• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.34 no.1
• /
• pp.129-141
• /
• 2024

Amidst the acceleration of digital transformation across various sectors, the financial market is increasingly focusing on the development of digital and electronic payment methods, including currency. Among these, Central Bank Digital Currencies (CBDC) are emerging as future digital currencies that could replace physical cash. They are stable, not subject to value fluctuation, and can be exchanged one-to-one with existing physical currencies. Recently, both domestic and international efforts are underway in researching and developing CBDCs. However, current CBDC systems face scalability issues such as delays in processing large transactions, response times, and network congestion. To build a universal CBDC system, it is crucial to resolve these scalability issues, including the low throughput and network overload problems inherent in existing blockchain technologies. Therefore, this study proposes a solution based on reinforcement learning for handling large-scale data in a CBDC environment, aiming to improve throughput and reduce network congestion. The proposed technology can increase throughput by more than 64 times and reduce network congestion by over 20% compared to existing systems.

• Korean Journal of Social Welfare Studies
• /
• v.44 no.3
• /
• pp.147-175
• /
• 2013

The purpose of this study is to examine the effects of the organizational characteristics and interorganizational network level on social welfare organizationas' effectiveness using structural equation model. For achieving this purpose, this study defined organizational effectiveness as financial, human and physical resource capability according to resource systems approach. Organizational characteristics variables included the number of qualified staff, degree of resource dependency, the proportion of government subsidies, the main organizational philosophy, establishment year, the attitude of top manager and the number of informal ties. Interorganizational network variables were divided by outdegree centrality and indegree centrality. The data collected from women's welfare organizations in Seoul through survey method. The analysis tools used the UCINET 6.245 for the network analysis and AMOS 18.0 for the structural equation model. The results of this study are as follows. The factors affected on the financial resource capacity were the number of qualified staff, the proportion of government subsides and the indegree centrality. Meanwhile, only indegree centrality directly influenced on the human resource capability. The significant affecting factors on physical resource capacity were the number of qualified staff, the attitude of top manager and informal ties. Based on these results, the implications of this study and the ways to enhance social welfare organization's effectiveness were discussed.

• Journal of Internet Computing and Services
• /
• v.12 no.5
• /
• pp.47-61
• /
• 2011

Recently, the importance of digital forensic has been magnified because of the dramatic increase of cyber crimes and the increasing complexity of the investigation of target systems such as PCs, servers, and database systems. Moreover, some systems have to be investigated with live forensic techniques. However, even though live forensic techniques have been improved, they are still vulnerable to anti-forensic activities when the target systems are remotely accessible by criminals or their accomplices. To solve this problem, we first suggest a layer-based model and the anti-forensic scenarios which can actually be applicable to each layer. Our suggested model, the Anti-Forensic Activites layer-based model, has 5 layers - the physical layer, network layer, OS layer, database application layer and data layer. Each layer has possible anti-forensic scenarios with detailed commands. Second, we propose a fuzzy expert system for effectively detecting anti-forensic activities. Some anti-forensic activities are hardly distinguished from normal activities. So, we use fuzzy logic for handling ambiguous data. We make rule sets with extracted commands and their arguments from pre-defined scenarios and the fuzzy expert system learns the rule sets. With this system, we can detect anti-forensic activities in real time when performing live forensic.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.24 no.1
• /
• pp.97-106
• /
• 2014

CCTV(Closed Circuit television) is one of the widely used physical security technologies and video acquisition device installed at specific point with various purposes. Recently, as the CCTV capabilities improve, facial recognition from the information collected from CCTV video is under development. However, in case these technologies are exploited, concerns on major privacy infringement are high. Especially, a computer connected to a particular space images taken by the camera in real time over the Internet has emerged to show information services. In the privacy law, safety measures which is related with biometric template are notified. Accordingly, in this paper, for the protection of privacy video information in the video surveillance system, the technical and managerial requirements for video information security are suggested.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.39 no.3
• /
• pp.147-155
• /
• 2016

Industry 4.0's goal is the 'Smart Factory' that integrates and controls production process, procurement, distribution and service based on the fundamental technology such as internet of the things, cyber physical system, sensor, etc. Basic requirement for successful promotion of this Industry 4.0 is the large supply of semiconductor. However, company I who produces dicing blades has difficulty to meet the increasing demand and has hard time to increase revenue because its raw material includes high price diamond, and requires very complex and sensitive process for production. Therefore, this study is focused on understanding the problems and presenting optimal plan to increase productivity of dicing blade manufacturing processes. We carried out a study as follows to accomplish the above purposes. First, previous researches were investigated. Second, the bottlenecks in manufacturing processes were identified using simulation tool (Arena 14.3). Third, we calculate investment amount according to added equipments purchase and perform economic analysis according to cost and sales increase. Finally, we derive optimum plan for productivity improvement and analyze its expected effect. To summarize these results as follows : First, daily average blade production volume can be increased two times from 60 ea. to 120 ea. by performing mixing job in the day before. Second, work flow can be smoother due to reduced waiting time if more machines are added to improve setting process. It was found that average waiting time of 23 minutes can be reduced to around 9 minutes from current process. Third, it was found through simulation that the whole processing line can compose smoother production line by performing mixing process in advance, and add setting and sintering machines. In the course of this study, it was found that adding more machines to reduce waiting time is not the best alternative.

