• Journal of the Korea Institute of Information Security & Cryptology
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• v.29 no.6
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• pp.1243-1257
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• 2019

With the emergence of the IoT environment, various smart devices provide consumers with the convenience and various services. However, as security threats such as invasion of privacy have been reported, the importance of security issues in the IoT environment has emerged, and in particular, the security problem of key management has been discussed, and the PUF has been discussed as a countermeasure. In relation to the key management problem, a protocol using MIPUF has been proposed for the security problem of the group key management system. The system can be applied to lightweight IoT environments and the safety of the PUF ensures the safety of the entire system. However, in some processes, it shows vulnerabilities in terms of safety and efficiency of operation. This paper improves the existing protocol by adding authentication for members, ensuring data independence, reducing unnecessary operations, and increasing the efficiency of database searches. Safety analysis is performed for a specific attack and efficiency analysis results are presented by comparing the computational quantities. Through this, this paper shows that the reliability of data can be improved and our proposed method is lighter than existing protocol.

• Korean Management Science Review
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• v.26 no.2
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• pp.37-59
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• 2009

Electronic brainstorming (EBS) to improve the process and outcomes of group decision making is an artifact of Information Systems legacy. Despite three decades of research with EBS in an effort to become a key resource of organizational performance, its performance when compared to that of nominal is inconclusive because of the recent debate over its usefulness in terms of productivity. Subsequent researchers have directed our attention to the re-examination of cognitive stimulation, which is considered the major benefit in computer-based idea generation, to explain the performance singularity in computer-based groups. While both cognitive and motivational factors that moderate and mediate the group-interaction process remain unexplored, individual differences that are tightly linked to creative behavior have been largely ignored to account for the discrepancy in performance. Since simulations have been widely used in situations where an outcome does not meet the assumptions, the notion of a group simulator and detailed simulation mechanisms are introduced to examine the potential effects of individual differences on the performance of computer-based idea generation groups. In addition, two prior studies that empirically explored cognitive mechanisms with the group simulator are showcased along with six propositions to initiate future research.

• Asian Journal of Business Environment
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• v.1 no.1
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• pp.5-8
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• 2011

This study has been conducted by focusing franchisor's leadership style, franchisee's followership, group-efficacy and their trust in order to achieve positive integration of the franchise system. The key results of empirical examination on the moderating effect of group-efficacy and trust between leadership style proposed by Path-Goal Theory and followership has been found as follows. First, franchisors should be showed their leadership style to fit their mutual business situation. Second, Franchisors and franchisees will be found many ways to increase level of franchisee's group-efficacy. Third, Franchisors will be obtained trust from their own franchisees. These efforts will be given high level of franchisees' trust and group-efficacy. As a result, positive integration of the franchise system will both enhance their competitiveness.

• Journal of Engineering Education Research
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• v.9 no.4
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• pp.5-9
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• 2006

In this research, a case study for cooperative learning practiced in a design class for environmental engineering was presented. Designing a treatment facility for urban diffuse pollution was a main problem given to the participants. Turn-key system for civil works were simulated throughout class works. Twenty five students were grouped into four virtual companies and assigned own position from chairperson to workers. Each group competed throughout establishing design concept regarding order, expense calculation, process distribution, actual calculation. Best design with lowest bidding won the first place. For evaluating class effectiveness, one student from each group were monitored thorough semester. Participants were improved for their understanding about company establishment, turn-key system management, awareness about personal management, and presentation skills. Tension of the class was effectively elevated as well.

• Journal of Industrial Convergence
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• v.7 no.1
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• pp.21-31
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• 2009

Multicast is a network technology for the delivery of information to a group of destinations simultaneously using the most efficient strategy to deliver the messages over each link of the network only once, creating copies only when the links to the multiple destinations split. This thesis designed a group certificate that can authenticate group information safety between cores based on CBT, proposed a multicast security system that can control some security key.

• The Journal of Economics, Marketing and Management
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• v.3 no.2
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• pp.9-20
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• 2015

Could blood type provide a key to wellness and even affect our personality? The theory that blood type is linked to personality (and other mental and physical qualities) is popular mainly in Japan, though it has carried over to Taiwan and South Korea. The present study is the result of a scientific research in which the relationship between two important variables, namely blood group a nd group participation, are determined in the research framework. Based on some collected data from manufacturing firms which are accepted firms in Tehran Stock Exchange, and through cluster sampling a sample was selected. 380 questionnaires were distributed to the personnel of production line, of the firms then the reliability and validity of the questionnaires through independence test and average ratio comparison of the two population were examined, and through Pearson's chi-square formula, the relationship between blood group (independent variable) and group participation (dependent variable) were tested, then through Schuprow coefficient, the prioritization of blood groups over group participation was identified and the following results were obtained: people group participation is affected by their personality features which is derived from their temperament, mood, and characteristics. The study also showed that people blood groups has an effect on their group cooperation, and among blood groups, blood group A has the greatest tendency to group participation and then blood group O, AB, B are prioritized respectively.

