• Information Systems Review
• /
• v.5 no.2
• /
• pp.71-90
• /
• 2003

Virtual communities have been suggested to play important roles such as attracting customers, building customer loyalty, and leading to commercial transactions. Little research in marketing has focused on virtual communities in spite of its importance indicated by many practitioners and conceptual studies. More specifically, little research has empirically examined factors of customer participation and its consequences. This research investigate if customers' participation motives in virtual communities affect their sense of community and if sense of community affects customers' loyalty towards and purchase intentions from the website offering the community service. One hundred ninety six questionnaires were collected from individuals who have participated in and have been involved in online activities in various virtual communities. Major results of this research can be summarized as follows. First, participation motives employed significantly affected customers' sense of community and more specifically, perceived ease of use and perceived playfulness had a large influence on the customers' sense of community. Second, customers' sense of community positively affected their loyalty toward the community and more specifically, membership and emotional connection had a large influence on loyalty. Third, customers' sense of community did not affect directly their purchase intentions. Fourth, customers' loyalty toward virtual communities had a significant, positive, although marginal, influence on their purchase intentions.

• Journal of the Korean earth science society
• /
• v.38 no.5
• /
• pp.333-344
• /
• 2017

We present the environmental dependence of the luminosity-size relation of galaxies in the local universe (z < 0.01) along with their dependence on galaxy morphology represented by five broad types (E, dEs, S0, Sp, and Irr). The environmental parameters we consider are the local background density and the group/cluster membership together with the clustercenteric distance for the Virgo cluster galaxies. We derive the regression coefficient (${\beta}$), i.e., the slope of the line representing the least-squares fitting to the data and the Pearson correlation coefficient (c.c.) representing the goodness of the least-squares fit along with the confidence interval from bootstrap resampling. We find no significant dependence of the luminosity-size relation on galaxy morphology. However, there is a weak dependence of the luminosity-size relations on the environment of galaxies, in the sense that galaxies in the low density environment have shallower slopes than galaxies in the high density regions except for elliptical galaxies that show an opposite trend.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.9 no.6
• /
• pp.577-582
• /
• 1999

Using a sole input variable simplifies the design process for the fuzzy logic controller(FLC). This is called single-input fuzzy logic controller(SFLC). However it is still deficient in the capability of adapting to the varying operating conditions. We here design a single-input adaptive fuzzy logic controller(AFLC) using a switching function of the sliding mode control. The AFLC can directly incorporate linguistic fuzzy control rules into the controller. Hence some parameters of the membership functions characterizing the linguistic terms of the fuzzy rules can be adjusted by an adaptive law. In the proposed AFLC center values of fuzzy sets are directly adjusted by a fuzzy logic system. We prove that 1) its closed-loop system is globally stable in the sense that all signals involved are bounded and 2)its tracking error converges to zero asymptotically. We perform computer simulation using a nonlinear plant.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• v.1 no.1
• /
• pp.44-49
• /
• 2001

For minimum phase systems, the conventional fuzzy logic controllers (FLCs) use the error and the change-of-error as fuzzy input variables. Then the control rule table is a skew symmetric type, that is, it has UNLP (Upper Negative and Lower Positive) or UPLN property. This property allowed to design a single-input FLC (SFLC) that has many advantages. But its control parameters are not automatically adjusted to the situation of the controlled plant. That is, the adaptability is still deficient. We here design a single-input direct adaptive FLC (SDAFLC). In the AFLC, some parameters of the membership functions characterizing the linguistic terms of the fuzzy rules are adjusted by an adaptive law. The SDAFLC is designed by a stable error dynamics. We prove that its closed-loop system is globally stable in the sense that all signals involved are bounded and its tracking error converges to zero asymptotically. We perform computer simulations using a nonlinear plant and compare the control performance between the SFLC and the SDAFLC.

• Proceedings of the KIEE Conference
• /
• 1995.11a
• /
• pp.210-212
• /
• 1995

Its is proposed that a stable adaptive control system composed of a fuzzy and a compensating controller, is designed to control nonlinear systems. In fuzzy and proposed compensating controller, parameters of membership functions characterizing the linguistic terms change according to some adaptive law. The adaptive law are based on the Lyapunov systhesis approach. the closed-loop system using the adaptive control structure proposed in this paper is globally stable in the sense that the Lyapunov function decreases as time goes. the following simulation shows the results.

