• Journal of Science Criminal Investigation
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• v.11 no.4
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• pp.276-282
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• 2017

As evidence that can be obtained at the crime scene, the importance of micro-evidences has been recognized in recent years with the development modern molecular-level analytical techniques. These micro-evidences include substances useful for personal identification such as DNA, but it is difficult to collect only the evidences showing individual characteristics every time at the crime scene. Therefore, development of new research approaches for the discovery and application of micro-evidence candidates is in increasing demand. For this purpose, skin microbial communities of bacteria inhabiting the palms of 16 people were collected and terminal-restriction enzyme fragment length polymorphism (T-RFLP) analysis was carried out to examine the potential for the application in personal identification. As a result, 16 different electropherograms were obtained, and various taxa including Staphylococcus and Bacillus were shown to produce different T-RF profiles among individuals. These results were analyzed with the factors affecting the microbiota such as sex and working environment of individuals.

• Analytical Science and Technology
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• v.22 no.3
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• pp.235-246
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• 2009

The analyses of minor and trace elements in glass debris were performed using LA-ICP-MS in order to identify manufacturers using real commercial samples. At first, a calibration curve was made using standard glass samples of NIST 610, 612, 614 and 616. $^{29}Si$ was used as an internal standard, and the ratios of metal/Si for each metal were compared with their concentrations. Based on elements in each sample and standard materials, 24 metals were quantified and the LOD in analysis, according to the blank sample, was in the range of 0.11 mg/kg (Ti)-4.91 mg/kg (Ca). Eleven samples from two manufacturers were collected and five sub-samples were taken from each sample for analysis. 15 elements (Co, Ce, Ca, Mn, Sr, Ba, Li, Rb, U, La, Th, Na, Al, Zr and Hf) were selected to identify manufacturers because some elements (Cu, Cr, Cd and Ni) were below the detection limit and some elements (Ti, Pr, Mg, Nb, Nd) were absent in the analysis of standards and others (Pb and Sn) had a problem of homogeneity. The attempts to identify manufacturers and the manufacturing period were performed through a triangular diagram. In the manufacturer discrimination by discriminant analysis, a canonical discriminant function was made based on Mn, Ce and Rb, and each sample could be identified.

• Analytical Science and Technology
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• v.35 no.3
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• pp.129-135
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• 2022

We tested the pre-treatment of alumina, leucine, alumina mixed with leucine at ratios of 9:1 (Al-Leu (9:1)) and 5:1 (Al-Leu (5:1)), and alumina mixed with sodium lactate at a ratio of 5:1 (Al-Lac (5:1)) on aged fingerprints (1, 7, 14, and 30 days after natural fingerprinting) before cyanoacrylate (CA) fuming to improve the development efficacy. As a result of the experiment, fingerprints with pre-treatment of alumina, leucine, Al-Leu (9:1), Al-Leu (5:1), and Al-Lac (5:1) showed better development efficacy (area and minutiae) than fingerprints without pre-treatment. Therefore, this modified CA fuming method improved the development efficacy with five pretreatments.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.32 no.6
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• pp.1113-1120
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• 2022

Recently, the investigation has been difficult due to the emergence of messengers that encrypt and store data for the purpose of protecting personal information and provide services such as end-to-end encryption with a focus on security. Accordingly, the number of crime cases using security messengers is increasing, but research on data decoding for security messengers is needed. Element security messengers provide end-to-end encryption functions so that only conversation participants can check conversation history, but research on decoding them is insufficient. Therefore, in this paper, we analyze the instant messenger Element, which provides end-to-end encryption, and propose a plaintext verification of the history of encrypted secure chat rooms using decryption keys stored in the Windows Credential Manager service without user passwords. In addition, we summarize the results of analyzing significant general and secure chat-related artifacts from a digital forensics investigation perspective.

• Korean Journal of Cognitive Science
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• v.18 no.4
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• pp.457-483
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• 2007

Database Semantics (DBS) attempts to provide a comprehensive and integrated approach to human communication which seeks theory-implementation transparency. Two key components of DBS are Word bank as a data structure and left-Associative Grammar (LAG) as an algorithm. This study aims to provide a pilot implementation of Korean in DBS. First, it is shown how the three separate modules of grammar in DBS, namely, Hear, Think, and Speak, combine to form an integrated system that simulates a cognitive agent by making use of a simple Korean sentence as an example. Second, we provide a detailed analysis of the structure in Korean that is a characteristic of Korean involving numerals, classifiers, and nouns, thereby illustrating how DBS can be applied to Korean. We also discuss an issue raised in the literature concerning a problem that arises when we try to apply the LAG algorithm to the analysis of head-final language like Korean, and then discuss some possible solution to the problem.

