• Title/Summary/Keyword: standardized value

검색결과 563건 처리시간 0.025초

PET-CT에서 CT의 관전압 및 관전류에 따른 SUV값의 변화 (The Difference of Standardized Uptake Value on PET-CT According to Change of CT Parameters)

  • 신규설;동경래
    • 대한방사선기술학회지:방사선기술과학
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    • 제30권4호
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    • pp.373-379
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    • 2007
  • 목 적: PET이 PET-CT로 오면서 가장 큰 차이를 보이고 있는 점은 감쇄보정을 위한 투과영상의 차이이다. PET CT에서는 CT영상을 감쇄보정에 이용하고 있으며, CT 요인들이 PET 영상의 감쇄보정시 영향을 줄 수 있을 것으로 예상된다. 본 연구에서는 CT의 관전압과 관전류의 변화에 따라 PET의 정량성 평가로 이용되는 SUV(standard uptake value)의 값이 변화가 있는지를 평가하였다. 재료 및 방법: Data spectrum's lung phantom을 이용하여 $^{18}F$-FDG 1.909 mCi(팬텀 1)와 $913\;{\mu}Ci$(팬텀 2) 각각 물과 함께 넣고 흔들어 균일한 상태를 만든 후, 관전압을 80 kVp, 100 kVp, 120 kVp, 140 kVp까지, 관전압변화 당 관전류 10 mA에서 100 mA까지 각각 10 mA씩 변화를 주어 CT 영상을 얻었다. PET 영상을 각각의 CT영상을 이용하여 재구성 하였으며, 같은 부위에서의 SUV값을 구하여 그 차이를 비교하였다. 결 과: 팬텀 1의 SUV는 관전압 80, 100, 120, 140 kVp CT영상을 이용했을 때, 각각 $12.26{\pm}0.009$, $12.27{\pm}0.005$, $12.27{\pm}0.006$, $12.27{\pm}0.009$로 나타났다. 팬텀 2에서는 관접압을 달리 하였을 때 각각 $4.52{\pm}0.043$, $4.53{\pm}0.004$, $4.52{\pm}0.007$, $4.52{\pm}0.005$의 SUV를 보였다. 이들은 모두 관전압을 달리 하였을 때 통계적으로 유의한 SUV 변화를 보이지 않았다. 또한 관전류의 변화에서도 팬텀 1, 2 모두에서 유의한 SUV 차이는 나타나지 않았다. 결 론: 본 연구 결과 CT 요인의 변화가 PET 영상에서 SUV에 유의한 영향을 미치지 않았다. 따라서 PET CT 이용 시 SUV에 유의한 영향 없이 임상적 조건에 맞게 CT 요인들을 변화 시키는 응용이 가능할 것으로 생각된다.

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PET/CT 장비와 영상 재구성 차이에 따른 EQ PET을 이용한 표준섭취계수의 평가 (Evaluation of Standardized Uptake Value applying EQ PET across different PET/CT scanners and reconstruction)

