• Title/Summary/Keyword: imaging techniques

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A New True Ortho-photo Generation Algorithm for High Resolution Satellite Imagery

  • Bang, Ki-In;Kim, Chang-Jae
    • Korean Journal of Remote Sensing
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    • v.26 no.3
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    • pp.347-359
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    • 2010
  • Ortho-photos provide valuable spatial and spectral information for various Geographic Information System (GIS) and mapping applications. The absence of relief displacement and the uniform scale in ortho-photos enable interested users to measure distances, compute areas, derive geographic locations, and quantify changes. Differential rectification has traditionally been used for ortho-photo generation. However, differential rectification produces serious problems (in the form of ghost images) when dealing with large scale imagery over urban areas. To avoid these artifacts, true ortho-photo generation techniques have been devised to remove ghost images through visibility analysis and occlusion detection. So far, the Z-buffer method has been one of the most popular methods for true ortho-photo generation. However, it is quite sensitive to the relationship between the cell size of the Digital Surface Model (DSM) and the Ground Sampling Distance (GSD) of the imaging sensor. Another critical issue of true ortho-photo generation using high resolution satellite imagery is the scan line search. In other words, the perspective center corresponding to each ground point should be identified since we are dealing with a line camera. This paper introduces alternative methodology for true ortho-photo generation that circumvents the drawbacks of the Z-buffer technique and the existing scan line search methods. The experiments using real data are carried out while comparing the performance of the proposed and the existing methods through qualitative and quantitative evaluations and computational efficiency. The experimental analysis proved that the proposed method provided the best success ratio of the occlusion detection and had reasonable processing time compared to all other true ortho-photo generation methods tested in this paper.

Inhibitory Effect of Ginsenosides on NMDA Receptor-mediated Signals in Rat Hippocampal Neurons

  • Kim Sunoh;Choo Min-Kyung;Nah Seung-Yeol;Kim Dong-Hyun;Rhim Hyewhon
    • Proceedings of the Ginseng society Conference
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    • 2002.10a
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    • pp.531-544
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    • 2002
  • Ginseng is the best known and most popular herbal medicine used worldwide. Ameliorating effects of ginseng were observed on the models of scopolamine-induced, aged or hippocampal lesioned learning and memory deficits. Further beneficial effects of ginseng were observed on neuronal cell death associated with ischemia or glutamate toxicity. In spite of these beneficial effects of ginseng on the CNS, little scientific evidence shows at the cellular level. In the present study, we have employed cultures of rat hippocampal neurons and examined the direct modulation of ginseng on NMDA receptor-induced changes in $[Ca^{2+}]_i$ and -gated currents using fura-2-based digital imaging and perforated whole-cell patch-clamp techniques, respectively. We found that ginseng total saponins inhibited NMDA-induced but less effectively glutamate-induced increase in $[Ca^{2+}]_i$ Ginseng total saponins also modulated $Ca^{2+}$ transients evoked by depolarization with 50 mM KCI along with its own effects on $[Ca^{2+}]_i$. Among ginsenosides tested, ginsenoside $Rg_3$ was found to be the most potent component for ginseng actions on NMDA receptors. Furthermore, we examined the inhibitory effects ofbiotransformants of ginsenosides on NMDA receptor using purified stereoisomers of ginsenosides. 20(S)-ginsenoside $Rg_3$ and its metabolite, 20(S)-ginsenoside $Rh_3$, produced the strongest inhibition while 20(S)-ginsenoside $Rh_1$ and Compound K produced the moderate inhibition on NMDA-induced increase in $[Ca^{2+}]_i$. The data obtained suggest that the inhibition of NMDA receptors by ginseng, in particular by 20(S)-ginsenoside $Rg_3$ and its metabolite, 20(S)-ginsenoside $Rh_2$, could be one of mechanisms for ginsengmediated neuroprotective actions.

