• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.223-232
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• 2002

The government, in order to settle and activate the use of Construction Management (CM) method, clarified the legal Issues pertaining to infrastructure development and is taking an active role to promote CM through government sponsored pilot projects. However, when a CM method is applied to a turn-key protect, many applicational difficulites are expected. With design and construction are performed under the simple responsibility in a turn-key method, roles of CM's is overlapped. Also, the characteristics of turn-key method are not reflected to the present $\lceil$CM Work Guideline$\rfloor$. Over the years, various problems have been identified from turn-key projects. Korea's $\lceil$CM Work Guideline$\rfloor$ is more inclusive compared to the CM services of CMAA and overlooks the importance of CM's roles in pre-design phase. In this study, CM's roles of pre-construction phase (pre-bidding, bidding, detail design, contracting) in construction turn-key projects were identified and complementary policy for institution was suggested. We further look into dividing the roles of the CM at turn-key project Into professional role and emotional role. Also, we speculate problems of the existing experience in turn-key projects and suggest a rough methodology on how these concepts can be adjusted for improve the turn-key method.

• Journal of the Korean Society of Systems Engineering
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• v.10 no.2
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• pp.59-69
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• 2014

In the bidding stage of turn-key based plant construction contracts, owners provide design and performance basis for contractors instead of giving design drawing. To win the bid for a plant construction, the contractors should be obliged to satisfy and ensure owners'requirements such as design and performance basis in a plant construction project, In other words, owners imposes technical risk of the design to the contractors by specifying responsibility for the analysis and verification of the plant construction. Thus, it is very important that contracters make accurate and realistic basic design plan in a short period of time. To deal with such a situation, we propose a systems engineering approach for the analysis and management of the technical risk. Specifically, we first: 1) Analyzes technical risk related with the plant design information for the bidders, followed by 2) Developing stakeholder requirements for the basic engineering design, and 3) System requirements for dealing with technical risk. Also, in this paper, we proposed converting method from MOE(Measure of Effectiveness) to MOP(Measure of Performance) in the risk analysis. To show the effectiveness of the proposed method, we carried out a case study.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.6
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• pp.21-33
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• 2005

This study aims to find out actual conditions of environmental-friendly design on outdoor space of housing estate, and then to propose the direction of environmental-friendly design in order to construct the adequate environmental-friendly housing estates. First of all, this study investigated the environmental-friendly design elements on outdoor space of housing estates through literature survey and selected 9 major elements based on the result of the investigation. And then 15 KNHC housing estates were analyzed to find out design actualities of environmental-friendly elements. Major results of this study are as follows. 1) The environmental-friendly design elements were highly adopted in outdoor space of housing estates. The adoption rate of environmental-friendly design elements is 81.0% in average. But, 5 major elements were passively adopted out of 9. 2) According to the comparative analysis of KNHC housing estates, The adoption rate of environmental-friendly design elements was similar in metropolitan housing estates and non-metropolitan housing estates. But, the adoption level of environmental-friendly design element in metropolitan housing estates was higher than one in non-metropolitan. It shows that metropolitan housing estates are more activly adopted in 6 major elements. 3) According to the comparative analysis of design method of KNHC housing estates, The adoption rate and the adoption level of environmental-friendly design elements by turn-key design method and competition design method were higher than by general design. It shows that the housing estates designed by turn-key and competition design method are more activly adopted in 7 major elements.

• Korean Journal of Construction Engineering and Management
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• v.13 no.3
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• pp.122-130
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• 2012

Currently, TK(Turn-key) projects have been implemented, the projects on TK basis still have shown several problems rather than its own merits as a bidding method. Increasing the number of claims being occurred during construction process of the projects is reality because of unclear notice of tender documents and conditions of the contract, design review system, and decision process of the qualified bidder. To establish desirable TK projects in domestic market, not only should resonable alternatives for carrying out design review system and selecting the bid winner be set up, but also proper standards for reforming irrational system of contract, bid, and notice of tender related to TK projects. This study is intended to reduce the number of claims and implement efficient projects of apartment construction on TK basis by identifying potential problems through analysis of claim examples of TK projects which have difficulties of revising contract agreement such as drawings and suggesting improvement methods for contract conditions and notice of tender docuements.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.258-259
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• 2013

Recently, architectural design has been changing from formal design to freeform design due to the digitalization of construction industry. Especially, the formal design has been accepted as a design trend recently and applied many times as a design concept in the architectural design competitions such as turn-key. However, various deflects such as water leak and cracks have been occurred because the traditional construction methods had been applied without any revision or adaptation of the formal construction method for the freeform building construction. Therefore this research proposes location point control method for freeform metal panel installation which is focused on the application of LH JinJu new office.

