• The Korean Journal of Applied Statistics
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• v.28 no.6
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• pp.1121-1131
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• 2015

Logistic models with a random intercept are useful to analyze longitudinal binary data. Traditionally, the random intercept of the logistic model is assumed to be parametric (such as normal distribution) and is also assumed to be independent to variables. Such assumptions are very strong and restricted for application to real data. Recently, Garcia and Ma (2015) derived semiparametric efficient estimators for logistic model with a random intercept without these assumptions. Their estimator shows the consistency where we do not assume any parametric form for the random intercept. In addition, the method is computationally simple. In this paper, we apply this method to analyze toenail infection data. We compare the semiparametric estimator with maximum likelihood estimator, penalized quasi-likelihood estimator and hierarchical generalized linear estimator.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.3
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• pp.310-318
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• 1983

Four methods of vegetation analysis were compared to determine the most suitable method to use in transplanted rice. The highest number of weed species, 14 was obtained with the list quadrat method while the least number, 8 was obtained with the line intercept method. The clip quadrat method tended to overestimate weed species with a low moisture content such as Sagittaria trifolia L. and Ludwigia prostrata Roxb while for the list quadrat method, weed species with a high moisture content such as Sagittaria pygmaea Miq. and Monochoria vaginalis (Burm. f) Pres 1 were overestimated. With the line intercept method, weed species having conspicuous leaf blades such as S. trifolia and Potamogeton distinctus Benn. were dominant. Of the methods tested, the line intercept method was the least desirable because it accounted for the least number of weed species. Any of the others could be use for vegetation analysis without any significant problems arising. However, preference was given to the point quadrat method because of the ease of measurement. It was also less tedious and less time consuming than the other methods.

• Journal of the Korea Society for Simulation
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• v.29 no.2
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• pp.49-61
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• 2020

It is important to operate a limited number of interceptors effectively to counter ballistic missile threats. The existing interceptor operating method determines the number of interceptors according to the level of TBM (Theater Ballistic Missile) engagement effectiveness applied to a defended asset. It can cause either excessive interceptor waste compared to the intercept probability or the intercept probability decrease. Thus, interceptor operating method must be decided considering the number of ballistic missiles, intercept probability and cost. This study proposes a mathematical model to improve the existing interceptor operating method. In addition, the efficiency indicator is proposed for trade-off between intercept probability and cost. As a result of the simulations, the mathematical model-based interceptor operating method can achieve better results than the existing interceptor operating method.

• Journal of the Institute of Convergence Signal Processing
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• v.22 no.4
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• pp.213-219
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• 2021

The submarine's intercept pulse detection detects pulses radiated from enemy surface ships, submarines, and torpedoes, and performs an important function of providing maneuverability and survivability of submarine. Whether or not the intercept pulse is detected is determined by comparing the size of the received pulse with the threshold value by the operator. In the case of intercept pulses, the intensity of the pulses is frequently reduced under the influence of various environmental factors. In the situation, if detection is performed with a fixed threshold, a non-detection problem occurs and persists until the operator sets a low threshold. In this paper, we proposed method for automatically adjusting threshold to reduce the non-detection problem caused by a fixed threshold. Simulation were preformed on 4 cases with different pulse level fluctuation widths, and it was confirmed that the detection performance was improved by increasing the number of detections when a method for automatically adjusting threshold was applied to all cases. Through the proposed method, it is expected that the intercept pulse detection performance will be improved in the marine environment the large fluctuations in pulse level in the future.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.344-345
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• 2006

The linear intercept (LI) method was used to quantitatively measure the intercepts of WC grains in nano-grained WC-10Co hardmetal. When the surveyed intercept numbers of WC grain exceeded 200, the statistic data for the mean grain size of WC were reproduced. The discriminative minimal grain size of used LI method was 12 nm; the maximum intercept of WC grain was 109 nm; the average intercept of WC grains was 45 nm and the corresponding 3D mean grain size of WC was 70 nm which is agreeable with the XRD outcome.

• International Journal of Aeronautical and Space Sciences
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• v.11 no.2
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• pp.118-125
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• 2010

This paper describes a mid-course guidance strategy based on the earliest intercept geometry (EIG) guidance. An analytical solution and performance validation will be addressed for generalized mid-course guidance problems in area air-defence in order to improve reachability and performance. The EIG is generated for a wide range of possible manoeuvres of the challenging missile based on the guidance algorithm using differential geometry concepts. The main idea is that a mid-course guidance law can defend the area as long as it assures that the depending area and objects are always within the defended area defined by EIG. The velocity of Intercept Point in EIG is analytically derived to control the Intercept Geometry and the defended area. The proposed method can be applied in deciding a missile launch window and launch point for the launch phase.

• Journal of the Korean Society of Safety
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• v.23 no.6
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• pp.164-170
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• 2008

This research was verified detection way of intercept vehicles and performance evaluation after system installation using image detector as detection way of ground installation. By image recognition algorithm was on the trace of moving orbit of violation vehicles for detection way of intercept vehicles. When moving orbit is located special site, utilized geometric image calibration and DC-notch filter. These are cognitive system of license plate by making signal. Then, Bright Evidence Detection and Dark Evidence Detection were applied to after mixing. It is applied to way of Backward tracking for detection way of intercept vehicles. After the field evaluation of developed system, it should be analyzed the more high than recognition rate of minimum standards 80%. It should rise in the estimation of the site applicability is highly from now.

• Journal of the Korean Data and Information Science Society
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• v.25 no.2
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• pp.411-422
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• 2014

This study analyzed how average GPA (grade point average) changes as the number of completed semesters increases based on the estimates of intercept, slope, and quadratic term. The students included in this study are those who was admitted in 2011 and took 6 consecutive semesters. More precisely, it was analyzed if intercept, slope and quadratic term of average GPA were different between gender and selection method. The results showed that the intercept was different between selection method, the slope was different between gender, but the quadratic term was different between neither selection method nor gender.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.11
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• pp.902-910
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• 2018

This paper deals with spacecraft intercept problem on non-coplanar elliptical obit considering J2 perturbation. This disturbance addressed in this work is a major factor changing the trajectory of a spacecraft orbiting the Earth. To resolve this issue, a real-time intercept method is proposed. This method is based on the optimization problem which consist of the equation of motion considering spherical earth and impulse, and the optimal solution numerically obtained is set as the direction of the thrust of the interceptor. The position error is resolved by iteratively solving the optimization problem and modifying the direction of thrust of interceptor. The proposed method in this paper is verified by using various numerical examples.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.4
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• pp.729-739
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• 2017

The objective of this study was to optimize minimum-energy impulsive spacecraft intercept using genetic algorithms. A mathematical model was established on two-body system based on f and g solution and universal variable to address spacecraft intercept problem for non-coplanar elliptical orbits. This nonlinear problem includes many local optima due to discontinuity and strong nonlinearity. In addition, since it does not provide a closed-form solution, it must be solved using a numerical method. Therefore, the initial guess is that a very sensitive factor is needed to obtain globally optimal values. Genetic algorithms are effective for solving these kinds of optimization problems due to inherent properties of random search algorithms. The main goal of this paper was to find minimum energy solution for orbit transfer problem. The numerical solution using initial values evaluated by the genetic algorithm matched with results of Hohmann transfer. Such optimal solution for unrestricted arbitrary elliptic orbits using universal variables provides flexibility to solve orbit transfer problems.