• Journal of the Korea Society of Computer and Information
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• v.18 no.11
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• pp.115-124
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• 2013

In this paper, we suggest a secure data dissemination by Lightweight Individual Encryption Multicast scheme over wireless sensor networks using the individual encryption method with Forward Error Correction instead of the group key encryption method. In wireless sensor networks, a sink node disseminates multicast data to the number of sensor nodes to update the up to date software such as network re-programming and here the group key encryption method is the general approach to provide a secure transmission. This group key encryption approach involves re-key management to provide a strong secure content distribution, however it is complicated to provide group key management services in wireless sensor networks due to limited resources of computing, storage, and communication. Although it is possible to control an individual node, the cost problem about individual encryption comes up and the individual encryption method is difficult to apply in multicast data transmission on wireless sensor networks. Therefore we only use 0.16% of individually encrypted packets to securely transmit data with the unicast to every node and the rest 99.84% non-encrypted encoded packets is transmitted with the multicast for network performance.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.21 no.3
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• pp.75-88
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• 2011

Messages need to transmit to the neighbors securely in wireless sensor network, because a sensor node is deployed in hostile area. Thus it is necessary to support secure communication. One of the most important communication part is secure multicast. Especially, group rekeying is a big problem for multicast key management. So, group rekeying must be proceed securely when secrete information is exposed by attacker. Many group rekeying schemes have been studied for ad hoc networks. However, these schemes are Ill1desirable in WSNs. In this paper, we proposed a novel group rekeying scheme in WSNs that it has very powerful security.

• Journal of Haehwa Medicine
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• v.23 no.1
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• pp.21-55
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• 2014

Objectives : This report describes the original references of 154 formulas related to the use of Rhei Rhizoma main blended from Dongeuibogam. Methods : This study analyzes the original references of 154 formulas including Rhei Rhizoma as a key component in Dongeuibogam. Results : There were five types as follows: 1.There is no exact match between 154 formulas in Dongeuibogam and the original formulas in references. 2. Case that could not found the original formula in reference: 22%. 3. Case that the citation is the similar to the original reference: 4%. 4. Case that the citation is not same to expression but contents basically: 73%. 5. Case of addition of content: 1% Conclusions : Most formulas related to the use of Rhei Rhizoma main blended from Dongeuibogam are similar to the contents in the original references. But we can find that Heo Jun, who writes Dongeuibogam, modifies the contents for his intention of editing, idea and situation in Korea.

• Psychiatry investigation
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• v.15 no.11
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• pp.1046-1052
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• 2018

Objective The aims of the present study were to explore the occurrence of childhood trauma and importantly to determine the impacts of childhood trauma on psychosocial features in a Chinese sample of young adults. Methods A survey was carried out in a group of 555 university students by using Childhood Trauma Questionnaire (CTQ), Self-rating Depression Scale (SDS), Self-rating Anxiety Scale (SAS), Dysfunctional Attitudes Questionnaire (DAS), Eysenck Personality Questionnaire (EPQ), and Social Support Rating Scale (SSRS). The moderate-severe cut-off scores for CTQ were used to calculate the prevalence of childhood trauma, and then psychosocial features were compared between individuals with and without childhood trauma. Results A proportion of 18.6% of university students had self-reported childhood trauma exposures. Subjects with childhood trauma reported higher scores of SDS, SAS, DAS, and psychoticism and neuroticism dimensions of EPQ (t=4.311-5.551, p<0.001); while lower scores of SSRS and extraversion dimension of EPQ (t=-4.061- -3.039, p<0.01). Regression analyses further revealed that scores of SAS and DAS were positively (Adjusted B=0.211-0.230, p<0.05), while scores of SSRS were negatively (Adjusted B=-0.273- -0.240, p<0.05) associated with specific CTQ scores. Conclusion Childhood trauma is still a common social and psychological problem. Individuals with childhood trauma show much more depression, anxiety, distorted cognition, personality deficits, and lower levels of social support, which may represent the social and psychological vulnerability for developing psychiatric disorders after childhood trauma experiences.