• Title/Summary/Keyword: Space Images

Search Result 2,338, Processing Time 0.032 seconds

Automatic Detection of Absorption Features for Hyperspectral Images

  • Hsu, Pai-Hui;Tseng, Yi-Hsing
    • Proceedings of the KSRS Conference
    • /
    • 2003.11a
    • /
    • pp.700-702
    • /
    • 2003
  • A new method for automatic detection of absorption features is proposed. This method is based on the modulus maximum of the scale-space image calculated by continuous wavelet transform. This method is computationally efficient as compared to traditional methods. The continuum removal algorithm is than implemented on the detected absorption features to reduce some additive factors caused by other absorbing of materials. The results show that the chlorophyll absorption features are detected exactly.

  • PDF

Photometry of MIRIS Paschen-α blobs detected in Cepheus

  • Kim, Il-Joong;Pyo, Jeonghyun;Jeong, Woong-Seob;Park, Won-Kee;Kim, Min Gyu;Lee, Dukhang;Moon, Bongkon;Park, Sung-Joon;Park, Youngsik;Lee, Dae-Hee;Han, Wonyong
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.41 no.2
    • /
    • pp.55.3-55.3
    • /
    • 2016
  • By comparing MIRIS Paschen-${\alpha}$ ($Pa{\alpha}$) Galactic Plane Survey (MIPAPS) data with Anderson's H II region catalog (the most complete Galactic H II region catalog up to date), we confirmed $Pa{\alpha}$ detections from ~50% of the H II region candidates in Cepheus (Galactic longitude from $+96^{\circ}$ to $116^{\circ}$). The detection of the hydrogen recombination line identifies these candidates as clear H II regions. If we extend this result to the whole plane, more than 1000 candidates are expected to be identified as H II regions. In this contribution, we present the results of quantitative estimations (brightness, size, etc.) for the $Pa{\alpha}$ blobs detected in Cepheus. To obtain intensity of $Pa{\alpha}$ emission line, we perform background and point spread function (PSF) matching between two filter images (line and continuum filters) as well as flux calibration.

  • PDF

A Study on the inflow of Sunlight through the Active Building Skin - Focusing on Works of Herzog & de Meuron - (활성표피를 통한 빛의 유입에 관한 연구 - 헤르조그 & 드 뫼롱의 작품을 중심으로 -)

  • Na, Ha-Na;Park, Boo-Mee
    • Korean Institute of Interior Design Journal
    • /
    • v.26 no.4
    • /
    • pp.30-41
    • /
    • 2017
  • Sunlight is perceived by human beings first through the epidermis to space, and is a non - material medium that provides physical awareness of space, diversified expression of spaces, and plenty experience. The purpose of this study is to investigate the characteristics of active building skin based on the inflow of natural light required by humans, looked through among the works of Jacques Herzog & Pierre de Meuron, which show the characteristics of active building skin, TEA(Tenerife Espacio de las Artes, 2008), Messe Basel New Hall (2013) and Elbphilharmonie (2016). First, the interaction between Sunlight and space is divided into spatial characteristics and sensitivities according to their concepts, properties, and characteristics. The characteristics of active skin by light are classified into a physical approach and a constructive approach. Second, (El Croquis 152/153) and analyzed the images, detail drawings, and elevations, and simulated them in 3D to express the relationship between light and active building skin. Third, the changes of light intensity, light color, and distribution of light according to the time of light entering and the skin are determined from 6:00 am to 6:00 pm. Fourth, the images taken from January 30th to February 7th, 2017 on the site were compared with the computer simulated images, and the relationship between active skin and light was compared. This study is to recognize the existence and necessity of light required for human being through the activated epidermis differentiated from the limited or closed epidermis focused on information transmission, I would like to emphasize that I would like to take a step closer to the necessity and possibility of new attempts and developments so that I can feel the various experiential spaces by.

Fast Dimming Associated with a Coronal Jet Seen in Multi-Wavelength and Stereoscopic Observations

  • Lee, K.S.;Innes, D.E.;Moon, Y.J.;Shibata, K.;Lee, Jin-Yi
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.37 no.1
    • /
    • pp.89.1-89.1
    • /
    • 2012
  • We have investigated a coronal jet observed near the limb on 2010 June 27 by the Hinode/X-Ray Telescope (XRT), EUV Imaging Spectrograph (EIS), and Solar Optical Telescope (SOT), and the SDO/Atmospheric Imaging Assembly (AIA), Helioseismic and Magnetic Imager (HMI), and on the disk by STEREO-A/EUVI. From EUV (AIA and EIS) and soft X-ray (XRT) images we have identified both cool and hot jets. There was a small loop eruption in Ca II images of the SOT before the jet eruption. Using high temporal and multi wavelength AIA images, we found that the hot jet preceded its associated cool jet by about 2 minutes. The cool jet showed helical-like structures during the rising period. According to the spectroscopic analysis, the jet's emission changed from blue to red shift with time, implying helical motions in the jet. The STEREO observation, which enabled us to observe the jet projected against the disk, showed that there was a dim loop associated with the jet. We have measured a propagation speed of ~800 km/s for the dimming front. This is comparable to the Alfven speed in the loop computed from a magnetic field extrapolation of the HMI photospheric field measured 5 days earlier and the loop densities obtained from EIS Fe XIV line ratios. We interpret the dimming as indicating the presence of Alfvenic waves initiated by reconnection in the upper chromosphere.

