• Title/Summary/Keyword: 한국컴퓨터

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Visual Classification of Wood Knots Using k-Nearest Neighbor and Convolutional Neural Network (k-Nearest Neighbor와 Convolutional Neural Network에 의한 제재목 표면 옹이 종류의 화상 분류)

  • Kim, Hyunbin;Kim, Mingyu;Park, Yonggun;Yang, Sang-Yun;Chung, Hyunwoo;Kwon, Ohkyung;Yeo, Hwanmyeong
    • Journal of the Korean Wood Science and Technology
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    • v.47 no.2
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    • pp.229-238
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    • 2019
  • Various wood defects occur during tree growing or wood processing. Thus, to use wood practically, it is necessary to objectively assess their quality based on the usage requirement by accurately classifying their defects. However, manual visual grading and species classification may result in differences due to subjective decisions; therefore, computer-vision-based image analysis is required for the objective evaluation of wood quality and the speeding up of wood production. In this study, the SIFT+k-NN and CNN models were used to implement a model that automatically classifies knots and analyze its accuracy. Toward this end, a total of 1,172 knot images in various shapes from five domestic conifers were used for learning and validation. For the SIFT+k-NN model, SIFT technology was used to extract properties from the knot images and k-NN was used for the classification, resulting in the classification with an accuracy of up to 60.53% when k-index was 17. The CNN model comprised 8 convolution layers and 3 hidden layers, and its maximum accuracy was 88.09% after 1205 epoch, which was higher than that of the SIFT+k-NN model. Moreover, if there is a large difference in the number of images by knot types, the SIFT+k-NN tended to show a learning biased toward the knot type with a higher number of images, whereas the CNN model did not show a drastic bias regardless of the difference in the number of images. Therefore, the CNN model showed better performance in knot classification. It is determined that the wood knot classification by the CNN model will show a sufficient accuracy in its practical applicability.

Layered Double Hydroxide Nanoparticles for Bio-Imaging Applications (LDH 나노입자 기반의 바이오 이미징 소재)

  • Jin, Wenji;Ha, Seongjin;Lee, Dongki;Park, Dae-Hwan
    • Korean Chemical Engineering Research
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    • v.57 no.4
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    • pp.445-454
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    • 2019
  • Layered double hydroxides (LDHs) nanoparticles have emerged as novel nanomaterials for bio-imaging applications due to its unique layered structure, physicochemical properties, and good biocompatibility. Bio-imaging is one of the most important fields for medical applications in clinical diagnostics and therapeutics of various diseases. Enhanced diagnostic techniques are needed to realize new paradigm for next-generation personalized medicine through nanoscale materials. When nanotechnology is introduced into bio-imaging system, nanoparticle probes can endow imaging techniques with enhanced ability to obtain information about biological system at the molecular level. In this review, we summarize structural features of LDH nanoparticles with current issues of bio-imaging system. LDH nanoparticle probes are also discussed through in vitro as well as in vivo studies in various bio-imaging techniques including fluorescence imaging, magnetic resonance imaging (MRI), positron emission tomography (PET), and computed X-ray tomography (CT), which will have the potential in the development of the advanced nanoparticles with high sensitivity and selectivity.

Connectivity Assessment Based on Circuit Theory for Suggestion of Ecological Corridor (생태축 제안을 위한 회로 이론 기초 연결성 평가)

  • Yoon, Eun-Joo;Kim, Eun-Young;Kim, Ji-Yeon;Lee, Dong Kun
    • Journal of Environmental Impact Assessment
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    • v.28 no.3
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    • pp.275-286
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    • 2019
  • In order to prevent local extinction of organisms and to preserve biodiversity, it is important to ensure connectivity between habitats. Even if the habitat is exposed to various disturbance factors, it is possible to avoid or respond to disturbances if they are linked to other habitats. Habitat connectivity can be assessed from a variety of perspectives, but the importance of functional connectivity based on species movement has been emphasized in recent years due to the development of computational capabilities and related software. Among them, Circuitscape, which is a connectivity evaluation tool, has an advantage it can provide detailed reference data for the city planning because it maps ecological flows on individual grid based on circuit theory. Therefore, in this study, the functional connectivity of Suwon was evaluated by applying Circuitscape and then, the ecological corridor to be conserved and supplemented was suggested based on it. The results of this study are expected to effectively complement the methodology related ecological corridor/axis, which was previously provided only in the form of a diagram, and to be effective in management of development project and urban planning.

