• Title/Summary/Keyword: Length of Sample

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Choosing between the Exact and the Approximate Confidence Intervals: For the Difference of Two Independent Binomial Proportions

  • Lee, Seung-Chun
    • Communications for Statistical Applications and Methods
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    • v.16 no.2
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    • pp.363-372
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    • 2009
  • The difference of two independent binomial proportions is frequently of interest in biomedical research. The interval estimation may be an important tool for the inferential problem. Many confidence intervals have been proposed. They can be classified into the class of exact confidence intervals or the class of approximate confidence intervals. Ore may prefer exact confidence interval s in that they guarantee the minimum coverage probability greater than the nominal confidence level. However, someone, for example Agresti and Coull (1998) claims that "approximation is better than exact." It seems that when sample size is large, the approximate interval is more preferable to the exact interval. However, the choice is not clear when sample, size is small. In this note, an exact confidence and an approximate confidence interval, which were recommended by Santner et al. (2007) and Lee (2006b), respectively, are compared in terms of the coverage probability and the expected length.

Measurement of Acoustic Properties and Prediction of Acoustic Performance of Porous Woven Hoses for Engine Intake Systems (엔진 흡기계에 쓰이는 다공형 직조관의 음향특성 측정 및 성능예측)

  • Park, C.M.;Ih, J.G.;Nakayama, Y.;Kitahara, S.;Takao, H.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.11a
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    • pp.182-186
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    • 2000
  • The porous woven hose is recently considered as an effective element of automotive intake systems. In order to predict the acoustic performance of an intake system with a porous woven hose, the information on the acoustic wall impedance is required. In this article, a measurement technique that is valid over the low frequency range and without mean flow condition is presented. The measurement is performed in a cylindrical chamber with a concentric layout of the sample and the resistance is estimated from measured reactance and transmission loss data. It is observed that the measured transmission loss for a porous woven hose with an arbitrary length agrees well with the predicted one that uses the estimated impedance for a small sample length.

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Experimental study on the correlation between measurement length and winding or twist pitch for magnetization loss occurring in CORC and TSTC

  • Ji-Kwang Lee;Jinwoo Han;Kyeongdal Choi;Woo-Seok Kim
    • Progress in Superconductivity and Cryogenics
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    • v.25 no.4
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    • pp.40-44
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    • 2023
  • For high-temperature superconducting power applications that need large current capacity, a large current conductor manufactured using multiple superconducting tape is required. Conductors being studied for large currents capacity such as CORC, TSTC, and RACC have advantages and disadvantages, and in order to use these conductors in coil form and apply them to AC power devices, research on magnetization loss occurring in superconductors due to external magnetic fields is essential. To accurately measure magnetization loss in a conductor that is twisted by stacking straight conductors like TSTC, the correlation between the measuring system and the shape of the sample must be clearly known to accurately measure the loss. In this paper, we will confirm the difference in magnetization loss measurement values according to the correlation between the length of the pickup coil and the twist pitch of the sample in CORC and TSTC shapes, and review considerations for accurate magnetization loss measurement from the results.

On the Length of Sample Sequence in Universal Statistical Test (유니버설 통계적 검정에서 표본 수열의 길이에 대한 분석)

  • 강주성
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.8 no.3
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    • pp.105-114
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    • 1998
  • Maurer가 제안한 유니버설 통계적 검정을 소개하고 검정에 사용된 통계량의 의미를 분석한다. 기존 검정법을 포괄하는 이 검정법은 보다 넓은 의미의 통계적 결점들을 탐지해낼 수 있다. 또한, 검정에 사용되는 통계량은 엔트로피와 밀접한 연관이 있으며 암호학적 응용에서 시스템의 안전성에 영향을 키치는 요소들을 탐지해 낸다. 이러한 특징과 함께 기존 검정법 보다 상당히 긴 표본 수열을 필요로 한다는 사실이 유니버설 검정의 단점으로 지적되어 왔다. 그러나 본 논문에서는 빈도(freequency) 검정법과의 비교를 통해서 미세한 편의(bias)를 탐지해내기 위한 도구로서는 유니버설 검정이 오히려 더 효율적이라는 사실을 보였다.

Physicochemical Properties of Commercial Salrt-Fermented Shrimp (시판 새우젓의 이화학적 특성)

  • 황종현;김진만
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.4
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    • pp.760-763
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    • 2001
  • Five commercial salt-fermented shrimps contained 29.8~48.3% of salt 3.5%~7.3% of total nitrogen and 0.3~0.7g/100g of amino-nitrogen respectively. The average peptide length(APL) of five commercial salt-fermented shrimps ranged from 10.1 to 15.0. Sample B and E showed longer APL than the others with the values of 15.0 and 14.4 respectively. Protease activity showed the large differences in five samples from 17 unit to 232 unit ; sample C showed the highest protease activity with 232 unit while sample D and E were relatively lower with 17 unit and 18 unit respectively. The chitinase activities which can hydrolyze chitin the one of components on outer layer of shrimp ranged from 14.4 unit to 171 unit. Sample E had the highest chitinase activity as 171 unit but sample B showed the lowest activity with 14.4 unit. Chitooligosaccharides of five commercial salted-fermented shrimps were consisted of monoglucosamine diglucosamine and triglucosamine.

