• The Transactions of the Korean Institute of Electrical Engineers B
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• v.49 no.7
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• pp.488-493
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• 2000

In this paper, a predictive current control of 12-pulse parallel connected dual converter system without interphase reactors(IPR) is presented. Firstly, the characteristics of system without IPR are analyzed and compared with that of system with IPR. And the predictive current control of this system is discussed. Finally the validity of the presented system and the excellence of the predictive current control response is proved through the simulation results and experimental results.

• Journal of Korean Public Health Nursing
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• v.28 no.3
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• pp.495-508
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• 2014

Purpose: This study was conducted in order to evaluate the reliability, validity, sensitivity, and specificity of the Short Form of Bobath Memorial Hospital Fall Risk Assessment Scale (BMFRAS-SF). Methods: A validation study was conducted on 207 elderly patients aged over 65 who were admitted to Bobath Memorial Hospital. Fall risk scores of BMFRAS, composed of eight subscales (age, fall history, physical activity, consciousness level, communication, fall risk factors, underlying disease, and medications) were assessed from the electronic medical record. BMFRAS-SF was derived from eight subscales of the BMFRAS representing the significance between fallers and non-fallers (fall history, physical activity, fall risk factors, underlying disease, and medications). Internal consistency reliability and interrater reliability were assessed by Cronbach's alpha and kappa coefficient. Validity was assessed by Spearman correlation analysis, factor analysis. Sensitivity, specificity, positive predictive and negative predictive values, and a receiver-operating characteristic curve (ROC) were generated. Results: Fallers had significantly higher risk scores than non-fallers in fall history, physical activity, fall risk factors, underlying disease, and medication scales. The BMFRAS-SF demonstrated acceptable Cronbach's alpha (.706) and kappa coefficients of .95. The BMFRAS-SF subscales showed good convergent validity and construct validity. The BMFRAS-SF presented good sensitivity(86.7%), specificity(67.9%), positive predictive value(42.9%) and good negative predictive value(94.8%) at a cut-off score of 5. Areas under the ROC curves were .860 for the BMFRAS and .861 for the BMFRAS-SF. Conclusion: The BMFRAS-SF was proved to be reliable and valid. It could be used for time-saving assessment and evaluation of the high risks for falls in clinical practice settings.

• Journal of Korean Clinical Nursing Research
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• v.30 no.1
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• pp.35-44
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• 2024

Purpose: The purpose of this study is to compare the predictive validity of pressure injury risk assessment, Braden, Braden Q and Braden QD for pediatric patients. Methods: Prospective observational study included patients under the age of 19 who were hospitalized to general wards, intensive care units of a children's hospital. Characteristics related to pressure injury were collected, and predicted validity was compared by calculating the areas under the curve (AUC) of the Braden, Braden Q, and Braden QD scales. Results: A total of 689 patients were included in the study. A total of 13 (1.9%) patients had pressure injuries, and the number of pressure injuries was 17. Factors related to the occurrence of pressure injuries were 9 (52.9%) immobility-related and 8 (47.1%) medical device-related. The AUC for each scale was .91 (95% CI .89~.94) for Braden, .92 (95% CI .90~.95) for Braden Q, and .94(95% CI .92~.96) for Braden QD. The optimal cut-off points were identified as 16 for Braden (sensitivity=88.8%, specificity=86.4%), 17 for Braden Q(sensitivity=63.6%, specificity=94.9%), and 12 for Braden QD (sensitivity=94.4%, specificity=88.7%). Conclusion: The Braden QD scale demonstrated the highest predictive validity for pressure injuries in pediatric patients and is expected to be valuable tool in preventing pediatrics pressure injuries.

• Journal of Convergence for Information Technology
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• v.9 no.6
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• pp.175-182
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• 2019

This study was conducted to test the assessment validity and examine the cut-off scores for driving risk as a part of the Self-report Assessment Forecasting Elderly Driving Risk (SAFE-DR) development project. The 132 senior drivers were categorized as either risky of 58 or safe of 74 drivers through the Drivers 65 Plus. Based on this initial assessment, we analyzed the risk prediction cut-offs. Furthermore, we tested the construct, content, and predictive validity. The cut-off score for the prediction of driving risk was found to be 74.5 points. The positive predictive value was 88.6%, and the negative predictive value was 86.3% about the cut-off score, signifying an excellent level of discrimination. Convergent validity, nomological validity, and content validity were found to be appropriate. Therefore, this study confirms that SAFE-DR is an appropriate assessment that can be used to screen dangerous elderly drivers.

• Korean Journal of English Language and Linguistics
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• v.4 no.2
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• pp.229-252
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• 2004

The TOEIC has widely used to evaluate business English proficiency in Korea, but those who achieved high scores still often face difficulties in performing their duties in English at work. This implies that the test may not evaluate business English proficiency effectively enough. With an ultimate goal of proposing an effective way of assessing business English proficiency, therefore, his study analyzed the predictive validity of the TOEIC. A correlation analysis was conducted between TOEIC scores of 64 office workers of multinational companies and their working skills in English evaluated by themselves, and their colleagues and seniors. Its results illustrated a significant correlation between their listening and reading scores and their working skills measured by all the groups, but not between their scores and their working skills in speaking and writing. In addition, the study did a delphi study to identify working skills in English to be assessed in business English tests and a contents analysis of the TOEIC. The results suggest business English tests should be able to assess working skills by work types and more direct testing of working skills in speaking and writing is needed.

