• Journal of the Korea Institute of Building Construction
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• v.11 no.6
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• pp.567-575
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• 2011

With the development of construction information, a computerization tool for architectural process control is a necessary tool. However, the reality is that the conditions and understanding of users are not sufficient to fully utilize such a tool. In particular, it was analyzed that the reason for the negative feedback from hands-on workers regarding the current process control information system is that there is a difficulty in accessing the system for users that are not process and planning experts, due to a lack of information and technical contents at the phase of control and planning prior to the process plan. Therefore, the demands of users and a direction for the improvement of a system in terms of optimizing process control computerization were investigated, with the aim of addressing the disadvantages of the existing system and developing a professional system that is specialized in the construction industry. Therefore, it is necessary to construct an integrated WBS (IWBS) that combines WBS with CBS, and subsequently, it is judged that the most important aspect is the integrated technology of compatibility and operation of data that is linked with OBS. The process information must then deal with the changing information; in other words, the amount of construction, construction cost, and the required construction period etc., by coding data into a 4-unit index, such as a project unit (WBS Level 1), a project facility unit (WBS Level 2), a management department unit (OBS Level 1), and a control manager unit (OBS Level 2). After that, it was found that it is necessary to develop a computer system to consistently integrate process information into a management department.

• Proceedings of the IEEK Conference
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• 2000.06b
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• pp.32-35
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• 2000

Oxide-nitride-oxide(ONO) structures were formed by sequential radio frequency reactive magnetron sputtering method. The chemical composition and structure of these films were studied by using of secondary ion mass spectroscopy(SIMS) and Auger electron spectroscopy(AES) SIMS and AES experiments show the existence of nitridation at the SiO$_2$/Si substrate. The electrical characteristics of ONO films were evaluated by I-V and high frequency C-V measurements When the ONO films were annealed at 90$0^{\circ}C$ for 30 sec in $N_2$ ambient, the breakdown voltage increased and flat-band voltage decreased under high electric field.

• JSTS:Journal of Semiconductor Technology and Science
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• v.17 no.3
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• pp.354-362
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• 2017

We investigated the improvement in electrical characteristics of large AlGaN/GaN on Si Schottky barrier diode (SBD) induced by structural change to achieve a better trade-off between the forward and reverse performance to obtain high power conversion efficiency in PFC converter. Using an optimized dry etch condition for a large device, we fabricated three-types of SBD with 63 mm channel width: conventional, recessed, recessed dual-anode-metal SBD. The recessed dual-anode-metal SBD exhibited a very low turn-on voltage of 0.34 V, a high forward current of 1.63 A at 1.5 V, a leakage current of $114{\mu}A$ at -15 V, a breakdown voltage of 794 V.

• Journal of the Korean Vacuum Society
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• v.16 no.6
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• pp.414-423
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• 2007

Field Emission Display(FED) has significant advantages over existing display technologies, particularly in the area of small and high quality display. In order to test the feasibility of fabricating the System-on-Chip(SOC) with FED, we conducted the experiment to use the p-n junction as an electron beam source for the flat panel display. A novel structure was constructed to form p-n junctions by generating inversion layer with the electric field from the cantilever style gate. When we applied more than 220V at the cantilever style gate which has a height of $1{\mu}m$, avalanche breakdown onset was successfully achieved. The characteristics was compared with the electron emission from the ultra shallow junction in the avalanche region. The experiment result and the future direction were discussed.

• Korean Journal of Construction Engineering and Management
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• v.12 no.3
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• pp.3-10
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• 2011

Currently, technologies for industrialization and dissemination for Han-Ok are developed actively. Also BIM technologies are actively developed. However, it is difficult to find the research and study cases for construction method and process for Han-Ok. BIM is the technology for managing information with element as a unit for building design, construction and management, and it is closely related to Han-Ok using assembling method for building construction. We analyzed the basic construction processes for IK-Gong and MinDoRi house, typical types of Han-Ok. Also we developed the Work Breakdown Structure of construction process for Han-Ok and suggested the method for construction simulation using BIM. Simple BIM model of Han-Ok which is Ik-Gong type is used for case study. It was possible to link automatically between 3D elements objects and construction activities about 95% in the case study. More studies of construction method for various type of Han-Ok and rules for link between elements and construction activities are required for Industrialization and dissemination of Han-Ok.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.9
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• pp.1606-1611
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• 2008

