• 제목/요약/키워드: hypothesis

검색결과 6,310건 처리시간 0.027초

Biological Network Evolution Hypothesis Applied to Protein Structural Interactome

  • Bolser, Dan M.;Park, Jong Hwa
    • Genomics & Informatics
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    • 제1권1호
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    • pp.7-19
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    • 2003
  • The latest measure of the relative evolutionary age of protein structure families was applied (based on taxonomic diversity) using the protein structural interactome map (PSIMAP). It confirms that, in general, protein domains, which are hubs in this interaction network, are older than protein domains with fewer interaction partners. We apply a hypothesis of 'biological network evolution' to explain the positive correlation between interaction and age. It agrees to the previous suggestions that proteins have acquired an increasing number of interaction partners over time via the stepwise addition of new interactions. This hypothesis is shown to be consistent with the scale-free interaction network topologies proposed by other groups. Closely co-evolved structural interaction and the dynamics of network evolution are used to explain the highly conserved core of protein interaction pathways, which exist across all divisions of life.

Default Bayesian hypothesis testing for the scale parameters in nonregular Pareto distributions

  • Kang, Sang Gil
    • Journal of the Korean Data and Information Science Society
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    • 제23권6호
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    • pp.1299-1308
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    • 2012
  • This article deals with the problem of testing the equality of the scale parameters in nonregular Pareto distributions.We propose Bayesian hypothesis testing procedures for the equality of the scale parameters under the noninformative prior. The noninformative prior is usually improper which yields a calibration problem that makes the Bayes factor to be de ned up to a multiplicative constant. So we propose the default Bayesia hypothesis testing procedures based on the fractional Bayes factor and the intrinsic Bayes factors under the reference priors. Simulation study and a real data example are provided.

A Study on Students Scientific Reasoning in Solving Pendulum Task

  • Yang, Il-Ho
    • 한국과학교육학회지
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    • 제23권4호
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    • pp.430-441
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    • 2003
  • The purpose of this study was to investigate the effects of students' prior knowledge on scientific reasoning in solving a pendulum task with a computer simulation. Subjects were 60 Korean students: 27 fifth-grade students from an elementary school and 33 seventh grade students from a middle school located in a city with 300,000 people. This study adapted a pendulum task presented with a computer simulation on which subjects would use a pattern of multivariable causal inferences. The subjects were interviewed individually in a three-phase structured interview by the researcher and three assistants while he/she was investigating the pendulum task. This study showed that most students across grades focused heavily on demonstrating the primacy of their prior knowledge or their current hypothesis. In addition, students' theories that are part of one's prior knowledge have a significant impact on formulating, testing, and revising hypotheses. Therefore, this study supported the notion that students' prior knowledge had a strong effect on students' experimental intent and hypothesis evaluation.

Impostor Detection in Speaker Recognition Using Confusion-Based Confidence Measures

  • Kim, Kyu-Hong;Kim, Hoi-Rin;Hahn, Min-Soo
    • ETRI Journal
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    • 제28권6호
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    • pp.811-814
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    • 2006
  • In this letter, we introduce confusion-based confidence measures for detecting an impostor in speaker recognition, which does not require an alternative hypothesis. Most traditional speaker verification methods are based on a hypothesis test, and their performance depends on the robustness of an alternative hypothesis. Compared with the conventional Gaussian mixture model-universal background model (GMM-UBM) scheme, our confusion-based measures show better performance in noise-corrupted speech. The additional computational requirements for our methods are negligible when used to detect or reject impostors.

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Cholesterol, Statins, and Brain Function: A Hypothesis from a Molecular Perspective

  • Shin, Yeon-Kyun
    • Interdisciplinary Bio Central
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    • 제1권1호
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    • pp.2.1-2.3
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    • 2009
  • There is evidence that cholesterol in the brain plays an important role in the neurotransmitter release. A decrease of the cholesterol level severely hampers the activity of the membrane fusion machinery, thereby inhibiting the release. Meanwhile, the results from several clinical studies suggest that a low cholesterol level is linked to the dysfunction of some brain activities. Because the neurotransmitter release underlies the basic brain function, the combined results lead to a testable hypothesis that the cholesterol-lowering drugs may inhibit the neurotransmitter release at the synapse. Such inhibition of the release could result in impaired brain function for a limited group of people. A molecular basis for the hypothesis is discussed.

