• Title/Summary/Keyword: Counts data

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A Study of Quality Control of Nuclear Medicine Counting System and Gamma Camera (핵의학 계측기기 및 감마카메라의 정도관리 연구)

  • 손혜경;김희중;정해조;정하규;이종두;유형식
    • Progress in Medical Physics
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    • v.12 no.2
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    • pp.103-112
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    • 2001
  • Purpose: The purpose of this study was to investigate the current status of performing nuclear medicine quality control in korea and to test selected protocols of quality control of nuclear medicine counting system and gamma camera. Materials and Methods: Fifty three hospitals were included to investigate the current status of nuclear medicine quality control in korea. The precision of dose calibrator and thyroid uptake system was measured with Tc-99m 35.52 MBq for 2 minuets and Tc-99m 5.14 MBq for 10 sec every one minute, respectively. The sensitivity of CeraSPECT$^{TM}$ with low energy high resolution parallel hole collimator was measured using two cylindrical phantoms with 15 cm in diameter and 12 cm and 30 cm in heights containing Tc-99m. The correction factor for sensitivity of CeraSPECT$^{TM}$ was calculated using phantom data. The system planar sensitivity, uniformity, count rate and spatial resolution were measured for Varicam gamma camera with low energy high resolution parallel hole collimator using 140 keV centered 20% energy window, 256$\times$256 or 512$\times$512 matrix sizes. Results: The quality control of dose calibrator and well counter were showed poor performance status. On the other hand, The quality control of gamma camera and other systems were showed relatively good performance status. The results of precision of dose calibrator and thyroid uptake system was $\pm$1.4%(<$\pm$5%) and chi^2=29.7(>16.92), respectively. It showed that the sensitivity of CeraSPECT$^{TM}$ was higher in center slices compared with the edge slices. After correction of nonuniform sensitivities for patient data, it showed better results compare with prior to correction. System planar sensitivity of Varicam gamma camera was 4.39 CPM/MBq. The observed count rate at 20% loss was 102,407 counts/sec (head 1), 113,427 counts/sec (head 2), when input count rate was 81,926 counts/sec (head 1), 90,741 counts/sec (head 2). The spatial resolution without scatter medium were 8.16 mm of FWHM and 14.85 mm of FWTM. The spatial resolution with scatter medium were 8.87 mm of FWHM and 18.87 mm of FWTM. Conclusion: It is necessary to understand the importance of quality control and to perform quality control of nuclear medicine devices.vices.

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Reference Intervals from Hospital-Based Data for Hematologic and Serum Chemistry Values in Dogs (병원자료에 근거한 혈액 및 혈액화학 검사항목의 참고구간 설정)

  • Kwon, Young-Wook;Pak, Son-Il
    • Journal of Veterinary Clinics
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    • v.27 no.1
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    • pp.66-70
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    • 2010
  • Reference interval is critical for interpreting laboratory results, monitoring response to therapy and predicting the prognosis of the patients in clinical settings. The aim of the present study was to update established reference intervals for routine hematologic and serum chemistry values for a population of clinically healthy dogs (range, 1-8 years) seen in an animal hospital. Blood was obtained by venipuncture while animals were physically restrained, and samples were analyzed for 9 chemistries on MS9-5H (Melot Schloesing Lab, France) and 6 hematology on Vet Test 8008 (IDEXX, USA). Data from 105 dogs (52 males and 53 females) for hematology and 113 dogs (37 males and 76 females) for chemistry were used to determine reference intervals using the parametric, nonparametric and bootstrap methods. Prior to analysis, all parameters were tested for normal distribution using Anderson-Darling criterion. Of the 9 biochemical analytes, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, creatinine, total protein, and glucose concentrations did not fit normal distribution for both original and transformed data. All but eosinophil count satisfied normal distribution for either original or transformed data. Parametric method can be used for original cholesterol concentrations, RBC, WBC, and neutrophil counts. This technique can also be used for power-transformed values of blood urea nitrogen concentrations and for logarithm of lymphocyte and monocyte counts. Non-parametric or bootstrap method was the preferred choice for the remaining 7 biochemical parameters and eosinophil count as they did not follow normal distributions. All three statistical techniques performed in similar reference intervals. When establishing reference intervals for clinical laboratory data, it is essential to assess the distribution of the original data to increase the accuracy of the interval, and non-parametric or bootstrap methods are of alternative for the data that do not fit normal distribution.

