• Title/Summary/Keyword: T2 Measurement

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Measurement of Apparent Diffusion Coefficient Values from Diffusion-Weighted MRI: A Comparison of Manual and Semiautomatic Segmentation Methods

  • Kim, Seong Ho;Choi, Seung Hong;Yoon, Tae Jin;Kim, Tae Min;Lee, Se-Hoon;Park, Chul-Kee;Kim, Ji-Hoon;Sohn, Chul-Ho;Park, Sung-Hye;Kim, Il Han
    • Investigative Magnetic Resonance Imaging
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    • v.19 no.2
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    • pp.88-98
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    • 2015
  • Purpose: To compare the interobserver and intraobserver reliability of mean apparent diffusion coefficient (ADC) values using contrast-enhanced (CE) T1 weighted image (WI) and T2WI as structural images between manual and semiautomatic segmentation methods. Materials and Methods: Between January 2011 and May 2013, 28 patients who underwent brain MR with diffusion weighted image (DWI) and were pathologically confirmed as having glioblastoma participated in our study. The ADC values were measured twice in manual and semiautomatic segmentation methods using CE-T1WI and T2WI as structural images to obtain interobserver and intraobserver reliability. Moreover, intraobserver reliabilities of the different segmentation methods were assessed after subgrouping of the patients based on the MR findings. Results: Interobserver and intraobserver reliabilities were high in both manual and semiautomatic segmentation methods on CE-T1WI-based evaluation, while interobserver reliability on T2WI-based evaluation was not high enough to be used in a clinical context. The intraobserver reliability was particularly lower with the T2WI-based semiautomatic segmentation method in the subgroups with involved $lobes{\leq}2$, with partially demarcated tumor borders, poorly demarcated inner margins of the necrotic portion, and with perilesional edema. Conclusion: Both the manual and semiautomatic segmentation methods on CE-T1WI-based evaluation were clinically acceptable in the measurement of mean ADC values with high interobserver and intraobserver reliabilities.

Comparison of Size between direct-measurement and 3D body scanning (중국 성인여성의 직접계측과 3D Body scanning 치수 비교 연구)

  • Cha, Su-Joung
    • Journal of Fashion Business
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    • v.16 no.1
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    • pp.150-159
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    • 2012
  • This study intend to analyze differences between 3D body scanning sizes and direct measurement sizes of same subjects. The subjects of study are female students of university in China. 3D data analyze as a 3D Body Measurement Soft System. The conclusion found is as below: In case of circumferences, error between direct-measurement size and 3D body scanning size is from 4.9mm to 62.2mm. The neck circumference size of directmeasurement is bigger than 3D body scanning size. The height error range is from 0.6mm to 51mm. Height of underbust, waist and hip are that direct-measurement sizes are higher than 3D body scanning sizes. Gap of width is from 3.8mm to 21.9mm. The gap range is too narrow relatively to others. Only direct-measurement size of neck width is wider than 3D body scanning size. Error range of length is from 0.3mm to 41.8mm. 3D body scanning sizes of lateral neck to waistline, upperarm length, arm length, neck shoulder point to breast point, shoulder center point to breast point, lateral shoulder to breast point are longer than direct-measurement sizes. They have a negative margin of error. I intend to set up same measurement point between direct-measurement and 3D body scanning but they have some errors because direct-measurement point is applied by a person. 3D body scanning measurement point is settled by automatic system. A measurement point of direct-measurement and 3D body scanning isn't unite. So we need to make a standard of setting up measurement points.

A comparative study on the change of postoperative facial hard tissue profile after maxillary rotational surgery (하악전돌증 환자의 양악 수술 시 상악골 후상방 회전이동 여부에 따른 안면부 경조직 변화량에 대한 비교 연구)

