• 제목/요약/키워드: a and b values

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1.5T MR 기기를 이용한 확산강조영상에서 b Value의 증가에 따른 요추압박골절 환자의 신호대 잡음비와 현성 확산 계수의 변화 (SNR and ADC Changes at Increasing b Values among Patients with Lumbar Vertebral Compression Fracture on 1.5T MR Diffusion Weighted Images)

  • 조재환;박철수;이선엽;김보희
    • 한국의학물리학회지:의학물리
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    • 제21권1호
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    • pp.52-59
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    • 2010
  • 요추 압박 골절이 있는 환자를 대상으로 1.5 T MR 기기에서 b value의 변화를 이용한 확산강조영상에서 압박 골절이 있는 요추의 신호대 잡음비와 현성 확산 계수가 어떤 변화를 나타내는지 알아보고자 하였다. 2008년 1월부터 2009년 11월까지 요추 MRI를 촬영한 환자 중에서 만성 골다공증으로 척추 압박 골절을 보였던 환자 30명을 대상으로 1.5T MR scanner를 이용하여 b value를 400, 600, 800, 1000, $1200\;s/mm^2$으로 점차 증가시켜가면서 확산강조영상을 각각 획득하였다. 각각의 b value로 획득한 확산강조영상에서 1~5번의 요추체중 척추 압박 골절이 있는 부위와 골절이 있는 부위의 위, 아래 추간판등 세 부위에서 신호대 잡음비를 측정하였고 각각의 b value로 획득한 ADC map 영상에서는 세 부위의 신호대 잡음비와 현성 확산 계수를 측정 하였다. 정량적 분석방법으로 b value $400\;s/mm^2$으로 획득한 확산강조영상과 ADC map영상을 기준으로 각각의 b value로 획득한 영상과 비교하였다. 정성적인 분석방법은 b value $400\;s/mm^2$ 확산강조영상과 ADC map영상의 1~5번의 요추체중 척추 압박 골절이 있는 부위의의 신호강도를 분석하여 이를 기준으로 각각의 b value를 증가시켰을 때의 확산강조영상과 ADC map영상에서 신호강도가 상대적으로 어떻게 변화하는지 알아보았다. 영상의 정량적 분석에서는 확산강조영상에서 b value가 증가함에 따라 척추 압박 골절이 있는 부위와 골절이 있는 부위의 위, 아래 추간판등 세 부위 모두 신호대 잡음비가 상대적으로 감소했다. ADC map영상에서는 b value가 증가함에 따라 척추 압박 골절이 있는 부위와 골절이 있는 부위의 위, 아래 추간판등 세 부위 모두 신호대 잡음비가 상대적으로 감소했다. ADC map영상에서 b value에 따른 관심영역의 현성 확산 계수는 b value가 증가함에 따라 척추 압박 골절이 있는 부위와 골절이 있는 부위의 위, 아래 추간판등 세 부위 모두 현성 확산 계수가 상대적으로 감소했다. 영상의 정성적 분석에서 b value를 $400\;s/mm^2$ 이상으로 증가시킴에 따라 척추 압박 골절이 있는 부위와 골절이 있는 부위의 위, 아래 추간판등 세 부위 모두 신호강도가 점차 감소하였고 b value를 $1,000\;s/mm^2$ 이상으로 했을 때에는 세 부위 모두 영상의 잡음이 매우 심했다. 또한 척추 압박 골절이 있는 부위는 상대적으로 위, 아래 추간판 보다 높은 신호강도를 보였다. 확산강조영상에서 b value를 증가시킴에 따라 척추 압박 골절이 있는 부위와 골절이 있는 부위의 위, 아래 추간판 등 세부위 모두 신호대 잡음비와 현성확산계수가 점차 감소하는 결과를 얻었고 향후 확산강조영상 검사 시 Multi b value를 사용하여 신호의 변화를 인지함으로서 여러 가지 척추질환으로의 적용에 도움을 줄 것이라 사료된다.

