• Title/Summary/Keyword: Accuracy test

Search Result 4,840, Processing Time 0.039 seconds

Development of relative radiometric calibration system for in-situ measurement spectroradiometers (현장관측용 분광 광도계의 상대 검교정 시스템 개발)

  • Oh, Eunsong;Ahn, Ki-Beom;Kang, Hyukmo;Cho, Seong-Ick;Park, Young-Je
    • Korean Journal of Remote Sensing
    • /
    • v.30 no.4
    • /
    • pp.455-464
    • /
    • 2014
  • After launching the Geostationary Ocean Color Imager (GOCI) on June 2010, field campaigns were performed routinely around Korean peninsula to collect in-situ data for calibration and validation. Key measurements in the campaigns are radiometric ones with field radiometers such as Analytical Spectral Devices FieldSpec3 or TriOS RAMSES. The field radiometers must be regularly calibrated. We, in the paper, introduce the optical laboratory built in KOSC and the relative calibration method for in-situ measurement spectroradiometer. The laboratory is equipped with a 20-inch integrating sphere (USS-2000S, LabSphere) in 98% uniformity, a reference spectrometer (MCPD9800, Photal) covering wavelengths from 360 nm to 1100 nm with 1.6 nm spectral resolution, and an optical table ($3600{\times}1500{\times}800mm^3$) having a flatness of ${\pm}0.1mm$. Under constant temperature and humidity maintainance in the room, the reference spectrometer and the in-situ measurement instrument are checked with the same light source in the same distance. From the test of FieldSpec3, we figured out a slight difference among in-situ instruments in blue band range, and also confirmed the sensor spectral performance was changed about 4.41% during 1 year. These results show that the regular calibrations are needed to maintain the field measurement accuracy and thus GOCI data reliability.

Improvements for Atmospheric Motion Vectors Algorithm Using First Guess by Optical Flow Method (옵티컬 플로우 방법으로 계산된 초기 바람 추정치에 따른 대기운동벡터 알고리즘 개선 연구)

  • Oh, Yurim;Park, Hyungmin;Kim, Jae Hwan;Kim, Somyoung
    • Korean Journal of Remote Sensing
    • /
    • v.36 no.5_1
    • /
    • pp.763-774
    • /
    • 2020
  • Wind data forecasted from the numerical weather prediction (NWP) model is generally used as the first-guess of the target tracking process to obtain the atmospheric motion vectors(AMVs) because it increases tracking accuracy and reduce computational time. However, there is a contradiction that the NWP model used as the first-guess is used again as the reference in the AMVs verification process. To overcome this problem, model-independent first guesses are required. In this study, we propose the AMVs derivation from Lucas and Kanade optical flow method and then using it as the first guess. To retrieve AMVs, Himawari-8/AHI geostationary satellite level-1B data were used at 00, 06, 12, and 18 UTC from August 19 to September 5, 2015. To evaluate the impact of applying the optical flow method on the AMV derivation, cross-validation has been conducted in three ways as follows. (1) Without the first-guess, (2) NWP (KMA/UM) forecasted wind as the first-guess, and (3) Optical flow method based wind as the first-guess. As the results of verification using ECMWF ERA-Interim reanalysis data, the highest precision (RMSVD: 5.296-5.804 ms-1) was obtained using optical flow based winds as the first-guess. In addition, the computation speed for AMVs derivation was the slowest without the first-guess test, but the other two had similar performance. Thus, applying the optical flow method in the target tracking process of AMVs algorithm, this study showed that the optical flow method is very effective as a first guess for model-independent AMVs derivation.

