• Title/Summary/Keyword: Power-Law Distribution

Search Result 477, Processing Time 0.031 seconds

Spatial Distribution and Sampling Plan for Pink Citrus Rust Mite, Aculops pelekassi (Acari: Eriophyidae) in Citrus Orchard (감귤원에서 귤녹응애 공간분포 분석과 표본조사법 개발)

  • Song, Jeong-Heub;Hong, Soon-Yeong;Lee, Shin-Chan
    • Korean journal of applied entomology
    • /
    • v.51 no.2
    • /
    • pp.91-97
    • /
    • 2012
  • The dispersion indices, spatial pattern and sampling plan for pink citrus rust mite (PCRM), Aculops pelekassi, monitoring was investigated. Dispersion indices of PCRM indicated the aggregated spatial pattern. Taylor's power law provided better description of variance-mean relationship than Iwao's patchiness regression. Fixed-precision levels (D) of a sequential sampling plan were developed using by Taylor's power law parameters generated from PCRM on fruit sample (cumulated number of PCRM in $cm^2$ of fruit). Based on Kono-Sugino's empirical binomial the mean density per $cm^2$ could be estimated from fruit ratio with more than 12 rust mites per $cm^2$: $ln(m)=4.61+1.23ln[-ln(1-p_{12})]$. To determine the optimal tally threshold, the variance (var(lnm)) for mean (lnm) in Kono-Sugino equation was estimated. The lower and narrow ranged change of variance for esimated mean showed at a tally threshold of 12. To estimate PCRM mean density per $cm^2$ at fixed precision level 0.25, the required sample number was 13 trees, 5 fruits per tree and 2 points per fruit (total 130 samples).

Study on Relationship between Discomfort and Body Pressure Distribution on the Seat under Height of Footrest and Angle of Seatpan (발판 높이와 의자밑판 각도에 따른 체압분포 변화와 불편함의 상관성 평가)

  • Park, Dong-Woon;Ahn, Se-Jin;Yoo, Wan-Suk
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.15 no.6
    • /
    • pp.38-43
    • /
    • 2007
  • In this paper, a study is described on finding a relationship between discomfort and body pressure distribution. In the first step, experiments were conducted to find correlation between pressure distribution and discomfort. The experiments of 12 people on 9 seats were performed. In the second step, parameters and correlation coefficients were determined between the measured body pressure distribution and median values of the subjective evaluations of 12 subjects using psychophysical power law.

Effect of porosity distribution rate for bending analysis of imperfect FGM plates resting on Winkler-Pasternak foundations under various boundary conditions

  • Aicha, Kablia;Rabia, Benferhat;Daouadji, Tahar Hassaine;Bouzidene, Ahmed
    • Coupled systems mechanics
    • /
    • v.9 no.6
    • /
    • pp.575-597
    • /
    • 2020
  • Equilibrium equations of a porous FG plate resting on Winkler-Pasternak foundations with various boundary conditions are derived using a new refined shear deformation theory. Different types of porosity distribution rate are considered. Governing equations are obtained including the plate-foundation interaction. This new model meets the nullity of the transverse shear stress at the upper and lower surfaces of the plate. The novel rule of mixture is proposed to describe and approximate material properties of the FG plates with different distribution case of porosity. The validity of this theory is studied by comparing some of the present results with other higher-order theories reported in the literature. Effects of variation of porosity distribution rate, boundary conditions, foundation parameter, power law index, plate aspect ratio, side-to-thickness ratio on the deflections and stresses are all discussed.

