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Model Validation of a Fast Ethernet Controller for Performance Evaluation of Network Processors (네트워크 프로세서의 성능 예측을 위한 고속 이더넷 제어기의 상위 레벨 모델 검증)

  • Lee Myeong-jin
    • Journal of KIISE:Computing Practices and Letters
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    • v.11 no.1
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    • pp.92-99
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    • 2005
  • In this paper, we present a high-level design methodology applied on a network system-on-a-chip(SOC) using SystemC. The main target of our approach is to get optimum performance parameters for high network address translation(NAT) throughput. The Fast Ethernet media access controller(MAC) and its direct memory access(DMA) controller are modeled with SystemC in transaction level. They are calibrated through the cycle-based measurement of the operation of the real Verilog register transfer language(RTL). The NAT throughput of the model is within $\pm$10% error compared to the output of the real evaluation board. Simulation speed of the model is more than 100 times laster than the RTL. The validated models are used for intensive architecture exploration to find the performance bottleneck in the NAT router.

Estimation of Mean and Variance for $NH_3-N$ data of Puyeo Intake (부여 취수장의 $NH_3-N$자료에 대한 평균 및 분산추정)

  • Kim, Hyeong-Su;Jeong, Geon-Hui;Kim, Eung-Seok;Kim, Jung-Hun
    • Journal of Korea Water Resources Association
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    • v.34 no.4
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    • pp.357-364
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    • 2001
  • Sometimes the observed data is too small to discriminate it from noise of the instrument. Say, the data can be recorded as below DL(Detection Level) value. Even though the data below Detection Level(BDL) is small vague, it can be resulted in wrong estimates for mean and variance. However, in practice, the BDL data is generally eliminated as N.D. (Not Detected) and do not record it in Korea. This study investigates the distributions according to the data values of ammonia concentration (NH$_3$-N) in Puyeo intake. Also we try to find out DL value and an appropriate method for the estimations of mean and variance of BDL values that can be discriminate the distributions. The DL is estimated by trial and error method. The appropriate method for the estimations of mean and variance of above the detection level(ADL)and BDL dada sets is selected, and the mean and variance are estimated. As a result, it is found that the Bias Corrected Maximum Likelihood Estimator is the most accurate method for NH$_3$-N in Puyeo intake.

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Toxicity of the Tiger Puffer, Fugu rubripes rubripes, Sold at Jagalchi Fish Market in Pusan (부산시내 자갈치 어시장에서 시판되는 자주복 Fugu rubripes rubripes의 독성)

  • 김지회;이태식;이희정;김광수;박정흠;변한석;손광태
    • Journal of Food Hygiene and Safety
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    • v.15 no.1
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    • pp.46-50
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    • 2000
  • Totally, twenty seven specimens of tiger puffer, Fugu rubripes rubripes were collected at Jagalchi fish market in Pusan, Korea during January, April and September in 1995. Anatomical distribution of pufferfish toxin in tiger puffer was examined by mouse bioassay. The frequency rate of toxic specimens containing $\geq$ 10 MU/g was 14.8% in liver; 16.7% in gonad; and 14.8% in skin, and no toxin was detected in muscle. The highest toxin level found was 160 MU/g in liver, 600 MU/g in gonad and 26 MU/g in skin, and each average toxin level (mean$\pm$ standard error) was 7$\pm$6, 50$\pm$35 and 5$\pm$1 MU/g, respectively. Some specimens collected in January and April were toxic, while none of the specimens collected in September showed its toxicity. Although toxicity of tiger puffer showed the seasonal variation, tested tiger puffer was evaluated as a safe seafood fur consumption, in that an acceptable level of toxin was found in the edible muscle and skin.

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Assessing Unit Hydrograph Parameters and Peak Runoff Responses from Storm Rainfall Events: A Case Study in Hancheon Basin of Jeju Island