Development of International Genetic Evaluation Models for Dairy Cattle (홀스타인의 국제유전평가를 위한 모형개발에 관한 연구)

  • Cho, Kwang Hyun;Park, Byoungho;Choi, Jaekwan;Choi, Taejeong;Choy, Yunho;Lee, Seungsu;Cho, Chungil
    • Journal of Animal Science and Technology
    • /
    • v.55 no.1
    • /
    • pp.1-6
    • /
    • 2013
  • This study was aimed to solve the problems of current national genetic evaluation systems in Korea and its development to pass the verification processes as required by International Bull Evaluation Service (Interbull). This will enable Korea to participate in international genetic evaluation program. A total of 1,416,589 test-day milk records with calving dates used in this study were collected by National Agricultural Cooperative Federation from 2001 to 2009. Parity was limited up to fifth calving and milk production records were adjusted to cumulative 305 day lactation. The pedigree consisted of 2,279,741 animals where 2,467 bulls had 535,409 parents. A newly developed multiple trait model was used in calculation of breeding values for milk yield, milk fat, and protein yield. Data were edited with SAS (version 9.2) and R programs, and genetic parameters were estimated using VCE 6.0. Results showed a continuous increase in genetic potentials, in general, and no remarkable differences were found between performances by parity. Except fat yield, potentials in milk yield and protein yield were well calculated. We found an increased number of daughters per each top ranked 1,000 bulls in recent years of calf births compared to the cases of previous evaluations. Of the bulls ranked top 100 by our new models (multiple-trait models) we found that increased numbers of bulls were included. Of twenty eight bulls born in 2006, twenty bulls born in 2007 and eight bulls born in 2008 that were listed by new models, only 23, 12, and 2 bulls born in respective years were represented on top 100 by old single-trait models. Re-ranking of the daughters or sires by multiple-trait models suggest that this new multiple trait approach should be used for dairy cattle genetic evaluation and seed-stock selection in the future to increase the accuracy of multiple trait selection. Breeding values for these traits should also be calculated by new method for international genetic evaluation.

A Study on Obsession & Lie in College Freshmen (대학신입생의 강박증 및 허구성 경향 조사)

  • Kim, Jin-Sung;Park, Byung-Tak;Lee, Jong-Bum;Lee, Jung-Hoon;Cheung, Seung-Douck
    • Journal of Yeungnam Medical Science
    • /
    • v.5 no.1
    • /
    • pp.111-125
    • /
    • 1988
  • The authors studied obsession, using Derogatis'SCL-90, and lie tendency using MMPI, in the subjects of 2586 male and 1206 female college freshmen of Yeungnam University. The authors collected the reports of self-rating Obsession scale and Lie scale during the periods from January to February, 1988, and applied ANOVA and t-test on obsession and lie scores in order to compare than between various psychosocial factors, and sexes. The results as follows: 1. There was not significant difference in the mean average of total obsession scores between male and female students: male students scored $10.26{\pm}5.21$, female students scored $10.54{\pm}5.01$. 2. High scored items were doubting, indecisiveness, inattention, obsessive thoughts and preoccupation with accuracy. 3. 37 male students(1.4%) showed high obsession scores of 25 or higher, while 9 female students(0.7%) showed thd same scores. 4. There was strong tendency toward higher obsession scores in the students who were dissatisfied with their home atmosphere, college, department and familiarity of parents and those who had pessimistic view of self in the past, present or future in both group(respectively P<0.001). The male students who attended the department of fine arts, who grew at the Up & whose educational fees were paid by brothers & sisters showed higher level of obsession scores(respectively P<0.05, P<0.05, P<0.01). The female students who grew at the Myun & who were self-cook showed higher level of obsession scores(respectively P<0.05). 5. There was not significant difference in the mean averages of total lie scores between male and female students: male students scored $4.73{\pm}2.49$, female students scored $4.70{\pm}2.16$. 6. High scored items were NO. 14, 8, 11, 9 and 1 in the table 6. 7. 98 male students(3.7%) showed high lie scores of 70 or high, while 27 female students(2.2%) showed the same scores. 8. There was strong tendency toward higher lie scores in the students who were satisfied with their home atmosphere, college, department and familiarity of parents and those who had optimistic view of self in the past, present or future in both group(respectively P<0.001). The students who attended the department of pharmacy, music, evening programs showed higher level of lie scores(P<0.05).

