• 대한방사선기술학회지:방사선기술과학
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• 제40권2호
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• pp.261-267
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• 2017

저 선량 흉부 전산화단층촬영(low dose computed tomography; LDCT)검사 시 기존의 검사방법인 필터보정역투영법인 FBP(filted back projection)와 적응식 통계적 반복 재구성법인 ASIR(adaptive statistical iterative reconstruction)의 적용 및 관전압 변화에 따른 영상의 화질과 피폭선량을 비교 평가해 보고자 하였다. 흉부 phantom을 이용하여 재구성방법에 따라 FBP와 ASIR적용(10%, 20%)을 하였고, 관전압(100kVp, 120kVp)에 변화를 주어 실험을 하였다. 화질평가를 위해 back-ground noise와 signal-noise ratio(SNR), contrast-noise ratio(CNR)를 구하였으며, 선량평가를 위해 CTDIvol과 DLP를 구하였다. 화질평가에 있어 kVp에 따른 ascending aorta(AA) SNR과 inpraspinatus muscle(IM) SNR은 AA SNR과 IM SNR은 유의한 차이가 있었다(p < 0.05). 선량평가에 있어 CTDIvol과 DLP는 유의한 차이가 있었으며(p < 0.05), CTDIvol은 120 kVp, FBP가 2.6 mGy, 120 kVp, 10%-ASIR가 2.38 mGy, 120kVp, 20%-ASIR가 2.17 mGy로 0.43 mGy 감소하였고, 100 kVp, FBP가 1.61 mGy, 100 kVp, 10%-ASIR가 1.48 mGy, 100 kVp, 20%-ASIR가 1.34 mGy로 0.27 mGy 감소하였다. 또한 DLP에서는 120 kVp, FBP가 $103.21mGy{\cdot}cm$, 120 kVp, 10%-ASIR가 $94.57mGy{\cdot}cm$, 120 kVp, 20%-ASIR가 $85.94mGy{\cdot}cm$로 $17.27mGy{\cdot}cm$(16.7%) 감소하였고, 100 kVp, FBP가 $63.87mGy{\cdot}cm$, 100 kVp, 10%-ASIR가 $58.54mGy{\cdot}cm$, 100 kVp, 20%-ASIR가 $53.25mGy{\cdot}cm$로 $10.62mGy{\cdot}cm$(16.7%)로 감소하였다. 재구성방법에 따른 FBP와 ASIR 10%, 20%에서는 화질의 변화 없이 선량을 줄일 수 있어 흉부 low dose CT검사 시 ASIR 20%적용하여 검사하는 것이 좋으며, 관전압 변화에 따른 120 kVp와 100 kVp에서는 선량은 크게 줄어들었지만, noise가 증가하여 화질이 떨어지는 것으로 나타났다.

• 한국균학회지
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• 제24권3호통권78호
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• pp.167-175
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• 1996

Ganoderma lucidum 균주는 인공 배지 상에서 광에 의하여 자실체 원기가 형성되었으며, 광질이 자실체 원기 형성에 미치는 영향을 조사한 결과, 자실체 원기 형성능을 가지고 있는 5균주중 3균주는 공시한 모든 형광등의 아래에서 즉, BLB, 순청색, 순녹색, 순황색, 순적색 형광등의 아래에서 자실체 원기가 형성되었고, 2균주는 BLB 형광등을 제외한 가시광선 영역에서 형성되었다. 그러나 암상태에서는 공시한 모든 균주가 자실체를 형성하지 않았다. 자실체 원기는 광도 0.05에서 $10.0\;{\mu}mol\;m^{-2}s^{-1}$의 범위에서 형성되었고, 광도가 $0.5\;{\mu}mol\;m^{-2}s^{-1}$ 이상에서는 자실체 원기의 수가 감소하였다. 주기적인 광조사가 자실체 원기의 형성에 미치는 영향을 조사한 결과, Gl-009균주는 자실체 원기의 수와 무게가 연속광을 조사한 경우보다 증가하였다. 자실체원기를 형성하기 위해서는 최소 4일간의 광조사가 필요하였다. 단색광의 조사가 자실체 원기의 형성에 미치는 영향을 조사한 결과 Gl-003 균주는 400에서 800 nm의 모든 단색광 처리구에서 자실체 원기가 형성되었고, 그 외의 4균주는 400에서 500 nm, 그리고 700에서 750 nm 범위에서 형성되었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.575-578
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• 1999

The main objective of this study was to examine structural behavior of reinforced concrete column and steel beam joint. composite specimens about 3/4 of the actual beam column connection assembly were tested by applying cyclic load through actuators. Test variables include face bearing plate(FBP), extended face bearing plate(E-FBP), VIR, U-bar and sub beam. There is not much differenced between specimens with sub beam and without sub beam. Test results also show that the joint strength of test specimen is close to the predicted strength by ASCE guideline.

