• Journal of the Korean Society of Radiology
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• v.81 no.2
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• pp.379-394
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• 2020

Purpose To design a scoring system to predict malignancy of additional MRI-detected lesions in breast cancer patients. Materials and Methods Eighty-six lesions (64 benign and 22 malignant) detected on preoperative MRI of 68 breast cancer patients were retrospectively included. The clinico-radiologic features were correlated with the histopathologic results using the Student's t-test, Fisher's exact test, and logistic regression analysis. The scoring system was designed based on the significant predictive features of malignancy, and its diagnostic performance was compared with that of the Breast Imaging-Reporting and Data System (BI-RADS) category. Results Lesion size ≥ 8 mm (p < 0.001), location in the same quadrant as the primary cancer (p = 0.005), delayed plateau kinetics (p = 0.010), T2 isointense (p = 0.034) and hypointense (p = 0.024) signals, and irregular mass shape (p = 0.028) were associated with malignancy. In comparison with the BI-RADS category, the scoring system based on these features with suspicious non-mass internal enhancement increased the diagnostic performance (area under the receiver operating characteristic curve: 0.918 vs. 0.727) and detected three false-negative cases. With this scoring system, 22 second-look ultrasound examinations (22/66, 33.3%) could have been avoided. Conclusion The scoring system based on the lesion size, location relative to the primary cancer, delayed kinetic features, T2 signal intensity, mass shape, and non-mass internal enhancement can provide a more accurate approach to evaluate MRI-detected lesions in breast cancer patients.

• The KIPS Transactions:PartA
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• v.14A no.1 s.105
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• pp.63-72
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• 2007

This paper introduces a load-balancing algorithm focusing on distributing web requests evenly into the web cluster servers. The load-balancing algorithms based on conventional periodic load-information update mechanism are not suitable for dynamic page applications, which are common in Cyber Foraging services, due to the problems caused by periodic synchronized load-information updating and the difficulties of work load estimation caused by embedded executing scripts of dynamic pages. Update-on-Finish algorithm solves this problem by using non-periodic load-update mechanism, and the web switch knows the servers' real load information only after their reporting and then distributes new loads according to the new load-information table, however it results in much communication overhead. Our proposed mechanism improve update-on-finish algorithm by using K-Percents-Finish mechanism and thus largely reduce the communication overhead. Furthermore, we consider the different capabilities of servers with a threshold Ti value and propose a load-balancing algorithm for servers with various capabilities. Simulation results show that the proposed K-Percents-Finish Reporting mechanism can at least reduce 50% communication overhead than update-on-finish approach while sustaining better load balancing performance than periodic mechanisms in related work.

• Journal of Preventive Medicine and Public Health
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• v.53 no.6
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• pp.447-454
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• 2020

Objectives: The aim of the present study was to investigate the relationships among hospital safety climate, patient safety climate, and safety outcomes among nurses. Methods: In the current cross-sectional study, the occupational safety climate, patient safety climate, and safety performance of nurses were measured using several questionnaires. Structural equation modeling was applied to test the relationships among occupational safety climate, patient safety climate, and safety performance. Results: A total of 211 nurses participated in this study. Over half of them were female (57.0%). The age of the participants tended to be between 20 years and 30 years old (55.5%), and slightly more than half had less than 5 years of work experience (51.5%). The maximum and minimum scores of occupational safety climate dimensions were found for reporting of errors and cumulative fatigue, respectively. Among the dimensions of patient safety climate, non-punitive response to errors had the highest mean score, and manager expectations and actions promoting patient safety had the lowest mean score. The correlation coefficient for the relationship between occupational safety climate and patient safety climate was 0.63 (p<0.05). Occupational safety climate and patient safety climate also showed significant correlations with safety performance. Conclusions: Close correlations were found among occupational safety climate, patient safety climate, and nurses' safety performance. Therefore, improving both the occupational and patient safety climate can improve nurses' safety performance, consequently decreasing occupational and patient-related adverse outcomes in healthcare units.

• Journal of Advanced Navigation Technology
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• v.14 no.2
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• pp.266-271
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• 2010

In this paper, we chose IOPS(input output operation per second) and MB/s as a performance standard, and we developed the evaluation standard for the storage performance. Since there is no vendor-neutral evaluation criteria for storage performance, it is difficult to evaluate storage performance and design the storage resource's sizing. We proposed block size for measurement of the storage's IOPS for OLTP(online transaction processing) application to 4KB, 8KB and 16KB and read/write rate of it to 7:3. On the other hand, we proposed block size for measurement of the storage's IOPS for backup, VOD, Large file processing) to 64KB, 256KB and 1024KB and read/write rates of it to 7:3 and 1:0. Finally, we proposed the Vdvench BMT tool, which is independent on platform. We also developed the result reporting tool for developed evaluation criteria.