  • PDF

Usefulness of serum procalcitonin test for the diagnosis of upper urinary tract infection in children (소아 상부 요로감염의 진단을 위한 혈청 procalcitonin 검사의 유용성)

  • Kim, Dong Wook;Chung, Ju Young;Koo, Ja Wook;Kim, Sang Woo;Han, Tae Hee
    • Clinical and Experimental Pediatrics
    • /
    • v.49 no.1
    • /
    • pp.87-92
    • /
    • 2006
  • Purpose : It is difficult to make a distinction between lower urinary tract infection(UTI) and acute pyelonephritis(APN) during the acute phase of febrile UTI due to nonspecific clinical symptoms and laboratory findings, especially among young children. We measured the serum procalcitonin(PCT) in children with UTI to distinguish between acute pyelonephritis and lower UTI, and to determine the accuracy of PCT measurement compared with other inflammatory markers. Methods : Serum samples were taken from children who admitted with unexplained fever or were suspected of having UTI. 51 children(mean $12.2{\pm}11.4$ months) were enrolled in this study. Leukocyte counts, erythrocyte sedimentation rates(ESR) and C-reactive protein(CRP) were also measured. Renal parenchymal involvement was assessed by $^{99m}Tc$ DMSA scintigraphy in the first 7 days after admission. PCT was measured by immunoluminometric assay. Results : PCT values were significantly correlated with the presence of renal defects in children with UTI(n=16)($5.06{\pm}12.97{\mu}g/L$, P<0.05). However, PCT values were not significantly different between children with UTI without renal damage(n=18) and children without UTI(n=17). Using a cutoff of $0.5{\mu}g/L$ for PCT and 20 mm/hr for ESR, 20 mg/L for CRP, sensitivity and specificity in distinguishing between UTI with and without renal involvement were 81.3 percent and 88.9 percent for PCT 87.5 percent and 72.2 percent for ESR, and 87.5 percent and 55.6 percent for CRP, respectively. Positive and negative predictive values were 86.7 percent and 84.2 percent for PCT and 60.9 percent and 81.8 percent for CRP, respectively. Conclusion : In febrile UTI, PCT values were more specific than CRP, ESR and leukocyte count for the identification of patients who might develop renal defects.

A Study on Hepatomegaly and Facial Telangiectasia in a Group of the Insured (간종대(肝腫大)와 안면모세혈관확장(顔面毛細血管擴張)의 보험의학적연구(保險醫學的硏究))

