• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.54 no.1
• /
• pp.1-7
• /
• 2005

This paper proposes a novel UPQC(unified power quality conditioner) based on H-bridge modules, isolated through single-phase multi-winding transformers. The dynamic performance of proposed system was analyzed by simulation with PSCAD/EMTDC, assuming that the UPQC is connected with the 22.9kV distribution line. The proposed system can be directly connected to the transmission line without series injection transformers. It has flexibility in expanding the operation voltage by increasing the number of H-bridge modules and can compensate reactive power, harmonics, voltage sag and swell, voltage unbalance. The proposing UPQC has the ultimate capability of improving power quality at the point of installation on power distribution systems.

• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.48 no.10
• /
• pp.579-586
• /
• 1999

This paper describes a simulation model and a scaled hardware model to analyze the dynamic performance of Unified Power Flow Controller, which can flexibly adjust the active power flow through the ac transmission line. The design of control system for UPFC was developed using vector control method. The results of simulation and scaled hardware test show that the developed control system works accurately. Both models would be very effective for analyzing the dynamic performance of the Unified Power Flow Controller.

• Journal of Information Science Theory and Practice
• /
• v.4 no.4
• /
• pp.4-15
• /
• 2016

Information needs of users have been examined both generally and as they pertain to particular types and formats of information. Barriers to information have also been investigated, including those which are situational and also across certain domains and socioeconomic contexts. Unified studies concerning both information needs and barriers are needed. Both are likely always present in any given interactive search situation; further, users' attempts to satisfy their own individualized information needs will likely encounter barriers of some sort. The present study employed a survey method to collect users' perceptions of video information needs and barriers as part of recent video search situations. Findings from this analysis establish a unified framework, based on the themes emerging directly from the responses of users, and present the suitability and benefit for informing future designs and evaluations of user-centered interactive retrieval tools.

• Journal of Power Electronics
• /
• v.15 no.5
• /
• pp.1348-1357
• /
• 2015

Under traditional unified power quality conditioner (UPQC) control, a UPQC series converter (SC) is mainly used to handle grid-side power quality problems while its parallel converter (PC) is mainly used to handle load-side power quality problems. The SC and PC are relatively independent. The SC is usually in standby mode and it only runs when the grid voltage abruptly changes. In this paper, novel UPQC coordinated control strategies are proposed which use the SC to share the reactive power compensation function of the PC especially without grid-side power quality problems. However, in some cases, there will be a circulating current between the SC and the PC, which will probably influence the compensation fashion, the compensation capacity, or the normal work of the UPQC. Through an active power circulation analysis, strategies with and without a circulating current are presented which fuses the reactive power allocation strategy of the SC and the PC, the composite control strategy of the SC and the compensation strategy of the DC storage unit. Both of the strategies effectively solve the SC long term idle problem, limit the influence of the circulating current, optimize all of the UPQC units and reduce the production cost. An analysis, along with simulation andexperimental results, is presented to verify the feasibility and effectiveness of the proposed control strategies.

• The Journal of Information Systems
• /
• v.26 no.4
• /
• pp.303-325
• /
• 2017

Purpose The purpose of this study is to forage for the factors for explaining the adoption behavior of the mobile convenient payment system based on the Personality Trait, Unified Theory of Acceptance and Use of Technology, and Regulatory focus. Design/methodology/approach This study made a design of the research model by integrating the factors of Unified Theory of Acceptance and Use of Technology with the factors of Big five personality traits on the basis of Samrt device environment. In addition, this study, did empirical analysis of the structural equation model by PLS(Partial Least Squares) in order to find out the relationship of personal factors and mobile convenient payment system's features. Findings According to the empirical analysis result, this study confirmed that the acceptance of mobile convenient payment systems is influence by personality traits and factors based on Unified Theory of Acceptance and Use of Technology and trust. In addition, this study find out that the behavior of an adoption of mobile convenient payment systems according to the type of regulatory focus.

