• Journal of Korea Society of Digital Industry and Information Management
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• v.12 no.4
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• pp.163-169
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• 2016

This study is to analyze factors affecting a growth of online community with perspectives of social network. Particularly this study tries to explore structural phenomenon built by interactions between users in a certain of free board belonging to the online community, in which focuses on one's writing a comments responding on those of others. With using SNA(Social Network Analysis), the social network data calculated from users' interaction shown as their comments were collected to draw out each individual's centrality value representing the structure of the online community and also we estimated duration time and the number of each comments as a proxy variable representing growth of the online community. And then cause-and-effect relationship between individual's centrality value and the duration time and the number of each comment were analyzed. As a result of the analysis, Core-Periphery, Centralization and Reciprocity have significant effects on the duration time and the number of each comment, therefore those significant values representing online structure will give an implication to manage, to promote the online community, to forecast its evolution path and to build critical policies.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2008.10b
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• pp.479-491
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• 2008

A "task network" is a type of social network that consists of experts who exchange professional help and advice regarding executing tasks. In this study, we investigate the task network used within the IS department of a national bank in Korea. We identify how this network moderates the influence of computer-mediated communication (CMC) technology on an individual s task performance. Size, density, and centrality were measured as the characteristics of a personal task networks. Size equates to the total number of colleagues who work with a specific member for a certain project. Density is the ratio of the number of actual relationships to the total number of available relationships. Centrality defines whether an individual s position is in the exact center of whole network, and is measured by betweenness centrality, meaning the position one member holds between others in a network. Our findings conclude that the conditions - the larger the size of the task network, the smaller its density and the higher its level of centrality - lead to more benefits of using CMC media. Further, this positive effect of CMC is more noticeable when it provides synchronicity.

• Wind and Structures
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• v.25 no.3
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• pp.301-328
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• 2017

Multivariate fluctuating pressures acting on a 2:1 rectangular section (2-D) with dimensions of 9 cm by 4.5 cm has been studied using wind tunnel experiments under uniform and smooth flow condition for various angles of wind incidence. Based on the variation of mean pressure coefficient distributions along the circumference of the rectangular section with angle of wind incidence, and with the aid of skin friction coefficients, three distinct flow regimes with two transition regimes have been identified. Further, variations of mean drag and lift coefficients, Strouhal number with angles of wind incidence have been studied. The applicability of Universal Strouhal number based on vortex street similarity of wakes in bluff bodies to the 2:1 rectangular section has been studied for different angles of wind incidence. The spatio-temporal correlation features of the measured pressure data have been studied using Proper Orthogonal Decomposition (POD) technique. The contribution of individual POD modes to the aerodynamic force components, viz, drag and lift, have been studied. It has been demonstrated that individual POD modes can be associated to different physical phenomena, which contribute to the overall aerodynamic forces.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.6
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• pp.15-22
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• 2018

The purpose of this study was to suggest specific evaluation data for heating and DHW energy consumption characteristics through analyzing energy consumption measurement data of gas boiler in Apartment Buildings with individual heating systems. To do this, it was measured both gas flow and electricity for heating and DHW respectively, and then it was analyzed not only characteristics according to energy sources; gas and electricity, but also the effect of various factors on heating and DHW energy consumption. The result of this study were as follows. It was developed the electric energy estimation model of a gas boiler through analysis on patterns by energy sources. And the effective factors for heating and DHW energy consumption were demonstrated as follows: the area for exclusive use, the number of auxiliary heating equipments, the number of occupants, and the number of sanitary fixtures.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.11
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• pp.1529-1534
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• 2005

Individual-breed assignments were implemented in six swine populations using twenty six microsatellites recommended by the Food and Agriculture Organization and the International Society for Animal Genetics (FAO-ISAG). Most microsatellites exhibited high polymorphisms as shown by the number of alleles and the polymorphism information content. The assignment accuracy per locus obtained by using the Bayesian method ranged from 33.33% (CGA) to 68.47% (S0068), and the accumulated assignment accuracy of the top ten loci combination added up to 96.40%. The assignment power of microsatellites based on the Bayesian method had positive correlations with the number of alleles and the gene differential coefficient ($G_{st}$) per locus, while it has no relationship to genetic heterozygosity, polymorphism information content per locus and the exclusion probabilities under case II and case III. The percentage of corrected assignment was highest for the Bayesian method, followed by the gene frequency and distancebased methods. The assignment efficiency of microsatellites rose with increase in the number of loci used, and it can reach 98% when using a ten-locus combination. This indicated that such a set of ten microsatellites is sufficient for breed verification purposes.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.5B
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• pp.365-377
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• 2006

We define the incomplete medium sharing system as a multi-channel shared medium communication system where any types of constraints are imposed to the set of channels that may be allocated to any transmitter-receiver node pair. A set of distributed MAC schemes are proposed, all of which are based on the CSMA/CA scheme employed in IEEE 802. 11 WLAN standards. Distributed MAC schemes are proposed in three different forms, which can be differentiated by the number and the location of back-off timers; that is, (1) one timer for all queues destined for different receiver nodes, (2) multiple timers at individual transmission queues, (3) multiple timers for individual channels. Through an extensive set of computer simulations, the performances of the proposed MAC schemes show that the MAC scheme with timers at individual transmission queues outperform the others in terms of throughput and delay for most cases considered. The complexity of the proposed schemes is also compared, and the first scheme obviously turned out to be the simplest, and the complexity of the second and third schemes depends on the number of receiver nodes and the number of channels, respectively.

