• Title/Summary/Keyword: Quantitative parameters

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Signal Level Analysis of a Camera System for Satellite Application

  • Kong, Jong-Pil;Kim, Bo-Gwan
    • Proceedings of the KSRS Conference
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    • 2008.10a
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    • pp.220-223
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    • 2008
  • A camera system for the satellite application performs the mission of observation by measuring radiated light energy from the target on the earth. As a development stage of the system, the signal level analysis by estimating the number of electron collected in a pixel of an applied CCD is a basic tool for the performance analysis like SNR as well as the data path design of focal plane electronic. In this paper, two methods are presented for the calculation of the number of electrons for signal level analysis. One method is a quantitative assessment based on the CCD characteristics and design parameters of optical module of the system itself in which optical module works for concentrating the light energy onto the focal plane where CCD is located to convert light energy into electrical signal. The other method compares the design\ parameters of the system such as quantum efficiency, focal length and the aperture size of the optics in comparison with existing camera system in orbit. By this way, relative count of electrons to the existing camera system is estimated. The number of electrons, as signal level of the camera system, calculated by described methods is used to design input circuits of AD converter for interfacing the image signal coming from the CCD module in the focal plane electronics. This number is also used for the analysis of the signal level of the CCD output which is critical parameter to design data path between CCD and A/D converter. The FPE(Focal Plane Electronics) designer should decide whether the dividing-circuit is necessary or not between them from the analysis. If it is necessary, the optimized dividing factor of the level should be implemented. This paper describes the analysis of the electron count of a camera system for a satellite application and then of the signal level for the interface design between CCD and A/D converter using two methods. One is a quantitative assessment based on the design parameters of the camera system, the other method compares the design parameters in comparison with those of the existing camera system in orbit for relative counting of the electrons and the signal level estimation. Chapter 2 describes the radiometry of the camera system of a satellite application to show equations for electron counting, Chapter 3 describes a camera system briefly to explain the data flow of imagery information from CCD and Chapter 4 explains the two methods for the analysis of the number of electrons and the signal level. Then conclusion is made in chapter 5.

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The Study on Usefulness of the Standardized Information of Nuclear Medicine Scan in Function Evaluation of the Salivary Glands (침샘의 기능평가에서 핵의학 검사의 표준화된 정보제공의 유용성 연구)

  • Pyo, Sungjai;Han, Jaebok;Choi, Namgil
    • Journal of the Korean Society of Radiology
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    • v.9 no.6
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    • pp.357-362
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    • 2015
  • This study was to evaluate the usefulness through the comparison of patients group and healthy control group by acquiring a variety of functional parameters index from time-activity curves of salivary gland scan using 99mTc-pertechnetate. From December 2014 to February 2015, had the targets of 30 patients with dry mouth and 10 people in healthy control group underwent the salivary gland scan. After intravenous injection of 370 MBq of 99mTc-pertechnetate, Vitamin C powder stimulation was administerd orally at 20 min and then 10 minutes were taken scan. The method of quantitative analysis was as follows, the time-activity curve was drawn after the parotid gland and submandible gland were prescribed as a region of interest, a variety of function parameters index was obtained in each position of the curve, and the patients group and the control group were compared. As for the methods applied in comparison and measurement, uptake ratio (UR), time at maximum counts (Tmax), time at minimum counts (Tmin), maximum accumulation (MA), accumulation velocity, maximum secretion (MS), maximum stimulation secretion (MSS), and secretion velocity (SV) were used. In the comparison of functional parameters index of patient group and normal group, the healthy normal group showed significant difference compared to the patient group in all indices except for the minimum radioactivity time (Tmin), and also in terms of variation over time the normal group showed significant difference compared to the patient group (p<0.05). Consequently, it was considered that the quantitative analysis that used a variety of function parameters index would be useful for evaluating the function of the salivary glands of the patients with dry mouth as an objective and standardized information.

