• Title/Summary/Keyword: Science principle

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ATM Rate Based Traffic Control with Bode Principle

  • Jing, Yuanwei;Zeng, Hui;Jing, Qingshen;Yuan, Ping
    • International Journal of Control, Automation, and Systems
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    • v.6 no.2
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    • pp.214-222
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    • 2008
  • Bode principle is applied to carry out traffic control for rate based ATM network, which guarantees the higher buffer utilization, buffer overflow-free, and well utilization of bandwidth. The principle confirms the relationship between the threshold of buffer queue and the network bandwidth, as well as the relationship between the threshold of buffer and source input rate. Theoretic warrant of the buffer threshold is proposed. The reference range of source input rate is provided in theory, which makes the source end respond to the change of network state rapidly and dynamically, and then the effect of time delay to the traffic control is avoided. Simulation results show that the better steady and dynamic performances of networks are obtained by Bode principle.

Operation Principle and Topology Structures of Axial Flux-Switching Hybrid Excitation Synchronous Machine

  • Liu, Xiping;Wang, Chen;Zheng, Aihua
    • Journal of international Conference on Electrical Machines and Systems
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    • v.1 no.3
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    • pp.312-319
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    • 2012
  • The operation principle of an axial flux-switching hybrid excitation synchronous machine (AFHESM) is analyzed and its topology structures are proposed in this paper. After some comprehensive analysis of the operation principle to axial flux electrical machine, flux-switching electrical machine and hybrid excitation electrical machine, the operation principle of AFHESM is given. Combined with some typical topological structures of hybrid excitation electrical machine, some possible topological structures are proposed and some comprehensive comparisons are carried out. The analysis results show that the stator-separated AFHESM has some advantages such as less AM turns, less impact on the demagnetization of PM, less magnetic flux-leakage and higher efficiency compared to other topologies.

A Study on Tetrahedron's Properties related with Intersection of Segments and Planes Using the Principle of the Lever (사면체에서 지렛대의 원리를 이용한 선분들 및 평면들의 교차에 관한 성질 연구)

  • Lee, Kwang-Rok;Son, Jin-O;Song, A-Rom;Baek, Soo-Hean;Chung, Ki-Young;Han, In-Ki
    • Communications of Mathematical Education
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    • v.21 no.4
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    • pp.663-676
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    • 2007
  • In this paper we study tetrahedron's properties related with intersection of segments and planes using the principle of the lever. We analyze proof method using the principle of the lever, and describe how to prove intersection of segments and planes using the principle of the lever in tetrahedron.

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Is the Precautionary Principle Unscientific?: 'Rationality' of the Precautionary Principle and its Conflicts with Risk Analysis Framework (사전주의의 원칙은 비과학적인가?: 위험 분석과의 논쟁을 통해 본 사전주의 원칙의 '합리성')

  • Ha, Dae-Cheong
    • Journal of Science and Technology Studies
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    • v.10 no.2
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    • pp.143-174
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    • 2010
  • How can a regulatory policy to address potential hazards be made legitimate in the face of scientific uncertainty? The precautionary principle has been gradually regarded as the most persuasive answer to this intricate question in Europe since the 1970s and generally recognized as a guiding principle in international environmental law. This principle, however, has often been subject to diverse concerns and criticisms due to its vague definition. This article tries to elaborate the precautionary principle while reviewing both the validity and unreasonableness of these criticisms over this principle. Then, this article explores the policy relevance of this principle by applying this elaborated definition to the concrete case of risk governance such as the risk assesment of food safety. In the end, this paper emphasizes the fact that the precautionary principle can be applied in the field of risk governance, refuting the argument that the precautionary principle is only a moral attitude or a political position.

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A Study on the Principles of Military Operations Coincident with Modern War (현대전 양상에 부합된 군사작전 원칙에 관한 연구)

  • Lee, Kang-Un;Choi, Sung-Soo
    • Journal of National Security and Military Science
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    • s.7
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    • pp.129-154
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    • 2009
  • The principles of military operations(principles of war) are the fundamental principles ruling warfighting that made based on the experiences of wars from the time of ancient Greeks to the World War II. Recent wars such as Iraq War showed us the change of environment of war and the style of waging a war. It is believed that future war will be executed with the style of Rapid Deceive Operations, Effect Based Operations, Network Centric Operations. Therefor the principles of war which we use should be reconsidered whether it is useful or not in future warfare. By considering the present principles of operation which are using in many countries and analysing the style of waging future war, we suggest new principles of operations : principle of gravity, principle of mass and dispersal, principle of disturbance, principle of speed, principle of paralysis, principle of synchronization and integration, principle of leadership, and principle of information.

