• 정보처리학회논문지D
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• 제11D권2호
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• pp.305-316
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• 2004

XML은 그 스키마가 비정규적이고 불완전한 특성을 가지고 있는 반구조적(semistructured) 데이터로써 인터넷 상의 데이터를 교환하기 위한 사실상의 표준이 되고 있다. 따라서 이러한 데이터를 효율적으로 다루기 위해서는 어떠한 저장장치에 어떠한 방식으로 저장하느냐가 중요한 요인이 된다. 본 연구에서는 기존의 객체-관계형 데이터베이스의 장점을 활용하면서도 DTD에 상관없이 XML 질의 언어에서 요구하는 다양한 질의 종류를 지원할 수 있는 저장 기법을 개발하였다. 이 기법은 XML 데이터 모델의 비정규적인 특성 때문에 발생할 수 있는 오버헤드를 최소화시키고 현존하는 데이터와 자연스럽게 연계할 수 있다.

• 정보처리학회논문지B
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• 제10B권7호
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• pp.823-828
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• 2003

이 논문의 주요 목적은 내용을 기반으로 하는 이미지 검색에서 이미지 객체의 외형특징을 추출하는 방법을 제시하는 것이다. 대부분의 실질적인 객체들의 외형은 불규칙적이고, 이러한 객체를 수치화하기위한 일반적인 방법은 없다. 특히 전자 카타로그들은 상품들을 나타내는 많은 이미지를 포함하고 있다. 이 논문에서는 이미지 전체가 아닌 이미지내의 개별 객체들을 기반으로 특징을 추출하는 방법을 제시한다. 왜냐하면 제시된 방법은 한 이미지내에서 RLC lines을 사용하여 각 객체들의 외형을 기반으로하는 방법을 사용하기 때문이다. 실험결과는 일반적으로 가장 많이 사용하는 특징인 Texture와 비교를 했고 제시된 외형을 나타내는 변수들이 전자카타로그의 이미지 객체들을 뚜렷하게 나타냈고, 보다 정확하게 객체들을 분류하고 구별하였다.

• 대한의용생체공학회:의공학회지
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• 제29권6호
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• pp.436-442
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• 2008

Magnetic resonance electrical impedance tomography(MREIT) has been suggested to produce cross-sectional conductivity images of an electrically conducting object such as the human body. In most previous studies, recessed electrodes have been used to inject imaging currents into the object. An MRI scanner was used to capture induced magnetic flux density data inside the object and a conductivity image reconstruction algorithm was applied to the data. This paper reports the performance of a thin and flexible carbon-hydrogel electrode that replaces the bulky and rigid recessed electrode in previous studies. The new carbon-hydrogel electrode produces a negligible amount of artifacts in MR and conductivity images and significantly simplifies the experimental procedure. We can fabricate the electrode in different shapes and sizes. Adding a layer of conductive adhesive, we can easily attach the electrode on an irregular surface with an excellent contact. Using a pair of carbon-hydrogel electrodes with a large contact area, we may inject an imaging current with increased amplitude primarily due to a reduced average current density underneath the electrodes. Before we apply the new electrode to a human subject, we evaluated its performance by conducting MREIT imaging experiments of five swine legs. Reconstructed conductivity images of the swine legs show a good contrast among different muscles and bones. We suggest a future study of human experiments using the carbon-hydrogel electrode following the guideline proposed in this paper.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2022년도 추계학술대회
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• pp.562-565
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• 2022

최근 증가하고 있는 도로 위 적재 불량 화물차는 비정상적인 무게 중심으로 인해 물체 낙하, 도로 파손, 연쇄 추돌 등 교통 안전에 위해가 되고 한번 사고가 발생하면 큰 피해가 유발할 수 있다. 하지만 이러한 비정상적인 무게 중심은 적재 불량 차량 인식을 위한 주행 중 축중 시스템으로는 검출이 불가능하다는 한계점이 있다. 본 논문에서는 이러한 사회 문제를 야기하는 적재 불량 차량을 관리하기 위한 객체 인식 기반 AI 모델을 구축하고자 한다. 또한 AI-Hub에 공개된 약 40만장의 대형차, 소형차, 중형차 별 적재 불량 차량과 일반차량으로 구분 된 데이터 셋 중 종류별로 제공되는 CCTV, 블랙박스, 카메라 시점의 적재 불량 차량 데이터 셋을 분석하여 전처리를 통해 적재 불량 차량 검지 AI 모델의 성능을 향상시키는 방법을 제시한다. 이를 통해, 원시 데이터를 활용한 학습 성능 대비 약 23% 향상된 적재 불량 차량의 검출 성능을 나타냄을 보였다. 본 연구 결과를 통해 공개 빅데이터를 보다 효율적으로 활용하여, 객체 인식 기반 적재 불량 차량 탐지 모델 개발에 적용할 수 있을 것으로 기대된다.