• Asian-Australasian Journal of Animal Sciences
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• 제9권5호
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• pp.533-538
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• 1996

The rate and extent of digestion of dietary carbohydrates has a tremendous impact on ruminal fermentation and the productivity of the animals. The objective of the study was to determine the dry matter (DM) and neutral detergent fiber (NDF) degradabilities and rate and extent of feed byproducts (cotton seed cake, wheat bran), legumes [berseem (Egyptian clover), lucern (Medicago sativa), cowpeas (Vigna sinensis)], grasses [maize (Zea mays), millet (Panicum miliaceum), sorghum (Sorghum vulgare)] and wheat straw in ruminally fistulated male buffalo calves. By using nylon bags, 10 grams sample was exposed to the ruminal fermentation for 0, 1, 2, 4, 6, 10, 16, 24, 36, 48 and 96 hours. Dry matter and NDF degradability was measured at 48 hours. Extent of DM and NDF disappearance was determined at each time point. Rates of disappearance of DM and NDF were determined by regressing the natural logarithm of the percentage of original DM and NDF remaining in the bags between 1 and 96 hours. The dry matter digestibility (DMD) of the feed byproducts (FBP) and legume forages when incubated in the rumen of male buffalo calves were greater (p < 0.05) than grasses. Extent of digestion followed similar pattern as DMD. Rate of DMD was higher in FBP than in legumes and was the lowest in the wheat straw. The NDF degradability (NDFD) of FBP, legumes and grasses did not differ, however, wheat straw had the lowest NDFD from all the feeds tested. The lowest NDFD of wheat straw may have been due to the depressing effect of lignin on fiber digestion. The FBP and legumes had higher (p < 0.05) rates and lower extents of NDF digestion than grasses.

• 한국조리학회지
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• 제23권7호
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• pp.220-233
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• 2017

The purposes of this study were: (1) to examine the quality characteristics of the Sulgidducks added with barley sprouts by blanching (CON), freeze-drying (FBP), hot-air drying(HBP); (2) to examine the quality characteristics of Sulgidduck such as the moisture content, the color value, the textural properties and the sensory evaluation; (3) to find the optimal ratio of barley sprouts, which were made by the three different drying methods. As a result, the Sulgidduks containing barley sprouts by CON showed a lot of significance and high correlation depending on the amounts of the barley sprout(p<0.05). As the amounts of CON, FBP and HBP increased, the L and the a values of Sulgidducks significantly decreased, whereas the b values of them increased. For the textual properties of the Sulgidducks, on the first day, the concentration in CON up to 6% showed no significant differences in the hardness, cohesiveness, springiness, and chewiness. In case of FBP, the increase in the additives caused decrease in the hardness, adhesiveness, springiness, and chewiness of the Sulgidducks on storage 0 day(p<0.05). As the amounts of HBP increased, the hardness, springiness of the Sulgidducks on the first day decreased(p<0.05). Conclusionally, 6% blanched barley sprout added group, 2% FBP and HBP were highly rated in color, flavor, bitterness, chewiness, overall acceptability and all sensory quality characteristics.

• 한국의학물리학회지:의학물리
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• 제32권4호
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• pp.92-98
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• 2021

Purpose: This study automatically discriminates homogeneous and structure edge regions on computed tomography (CT) images, and it evaluates the noise level and edge preservation ratio (EPR) according to the different types of iterative reconstruction (IR). Methods: The dataset consisted of CT scans of 10 patients reconstructed with filtered back projection (FBP), statistical IR (iDose⁴), and iterative model-based reconstruction (IMR). Using the 10th and 85th percentiles of the structure coherence feature, homogeneous and structure edge regions were localized. The noise level was estimated using the averages of the standard deviations for five regions of interests (ROIs), and the EPR was calculated as the ratio of standard deviations between homogeneous and structural edge regions on subtraction CT between the FBP and IR. Results: The noise levels were 20.86±1.77 Hounsfield unit (HU), 13.50±1.14 HU, and 7.70±0.46 HU for FBP, iDose⁴, and IMR, respectively, which indicates that iDose⁴ and IMR could achieve noise reductions of approximately 35.17% and 62.97%, respectively. The EPR had values of 1.14±0.48 and 1.22±0.51 for iDose⁴ and IMR, respectively. Conclusions: The iDose⁴ and IMR algorithms can effectively reduce noise levels while maintaining the anatomical structure. This study suggested automated evaluation measurements of noise levels and EPRs, which are important aspects in CT image quality with patients' cases of FBP, iDose⁴, and IMR. We expect that the inclusion of other important image quality indices with a greater number of patients' cases will enable the establishment of integrated platforms for monitoring both CT image quality and radiation dose.

