• Journal of Internet Computing and Services
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• v.23 no.5
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• pp.69-78
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• 2022

As the use of Internet of Things (IoT) devices has expanded, digital forensics coverage of the National Police Agency has expanded to smart home areas. Accordingly, most of the existing studies conducted to acquire smart home platform data were mainly conducted to analyze local data of mobile devices and analyze network perspectives. However, meaningful data for evidence analysis is mainly stored on cloud storage on smart home platforms. Therefore, in this paper, we study how to acquire stored in the cloud in a Hey Home Air environment by extracting accessToken of user accounts through a cookie database of browsers such as Microsoft Edge, Google Chrome, Mozilia Firefox, and Opera, which are recorded on a PC when users use the Hey Home app-based "Hey Home Square" service. In this paper, the it was configured with smart temperature and humidity sensors, smart door sensors, and smart motion sensors, and artifacts such as temperature and humidity data by date and place, device list used, and motion detection records were collected. Information such as temperature and humidity at the time of the incident can be seen from the results of the artifact analysis and can be used in the forensic investigation process. In addition, the cloud data acquisition method using OpenAPI proposed in this paper excludes the possibility of modulation during the data collection process and uses the API method, so it follows the principle of integrity and reproducibility, which are the principles of digital forensics.

• Korean Journal of Materials Research
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• v.32 no.4
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• pp.200-209
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• 2022

In this study, defects generated in the YSZ coating layer of the IN738LC turbine blade are investigated using an optical microscope and SEM/EDS. The blade YSZ coating layer is composed of a Y-Zr component top coat layer and a Co component bond coat layer. A large amount of Cr/Ni component that diffused from the base is also measured in the bond coat. The blade hot corrosion is concentrated on the surface of the concave part, accompanied by separation of the coating layer due to the concentration of combustion gas collisions here. In the top coating layer of the blade, cracks occur in the vertical and horizontal directions, along with pits in the top coating layer. Combustion gas components such as Na and S are contained inside the pits and cracks, so it is considered that the pits/cracks are caused by the corrosion of the combustion gases. Also, a thermally grown oxide (TGO) layer of several ㎛ thick composed of Al oxide is observed between the top coat and the bond coat, and a similar inner TGO with a thickness of several ㎛ is also observed between the bond coat and the matrix. A PFZ (precipitate free zone) deficient in γ' (Ni₃Al) forms as a band around the TGO, in which the Al component is integrated. Although TGO can resist high temperature corrosion of the top coat, it should also be considered that if its shape is irregular and contains pore defects, it may degrade the blade high temperature creep properties. Compositional and microstructural analysis results for high-temperature corrosion and TGO defects in the blade coating layer used at high temperatures are expected to be applied to sound YSZ coating and blade design technology.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.239-248
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• 2022

Forensic entomology is a study that purposes at field reconstruction through insects attracted to carcasses, and has been mainly studied using carcasses such as a pig and chicken. Therefore, this study was conducted to find out if there is a singularity by using the carcass of water deer with different conditions and shapes of the hair quality and to find out the appearance of a necrophagous insect. The water deer carcass was received from the Jeollanam-do Wildlife Rescue Management Center and research was conducted. From May 19 2021 to July 2 2021, the decay progress of the carcass was observed for about 6 weeks. A total of 51 species of 21 families in 4 orders of insects were collected. Even after the carcass completely decays, even at the stage where the activity of other insects is not observed, insects such as Dermestidae and Tenebrionidae are collected from the hairs and leather of water deer carcass until the last. It was confirmed that insects of the order Coleoptera other than Diptera can be used as forensic entomological data related to the decay of carcasses with fur.