  • Im, Young-Hoon
    • The Journal of the Korean life insurance medical association
    • /
    • v.4 no.1
    • /
    • pp.110-132
    • /
    • 1987
  • A study on hepatomegaly detected by abdominal palpation, and facial telangiectasia in a total of 3,418 insured persons medically examined at the Honam Medical Room of Dong Bang Life Insurance Company Ltd. from February, 1984 to August, 1985 was undertaken. The results were as follows: 1) Hepatomegaly was found in 383 cases(27.5%) among the 1,395 insureds of male and in 163 cases(8.1%) among the 2,023 insureds of female. The difference of incidence of hepatomegaly between all males and females showed statistical significance(p<0.001). In each age group, the incidence of hepatomegaly in :nale was higher than that in female. The incidence of hepatomegaly in each age group in male increased cnosiderably with age; it showed 11.6%,16.2%, 42.6% and 52.9% from second to sixth decade in order, thereafter in seventh decade it decreased to 26.7%, While the incidence of hepatomegaly in female increased slightly in each age group. 2) Facial telangiectasia was found in 318 cases(22.8%) among all males and in 157 cases(7.8%) among all females. The difference of incidence of telangiectasia between all males and females showed statistical significance(p<0.001). In each age group, the incidence of telangiectasia in male was higher than that in female, except of second decade. The incidence of facial telangiectasia in each age group in male increased considerably with age; while it increased slightly in female. 3) Facial telangiectasia accompanied by hepatomegaly was found in 235 cases(61.4%) among 383 cases of hepatomegaly in male and in 69 cases(42.3%) among 163 cases of hepatomegaly in female. The difference of incidence of telangiectasia between males and females show ed statistical significance(p<0.001). 4) Facial telangiectasia without spider angiomata accompanied by hepatomegaly was found in 201 cases(52.5%) among 383 cases of hepatomegaly in all males and in 67 casgs(41.4%) among 163 cases of hepatomegaly in all females; facial spider angiomata accompanied by hepatomegaly was found in 34 cases(8.9%) among 383 cases of hepatomegaly in all males and in 2 cases(1.2%) among 163 cases of hepatomegaly in all females. 5) Abnormal SGOT activity was found in 19 cases(7.9%) among 242 cases of hepatomegaly in all males and in one case(1.5%) among 67 cases of hepatomegaly in all females. The difference of incidence of abnormal SGOT activity showed statistical significance(p<0.001). The incidence of abnormal SGOT activity by the size of hepatomegaly, that is, palpated <1 finger's breadth, <2 fingers' breadth and ${\geqq}2$ fingers' breadth, revealed 2.2%, 6.0% and 60.0% respectively in all males, while abnormal SGOT activity was found only one case in fifth decade among 67 cases of hepatomegaly in all females. 6) In ordinary medical examination(the insured amount is low) abnormal SGOT activity was found in 7 cases(4.8%) among 146 cases of hepatomegaly palpated $1\frac{1}{2}$ fingers' breadth and under, while it was not found in 37 cases of the same sized hepatomegaly in all females. Above mentioned 7 cases are thought to be very significant because 7 cases occupy 35% in 20 cases of abnormal SGOT activity with hepatomegaly. 7) Abnormal SGOT activity was found in 12 cases(4.4%) among 273 cases of hepatomegaly of "not firm" consistency, while it was found in 8 cases(22.2%) among 36 cases of hepatomegaly of "firm" consistency. The difference of incidence of abnormal SGOT activity showed statistical significance(p<0.05). 8) Abnormal SGOT activity was found in 5 cases(17.9%) among 28 cases of spider angiomata with hepatomegaly, while it was found in 10 cases(7.3%) among 166 cases of telangiectasia without spider angiomata with hepatomegaly. Owing to a small number of cases, statistical significance was not recognized, but the incidence of abnormal SGOT activity in spider angiomata cases with hepatomegaly is apt to be higher than that in telangiectasia cases without spider angiomata with hepatomegaly. 9) The incidence of abnormal SGOT activity is apt to be higher with age in male group; abnormal SGOT activity was not found among 4 cases of hepatomegaly in second decade and it was 3.8% in third decade, 4.5% in fourth decade, 9.3% in fifth decade, 17.5% in sixth decade and 33.3% in seventh decade, while the incidence of it was only one case among 67 cases in all females. 10) It is believed that the performance of liver function test to the subjects with hepatomegaly even in ordinary medical examination(the insured amount is low) will give considerable contribution for medical selection of hepatomegaly risk. 11) Age of the insured(young or old), presence of facial telangiectasia or spider angiomata especially and their severity, and consistency of enlarged liver(firm or not) should be considered to increase accuracy in evaluating hepatomegaly risk.

