• 제목/요약/키워드: Evaluation of correlations

검색결과 808건 처리시간 0.021초

Definition and Correlation for Spray Angle in Non-Reacting Diesel Fuel Sprays

  • No, Soo-Young
    • 한국분무공학회지
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    • 제11권4호
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    • pp.244-250
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    • 2006
  • Of the macroscopic spray characteristics of non-reacting diesel fuel sprays, the spray angle reflects directly the atomization and air entrainment processes downstream the nozzle. In addition, spray angle is important because it will be closely related to the spray penetration. The existing definitions for the measurement of spray angle as well as the correlations for the prediction of spray angle are, therefore, summarized and reviewed. The existing definition of spray angle can be classified into four groups: distance based on orifice diameter, distance based on spray tip penetration, definition based on surface wave, and definition based on atomization. It is strongly required to specify the definition and measurement method when the data for spray angle is reported. The existing correlations for spray angle can be classified into two groups: theoretical and empirical correlations. The study on the evaluation of the existing correlations fer spray angle is required.

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전문직 음성사용자의 주관적 음성평가도구간의 비교 (Comparison of Patient's Subjective Rating Scales for Voice Evaluation in Professional Voice Users with Vocal Fold Lesions)

  • 김재옥;최성희;임성은;최재남;최홍식
    • 대한음성학회:학술대회논문집
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    • 대한음성학회 2007년도 한국음성과학회 공동학술대회 발표논문집
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    • pp.292-294
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    • 2007
  • This study was designed to compare the translated patient's subjective rating scales for voice evaluation (Voice Handicap Index; VHI, Voice-Related Quality of Life; V-RQOL, Voice Rating Score; VRS) into Korean, taken from 24 professional voice users diagnosed with organic voice disorders. First, the correlation amongh those scales were observed. Second, the correlation between the patient's subjective rating scales and acoustic measures (Jitter%, Shimmer%, NHR) were examined. Third, those scales were compared by clinician's objective scale (G in GRBAS scale). Results indicated that significant correlations among the patients' subjective rating scales and significant correlations of clinician's rating scale with jitter% and Shimmer%, but not with NHR were observed. In addition, there were significant correlations of G with VHI and VHI-P (one of subscale of VHI). However, none of acoustic measures were correlated with the patient's subjective rating scales.

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Empirical Correlations for Breakup Length of Liquid Jet in Uniform Cross Flow-A Review

  • No, Soo-Young
    • 한국분무공학회지
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    • 제18권1호
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    • pp.35-43
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    • 2013
  • The empirical correlations for the prediction of breakup length of liquid jet in uniform cross flow are reviewed and classified in this study. The breakup length of liquid jets in cross flow was normally discussed in terms of the distances from the nozzle exit to the column breakup location in the x and y directions, called as column fracture distance and column fracture height, respectively. The empirical correlations for the prediction of column fracture distance can be classified as constant form, momentum flux ratio form, Weber number form and other parameter form, respectively. In addition, the empirical correlations for the prediction of column fracture height can be grouped as momentum flux ratio form, Weber number form and other parameter form, respectively. It can be summarized that the breakup length of liquid jet in a cross flow is a basically function of the liquid to air momentum flux ratio. However, Weber number, liquid-to-air viscosity ratio and density ratio, Reynolds number or Ohnesorge number were incorporated in the empirical correlations depending on the investigators. It is clear that there exist the remarkable discrepancies of predicted values by the existing correlations even though many correlations have the same functional form. The possible reasons for discrepancies can be summarized as the different experimental conditions including jet operating condition and nozzle geometry, measurement and image processing techniques introduced in the experiment, difficulties in defining the breakup location etc. The evaluation of the existing empirical correlations for the prediction of breakup length of liquid jet in a uniform cross flow is required.

