• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.05a
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• pp.27-31
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• 2003

Underwater acoustic navigation systems are classified into three systems: ultra-short baseline (USBL), short baseline (SBL), and long baseline (LBL). Because the USBL system estimates the angle of a submersible, the estimation error becomes large if the submersible is far from the USBL transducer array mounted under a support vessel. SBL and LBL systems estimate submersible's location more accurately because they have wider distribution of measuring sensors. Especially LBL systems are widely used as a navigation system for deep ocean applications. Although it is most accurate system it still has estimation errors because of noise, measurement error, refraction and multi-path of acoustic signal, or wrong information of the distributed transponders. In this paper the estimation error of the LBL system are analyzed from a point of sensitivity. It is assumed that the error exists only in the distance between a submersible and the transponders. For this purpose sensitivity of the estimated position with respect to relative distances between them is analyzed. The result says that estimation error is small if the submersible is close to transponders but not near the ocean bottom.

• Journal of Electrical Engineering and Technology
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• v.12 no.2
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• pp.541-548
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• 2017

An increasing concern is paid to short-term voltage stability with the growth of penetration of induction motor loads. Reactive power reserve(RPR) of power system is critical to improve voltage stability. A definition of short-term voltage stability-related RPR(SVRPR) is proposed. Generators vary their contributions to voltage stability with their location and system condition, etc. Voltage support coefficient based on the second-order trace sensitivity method is proposed to evaluate SVRPR's contribution to short-term voltage stability. The evaluation method can account for the generator's reactive support in transient process and the contingency severity. Then an optimization model to improve short-term voltage stability is built. To deal with multiple contingencies, contingency weight taking into account both its probability and severity is proposed. The optimization problem is solved by primal dual interior point method. Testing on IEEE_39 bus system, it is indicated that the method proposed is effective. Short-term voltage stability is improved significantly by the way of SVRPR optimization. Hence, the approach can be used to prevent the happening of voltage collapse during system's contingency.

• Journal of Electrical Engineering and Technology
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• v.10 no.4
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• pp.1899-1909
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• 2015

Glaucoma is one of the most common causes of blindness which is caused by increase of fluid pressure in the eye which damages the optic nerve and eventually causing vision loss. An automated technique to diagnose glaucoma disease can reduce the physicians’ effort in screening of Glaucoma in a person through the fundal retinal images. In this paper, optimal hyper analytic wavelet transform for Glaucoma detection technique from fundal retinal images is proposed. The optimal coefficients for transformation process are found out using the hybrid GSO-Cuckoo search algorithm. This technique consists of pre-processing module, optimal transformation module, feature extraction module and classification module. The implementation is carried out with MATLAB and the evaluation metrics employed are accuracy, sensitivity and specificity. Comparative analysis is carried out by comparing the hybrid GSO with the conventional GSO. The results reported in our paper show that the proposed technique has performed well and has achieved good evaluation metric values. Two 10- fold cross validated test runs are performed, yielding an average fitness of 91.13% and 96.2% accuracy with CGD-BPN (Conjugate Gradient Descent- Back Propagation Network) and Support Vector Machines (SVM) respectively. The techniques also gives high sensitivity and specificity values. The attained high evaluation metric values show the efficiency of detecting Glaucoma by the proposed technique.

• Journal of Korean Academy of Nursing
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• v.34 no.3
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• pp.504-514
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• 2004

Purpose: The purpose of this study is to identify the influencing factors of mother-infant attachment and construct a descriptive model that explains mother-infant attachment during the early postpartum period. Method: The hypothetical model of this study consisted of 8 variables with 23 constructed paths. The subjects of this study were 152 postpartum women. Data was analyzed to test the hypothetical model using covariance structure analysis. Result: The final model which is modified from the hypothetical model improved to Chi-Square 41.92, GFI .95, AGFI .89, RMSR .02, RMSEA .06, NFI .94, and NNFI .95. Mother-infant attachment during the early postpartum period was proven to be influenced directly by neonatal perception, maternal sensitivity, and maternal-fetal attachment and also indirectly by social support, maternal-fetal attachment and maternal identity. These variables accounted for 32% of the variance of the mother-infant attachment during the early postpartum period. Conclusion: It is necessary that the nurses provide postpartum women with an intervention using social support for improving maternal identity and alleviating maternal role strain. It can be helpful to improve maternal sensitivity and in the end it will facilitate the mother-infant attachment during postpartum period.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.97-102
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• 2013

Objective: The aim of this study was to develop an automated computer-aided diagnostic system for diagnosis of thyroid cancer pattern in fine needle aspiration cytology (FNAC) microscopic images with high degree of sensitivity and specificity using statistical texture features and a Support Vector Machine classifier (SVM). Materials and Methods: A training set of 40 benign and 40 malignant FNAC images and a testing set of 10 benign and 20 malignant FNAC images were used to perform the diagnosis of thyroid cancer. Initially, segmentation of region of interest (ROI) was performed by region-based morphology segmentation. The developed diagnostic system utilized statistical texture features derived from the segmented images using a Gabor filter bank at various wavelengths and angles. Finally, the SVM was used as a machine learning algorithm to identify benign and malignant states of thyroid nodules. Results: The SVMachieved a diagnostic accuracy of 96.7% with sensitivity and specificity of 95% and 100%, respectively, at a wavelength of 4 and an angle of 45. Conclusion: The results show that the diagnosis of thyroid cancer in FNAC images can be effectively performed using statistical texture information derived with Gabor filters in association with an SVM.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.1
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• pp.133-140
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• 2011

For both customers and companies, it is very important to analyze online customer reviews, which consist of small documents that include opinions or experiences about products or services, because the customers can get good informations and the companies can establish good marketing strategies. In this paper, we propose the association model for the opinion mining which can analyze customer opinions posted on web. The association model is to modify the association rules mining model in data mining in order to apply efficiently and effectively the association mining techniques to the opinion mining. We designed and implemented the opinion mining systems based on the modified association model and the grouping idea which would enable it to generate significant rules more.

