• Title/Summary/Keyword: Accuracy Rate

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A Study on Forecasting Trip Distribution of Land Development Project Using Middle Zone Size And Gravity Model (중죤단위와 중력모형을 이용한 택지개발사업의 통행분포 예측방법에 관한 연구)

  • Jeong, Chang-Yong;Son, Ui-Yeong;Kim, Do-Gyeong
    • Journal of Korean Society of Transportation
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    • v.27 no.6
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    • pp.19-28
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    • 2009
  • In case of land development projects constructed, to solve induced transportation volume needs analysis of traffic demand. Trip-generation of land development projects is exactly predicted by using traffic instigating-basic-unit in each facility of land developments. But in case of a phase of trip-distribution, because a range of destinations is very enormous and it needs enormous data to reflect all of its characters, whenever trip-distribution is predicted, the method which assumes the rate of trip-distribution is same both before completion of land development projects and after is often used. But because there is no exact criterion, the method suggested above is also affected by subjective opinion. Accordingly, this study look over using trip-distribution of specific areas's DB and suggests a size of zone to predict a distribution of land development projects exactly. Also production - constrained gravity model which uses the gap between a distribution of suggested ranges and induced land development project is suggested for more exact prediction of trip-distribution. Besides accuracy of prediction is scrutinized by using Mean Squared Error.

Safety and Feasibility of Thallium-201 Myocardial SPECT with Intravenous Infusion of Disodium Adenosine Triphosphate (ATP) in the Diagnosis of Coronary Artery disease (관상동맥 질환 진단에서 ATP부하 T1-201 심근 관류 SPECT의 안전성과 유용성)

  • Pai, Moon-Sun;Park, Chan-H.;Yoon, Seok-Nam;Kim, Won;Kim, Han-Soo
    • The Korean Journal of Nuclear Medicine
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    • v.32 no.3
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    • pp.250-258
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    • 1998
  • Purpose: ATP (adenosine triphosphate) is a potent coronary vasodilator with a rapid onset of action and a very short half-life. Myocardial perfusion scintigraphy with intravenous ATP has not yet been sufficiently proven in the diagnosis, follow-up, and risk stratification of coronary artery disease. The purpose of this study was to evaluate the safety, feasibility and diagnostic accuracy of pharmacologic stress thallium-201 myocardial SPECT using an intra-venous ATP infusion in patients with suspected coronary artery disease. Materials and Methods: Thallium-201 myocardial SPECT in 319 patients with suspected coronary artery disease were performed after the infusion of ATP (0.08 mg/kg/min for 6 min). The adverse effects were carefully monitored. Coronary angiography was also performed within 3 weeks. Results: Although 76.5% of the patients had some adverse effects, they were transient, mild, and well tolerated. In all patients, the ATP infusion protocol was completed and only 2 patients required aminophylline. The adverse effects were dyspnea in 63%, headache in 31%, flushing in 21%, chest pain in 14% and abdominal discomfort in 5% of the patients. The sensitivity and specificity were 80% and 90% respectively. Conclusion: Thallium-201 myocardial SPECT after 6 min-infusion of ATP at a rate of 0.08 mg/kg/min is safe and has a diagnostic value in detecting coronary artery disease.

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Establishment of the Physicochemical and Radiological Database of Raw Materials and By-Products in Domestic Distribution (국내 유통중인 원료물질 및 공정부산물의 물리화학적 및 방사선적 특성 데이터베이스 구축)

  • Lim, Chung-Sup;Lim, Jong-Myoung;Park, Ji-Young;Chung, Kun Ho;Kim, Chang-Jong;Chang, Byung-Uck;Ji, Young-Yong
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.14 no.4
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    • pp.331-341
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    • 2016
  • To evaluate the physicochemical and radiological properties of raw materials and by-products in domestic distribution, about 220 samples with 16 species were prepared. We measured the energy spectrum and the chemical content, such as U, Th, and K, using a $LaBr_3$ scintillation detector and ED-XRF. In addition, HPGe detector was used to analyze the radioac-tivity of $^{234}Th$, $^{234}mPa$, and $^{214}Bi$ in uranium decay series and $^{228}Ac$, $^{212}Pb$, and $^{208}Tl$ in thorium decay series, and $^{40}K$. The correlation between characteristic variables, such as the count rate in several ROIs, chemical content, and radioactivity, was assessed to infer the radioactivity of natural radionuclides through a rapid screening method. Based on the results, a characteristic database for raw material and by-product in domestic distribution was established and it will provide useful information in the analysis procedure and improve the accuracy and reproducibility in the analysis of natural radionuclides.

