• 제목/요약/키워드: Random process variation

검색결과 79건 처리시간 0.026초

복부초음파를 이용한 상완혈(上脘穴)-췌장 수직거리 측정시스템의 재현성 반복성 평가실험-A Pilot Study- (Gage R&R Study on Abdominal Sonography for Measuring Distance from Sangwan (CV13) to Pancreas - A Pilot Study -)

  • 남동현
    • 대한한의진단학회지
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    • 제14권2호
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    • pp.75-84
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    • 2010
  • Objectives: The objective of the current study is to determine whether an ultrasound device system is adequate for measuring distance from Sangwan (CV13) to pancreas. Methods: We recruited 3 healthy young male subjects and 2 sonographers. The each sonographer measured vertical shortest distance from CV13 to pancreas with a ultrasound device three times in random order. Because the total variation could be divided into repeatability, reproducibility and subject-to-subject variation in Gage R&R method, we compared the sources of variation associated with the measurement system with an analysis of variance model. Results & Conclusions: Number of distinct categories is calculated on the basis of standard deviation of subject-to-subject divided by standard deviation of total Gage R&R. If the number of categories is five or more, the measurement system may be acceptable for the analysis of the process. The number of distinct categories of the ultrasound device system for measuring distance from CV13 to pancreas was 6.29. So we concluded that repeatability and reproducibility of the ultrasound device system for measuring distance from CV13 to pancreas was acceptable.

한국 내 물쇠뜨기 6개 집단의 RAPD 변이와 표현형 관계 (RAPD Variation and Phenetic Relationships for Six Populations of Equisetum pratense in Korea)

  • 허만규;최재원;이장섭;진보규;김혜경
    • 생명과학회지
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    • 제24권6호
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    • pp.612-617
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    • 2014
  • 한국 내 물쇠뜨기 여섯 개 자연 집단의 표현형적 유연 관계를 RAPD 마커에 근거하여 집단수준에서 조사하였다. 또한 RAPD로 물쇠뜨기 집단의 유전적 다양성과 집단구조를 분석하였다. 물쇠뜨기는 평균 26.7%의 유전적 다형성을 나타내었다. 물쇠뜨기는 대립유전자좌위당 적은 수의 좌위(1.267)와 유효한 유전자좌위(1.176)를 나타내었다. 물쇠뜨기의 유전적 다양도(H)는 0.102로 유사한 생활사를 가진 다른 종에 비해 낮았다. 전체 유전적 다양도($H_T$)는 0.112(OPD-07)에서 0.445(OPD-16)까지였으며 평균은 0.141이었다. 전체 유전적 다양도에서 집단 내 다양도($H_S$)는 0.102로 낮았다. 이런 낮은 물쇠뜨기의 다양도는 무성적 생식, 작은 집단 크기, 집단화 과정 등으로 설명될 수 있었다. 유전자좌위에 근거한 집단간 분화를 나타내는 다양도는 비율은 OPD-07의 0.129에서 OPD-09에 0.455로 평균은 0.277이었다. 전체 유전적 변이에서 집단간 변이는 27.7%였으며 나머지 변이의 72.3%는 집단 내에 있었다. 본 결과는 물쇠뜨기의 분류학적 연구 및 집단유전학에 기여할 수 있을 것이다.

The genetic structure of taro: a comparison of RAPD and isozyme markers

  • Sharma, Kamal;Mishra, Ajay Kumar;Misra, Raj Shekhar
    • Plant Biotechnology Reports
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    • 제2권3호
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    • pp.191-198
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    • 2008
  • Germplasm characterization and evolutionary process in viable populations are important links between the conservation and utilization of plant genetic resources. Here, an investigation is made, based on molecular and biochemical techniques for assessing and exploiting the genetic variability in germplasm characterization of taro, which would be useful in plant breeding and ex situ conservation of taro plant genetic resources. Geographical differentiation and phylogenetic relationships of Indian taro, Colocasia esculenta (L.) Schott, were analyzed by random amplified polymorphic DNA (RAPD) and isozyme of seven enzyme systems with specific reference to the Muktakeshi accession, which has been to be proved resistant to taro leaf blight caused by P. colocasiae. The significant differentiations in Indian taro cultivars were clearly demonstrated by RAPD and isozyme analysis. RAPD markers showed higher values for genetic differentiation among taro cultivars and lower coefficient of variation than those obtained from isozymes. Genetic differentiation was evident in the taro accessions collected from different regions of India. It appears that when taro cultivation was introduced to a new area, only a small fraction of genetic variability in heterogeneous taro populations was transferred, possibly causing random differentiation among locally adapted taro populations. The selected primers will be useful for future genetic analysis and provide taro breeders with a genetic basis for selection of parents for crop improvement. Polymorphic markers identified in the DNA fingerprinting study will be useful for screening a segregating population, which is being generated in our laboratory aimed at developing a taro genetic linkage map.