Consideration of Normal Variation of Perfusion Measurements in the Quantitative Analysis of Myocardial Perfusion SPECT: Usefulness in Assessment of Viable Myocardium (심근관류 SPECT의 정량적 분석에서 관류정량값 정상변이의 고려: 생존심근 평가에서의 유용성)

  • Paeng, Jin-Chul;Lim, Il-Han;Kim, Ki-Bong;Lee, Dong-Soo
    • Nuclear Medicine and Molecular Imaging
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    • v.42 no.4
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    • pp.285-291
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    • 2008
  • Purpose: Although automatic quantification software of myocardial perfusion SPECT provides highly objective and reproducible quantitative measurements, there is still some limitation in the direct use of quantitative measurements. In this study we derived parameters using normal variation of perfusion measurements, and tried to test the usefulness of these parameters. Materials and Methods: In order to calculate normal variation of perfusion measurements on myocardial perfusion SPECT, 55 patients (M:F = 28:27) of low-likelihood for coronary artery disease were enrolled and $^{201}TI$ rest/$^{99m}Tc$-MIBI stress SPECT studies were performed. Using 20-segment model, mean (m) and standard deviation (SD) of perfusion were calculated in each segment. As a myocardial viability assessment group, another 48 patients with known coronary artery disease, who underwent coronary artery bypass graft surgery (CABG) were enrolled. $^{201}TI$ rest/$^{99m}Tc$-MIBI stress / $^{201}TI$ 24-hr delayed SPECT was performed before CABG and SPECT was followed up 3 months after CABG. From the preoperative 24-hr delayed SPECT, $Q_{delay}$ (perfusion measurement), ${\Delta}_{delay}$ ($Q_{delay}$ - m) and $Z_{delay}$ (($Q_{delay}$ - m)/SD) were defined and diagnostic performances of them for myocardial viability were evaluated using area under curve (AUC) on receiver operating characteristic (ROC) curve analysis. Results: Segmental perfusion measurements showed considerable normal variations among segments. In men, the lowest segmental perfusion measurement was $51.8{\pm}6.5$ and the highest segmental perfusion was $87.0{\pm}5.9$, and they are $58.7{\pm}8.1$ and $87.3{\pm}6.0$, respectively in women. In the viability assessment $Q_{delay}$ showed AUC of 0.633, while those for ${\Delta}_{delay}$ and $Z_{delay}$ were 0.735 and 0.716, respectively. The AUCs of ${\Delta}_{delay}$ and $Z_{delay}$ were significantly higher than that of $Q_{delay}$ (p = 0.001 and 0.018, respectively). The diagnostic performance of ${\Delta}_{delay}$, which showed highest AUC, was 85% of sensitivity and 53% of specificity at the optimal cutoff of -24.7. Conclusion: On automatic quantification of myocardial perfusion SPECT, the normal variation of perfusion measurements were considerable among segments. In the viability assessment, the parameters considering normal variation showed better diagnostic performance than the direct perfusion measurement. This study suggests that consideration of normal variation is important in the analysis of measurements on quantitative myocardial perfusion SPECT.

Usefulness of the quantitative analysis by using the functional parameter index from dynamic salivary glands scintigraphy (동적 타액선 신티그라피에서 기능적 매개변수 지표를 활용한 정량 분석의 유용성)

  • Shin, Chae Ho;Kim, Bong Su;Cho, Yong Gyi;Jo, Jin Woo;JIn, Sung Eun;Pyo, Sung Jai
    • The Korean Journal of Nuclear Medicine Technology
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    • v.19 no.2
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    • pp.81-86
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    • 2015
  • Purpose This study was to evaluate the usefulness through the comparison of patients group and healthy control group by acquiring a variety of functional parameters index from time-activity curves of salivary gland scintigraphy using $^{99m}Tc$. Materials and Methods From December 2014 to February 2015 with the targets of 30 patients in the patient group who presented themselves with xerostomia and underwent the salivary gland scan and 10 people in healthy control group, approximately 30 minutes of dynamic Scan was carried out after the intravenous bolus injection of 370 MBq of $^{99m}TcO_4{^-}$ and per os stimulation with Vitamin C powder 20 minutes after the injection. The method of quantitative analysis was as follows, the time-activity curve was drawn after the parotid gland and submandible gland were prescribed as a region of interest, a variety of functional parameters index was obtained in each position of the curve, and the patients group and the control group were compared. Results As for the methods applied in comparison and measurement, uptake ratio (UR), time at maximum counts (Tmax), time at minimum counts (Tmin), maximum accumulation (MA), accumulation velocity, maximum secretion (MS), maximum stimulation secretion (MSS), and secretion velocity (SV) were used. In the comparison of functional parameters index of patient group and normal group, the healthy normal group showed significant difference compared to the patient group in all indices except for the minimum radioactivity time (Tmin), and also in terms of variation over time the normal group showed significant difference compared to the patient group (p<0.05). Conclusion Consequently, it was considered that the quantitative analysis that used a variety of functional parameters index would be useful for evaluating the function of the salivary glands of the patients with xerostomia as an objective and standardized information.