• Steel and Composite Structures
• /
• v.34 no.1
• /
• pp.75-89
• /
• 2020

The current paper illustrates the effect of in-plane varying compressive force on critical buckling loads and buckling modes of sandwich composite laminated beam rested on elastic foundation. To generalize a proposed model, unified higher order shear deformation beam theories are exploited through analysis; those satisfy the parabolic variation of shear across the thickness. Therefore, there is no need for shear correction factor. Winkler and Pasternak elastic foundations are presented to consider the effect of any elastic medium surrounding beam structure. The Hamilton's principle is proposed to derive the equilibrium equations of unified sandwich composite laminated beams. Differential quadrature numerical method (DQNM) is used to discretize the differential equilibrium equations in spatial direction. After that, eigenvalue problem is solved to obtain the buckling loads and associated mode shapes. The proposed model is validated with previous published works and good matching is observed. The numerical results are carried out to show effects of axial load functions, lamination thicknesses, orthotropy and elastic foundation constants on the buckling loads and mode shapes of sandwich composite beam. This model is important in designing of aircrafts and ships when non-uniform compressive load and shear loading is dominated.

• The Journal of Information Systems
• /
• v.28 no.2
• /
• pp.181-200
• /
• 2019

Purpose In order to find out the influential factors to accept the mobile convenient payment service like Apple pay or Samsung Pay based on the Unified Theory of Acceptance and Use of Technology according to the type of High and Low value payments. Design/methodology/approach This research model is designed on the factors of Unified Theory of Acceptance and Use of Technology and simultaneously analysed, or performed the empirical analysis of the PLS-SEM(Partial Least Squares structural equation model) in order to forage for the association among mobile convenient payment service's features. Findings According to the empirical analysis consequence, this research confirmed that the adoption of mobile convenient payment services is influence by features on the basis of Unified Theory of Acceptance and Use of Technology, mobility, and trust. Also, this paper figure out that the behavior of an user acceptance of mobile convenient payment services according to the type of high and low value payments.

• Structural Engineering and Mechanics
• /
• v.77 no.5
• /
• pp.691-703
• /
• 2021

Reinforced concrete (RC) beams can be subjected to a complex combination of shear forces (V), torsional moments (T), flexural moments (M) and axial loads (N). This paper proposes a unified approach for the analysis of these elements. An existing model for the analysis of orthogonally reinforced concrete membrane elements subjected to in-plane shear and normal stresses is generalized to apply to the case of beams subjected to the complex loading. The combination of V and T can be critical. Torsion is modelled using the hollow-tube analogy. A direct equation for the calculation of the thickness of the equivalent hollow tube is proposed, and the shear stresses caused by V and T are combined using a simple approach. The development and the evaluation of the model are described. The calculations of the model are compared to experimental data from 350 beams subjected to various combinations of stress-resultants and to the calculations of the ACI and the CSA codes. The proposed model provides the most favorable results. It is also shown that it can accurately model the interaction between V and T. The proposed model provides a unified treatment of shear in beams subjected to complex stress-resultants and in thin membrane elements subjected to in-plane stresses.

• Advances in Computational Design
• /
• v.9 no.1
• /
• pp.1-23
• /
• 2024

Present paper deals with the cost effective design of reinforced concrete building frame employing unified particle swarm optimization (UPSO). A building frame with G+8 stories have been adopted to demonstrate the effectiveness of the present algorithm. Effect of seismic loads and wind load have been considered as per Indian Standard (IS) 1893 (Part-I) and IS 875 (Part-III) respectively. Analysis of the frame has been carried out in STAAD Pro software.The design loads for all the beams and columns obtained from STAAD Pro have been given as input of the optimization algorithm. Next, cost optimization of all beams and columns have been carried out in MATLAB environment using UPSO, considering the safety and serviceability criteria mentioned in IS 456. Cost of formwork, concrete and reinforcement have been considered to calculate the total cost. Reinforcement of beams and columns has been calculated with consideration for curtailment and feasibility of laying the reinforcement bars during actual construction. The numerical analysis ensures the accuracy of the developed algorithm in providing the cost optimized design of RC building frame considering safety, serviceability and constructional feasibilities. Further, Monte Carlo simulations performed on the numerical results, proved the consistency and robustness of the developed algorithm. Thus, the present algorithm is capable of giving a cost effective design of RC building frame, which can be adopted directly in construction site without making any changes.

• Proceedings of the KIEE Conference
• /
• 2006.04b
• /
• pp.241-243
• /
• 2006

This paper describes experimental analysis of UPQC, which is composed of cascaded H-bridges and single-phase multi-winding transformers. The operational characteristic was analyzed through experimental works with a scaled model, and simulations with PSCAD/EMTDC. The UPQC proposed in this paper can be directly connected to the distribution line without series injection transformers. It has flexibility to expand the operation voltage by increasing the number of H-bridge modules. The analysis results can be utilized to design the actual UPQC system applicable for the actual distribution system.