• Journal of Aerospace System Engineering
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• v.18 no.2
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• pp.56-63
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• 2024

As the safety of unmanned vehicles continues to improve, their usage in urban environments, which are full of obstacles such as buildings, is expected to increase. When numerous unmanned vehicles are operated in such environments, an algorithm that takes into account mutual collision avoidance, as well as static and dynamic obstacle avoidance, is necessary. In this paper, we propose an algorithm that handles task assignment and path planning. To efficiently plan paths, we construct a grid-based map and derive the paths from it. To enable quick re-planning in dynamic environments, we focus on reducing computational time. Through simulation, we explain obstacle avoidance and mutual collision avoidance in small-scale problems and confirm their performance by observing the entire mission completion time (Makespan) in large-scale problems.

• Journal of Navigation and Port Research
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• v.32 no.5
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• pp.415-423
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• 2008

The purpose of this study is to show a course development of the marine leisure sport policy in Korea. The preceding researches and the analysis on the actual conditions on marine leisure sport in Korea were conducted for this research. And analyzing the obstacle and development factors in marine leisure sport, the conclusions intended to provide the preliminary data on the marine leisure industry are as follows: First, as policy-based problems, there will be needs for the public perception improvement in the marine culture caused by the lack of publicity, the reflection reinforcement of the national policy on the marine leisure industry, the prevention of the overlapping investment for the national resources development in the marine industry and marine leisure sport complexes, and the reinforcement of the close networks with the developed countries. Second, as human-based problems, there will be needs for the new organization of the specialty agencies involved in the marine leisure industry field, the nurture of the capable specialists and the reinforcement and nurture of TF team for the infrastructure industry. Third, as facility-based problems, there appeared to be the expansion of the SOC related to the marine leisure, the ease of the laws and regulations for the development of the marine leisure facilities, the prevention of the thoughtless development caused by close cooperation system with the local government. Fourth, as law and institution-based problems, there appeared to be the abolishment of the regulation-centered laws involved in them, the prevention of the legal and institutional confusion caused by policy confusion. Fifth, as industry-based problems, there must be the expansion of the domestic supply and demand, the reinforcement of parts industry and the nurture of the license system for the mechanics on the vessels and the engines.

• Journal of applied mathematics & informatics
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• v.31 no.1_2
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• pp.55-63
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• 2013

In this paper, a general technique is proposed for solving a system of fourth-order boundary value problems. The solution is given in the form of series and its approximate solution is obtained by truncating the series. Advantages of the method are that the representation of exact solution is obtained in a new reproducing kernel Hilbert space and accuracy of numerical computation is higher. Numerical results show that the method employed in the paper is valid. Numerical evidence is presented to show the applicability and superiority of the new method.

• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.1284-1292
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• 2015

As visual surveillance systems become more and more common in human lives, approaches based on these systems to solve security problems in practice are boosted, especially in railway applications. In this paper, we first propose a robust snag detection algorithm and then present a railway security system by using a combination of multiple sensors and the vision based snag detection algorithm. The system aims safety at several repeatedly occurred situations including slope protection, inspection of the falling-object from bridges, and the detection of snags and foreign objects on the rail. Experiments demonstrate that the snag detection is relatively robust and the system could guarantee the security of the railway through these real-time protections and detections.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.14
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• pp.397-426
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• 2000

Since the internet is open to public in 1990, electronic commerce(EC) user has increase rapidly. Now EC is considered not only as communication method but also as new economical activities. EC is a kind of new commerce model which uses electronic means. And EC has global characteristics so that many country's legislation which regulates it differently makes an obstacle to vital of EC. The purpose of this study is to examine legal problems of internet electronic commerce. First, there are some legal problems whether electronic document has same legal function like traditional documents. Second, electronic signature must has authenticity, integrity, non-repudiation, writing and confidentiality in order to use looks like common signature. Finally, electronic contract is concluded on principle of mutual agreement. It is apparent that the concept of arrival is applied to the date and place in conclusion of electronic contract.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.872-878
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• 2009

