• Korean Journal of Construction Engineering and Management
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• v.23 no.6
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• pp.101-110
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• 2022

Recently, the global construction market is expected to grow at an annual average of 4.8% by 2025 and the risk of overseas construction is also expected to increase accordingly. In particular, domestic construction companies intensively participated in the EPC(Engineering, Procurement, Construction)/Turnkey project, but as a result of failing to respond to contractual risks, they have suffered losses of trillions of won in overseas business since 2013. Nevertheless, there have been not many studies on the derivation of EPC/Turnkey's contractual key risk sub-clauses. Therefore, in this study, the key risk sub-clauses were studied for the conditions of the 2017 Silver Book contract issued by the International Consulting Engineering Federation(FIDIC). To this end, 30 experts with more than 10 years of experience in international construction contracts were formed as a panel to conduct a Delphi survey on 170 sub-clauses of 21 clauses of FIDIC Silver Book to derive 62 main risk sub-clauses. In addition, the RPN(Risk Priority Number) was finally calculated using the FMEA(Failure Mode and Effect Analysis) technique, and 25 key risk sub-clauses within the Critical Risk range were derived. Through the results of this study, the practical point of view is able to refer to the contract provisions to be carefully reviewed at the bidding and contract signing stage in overseas construction projects. From an academic point of view, it provides direction and basic knowledge of how to study the contract fields used in overseas construction EPC/Turnkey projects.

• The Journal of the Korea Contents Association
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• v.13 no.2
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• pp.127-136
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• 2013

The purpose of this study is to derive key success factors' priorities to industrialize can art using AHP methodology and to suggest blue ocean strategy of can art. First, the survey result showed that the most important factor was eco-commercialization(0.227). And cultural value(0.223), distribution(0.217), experience learning(0.202) are presented in order in terms of the importance. Second, it also suggested eco-design(0.118), recycling improvement(0.118), education value increase(0.117), viral marketing(0.113), and various experience learning(0.105) as detailed important factors. Moreover, this study implies that can art needs to focus on intensifying environmental craft education and eco-commercialization as blue ocean strategies.

• Journal of Power Electronics
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• v.16 no.2
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• pp.631-642
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• 2016

Usually, the output characteristics of a photovoltaic (PV) array are significantly affected by non-uniform irradiance which is caused by ambient obstacles, clouds, orientations, tilts, etc. Some local maximum power points (LMPP) in the current-voltage (I-V) curves of a PV array can result in power losses of the array. However, the output power at the global maximum power point (GMPP) is different in different interconnection schemes in a PV array. Therefore, based on the theoretical analysis and mathematical derivation of different topological structures of a PV array, this paper investigated the output characteristics of dual series PV arrays with different interconnections. The proposed mathematical models were also validated by experimental results. Finally, this paper also concluded that in terms of performance, the total cross tied (TCT) interconnection was not always the optimal structure, especially in a dual series PV array. When one of the PV modules was severely mismatched, the TCT worked worse than the series parallel (SP) structure. This research can provide guidance for switching the interconnection to gain the greatest energy yield in a changeable- structure PV system.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.6
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• pp.931-946
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• 2018

In line with the increased usability of utility pipe conduits in urban areas, construction and R&D activities of utility tunnel, incorporated with the shield TBM method, are actively under way. The utility tunnels are installed through underground excavation, and thus are relatively weak in terms of construction safety. However, hazards associated with the utility tunnel construction have not been properly identified, despite the introduction of a policy to the 'Design for Safety' for the purpose of reducing accident rates in the construction industry. Therefore, in this study, following the derivation of hazards associated with utility tunnel, these hazards were then used as the basis to uncover key safety hazards requiring extensive management in a field, which were then used to conduct a risk assessment having applied the matrix method so that the results can be utilized in risk assessment during the stages of utility tunnel planning, design, and construction, while also serving as a data reference.

• Earthquakes and Structures
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• v.15 no.1
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• pp.67-79
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• 2018

Malaysia and Singapore have adopted Eurocode 8 (EC8) for the seismic design of building structures. The authors studied the seismic hazard modelling of the region surrounding Malaysia and Singapore for a long time and have been key contributors to the drafting of the Malaysia National Annex (NA). The purpose of this paper is to explain the principles underlying the derivation of the elastic response spectrum model for Malaysia (Peninsular Malaysia, Sarawak and Sabah). The current EC8 NA for Singapore is primarily intended to address the distant hazards from Sumatra and is not intended to provide coverage for potential local intraplate hazards. Hence, this paper recommends a reconciled elastic response spectrum for Singapore, aiming to achieve a more robust level of safety. The topics covered include the modelling of distant interplate earthquakes generated offshore and local earthquakes in an intraplate tectonic setting, decisions on zoning, modelling of earthquake recurrences, ground motion and response spectrum. Alternative expression for response spectrum on rock, strictly based on the rigid framework of EC8 is discussed.

