• International Journal of Aeronautical and Space Sciences
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• v.16 no.4
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• pp.581-589
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• 2015

This paper describes a monocular vision-based formation flight technology using two fixed wing unmanned aerial vehicles. To measuring relative position and attitude of a leader aircraft, a monocular camera installed in the front of the follower aircraft captures an image of the leader, and position and attitude are measured from the image using the KLT feature point tracker and POSIT algorithm. To verify the feasibility of this vision processing algorithm, a field test was performed using two light sports aircraft, and our experimental results show that the proposed monocular vision-based measurement algorithm is feasible. Performance verification for the proposed formation flight technology was carried out using the X-Plane flight simulator. The formation flight simulation system consists of two PCs playing the role of leader and follower. When the leader flies by the command of user, the follower aircraft tracks the leader by designed guidance and a PI control law, and all the information about leader was measured using monocular vision. This simulation shows that guidance using relative attitude information tracks the leader aircraft better than not using attitude information. This simulation shows absolute average errors for the relative position as follows: X-axis: 2.88 m, Y-axis: 2.09 m, and Z-axis: 0.44 m.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2002.11a
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• pp.44-55
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• 2002

This paper tried to analyse the factors influencing consumer trust and the relationships between cause variables and results in Internet Shopping Mall. In order to do so, this paper tried to analyse the trust factors in TV Home Shopping as well as Internet Shopping Mall in terms of cyber markets both. There found six factors: perceived factor before purchasing, perceived factor after purchasing, perceived and emotional factors in the course of purchasing, posit ive and negative emotional factors after purchasing. These factors are correlated with internet shopping variables and we can measure how Internet shopping variables can affect trust to the shopping mall. We can compare the trust factors of TV home shopping with those of Internet shopping Mall. and then we can activate Internet Shopping Mall. More implications of this study and further researches should be discussed in the future research.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.596-602
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• 2002

An easy elevator for learning originated is opened to compare the existed learning equipment, and it had a high studying efficient that the sequence control circuit can opens and closes with the wire. The structure of equipment to be controlled from the first floor to the fifth floors is demonstrated a constructive apparatus by a lamp atc to express the function of the open-close of the door according to the cage moving with a mechanical actuation of the forward-reverse breaker and the motor of load and a mechanical actuation of hand-operation control components of push-button S/W and L/S and relay etc. These components let connects each other in order to control of the elevator function with the auto program and the designed sequence control circuit. Consequent1y the process of these functions of 1~5steps could operates the cage with an auto program of the elevator and the sequence control circuit. The sequence control circuit is controlled by the step of forward and reverse to follow as that the sensor function of the L/S1~L/S5 let posit with the control switchs of S/W1~S/W5 of PLC testing panel and switchs of S/W1~S/W5 installed on the transparent acryl plate of the frame. In here, improved apparatus is a hand-auto operation combined learning equipment to study the principle and a technique of the originated sequence control circuit and the auto program of PLC.

• Journal of Digital Convergence
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• v.14 no.1
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• pp.131-139
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• 2016

Given social problems of service addiction such as mobile messenger services(MMSs), many studies on service management and information systems have examined the negative outcomes of service addiction. MMS addiction significantly influences user's health and academic performance. In this regard, this study investigated the effects of MMS addiction on user's health and academic performance problems. We posit personal traits and service features as key antecedents of MMS addiction. The research framework was tested by using survey data collected from 162 university students who have frequently used Kakaotalk. The analysis results found that MMS addiction significantly influences users' health and academic performance problems. The findings of this study indicate that self-esteem and self-control play an important role in generating MMS addiction. While attention significantly affects MMS addiction, social relationship formation and perceived enjoyment are not significantly associated with MMS addiction. The analysis results help MMS providers and government establish policies or guidelines to induce healthy MMS use.

