• Korean Journal of Forensic Psychology
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• v.12 no.1
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• pp.53-73
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• 2021

This study is an experimental study comparing the psycho-physiological response differences of subjects according to the rapport building in polygraph tests. We randomly assigned 84 adults into a 2(veracity: Truth vs. Lie) x 2(rapport; Rapport building vs. Non-rapport building) between-subject design and measured ESS total scores as psycho-physiological responses. In order to manipulate the veracity conditions, participants in the truthful condition were told to tell their actual scores on several simple tasks but those in the lie condition were asked to tell higher scores than their actual scores. Afterwards all participants were polygraph tested in the order of pre-interview and main examination. The rapport conditions were manipulated by structured pre-interview scripts. As a result, there were significant differences in the examinee's total ESS scores depending on the veracity and rapport conditions. For truth-tellers, the ESS total scores were greater in the positive(+) direction in the rapport building condition than in the non-rapport building condition, indicating a prominent true response in the former condition. For liars, however, the ESS total scores were not significantly greater in the negative(-) direction in the rapport building condition than in the non-rapport building condition. Based on this study's results, we discussed the importance of rapport building in the pre-interview phase of a polygraph test and the need to operationalize verbal and non-verbal rapport building techniques.

• Korean Journal of Cognitive Science
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• v.35 no.1
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• pp.49-95
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• 2024

Polygraph examination, statement validity analysis and P300-based concealed information test are major three examination tools, which are use to determine a person's truthfulness and credibility in criminal procedure. Although polygraph examination is most common in criminal procedure, but it has little admissibility of evidence due to the weakness of scientific basis. In 1990s to support the weakness of scientific basis about polygraph, Farwell and Donchin proposed the P300-based concealed information test technique. The P300-based concealed information test has two strong points. First, the P300-based concealed information test is easy to conduct with polygraph. Second, the P300-based concealed information test has plentiful scientific basis. Nevertheless, the utilization of P300-based concealed information test is infrequent, because of the quantity of probe stimulus. The probe stimulus contains closed information that is relevant to the crime or other investigated situation. In tradition P300-based concealed information test protocol, three or more probe stimuli are necessarily needed. But it is hard to acquire three or more probe stimuli, because most of the crime relevant information is opened in investigative situation. In addition, P300-based concealed information test uses oddball paradigm, and oddball paradigm makes imbalance between the number of probe and irrelevant stimulus. Thus, there is a possibility that the unbalanced number of probe and irrelevant stimulus caused systematic underestimation of P300 amplitude of irrelevant stimuli. To overcome the these two limitation of P300-based concealed information test, one-probe P300-based concealed information test protocol is explored with various machine learning algorithms. According to this study, parameters of the modified one-probe protocol are as follows. In the condition of female and male face stimuli, the duration of stimuli are encouraged 400ms, the repetition of stimuli are encouraged 60 times, the analysis method of P300 amplitude is encouraged peak to peak method, the cut-off of guilty condition is encouraged 90% and the cut-off of innocent condition is encouraged 30%. In the condition of two-syllable word stimulus, the duration of stimulus is encouraged 300ms, the repetition of stimulus is encouraged 60 times, the analysis method of P300 amplitude is encouraged peak to peak method, the cut-off of guilty condition is encouraged 90% and the cut-off of innocent condition is encouraged 30%. It was also conformed that the logistic regression (LR), linear discriminant analysis (LDA), K Neighbors (KNN) algorithms were probable methods for analysis of P300 amplitude. The one-probe P300-based concealed information test with machine learning protocol is helpful to increase utilization of P300-based concealed information test, and supports to determine a person's truthfulness and credibility with the polygraph examination in criminal procedure.

• Convergence Security Journal
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• v.15 no.3_1
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• pp.41-51
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• 2015

Human have more complicate and skilled ability for lying even cheat ourself. It is not easy to cheat unconscious things like sweat, eyes, or voice, but if some one cheat own self, he can cheat every of that. Lie is one of the way to spread our gene and our instinct make a lie. Every living organism even bacteria or virus use similar trick to survive. In human body, there are more complicate and profound mechanism for lying like breathe, sweat, eyes, face or voice. We can control some of that and make a fake, but it can't be perfect. Human also called 'Homo Fallax' cause we have a language and skill to lie with it. In present, we can detect lie with polygraph, but it has few weakness. So we try to use Vibraimage technology for resolve it. In this paper, we describe how to use Vibraimage for lie detection and the research history.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.184-192
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• 2017

This study was a pilot test of serious educational game content(named Roly Poly 160) designed to enhance self-care by elderly diabetics. Roly Poly 160 was developed in eight steps (literature review, demand survey and consultation, extraction of serious content using games, development of Roly Poly 160, pretest for users, workshop for health care workers, final completion of Roly Poly 160 and user satisfaction survey of Roly Poly 160). Roly Poly 160 is intuitively structured in three modules (self-management, card games, and quiz games) that can be self-managed by the elderly and is designed based on six principles. First, we constructed an intuitive interface considering the age of users. Second, the menu was selected as the main menu for Koreans and calorie learning was made at the same time. Third, the calories and nutrients (carbohydrate, fat, protein, calcium, sodium) of selected foods are analyzed, and all test data recorded in the questionnaire chart are graphically displayed by year, month and week so that the change trends can be grasped at a glance. Fourth, necessary data were saved and output and used as educational data. Fifth, user data are made compatible and aggregated and up to 100 million members can be registered. Sixth, it is designed to be developed as a mobile app if necessary. Using Roly Poly 160, 119 diabetic patients were diagnosed with diabetes, and the satisfaction score was 4.26 out of 5. These findings indicate that Roly Poly 160 is appropriate as a diabetes self-care tool and suggests that there is a possibility to use it as a program to educate people about diabetes in public health centers, hospitals and clinics.