Joint Modeling of Death Times and Number of Failures for Repairable Systems using a Shared Frailty Model (공유환경효과를 고려한 수리가능한 시스템의 수명과 고장회수의 결합모형 개발)

  • 박희창;이석훈
    • Journal of Korean Society for Quality Management
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    • v.26 no.4
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    • pp.111-123
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    • 1998
  • We consider the problem of modeling count data where the observation period is determined by the life time of the system under study. We assume random effects or a frailty model to allow for a possible association between the death times and the counts. We assume that, given a random effect or a frailty, the death times follow a Weibull distribution with a hazard rate. For the counts, given a frailty, a Poisson process is assumed with the intensity depending on time. A gamma distribution is assumed for the frailty model. Maximum likelihood estimators of the model parameters are obtained. A model for the time to death and the number of failures system received is constructed and consequences of the model are examined.

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Acoustic Emmision Characteristics according to Failure Modes of Pipes with Local Wall Thinning (감육배관의 손상모드에 따른 음향방출 특성)

  • 안석환;남기우;김선진;김진환;김현수;박인덕
    • Journal of Ocean Engineering and Technology
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    • v.16 no.5
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    • pp.66-72
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    • 2002
  • Fracture behaviors of pipes with local wall thinning are very important for the integrity of nuclear power plant. However, effects of local wall thinning on strength and fracture behaviors of piping system were not well studied. Acoustic emission(AE) has been widely used in various fields because of its extreme sensitivity, dynamic detection ability and location of growing defects. In this study, we investigated failure modes of locally wall thinned pipes and AE signals by bending test. From test results, we could be divided four types of failure modes of ovalization, crack initiation after ovalization, local buckling and crack initiation after local buckling. And fracture behaviors such as elastic region, yielding region, plastic deformation region and crack progress region could be evaluated by AE counts, accumulative counts and time-frequency analysis during bending test. The result of the frequency range is expected to be basic data that can inspect plants in real-time.

Effect of Samryungbaikchul-san on Astrocyte Activation and Apoptosis in Mouse Model of Alzheimer Disease (삼령백출산(蔘笭白朮散)이 Alzheimer's Disease 동물모델의 Astrocyte 활성화 및 Apoptosis에 미치는 영향)

  • Lee, Sang-Ryong
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.23 no.2
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    • pp.374-380
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    • 2009
  • Samryungbaikchul-san(SRBCS) has been used in oriental medicine for the treatments of gastrointestinal and neurological disorders. Here, potential protective function of SRBCS was investigated in neural tissues in Alzheimer's disease(AD) mouse model. In primary cultured cells from the spinal cord of newborn rats, treatment of ${\beta}$-amyloid peptide elevated cell counts positive to glial fibrillary acidic protein(GFAP) or caspase 3 immunoreactivity, but the co-treatment of SRBCS reduced positive cell counts. In vivo administration of scopolamine, an inhibitor of muscarinic receptor, resulted in increases in the number of glial fibrillary acidic protein(GFAP) and caspase 3-positive cells in hippocampal subfields, which was then decreased by the treatment of SRBCS or acetylcholinesterase inhibitor galathamine. The present data suggest that SRBCS may play a protective role in damaged neural tissues caused by scopolamine treatments in mice.

A Study on Antibiotics Susceptibilities of Staphylococci Isolated from the Atmosphere of Home Kitchens in Busan (주방공기중에서 분리된 포도상구균의 함생물질에 대한 감응성연구(1))

  • 박재림
    • Journal of Environmental Health Sciences
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    • v.5 no.1
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    • pp.51-57
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    • 1978
  • Antibiotics susceptibilities of Staphylococci were tested to get useful data for prevention food contamination and treatment of food poisoning. Tested were colony counts, isolation of Staphylococci, identification for the Staphylococcus aureus and resistant patterns to antimcrobial agents. The colonies and Staphylococci isolated from the atmosphere of 37 home kitchens in the morning (07:00-08:00) on Nov. 19, 1977 in Busan. The findings are as follows: 1. The average of colony counts was shown to be 9.6 ranging from 47 to 1 at mean temperature of 18$\circ$C (the highest 21$\circ$C, the lowest 15$\circ$C) 2. Out of total 37 kitchens, 18 Staphylococci were isolated from 15 kitchens with 40.5 per cent, and 4 Staphylococcus aureus were identified with 22.2 per cent from 18 Staphylococci. 3. Isolated Staphylococci were resistant to penicillin(100%), dihydrostreptomycin(93.3%), tetracycline (93.3%) and oleandomycin(66.6%), while the strains were sensitive to sulfonamide(88.6%) and colistin(83.3%). 4. Staphylococcus aureus identified were resistant to dihydrostreptomycin, penicillin and tetracycline, while the strains were sensitive to sulfonamide and colistin.