• Korean Journal of Forensic Psychology
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• v.12 no.1
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• pp.1-13
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• 2021

This study analyzed the use of expert reports in the investigations and trials of cases of sexual violence against people with intellectual disabilities. A total of 670 alleged sexual assault cases against victims with intellectual disabilities were analyzed. Results showed that 97.5% of the cases included at least one expert report. In most cases(91%), the expert reports of statement validity assessment were included. Additionally, doctor's note (41.1%) from obstetricians and Psychiatrists, intermediary reports(36%), and expert witnesses(psychologists') reports (9.5%) were included. In 80 cases (44.4%) of the 180 cases in which a victim' statement credibility was in question during the trial, judges cited the expert's reports of statement validity assessment as the basis for the judgment on the reliability of the victims' accusation. The frequency of citing the report was higher when the victim was under the age of 13, or when the defendant was found guilty. Regrading the report content, the evaluations of criteria-based content analysis(CBCA) was most frequently cited, while the victim's psychological status, cognitive limitation, as well as possibile contamination of victim's account, were also mentioned in the ruling statements. Results showed agreement between experts' statement validity assessments and judges' determinations in 79 cases out of the 80 cases Finally, this study discussed ways to utilize expert options.

• Korean Journal of Forensic Psychology
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• v.12 no.2
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• pp.121-149
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• 2021

Statement Validity Analysis (SVA) is utilized in criminal investigations and the court to assess the credibility of given statements. During this procedure, the criteria for Criteria-Based Content Analysis (CBCA) are used to evaluate whether statements include the characteristics reflecting actual experiences about the event in question. Various studies had been conducted on the efficacy (classification rates) of CBCA criteria, yet the consistency of the findings was not investigated. In the current study, a meta-analysis was conducted with Korean CBCA studies reported from 2004 to 2020 (a total of fourteen studies). As a result, the total score of CBCA was found to successfully discriminate truth and fabrication. A significant positive (+) effect size was found with four criteria (3, 4, 10, and 12), all of which are classified as cognitive criteria. However, contrary to the underlying assumption for CBCA, criterion 18, classified as one of the motivational criteria, showed a significant negative (-) effect size. Meanwhile, moderator analyses were possible for eleven criteria (2~9, 12, 13, 15) and the results showed the significant effects of potential moderator variables such as the gender and status of the participants, study types and designs, number of raters, and publication status. The current results suggests that more careful attention is required to each criterion-especially the cognitive criteria-rather than the total CBCA score as well as the possible moderator effects in order to assess truthfulness of the statements. The implication, limitations, and suggestions for future studies were discussed.

• Korean Journal of Forensic Psychology
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• v.11 no.1
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• pp.89-115
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• 2020

Traditional deception detection methods had examined the difference of one's autonomic physiological responses through asking crime-related and crime-unrelated questions. There has been a continuing controversy regarding the accuracy and validity of the test, and thus, many researchers were motivated to explore and develop alternative efficient methods of detection in which one of them is known as P300-based Complex Trial Protocol (CTP). The P300-based CTP detects deception through comparing the P300 amplitudes between probe and irrelevant stimuli and is known as a counterstrategy of countermeasures. However, many previous studies have used countermeasures created from Rosenfeld et al.'s work (2008). The present study initially conducted a survey asking open-ended questions about the countermeasure use to acquire participant-oriented countermeasures for the main experiment. Then, the study aimed to evaluate whether the CTP can accurately detect deception even in the use of survey-based countermeasures. We firstly selected a set of participant-oriented countermeasures through survey questions. Then, a total of 50 participants were divided into three groups (innocent, guilty, and countermeasures) and performed the CTP. Those assigned to the countermeasures group covertly performed mental countermeasures during the CTP. The results of P300 amplitude analysis revealed that the guilty group's P300 amplitude of probe stimuli was significantly larger than that of irrelevant stimuli. Countermeasures group also had a significantly larger P300 amplitude for probe stimuli compared to irrelevant stimuli, even in the use of countermeasures. The results of bootstrapped amplitude difference (BAD) showed a detection accuracy rate of 81.25%, 82.35%, 82.35% for the innocent, guilty, and countermeasures groups, respectively. These findings demonstrate that the CTP can obtain a high detection rate in participant-oriented countermeasures and suggest the potential use of the CTP in the field.