• The Journal of Bigdata
• /
• v.4 no.1
• /
• pp.39-51
• /
• 2019

With the advent of the fourth industrial revolution characterized by hyperconnectivity and superintelligence and the emerging cyber physical systems, enormous volumes of data are being generated in the cyberspace every day ranging from the records about human life and activities to the communication records of computers, information and communication devices, and the Internet of things. Big data represented by 3Vs (volume, velocity, and variety) are actively used in the defence field as well. This paper proposes a big data governance model to support effective military operations in the cyberspace. Cyberspace operation missions and big data types that can be collected in the cyberspace are classified and integrated with big data governance issues to build a big data governance framework model. Then the effectiveness of the constructed model is verified through examples. The result of this study will be able to assist big data utilization planning in the defence sector.

• Smart Structures and Systems
• /
• v.20 no.5
• /
• pp.619-636
• /
• 2017

Magnetorheological (MR) damper is a type of controllable device widely used in vibration mitigation. This device is highly nonlinear, and exhibits strongly hysteretic behavior that is dependent on both the motion imposed on the device and the strength of the surrounding electromagnetic field. An accurate model for understanding and predicting the nonlinear damping force of the MR damper is crucial for its control applications. The MR damper models are often identified off-line by conducting regression analysis using data collected under constant voltage. In this study, a MR damper model is integrated with a model for the power supply unit (PSU) to consider the dynamic behavior of the PSU, and then a real-time nonlinear model updating technique is proposed to accurately identify this integrated MR damper model with the efficiency that cannot be offered by off-line methods. The unscented Kalman filter is implemented as the updating algorithm on a cyber-physical model updating platform. Using this platform, the experimental study is conducted to identify MR damper models in real-time, under in-service conditions with time-varying current levels. For comparison purposes, both off-line and real-time updating methods are applied in the experimental study. The results demonstrate that all the updated models can provide good identification accuracy, but the error comparison shows the real-time updated models yield smaller relative errors than the off-line updated model. In addition, the real-time state estimates obtained during the model updating can be used as feedback for potential nonlinear control design for MR dampers.

• Journal of Digital Contents Society
• /
• v.19 no.2
• /
• pp.293-300
• /
• 2018

This study explored the security of Industry 4.0 such as security trends and security threats in Industry 4.0, and security system in Industry 4.0. The threat elements in Industry 4.0 are changing from ICT to IoT and to CPS security, so security paradigm and security System should change accordingly. In particular, environmental and administrative security are more important to solve CPS security. The fourth industry-age security should change to customized security for individual systems, suggesting that the security technology that combines hardware and software in product production design should change from the beginning of development. The security system of the fourth industry proposes design and implementation as a CPS security system as a security system that can accommodate various devices and platforms from a security system in a single system such as a network to an individual system.

• Journal of Digital Convergence
• /
• v.19 no.8
• /
• pp.241-247
• /
• 2021

As a way to solve the side effects of urban development, a smart city with information and communication technology converges in the city is being built. For this, a smart city platform should support the development and integration of smart city services. Therefore, the underlying technology and the functional and non-functional requirements that the smart platform must support were analyzed. As a result of this, we classified the Internet of Things, cloud computing, big data and cyber-physical systems into four categories as the underlying technologies supported by the smart city platform, and derived the functional and non-functional requirements that can be implemented and the reference model of the smart city platform. The reference model of the smart city platform is used for decision-making on investment in infrastructure technology and the development scope of services according to functional or non-functional requirements to solve specific city problems for city managers. It provides platform developers with guidelines to identify and determine the functional and non-functional requirements and implementation technologies of software platforms for building smart cities.

• International Journal of Computer Science & Network Security
• /
• v.24 no.6
• /
• pp.207-215
• /
• 2024

Cloud computing is now used by most companies, business centres and academic institutions to embrace new computer technology. Cloud Service Providers (CSPs) are limited to certain services, missing some of the assets requested by their customers, it means that different clouds need to interconnect to share resources and interoperate between them. The clouds may be interconnected in different characteristics and systems, and the network may be vulnerable to volatility or interference. While information technology and cloud computing are also advancing to accommodate the growing worldwide application, criminals use cyberspace to perform cybercrimes. Cloud services deployment is becoming highly prone to threats and intrusions. The unauthorised access or destruction of records yields significant catastrophic losses to organisations or agencies. Human intervention and Physical devices are not enough for protection and monitoring of cloud services; therefore, there is a need for more efficient design for cyber defence that is adaptable, flexible, robust and able to detect dangerous cybercrime such as a Denial of Service (DOS) and Distributed Denial of Service (DDOS) in heterogeneous cloud computing platforms and make essential real-time decisions for forensic investigation. This paper aims to develop a framework for digital forensic for the detection of cybercrime in a joined heterogeneous cloud setup. We developed a Digital Forensics model in this paper that can function in heterogeneous joint clouds. We used Unified Modeling Language (UML) specifically activity diagram in designing the proposed framework, then for deployment, we used an architectural modelling system in developing a framework. We developed an activity diagram that can accommodate the variability and complexities of the clouds when handling inter-cloud resources.