• Title/Summary/Keyword: operating characteristic

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A Novel System for Detecting Adult Images on the Internet

  • Park, Jae-Yong;Park, Sang-Sung;Shin, Young-Geun;Jang, Dong-Sik
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.4 no.5
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    • pp.910-924
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    • 2010
  • As Internet usage has increased, the risk of adolescents being exposed to adult content and harmful information on the Internet has also risen. To help prevent adolescents accessing this content, a novel detection method for adult images is proposed. The proposed method involves three steps. First, the Image Of Interest (IOI) is extracted from the image background. Second, the IOI is distinguished from the segmented image using a novel weighting mask, and it is determined to be acceptable or unacceptable. Finally, the features (color and texture) of the IOI or original image are compared to a critical value; if they exceed that value then the image is deemed to be an adult image. A Receiver Operating Characteristic (ROC) curve analysis was performed to define this optimal critical value. And, the textural features are identified using a gray level co-occurrence matrix. The proposed method increased the precision level of detection by applying a novel weighting mask and a receiver operating characteristic curve. To demonstrate the effectiveness of the proposed method, 2850 adult and non-adult images were used for experimentation.

Bayesian hierarchical model for the estimation of proper receiver operating characteristic curves using stochastic ordering

  • Jang, Eun Jin;Kim, Dal Ho
    • Communications for Statistical Applications and Methods
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    • v.26 no.2
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    • pp.205-216
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    • 2019
  • Diagnostic tests in medical fields detect or diagnose a disease with results measured by continuous or discrete ordinal data. The performance of a diagnostic test is summarized using the receiver operating characteristic (ROC) curve and the area under the curve (AUC). The diagnostic test is considered clinically useful if the outcomes in actually-positive cases are higher than actually-negative cases and the ROC curve is concave. In this study, we apply the stochastic ordering method in a Bayesian hierarchical model to estimate the proper ROC curve and AUC when the diagnostic test results are measured in discrete ordinal data. We compare the conventional binormal model and binormal model under stochastic ordering. The simulation results and real data analysis for breast cancer indicate that the binormal model under stochastic ordering can be used to estimate the proper ROC curve with a small bias even though the sample sizes were small or the sample size of actually-negative cases varied from actually-positive cases. Therefore, it is appropriate to consider the binormal model under stochastic ordering in the presence of large differences for a sample size between actually-negative and actually-positive groups.

Computer analysis of mathematical engine model including emissions (배기가스를 포함하는 수학적 엔진모델의 컴퓨터 해석)

  • 김유남;우광방
    • Journal of the korean Society of Automotive Engineers
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    • v.11 no.3
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    • pp.60-71
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    • 1989
  • In this paper the structure of an engine and its interaction are investigated by a mathematical model for the performance evaluation. The total system is composed of air-fuel inlet element, intake manifold, combustion, engine dynamics and emission. Their control functions are schematically evaluated. Because of the model constructure with general engine functions and computer simulation of the chosen engine, physical characteristics of the corresponding engine and the engine data of normal operation states are used. According to the study, it is possible to predict the mixture rate by the difference in the mass of fuel and air flowing into cylinder and to evaluate and trace dynamic characteristic of operation state under various operating conditions. The model characteristic under the transient operating condition to evaluate operating of actual engine through the result of simulation.

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Characteristic Analysis of IPMSM for Electric Vehicle Propulsion With Variable Operating Condition Based on Numerical Analysis (운전조건을 고려한 전기자동차 구동용 IPMSM의 수치해석 기반의 제 특성 해석)

  • Im, Chae-Young;Jung, Sang-Yong;Lee, Cheol-Gyun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.8
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    • pp.1502-1509
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    • 2011
  • This Paper presents characteristic analysis in terms of interior permanent magnet synchronous motor for electric vehicle propulsion using numerical analysis. Torque ripple analysis, thermal analysis, demagnetization analysis of permanent magnet and mechanical stress analysis with variable operating condition are presented. According to these characteristic analysis, both the performance of motor and possible problems during the operation are examined thoroughly in advance.

A Study on the characteristic a reflector of retaining wall by PV module (PV module을 이용한 옹벽용 반사판 특성에 관한 연구)

  • 김대근
    • Proceedings of the KIPE Conference
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    • 2000.07a
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    • pp.41-44
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    • 2000
  • This paper represent about design of the controller for battery of a reflector of retaining wall for power supply using PV Module. Simulation is represents V-I and power characteristic by Mathematica & Design Cneter 6.3 & Qnet 2.1 Finally we composed of road surface-signpost system. This system is successfully operating with high clearness lights.