  • 윤석환;김병진;문일상;이홍재
    • 핵의학기술
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    • 제22권1호
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    • pp.35-42
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    • 2018
  • 양전자 방출 단층촬영에서 정량적 평가에 통상적으로 쓰이는 표준섭취계수(SUV : Standardized Uptake Value)는 종양의 병소와 병기의 진단 그리고 치료 성적 평가에 있어서 사용되고 있는 유용한 지표이다. 하지만 SUV는 환자의 체격, 검사까지의 시간, 부분용적 효과, 관심영역의 설정, 검사장비, 영상재구성 차이 등에 따라 변화 되므로 다양한 인자의 영향을 고려하여야만 한다. 그 중에서도 PET/CT 장비와 영상의 재구성 방법의 차이에 의한 SUV의 차이를 SIEMENS 사의 EQ PET을 이용하여 방사능의 차이를 보정 할 수 있게 되었다. 그러므로 본 연구에서는 phantom 실험과 FDG PET 임상영상의 SUVmax를 비교 하여 EQ PET을 적용함으로써, SUV의 변화를 평가 하고 EQ PET의 유용성에 대해서 검증해보고자 하였다. 본원의 3대의 PET/CT 장비인 Biograph true point 40, Biograph mCT 40, Biograph mCT 64 장비를 이용하여 $^{18}F-FDG$를 주입 한 NEMA IEC body phantom 영상을 획득 한 후 OSEM3D+PSF, OSEM3D+TOF, OSEM3D+PSF+TOF의 알고리즘을 이용하여 영상을 재구성 하였다. 각각 재구성된 영상에서 관심영역의 방사능 농도를 측정한 후, EARL에서 권고하는 NEMA IEC body phantom의 방사능 농도의 회복계수 값을 비교하여 서로 다른 PET system 간에 방사능 농도의 차이를 줄일 수 있는 EQ filter 값을 산출 하였다. 산출한 EQ Filter 값을 장비와 영상 재구성에 따라 적용하여 팬텀의 회복계수와 61명의 폐암환자의 FDG PET 영상에서 종양의 SUVmax를 비교 분석 하였다. 3대의 PET/CT 장비에서 영상의 재구성 알고리즘을 달리하여 획득한 phantom의 영상의 6개구의 평균 변동계수는 EQ PET 적용 전 후의 값은 OSEM3D 재구성 영상에서 각각 0.05, 0.04 OSEM3D+TOF 재구성 영상에서는 각각 0.04, 0.03, OSEM3D+PSF 재구성 영상에서는 각각 0.04, 0.03, OSEM3D+PSF+TOF 재구성 영상에서는 각각 0.03, 0.02 값을 보여 EQ PET 적용 후 팬텀의 6개 구의 평균 변동계수는 감소하였다. 임상 영상 비교 에서는 폐암환자 종양의 SUVmax는 OSEM3D, OSEM3D+TOF, OSEM3D+PSF, OSEM3D+PSF+TOF 순으로 증가하였으며, EQ PET 적용 후 재구성 영상에 대한 SUVmax는 통계적으로 유의한 차이가 없었다(p=1.000). PET/CT 영상에서 서로 다른 PET/CT 장비와 영상의 재구성 방법의 차이에 의해 발생하는 방사능 농도의 차이를 EQ PET을 이용하여 측정함으로서 장비와 영상 재구성별 방사능 농도의 편차가 감소되었다. PET 영상에서 정량적 평가에 이용되는 SUV의 편차를 줄일 수 있어 종양의 병소와 병기의 진단, 그리고 치료 성적평가의 정량적 평가 신뢰도가 향상 될 것으로 사료된다.

소아중환자를 대상으로 한 PIM Ⅱ의 타당도 평가 (Evaluating the Validity of the Pediatric Index of Mortality Ⅱ in the Intensive Care Units)

  • 김정순;부선주
    • 대한간호학회지
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    • 제35권1호
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    • pp.47-55
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    • 2005
  • Purpose: This study was to evaluate the validity of the Pediatric Index of Mortality Ⅱ(PIM Ⅱ). Method: The first values on PIM Ⅱ variables following ICU admission were collected from the patient's charts of 548 admissions retrospectively in three ICUs(medical, surgical, and neurosurgical) at P University Hospital and a cardiac ICU at D University Hospital in Busan from January 1, 2002 to December 31, 2003. Data was analyzed with the SPSSWIN 10.0 program for the descriptive statistics, correlation coefficient, standardized mortality ratio(SMR), validity index(sensitivity, specificity, positive predictive value, negative predictive value), and AUC of ROC curve. Result: The mortality rate was 10.9% (60 cases) and the predicted death rate was 9.5%. The correlation coefficient(r) between observed and expected death rates was .929(p<.01) and SMR was 1.15. Se, Sp, pPv, nPv, and the correct classification rate were .80, .96, .70, .98, and 94.0% respectively. In addition, areas under the curve (AUC) of the receiver operating characteristic(ROC) was 0.954 (95% CI=0.919~0.989). According to demographic characteristics, mortality was underestimated in the medical group and overestimated in the surgical group. In addition, the AUCs of ROC curve were generally high in all subgroups. Conclusion: The PIM Ⅱ showed a good, so it can be utilized for the subject hospital. better.

