• Title/Summary/Keyword: standardized coefficient

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Study of Apparent Diffusion Coefficient Changes According to Spinal Disease in MR Diffusion-weighted Image

  • Heo, Yeong-Cheol;Cho, Jae-Hwan
    • Journal of Magnetics
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    • v.22 no.1
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    • pp.146-149
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    • 2017
  • In this study, we compared the standardized value of each signal intensity, the apparent diffusion coefficient (ADC) that digitizes the diffusion of water molecules, and the signal to noise ratio (SNR) using b value 0 400, 1400 ($s/mm^2$). From March 2013 to December 2013, patients with suspicion of simple compound fracture and metastatic spine cancer were included in the MR readout. We used a 1.5 Tesla Achieva MRI system and a Syn-Spine Coil. Sequence is a DWI SE-EPI sagittal (diffusion weighted imaging spin echo-echo planar imaging sagittal) image with b-factor ($s/mm^2$) 0, 400, 1400 were used. Data analysis showed ROI (Region of Interest) in diseased area with high SI (signal intensity) in diffusion-weighted image b value 0 ($s/mm^2$) Using the MRIcro program, each SI was calculated with images of b-value 0, 400, and 1400 ($s/mm^2$), ADC map was obtained using Metlab Software with each image of b-value, The ADC is obtained by applying the ROI to the same position. The standardized values ($SI_{400}/SI_0$, $SI_{400}/SI_0$) of simple compression fractures were $0.47{\pm}0.04$ and $0.23{\pm}0.03$ and the standardized values ($SI_{400}/SI_0$, $SI_{400}/SI_0$) of the metastatic spine were $0.57{\pm}0.07$ and $0.32{\pm}0.08$ And the standardized values of the two diseases were statistically significant (p < 0.05). The ADC ($mm^2/s$) for b value 400 ($s/mm^2$) and 1400 ($s/mm^2$) of the simple compression fracture disease site were $1.70{\pm}0.16$ and $0.93{\pm}0.28$ and $1.24{\pm}0.21$ and $0.80{\pm}0.15$ for the metastatic spine. The ADC ($mm^2/s$) for b value 400($s/mm^2$) was statistically significant (p < 0.05) but the ADC ($mm^2/s$) for b value 1400 (p > 0.05). In conclusion, multi - b value recognition of signal changes in diffusion - weighted imaging is very important for the diagnosis of various spinal diseases.

Principal Component Analysis with Coefficient of Variation Matrix (변동계수행렬을 이용한 주성분분석)

  • Kim, Ji-Hyun
    • The Korean Journal of Applied Statistics
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    • v.28 no.3
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    • pp.385-392
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    • 2015
  • Principal component analysis (PCA), a dimension-reduction technique, is usually implemented after the variables are standardized when the measurement unit of variables are different. To standardize a variable we divide it by its standard deviation. But there is another way to transform a variable to be independent of its measurement unit. It is to divide it by its mean rather than standard deviation. Implementing PCA on standardized variables is equivalent to implementing PCA with a correlation matrix of original variables. Similarly, implementing PCA on the transformed variables divided by their means is equivalent to implementing PCA with a matrix related to the coefficients of variation of the original variables. We explain why we need to implement PCA on the variables transformed by their means.

The Application of Strategic Management Accounting: Evidence from the Consumer Goods Industry in Vietnam