• Journal of Environmental Science International
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• v.2 no.3
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• pp.193-199
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• 1993

This study has two objectives. One is developing the runoff model for Hoe-Dong Reservoir basin located at the upstream of Su-Young River in Pusan. To develop the runoff model, basic hydrological parameters - curve number to find effective rainfall, and storage coefficient, etc. - should be estimated. In this study, the effective rainfall was calculated by the SCS method, and the storage coefficient used in the Clark watershed routing was cited from the report of P.E.B. The other is the derivation of transfer function for Hoe-Dong Reservoir basin. The linear, discrete, input-output model which contained six parameters was selected, and the parameters were estimated by the least square method and the correlation function method, respectively. Throughout this study, rainfall and flood discharge data were based on the field observation in 1981.8.22 - 8.23 (typhoon Gladys). It was observed that the Clark watershed routing regenerated the flood hydrograph of typhoon Gladys very well, and this fact showed that the estimated hydrological parameters were relatively correct. Also, the calculated hydrograph by the linear, discrete, input-output model showed good agreement with the regenerated hydrograph at Hoe-Dong Dam site, so this model can be applicable to other small urban areas. Key Words : runoff, effective rainfall, SCS method, clark watershed iou상ng, hydrological parameters, parameter estimation, least square method, correlation function method, input-output model, typhoon gladys.

• ETRI Journal
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• v.29 no.6
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• pp.755-768
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• 2007

A very promising application of active RFID systems is the electronic seal, an electronic device to guarantee the authenticity and integrity of freight containers. To provide freight containers with a high level of tamper resistance, the security of electronic seals must be ensured. In this paper, we present the design and implementation of an electronic seal protection system. First, we propose the eSeal Protection Protocol (ePP). Next, we implement and evaluate various cryptographic primitives as building blocks for our protocol. Our experimental results show that AES-CBC-MAC achieves the best performance among various schemes for message authentication and session key derivation. Finally, we implement a new electronic seal system equipped with ePP, and evaluate its performance using a real-world platform. Our evaluation shows that ePP guarantees a sufficient performance over an ARM9-based interrogator.

• The KIPS Transactions:PartC
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• v.11C no.6 s.95
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• pp.739-746
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• 2004

License mechanisms are the key elements in almost all DRM(digital rights management) systems. The license mechanisms are designed for the clear identification and enforcement of contents, principals, and usage rules in DRM systems. But current license mechanisms are lacking in the flexibility for the secure and efficient sharing of the contents among the members of a group such as a family or a part of an enterprise. This paper suggests a new license mechanism for efficient and secure sharing of contents in DRM systems among the members of a group. We named it member/group license mechanism. The mechanism extends the current license mechanisms by introducing new concepts such as group licenses, member licenses, and derivation relationships between licenses.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.4
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• pp.863-868
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• 2013

In recently years, many digital logic systems based on graph theory are analyzed and synthesized. This paper presented a method of constructing the function using edge valued extension graph which is based on graph theory. The graph is applied to a new data structure. from binary graph which is recently used in constructing the digital logic systems based on the graph theory. We discuss the mathematical background of literal and reed-muller expansion, and we discuss the edge valued extension graph which is the key of this paper. Also, we propose the algorithms which is the function derivation based on the proposed edge valued extension graph. That is the function minimization method of the n-variables m-valued functions and showed that the algorithm had the regularity with module by which the same blocks were made concerning about the schematic property of the proposed algorithm.

• Korean Journal of Remote Sensing
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• v.28 no.6
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• pp.693-704
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• 2012

Space-born remote sensing camera systems tend to be developed to have very high performances. They are developed to provide extremely small ground sample distance, wide swath width, and good MTF (Modulation Transfer Function) at the expense of big volume, massive weight, and big power consumption. Therefore, the camera system occupies relatively big portion of the satellite bus from the point of mass and volume. However, the camera systems for lunar exploration don't need to have such high performances. Instead, it should be versatile for various usages under various operating environments. It should be light and small and should consume small power. In order to be used for national program of lunar exploration, electro-optical versatile camera system, called MAEPLE (Multi-Application Electro-Optical Payload for Lunar Exploration), has been designed after the derivation of camera system requirements. A ground model of the camera system has been manufactured to identify and secure relevant key technologies. The ground model was mounted on an aircraft and checked if the basic design concept would be valid and versatile functions implemented on the camera system would worked properly. In this paper, results of design and functional test performed with the field campaigns and air-born imaging are introduced.