• Title/Summary/Keyword: positional field

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Temperature distribution in VX-2 hepatoma heated with thermoseed hyperthermia (열소자 온열요법시 VX-2 hepatoma내의 온도 변화에 대한 연구)

  • Choi, Ihl-Bohng;Bahk, Yong-Whee
    • Radiation Oncology Journal
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    • v.12 no.3
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    • pp.295-300
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    • 1994
  • It was the purpose of present study to develop a new thermoseed for heating deep-seated tumors and assessment of the effect of magnetic control on thermoseeds. Aqueous suspension of iron micro spheres (Ferropolysaccharide) was injected directly into the VX-2 hepatoma and heated with 1.2 MHz inductive radiofrequency unit. Aqueous thermoseed suspension was delivered to the tumor by simple percutaneous injection. The limitation of the thermoseed heating method is the positional change of thermoseed particles in the tumor after implantation. The thermoseed particles could enter the systemic blood circulation and cause a severe embolization of a critical organ. To minimize this limitation, we have used the magnetic control after loading the thermoseed in the tumor, W hen ferropolysaccharides were exposed to a strong magnetic field, they magnetized and subsequently exerted a magnetic force on each other, forming larger aggregates of particles. The size of aggregated Particles were too big to enter the systemic blood circulation. Thus, unlike other thermoseed method, we hold the thermoseed particles stationary in the tumor. The temperature of the injected site and immediate vicinity elevated by $4-5^{\circ}C$. The temperature of the surrounding normal hepatic tissue elevated by $1-2^{circ}C$ only. The heating effect within the tumor was variable depending on the density of ferromagnetic aqueous suspension. Our results suggest that inductive heating of tumor injected with ferropolysaccharide solution offers the possibility of effective heat delivery to the defined tumor volume, which is difficult to heat with other heating devices.

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Automatic Generation of GCP Chips from High Resolution Images using SUSAN Algorithms

  • Um Yong-Jo;Kim Moon-Gyu;Kim Taejung;Cho Seong-Ik
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.220-223
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    • 2004
  • Automatic image registration is an essential element of remote sensing because remote sensing system generates enormous amount of data, which are multiple observations of the same features at different times and by different sensor. The general process of automatic image registration includes three steps: 1) The extraction of features to be used in the matching process, 2) the feature matching strategy and accurate matching process, 3) the resampling of the data based on the correspondence computed from matched feature. For step 2) and 3), we have developed an algorithms for automated registration of satellite images with RANSAC(Random Sample Consensus) in success. However, for step 1), There still remains human operation to generate GCP Chips, which is time consuming, laborious and expensive process. The main idea of this research is that we are able to automatically generate GCP chips with comer detection algorithms without GPS survey and human interventions if we have systematic corrected satellite image within adaptable positional accuracy. In this research, we use SUSAN(Smallest Univalue Segment Assimilating Nucleus) algorithm in order to detect the comer. SUSAN algorithm is known as the best robust algorithms for comer detection in the field of compute vision. However, there are so many comers in high-resolution images so that we need to reduce the comer points from SUSAN algorithms to overcome redundancy. In experiment, we automatically generate GCP chips from IKONOS images with geo level using SUSAN algorithms. Then we extract reference coordinate from IKONOS images and DEM data and filter the comer points using texture analysis. At last, we apply automatically collected GCP chips by proposed method and the GCP by operator to in-house automatic precision correction algorithms. The compared result will be presented to show the GCP quality.

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Accuracy Analysis of Image Orientation Technique and Direct Georeferencing Technique

  • Bae Sang-Keun;Kim Byung-Guk
    • Spatial Information Research
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    • v.13 no.4 s.35
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    • pp.373-380
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    • 2005
  • Mobile Mapping Systems are effective systems to acquire the position and image data using vehicle equipped with the GPS (Global Positioning System), IMU (Inertial Measurement Unit), and CCD camera. They are used in various fields of road facility management, map update, and etc. In the general photogrammetry such as aerial photogrammetry, GCP (Ground Control Point)s are needed to compute the image exterior orientation elements (the position and attitude of camera). These points are measured by field survey at the time of data acquisition. But it costs much time and money. Moreover, it is not possible to make sufficient GCP as much as we want. However Mobile Mapping Systems are more efficient both in time and money because they can obtain the position and attitude of camera at the time of photographing. That is, Image Orientation Technique must use GCP to compute the image exterior orientation elements, but on the other hand Direct Georeferencing can directly compute the image exterior orientation elements by GPS/INS. In this paper, we analyze about the positional accuracy comparison of ground point using the Image Orientation Technique and Direct Georeferencing Technique.