동요치 고정에 사용되는 복합레진의 색품질 평가 (Color quality evaluation of composite resins used for splinting teeth)

  • 정지혜;천경준;오용희;장훈상
    • 품질경영학회지
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    • 제45권4호
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    • pp.995-1002
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    • 2017
  • Purpose: The purpose of this study was to evaluate the color stability of composite resins used for splinting teeth by comparing a self-cure resin cement (Superbond C&B, SB), a flowable composite resin (G-aenial Universal Flo A2, GU), and a composite resin exclusively used for splinting teeth (G-Fix, GF) before and after aging in NaOCl. Methods: Resin samples were fabricated to a size of 2 mm thickness and 8.5 mm diameter and light-cured with an LED light curing unit (G-Light, n = 12). Immediately after fabrication, CIE L*a*b* values of the resin samples were measured with a spectrophotometer (CM-5) as baseline. Then, the resin samples were immersed in 5% NaOCl at $60^{\circ}C$ and the color was measured after 23 hours every day for 4 days. Data were analyzed with one-way ANOVA followed by Duncan post hoc test (p<0.05), and color differences (${\Delta}E$) of resin samples before and after NaOCl aging were also calculated. Results: For SB, there were no changes in L* and a* values but changes were observed in b* values. For GU, there were no changes in L* and b* values but in a* values. For GF, changes were observed in L*, a*, and b* values. All resin samples showed highest ${\Delta}E$ between baseline and the 1st day of NaOCl immersion. ${\Delta}E$ of SB, GU, and GF was 4.6 - 5.8, 4.9 - 7.9, and 9.9 - 16.9, respectively. GF showed highest color change during NaOCl aging. Conclusion: The results of this color quality evaluation showed that the composite resin exclusively used for splinting teeth might be more vulnerable to color change during intraoral service.

한국어의 세대별 음향 연구 -단순모음을 중심으로- (A Study on vowel length of Korean monophthong)

  • 이재강
    • 한국음향학회:학술대회논문집
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    • 한국음향학회 2000년도 하계학술발표대회 논문집 제19권 1호
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    • pp.325-328
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    • 2000
  • According to H.B.Lee(1993), standard Korean vowel qualities are as follows: in /i/, /e/, $/\epsilon/$, /a/, /o/, /w/, they have 4 qualities each other and in /er/ there are 3 qualities. The environments of 4 qualities are iong and stressed vowel in word initial, short and stressed vowel in word initial, unstressed vowel in word initial, unstressed vowel in word finial. The aim of this study is to seek and compare with H.B.Lee(1993). Conclusively I could not find on the whole any pattern of the same types of H.B.Lee(1993) in this study And especially in Fl vowel formant values of /er/and /w/, I never found any pattern of the same types of H.B.Lee(1993). Also F2 vowel formant values of $/\varepsilon/$ and /w/ do not have any kind of pattern of the same types of H.B.Lee(1993), between them, the patternize of F2 vowel formant values in /w / is especially difficult. It is the same story of Jaekang Lee(1998). But in some case, the patternize could be done. among the whole vowels, analysis environment b has the wide width on the change of the formant value. As the another result of the analysis It is to possible to make the pattern of the old male group. The old male group on the whole is analyzed to have the most low formant values and the old women group is analyzed to have the most high formants values, but in the most high formant valus there are young women group. And the formant values's rising in 2 cases of the formant value of /er/ is analyzed to have the same pattern of H.B.Lee(1993).

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한국인의 영어 폐쇄음 발화의 정확성과 발음 숙련도와의 관계에 관한 연구 (A Study on the Relation Between Korean Speakers' English Stop Pronunciation Accuracy and Pronunciation Proficiency)

  • 김지은
    • 말소리와 음성과학
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    • 제4권3호
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    • pp.51-58
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    • 2012
  • The purpose of this study is to measure the impact of Korean speakers' English stop pronunciation on their general pronunciation proficiency. For these purposes, 20 Korean speakers read English sentences and their pronunciations were rated by native English speakers. The Korean speakers' VOT values of English stops in sentences were then measured and the relation between the VOT values and native speakers' pronunciation rating was compared. Here, the relation between (1) the proficiency score of each speaker and VOT values; and (2) the proficiency score of each sentence and VOT values were analyzed. The results show that there is a relation between the proficiency score of each sentence and VOT values of /t, b, d, g/; and there is a relation between VOT values of /t, b, d, g/ and proficiency scores of each speaker while these is a weak relation between VOT values of /p, k/ and proficiency scores of each speaker.