  • Kim, Uk-Kyu;Lee, Sung-Tak;Kim, Tae-Hoon;Song, Jae-Min;Hwang, Dae-Seok;Chung, In-Kyo
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.37 no.4
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    • pp.264-271
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    • 2011
  • Purpose: This study evaluated retrospectively the postsurgical facial hard tissue profile of a Le Fort I osteotomy with/without posterior impaction and rigid internal fixation to correct mandibular prognathism. After observing a difference between the two groups, this measurement was used to prepare a treatment plan for 2-jaw surgery. Patients and Methods: Thirty patients who had undergone orthognathic surgery in Pusan National University Dental Hospital were enrolled in this study. Fifteen patients were treated using a Le Fort I osteotomy with posterior impaction and mandibular setback bilateral sagittal split ramus osteotomy, and the other fifteen patients were treated without posterior impaction. The preoperative (T0), immediate postoperative (T1) and six-month follow-up period (T2) cephalograms were taken and difference between T1-T0 and T2-T2 was analyzed. Results: Both groups was FH-ABp, SNB and ANB showed significant changes in the measurement, whereas only the posterior impaction group showed a change in the SN-U1, occlusal plane, posterior facial height, surgical movement difference from the L1 and B-point. There was no significant statistical change between the immediate postoperative (T1) and six-month follow-up (T2) hard tissue analysis in the two groups. Conclusion: A Le Fort I osteotomy with posterior impaction is considerable for patients with a flat occlusal plane angle, large posterior facial height, prominent B-point, pogonion and labioversed incisal inclination if the indications are well chosen.

The Impact of If Project Types and Ownerships on IT Value Evaluation (IT 프로젝트 유형과 오너쉽이 IT 가치평가에 미치는 영향)

  • 이국희;구본재
    • Journal of Information Technology Applications and Management
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    • v.9 no.3
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    • pp.79-95
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    • 2002
  • As the budget size and complexity of 1T investment are growing, IT value measurement becomes more critical to the success of IT management In public organizations and private firms. It has been known that there are many factors such as IT costs, risks, qualify, and usage that should be taken Into consideration during the process of measuring IT value and making IT Investment decisions. However, little research has been done so far In order to analysis factors affecting the IT value and effectiveness. The purpose of this study Is to Investigate the impact of IT Project types and ownerships on IT value evaluation. The three research questions are as follows : (1) Does IT project type such as transactional, Informational, and infrastructure have any impact on 1T value measurement\ulcorner (2) Does the IT development ownership has any Impact on IT value\ulcorner (3) Does the IT operation ownership has any impact\ulcorner The empirical research was done at S-Electronics, world-wide known and the biggest manufacturing company in Korea, based on the method of structured interview. About 200 individual Information systems have been evaluated to calculate ROI measures, the dependent variable In this study. The results of statistical analysis show that two of three Independent variables, IT project types and IT development ownership, have statistically significant effects on IT value in terms of ROI measures.

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Construction of a Direct Current Magnetometer (직류 자력계의 제작)

  • Chang, Choong-Geun
    • Journal of Sensor Science and Technology
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    • v.5 no.4
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    • pp.9-15
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    • 1996
  • In order to display magnetic signals obtained from a magneto-resistance sensor, a direct current magnetometer was designed and its circuit was constructed. The magnetic fields measured by the home-made magnetometer, which showed good functions of automatic ranging, analog output, and vector sensing, were well agreed with those by commercial MAG-01 magnetometer. The measurement range of the magnetometer was $1\;{\mu}T$ to 1.999 mT, the resolution was -132 dB within 1 Hz bandwidth and the measured magnetic fields could be displayed with $3{\cdot}1/2$-digit LED.

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Precise Measurement of Magnetic Field Using CW-NMR Technique (CW-NMR 기법을 이용한 자기장 정밀측정)

  • 이정한;이대행;김민철;이순칠;홍계원;이호준
    • Journal of the Korean Magnetics Society
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    • v.5 no.1
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    • pp.79-85
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    • 1995
  • A precise magnetic field probe was designed to measure the field distribution inside a superconducting magnet. The operation principle of the developed equipment is based on cw-NMR. The range of field is from 2.8 T to 5.8 T, and the resolution is better than 0.3 ppm NMR samples were water and heavy water contained in a tube of 4 mm diameter and 4mm height. This equipment can be manufactured very inexpensively compared with the currently available commertial ones.

