• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.578-581
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• 2006

Usually to achieve precise geolocation of satellite images, we need to get GCPs (Ground control points) from individual scenes. This requirement greatly increases the cost and processing time for satellite mapping. In this article, we focus on finding appropriate sensor models for entire image strips composing of several adjacent scenes. We tested the feasibility of modelling whole satellite image strips by establishing sensor models of one scene with GCPs and by applying the models to neighboring scenes without GCPs. For this, we developed two types of sensor models: collinearity-based type and orbit-based type and tested them using different sets of unknowns. Results indicated that although the performance of two types was very similar, for modelling individual scenes, it was not for modelling the whole strips. Moreover, the performance of sensor models was remarkably sensitive to different sets of unknowns. It was found that the orbit-based model using attitude biases as unknowns can be used to model SPOT image strips of 420 Km in length.

• 방송공학회논문지
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• 제21권2호
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• pp.272-275
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• 2016

본 논문은 위성 영상을 위한 안개 제거 및 표면반사율 기반의 특징점 검출 방법을 제안한다. 기존의 안개 제거를 위한 DCP 방법은 패치 기반의 처리 방식으로 인해 전달맵 생성 과정에서 블록현상이 발생하게 되고, 이는 영상을 흐리게 하는 원인이 된다. 따라서 제안한 은닉마코프 기반의 방법은 영상의 블록 현상을 제거하고 선명도를 향상한다. 또한 표면반사율 기반의 견고한 특징점 추출을 통해서 영상 정합의 정확성을 향상하였다. 실험을 통해 제안한 방법이 기존 방법에 비해 안개 제거의 성능에서 우수함을 확인하였으며 이를 통해 특징 검출 및 위성 영상 정합에 적합함을 확인하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제6권1호
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• pp.426-445
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• 2012

Conventional rate control (RC) schemes for H.264 video coding usually regulate output bit rate to match channel bandwidth by adjusting quantization parameter (QP) at fixed full frame rate, and the passive frame skipping to avoid buffer overflow usually occurs when scene changes or high motions exist in video sequences especially at low bit rate, which degrades spatial-temporal quality and causes jerky effect. In this paper, an active content adaptive frame skipping scheme is proposed instead of passive methods, which skips subjectively trivial frames by structural similarity (SSIM) measurement between the original frame and the interpolated frame via motion vector (MV) copy scheme. The saved bits from skipped frames are allocated to coded key ones to enhance their spatial quality, and the skipped frames are well recovered based on MV copy scheme from adjacent key ones at the decoder side to maintain constant frame rate. Experimental results show that the proposed active SSIM-based frameskip scheme acquires better and more consistent spatial-temporal quality both in objective (PSNR) and subjective (SSIM) sense with low complexity compared to classic fixed frame rate control method JVT-G012 and prior objective metric based frameskip method.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.559-563
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• 2000

In this paper we describe a method for aligning a robot gripper using image information. The region of gripper is represented from HSI color model that has major advantage of brightness independence. In order to extract the feature points for vision based position control, we find the corners of gripper shape using polygonal approximation method which determines the segment size and curvature of each points. We apply the vision based scheme to the task of alignment of gripper to reach the desired position by 2 RGB cameras. Experiments are carried out to exhibit the effectiveness of vision based control using feature points from polygonal approximation of gripper.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 D
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• pp.2609-2611
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• 2003

In this study, we explain the process and the technique required for implementing web-based remote control system based on embedded processor, SAl110, and embedded Linux. At first. cross-compile environment for target system should be constructed on host computer, and bootloader in charge of Linux booting may be loaded on the target system. Then, kernel image is compiled and loaded on the target system. Embedded Linux porting process is completed when ram disk image is generated. Finally, we load wed-server and device driver on the ram disk and make web-page for remote control using CGI. Through the above process, we implement web-based remote control system and present the result.

• 보건교육건강증진학회지
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• 제18권3호
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• pp.163-175
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• 2001

