• Journal of the Korea Society of Computer and Information
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• v.25 no.10
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• pp.35-42
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• 2020

In this study, we propose a crack detection method using limited data with a U-Net based image inpainting technique that is a modified unsupervised anomaly detection method. Concrete cracking occurs due to a variety of causes and is a factor that can cause serious damage to the structure in the long term. In general, crack investigation uses an inspector's visual inspection on the concrete surfaces, which is less objective in judgment and has a high possibility of human error. Therefore, a method with objective and accurate image analysis processing is required. In recent years, the methods using deep learning have been studied to detect cracks quickly and accurately. However, when the amount of crack data on the building or infrastructure to be inspected is small, existing crack detection models using it often show a limited performance. Therefore, in this study, an unsupervised anomaly detection method was used to augment the data on the object to be inspected, and as a result of learning using the data, we confirmed the performance of 98.78% of accuracy and 82.67% of harmonic average (F1_Score).

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.6
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• pp.699-706
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• 2015

This paper presents results of one-year monitoring on prestressing force of a 7-wire steel post-tensioning strand which is installed in a UHPC(ultra high performance concrete) bridge with 11.0 m long, 5.0 m wide, and 0.6 m high by using a FBG-encapsulated 7-wire steel strand. The initial prestressing forces and the prestress changes during a vehicle load test were measured using the FBG-encapsulated strand. The results show that the FBG-encapsulated 7-wire strand is very effective for monitoring the prestress forces even the change in the tension force is very small. Additionally, it was indicated that selection of the thermal expansion coefficient which is used for the temperature correction shall be carefully carried out.

• Journal of Digital Contents Society
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• v.19 no.4
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• pp.837-844
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• 2018

Recently, the cloud technology has made dynamical network changes by enabling the construction of a logical network without building a physical network. Despite recent research on the cloud, it is necessary to study security functions for the identification of fake virtual network functions and the encryption of communication between entities. Because the VNFs are open to subscribers and able to implement service directly, which can make them an attack target. In this paper, we propose a virtual public key infrastructure mechanism that detects a fake VNFs and guarantees data security through mutual authentication between VNFs. To evaluate the virtual PKI, we built a management and orchestration environment to test the performance of authentication and key generation for data security. And we test the detection of a distributed denial of service by using several AI algorithms to enhance the security in NFV.

• Journal of Digital Convergence
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• v.12 no.1
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• pp.89-97
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• 2014

As Big Data's value is perceived and Government 3.0 is announced, there is a growing interest in Big Data. However, it won't be easy for each public institute or local government to apply Big Data systematically and make a successful achievement despite lacking of specific alternative plan or strategy. So, this study tried to suggest strategies to use Big Data after arranging the area which local government utilize it in. As a result, utilization areas of local administration's Big Data are divided into four areas; recognizing and corresponding the abnormal phenomenon, predicting and corresponding the close future, corresponding analyzed situation and developing new policy(administration service), and citizen customized service. In addition, strategies about how to use Big Data are suggested; stepwise approach, user's requirements analysis, critical success factors based implementation, pilot project, result evaluation, performance based incentive, building common infrastructure.

• Journal of Digital Convergence
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• v.11 no.5
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• pp.73-81
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• 2013

The paradigm of IT ecosystem has been rapidly changing into open ecosystem irrespective of the territory on which the device, software and contents are located. IT venture ecosystem which can compete and collaborate with the global companies is really needed because the global opportunity of IT venture company has been expanding. Research model based on PEST-SWOT-AHP(Analytic Hierarchy Process) model was employed to analyze the current status and problems of IT venture ecosystem in Korea. Survey was conducted with 20 experts who are involved in venture companies, university, R&D research institute, and investment companies as a working group supported by the Ministry of Knowledge Economy (MKE). The empirical result showed that global promotion of IT ventures, coexistence and development of large enterprises and ventures, revitalization of investment infrastructure, and building of smart venture ecosystem are derived to revitalize IT venture ecosystem and suggested global revitalization model for smart IT venture ecosystem.

