• 제목/요약/키워드: Evaluation of correlations

검색결과 806건 처리시간 0.029초

Ultrasonic characterization of exhumed cast iron water pipes

  • Groves, Paul;Cascante, Giovanni;Knight, Mark
    • Smart Structures and Systems
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    • 제7권4호
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    • pp.241-262
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    • 2011
  • Cast iron pipe has been used as a water distribution technology in North America since the early nineteenth century. The first cast iron pipes were made of grey cast iron which was succeeded by ductile iron as a pipe material in the 1940s. These different iron alloys have significantly different microstructures which give rise to distinct mechanical properties. Insight into the non-destructive structural condition assessment of aging pipes can be advantageous in developing mitigation strategies for pipe failures. This paper examines the relationship between the small-strain and large-strain properties of exhumed cast iron water pipes. Nondestructive and destructive testing programs were performed on eight pipes varying in age from 40 to 130 years. The experimental program included microstructure evaluation and ultrasonic, tensile, and flexural testing. New applications of frequency domain analysis techniques including Fourier and wavelet transforms of ultrasonic pulse velocity measurements are presented. A low correlation between wave propagation and large-strain measurements was observed. However, the wave velocities were consistently different between ductile and grey cast iron pipes (14% to 18% difference); the ductile iron pipes showed the smaller variation in wave velocities. Thus, the variation of elastic properties for ductile iron was not enough to define a linear correlation because all the measurements were practically concentrated in single cluster of points. The cross-sectional areas of the specimens tested varied as a result of minor manufacturing defects and levels of corrosion. These variations affect the large strain testing results; but, surface defects have limited effect on wave velocities and may also contribute to the low correlations observed. Lamb waves are typically not considered in the evaluation of ultrasonic pulse velocity. However, Lamb waves were found to contribute significantly to the frequency content of the ultrasonic signals possibly resulting in the poor correlations observed. Therefore, correlations between wave velocities and large strain properties obtained using specimens manufactured in the laboratory must be used with caution in the condition assessment of aged water pipes especially for grey cast iron pipes.

Computerized occlusal analysis: correlation with occlusal indexes to assess the outcome of orthodontic treatment or the severity of malocculusion

  • Lee, Sang-Min;Lee, Jin-Woo
    • 대한치과교정학회지
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    • 제46권1호
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    • pp.27-35
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    • 2016
  • Objective: The aims of our study were to verify the validity of the T-Scan III system (Tekscan) as an objective occlusal evaluation tool, and to assess the differences between two occlusal indexes - the peer assessment rating (PAR) index and the American Board of Orthodontics objective grading system (OGS) - by comparing the scores derived from the T-Scan III system with the two occlusal indexes and analyzing the correlations between them. Methods: The final study sample included 48 adult volunteers (39 men and 9 women, mean age $24.14{\pm}3.16years$), after excluding 29 volunteers whose occlusion could not be evaluated by the T-Scan III system due to severe skeletal or occlusal problems. PAR index and OGS scores were assessed using dental study models, and measurements of centric occlusion, protrusive movement, and lateral excursion movement were obtained via the T-Scan III system. The results were analyzed to determine correlations. Results: Occlusal analysis by the T-Scan III system was clinically reliable (p < 0.05), and the PAR index and OGS scores were significantly correlated with several measurements obtained with the T-Scan III system (p < 0.05). Conclusions: The T-Scan III system is a quantitative and reliable method for occlusal evaluation, and represents a potential substitute for occlusal indexes. Compared to the PAR index, the OGS scores of more variables were significantly correlated with the T-Scan measurements.

