities, 7 tooth phantoms from incisor to molar were fabricated which contained a various form of cavities. Then, dental cavities in the tooth phantom images were analyzed with the developed algorithm. Except for two cavities whose contours were identified partially, the contours of 12 cavities were correctly discriminated by the automated dental caries detection program, which, consequently, proved the practical feasibility of the automatic dental lesion detection algorithm. However, an efficient and enhanced algorithm is required for its application to the actual dental diagnosis since shapes or conditions of the dental caries are different between individuals and complicated. In the future, the automatic dental cavity detection system will be improved adding pattern recognition or machine learning based algorithm which can deal with information of tooth status.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.3
• /
• pp.414-419
• /
• 2020

An artificial intelligence-based cable tension estimation model was developed to expand the utilization of data obtained from cable accelerometers of cable-stayed bridges. The model was based on an algorithm for selecting the natural frequency in the tension estimation process based on the vibration method and an applied artificial neural network (ANN). The training data of the ANN was composed after converting the cable acceleration data into the frequency, and machine learning was carried out using the characteristics with a pattern on the natural frequency. When developing the training data, the frequencies with various amplitudes can be used to represent the frequencies of multiple shapes to improve the selection performance for natural frequencies. The performance of the model was estimated by comparing it with the control criteria of the tension estimated by an expert. As a result of the verification using 139 frequencies obtained from the cable accelerometer as the input, the natural frequency was determined to be similar to the real criteria and the estimated tension of the cable by the natural frequency was 96.4% of the criteria.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.26 no.1
• /
• pp.56-63
• /
• 2016

In this study, we introduce a design of Fuzzy RBFNNs-based digit recognition system using the incremental-PCA in order to recognize the handwritten digits. The Principal Component Analysis (PCA) is a widely-adopted dimensional reduction algorithm, but it needs high computing overhead for feature extraction in case of using high dimensional images or a large amount of training data. To alleviate such problem, the incremental-PCA is proposed for the computationally efficient processing as well as the incremental learning of high dimensional data in the feature extraction stage. The architecture of Fuzzy Radial Basis Function Neural Networks (RBFNN) consists of three functional modules such as condition, conclusion, and inference part. In the condition part, the input space is partitioned with the use of fuzzy clustering realized by means of the Fuzzy C-Means (FCM) algorithm. Also, it is used instead of gaussian function to consider the characteristic of input data. In the conclusion part, connection weights are used as the extended diverse types in polynomial expression such as constant, linear, quadratic and modified quadratic. Experimental results conducted on the benchmarking MNIST handwritten digit database demonstrate the effectiveness and efficiency of the proposed digit recognition system when compared with other studies.

• Korean Journal of Ecology and Environment
• /
• v.33 no.3 s.91
• /
• pp.230-243
• /
• 2000

A large-scale community data were patterned by utilizing an unsupervised learning algorithm in artificial neural networks. Data for benthic macroinvertebrates in streams of South Korea reported in publications for 12 years from 1984 to 1995 were provided as inputs for training with the Kohonen network. Taxa included for the training were 5 phylum, 10 class, 26 order, 108 family and 571 species in 27 streams. Abundant groups were Diptera, Ephemeroptera, Trichoptera, Plecoptera, Coleoptera, Odonata, Oligochaeta, and Physidae. A wide spectrum of community compositions was observed: a few tolerant taxa were collected at polluted sites while a high species richness was observed at relatively clean sites. The trained mapping by the Kohonen network effectively showed patterns of communities from different river systems, followed by patterns of communities from different environmental disturbances. The training by the proposed artificial neural network could be an alternative for organizing community data in a large-scale ecological survey.

• Journal of Elementary Mathematics Education in Korea
• /
• v.14 no.3
• /
• pp.937-957
• /
• 2010

The purpose of this study is to discover the features of symbol sense. This study tries to sum up the meaning and elements of symbol sense and the measures to improve them through documents. Also based on this, it analyzes the learning conditions about symbol sense for 6th grade mathematically able students and suggests the method that activates symbol sense in the math of elementary schools. Considering various studies on symbol sense, symbol sense means the exact knowledge and essential understanding in a comprehensive way. Symbol sense is an intuition about symbols that grasps the meaning of symbols, understands the situation of question, and realizes the usefulness of symbols in resolving a process. Considering all other scholars' opinions, this study sums up 5 elements of the symbol sense. (The recognition of needs to introduce symbol, ability to read the meaning of symbols, choice of suitable symbols according to the context, pattern guess through visualization, recognize the role of symbols in other context) This study draws the following conclusions after applying the symbol questionnaires targeting 6th grade mathematically able students : First, although they are math talents, there are some differences in terms of the symbol sense level. Second, 5 elements of the symbol sense are not completely separated. They are rather closely related in terms of mainly the symbol understanding, thereby several elements are combined.