Genetic Diversity of Common Reed in Korea Based on Morphological Characteristics and Random Amplified Polymorphic DNA Markers

  • Chu, Hyo-Sub;Cho, Won-Kyong;Rim, Yeong-Gil;Jo, Yeon-Hwa;Kim, Jae-Yean
    • 한국자원식물학회지
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    • 제24권6호
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    • pp.666-674
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    • 2011
  • To elucidate genetic diversity of common reed in Korea, we collected a total of 674 common reed plants from 27 regions in South Korea. Hierarchical clustering using 7 morphological traits divided the 27 common reed populations into 7 groups. Random amplified polymorphic DNA (RAPD) results identified three distinct groups of common reed. Common reed accessions in group I mostly inhabit coastal areas. Group II includes reeds mostly collected from inland areas. Group III consists of common reed accessions collected from inland and coastal areas, suggesting that this group might contain hybrids. In summary, we suggest that parapatric speciation might be an important factor in the genetic diversity of common reed and geographical speciation of common reed that might be also affected by environmental gradients.

A Formal Guidance for Handling Different Uncertainty Sources Employed in the Level 2 PSA

  • Ahn Kwang-Il;Yang Joon-Eon;Ha Jae-Joo
    • Nuclear Engineering and Technology
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    • 제36권1호
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    • pp.83-103
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    • 2004
  • The methodological framework of the Level 2 PSA appears to be currently standardized in a formalized fashion, but there have been different opinions on the way the sources of uncertainty are characterized and treated. This is primarily because the Level 2 PSA deals with complex phenomenological processes that are deterministic in nature rather than random processes, and there are no probabilistic models characterizing them clearly. As a result, the probabilistic quantification of the Level 2 PSA CET / APET is often subjected to two sources of uncertainty: (a) incomplete modeling of accident pathways or different predictions for the behavior of phenomenological events and (b) expert-to-expert variation in estimating the occurrence probability of phenomenological events. While a clear definition of the two sources of uncertainty involved in the Level 2 PSA makes it possible to treat an uncertainty in a consistent manner, careless application of these different sources of uncertainty may produce different conclusions in the decision-making process. The primary purpose of this paper is to characterize typical sources of uncertainty that would often be addressed in the Level 2 PSA and to provide a formal guidance for quantifying their impacts on the PSA Level 2 risk results. An additional purpose of this paper is to give a formal approach on how to combine random uncertainties addressed in the Level 1 PSA with subjectivistic uncertainties addressed in the Level 2 PSA.

Correlation between chloride-induced corrosion initiation and time to cover cracking in RC Structures

  • Hosseini, Seyed Abbas;Shabakhty, Naser;Mahini, Seyed Saeed
    • Structural Engineering and Mechanics
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    • 제56권2호
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    • pp.257-273
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    • 2015
  • Numerical value of correlation between effective parameters in the strength of a structure is as important as its stochastic properties in determining the safety of the structure. In this article investigation is made about the variation of coefficient of correlation between effective parameters in corrosion initiation time of reinforcement and the time of concrete cover cracking in reinforced concrete (RC) structures. Presence of many parameters and also error in measurement of these parameters results in uncertainty in determination of corrosion initiation and the time to crack initiation. In this paper, assuming diffusion process as chloride ingress mechanism in RC structures and considering random properties of effective parameters in this model, correlation between input parameters and predicted time to corrosion is calculated using the Monte Carlo (MC) random sampling. Results show the linear correlation between corrosion initiation time and effective input parameters increases with increasing uncertainty in the input parameters. Diffusion coefficient, concrete cover, surface chloride concentration and threshold chloride concentration have the highest correlation coefficient respectively. Also the uncertainty in the concrete cover has the greatest impact on the coefficient of correlation of corrosion initiation time and the time of crack initiation due to the corrosion phenomenon.

Gene functional analysis of Harmonia axyridis by in vitro transcription

  • Park, Sang-Eun;Youn, Young-Nam
    • 농업과학연구
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    • 제46권3호
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    • pp.471-488
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    • 2019
  • Random genes were screened in two transforming ways to investigate the new genes of a ladybug using the Harmonia axyridis cDNA library stock cell cloned in the LITMUS 28i vector in a previous study. Phenotypic variation was observed after injection of the synthesized double-stranded RNA through the in vitro transcription process. The cDNA library of H. axyridis was transformed into E. coli $DH5{\alpha}$ and 10B competent cells by heat shock. Analysis of the nucleotide sequences of the 42 clones with the insert DNAs revealed that 21 clones were homologous with the genes of insects, and only one clone had a gene from H. axyridis. Thirteen of the 21 insect genes were homologous with genes from coleopteran insects. Fourteen genes were selected, which were identified by the gene screening results, and were synthesized as double-stranded RNA through in vitro transcription. One microgram of the synthesized double-stranded RNA between segments T1 and T2 were injected using a syringe into each anesthetized fourth larvae which were under 2 days old. As a result, a phenotypic variation appeared in the larva injected with the two genes. While the eggs of H. axyridis injected with distilled water hatched out three days after oviposition, the eggs of H. axyridis injected with dsHma 06 did not hatch but become shrivel a week after oviposition. Most of the H. axyridis injected with dsHma 08 died and were unable to complete the pupation or eclosion during ecdysis.