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Android-Based Open Platform Intelligent Vehicle Services Middleware Application (안드로이드 기반의 지능형자동차 미들웨어 오픈플랫폼 서비스 응용)

  • Choi, Byung-Kwan
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.8
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    • pp.33-41
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    • 2013
  • Intelligent automobile technology and IT convergence, the development of new imaging technology media applications based on open source Android installed on tracked, wheeled smart phone application technology and the development of intelligent vehicles as a new paradigm a lot of research and development being made. Android-based intelligent automotive applications, technology, and evolved into the center of a set of various multimedia technologies move beyond the limits of the means of each of multimedia platforms, services and applications that have been developed in such a distributed environment, has been developed according to a variety of services through technology mobile terminal device technology is an absolute requirement. In this paper, SVC Codec, real-time video and graphics processing and SoC design intelligent vehicles middleware applications with monolithic system specification through Android-based design of intelligent vehicles dedicated middleware research experiments on open platforms, and provides various terminal services functions SoC based on a newly designed and standardized interface analysis techniques in this study were verified through experiments.

ELECTRICAL RESISTANCE IMAGING OF TWO-PHASE FLOW WITH A MESH GROUPING TECHNIQUE BASED ON PARTICLE SWARM OPTIMIZATION

  • Lee, Bo An;Kim, Bong Seok;Ko, Min Seok;Kim, Kyung Youn;Kim, Sin
    • Nuclear Engineering and Technology
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    • v.46 no.1
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    • pp.109-116
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    • 2014
  • An electrical resistance tomography (ERT) technique combining the particle swarm optimization (PSO) algorithm with the Gauss-Newton method is applied to the visualization of two-phase flows. In the ERT, the electrical conductivity distribution, namely the conductivity values of pixels (numerical meshes) comprising the domain in the context of a numerical image reconstruction algorithm, is estimated with the known injected currents through the electrodes attached on the domain boundary and the measured potentials on those electrodes. In spite of many favorable characteristics of ERT such as no radiation, low cost, and high temporal resolution compared to other tomography techniques, one of the major drawbacks of ERT is low spatial resolution due to the inherent ill-posedness of conventional image reconstruction algorithms. In fact, the number of known data is much less than that of the unknowns (meshes). Recalling that binary mixtures like two-phase flows consist of only two substances with distinct electrical conductivities, this work adopts the PSO algorithm for mesh grouping to reduce the number of unknowns. In order to verify the enhanced performance of the proposed method, several numerical tests are performed. The comparison between the proposed algorithm and conventional Gauss-Newton method shows significant improvements in the quality of reconstructed images.

Description of a novel ultrasound guided peribulbar block in horses: a cadaveric study

  • Leigh, Hannah;Gozalo-Marcilla, Miguel;Esteve, Vicente;Bautista, Alvaro Jesus Gutierrez;Gimenez, Tamara Martin;Viscasillas, Jaime
    • Journal of Veterinary Science
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    • v.22 no.2
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    • pp.22.1-22.9
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    • 2021
  • Background: Standing surgery in horses combining intravenous sedatives, analgesics and local anaesthesia is becoming more popular. Ultrasound guided (USG) peribulbar nerve block (PB) has been described in dogs and humans for facial and ocular surgery, reducing the risk of complications versus retrobulbar nerve block (RB). Objective: To describe a technique for USG PB in horse cadavers. Methods: Landmarks and PB technique were described in two equine cadaver heads (Phase 1), with computed tomography (CT) imaging confirming contrast location and spread. In Phase 2, ten equine cadaver heads were randomised to two operators naive to the USG PB, with moderate experience with ultrasonography and conventional "blind" RB. Both techniques were demonstrated once. Subsequently, operators performed five USG PB and five RB each, unassisted. Contrast location and spread were evaluated by CT. Injection site success was defined for USG PB as extraconal contrast, and for RB intraconal contrast. Results: Success was 10/10 for USG PB and 0/10 for RB (p < 0.001). Of the RB injections, eight resulted in extraconal contrast and two in the masseter muscle (p = 0.47). Conclusions: The USG PB had a high injection site success rate compared with the RB technique; however, we cannot comment on clinical effect. The USG technique was easily learnt, and no potential complications were seen. The USG PB nerve block could have a wide application for use in horses for ocular surgeries (enucleations, eyelid, corneal, cataract surgeries, and ocular analgesia) due to reduced risk of iatrogenic damage. Further clinical studies are needed.

