• Title/Summary/Keyword: ACR

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Comparison of subjective video quality assessment methods for multimedia applications (멀티미디어 응용을 위한 주관적 동영상 품질평가 방법의 비교분석)

  • Choe, Ji-Hwan;Jeong, Tae-Uk;Choi, Hyun-Soo;Lee, Eun-Jae;Lee, Sang-Wook;Lee, Chul-Hee
    • Journal of Broadcast Engineering
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    • v.12 no.2
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    • pp.177-184
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    • 2007
  • In this paper, we compared two subjective assessment methods DSCQS(Double Stimulus Continuous Quality Scale method) and ACR(Absolute Category Rating). These methods are widely used in order to evaluate video quality for multimedia application. We performed subjective quality tests using DSCQS and ACR methods. The subjective scores obtained by the DSCQS and ACR methods show that these methods are highly correlated in terms of MOS(Mean Opinion Score) and have slightly lower correlation in terms of DMOS(Difference Mean Opinion Score). The results indicate that ACR method is an effective subjective quality assessment method, which shows compatible performance with DSCQS method and can evaluate a larger number of video sequences.

Evaluation of the Noise Power Spectrum by Using American College of Radiology Phantom for Magnetic Resonance Imaging (자기공명영상에서 ACR 팬텀을 이용한 잡음전력스펙트럼 평가)

  • Jung-Whan Min;Hoi-Woun Jeong
    • Journal of radiological science and technology
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    • v.47 no.1
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    • pp.21-28
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    • 2024
  • This study was purpose to quantitative evaluation of comparison of the image intensity uniformity and noise power spectrum (NPS) by using American college of radiology (ACR) phantom for magnetic resonance imaging (MRI). The MRI was used achiva 3.0T MRI and discovery MR 750, 3.0T, the head and neck matrix shim SENSE head coil were 32 channels receive MR coil. The MRI was used parameters of image sequence for ACR standard and general hospital. NPS value of the ACR standard T2 vertical image in GE equipment was 7.65E-06 when the frequency was 1.0 mm-1. And the NPS value of the ACR hospital T1 region of interest (ROI) 9 over all vertical image in Philips equipment was 9E-08 when the frequency was 1.0 mm-1 and the NPS value of the hospital T2 ROI 9 over all vertical image in Philips equipment was 1.06E-07 when the frequency was 1.0 mm-1. NPS was used efficiently by using a general hospital vertical sequence more than the standard vertical sequence method by using the ACR phantom. Furthermore NPS was the quantitative quality assurance (QA) assessment method for noise and image intensity uniformity characteristics was applied mutatis mutandis, and the results values of the physical imaging NPS of the 3.0T MRI and ACR phantom were presented.

The Effects of Ethanol Extract from Atractylodes Chinensis Rhizome on the Mast Cell-Mediated Inflammatory Responses (창출(蒼朮) 에탄올 추출물이 비만세포 매개 염증반응에 미치는 영향)

  • Kim, Sun-Min;Kim, Kyung-Jun
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.24 no.1
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    • pp.45-63
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    • 2011
  • Objective : Atractyloides Chinensis Rhizome (ACR) is widely used in oriental medicine as a remedy for an inflammation and an allergic disease. However, as yet there is no clear explanation of how ACR affects the production of inflammatory cytokine. This study was to determine the effects of ACR on the mast cell-mediated inflammatory responses. Method : The amount of inflammatory cytokine production induced by the phorbol myristate acetate (PMA) plus calcium ionophore(A23187) in the human mast cell line (HMC-1) incubated with various concentrations of ACR was measured. The TNF-${\alpha}$ protein levels were analysised by Western blots. The TNF-${\alpha}$, IL-6 and IL-8 secreted protein levels were measured by the ELISA assay. The TNF-${\alpha}$, IL-6 and IL-8 mRNA levels were measured by the RT-PCR analysis. NF-${\kappa}$B, phospho-I${\kappa}$B and MAPKs were examined by Western blot analysis. The NF-${\kappa}$B promoter activity was examined by a luciferase assay. Results : 1. The expressions of TNF-${\alpha}$ and TNF-${\alpha}$ mRNA were decreased dose-dependently at 0.05-0.2mg/$m\ell$ of ACR and significantly decreased at 0.2mg/$m\ell$. 2. The expressions of IL-6 and IL-6 mRNA were decreased dose-dependently at 0.05-0.2mg/$m\ell$ of ACR and significantly decreased at 0.2mg/$m\ell$. 3. The expressions of IL-8 and IL-8 mRNA were decreased dose-dependently at 0.05-0.2mg/$m\ell$ of ACR and significantly decreased at 0.2mg/$m\ell$ specially. 4. The expressions of Phosphorylated-JNK were decreased, not p38, ERK 5. The expressions of NF-${\kappa}$B were decreased dose-dependently at 0.1-0.2mg/$m\ell$ of ACR. The expressions of Phosphorylated I${\kappa}$B were significantly decreased at 0.2mg/$m\ell$. In addition, ACR suppressed PMA plus A23187-induced NF-${\kappa}$B promoting activity. Conclusion : It is suggested that ACR should suppress through inhibition of NF-${\kappa}$B activity and cytokine production.

