콘크리트의 균열과 크기효과 예측을 위한 유한요소해석

박경수(Park, Kyoungsoo),하경수(Ha, Kyoungsoo) 한국콘크리트학회 2012 한국콘크리트학회 학술대회 논문집 Vol.2012 No.5

Stabilization Process Analysis of Cable Dome Structure

Kyoungsoo Lee,Sang-Eul Han,박대효 한국강구조학회 2012 International Journal of Steel Structures Vol.12 No.4

In this paper, a stabilization process of cable dome structures, Sky-parasol, was simulated by using dynamic relaxation method (DRM) with kinetic damping technique and curved catenary cable element. Using the algorithm of this paper, an initially drooped catenary shape of cable dome can be obtained by deleting some diagonal and under cable from the initial design shape for the erection process analysis. This process can be understood as collapse process analysis. Next, the analysis model was prepared by inserting the diagonal and under cables for erection process analysis from the resulting shape of collapse process analysis. The element force of cable and change of the shape of cable dome are obtained from the erection process analysis by increasing the incremental stress-jacking force of diagonal cables. By using the method of this study, it is possible to simulate the characteristics of cable dome for shape finding and determination of member forces during stabilization process analysis.

Three-dimensional finite element analysis for estimation of the weld residual stress in the dissimilar butt weld piping

Kyoungsoo Lee,Maanwon Kim,Sungho Lee 대한기계학회 2013 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.27 No.1

Numerous dissimilar metal welds are used to connect carbon steel and stainless steel in nuclear power plants. Recently, some cracks have occurred in the dissimilar metal welds, and welding residual stress is considered as a contributing factor to the cracks. In this study, welding residual stresses in dissimilar butt weld piping were evaluated by the 3-dimensional (3-D) finite element method. Welding residual stresses along the circumference of heat affected zones as well as weld regions were obtained through the analysis, which could not be obtainable with 2-dimensional (2-D) analysis. The differences between 2-D analysis and 3-D analysis are presented in this paper.

RFID Based Indoor Positioning System Using Event Filtering

Kyoungsoo Bok,Jaesoo Yoo 대한전기학회 2017 Journal of Electrical Engineering & Technology Vol.12 No.1

Recently, location systems using RFID technology have been studied in indoor environments. However, the existing techniques require high computational cost to compute the location of a moving object because they compare the location proximity of all reference tags and objects. In this paper, we propose an RFID based location positioning scheme using event filtering, which reduces the computation cost of calculating the locations of moving objects while maintaining the accuracy of location estimation. In addition, we propose an incremental location update policy to reduce the location update cost for moving objects. We also compare the proposed scheme with one of the localization schemes, LANDMARC using a performance evaluation. As a result, the proposed scheme outperforms LANDMARC in terms of the computational cost of location estimation. The proposed scheme also reduces the cost of location update by using the RFID-based update policy.

Provenance Compression Scheme for Managing Large RDF Documents

Kyoungsoo Bok,Jieun Han,Jongtae Lim,Jaesoo Yoo 한국정보기술학회 2019 Proceedings of The International Workshop on Futur Vol.2018 No.1

In this paper, we propose a new RDF provenance compression scheme that considers graph patterns. The proposed scheme reduces the space occupied by string data by converting the provenance data into numeric data through a dictionary encoding process. The proposed scheme reduces the storage space by compressing the source RDF documents by considering their patterns. It also compresses the provenance data by considering the patterns of active nodes in the PROV model. This improves the compression performance through a compression based on the provenance flow. The excellence of the proposed scheme was verified based on the compression rate and processing time determined from a performance evaluation.

Strategic Orientation, Integrated Marketing Communication, and Relational Performance in E-commerce Brands: Evidence from Japanese Consumers’ Perception

Kyoungsoo Kang 한국경영커뮤니케이션학회 2021 Business Communication Research and Practice Vol.4 No.1

