• Smart Structures and Systems
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• v.31 no.3
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• pp.283-299
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• 2023

Structural stability of floating platforms has long since been a crucial issue in the field of marine engineering. Excessive motions would not only deteriorate the operating conditions but also seriously impact the safety, service life, and production efficiency. In recent decades, several control devices have been proposed to reduce unwanted motions, and an attractive one is the tuned heave plate (THP). However, the THP system may reduce or even lose its effectiveness when it is mistuned due to the shift of dominant wave frequency. In the present study, a novel adaptive tuned heave plate (ATHP) is proposed based on inerter by adjusting its inertance, which allows to overcome the limitation of the conventional THP and realize adaptations to the dominant wave frequencies in real time. Specifically, the analytical model of a representative semisubmersible platform (SSP) equipped with an ATHP is created, and the equations of motion are formulated accordingly. Two optimization strategies (i.e., J₁ and J₂ optimizations) are developed to determine the optimum design parameters of ATHP. The control effectiveness of the optimized ATHP is then examined in the frequency domain by comparing to those without control and controlled by the conventional THP. Moreover, parametric analyses are systematically performed to evaluate the influences of the pre-specified frequency ratio, damping ratio, heave plate sizes, peak periods and wave heights on the performance of ATHP. Furthermore, a Simulink model is also developed to examine the control performance of ATHP in the time domain. It is demonstrated that the proposed ATHP could adaptively adjust the optimum inertance-to-mass ratio by tracking the dominant wave frequencies in real time, and the proposed system shows better control performance than the conventional THP.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.2D
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• pp.259-267
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• 2008

Nowadays PMIS (Project Management Information System) based on web is widely applied to communication, collaboration and community in construction jobsite for various organization such as subcontractors, general contractor, engineering company, supervisors and client. However, individual PMIS in jobsite is prone to be troublesome issue for integration and exchange of information regarding project management in corporate and may result in conflict of data application. The main reason should be lack of information strategy plan such as company master plan for information. This research shows a critical success factor that a big construction company of Korea establishes procedure and method for information strategy plan. In addition, It is to suggest how to be implemented PMIS architecture and execute business process innovation in corporate level. This research expects contribution that many construction companies reduce mistakes to be implemented management information system and to optimize system in corporate level.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3D
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• pp.417-422
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• 2008

With standard orthorectification algorithms, one can produce unacceptable structure duplication in the orthophoto due to the double projection. Because of the abrupt height differences, such structure duplication is a frequently occurred phenomenon in the dense urban area which includes multi-history buildings. Therefore, occlusion area detection especially for the urban area is a critical issue in generation of true orthophoto. This paper deals with occlusion area detection with visible height based approach from aerial imagery and LiDAR. In order to accomplish this, a grid format DSM is produced from the point clouds of LiDAR. Next, visible height based algorithm is proposed to detect the occlusion area for each camera exposure station with DSM. Finally, generation of true orthophoto is presented with DSM and previously produced occlusion maps. The proposed algorithms are applied in the Purdue campus, Indiana, USA.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5D
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• pp.587-595
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• 2008

Many studies on bus scheduling optimization have been done from the 1960s to recent years for establishing rational bus schedule plan that can improve convenience of bus passengers and minimize unnecessary runs. After 2000, as part of the Intelligent Transport Systems (ITS), the importance of the schedule management and providing schedule information through bus schedule optimization has become a big issue, and much research is being done to develop optimization models that will increase bus passenger convenience and, on the side of bus management, minimize unnecessary bus operation. The purpose of this study is to calculate the optimal bus frequency and create a timetable for each bus stop by applying DTR or DTRC model that use data for each bus stop and route segment. Model verification process was implemented using data collected from bus management system (BMS) and integrated transit-fare card system for bus route of Seoul's No. 472 line. In order to evaluate the reliability and uncertainty of optimal solution, sensitivity analysis was implemented for the various parameters and assumptions used in the bus scheduling model.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5D
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• pp.609-615
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• 2008

