• Communications of the Korean Mathematical Society
• /
• v.32 no.2
• /
• pp.353-359
• /
• 2017

Starting from a t-norm T, it is possible to construct a class of new t-norms, so-called T-generalized t-norm. The purpose of this paper is to describe some properties of this class of generalized t-norms. An algebraic structure as well as a binary relation among t-norms are also investigated. Some open problems are discussed as well.

• The Journal of the Korea Contents Association
• /
• v.16 no.8
• /
• pp.97-106
• /
• 2016

The results of advanced studies which handled the relationship between social norm and intention to use illegal download don't match exactly. This study determined that the reason why the results of advanced studies are confused is, that moderator variables play important roles. For this reason, this study planned to test for significance of moderators consisting of attitude to copyright law(A) and perceived price importance at time of purchase(B). To achieve this, the present study divide social norm into two norms(subjective norm and group norm) and set up hypotheses on the moderating effects of two variables(A, B) between these two norms and intention to use the illegal download. The results show that all but one hypotheses are accepted. The other moderating effect hypothesis which is consist of subjective norm and attitude toward copyright law is rejected. This means that the effect of group norm on intention to use illegal download is moderated by attitude to copyright law. Also, this result means the effects of group/subjective norm on intention to use illegal download is moderated by the perceived price importance at time of purchase.

• Journal of Acupuncture Research
• /
• v.27 no.5
• /
• pp.51-58
• /
• 2010

Objectives : The purpose of this study is to assess the effect of laser acupuncture at $HT_7$ for reducing mental stress using power spectrum analysis of the heart rate variability. Methods : 36 healthy volunteers(control group: 18, treatment group: 18) participated in this study. After instrumentation and 5-minute rest period, 5-minute metal stress by operation was provided. HRV was recorded before and after the mental stress(1st, 2nd HRV). After 2nd HRV recording, the control group rested for 15 minutes without any treatments. Participants in the treatment group received laser acupuncture to $HT_7$ unilaterally and rested for 15minutes. Points were irradiated for 60seconds, and the intensity was 1.8J(output 20%). And then 3rd HRV was recorded. Results : In simple rest group, LF norm showed a significant change after mental stress. In laser acupuncture group, LF norm, HF norm, LF, HF and LF/HF ratio showed a significant change after mental stress. But there were no significant difference between two groups(ANCOVA test, p>0.05). In laser acupuncture group, LF norm, HF norm, HF and LF/HF ratio showed a significant change after laser acupuncture treatment. And there were significant differences between two groups(p<0.05). Conclusions : This study suggests that laser acupuncture at $HT_7$ can regulate and prevent the alternation of autonomic nervous system due to mental stress.

• The Journal of Information Systems
• /
• v.19 no.3
• /
• pp.209-236
• /
• 2010

Recently, utilization of mobile Internet services is rapidly increasing. To properly accelerate the vitalization of mobile Internet usage, we have to know exactly about the factors affecting potential users' value recognition and intention to use. Technology acceptance model (TAM) is one of the most powerful reference framework for the individual user's adoption of IT innovations. This research borrowed core concept of TAM, and tried to explain users' intention to use mobile Internet by understanding the direct and indirect effects of subjective norm and perceived usefulness. To increase the explanatory power of the model, this paper introduced personal innovativeness as a key moderator variable. The research findings include; i) subjective norm has strong positive influence on perceived usefulness and intention to use, ii) perceived usefulness has positive influence on intention to use, iii) the influence of subject norm is greater than that of perceived usefulness, iv) positive influence of subjective norm on the perceived usefulness and intention to use are significantly stronger in the case of low personal innovativeness sub-group than the case of high personal innovativeness sub-group, and v) high personal innovativeness sub-group have shown strongly positive influence of perceived usefulness on the intention to use while there is no such significant relationship in the case of low personal innovativeness sub-group. Based on these findings, this paper proposed several guidelines to increase the adoption and the usage of mobile Internet; i) word-of-mouth is extremely important, ii) to form a good word-of-mouth, it will be very important to make early adopters and heavy users have positive direct experiences of using mobile Internet.

• Industrial Engineering and Management Systems
• /
• v.13 no.4
• /
• pp.442-448
• /
• 2014

Portfolio optimization in the presence of estimation error can be stabilized by incorporating norm-constraints; this result was shown by DeMiguel et al. (A generalized approach to portfolio optimization: improving performance by constraining portfolio norms, Management Science, 5, 798-812, 2009), who reported empirical performance better than numerous competing approaches. We extend the idea of norm-constraints by introducing a powerful enhancement, grouped selection for portfolio optimization. Here, instead of merely penalizing norms of the assets being selected, we penalize groups, where within a group assets are treated alike, but across groups, the penalization may differ. The idea of groupwise selection is grounded in statistics, but to our knowledge, it is novel in the context of portfolio optimization. Novelty aside, the real benefits of groupwise selection are substantiated by experiments; our results show that groupwise asset selection leads to strategies with lower variance, higher Sharpe ratios, and even higher expected returns than the ordinary norm-constrained formulations.