Objectives:The effect of integrated marketing communications (IMC) has not received sufficient attention in the e-commerce context. The objective of this research was to examine the effects of customer orientation and technology orientation on IMC and relational performance (i.e., trust, commitment, loyalty). Methods:Three hundred valid responses were obtained via questionnaire from e-commerce shoppers (e.g., Amazon, Rakuten, and Yahoo Shopping) in Japan. The partial least squares structural equation modeling procedure was utilized to examine the measurement models and test the research hypotheses. Results:IMC antecedents of strategic orientations, such as customer orientation and technology orientation, were found to positively influence IMC consistency. Technology orientation was found to exert a more significant role in the development of IMC consistency than customer orientation. In addition, all three factors of relational performance were found to be affected by IMC consistency, with the most significant impact found for brand trust. This study found that customer attitudes towards brand trust and commitment mediated the relationship between IMC and brand loyalty. Conclusions:These findings suggest that marketing managers responsible for e-commerce brand promotion and other branding activities need to evaluate the relative contributions of IMC antecedents of strategic orientations. Furthermore, if consumers perceive a consistent message and image of e-commerce brands, they are more likely to learn more about them, develop positive feelings, and actively promote them to others. To improve brand loyalty, the establishment of brand trust and commitment appears to be crucial.

Performance Limitations of Subcarrier Multiplexed WDM Signal Transmissions Using QAM Modulation

Kyoungsoo Kim,Jaehoon Lee,Jichai Jeong IEEE 2009 Journal of lightwave technology Vol.27 No.18

<P>We theoretically investigate the performance limitations of subcarrier multiplexed (SCM) wavelength-division-multiplexing (WDM) systems using optical double-sideband (DSB) modulated, 16-quadrature amplitude-modulated (QAM) signals. The performance limitations are investigated using crosstalk power and SCM channel spacing for various transmission conditions, including impairment factors such as dispersion and fiber nonlinearities for a single wavelength channel first. The effects of WDM channel spacing on SCM systems with multiwavelength channels are also evaluated via the calculated bit error rate (BER) performance, based on the performance limitations found in the single-wavelength simulation. This enables us to provide guidelines for the design of SCM/WDM systems for fiber-to-the-home (FTTH) network in WDM-passive optical network (PON) architecture, based on the performance limitations.</P>

User Reputation computation Method Based on Implicit Ratings on Social Media

( Kyoungsoo Bok ),( Jinkyung Yun ),( Yeonwoo Kim ),( Jongtae Lim ),( Jaesoo Yoo ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.3

Social network services have recently changed from environments for simply building connections among users to open platforms for generating and sharing various forms of information. Existing user reputation computation methods are inadequate for determining the trust in users on social media where explicit ratings are rare, because they determine the trust in users based on user profile, explicit relations, and explicit ratings. To solve this limitation of previous research, we propose a user reputation computation method suitable for the social media environment by incorporating implicit as well as explicit ratings. Reliable user reputation is estimated by identifying malicious information raters, modifying explicit ratings, and applying them to user reputation scores. The proposed method incorporates implicit ratings into user reputation estimation by differentiating positive and negative implicit ratings. Moreover, the method generates user reputation scores for individual categories to determine a given user`s expertise, and incorporates the number of users who participated in rating to determine a given user`s influence. This allows reputation scores to be generated also for users who have received no explicit ratings, and, thereby, is more suitable for social media. In addition, based on the user reputation scores, malicious information providers can be identified.

Ultimate load capacity of unit Strarch frames using an explicit numerical method

Kyoungsoo Lee,Jung-Wuk Hong,Sang-Eul Han 국제구조공학회 2012 Steel and Composite Structures, An International J Vol.13 No.6

This study uses an explicit numerical algorithm to evaluate the ultimate load capacity analysis of a unit Strarch frame, accounting for the initial imperfection effects of the stress-erection process. Displacement-based filament beam element and an explicit dynamic relaxation method with kinetic damping are used to achieve the analysis. The section is composed of the finite number of filaments that can be conveniently modeled by various material models. Ramberg-Osgood and bilinear kinematic elastic plastic material models are formulated to analyze the nonlinear material behaviors of filaments. The numerical results obtained in the present study are compared with the results of experiment for stress-erection and buckling of unit Strarch frames.

A Friend Recommendation Scheme in Social Network Environments

Kyoungsoo Bok,Hyeonwook Jeon,Chunghui Lee,Jaesoo Yoo 한국콘텐츠학회 2016 International Journal of Contents Vol.12 No.2

In this paper, we propose a friend recommendation scheme that takes into consideration the attribute information of a POI and a user’s movement patterns. The proposed scheme broadly consists of a part that filters out other users who have different preferences by calculating preferences using the attribute information of users and a part that finds a moving trajectory close to that of a user with a pattern-matching scheme. To verify the superiority of the proposed scheme, we compare it with existing schemes through various performance evaluations.