Development of Computation Model for Traffic Accidents Risk Index - Focusing on Intersection in Chuncheon City - (교통사고 위험도 지수 산정 모델 개발 - 춘천시 교차로를 중심으로 -)

  • Shim, Kywan-Bho;Hwang, Kyung-Soo
    • International Journal of Highway Engineering
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    • v.11 no.3
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    • pp.61-74
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    • 2009
  • Traffic accident risk index Computation model's development apply traffic level of significance about area of road user group, road and street network area, population group etc.. through numerical formula or model by countermeasure to reduce the occurrence rate of traffic accidents. Is real condition that is taking advantage of risk by tangent section through estimation model and by method to choose improvement way to intersection from outside the country, and is utilizing being applied in part business in domestic. However, question is brought in the accuracy being utilizing changing some to take external model in domestic real condition than individual development of model. Therefore, selection intersection estimation element through traffic accidents occurrence present condition, geometry structure, control way, traffic volume, turning traffic volume etc. in 96 intersections in this research, and select final variable through correlation analysis of abstracted estimation elements. Developed intersection design model taking advantage of signal type, numeric of lane, intersection type, analysis of variance techniques through ANOVA analysis of three variables of intersection form with selected variable lastly, in signal crossing through three class intersection, distinction variable choice risk in model, no-signal crossing risk distinction analysis model and so on develop.

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Software Development for Dynamic Positron Emission Tomography : Dynamic Image Analysis (DIA) Tool (동적 양전자방출단층 영상 분석을 위한 소프트웨어 개발: DIA Tool)

  • Pyeon, Do-Yeong;Kim, Jung-Su;Jung, Young-Jin
    • Journal of radiological science and technology
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    • v.39 no.3
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    • pp.369-376
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    • 2016
  • Positron Emission Tomography(PET) is nuclear medical tests which is a combination of several compounds with a radioactive isotope that can be injected into body to quantitatively measure the metabolic rate (in the body). Especially, Phenomena that increase (sing) glucose metabolism in cancer tissue using the $^{18}F$-FDG (Fluorodeoxyglucose) is utilized widely in cancer diagnosis. And then, Numerous studies have been reported that incidence seems high availability even in the modern diagnosis of dementia and Parkinson's (disease) in brain disease. When using a dynamic PET iamge including the time information in the static information that is provided for the diagnosis many can increase the accuracy of diagnosis. For this reason, clinical researchers getting great attention but, it is the lack of tools to conduct research. And, it interfered complex mathematical algorithm and programming skills for activation of research. In this study, in order to easy to use and enable research dPET, we developed the software based graphic user interface(GUI). In the future, by many clinical researcher using DIA-Tool is expected to be of great help to dPET research.

A comparative study for reconstructing a high-quality NDVI time series data derived from MODIS surface reflectance (MODIS 지표 분광반사도 자료를 이용한 고품질 NDVI 시계열 자료 생성의 기법 비교 연구)

  • Lee, Jihye;Kang, Sinkyu;Jang, Keunchang;Hong, Suk Young
    • Korean Journal of Remote Sensing
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    • v.31 no.2
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    • pp.149-160
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    • 2015
  • A comparative study was conducted for alternative consecutive procedures of detection of cloud-contaminated pixels and gap-filling and smoothing of time-series data to produce high-quality gapless satellite vegetation index (i.e. Normalized Difference Vegetation Index, NDVI). Performances of five alternative methods for detecting cloud contaminations were tested with ground-observed cloudiness data. The data gap was filled with a simple linear interpolation and then, it was applied two alternative smoothing methods (i.e. Savitzky-Golay and Wavelet transform). Moderate resolution imaging spectroradiometer (MODIS) data were used in this study. Among the alternative cloud detection methods, a criterion of MODIS Band 3 reflectance over 10% showed best accuracy with an agreement rate of 85%, which was followed by criteria of MODIS Quality assessment (82%) and Band 3 reflectance over 20% (81%), respectively. In smoothing process, the Savitzky-Golay filter was better performed to retain original NDVI patterns than the wavelet transform. This study demonstrated an operational framework of gapdetection, filling, and smoothing to produce high-quality satellite vegetation index.

