• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2002.11a
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• pp.266-269
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• 2002

As a simulation or replacement of analog money in cyber space, the e-cash was introduced by using cryptographic primitives. Since a perfect anonymity system causes some illegal activities, such as money laundering, blackmailing, and illegal purchase, a revocable electronic system was paid a great attention to control the anonymity. In general, Trust Third Party(TTP) is introduced to detect any dubious user and coin, namely user tracing and coin tracing. In this paper we propose a new revocable anonymity e-cash system, and verify the security requirement as well. In our scheme a user first withdraws the e-coin from bank by using blind signature, and then TTP verifies the bank's signature and records the tracing information.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.9 no.4
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• pp.85-97
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• 1999

A blind signature scheme is a protocol allowing verifier to obtain a valid signature for a message m from a signer without him seeing the message. This means that the bank in collaboration with the shop cannot trace the electronic cash to user. However anonymous electronic cash also facilitates fraud and criminal acts such as money laundering anonymous blackmailing and illegal purchaes. Therefore in this paper we propose fair blind signature scheme based on KCDSA which is a domestic digital signature scheme and it apply a electronic cash system. In particularly a proposed electronic cash system have an anonymity control ability which trace a user who make use a electronic cash illegally in association with a trusted center.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.585-594
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• 2018

Virtual currencies have emerged along with new technologies such as block chain, artificial intelligence (AI), and big data. This study examines the benefits of a security-enhanced block chain resulting from individual trading, decentralized from governments, as well as the problems associated with misuse of virtual currencies. Virtual currencies, due to its anonymity, is vulnerable to financial crimes, such as ransom-ware, fraud, drug trafficking, tax evasion and money laundering. Use of virtual currencies can facilitate criminals avoid detection from investigative agencies. Government regulatory policy continues to address these concerns, and the virtual currency exchange has also announced a self-regulation proposal. However, a fundamental solution remains necessary. The purpose of this paper is to investigate the problems regarding abuse of virtual currency and to identify a practical system for transactions involving virtual currencies. However, in order to promote transactions involving virtual currencies and to institutionalize a governance system, multilateral cooperation is required. Although the restricting the use of virtual currencies regarding minors and foreign trade, as well as the introduction of a real-name system are considered promising prospects, many problems remain. Virtual currency is not a simple digital item but a method of redesigning the function of money. Coordinated efforts are needed globally to be able to further activate the positive aspects concerning the use of virtual currencies.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.9 no.1
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• pp.29-46
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• 1999

Most of the previous researches for the electronic cash system guarantee unconditional untraceability for the purpose of individual privacy. Such untraceable electronic cash system that only focuses on untraceability, however, has side effect such as money laundering, criminal activities. We present a escrow cash model using anonymous channel that supports not only untaceability but also crime prevention, and prove the efficiency of our scheme relative to previous escrow cash systems.

• International Journal of Computer Science & Network Security
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• v.22 no.10
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• pp.145-154
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• 2022

Based on the obtained results of the study, the most problematic issues and legal conflicts are identified, which are related to the ratio of norms of domestic and foreign legislation, taking into account the requirements of the Constitution of Ukraine and the provisions of the Law of Ukraine "On international agreements". Along with this, it is stated in this scientific article that there are a number of provisions and examples of positive practice on the specified topic abroad and in international legal acts today, which should be used by Ukraine both in improving legislation on the issues of banking activity and in increasing the level of criminal legal protection of relevant critical infrastructure facilities, especially those that are substantively related to prevention and counteraction of activity, with regard to the legalization (laundering) of criminally obtained funds, financing of terrorism and the financing of the proliferation of weapons of mass destruction, which is quite relevant for our state, given the military conflict that is taking place on its territory in the Donbass. Again, in the same context, the need for more active cooperation between Ukraine and the FATF (international body developing a policy to combat money laundering) has been proven.

• Journal of the Society of Disaster Information
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• v.18 no.1
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• pp.218-227
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• 2022

