• Journal of Korea Water Resources Association
• /
• v.46 no.10
• /
• pp.977-987
• /
• 2013

This study aims to develop a multiple criteria decision making (MCDM) approach for flood vulnerability assessment which considers uncertainty. The flood vulnerability assessment procedure consists of three steps: (1) use the Delphi process to determine the criteria and their corresponding weights-the adopted criteria represent the social, economic, and environmental circumstances related to floods, (2) construct a fuzzy data matrix for the flood vulnerability criteria using fuzzification and standardization, and (3) set priorities based on the number of assessed vulnerabilities. This study uses a modified fuzzy TOPSIS method based on ${\alpha}$-level sets which considers various uncertainties related to weight derivation and crisp data aggregation. Further, Spearman's rank correlation analysis is used to compare the rankings obtained using the proposed method with those obtained using fuzzy TOPSIS with fuzzy data, TOPSIS, and WSM methods with crisp data. The fuzzy TOPSIS method based on ${\alpha}$-cut level sets is found to have a higher correlation rate than the other methods, and thus, it can reduce the difference of the rankings which uses crisp and fuzzy data. Thus, the proposed flood vulnerability assessment method can effectively support flood management policies.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.24 no.4
• /
• pp.625-634
• /
• 2014

Tactical networks is being operated in configuration that consisting of a variety of characteristics communication equipments and heterogeneous networks. In this configurations, end-to-end communication can be achieved using interworking gateway for converting the data format of the network and using encryption algorithm of the networks. The use of mechanism results in a problem that secure data cannot be transferred directly, reprocessing and processing delay of communication in heterogeneous tactical networks. That is, for encoding and decoding of data, the decryption of encrypted data and re-encryption processing must be required at the gateway between different networks. In this paper proposes to mechanism for end-to-end secure communication in heterogeneous tactical networks. Using the proposed method, end-to-end secure communication between heterogeneous tactical networks(PSTN-UHF networks) which removes the necessity of a gateway for converting data into data formats suitable for network to remove a transmission delay factor and enable real-time voice and data communication and achieve end-to-end security for heterogeneous tactical networks. we propose a novel mechanism for end-to-end secure communication over PSTN and UHF networks and evaluate against the performance of conventional mechanism. Our proposal is confirmed removal of security vulnerabilities, end-to-end secure communication in heterogeneous tactical networks.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.40 no.10
• /
• pp.1994-2005
• /
• 2015

Voice over IP (VoIP) is a technology for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks. Instead of being transmitted over a circuit-switched network, however, the digital information is packetized, and transmission occurs in the form of IP packets over a packet-switched network which consist of several layers of computers. VoIP Service that used the various techniques has many advantages such as a voice Service, multimedia and additional service with cheap cost and so on. But the various frauds arises using VoIP because VoIP has the existing vulnerabilities at the Internet and based on complex technologies, which in turn, involve different components, protocols, and interfaces. According to research results, during in 2012, 46 % of fraud calls being made in VoIP. The revenue loss is considerable by fraud call. Among we will analyze for Toll Bypass Fraud by the SIM Box that occurs mainly on the international call, and propose the measures that can detect. Typically, proposed solutions to detect Toll Bypass fraud used DPI(Deep Packet Inspection) based on a variety of detection methods that using the Signature or statistical information, but Fraudster has used a number of countermeasures to avoid it as well. Particularly a Fraudster used countermeasure that encrypt VoIP Call Setup/Termination of SIP Signal or voice and both. This paper proposes the solution that is identifying equipment of Toll Bypass fraud using those countermeasures. Through feature of Voice traffic analysis, to detect involved equipment, and those behavior analysis to identifying SIM Box or Service Sever of VoIP Service Providers.

• The Journal of the Convergence on Culture Technology
• /
• v.6 no.4
• /
• pp.195-201
• /
• 2020

COVID-19 is hitting the world. In order to bring about new ways of innovation in the space sector, we need to analyze changes in the space sector and design new challenge strategies. COVID-19 exposes inherent vulnerabilities in the space sector. In particular, COVID-19 is causing supply chain shocks in the space industry, resulting in delays in the supply of systems, subsystems and parts due to a complete or partial interruption of a manufacturing unit. As the overall impact of New Normal on the industry is overall, we continue to look at it in the space sector. COVID is causing supply chain shock in the space industry. It causes a delay in the supply of systems, subsystems and parts due to a complete or partial interruption of a manufacturing unit. In the supply of launch services, the launch schedule is being delayed, but the main launch is still taking place. Demand for major applications such as environmental monitoring is soaring in the earth observation utilization sector. Analyzing the impact on manufacturing, the vendor-based contraction is bringing delays in the supply of systems, subsystems and components, and launch service providers are trying to minimize delays in the launch schedule.

• The Journal of Society for e-Business Studies
• /
• v.20 no.3
• /
• pp.47-58
• /
• 2015

Recently, new information security vulnerabilities have proliferated with the convergence of information security environments and information and communication technology. Accordingly, new types of cybercrime are on the rise, and security breaches and other security-related incidents are increasing rapidly because of security problems like external cyberattacks, leakage by insiders, etc. These threats will continue to multiply as industry and technology converge. Thus, the main purpose of this paper is to design and present security subjects in order to train professional security management talent who can deal with the enhanced threat to information. To achieve this, the study first set key information security topics for business settings on the basis of an analysis of preceding studies and the results of a meeting of an expert committee. The information security curriculum taxonomy is developed with reference to an information security job taxonomy for domestic conditions in South Korea. The results of this study are expected to help train skilled security talent who can address new security threats in the future environment of industrial convergence.