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Quantitative Analysis of Feldspar Mixture Samples Using the Rietveld Refinement Method (Rietveld Refinement 방법을 응용한 장석 혼합시료의 정량분석 연구)

  • Shim, Sang-Heon;Ahn, Jung-Ho;Kim, Soo-Jin
    • Journal of the Mineralogical Society of Korea
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    • v.7 no.1
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    • pp.62-79
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    • 1994
  • The quanttative and structural analysis of the binary standard mixtures of albite and quartz, and microcline and albite were carried out using the Rietveld refinement method in order to investigate the accuracy and precision of the method. The quantitative analysis using the Rietveld method results in a standard deviation of 4 wt % for the albite-quartz standard mixtures and 1 wt % for the microcline-albite standard mixtures, suggesting that its accuracy is far better than that of the conventional XRD method in which only a few selected peaks are utilized. Furthermore, the unit-cell parameters of component minerals in mixtures were also estimated accurately during the analysis. It was observed that the refined weight fractions deviate systematically from their measured values when the method is applied to the mixtures that contain minerals with different degrees of preferred orientation, such as albite-quartz mixtures. The preferred orientation parameters and R-values suggest that the systematic deviation is caused as a result of the preferred orientation effect of feldspar crystallites. It is evident that the preferred orientation corrections are of help for the accurate determination of unit-cell parameters, although they may not improve the result of quantitative analysis significantly. The refined weight fraction of the mineral with higher degree of preferred orientation in mixture is greater than the measured one. This is apparently caused by the effect of geometry of feldspar crystallites in the surface of the mounted sample. The Rietveld refinement method minimizes the problems inherent in the traditional XRD methods, such as the line overlap, primary extinction, and preferred orientation effect, by fitting every data point in a whole pattern explicitly. Furthermore, accurate unit-cell parameters as well as scale factors that can be obtained from the Rietveld refinement are used for the quqantification. The present stdudy demonstrates that the Rietveld method yields far more accurate analytical result than the conventional XRD quantitative analysis method does.

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Comparison of Impedance Parameters and Occupational Therapy Evaluation in the Paretic and Non-paretic Upper Extremity of Hemiplegic Stroke Patients

  • Yoo, Chan-Uk;Kim, Jaehyung;Hwang, Youngjun;Kim, Gunho;Shin, Yong-Il;Jeon, Gyerok
    • Journal of Korea Multimedia Society
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    • v.20 no.12
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    • pp.1980-1991
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    • 2017
  • Many stroke patients undergoing rehabilitation therapy require a quantitative indicator for the evaluation of body function in paretic and non-paretic regions. In this study, the impedance parameters were acquired to assess the physical status in the upper extremity of thirty six stroke patients with hemiplegia caused by cerebral hemorrhage (10 patients) and cerebral infarction (26 patients), using bioelectrical impedance. Prediction marker (PM), phase angle (PA), PM/PA, and resistance (R) versus reactance ($X_c$) were utilized to evaluate the functional status of the paretic and non-paretic regions. In addition, the hand grip strength (HGS) and the pinch strength (lateral, palmer, tip) were measured on the upper extremity of hemiplegic stroke patients. PM was distributed in inversely proportional to HGS, but PA was distributed in proportional to HGS. However, there were a number of patients with HGS of 0, regardless of the impedance parameters (PM, PA, R vs. $X_c$). Paretic and non-paretic status in upper extremity of these patients could not be analyzed using impedance parameters. At the rehabilitation therapist's instructions, they were unable to move the hand and fingers of the paretic upper extremity by cranial nerve damage, motor nerve damage, and severe cognitive decline.

Calibration of the WASP4 Model Applied to Lake Paldang (WASP4 모형의 매개변수 추정 - 팔당호(八堂湖)를 중심으로 -)

  • Cho, Hong Yeon;Jun, Kyung Soo;Lee, Kil Seong;Han, Kwang Suk
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.13 no.4
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    • pp.177-188
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    • 1993
  • Model parameters of the WASP4 applied to Lake Paldang were estimated. The methodology is based on grouping water quality constituents and relevant parameters and successively estimating each group of parameters by a trial-and-error procedure. Chlorophyll a, nitrogen cycles, phosphorus cycles, BOD and DO were simulated at the complexity level 4. A water budget analysis using the monthly records of reservoir inflows and outflows in 1989 and 1990 was made to determine seasonally-averaged flowrates at model boundaries. Estimated flowrates were used, together with the seasonal average of water quality measurements in 1989 and 1990 for the calibration and verification, respectively, of the model. Grouping water quality constituents and associated parameters proved to be efficient in estimating a number of model parameters. From the results of model calibration and verification, it was found that quantitative evaluations of nonpoint and benthic sources of organic matters are essential. Benthic sources near the entrance of the Kyeongancheon were the most significant.