• Safety and Health at Work
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• v.10 no.3
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• pp.314-320
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• 2019

Background: Sitting posture may be related to risk factors, including inadequate weight-bearing support, particularly when maintained for long periods. Considering that body weight is loaded in a closed support system composed of the seat, backrest, floor and working surface, the aims of the present study were to describe the development of an ergonomic sitting workstation to continuously record weight-bearing at the seat, chair, backrest, work surface, and floor and to test its measurement properties: reproducibility, criterion-related validity, and sensitivity. Methods: Rigid bodies (1 to 30 kg) and participant weights were recorded to evaluate the workstation measurement properties. Results: Rigid body tests showed variation values less than 0.050 kg on reproducibility test and errors below 5% of measured value on criterion validity tests. Participant tests showed no statistically significant differences between repeated measures ($p{\geq}0.40$), errors were less than 2% of participant weights an sensitivity presented statistically significant changes (p = 0.007). Conclusion: The sitting workstation proposed showed to be reliable, valid and sensitive for use in future ergonomic studies to evaluate the sitting posture.

• The Journal of Korean Academic Society of Nursing Education
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• v.29 no.2
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• pp.148-160
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• 2023

Purpose: The purpose of this study was to construct and test a structural model of nursing students' performing communication skills. Methods: The data collection was conducted from October 13 to October 20, 2020. The participants were 286 students from nursing colleges located in three cities. The data analysis method was a covariance structure analysis with using IBM SPSS statistics version 23.0 and AMOS 21.0 statistical programs. Results: The hypothetical model showed a proper fit with the data: root mean square error of approximation=.08, standardized root mean square residual=.06, adjusted goodness of fit=.85, normed fit index=.91, and comparative fit index=.94. The model fit indices were normed to fit index=2.96. Statistically significant explanatory variables for the performing communication skills of nursing students were peer support, emotional intelligence, ethical sensitivity, and communication self-efficacy. The variables accounted for 66.1% of the performing communication skills of nursing students. Conclusion: Based on the above results, it appears necessary to develop strategies for improving the performing communication skills of nursing students, and having positive effects on health outcomes of the subjects by considering the variables of peer support, emotional intelligence, ethical sensitivity, and communication self-efficacy. Such strategies could potentially have positive effects on the health outcomes of the patients.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.6
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• pp.95-114
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• 2020

This paper, a meta-analysis of the effect of the start-up support policy on the start-up performance was conducted to examine the effect of the start-up support policy on the start-up performance of beneficiary companies and to provide theoretical and practical implications to support organizations and practitioners. To this end, 35 papers containing the correlation coefficient, which is a positive statistical value, were selected from the previous studies in academic journals and dissertations published in Korea from 2007 to 2020. In the preceding study of the start-up support policy, the independent variables include funding, education support, facility/equipment support, network support, mentoring support, consulting support, marketing support, management support, technical support, manpower support, and finance as a dependent variable. The effect size of the impact on aptitude and non-financial performance was reviewed. The pattern of the effect size was presented as a forest plot for easy visual understanding, and outliers were verified through sensitivity analysis for small-study-effect data with publication convenience. As a result of analyzing the effect size of the government-supported policy, it was verified that the effect size was generally medium or higher, affecting the entrepreneurial performance. Among the independent variables, the factor that has the greatest effect on startup performance is manpower support, followed by technical support, marketing support, management support, facility/equipment support, education support, mentoring support, funding, network support, and consulting support. It was analyzed that the effect size was large in order. As the 「Small and Medium Business Startup Support Act」 was recently reorganized from the manufacturing industry to digital transformation and smartization on October 8, 2020, the start-up support policy should consider the start-up stage and verify the priorities to organize the budget.

• Journal of Korea Entertainment Industry Association
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• v.15 no.6
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• pp.105-113
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• 2021

The purpose of this study was to examine the correlation among Cultural empathy, Multicultural sensitivity, and Cultural competence of Nursing Students. Data were collected using questionnaires from 191 nursing students who were in 2rd and 4^th year of the college in D city. The collected data was analyzed using SPSS version 22.0. The mean score of Cultural empathy, Multicultural sensitivity and Cultural competence in nursing students were 3.72±0.23, 3.14±0.27, and 3.10±0.32 respectively. Cultural empathy showed significant positive correlations with Multicultural sensitivity(r=.63, p<.001), and Cultural competence(r=.57, p<.001). Multicultural sensitivity was also positively correlated with Cultural competence(r=.41, p<.001). The result of this study suggest that multicultural nursing education is necessary for students to develop and support programs that can provide diverse cultural experiences.