포도의 관능적 품질과 객관적 품질인자 상호간의 상관성 (Correlation between Sensory Quality and Instrumental Quality Attributes in 'Campbell Early' Grape)

  • 조순덕;장민선;김동만;김건희
    • 원예과학기술지
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    • 제28권4호
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    • pp.691-695
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    • 2010
  • 포도의 저장 중 소비자 관능평가와 실험에 의한 객관적 품질인자간의 상관성을 통하여 포도 생산의 객관적 지표를 제시하고자 하였다. 포도를 3부위로 나누어 동일부위 절반은 관능검사에 사용하고, 나머지는 분석용 시료로 사용하여 품질요소 간 상관분석을 실시하였다. 저장 기간 중 포도의 이 화학적 품질특성 변화를 보면 가용성 고형물함량은 다소 증가하였으며, 저온저장보다 상온저장에서 더 많은 증가를 보였고, pH 및 적정산도는 저장 중 약간 감소하였으나 처리구간 큰 차이를 나타내지는 않았다. 포도의 객관적 품질평가인자 상호간에는 낮은 상관성을 보여 pH-가용성 고형물함량 간에는 정(+)의 상관을, 적정산도-가용성 고형물함량 및 pH- 적정산도 간에는 부(-)의 상관을 보였다. 포도에 대한 관능평가 항목간의 상관성 분석결과, 신맛과 신맛을 포함한 단맛의 상관성이 0.933로 가장 높은 상관관계를 보였으며, 외관과 단맛과의 상관성이 0.619로 가장 낮았다. 전체적 기호도에 가장 높은 상관관계를 보이는 요인은 조직감($r^2$=0.890)으로 조사되었고, 그 다음이 신맛을 포함한 단맛($r^2$=0.860)이었다. 또한, 관능적인 품질평가 인자와 객관적인 품질인자 간의 상관성 분석결과, 전반적으로 매우 낮았으나 그 중 전체적 기호도에 대한 가용성 고형물함량의 상관성이 다소 높게 나타나, 소비자 관능평가 지표로써의 활용이 가능한 것으로 평가되었다.

Correlations between Foot Sensory Impairment, Timed Up and Go Test and Berg Balance Scale, and Mental Activities for Prevention of Falling in Elderly People

  • Lee, Young-Ho;Jang, Seon-Jung;Kang, Gi-Beom;Choi, Ye-Seul;Hwang, Young-In
    • 대한물리의학회지
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    • 제14권4호
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    • pp.9-17
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    • 2019
  • PURPOSE: This research was designed to study the correlations between physical activities such as foot sensory impairment, balance and ambulatory abilities, as well as fall risk factors and mental activities such as cognitive performance and depression in order to provide fundamental data for the prevention of falling in the elderly. METHODS: A total of 36 elderly people over the age of 65 years who voluntarily joined the research were selected as subjects. Sensory perception in both feet was measured by using a monofilament in 10 parts with each part given one point. The points for each foot were integrated to analyze the correlations between physical and mental activities indices, and the results were analyzed by using Pearson's correlation coefficient. RESULTS: The results of this research show that the extent to which senses in feet were impaired was correlated to TUG, a functional activity index involved in tranfers, gait, and turning movements, which was correlated to BBS (balance index) as well as MMSE-K and K-GDS (mental activities index). BBS was interrelated to FES-K (physical activities index) and MMSE-K. The muscular strength of the right ankle dorsiflexor had mutual relations with FES-K. CONCLUSION: The results of this research indicate that TUG is widely correlated to foot sensory impairment as well as general physical and mental activities in elderly people. BBS was also shown to be correlated with TUG, FES-K, and MMSE-K. Thus, it might be necessary that TUG and BBS be included as two items in physical and mental check-ups for the elderly, and further studies on correlations using evaluation items for physical and mental activities should lead to the simplification of the evaluation criteria.

서방성 경구제형의 개발과 평가 및 생체내.외 상관성 연구를 위한 가이드라인 (Guideline for Extended Release Oral Dosage Forms : Development, Evaluation, and Application of In Vitro/In Vivo Correlations)

  • 최선옥;정성희;엄소영;정서정;김주일;김옥희
    • Journal of Pharmaceutical Investigation
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    • 제35권6호
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    • pp.471-481
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    • 2005
  • In Korea, generic drug and bioequivalence test are the hot issues since a new medical system of separation of dispensary from medical practice was started in 2000. The KFDA(Korea FDA) had revised several times ${\ulcorner}Guidance\;for\;bioequivalence\;test{\lrcorner}$. In vitro dissolution test has been extensively used as a quality control tool for solid oral dosage forms. In an effort to minimize unnecessary human testing, in vitro/in vivo correlations (IVIVC) between in vitro dissolution and in vivo bioavailability are increasingly becoming an integral part on extended release drug product development. The recently published US guidance, ${\ulcorner}Extended\;release\;oral\;dosage\;forms\;:\;development,\;evaluation,\;and\;application\;of\;in\;vitro/in\;vivo\;correlations{\lrcorner}$ will be helpful for us to make our own guideline.

