• International Journal of Control, Automation, and Systems
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• v.2 no.2
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• pp.171-181
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• 2004

An autonomous navigation algorithm for marine vehicles is proposed in this paper using fuzzy logic under COLREG guidelines. The VFF (Virtual Force Field) method, which is widely used in the field of mobile robotics, is modified for application to the autonomous navigation of marine vehicles. This Modified Virtual Force Field (MVFF) method can be used in either track-keeping or collision avoidance modes. Moreover, the operator can select a track-keeping pattern mode in the proposed algorithm. The collision avoidance algorithm has the ability to handle static and/or moving obstacles. The fuzzy expert rules are designed deliberately under COLREG guidelines. An extensive simulation study is used to verify the proposed method.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2006.10a
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• pp.144-153
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• 2006

In order to take TC forecasts from different observatories into consideration, and make quantitative assessment and analysis for avoiding TC routes from the view of safety and cost, a new safe-economic decision making method of TC avoidance routing on ocean was put forward. This model is based on combining forecast of TC trace based on neural networks, technical method to determine the future TC wind and wave fields, technical method of fuzzy information optimization, risk analysis theory, and meteorological-economic decision making theory. It has applied to the simulation of MV Tianlihai's shipping on ocean. The result shows that the model can select the optimum plan from 7 plans, the selected plan is in accordance with the one selected by experienced captains.

• Korea Trade Review
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• v.46 no.4
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• pp.131-148
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• 2021

This study examines how corporate social responsibility (CSR) affects corporate tax avoidance behavior. Using a sample of publicly listed U.S. firms, we find that legal CSR-which is required by law-reduces the level of corporate tax avoidance because this type of CSR reduces information asymmetry between investors and corporate management in such a way that investors are less likely to perceive tax avoidance behavior as a risk. On the other hand, we find that the relationship between normative CSR-which is a voluntary type of CSR behavior-and tax avoidance is not statistically significant. Instead, our additional analysis reveals that normative CSR increases the level of corporate tax avoidance conditional on reporting quality. This study provides meaningful implications to the academic literature and to practitioners. Not only does this study highlight the fact that not all CSR are alike, it highlights that it is important to provide transparent CSR information in order to allow stakeholders to estimate the net effects of firms' CSR activities and tax payment.

• Asia pacific journal of information systems
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• v.33 no.4
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• pp.1016-1035
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• 2023

Corporate tax avoidance has been the subject of international debate since the Enron scandal and has raised awareness of the need for greater transparency in financial markets. Efforts have been made to strengthen financial reporting requirements and meet the needs of investors and other stakeholders, including digitalization of financial reporting through Extensible Business Reporting Language (XBRL). This study examines the impact of the mandatory adoption of XBRL on corporate tax avoidance. We tested our predictions using a panel dataset of Indonesian firms listed on the IDX stock exchange. Based on available information in the DATASTREAM database covering the 2013-2017 period, we used two proxies for tax avoidance i.e., GAAP effective tax rate and current effective tax rate. We estimated multiple regression model including industry and year fixed effects. The results show that XBRL implementation has reduced corporate tax avoidance. These findings suggest that improving corporate transparency through XBRL could play a deterrent tool to corporate tax avoidance. The results of this study should be useful to tax authorities and accounting standard setters supporting the benefits of digitalizing financial reporting and continuing to complete XBRL taxonomies around the world.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2011.11a
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• pp.34-36
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• 2011

In recent years, shipping at the sea has been rapidly grown in marine nations and vessel's collisions are increasing as well. The collision avoidance is one of issues maritime safety. To reduce vessels' collisions, the fuzzy inference system is one of popular algorithms for collision avoidance. In this paper we aim to implement Matlab. Fuzzy logic toolbox software for collision avoidance algorithm. For this we used an original Matlab fuzzy logic toolbox and customized the toolbox for the collision avoidance algorithm.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.12
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• pp.2272-2293
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• 2011

Communication technology of future networks is predicted to provide a large variety of services including WiFi service in vehicular network. In this paper, we assume that vehicles are embedded with WiMAX antenna and in-vehicle terminals receive WiMAX traffic through WiFi interface. This assumption will impose severe performance degradation due to interference among mobile BSSs when WiFi access points (APs) are densely located. Existing interference avoidance techniques cannot properly resolve the above problems and do not cope with dynamically moving vehicular scenario since they focus only on the fixed network topology. In this paper, we propose a mobility-aware interference avoidance scheme for WiFi services. The proposed scheme computes the interference duration by exploiting mobility vector and location information of neighboring APs. If the interference duration is not negligible, our scheme searches for another channel in order to avoid interference. However, if the interference duration is negligible, our scheme continues to use the channel to reduce switching overhead. To measure the effectiveness of the proposed scheme against other existing techniques, we evaluated performance by using OPNET simulator. Through the simulation, we obtained about 60% reduction in the maximum interference frequency and about 67% improvement in throughput. Furthermore, our scheme provides fair channel usage.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.2
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• pp.169-177
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• 2019

It is very important to understand the intention of a target ship to prevent collisions in multiple-ship situations. However, considering the intentions of a large number of ships at the same time is a great burden for the officer who must establish a collision avoidance plan. With a distributed algorithm, a ship can exchange information with a large number of target ships and search for a safe course. In this paper, I have applied a Distributed Stochastic Search Algorithm (DSSA), a distributed algorithm, for ship collision avoidance. A ship chooses the course that offers the greatest cost reduction or keeps its current course according to probability and constraints. DSSA is divided into five types according to the probability and constraints mentioned. In this paper, the five types of DSSA are applied for ship collision avoidance, and the effects on ship collision avoidance are analyzed. In addition, I have investigated which DSSA type is most suitable for collision avoidance. The experimental results show that the DSSA-A and B schemes offered effective ship collision avoidance. This algorithm is expected to be applicable for ship collision avoidance in a distributed system.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.1
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• pp.127-132
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• 2018

One of the key issues in the Unmanned Aerial Vehicle (: UAV) technology is the collision avoidance. Specifically, the collision avoidance among multiple UAVs is critical to expand UAV applications to civil sector where large number of UAVs could be operated in the limited space. In this paper, we introduce a collision avoidance scheme based on Flying Ad Hoc Network (: FANET). The proposed scheme adopts collision avoidance mechanism used in wireless data communication networks. Using this scheme UAVs can not only communicate conventional user information, but also share flight information to avoid collision.

• Journal of Distribution Science
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• v.21 no.6
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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.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.939-940
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• 2006

Many researches on path planning and obstacle avoidance for the fundamentals of mobile robot have been done. In this paper, we propose the algorithm of path planning and obstacle avoidance for mobile robot. We call the proposed method Random Access Sequence(RAS) method. RAS method using obstacle information from variable sensors is useful to get minimum path length to goal.