• Journal of Technologic Dentistry
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• v.20 no.1
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• pp.61-89
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• 1998

Having taken as cause of dental technicians separation from their service a variety of individual idiosyncrasies, function-related factors, external environment factors, functional satisfaction, organizational commitment, and intention to remain, the present study conducted a mail questionnaire poll and interviews on those dental technicians who are mow in the service with private dental technical workshops and dental technical workshops in general hospitals and private dental clinics. The resultant findings from analysis of the repondent's general characteristics of cause of separation form service were revealed, as follows : 1) It was shown that the higher the academic career, the considerably higher cause of position commitment among causes of individual idio-syncrasies, reflecting a statistically significant result(P<0.05) 2) The less the number of working hours as viewed from the average number of working hours per day, the higher the positive emotion, reflecting a significant relation(P<0.01) 3) Causes from performing duties among function-related causes diclosed a statistically significant relation among marital status, career, monthly income, and positions(P<0.01) 4) Causes from wages showed a statistically significant relation in the average number of working hours per day(P<0.01), monthly income(P,0.05), and positions(P<0.05) 5) Causes from supervision exposed a significant relation in workplaces(P<0.01) 6) Causes from promotion represented a significant relation in positions(P<0.001) 7) Causes from opportunnities for taking a job as seen from external environment causes also disclosed a statistically significant relation in workplaces(P<0.05) 8) Reponsibility for family sustenace reflected a statistically significant relation in sex, age, marital status, career, monthly income, work fields, term of employment, positions, and experience of separation(P<0.001) 9) Functional satisfaction showed a statistically significant relation in marital status, career, monthly income, and the average number of hours a day(P<0.05) 10) Oraganizational commitment disclosed a statistically significant relation in work experience, monthly income, term of employment, positions(P<0.05) and the average number of working hours a day(P<0.001) 11) The intention to remain indicated a statistically significant relation in age, marital status, work experience, monthly income, positions(P<0.001) and term of employment. the average number of working hours a day(P<0.01), and in the performing work field(P<0.05)

• International Journal of Control, Automation, and Systems
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• v.1 no.1
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• pp.149-155
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• 2003

In this study, we introduce the main ideas on the control and strategy used by the robot soccer team of the Universidad de Buenos hires, UBA-Sot. The basis of our approach is to obtain a cooperative behavior, which emerges from homogeneous sets of individual behaviors. Except for the goalkeeper, the behavior set of each robot contains a small number of individual behaviors. Basically, the individual behaviors have the same core: to move from the initial to-ward the target coordinates. However, these individual behaviors differ because each one has a different precondition associated with it. Each precondition is the combination of a number of elementary ones. The aim of our approach is to answer the following questions: How can the robot compute the preconditions in time\ulcorner How are the control actions defined, which allow the robot to move from the initial toward the final coordinates\ulcorner The way we cope with these issues is, on the one hand, to use ball and robot predictors and, on the other hand, to use very fast planning. Our proposal is to use planning in such a way that the behavior obtained is closer to a reactive than a deliberative one. Simulations and experiments on real robots, based on this approach, have so far given encouraging results.

• Journal of the Korean Regional Science Association
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• v.34 no.2
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• pp.35-47
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• 2018

This research aims to examine the spatial patterns of vacant housings and the factors determining housing vacancy in Daegu using individual-level building DB. The results of the spatial pattern analysis showed a donut shaped-spatial concentration of vacant housings in the central areas of the city. The results of logistic regression analysis revealed that not only individual building characteristics, such as building area, number of floors, and building age, but also socio-economic characteristics of community, such as urban redevelopment district, number of adjacent vacancies, recent population change, and ratio of elderly, are important factors affecting housing vacancies.

• Information Systems Review
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• v.18 no.2
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• pp.23-38
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• 2016

Previous studies on information systems (IS) and finance suggest that information on stock message boards influence the investment decisions of individual investors. However, how information on online stock message boards influences an individual investor's buy or sell decisions is unclear. To address this research question, we investigate the relationship between a number of posts on stock message boards and order imbalance in stock markets. Order imbalance is defined as the difference between the daily sum of buy-side shares traded and the daily sum of sell-side shares traded. Therefore, order imbalance can suggest the direction of trades and the strength of the direction with trading volumes. In this regard, this study examines how the number of posts (information on stock message boards) influences order imbalance (stock trading behavior). We collected about 46,077 messages of 40 companies on the Korea Composite Stock Price Index from Paxnet, the most popular Korean online stock message board. The messages we collected were divided based on in-trading and after-trading hours to examine the relationship between the numbers of posts and trading volumes. We also collected order imbalance data on individual investors. We then integrated the balanced panel data sets and analyzed them through vector regression. We found that the number of posts on online stock message boards is positively related to prior order imbalance. We believe that our findings contribute to knowledge in IS and finance. Furthermore, this study suggests that investors should carefully monitor information on stock message boards to understand stock market sentiments.