• Title/Summary/Keyword: time resolution

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Four Dimension(4D) Time Resolved Imaging of Contrast Kinetics(TRICKS) MR Angiography (4차원 영상기법 Time Resolved Imaging of Contrast Kinetics MRA의 유용성)

  • Lim, cheong-hwan;Bae, sung-jin
    • Proceedings of the Korea Contents Association Conference
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    • 2009.05a
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    • pp.1105-1110
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    • 2009
  • To assess the clinical value of time resolved imaging of contrast kinetics(TRICKS) MRA by comparison with conventional time of flight(TOF) MR angiography. Both TOF-MRA and TRICKS-MRA were performed in 17 patients with cerebrovascular disease and in 6 patients with brain tumor. Among 17 cerebraovascular patients, digital subtraction angiography(DSA) data were also obtained in 11 patients. TOF-MRA showed good spatial resolution but short in temporal resolution. Although TRICKS-MRA showed somewhat low spatial resolution, it showed superior temporal resolution by distinguishing vessel and tumor in all patients. Also, from the analysis of vessel-tumor relationship, TRICKS-MRA showed better performance than TOF-MRA. TRICKS-MRA makes it possible to image arterial, capillary and venous phase sequentially with very speedy manner and therefore, the clinical use of this method is highly suggestive for future use.

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Implementation and Performance Evaluation of a Video-Equipped Real-Time Fire Detection Method at Different Resolutions using a GPU (GPU를 이용한 다양한 해상도의 비디오기반 실시간 화재감지 방법 구현 및 성능평가)

  • Shon, Dong-Koo;Kim, Cheol-Hong;Kim, Jong-Myon
    • Journal of the Korea Society of Computer and Information
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    • v.20 no.1
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    • pp.1-10
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    • 2015
  • In this paper, we propose an efficient parallel implementation method of a widely used complex four-stage fire detection algorithm using a graphics processing unit (GPU) to improve the performance of the algorithm and analyze the performance of the parallel implementation method. In addition, we use seven different resolution videos (QVGA, VGA, SVGA, XGA, SXGA+, UXGA, QXGA) as inputs of the four-stage fire detection algorithm. Moreover, we compare the performance of the GPU-based approach with that of the CPU implementation for each different resolution video. Experimental results using five different fire videos with seven different resolutions indicate that the execution time of the proposed GPU implementation outperforms that of the CPU implementation in terms of execution time and takes a 25.11ms per frame for the UXGA resolution video, satisfying real-time processing (30 frames per second, 30fps) of the fire detection algorithm.

High Resolution Frequency Estimation of Real Sinusoids (고분해능의 주파수 추정 알고리즘 개발)

  • Seo, In-Yong
    • Proceedings of the KIEE Conference
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    • 2003.10a
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    • pp.279-282
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    • 2003
  • In this paper, we propose a new high resolution frequency estimator for real sinusoids by using short time data and the AWLS/MFT (Adaptive Weighted Least Squares/ Modulation Function Technique) algorithm. Monte-Carlo simulations verify better performances of the proposed frequency estimator and demonstrate that the proposed AWLS sinusoidal estimator is a high resolution estimator.

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A Study on the Improvement a Lateral Resolution of the Ultrasound Imaging System (초음파 영상장치에서 측방향 해상도 향상에 관한 연구)

  • 이후정;이행세
    • Journal of Biomedical Engineering Research
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    • v.9 no.1
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    • pp.87-92
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    • 1988
  • In this paper, a new focusing method, to be called the pipelined sampled delay focusing (PSDF), is implemented. This method improves the lateral resolution in ultrasound imaging system. In PSDF, the analog belay lines are no longer necessary because sampling sum process can replace the conventional delay sum process. Also, the method offers continuous dynamic focusing on the resolution pixel basis, and eliminates the constraint that the maximum delay time is less than the sampling interval. Second order sampling is adopted in order to extend the sampling interval.

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A Study on the Propagation Characteristics along the Microstrip Lines using Wavelet Transforms (웨이브릿 변환을 이용한 마이크로스트립 선로에서의 전파 특성 연구)

  • 이재웅;송용원;김건욱;박한규
    • Proceedings of the IEEK Conference
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    • 1999.06a
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    • pp.223-226
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    • 1999
  • We study the propagation property of the transient signals along the microstrip using the wavelet transform. Wavelet transform can offer the time-frequency windows. It makes the resolution of time high in high frequency range and the resolution of frequency high in low frequency range. So It is useful to analyze the signals which have both low and high frequency components.