Contents Analysis of Basic Software Education of Non-majors Students for Problem Solving Ability Improvement - Focus on SW-oriented University in Korea - (문제해결력 향상을 위한 비전공자 소프트웨어 기초교육 내용 분석 - 국내 SW중심대학 중심으로 -)

  • Jang, Eunsill;Kim, Jaehyoun
    • Journal of Internet Computing and Services
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    • v.20 no.4
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    • pp.81-90
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    • 2019
  • Since 2015, the government has been striving to strengthen the software capabilities required for future talent through software-oriented university in Korea. In the university selected as a software-oriented university, basic software education is given to all departments such as humanities, social science, engineering, natural science, arts and the sports within the university in order to foster convergent human resources with different knowledge and software literacy. In this paper, we analyze the contents of basic software education for twenty universities selected as software-oriented universities. As a result of analysis, most of the basic software education which is carried out to the students of the non-majors students was aimed at improvement of problem solving ability centered on computational thinking for future society and improvement of convergence ability based on computer science. It uses block-based educational programming language and text-based advanced programming language to adjust the difficulty of programming contents and contents reflecting characteristics of each major. Problem-based learning, project-based learning, and discussion method were used as the teaching and learning methods for problem solving. In the future, this paper will help to establish the systematic direction for basic software education of non-majors students.

Variable Selection of Feature Pattern using SVM-based Criterion with Q-Learning in Reinforcement Learning (SVM-기반 제약 조건과 강화학습의 Q-learning을 이용한 변별력이 확실한 특징 패턴 선택)

  • Kim, Chayoung
    • Journal of Internet Computing and Services
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    • v.20 no.4
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    • pp.21-27
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    • 2019
  • Selection of feature pattern gathered from the observation of the RNA sequencing data (RNA-seq) are not all equally informative for identification of differential expressions: some of them may be noisy, correlated or irrelevant because of redundancy in Big-Data sets. Variable selection of feature pattern aims at differential expressed gene set that is significantly relevant for a special task. This issues are complex and important in many domains, for example. In terms of a computational research field of machine learning, selection of feature pattern has been studied such as Random Forest, K-Nearest and Support Vector Machine (SVM). One of most the well-known machine learning algorithms is SVM, which is classical as well as original. The one of a member of SVM-criterion is Support Vector Machine-Recursive Feature Elimination (SVM-RFE), which have been utilized in our research work. We propose a novel algorithm of the SVM-RFE with Q-learning in reinforcement learning for better variable selection of feature pattern. By comparing our proposed algorithm with the well-known SVM-RFE combining Welch' T in published data, our result can show that the criterion from weight vector of SVM-RFE enhanced by Q-learning has been improved by an off-policy by a more exploratory scheme of Q-learning.

Predictors of Intention to Work among People with Disabilities who Maintain Economic Inactivity (비경제활동 유지 장애인의 취업의사 예측변인 탐색)

  • An, Yeji;Ji, Eun
    • 재활복지
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    • v.21 no.3
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    • pp.65-84
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    • 2017
  • This study identified predictors of intention to work among people with disabilities who maintain economic inactivity for two successive years by analyzing a total of 2,255 Participants in the 2014 data of the Panel Survey of Employment for the Disabled (PSED) with through $X^2$, t test, logistic regression. To explore factors affecting intention to work among people with disabilities who maintain economic inactivity, this study hypothesized the effectiveness of variables of demographic, disability, human resources, psycho-social factors based on previous studies. The analysis showed that male, spouse-being, low income status out of demographic variables were related to high probability of having intention to work among people with disabilities who maintain economic inactivity. In case of disability variables, experiencing disability-related discrimination significantly predicted the probability of having intention to work. However, the relationship between disability-related discrimination experiences and high intention to work needs to be viewed as correlated rather than cause-and-effect.In addition, literacy related to computer use/English proficiency/interpersonal and adaptation skills(human resources), experiences of vocational rehabilitation services (human resources), self-esteem (psycho-social) significantly predicted the probability of having intention to work among people with disabilities who maintained economic inactivity. Based on these results, support services for females with disabilities, effective rehabilitation programs of improving literacy related to computer use/English proficiency/interpersonal and adaptation skills and self-esteem, general expansion of vocational rehabilitation services for people with disabilities are suggested.

Estimation Method of Predicted Time Series Data Based on Absolute Maximum Value (최대 절대값 기반 시계열 데이터 예측 모델 평가 기법)

  • Shin, Ki-Hoon;Kim, Chul;Nam, Sang-Hun;Park, Sung-Jae;Yoo, Sung-Soo
    • Journal of Energy Engineering
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    • v.27 no.4
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    • pp.103-110
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    • 2018
  • In this paper, we introduce evaluation method of time series prediction model with new approach of Mean Absolute Percentage Error(hereafter MAPE) and Symmetric Mean Absolute Percentage Error(hereafter sMAPE). There are some problems using MAPE and sMAPE. First MAPE can't evaluate Zero observation of dataset. Moreover, when the observed value is very close to zero it evaluate heavier than other methods. Finally it evaluate different measure even same error between observations and predicted values. And sMAPE does different evaluations are made depending on whether the same error value is over-predicted or under-predicted. And it has different measurement according to the each sign, even if error is the same distance. These problems were solved by Maximum Mean Absolute Percentage Error(hereafter mMAPE). we used the absolute maximum of observed value as denominator instead of the observed value in MAPE, when the value is less than 1, removed denominator then solved the problem that the zero value is not defined. and were able to prevent heavier measurement problem. Also, if the absolute maximum of observed value is greater than 1, the evaluation values of mMAPE were compared with those of the other evaluations. With Beijing PM2.5 temperature data and our simulation data, we compared the evaluation values of mMAPE with other evaluations. And we proved that mMAPE can solve the problems that we mentioned.

