• Smart Structures and Systems
• /
• v.20 no.3
• /
• pp.343-350
• /
• 2017

An experimental study is presented of the application of fiber Bragg grating (FBG) interrogation method based on optical time-domain reflectometery (OTDR) to monitoring strain in bent reinforced concrete beams. The results obtained with the OTDR-based method are shown to agree well with the direct spectral measurements. Strain sensitivity, resolution and measurement range amounted to $0.0028dB/{\mu}strain$; $30{\mu}strain$; $4000{\mu}strain$, correspondingly. Significant differences are observed in surface and inner deformations of the test beams which can be attributed to different mechanical properties of concrete and steel reinforcement. The prospects of using OTDR-based FBG interrogation technique in real-life applications are discussed.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.52 no.7
• /
• pp.407-413
• /
• 2003

Before expanding of distribution automation application to distribution network, we must examine whether there are economical effect. Investment expense for distribution automation can be divided into facility investment expense, maintenance expense, communication expense, investment expense etc. Effect of distribution automation can classify by effect that can convert into money and effect that can not convert into money. Representative effect is outage time decrease effect, distribution line loss decrease effect, main transformer upload effect, distribution line upload effect, work environment improvement effect of lineman and so on. This paper studied economical effect and break-even Point for investment expense by using data that acquire in KEPCO's distribution network.

• Journal of Korean Association for Spatial Structures
• /
• v.13 no.1
• /
• pp.105-112
• /
• 2013

An automation of standardized rebar shop drawing is necessary for easy application by improving workability, prompt preparation to field change request and easy revisions of shop drawing. Through investigating problem of current rebar shop drawing, we found that standardization of reinforcing detail, standardization of rebar expression and automation of rebar shop drawing program for the sake of designer is needed. We will investigate disagreement of reinforcing detail between building code and how worker build structure for standardization of reinforcing detail, demands of companies participated in rebar process for standardization of rebar expression and proper algorithm with selectable level of inputting data for automation of rebar shop drawing program for the sake of designer.

• ETRI Journal
• /
• v.36 no.1
• /
• pp.167-170
• /
• 2014

In this letter, we propose an unsupervised framework for speech noise reduction based on the recent development of low-rank and sparse matrix decomposition. The proposed framework directly separates the speech signal from noisy speech by decomposing the noisy speech spectrogram into three submatrices: the noise structure matrix, the clean speech structure matrix, and the residual noise matrix. Evaluations on the Noisex-92 dataset show that the proposed method achieves a signal-to-distortion ratio approximately 2.48 dB and 3.23 dB higher than that of the robust principal component analysis method and the non-negative matrix factorization method, respectively, when the input SNR is -5 dB.

• Special Issue of the Society of Naval Architects of Korea
• /
• 2009.09a
• /
• pp.115-122
• /
• 2009

In shipbuilding process, automated marking systems are used to print steel part information on the steel plate. Especially, an automated marking system with a moving ink-head prints characters on each block, which divide the steel plate into a fixed size. Therefore it is necessary to split characters, because some characters can be extended into several blocks. Particularly the algorithm, which splits characters, must guarantee its printing quality in any direction since characters can be printed by any angle.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.21 no.9
• /
• pp.76-80
• /
• 2007

For a more efficient and economical management of substations of power system areas, the concept of substation automation has been introduced using intelligent and ubiquitous IT techniques. In this paper, ubiquitous IT prototype hardware, functions and communication interfaces on an embedded platform for substation automation are proposed. Also, operating system architecture is suggested for the effective implementation of substation automation.

• Journal of Power Electronics
• /
• v.18 no.4
• /
• pp.1190-1200
• /
• 2018

A current sourced bi-directional wireless power transfer (WPT) system is proposed to solve the problems that exist in the bi-directional WPT for vehicle-to-grid (V2G) systems. These problems include the fact that these systems are not safe enough, the output power is limited and the control methods are complicated. Firstly, the proposed system adopts two different compensation and control methods on both the primary and secondary sides. Secondly, based on an AC impedance analysis, the working principle is analyzed and the parameter configuration method with frequency stability is given. In order to output a constant voltage, a bi-directional DC/DC circuit and a controllable rectifier bridge are adopted, which are based on the "constant primary current, constant secondary voltage" control strategy. Finally, the effectiveness and feasibility of the proposed methods are verified by experimental results.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.24 no.6 s.177
• /
• pp.1379-1389
• /
• 2000

In this study, a design process of robotic cell is presented. This paper focuses only on the automation of workpiece handling with robot. The presented design process enables us to analyze effectiv ely the original production system and to redesign it as an optimum production system with robots. An original production system is analyzed with respect to its economical and technological requirements for automation. If automation of the given production system is feasible, the conceptual design for automation is firstly derived. Next, the detail design is derived for the optimum conceptual design. Finally, an optimum system solution is determined after the economical and technical evaluation of all the derived detail designs. The all specifications of each element of the redesigned production system and its layout are determined at the detail design phase. This paper shows a low cost supporting tool for layout design of robotic cell with SCARA type robots.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.7
• /
• pp.85-93
• /
• 1999

In this study, PC-based slicing machine and driving software were constructed for the purpose of automation of semi-conductor cutting process. The biggest feature of software is variation of parameter and include data base, signal monitoring, error report, corresponding action or automatic motion planing. Parameters were drawn and algorithms were developed to make software by GUI interface. The cutting experiment was done for sampled wafer to see the effectiveness of the soft automation. From the experimented and implemented results, it is shown that parameters for automation of slicing process could be drawn, then its algorithms constructed. It could be considered what is the merit of this slicing machine by comparing the PC-based and the NC-based.

• Proceedings of the Korean Institute of Communication Sciences Conference
• /
• 2006.07a
• /
• pp.632-632
• /
• 2006