• Journal of architectural history
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• v.15 no.1 s.45
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• pp.7-27
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• 2006

This study aims to identify and analyze the factors that influenced the construction of London Eye which was led by private groups, including characteristics in progress, differentiated value in design, the combination of technology and design, and construction costs. The results of this study were the followings. 1) London Eye provides a new construction method for a landmark in the downtown in that the architects became the clients of the project which might have been hoarded, procuring the construction costs and completing it by themselves. 2) London Eye presents a space utilization method where undeveloped spaces in the downtown are used in three-dimensions by erecting a structure on the river with a minimum land. 3) The process of design, production and erection is propelled the realization of technical intention design with one system and from at the initial stage, the participation of the engineer where the designer is equal with you must accompany. 4) London Eye is endowed with strong shape by a circle in design concept, which is the simplest geometrical figure, and it provides organic relationship between the past and the present by utilizing historical elements in various ways. 5) The construction was completed through four phases including idea phase, promotion phase, turn-key contract phase, and design-build phase. The most critical factor to the success is derived from the direct contact with Involved companies from the production phase. 6) In a project facing many challenges in terms of technology, the design-build method proves to be a more effective method than turn-key contract in that it may more allocate risks and enable coherent implementation of the core concept in design. The organization for the design-build method was composed of three phases including general affairs, responsible contracting by sector, and cooperative system by sector. Since that was a new concept structure, high-level contractors who hadn't had existing cooperative relationships with one another formed new cooperative relationship, while collaborating companies who had long cooperated led the responsible contracting and sub-cooperative system, which resulted in reduction of risks and time. 7) The major factors to change design were the design characteristics, derived from a technically great combination, and the opening time. 8) A new erection method was applied to London Eye, a structure that overcame the limitation in land and period, and the process of installation demonstrated that it is an important value for the construction of a landmark in the city. 9) In spite of many visitors and tremendous operational income, the factors that London Eye fails to free itself from debts include the construction costs expended double than expected, and interest burden to the investments, which occurred in the course of procuring the costs. Absolute limit in time increased the construction costs, resulting in being a great obstacle in the course of operation.

• Journal of Power Electronics
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• v.15 no.1
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• pp.146-159
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• 2015

Since the power capacity needed for the propulsion of large ships is very large, a multiphase AC induction propulsion mode is generally adopted to meet the higher requirements of reliability, redundancy and maintainability. This paper gives a detailed description of the development of a 20MW fifteen-phase PWM driver for advanced fifteen-phase propulsion induction motors with a special third-harmonic injection in terms of the main circuit hardware, control system design, experiments, etc. The adoption of the modular design method for the main circuit hardware design can make the enclosed mechanical structure simple and maintainable. It can also avoid the larger switch stresses caused by the multiple turn on of the IGBTs in conventional large-capacity converter systems. The use of the distributed controller design method based on a high-speed fiber-optic ring net for the control system can overcome such disadvantages as the poor reliability and long maintenance times arising from the conventional centralized controller which is designed according to point-to-point communication. Finally, the performance of the 20MW PWM driver is verified by experimentation on a new fifteen-phase induction propulsion motor.

• Journal of Electrical Engineering and Technology
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• v.13 no.3
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• pp.1060-1068
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• 2018

Droop control schemes have been widely employed in the control strategies for Multi-Terminal Direct Current (MTDC) system for its high reliability. Under the conventional DC voltage-active power droop control, the droop slope applies a proportional relationship between DC voltage error and active power error for power sharing. Due to the existence of DC network impedance and renewable resource fluctuation, there is inevitably a DC voltage deviation from the droop characteristic, which in turn results in inaccurate control of converter's power. To tackle this issue, a piecewise droop control with DC voltage dead band or active power dead band is implemented into controller design. Besides, an advanced droop control scheme with versatile function is proposed, which enables the converter to regulate DC voltage and AC voltage, control active and reactive power, get participated into frequency control, and feed passive network. The effectiveness of the proposed control method has been verified by simulation results.

• Molecules and Cells
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• v.45 no.2
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• pp.76-83
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• 2022

Neurons-on-a-Chip technology has been developed to provide diverse in vitro neuro-tools to study neuritogenesis, synaptogensis, axon guidance, and network dynamics. The two core enabling technologies are soft-lithography and microelectrode array technology. Soft lithography technology made it possible to fabricate microstamps and microfluidic channel devices with a simple replica molding method in a biological laboratory and innovatively reduced the turn-around time from assay design to chip fabrication, facilitating various experimental designs. To control nerve cell behaviors at the single cell level via chemical cues, surface biofunctionalization methods and micropatterning techniques were developed. Microelectrode chip technology, which provides a functional readout by measuring the electrophysiological signals from individual neurons, has become a popular platform to investigate neural information processing in networks. Due to these key advances, it is possible to study the relationship between the network structure and functions, and they have opened a new era of neurobiology and will become standard tools in the near future.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2575-2582
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• 2013

In the delivery systems for public construction works, design-build methods such as turn-key and alternative have contributed to improving the quality of structures and developing the construction technology. However, it is pointed out that construction based on a design-build method is likely to waste a budget due to its higher contract price than construction based on a design-bid-build method. Other issues such as contract monopoly, bid rigging and deliberation irregularity in design-build. Since there are not much works have been accomplished to comparatively analyze the actual performance and effect based on delivery methods, discussing and judging the performance and effect of each deliver method with limited information could lead to an error. Thus, this study by extensively investigates the actual project cost data, ranging from contract price to the construction cost of the public construction works and comparatively analyzed the characteristics of each delivery method about cost structure and fluctuation trend. This work is expected to assist stake-holders in properly understanding delivery systems for public construction works and promoting their efficient management.