Improvement of COMS land surface temperature retrieval algorithm by considering diurnal variation of air temperature (기온의 일 변동을 고려한 COMS 지표면온도 산출 알고리즘 개선)

  • Choi, Youn-Young;Suh, Myoung-Seok
    • Korean Journal of Remote Sensing
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    • v.32 no.5
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    • pp.435-452
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    • 2016
  • Land Surface Temperature (LST) has been operationally retrieved from the Communication, Ocean, and Meteorological Satellite (COMS) data by the spilt-window method (CSW_v2.0) developed by Cho et al. (2015). Although the CSW_v2.0 retrieved the LST with a reasonable quality compared to the Moderate Resolution Imaging Spectroradiometer (MODIS) LST data, it showed a relatively poor performance for the strong inversion and lapse rate conditions. To solve this problem, the LST retrieval algorithm (CSW_v2.0) was updated using the simulation results of radiative transfer model (MODTRAN 4.0) by considering the diurnal variations of air temperature. In general, the upgraded version, CSW_v3.0 showed a similar correlation coefficient between the prescribed LSTs and retrieved LSTs (0.99), the relatively smaller bias (from -0.03 K to-0.012 K) and the Root Mean Square Error (RMSE) (from 1.39 K to 1.138 K). Particularly, CSW_v3.0 improved the systematic problems of CSW_v2.0 that were encountered when temperature differences between LST and air temperature are very large and/or small (inversion layers and superadiabatic lapse rates), and when the brightness temperature differences and surface emissivity differences were large. The bias and RMSE of CSW_v2.0 were reduced by 10-30% in CSW_v3.0. The indirect validation results using the MODIS LST data showed that CSW_3.0 improved the retrieval accuracy of LST in terms of bias (from -0.629 K to -0.049 K) and RMSE (from 2.537 K to 2.502 K) compared to the CSW_v2.0.

Application of SWAT-CUP for Streamflow Auto-calibration at Soyang-gang Dam Watershed (소양강댐 유역의 유출 자동보정을 위한 SWAT-CUP의 적용 및 평가)

  • Ryu, Jichul;Kang, Hyunwoo;Choi, Jae Wan;Kong, Dong Soo;Gum, Donghyuk;Jang, Chun Hwa;Lim, Kyoung Jae
    • Journal of Korean Society on Water Environment
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    • v.28 no.3
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    • pp.347-358
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    • 2012
  • The SWAT (Soil and Water Assessment Tool) should be calibrated and validated with observed data to secure accuracy of model prediction. Recently, the SWAT-CUP (Calibration and Uncertainty Program for SWAT) software, which can calibrate SWAT using various algorithms, were developed to help SWAT users calibrate model efficiently. In this study, three algorithms (GLUE: Generalized Likelihood Uncertainty Estimation, PARASOL: Parameter solution, SUFI-2: Sequential Uncertainty Fitting ver. 2) in the SWAT-CUP were applied for the Soyang-gang dam watershed to evaluate these algorithms. Simulated total streamflow and 0~75% percentile streamflow were compared with observed data, respectively. The NSE (Nash-Sutcliffe Efficiency) and $R^2$ (Coefficient of Determination) values were the same from three algorithms but the P-factor for confidence of calibration ranged from 0.27 to 0.81 . the PARASOL shows the lowest p-factor (0.27), SUFI-2 gives the greatest P-factor (0.81) among these three algorithms. Based on calibration results, the SUFI-2 was found to be suitable for calibration in Soyang-gang dam watershed. Although the NSE and $R^2$ values were satisfactory for total streamflow estimation, the SWAT simulated values for low flow regime were not satisfactory (negative NSE values) in this study. This is because of limitations in semi-distributed SWAT modeling structure, which cannot simulated effects of spatial locations of HRUs (Hydrologic Response Unit) within subwatersheds in SWAT. To solve this problem, a module capable of simulating groundwater/baseflow should be developed and added to the SWAT system. With this enhancement in SWAT/SWAT-CUP, the SWAT estimated streamflow values could be used in determining standard flow rate in TMDLs (Total Maximum Daily Load) application at a watershed.

