• Journal of the Korea Institute of Information Security & Cryptology
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• v.32 no.4
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• pp.723-736
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• 2022

Steganography is being used as a means of secret communication for crimes that threaten national security such as terrorism and espionage. With the development of computers, steganography technologies develop and criminals produce and use their own programs. However, the research for steganography is not active because detailed information on national security cases is not disclosed. The development of investigation technologies and the responses of criminal law are insufficient. Therefore, in this paper, the detection and decoding process was examined for steganography investigation, and the method was analyzed for 'the spy case of Pastor Kim', who was convicted by the Supreme Court. Multiple security devices were prepared using symmetric steganography using the pre-promised stego key. Furthermore, the three criminal legal issues: (1) the relevance issue, (2) the right to participate, and (3) the public trial issue a countermeasure were considered in national security cases. Through this paper, we hope that the investigative agency will develop analysis techniques for steganography.

• Journal of forensic and investigative science
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• v.2 no.1
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• pp.84-86
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• 2007

• The Science & Technology
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• s.528
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• pp.13-15
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• 2013

• The Science & Technology
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• s.528
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• pp.10-12
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• 2013

• The Science & Technology
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• s.528
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• pp.21-24
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• 2013

• Journal of Digital Forensics
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• v.12 no.3
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• pp.109-120
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• 2018

The smartphone is the communication device that is the most personal to the user, and it keeps a lot of information related to the user and makes information communication with other devices. With these characteristics, forensics on smartphones are one of the most basic methods of investigation in criminal investigations, and have actually contributed to the settlement of the case by providing many clues. However, recently, it is designed to encrypt data stored as a social issue related to the protection of user's personal information, or to delete deleted data or to delete log data together. So, any solutions? In this paper, I try to find the answer from cloud data stored by smartphone user account. Cloud forensics should approach complementary relationships rather than smartphone forensics. There are a lot of data stored in the cloud that can be meaningfully used in the investigation. Online activity information of users, such as Internet usage, YouTube view, and contents purchase information, cloud service such as e-mail, cloud drive, and location information are the most representative data. These data can be unvaluable, but here are some important clues in various types of criminal investigations. In this paper, I propose a method to extract data from the google cloud so that the data can be used for investigation, and to utilize the extracted data for investigation. And it explains the role of the extracted artifacts in the actual investigation business through virtual cases and proves its value.

• Korean Journal of Forensic Psychology
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• v.13 no.1
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• pp.75-97
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• 2022

Profiling is recognized as a representative application area of domestic criminal psychology, and the National Police Agency profiler is firmly established as a profession. However, compared to the social awareness, the recognition and utilization within the police is not high. In this study, we tried to identify factors affecting the intention to use profiling by identifying the perception of investigators who request and use profiling from a profiler when a violent incident occurs. To this end, the relationship between the perception of the importance of factors considered by investigators in the criminal investigation process and the attitude toward profiling on the intention to use profiling was verified through the path model. As a result of a survey of 340 police investigators, the investigator's perception of the importance of investigation elements was divided into two factors: the importance of normative investigative elements (evidence collection and legal judgment, etc.) and factual investigative elements (criminal analysis, criminal information system analysis, etc.). Among them, the importance of factual investigative elements were found to have a positive effect on the intention to use it by mediating the attitude toward profiling. On the other hand, in the case of the importance of normative investigative elements, it was found to have a negative effect on the attitude toward profiling. These results suggest that the perception that investigators have about investigation, which is their main work area, plays a role in determining whether to request profiling as well as attitude towards profiling. Based on the research results, strategies necessary to activate the use of profiling were discussed.

• Communications of Mathematical Education
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• v.38 no.2
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• pp.145-165
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• 2024

The purpose of this study is to analyze the types of errors made by Korean language learners in the use of dual numerals and provides basic data for developing an effective teaching numeration using dual numerals. To this end, a case study was conducted to analyze the types of errors that appear in numeration using dual numerals targeting Korean language learners with diverse linguistic and cultural backgrounds and different academic achievements in Korean and mathematics. Error types that categorized errors made by Korean language learners were used as an analysis framework. The conclusions obtained from the research results are as follows. First, it is necessary to provide students with opportunities to use them frequently so that they can become familiar with the use of native language numerals, which often causes errors. Second, when teaching Korean language learners with low-level Korean language academic achievement how to use Chinese numerals, it is necessary to pay attention to the multiplicative numeral system of Chinese numerals. Third, it is necessary to teach children to accurately read foreign word classifiers used with Chinese numerals accurately in Korean and distinguish between the classifiers 'o'clock' and 'hours'. There is a need to provide guidance so that native language/Chinese numerals can be used appropriately in succession along with Chinese classifiers. The results of this study may contribute to the development of an effective teaching numeration using dual numerals for Korean language learners with diverse linguistic and cultural backgrounds.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2007.02a
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• pp.146-149
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• 2007

2000년대에 접어들어 컴퓨터가 보급화 되면서, 컴퓨터를 도구로 하는 범죄가 폭발적으로 증가하기 시작하였다. 컴퓨터 시스템에 접근하여 중요 정보를 빼돌리거나, 범죄의 목적이 되는 해킹과 같은 정보보호 침해사고가 크게 증가하였으며, 컴퓨터를 이용한 정상적인 서비스를 방해하는 형태의 디지털 범죄들이 다수 발생하기 시작하였다. 따라서 범죄 수사 과정에서 전자 매체에 대한 분석이 필수 불가결한 요소로 등장하고 있으며, 이를 분석하려는 디지털 포렌식 연구가 활발히 진행되고 있다. 특히 전자 매체에 기록되는 디지털 정보는 보관이 편리하지만 삭제와 복제가 용이하므로 디지털 증거는 매우 세심하게 다루어야 하며, 수사관에 의한 의도적인 훼손이 없었음을 증명할 수 있는 절차와 제도가 필요하다. 국내에서는 적법한 수사 절차와 무결성을 보장하기 위하여 '절차 연속성(chain-of-custody)'을 제공하는 수사 가이드라인을 제작하였으며, 체계적인 수사를 수행 하고 있다.[4] 이와 더불어 포렌식 수사 과정에서 물리적인 접근을 통해 디지털 저장 매체에 대한 복구할 수 있는 방법이 존재하며, 이에 대한 구체적인 방안을 논한다.[1]

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.6
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• pp.15-20
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• 2019

Fundamental processes in digital forensic investigation - such as disk imaging - were developed when digital investigation was relatively young. As digital forensic processes and procedures matured, these fundamental tools, that are the pillars of the reset of the data processing and analysis phases of an investigation, largely stayed the same. This work is a study of modern digital forensic imaging software tools. Specifically, we will examine the feature sets of modern digital forensic imaging tools, as well as their development and release cycles to understand patterns of fundamental tool development. Based on this survey, we show the weakness in current digital investigation fundamental software development and maintenance over time. We also provide recommendations on how to improve fundamental tools.