• Industry Promotion Research
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• v.8 no.2
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• pp.157-164
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• 2023

Since there are no related laws and regulations in the Korean private investigation industry, anyone can freely operate it if they report the business to the tax office. The reality is that companies hire PI to investigate rival companies and employees for specific reasons, as they generally rely on individual requests. The Korean PI industry is divided into two parts. The first are retired police officers and investigators who have experience in criminal investigation. The second are private citizen who can conduct investigation service activities runs a PI agency after everyone has registered with the tax office. It is no exaggeration to say that the current legal conflicts and legal problems that arise in the PI service cannot be ruled out because civilians are relatively less knowledgeable than PIs and legal experts. Therefore, in order for PI industry to operate stably in Korea, we will first study the concept and type of PI industry, comparative analysis of past PI laws, current status and reality of PI industry, and study the current status and references.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.33 no.3
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• pp.511-525
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• 2023

As awareness of personal data protection increases, various Full Disk Encryption (FDE)-based applications are being developed that real-time encryption or use virtual drive volumes to protect data on user's PC. FDE-based applications encrypt and protect the volume containing user's data. However, as disk encryption technology advances, some users are abusing FDE-based applications to encrypt evidence associated with criminal activities, which makes difficulties in digital forensic investigations. Thus, it is necessary to analyze the encryption process used in FDE-based applications and decrypt the encrypted data. In this paper, we analyze Cryptomator and Norton Ghost, which provide volume encryption and backup functions. We analyze the encrypted data structure and encryption process to classify the main data of each application and identify the encryption algorithm used for data decryption. The encryption algorithms of these applications are recently emergin gor customized encryption algorithms which are analyzed to decrypt data. User password is essential to generate a data encryption key used for decryption, and a password acquisition method is suggested using the function of each application. This supplemented the limitations of password investigation, and identifies user data by decrypting encrypted data based on the acquired password.

• 한국노년학
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• v.29 no.2
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• pp.563-578
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• 2009

Public pension system of western welfare states has been maintained by transfers of public resources between working-age population and old-age population. But population aging cause the problem of fiscal burden on pension financing, so cutback on public spending for the elderly has been on the issue at public agenda. The argument on public spending for the elderly is more aggressively proceeded in the United States than any other welfare states. The argument is concerned with the problems of generation and is going under the rhetoric name of 'Generational Equity' which contends unequal distribution of social resources such as federal budget within generations. This article analyzes the background of 'Generational Equity' perspective and the reason why that argument is actively going forward in the U. S. and political-economy context of that argument. Generational Equity perspective contends that the elderly are getting more benefits and high spending on the elderly has contributing to the rising poverty rate of children. But there are lots of objection to this perspective on the ground that the perspective has weak positive evidences. The reason that 'Generational Equity' perspective has the power only in the U. S. but other welfare states is mainly due to that pluralistic political regime and selective welfare system. This research presents that political-economy meaning of 'Generational Equity' perspective is related to the political regime and welfare system of the society itself. And this research has the implication that our society having a selective welfare system would take a risk of encountering 'Generational Equity' social debate in the near future.

• Korean Journal of Culture and Social Issue
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• v.19 no.3
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• pp.343-365
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• 2013

This study examined the effects of various individual differences on children's memory of a stressful experience. The participants for the current study were children (N=85) aged 4-9 years those who experienced a naturally occurring stressful experience from a dental procedure. There was overall negative relation between the level of stress and children's memory performance. However, more interestingly, the results of this study provided some further evidence that several cognitive (i.e., receptive language ability and working memory capacity) and emotional (i.e., children's general anxiety condition, children's self-report of pain and anxiety about the event) individual difference factors were associated with variations in children's remembering across ages. The results suggest that the relation between stress and children's memory might be impacted in part by children's various individual characteristics. Furthermore, the findings are discussed in the applied context that based on the results clinical and legal professionals can tailor interviews to best meet children's needs and capabilities, and create developmentally and individually sensitive guidelines for interviewing children in the legal system.