• Title/Summary/Keyword: power-laws

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Design of Instruction Helping 8th Grade Students Discover the Power Laws and its Application (중학교 2학년 학생들의 지수법칙 발견을 위한 교수 설계 및 적용)

  • Kang, Jeong-Gi
    • Journal of Educational Research in Mathematics
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    • v.27 no.2
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    • pp.171-189
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    • 2017
  • By designing and applying the lesson helping to discover the power laws, we tried to investigate the characteristics on the class. To do this, we designed a discovery lesson on the power laws and applied to 54 8th grade students. As results, we could observe the overproduction of monotonous laws, tendency to vary the type of development and increase error to students without prior learning experience, and various errors. All participants failed to express the generalization of $a^m{\div}a^n$ and some participants expressed an incomplete generalization using variables partially for the base or power. We could also observe an error of limited generality or a representation error which did not use the equal sign or variables. In the survey of students, there were two contradictory positions to appeal to the enjoyment of the creation and to talk about the difficulty of creation. Based on such results, we discussed the pedagogical implications relating to the discovery of power laws.

Preparation of the Applicable Regulatory Guideline on Mixed Waste in Korea Based on the Analysis of US Laws and Regulations

  • Sim, Eun-Jin;Lee, Sun-Kee;Kim, Chang-Lak;Kim, Tae-Man
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.19 no.1
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    • pp.141-160
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    • 2021
  • Unit 1 of the Kori Nuclear Power Plant (NPP) and Unit 1 of the Wolsong NPP are being prepared for decommissioning; their decommissioning is expected to generate large amounts of intermediate-level, low-level, and very low level Waste. Mixed waste containing both radioactive and hazardous substances is expected to be produced. Nevertheless, laws and regulations, such as the Korean Nuclear Safety Act and Waste Management Act, do not define clear regulatory guidelines for mixed waste. However, the United States has strictly enforced regulations on mixed waste, focusing on the human health and environmental effects of its hazardous components. The U.S. Nuclear Regulatory Commission and the U.S. Department of Energy regulate the radioactive components of mixed waste under the Atomic Energy Act. The U.S. Environmental Protection Agency regulates the hazardous waste component of mixed waste under the Resource Conservation and Recovery Act. In this study, the laws, regulations, and authorities pertaining to mixed waste in the United States are reviewed. Through comparison and analysis with waste management laws and regulations in Korea, a treatment direction for mixed waste is suggested. Such a treatment for mixed waste will increase the efficiency of managing mixed waste when decommissioning NPPs in the near future.

Investigation of the Sensitivity Depletion Laws for Rhodium Self-Powered Neutrorn Detectors (SPNDs)

  • Kim, Gil-Gon;Cho, Nam-Zin
    • Nuclear Engineering and Technology
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    • v.33 no.2
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    • pp.121-131
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    • 2001
  • An investigation of the sensitivity depletion laws for rhodium SPNDs was performed to reduce the uncertainty of the sensitivity depletion laws used in Combustion Engineering (CE) reactors and to develop calculational tools that provide the sensitivity depletion laws to interpret the signal of the newly designed rhodium SPND into the local neutron flux. The calculational tools developed in this work are computer programs for a time-dependent neutron flux distribution in the rhodium emitter during depletion and for a time-dependent beta escape probability that a beta particle generated in the emitter escapes into the collector. These programs provide the sensitivity depletion laws and show the reduction of the uncertainty by about 1 % compared to that of the method employed by CE in interpreting the signal into the local neutron flux. A reduction in the uncertainty by 1 % in interpreting the signal into the local neutron flux reduces the uncertainty tv about 1 % in interpreting the signal into the local power and lengthens the lifetime of the rhodium SPND by about 10% or more.

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THE CONVERGENCE RATES IN THE ASYMMETRIC LAWS OF LARGE NUMBER FOR NEGATIVELY ASSOCIATED RANDOM FIELDS

  • Ko, Mi-Hwa
    • Honam Mathematical Journal
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    • v.34 no.2
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    • pp.209-217
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    • 2012
  • Convergence rates in the law of large numbers for i.i.d. random variables have been generalized by Gut[Gut, A., 1978. Marc inkiewicz laws and convergence rates in the law of large numbers for random variables with multidimensional indices, Ann. Probab. 6, 469-482] to random fields with all indices having the same power in the normalization. In this paper we generalize these convergence rates to the identically distributed and negatively associated random fields with different indices having different power in the normalization.

