• Structural Engineering and Mechanics
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• 제33권4호
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• pp.485-502
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• 2009

A new 8-node serendipity quadrilateral plate bending element (MQP8) based on the Mindlin-Reissner theory for the analysis of thin and moderately thick plate bending problems using Integrated Force Method is presented in this paper. The performance of this new element (MQP8) is studied for accuracy and convergence by analyzing many standard benchmark plate bending problems. This new element MQP8 performs excellent in both thin and moderately thick plate bending situations. And also this element is free from spurious/zero energy modes and free from shear locking problem.

• Journal of Electrical Engineering and Technology
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• 제9권4호
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• pp.1202-1209
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• 2014

A novel integrated optimization method is proposed to combine both generation and transmission line expansion problem considering bus voltage limit. Most of the existing researches on the combined generation and transmission expansion planning cannot consider bus voltages and reactive power flow limits because they are mostly based on the DC power flow model. In this paper the AC power flow model and nonlinear constraints related to reactive power are simplified and modified to improve the computation time and convergence. The proposed method has been successfully applied to Garver's six-bus system which is one of the most frequently used small scale sample systems to verify the transmission expansion method.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.266.1-266.1
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• 2013

Large-scale single-crystal organic nanowire arrays were generated using a direct printing method (liquidbridge- mediated nanotransfer molding) that enables the simultaneous synthesis, alignment and patterning of nanowires from molecular ink solutions. Using this method, single-crystal organic nanowires can easily be synthesized by self-assembly and crystallization of organic molecules within the nanoscale channels of molds, and these nanowires can then be directly transferred to specific positions on substrates to generate nanowire arrays by a direct printing process. Repeated application of the direct printing process can be used to produce organic nanowire-integrated electronics with two- or three-dimensional complex structures on large-area flexible substrates. This efficient manufacturing method is used to fabricate all-organic nanowire field-effect transistors that are integrated into device arrays and inverters on flexible plastic substrates.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.1360-1365
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• 2008

Most recognition algorithms for intelligent surveillance system are based on analysis of the video collected from one camera. Video analysis is also used to compute the internal parameters used in the recognition process. The algorithm computes only the video of the fixed area so that it is a insufficient method and it could not use information of the related areas. However, intelligent integrated surveillance system should be constructed to correlate the events in the other areas as well as in the fixed area. In this paper, in order to construct the intelligent integrated surveillance system, we describe the method not to focus on the video of each camera but to aware the whole event by sharing information between cameras, which is more accurate. The method would be used to aware the event in the fixed area such as stations in urban transit.

• Environmental Engineering Research
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• 제11권2호
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• pp.63-76
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• 2006

Multivariate analysis and batch monitoring on a pilot-scale sequencing batch reactor (SBR) are described for integrated wastewater treatment management system, where a batchwise multiway independent component analysis method (MICA) are used to extract meaningful hidden information from non-Gaussian wastewater treatment data. Three-way batch data of SBR are unfolded batch-wisely, and then a non-Gaussian multivariate monitoring method is used to capture the non-Gaussian characteristics of normal batches in biological wastewater treatment plant. It is successfully applied to an 80L SBR for biological wastewater treatment, which is characterized by a variety of error sources with non-Gaussian characteristics. The batchwise multivariate monitoring results of a pilot-scale SBR for integrated wastewater treatment management system showed more powerful monitoring performance on a WWTP application than the conventional method since it can extract non-Gaussian source signals which are independent and cross-correlation of variables.

• Journal of Electrical Engineering and Technology
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• 제9권5호
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• pp.1614-1622
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• 2014

A novel equivalent flux sliding-mode observer (SMO) is proposed for dual three-phase interior permanent magnet synchronous motor (DT-IPMSM) drive system in this paper. The DT-IPMSM has two sets of Y-connected stator three-phase windings spatially shifted by 30 electrical degrees. In this method, the sensorless drive system employs a flux SMO with soft phase-locked loop method for rotor speed and position estimation, not only are low-pass filter and phase compensation module eliminated, but also estimation accuracy is improved. Meanwhile, to get the regulator parameters of current control, the inner current loop is realized using a decoupling and diagonal internal model control algorithm. Experiment results of 2MW-level DT-IPMSM drives system show that the proposed method has good dynamic and static performances.