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STUDY OF SPECTRAL ENERGY DISTRIBUTION OF GALAXIES WITH PRINCIPAL COMPONENT ANALYSIS

  • Kochi, Chihiro;Nakagawa, Takao;Isobe, Naoki;Shirahata, Mai;Yano, Kenichi;Baba, Shunsuke
    • Publications of The Korean Astronomical Society
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    • v.32 no.1
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    • pp.209-211
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    • 2017
  • We performed Principle Component Analysis (PCA) over 264 galaxies in the IRAS Revised Bright Galaxy Sample (Sanders et al., 2003) using 12, 25, 60 and $100{\mu}m$ flux data observed by IRAS and 9, 18, 65, 90 and $140{\mu}m$ flux data observed by AKARI. We found that (i)the first principle component was largely contributed by infrared to visible flux ratio, (ii)the second principal component was largely contributed by the flux ratio between IRAS and AKARI, (iii)the third principle component was largely contributed by infrared colors.

Best Invariant Estimators In the Scale Parameter Problem

  • Choi, Kuey-Chung
    • Honam Mathematical Journal
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    • v.13 no.1
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    • pp.53-63
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    • 1991
  • In this paper we first present the elements of the theory of families of distributions and corresponding estimators having structual properties which are preserved under certain groups of transformations, called "Invariance Principle". The invariance principle is an intuitively appealing decision principle which is frequently used, even in classical statistics. It is interesting not only in its own right, but also because of its strong relationship with several other proposal approaches to statistics, including the fiducial inference of Fisher [3, 4], the structural inference of Fraser [5], and the use of noninformative priors of Jeffreys [6]. Unfortunately, a space precludes the discussion of fiducial inference and structural inference. Many of the key ideas in these approaches will, however, be brought out in the discussion of invarience and its relationship to the use of noninformatives priors. This principle is also applied to the problem of finding the best scale invariant estimator in the scale parameter problem. Finally, several examples are subsequently given.

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Gregor Mendel and the Seven Genes (2)

  • Tateno, Yoshio
    • Interdisciplinary Bio Central
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    • v.5 no.4
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    • pp.8.1-8.3
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    • 2013
  • Unlike the traditional view, it is not mysterious about how G. Mendel chose the seven characters of the pea, Pisum sativum, that he studied. He first chose the pea that met three conditions he set up and repeated experiments for two years. Apparently, he knew that those characters were controlled by countable elements. Then, he derived the prediction on the basis of his idea about the elements, and selected the seven characters that satisfied the prediction. He knew "no prediction no science". In population genetics the Hardy-Weinberg principle is well known and cited in many papers and books. However, Mendel already derived the same principle in his paper, because he was acquainted also with physics and mathematics. Actually, the principle was trivial when they derived, but not at all when Mendel did. It is also well known that Mendel's laws were forgotten and rediscovered at the term of the 19th century. That may not be true either. His laws were internationally well known before the rediscovery. In fact, the 1881-year version of the Encyclopedia Britannica contains his laws.

Analogical Reasoning and Transfer of Problem Solving Principle (유추적 추리와 문제해결 원리의 전이)

  • Lee, Myung-Ja
    • Journal of The Korean Association For Science Education
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    • v.16 no.4
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    • pp.470-476
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    • 1996
  • The purpose of this study was to investigate how sample story problems should be presented to students to promote their transfer of a comprehensive solution principle to a story problem in a different domain. The variables of interest were example-problem condition, principle learning condition, and recall condition. One hundred and ninety six university students were asked to solve analogical story problems. Contrary to expectations, there were no significant differences between the one-solved-and-one -unsolved problem format and the two-solved-problem format. Also, subjects who were asked to derive a general solution principle did not received higher scores than subjects who were provided with one and subjects who were in the control group. However, the time interval between analog learning and transfer had effect on the subjects' solution of the target problem.

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