• Title/Summary/Keyword: random points

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Visitors' Behavioral Characteristics and Attitudes to the Use and Managerial Attributes in Hallasan National Park, Korea (한라산국립공원에서의 탐방객 이용행태와 이용.관리속성에 대한 태도)

  • Yoo, Ki-Joon;Baek, Jae-Bong;Kim, Sun-Hee
    • Korean Journal of Environment and Ecology
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    • v.21 no.2
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    • pp.126-133
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    • 2007
  • This study was designed to provide basic visiter information for establishing effective park management strategies. A questionnaire survey was at major entry points in Hallasan National Park(Eorimok and Youngsil). 237 random samples among the visitors on the way back home from their visit were chosen to represent general visitor population. As for the results, visitors' recreational satisfaction level with the area was relatively high. The majority of the visitors were satisfied with 20 uses and management related attributes provided by Hallasan National Park system. However, considering lack of sense of hygienic sanitary facilities, consequential deterioration of natural and cultural resources, and entrance fees as well as other costs, there needs to be a managerial priority on visiter service.

MCMC Algorithm for Dirichlet Distribution over Gridded Simplex (그리드 단체 위의 디리슐레 분포에서 마르코프 연쇄 몬테 칼로 표집)

  • Sin, Bong-Kee
    • KIISE Transactions on Computing Practices
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    • v.21 no.1
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    • pp.94-99
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    • 2015
  • With the recent machine learning paradigm of using nonparametric Bayesian statistics and statistical inference based on random sampling, the Dirichlet distribution finds many uses in a variety of graphical models. It is a multivariate generalization of the gamma distribution and is defined on a continuous (K-1)-simplex. This paper presents a sampling method for a Dirichlet distribution for the problem of dividing an integer X into a sequence of K integers which sum to X. The target samples in our problem are all positive integer vectors when multiplied by a given X. They must be sampled from the correspondingly gridded simplex. In this paper we develop a Markov Chain Monte Carlo (MCMC) proposal distribution for the neighborhood grid points on the simplex and then present the complete algorithm based on the Metropolis-Hastings algorithm. The proposed algorithm can be used for the Markov model, HMM, and Semi-Markov model for accurate state-duration modeling. It can also be used for the Gamma-Dirichlet HMM to model q the global-local duration distributions.

Estimating Fatigue Life of APD Electronic Equipment for Activation of a Spaceborne X-band 2-axis Antenna (2축 짐벌식 X-band 안테나 구동용 전장품 APD 제어보드의 피로수명 평가)

  • Jeon, Young-Hyeon;Oh, Hyun-Ung
    • Journal of Aerospace System Engineering
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    • v.11 no.1
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    • pp.1-7
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    • 2017
  • While a satellite is carried into orbit by a launch vehicle, it is exposed to the severe launch environment with random vibrations and shock. Accordingly, these vibration sources affect electronic equipment, particularly the printed circuit board (PCB) in the satellite. When the launch load impacts the PCB, it causes negative behavior. This causes perpendicular bending around the boundary of fixation points that finally leads to the failure of solder joints, lead wires, and PCB cracks. To overcome these issues, the electronic equipment design must meet reliability requirements. In this paper, Steinberg's method is used to derive allowable and maximum deflection to verify design from a life perspective concerning the control board of the Antenna Pointing Driver (APD) mounted on KOMPSAT-3.

A Study of Asset and Risk Assessment for Established of Industrial Security Management System (산업보안 경영시스템 구축을 위한 자산 및 위험평가에 관한 연구)

  • Koh, Joon-Cheol;Kim, Tae-Soo;Joo, Yong-Ma;Kim, Woo-Hyun;Kang, Kyung-Sik
    • Journal of the Korea Safety Management & Science
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    • v.12 no.4
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    • pp.1-11
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    • 2010
  • The purpose of this study is, by recognizing that recently, as crimes using information and various adverse-effect phenomena such as hacking and virus occur frequently with rapid development of information network such as Internet in every field of industry, the range of security is widening to the field of industrial areas for preventing the leaking of industrial technology and protecting that technology as well as information security only limited to IT area, and by establishing common concept about industrial security through education on the industrial security at the point of increasing importance of industrial security, to prepare the base of comprehensive risk management system for protecting company's assets (physical factor, technical factor and managerial factor) safely from the random threats or attacks inside and outside the company through assessment of important assets of the company, evaluation of threats and weak points, and risk assessment by building industrial security management system in order to protect company's information assets and resources which are connected to the existence of the company safely from the threats or attacks from inside or outside the company and to spread stable business activities.

