• Structural Engineering and Mechanics
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• v.27 no.5
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• pp.625-638
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• 2007

The damage detection process may appear difficult to be implemented for truss structures because not all degrees of freedom in the numerical model can be experimentally measured. In this context, the damage locating vector (DLV) method, introduced by Bernal (2002), is a useful approach because it is effective when operating with an arbitrary number of sensors, a truncated modal basis and multiple damage scenarios, while keeping the calculation in a low level. In addition, the present paper also evaluates the noise influence on the accuracy of the DLV method. In order to verify the DLV behavior under different damages intensities and, mainly, in presence of measurement noise, a parametric study had been carried out. Different excitations as well as damage scenarios are numerically tested in a continuous Warren truss structure subjected to five noise levels with a set of limited measurement sensors. Besides this, it is proposed another way to determine the damage locating vectors in the DLV procedure. The idea is to contribute with an alternative option to solve the problem with a more widespread algebraic method. The original formulation via singular value decomposition (SVD) is replaced by a common solution of an eigenvector-eigenvalue problem. The final results show that the DLV method, enhanced with the alternative solution proposed in this paper, was able to correctly locate the damaged bars, using an output-only system identification procedure, even considering small intensities of damage and moderate noise levels.

• Journal of Sensor Science and Technology
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• v.12 no.3
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• pp.128-138
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• 2003

In this paper, we proposed the algorithm for locating destination address block (DAB) from automatic system to classify packages. For locating DAB, because the size of obtained images is are very large, we select the region of interesting (ROI) to reduce time carrying into algorithm. After selecting the ROI, proposed algorithm is carried out within the ROI. We extract the outline of the handwriting part of the DAB and the rest components within the obtained ROI using thresholding. We carry out labeling to extract each connected component for extracted outline and the rest components. We extract the outline of the handwriting part of the DAB using the geometrical characteristic of the outline of the handwriting part of the DAB among many connected components. The last, we extract the locating DAB using the outline of the handwriting part of the DAB.

• Journal of the Optical Society of Korea
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• v.14 no.4
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• pp.376-382
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• 2010

We propose a novel method to precisely detect car license plates by locating main characters, which are printed with large font size. The regions of the main characters are directly detected without detecting the plate region boundaries, so that license regions can be detected more precisely than by other existing methods. To generate a binary image, multiple thresholds are applied, and segmented regions are selected from multiple binarized images by a criterion of size and compactness. We do not employ any character matching methods, so that many candidates for main character groups are detected; thus, we use a neural network to reject non-main character groups from the candidates. The relation of the character regions and the intensity statistics are used as the input to the neural network for classification. The detection performance has been investigated on real images captured under various illumination conditions for 1000 vehicles. 980 plates were correctly detected, and almost all non-detected plates were so stained that their characters could not be isolated for character recognition. In addition, the processing time is fast enough for a commercial automatic license plate recognition system. Therefore, the proposed method can be used for recognition systems with high performance and fast processing.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2003.11a
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• pp.294-298
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• 2003

In this paper, the modeling and design of high-Q multilayer passives have been investigated, and multilayer diplexer for GSM/DCS applications has been designed and fabricated using the passives. To minimize the system, the configuration of a multilayer inductor has involved a square spiral structure. Modeling of a multilayer inductor was performed by the subsystems of distributed components, and using the modeling the optimal structures of the high-Q multilayer inductor could be designed by analyzing parasitics and couplings which affect their frequency characteristics. Multilayer diplexer for GSM/DCS application has been designed and fabricated using LTCC technology. LPF for GSM band had the passband insertion loss of less than 0.55 dB, the return loss of more than 12 dB, and the isolation level of more than 26 dB by locating attenuation pole at 1800 MHz. HPF for DCS band had the passband insertion loss of less than 0.82 dB, the return loss of more than 11 dB, and the isolation level of more than 38 dB by locating attenuation pole at 930 MHz.

• Journal of the Korean Solar Energy Society
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• v.34 no.5
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• pp.11-22
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• 2014

It is usual to determine silver-town location by people's experienced knowledge or intuition considering many different type of thematic variables simultaneously. This paper is primarily intended to locate sunny silver-town according to catchment-wide solar radiation as single key variable. GIS based solar simulation realistically identified catchment-wide solar radiation in the study area using large scale spatial precision. More than 90% over the worst catchment were identified shadow surfaces while the optimal catchment was heavily covered by sunny radiation surfaces. It is confirmed that standard GIS technology can offers the viable method of measuring and comparing the catchment-wide solar radiation. Guidelines for a replicable methodology are presented to provide a strong theoretical basis for the standardization of factors involved in locating the sunny silver-town; delineation of catchment boundary, solar simulation, catchment-wide comparison etc. They could be used as an evidence to determine sunny catchment in comparison with other catchment, based solar simulation. It is anticipated that this research output could be used as a valuable reference to confirm the potential of introducing the new concept of "catchment specific solar radiation" to support more scientific and objective decision-making in the process of locating silver town.