• Research in Community and Public Health Nursing
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• v.28 no.2
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• pp.206-215
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• 2017

Purpose: This study aimed to verify the predictive validity of Comprehensive Korean Frailty Instrument (CKFI) among older adults. Methods: A secondary analysis of data from a prospective cohort study was conducted. Frailty was determined in older adults (N=9,188) according to the data in 2008 and the effects of frailty on adverse outcomes (such as institutionalization and death) were evaluated according to the data in 2011. The Cardiovascular Health Study (CHS) index was used to compare with the predictive validity of CKFI. Results: The prevalence of frailty was 26.3%. With the CKFI, the frail group had a higher risk of negative health outcomes compared to the robust and pre-frail groups after three years. The two of the highest risks identified using the CKFI and CHS index were institutionalization (5.522 times higher) and mortality (3.210 times higher). For both instruments, the survival analysis revealed that the risk of death increased as the degree of frailty increased. Conclusion: The CKFI consisting of self-report items and multidimensional aspects of frailty can be used as a simple instrument for assessing the frailty of older adults residing in a local community in Korea.

• Clinical and Experimental Reproductive Medicine
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• v.20 no.1
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• pp.1-7
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• 1993

The present study was designed to test the validity of the semen analysis(S/A) and the sperm penetration assay(SPA) as a prognostic indicator of male fertility in 123 patients undergoing in vitro fertilization(IVF). We attempted to correlate the traditional semen parameters or the extent of sperm penetration in SPA with the results of human IVF rate or cleavage rate. Poor correlation was found between the results of S/A and human IVF rate(sensitivity, 80.6% ;specificity, 46.7%; positive predictive value, 91.6%;negative predictive value, 25%). Conversely, good correlation was found between the results of SPA and human IVF rate(sensitivity, 100% ; specificity, 80% ;positive predictive value, 97.3% ;negative predictive value, 100%). Our results corroborate the conclusion that SPA can be a valuable tool as a prognostic indicator of male fertilizing ability.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.22 no.3
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• pp.169-181
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• 2011

Objectives: The Child Report of Post-traumatic Symptoms (CROPS) and the Parent Report of Post-traumatic Symptoms (PROPS) are screening measures for post-traumatic symptoms in children. The present study aimed to investigate the reliability and validity of the Korean versions of the CROPS and the PROPS. Methods: The Korean versions of the CROPS and the PROPS were administered to a sample of 304 children aged 6 to 15 years old. The internal reliability, test-retest reliability, factorial validity, predictive validity and concurrent validity were evaluated. Results: The reliability of the CROPS and the PROPS was shown to have excellent internal consistency and test-retest correlation. The single factor structure of the PROPS was good and that of the CROPS was borderline acceptable according to confirmatory factor analysis. Other validity measures such as the predictive validity and concurrent validity were also shown to be satisfactory. Conclusion: This study demonstrated that the Korean versions of the CROPS and the PROPS were reliable measures with satisfactory psychometric qualities. Because it takes less than 5 minutes to fill out the CROPS and the PROPS, respectively they can be quick and easy screening scales for assessing post-traumatic symptoms in Korean children.

• Nutrition Research and Practice
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• v.12 no.4
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• pp.283-290
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• 2018

BACKGROUND/OBJECTIVES: Indirect calorimetry is the gold-standard method for the measurement of resting energy expenditure. However, this method is time consuming, expensive, and requires highly trained personnel. To overcome these limitations, various predictive equations have been developed. The objective of this study was to assess the validity of predictive equations for resting energy expenditure (REE) in Korean non-obese adults. SUBJECTS/METHODS: The present study involved 109 participants (54 men and 55 women) aged between 20 and 64 years. The REE was measured by indirect calorimetry. Nineteen REE equations were evaluated for validity, by comparing predicted and measured REE results. Predictive equation accuracy was assessed by determining percent bias, root mean squared prediction error (RMSE), and percentage of accurate predictions. RESULTS: The measured REE was significantly higher in men than in women (P < 0.001), but the difference was not significant after adjusting for body weight (P > 0.05). The equation developed in this study had an accuracy rate of 71%, a bias of 0%, and an RMSE of 155 kcal/day. Among published equations, the $FAO_{weight}$ equation gave the highest accuracy rate (70%), along with a bias of -4.4% and an RMSE of 184 kcal/day. CONCLUSIONS: The newly developed equation provided the best accuracy in predicting REE for Korean non-obese adults. Among the previously published equations, the $FAO_{weight}$ equation showed the highest overall accuracy. Regardless, at an individual level, the equations could lead to inaccuracies in a considerable number of subjects.

• Proceedings of the KIEE Conference
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• 2008.11a
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• pp.65-67
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• 2008

A new pulse width modulation method based on predictive current control strategy is proposed to modulate matrix converters. The predictive current controller utilizes a discrete-time model to predict the future values of output currents and generates proper duty-ratios ta minimize the output current errors. The proposed method uses continuous carrier and establishes a predictive current controller to predetermine duty ratio signal for directly generating gating signals an thus is named "predictive current control PWM(PCCPWM)". The modulation algorithm nd the required equations are derived by using average concept over one switching period. Thus it can be easily extended to other matrix converter topologies, especially with neutral connections, such as sing le-phase ad two-phase matrix converters. The feasibility and validity of the proposed strategy are verified by computer simulation and experimental results.