The purpose of this study is to collect fundamental data for weight control education based on obesity, weight control practices and body image in female college students. Those surveyed were 364 female college students attending universities in Seoul, Kyoung-Gi and Chung Cheung Buk Do. The data were collected from June 1, 1999 to September 10, 1999. The resulting data are as follows: 1. The mean BMI of the female college students was 19.78:t1.87kg/$\textrm{m}^2$, which comes within the range of normal weight. Underweight, normal weight and overweight students were respectively 27.2%, 66.8% and 5.5%. As many as 7.1% of the underweight students and 42.8% of the normal weight students described themselves as being "fatty". 2. Of these subjects, 83.5% reported wanting to lose weight, and the primary reason of weight control was to improve their appearance. The mean weight that they wanted to lose was 5.2$\pm$2.7kg, and 68.7% of the respondents had tried to lose weight. Among them, the most frequently reported weight control behavior was dieting followed by exercise, 30% reported fasting, 3.6% reported using drugs, 4.4% reported smoking and 3.6% reported vomiting. As to the weight loss effect, 96.7% of the subjects used behavior modification, 82.5% of the students exercised, and 76.1% of the dieters reported they had lost weight. 3. As to body image, many female college students were dissatisfied with their body figures, especially thighs(70.3%), hips(60.4%), abdomens(60.2%), and weight(55.2%). The body image of the students that perceived themselves as "fatty" was the lowest. 4. There were significant differences in the mean weight that they wanted to lose and the weight control attempts according to weight perception. Those that perceived themselves as "fatty" wanted to lose more weight, and had more weight control experiences. In conclusion, attempts at weight control are common in the female college students and many students appear to be dissatisfied with their body shapes. It is important to educate about healthy weight control methods and raise their awareness of the positive body image.ss of the positive body image.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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• pp.227-235
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• 2000

Agricultural products are easily deformable its shape because of some external forces. However, these force behavior is difficult to measure quantitatively. Until now, many researches on the mechanical property was performed with various methods such as material testing, chemical analysis and non-destructive methods. In order to investigate force behavior on the cellular unit of agricultural products, electro-microscope based 3D image processing method will contribute to analysis of plant cells behavior. Before image measurement of plant cells, plant sample was cut off cross-sectioned area in a size of almost 300-400 ${\mu}$ m units using the micron thickness device, and some of preprocessing procedure was performed with fixing and dyeing. However, the wall structure of plant cell is closely neighbor each other, it is necessary to separate its boundary pixel. Therefore, image merging and shrinking algorithm was adopted to avoid disconnection. After then, boundary pixel was traced through thinning algorithm. Each image from the electro-microscope has a information of x,y position and its height along the z axis cross sectioned image plane. 3D image was constructed using the continuous image combination. Major feature was acquired from a fault image and measured area, thickness of cell wall, shape and unit cell volume. The shape of plant cell was consist of multiple facet shape. Through this measured information, it is possible to construct for structure shape of unit plant cell. This micro unit image processing techniques will contribute to the filed of agricultural mechanical property and will use to construct unit cell model of each agricultural products and information of boundary will use for finite element analysis on unit cell image.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권8호
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• pp.2881-2894
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• 2014

In complicated environment, context information plays an important role in image segmentation/labeling. The recently proposed auto-context algorithm is one of the effective context-based methods. However, the standard auto-context approach samples the context locations utilizing a fixed radius sequence, which is sensitive to large scale-change of objects. In this paper, we present a scale invariant auto-context (SIAC) algorithm which is an improved version of the auto-context algorithm. In order to achieve scale-invariance, we try to approximate the optimal scale for the image in an iterative way and adopt the corresponding optimal radius sequence for context location sampling, both in training and testing. In each iteration of the proposed SIAC algorithm, we use the current classification map to estimate the image scale, and the corresponding radius sequence is then used for choosing context locations. The algorithm iteratively updates the classification maps, as well as the image scales, until convergence. We demonstrate the SIAC algorithm on several image segmentation/labeling tasks. The results demonstrate improvement over the standard auto-context algorithm when large scale-change of objects exists.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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• pp.285-289
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• 1999

A processing system to produce cloud-free composite image data set was developed. In the process, a fine geometric correction based on orbit parameters and ground control points and radiometric correction based on 6S code are applied. Presently, by using AVHRR image data received at Tokyo, Okinawa, Ulaanbaatar and Bangkok, data set of 10 days composite images covering almost whole Asian region.

• Journal of Information Processing Systems
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• 제12권4호
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• pp.631-643
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• 2016

Due to the block-based discrete cosine transform (BDCT), JPEG compressed images usually exhibit blocking artifacts. When the bit rates are very low, blocking artifacts will seriously affect the image's visual quality. A bilateral filter has the features for edge-preserving when it smooths images, so we propose an adaptive-weighted bilateral filter based on the features. In this paper, an image-deblocking scheme using this kind of adaptive-weighted bilateral filter is proposed to remove and reduce blocking artifacts. Two parameters of the proposed adaptive-weighted bilateral filter are adaptive-weighted so that it can avoid over-blurring unsmooth regions while eliminating blocking artifacts in smooth regions. This is achieved in two aspects: by using local entropy to control the level of filtering of each single pixel point within the image, and by using an improved blind image quality assessment (BIQA) to control the strength of filtering different images whose blocking artifacts are different. It is proved by our experimental results that our proposed image-deblocking scheme provides good performance on eliminating blocking artifacts and can avoid the over-blurring of unsmooth regions.