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An analytical investigation of soil disturbance due to sampling penetration

  • Diao, Hongguo;Wu, Yuedong;Liu, Jian;Luo, Ruping
    • Geomechanics and Engineering
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    • v.9 no.6
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    • pp.743-755
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    • 2015
  • It is well known that the quality of sample significantly determines the accuracy of soil parameters for laboratory testing. Although sampling disturbance has been studied over the last few decades, the theoretical investigation of soil disturbance due to sampling penetration has been rarely reported. In this paper, an analytical solution for estimating the soil disturbance due to sampling penetration was presented using cavity expansion method. Analytical results in several cases reveal that the soil at different location along the sample centerline experiences distinct phases of strain during the process of sampling penetration. The magnitude of induced strain is dependent on the position of the soil element within the sampler and the sampler geometry expressed as diameter-thickness ratio D/t and length-diameter ratio L/D. Effects of sampler features on soil disturbance were also studied. It is found that the induced maximum strain decreases exponentially with increasing diameter-thickness ratio, indicating that the sampling disturbance will reduce with increasing diameter or decreasing wall thickness of sampler. It is also found that a large length-diameter ratio does not necessarily reduce the disturbance. An optimal length-diameter ratio is suggested for the further design of improved sampler in this study.

The Sleeve Knitting Method of the Seamless Knit One-Piece Dress - Focused on the Bind-off Length at the Axilla - (무봉제 니트 원피스 드레스의 소매 편성 방법 - 겨드랑 부위의 바인드 오프 처리 분량을 중심으로 -)

  • Lee, Mi-Sook;Kim, Myoung-Ok;Suh, Mi-A
    • The Research Journal of the Costume Culture
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    • v.17 no.6
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    • pp.1059-1067
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    • 2009
  • The knitting method of the sleeves for improving movement adaptability were studied in this paper. The purpose of this study is proposing a knitting method that is suitable for the bodies of women in their 20's and can enhance wearing satisfaction. To see the effect of the bind-off length at the axilla, a movement adaptability test was undertaken for 4 samples that have bind-off at bodices. In addition to that, the analysis of their sliding distance with respect to the human motions were executed. The results of this study were listed below. Its result was that the samples with small bind-off lengths represent better wearing satisfaction than the samples which have large bind-off lengths. The comparison of the sliding distances at the hem, waist and sleeves with respect to the tester's motions also shows that the sample having small bind-off makes better result than the sample with large bind-off. It was observed that the optimal length of bind-off was 2cm for the improvement of the sleeve functionality.

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On the Total Length and Body Weight of the File File Fish , Navodos Modestus Caught in the Sonthern Sea Area of Komundo Is . During Summer (여름철 거문도 남부해역에서 어획된 말쥐치의 체장과 체중 조성)

  • 염말구
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.22 no.4
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    • pp.71-74
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    • 1986
  • The author tried to clarify the distribution of the total length and body weight of the file h, Navodos modcstus, caught by trawl net during July, 1984 in the southern sea korea. Among the catches of five times fishing operation, 1540 individuals were randomly sampled for the measurement. The results are summarized as follows; " The distribution of total length showed bimodal type, wbich was able to analyzed into two normal distributions N(17.46, 1. 02^2) and N(22.09, 1. 77^2). And smaller group was much than older one. The age of the sample estimated from the total length distribution of. smaller group was 1. 5 to 2, and the larger group 2. 5 to 4. The relationship between the total length and the body weight can be presented as following equation: $$W=0.01726 L^{2.8507}$$ ' or $$W= 0.01109 L^{3.0}$$ or $$W= 0.01109 L^{3.0}$$.

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Fabrication of 100m Class Bi-2223 High Temperature Superconductir (100m급 Bi-2223 고온초전도 선재 제조)

  • 하홍수;오상수;하동우;장현만;이남진;이준석;정대영;류강식
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 1999.02a
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    • pp.10-13
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    • 1999
  • For large scale applications of high temperature superconductor(HTS) such as transmission cables, motors and generators, long length of flexible HTS conductors is required. Currently, HTS tape that is capable of being fabricated in long length by industrial processes is the Bi-2223 HTS tape. In this study, we fabricated 19 filamentary Bi-2223($Bi_{1.8}$$Pb_{0.4}$$Sr_{2}$$Ca_{2}$$Cu_{3}$$O_{10+X}$) HTS tape with 100m length by PIT(Powder In Tube) process. Critical current(Ic) of this long length tape was measured 18.5 A at 77 K, self field and short sample Ic is 32.5 A at the same condition. Critical current of 100m length tape was decreased by about 1/3 compared to that of short tape. This was mainly resulted from the increase of non homogeneity in oxide layer.

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The Changes of Korean Pop Music through Digital Music Industry (디지털음악시장을 통해 살펴본 국내 대중가요의 변화)

  • Park, Byung-Kyu
    • Journal of Digital Contents Society
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    • v.13 no.2
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    • pp.177-187
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    • 2012
  • This research considers growth of digital music industry and the consequential changes in the environment of music consumption, and how environment of purchasing digital music has influenced music's length and forms. Meaningful data such as average length of music, average time taken to chorus, appearance of intro, interlude, outro, and precedence of chorus has been collected from K-Pop of 2000 to 2011 through this research. Result has shown music sample streaming service in internet music industry has brought changes in music's length and formation, which leaded to birth of hook songs. Through this case of consumer's environmental influence on music, research predicts music industry will look forward to achieving techniques to deliver music more effectively by adopting the content's download-based internet environment.