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The Analysis of Trends in Complementary and Alternative Therapy (CAT) in Nursing Research in Korea (보완. 대체요법관련 국내 간호연구의 동향분석)

  • Han Kyung-Soon;Im Nan-Young;Song Kyung-Ae;Hong Young-Hye;Kim Jong-Im;Kim Kyung-Hee;Cho Nam-Ok
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.10 no.3
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    • pp.392-398
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    • 2003
  • Purpose: The purpose of this study was to analyze trends in complementary and alternative therapy in nursing research in Korea. Method: The researchers examined academic theses and dissertations published from 1990 to 2002, and 151 articles were used for the analysis. Result: Nursing research on CAT increased rapidly from 1995 Articles with quantitative research designs made up 93.9% of the total and there were more experimental studies than non-experimental studies. Patients who had surgery, mental disorders, renal failure, hypertension, arthritis, dementia & cancer were the most frequently participants in studies on CAT. The type of CAT used in nursing research were mind-body therapy (65.8%), manual healing therapy (28.7%), phamacologic & biological therapy (3.7%), bioelectromagnetics (0.9%) and herbal therapy (0.9%). In 44 articles both psychological and physiological parameters were used as dependent variables. In 34 articles only physiological parameters were used and in 13 only psychological parameters. The most frequently used physiological parameters in CAT were pain, physiological function and vital signs, while the most used psychological parameters were anxiety, depression and stress. Conclusion: More studies about CAT are needed to extend the role and fields for professional nursing. There is a need to conduct qualitative studies in nursing about the experiences of patients who receive CAT and nurses who use CAT.

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Assessment of Incipient Decay of Radiata Pine Wood Using Stress-wave Technique in the Transverse Direction (횡단방향(橫斷方向) 응력파(應力波) 방법(方法)에 의(依)한 라디에타소나무의 초기부후(初期腐朽) 평가(評價))

  • Kim, Gyu-Hyeok;Jee, Woo-Guen;Ra, Jong-Bum
    • Journal of the Korean Wood Science and Technology
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    • v.24 no.3
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    • pp.18-27
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    • 1996
  • The feasibility of using stress-wave technique in the transverse direction for the assessment of early stages of decay was investigated using compression test specimens having different annual ring orientations subjected to decay by Tyromyces palustris for various time intervals. Decay detection, quantitative assessment of decay, and the prediction of residual strength of decayed wood with less than five percent weight loss can be feasible using stress-wave parameters (wave velocity, wave impedance, and stress-wave elasticity) and their percent reduction due to decay, measured by stress-wave technique in the transverse direction. The use of stress-wave technique in the transverse direction for the application of this technique to structural members in service is desirable, when considering the easiness of attachment of accelerometers of stress-wave measuring device on the surface of members and also accurate detection of localized decayed areas. In stress-wave technique in the transverse direction, stress-wave parameters measured were different according to the angles between wave propagation path and annual ring, due to the anisotropy of wood structure. Therefore, it is recommended to use percent reduction in stress-wave parameters instead of stress-wave parameters. This evaluation method using percent reduction in stress-wave parameters is ideal when it is impossible to observe annual ring orientation on the transverse surface of wood.

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A Study on Terrain Classification and Interpolation in Digital Terrain Model (수치지형모델에 있어서 지형분류와 보간에 관한 연구)

  • Yeu, Bock-Mo;Kwon, Hyon;Kim, In-Sup
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.7 no.2
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    • pp.53-61
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    • 1989
  • In this paper the quantitative classification parameters of terrain which can be practicable to the interpolation of digital terrain model forming a regular grid pattern have been suggested and objective terrain classification have been established by making a cluster analysis using these parameters. Also, interpolation suitable to the classification of terrain has been used by making a descriminant alaysis from description parameters of terrains. The terrain classification in this paper was dependent upon two parameters of the ratio horizontal area to inclined area and the magnitude of harmonic vectors. And the studying area was seperated to three groups of terrains by these two parameters. Three groups of terrains could be classified into the discriminant functions. By determining the ratio of area and harmonic vector magnitude in any terrains using the above discriminant function, it was possible to discriminate the terrains to apply the interpolation practicable to the terrain characteristics.

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