• Journal of Korea Technology Innovation Society
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• v.21 no.2
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• pp.560-586
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• 2018

This study empirically analyzes how factors inside university influence the creation of technology-based spin-offs, employing unique data sets. We posit a two-year time lag between the explanatory variables and the dependent one using total 270 university data sets for 5 years in Korea. The results show that universities with experienced technology licensing offices (TLO), those with R&D personnel size, those in possession of incubation policies or business incubators have an edge in creating technology-based spin-offs. The findings provide policy implications. By making more informed decisions on fostering technology-based spin-offs at universities, policymakers can promote the creation of new industries and lead them to create jobs in line with the national economic growth policy.

• Journal of Digital Convergence
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• v.12 no.3
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• pp.95-103
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• 2014

Given social problems of technology addiction such as games and mobile messenger services (MMSs), it have become important to understand theoretical mechanisms to generate technology addiction. In this vein, this study examined key antecedents of technology addiction in the MMS environment. We posit technology habit and user satisfaction as key predictors of technology addiction. In addition, the impacts of social interaction and flow on use's technology addition formation were investigated The research framework was tested by using survey data collected from 278 Kakaotalk users who have used more than 6 months. The analysis results found that both technology habit and user satisfaction play an important role in generating technology addiction in the MMS context. The findings of this study indicate that social interaction and flow significantly affects technology habit and user satisfaction. The analysis results help government and MMS providers establish policies or strategies to induce healthy MMS use.

• Journal of Science and Technology Studies
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• v.12 no.1
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• pp.45-78
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• 2012

What is a disaster? And what can science and technology studies tell us about it? There might be numerous definitions about disaster. In this article, we will posit that disaster is an incident when sociotechnical system actor-network broke down against the other force in their "trial of strength". This is a process that punctualized actor-network is depunctualized, and a status that readiness-to-hand of Being recedes while pesentness-at-hand of tool-being comes forward. Using the concept of disaster as a case study, we will consider how Latourian ontology overlaps with Heideggerian philosophy of technology. This STS approach which hasn't been previously studied might provide us with new theoretical framework that enables us to construe the assemblage of technoscience and nature-society in the field of PUS or NPSS.

• Journal of agriculture & life science
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• v.43 no.2
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• pp.55-63
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• 2009

This paper analyzes the effects of Korea-US FTA on the pork market in Korea. Without distinction of chilled and frozen pork, previous studies that investigate the impacts of FTA posit single category of pork. Moreover, many prior studies assume the domestic pork and imported one are homogenous. This study fills this gap. The simulated influences of Korea-US FTA on the price of domesitc pork are -2.69 to -15.96 percents. The FTA is simulated to result in the fall of domestic production by 1.35 to 5.6 percents.

• Journal of Digital Convergence
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• v.19 no.9
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• pp.145-156
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• 2021

While the current literature has considered business group as a temporary form of organizations that only exists under the developing contries with under-developed financial markets. Chaebol, a form of businss group in Korea, has sustained as a major organization form in Korea. To fill the current gap in the literature and practice, I suggest a theoretical model of Chaebol scion's entrepreneurial firm growth mechanisms. First, I posit that social, structural, and psychological factors motivate Chaebol scions to engage in entrepreneurship. Second, I suggest that five mechanisms, including business opportunity, financial support, recruitment, marketing, and inter-organizational collaboration, will facilitate entrepreneurial firm growth. By constituting a model of Chaebol scion's entrepreneurial firm growth, the current theoretical paper advances the literature on business group and entrepreneurship with indicating Korean Chaebol's new expansion possibilities.

• Journal of the Korea Convergence Society
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• v.10 no.8
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• pp.217-226
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• 2019

This study examines the effect of the wedge between voting rights and cash flow rights of controlling shareholders on the implied cost of equity. Prior studies posit that controlling shareholder's voting rights exceeding cash flow rights causes expropriating minority shareholders. Using date from 793 group-affiliated Korean firms for 10 years from 2005 to 2016, the result shows that there is a positive and significant relationship between controlling shareholders' wedge and implied cost of equity. This result implies that investors regard the controlling shareholders' wedge as potential agency cost in which they require additional risk premium because controlling shareholders have a strong incentive to pursue their private interests trough tunneling practices.