  • Kar, Kanak Kanti;Yang, Sung-Kee;Lee, Jun-Ho
    • Journal of Environmental Science International
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    • v.24 no.4
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    • pp.437-447
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    • 2015
  • Estimation of runoff peak is needed to assess water availability, in order to support the multifaceted water uses and functions, hence to underscore the modalities for efficient water utilization. The magnitude of storm rainfall acts as a primary input for basin level runoff computation. The rainfall-runoff linkage plays a pivotal role in water resource system management and feasibility level planning for resource distribution. Considering this importance, a case study has been carried out in the Hancheon basin of Jeju Island where distinctive hydrological characteristics are investigated for continuous storm rainfall and high permeable geological features. The study aims to estimate unit hydrograph parameters, peak runoff and peak time of storm rainfalls based on Clark unit hydrograph method. For analyzing observed runoff, five storm rainfall events were selected randomly from recent years' rainfall and HEC-hydrologic modeling system (HMS) model was used for rainfall-runoff data processing. The simulation results showed that the peak runoff varies from 164 to 548 m3/sec and peak time (onset) varies from 8 to 27 hours. A comprehensive relationship between Clark unit hydrograph parameters (time of concentration and storage coefficient) has also been derived in this study. The optimized values of the two parameters were verified by the analysis of variance (ANOVA) and runoff comparison performance were analyzed by root mean square error (RMSE) and Nash-Sutcliffe efficiency (NSE) estimation. After statistical analysis of the Clark parameters significance level was found in 5% and runoff performances were found as 3.97 RMSE and 0.99 NSE, respectively. The calibration and validation results indicated strong coherence of unit hydrograph model responses to the actual situation of historical storm runoff events.

On the Usage of the Multiplication and Parentheses signs (곱셈과 괄호 기호의 사용에 대한 연구)

  • Lee, Min Jung;Lee, Yang;Yang, Sung Pil;Park, Mi Suk
    • Journal of the Korean School Mathematics Society
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    • v.15 no.4
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    • pp.627-641
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    • 2012
  • We found a few students had an error in the function and equation units, because most of mathematicians omitted the multiplication signs. In the mathematical history, the multiplication and parentheses signs had various changes. Based on the Histogenetic Principle, high level students know that the letter in the functions and equations represents a number and the related principles, so they have no big problems. But since the low level students stay in the early days in the mathematical history, they have some problems in the modern function and equation. Therefore, while we study the function and equation units with the low level students, we present that we have to be cautious when we omit the multiplication and parentheses signs.

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A study on the clinical usefulness, validity, and test-retest reliability of the Spirokit, a device that combines the pulmonary function test and respiratory muscle strength test

  • Kim, Byeong-Soo;Lee, Myung-Mo
    • Physical Therapy Rehabilitation Science
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    • v.9 no.2
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    • pp.120-130
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    • 2020
  • Objective: This study was conducted to identify the clinical usefulness, validity, and reliability of the Spirokit, a device that combines the pulmonary function test (PFT) and respiratory muscle strength (RMS) test. Design: Cross-sectional study. Methods: Forty young adults (male: 23, female: 17) participated in a PFT and a RMS test. The concurrent validity for pulmonary function was assessed by comparing data obtained from MicroQuark and the Spirokit and the agreements between the MicroRPM and the Spirokit for RMS were compared. The test-retest reliability of the Spirokit was determined by comparing data obtained from the first and second sessions. The test and retest were performed at the same time after one day for the PFT and RMS test. Validity was estimated using intraclass correlation coefficients (ICCs), and by calculating 95% limits of agreement (LoA). To estimate interrater reliability, ICCs were calculated. Results: The Spirokit showed a high agreement intra class coefficient (ICC [2, 1]): 0.978-0.999, 95% limits of agreements (95% LOA): -0.798 to 0.847 with MicroQuark. It also showed a high level of concordance ICC (2, 1): 0.992 to 0.993, 95% LOA: -9.313 to 11.169 with MicroRPM. The test-retest reliability of the Spirokit was analyzed using ICC (2, 1), and showed a high level of reliability (ICC [2,1]=0.960 to 0.998). Standard error of measurement % (SEM%) was 0.12% to 3.39%, and minimum detectable change% (MDC%) was 0.02% to 3.79%, indicating high level of reliability. Conclusions: The Spirokit is a device with high validity and reliability that can be used to simultaneously measure PFT and RMS tests.

Development of an Portable Urine Glucose Monitoring System (휴대용 뇨당 측정 시스템의 개발)

  • 박호동;이경중;윤형로
    • Journal of Biomedical Engineering Research
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    • v.23 no.5
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    • pp.397-403
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    • 2002
  • Urine glucose monitoring system is a self-monitoring system that display the glucose level by non-invasive measurement method. In this paper, We developed a noninvasive urine glucose monitoring system that improved defects of urine glucose measurement with a colorimeter method and invasive blood glucose measurement method. This system consist of bio-chemical sensor for urine glucose measurements, signal detecting part, digital and signal analysis part, display part and power supplying part. The developed bio-chemical sensor for the measurement of urine glucose has good reproducibility, convenience of handing and can be mass-produced with cheap price. To evaluate the performance of the developed system, We performed the evaluation of confidence about the detection of glucose level by a comparison between a standard instrument in measuring glucose level and the developed system using standard glucose solutions mixed with urine. Standard error was 2.85282 from the evaluation of confidence based on regression analysis. Also, In analysis of S.D(standard deviation) and C.V(coefficient of validation) that are important parameters to evaluate system using bio-chemical sensor, S.D was 10% which falls under clinically valid value, 15%, and C.V was under 5%. Consequently from the above results, compared to blood glucose measurement, the system performance is satisfactory.

