• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.467-469
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• 2000

This paper describes an application of discrete wavelet transform for power transformer protection. It is shown that the moving wavelet coefficients method based feature extraction for discrimination between actual internal faults and energizing state. The simulations of power transformer have been carried out using EMTP. The proposed method is more effectively and simpler to distinguish internal faults from inrush currents.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.1
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• pp.1-6
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• 2006

The emergence of competitive power market makes dispatch algorithm with transient stability constraints increasingly important for the transparent power system operation. Heuristic and off-line evaluation for the operation point can produce a discrimination among market players in the deregulated power system. In this paper, a dispatch algorithm with transient stability constraints is proposed. Energy margin under the TEF(Transient Energy Function) structure is adopted as a measure for the stability index. Implementation issues and simulation results are discussed in the context of a 10-bus system

• Journal of the Korean Statistical Society
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• v.22 no.2
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• pp.325-337
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• 1993

This paper propose two test statistics which enable us to proceed the variable selection in Fisher's linear discriminant function for the case of heterogeneous discrimination with equal training sample size. Simultaneous confidence intervals associated with the test are also given. These are exact and approximate results. The latter is based upon an approximation of a linear sum of Wishart distributions with unequal scale matrices. Using simulated sampling experiments, powers of the two tests have been tabulated, and power comparisons have been made between them.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.485-487
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• 2003

Independent Component Analysis (ICA) is used to generate ICA filter for computing feature vector for image window. Filters that have high discrimination power are selected to classify image from these ICA filters. Proposed classification algorithm is based on probability distribution of feature vector.

• Speech Sciences
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• v.1
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• pp.285-293
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• 1997

This paper was constructed to investigate strange attractor in considering speech which is regarded as chaos in that the random signal appears in the deterministic raising system. This paper searches for the delay time from AR model power spectrum for constructing fit attractor for speech signal. As a result of applying Taken's embedding theory to the delay time, an exact correlation dimension solution is obtained. As a result of this consideration of speech, it is found that it has more speaker recognition characteristic parameter, and gains a large speaker discrimination recognition rate.

• Proceedings of the KIEE Conference
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• 2000.11d
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• pp.663-665
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• 2000

For the control system of thermal turbine in fuel and nuclear power plant, as high reliability and availability are required, redundant control system is generally applied. This paper presents the configuration and design of such a redundant control system that can be suitable for control and monitoring of the turbine. System components such as I/O system, communication networks, voting system are designed, and especially the new intelligent voter using serial communication are proposed. The characteristics of the implemented control system is independence of the control, protection and monitoring functions, and discrimination of the redundancies, and high availability. The control functions such as speed control, load control, valve control and protective functions such as overspeed and PLU are designed in detail.

• Journal of Sasang Constitutional Medicine
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• v.5 no.1
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• pp.67-85
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• 1993

The Purpose of this study was to evaluate the reliability and the validation of four scales of Questionnaire for Sasang Constitution Classification (QSCC), newly constructed through statistical item analysis and to examine their diagnostic discrimination power. QSCC was administered to 105 inpatient at Kyung-Hee Oriental Medicine Hospital and local oriental clinics and 136 undergraduated students. 2 weeks later, QSCC was readministered to 220 same subjects. Data were collected during about 2 months from february to Apr. 20, 1992. For the purposes of this study, the collected data were analyzed by internal consistancy, test-retest reliability, ANOVA, Pearson correlation and discrimination analysis of spss pc+ v3.0 program. The results were as follows: 1. The reliability of four scales of QSCC was relatively favorable. The internal consistancy and test-retest reliability of Tae-Yaung-In(太陽人) scale were respectively Cronbach's ${\alpha}=0.9$ and r=0.89. Those of So-Yaung-In(少陽人) scale were respectively ${\alpha}=0.81$ and r=0.93. Those of Tae-Em-In(太陰人) scale were respectively ${\alpha}=0.72$ and r=0.74. Those of So-Em-In(少陰人) scale were respectively ${\alpha}=0.81$ and r=0.93. 2. The diagnostic discrimination abilities(Hit-ratio=56%)of QSCC were found to have more about 20% improvement than propotional chance criteria(37%). Especially, Hit-ratios for So-Yaung-In(63%) and Tae-Em-In(60%) were more high than that for So-Em-In(48%) 3. For male subjects, the construct validity of QSCC was founded to be relatively favorable. But that of QSCC for females was poor.

• Journal of Preventive Medicine and Public Health
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• v.46 no.2
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• pp.74-81
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• 2013

Objectives: The objective of this study was to evaluate the performance of risk-adjusted mortality models for colorectal cancer surgery. Methods: We investigated patients (n=652) who had undergone colorectal cancer surgery (colectomy, colectomy of the rectum and sigmoid colon, total colectomy, total proctectomy) at five teaching hospitals during 2008. Mortality was defined as 30-day or in-hospital surgical mortality. Risk-adjusted mortality models were constructed using claims data (basic model) with the addition of TNM staging (TNM model), physiological data (physiological model), surgical data (surgical model), or all clinical data (composite model). Multiple logistic regression analysis was performed to develop the risk-adjustment models. To compare the performance of the models, both c-statistics using Hanley-McNeil pair-wise testing and the ratio of the observed to the expected mortality within quartiles of mortality risk were evaluated to assess the abilities of discrimination and calibration. Results: The physiological model (c=0.92), surgical model (c=0.92), and composite model (c=0.93) displayed a similar improvement in discrimination, whereas the TNM model (c=0.87) displayed little improvement over the basic model (c=0.86). The discriminatory power of the models did not differ by the Hanley-McNeil test (p>0.05). Within each quartile of mortality, the composite and surgical models displayed an expected mortality ratio close to 1. Conclusions: The addition of clinical data to claims data efficiently enhances the performance of the risk-adjusted postoperative mortality models in colorectal cancer surgery. We recommended that the performance of models should be evaluated through both discrimination and calibration.

• Plant Journal
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• v.14 no.2
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• pp.45-50
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• 2018

Nuclear safety law's amendment caused many problems to use radiography testing(RT). Phased array ultrasonic testing(PAUT) was adapted instead of RT for NDE of welding points in boiler tubes these days. Unfortunately, PAUT doesn't give us the discrimination characteristics about flaws distinction and flaws size clearly. In this thesis, the distinction characteristics of flaw types and the detection characteristics of flaw size using PAUT of welding points in boiler tubes were analyzed. It was concluded that PAUT can distinguish between planar flaws and rounded flaws, but it is hard to tell apart the types of flaw respectively. We paid attention to the discrimination of flaws size because PAUT tends to underestimate the flaw size of porosity and underestimate or overestimate the flaw size of porosity.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.6
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• pp.41-49
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• 2017

Theoretical modelling and computational results for frequency coordination are presented over mobile base station and fixed wireless systems in urban or sub-urban area. Computational results with key parameters needed for interference analysis are performed and discussed in terms of system characteristics, propagation model, protection ratio, frequency dependent rejection, and discrimination angle with signal-interference plane. Based upon minimum coupling loss methodology, calculated interference powers of victim receiver for assumed system parameters are compared with maximum allowable interference power derived from protection ratio as functions of discrimination angle and distance including height-gain model in urban or sub-urban area. The proposed method is applicable for technical analysis on co-existence or interoperability for the various wireless systems, mandatory for frequency coordination or reallocation process.