• Nuclear Engineering and Technology
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• 제53권1호
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• pp.258-265
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• 2021

High levels for noise and a loss of true signal make the quantitative interpretation of nuclear medicine (NM) images difficult. An application of profile optimization using a sigmoidal function in this study was used to acquire the NM images with high quality. And the images were acquired by using three kinds of reconstruction method using each same sinogram: a standard filtered back-projection (FBP), an iterative reconstruction (IR) technique, and the sigmoidal function profile optimization (SFPO). Comparison of image according to reconstruction method was performed to show a superiority of the SFPO for imaging. The images reconstructed by using the SFPO showed an average of 1.49 times and of 1.17 times better in contrast than the results obtained using the standard FBP and the IR technique, respectively. Higher signal to noise ratios were obtained as an average of 12.30 times and of 3.77 times than results obtained using the standard FBP and the IR technique, respectively. This study confirms that reconstruction with SFPO (vs FBP and vs IR) can lead to better lesion detectability and characterization with noise reduction. It can be developed for future reconstruction technique for the NM imaging.

• 한국방사선학회논문지
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• 제17권6호
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• pp.819-825
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• 2023

흉부 CT 검사 조건 중 관전압을 100, 80 kVp, 재구성 알고리즘을 FBP, ASIR-V, DLIR로 변화 적용하여 검사 선량과 화질 변화를 비교 분석해 보았다. 그 결과 기존 관전압 보다 낮은 관전압인 100 kVp 에서 ASIR-V, DLIR 적용 시 선량을 낮추면서 120 kVp, FBP 적용 시와 가장 유사한 화질로 구현. 특히, DLIR 재구성 영상은 모든 관전압에서 SNR, CNR이 우수하였다. 또한, SSIM 지수가 1에 가장 근사하게 분석되어 원본 영상과 가장 유사도가 높은 것을 알 수 있었다. 따라서 반복적으로 흉부 CT 검사를 시행하는 경우 DLIR 적용은 검사 선량을 약 29.7% 감소시킬 수 있어 CT 검사의 가장 큰 문제점인 검사로 인한 피폭을 일부 해결하는 데 도움을 줄 수 있을 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제11권6호
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• pp.934-939
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• 2001

The growth inhibition of Campylobacter jejuni ATCC 33291 in the presence of $1\%$ acetic acid at 4, 25, and $42^{\circ}C$, followed by $25^{\circ}C$ and $4^{\circ}C$, at pH 5.5 and pH 6.5, and by the addition of $1\%$ acetic acid aat 4, 25, and $42^{\circ}C$ were determined to be 22, 8.5, and 1.4 min, respectively, in an FBP-SBB medium. The D values of C. jejuni were increased by the addition of chicken and did not follow the linear relationship observed in the FBP-SBB media without chicken. When using distilled water instead of FBP-SBB in the model system, the death rate of C. jejuni was dramatically accelerated. The injured or low cell numbers that were impossible to enumerate using the plate count method, were detected by a polymerase chain reaction and enrichment culture procedure. These results suggested that acetic acid is reliable and effective as a disinfectant, however, it is necessary to take additional care at refrigeration temperatures due to the potential of injred cells during poultry processing.

• 논리연구
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• 제18권1호
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• pp.39-64
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• 2015

수학적 플라톤주의자가 해결해야 할 가장 큰 문제는 바로 베나세라프가 제기하고 필드가 재정식화한 인식론적 문제라고 할 수 있다. 최근에 밸러궈는 자신의 독특한 형태의 수학적 플라톤주의인 FBP 즉 "혈기 왕성한 플라톤주의"는 이 인식론적 문제를 해결할 수 있다는 논의를 전개했다. 필자는 이 논문에서 그런 논의가 얼마나 성공적인가를 평가하면서 그의 논변이 지닌 문제점들을 살핀다. 우선 필자는 밸러궈 특유의 수학적 플라톤주의가 인식론적 문제를 해결한다는 논변을 형식적 측면에서 비판적으로 분석한다. 그리고 밸러궈의 논변과 전략에 대해 마녀주의의 사례를 통해 보다 본격적 반론을 전개한다. 마지막으로 밸러궈가 유비 논변에 기초해 자기 입장을 옹호하려는 대응을 무력화시키기 위한 논의를 펼친다.