밀싹분말을 첨가한 식빵의 최적화 연구 (A Study of the Optimization of White Pan Bread added with Wheat Sprout Powder)

  • 주신윤;박종대;최윤상;성정민
    • 한국조리학회지
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    • 제24권3호
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    • pp.1-14
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    • 2018
  • The purpose of this study was to determine the optimization mixing ratio of wheat sprout powder (WSP) and hemicellulase for the preparation of white pan bread. Using a response surface methodology, independent variables were WSP and hemicellulase. Dependent variables were physicochemical properties, antioxidant properties and sensory evaluation. Water binding capacity of dough increased with increasing WSP. Color value showed positive correlations with WSP. L value decreased and a, b values increased as WSP increased. The adjusted determination coefficient of texture analysis was calculated to be 0.7230~0.9446 having the p-value less than 0.1. Specific volume of bread showed a positive correlation with hemicellulase and a negative correlation with WSP. DPPH radical scavenging activity and total polyphenol were represented by a linear model and showed positive correlations with WSP. Sensory evaluation were represented by a quadratic model. In conclusion, the optimal formulation for WSP added bread, as assessed by numerical and graphical optimization methods, was WSP 2.36%, hemicellulase 0.069% per wheat flour 100 g. The above results indicate that WSP can be used as health-oriented material in the bread industry. This is also expected to meet demands of consumers who are in the pursuit of healthy food.

Performance Evaluation of Jersey Cattle at Islamabad

  • Khan, R.N.
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권5호
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    • pp.695-698
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    • 2002
  • Performance data (from 1985 to 2000) of Jersey cattle imported from USA and maintained at Islamabad, Pakistan were evaluated. The purpose of this study was to assess the genetic merit of Jersey breed under Pakistani environment for further propagation. Cows with at least two calvings were considered for this study; records on 50 daughter-dam pairs were available on production and reproduction performance traits for genetic evaluation. The average age at first calving in parents was $25.2{\pm}2.4$ m as compared to $23.9{\pm}6.6$ m in progeny. Calving interval in parents and progeny was $416{\pm}74$ and $446{\pm}105$ d; lactation length $301{\pm}51$ and $325{\pm}73$ d; lactation milk yield $2,908{\pm}669$ and $2,707{\pm}903$ lit respectively. All these differences were found to be statistically significant except lactation length. The correlations between age at first calving and total lactation milk was -0.25, between calving interval and total lactation milk yield was 0.14, and between lactation length and total lactation milk yield was 0.79. The $h^2$ of these traits were low indicating important role of environment in expressing the genetic potential of animals. The S.E of $h^2$ of all the traits was high due to large variation in data.

Indirect evaluation of the shear wave velocity of clays via piezocone penetration tests

  • Vinod K., Singh;Sung-Gyo, Chung;Hyeog-Jun, Kweon
    • Geomechanics and Engineering
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    • 제31권6호
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    • pp.623-635
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    • 2022
  • This paper presents the re-evaluation of existing piezocone penetration test (CPTu)-based shear wave velocity (Vs) equations through their application into well-documented data obtained at nine sites in six countries. The re-evaluation indicates that the existing equations are appropriate to use for any specific soil, but not for various types of clays. Existing equations were adjusted to suit all nine clays and show that the correlations between the measured and predicted Vs values tend to improve with an increasing number of parameters in the equations. An adjusted equation, which comprises a CPTu parameter and two soil properties (i.e., effective overburden stress and void ratio) with the best correlation, can be converted into a CPTu-based equation that has two CPTu parameters and depth by considering the effect of soil cementation. Then, the developed equation was verified by application to each of the nine soils and nine other worldwide clays, in which the predicted Vs values are comparable with the measured and the stochastically simulated values. Accordingly, the newly developed CPTu-based equation, which is a time-saving and economical method and can estimate Vs indirectly for any type of naturally deposited clay, is recommended for practical applications.

Genetic Parameters of Milk Yield and Milk Fat Percentage Test Day Records of Iranian Holstein Cows

  • Shadparvar, A.A.;Yazdanshenas, M.S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제18권9호
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    • pp.1231-1236
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    • 2005
  • Genetic parameters for first lactation milk production based on test day (TD) records of 56319 Iranian Holstein cows from 655 herds that first calved between 1991 and 2001 were estimated with restricted maximum likelihood method under an Animal model. Traits analyzed were milk yield and milk fat percentage. Heritability for TD records were highest in second half of the lactation, ranging from 0.11 to 0.19 for milk yield and 0.038 to 0.094 for milk fat percentage respectively. Estimates for lactation records for these traits were 0.24 and 0.26 respectively. Genetic correlations between individual TD records were high for consecutive TD records (>0.9) and decreased as the interval between tests increased. Estimates of genetic correlations of TD yield with corresponding lactation yield were highest (0.78 to 0.86) for mid-lactation (TD3 to TD8). Phenotypic correlations were lower than corresponding genetic correlations, but both followed the same pattern. For milk fat percentage no clear pattern was found. Results of this study suggested that TD yields especially in mid-lactation may be used for genetic evaluation instead of 305-day yield.

