• 제목/요약/키워드: Standard error

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화질 향상을 위한 오류 은폐 기법 (Error Concealment Techniques for Visual Quality Improving)

  • 서재원
    • 한국콘텐츠학회논문지
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    • 제6권2호
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    • pp.65-74
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    • 2006
  • MPEG-2 비디오 압축열은 복잡한 부호화 알고리즘을 이용하여 압축하기 때문에 전송 오류에 매우 민감하다. 만약 패킷을 잃어버리거나 수신된 패킷에 오류가 있으면 현재 화면에 화질저하가 발생할 뿐만 아니라 화면수가 제한적이긴 하지만 뒤이어서 재생되는 화면에도 오류가 전파된다. 따라서 이런 전송오류의 영향을 막거나 최소화 하기위해서 다양한 오류 강인 부호화/복호화를 적용한다. 대표적인 오류 강인 방법이 오류 은폐 기법이다. 오류 은폐 기법은 손상된 비디오 데이터를 은폐하기 위해서 정상적으로 수신된 데이터의 공간적, 시간적 중복성을 이용한다. 손상된 데이터를 복원하기 위해 움직임 벡터를 추정하고 움직임 보상하는 것은 좋은 방법이다. 이 논문에서는 다양한 움직임 벡터 복원 방법에 기반한 오류 은폐 기법을 제안하고 일반적인 방법들과 성능을 비교한다.

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가정용 전자식 혈압계의 정확도에 대한 임상적 평가 (Clinical Evaluation of the Accuracy of Electronic Home Blood Pressure Measuring Devices)

  • 추진아
    • 기본간호학회지
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    • 제9권1호
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    • pp.101-112
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    • 2002
  • Purpose: This study evaluated the accuracy of electronic devices compared with mercury sphygmomanometer. Of 132 outpatients with electronic devices. 77 who possessed oscillometric cuff devices participated in this study. Method: When the blood pressure was measured, all electronic devices were connected by means of a Y-connector to a mercury sphygmomanometer. Using the simultaneous same arm approach, each comparison was carried out three times at 2-minute intervals. Results: Compared with the mercury sphygmomanometer, the electronic devices underestimated systolic and diastolic blood pressure, respectively by $4.0{\pm}5.8mmHg$ and $2.5{\pm}67mmHg$, which satisfies the standard error range of the American Association for the Advancement of Medical Instrumentation. According to the British Hypertension Society criteria, these differences achieved C grade for both systolic and diastolic pressure. For the graphical analysis, the differences had a tendency to fulfill the permitted error limits in both diastolic and systolic blood pressure. Moreover, the purchase duration was not correlated with the accuracy of electronic devices. Conclusion: These results indicate that difference in blood pressure between electronic devices and mercury sphygmomanometer is within the standard error. Therefore, electronic blood pressure measuring devices may be useful for therapeutic self-management of hypertension.

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Development of the Algorithm for Optimizing Wavelength Selection in Multiple Linear Regression

  • Hoeil Chung
    • Near Infrared Analysis
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    • 제1권1호
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    • pp.1-7
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    • 2000
  • A convenient algorithm for optimizing wavelength selection in multiple linear regression (MLR) has been developed. MOP (MLP Optimization Program) has been developed to test all possible MLR calibration models in a given spectral range and finally find an optimal MLR model with external validation capability. MOP generates all calibration models from all possible combinations of wavelength, and simultaneously calculates SEC (Standard Error of Calibration) and SEV (Standard Error of Validation) by predicting samples in a validation data set. Finally, with determined SEC and SEV, it calculates another parameter called SAD (Sum of SEC, SEV, and Absolute Difference between SEC and SEV: sum(SEC+SEV+Abs(SEC-SEV)). SAD is an useful parameter to find an optimal calibration model without over-fitting by simultaneously evaluating SEC, SEV, and difference of error between calibration and validation. The calibration model corresponding to the smallest SAD value is chosen as an optimum because the errors in both calibration and validation are minimal as well as similar in scale. To evaluate the capability of MOP, the determination of benzene content in unleaded gasoline has been examined. MOP successfully found the optimal calibration model and showed the better calibration and independent prediction performance compared to conventional MLR calibration.