  • PDF

Comparison of the Role of CT and Fiberoptic Bronchoscopy in the Diagnosis of Hemoptysis (객혈 진단을 위한 CT와 가관지경의 역할 비교)

  • Choe, Kyu-Ok;Kim, Hyun-Sook;Hong, Young-Kook;Seo, Jae-Seong;Ryu, Jeong-Ah;Yang, Dong-Gyoo;Kim, Se-Kyu;Chang, Joon;Kim, Sung-Kyu;Lee, Won-Young
    • Tuberculosis and Respiratory Diseases
    • /
    • v.47 no.2
    • /
    • pp.209-217
    • /
    • 1999
  • Backgrounds: To investigate the role of CT as a screening tool and to compare the diagnostic accuracy with that of the fiberoptic bronchoscopy (FOB) in evaluating the causes of hemoptysis. Methods: The retrospective review of plain chest radiograph, CT and FOB was done in 72 patients with hemoptysis. The diagnosis were confirmed by histology (n=33), bacterial culture (n=6), cytology (n=3), serology (n=2), skin test (n= 1), clinical response (n=5), and airway disease mainly by HRCT (n=22). Results: The causes of hemoptysis were shown to be lung cancer (n=29), bronchiectasis (n=19), tuberculosis (n=12), aspergilloma (n=5), invasive aspergillosis (n=l), COPD (n=3) and others (n=3). The sensitivity was 100% and 91,7% by CT and FOB respectively. The diagnostic compatibility was 95.8% and 59.7% by CT and FOB respectively. The diagnostic compatibility in cases with central airway disease was 96.3% and 100 % in CT and FOB. In parenchymal disease, CT and FOB showed 91.3 % and 43.5 % of compatibility, respectively. airway disease, CT and FOB showed 100% and 31.8% compatibility, respectively. That is to say, CT has higher sensitivity and diagnostic compatibility than FOB for identifying the causes of hemoptysis, and is more helpful for patients with hemoptysis from parenchymal or airway disease. FOB had the advantage in obtaining histologic, cytologic and bacteriologic diagnosis with biopsy or washing Conclusion: CT should be used as the screening method before performing FOB for patients with hemoptysis who have normal or nonspecific findings or peripheral airway disease in plain chest radiograph.

  • PDF

Development of Movement Analysis Program and its Feasibility Test in Streotactic Body Radiation Threrapy (복부부위의 체부정위방사선치료시 호흡에 의한 움직임분석 프로그램 개발 및 유용성 평가)

  • Shin, Eun-Hyuk;Han, Young-Yih;Kim, Jin-Sung;Park, Hee-Chul;Shin, Jung-Suk;Ju, Sang-Gyu;Lee, Ji-Hea;Ahn, Jong-Ho;Lee, Jai-Ki;Choi, Doo-Ho
    • Progress in Medical Physics
    • /
    • v.22 no.3
    • /
    • pp.107-116
    • /
    • 2011
  • Respiratory gated radiation therapy and stereotactic body radiation therapy require identical tumor motions during each treatment with the motion detected in treatment planning CT. Therefore, this study developed a tumor motion monitoring and analysis system during the treatments employing RPM data, gated setup OBI images and a data analysis software. A respiratory training and guiding program which improves the regularity of breathing was used to patients. The breathing signal was obtained by RPM and the recorded data in the 4D console was read after treatment. The setup OBI images obtained gated at 0% and 50% of breathing phases were used to detect the tumor motion range in crenio-caudal direction. By matching the RPM data recorded at the OBI imaging time, a factor which converts the RPM motion to the tumor motion was computed. RPM data was entered to the institute developed data analysis software and the maximum, minimum, average of the breathing motion as well as the standard deviation of motion amplitude and period was computed. The computed result is exported in an excel file. The conversion factor was applied to the analyzed data to estimate the tumor motion. The accuracy of the developed method was tested by using a moving phantom, and the efficacy was evaluated for 10 stereotactic body radiation therapy patients. For the sine wave motion of the phantom with 4 sec of period and 2 cm of peak-to-peak amplitude, the measurement was slightly larger (4.052 sec) and the amplitude was smaller (1.952 cm). For patient treatment, one patient was evaluated not to qualified to SBRT due to the usability of the breathing, and in one patient case, the treatment was changed to respiratory gated treatment due the larger motion range of the tumor than treatment planed motion. The developed method and data analysis program was useful to estimate the tumor motion during treatment.