A Pedestrian Space in the transit transfer center is compositively made of a variety of activities for pedestrians. The pedestrians avoid access to the transit transfer center and the revitalization of the transit transfer center is obstructed as the travel cost of the pedestrians increases. This study provides the pedestrians using the transit transfer center with the significant real-time routing service and helps the movement of pedestrians to minimize the economical loss considering the travel cost and congestion of the pedestrians in the transit transfer center. In this paper, we propose a solution to construct a spatial map for the pedestrians in the transit transfer center to receive the significant real-time routing service based on Ubiquitous technique which is big issue around the world.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.1D
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• pp.81-89
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• 2009

CM(Configuration Management) is a field of management that focuses on establishing and maintaining consistency of a product's performance and its functional and physical attributes with its requirements, design, and operational information throughout its life. Recently upcoming concept of CM, regardless of various definitions, consists of the organization and the process for value creation through project change management, value preservation by Risk, Project Management implementation by Change management. The CM provide a basis for, and a record of, the project's performance in meeting the scope, time, cost. Overseas international companies have already adopted the CM system and enjoyed the benefits arising from such systems. And the CM provides perspectives and insights applicable to all types of projects. This study presents the review on the current systems now in use at jobsites and known to be efficient, and the introduction and application of configuration systems now at big issue. Hereby indicates the connective system consisted of work process, change control and knowledge referring to the methods and actual cases as an effective promotion of CM.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.4D
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• pp.331-338
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• 2010

In the case of Korea, research on traffic management is insufficient to cover the increasing incidence of disaster. Furthermore, many of the traffic management manual does not touch up on how to administer/manage in case of disaster, except for the one made by 'Korea Expressway Corporation.' In response to this issue, this research is based on a thesis to establish concept of guideline for traffic management in the case of an disaster. In order to achieve this goal, there has been an analysis of the American's manual, molded and changed to be Korea-specific. In the future, based on the u-T circumstances are established, traffic management will become much more efficient. This paper presents important details and ways of management for each step of an disaster event: prevention, preparation, response and restoration.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.3D
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• pp.357-362
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• 2009

The Investment to road projects has been a hot issue in the aspect of its possible overlapping or overinvestment in Korea. Therefore, additional road construction is not always accepted in these days. This paper investigated several indices including the country index and the road-extension rate index as well as a newly developed index for identifying and comparing road stocks among the OECD countries. Furthermore, the study has estimated some reasonable amount of additional road stocks of Korea when its GDP becomes twenty thousands per capita to forty thousands per capita in future by comparing the amount of stacks of OECD countries at those times. The result can be used for setting the target of road stocks in practical manner in the absence of the universally accepted theory in the road stock provision arena.

• International Journal of Computer Science & Network Security
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• v.23 no.7
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• pp.79-90
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• 2023

Leadership development corresponds to the focus on the individual's success and competitiveness strategy. This is the optimal direction of the organization of attitude development because it covers two aspects of the student's personality development, professionally-oriented and self-centric. The aim of the study is to identify and compare the leadership level in second-and fourth-year students to see dynamics of development and implementation of the leadership phenomenon in the professional and personal making up of future specialists. Based on the theoretical analysis of the issue, the authors developed an objective and subjective diagnostic model for leadership skills. In this study, data of the objective diagnostic technique are the key. Subjective diagnostic technique for leadership skills provides insights for problem interpretation. At the level of the first group of respondents, the average Leadership Skills Level of the second-year students was quite low and was found within the medium level. The second group of respondents consisting of the fourth-year students showed a slight but effective improvement. The Leadership Skills of this group were found at a sufficient level. Positive dynamics was revealed for all criteria of leadership skills as a result of applying objective diagnostic methods: decreased percentage of students with negative and relatively low markers of Leadership Skills Level and corresponding increase in percentage of applicants with positive markers of Leadership Skills Level. Further research can be organized in the direction of identifying and developing successful universal and professionally-oriented tactics for leadership development in students as part of attitude development.

• Journal of Appropriate Technology
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• v.4 no.2
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• pp.96-107
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• 2018

Korea is the only country which had been helped from developed countries and is now helping developing countries. Various ODA programs have been actively conducted by Korea after joining the OECD in 1999. Recently, Korea increases the ODA funds to achieve the goal of ODA/GNI ratio 0.2% until 2020. Science and technology ODA (so called appropriate technology) is a huge issue because the departments or agencies of Korean government also increase ODA funds. This research will provide the information of Korean science and technology ODA according to the research areas and funding sources since 1999.