Analysis of the Dental Implants MRI Artifacts by Using the ACR Phantom (ACR 팬텀을 이용한 치아 임플란트 자기공명영상 인공물 분석)

  • Shin, Woon-Jae
    • Journal of the Korean Society of Radiology
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    • v.10 no.8
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    • pp.629-635
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    • 2016
  • ACR phantom for quality control of magnetic resonance imaging equipment can evaluate magnetic resonance imaging picture quality through various structures within the phantom. In this study, percent Signal Ghosting and Slice position accuracy of imaging could be analyzed by attaching implant and the wire for correction of tooth using ACR phantom in Head coil of 3.0T equipment. In the T1 weighted imaging of the first slice and the eleventh slice of implant, the slice position accuracy appeared to be good in ingress bandwidth 300, and it was good in ingress bandwidth 130 when wire for correction was attached. Percent Signal Ghosting in the seventh slice of SE T1 weighted imaging, implant and wire for correction added all appeared to be good when ingress bandwidth was 230. It is thought that in case of implant dental prosthesis patients in brain exam using magnetic resonance imaging, optimum image can be obtained by changing ingress bandwidth.

Effects of Using Illite Warm Water Mats on Lactate, CRP and ACR Induced High Intensity Exercise in Adults (일라이트 온수매트 사용이 고강도 운동으로 유발된 성인의 젖산, CRP, ACR에 미치는 영향)

  • Choi, Youngjun;Kim, Hyunjun
    • Journal of The Korean Society of Integrative Medicine
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    • v.8 no.4
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    • pp.133-142
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    • 2020
  • Purpose : The purpose of this study was to investigate the effective recovery method of exercise-induced fatigue and muscle pain by comparing the effect of the use of illite hot mat product and general hot mat product on the recovery of muscle pain induced by high intensity exercise. Methods : To measure and analyze the changes in lactic acid, CRP, and ACR according to the high-intensity circuit training program, this study was conducted for the healthy adult men and women, who exercise st the K-region sports center. A total of 45 subjects were studied in 15 groups of 15 patients who received an illite hot-water mat recovery group (A group), 15 general hot-water mat recovery group (B group), and 15 control group (C group). The circuit training exercise program was conducted as a one-time exercise, and each exercise time consisted of 30 minutes of warm-up exercise, 5 minutes of main exercise, 20 minutes of clean-up exercise, and 5 minutes of strength exercise. The intensity setting was high intensity of subjective exercise intensity It carried out by setting to (14-16RPE). Results : Changes in Lactic Acid Concentration There was a significant difference in the lactic acid concentrations between the groups after the high intensity circuit training program (p <.05). The illite rest group (A) decreased 7.71 mmol / L and the control group decreased 4.03 mmol / L. Significantly decreased (p <.05). Changes in ACR Concentration. There was a significant difference in the ACR concentrations Significant differences were found in CRP and ACR during the recovery period after exercise. (p <.05), the elite rest group (A) decreased 2.47 mg / mmol, and the control group increased 1.63 mg / mmol. There was a significant difference (p <.05). Conclusion: The static rest on a heated mat after high-intensity exercise has an effect on changes in blood lactate and ACR levels.

Evaluation of Image Quality according to Insert Position and Thickness Change by Fabricating Modified ACR Phantom in Mammography (유방엑스선검사에서의 변형된 ACR 팬텀 제작을 통한 모조병소의 위치와 두께 변화에 따른 영상의 품질 평가)

  • Uhm, Hyon-Ja;Park, Chanrok
    • Journal of radiological science and technology
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    • v.45 no.2
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    • pp.103-109
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    • 2022
  • To maintain improved image quality in mammography, the quality control process is performed using the ACR (American college of radiology) phantom. In addition, many studied were performed by fabricating the customized breast phantom to provide more information in mammography. Thus, the purpose of this study was to evaluate the image quality by designing the modified ACR phantoms. The five modified acrlylic ACR phantoms were designed by considering insert position and phantom thickness. The phantoms were consisted of 4.5, 3.0, and 1.5 cm in terms of phantom thickness, and 3.0, 2.0, and 0.5 cm in terms of insert position, respectively. The acquired images were evaluated by PSNR (peak signal to noise ratio), RMSE (root mean square error), CC (correlation coefficient), CNR (contrast to noise ratio), and COV (coefficient of variation). Based on the similarity analysis, the result is suitable between conventional and new designed phantoms. In addition, the CNR and COV results in terms of insert position showed that image quality for 0.5 cm was 2.3 and 27.4% improved compared with 2 and 3 cm, respectively. According to phantom thickness results, the CNR result for 1.5 cm and COV result for 4.5 cm were 50.1 and 62.7% improved compared with that those conditions. In conclusion, we confirmed that the image quality depends on the breast size and thickness through modified ACR phantom study.

