• 반도체디스플레이기술학회지
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• 제20권4호
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• pp.119-124
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• 2021

In a situation where Moore's law, which states that the performance of semiconductor integrated circuits doubles every two years, is showing a limit from a certain point, and it is difficult to increase the performance due to the limitations of exposure technology.In this study, a wafer hybrid method that can increase the degree of integration Various research on bonding technology is currently in progress. In this study, in order to achieve rotational precision between wafers in wafer hybrid bonding technology, modeling of θ_z alignment stage and VCM actuator modeling used for rotational alignment, magnetic field analysis and desgin, control, and evaluation are performed. The system of this study was controlled by VCM actuator, capactive sensor, and dspace, and the working range was ±7200 arcsec, and the in-position and resoultion were ±0.01 arcsec. The results of this study confirmed that safety and precise control are possible, and it is expected to be applied to the process to increase the integration.

• Smart Structures and Systems
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• 제29권4호
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• pp.617-624
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• 2022

A new intelligent adaptive control scheme was proposed that combines the control based on interference observer and fuzzy adaptive s-curve for flight path tracking control of unmanned aerial vehicle (UAV). The most important contribution is that the control configurations don't need to know the uncertainty limit of the vehicle and the influence of interference is removed. The proposed control law is an integration of fuzzy control estimator and adaptive proportional integral (PI) compensator with input. The rated feedback drive specifies the desired dynamic properties of the closed control loop based on the known properties of the preferred acceleration vector. At the same time, the adaptive PI control compensate for the unknown of perturbation. Additional terms such as s-surface control can ensure rapid convergence due to the non-linear representation on the surface and also improve the stability. In addition, the observer improves the robustness of the adaptive fuzzy system. It has been proven that the stability of the regulatory system can be ensured according to linear matrix equality based Lyapunov's theory. In summary, the numerical simulation results show the efficiency and the feasibility by the use of the robust control methodology.

• Structural Engineering and Mechanics
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• 제81권4호
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• pp.493-502
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• 2022

Shear lag phenomenon has long been considered in numerous structural codes; however, the AISC provisions have now no longer proposed any unique equation to calculate the shear lag ratio in bolted connections for angles in general. It is noticeable that, however, codes used in this case are largely conservative and need to be amended. A parametric study consisting of 27 angle sections with equal legs and different with bolted connections was performed to investigate the effects of shear lag on the ultimate tensile capacity of angle members. The main parameters were: steel grade, connection length and eccentricity from the center of the plate, as well as the number of rows of bolts parallel to the applied force. The test results were compared with the predictions of the classical 1-x/l law proposed by Mons and Chesen to investigate its application to quantify the effect of shear lag. A parametric study was performed using valid FE models that cover a wide range of parameters. Finally, based on the numerical results, design considerations were proposed to quantify the effect of shear lag on the ultimate tensile capacity of the tensile members.

• 자동차안전학회지
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• 제14권2호
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• pp.26-38
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• 2022

This paper proposes multiple RLS and actuator performance index-based adaptive actuator fault-tolerant control and detection algorithms for longitudinal autonomous driving. The proposed algorithm computes the desired acceleration using feedback law for longitudinal autonomous driving. When actuator fault or performance degradation exists, it is designed that the desired acceleration is adjusted with the calculated feedback gains based on multiple RLS and gradient descent method for fault-tolerant control. In order to define the performance index, the error between the desired and actual accelerations is used. The window-based weighted error standard deviation is computed with the design parameters. Fault level decision algorithm that can represent three fault levels such as normal, warning, emergency levels is proposed in this study. Performance evaluation under various driving scenarios with actuator fault was conducted based on co-simulation of Matlab/Simulink and commercial software (CarMaker).

• 유통과학연구
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• 제21권6호
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• pp.83-89
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• 2023

Purpose: This paper considers the issue of corporate tax avoidance (CTA) in the distribution of the tax burden across companies in Vietnam because the high level of CTA leads to unfairness in taxation. In particular, we aim for discussing the way to measure the extent of CTA and explore the determinants of CTA that reflect the features of high-tax risk-taking companies. Research design, data and methodology: The study investigates factors influencing the CTA behavior of legal entities listed on the Vietnam stock market between 2012 and 2018 to fill the empirical research vacuum in the country. we employ the dynamic GMM estimate method. Interestingly, CTA is considered through three approaches, including two effective-tax-rate-based methods and especially accrual earnings Results: The results highlight tax - accounting book disparities have significant effects on CTA. In addition, firm size, net asset value, debt leverage, and tax-accounting books are related to CTA. Conclusions: Tax avoidance is shown to have a positive correlation with financial distress in this case. The higher a company's capital adequacy ratio, the fewer tax avoidance opportunities it has. The paper draws some recommendations to deal with tax avoidance that improves the fairness in the distribution of the tax burden among corporations.

