• Journal of the Computational Structural Engineering Institute of Korea
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• v.37 no.4
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• pp.225-232
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• 2024

This study focuses on the determination of the fracture mode in composite laminates using deep learning. With the increase in the use of laminated composites in numerous engineering applications, the insurance of their integrity and performance is of paramount importance. However, owing to the complex nature of these materials, the identification of fracture modes is often a tedious and time-consuming task that requires critical domain knowledge. Therefore, to alleviate these issues, this study aims to utilize modern artificial intelligence technology to automate the fractographic analysis of laminated composites. To accomplish this goal, scanning electron microscopy (SEM) images of fractured tensile test specimens are obtained from laminated composites to showcase various fracture modes. These SEM images are then categorized based on numerous fracture modes, including fiber breakage, fiber pull-out, mix-mode fracture, matrix brittle fracture, and matrix ductile fracture. Next, the collective data for all classes are divided into train, test, and validation datasets. Two state-of-the-art, deep learning-based pre-trained models, namely, DenseNet and GoogleNet, are trained to learn the discriminative features for each fracture mode. The DenseNet models shows training and testing accuracies of 94.01% and 75.49%, respectively, whereas those of the GoogleNet model are 84.55% and 54.48%, respectively. The trained deep learning models are then validated on unseen validation datasets. This validation demonstrates that the DenseNet model, owing to its deeper architecture, can extract high-quality features, resulting in 84.44% validation accuracy. This value is 36.84% higher than that of the GoogleNet model. Hence, these results affirm that the DenseNet model is effective in performing fractographic analyses of laminated composites by predicting fracture modes with high precision.

• Journal of Digital Convergence
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• v.10 no.8
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• pp.73-80
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• 2012

Consulting industry is a knowledge intensive business service industry to lead to knowledge creation as well as support high value creation of other industries. While the consulting industry has a great ripple effect on whole industries, there is a lack of interest in the consulting industry. Thus, this study investigates a ripple effect of the consulting service on the national economy using an Input-Output analysis. We summarize some of our findings as follows. First, A production of 1.0 won in the business consulting industry induces production of 0.6933 won in 2005 and 0.7851 in 2009; value-added of 0.2881 won in 2005 and 0.3039 won in 2009. A production of 1.0 billion won in the business consulting industry Industry produces employment for 0.1124 persons in 2005 and 0.1207 persons in 2009. Second, the supply shortage of 1.0 won in the business consulting industry prevents other industries from producing 2.6759 won in 2005 and 3.0145 won in 2009. Third, a 10% increase in the price level of the business consulting industry raises the overall price level from 0.1691% in 2005 to 0.2161% in 2009. The research results show that consulting industry has been increasing a effect on Korea national economy.

• Journal of the Korean Electrochemical Society
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• v.24 no.2
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• pp.28-33
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• 2021

Many researchers have increased the loading level of electrodes to improve the energy density of secondary batteries. In this study, high-loading NCM523 (LiNi_0.5Co_0.2Mn_0.3O₂) positive electrode is manufactured using a polytetrafluoroethylene (PTFE) binder, not the conventional polyvinylidene fluoride (PVdF) binder, which has been commonly used in lithium-ion batteries. Through the kneading process using PTFE suspension, not the conventional slurry process using PVdF solution in N-methyl-2-pyrrolidinone (NMP), thick electrodes with high loading are easily manufactured. When the PTFE and PVdF-based electrodes are prepared at a loading level of 5.0 mAh/cm², respectively, the PTFE-based electrode shows better cycle performance and rate capability than those of PVdF-based electrodes. The electrode manufactured by the kneading process using a PTFE binder has high electrode porosity due to insufficient roll-press, but the porosity can be lowered by high temperature roll-press over 120℃. However, there is no significant difference in cycle performance according to the roll press temperature. In addition, the cycle performance of the high loading electrode is slightly improved by increasing the content of the conductive material. Overall, the PTFE binder can improve the performance of the high loading electrode, but additional solutions will be needed.

• Journal of Digital Convergence
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• v.11 no.12
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• pp.275-285
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• 2013

As the world economy has been changed into the knowledge-based society, all economic activities have globalized and intensified competition in the marketplace, and the forces of these changes are even more aggressively pressuring today's business. According to many businesses are focused on the core competence and various functions are outsourced by service providers, many firms pay heavily attention to business service. Although the importance of business service, domestic business service industry shows a low labor productivity. On the other hand, foreign business service companies in korea take a substantial portion of business service market. Thus, domestic business service needs to increase a competitiveness because of potential growth opportunities. This study attempts to find out the ripple effect of business service industry on other industry.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.185.2-185.2
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• 2010

