• 제목/요약/키워드: value contrast

검색결과 1,403건 처리시간 0.027초

소아 흉부 CT검사에서 조영제 주입에 관한 프로토콜의 최적화 (Optimization of Protocol for Injection of Iodinated Contrast Medium in Pediatric Thoracic CT Examination)

  • 김영균;김연민
    • 한국방사선학회논문지
    • /
    • 제13권6호
    • /
    • pp.879-887
    • /
    • 2019
  • 본 논문의 목적은 흉부 CT검사를 시행하는 소아환자의 조영제 투여를 최소화하고 조영 증강은 최적화하기 위하여, 몸무게의 변화에 따른 생리학적 주입 프로토콜을 정립하는 것이다. 만 10세 이하의 소아환자 80명을 대상으로 연구하였다. 혈관 조영제 300 mgI/ml를 사용하였으며, A그룹은 몸무게 1.5배의 용량을 주입하였고, B, C, D 그룹은 10%씩 감소하면서 생리식염수 5 ~ 15 ml를 추가 주입하였다. 조영제와 생리식염수의 주입량과 속도 및 지연시간을 몸무게와 연동하여 계산할 수 있는 생리학적 모델의 엑셀시트를 적용하였다. 화질평가는 상대정맥, 상행대동맥, 폐동맥, 우심방, 우심실, 좌심방, 좌심실, 하행대동맥, 쇄골하정맥의 CT number와 SNR을 측정하여 그룹간 비교하였으며, 생리식염수 주입에 따른 인공물 감소효과를 파악하기 위하여 쇄골하정맥과 상대정맥의 CT number를 비교하였다. 또한 조영 증강의 정도와 인공물에 대하여 정성적 평가를 추가로 수행하였다. 조영제 주입 프로토콜에 따른 SNR을 비교 평가한 결과, 상대정맥과 폐동맥, 하행대동맥, 우심실, 좌심실에서 유의한 차이를 보였으며, CT number는 모든 장기에서 유의한 차이를 보였다. 특히 조영제를 10% 감소하고 생리식염수를 추가 주입한 그룹은 조영 증강 정도는 차이가 없었으나, 20% 이상 감소한 그룹은 조영 증강의 정도가 낮게 나타났다. 또한 생리식염수 주입한 그룹은 상대정맥과 쇄골하정맥의 조영 증강이 매우 감소되었고, 조영제에 의한 빔 경화 인공물이 상당히 감쇄되었다. 결론적으로 소아의 흉부 CT 검사에서 생리학적 조영제 주입 프로토콜의 적용은 조영제에 의한 인공물을 감소시키면서, 불필요한 조영제 사용을 예방하고 조영 증강의 효과는 향상시킬 수 있었다.

감국 분말을 첨가한 슈거스냅 쿠키의 이화학적 품질 특성 (Physicochemical Properties of Sugar-snap Cookies Prepared with Chrysanthemum indicum Linne Powder)

  • 배현주;이혜연;백재은
    • 한국식품영양학회지
    • /
    • 제22권4호
    • /
    • pp.570-576
    • /
    • 2009
  • This study investigated the physicochemical characteristics of sugar-snap cookies made with various levels(0, 1.5, 3, 4.5, and 6% w/w) of Chrysanthemum indicum Linne powder. Dough pieces were baked for 11 min at $180^{\circ}C$ in an electrically heated rotary oven. All items were measured after cooling for 1 hour at room temperature. The results were as follows. Dough pH was significantly decreased in the 3%, 4.5% and 6% samples in contrast to the control sample(p<0.001). Furthermore, lightness (L*-value) and spread factor decreased significantly according to increasing Chrysanthemum indicum Linne powder concentration(p<0.001). However, dough density was significantly increased in the 3%, 4.5%, and 6% samples in contrast to the control sample(p<0.001). Likewise, the hardness and redness(a*-value) of the cookies increased significantly with increasing Chrysanthemum indicum Linne powder concentration(p<0.001). However, the moisture content of the dough was not significantly affected by the Chrysanthemum indicum Linne powder concentration. Finally, the powder concentration had positive correlations with dough density(p<0.01) and hardness(p<0.01). However, it had negative correlations with dough pH(p<0.01), lightness(L*-value)(p<0.05), and spread factor(p<0.01). Overall, the results showed that there were significant correlations between Chrysanthemum indicum Linne powder concentration and the physicochemical characteristics of the cookies.