• 유통과학연구
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• 제21권6호
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• pp.31-38
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• 2023

Purpose: This paper investigates how companies respond to government regulations and disasters in a risk-managed society, and aims to initiate discussions on the future prospects and challenges. Specifically, it explores how companies can plan to respond to such disasters in the future, and stresses that the law should be to protect people's lives and ensure safety, rather than to punish companies. Research design, data and methodology: The study methodology is based on a review of existing literature, as well as trend analysis through big data analysis. The research analyzes the discourse in our society regarding the enactment of the Serious Accident Punishment Act. Results: This study supports that the Serious Accident Punishment Act should be implemented in a manner that does not impede corporate activities, but rather helps to ensure the safety of citizens' daily lives. The authors call for collaboration between communities, labor unions, and companies in achieving a cooperative governance system for a safer society. Conclusions: It highlights the importance of addressing disasters and government regulations in the context of a risk-managed society, and offers insights for both companies and policymakers on how to navigate these challenges. By prioritizing safety and cooperation, we can work towards building a safer and more resilient society

• 유통과학연구
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• 제21권9호
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• pp.115-121
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• 2023

Purpose: This study aimed to deal with disputes between the seller and the buyer in connection with the Letter of Credit (LC) in a sales contract. The Contracts for the International Sale of Goods (CISG) provides the rules on the fundamental breaches which can lead to termination of the sales contract but the CISG is not enough to govern issues arising from the LC disputes when the sales contract is not clear about the payment terms. This paper tried to find some solutions to the disputes by considering international rules, such as the Principles of European Contract Law (PECL). Research design, data and methodology: The methodology applied in this study was an analysis of some court decisions and extended literature review. Results: The study revealed that in contracts for the sale of international goods, the buyer was obliged to open an LC as manner of payment. If the buyer failed to open an LC or amend the terms of the LC, the seller could avoid the contract because this could deprive the seller's expected interest. Conclusions: Few studies in Korea have been comprehensively analyzed in terms of the obligations of regarding the LC with respect to the CISG in court cases. This study suggests safeguarding the buyer and seller when the LC is considered absolute or conditional.

• 유통과학연구
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• 제21권9호
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• pp.67-79
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• 2023

Purpose: To investigate the intensity of bilateral international trade of the Silk Road Economic Belt (SREB) countries with Kazakhstan, its relationship with logistics (LPI), to assess their contribution to economic growth and distribution of commodity flows. Research design, data, and methodology: The method of analyzing the bilateral trade flow was applied by using the trade intensity index (TII) and a multidimensional regression model describing the relationship between LPI and its components, TII, the volume of exports and imports, GDP. Results: The nature and directions of the relationship between TII and the key components of logistics, the positive impact of LPI on the intensity of trade are established. It is revealed that the intensity of trade between the countries in the direction of the EAEU-Kazakhstan has a greater impact on the growth of LPI than in the opposite direction. At the same time, the higher the level of trade integration and the volume of GDP, the stronger their impact on the efficiency of logistics and distribution of commodity flows. Conclusions: Effective distribution of commodity flows will require the development of logistics components based on the direction of bilateral trade and the size of countries, the intensification of state reforms in the field of international trade and distribution logistics.

• Coupled systems mechanics
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• 제12권4호
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• pp.391-407
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• 2023

This paper presents a static study of a rectangular functional graded material (FGM) plate, simply supported on its four edges, adopting a refined higher order theory that looks for, only,four unknowns,without taking into account any corrective factor of the deformation energy with the satisfaction of the zero shear stress conditions on the upper and lower faces of the plate. We will have determined the contribution of these stresses in the transverse deflection of the plate, as well as their effects on the axial stress within the interfaces between the layers(to avoid any problem of imperfections such as delamination) and on the top and bottom edges of the plate in order to take into account the fatigue phenomenon when choosing the distribution law of the properties used during the design of the plate. A numerical statement, in percentage, of the contribution of the shear effect is made in order to show the reliability of the adopted theory. We will also have demonstrated the need to add the shear effect when the aspect ratio is small or large. Code routines are programmed to obtain numerical results illustrating the validity of the model proposed in the theory compared to those available in the literature.

• 유통과학연구
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• 제21권4호
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• pp.57-67
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• 2023

Purpose: This study aims to measuring the employee performance distributions of company in using relationship analysis between motivation, organization learning, compensation, and Organizational commitment. Research design and methodology: The study was conducted on 102 employees as a sample. Data were analyzed using Path Analysis in Structural Equation Modeling (SEM) with PLS. Results: the research result has shown that motivation and compensation have a positive significant effect on organizational commitment. While organizational learning has negative and insignificant effect on organizational commitment. Furthermore, motivation, organizational learning and motivation have no significant effect on employee performance distribution and organizational commitment has a positive significant effect on employee performance distribution. Results for mediating effect has obtained where organizational commitment mediates the effect of motivation and compensation on employee performance distribution, but cannot mediate the effect of organizational learning on employee performance distribution. Conclusion: Organizational commitment in this study can make employees feel comfortable and attached to the company so that employees can perform well to achieve company goals. Motivation and compensation are driving factors in improving employee performance distribution and will achieved if employees have good organizational commitment. In this study, organizational learning is not an important factor in improving employee performance distribution.