물질적 가치 수준에 따른 의복의미와 의복가치관의 비교 (Clothing Meanings and Clothing Values By Material Value levels)

  • 이경아;유태순
    • 한국의류학회지
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    • 제21권3호
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    • pp.524-535
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    • 1997
  • The purpose of this study was to find out the clothing values and meanings by material values. The researcher used the scales of Richins & Dawson (1992) for Materialism Scale. The scales of Prentice (1987) and Ricllins (1994a, 1994b) for privateand public meanings of clothing. The scales of Prentice (1987) and Richins (1994a, 1994b) for importance clothes of private and public meanings.. The scales of Creekmore (1968) for clothing values. The subjects of this study were 154 girl students in the university. The research materials was analyzed by Frequency, MANOVA and Scheffe test The results of this study were as follows; 1) Higher group of material values had an orientation that emphasizes enjoyment values of clothing in private moaning and seems expensive of clothing in public meaning. 2) All group set a high value on both suits and jeans in clothing of private meanie that meant both interpersonal and enjoyment values and put much worth on both suits and mustang that concerned both costly and brand. 3) Higher group had significantly difference in aesthetic value and political value, and lower had significantly differene ineconomic value and theoretical value.

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Palfique Estelite의 경화전후 색조 변화에 관하여 (COLOR CHANGES OF PALFIQUE ESTELITE BETWEEN PRE AND POST IRRADIATIONS)

  • 유타가 요시마;하루히또 다까기;노리꼬 사이렌지;하루히또 이께다;다가시 구로다;히데오 오노세
    • 대한심미치과학회지
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    • 제6권1호
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    • pp.10-17
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    • 1997
  • It is pointed out that the color of composite resin is changing according to it's ploymerization and this color change is a harmful effect for the clinical satisfacion of composite resin restoration. The purpose of this study was to compare the changes of color of newly developed composite resins between before and after exposure of activating light. Five Compostie resins (8 shades) were employed: Palfique Estelite(UL, U, DY, G ; Tokuyama), Photo Clearfil A (US : Kuraray), Photo Clearfil Bright (US ; Kuraray), GC Graft LC(A3 ; GC), Silux Plus(U; 3M), Tristirnulus values of each material were determined before and after curing-light exposure by using a Micro Multi Photometer (MMP-1001, Nihon Denshoku Kogyo). The values were transformed into $L^*\;a^*\;b^*$ system and color changes of the resins were evaluated by the changes of $L^*$, $a^*$ and $b^*$ values for the individual shades. In addition, the effects of resin thickness and background color on color changes were also studied The finding were as follows: 1. Color changes of $L^*$, $a^*$ and $b^*$ values were recognized due to the light exposure for all products. The $b^*$ values of Palfique Estelite showed negligible changes for all shades. 2. The $b^*$ values were affected strongly by the background color, especially when decreasing the brightness on the background color.(Request original article reprints to Dr. Aoshima)

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탈색조건이 모발의 성질에 미치는 영향 (Effects of Bleaching Conditions on the Properties of Hair)

  • 신승엽;정혜원;황나원;황희종
    • 한국의류학회지
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    • 제36권8호
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    • pp.875-884
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    • 2012
  • Many Koreans have recently bleached their black hair to blond or a light color due to the influence of their favorite Korean idols. Bleaching effects were studied under various bleaching conditions, such as the concentration of oxidants, the ratio between bleach accelerant and oxidant, and treatment temperature and time. The degree of damage of bleached hair with the same color difference (${\Delta}E$) intervals was observed in SEM images, the retention of breaking load and the change of color after dyeing. The ratio between bleach accelerant and oxidant of 1:2.5 was an effective condition. $L^*$ values of the bleached hair treated with 9% oxidant increased to 90 min. At a treatment temperature of $30^{\circ}C$, $a^*$ values were maximum at 30 min and then decreased as time further increased; however, $b^*$ values of the bleached hair increased as the treatment time increased. At $45^{\circ}C$, both of $a^*$ and $b^*$ values showed a maximum at a specific time. Bleaching efficiency was influenced most by temperature, followed in order by time, and oxidant concentration. As the treatment time increased, $L^*$ values greatly increased with twice treatment; however, $a^*$ and $b^*$ values decreased. Bleached hair, which had a color difference of higher than 30, showed the scales were completely removed and the retention of the breaking load greatly decreased. Highly bleached hair showed a great decrease in $L^*$ values by dyeing; however, dyeing with bright colors was more indicative to the effect of bleaching.