열적외선 기기와 3차원 레이저 스캐너를 이용한 암석 표면의 풍화강도 분석 (Analysis The Intensity of Weathering of The Rock Surface Using 3D Terrestrial Laser Scanner and Thermal Infrared Instrument)

  • 이수곤;조항교;쉬징
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2010년도 춘계 학술발표회
    • /
    • pp.1324-1333
    • /
    • 2010
  • This paper is used in a recent civil engineering field in three-dimensional laser-meter tiles using thermal imaging cameras for the weathered rock slopes precisely measured indirectly, to the degree that began in the will. In the field is difficult to access the degree of weathering of the rock slope to the existing direct way to compensate for the shortcomings of 3D Terrestrial Laser Scanner and weathering characteristics of rocks using thermal imaging cameras to get the information to analyze the degree of rock weathering is. Intensity of 3D TLS and the thermal camera with image analysis to analyze the degree of weathering of bedrock in the field of core drilling targeting indoor laboratory tests were analyzed through the study. Granite, gneiss, sandstone, much of the cancerous samples, each experiment has a 40 per category, each of which 30 were used to analyze the data collected. That degree of rock weathering, the rock, depending on the strength of the Intensity values can change, depending on the level of thermal imaging camera, also weathered the changes in temperature could see. Intensity is the strength of weak rocks, the more value decrease, the temperature of the thermal imaging camera through the swell Intensity and notice that the temperature had an inverse relationship. Intensity value of the low strength of weak rock, but the value came out of the rocks have been proved to be largely dependent on the contrast. The contrast of the surface rocks are weathered dark Intensity values lower temperature to swell the contrary, the degree of weathering can be distinguished.

  • PDF

파랑 중 제주 "테우" 틈에 의한 파 흡수효과 (Efficiency of wave absorption by the porous of "Taewoo" of Jeju in regular seaway)

  • 이창헌;최찬문;안장영;조일형
    • 수산해양기술연구
    • /
    • 제49권2호
    • /
    • pp.144-152
    • /
    • 2013
  • In an effort to find the optimum porous of Taewoo through the mathematical model 2 - dimensional tank water experiment among the approached to a problem related to ocean engineering, this study analyzed the porosity by dividing it into 9 cases. As the wave penetrates through the longitudinal porous of the Taewoo model, it was found that there is a wave energy loss because of the phenomenon of the separation of the porous due to the eddy. Looking into the general tendency based on the wave-height meter (probe) data, it was found that the shorter wavelength and higher frequency area, the more reflection coefficients increased, but in contrast, the longer wavelength and lower frequency area, the transmission coefficients showed the increasing trend and energy dissipation was in a similar way with reflection coefficients. In addition, it was found that the bigger the porosity was, the narrower distribution range of reflection coefficients was, and the more its average value decreased. On the other hand the transmission coefficients in direct opposition to reflection was found to show the wider range and the more gradual increase in the average value as porosity was the bigger around the average value. In contrast, energy dissipation rate was found to increase linearly as porosity increased the more around the porosity of 0.2518 but it decreased gradually around the peak point. Through the above results, it is judged that the porous of optimum in the longitudinal direction of the Taewoo model perforated plate was about 2.6cm because it was found that the porosity which produced the lowest reflection and transmission coefficient and the highest energy dissipation. As a result of comparing this to the case where there was no porosity at all, it showed the function of wave absorbing about 31.60%.

Additional Value of Integrated 18F-FDG PET/MRI for Evaluating Biliary Tract Cancer: Comparison with Contrast-Enhanced CT

  • Jeongin Yoo;Jeong Min Lee;Jeong Hee Yoon;Ijin Joo;Dong Ho Lee
    • Korean Journal of Radiology
    • /
    • 제22권5호
    • /
    • pp.714-724
    • /
    • 2021
  • Objective: To evaluate the value of 18F-fluorodeoxyglucose PET/MRI added to contrast-enhanced CT (CECT) in initial staging, assessment of resectability, and postoperative follow-up of biliary tract cancer. Materials and Methods: This retrospective study included 100 patients (initial workup [n = 65] and postoperative follow-up [n = 35]) who had undergone PET/MRI and CECT for bile duct or gallbladder lesions between January 2013 and March 2020. Two radiologists independently reviewed the CECT imaging set and CECT plus PET/MRI set to determine the likelihood of malignancy, local and overall resectability, and distant metastasis in the initial workup group, and local recurrence and distant metastasis in the follow-up group. Diagnostic performances of the two imaging sets were compared using clinical-surgical-pathologic findings as standards of reference. Results: The diagnostic performance of CECT significantly improved after the addition of PET/MRI for liver metastasis (area under the receiver operating characteristic curve [Az]: 0.77 vs. 0.91 [p = 0.027] for reviewer 1; 0.76 vs. 0.92 [p = 0.021] for reviewer 2), lymph node metastasis (0.73 vs. 0.92 [p = 0.004]; 0.81 vs. 0.92 [p = 0.023]), and overall resectability (0.79 vs. 0.92 [p = 0.007]; 0.82 vs. 0.94 [p = 0.021]) in the initial workup group. In the follow-up group, the diagnostic performance of CECT plus PET/MRI was significantly higher than that of CECT imaging for local recurrence (0.81 vs. 1.00 [p = 0.029]; 0.82 vs. 0.94 [p = 0.045]). Conclusion: PET/MRI may add value to CECT in patients with biliary tract cancer both in the initial workup for staging and determination of overall resectability and in follow-up for local recurrence.