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A Study on the Characteristic for EL Driving Resonant Inverter (EL 구동용 공진형 인버터 특성에 관한 연구)

  • 윤석암
    • Proceedings of the KIPE Conference
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    • 2000.07a
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    • pp.380-383
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    • 2000
  • This paper presents about EL(electro-luminescent) driver with inverter Inverter is constructed by using characteristic of FET and its output characteristics is analysed for the variation of gate bias frequency and load. The optimum operating condition of inverter is that the gate bias frequency of FET equal two resonant frequency of circuit.

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The Output Characteristics of 3kW BIPV System (건물일체형 태양광발전시스템의 실증분석)

  • Kim, Ji-Hoon;Jie, Bian Wen;Lee, Kang-Yeon;Kim, Pyoung-Ho;Oh, Geum-Gon;Baek, Hyung-Lae
    • Proceedings of the KIEE Conference
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    • 2006.04b
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    • pp.386-389
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    • 2006
  • BIPV(Building Integrated PV) system can expect dual effects that reduce expenses for establishment of PV system by adding new function as outer covering material of building expect producing the electricity. In case of PV(photovoltaic system) there are many generation differences according to the exterior environmental facts(solar cell array, design and installation condition of interactive inverter system). In this paper, we compared constitute factors of 3kW BIPV(solar cell module, inverter), operating characteristic and total system characteristic(utilization, generation efficiency, loss fact) and found out long time operating data using a watch instrumentations. By use of long time operating result, compare a totally operating characteristics, and we proposed a next building application of BIPV. BIPV system that is proposed in this paper, was established in Solar Energy research center of Chosun University, composed with system. The objective of this paper, is to provide a efficient BIPV design method through the considerations for the integration of PV system.

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Investigation on the Turbulent Flow-Field of a Small-size Axial Fan with Different Operating Points (운전점이 다른 소형 축류홴의 난류 유동장 고찰)

  • Kim, J.K.
    • Journal of Power System Engineering
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    • v.12 no.5
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    • pp.40-47
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    • 2008
  • The turbulent flow characteristics around a small-size axial fan(SSAF) for a refrigerator are strongly dependent upon the operating points. Four operating points such as $\phi$ =0.1, 0.18, 0.25 and 0.32 were adopted in this study to investigate three-dimensional turbulent flow characteristics around the SSAF by using a fiber-optic type Laser Doppler Anemometer(LDA) system. Downstream mean velocity profiles of the SSAF along the radial distance show that axial and tangential velocity components exist predominantly, except $\phi$ = 0.1, and have a maximum value at $r/R{\fallingdotseq}0.8$, but radial velocity component having a relatively small value only turns flow direction to the outside or the central part of the SSAF. The turbulent intensity shows that the radial component exists most greatly after $r/R{\fallingdotseq}0.5$. Downstream turbulent kinetic energy at $\phi$ = 0.25 and 0.32 together has the largest peak value at $r/R{\fallingdotseq}0.9$.

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Application of Receiver Operating Characteristics (ROC) Curves for Clinical Diagnostic Tests (임상진단 검사에서 ROC 곡선의 응용)

  • Pak, Son-Il;Koo, Hee-Seung;Hwang, Cheol-Yong;Youn, Hwa-Young
    • Journal of Veterinary Clinics
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    • v.19 no.3
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    • pp.312-315
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    • 2002
  • Diagnostic tests often require the determination of cut-off values that discriminate uninfected from infected individuals. The receiver operating characteristic (ROC) curve has been frequently used to attain this purpose and gives a representation of diagnostic accuracy (sensitivity and specificity) of a prediction model when varying the cut-point of a decision rule on a whole spectrum. We have written and tested a visual basic application program in EXCEL for maximum likelihood estimation of a binormal ROC curve, which also computes univariate statistics of a diagnostic test employed. Examples applying for computed tomographic images in radiology and methicillin-resistant Staphylococcus aureus research are given to illustrate this approach. This stand-alone module is available from the first author on request.

Operating Characteristic Properties of Two Types of Multi-Level Skip-Lot Sampling Plans

  • Byoung-Chul Choi
    • Communications for Statistical Applications and Methods
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    • v.2 no.2
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    • pp.358-365
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    • 1995
  • This paper presents another system of multi-level skip-lot sampling plan, which can directly retum to normal inspection from any skpping inspection level when a sudden shift for the worse in the process mean occurs. All the other properties of the proposed sampling plan are similar to those of the Choi's(1993) plan. The formula of the poerating characteristic function for the proposed n-level skip-lot sampling plan is derived. Sone poerating characteristic properties for the proposed plan are graphically compared with those of the Choi's plan.

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