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Design of Downlink Channel for Transportable KOMPSAT Ground Station Using Sub-Carrier Signal (부 반송파를 사용하는 이동형 다목적실용위성 관제국에 대한 하향 링크 채널 설계)

  • Ahn, Sang-Il;Park, Dong-Chul
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.20 no.3
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    • pp.313-321
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    • 2009
  • This paper describes the downlink design of a transportable small-sized KOMPSAT ground station using sub-carrier signal. Based on the analysis of the transmission modes of satellite real-time telemetry and range measurement signals, the downlink channel design of KOMPSAT ground station using sub-carrier signal was processed. By considering the threshold signal-to-noise ratio of real-time 2 kbps telemetry signal and the required signal-to-noise ratio for satellite range measurement, the small-sized KOMPSAT downlink channel with G/T value of 6.5 dB/K was designed. The real G/T of implemented ground station was proven to be 6.62 dB/K when measured using the Sun. Moreover, through interface test with KOMPSAT, the ground station has shown the required link performance for real-time telemetry acquisition using sub-carrier and was consequently evaluated to be adequate for a transportable small-sized KOMPSAT ground station.

UHD 4K end to end broadcast solution over DVB-T2 SFN network using HEVC real time encoding

  • Dimitrakopulos, Nik
    • Broadcasting and Media Magazine
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    • v.19 no.2
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    • pp.36-45
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    • 2014
  • With major sports events such as FIFA World Cup and The Olympic Games coming up, UHDTV technology has been given a major push by broadcasters, test and measurement (T&M), and consumer electronics (TV and set-top box) manufacturers. The increase in picture resolution ($3840{\times}2160$) for 4K and ($7680{\times}4320$) for 8K compared to current HDTV ($1920{\times}1080$), as well as the need to deliver these services in higher frame rates (50/60 up to 100/120fps) translate to a big challenge in UHDTV content delivery to households over terrestrial transmission due to higher data rates. DVB-T2 has been favored by many countries across the world as it is proven to give the best spectral efficiency for terrestrial broadcasting. On the other hand MPEG-4 appears to be the bottleneck for UHDTV since a much higher data rate is needed to deliver such services. Therefore HEVC becomes mandatory for UHDTV delivery over DVB-T2. In this paper, we will give an overview about a complete end-to-end solution for UHDTV delivery over DVB-T2 based on a realistic SFN scenario in Seoul metropolitan area.

A Study on Runoff Properties of Non-point Pollutant in Nakdong watershed by using SWAT model (SWAT 모형을 이용한 낙동강 하구언의 비점오염물질 유출특성 규명)

  • Lee, Eun-Jeong;Choi, Kyoung-Sik;Kim, Tae-Keun
    • Journal of Korean Society of Water and Wastewater
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    • v.26 no.6
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    • pp.815-823
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    • 2012
  • Non-point source pollutants in down stream of Nakdong river were simulated by SWAT. GIS was utilized to make input data of SWAT such as landuse pattern and soil. Meteorological data of 2007 and 2009 were applied for the calibration and validation of runoff in SWAT. It was difficult to calibrate and validate the runoff and nutrient results since a study area was influenced by the tidal effects. Jindong site was selected to escape from the bias of runoff simulation in the coastal area. $R^2$ values of calibration and validation were 0.8 and 0.79. However, $R^2$ values of water qualities were very low level in comparison to runoff. These resulted from the concentration scale of water qualities such as BOD, T-N and T-P. Additionally, tidal influence could effected on the measurements of nutrients. The simulated annual averages and patterns of BOD, T-N and T-P in SWAT were similar to the measurement data. 80 ~ 96 % of nonpoint source pollutants at Nakbon M site were released from April to August of 2009. The ratio of T-N and T-P from nonpoint source were above 50 % during the rainy season.

A Study of Flexible T-DMB Antenna Using Rectangular Stub and Matching Circuit (매칭 회로와 구형 Stub를 이용한 Flexible T-DMB 안테나 구현에 관한 연구)

  • Kim, Ho-Jin;Lee, Seon-Hyeon;Lee, Young-Hun;Lee, Sang-Seok
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.22 no.2
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    • pp.236-244
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    • 2011
  • In this paper, we proposed flexible T-DMB dipole-shaped antenna that has strength of glass antenna and also has portability and ease of production. The input impedance of antenna according to vehicle body-effect was considered in order to install the antenna on the top of the front window. Installation position of on-glass antennas are changeable defends on driver, so we proposed Interdigital capacitor in feeding point to achieve matching characteristic with no position limit. The measurement result showed good return loss characteristic-below -6 dB in the T-DMB frequency band and maintained fixed resonant frequency.