  • NGUYEN, Thieu Manh;NGUYEN, Thanh Thi
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.10
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    • pp.139-146
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    • 2021
  • This article analyzes factors affecting the application of strategic management accounting in different enterprises in Vietnam's consumer goods industry, providing more empirical evidence on factors affecting the application of strategic management accounting. The research method used a questionnaire survey of managers at all levels, chief accountants, and accountants from 72 consumer goods enterprises in Vietnam. The survey results collected 290 questionnaires, however, due to invalid questionnaires with many blank cells, 284 questionnaires were finally selected. Quantitative research was carried out with SPSS 25 software. Research results show that 6 factors have a positive influence on the application of strategic management accounting including awareness of the business market, business strategy, technology, corporate culture, qualification of management accountants, decentralization of management, in which technology has the strongest influence on the application of strategic management accounting in consumer goods enterprises in Vietnam. The standardized Beta coefficient extracted from the multiple linear regression equation reveals that the technology factor has a high standardized Beta coefficient (0.176) compared to other factors. Based on the research results, the author has proposed recommendations to improve the ability of consumer goods businesses to successfully apply strategic management accounting techniques, thereby contributing to improving competitiveness and performance of consumer goods enterprises.

The Effects of Simulation Practicum using a Standardized Patient on Nursing Students' Communication Skills, Problem-Solving Skills, Critical Thinking Dispositions, and Clinical Competency (표준화 환자를 적용한 시뮬레이션 수업이 간호대학생의 의사소통능력, 문제해결능력, 비판적 사고성향 및 임상수행능력에 미치는 효과)

  • Chung, Su Kyoung;Kim, Kyoung Ah;Jeong, Eun Young
    • Journal of Home Health Care Nursing
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    • v.23 no.2
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    • pp.186-194
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    • 2016
  • Purpose: The purpose of this study was to evaluate the effects of standardized patient simulation on nursing students' communication skills, problem-solving skills, critical thinking dispositions, and clinical competency. Methods: A one-group pretest-posttest design was used. Data were collected from a convenient sample of 47 junior nursing students at W University. Scenarios to train SP and checklists to evaluate the students''competence were developed by our research team. The collected data were analyzed with descriptive analysis t-test, Pearson's Correlation Coefficient and Cronbach's ${\alpha}$ using SPSS WIN 21.0 Program. Results: The simulation practicum using a standardized patient was conducted based on four steps, namely, selections of scenario modules, standard patient training, implementation, and evaluation. The differences between the pre and post-test scores of problem-solving skills(t=-2.94, p=.005) and clinical competency(t=-2.84, p=.007) were statistically significant. But communication skill(t=-.32, p=.747) and critical thinking(t=-.68, p=.498) was not different in group. Conclusion: Standardized patient simulation in nursing education may be useful the improvement of problem-solving skills and clinical competency.

Comparision of Test Methods for Estimating Chloride Ion Diffusion Coefficient in Concrete (콘크리트중의 염소이온 확산계수 추정 실험법의 비교)

  • 문한영;김홍삼;문재흠;한아름
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.10a
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    • pp.787-790
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    • 1999
  • To estimate durability of reinforced concrete structures located in or nearby seawater, many different kinds of accelerated tests for evaluation of chloride ion permeation in concrete were proposed. At present the only standardized test is the ASTM C 1202(RCP test). This test method is used to estimate the concrete's resistivity of the chloride penetration in concrete by using the total charges passed and sometimes used to calculate the chloride diffusion coefficients. However, this test may lead to an erroneous chloride diffusion coefficient. So this test method was compared with the modified Dhir's test and the traditional concentration diffusion test. Experimental results showed that the diffusion coefficients determined the RCP test and the PD Index gave wrongous values, but the diffusion coefficient acquired by considering a migration term was nearly the same to the CD Test.

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Sensitivity Analysis of Creep and Shrinkage Effects of Prestressed Concrete Bridges (프리스트레스트 콘크리트 교량의 크리프와 건조수축효과의 민감도 해석)

  • 오병환;양인환
    • Proceedings of the Korea Concrete Institute Conference
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    • 1998.10b
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    • pp.656-661
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    • 1998
  • This paper presents a method of statistical analysis and sensitivity analysis of creep and shrinkage effects in PSC box girder bridges. The statistical and sensitivity analyses are performed by using the numerical simulation of Latin Hypercube sampling. For each sample, the time-dependent structural analysis is performed to produce response data, which are then statistically analyzed. The probabilistic prediction of the confidence limits on long-term effects of creep and shrinkage is then expressed. Three measures are examined to quantify the sensitivity of the outputs to each of the input variables. These are rank correlation coefficient(RCC), partial rank correlation coefficient(PRCC) and standardized rank regression coefficient(SRRC) computed on the ranks of the observations. Probability band widens with time, which indicates an increase of prediction uncertainty with time. The creep model uncertainty factor and the relative humidity appear as the most dominant factors with regard to the model output uncertainty.