Non-Disruptive Server Management for Sustainable Resource Service Based on On-Premise (온-프레미스 기반 지속적인 자원 서비스를 위한 서버 무중단 기법)

  • Kim, Hyun-Woo
    • KIPS Transactions on Computer and Communication Systems
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    • v.7 no.12
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    • pp.295-300
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    • 2018
  • The rapid development of IT, many conventional passive jobs have been automated. This automation increases the leisure time of many people and various services are being developed for them. In addition, with the advent of smart devices that are compact and portable, it is possible to use various internet services without any time and place discretion. Various studies based on virtualization are under way to efficiently store and process large data generated by many devices and services. Desktop Storage Virtualization (DSV), which integrates and provides users with on-premise-based distributed desktop resources during these studies, uses virtualization to consolidate unused resources within distributed, legacy desktops. This DSV is very important for providing high reliability to users. In addition, research on hierarchical structure and resource integration for efficient data distribution storage processing in a distributed desktop-based resource integration environment is underway. However, there is a lack of research on efficient operation in case of server failure in on-premise resource integration environment. In this paper, we propose Non-disruptive Server Management (NSM) which can actively cope with the failure of desktop server in distributed desktop storage environment based on on-premise. NSM is easy to add and remove desktops in a desktop-based integrated environment. In addition, an alternative server is actively performed in response to a failure occurrence.

A Study on Improving Performance of the Deep Neural Network Model for Relational Reasoning (관계 추론 심층 신경망 모델의 성능개선 연구)

  • Lee, Hyun-Ok;Lim, Heui-Seok
    • KIPS Transactions on Software and Data Engineering
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    • v.7 no.12
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    • pp.485-496
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    • 2018
  • So far, the deep learning, a field of artificial intelligence, has achieved remarkable results in solving problems from unstructured data. However, it is difficult to comprehensively judge situations like humans, and did not reach the level of intelligence that deduced their relations and predicted the next situation. Recently, deep neural networks show that artificial intelligence can possess powerful relational reasoning that is core intellectual ability of human being. In this paper, to analyze and observe the performance of Relation Networks (RN) among the neural networks for relational reasoning, two types of RN-based deep neural network models were constructed and compared with the baseline model. One is a visual question answering RN model using Sort-of-CLEVR and the other is a text-based question answering RN model using bAbI task. In order to maximize the performance of the RN-based model, various performance improvement experiments such as hyper parameters tuning have been proposed and performed. The effectiveness of the proposed performance improvement methods has been verified by applying to the visual QA RN model and the text-based QA RN model, and the new domain model using the dialogue-based LL dataset. As a result of the various experiments, it is found that the initial learning rate is a key factor in determining the performance of the model in both types of RN models. We have observed that the optimal initial learning rate setting found by the proposed random search method can improve the performance of the model up to 99.8%.

Analysis of Teaching and Learning Process in Physical Computing Class for Elementary Gifted Students in Science (코딩블록을 활용한 초등 과학영재 대상 피지컬 컴퓨팅수업의 교수·학습 과정 분석)

  • Kim, Jiye;Jhun, Youngseok
    • Journal of The Korean Association of Information Education
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    • v.22 no.6
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    • pp.613-628
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    • 2018
  • The purpose of this study is to analyze the teaching and learning process of physical computing using coding block for elementary gifted students in science. In order to obtain implications for teaching physical computing, we set the learning objectives from the Computer and Information Literacy Evaluation Standards developed by the International Association for the Evaluation of Educational Achievement(IEA) and developed a teaching and learning program for physical computing through collaboration between science education and computer education experts according to learning objectives. The developed program was related to the use of the coding block MODI(TM) and 32 classes of physical computing instruction were conducted for 15 students of the 4th to 6th grade who belong to an education institute for the gifted in science affiliated to the University. In the physical computing class, the teaching and learning process was analyzed by collecting data such as classroom videos, class observation logs, teacher and student questionnaires, and interviews. Based on the results of the study, the implications of the teaching and learning process of physical computing using the coded blocks in the school education field were suggested. And we also explored the strategy of expanding the computational thinking through the activities of coding instruction to realize creative ideas.