디지털 진단방사선촬영에서 부가여과판 사용에 따른 피폭선량 감소와 화질 개선 (Reduction of Patient Dose Exposure and Improvement of Image Quality by Use of Additional Filtration in Digital Radiology)

  • 문수정;김영근;이성길
    • 대한디지털의료영상학회논문지
    • /
    • 제12권1호
    • /
    • pp.19-25
    • /
    • 2010
  • This study is mainly for the reduction of exposure dose by using a heavy elements filter(Gd) in the digital radiology. They contained heavy elements filter of Gd and X-ray beam hardening filters such as Al and Cu. According to the results of experimental evaluation, X-ray property was not changed with variety of kVp in the case of the Gd filter. The surface dose and absorption dose were increased in order of Cu and Al. The contrast of image showed the higher value in order of Cu, Al and Gd. While the use of Gd has increased the numerical value of the CR image, and grayscale has decreased noise value of the DR image.

  • PDF

Hedonic Shopping Value as a Determinant of Brand Loyalty in Apparel Shopping

  • Chang, Eunyoung
    • The International Journal of Costume Culture
    • /
    • 제4권3호
    • /
    • pp.203-216
    • /
    • 2001
  • Subjects were 405 female college students and 505 was utilized for structural equation modeling. As results, hedonic shopping value had positive effects on impulse purohasing, variety seeking, and purchasing involvement. In contrast, interestingly, impulse purchasing did not show any significant effect on brand loyalty and purchasing involvement had rather a positive effect on brand loyalty. There was a Positive effect of hedonic shopping value on brand loyalty. This result indicates that people who get more involved in and enjoy clothing shopping are likely more brand loyal than others. This seems to come from the intrinsic characteristics of shopping. People who enjoy clothing shopping likely have high level of fashion or style concern, and this might lead higher levels of purchasing involvement and brand loyalty. Due to the symbolic characteristics of clothing, the brand loyalty of clothing seems to be more symbolic and emotive rather than utilitarian and cognitive.

  • PDF

An Adaptive Image Quality Assessment Algorithm

  • Sankar, Ravi;Ivkovic, Goran
    • International journal of advanced smart convergence
    • /
    • 제1권1호
    • /
    • pp.6-13
    • /
    • 2012
  • An improved algorithm for image quality assessment is presented. First a simple model of human visual system, consisting of a nonlinear function and a 2-D filter, processes the input images. This filter has one user-defined parameter, whose value depends on the reference image. This way the algorithm can adapt to different scenarios. In the next step the average value of locally computed correlation coefficients between the two processed images is found. This criterion is closely related to the way in which human observer assesses image quality. Finally, image quality measure is computed as the average value of locally computed correlation coefficients, adjusted by the average correlation coefficient between the reference and error images. By this approach the proposed measure differentiates between the random and signal dependant distortions, which have different effects on human observer. Performance of the proposed quality measure is illustrated by examples involving images with different types of degradation.

즉석 추어탕을 냉동 건조미꾸라지의 저장성 (Storage Stability of Freeze Dried Loach for Instant Choo-o-tang)

  • 류홍수;문숙임;이수정;문갑순
    • 한국식품영양과학회지
    • /
    • 제28권1호
    • /
    • pp.153-160
    • /
    • 1999
  • Storage stability of boiled and freeze dried loach and antioxidative effect of Zanthoxylum schinifolium were studied to confirm the possibility in development of instant choo o tang(Korean traditional loach soup). Packaging and storage temperature did not cause a measurable change in in vitro protein digestibility and trypsin indigestible substrate within 45 days of storage but remarkable quality changes were occurred in all samples stored after 60 days. Vacuum packaging and low temperature storage(4 oC) had some effect in retarding protein quality deterioration due to delaying polyunsaturated fatty acid oxidation. Maximum peroxide value and TBA value were reached in 15 days, and there were a slow(TBA value) and rapid reduction(POV) after peaks were reached. In contrast, increasing brown pigment development and fluorescence intensity continued until 90 days of storage. Treatment of ethanolic extracts from Zanthoxylum schinifolium prior to freeze drying could protect against lipid oxidation of freeze dried loach products.

  • PDF

블록기반 정규화 된 이미지 수 표현자 (Block based Normalized Numeric Image Descriptor)

  • 박유영;조상복;이종화
    • 대한전자공학회논문지SP
    • /
    • 제49권2호
    • /
    • pp.61-68
    • /
    • 2012
  • 본 논문에서는 이미지 밝기와 명암을 명확하고 객관적으로 평가하기 위한 정규화된 수 표현자를 제안한다. 제안하는 수 표현자는 이미지를 구성하는 각각의 픽셀 데이터 값을 확률밀도함수(PDF)의 가중치로 사용하고 이를 정규화하여 객관적으로 표현되도록 정의되었다. 제안된 정규화 된 이미지 수 표현자는 감마보정 처리 시에 객관적인 감마 값 선택 기준을 제시하므로 적응형 감마보정처리가 가능하다.