Optical Design of Reflector of Automotive Headlamp (자동차 헤드램프 반사경의 광학 설계)

  • 사종엽;박정공
    • Transactions of the Korean Society of Automotive Engineers
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    • v.12 no.2
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    • pp.190-196
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    • 2004
  • ACR(All Clear Reflector), also widely referred to as FFR(Free Form Reflector), were designed in general and intelligent ways using a NUDBS surface for the mathematical modelling of the reflector shape and artificial intelligence as the optimum design algorithm. An ACR, which consists of a continuous surface reflector and clear outer lens, offers styling advantages and provides a high quality light performance. The clear outer lens of an ACR remains efficient even with a highly inclined shape, as in the design of a sports car, as well as the complete clearness of the reflector surface eliminates the nuisance of stray light caused by the steps between adjacent segments of multi-faced reflectors. The application of an ACR to low beam lamp was so sucessful to obtain the sharp cut-off with the lens-free single-surfaced-smooth reflector. The design technique of ACR was tested with all types of lamps, including low beams, high beams, and fog lamps.

AcrAB-TolC, a major efflux pump in Gram negative bacteria: toward understanding its operation mechanism

  • Soojin Jang
    • BMB Reports
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    • v.56 no.6
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    • pp.326-334
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    • 2023
  • Antibiotic resistance (AR) is a silent pandemic that kills millions worldwide. Although the development of new therapeutic agents against antibiotic resistance is in urgent demand, this has presented a great challenge, especially for Gram-negative bacteria that have inherent drug-resistance mediated by impermeable outer membranes and multidrug efflux pumps that actively extrude various drugs from the bacteria. For the last two decades, multidrug efflux pumps, including AcrAB-TolC, the most clinically important efflux pump in Gram-negative bacteria, have drawn great attention as strategic targets for re-sensitizing bacteria to the existing antibiotics. This article aims to provide a concise overview of the AcrAB-TolC operational mechanism, reviewing its architecture and substrate specificity, as well as the recent development of AcrAB-TolC inhibitors.

A Study on Standardization of Performance Evaluation for Autonomous Cleaning Robot (자율청소로봇 성능평가 표준화에 관한 연구)

  • Ryu Jae-Chang;Hong Ju-Pyo;Rhim Sung-Soo;Lee Soon-Geul;Park Kwang-Ho
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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    • pp.1054-1059
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    • 2005
  • To support the expansion of the autonomous robot market, the establishment of evaluation standards of the robot performance are essential. In this paper, to venture the standardization of the performance evaluation of the autonomous robot, the authors take the autonomous cleaning robot(ACR) as the initial stepping stone. Recently, the ACR has been being developed and marketed actively in many countries including Korea and it believes to be the fore-runner among various types of autonomous robot products. Standards of the performance evaluation for the ACR could be easily modified and applied to other autonomous robots. This paper formulates and suggests a group of standards for the performance evaluation based on a evaluation platform for the ACR. The newly developed performance evaluation platform has been designed to include all the important aspects of living environments in reality. In the platform the performance of the ACR is measured in terms of mobility, cleaning performance, avoidance of obstruction(safety), and operation noise. A few commercially available ACR products are collected and tested in the evaluation platform and compared against the performance evaluation standards formulated.

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In vivo Evaluation of Flow Estimation Methods for 3D Color Doppler Imaging

  • Yoo, Yang-Mo
    • Journal of Biomedical Engineering Research
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    • v.31 no.3
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    • pp.177-186
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    • 2010
  • In 3D ultrasound color Doppler imaging (CDI), 8-16 pulse transmissions (ensembles) per each scanline are used for effective clutter rejection and flow estimation, but it yields a low volume acquisition rate. In this paper, we have evaluated three flow estimation methods: autoregression (AR), eigendecomposition (ED), and autocorrelation combined with adaptive clutter rejection (AC-ACR) for a small ensemble size (E=4). The performance of AR, ED and AC-ACR methods was compared using 2D and 3D in vivo data acquired under different clutter conditions (common carotid artery, kidney and liver). To evaluate the effectiveness of three methods, receiver operating characteristic (ROC) curves were generated. For 2D kidney in vivo data, the AC-ACR method outperforms the AR and ED methods in terms of the area under the ROC curve (AUC) (0.852 vs. 0.793 and 0.813, respectively). Similarly, the AC-ACR method shows higher AUC values for 2D liver in vivo data compared to the AR and ED methods (0.855 vs. 0.807 and 0.823, respectively). For the common carotid artery data, the AR provides higher AUC values, but it suffers from biased estimates. For 3D in vivo data acquired from a kidney transplant patient, the AC-ACR with E=4 provides an AUC value of 0.799. These in vivo experiment results indicate that the AC-ACR method can provide more robust flow estimates compared to the AR and ED methods with a small ensemble size.