• Journal of information and communication convergence engineering
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• 제5권3호
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• pp.245-248
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• 2007

In this paper, we research the content-based analysis and classification according to the composition of the feature parameter data base for the audio data to implement the audio data index and searching system. Audio data is classified to the primitive various auditory types. We described the analysis and feature extraction method for the feature parameters available to the audio data classification. And we compose the feature parameters data base in the index group unit, then compare and analyze the audio data centering the including level around and index criterion into the audio categories. Based on this result, we compose feature vectors of audio data according to the classification categories, and simulate to classify using discrimination function.

• 대한핵의학회지
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• 제1권2호
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• pp.75-84
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• 1967

$^{131}I$-labeled-O-iodohippurate renograms in 15 cases of epidemic hemorrhagic fever(E.H. fever)during oliguric, diuretic and convalescent phase were analysed quantitatively and qualitatively, namely by its configuration, Tmax T 1/2 and renal index of Hirakawa. The results were as following: 1) Changes on the renograms in E.H. fever showed simultaneous bilateral renal impairment. 2) The characteristic configurations of renogram in the oliguric phase were: (1) Moderately decreased absolute amplitude of initial spike. (2) Continous rising second slope. (3) No appearance of terminal descent. Those were mast likely to those of renograms in acute ureteral obstruction or acute dehydration state. 3) During the diuretic phase, the renogram showed the point of maximal amplitude, but the steepness of 2nd slope was markedly decreased. The appearance of terminal descents was observed with unusually high amplitude despite of the tremendously large amount of urinary output during this phase. 4) In convalescence, the renograms were essentially normal in configuration, but the renal index of Hirakawa was not recovered until this phase. 5) Renograms in E.H. fever showed the characteristic patterns in each phase of its clinical course. 6) $^{131}I$-OIH-Renogram might be an useful method for the evaluation of renal function in E.H. fever during its course.

• 한국화재소방학회논문지
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• 제25권3호
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• pp.14-19
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• 2011

본 연구는 방화와 관련하여 방화저감에 목표를 가지고, 사회적 현상과의 관계를 밝히는 것에 중점을 가지고 연구가 실시되었다. 특히 기존의 연구와 달리 방화의 동기 중, 경제적인 동기에 주목하여 경제적지표가 방화에 어떤 영향을 미치는가에 대한 탐색적 연구를 실시하였다. 분석결과, 방화와 관련된 경제적 현상에 대한 관계를 밝혔다. 구체적인 내용으로 경제성장율, 소비자물가지수가 감소하면 전체적인 경기가 좋지 않아 방화건수가 늘어났다. 역으로 경제성장율, 소비자물가지수가 증가하면 방화건수가 감소하였다. 그리고 개인채무비율이 증가하면 방화건수도 증가하는 현상에 대해 밝혔다.

• 한국농공학회논문집
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• 제55권6호
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• pp.77-85
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• 2013

The efficient operation and management strategies of reservoirs in irrigation periods of drought events are an essential element for drought planning and countermeasure. Korea Rural Community Corporation has developed the real-time water level observation system of agricultural reservoirs to efficiently operate reservoirs, however, it is not possible to predict drought conditions, and only provides information of current situation. Hence, it is necessary to evaluate accurate irrigation vulnerability and efficiently reservoir operation rules using current water level. In this paper, the improvement methods of reservoir operation planning were developed with water supply vulnerability characteristic curves comparing to automatic water gauge at agricultural reservoirs. The 11 reservoirs were simulated applying the reservoir operation rules which was determined by irrigation vulnerability characteristic curves criteria and real time water level, and evaluated water supply situation in 2012 year. The analysis of results can be identified probabilistic possibility of water supply failures compared with the existing reservoir operation criteria. These results of efficient reservoir operation rules can be achieved enable irrigation planners to optimally manage available water resources for decision making, and contributed to maintain the water supply according to demand strategy for agricultural reservoirs management.