정신간호상담에서 나타난 방송통신 대학생의 자아실현 분석 (Self-Actualization of College Students in Distance Education Analyzed from Nursing Counseling)

  • 이소우;박명자
    • 대한간호학회지
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    • 제17권1호
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    • pp.33-43
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    • 1987
  • This study was to explore the level of self-actualization of the students in Korea Air and Correspondence University. The study subjects consisted of 507 students who visited the counseling center for taking advices to several psychosocial problems due to distance education through nursing counseling. The self actualization of the subjects evaluated by the self-actualization Inventory standardized by Kim and Lee in Korea. It consisted of 130 two-choice comparative value and behavior judgements. The items also consisted of two basic scales: one is inner directed scale (107 items) and the other is time competence (23 items) which included eight subscales, each of which measures a conceptually important element of self-actualization. Analysis of finding was as follows: 1) The self-actualization mean score of the total subjects was characterized by normal value within normal range of scale. The highest subscale score was NC scale: the lowest scale was EX scale. 2) The mean score of time competence scale of female student was higher than male student's time competence scale. 3) There was no significant differences in self aclualization among 4 groups in age. 4) There was also no significant differences in self-actualization between the group taken one time nursing counseling and the group taken two more times nursing counseling. 5) The problems of Job, learning, personality and further study, significantly had effects on the score of self-actualization level.

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도달시간 산정공식의 입력변수 적용범위 및 민감도 분석 (Study on the Application Limits and Sensitivity Analysis for the Parameters of Time of Concentration)

  • 김선주;강상진;이광야;박재흥
    • 한국농공학회지
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    • 제42권6호
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    • pp.72-82
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    • 2000
  • Many lot of books introduce the methods to calculate the time of concentration, and these are described as various forms of formulas. There are few formulas appropriate for our basin characteristics Therefone, there are problems to make excessive or less estimation when these formulas are used. To solve these problems, comparison of formulas and sensitivity analysis for them were made with converting parameters. Finally, Time of concentration was estimated to derive Application limits for 3 watersheds by standardized formulas. In the case of input parameters analysis, SCS formula has the highest value by the length, Kerby by the height and SCS by the slope, respectively, while Kraven formula has the lowest value among them. Concerning the relative sensitivity by Taylor series, the time of concentration showed the constant effect while increasing of the length and slope, and the length was more sensitive than the slope in parameters. Finally the standardization formula developed in this study was applied to derive application limits for 3 watersheds(total 17 subbasins). In this case, Rziha(8 subbasins) and SCS(9 subbasins) formulas were the most similar to observed data of total 17 subbasins respectively. Application limits were about 300~500$\textrm{km}^2$ area, 30~60km length and under 0.01 slope for Rziha formula and about 100~200$\textrm{km}^2$ area, 10~30km length, and over 0.01 slope for SCS formula, respectively.

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교정용 BANDS 접착에 사용되는 각종 치과용 시멘트의 유지력에 관한 비교 연구 (COMPARATIVE STUDIES ON THE RETENTIVE VALUES OF VARIOUS DENIAL CEMENTS USED TO RETAIN ORTHODONTIC BANDS)

  • 김주영;유영규
    • 대한치과교정학회지
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    • 제11권2호
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    • pp.151-160
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    • 1981
  • The purpose of this study was to compare the retentive values of various dental cements used for cementing the orthodontic bands on the teeth. Sound freshly extracted human premolar teeth were selected for the study. Eleven commercial dental cements (Zinc phosphate, reinforced Zinc-oxide eugenol, Carboxylate and Glass ionomer cements) were handled under standardized conditions. All cemented speciments were then kept in a thermostatic humidor cabinet regulated at $23{\pm}2^{\circ}C$ and more than $95\%$ relative humidity and tested after 24 hours and 1 week each. The force required to remove the cemented orthodontic bands from the teeth was determined on an Instron Universal Testing Machine using a modified specimen holding device with a cross-head speed of 0.20mm/min. The results obtained were as follows: 1, The retentive values of the band cemented with zinc phosphate cements and carboxylate cements were considerably higher than those of the reinforced zinc oxide-eugenol and glass ionomer cements. 2. There was no significant difference between the retentive value of carboxylate cements as compared with zinc phosphate cements. 3. The retentive value of the reinforced zinc oxide eugenol cements was lowest all of the coements. The retentive values expressed for all cements up to at least one week were highly but no significant difference was found between the 24-hour and 7 day time intervals.