The Effect of Teacher Participation-Oriented Education Program Centered on Multi-Faceted Analysis of Elementary Science Classes on the Class Expertise of Novice Teacher (초등 과학수업의 다면적 분석을 중심으로 한 교사 참여형 교육프로그램이 초보교사의 수업전문성에 미치는 효과)

  • Shin, Won-Sub;Shin, Dong-Hoon
    • Journal of Korean Elementary Science Education
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    • v.38 no.3
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    • pp.406-425
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    • 2019
  • The purpose of this study is to analyze The Effect of Teacher Participation-oriented Education Program (TPEP) centered on Multi-Faceted Analysis of Elementary Science Classes on the Class Expertise of novice teacher. First, in order to develop the TPEP, lectures and exploratory science classes were analyzed using imaging and eye-tracking techniques. In this study, the TPEP was developed in five stages: image analysis, eye analysis, teaching language analysis, gesture analysis, and class development. Participants directly analyzed the classes of experienced and novice teachers at each stage. The TPEP developed in this study is different from the existing teacher education program in that it reflected the human performance technology aspects. The participants analyzed actual elementary science classes in a multi-faceted way and developed better classes based on them. The results of this study are as follows. First, at the teacher training institutions and the school sites, pre-service teachers and novice teachers should be provided with various experiences in class analysis and multi-faceted analysis of their own classes. Second, through this study, we were able to identify the limitations of existing class observations and video analysis. Third, the TPEP should be developed to improve the novice teachers' class expertise. Finally, we hope that the results of this study are used as basic data in developing programs to improve teachers' class expertise in teacher training institutions and education policy institutions.

Does the Use of Injectable Atelocollagen during Arthroscopic Rotator Cuff Repair Improve Clinical and Structural Outcomes?

  • Kim, In Bo;Kim, Eun Yeol;Lim, Kuk Pil;Heo, Ki Seong
    • Clinics in Shoulder and Elbow
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    • v.22 no.4
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    • pp.183-189
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    • 2019
  • Background: Since the establishment of biological augmentation to improve the treatment of rotator cuff tears, it is imperative to explore newer techniques to reduce the retear rate and improve long-term shoulder function after rotator cuff repair. This study was undertaken to determine the consequences of a gel-type atelocollagen injection during arthroscopic rotator cuff repair on clinical outcomes, and evaluate its effect on structural integrity. Methods: Between January 2014 and June 2015, 121 patients with full thickness rotator cuff tears underwent arthroscopic rotator cuff repair. Of these, 61 patients were subjected to arthroscopic rotator cuff repair in combination with an atelocollagen injection (group I), and 60 patients underwent arthroscopic rotator cuff repair alone (group II). The visual analogue scale (VAS) for pain and the Korean Shoulder Society (KSS) scores were evaluated preoperatively and postoperatively. Magnetic resonance imaging (MRI) was performed at 6 months postoperatively, to assess the integrity of the repair. Results: VAS scores were significantly lower in group I than in group II at 3, 7, and 14 days after surgery. KSS scores showed no significant difference between groups in the 24 months period of follow-up. No significant difference was obtained in the healing rate of the rotator cuff tear at 6 months postoperatively (p=0.529). Conclusions: Although a gel-type atelocollagen injection results in reduced pain in patients at 2 weeks after surgery, our study does not substantiate the administration of atelocollagen during rotator cuff repair to improve the clinical outcomes and healing of the rotator cuff.

