• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 C
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• pp.1050-1052
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• 1998

As the power systems evolve, they are incorporating increasingly complex control and protection functions. Due to this, utilities are relying more and more on real-time simulators to study complex system interaction problems. This paper addresses some key questions regarding the needs of such simulators and their characteristic features/requirements. In countries like France and Canada, large scale simulators are developed and placed in practical use, and in others are now under development. Following this background, three typical simulators(ARENE, RTDS/HYPERSIM) will be examined focusing on the purpose, technology and experiences in a real-time simulator. Discussion will be extended to the future issues and potentials of the power system simulation.

• 대한안전경영과학회지
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• 제17권2호
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• pp.97-106
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• 2015

System is the organization of hardware, software, personnel and facilities needed to perform a designated function within a stated environment with specified results. The trend of modern systems is getting more complex and larger. The system is necessary for modern society but the minor malfunction of the system can result the enormous human and material losses. Recently it is being heightened the concern for system safety and required to be built and applied Safety Engineering standard Guideline for safety of complex and large-sized system. This paper describes the System Engineering Process model integrated with Safety Engineering and the establishment of standard safety guidelines for safety of product development using DMADOV Methodology of the Lean 6 Sigma.

• 한국정보전자통신기술학회논문지
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• 제11권5호
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• pp.475-480
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• 2018

In OFDM-based systems, FFT is a critical component since it occupies large area and consumes more power. In this paper, we present a low hardware-cost and low power 512-point pipelined FFT design method for OFDM applications. To reduce the number of twiddle factors and to choose simple design architecture, the radix-$2^4-2^3$ algorithm are exploited. For twiddle factor multiplication, we propose a new canonical signed digit (CSD) complex multiplier design method to minimize the hardware-cost. In hardware implementation with Intel FPGA, the proposed FFT design achieves more than about 28% reduction in gate count and 18% reduction in power consumption compared to the previous approaches.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2006년도 학술발표회 논문집
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• pp.453-460
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• 2006

Stay cables, such as used in cable-stayed bridges, are prone to vibration due to their low inherent damping characteristics. Recently some studies have shown that active and semiactive control system using MR damper can potentially achieve both higher performance levels than passive control system and adaptability with few of the detractions. However, a control system including a power supply, controller, and sensors is required to maximize the performance of the MR damper and this complicated control system is not effective to most of large civil structures. This paper proposes a smart complex damping system which consists of toggle system and MR dampers by introducing electromagnetic induction(EMI) system as an external power source to MR damper. The performance of the proposed damping device has been compared with that of the passive-type control systems employing a MR damper, a linear viscous damper, and EMI system.

• Current Optics and Photonics
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• 제6권5호
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• pp.463-472
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• 2022

At certain wavelengths, single-pixel imaging is considered to be a solution that can achieve high quality imaging and also reduce costs. However, achieving imaging of complex scenes is an overhead-intensive process for single-pixel imaging systems, so low efficiency and high consumption are the biggest obstacles to their practical application. Improving efficiency to reduce overhead is the solution to this problem. Salient object detection is usually used as a pre-processing step in computer vision tasks, mimicking human functions in complex natural scenes, to reduce overhead and improve efficiency by focusing on regions with a large amount of information. Therefore, in this paper, we explore the implementation of salient object detection based on single-pixel imaging after a single pixel, and propose a scheme to reconstruct images based on Fourier bases and use U²Net models for salient object detection.

• 한국균학회지
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• 제51권4호
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• pp.405-410
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• 2023

Erysiphe chloranthi is the only powdery mildew species (Erysiphaceae) found on Chloranthus plants belonging to the family Chloranthaceae. This species has long been known to be present in Japan and Korea and is hence regarded as endemic to East Asia. Examination of seven Korean specimens revealed detailed morphological characteristics of the holomorph of this species. Short foot-cells of conidiophores are proposed as key characteristics that differ from related species. Sequences of the internal transcribed spacer regions and large subunit gene retrieved from four Korean samples confirm the phylogenetic position of this species within the Erysiphe aquilegiae complex. These data may help elucidate the identity of this species and clarify the ambiguity of the E. aquilegiae complex.