랜덤 선로상의 광 국재현상에 관한 해석(1) : 해의 국재성에 대한 이론적 고찰 (Theoretical analysis of the lightwave localization phenomenon on the random transmission line (part 1) : localization characteristics of the solution of propagation equation)

  • 최영규
    • 한국광학회지
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    • 제14권4호
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    • pp.429-433
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    • 2003
  • 전파정수가 랜덤하게 분포하는 선로 상에서 파동함수의 해의 성질을 고찰함으로써 랜덤한 매질 내의 파동의 국재현상에 대한 이론적 해석을 시도하였다 파동의 국재는 함수의 해가 증대에서 감쇠로 전환하는 과정에서 발생하므로, 먼저 파동의 증대가 감쇠로 전환되는 과정을 이론적으로 규명하기 위하여 2차 파동방정식을 Bragg조건 등을 이용하여 근사적으로 1차 슐뢰딩거의 방정식의 형태로 유도하였다. 그리고 이 방정식이 취할 수 있는 여러 가지 해의 성질과 그 해가 성립하기 위한 조건에 대하여 고찰하였으며, 파동방정식의 해의 국재성과 전파정수의 변동에 대한 관계에 대하여 몇 가지 조건을 조사하였다. 지수형의 해에서 유전율이 $\varepsilon$=(0,0,$\varepsilon$$_{0}$)인 경우 $\varepsilon$$_{0}$는 파동의 위상에 관여하여 국재현상을 일으키는 요소가 된다는 것을 확인하였다.

신뢰성 향상을 위한 듀얼 안티퓨즈 OTP 메모리 채택 D-PUF 회로 (PUF Logic Employing Dual Anti-fuse OTP Memory for High Reliability)

  • 김승열;이제훈
    • 융합보안논문지
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    • 제15권3_1호
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    • pp.99-105
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    • 2015
  • 기존 SRAM 기반 PUF (physical unclonable function)는 난수 생성 및 키교환에 사용된다. SRAM에서 생성된 출력값은 일정하게 유지되어야 하나, 외부 환경에 의해 변화하는 문제가 발생된다. 본 논문은 듀얼 안티퓨즈 OTP (one time programmable) 메모리를 SRAM 기반 PUF에 채택한 새로운 구조의 D-PUF (deterministic PUF) 회로를 제안한다. 제안된 PUF 회로는 SRAM에서 한 번 생성된 출력값을 일정하게 계속 유지시켜 PUF 회로의 신뢰성을 향상시킬 수 있다. 우선, 높은 보안 수준을 갖는 안티퓨즈를 이용하여 OTP 메모리를 구성하였다. SRAM은 크로스 커플 인버터쌍의 미스매치를 이용하여 전원이 들어온 후 초기값을 임의로 생성하고 이를 출력한다. 마스킹된 출력값은 안티퓨즈 OTP ROM(read-only memory)에 난수값으로 프로그램된다. 한번 프로그램된 ROM 값은 되돌려지지도 변화하지도 않는다. 따라서, 제안된 D-PUF 회로는 SRAM의 출력값을 OTP 메모리에 저장시켜 한 번 결정된 PUF 출력값을 계속 유지시킨다. 제안된 D-PUF의 출력은 동작 전압 및 온도 변화 등과 같은 외부 환경 변수에 영향을 받지 않아 신뢰성이 향상된다. 따라서, 제안된 D-PUF는 강력한 오류 정정 코드없이 사용하더라도 안정적인 동작을 수행할 수 있다.

기계 구조의 강건 설계를 위한 최적화 기법의 개발 (Development of an Optimization Technique for Robust Design of Mechanical Structures)

  • 정도현;이병채
    • 대한기계학회논문집A
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    • 제24권1호
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    • pp.215-224
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    • 2000
  • In order to reduce the variation effects of uncertainties in the engineering environments, new robust optimization method, which considers the uncertainties in design process, is proposed. Both design variables and system parameters are considered as random variables about their nominal values. To ensure the robustness of performance function, a new objective is set to minimize the variance of that function. Constraint variations are handled by introducing probability constraints. Probability constraints are solved by the advanced first order second moment (AFOSM) method based on the reliability theory. The proposed robust optimization method has an advantage that the second derivatives of the constraints are not required. The suggested method is examined by solving three examples and the results are compared with those for deterministic case and those available in literature.