• Proceedings of the KIEE Conference
• /
• 1994.11a
• /
• pp.370-372
• /
• 1994

In this paper, a stable adaptive composite control system consisting of a PID and a fuzzy controllers is designed to control nonlinear systems. In the fuzzy controller, parameters of membership functions characterizing the linguistic terms change according to some adaptive law. Also, parameters of PID controller change according to some adaptive law. These adaptive laws are based on the Lyapunov synthesis approach. Then, it is proved that the closed-loop system using such an adaptive composite control system is globally stable in the sense that all signals involved are bounded and the tracking error converges to zero. We apply this adaptive composite control system to control a nonlinear system.

• Journal of the Korean Society of Safety
• /
• v.12 no.1
• /
• pp.122-128
• /
• 1997

A new approach, called "two-phase approach", has been proposed In this study. Using this approach to solve MONLP(multiobjective nonlinear programming problem), the solution process is divied into two phase. In the first phase, the min-operator is used to aggregate the membership degree of fuzzy goals and constraints. In the second phase, the $\gamma$-operator is used to test and find an efficient solution in the sense of nondominated. It has been shown that no matter what the solution of the problem is unique or not, an efficient solution can be always obtained at the second phase. The proposed approach can be applied to industrial safety problem with multiobjective problems. On the basis of proposed approach, an illustrative numerical example is presented.presented.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.40 no.12
• /
• pp.1262-1268
• /
• 1991

The electric furnace which has time delay and time varying characteristics cannot be controlled easily. In this paper, a fuzzy controller for a electric furnace is implemented using one chip processor 8751 and IBM PC. The fuzzy controller is implemented in the PC. The One chip processor 8751 can sense the furnace internal temperature and pass it to IBM PC and generate the driving signal for SSR. The membership function of the fuzzy controller is determined by Least Square method. from the experiments, we can show that the fuzzy controller can improve robustness to the load variation. And the settling time is reduce 4500 (sec) to 2500 (sec).

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.4
• /
• pp.2151-2153
• /
• 2013

The history of the APOCP/APJCP goes back to 1999 when a number of interested scientists joined together to form the organization and to launch a new journal to support cancer prevention research in the Asian-Pacific area. Since the initial Founding Conference, some six General Assemblies (GAs) and ten Regional Conferences (RCs) and Special Study Sessions have been organized. Already the decisions have been made for two further GAs and at least three RCs. As of the April issue of 2013, a total of nearly 3,700 papers have already been published in regular issues of the APJCP or special supplements. With support of the Korean National Cancer Center, housing the Chief Editorial Office, the journal is now including approximately 100 papers a month. Although it experienced a set-back by reduction in the Impact Factor (IF) from 1.29 in 2010 to 0.67 in 2011, there are good grounds to expect an improvement in 2012. However, the future of the APOCP/APJCP will continue to depend on its membership, making continuous efforts to attend our conferences and submit good quality manuscripts. It is particularly important to cite papers in the APJCP wherever possible, if the wish is for an IF commensurate with our long term aims. In that sense it is up to all authors, since the journal will continue to have a very positive ploicy towards accepting papers from all countries within the Asian-Pacific, with continue to varied levels of resources. The editorial team looks forward to your considered support. The APOCP also hopes to see you in person at future meeetings, so that you have a more active voice in deciding the best way forward in our cooperative enterprise.

• Journal of Christian Education in Korea
• /
• v.67
• /
• pp.117-156
• /
• 2021

This study was conducted in order to investigate the effect of interaction bewteen a Sense of Community and Marital Intimacy effect on learning participation motive in the church family ministry program. In this study, data from 607 people(male: 302, female: 305) nationwide churches and institutes participating in church family ministry program were collected as analysis targets. The produced results from this study are: First, Emotional connection, one of the Marital Intimacy, has meaningful effect (t=6.087, p<.001) on Continuous motivation, one of the learning participation motive. Second, Membership, one of the Sense of Community, has meaningful effect (t=3.343, p<.001) on Intrinsic motivation, one of the learning participation motive. Third, Influence, one of the Marital Intimacy, has meaningful effect (t=5.358, p<.001) on Extrinsic motivation, one of the learning participation motive.