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Comparison of Standardized Patient and Faculty Agreement in Evaluating Nursing Students' Assessment and Communication Skills (시뮬레이션기반 실습 시 간호학생의 간호사정 및 의사소통 기술에 대한 표준화 환자와 교수자 간의 평가 일치도)

  • Kim, Young Ju
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.24 no.3
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    • pp.189-199
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    • 2017
  • Purpose: This study was conducted to examine the level of agreement between a standardized patient (SP) and a faculty member in the evaluation of nursing students' assessment and communication skills. Methods: Participants were 51 third year nursing students in a simulation practice of 'nursing care for a patient admitted with chest pain'. Using a 30-item checklist and a 16-item communication tool, a SP and faculty member evaluated the students' assessment and communication skills during the simulation. Results: The average values for percent agreement and kappa statistic for nursing assessment between the two evaluators were 85.3% and .48 respectively. Twenty of thirty items evaluating assessment skill had above moderate agreement (${\geq}.41$) by kappa between the evaluators. Seven of sixteen items evaluating communication and interpersonal skills showed above fair agreement (${\geq}.40$) between the two evaluators, which was measured by intraclass correlation coefficient. Conclusion: The findings show that the evaluation of the SP was consistent with those of the faculty member to a moderate degree. Clear guidelines for evaluating criteria and optimal time and effort for SP training are necessary to increase the reliability of standardized patients as evaluators in simulation-based nursing education.

Photogrammetry Based on Standardized Clinical Photography using Cephalostat: Comparison with Anthropometric Analysis (머리고정기(Cephalostat)를 이용한 표준임상사진술에서 사진계측법: 인체계측법과의 비교)

  • Kwon, Hyuk Joon;Han, Ki Hwan;Kim, Jun Hyung;Son, Dae Gu
    • Archives of Plastic Surgery
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    • v.34 no.1
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    • pp.24-36
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    • 2007
  • Purpose: Direct anthropometry is an ideal method for preoperative planning and postoperative evaluation in plastic surgery, but it requires highly skilled specialty. Indirect anthropometry, especially photogrammetry, is an alternative method. In photogrammetry, standardized clinical photography is essential. Photogrammetry-based standardized clinical photography has several advantages over direct anthropometry. It is easier to measure and has less chance to make errors during measurement. Furthermore, it is possible to repeat measurements, and available for follow up study based on permanent custody. But, it is still different from actual measurement, and inherently less accurate than anthropometry. Methods: The authors revised the standardized clinical photography and then, carried out photogrammetry using Photoshop(Adobe, U.S.A.), and compared each data with those of anthropometry. The subjects were 50 males and 50 females, undergraduate medical students in twenties. Standard head position was obtained from the wire, fixed to cephalostat which indicates the Frankfort horizontal plane. All photographs were taken at the same situation such as fixed position of light, subject and camera, etc. Results: Total 96 measurements, based on 40 landmarks, consist of linear measurements, angular measurements and inclinations include 3 measurements in head, 22 in face, 15 in orbit, 28 in nose, 16 in lip and mouth, and 12 in ear. Conclusion: Normal photogrammetric data of face of Korean in twenties was obtained. Reliable photogrammetric measurements, not significantly different from anthropometric measurement statistically, accounted for 44 in 96 measurements(45.8%). Anthropometric values different from those of photogrammetric values were obtained by multiplying coefficient by photogrammetric value.