• Journal of Digital Convergence
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• v.12 no.1
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• pp.347-358
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• 2014

A smart TV is able to show terrestrial broadcasting and also can be used as a computer -VOD, games, image communications, application utilities and so on. In order to carry out Smart TV business, it has to contains contents, platforms, network terminal unit. If ill-equipped with any of these aboves, it must cooperate with other licensee. Therefore, Smart TV business is necessary to cooperate with each business agent. In this paper, we will look into domestic/foreign country Smart TV market, policy, vitalization strategy, and suggest the application of big data analysis methodology for Smart TV vitalization method - 1) hardware infrastructure building based on cloud computing 2) Network upgradability acceptable traffic increase 3) Technical development cooperation between each licensee 4) Variable Smart TV contents supply 5) Cooperation with party interested individuals in using UX/UI for N-Screen, network traffic estimation may increase, customized supply smart contents for consumer in real time.

• International Journal of Highway Engineering
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• v.18 no.6
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• pp.51-59
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• 2016

OBJECTIVES : The objective of this study is to estimate the appropriate storage required for deicing materials in Gangwon-do for successful snow removal operations during the 2018 Pyeongchang Winter Olympic Games. The final estimates of the deicing chemicals can be used by public agencies to aid decision making. METHODS : First, the database that exists in the road snow-removal management system (RSMS) of the Ministry of Land, Infrastructure, and Transport, South Korea was used to determine historical characteristics of snow removal experiences in Gangwon-do. The database includes historical information, including regional and road weather data and number of snow-removal works. Second, both the maximum and the actual amount of storages used for deicing materials in the past three years were analyzed. Lastly, the final estimates of the deicing materials were evaluated using an additional equation. It considers frequency of salt spray application, total administrative road length estimated by road agencies, and number of days required for snow removal works in Gangwon-do. Consequently, the results show that significant differences were not observed between the final estimates and the maximum amount used during the past three years. RESULTS : The final estimates of the deicing materials are almost similar to the maximum amount used during the past three years in Gangwon-do. CONCLUSIONS : The study shows that the estimates of deicing chemicals can be useful when decision making is required for the snow-removal policy.

• Journal of KIISE
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• v.44 no.9
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• pp.976-985
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• 2017

Wireless mesh network (WMN) is a promising technology for building a cost-effective and easily-deployed wireless networking infrastructure. To efficiently utilize limited radio resources in WMNs, packet transmissions (particularly, redundant packet transmissions) should be carefully managed. We therefore propose a lightweight traffic redundancy elimination (LTRE) scheme to reduce redundant packet transmissions in software-defined wireless mesh networks (SD-WMNs). In LTRE, the controller determines the optimal path of each packet to maximize the amount of traffic reduction. In addition, LTRE employs three novel techniques: 1) machine learning (ML)-based information request, 2) ID-based source routing, and 3) popularity-aware cache update. Simulation results show that LTRE can significantly reduce the traffic overhead by 18.34% to 48.89%.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.27 no.3
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• pp.273-294
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• 2016

This research is part of the Korean-ASEAN Official Development Assistance (ODA) project, specifically exploring the possibility of using public libraries as a place for Information and Communication Technology (ICT) literacy training for women from ASEAN (Association of Southeast Asian Nations) countries. Women from ASEAN countries are often minorities in ICT capacity building. A survey of 1,000 female public library users - 100 people from each of the ten ASEAN countries - and in-depth interviews with librarians from national libraries were conducted. The survey results showed that 68.8% of respondents perceived public libraries as a suitable place for ICT literacy training. 27.5% of respondents visited libraries for ICT-related activities, including information retrieval, e-mail, SNS, etc., Meanwhile, findings from the interviews highlighted the importance of having up-to-date ICT infrastructure - computers, Internet, professional ICT skill training for librarians, strategic planning for policies, budgets, and cooperation with other related institutions - in public libraries in order to provide effective ICT training.

• Journal of Internet Computing and Services
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• v.17 no.5
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• pp.17-23
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• 2016

Wireless sensor-actuator networks (WSANs) enhance the existing wireless sensor networks (WSNs) by equipping sensor nodes with an actuator. The actuators work with the sensor nodes and perform application-specific operations. The WSAN systems have several applications such as disaster relief, intelligent building, military surveillance, health monitoring, and infrastructure security. These applications require capability of reliable data transfer to act responsively and accurately. Biologically inspired modeling techniques have received considerable attention for achieving robustness, scalability, and adaptability, while retaining individual simplicity. In this paper, an epidemic-inspired algorithm for data dissemination with delay constraints while minimizing energy consumption in WSAN is proposed. The steady states and system stability are analyzed using control theory. Also, simulation results indicate that the proposed scheme provides desirable dissemination delay and energy saving.