정보상태, 정보구조, 그리고 담화분석

김해연 中央大學校 人文科學硏究所 2002 人文學硏究 Vol.34 No.-

대화, 사회 행위, 그리고 문법

김해연 中央大學校 人文科學硏究所 2002 人文學硏究 Vol.33 No.-

무선 ATM망에서의 동적 대역폭 할당 알고리즘에 대한 QoS 성능 연구

류기훈,김지연,전광탁,양해권 군산대학교 정보통신기술연구소 2000 情報通信技術硏究論文集 Vol.4 No.-

In the network with small cell radius, a mobile terminal which has large mobility should perform frequent handover. This requires that handover mechanism must be done fastly. As cell size is smaller, signal power level is lower Handover is implemented by the network to give the users freedom of motion beyond a limited wireless coverage area while they are communication. The handover is procedure by which a user's radio link is transferred from one radio port to another through the network without an interruption of the user collection. The currently existing method for handover uses an algorithm, in which the bandwidth corresponding to the adjacent cells is supposed to be allocated. However, this method leads to the problem of requiring bandwidth allocation for many-unknown cells, due to the lack of information toward moving direction in mobile terminal. In this paper, we propose an efficient dynamic bandwidth allocation algorithm for solving those problem above, based on both path rerouting handover and soft hangover mechanism with wireless ATM. Thus, only the bandwidth for corresponding adjacent cell, that is from estimation, is chosen to be reserved; this method drastically reduces the waste of bandwidth, and improves the efficiency in performance. Comparing with static bandwidth allocation algorithm, the proposed algorithm make a bandwidth allocation more efficient. As for the QoS, it has been shown that proposed algorithm shows better performance than that with static bandwidth allocation algorithm.

Imaging Device Identification using Sensor Pattern Noise Based on Wiener Filtering

Hae-Yeoun Lee(이해연) 대한전기학회 2016 전기학회논문지 Vol.65 No.12

Multimedia such as image, audio, and video is easy to create and distribute with the advance of IT. Since novice uses them for illegal purposes, multimedia forensics are required to protect contents and block illegal usage. This paper presents a multimedia forensic algorithm for video to identify the device used for acquiring unknown video files. First, the way to calculate a sensor pattern noise using Wiener filter (W-SPN) is presented, which comes from the imperfection of photon detectors against light. Then, the way to identify the device is explained after estimating W-SPNs from the reference device and the unknown video. For the experiment, 30 devices including DSLR, compact camera, smartphone, and camcorder are tested and analyzed quantitatively. Based on the results, the presented algorithm can achieve the 96.0% identification accuracy.

Satellite Image Processing Software for Value-Added Products

Hae Yeoun Lee,Won Kyu Park,Seung Bum Kim,Tae Jung Kim,Dong Seok Shin,Heung Kyu Lee 大韓遠隔探査學會 1999 大韓遠隔探査學會誌 Vol.15 No.4

To extract value-added products which are important in scientific area and practical life, e.g. digital elevation models, ortho-rectified images and geometric corrected images, Satellite Technology Research Center at Korea Advanced Institute of Science and Technology has developed a satellite image processing software called "Valadd-Pro". In this paper, "Valadd-Pro" software is briefly introduced and its main components such as precise geometric correction, ortho-rectification and digital elevation model extraction component are described. The performance of "Valadd-Pro" software was assessed on 10m resolution 6000×6000 SPOT panchromatic images (60km×60km) using ground control points from GPS measurements. The height accuracy was measured by comparing our results with 100m resolution DTEDs produced by USGS and 60m resolution DEMs generated from digitized contours produced by National Geography Institute. Also, to show the superior performance of "Valadd-Pro" software, we compared the performance with that of commonly used PCI(R) commercial software. Based on the results, the geometric correction of "Valadd-Pro" software needs fewer ground control points than that of PCI(R) software and the ortho-rectification of "Valadd-Pro" software shows similar performance to that of PCI(R) software. In the digital elevation model extraction, "Valadd-Pro" software is two times more accurate and four times faster than PCI(R) software.