Purpose: In the case of cavity discovered by ground penetrating radar exploration, it is necessary to accurately predict the filling amount in the cavity in advance, fill the cavity sufficiently and exert strength to ensure stability and prevent ground subsidence. Method: The cavity waveform analysis method by GPR exploration and the method using the cavity shape imaging equipment were performed to measure the cavity shape with irregular size and shape of the actual cavity, and the amount of cavity filling of the injection material was calculated during rapid restoration. Result: The expected filling amount was presented by analyzing the correlation between the cavity size and the filling amount of injection material according to the cavity scale and soil depth through the method by GPR exploration and the cavity scale calculation using the cavity shaping equipment. Conclusion: The cavity scale measured by the cavity imaging equipment was found to be in the range of 20% to 40% of the cavity scale by GPR exploration. In addition, the filling amount of injection material compared to the cavity scale predicted by GPR exploration was in the range of about 60% to 140%, and the filling amount of the injection material compared to the cavity size by the cavity shaping equipment was confirmed to be about 260% to 320 Purpose: The purpose of this study is to examine the types of crimes taking place in the metaverse, and to establish a crime prevention strategy and find a legal deterrent against it. Method: In order to classify crime types in the metaverse, crime types were analyzed based on the results of previous studies and current incidents. Result: Most of the crimes taking place in the metaverse are done in games such as Roblox or Zeppetto. Most of the game users were teenagers. Looking at the types, there are many teens for sexual crimes, violent crimes, and defamation, but professional criminals are often included in copyright infringement, money laundering using virtual currency, and fraud. Conclusion: Since the types of crimes in the metaverse are diverse, various institutional supplementary mechanisms such as establishment of police crime prevention strategies, legal regulations, and law revisions will have to be prepared.

• Journal of Information Processing Systems
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• v.16 no.4
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• pp.935-958
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• 2020

The core value of finance is credit. It can be said that without credit, there can be no finance. The distributed structure of the blockchain and the low-cost trust-building mechanism based on mathematical algorithms provide a new solution and path for solving and optimizing related problems in the financial field. The blockchain technology is applied in the development of the financial industry through consensus mechanisms, smart contracts, and distributed networks. In this research, a comprehensive survey of the blockchain technology is proposed in the development of financial services including equity crowdfunding and credit investigations in inclusive finance, cross-border remittance, Internet financial payment, P2P lending, supply chains finance, and the application of blockchain in the field of anti-money laundering. This paper discusses the role of blockchain in solutions to different issues in the financial field. It also discusses the architectures in different financial service application scenarios from the perspective of the financial trust mechanism and the perspective of the technology and rule change of blockchain participation in financial innovation. Finally, the problems and challenges of blockchain in financial services are discussed, and corresponding solutions are proposed.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.17 no.5
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• pp.141-146
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• 2007

Barcodes have been widely used to implement automatic identification systems but there are various problems such as security weakness or distance restriction in scanning barcode signals in a barcode-based automatic identifcation systems. Recently researchers are gradually interested in radio frequency identification (RFID) and RFID systems have been applied to various fields than before. Especially one of RFID application fields, a bank system uses RFID tagged bankontes to prevent illegal transactions such as counterfeiting banknotes and money laundering. In this paper, we propose a RFID system for protecting location provacy of a banknote holder. In addition, our paper describes that a trust party can trace a counterfeit banknote holder to provide against emergencies.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.22 no.3
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• pp.585-600
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• 2012

Security issues in online games are increasing as the online game industry grows. Real money trading (RMT) by online game users has become a security issue in several countries including Korea because RMT is related to criminal activities such as money laundering or tax evasion. RMT-related activities are done by professional work forces, namely gold-farmers, and many of them employ the automated program, bot, to gain cyber asset in a quick and efficient way. Online game companies try to prevent the activities of gold-farmers using game bots detection algorithm and block their accounts or IP addresses. However, game bot detection algorithm can detect a part of gold-farmer's network and IP address blocking also can be detoured easily by using the virtual private server or IP spoofing. In this paper, we propose a method to detect gold-farmer groups by analyzing their connection patterns to the online game servers, particularly information on their routing and source locations. We verified that the proposed method can reveal gold-farmers' group effectively by analyzing real data from the famous MMORPG.

• KNOM Review
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• v.21 no.2
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• pp.18-25
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• 2018

Since the development of block-chain technology by Satoshi Nakamoto and Bitcoin pioneered a new cryptocurrency market, a number of scale of cryptocurrency have emerged. There are crimes taking place using the anonymity and vulnerabilities of block-chain technology, and many studies are underway to improve vulnerability and prevent crime. However, they are not enough to detect users who commit crimes. Therefore, it is very important to detect abnormal behavior such as money laundering and stealing cryptocurrency from the network. In this paper, the characteristics of the transactions and user graphs in the Bitcoin network are collected and statistical information is extracted from them and presented as plots on the log scale. Finally, we analyze visualized plots according to the Densification Power Law and Power Law Degree, as a result, present features appropriate for detection of anomalies involving abnormal transactions and abnormal users in the Bitcoin network.