• Journal of Korea Water Resources Association
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• v.49 no.6
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• pp.495-507
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• 2016

This study aims at hydrologically demonstrating the universality of power law distribution by analyzing runoff aggregation structures of river basins. Power law distribution is fitted to cumulative drainage area of basins of interest by maximum likelihood, which results in the power law exponents. And then those exponents are assessed in terms of the shape of catchment plan-form. As a main result all of the basins in this study have similar distributions of catchment area. The exponents from this study tend to be higher than the ones from previous researches reflecting self-similar property of the catchment plan-forms of interest. Further study is required about the universality of power law distribution by means of the more realistic flow routing scheme within the framework of DEM.

• Journal of Korea Water Resources Association
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• v.50 no.11
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• pp.725-734
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• 2017

The main purpose of this study is to analyze runoff aggregation structure and energy expenditure pattern of Choyang creek basin within the framework of power law distribution. To this end geomorphologic factors of every point in the basin of interest, which define tractive force and stream power as well as drainage area, are extracted based on GIS, and their complementary cumulative distributions are graphically analyzed through fitting them to power law distribution. The results indicate that three distinct behavioral regimes are observed from the complementary cumulative distributions of three geomorphogic factors. Based on the parameter estimation of power law distribution by maximum likelihood drainage area and stream power can be judged as scale invariance factor without finite scale while tractive force as scale dependence factor with finite scale. Furthermore, it is judged that tractive force would not follow power law distribution because it shows limited complex system behaviors only within the small extent of scale. The exponent of power law distribution for drainage area obtained in this study by maximum likelihood is larger than the previous researches due to the difference of parameter estimation methodologies. And the exponent for stream power is smaller than the previous researches due to the scaling property of channel slope for the basin of interest.

• 한국IT서비스학회:학술대회논문집
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• 2007.11a
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• pp.131-135
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• 2007

참여의 멱함수 이론은 UCC를 생산, 배포, 소비, 재생산하는 과정에 참여하는 사용자들을 분석하는 유용한 도구이다. 참여의 멱함수 이론을 통해 무리는 집합적 지성과 집단 지성을 구분하고 참여의 형태를 세분화하며 참여자간의 관계 분석할 수 있다. 즉 다양한 기술, 사회, 정치 현상들에 배경 정보가 되어 영향력을 행사하는 UCC는 어떤 이유로 제작되고 어떤 형태로 나누어지며 생산한 사람들 간의 관계 또는 생산자와 생산자 고리고 생산자와 소비자 간의 관계를 설명할 때 설득력들 높인다. UCC가 웹 2.0의 어떤 기술 속에 생산되고 배포되고 소비되는지에 대한 플랫폼의 설계에도 멱함수 법칙은 도움을 주는 도구이다.

• Journal of Digital Contents Society
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• v.9 no.2
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• pp.325-330
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• 2008

Production and distributon of UCC prepared User of UCC. Power law of participation is available tool for analysis of UCC user. We can devide collective intelligence and collaborative intelligence through power law of participation. We can analyze relation of paticipant and departmentalize type of participation, Power law of participation is available tool for platform design of production and distribution.

• Journal of Korea Water Resources Association
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• v.51 no.3
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• pp.235-246
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• 2018

The main purpose of this study is to suggest a methodology for identifying vulnerable region in Choyang creek basin susceptible to soil losses based on runoff aggregation structure and energy expenditure pattern of natural river basin within the framework of power law distribution. To this end geomorphologic factors of every point in the basin of interest are extracted by using GIS, which define tractive force and stream power as well as drainage area, and then their complementary cumulative distributions are graphically analyzed through fitting them to power law distribution to identify the sensitive points within the basin susceptible to soil losses with respect to scaling regimes of tractive force and stream power. It is observed that the range of vulnerable region by scaling regime of tractive force is much narrower than by scaling regime of stream power. This result seems to be due to the tractive force is a kind of scale dependent factor which does not follow power law distribution and does not adequately reflect energy expenditure pattern of river basins. Therefore, stream power is preferred to be a more reasonable factor for the evaluation of soil losses. The methodology proposed in this study can be validated by visualizing the path of soil losses, which is generated from hill-slope process characterized by local slope, to the valley through fluvial process characterized by drainage area as well as local slope.

• Journal of Korean Library and Information Science Society
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• v.44 no.4
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• pp.399-419
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• 2013

This paper conducted the empirical analysis of the behaviors revealed in the eight size distributions of the public libraries in Korea. As a result, the behaviors of complex system appeared in all eight size factors. This means that the sizes of public libraries in Korea were highly polarized. Especially, the zipf's law were found in the size factors such as gross area, number of staffs, volume of books, total budget. And the highly uneven distributions were occurred in the size factors such as membership, number of users, number of borrowers, number of borrowed books. This research outcomes show that a new policy of public libraries is needed to resolve the polarization revealed in the sizes of public libraries in Korea.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.274-274
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• 2016

일반적으로 수공구조물의 설계지점은 홍수량 자료가 없는 경우가 대부분이다. 이러한 미계측유역의 홍수빈도를 추정하기 위한 여러방법들 중 지수홍수법을 이용한 지역홍수빈도분석을 본 연구에서 수행하였다. 특히, 지수홍수법의 주요인자 중 하나인 평균홍수량의 지역화를 위한 방법으로 홍수량과 유역면적과의 관계가 멱함수 법칙(power law)을 따른다는 가정에 따른 경험관계를 도출하였다. 보다 세밀한 분석을 위해 대상유역 전체를 하나의 그룹, 공간 근접성에 따른 추가적인 세부적인 그룹으로 분류하여 각각의 결과를 분석하였다. 연구결과에 의하면, 미계측 지점의 홍수량 추정시에는 인근의 계측지역 즉, 직상하류 유역의 비유량의 관계를 사용하는 것이 타당할 것으로 판단된다. 또한 미계측 유역에 대한 홍수빈도를 추론하기 위해서는 지역홍수빈도해석 자체도 중요하지만, 지역의 세밀한 구분과 그에 따른 지역화 경험관계 개발이 중요함을 확인할 수 있었다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.5
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• pp.553-561
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• 2015

The exponential and power law functionally graded material(FGM) theory is reformulated considering the refined shear and normal deformation theory. This theory has ability to capture the both normal deformation effect and exponential and power law function in terms of the volume fraction of the constituents for material properties through the plate thickness. Navier's method has been used to solve the governing equations for all edges simply supported plates on Pasternak elastic foundation. Numerical solutions of vibration analysis of FGM plates are presented using this theory to illustrate the effects of power law index and 3-D theory of exponential and power law function on natural frequency. The relations between 3-D and 2-D higher-order shear deformation theory are discussed by numerical results. Further, effects of (i) power law index, (ii) side-to-thickness ratio, and (iii) elastic foundation parameter on nondimensional natural frequency are studied. To validate the present solutions, the reference solutions are discussed.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.1
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• pp.9-16
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• 2014

This paper presents the theoretical analysis of a flow driven by surface tension and gravity in an inclined circular tube. A governing equation is developed for describing the displacement of a non-Newtonian fluid(Power-law model) that continuously flows into a circular tube owing to surface tension, which represents a second-order, nonlinear, non-homogeneous, and ordinary differential form. It was found that quantitatively, the theoretical predictions of the governing equation were in excellent agreement with the solutions of the equation for horizontal tubes and the past experimental data. In addition, the predictions compared very well with the results of the force balance equation for steady.

• 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.