• Smart Structures and Systems
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• v.14 no.2
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• pp.105-128
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• 2014

The stochastic damage locating vector (SDLV) method has been studied extensively in recent years because of its potential to determine the location of damage in structures without the need for measuring the input excitation. The SDLV method has been shown to be a particularly useful tool for damage localization in steel truss bridges through numerical simulation and experimental validation. However, several issues still need clarification. For example, two methods have been suggested for determining the observation matrix C identified for the structural system; yet little guidance has been provided regarding the conditions under which the respective formulations should be used. Additionally, the specific layout of the sensors to achieve effective performance with the SDLV method and the associated relationship to the specific type of truss structure have yet to be explored. Moreover, how the location of truss members influences the damage localization results should be studied. In this paper, these three issues are first investigated through numerical simulation and subsequently the main results are validated experimentally. The results of this paper provide guidance on the effective use of the SDLV method.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.8
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• pp.3981-4004
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• 2019

This paper proposes a novel method for locating objects in real space from a single remote image and measuring actual distances between them by automatic detection and perspective transformation. The dimensions of the real space are known in advance. First, the corner points of the interested region are detected from an image using deep learning. Then, based on the corner points, the region of interest (ROI) is extracted and made proportional to real space by applying warp-perspective transformation. Finally, the objects are detected and mapped to the real-world location. Removing distortion from the image using camera calibration improves the accuracy in most of the cases. The deep learning framework Darknet is used for detection, and necessary modifications are made to integrate perspective transformation, camera calibration, un-distortion, etc. Experiments are performed with two types of cameras, one with barrel and the other with pincushion distortions. The results show that the difference between calculated distances and measured on real space with measurement tapes are very small; approximately 1 cm on an average. Furthermore, automatic corner detection allows the system to be used with any type of camera that has a fixed pose or in motion; using more points significantly enhances the accuracy of real-world mapping even without camera calibration. Perspective transformation also increases the object detection efficiency by making unified sizes of all objects.

• Journal of the Korean Operations Research and Management Science Society
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• v.8 no.1
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• pp.19-26
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• 1983

This paper deals with the problem of locating facilities with upper and lower capacity bounds in a single level physical distribution system at minimum total costs. Several known schemes for location problems with upper capacity bounds only are successfully extended to our case and then implemented into our branch ana bound solution procedure. Computational experiments with twelve test problems suggest the effectiveness of our approach by showing that only a small amount of additional computation is required for our problem as compared to that for the problems with upper capacity bounds.

• Information and Communications Magazine
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• v.32 no.2
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• pp.89-97
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• 2015

최근 실내에서 사용할 수 있는 무선랜 신호의 증가와 스마트폰 사용자의 폭발적 증가로 무선랜 신호를 이용한 스마트폰의 실내 위치인식에 대한 요구가 커지고 있다. 본 고에서는 전 세계 실내 공간을 대상으로 위치정보를 제공하는 글로벌 실내 위치인식 및 실내,외 통합 내비게이션 서비스 실현에 요구되는 제반 환경과 요소 기술을 위치기술 스택이라는 틀을 통해서 소개한다. 아울러 사용자 참여 방식으로 글로벌 실내 위치인식 시스템을 구현하기 위한 KAIST Indoor Locating System(KAILOS)의 주요 구성 요소와 핵심 요소 기술, 그리고 KAILOS상에서 구현된 KAIST 캠퍼스 실내,외 통합 내비게이션 시스템에 대해서도 소개한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.11a
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• pp.397-400
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• 2004

이전 논문은 자바 프로그램 내에 포함된 논리적인 오류를 발견하기 위해 HDTS 기술을 제안하였다. HDTS 는 알고리즈믹 프로그램 디버깅 기술, 단계적 프로그램 디버깅 기술, 그리고 프로그램 분할을 혼합하여 효율적으로 논리적인 오류가 포함된 프로그램을 디버깅하는 기술이다. 본 논문에서는 HDTS 기술을 구현하기 위한 HDTS 시스템을 설계한다.