Recently, The diagnosis techniques of electric facilities are developed on live line. This paper describes the discharge characteristics of polymer insulator(EPDM A type). Keeping the facilities in good working order, the goal of this paper will provide the information to enable user to easily judge conditions of facilities on the spot. The performance of polymer insulator is assessed from the KS C IEC 60270 and CEA LWIWG-01(96)(Tracking Wheel Test). As the results, UV generation patterns of polymer insulator grow like a jellyfish shape follow the ramping voltage. Discharging UVs are detected at about 31.25% of breakdown voltage. Just then, dimension of UV image is about $0.84cm^{2}$. The dimension of max. UV image is about $297.4cm^{2}$ at $160kV(V_{bd})$. The position of UV generation due to surface discharge of polymer insulator is the center of insulator in the early, then moved the ground side and the last, UV image moved through the junction part of source side. Surface of aged polymer insulator is cracked and faded due to arc. UV absorption spectrum of polymer insulator are appeared the C-H bond of scissoring vib. at $1014cm^{-1}$ and C=O bond of recombination structure. Also, recombined UV absorption peak such as C-H, N-H, and O-H is detected at the $3321cm^{-1}$. Through the paper, there are inspection data which are the relations between surface discharge of polymer insulator and UV detecting image.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.1
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• pp.1-7
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• 2014

A bidirectional transient voltage suppression (TVS) diode consisting of specially designed $p^--n^{{+}+}-p^-$ multi-junctions was developed using low temperature (LT) epitaxy and fabrication processes. Its electrostatic discharge (ESD) performance was investigated using I-V, C-V, and various ESD tests including the human body model (HBM), machine model (MM) and IEC 61000-4-2 (IEC) analysis. The symmetrical structure with very sharp and uniform bidirectional multi-junctions yields good symmetrical I-V behavior over a wide range of operating temperature of 300 K-450 K and low capacitance as 6.9 pF at 1 MHz. In addition, a very thin and heavily doped $n^{{+}+}$ layer enabled I-V curves steep rise after breakdown without snapback phenomenon, then resulted in small dynamic resistance as $0.2{\Omega}$, and leakage current completely suppressed down to pA. Manufactured bidirectional TVS diodes were capable of withstanding ${\pm}4.0$ kV of MM and ${\pm}14$ kV of IEC, and exceeding ${\pm}8$ kV of HBM, while maintaining reliable I-V characteristics. Such an excellent ESD performance of low capacitance and dynamic resistance is attributed to the abruptness and very unique profiles designed very precisely in $p^--n^{{+}+}-p^-$ multi-junctions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.157-163
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• 2016

BIM is currently applied in some domestic construction firms, but it is not being actively utilized due to changes in working environments and qualms about new studies. In order to utilize a BIM model in the design phase, process information is needed during construction, but the input system and utilization method of the process information's state are not complete. Therefore, we propose a BIM template for construction progress management that can show basic BIM information as the construction progresses in an easy and convenient way. This method will facilitate the adoption of BIM and enhance the productivity of construction companies. To this end, we designed a progress explorer for step-by-step progress and work schedules, and we generated three-dimensional views and a progress list by applying unit information (primary units, part units, and detail units) of the work breakdown structure (WBS) to the parameters. To use the BIM template, work progress information is input to the BIM modeling objects through Dynamo. We also used Dynamo for quick and easy calculation of the quantity of materials needed for construction work. To test the BIM template, we applied it to an actual project and evaluated its visibility and a progress list. The results showed that the proposed BIM template facilitates progress management of a project and can thus facilitate the adoption of BIM and improve the productivity of construction companies.

• Korean Journal of Construction Engineering and Management
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• v.17 no.2
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• pp.99-109
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• 2016

The utilization of Building Information Modeling (BIM) has increased in order to enhance the integration of information for management and resources throughout the construction projects. Therefore, various BIM softwares have been used under open BIM environments in the building and plant construction industry. However, it has obstructive factors due to the lack of interoperability. In order to address this problem, this study conducted an interoperability analysis of BIM software focused on user-defined properties for enhanced function and efficiency. Result of the analysis shows that authoring tools have more interoperability problems than viewer tools and simulation tools have. In terms of interoperability, user-defined properties outperforms than those of system basic properties and logic data. Therefore, it was found that functional improvement and workload minimization in BIM can be attained by applying the GBS (an user-defined property for automatic manipulation of BIM proposed by Jung et al. 2013) that enables automatic link between geometric data and non-geometric data. In this respect, this study concludes that the application of user-defined property (e.g. GBS) can be an effective method for information integration throughout construction projects.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.137-142
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• 2003

Construction CALS has been introduced with an aim to improve the effectiveness of construction management in the public sector. The objective of this paper is to provide an approach to implementing an integrated construction management environment. The environment described in this paper provides a methods for the owner and the contractor as well as designers and engineers to interact in a sing control scheme. This interaction represents the collaboration between the contractual parties for sharing construction information. XML technology has been applied as a basic technology for delivering data in the system. The XML-based forms are loaded on the system, whose data are stored in the central database right after review and approval. In future the integrated construction management environment can be further developed to the extend that the contractor's information system is directly interface with the owner's.