패턴인식에 의한 기계부품 자동검사기술에 관한 연구 (A Study on Automatic Inspection Technology of Machinery Parts Based on Pattern Recognition)

  • 차보남;노춘수;강성기;김원일
    • 한국산업융합학회 논문집
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    • 제17권2호
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    • pp.77-83
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    • 2014
  • This paper describes a new technology to develop the character recognition technology based on pattern recognition for non-contacting inspection optical lens slant or precision parts, and including external form state of lens or electronic parts for the performance verification, this development can achieve badness finding. And, establish to existing reflex data because inputting surface badness degree of scratch's standard specification condition directly, and error designed to distinguish from product more than schedule error to badness product by normalcy product within schedule extent after calculate the error comparing actuality measurement reflex data and standard reflex data mutually. Developed system to smallest 1 pixel unit though measuring is possible 1 pixel as $37{\mu}m{\times}37{\mu}m$ ($0.1369{\times}10-4mm^2$) the accuracy to $1.5{\times}10-4mm$ minutely measuring is possible performance verification and trust ability through an experiment prove.

대한침구학회지 논문의 통계적 오류에 관한 연구 (An Assessment of Statistical Validity of Articles Published in the Journal of Korean Acupuncture & Moxibusition Society - from 1984 to 2002 -)

  • 이승덕
    • Journal of Acupuncture Research
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    • 제21권1호
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    • pp.176-188
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    • 2004
  • This study was carried out to investigate statistical validity of medical articles that used various statistical techniques such as t-test, analysis of variance, correlation analysis, regression analysis and chi-square test. For study 429 original articles using those statistical methods were selected from Journal of Korean Acupuncture & Moxibusition Society published from 1984 to 2002. 429 original articles were reviewed to analyzed the statistical procedures. Results are summarized as follows : 1. In this study 93 articles(21.68%) of 429 ones didn't report statement of statistical method in detail. 2. 53 articles(12.53%) didn't report p-value in correctly, and 245 articles(57.11 %) used mean${\pm}$standard error (Mean${\pm}$SEM.) and 109 articles used mean${\pm}$standard deviation(Mean${\pm}$SD.). All of 23 articles using nonparametric statistical techniques made an error to central tendency or dispersion. 3. 175 articles(59.93%) and 14 articles(4.79%) of 292 ones made an error to description of equal variances and normal distribution. 4. 99 articles(50%) of 185 ones misused t-test and 4 articles of 5 ones misused chi-square test. 5. 28 articles(73.68%) of 38 ones using discrete variable misused parametric technique such as t-test or ANOVA. 2 articles and 1 article of 125 ones choosing paired samples misused independent t-test and Mann-Whitney U test. 6. 20 articles using analysis of variance didn't use multiple comparison.

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Axial compressive behaviour of circular CFFT: Experimental database and design-oriented model

  • Khan, Qasim S.;Sheikh, M. Neaz;Hadi, Muhammad N.S.
    • Steel and Composite Structures
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    • 제21권4호
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    • pp.921-947
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    • 2016
  • Concrete Filled Fibre Reinforced Polymer Tube (CFFT) for new columns construction has attracted significant research attention in recent years. The CFFT acts as a formwork for new columns and a barrier to corrosion accelerating agents. It significantly increases both the strength capacity (Strength enhancement ratio) and the ductility (Strain enhancement ratio) of reinforced concrete columns. In this study, based on predefined selection criteria, experimental investigation results of 134 circular CFFT columns under axial compression have been compiled and analysed from 599 CFFT specimens available in the literature. It has been observed that actual confinement ratio (expressed as a function of material properties of fibres, diameter of CFFT and compressive strength of concrete) has significant influence on the strength and ductility of circular CFFT columns. Design oriented models have been proposed to compute the strength and strain enhancement ratios of circular CFFT columns. The proposed strength and strain enhancement ratio models have significantly reduced Average Absolute Error (AAE), Mean Square Error (MSE), Relative Standard Error of Estimate (RSEE) and Standard Deviation (SD) as compared to other available strength and strain enhancement ratios of circular CFFT column models. The predictions of the proposed strength and strain enhancement ratio models match well with the experimental strength and strain enhancement ratios investigation results in the compiled database.