• Journal of Acupuncture Research
• /
• v.25 no.1
• /
• pp.15-23
• /
• 2008

Objectives : The aim of our study was to demonstrate the clinical application of a diagnosis relating the 7-zone-diagnostic system and heart rate variability. Materials and Methods : Subjects were divided into two groups according to the factor AA form of the 7-zone-diagnostic system(VEGA-DFM722, VEGA, Germany). Subjects in group A showed a factor-AA red bar graph in which zone 2 was higher than the normal range, and zone 6 was lower than the normal range. Subjects in group B showed a factor-AA red bar graph in which zone 2 was lower than the normal range, and zone 6 was higher than the normal range. We investigated how to differentiate the index of heart-rate variability(HRV, LX-3202, LAXTHA, Korea) for each group. We did independent sample t-tests and evaluated the results of the HRV at the 5% significance level using SPSS 10.0 for Windows. Results : The differences of the MeanRR, MeanHRV, SDNN, complexity, HRV-index, RMSSD, SDSD, and pNN50 values between the groups was not significant. The differences of the Ln(TP), Ln(VLF), Ln(HF), LF/(LF+HF), LF/HF, norm LF, and norm HF values between the groups was also not significant. The differences were not significant, but generally the values of SDNN, complexity, RMSSD, SDSD, Ln(VLF), Ln(HF) and norm LF for group B were higher than those for group A, and the values of pNN50 and norm HF for group B were lower than those for group A. Conclusions : This study suggests that differences in the HRV values between the groups was not significant, but group B has a tendency to be healthier than group A because of stress. Accordingly, further study will be required.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.34 no.1
• /
• pp.30-36
• /
• 2020

This study aimed to investigate heart rate variability (HRV) characteristics of cold pattern with repeated measurement data. Participants were taken from a Daejeon University cohort study from 2015 to 2018. Forty-seven of the participants studied displayed cold pattern while 23 showed signs of non-cold pattern. HRV was measured in supine position for 5 minutes at each year, and an 8-item cold pattern questionnaire was used for the diagnosis of cold pattern. SDNN (standard deviation of the NN intervals) and RMSSD (the square root of the mean squared differences of successive NN intervals) were used as time domain analysis, and TP (total power), VLF (power in very low frequency range), LF (power in low frequency range), HF (power in high frequency range), LF norm (LF power in normalized units), HF norm (HF power in normalized units) and LF/HF were used as frequency domain analysis. In the Mann-Whitney U test, LF norm, HF norm, and LF/HF showed differences between the cold pattern group and non-cold pattern group at every measurement, and in the independent t-test, the differences were also observed at three points except for the baseline (2015). In the repeated measures ANOVA, the interaction effects were not observed in all HRV parameters, but the time period effects were observed in SDNN, RMSSD, TP, VLF, LF and HF. There were significant differences between those two groups in LF norm, HF norm and LF/HF. This study suggests that LF norm, HF norm and LF/HF might be a useful indicator of cold pattern properties.

• International Commerce and Information Review
• /
• v.9 no.4
• /
• pp.265-288
• /
• 2007

This study analyzed which conflict management norm was preferred according to unique cultural difference of nation and such conflict management norm influences on conflict management type in solving real conflict when conflict in organization occurs and such conflict norm had a preference and influence on conflict management type in solving real conflict through such conflict management norm. As the result, first, Korean managers showed still high attitude on group interest and aimed to negotiation. But they highly depended on control. Canada managers showed discussion norm of individual interest and performed conflict management laying stress on unity and negotiation. second, as for conflict management of negotiation, both Canada and Korea performed it on the based of his or her interest discussion and as for plural agenda unity positively influenced to unity conflict management in Korea but in Canada, attitude for the future negatively influenced.

• Asia Marketing Journal
• /
• v.22 no.1
• /
• pp.41-60
• /
• 2020

The goal of the study is to understand the role of social norm in purchase decisions where demand is revealed in the form of multiple-discreteness. Consumers are socially engaged in various activities through the expectation from others in their community. Actions or decisions are likely to reflect this influence. This implicit or explicit social norm is revealed as the rules, regulations, and standards that are understood, shared, endorsed, and expected by group members. When consumers' decisions are in distance from the norm, they come to face discomfort such as shame, guilt, embarrassment, and anxiety. These pressure act as a constraint as opposed to utility in their decision making. In this study, the effect of social norms on consumer demand is captured via multiple constraint model where constraints are not only from budget equation but also from psychological burden induced by the deviation from the norm. The posterior distributions of model parameters were estimated via conjoint study allowing for heterogeneity via hierarchical Bayesian framework. Individual characteristics such as age, gender and work experience are also used as covariates for capturing the observed heterogeneity. The empirical results show the role of social norm as constraint in consumers' utility maximization. The proposed model accounting for social constraint outperforms the standard budget constraint-only model in terms of model fit. It is found that people with longer job experience tend to be more robust and resistant to the deviation from the norm. Incorporating social norm into the utility model allows for another means to disentangle the reason for no-purchase as 'not preferred' and 'not able to buy'.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.12
• /
• pp.212-223
• /
• 2019

The purpose of this study was to investigate how attitude, subjective norm, and perceived behavioral control affect nurses' pressure ulcer (PU) prevention behavior among general hospital nurses based on the theory of planned behavior. A total of 111 nurses in four general hospitals in Korea participated in this study and replied to a survey on attitude, subjective norm, perceived behavioral control, and behavior regarding PU prevention. Data were analyzed with multiple regressions by all participants, education level, working department, and hospital size group. In all participants, the more positive attitude and the higher subjective norm, the more PU prevention behavior. However, in the group of 'more than bachelor degree' and 'tertiary hospital', the more clinical experience, the more behavior. In the group of 'surgical ward & intensive care unit', the higher attitude, the more behavior. In the group of 'more than bachelor degree', the higher subjective norm, the more behavior. Therefore, personalized and tailored intervention for nurses may be provided depending on nurses' education level, work department, and hospital size to enhance PU prevention behavior by means of improving nurses' attitude, subjective norm toward PU prevention.