• Korean Journal of Remote Sensing
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• v.25 no.3
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• pp.271-285
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• 2009

Multi-temporal satellite imagery can be changed into a transform image that emphasizes the changed area only through the application of various change detection techniques. From the transform image, an automated change detection model calculates the optimal threshold value for classifying the changed and unchanged areas. However, the model can cause undesirable results when the histogram of the transform image is unbalanced. This is because the model uses a single threshold value in which the sign is either positive or negative and its value is constant (e.g. -1, 1), regardless of the imbalance between changed pixels. This paper proposes an advanced method that can improve accuracy by applying separate threshold values according to the increased or decreased range of the changed pixels. It applies multiple threshold values based on the cumulative producer's and user's accuracies in the automated binary change detection model, and the analyst can automatically extract more accurate optimal threshold values. Multi-temporal IKONOS satellite imagery for the Daejeon area was used to test the proposed method. A total of 16 transformation results were applied to the two study sites, and optimal threshold values were determined using accuracy assessment curves. The experiment showed that the accuracy of most transform images is improved by applying multiple threshold values. The proposed method is expected to be used in various study fields, such as detection of illegal urban building, detection of the damaged area in a disaster, etc.

• Communications for Statistical Applications and Methods
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• v.12 no.2
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• pp.313-322
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• 2005

In this paper, we discuss suppression for logistic regression model. Suppression for linear regression model was defined as the relationship among sums of squared for regression as well as correlation coefficients of. variables. Since it is not common to obtain simple correlation coefficient for binary response variable of logistic model, we consider cumulative logistic models with multinomial and ordinal response variables rather than usual logistic model. As number of category of a response variable for the cumulative logistic model gets collapsed into binary, it is found that suppressions for these logistic models are changed. These suppression results for cumulative logistic models are discussed and compared with those of linear model.

• Proceedings of the Korean Statistical Society Conference
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• 2003.05a
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• pp.79-84
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• 2003

Likelihood estimation in random-effect models is often complicated because the marginal likelihood involves an analytically intractable integral. Numerical integration such as Gauss-Hermite quadrature is an option, but is generally not recommended when the dimensionality of the integral is high. An alternative is the use of hierarchical likelihood, which avoids such burdensome numerical integration. These two approaches for fitting binary data are compared and the advantages of using the hierarchical likelihood are discussed. Random-effect models for binary outcomes and for bivariate binary-continuous outcomes are considered.

• Journal of Astronomy and Space Sciences
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• v.33 no.4
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• pp.257-264
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• 2016

A planet revolving around binary star system is a familiar system. Studies of these systems are important because they provide precise knowledge of planet formation and orbit evolution. In this study, a method to determine the evolution of an exoplanet revolving around a binary star system using different rates of stellar mass loss will be introduced. Using a hierarchical triple body system, in which the outer body can be moved with the center of mass of the inner binary star as a two-body problem, the long period evolution of the exoplanet orbit is determined depending on a Hamiltonian formulation. The model is simulated by numerical integrations of the Hamiltonian equations for the system over a long time. As a conclusion, the behavior of the planet orbital elements is quite affected by the rate of the mass loss from the accompanying binary star.

• 한국정보통신설비학회:학술대회논문집
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• 2008.08a
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• pp.429-432
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• 2008

In this paper, performance of a double binary turbo coded ultra wide band (UWB) system is analyzed and simulated in an indoor wireless channel. Binary pulse position modulation-time hopping (BPPM-TH) signals are considered. The indoor wireless channel is modeled as a modified Saleh and Valenzuela (SV) channel. The performance is evaluated in terms of bit error probability (BER). From the simulation results, it is seen that double binary turbo coding offers considerable coding gain with reasonable encoding complexity. It is also demonstrated that the performance of the UWB system can be substantially improved by increasing the number of iterations.

• Journal of Multimedia Information System
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• v.5 no.4
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• pp.273-276
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• 2018

In video compression standards, the entropy coding is essential to the high performance compression because redundancy of data symbols is removed. Binary arithmetic coding is one of high performance entropy coding methods. However, the dependency between consecutive binary symbols prevents improving the throughput. For the throughput enhancement, a new probability model is proposed for encoding multi-symbols at one time. In the proposed method, multi-symbol encoder is implemented with only adders and shifters, and the multiplication table for interval subdivision of binary arithmetic coding is removed. Compared to the compression ratio of CABAC of H.264/AVC, the performance degradation on average is only 1.4% which is negligible.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.52.1-52.1
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• 2021

Low mass X-ray binary(LMXB) 중 accretion disk가 존재하지 않으며 매우 작은 질량 (1 ≪ M_⊙)의 동반성을 가지는 pulsar binary system에서 중성자별과 동반성의 항성풍은 상호작용하여 intrabinary shock(IBS)을 형성한다. 이곳에서 입자들은 상대론적으로 가속되어 싱크로트론 복사를 방출한다고 생각된다. 이 복사는 X-선 영역으로 관측되며 이때 관측된 X-선 궤도 광도곡선은 IBS의 모양에 따라 달라진다. 우리는 IBS의 X-선 복사 과정을 모델화하여 shock의 모양과 내부의 전자 특성을 파악하고, 광학 관측을 통해 얻은 orbital parameter와 비교하며 binary의 geometry를 보다 정확히 이해하고자 한다. 이 발표에서는 다양한 pulsar binary system의 Chandra, XMM 그리고 NuSTAR의 X-선 관측 데이터에 IBS 모델을 적용해보고 IBS와 binary의 geomerty를 분석한 결과를 제시한다.

• Communications for Statistical Applications and Methods
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• v.10 no.3
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• pp.909-917
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• 2003

Although many classification models have been used to classify binary data, none of the classification models dominates all varying circumstances depending on the number of variables and the size of data(Asparoukhov and Krzanowski (2001)). This paper proposes a classification model which uses information on marginal distributions of sub-variables and its maximum entropy distribution. Classification experiments by using simulation are discussed.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.11-14
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• 1998

This paper introuces a new efficient method of synchronization acquisition which is the most important element in DS-CDMA system using the phase offset of binary code. This approach uses the binary code function which can easily estimate the phase offset from the received spreading waveforms which respect to the receiver-stored replica of the spreading code. This paper proposes the initial acquisition model with repeat error control device that is good for perfomance. The hardware is implemented by TMS320c30

• Journal of the Korean Statistical Society
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• v.34 no.1
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• pp.61-71
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• 2005

A class of asymmetric ARCH processes is proposed via binary random power transformations. This class accommodates traditional nonlinear models such as threshold ARCH (Rabemanjara and Zacoian (1993)) and Box-Cox type ARCH models(Higgins and Bera (1992)). Stationarity condition of the model is addressed. Iterative least squares(ILS) and pseudo maximum like-lihood(PML) methods are discussed for estimating parameters and related algorithms are presented. Illustrative analysis for Korea Stock Prices Index (KOSPI) data is conducted.