• IEIE Transactions on Smart Processing and Computing
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• 제6권3호
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• pp.168-174
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• 2017

Videos recorded on surveillance cameras or by car black boxes at night have distorted images due to illumination variation. Therefore, it is difficult to analyze morphological characteristics of objects, and it is limiting to use such distorted images as evidence in traffic accidents. Image restoration is performed by amplifying the brightness of nighttime images using linearized gamma correction to increase their contrast (which destroys visual information) and by minimizing degradation factors caused by irregular traveling.

• Journal of Biosystems Engineering
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• 제19권4호
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• pp.301-310
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• 1994

The feasibility of using ultrasonic-wave doppler sensors for a measurement of the actual ground speed of agricultural machines was investigated. The actual ground speed is estimated from the doppler shift frequencies of the two ultrasonic-waves transmitted to and received from a moving object. A prototype of the speed-measurement system was designed and constructed for the performance test. The measurement system showed a good performance with a flat surface at speeds lower than 3m/s. However, it was failed to receive the reflected signals from the rough and irregular soil surfaces. Further researches to solve this problem and to improve its performance are now underway.

• 한국공간정보시스템학회:학술대회논문집
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• 한국공간정보시스템학회 2003년도 추계학술대회
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• pp.159-162
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• 2003

In this paper, to find probable collision positions between moving object and terrain in 3D space efficiently, we use a model, similar to Ray Tracing, which finds the triangles intersected by a directed line segment from a large amount of triangles. We try to reduce dead space as much as possible to find candidate triangles intersected by a directed line segment than previous work's. A new modified octree, LBV-Octree(Least Bounding Voxel Octree), is proposed, and we have a ray tracing with it. In the experiment, ray tracing with LBV-Octree provides $5%{\sim}11%$ better performance than with classical octree.

• 한국CDE학회논문집
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• 제20권1호
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• pp.55-64
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• 2015

The earthquake is a natural disaster causing loss of life or property damage and happens more often in Korea recently. Moreover, considering the increase of massive buildings, it is required to predict and visualize the information of the vibration in a building. In this paper, we developed a prototype framework to visualize the displacement information in the AR environments. In order to avoid the irregular halts of the scene and the unnatural distortion of the object, this framework uses the synchronization method at the scene update time and the interpolation of the sensor data for the displacement of vertices. In addition, we studied displacement estimation methods with the acceleration data to extend this framework to the system with accelerators.

• 한국표면공학회지
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• 제26권2호
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• pp.45-54
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• 1993

In this study, magnetic properties of anodized Al film deposited with ferro-magnetic metals in the capacity of perpendicular magnetic recording media were measured and evaluated to find out the role of structure and morphology of the oxide films on magnetic characteristics. The object of this work was to present the conditions of magnetic thin film formation with more superior magnetic property. Anodizing was carried out under various conditions, and then the anodized film were electro-deposited with Co, Ni, Fe and their alloys. Coercive force and residual magnetization in perpendicular direction increased as the pore length of anodized film increased. It was attributed to the increase of the amount of depoisted metals and the ratio of length/diameter of pores. Morphology of anodized films in phosperic acid was not similar to that of sulfuric acid, and thin films in the former solution had perpendcular magnetic anisostropy because of large diameter, irregular length and distribution of the pores. It was found that magnetic properties of the thin films, which had doubled layer of two metals, were dominated by the metal electrodeposited on the surface of the anodized oxide films.

• 한국BIM학회 논문집
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• 제9권2호
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• pp.21-28
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• 2019

Recently, many scan projects are gradually increasing for maintenance, construction. The scan data contains useful data, which can be generated in the target application from the facility, space. However, modeling the scan data required for the application requires a lot of cost. In example, the converting 3D point cloud obtained from scan data into 3D object is a time-consuming task, and the modeling task is still very manual. This research proposes Scan-to-Geometry Mapping Rule Definition (S2G-MD) which maps point cloud data to geometry for irregular building plane objects. The S2G-MD considers user use case variability. The method to define rules for mapping scan to geometry is proposed. This research supports the reverse engineering semi-automatic process for the building planar geometry from the user perspective.