  • PDF

No-reference Image Blur Assessment Based on Multi-scale Spatial Local Features

  • Sun, Chenchen;Cui, Ziguan;Gan, Zongliang;Liu, Feng
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.14 no.10
    • /
    • pp.4060-4079
    • /
    • 2020
  • Blur is an important type of image distortion. How to evaluate the quality of blurred image accurately and efficiently is a research hotspot in the field of image processing in recent years. Inspired by the multi-scale perceptual characteristics of the human visual system (HVS), this paper presents a no-reference image blur/sharpness assessment method based on multi-scale local features in the spatial domain. First, considering various content has different sensitivity to blur distortion, the image is divided into smooth, edge, and texture regions in blocks. Then, the Gaussian scale space of the image is constructed, and the categorized contrast features between the original image and the Gaussian scale space images are calculated to express the blur degree of different image contents. To simulate the impact of viewing distance on blur distortion, the distribution characteristics of local maximum gradient of multi-resolution images were also calculated in the spatial domain. Finally, the image blur assessment model is obtained by fusing all features and learning the mapping from features to quality scores by support vector regression (SVR). Performance of the proposed method is evaluated on four synthetically blurred databases and one real blurred database. The experimental results demonstrate that our method can produce quality scores more consistent with subjective evaluations than other methods, especially for real burred images.

Content-based Image Retrieval Using HSI Color Space and Neural Networks (HSI 컬러 공간과 신경망을 이용한 내용 기반 이미지 검색)

  • Kim, Kwang-Baek;Woo, Young-Woon
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.5 no.2
    • /
    • pp.152-157
    • /
    • 2010
  • The development of computer and internet has introduced various types of media - such as, image, audio, video, and voice - to the traditional text-based information. However, most of the information retrieval systems are based only on text, which results in the absence of ability to use available information. By utilizing the available media, one can improve the performance of search system, which is commonly called content-based retrieval and content-based image retrieval system specifically tries to incorporate the analysis of images into search systems. In this paper, a content-based image retrieval system using HSI color space, ART2 algorithm, and SOM algorithm is introduced. First, images are analyzed in the HSI color space to generate several sets of features describing the images and an SOM algorithm is used to provide candidates of training features to a user. The features that are selected by a user are fed to the training part of a search system, which uses an ART2 algorithm. The proposed system can handle the case in which an image belongs to several groups and showed better performance than other systems.

Spatial Analysis by Matching Methods using Elevation data of Aerophoto and LIDAR (항공사진과 LIDAR 표고 데이터의 매칭 기법에 의한 공간정보 분석 연구)

  • Yeon, sang-ho;Lee, Young-wook
    • Proceedings of the Korea Contents Association Conference
    • /
    • 2008.05a
    • /
    • pp.449-452
    • /
    • 2008
  • The building heights of big cities which charged with most space are 3-D information as relative vertical distance from ground control points, but they didn't know the heights using contour with maps as lose of skyline or building heights for downtown, practically continuously developed of many technology methods for implementation of 3-D spatial earth. So, For the view as stereos of variety earth form generated 3-D spatial and made terrain perspective map, 3-D simulated of regional and urban space as aviation images. In this papers, it composited geospatial informations and images by DEM generation, and developed and presented for techniques overlay of CAD data and photos captured at our surroundings uses. Particularly, The airborne LiDAR surveying which are very interesting trend have laser scanning sensor and determine the ground heights through detecting angle and range to the grounds, and then designated 3-D spatial composite and simulation from urban areas. Therefore in this papers are suggested ease selections on the users situation by compare as various simulations that its generation of 3-D spatial image by collective for downtown space and urban sub, and the implementation methods for more accurate, more select for the best images.

  • PDF

Comparison of dental radiography and computed tomography: measurement of dentoalveolar structures in healthy, small-sized dogs and cats