Android App Reuse Analysis using the Sequential Hypothesis Testing

  • Ho, Jun-Won
    • International Journal of Internet, Broadcasting and Communication
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    • 제8권4호
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    • pp.11-18
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    • 2016
  • Due to open source policy, Android systems are exposed to a variety of security problems. In particular, app reuse attacks are detrimental threat to the Android system security. This is because attacker can create core malign components and quickly generate a bunch of malicious apps by reusing these components. Hence, it is very imperative to discern whether Android apps contain reused components. To meet this need, we propose an Android app reuse analysis technique based on the Sequential Hypothesis Testing. This technique quickly makes a decision with a few number of samples whether a set of Android apps is made through app reuse. We performed experimental study with 6 malicious app groups, 1 google and 1 third-party app group such that each group consists of 100 Android apps. Experimental results demonstrate that our proposed analysis technique efficiently judges Android app groups with reused components.

LNAPL을 이용한 지중 산소전달 향상: (I) Abiotic Condition (Effect of pH and Iron/Manganese Ion on TiO2 Mediated Photocatalytic Inactivation of Index Microorganisms)

  • 하정협;강선홍
    • 상하수도학회지
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    • 제18권3호
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    • pp.307-311
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    • 2004
  • The objective of this work is to evaluate the hypothesis that a good technique for supplying oxygen to the saturated zone in the presence of light nonaqueous phase liquid (LNAPL) pool contamination at the water table is to pass air through the unsaturated zone above the pool. This hypothesis was evaluated in experimental studies performed using a bench-scale, sand-tank reactor, Steady-state abiotic experiments in the sand-tank reactor with air flowing through the reactor headspace demonstrated that oxygen supply through the water table interface into the saturated zone was enhanced when an LNAPL (dodecane) pool was present at the water table. These experimental results confirmed the hypothesis that an LNAPL pool can serve as a high concentration oxygen source to the oxygen-limited area beneath the pool and, as a result, enhance the in situ biodegradation rate.

Default Bayesian hypothesis testing for the scale parameters in the half logistic distributions

  • Kang, Sang Gil;Kim, Dal Ho;Lee, Woo Dong
    • Journal of the Korean Data and Information Science Society
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    • 제25권2호
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    • pp.465-472
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    • 2014
  • This article deals with the problem of testing the equality of the scale parameters in the half logistic distributions. We propose Bayesian hypothesis testing procedures for the equality of the scale parameters under the noninformative priors. The noninformative prior is usually improper which yields a calibration problem that makes the Bayes factor to be dened up to a multiplicative constant. Thus we propose the default Bayesian hypothesis testing procedures based on the fractional Bayes factor and the intrinsic Bayes factors under the reference priors. Simulation study and an example are provided.

국부 확률을 이용한 데이터 분류에 관한 연구 (A Study on Data Clustering Method Using Local Probability)

  • 손창호;최원호;이재국
    • 제어로봇시스템학회논문지
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    • 제13권1호
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    • pp.46-51
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    • 2007
  • In this paper, we propose a new data clustering method using local probability and hypothesis theory. To cluster the test data set we analyze the local area of the test data set using local probability distribution and decide the candidate class of the data set using mean standard deviation and variance etc. To decide each class of the test data, statistical hypothesis theory is applied to the decided candidate class of the test data set. For evaluating, the proposed classification method is compared to the conventional fuzzy c-mean method, k-means algorithm and Discriminator analysis algorithm. The simulation results show more accuracy than results of fuzzy c-mean method, k-means algorithm and Discriminator analysis algorithm.

Theoretical Problems behind Teaching English in Elementary Schools

  • Pak, Yunhwa
    • 한국영어학회지:영어학
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    • 제1권3호
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    • pp.437-456
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    • 2001
  • This paper raises a question on the theoretical background behind the English education at the elementary school level. The Critical Period Hypothesis (CPH), supporting the common belief of the earlier the better in foreign language learning, which has promoted the strong trend toward teaching English in Korean elementary schools, is analyzed to determine whether it provides a comprehensible picture to explain age-related factors and whether it is a valid hypothesis which can be applicable in an EFL situation such as Korea. This paper concludes that CPH itself is still considered as an impending hypothesis full of unresolved issues and that the present educational situation of Korean elementary schools is rather far from the environment in which the ideas of CPH could practically apply, and thus it may be desirable to find alternative theoretical backgrounds from which the educational programs can be developed and further expanded.

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