• 한국임상수의학회지
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• 제33권2호
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• pp.97-101
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• 2016

In the field of clinical medicine, diagnostic accuracy studies refer to the degree of agreement between the index test and the reference standard for the discriminatory ability to identify a target disorder of interest in a patient. The receiver operating characteristic (ROC) curve offers a graphical display the trade-off between sensitivity and specificity at each cutoff for a diagnostic test and is useful in assigning the best cutoff for clinical use. In this end, the ROC curve analysis is a useful tool for estimating and comparing the accuracy of competing diagnostic tests. This paper reviews briefly the measures of diagnostic accuracy such as sensitivity, specificity, and area under the ROC curve (AUC) that is a summary measure for diagnostic accuracy across the spectrum of test results. In addition, the methods of creating an ROC curve in single diagnostic test with five-category discrete scale for disease classification from healthy individuals, meaningful interpretation of the AUC, and the applications of ROC methodology in clinical medicine to determine the optimal cutoff values have been discussed using a hypothetical example as an illustration.

• 대한방사선기술학회지:방사선기술과학
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• 제46권5호
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• pp.367-377
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• 2023

This study investigates the utility of the Triglyceride-glucose(TyG) index and Cardiometabolic Index(CMI) as predictors for diagnosing metabolic syndrome. The study involved 1970 males, 1459 females, totaling 3429 participants who underwent health checkups at P Hospital in Busan between January 2023 and June 2023. Metabolic syndrome diagnosis was based on the presence of 3 or more risk factors out of the 5 criteria outlined by the American Heart Association/National Heart, Lung, and Blood Institute(AHA/NHLBI), and participants with 2 or fewer risk factors were categorized as normal. Statistical analyses included independent sample t-tests, chi-square tests, Pearson's correlation analysis, Receiver Operating Characteristic(ROC) curve analysis, and logistic regression analysis, using the Statistical Package for the Social Sciences(SPSS) program. Significance was established at p<0.05. The comparison revealed that the metabolic syndrome group exhibited attributes such as advanced age, male gender, elevated systolic and diastolic blood pressures, high blood sugar, elevated triglycerides, reduced LDL-C, elevated HDL-C, higher Cardiometabolic Index, Triglyceride-glucose index, and components linked to abdominal obesity. Pearson correlation analysis showed strong positive correlations between waist circumference/height ratio, waist circumference, Cardiometabolic Index, and triglycerides. Weak positive correlations were observed between LDL-C, body mass index, and Cardiometabolic index, while a strong negative correlation was found between Cardiometabolic Index and HDL-C. ROC analysis indicated that the Cardiometabolic Index(CMI), Triglyceride-glucose(TyG) index, and waist circumference demonstrated the highest Area Under the Curve(AUC) values, indicating their efficacy in diagnosing metabolic syndrome. Optimal cut-off values were determined as >1.34, >8.86, and >84.5 for the Cardiometabolic Index, Triglyceride-glucose index, and waist circumference, respectively. Logistic regression analysis revealed significant differences for age(p=0.037), waist circumference(p<0.001), systolic blood pressure(p<0.001), triglycerides(p<0.001), LDL-C(p=0.028), fasting blood sugar(p<0.001), Cardiometabolic Index(p<0.001), and Triglyceride-glucose index (p<0.001). The odds ratios for these variables were 1.015, 1.179, 1.090, 3.03, and 69.16, respectively. In conclusion, the Cardiometabolic Index and Triglyceride-glucose index are robust predictive indicators closely associated with metabolic syndrome diagnosis, and waist circumference is identified as an excellent predictor. Integrating these variables into clinical practice holds the potential for enhancing early diagnosis and prevention of metabolic syndrome.