Similitudes for the structural response and radiated sound power of simply supported plates

  • Robin, Olivier;Margherita, Pasquale;De Rosa, Sergio;Berry, Alain;Franco, Francesco;Ciappi, Elena
    • Advances in aircraft and spacecraft science
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    • v.6 no.6
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    • pp.443-461
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    • 2019
  • This communication investigates exact and distorted similitudes and the related scaling laws for the analysis of both dynamic response and radiated power of rectangular plates. The response of a given panel in similitude from another one is determined from a generalization of the modal approach, allowing the use of mode shapes, natural frequencies and finally radiation functions in order to establish appropriate scaling laws. Analytical models of simply supported rectangular plates are used to produce both original and replica model responses under point mechanical excitation. Emphasis is then especially put on laboratory experiments which are performed on baffled simply supported aluminum panels under mechanical excitations. All the six possible scaling directions, i.e. predicting a plate vibroacoustic reponse from another plate, are reported. All obtained results show that structural response or radiated sound power of a given plate can be both recovered with satisfactory accuracy by using the related scaling laws, even if parent models are used.

Power-Laws Exponents of the Domestic AS-level Internet Topology based on the Valley-free BGP Routing Policy (BGP 밸리-프리 라우팅 정책에 기반한 국내 AS 레벨 인터넷 토폴로지의 파워-로 지수)

  • Kang, Koo-Hong
    • Journal of Internet Computing and Services
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    • v.11 no.4
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    • pp.41-49
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    • 2010
  • Faloustsos et al.[1,2] showed successfully that the power-laws describe the heavy-tailed distributions of the AS level Internet topology properties such as node degree. This result allows us to represent the characteristics of AS-level Internet topology using some power-law exponents with elegant and simple. In this paper, we obtained the power-law exponents of the domestic AS-level Internet topology properties - the node degree, the number of pairs within hops, and eigenvalues of the graph - based on the valley-free BGP routing policy. We used the real data sets from UCLA IRL laboratory, and showed that these power-laws fit the real data pretty well resulting in correlation coefficient of 90.7%, 96.5%, and 97%, respectively. In particular, rounding the effective diameter to three, approximately 91% of the pairs of nodes are within this distance; that is, we might conclude our topology is pretty well organized.

FG-based computational fracture of frequency up-conversion for bistablity of rotating shell: An effective numerical scheme

  • Hussain, Muzamal
    • Advances in concrete construction
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    • v.13 no.5
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    • pp.367-376
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    • 2022
  • Theoretical study of vibration distinctiveness of rotating cylindrical are examined for three volume fraction laws viz.: polynomial, exponential and trigonometric. These laws control functionally graded material composition in the shell radius direction. Functionally graded materials are controlled from two or more materials. In practice functionally graded material comprised of two constituent materials is used to form a cylindrical shell. For the current shell problem stainless steel and nickel are used for the shell structure. A functionally graded cylindrical shell is sanctioned into two types by interchanging order of constituent materials from inner and outer side for Type I and Type II cylindrical shell arrangement. Fabric composition of a functionally graded material in a shell thickness direction is controlled by volume fraction law. Variation of power law exponent brings change in frequency values. Influence of this physical change is investigated to evade future complications. This procedure is capable to cater any boundary condition by changing the axial wave number. But for simplicity, numerical results have been evaluated for clamped- simply supported rotating cylindrical shells. It has been observed from these results that shell frequency is bifurcated into two parts: one is related to the backward wave and other with forward wave. It is concluded that the value of backward frequency is some bit higher than that forward frequency. Influence of volume fraction laws have been examined on shell frequencies. Backward and forward frequency curves for a volume fraction law are upper than those related to two other volume fraction laws. The results generated furnish the evidence regarding applicability of present shell model and also verified by earlier published literature.

Citation Laws and Quasi-Impact Factor on Innovation Studies in Korea (한국기술혁신연구의 인용문헌 법칙과 의사 영향력지수)

  • Park, Jun-Min;Seol, Sung-Soo;Nanm, Su-Hyeon
    • Journal of Information Management
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    • v.40 no.4
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    • pp.135-150
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    • 2009
  • Existing bibliometric laws have been established on the basis of well defined science journals with a long history. However, the history of technology innovation research in Korea is young and the scope of the research is diverse compared with other fields. The main purpose of this research can be summarized as follows : Can the traditional bibliometric laws be used to explain the young and diverse data derived from technology innovation studies in Korea. Second, we want to compare the explain ability of the power law, compared with the traditional laws in the field. Third, we propose a quasi index related to the well-known impact factor to measure the contribution of a journal or a group of journals to the development of innovation research in Korea. We confirmed Lotka's and Bradford's laws which are used to measure the productivity of researchers, but we could not support the validity of Price's Square Root law as Nicholls (1998) could not. On the citations to journals, Garfield's laws is not observed. However, the power law fits well the citations to author, journal, article, and book. The estimated parameters between 1.6 and 3.5 are similar to the values in the range of 1.5 and 3 in previous studies. Finally the quasi index shows that the influence of international leading journals on innovation research in Korea is weaker than on innovation studies in the world.