• 한국ITS학회 논문지
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• 제14권4호
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• pp.1-9
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• 2015

도로상에 다양한 ITS 장비들의 제어기 함체를 하나의 함체로 물리적 기능적으로 통합하고자 개발중인 통합표준제어기의 설치위치에 대한 논리적인 근거나 도출방법이 마련되어 있지 못하여 현장적용에 어려움이 발생하고 있다. 특히, 노드부와 링크부 등 거리상 여러 곳에 분산 설치된 개별 제어기들을 통합하기 위한 최적의 위치를 도출하는 표준화된 방법론의 정립이 필요하다. 따라서 본 연구는 새로이 개발되는 통합표준제어기의 보다 합리적이며 효율적인 위치결정방법론을 제시하는 것을 목적으로 한다. 이를 위해 여기에서는 도시계획에서 시설입지결정에 활용하는 센트로이드를 활용하여 해결방안을 모색하였다. 분석결과 센트로이드 중에서 모든 장비에 균등한 연계가 가능한 중앙점(central point)의 적용이 가장 합리적인 것으로 나타났으며, 좌표계 설정을 통해 도로상에 정확한 좌표와 존을 설치위치로 제시하고 있다. 본 연구에서 제시한 방법론은 통합표준제어기의 시장 확대에 따른 현장적용에 활용도가 높을 것으로 보인다.

• 한국통신학회논문지
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• 제19권9호
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• pp.1748-1758
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• 1994

최근에 이동통신의 수요가 급격히 증가하고 있으며, 음성뿐만 아니라 종합정보통신망(ISDN)에서 제공되는 데이터, 팩스, 영상 등의 비음성계 서비스가 요구되고 있다. 따라서 본 논문에서는 PCS 시스템의 기본 핵심기술로 활용될 수 있는 디지털 셀룰러 CDMA 시스템용 음성/데이터 집적 서비스 방안들을 제시하고 컴퓨터 심뮬레이션을 통하여 각 집적 서비스 방안의 성능을 비교 분석한다. 컴퓨터 시뮬레이션 결과, CDMA의 한 논리채널을 여러 단말기가 할당받아 PRMA 방식으로 경쟁하는 PR-CDMA 음성/데이타 집적 서비스 방안이 CDMA 방식의 단점인 고정 채널갯수의 한계와 채널이용율의 저하를 극복할 수 있어 전용단말기나 음성/데이타 집적단말기를 이용한 광대역 CDMA 음성/데이타 집적서비스 방안 보다 모든 면에서 우수한 성능을 나타냄을 알 수 있었다.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2001년도 The Pacific Aisan Confrence On Intelligent Systems 2001
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• pp.211-218
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• 2001

This paper introduces a method of constructing expert systems in an integrated environment for automatic software design. This integrated environment may be applicable from top-level system architecture design, data flow diagram design down to flow chart and coding. The system is integrated with three CASE tools, FSD (Functional Structure Diagram), DFD (Data Flow Diagram) and structured chart PAD (Problem Analysis Diagram), and respective expert systems with automatic design capability by reusing past design. The construction way of these expert systems is based on systematic acquisition of design knowledge stemmed from a systematic design work process of well-matured developers. The design knowledge is automatically acquired from respective documents and stored in the respective knowledge bases. By reusing it, a similar software system may be designed automatically. In order to develop these expert systems in a short period, these design knowledge is expressed by the unified frame structure, functions of th expert system units are partitioned mono-functions and then standardized components. As a result, the design cost of an expert system can be reduced to standard work procedures. Another feature of this paper is to introduce the integrated environment for automatic software design. This system features an essentially zero start-up cost for automatic design resulting in substantial saving of design man-hours in the resulting in substantial saving of design man-hours in the design life cycle, and the expected increase in software productivity after enough design experiences are accumulated.

• Journal of Magnetics
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• 제22권1호
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• pp.49-54
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• 2017

The significant reduction of the image quality caused by the magnetic field of samples is a major problem affecting the application of SEM (scanning electron microscopy) in the analysis of electronic devices. The main reason for this is that the electron trajectory is deflected by the Lorentz force. The usual solution to this problem is degaussing the sample at high temperatures. However, due to the poor heat resistance of some electronic components, it is imperative to find a method that can reduce the impact of magnetic field on the image quality and is straightforward and easy to operate without destroying the sample. In this paper, the influence of different magnetic field directions on the imaging quality was discussed by combining the experiment and software simulation. The principle of the method was studied, and the best observation direction was obtained.