• 한국결정성장학회지
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• 제2권2호
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• pp.40-52
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• 1992

Titanium-iso-propoxide[$Ti(OC_3H_7)_4$]와 Tetra-ethyl-lead $[Pb({C_2}{H_5})_4]$를 사용한 MOCVD법으로 PbTi$O_3$박막을 55$0^{\circ}C$에서 증착하였다. Ar과 $O_2$를 각각 운반 및 반응기체로 사용하였으며, 열처리에 따른 박막의 두께와 굴절지수의 변화, Xtjs 회절 분석, CV 특성 측정등을 행하였다. 열처리에 따른 CV 특성 측정 결과 PbTi$O_3$는 Si기판과 계면 반응을 하는 것으로 생각되며, X선 회절 분석 결과 $PbTiO_3$의 특성 peak들이 관찰되었다. 열처리 시간 및 온도의 증가에 따라 박막의 두께는 감소하고, 굴절지수는 증가하는 경향을 보여 주었다.

• 한국정보통신학회논문지
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• 제21권11호
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• pp.2191-2198
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• 2017

군 무기체계의 성능을 점검하기 위해 사용되는 정밀측정장비는 수명주기 동안 측정신뢰도 유지를 위해 주기적으로 교정된다. 기존의 교정주기 관련 연구들은 장비의 샘플 크기와 특성을 고려하여 측정신뢰도 모델을 결정할 것을 제안하고 있으나, 다양한 정밀측정장비의 정비 데이터에 동일한 특성 분포를 가정하고 단일 모델을 적용하는 것은 적합하지 않을 수 있다. 본 논문에서는 정밀측정장비의 수명주기 동안 욕조 곡선의 특성을 가정하여 측정신뢰도 모델들로부터 추정된 교정주기 가운데 F-검정과 성능지수 평가를 통해 정비 데이터에 가장 적합한 교정주기가 선택되도록 제안하였다. 제안한 방법을 다양한 장비에 적용한 결과 교정주기 동안 장비의 신뢰도가 유지됨을 확인하였다.

• 동력기계공학회지
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• 제20권6호
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• pp.27-33
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• 2016

BLDC motors have the strong point of allowing high-efficiency operation, yet with the weak point of requiring position information for operation. Moreover, there have recently been frequent cases where the product differentiation of even a cheap BLDC motor demanded a high level of control performance similar to that of a controller using a high-precision position sensor. This paper proposes low cost position sensor that enables the acquisition of rotor position information based on index and incremental PWM, using a single position sensor instead of an expensive incremental encoder or a cheap 3 phase hall sensor. The characteristic of the proposed encoder is that index information at every $60^{\circ}$ of electrical angle is inscribed on the encoder disk, as well as a multiple number of values representing information about PWM, which is obtained by modulating information about the electrical angle of the rotor that has the resolution of $60^{\circ}$. Such a method has the characteristic of enabling the acquisition of high-precision position information based on the information about a multiple number of PWM waveforms and counter values that have all been inscribed on the encoder disk for each $60^{\circ}$ range. The feasibility of the proposed new encoder was verified by fabricating a prototype encoder generating 240 pulses, followed by confirming its performance using Micom's capture and software counter functions.

• Geomechanics and Engineering
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• 제29권4호
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• pp.377-390
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• 2022

The stability of the roof rock-coal pillar-floor rock composite structure is of great significance to coal mine safety production. The cracks existing in the composite structure seriously affect the stability of the roof rock-coal pillar-floor rock composite structure. The numerical simulation tests of rock-coal-rock composite structures with different crack characteristics were carried out to reveal the composite structures' mechanical properties and failure mechanisms. The test results show that the rock-coal-rock composite structure's peak stress and elastic modulus are directly proportional to the crack angle and inversely proportional to the crack length. The smaller the crack angle, the more branch cracks produced near the main control crack in the rock-coal-rock composite structure, and the larger the angle between the main control crack and the crack. The smaller the crack length, the larger the width of the crack zone. The impact energy index of the rock-coal-rock composite structure decreases first and then increases with the increase of crack length and increases with the increase of crack angle. The functional relationships between the different crack characteristics, peak stress, and impact energy index are determined based on the sensitivity analysis. The determination of the functional relationship can fully grasp the influence of the crack angle and the crack length on the peak stress and impact energy index of the coal-rock composite structure. The research results can provide a theoretical basis and guidance for preventing the instability and failure of the coal pillar-roof composite structure.