Genetic Evaluation of First Lactation Traits in Sahiwal Cattle Using Restricted Maximum Likelihood Technique

  • Choudhary, V.;Kothekar, M.D.;Raheja, K.L.;Kasturiwale, N.N.;Khire, D.W.;Kumar, P.
    • Asian-Australasian Journal of Animal Sciences
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    • 제16권5호
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    • pp.639-643
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    • 2003
  • The data on 283 Sahiwal cows, sired by 16 bulls, maintained at Cattle Breeding Farm of Nagpur Veterinary College and Dairy Farm of Agricultural College, Nagpur, were considered for the estimation of genetic parameters. Variance and covariance estimates of first lactation traits were obtained using restricted maximum likelihood technique (REML). When first lactation milk yield (FLMY), first lactation length (FLL) and average daily yield (ADY) traits were considered for REML analysis, the heritabilities were $0.184{\pm}0.146$, $0.132{\pm}0.131$ and $0.141{\pm}0.133$, respectively. While, genetic and phenotypic correlations between them were medium to high except phenotypic correlations between FLL and ADY (-0.025). REML procedure considering FLMY, age at first calving (AFC) and first service period (FSP) combination exhibits heritabilities as $0.274{\pm}0.173$, $0.506{\pm}0.233$ and $0.274{\pm}0.172$, respectively. Genetic correlations were $-0.120{\pm}0.376$, $0.225{\pm}0.423$ and $0.365{\pm}0.331$ between FLMY and AFC, FLMY and FSP, AFC and FSP, respectively. Phenotypic correlations were 0.057, 0.289 and 0.123, respectively. Considering all five traits REML combination heritabilities estimated were $0.238{\pm}0.162$, $0.160{\pm}0.139$, $0.136{\pm}0.132$, $0.409{\pm}0.209$ and $0.259{\pm}0.168$ for FLMY, FLL, ADY, AFC and FSP, respectively. The genetic correlations were positive except FLMY and AFC. The phenotypic correlations were also positive except FLL and ADY, ADY and FSP. Almost all estimates were associated with high standard error.

대학 강의평가 영향력 요인 중 학생 특성의 효과에 대한 사례 연구 (A Case Study on the Effect of Student Characteristics among the Influential Factors in the Teaching Evaluation at Universities)

  • 조수선
    • 공학교육연구
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    • 제19권6호
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    • pp.38-43
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    • 2016
  • This paper deals with the effect of student characteristics from a case study on the different teaching evaluation scores under the same conditions of professor and course characteristics. In particular, focusing the evaluation score gabs caused by different course achievements of two classes, we can analyze the influence of the student characteristics and interpret the meaning. This case study shows that the student characteristics can lead out a distinct difference in the teaching evaluation scores under the most factors related to professors and courses are controlled, In conclusion, this case study could be appropriately used to support the interpretation of the student characteristic hypothesis among several hypotheses about the meaning of correlations between student achievement and teaching evaluation.

HMM 기반의 한국어 합성음에 대한 PESQ 및 MOS 평가의 상관도 분석 (Correlation Analysis of PESQ and MOS Evaluation for HMM-based Synthetic Korean Speech)

  • 임창송;배건성
    • 말소리와 음성과학
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    • 제2권1호
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    • pp.71-75
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    • 2010
  • The PESQ is an objective speech quality evaluation measure that is known to have a high correlation with a subjective speech quality measure such as MOS. To examine whether it could be useful as an objective quality measure of synthetic speech, we carried out both subjective evaluation tests with MOS and DMOS and an objective evaluation test with PESQ for HMM-based Korean synthetic speech signals and analyzed the correlation between them. Experimental results have shown that the PESQ has correlations of 0.87 with MOS and 0.92 with DMOS. It means that the PESQ holds much promise for evaluating the quality of synthetic Korean speech.

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