Decimation Chain Modeling for Dual-Band Radio Receiver and Its Operation for Continuous Packet Connectivity

  • Park, Chester Sungchung;Park, Sungkyung
    • Journal of information and communication convergence engineering
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    • 제13권4호
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    • pp.235-240
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    • 2015
  • A decimation chain for multi-standard reconfigurable radios is presented for 900-MHz and 1,900-MHz dual-band cellular standards with a data interpolator based on the Lagrange method for adjusting the variable data rate to a fixed data rate appropriate for each standard. The two proposed configurations are analyzed and compared to provide insight into aliasing and the signal bandwidth by means of a newly introduced measure called interpolation error. The average interpolation error is reduced as the ratio of the sampling frequency to the signal BW is increased. The decimation chain and the multi-rate analog-to-digital converter are simulated to compute the interpolation error and the output signal-to-noise ratio. Further, a method to operate the above-mentioned chain under a compressed mode of operation is proposed in order to guarantee continuous packet connectivity for inter-radio-access technologies. The presented decimation chain can be applied to LTE, WCDMA, GSM multi-mode multi-band digital front-end which will ultimately lead to the software-defined radio.

흐름주입식 바이오센서용 기질용액 자동희석 장치 개발 (Development of an Auto Dilution Unit of Substrate Solutionfor a Flow Injection Type Biosensor)

  • 송대빈;정효석;정대홍;김성태
    • Journal of Biosystems Engineering
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    • 제31권5호
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    • pp.443-448
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    • 2006
  • For development of an on-line monitoring unit of fermentation process, an auto dilution unit based on traditional chemical and biological analytical method was developed and the performance was evaluated. The dilution unit was constructed with two syringe pumps and flow direction change valves and fully automated. Total delivery volume of two pumps using distilled water was measured to confirm the operating stability And diluted concentrations of three substrate solutions (glucose, lactic acid, ethanol) were compared with a standard method with a high performance liquid chromatograph (glucose, lactic acid) and gas chromatograph (ethanol). Relative error values of total delivery volume of the pumps were below 3% and standard deviation values were 0.003 (n=5). Relative error values of diluted concentration of the dilution unit measurements were below 2% with 1/10 of dilution ratio and 70, $80{\mu}{\ell}$ of sample volume conditions for glucose and lactic acid, 1/30 of dilution ratio and $70{\mu}{\ell}$ of sample volume conditions for ethanol, respectively. In case of the ethanol, cause of the evaporative characteristics, the relative error values showed over 5% whole experimental conditions.

3D 부품모델 실시간 인식을 위한 로봇 비전기술 개발 (Development of Robot Vision Technology for Real-Time Recognition of Model of 3D Parts)

  • 심병균;최경선;장성철;안용석;한성현
    • 한국산업융합학회 논문집
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    • 제16권4호
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    • pp.113-117
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    • 2013
  • This paper describes a new technology to develop the character recognition technology based on pattern recognition for non-contacting inspection optical lens slant or precision parts, and including external form state of lens or electronic parts for the performance verification, this development can achieve badness finding. And, establish to existing reflex data because inputting surface badness degree of scratch's standard specification condition directly, and error designed to distinguish from product more than schedule error to badness product by normalcy product within schedule extent after calculate the error comparing actuality measurement reflex data and standard reflex data mutually. Developed system to smallest 1 pixel unit though measuring is possible 1 pixel as $37{\mu}m{\times}37{\mu}m$ ($0.1369{\times}10-4mm^2$) the accuracy to $1.5{\times}10-4mm$ minutely measuring is possible performance verification and trust ability through an experiment prove.

현장여건에 따른 터빈 유량계와 오리피스 유량계의 정확도 비교 (A Comparison of Accuracy Between a Turbine and an Orifice Meter in the Field)

  • 안승희;허재영
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 1999년도 유체기계 연구개발 발표회 논문집
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    • pp.97-105
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    • 1999
  • Orifice flow meters are frequently used for measuring gas flow in gas industry. However, to insure the accuracy of the measurement, a certain length of the meter run at the upstream of the flow meter is required. The objective of this study is to analyze flow measurement errors of the orifice flow meter quantitatively for shorter lengths of the meter runs than those suggested in the standard manuals with variation of diameter ratio( $\beta$ ratio) and flow rate. The test results showed that the flow measurement errors of the orifice meter were inversely proportional to the diameter ratio. In other words, when the diameter ratio is 0.3 and 0.7, the measurement error is $-7.3\%$ and $-3.5\%$, respectively. the main reason of the measurement error is due to the swirl effect from the configuration of the meter run at the upstream of the flow meter. In case the length of the meter run is shorter than that suggested in the standard manuals, the swirl effect is not removed completely and it affects the flow meter's performance. As mentioned above, the less the pipe diameter ratio, the more the flow measurement error. It means that the swirl effect on the orifice meter increases as the $\beta$ ratio decreases.

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