  • Lee, Seunghee;Lee, Kichang;Kim, Hyeona;An, Jeongsu;Han, Junho;Lee, Taekwon;Jeong, Hogyun;Cho, Youngkwon
    • Journal of Veterinary Science
    • /
    • v.21 no.5
    • /
    • pp.75.1-75.8
    • /
    • 2020
  • Background: Dental diseases are common in dogs and cats, and accurate measurements of dentoalveolar structure are important for planning of treatment. The information that the comparison computed tomography (CT) with dental radiography (DTR) is not yet reported in veterinary medicine. Objectives: The purpose of this study was to compare the DTR with CT of dentoalveolar structures in healthy dogs and cats, and to evaluate the CT images of 2 different slice thicknesses (0.5 and 1.0 mm). Methods: We included 6 dogs (2 Maltese and 1 Spitz, Beagle, Pomeranian, mixed, 1 to 8 years, 4 castrated males, and 2 spayed female) and 6 cats (6 domestic short hair, 8 months to 3 years, 4 castrated male, and 2 spayed female) in this study. We measured the pulp cavity to tooth width ratio (P/T ratio) and periodontal space of maxillary and mandibular canine teeth, maxillary fourth premolar, mandibular first molar, maxillary third premolar and mandibular fourth premolar. Results: P/T ratio and periodontal space in the overall dentition of both dogs and cats were smaller in DTR compared to CT. In addition, CT images at 1.0 mm slice thickness was generally measured to be greater than the images at 0.5 mm slice thickness. Conclusions: The results indicate that CT with thin slice thickness provides more accurate information on the dentoalveolar structures. Additional DTR, therefore, may not be required for evaluating dental structure in small-sized dogs and cats.

Joint Space Analysis Using Cone-beam Computed Tomography Imaging in Patients Diagnosed with Temporomandibular Joint Osteoarthritis and Occlusal Changes

  • Hyun-Jeong Park;Yo-Seob Seo;Jong-Won Kim;Sun-Kyoung Yu;Ji-Won Ryu
    • Journal of Oral Medicine and Pain
    • /
    • v.48 no.4
    • /
    • pp.152-158
    • /
    • 2023
  • Purpose: This pilot study aimed to evaluate changes in joint space (JS) using cone-beam computed tomography (CBCT) images of patients diagnosed with temporomandibular joint (TMJ) osteoarthritis (OA) and to determine the association between occlusal changes and JS. Methods: CBCT images were used to measure the anterior, superior, and posterior JSs of the sagittal plane. The differences in JS values over time and between groups were compared. The percentage change in the anteroposterior position of the mandibular condyle between groups was also analyzed. Results: Thirty-four subjects (mean age=43.91±20.13), comprising eight males (23.5%) and 26 females (76.5%), were divided into 18 patients with no change in occlusion (NCO) and 16 patients with a change in occlusion (CO) during TMJ OA. The JS measurements of the study subjects showed a decrease in anterior joint space (AJS) values over time. There was no difference in JS measurements between the groups at T1 and T2. AJS values measured at T1 were lower in the CO group than in the NCO group, but the difference was not statistically significant. In both groups, a posterior position of the mandibular condyle was initially observed with high frequency. However, there is a statistically significant difference in CBCT images taken after occlusal changes, with an increased frequency of condyles observed in the anterior or central positions. Conclusions: In conclusion, AJS decreased over time in TMJ OA, and the mandibular condyle became more anteriorly positioned with occlusal changes. Therefore, clinicians should diligently monitor mandibular condyle morphology and JS using CBCT, along with the patient's clinical symptoms, to treat and control TMJ OA effectively.

Radiological Findings and Treatment Period of Acute Low Back Pain Patients Diagnosed as Having Lumbar Sprain and Strain - with Focus on X-ray and CT Findings - (요천추부 염좌로 진단된 급성 요통 환자의 방사선학적 소견과 치료기간에 대한 임상적 고찰 - X-ray와 CT 소견 분석 -)

  • Koh, Pil-Seong;Yi, Won-Il;Joh, Byung-Jin;Kwon, Sin-Ae;Lee, Jung-Woo;Kim, Min-Jung;Seo, Byung-Kwan;Woo, Hyun-Soo;Baek, Yong-Hyun;Kim, Jae-Kyu;Park, Dong-Suk
    • Journal of Acupuncture Research
    • /
    • v.27 no.4
    • /
    • pp.19-28
    • /
    • 2010
  • Objectives : To demonstrate the need for differential diagnosis between discogenic pain and lumbar sprain and strain in acute low-back pain patients. Methods : Outpatients who made their first visits during May 1, 2009 to Oct. 30, 2009(n=53) were examined by history taking, physical examination, X-rays, and CT imaging. Disorders found on lumbosacral spine X-ray cuts and those on lumbosacral spine CT images were separately recorded. The relationship between treatment period, disc space narrowing and disc degeneration on X-rays, and HIVD on CT images was examined. Results : 1. Correlation between disc space narrowing on X-rays and HIVD found on CT images was analyzed. 21(72.41%) out of 29 patients having disc space narrowing on X-rays and HIVD on CT at the same level required treatment for over 8 weeks. 2. 2(50%) out of 4 Lawrence classification grade I patients, 8(66.67%) out of 12 grade II patients, and 14(70%) out of 20 grade III patients needed treatment for over 8 weeks. Conclusions : Disc space narrowing on X-ray and HIVD on CT at the same level, or disc space narrowing and disc degeneration on X-ray image alone indicate a tendency for treatment periods over 8 weeks, which is longer than the conventional treatment period for lumbar strain and sprain.