• Education of Primary School Mathematics
• /
• v.20 no.1
• /
• pp.37-52
• /
• 2017

The purpose of this thesis is to analyze the current status of a program for an elementary math class for gifted students in Daegu and to propose a remedy. The main results of this thesis are as follows. First, goals of the gifted class and the basic operation direction were satisfactory, however plans for parent training programs and self evaluation of the classes were not presented. Therefore, it needs when and how to do for specific plan of gifted class evaluation and parent training programs. Second, The annual instruction plan has been restricted to the subject matter education and field trips and has not included specific teaching methods in accordance with the contents of learning program. The management of gifted classes, therefore, requires not only the subject matter education and field trips but also output presentations, leadership programs, voluntary activities, events and camps which promote the integral development of gifted students. Third, there is no duplication of content to another grade, and various activities did not cover the whole scope of math topics(eg. number and operation, geometry, measurement, pattern) equally. In accordance with elementary mathematics characteristics, teachers should equally distribute time in whole range of mathematics while they teach students in the class because it is critical to discover gifted students throughout the whole curriculum of elementary mathematics. Fourth, as there are insufficient support and operational lack of material development, several types of programs are not utilized and balanced. It is necessary for teachers to try to find the type of teaching methods in accordance with the circumstances and content, so that students can experience several types of programs. If through this study, we can improve the development, management and quality of gifted math programs, it would further the development of gifted education.

• Journal of The Korean Association For Science Education
• /
• v.30 no.6
• /
• pp.799-814
• /
• 2010

This study aimed at developing a set of question cards for fostering deep understanding and encouraging reasoning about fossils and analyze the characteristics of visitors' communication depending on whether to use the question cards in a fossil gallery. Through several steps, a card set consisted of nine generic questions about fossil exhibitions and guidance for using question cards were developed. Data related to visitors' communications were collected from 18 peer groups (from 5th to 9th grade) visiting the fossil gallery of Gwacheon National Science Museum. Visiting groups' interactions were videotape recorded and transcribed. 'Holding time,' the types of 'actions,' and the types of 'conversation' were analysed. Visitors' actions were divided into three categories: ‘look’, 'speech', and 'motion.' Furthermore, visitors' conversations categorized as 'speech' were subdivided into four patterns: 'enumerative,' 'consensual,' 'responsive,' and 'argumentative.' Using the question cards contributes to increase holding time and most of the visiting actions. Most of the conversation patterns also increased except the responsive pattern. In conclusion, using question cards in a fossil gallery could facilitate concentrated and meaningful visits by enhancing active verbal and non-verbal communications between exhibit and visitor or among visitors, encouraging visitors' reasoning about exhibits, and guiding visitors what and how to focus on exhibits.

• Journal of Science Education
• /
• v.44 no.2
• /
• pp.167-182
• /
• 2020

The active participation and active interaction of learners in small group science inquiry activities are the main factors that determine the effectiveness of science learning. Roles can be assigned to members of a small group to facilitate interaction between members within the small group. The purpose of this study is to analyze the effect of role assignment on the types and patterns of verbal interactions in middle school students' small group science inquiry activities. For this, 172 students from middle schools located in metropolitan cities were surveyed. We analyzed 18 small groups with assigned roles and 15 small groups without assigned roles. The change in verbal interaction type in small group science inquiry activity according to role assignment was largely divided into alienation and participation. In the case of small groups with assigned roles, the participation type occupied a higher proportion than the alienation type. The change in verbal interaction patterns did not show much significant differences when the role was assigned in terms of cognitive and affective. Based on this, further research is needed on how role assignment affects verbal interactions depending on the type of scientific inquiry and the stage of inquiry. In addition, further research on the composition of small groups and role assignment is required.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.22 no.3
• /
• pp.471-479
• /
• 2018

Recently, the spread of smart TV based Android iOS Set Top box has become common. This paper propose a new approach to control the TV using gestures away from the era of controlling the TV using remote control. In this paper, the AdaBoost algorithm is applied to gesture recognition by using a mono camera. First, we use Camshift-based Body tracking and estimation algorithm based on Gaussian background removal for body coordinate extraction. Using global and local feature vectors, we recognized gestures with speed change. By tracking the time interval trajectories of hand and wrist, the AdaBoost algorithm with CART algorithm is used to train and classify gestures. The principal component feature vector with high classification success rate is searched using CART algorithm. As a result, 24 optimal feature vectors were found, which showed lower error rate (3.73%) and higher accuracy rate (95.17%) than the existing algorithm.

• Journal of Technology Innovation
• /
• v.17 no.2
• /
• pp.25-53
• /
• 2009

The purpose of this paper is to analysis sectoral patterns of technological innovation in Korean manufacturing sector. Pavitt(1984) put forward a well-known taxonomy that industries three groups of industries characterized by markedly different innovative modes, namely science-based, production-intensive and supplier-dominated industries. Using Pavitt's taxonomy as a framework, we try to explain similarities and differences among sectors in the sources and impact of innovations. Based on a sample of 2,371 firms in manufacturing industry, this paper investigated its relevance to explain the sources and directions of innovative activities in Korean industries. Empirical study shows that in supplier dominated firms most process innovations come from suppliers of equipment and materials. In science-based firms product innovation is produced internally, based on the rapid development of the underlying sciences in the universities and research institutes. It also shows that production-intensive firms have a positive association between innovativeness and customer collaboration. This explanation has implications for our understanding of the sources and directions of technical changes, the formation of technological advantages at the level of both region and country.