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면 편성물의 방염처리에 의한 형태안정성의 변화 (Changes of Dimensional Stability of Cotton Knitted Fabrics after Flame Resistant Treatment)

  • 지주원
    • 한국의류학회지
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    • 제29권9_10호
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    • pp.1274-1284
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    • 2005
  • Effect of fixation methods and relaxation treatment on the dimensional stability and physical properties of MDPPA/HMM treated cotton knitted fabrics were studied. Combination of four different fixation methods - relaxation, swelling agent treatment, pad dry cure fixation, and wet fixation - were applied to flame retardant finish of 4 kinds of cotton knitted fabric with MDPPA/HMM. Then these fabrics were washed 10 times. As a result, In swelling treatment on 10G showed relatively higher value of length shrinkage than 14G. Length and width shrinkage were increased by initial washing treatment and no further change was shown after 6 washing cycles. After 10 washing cycles, length and width shrinkage decreased. The KES standardized basic value of B/W, 2HB/W and bursting strength of interlock were relatively larger than those of single jersey. The values of B/W and 2HB/W of cotton knitted fabrics were increased by relaxation and washing treatment but were decreased by swelling treatment. In addition, the bursting strength of the cotton knitted fabrics was decreased after fusing, washing and relaxation treatment.

설계초기 동선 분석을 위한 BIM기반 정량 평가지표 및 평가체계에 관한 연구 (BIM-enabled Quantitative Indicators for Analyzing Building Circulation in Early Phase of Design)

  • 신재영;이진국
    • 한국실내디자인학회논문집
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    • 제25권4호
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    • pp.147-155
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    • 2016
  • In order to ensure a certain level of the quality of design, standardized evaluation indicators are being used as an objective criterion. Even though the evaluation indicators are quantifiable, limitations such as inefficiency and inconsistency caused by manual task in the evaluation process still have been found. BIM (Building Information Modeling) technology that is commonly adopted in architectural design process provides an environment which enables us to figure out a building model to be interpreted quantitatively with the basis of the building information model. It supports quantitative, consistent, accurate and quick evaluations so as to improve quality of design even in the initial design phase. This paper aims to establish BIM-enabled quantitative indicators and an evaluation framework to analyze building circulation even in early phase of design. The indicators are composed of 4 types (relative distance, accessibility, simplicity, pedestrian friendliness) and 7 sub-types. The evaluation framework is the process to derive Parameterized Path Value (PPV) as weighting on each indicator. For demonstrating the scalability of the suggested evaluation indicators and the framework, the authors implemented an evaluation tool and a case study has been carried out by using an actual building remodel project.

가정생산 위성계정 개발 연구 (The Development of Household Satellite Account)

  • 허경옥
    • 한국생활과학회지
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    • 제13권1호
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    • pp.51-62
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    • 2004
  • This research developed satellite account for household production to measure the whole size of production in Korea. The standardized satellite account was designed on the basis of Ironmonger's IO table. Results of this research were summarized as follows. First, the economic values of male and female labor invested for household production was 1,560,000 and 5,380,000 Won, respectively. Female input was greater than male by 3.5 times. Second, the expenditure for durable goods for household production was on average 470,000 Won per year. Among the total expenditure, 36% was spent for household management activities, 25% for food preparation and 25% for cleaning and laundry. Results of examining the expenditure for durable goods in total production activities showed that more than half was spent for household production; 54% for household production, 39% for leisure, 4% for sleeping, and 3% for individual use. Third, among expenditure of consumption for intermediate foods for household production, expenditure for food was the greatest to be followed by expenditures for child care, other houseworks, and cleaning and laundry. Finally, the total value of household production in Korea turned out to reach 171 trillion won which was value of 36% of GDP(482 trillion Won) in 1999.

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Effects of Fintech on Stock Return: Evidence from Retail Banks Listed in Indonesia Stock Exchange

  • ASMARANI, Saraya Cita;WIJAYA, Chandra
    • The Journal of Asian Finance, Economics and Business
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    • 제7권7호
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    • pp.95-104
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    • 2020
  • This study examines the effect of fintech on retail banks stock return listed in Indonesia Stock Exchange for the period of 2016-2018 as today's new technology lead to the emergence of fintech companies playing the same role as retail banks in the financial industry. This study is conducted quantitatively using monthly data from January 2016 to October 2018 and uses fintech as independent variable, proxied by fintech funding frequency and fintech funding value. Data transformation is conducted due to data volatility. The data of fintech funding, both frequency and value, is transformed into standardized fintech funding and growth of fintech funding. The data is obtained from Crunchbase, while the data of stock returns is obtained from Investing. This study further analyzes the data using Fama French Three-Factor Model and panel data regression. We found that fintech has no significant effect on retail banks' stock returns listed in Indonesia Stock Exchange for the period of 2016-2018. The findings of the study provide some useful insights in understanding fintech companies' current position to retail banks in Indonesia. This study also suggests banking institutions, fintech companies, policy-makers, and others to take advantageous steps in building inclusive financial sectors.