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UAV Conflict Detection and Resolution Based on Geometric Approach

  • Park, Jung-Woo;Oh, Hyon-Dong;Tahk, Min-Jea
    • International Journal of Aeronautical and Space Sciences
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    • v.10 no.1
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    • pp.37-45
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    • 2009
  • A method of conflict detection and resolution is described by using simple geometric approach. Two VAVs are dealt with and considered as point masses with constant velocity. This paper discusses en route aircraft which are assumed to be linked by real time data bases like ADS-B. With this data base, all DAVs share the information each other. Calculating PCA (Point of Closest Approach), we can evaluate the worst conflict condition between two VAVs. This paper proposes one resolution maneuvering logic, which can be called 'Vector Sharing Resolution'. In case of conflict, using miss distance vector in PCA, we can decide the directions for two VAVs to share the conflict region. With these directions, VAVs are going to maneuver cooperatively. First of all, this paper describes some '2-D' conflict scenarios and then extends to '3-D' conflict scenarios.

A STUDY ON THE DETERMINATION OF THE INSTANTANEOUS FIELD OF VIEW FOR I-M HIGH RESOLUTION SATELLITE IMAGE

  • Seo Doo-Chun;Park Su-Young;Lee Dong-Han;Lee Sun-Gu;Song Jeong Heon;Lim Hyo-Suk
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.649-652
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    • 2005
  • In this paper we present a detail approach of the determination of IFOV (Instantaneous Field of View) of high-resolution (l m) panchromatic satellite image over test site. IFOV is the representative measurements as the determination of the spatial resolution in remote sensed imaging system. It can be defined as some area on the ground with the particular altitude when the satellite acquires the image at any given time. Especially, spatial resolution of passive sensors primarily depends on their IFOV. The determination of IFOV goes through simple steps of procedure as followings: Firstly, the GSD (Ground Sample Distance) should be computed at each point on the geometrically corrected image. Then, The GSD is converted into the IFOV. So we are going to explain our test procedures and results.

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A STUDY OF THE RESOLUTION OF DENTAL INTRAORAL X-RAY MACHINES (치과 구내 X-선 촬영기의 사용연한에 따른 해상능에 관한 연구)

  • Kim Seon Ju;Chung Hyon De
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.20 no.2
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    • pp.289-297
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    • 1990
  • The purpose of this study was to assess the resolution and focal spot size of dental X-ray machines. Fifty dental X-ray machines were selected for measuring resolution and focal spot size. These machines were used in general dental clinics. The time of installation of the X-ray machine varies from 1 year to 10 years. The resolution of these machines was measured with the test pattern. The focal spot size of these machines was measured with the star test pattern. The following results were obtained: 1. The resolution of dental intraoral X-ray machines was not significantly changed in ten years. 2. The focal spot size of dental intraoral X-ray machines was not significantly increased in ten years. The statistical analysis between the mean focal spot size and nominal focal spot size was significant at the 0.05 level about the more than 3 years used machines.

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A Study on the Improvement of Consumer Dispute in the Apartment House (공동주택 소비자분쟁 경감방안에 관한 연구)

  • Park, Sung-Yong;Kim, Suk-Chul;Oh, Dong-Hyun
    • Journal of Arbitration Studies
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    • v.19 no.3
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    • pp.199-217
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    • 2009
  • During the urbanization progresses, apartments such as the house of commons, representing our homes are situated in space. However, many consumer problems of our country's apartment house are caused by the government's failure of housing policy and consumer dispute resolution system In this study, apartment house and alleviate consumer disputes relating to in proactive ways to improve the government's housing policy was presented. At the same time, since the revision of Consumer Fundamental Act on collective alternative dispute resolution system has proposed scheme, this occurred after a dispute to resolve the dispute can be more efficient ways.

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A Study on the Ways to expand ADR System As a Method of International Trade Dispute Resolution (무역분쟁(貿易紛爭)의 해결수단(解決手段)으로서 ADR활성화(活性化) 방안(方案)에 관한 연구(硏究))

  • Shin, Koon-Jae
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.20
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    • pp.343-365
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    • 2003
  • Dispute plays a key role in maintaining the desirable performance of trade transaction. In an effort to stay competitive in a global marketplace, the Korean companies need to become more aware of alternatives to costly and time-consuming litigation. Korean companies, therefore, should be more concerned with ADR(Alternative Dispute Resolution) system and should utilize ADR to settle their disputes effectively and efficiently. ADR encompasses all process of dispute resolution as a substitute for the traditional litigation. Generally, three kinds of ADR are available in Korea: Negotiation, mediation, and arbitration. This article investigates reasons why ADR isn't used well in Korea and suggests ways how ADR can work best in international trade disputes. To expand ADR system in international trade disputes, it is very important for both the company and the scholar to recognize the concept and usefulness of ADR system. The Korean Commercial Arbitration Board also must help both Korean companies and scholars recognize the mechanism of dispute resolution and utilize ADR system in international trade disputes.

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