다양한 평가기법을 이용한 금강 대권역의 수질 및 목표수질기준 달성도 평가 (Review on Water Quality and Achievement of Water Quality Goal by Various Evaluation Methods in Geum River)

  • 이재운;정혜성;윤정희;천세억
    • 환경영향평가
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    • 제17권6호
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    • pp.373-380
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    • 2008
  • The Ministry of Environment plans to improve quality of water which is achieved over 85% in rivers and 94% in lakes of the whole country as "Good Water" until 2015. Also, the law of evaluation of water quality and water quality goal were made newly. So, the water quality has evaluated by using new law since 2007. This study evaluated whether "Good Water" and" Water Quality Goal" were achieved or not in 22 middle-sized districts and major 10 lakes of Geum river. The achievement rates of rivers decreased and the achievement rates of lakes mostly were the same for 5 years. In 2007, the achievement rates of "Good Water" were 50% in rivers and 50% in lakes. The achievement rate of "Water Quality Goal" were 59.1% in rivers and 20% in lakes. The water quality in 2007 was evaluated worse than last year in case of rivers. The evaluations of Korea-Comprehensive Water Quality Index(K-CWQI) showed that achievement rates of "Water Quality Goal" were 81.8% in rivers and 0% in lakes. The statistical correlation analysis showed that correlations between BOD and COD were meaningful at the downstream, compared to upstream, generally. In case of lakes, correlations between COD and temperature were meaningful. Also, correlations between COD and Chl-a were meaningful. The Trophic State Index ($TSI_{KO}$) showed that the half of lakes are major over eutrophic status in lakes. These analytical methods such as K-CWQI, $TSI_{KO}$, statistical correlation analysis could be additionally helpful for evaluation of water quality and provide basis data for understanding characteristics of watershed in Geum river.

치과에 내원한 젊은 성인의 교정치료의 필요성과 자기 인식간의 관계 (Associations between normative and self-perceived orthodontic treatment needs in young-adult dental patients)

  • Oshagh, Morteza;Salehi, Parisa;Pakshir, Hamidreza;Bazyar, Leyla;Rakhshan, Vahid
    • 대한치과교정학회지
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    • 제41권6호
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    • pp.440-446
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    • 2011
  • Objective: Our aim was to determine the correlation between dental treatment need as assessed by the components of the index of orthodontic treatment need (IOTN) and a self-evaluation questionnaire in a population selected from the dental clinics of Shiraz, Iran. Methods: The dental treatment needs of 240 participants (120 men and 120 women) were measured on the basis of the IOTN dental health component (IOTN-DHC), IOTN aesthetic component (IOTN-AC), IOTN AC determined by the examiner (IOTN-ACE), and a self-evaluation questionnaire (SEQ). The correlations between the treatment needs assessed by all the methods as well as the correlations of the treatment needs with age and gender were assessed using a Spearman's correlation coefficient (${\alpha}$ = 0.01). Results: All methods were significantly correlated ($p{\leq}0.001$). The associations of IOTN-ACE with IOTN-DHC and SEQ were moderately significant (rho = 0.49 and 0.41, respectively). The associations of IOTN-AC with IOTN-DHC and SEQ were weakly significant (rho = 0.24 and 0.35, respectively). The IOTN-DHC was moderately associated with SEQ (rho = 0.53). Gender and age were not associated with treatment needs estimated by any of the methods used ($p$ > 0.06). Conclusions: The correlations between the self-evaluation and the IOTN components in young adults were close to those reported in children, and IOTN-ACE was more reliable than IOTN-AC.