The Optimization of Reconstruction Method Reducing Partial Volume Effect in PET/CT 3D Image Acquisition (PET/CT 3차원 영상 획득에서 부분용적효과 감소를 위한 재구성법의 최적화)

  • Hong, Gun-Chul;Park, Sun-Myung;Kwak, In-Suk;Lee, Hyuk;Choi, Choon-Ki;Seok, Jae-Dong
    • The Korean Journal of Nuclear Medicine Technology
    • /
    • v.14 no.1
    • /
    • pp.13-17
    • /
    • 2010
  • Purpose: Partial volume effect (PVE) is the phenomenon to lower the accuracy of image due to low estimate, which is to occur from PET/CT 3D image acquisition. The more resolution is declined and the lesion is small, the more it causes a big error. So that it can influence the test result. Studied the optimum image reconstruction method by using variation of parameter, which can influence the PVE. Materials and Methods: It acquires the image in each size spheres which is injected $^{18}F$-FDG to hot site and background in the ratio 4:1 for 10 minutes by using NEMA 2001 IEC phantom in GE Discovey STE 16. The iterative reconstruction is used and gives variety to iteration 2-50 times, subset number 1-56. The analysis's fixed region of interest in detail part of image and compute % difference and signal to noise ratio (SNR) using $SUV_{max}$. Results: It's measured that $SUV_{max}$ of 10 mm spheres, which is changed subset number to 2, 5, 8, 20, 56 in fixed iteration to times, SNR is indicated 0.19, 0.30, 0.40, 0.48, 0.45. As well as each sphere's of total SNR is measured 2.73, 3.38, 3.64, 3.63, 3.38. Conclusion: In iteration 6th to 20th, it indicates similar value in % difference and SNR ($3.47{\pm}0.09$). Over 20th, it increases the phenomenon, which is placed low value on $SUV_{max}$ through the influence of noise. In addition, the identical iteration, it indicates that SNR is high value in 8th to 20th in variation of subset number. Therefore, to reduce partial volume effect of small lesion, it can be declined the partial volume effect in iteration 6 times, subset number 8~20 times, considering reconstruction time.

  • PDF

Compact Orthomode Transducer for Field Experiments of Radar Backscatter at L-band (L-밴드 대역 레이더 후방 산란 측정용 소형 직교 모드 변환기)

  • Hwang, Ji-Hwan;Kwon, Soon-Gu;Joo, Jeong-Myeong;Oh, Yi-Sok
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.22 no.7
    • /
    • pp.711-719
    • /
    • 2011
  • A study of miniaturization of an L-band orthomode transducer(OMT) for field experiments of radar backscatter is presented in this paper. The proposed OMT is not required the additional waveguide taper structures to connect with a standard adaptor by the newly designed junction structure which bases on a waveguide taper. Total length of the OMT for L-band is about 1.2 ${\lambda}_o$(310 mm) and it's a size of 60 % of the existing OMTs. And, to increase the matching and isolation performances of each polarization, two conducting posts are inserted. The bandwidth of 420 MHz and the isolation level of about 40 dB are measured in the operating frequency. The L-band scatterometer consisting of the manufactured OMT, a horn-antenna and network analyzer(Agilent 8753E) was used STCT and 2DTST to analysis the measurement accuracy of radar backscatter. The full-polarimetric RCSs of test-target, 55 cm trihedral corner reflector, measured by the calibrated scatterometer have errors of -0.2 dB and 0.25 dB for vv-/hh-polarization, respectively. The effective isolation level is about 35.8 dB in the operating frequency. Then, the horn-antenna used to measure has the length of 300 mm, the aperture size of $450{\times}450\;mm^2$, and HPBWs of $29.5^{\circ}$ and $36.5^{\circ}$ on the principle E-/H-planes.