Progesterone assays as an aid for improving reproductive efficiency in dairy cattle II. Use of plasma or milk progesterone profiles for differential diagnosis of ovarian cysts (Progesterone 농도측정(濃度測定)에 의한 유우(乳牛)의 번식효율증진(繁殖效率增進)에 관한 연구(硏究) II. 혈액(血液) 및 유즙(乳汁)중 progesterone 농도측정(濃度測定)에 의한 난소낭종(卵巢囊腫)의 감별진단(鑑別診斷))

  • Kang, Byong-kyu;Choi, Han-sun;Choi, Sang-gong;Son, Chang-ho;Chon, Hong-suk
    • Korean Journal of Veterinary Research
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    • v.34 no.1
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    • pp.181-188
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    • 1994
  • In 60 dairy cows with inactive ovaries, follicular cyst, luteal cyst, persistent corpus luteum and silent heat as diagnosed by rectal palpation, and those that had not resumed ovarian cycles until 60 days postpartum, progesterone concentrations for differential diagnosis of reproductive disorders were measured and were compared in matched plasma, skim milk and milk fat samples at 10 days interval. The incidence rate of reproductive disorders were as follows; inactive ovaries 20(33.3%), silent heat 11(18.3%), follicular cyst 7(11.7%), luteal cyst 7(11.7%), persistent corpus luteum 7(11.7%), pyometra 4(6.7%), vaginitis 2(3.3%), cystic corpus luteum 1(1.7%), and endometritis 1(1.7%), respectively. Cows having a progesterone concentration in plasma and skim milk < 1.0 ng/ml, and in milk fat < 80.0 ng/ml were considered to have inactive ovaries or follicular cyst. Those with concentrations in plasma and skim milk ${\geq}1.0ng/ml$, and in milk fat ${\geq}80.0ng/ml$ were regarded as the cases of luteal cyst or persistent corpus luteum. Progesterone concentrations in above cows did not differ significantly between the time of initial determination and the 10 days after initial determination. But progesterone concentrations in cows with silent heat did differ significantly between the time of initial determination and the 10 days after initial determination(P<0.05). The accuracy of rectal palpation for making a differential diagnosis of ovarian dysfunction, as defined on basis of progesterone concentrations, were as follows; follicular cyst 55.6%, luteal cyst 50.0%, inactive ovaries 90.5% and persistent corpus luteum 60.0%, respectively. It may be concluded that progesterone determinations at 10 days interval is practical as an aid to diagnosing ovarian dysfunction, particularly follicular cyst and luteal cyst.

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A Study on the Age Group of Elderly Driver's Accident Characteristics Using Correlation Analysis (상관분석을 이용한 고령 운전자 사고특성에 따른 연령유형 연구)

  • Ko, Eun-Hyeok;Yoon, Byoung-Jo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.37 no.5
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    • pp.827-835
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    • 2017
  • With the rapid progress of ageing several issues concurrently occur, and one important social issue that must be resolved is accidents involving Elderly drivers. Efforts to reduce the frequency of such accidents is a must in order to be prepared to face a superaged society. Currently people aged 65 or older are prescribed as an "Elderly person." Therefore, various studies concerning accidents involving Elderly drivers apply this age criteria to separate regular drivers and Elderly drivers. However, there is no criteria to practically discern Elderly drivers with certain physical features as vulnerable road users based on a level of acceptable accuracy. Therefore, this studies intends to compare the possibility of accidents by age group of Elderly drivers by correlation analysis to analyze the accident characteristics by age group. Results showed that for drivers aged 75 and older, their influence on major accident characteristics by vehicle type increased with higher age groups. In particular, passenger cars had a relatively low accident frequency rate for drivers aged between 70 and 80, but for drivers aged 75 to 84, they had higher influence on accidents for the same vehicle type. This demonstrates that as ageing progresses and the average life expectancy increases, the age span of elders continues to increase, meaning that characteristics differ by age group among the aged. This study confirmed that the influence on the possibility of accidents differs by age group among the aged.