한반도 국가바람지도(김현구, 2009)는 한국에너지기술연구원에서 지식경제부의 부처임무사업으로 구축되었으며 현재 웹서비스(http://www.kier-wind.org)를 통하여 정보를 제공하고 있다. 국가바람지도는 수치기상예측(NWP; Numerical Weather Prediction) 모델을 이용하여 영토, 영해에 대해 $1km{\times}1km$의 고해상도로 작성한 뒤(이순환 등, 2009) 풍력자원 정보로 재가공되었다. 한반도 국가바람지도는 5년의 장기간에 대한 시계열 수치기상예측에 의하여 구축되었기 때문에 데이터베이스(DB; database)의 효율적 관리가 필연적으로 요구된다. MM5 또는 WRF 모델의 고유 출력포맷의 자료구조는 풍력자원분석에 필요한 기상요소 외에도 대기과학자에게 필요한 수많은 기상인자를 종합적으로 포함하고 있다. 따라서 2차원 층(layer) 또는 3차원 공간분포 분석 및 계산격자인 셀(cell)에서의 1차원 시계열 분석 등 다양한 자료축출에는 비효율적인 자료구조가 된다. 이러한 자료구조의 불편을 해소하기 위해서는 기상요소별로 독립적이고 빈번한 시계열 자료 추출에 효율성을 가지며 어떤 프로그래밍 언어를 사용하든지 직관적으로 쉽게 사용할 수 있는 바람지도 데이터베이스의 재구성이 요구된다. 이에 대용량 수치자료의 처리 측면에서 장점을 가지는 과학기술 프로그래밍 언어인 IDL을 기반으로 국가바람지도의 자료구조를 효율화하여 데이터베이스화 하였으며 IDL에 내재된 그래픽 기능을 활용하여 가시화를 구현함으로써 연구개발자의 입장에서 국가바람지도의 활용성 및 효율성을 향상시키고자 하였다.

• Journal of Korean Library and Information Science Society
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• v.42 no.1
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• pp.417-440
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• 2011

Public libraries face various changes and challenges in the knowledge society of the 21st century. The necessity of introducing 'marketing' concept into the management of public libraries is increasing. This study focuses on 'Family Place Library' program among the children services of public libraries in the United States. 'Family Place Library' is the library program for the youngest children and families, which has been spread over 300 public libraries of USA until February, 2011. The researcher did participation observation and in-depth interview at the libraries which are the main cases for 'Family Place Libraries' in New York, USA. And the researcher analysed the content of the program and did in-depth interviews with related professionals in and out of libraries over many states of USA. Based on the results of this study, the researcher suggested marketing strategies for the management of public libraries.

• Journal of Korean Library and Information Science Society
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• v.45 no.3
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• pp.119-139
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• 2014

The objective of this study is to establish and propose a construction plan for a new main library in a metropolitan city. The case to be discussed in this paper is the new library of Busan. Library Law revised in 2007 requires each metropolitan cities and provinces to designate a public library as the representative regional main library or to build a new one. The city of Busan has been enthusiastic to build a new main library that can serve as a representative public library for the citizen. This new public library will serve as a community center, an intellectual archive, and the policy hub for the regional information services. In this paper, the strategy for the new Busan central metropolitan library will be discussed. It will strive to illustrate elements to be considered for the planning of a regional central library as other citied and provinces may refer to for their own regional central libraries.

• KIPS Transactions on Software and Data Engineering
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• v.3 no.12
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• pp.523-530
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• 2014

Ontology alignment is the way to share and reuse of ontology knowledge. Because of the ambiguity of concept, most ontology alignment systems combine a set of various measures and complete enumeration to provide the satisfactory result. However, calculating process becomes more complex and required time increases exponentially since the number of concept increases, more errors can appear at the same time. Lately the focus is on meta-matching using the heuristic algorithm. Existing meta-matching system tune extra parameter and it causes complex calculating, as a consequence, the results in the various data of specific domain are not good performed. In this paper, we propose a high performance algorithm by using DCS that can solve ontology alignment through simple process. It provides an efficient search strategy according to distribution of Levy Flight. In order to evaluate the approach, benchmark data from the OAEI 2012 is employed. Through the comparison of the quality of the alignments which uses DCS with state of the art ontology matching systems.

• Journal of Intelligence and Information Systems
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• v.10 no.2
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• pp.111-131
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• 2004

Software change is an essential operation for software evolution. To maintain the system competently, managers as well as developers must be able to understand the structure of the system but the structure of software is hidden to the developers and managers who need to change it. In this paper, we present a system (OntCIA) for supporting change impact analysis for rating and billing domain based on the semantic web technology. The basic idea of OntCIA is to build a domain knowledge base using an OWL ontology and RDF to implement change impact analysis system that would support the managers and software developers in finding out information about structure of large software system. OntCIA allows users to incrementally build an ontology in rating and billing domain and provides useful information in response to user queries concerning the code, such as, for example 'Find the modules which have a role for confirming new subscription'. The strengths of OntCIA are its architecture for easy maintenance as well as semantic indexing by automatic reasoning.

• Journal of Korean Library and Information Science Society
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• v.48 no.4
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• pp.1-20
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• 2017

The most important identity of public library is local public goods that guarantee access and use of knowledge and information of local residents. To justify this, the library must create an optimal lighting environment. Particularly, since the perception rate of information through vision is over 80%, it is necessary to secure proper illuminance. This study measured the illuminance level of public libraries in Daegu. Based on the results, this study suggested a desirable illuminance level for each space and proposed plans to secure and maintain proper illuminance(prospective revision of the KS A 3011, setting the illuminance range for each space of the local government, replacing the existing lighting fixtures with LED, enhance supervision of lighting management, establishment of basic principles for proper lighting and detailed plans for each space of the library, investigation and reflection on users' complaints and satisfaction, etc.)