Passenger safety is a primary concern of the railway system. However, dozens of people are killed every year when they accidently fall on to the track from the boarding platform. This is one of the most urgent issues to solve regarding the railway platform. The installation environment, and the blind area problems as well as maintenance and operating costs which are not efficient have to be looked at. To solve these problems, we propose a 3D laser radar sensor based monitoring system for the railway platform. This paper introduces an overview, the detecting method, and the interface with the signalling system in detecting a fallen passenger from the platform using the 3D laser radar sensor.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.46
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• pp.181-210
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• 2010

The continuing advance of multimodal transport with the importance for efficient and effective logistics management emphasizes the need for uniform legal approach to international multimodal transport. However, the current fragmented instrument regulating such transport is being an obstacle to development of multimodal transport as it aggravates confusion and uncertainty. The Rotterdam rules, which was adopted in December 2008 by UNCITRAL, expands its scope of application to door-to-door transport. However, the new rules has some problems in its application to multimodal transport operation as it has been conceived not to regulate general multimodal carriage but to regulate contract of carriage by sea that extends its services to the transport by other modes. This article examines conflict of conventions in the Rotterdam Rules. The applicability of the Rotterdam Rules in international multimodal transport contract and possibility of potential conflict with other transport conventions are analyzed with some hypothetical cases. Furthermore, problems arising from application of the Rotterdam Rules under international multimodal transport Contracts are indicated in the chapter IV.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.527-532
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• 2005

The construction industries are facing problems of productivity, quality of work, safety, and the completion of projects in time. In construction industry a worker is exposed to hazardous environment, and has to do more physical work, effecting his health and also productivity. The automation and robotics can offer solution to many problems of the industry. In the past the major barrier to construction automation is the lack of electronic components and systems. This is solved now with the development of information technology, and the current obstacle is the high cost of automated systems, shortage of public money for R&D, and problems of acceptance. The robots employed in construction have followed the same concept as those employed in manufacturing. However, construction industry requires a different kind of robot compared to manufacturing Industry. The robots are stationery and product moves along the assembly line in manufacturing sector, but construction robots have to move about the site because buildings are stationary and of large size. The construction robots must function in adverse weather conditions, including variation in humidity, and temperature and increase the overall construction productivity rate. The major objective of the paper is to review the existing applications of building robots and to assess their implementation in building industry. A case study is considered for the implementation of robots for the painting work of the University Building at Saifabad PG College of Science, Hyderabad, India.

• Journal of Digital Convergence
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• v.17 no.3
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• pp.181-189
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• 2019

The purpose of this study is to derive obstacle factors to 'high value vocational training' and to suggest development strategies. The training aims to solve the quantitative and qualitative problems of female employment by providing professional training in high value areas such as ICT, SW and knowledge service. To verify the training to meet these objectives, 48 processes operated in 2018 were analyzed and field monitoring was conducted. As a result of the analysis, problems were identified and improvements were derived in terms of learners management, training course design, field practice operation, and performance evaluation. Based on these results, researchers suggested four ways to develop high value vocational training. First, select learners based on combined talent and second, strengthen the project of linking enterprises and structured field practices. Third, establish a performance evaluation system of its own and manage performance and fourth, expand support for excellent training courses and provide consulting for course development. The results of this study are expected to be used as a reference for establishing policies for high value occupational training. In the future, quantitative research should be conducted to clarify the performance and problems.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.26
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• pp.3-34
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• 2005

This thesis is in focus on keeping int'l businessman in mind application of CISG to perform smoothly in the their oversea's trade in accordance with taking effect on ratification of it from first, March, 2005. First of all, they have to keep in mind that it is possible to fall within the sphere of application of CISG of their contracts made between parties whose places of business are in different countries or although they have their places of business in different contracting states, if rules of private int'l law imply or express to the application of law of contracting state. Therefore in order to avoid confusion about whether apply or not, it is necessary to customize application of CISG as a proper law of their contracts. If so, they can avoid problem of requirements as to forms and any other requirement as to forms. Secondly they must attend the use of the legislative history of CISG and the use of the int'l case law and various scholarly thesises that studied on CISG such as information of Institute of Int'l Commercial Law under School of Law, PACE University. If so, problems which can give a rise in connection with interpretation of a basic and important terminology of CISG will be successfully conquest. In addition to above mentioned attentiveness, they must keeping in mind that various problems in connection with application of provisions of CISG can give their oversea's business a obstacle. buy the way of precaution against this case, they have to collect and analyze various materials about CISG.