선형 Pushbroom 영상의 에피폴라 기하모델 수립을 위한 간소화된 방법론

이해연 ( Hae Yeoun Lee ),박원규 ( Won Kyu Park ) 大韓遠隔探査學會 2002 大韓遠隔探査學會誌 Vol.18 No.2

본 논문에서는 선형 Pushbroom 영상의 에피폴라 기하모델을 수립하기 위한 간소화된 방법을 제안한다. 제안한 알고리즘은 Gupta와 Hartly의 센서모델과 Orun과 Natarajan 센서모델을 사용하여 검증하였고, 각 센서모델에서의 정밀한 에피폴라 기하모델과 정량적인 비교 분석을 수행하였다. 실험을 위해 SPOT 영상과 KOMPSAT 영상을 사용하였고, 각 영상에 대해 20개의 지상기준점을 독립적 검사점으로 사용하였다. 실험 결과에 따르면 제안한 알고리즘은 각 센서모델에서의 정밀한 에피폴라 기하모델과 크게 차이가 없었고 (0.1픽셀 이내), 극단적인 가정 속에서도 충분한 견고함을 보였다. 본 논문에서 제안한 알고리즘은 공선조건식에 기반을 둔 대부분의 센서모델에 대해 적용이 가능하며 신뢰할 수 있는 정확도를 나타낼 것으로 생각한다. In this paper, we proposed a simplified strategy for the epipolarity of linear pushbroom imagery. The proposed strategy is verified on "Gupta and Hartly" sensor model and "Orun and Natarajan" sensor model. It is also compared with the precise epipolarity model of each sensor model on SPOT and KOMPSAT imagery. For the quantitative analysis, 20 ground control points are used as independent checking points. Based on the results, the accuracy of the proposed strategy is not different from that of the precise epipolarity model of each sensor model (below 0.1 pixels). Under the worst circumstance, the proposed strategy is robust. We can assure that the proposed strategy will show high accuracy on most of sensor models based on the co-linearity equations.

뇌 MRI 영상에서 QQ 모델의 클러스터 기반 분류와 정합을 이용한 OEF 계산 방법

이해연(Hae-Yeoun Lee) 한국정보기술학회 2020 한국정보기술학회논문지 Vol.18 No.10

Brain-related diseases have a high cause of death, and magnetic resonance imaging(MRI) is used in clinical practice to prevent and diagnose them. To analyze the function of brain tissue, brain MRI is used to calculate the oxygen extraction rate(OEF), the amount of oxygen consumed in the blood. This paper proposes a method to calculate noise-resistant OEF through cluster-based classification and matching using QQ model in brain MRI. The proposed method uses the real-case inputs to the QQ model to compute the output values and create a database through cluster-based classification. For the unknown output values, it then estimates the input values and calculates the OEF through matching and interpolation with the database The proposed method analyzes 20 patients and healthy subjects, showing that OEF can be estimated with high accuracy and stability. In addition, the average RMSE values of the original OEF and estimated OEF for the proposed method and CAT method in 7 patients and healthy subjects were 6.20 and 7.66, respectively, supporting the superior performance of the proposed method.

Automatic Left Ventricle Segmentation Using Iterative Thresholding and an Active Contour Model With Adaptation on Short-Axis Cardiac MRI

Lee, Hae-Yeoun,Codella, Noel C. F.,Cham, Matthew D.,Weinsaft, Jonathan W.,Wang, Yi IEEE 2010 IEEE Transactions on Biomedical Engineering Vol.57 No.4

<P>An automatic left ventricle (LV) segmentation algorithm is presented for quantification of cardiac output and myocardial mass in clinical practice. The LV endocardium is first segmented using region growth with iterative thresholding by detecting the effusion into the surrounding myocardium and tissues. Then the epicardium is extracted using the active contour model guided by the endocardial border and the myocardial signal information estimated by iterative thresholding. This iterative thresholding and active contour model with adaptation (ITHACA) algorithm was compared to manual tracing used in clinical practice and the commercial MASS Analysis software (General Electric) in 38 patients, with Institutional Review Board (IRB) approval. The ITHACA algorithm provided substantial improvement over the MASS software in defining myocardial borders. The ITHACA algorithm agreed well with manual tracing with a mean difference of blood volume and myocardial mass being 2.9 ± 6.2 mL (mean ± standard deviation) and -0.9 ± 16.5 g, respectively. The difference was smaller than the difference between manual tracing and the MASS software (approximately -20.0 ± 6.9 mL and -1.0 ± 20.2 g, respectively). These experimental results support that the proposed ITHACA segmentation is accurate and useful for clinical practice.</P>

AUTOMATIC ROAD EXTRACTION FROM 1M-RESOLUTION SATELLITE IMAGES

Lee, Hae Yeoun,Park, Won Kyu,Lee, Heung Kyu 대한원격탐사학회 2000 International Symposium on Remote Sensing Vol.16 No.1

This paper addresses the extraction of roads from 1m-resolution satellite images. Among v~u-ious applications of satellite images, it is important to extract roads for Geographic Information System and urban planning, ete. Many approaches have been studied for airborne and low-resolution satellite images. However, these methods cannot be directly applied to high-resolution satellite images mainly because images contain more noises and roads are not line but regions. In this paper, we propose a region-based strategy for the extraction of roads from 1m-resolution satellite images. Firstly, by using an intensity-based segmentation scheme, regions representing road primitives are efficiently segmented. Secondly, road candidates are selected by region adjacency graph based an a prior knowledge about roads. Then, by comparing the profiles of road candidates with its adjacent profiles, roads can be expanded from road candidates. Using this strategy, we can currently extract most of roads identifiable by human in 1 m-resolution IKONOS satellite images.

멀티미디어 처리 : 비지역적 특징값과 서포트 벡터 머신 분류기를 이용한 위변조 지폐 판별 알고리즘

이해연 ( Hae Yeoun Lee ),지상근 ( Sang Keun Ji ) 한국정보처리학회 2013 정보처리학회논문지. 소프트웨어 및 데이터 공학 Vol.2 No.1