Bone changes in the mandibular incisors after orthodontic correction of dental crowding without extraction: A cone-beam computed tomographic evaluation

  • Valerio, Claudia Scigliano;Cardoso, Claudia Assuncao e Alves;Arauujo, Eustaquio Afonso;Zenobio, Elton Goncalves;Manzi, Flavio Ricardo
    • Imaging Science in Dentistry
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    • v.51 no.2
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    • pp.155-165
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    • 2021
  • Purpose: This study aimed to evaluate changes of the alveolar bone and interdental bone septum of the mandibular incisors through cone-beam computed tomography (CBCT) after orthodontic treatment of mandibular dental crowding without dental extraction. Materials and Methods: The sample consisted of 64 CBCT images(32 pre-treatment and 32 post-treatment) from 32 adult patients with class I malocclusion and an average age of 23.0±3.9 years. The width and height of the alveolar bone and interdental septum, the distance between the cementoenamel junction (CEJ) and the facial and lingual bone crests, and the inclination of the mandibular incisors were measured. Results: The distance between the CEJ and the marginal bone crest on the facial side increased significantly (P<0.05). An increased distance between the CEJ and the bone crest on the facial and lingual sides showed a correlation with the irregularity index (P<0.05); however, no significant association was observed with increasing mandibular incisor inclination (P>0.05). The change in the distance between the CEJ and the marginal bone crest on the facial side was correlated significantly with bone septum height(P<0.05). Conclusion: Bone dehiscence developed during the treatment of crowding without extraction only on the incisors' facial side. Increasing proclination of the mandibular incisor was not correlated with bone dehiscence. The degree of dental crowding assessed through the irregularity index was associated with the risk of developing bone dehiscence. The interdental septum reflected facial marginal bone loss in the mandibular incisors.

Morphometric analysis of the inter-mastoid triangle for sex determination: Application of statistical shape analysis

  • Sobhani, Farshad;Salemi, Fatemeh;Miresmaeili, Amirfarhang;Farhadian, Maryam
    • Imaging Science in Dentistry
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    • v.51 no.2
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    • pp.167-174
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    • 2021
  • Purpose: Sex determination can be done by morphological analysis of different parts of the body. The mastoid region, with its anatomical location at the skull base, is ideal for sex identification. Statistical shape analysis provides a simultaneous comparison of geometric information on different shapes in terms of size and shape features. This study aimed to investigate the geometric morphometry of the inter-mastoid triangle as a tool for sex determination in the Iranian population. Materials and Methods: The coordinates of 5 landmarks on the mastoid process on the 80 cone-beam computed tomographic images(from individuals aged 17-70 years, 52.5% female) were registered and digitalized. The Cartesian x-y coordinates were acquired for all landmarks, and the shape information was extracted from the principal component scores of generalized Procrustes fit. The t-test was used to compare centroid size. Cross-validated discriminant analysis was used for sex determination. The significance level for all tests was set at 0.05. Results: There was a significant difference in the mastoid size and shape between males and females(P<0.05). The first 2 components of the Procrustes shape coordinates explained 91.3% of the shape variation between the sexes. The accuracy of the discriminant model for sex determination was 88.8%. Conclusion: The application of morphometric geometric techniques will significantly impact forensic studies by providing a comprehensive analysis of differences in biological forms. The results demonstrated that statistical shape analysis can be used as a powerful tool for sex determination based on a morphometric analysis of the inter-mastoid triangle.

Direction detection technique of radioactive contaminants based on rotating collimator (회전형 콜리메이터 기반 방사능 오염원의 방향탐지 기법)

  • Hwang, Young-Gwan;Song, Keun-Young;Lee, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.11
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    • pp.1519-1527
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    • 2020
  • AGeneral radiation measuring devices have been developed in the form of spatial dose rate detection devices that measure dose rates to radioactive contaminant and 2D or 3D imaging devices for radioactive contamination information. Each of these radiation detection techniques has advantages. The advantages of both detection devices are necessary to minimize personal injury and rapid decontamination in the area of a radioactive accident. In this paper, we proposed a technique that can measure the dose rate and direction information about the radioactive pollutant source in real time using a detection sensor, a rotating body, and a directional shield for radioactive pollutant detection. The rotational-based detection device is configured to check the dose rate and direction using the location information of the rotator and measurement value. We proposed a measurement technique for vertical and horizontal directions through multiple holes. It was confirmed that the measurement error for direction information was less than 1% when detected in the horizontal direction.