• Advanced Composite Materials
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• v.17 no.3
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• pp.277-299
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• 2008

High quality and expedient processing repair methods are necessary to enhance the service life of bridge structures. Deterioration of concrete can occur as a result of structural cracks, corrosion of reinforcement, and freeze.thaw cycles. Cost effective methods with potential for field implementation are necessary to address the issue of the vulnerability of bridge structures and how to repair them. Most infrastructure related applications of fiber-reinforced plastics (FRPs) use traditional hand lay-up technology. The hand lay-up is tedious, labor-intensive and relies upon personnel skill level. An alternative to traditional hand lay-up of FRP for infrastructure applications is Vacuum Assisted Resin Transfer Molding (VARTM). VARTM uses single sided molding technology to infuse resin over fabrics wrapping large structures, such as bridge girders and columns. There is no work currently available in understanding the interface developed, when VARTM processing is adopted to wrap fibers such as carbon and/or glass over concrete structures. This paper investigates the interface formed by carbon fiber processed on to a concrete surface using the VARTM technique. Various surface treatments, including sandblasting, were performed to study the pull-off tensile test to find a potential prepared surface. A single-lap shear test was used to study the bond strength of CFRP fabric/epoxy composite adhered to concrete. Carbon fiber wraps incorporating Sikadur HEX 103C and low viscosity epoxy resin Sikadur 300 were considered in VARTM processing of concrete specimens.

• Journal of Korea Multimedia Society
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• v.14 no.5
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• pp.703-709
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• 2011

State-based infrastructure on IT-based network are prone to numerous cyber attack including subsequent hacking and internet infringement. These acts of terrorism are increasing because of the expanding IT convergence technology. Recently, the trend on cyber security monitoring and control researches focus on combining the general idea of security monitoring and control along with IT field and other control systems. This convergence trend has been increasing in both the use and importance. This research analyzes the state-based infrastructure monitoring and control system, its vulnerability as well as its improvement by incorporating the cyber convergence systems to existing systems. The subject of this research is for extensive use of CCTV systems which is expanded for 'CCTV Monitoring and Control Field' as well as 'Traffic Monitoring and Control Field' operated by 'Intelligent Traffic Information System' and Disaster Management Area which is studied in various fields. Eventually, the objective of the paper is to solve these issues, to apply related systems and to suggest improvement on the convergence system.

• Convergence Security Journal
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• v.20 no.4
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• pp.197-208
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• 2020

Based on the network infrastructure advanced in the information knowledge society, the structure of computer net work is operated by establishing the composition of network in various forms that have secured the security. In case of computer network of national/public organizations, it is necessary to establish the technical and managerial securit y environment even considering the characteristics of each organization and connected organizations. For this, the im portance of basic researches for cyber training by analyzing the technical/managerial vulnerability and cyber threats based on the classification and map of cyber threats according to the characteristics of each organization is rising. T hus, this study aims to analyze each type of external/internal cyber threats to computer network of national/public o rganizations established based on the dualistic infrastructure network of internet and national information network, a nd also to present the cyber threat framework for drawing the elements of cyber security training, by drawing and analyzing the actual elements of cyber threats through the case-based scenario.

• Advances in concrete construction
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• v.14 no.3
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• pp.153-167
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• 2022

The interaction between blast load and structures, as well as the interaction among structural members may well affect the structural response and damages. Therefore, it is necessary to analyse more realistic reinforced concrete structures in order to gain an extensive knowledge on the possible structural response under blast load effect. Among all the civilian structures, columns are considered to be the most vulnerable to terrorist threat and hence detailed investigation in the dynamic response of these structures is essential. Therefore, current research examines the effect of blast loads on the reinforced concrete columns via development of Pressure- Impulse (P-I) diagrams. In the finite element analysis, the level of damage on each of the aforementioned RC column will be assessed and the response of the RC columns when subjected to explosive loads will also be identified. Numerical models carried out using LS-DYNA were compared with experimental results. It was shown that the model yields a reliable prediction of damage on all RC columns. Validation study is conducted based on the experimental test to investigate the accuracy of finite element models to represent the behaviour of the models. The blast load application in the current research is determined based on the Lagrangian approach. To develop the designated P-I curves, damage assessment criteria are used based on the residual capacity of column. Intensive investigations are implemented to assess the effect of column dimension, concrete and steel properties and reinforcement ratio on the P-I diagram of RC columns. The produced P-I models can be applied by designers to predict the damage of new columns and to assess existing columns subjected to different blast load conditions.