Reliability of Standardized Patients as Raters in Objective Structured Clinical Examination (객관 구조화 절차 기술 평가에서 채점자로서의 표준화환자의 신뢰도)

  • Son, Hee-Jeong;Moon, Joong-Bum;Lee, Hyang-Ah;Roh, Hye-Rin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.1
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    • pp.318-326
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    • 2011
  • The purpose of this study is to investigate whether standardized patient(SP) can be used as a reliable examiner in Objective Structured Clinical Examination(OSCE). 4 SPs and 4 faculties who have more than 2 years experience of OSCE scoring were selected. For 1 assignment 2 members of faculty and 2 SPs were designated as raters. SPs were educated for assessing 2 technical skills, male Foley catheter insertion and wound dressing, for 8 hours (4 hours / day, each topic). The definition, method, cautions and complications for each of procedural skills were covered in the education. Theoretical lectures, video learning, faculty demonstration and practical training on mannequins were employed. The 8 raters were standardized for an hour with simulated OSCE scoring using previous videos on the day before the OSCE. Each assessment was composed of 14 checklists and 1 global rate. The allotted time for each assignment was 5minutes and for evaluation time 2 minutes per student. The evaluation from the faculty and SPs were compared and analyzed with the GENOVA program. The overall generalizability coefficient (G coefficient) was 0.839 from two cases of OASTS. The reliability of the raters was high, 0.946. The inter-rater agreement between faculty group and SP group was 0.949 for checklist and 0.908 for global rating. Therefore SPs can play a role of raters in OSCE for procedural skills, if they are given the appropriate training.

Deep Learning-Based Computed Tomography Image Standardization to Improve Generalizability of Deep Learning-Based Hepatic Segmentation

  • Seul Bi Lee;Youngtaek Hong;Yeon Jin Cho;Dawun Jeong;Jina Lee;Soon Ho Yoon;Seunghyun Lee;Young Hun Choi;Jung-Eun Cheon
    • Korean Journal of Radiology
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    • v.24 no.4
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    • pp.294-304
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    • 2023
  • Objective: We aimed to investigate whether image standardization using deep learning-based computed tomography (CT) image conversion would improve the performance of deep learning-based automated hepatic segmentation across various reconstruction methods. Materials and Methods: We collected contrast-enhanced dual-energy CT of the abdomen that was obtained using various reconstruction methods, including filtered back projection, iterative reconstruction, optimum contrast, and monoenergetic images with 40, 60, and 80 keV. A deep learning based image conversion algorithm was developed to standardize the CT images using 142 CT examinations (128 for training and 14 for tuning). A separate set of 43 CT examinations from 42 patients (mean age, 10.1 years) was used as the test data. A commercial software program (MEDIP PRO v2.0.0.0, MEDICALIP Co. Ltd.) based on 2D U-NET was used to create liver segmentation masks with liver volume. The original 80 keV images were used as the ground truth. We used the paired t-test to compare the segmentation performance in the Dice similarity coefficient (DSC) and difference ratio of the liver volume relative to the ground truth volume before and after image standardization. The concordance correlation coefficient (CCC) was used to assess the agreement between the segmented liver volume and ground-truth volume. Results: The original CT images showed variable and poor segmentation performances. The standardized images achieved significantly higher DSCs for liver segmentation than the original images (DSC [original, 5.40%-91.27%] vs. [standardized, 93.16%-96.74%], all P < 0.001). The difference ratio of liver volume also decreased significantly after image conversion (original, 9.84%-91.37% vs. standardized, 1.99%-4.41%). In all protocols, CCCs improved after image conversion (original, -0.006-0.964 vs. standardized, 0.990-0.998). Conclusion: Deep learning-based CT image standardization can improve the performance of automated hepatic segmentation using CT images reconstructed using various methods. Deep learning-based CT image conversion may have the potential to improve the generalizability of the segmentation network.