• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1482-1487
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• 2003

This paper presents a new family of 4-DoF parallel mechanism with two platforms. The new mechanism is composed of front and rear platforms, and three limbs. Two limbs with 6dof joint (P-P-S-P) are attached to the each platform and are perpendicular to baseplate, while the middle limb with 4-Dof joints (R-R-R-P or R-R-P-P) is attached to the revolute joint that connect front and rear platform. The two-DoF-driving mechanism at the middle limb with two base-fixed prismatic actuators can generate the heaving and roll motions or two translational motions. Therefore, Therefore, the new 4-Dof parallel mechanism (1T-3R) can generate pitch motions at each platforms, roll, and heaving motions, while another type of new 4-Dof parallel mechanism (2T-2R) can generate pitch motions at each platforms, x and z translational motions. For 1T-3R mechanism, kinematic analyses including inverse, forward kinematics, and Jacobian are performed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1352-1357
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• 2011

Heights of a platform above the rail for the passenger train in the country are classified into two categories such as the low level (500mm; mainline) and the high level (1,135mm; metropolitan subway line) platforms. In order to operate similarly both a mainline railroad and a metropolitan subway line, as the requisite door safety system, it is necessary to develop the doorstep equipment of the rolling stock regardless of both the low and high level platforms. In this study, the application of doorstep equipments to use mixed with two types of platforms are examined on the supposition that the train only for the low level platform stops in the both low and high level platforms.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.484-489
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• 2011

Heights of a platform above the rail for the passenger train in the country are classified into two categories such as the low level (500mm; mainline) and the high level (1,135mm; metropolitan subway line) platforms. In order to operate similarly both a mainline railroad and a metropolitan subway line, as the requisite door safety system, it is necessary to develop the doorstep equipment of the rolling stock regardless of both the low and high level platforms. In this study, performance requirements of doorstep equipments used for two types of platforms are examined on the supposition that the train only for the low level platform could stop in the both low and high level platforms.

• KDI Journal of Economic Policy
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• 제44권4호
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• pp.25-42
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• 2022

I analyze how the food delivery market's indirect network effect and spillover effect influence the spread of food delivery platforms in different counties. This study finds that there is a positive local indirect network effect and a positive spillover effect in the adoption of the platform by examining the food delivery platform market in South Korea as of 2020. As food delivery platforms secure consumers who use them, more restaurants on the other side of a two-sided market adopt such platforms (indirect network effect). The spillover effect would allow other restaurants in a region to become more likely to adopt food delivery platforms if there are a greater number of restaurants in the region that use such platforms. This study contributes to the comprehension of technology diffusion and the marketing strategies of platform providers by providing empirical evidence of both effects.

• 한국의류산업학회지
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• 제25권1호
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• pp.24-40
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• 2023

Contemporary consumers' acceptance of second-hand products has been increasingly improving worldwide, especially in China. Based on the Extended Unified Theory of Acceptance and Use of Technology, we developed and empirically validated a research framework to predict consumers' motivation to use re-commerce platforms. We explored the diverse factors influencing mobile commerce usage through re-commerce platforms. Furthermore, this study investigated the role of gender differences as a factor moderating the association between several constructs and the intention to use re-commerce platforms. A total of 226 consumer responses were collected. The results indicated that hedonic motivation, performance expectancy, consumer habits, social influence, and price value affect consumers' attitudes toward re-commerce platforms. The effects of the attitude toward re-commerce platforms on the intention to use these platforms were also statistically significant. When effort expectancy, hedonic motivation, and consumer habits in re-commerce platform usage increase, male consumers' attitude toward its usage, in particular, also increases. Meanwhile, when performance expectancy, hedonic motivation, and consumer habits in re-commerce platform usage increase, the attitude toward its usage increases among female consumers. Moreover, our results indicate that the two gender groups present different characteristics regarding re-commerce platform usage. Therefore, this study offers a theoretical basis for future analyses of second-hand trade.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.107.5-107
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• 2002

In this paper, a kinematic optimal design of a new paralleltype rolling mill based upon two Stewart platforms manipulator is investigated. The objective of this new parallel-type rolling mill is to permit an integrated control of the strip thickness, strip shape, pair crossing angle, uniform wear of the rolls, and tension of the strip. A manipulability measure, as the ratio of the manipulability ellipsoid volume and the condition number of a split Jacobian matrix, is defined. Two kinematic parameters, the radius of the base and the angle between two neighboring joints, are optimally designed by maximizing the global manipulability measure in the entire workspace.