• Journal of Positioning, Navigation, and Timing
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• v.2 no.2
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• pp.101-108
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• 2013

GPS is the most widely-used Positioning, Navigation, and Timing (PNT) system. Since GPS is an important PNT infrastructure, the vulnerability of GPS to signal jamming has received significant attention. Especially, South Korea has experienced intentional high-power jamming from North Korea for the past three years, and thus realized the necessity of a complementary PNT system. South Korea recently decided to deploy a high-power terrestrial navigation system, eLoran, as a complementary PNT system. According to the plan, the initial operational capability of the Korean eLoran system is expected by 2016, and the full operational capability is expected by 2018. As a necessary research tool to support the Korean eLoran program, an eLoran performance simulation tool for Korea is under development. In this paper, the received signal strength, which is necessary to simulate eLoran performance, from the suggested Korean eLoran transmitters is simulated with the consideration of effective ground conductivities over Korea. Then, eLoran signal-to-noise ratios are also simulated based on atmospheric noise data over Korea. This basic simulation tool will be expanded to estimate the navigation performance (e.g., accuracy, integrity, continuity, and availability) of the Korean eLoran system.

• Korean Journal of Oriental Medicine
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• v.16 no.3
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• pp.127-133
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• 2010

The purpose of this study is to develop the order communication system for Traditional Korean Medicine(TKM) which can support prescribing decisions and provide the toxicological information. The relative vulnerability of the infrastructure of TKM has made us start the study. We carried out the benchmarking for TKM charting solution firstly, and then designed the intelligent search and supporting method for prescription decisions. We developed of the medical herbs database and the web-based order communication program which can be used in medical field actually. This system supplies a various functions to oriental medical doctors such as management for prescription history, search for herb's effects, generating prescriptions, inventory management, alerting of toxicity and taboo, guideline for taking medicine, and so on. The design and implementation process has been described in this research. We expect that this system will play an important role in electronic medical record(EMR) or electronic health record(EHR) binding diagnosis and management functions.

• Journal of Internet Computing and Services
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• v.9 no.6
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• pp.73-79
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• 2008

Nowadays, all over the world's banks use internet banking through various authentication methods. Although there are strong authentication methods using OTP (One Time Password), there still has vulnerability from sophisticated attacks such as MITM (Man In The Middle). This letter proposes signing-based authentication protocol that copes with attacks, such as MITB (Man In The Browser), and provides non-repudiation function. The protocol shows generic method to prevent the sophisticated attacks through connecting advantages from OTP and PKI (Public Key Infrastructure) certificate, and that can be deployed to various extended form in internet banking.

• Journal of Internet Computing and Services
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• v.4 no.1
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• pp.19-25
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• 2003

Mobile IPv6 services exposes its vulnerability when a mobile node is roaming across the subnets which belongs to the different domains. The AAA Infrastructure Is strongly recommended when the ISPs need to authenticate the mobile user come from the different domains. In addition to the basic requirements for AAA service, the authentication latency and AAA message overhead should be minimized for contiguity of the service. This paper considers the roaming service with AAA infra structure in Mobile IPv6 and proposes the key distribution method to authenticate the mobile node with secure manner by reducing and optimizing the exchanged messages for AAA entities.

• Convergence Security Journal
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• v.16 no.4
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• pp.53-61
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• 2016

A number of countries have been developing and implementing national cybersecurity strategy to prevent damages caused by cyber threats and to minimize damages when they happened. However, there are a lot of differences and disparities in respective strategies with their own background and needs. A vulnerability in some places can be a global problem, so various guidelines have been developed by relevant organizations including international organizations to support the establishment of national cybersecurity strategies and improvement of them. In this paper, with analysis on the guidelines for the establishment of national cybersecurity strategies, reference model consisting of common elements of strategies was suggested. And several recommendations for the improvement measures for Korean national cybersecurity strategies were explained with a comparison of the reference model.

• The Journal of Society for e-Business Studies
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• v.8 no.4
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• pp.167-181
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• 2003

The contents for multimedia are very activated along to revolution of Internet. So this fact allows the contents for multimedia to be commercialized. These contents , however, included much vulnerability that it is difficult to be commercialized because attackers easily reproduce that. Many developers want to use watermarking method as the technique to protect the contents for multimedia, but it is very vulnerable to use only one method. This paper proposes the Secure DRM system which protects the contents for multimedia using Public Key Infrastructure and steganography methods. The SDRM system is more powerful than general DRM systems in that it has the special feature of watermarking and steganography techniques. We can prevent the attackers from reproducing and stealing the contents illegally, and authenticating users through SDRM systems.