A Study on Cervical Curvature and Thermography in Some Neck Pain Patients (경항통 환자의 경추 만곡도와 체표열에 대한 연구)

  • Yang, Jae-Sun;Lee, Sang-Gyu;Lee, Chong-woo;Yeom, Seung-Ryong;Kwon, Young-Dal;Lee, Soo-Kyung;Song, Yong-Sun
    • Journal of Korean Medicine Rehabilitation
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    • v.15 no.2
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    • pp.105-105
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    • 2005
  • Objectives : The purpose of this study was to investigate the correlation between cervical spine curvature and thermography on neck pain patients. Methods : The cervical spine curvature was assessed on lateral view of plain radiograph by three measurements(Depth of cervical curve, Method of Jochumsen, Angle of cervical curve), then the neck pain patients were divided into straight curvature group(Straight group), normal curvature group(Control I), and no neck pain group(Control II) was selected by random sampling. I measured temperature of the both side Pungji(風池, G20), Kyonjong(肩井, G21), Chonjong(天宗, SI11) by thermography examination on Experimental group(Straight group) and control group(Control I, II), then analyzed the temperature statically with student's t-test, ANOVA. Results : The temperature of six point on Straigt group was lower than that of Control I, but had no significant difference(p>0.05). The temperature of six point on Straigt group was lower than that of Control II. The descent of temperature on Lt. Pungji(風池, G20), Lt. Kyonjong(肩井, G21), Rt. Chonjong(天宗, SI11) had significance(p<0.05). There is no corelation between onset period and mean temperature of six points. Conclusions : Thermography represnets the presence of neck pain, but has no correlation with straight of cervical curvature.

Free-Form Surface Reconstruction Method from Second-Derivative Data (형상이차미분을 이용한 자유곡면 형상복원법)

  • Kim, Byoung Chang;Kim, DaeWook;Kim, GeonHee
    • Korean Journal of Optics and Photonics
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    • v.25 no.5
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    • pp.273-278
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    • 2014
  • We present an algorithm for surface reconstruction from the second-derivative data for free-form aspherics, which uses a subaperture scanning system that measures the local surface profile and determines the three second-derivative values at those local sampling points across the free-form surface. The three second-derivative data were integrated to get a map of x- and y-slopes, which went through a second Southwell integration step to reconstruct the surface profile. A synthetic free-form surface 200 mm in diameter was simulated. The simulation results show that the reconstruction error is 19 nm RMS residual difference. Finally, the sensitivity to noise is diagnosed for second-derivative Gaussian random noise with a signal to noise ratio (SNR) of 16, the simulation results proving that the suggested method is robust to noise.

A Study on the Socio-economic Characteristics of the Angler Population and the Estimation of A Fishing Frequency Function (유어낚시인구의 사회경제학적 특성과 출조빈도함수의 추정에 관한 연구)

  • Park Cheol-Hyung
    • The Journal of Fisheries Business Administration
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    • v.36 no.1 s.67
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    • pp.81-101
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    • 2005
  • This article is to estimate the fishing frequency function in Korean recreational fishery with respect to socio-economic characteristics of anglers. First, the study described the characteristics of the entire angler population on the view points of 9 socio-economic variables. And then, the study divided the total angler population into three groups of in-land, sea, and mixed angler populations in order to investigate the differences in their characteristics. The study could confirm the existence of differences in regions, size of regions, and educational levels between the in - land and the sea angler populations by testing heterogeneity in the frequency table. The fishing frequency function is estimated using Poisson regression model in order to accomodate the count data(non-negative discrete random variable) aspects of the fishing frequency. However, the model specification error is found due to overdispersion of data. The model exhibits the lack of goodness of fit. The negative binomial regression model is adopted to cure the overdispersion of the data as an alternative estimation methodology. Finally, the study can confirm overdispersion does not exist in the model any more and the goodness of fit improved significantly to the reasonable level. The results of estimation of fishing frequency population modeled by the negative binomial regression models are following. The three variables of region, sex, and education have effects on the decision making process of fishing frequency in the case of in-land recreation fishery. On the other hand, the three variables of sex, age, and marriage status do the same job in the case of sea angler population. Among the left-over variables, both income and use of Internet variables now affect on the process in mixed angler population. Finally, the results of whole angler population show that all of the previous variables are proven to be statistically significant due to the summation of data with all three sub-groups of angler population.