디지털 색채 분석을 이용한 민어(Miichthys miiuy) 생식소의 성숙도 판정 (Determining of Maturity Gonads for Brown Croaker Miichthys miiuy Using Digital Color Analysis)

  • 정재묵;김영혜;문경진;최석진
    • 한국수산과학회지
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    • 제57권3호
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    • pp.253-261
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    • 2024
  • This study investigated the digital color profiles corresponding to different maturity stages and levels of brown croaker Miichthys miiuy specimens collected from the Southern Sea of South Korea. Maturity stages were determined using photomicrographs of ovarian developmental phases, which were compared with digital color values. Brown croaker specimens ranged from 24 to 81 cm in standard length; mature ovaries were predominantly observed in specimens that exceed 40 cm in length. Monthly ovary color values were primarily concentrated in the 1st and 4th quadrants, with both a* and b* values falling within a range of ±15 centered on the origin. Similarly, the testes color values were predominantly situated in the 4th quadrant, with a* and b* values ranging from -5 to 15 and 10 to 14, respectively. While the color values of the mature and spawning stages overlapped within a narrow range, distinguishing between them required both the color value and monthly color value distribution to be considered. Thus, this study underscores the efficacy of digital color measurements for assessing brown croaker gonad maturity, and provides more quantitative insights compared to subjective visual assessments by humans.

가축분뇨수의 색소오염물질 분해과정 측정 영상처리 시스템 (Image Processing System for Measuring the Chromatophore Pollution Solution of and Animal Slurry Using Optical-Density)

  • 이대원;김현태;김용석;민병로;이강춘;박은석;한정환;이수희;김정동
    • 한국축산시설환경학회지
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    • 제7권2호
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    • pp.103-110
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    • 2001
  • This study conducted to monitor decomposition process of the charomatophore pollution solution of an animal slurry by using a CCD camera. After the solution was put into test tube, the images(R, G, B, H, L, S) values of the solution were measured by the imgae processing system, and those of it\`s optical density were measured for three hours to be decomposed by microscopic organism. The values of measured for three hours to be decomposed by microscopic organism. The values of measured images(R, G, B, H, L, S) were analysed and compared with those of the optical density. Some of the results are as follows. 1. High correlation coefficients, which analyzed by using data on linear equations, were 0.9557 and 0.9672. They were decreased regularly in this R-value experiment of RGB level. The microscopic organism in this experiment was effective for decomposition of the red charomatophore pollution solution. 2. The values of all correlation coefficients from relationship between RGB-value and optical density were more than 0.95 except H-values. RGB-values, which were average values of summed R, G, B values, had correlation coefficients of 0.9863, 0.9937. These results showed so good relationship that decomposition process of charomatophore pollution solution could be monitored by a image processing system.

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Screening of Protein Tyrosine Phosphatase 1B Inhibitory Activity from Some Vietnamese Medicinal Plants

  • Hoang, Duc Manh;Trung, Trinh Nam;Hien, Phan Thi Thu;Ha, Do Thi;Van Luong, Hoang;Lee, Myoung-Sook;Bae, Ki-Hwan
    • Natural Product Sciences
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    • 제16권4호
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    • pp.239-244
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    • 2010
  • Protein tyrosine phosphatase 1B (PTP1B), a negative regulator of insulin signaling, has served as a potential drug target for the treatment of type 2 diabetes. The MeOH extracts of twenty-nine medicinal plants, traditionally used in Vietnam as anti-diabetes agents, were investigated for PTP1B inhibitory activity in vitro. The results indicated that, most materials showed moderate to strong inhibitory activity with $IC_{50}$ values ranging from $3.4\;{\mu}g/mL$ to $35.1\;{\mu}g/mL$; meanwhile, eleven extracts (37.9%) could demonstrate PTP1B activity with $IC_{50}$ values less than $15.5\;{\mu}g/mL$; sixteen extracts (55.2%) could demonstrate PTP1B activity with $IC_{50}$ values ranging from $15.5\;{\mu}g/mL$ to $35.1\;{\mu}g/mL$. The study may provide a proof, at least in a part, for the ethno-medical use in diabetes disease of these plants.