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Minimizing Redundant Route Nodes in USN by Integrating Spatially Weighted Parameters: Case Study for University Campus (가중치가 부여된 공간변수에 의거하여 USN 루트노드 최소화 방안 -대학 캠퍼스를 사례로-)

  • Kim, Jin-Taek;Um, Jung-Sup
    • Journal of the Korean Geographical Society
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    • v.45 no.6
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    • pp.788-805
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    • 2010
  • The present USN (Ubiquitous Sensor Networks) node deployment practices have many limitations in terms of positional connectivity. The aim of this research was to minimize a redundancy of USN route nodes, by integrating spatially weighted parameters such as visibility, proximity to cell center, road density, building density and cell overlapping ratio into a comprehensive GIS database. This spatially weighted approach made it possible to reduce the number of route nodes (11) required in the study site as compared to that of the grid network method (24). The field test for RSSI (Received Signal Strength Indicator) indicates that the spatially weighted deployment could comply with the quality assurance standard for node connectivity, and that reduced route nodes do not show a significant degree of signal fluctuation for different site conditions. This study demonstrated that the spatially weighted deployment can be used to minimize a redundancy of USN route nodes in a routine manner, and the quantitative evidence removing a redundancy of USN route nodes could be utilized as major tools to ensure the strong signal in the USN, that is frequently encountered in real applications.

Anatomical study of the location of the antilingula, lingula, and mandibular foramen for vertical ramus osteotomy

  • Park, Jin Hoo;Jung, Hwi-Dong;Kim, Hyung Jun;Jung, Young-Soo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.40
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    • pp.15.1-15.6
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    • 2018
  • Background: The purpose of this study was to identify the location of the antilingula, lingula, and mandibular foramen in Korean cadavers and to promote safe and accurate surgery without damage to the inferior alveolar neurovascular bundle (IANB) when performing a vertical ramus osteotomy (VRO). Methods: This study was conducted on the dried mandibles of 20 adult cadavers. Digital calipers were used to measure the distances from the anatomical reference points (antilingula, lingula, and mandibular foramen). Result: The antilingula was located at the anterior 44% and superior 31% in the ramus. The lingula was located at the anterior 55% and superior 30% in the ramus. The mandibular foramen was located at the anterior 58% and superior 46% in the ramus. Regarding the positional relationship with the antilingula, the lingula was located 0.54 mm superior and 4.19 mm posterior, and the mandibular foramen was located 6.95 mm inferior and 4.98 mm posterior. The results suggested that in order to prevent damage to the IANB, osteotomy should be performed in the posterior region of ramus at least 29% of the total horizontal length of the ramus. Conclusion: Using only the antilingula as a reference point is not guaranteed to IANB injury. However, it is still important as a helpful reference point for the surgeon in the surgical field.

Development of Network-Based Online GPS Baseline Processing System (네트워크 기반 온라인 GPS 기선해석 시스템 개발)

  • Kim, Su-Kyung;Bae, Tae-Suk
    • Journal of the Korean Association of Geographic Information Studies
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    • v.14 no.2
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    • pp.138-146
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    • 2011
  • With the increased use of GPS in the field of various applications including surveying, the request for fast and precise positional information has increased. Several countries such as USA, Canada, and Australia have already been operating Internet-based automatic GPS data analysis system using e-mail and FTP. Expanding GPS market, it is necessary to establish automatic GPS baseline processing system that is accessible via Internet. The system developed in this study is operating on the web, and it allows the users to access easily regardless of time and place. The main processing engines are Bernese V5.0 and PAGES. They process user data with three GPS CORS(Continuously Operating Reference Station), and then send the report to the users through e-mail. This system allows users to process high accurate GPS data easily. It is expected that this system will be used for various GPS applications such as monitoring large-scale structures and providing spatial information services in private sector.

Super-resolution Reconstruction Method for Plenoptic Images based on Reliability of Disparity (시차의 신뢰도를 이용한 플렌옵틱 영상의 초고해상도 복원 방법)

  • Jeong, Min-Chang;Kim, Song-Ran;Kang, Hyun-Soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.22 no.3
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    • pp.425-433
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    • 2018
  • In this paper, we propose a super-resolution reconstruction algorithm for plenoptic images based on the reliability of disparity. The subperture image generated by the Flanoptic camera image is used for disparity estimation and reconstruction of super-resolution image based on TV_L1 algorithm. In particular, the proposed image reconstruction method is effective in the boundary region where disparity may be relatively inaccurate. The determination of reliability of disparity vector is based on the upper, lower, left and right positional relationship of the sub-aperture image. In our method, the unreliable vectors are excluded in reconstruction. The performance of the proposed method was evaluated by comparing to a bicubic interpolation method, a conventional disparity based method and dictionary based method. The experimental results show that the proposed method provides the best performance in terms of PSNR(Peak Signal to noise ratio), SSIM(Structural Similarity).