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A Survey on Health Promoting Behavior and its Related Factors for High School Students (고등학생의 건강증진행위와 관련요인 분석)

  • Mun, Young-Hee
    • Research in Community and Public Health Nursing
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    • v.12 no.1
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    • pp.81-91
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    • 2001
  • In order to identify the health promoting behavior and its related factors for high school students, a survey was performed from 4th to 8th of December 2000. Population were selected by stratified random sampling method and total 355 students replied to the self-administered questionnaire survey. Data analysis was done by descriptive statistics, t-test, ANOVA. Pearson's Correlation, stepwise multiple regression. The results were as follows: 1. The average score of health promoting behavior practices was 2.23(SD=.41) points by the 4 point scale, which was lower than that of adults. In the subcategories, the highest degree of performance was self-actualization (mean= 2.68, SD=.68), and the lowest degree was health responsibility (mean = 1.33, SD= .41). 2. According to gender(t=2.70, p=.00), school type(t=2.53, p=.01), father's educational level(F=4.16, p=.00), sleeping hours(F=3.80, p = .02), and number of hours at school (F=4.44, p=.01), there were a statistically significant differences in modifying factors. of health promoting behavior. 3. Health promoting behavior showed significant positive correlations with self- efficacy(r= .461. p= .000), internal health locus of control (r=.284, p=.000), perceived health status (r=.163, p=.002). 4. The combination of self-efficacy, internal health locus of control. school type, and gender explained 30% of the variance of health promoting behavior. Therefore, the findings of research can serve as the basis for developing health promoting programs, which enhance self-efficacy and performed in school and community.

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A Study on the Minimum Error Entropy - related Criteria for Blind Equalization (블라인드 등화를 위한 최소 에러 엔트로피 성능기준들에 관한 연구)

  • Kim, Namyong;Kwon, Kihyun
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.2 no.3
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    • pp.87-95
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    • 2009
  • As information theoretic learning techniques, error entropy minimization criterion (MEE) and maximum cross correntropy criterion (MCC) have been studied in depth for supervised learning. MEE criterion leads to maximization of information potential and MCC criterion leads to maximization of cross correlation between output and input random processes. The weighted combination scheme of these two criteria, namely, minimization of Error Entropy with Fiducial points (MEEF) has been introduced and developed by many researchers. As an approach to unsupervised, blind channel equalization, we investigate the possibility of applying constant modulus error (CME) to MEE criterion and some problems of the method. Also we study on the application of CME to MEEF for blind equalization and find out that MEE-CME loses the information of the constant modulus. This leads MEE-CME and MEEF-CME not to converge or to converge slower than other algorithms dependent on the constant modulus.

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Machine Learning Perspective Gene Optimization for Efficient Induction Machine Design

  • Selvam, Ponmurugan Panneer;Narayanan, Rengarajan
    • Journal of Electrical Engineering and Technology
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    • v.13 no.3
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    • pp.1202-1211
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    • 2018
  • In this paper, induction machine operation efficiency and torque is improved using Machine Learning based Gene Optimization (ML-GO) Technique is introduced. Optimized Genetic Algorithm (OGA) is used to select the optimal induction machine data. In OGA, selection, crossover and mutation process is carried out to find the optimal electrical machine data for induction machine design. Initially, many number of induction machine data are given as input for OGA. Then, fitness value is calculated for all induction machine data to find whether the criterion is satisfied or not through fitness function (i.e., objective function such as starting to full load torque ratio, rotor current, power factor and maximum flux density of stator and rotor teeth). When the criterion is not satisfied, annealed selection approach in OGA is used to move the selection criteria from exploration to exploitation to attain the optimal solution (i.e., efficient machine data). After the selection process, two point crossovers is carried out to select two crossover points within a chromosomes (i.e., design variables) and then swaps two parent's chromosomes for producing two new offspring. Finally, Adaptive Levy Mutation is used in OGA to select any value in random manner and gets mutated to obtain the optimal value. This process gets iterated till finding the optimal value for induction machine design. Experimental evaluation of ML-GO technique is carried out with performance metrics such as torque, rotor current, induction machine operation efficiency and rotor power factor compared to the state-of-the-art works.