• Transactions of the KSME C: Technology and Education
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• v.4 no.1
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• pp.11-18
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• 2016

Under the Renewable Heat Obligation (RHO) public buildings in the Republic of Korea larger than $10,000m^2$ must achieve an 11% overall reduction to thermal energy consumption. Well intended solutions have been proposed. However, not all option is evaluated on the same basis, potentially resulting in incomplete or sub-optimal solutions. What's more once projects are implemented, there are inconsistencies in the methods used to measure and evaluate operating performance of the post-retrofit case. The RETScreen decision tools and methodology can be used by decision makers, policy developers, architects, engineers and community leaders to evaluate and select the most effective solutions for Korea's RHO needs.

• Journal of Korean Clinical Nursing Research
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• v.19 no.1
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• pp.152-167
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• 2013

Purpose: The purpose of this study was to develop a website-based patient safety culture promotion program that could be implemented by nurses in real work scenarios. Methods: This study was a methodological study. A patient safety culture promotion program, called 'Safe Culture, Save Patients' was developed, based on structuration theory and performance engineering approaches. Results: This program was delivered in the form of a website containing contents about changes in the work environment, information about accidents and the improvement process details, as well as a program for motivation. The program was tested about the validity on contents and usability - a panel of 14 experts confirmed its validity using the contents validity index (CVI), with a resulting S-CVI of .980. Usability was evaluated by 11 nurses, which allowed finalize the program. Conclusion: The 'Safe Culture, Save Patients' program was a valid program that could be applied in clinical practice immediately. The results of this study warrant further studies to evaluate the effects of this patient safety culture promotion program.

• Journal of electromagnetic engineering and science
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• v.10 no.3
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• pp.190-198
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• 2010

This paper evaluates the performance of two methods of spectrum sensing: the linear combining method and the selection combining method which is based on maximum SNR of sensing channel. We proposed a rule for global detection for the purpose of combating hidden terminal problems in spectrum sensing. Our analysis considers a situation when sensing channels experience the non-identically, independently distributed(n.i.d) Rayleigh fading. The average probabilities of global detection in these methods are derived and compared. In the scope of this paper, the reporting channels are assumed to be the AWGN channel with invariant and identical gain during the system's operation.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1994.04a
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• pp.344-354
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• 1994

In the development of executive information systems (EIS) the selection of an appropriate software package as a system building tool is regarded as a key technology. This paper attempts to shed some light on the evolving field of EIS software packages and provides a helpful Guideline for selecting the most suitable product by addressing significant considerations. A framework is presented that includes a six-step evaluation process: need analysis, team building, vendor survey, identification of decision criteria, and building an evaluation model and its verification. The major evaluation criteria of the full-featured software include: special functionality, reporting, graphics. decision support capability user friendliness, general functionality physical requirements, communication linkage, vendor support, cost related factors, performance, and documentation capability. An illustrative model using the analytic hierarchy process (AHP) method is also discussed to prove the appropriateness of our approach.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.269-276
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• 2004

This study tried to figure out the framework of safety culture in railway industry to analyze root causes of railway incidents and accidents at Korean National Railway. Through the literature survey, authors found some critical dimensions common to railway safety culture such as employees' belief in the managers' management weight on safety and productivity, recognition of safety importance, risk taking attitude, practice of safety meeting before and after doing work, communication between management and employees and among drivers, traffic managers and infrastructure maintenance workers, safety reporting practice, safety and performance appraisal, effectiveness of safety audit, safety training, work place arrangement, incidents and accidents investigation, and safety knowledge management.

• Journal of Hydrogen and New Energy
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• v.23 no.1
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• pp.49-55
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• 2012

Hydrogen isotopes accountancy and storage are important functions in a nuclear fusion fuel cycle. The hydrogen isotopes are safely stored in metal hydride beds. The tritium inventory of the bed is determined from the decay heat of tritium. The decay heat is measured by circulating helium through the metal hydride bed and measuring the resultant temperature increase of the helium flow. We are reporting our preliminary experimental results on the hydrogen isotopes accountancy and storage performance in a metal hydride bed.