Decoupling Analysis between GHGs and GDP in Korea (국내 온실가스 배출량과 경제성장 간 장단기 비동조화 분석)

  • Kim, Daesoo;Lee, Sang-youp
    • Environmental and Resource Economics Review
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    • v.28 no.4
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    • pp.583-615
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    • 2019
  • This paper investigates the level of decoupling between greenhouse gas emissions and economic growth in Korea. Despite previous studies mainly stressed the existence of the Environmental Kuznets Curve, the lack of investigations in the level of decoupling constraints further policy suggestions. This study analyzes the level of decoupling in the short- and long-term, focusing on short-term volatility of GHG emissions income elasticity. In the long run, there is no decoupling in Korea because a robust causal relationship exists between GHGs, GDP, and fossil fuels. However, the short-term volatility is clearly identified under the long-term equilibrium(coupling), indicating there is the relative decoupling in the short run. The results show that fossil fuel dependence is a significant factor that increases short-term volatility(decoupling) and breaks the causal link(coupling) between GHGs and GDP.

Fundamental Studies for the Automatic Control System in the Greenhouse Using Microcomputer(II) -A Development of a Controller for an Automatic Control System- (마이크로컴퓨터에 의한 시설재배의 자동화에 관한 기초연구(II) -자동화 시스템의 종합제어기 개발-)

  • 김진현;김철수
    • Journal of Biosystems Engineering
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    • v.20 no.1
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    • pp.73-86
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    • 1995
  • The automatic control system in the greenhouse have to be developed to the direction of considering various factors the variables such as condition of the cultivation and greenhouse, the properties and types of products. Therefore, it is more important to set up variables appropriately than the problems of automatic control system itself, and the automatic control system which satisfy these problems should be simplified in the aspect of operation. In addition, even the individual automations are not perfect yet, so more studies are required for the development of comprehensive automatic system in korea. This study was carried out to automatize environment control systems for greenhouse, especially from most intensive labor requiring parts such as watering, irrigating liquefied fertilizer, spraying chemicals, mixing and ventilation system, etc. The results are summarized as follows. 1. Control type tensiometer was expected to be desirable in the automation of watering system, therefore, a new tensiometer was designed and developed through this study. 2. The chemical spraying system developed through this study was found to be excellent in the aspect of operation. 3. When pulse type water discharge meter was used in the mixing of liquefied fertilizer and chemical solution, the error of mixing were range $\pm$0.1~0.15%. 4. The water level switch of electrod type used for controlling water level was found to be affective in both control performance and operation cost. 5. The water and level control system can be omitted if each tank size are standardized in accordance with greenhouse size, therefore, the installation cost might be significantly reduced. 6. The developed general controller was excellent in hardware parts, but still remained to be improved in software parts.

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Evaluation of stress distribution with wind speed in a greenhouse structure

  • Hur, Deog-jae;Noh, Jung-Hun;Lee, Hyun ju;Song, Hyoung woon
    • Wind and Structures
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    • v.27 no.5
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    • pp.347-356
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    • 2018
  • In this paper, stress distribution for a structurally stable greenhouse is considered in the present paper with subsequent investigation into the detailed stress distribution contour with the variation of self-weight and wind pressure level designation method under wind velocity of less than 30 m/sec. For reliable analysis, wind pressure coefficients of a single greenhouse unit were modeled and compared with experiment with correlation coefficient greater than 0.99. Wind load level was designated twofold: direct mapping of fluid dynamic analysis and conversion of modeled results into wind pressure coefficients ($C_P$). Finally, design criteria of EN1991-1-4 and NEN3859 were applied in terms of their wind pressure coefficients for comparison. $C_P$ of CFD result was low in the most of the modeled area but was high only in the first roof wind facing and the last lee facing areas. Besides, structural analysis results were similar in terms of stress distribution as per EN and direct mapping while NEN revealed higher level of stress for the last roof area. The maximum stress levels are arranged in decreasing order of mapping, EN, and NEN, generating 8% error observed between the EN and mapping results under 30 m/sec of wind velocity. On the other hand, effect of dead weight on the stress distribution was investigated via variation of high stress position with wind velocity, confirming shift of such position from the center to the forward head wind direction. The sensitivity of stress for wind velocity was less than 0.8% and negligible at wind velocity greater than 20 m/sec, thus eliminating self-weight effect.