• 한국게임학회 논문지
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• 제16권6호
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• pp.173-184
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• 2016

본 연구는 전통적인 양면시장인 게임산업에서 게임개발사들이 선택하는 플랫폼 전략을 모바일 게임플랫폼을 대상으로 탐색하였다. 온라인과 오프라인에 존재하는 관련 콘텐츠를 대상으로 자료를 수집하여 주제를 추출하는 콘텐츠 질적 분석을 실시하였으며 연구의 신뢰도와 타당도를 높이기 위하여 게임개발사의 임원 4명과 추가로 심층면접을 실시하였다. 연구결과는 첫째, 게임개발사의 플랫폼 선택 요인은 게임 구현능력과 기술적 안정성, 플랫폼의 마케팅능력, 그리고 수익성 창출이다. 둘째, 가치창출과 가치확보에 따라서 모바일 게임플랫폼은 SNS중심의 모바일 1세대 게임에서 마켓플레이스를 중심으로 하는 모바일 2세대 게임으로 플랫폼 주도권을 넘겨주었다.

• 국제초고층학회논문집
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• 제3권4호
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• pp.279-283
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• 2014

This paper introduces two platforms created by the development team at CORE studio, Thornton Tomasetti's global innovation studio. Collaborative platforms change the way that parties communicate and develop projects. Wikipedia is one of many great examples for a platform that supports collaborative development of a product - the world's largest encyclopedia. In the AEC industry, no such platform exists that can be used for collaborative development of a building project, and hence, information exchange between the parties involved, and modeling programs used in a project is slow and opaque. The platforms introduced in this paper allow for much greater transparency at all stages of the building design process, and hence improve the flow of information between parties involved in the process, both firm-internal and external. While traditionally, the use of a large number of different modeling and analysis platforms is hard to manage by a project team; this paper introduces methods that strengthen the design process by using a multitude of programs needed in the different building design phases.

• Asia pacific journal of information systems
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• 제34권1호
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• pp.191-208
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• 2024

This paper proposes the presence and importance of cultural differences to address user engagement in worldwide social media platforms. Based on Hofstede's cultural dimensions, this paper addresses their new meanings in the context of user engagement in social media. Our propositions address two research questions: (1) how do cultural dimensions, displayed on social media platforms, differ across national cultures?; (2) what different preferences the social media platforms have in terms of which cultural dimensions promote or suppress user engagement? User engagement in social media platforms is explained by the cultural differences in terms of the four cultural dimensions: individualism vs. collectivism, uncertainty avoidance, power distance, and masculinity vs. femininity. Implications are also discussed for research and practice.

• 한국운동역학회지
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• 제17권1호
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• pp.1-8
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• 2007

Ground reaction force (GRF) measures are one of the most commonly used in biomechanical study. GRF system is very useful educational tool to explain and demonstrate the Newton's law of universal gravitation and laws of motion as well. However, accuracy, intra- and inter- force platform measures' consistency, reliability, noise, and the effect of platform mounting to GRF measures were not clearly viewed. The aim of this study was to examine the above. GRFs of a plastic dummy and two subjects' quiet upright standing were collected at four university laboratories eight force platforms. The types of platforms, analysis programs, and platform set-up were various. Three 100s-trials were conducted with sampling frequency of 100 Hz. First two trials' vertical component of GRFs, Fz, and CoP sway ranges of mid-60s-portion of 100s trials were analyzed by the paired t-tests and one-way ANOVA. Six of eight platforms' 1st and 2nd trial dummy Fz were statistically different (p<.05) and all platforms ICC were poor (<.28). Fz of the two platforms in every four laboratories were statistically different (p<.05). There were white noises and/or very distinctive noises at specific frequency ranges in all Fz measures. 5 Hz low-pass filtering made clear the Fz differences. CoP ranges of dummy were less than 0.5 cm and the best was 0.02 cm. This CoP range finding agrees with previous results suggests the importance of force platform mounting and A/D card resolution.