A Study on Position Matching Technique for 3D Building Model using Existing Spatial Data - Focusing on ICP Algorithm Implementation - (기구축 공간데이터를 활용한 3차원 건물모델의 위치정합 기법 연구 - ICP 알고리즘 구현 중심으로 -)

  • Lee, Jaehee;Lee, Insu;Kang, Jihun
    • Journal of Cadastre & Land InformatiX
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    • v.51 no.1
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    • pp.67-77
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    • 2021
  • Spatial data is becoming very important as a medium that connects various data produced in smart cities, digital twins, autonomous driving, smart construction, and other applications. In addition, the rapid construction and update of spatial information is becoming a hot topic to satisfy the diverse needs of consumers in this field. This study developed a software prototype that can match the position of an image-based 3D building model produced without Ground Control Points using existing spatial data. As a result of applying this software to the test area, the 3D building model produced based on the image and the existing spatial data show a high positional matching rate, so that it can be widely used in applications requiring the latest 3D spatial data.

ANALYSIS OF THE USAGE OF NAM BYEONG-CHEOL'S ARMILLARY SPHERE IN UIGIJIPSEOL IN THE 19TH CENTURY (19세기 남병철 『의기집설(儀器輯說)』 혼천의 용법 분석)

  • HONG SOON CHOI;SANG HYUK KIM;BYEONG-HEE MIHN;KYOUNG-UK NAM;GEOYOUNG-HAN YOO;YONGGI KIM
    • Publications of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.13-26
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    • 2024
  • The armillary sphere, an astronomical observation device embodying the Orbital Heaven Theory of the Later Han Dynasty in China, holds both historical and scientific significance. It has been produced in various forms by many individuals since its inception in the era of King Sejong in the Joseon Dynasty. A prominent figure in this field was Nam Byeong-cheol (南秉哲, 1817-1863), known for his work 'Uigijipseol' (儀器輯說), published in 1859, which detailed the history, production methods, and usage of the armillary sphere. This text particularly highlights 21 applications of the armillary sphere, divided into 33 measurements, covering aspects like installation, time, and positional measurements, supplemented with explanations of spherical trigonometry. Despite numerous records of the armillary sphere's design during the Joseon Dynasty, detailed usage information remains scarce. In this study, the 33 measurements described in 'Uigijipseol' (儀器輯說) were systematically classified into six for installation, nineteen for position measurement, seven for time measurement, and one for other purposes. Additionally, the measurement methods were analyzed and organized by dividing them into the ecliptic ring, moving equatorial ring, and fixed equatorial ring of the armillary sphere. In other words, from a modern astronomical perspective, the results of schematization for each step were presented by analyzing it from the viewpoint of longitude, right ascension, and solar time. Through the analysis of Nam's armillary sphere, this study not only aims to validate the restoration model of the armillary sphere but also suggests the potential for its use in basic astronomical education based on the understanding of the 19th-century Joseon armillary sphere.

Automated Construction Progress Management Using Computer Vision-based CNN Model and BIM (이미지 기반 기계 학습과 BIM을 활용한 자동화된 시공 진도 관리 - 합성곱 신경망 모델(CNN)과 실내측위기술, 4D BIM을 기반으로 -)

  • Rho, Juhee;Park, Moonseo;Lee, Hyun-Soo
    • Korean Journal of Construction Engineering and Management
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    • v.21 no.5
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    • pp.11-19
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    • 2020
  • A daily progress monitoring and further schedule management of a construction project have a significant impact on the construction manager's decision making in schedule change and controlling field operation. However, a current site monitoring method highly relies on the manually recorded daily-log book by the person in charge of the work. For this reason, it is difficult to take a detached view and sometimes human error such as omission of contents may occur. In order to resolve these problems, previous researches have developed automated site monitoring method with the object recognition-based visualization or BIM data creation. Despite of the research results along with the related technology development, there are limitations in application targeting the practical construction projects due to the constraints in the experimental methods that assume the fixed equipment at a specific location. To overcome these limitations, some smart devices carried by the field workers can be employed as a medium for data creation. Specifically, the extracted information from the site picture by object recognition technology of CNN model, and positional information by GIPS are applied to update 4D BIM data. A standard CNN model is developed and BIM data modification experiments are conducted with the collected data to validate the research suggestion. Based on the experimental results, it is confirmed that the methods and performance are applicable to the construction site management and further it is expected to contribute speedy and precise data creation with the application of automated progress monitoring methods.