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Acoustic Emission Studies on the Structural Integrity Test of Welded High Strength Steel using Pattern Recognition (패턴인식을 이용한 고장력강의 용접 구조건전성 평가에 대한 음향방출 사례연구)

  • Kim, Gil-Dong;Rhee, Zhang-Kyu
    • Proceedings of the Safety Management and Science Conference
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    • 2008.04a
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    • pp.185-196
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    • 2008
  • The objective of this study is to evaluate the mechanical behaviors and structural integrity of the weldment of high strength steel by using an acoustic emission (AE) techniques. Simple tension and AE tests were conducted against the 3 kind of welding test specimens. In order to analysis the effectiveness of weldability, joinability and structural integrity, we used K-means clustering method as a unsupervised learning pattern recognition algorithm for obtained multivariate AE main data sets, such as AE counts, energy, amplitude, hits, risetime, duration, counts to peak and rms signals. Through the experimental results, the effectiveness of the proposed method is discussed.

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Acoustic Emission Studies on the Structural Integrity Test of Welded High Strength Steel using Pattern Recognition: Focused on Tensile Test (패턴인식을 이용한 고장력강의 용접 구조건전성 평가에 대한 음향방출 사례연구: 인장시험을 중심으로)

  • Kim, Gil-Dong;Rhee, Zhang-Kyu
    • Journal of the Korea Safety Management & Science
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    • v.10 no.4
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    • pp.127-134
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    • 2008
  • The objective of this study is to evaluate the mechanical behaviors and structural integrity of the weldment of high strength steel by using an acoustic emission (AE) techniques. Monotonic simple tension and AE tests were conducted against the 3 kinds of welded specimen. In order to analysis the effectiveness of weldability, joinability and structural integrity, we used K-means clustering method as a unsupervised learning pattern recognition algorithm for obtained multi-variate AE main data sets, such as AE counts, energy, amplitude, hits, risetime, duration, counts to peak and rms signals. Through the experimental results, the effectiveness of the proposed method is discussed.

The quantification of photon counts using the concept of candela (Candela 개념의 광량정량화 활용에 관한 연구)

  • Kim, Hyeon Sik;Choi, Eun Seo;Lee, Byeong-Il
    • Journal of Integrative Natural Science
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    • v.1 no.1
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    • pp.1-4
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    • 2008
  • We developed quantification method based on the concept of candela in physics. The measurement of fluorescence signal from a nude mouse in the research of molecular biology. In the measurement of the optical signal with CCD, the quantification method for photon counts based on bio-luminescence imaging technique can provide comparative reference data. In this paper, we described theoretical derivation of our proposed concept. We hope this method could be a useful standard reference for quantitative date analysis in optical imaging.

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A Study of Eliminating NNSS Speed Error by Use of Deviation of NNSS Position Error (NNSS 선위오차의 편차를 이용한 속도오차소법에 관한 연구)

  • 양창진
    • Journal of the Korean Institute of Navigation
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    • v.4 no.1
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    • pp.1-18
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    • 1980
  • As the NNSS system calculates ship's position by the doppler shift of the NNSS radio waves caused by the change of the distance between Transit Satellite and the ship, ship's speed error inevitably results in the position error, and moreover this kind of erroris most dominant compared with other errors especially in high speed ships and airplanes. Most NNSS receivers now in use have adoptedsuccessive short doppler counts as positioning data and by investigating the dispersion of serval successive positions calculated and by neglecting the mean position having dispersion of over certain threshold level, more accurate adn safe position is to be achieved. This paper proposes the method of finding ship's true speed by selecting a speed having least position dispersion for given successive doppler counts. And by computer simulation it was verified that the method proposed here is reasonable in finding the ship's desired correct speed together with the correct ship's position.

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