Regulation of Unfair Contract Terms in English Law (영법상 불공정계약조항의 구제)

  • Lee, Byung-Mun
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
    • /
    • v.21
    • /
    • pp.3-37
    • /
    • 2003
  • English law accepts the basic principle of freedom of contract that the parties should be free to agree on any terms that they like unless their agreement is illegal or otherwise contrary to public policy because it infringes some public interest. On the other hand, it has been limited for hundreds of years on the basis that certain contract terms, particularly in standard form, may alter a distribution of risks that the customer would reasonably intended. The alteration may often result from his simple ignorance caused by either lack of opportunity to become aware of clauses or inability to understand their full potential implications. In addition, it may also result from disparity in bargaining power which does not allow the customer to look after their own interests even if he is fully aware of the unacceptable clauses. In response to this problem, English law has employed both judicial and statutory intervention techniques to control unfair contract terms. This study describes and analyzes in detail how English law regulates such terms, particularly, in standard form, in order to provide legal advice to our sellers residing either in UK or in Korea who plan to enter into UK markets. It also attempts to explore any problem in the existing double legislations of UCTA and UTCCR and put forward future direction of English law in light of the Draft Unfair Terms Bill which was currently proposed by the Law Commissioners. The main concern of this paper will be confined to some of the various aspects of both judicial and statutory control of unfair contract terms in English law which may draw our attention in terms of domestic or international business sales.

  • PDF

Measurement of temperature profile in molter metal using a cod camera (ccd 카메라를 이용한 금속 용융면의 온도분포측정)

  • 노시표;정의창;임창환;김철중
    • Journal of the Korean Vacuum Society
    • /
    • v.12 no.1
    • /
    • pp.64-69
    • /
    • 2003
  • Using a high fewer electron beam gun (max. power 20 kW), Gadolinium (Gd, atomic number 64) metal was melted and the temperature distribution of melted surface was measured. With proper optical filters and the adjustment of aperture of lens, the radiation of melted surface was received by a ccd camera and its signal transferred to a computer. The real time monitoring of melted surface with a variation of electron beam Power was Possible and stable operation of electron beam was achieved. It was found that the max. temperature measured by a ccd camera with an assumption of blackbody radiation of melted Gd surface and adaption of Planet's law was above 100~$200^{\circ}C$ compared to that measured by a pyrometer in the same e-beam power.

A 3 Dimensional Characteristic Analysis of SLIM by the 2-D Finite Element Method (2차원 유한요소법에 의한 SLIM의 3차원적 특성 해석)

  • Cho, Yun-Hyun;Kim, Yong-Joo;Shin, Pan-Seok;Kang, Do-Hyun
    • Proceedings of the KIEE Conference
    • /
    • 1990.11a
    • /
    • pp.37-42
    • /
    • 1990
  • In order to obtain optimal design criteria and operating parameters, a Single-sided Linear Induction Motor (SLIM) is analysed by using a 2-D finite element method with magnetic and current vector potential. In the analysing procedures, the governing equation is derived from Maxwell's equation combined with the magnetic vector potential. As a forcing term, 3-phase voltage source is employed using the Kirchhoff's voltage law in order to look into effects of the unbalanced 3-phase currents and air gap flux density. Also, 2ndary eddy current distribution, longitudinal end and transverse edge effects are in turns visualized by flux lines in 3 different analysing planes as functions of frequency and input power.

  • PDF

MASS DISTRIBUTION IN THE CENTRAL FEW PARSECS OF THE MILKY WAY

  • Oh Seungkyung;Kim Sungsoo S.;Figer Donald F.;Morris Mark
    • Bulletin of the Korean Space Science Society
    • /
    • 2004.10b
    • /
    • pp.290-292
    • /
    • 2004
  • Near-IR observations of the central few parsecs of our Galaxy from the HST/NICMOS have been analyzed to produce H, K photometry. We have cross-identified our photometry with the Keck high-resolution spectrometry of the central 0.5 pc of our galaxy to distinguish evolved late-type stars from early-type stars, and use late-type stars as tracer population. We perform several statistical tests to find the best fitting parameters of stellar density distribution and velocity dispersion models, then derive volume number densities and velocity dispersions. The volume number density distribution has power law index $1.55\~1.7$. We then derive the mass distribution in the Central region of our Galaxy using the Jeans equation.