• The Journal of Korean Association of Computer Education
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• v.17 no.3
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• pp.75-84
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• 2014

It is a current situation that a large number of physical and financial damages are increasing due to the growth of intellectual cyber crime and unexpected Internet incidents year by year. In the large scale security incidents, digital forensics techniques for computer crime investigations are essential to secure a place in the field. However, qualified digital forensics investigators who complete with digital security technology are practically insufficient in domestic. In this paper, as one of developing human resources plans regarding to scientific investigation of Internet security incidents, an undergraduate curriculum per stage in digital forensics was proposed. For the effective curriculum per stage, the interviews, group discussion on focused group of existing digital forensics investigators and related research were performed to select curriculum, and then the level of difficulty and practical suitability on each subject designed were analyzed through survey and interview to current investigators and security professionals. After collating the survey, the digital forensic curriculum per level was designed to highly adaptable workforce for the future for working and positive suggestions and proposals are addressed.

• The Journal of the Korea Contents Association
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• v.18 no.2
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• pp.124-131
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• 2018

This study aimed to compare effectiveness of fluorescent reagents for enhancing blood such as acid yellow 7, rhodamine 6G, eosin Y. AY7 and eosin Y have been introduced in Korea as fluorescent reagents for enhancing blood, but not rhodamine 6G. In this study, researchers photographed when each reagents gave the most effective results. Consequently, rhodamine 6G was superior to the others. Eosin Y enhanced bloody fingermarks weakly compared to AY7 and rhodamine 6G. Furthermore, the more depletion trials were done, the less effectiveness were shown. Therefore, researchers recommended that crime scene investigators try to use rhodamine 6G fluorescent reagents for enhancing blood.

• Convergence Security Journal
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• v.22 no.5
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• pp.21-35
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• 2022

The use of digital information according to the development of information and communication technology and the 4th industrial revolution is continuously increasing and diversifying, and in proportion to this, crimes using digital information are also increasing. However, there are few cases of establishing an environment for processing and analysis of digital evidence in Korea. The budget allocated for each organization is different and the digital forensics laboratory built without solving the chronic problem of securing space has a problem in that there is no standard that can be referenced from the initial configuration stage. Based on this awareness of the problem, this thesis conducted an exploratory study focusing on tools and equipment necessary for building a digital forensics laboratory. As a research method, focus group interviews were conducted with 15 experts with extensive practical experience in the digital forensic laboratory or digital forensics field and experts' opinions were collected on the following 9 areas: network configuration, analyst computer, personal tools·equipment, imaging devices, dedicated software, open source software, common tools/equipment, accessories, and other considerations. As a result, a list of tools and equipment for digital forensic laboratories was derived.

• Journal of The Korean Association For Science Education
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• v.35 no.3
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• pp.353-361
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• 2015

This study focused on the use of peer assessment activities to investigate its the impact on students' argumentation skills in argument-based inquiry. The participants of the study were 106 10th grade students (four classes). Two classes were assigned to the experimental group, and the other two classes were assigned to the comparative group. The experimental group was taught argument-based inquiry through the application of peer assessment activities. The comparative group was taught argument-based inquiry without peer assessments. At the claim and evidence stage, students were asked to evaluate whether peers' claims fit with the evidence and whether peers' explanation of the evidences validity was sufficient. The quality of argumentation used in the students' writing was different in each group. According to the analysis of the summary writing test, the results showed that the experimental group had a significantly higher mean score than the comparative group in argumentation components, including evidence and warrant/backing. In addition, the experimental group used better multimodal representation including explanation of evidence than the comparative group. The findings showed that argument-based inquiry applying peer assessment activities had an effect on the argumentation skills in students' writing.

• Journal of forensic and investigative science
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• v.2 no.2
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• pp.67-91
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• 2007

The nature of deaths occurred at sea may be revealed the differences from that in the land, but there is no comprehensive statistical analysis of deaths occurred at Korean Sea so far. Therefore, the cases of deaths or missing in the period 1993 - 2006 were analyzed by the cause, place of death, and results of preliminary investigation. In the period from 1993 to 2006, over 1000 peoples were died or missing every year. The cases of marine safety accidents including self-carelessness and mishap were approached over 60% and cases of homicide were less than 1%. The closure cases of preliminary investigation were reached over 70% and the most of deaths occurred in fishing vessels (the range of 20 ~ 99 tonnage). The suspension cases of preliminary investigation were reached to 70% of all missing and drowning cases. The results showed that the most of deaths occurred at sea could be prevented by the safety regulations including mandatory report of accidents, marine safety education and training, punishment the people responsible for the accidents. For the unidentified bodies, data should be collected and recorded for the future identification. The crime scene investigators should be trained to ensure the quality of their professional skills regularly.