• 한국가스학회지
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• 제17권1호
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• pp.49-55
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• 2013

최근 발전, 가스 설비, 화학공장 등의 대형 시스템들은 매우 복잡한 구조를 지니고 있다. 대부분의 공정들은 효율성을 위하여 높은 신뢰성을 요구하고 있으나, 복잡한 과정으로 인하여 신뢰도 분석이 상대적으로 어려운 실정이다. 복잡한 화학공정에서의 신뢰성 분석을 위하여 이 논문에서는 k-out-of-n로 구성된 화학공정을 RBD를 이용하여 신뢰성 경로를 파악하고, 고장판정행렬을 적용하여 신뢰도를 계산하였다. 이 기법이 k-out-of-n 시스템의 신뢰성 분석에 유용하게 사용될 수 있다는 것을 제시하였다.

• 한국정보기술응용학회:학술대회논문집
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• 한국정보기술응용학회 2002년도 추계공동학술대회 정보환경 변화에 따른 신정보기술 패러다임
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• pp.417-422
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• 2002

네트워크와 인터넷의 급격한 성장과 함께 기존의 많은 소프트웨어들이 웹 기반으로 그 모습을 변화하고 있으며, 이로 인해 웹 어플리케이션의 복잡성이 증가되고 개발에 있어 많은 비용과 인력이 소요되고 있다. 하지만 아직까지 웹 어플리케이션을 위한 명확한 개발 환경이 정의되지 않았으며 대부분이 경험에 입각하여 나름대로 개발하고 있는 실정이다. 따라서 웹의 특성을 잘 반영하는 개발 환경의 구축이 무엇보다 중요시된다. 본 논문에서는 웹 환경의 특성을 파악하여 웹 어플리케이션 개발에 적합한 프로세스를 정의하고 이에 따라 모델링 할 수 있는 환경을 제시한다 또한 모델링 결과를 바탕으로 자동으로 소스코드를 생성한다. 결국 분석과 설계 단계에서 발생되는 결함을 줄여 품질을 향상하고, 개발하는데 드는 시간을 줄여 생산성을 향상함으로써 빠르게 변화하는 웹 환경에 능동적으로 대처하고자 한다.

• 제어로봇시스템학회논문지
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• 제12권8호
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• pp.746-751
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• 2006

In this paper, we present tracking algorithm for the indoor moving object. We research passive method using a camera and image processing. It had been researched to use dynamic based estimators, such as Kalman Filter, Extended Kalman Filter and Particle Filter for tracking moving object. These algorithm have a good performance on real-time tracking, but they have a limit. If the shape of object is changed or object is located on complex background, they will fail to track them. This problem will need the complicated image processing algorithm. Finally, a large algorithm is made from integration of dynamic based estimator and image processing algorithm. For eliminating this inefficiency problem, image based estimator, Mean-shift Algorithm is suggested. This algorithm is implemented by color histogram. In other words, it decide coordinate of object's center from using probability density of histogram in image. Although shape is changed, this is not disturbed by complex background and can track object. This paper shows the results in real camera system, and decides 3D coordinate using the data from mean-shift algorithm and relationship of real frame and camera frame.

• International Journal of Naval Architecture and Ocean Engineering
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• 제4권3호
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• pp.291-301
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• 2012

A scalar metric for the assessment of hull surface producibility was known to be useful in estimating the complexity of a hull form of ships or large offshore structures by looking at their shape. However, it could not serve as a comprehensive measuring tool due to its lack of important components of the hull form such as longitudinals, stiffeners, and web frames attached to the hull surface. To have a complete metric for cost estimation, these structural members must be included. In this paper, major inner structural members are considered by measuring the complexity of their geometric shape. The final scalar metric thus consists of the classes containing inner members with various curvature magnitudes as well as the classes containing curved plates with single and double curvature distribution. Those two distinct metrics are merged into a complete scalar metric that accounts for the total cost estimation of complex structural bodies.