  • PDF

Static and Free Vibration Analysis of FGM Plates on Pasternak Elastic Foundation (Pasternak 탄성지반위에 놓인 점진기능재료 판의 정적 및 자유진동 해석)

  • Lee, Won-Hong;Han, Sung-Cheon;Park, Weon-Tae
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.29 no.6
    • /
    • pp.529-538
    • /
    • 2016
  • The simplified plate theory is presented for static and free vibration analysis of power-law(P) and sigmoid(S) Functionally Graded Materials(FGM) plates. This theory considers the parabolic distribution of the transverse shear stress, and satisfies the condition that requires the transverse shear stress to be zero on the upper and lower surfaces of the plate, without the shear correction factor. The simplified plate theory uses only four unknown variables and shares strong similarities with classical plate theory(CPT) in many aspects such as stress-resultant expressions, equation of motion and boundary conditions. The material properties of the plate are assumed to vary according to the power-law and sigmoid distributions of the volume fractions of the constituents. The Hamilton's principle is used to derive the equations of motion and Winkler-Pasternak elastic foundation model is employed. The results of static and dynamic responses for a simply supported FGM plate are calculated and a comparative analysis is carried out. The results of the comparative analysis with the solutions of references show relevant and accurate results for static and free vibration problems of FGM plates. Analytical solutions for the static and free vibration problems are presented so as to reveal the effects of the power law index, elastic foundation parameter, and side-to-thickness ratio.

Study on Barkhausen Avalanches in Fe Thin Film (Fe 박막에서의 박하우젠 현상 연구)

  • Lee, Hun-Sung;Ryu, Kwang-Su;Shin, Sung-Chul;Kang, Im-Seok
    • Journal of the Korean Magnetics Society
    • /
    • v.19 no.5
    • /
    • pp.176-179
    • /
    • 2009
  • We report a direct observation of Barkhausen avalanches in 50-nm Fe film, using a magneto-optical microscope magnetometer, capable of time-resolved domain observation. The time-resolved domain-evolution patterns exhibit that the occurrence of Barkhausen jump is random with respect to interval, size, and location. From the repetitive measurements more than 1000 times, we found that the probability distribution of Barkhausen jump size follows a power-law distribution and the critical exponent reveals the value of 1.14 $\pm$ 0.03.

Characteristics of Fracture Systems in Southern Korea (우리나라 단열구조의 특성)

  • 김천수;배대석;장태우
    • The Journal of Engineering Geology
    • /
    • v.13 no.2
    • /
    • pp.207-225
    • /
    • 2003
  • According to the data analysis of the regional fracture systems in southern Korea, the fracture orientations show three dominant sets : NNE, NW and WNW. A NNE set is the most abundant and includes most of the largest fractures. The highest fracture density is shown in the Taebaegsan mineralized area corresponding to Ogchon nonmetamorphic belt and the lowest one in the southwestern area of southern Korea. In addition, the density is higher in nonmetamorphic sedimentary rocks such as Choseon Supergroup. Pyeongan Supergroup, Daedong Supergroup and Kyeongsang Supergroup than in Precambrian basements and Jurassic granites. The regional fractures in southern Korea can be classified into four orders designated $F_1,{\;}F_2,{\;}F_3{\;}and{\;}F_4${\;}and{\;}F_4$ on the basis of their trace length. It is quite significant that fractures of each order are self-similar with respect to orientation and the combined fracture length distribution indicates a power-law distribution with an exponent of -2.04. As fractures were analyzed based on the tectonic provinces, Gyeonggj Massif and Kyeongsang Basin have all orders of fractures from $F_1$ to $F_4$. Most of the large scale faults may be ascribed to the products of slip accumulation through multiple deformation. Others besides $F_1$ fractures are thought to be evenly distributed through the whole area of southern Korea.