• Journal of the Korea Society of Computer and Information
• /
• v.17 no.12
• /
• pp.169-177
• /
• 2012

In the development process of application systems, the most important works are analysis and design. Most of the application systems are implemented on database system. So, database design is important. Also, IT System are confronted with more and more attacks by an increase interconnections between IT systems. Therefore security-related processes belong to a very important process. Security is a complex non-functional requirement that can interaction of many parts in the system. But Security is considered in the final stages of development. Therefore, Their increases the potential for the final product to contain vulnerabilities. Accordingly, Early in development related to security analysis and design process is very important. J2EE gives a solution based on RBAC((Role Based Access Control) for security and object-relational database also has RBAC for security. But there is not a object-oriented analysis and design methodology using RBAC of J2EE and object-relational database for security. In this paper, the unified object-oriented analysis and design methodology is developed for security-critical web application systems based on J2EE and object-relational database. We used UMLsec and RBAC of object-relational database and J2EE for this methodology.

• Journal of the Korea Convergence Society
• /
• v.8 no.9
• /
• pp.1-7
• /
• 2017

As the network environment develops and speeds up, a lot of smart devices is developed, and a high-speed smart society can be realized while allowing people to interact with objects. As the number of things Internet has surged, a wide range of new security risks and problems have emerged for devices, platforms and operating systems, communications, and connected systems. Due to the physical characteristics of IoT devices, they are smaller in size than conventional systems, and operate with low power, low cost, and relatively low specifications. Therefore, it is difficult to apply the existing security solution used in the existing system. In addition, IoT devices are connected to the network at all times, it is important to ensure that personal privacy exposure, such as eavesdropping, data tampering, privacy breach, information leakage, unauthorized access, Significant security issues can arise, including confidentiality and threats to facilities. In this paper, we investigate cases of security threats and cases of network of IoT, analyze vulnerabilities, and suggest ways to minimize property damage by Internet of things.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.29 no.6
• /
• pp.1243-1257
• /
• 2019

With the emergence of the IoT environment, various smart devices provide consumers with the convenience and various services. However, as security threats such as invasion of privacy have been reported, the importance of security issues in the IoT environment has emerged, and in particular, the security problem of key management has been discussed, and the PUF has been discussed as a countermeasure. In relation to the key management problem, a protocol using MIPUF has been proposed for the security problem of the group key management system. The system can be applied to lightweight IoT environments and the safety of the PUF ensures the safety of the entire system. However, in some processes, it shows vulnerabilities in terms of safety and efficiency of operation. This paper improves the existing protocol by adding authentication for members, ensuring data independence, reducing unnecessary operations, and increasing the efficiency of database searches. Safety analysis is performed for a specific attack and efficiency analysis results are presented by comparing the computational quantities. Through this, this paper shows that the reliability of data can be improved and our proposed method is lighter than existing protocol.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2011.10a
• /
• pp.255-258
• /
• 2011

Wi-Fi is a rapidly spreading communications network with Smart phone's publication, the technology has become Ubiquitous-based core network which is connected to personal computers, laptops, and tablet PC. Wi-Fi can send currently a variety of data standard due to developed wireless LAN communications network. One of Wi-Fi standard protocols, which is IEEE 802.11n, use 2.4GHz and 5GHz band. 2.4GHz band is used for 802.11b/g protocol because wavelength is long, diffraction and receiving distance is enough to connect other device. 5GHz band has more available channels to use than 2.4GHz band, so there is no frequency interference of other wireless device such as Bluetooth, RFID. Moreover, there is low interference between channels due to small users in each bandwidth level. In the thesis, we are going to analyze 802.11a/b/g protocol which has used since the beginning of Wi-Fi protocol and 802.11n protocol which is used lately. Furthermore, we look into development and direction for standardization of the next generation wireless LANs which are 802.11ac and 802.11ad. In addition, we will consider for the security, vulnerabilities and its countermeasure in Wireless LAN.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.27 no.6
• /
• pp.815-821
• /
• 2021

This study addresses on the design of performance monitoring system for the time synchronization service of the enhanced long-range navigation (eLoran) system, which has a representative ground-wave radio broadcast system capable of providing positioning, navigation, timing and data (PNT&D) services. The limitations of time-synchronized systems due to the signal vulnerabilities of the global navigation satellite system (GNSS) are explained, and the performance monitoring system for the eLoran timing service as a backup to the GNSS is proposed. The time synchronization service using eLoran system as well as system configurations and the user requirements in the differential Loran (dLoran) system are described to monitor the time synchronization performance. The results of the designed system are presented for long-term operation in the eLoran testbed environment. As the results of time performance monitoring, we were able to verify the time synchronization precision within 43.71 ns without corrections, 22.52 ns with corrections. Based on these results, the eLoran system can be utilized as a precise time synchronization source for GPS timing backup.