• Journal of Magnetics
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• v.22 no.1
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• pp.133-140
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• 2017

Split magnetic fluid sealing is a combination of magnetic fluid rotary and plane sealing. Using the theory of equivalent magnetic circuit design as basis, the author theorized the pressure resistance performance of magnetic fluid plane sealing. To determine the pressure resistance of magnetic fluid plane sealing, the author adopted the method of finite element analysis to calculate the magnetic field intensity in the gap between plane sealing structures. The author also analyzed the effect of different sealing gaps, as well as different ratios between the sealing gap and tooth and solt width, on the sealing performance of split magnetic fluid. Results showed that the wider the sealing gap, the lower the sealing performance. Tooth width strongly affects sealing performance; the sealing performance is best when the ratio between tooth width and sealing gap is 2, whereas the sealing performance is poor when the ratio is over 8. The sealing performance is best when the ratio between the solt width and sealing gap is 4, indicating a slight effect on sealing performance when the ratio between the solt width and sealing gap is higher. Theoretical analysis and simulation results provide reference for the performance evaluation of different sealing equipment and estimation of critical pressure at interface failure.

• International Journal of Highway Engineering
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• v.18 no.1
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• pp.91-97
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• 2016

PURPOSES : The objective of this paper is to develop a pavement performance model based on the Bayesian algorithm, and compare the measured and predicted performance data. METHODS : In this paper, several pavement types such as SMA (stone mastic asphalt), PSMA (polymer-modified stone mastic asphalt), PMA (polymer-modified asphalt), SBS (styrene-butadiene-styrene) modified asphalt, and DGA (dense-graded asphalt) are modeled in terms of the performance evaluation of pavement structures, using the Bayesian algorithm. RESULTS : From case studies related to the performance model development, the statistical parameters of the mean value and standard deviation can be obtained through the Bayesian algorithm, using the initial performance data of two different pavement cases. Furthermore, an accurate performance model can be developed, based on the comparison between the measured and predicted performance data. CONCLUSIONS : Based on the results of the case studies, it is concluded that the determined coefficients of the nonlinear performance models can be used to accurately predict the long-term performance behaviors of DGA and modified asphalt concrete pavements. In addition, the developed models were evaluated through comparison studies between the initial measurement and prediction data, as well as between the final measurement and prediction data. In the model development, the initial measured data were used.

• Journal of Distribution Science
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• v.19 no.10
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• pp.35-41
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• 2021

Purpose: Research on the development of distribution channels and the strategy will help businesses develop competitiveness in the market. At the same time, the excellent effect of distribution channels and the outstanding implementation of business strategies will help optimize firm performance. Therefore, this study helps to evaluate the influence of distribution channels, and strategy factors on the performance of FDI enterprises in Vietnam. Research design, data, and methodology: Research using quantitative method with PLS-SEM model based on 210 samples using Smart-PLS3. software. The survey subjects are corporate managers who understand the strategies, distribution channels, and performance in Vietnamese FDI enterprises. Results: The analysis results show that strategy factors have a positive effect on firm performance, and distribution channel also has a positive impact on firm performance. This result also indicates that distribution channels activity as an intermediary between strategy and firm performance. Conclusion: The study also gives some policy implications on strategy and distribution channels to improve firm performance. The strategic implementation of finance, human resources, risk, innovation, and diversification of distribution channels are implications for improving firm performance in FDI enterprises. In addition, the research has contributed to the relationship between the distribution channels and firm performance.

• The Journal of Asian Finance, Economics and Business
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• v.10 no.1
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• pp.209-221
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• 2023

A significant body of prior research on performance management systems (PMSs) either explains the components and the design of the systems or investigates the link between particular system/s and organizational functions, capabilities, or performance. In contrast, this study investigates the comprehensive use of PMSs and relates them to corporate financial and non-financial performance. Further, this study examines whether the association between PMSs and performance varies between industries or is moderated by the size of the company. Data was collected using a questionnaire that was sent to companies from different industries operating in Riyadh province, where the most important businesses in Saudi Arabia are located. A total of 152 usable responses were received. The results of this study revealed that companies use a variety of PMSs at a balanced level. The extent of each category of PMS use is associated with the extent of other PMS categories' use. However, the larger the company, the more PMSs it uses. Importantly, the results showed a positive and significant association between PMSs' extent of use and both financial and non-financial performance. This association was minimally moderated by the company size and industry for specific categories of PMSs and performance.

• The Transactions of the Korea Information Processing Society
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• v.6 no.11
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• pp.3011-3019
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• 1999

Denial of service is about knocking off services, without permission for example through crashing the whole system. This kind of attacks are easy to launch and it is hard to protect a system against them. The basic problem is that Unix assumes that users on the system or on other systems will be well behaved. This paper analyses system-based inside denial of services attack(DoS) and system metric for performance of each machine provided. And formalize the conclusions results in ways that clearly expose the performance impact of those observations. So, we present new approach. It is detecting DoS attack using performance signature for system and program behavior. We present new approach. It is detecting DoS attack using performance signature for system and program behavior. We believe that metric will be to guide to automated development of a program to detect the attack. As a results, we propose the AIDPS(Architecture for Intrusion Detection using Performance Signature) model to detect DoS attack using performance signature.

• The Korean Journal of Health Service Management
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• v.11 no.1
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• pp.11-25
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• 2017

Objectives : The purpose of this study is to analyze the differences in financial performance, productivity, and patient care performance between metropolitan and non - metropolitan hospitals and examine the factors affecting profitability of both groups. Methods : The survey period consisted of three years of data that can identify the financial performance of the hospital. The survey subjects were selected from 58 metropolitan hospitals, 87 non - metropolitan hospitals and 147 hospitals. Results : There was a significant difference in stability, activity, cost index, productivity, and patient care performance between the metropolitan and non - metropolitan hospitals, and metropolitan hospitals showed a relatively higher ratio. Conclusions : In the metropolitan and non-metropolitan hospitals, the variables of productivity and cost index increase the profitability. However, if the factors with less influence on the results of the study are applied to the variables of various situations, it may have a great influence on the profitability increase.

• Phonetics and Speech Sciences
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• v.10 no.1
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• pp.33-38
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• 2018

Although deep neural network-based acoustic models have greatly improved the performance of automatic speech recognition (ASR), reverberation still degrades the performance of distant speech recognition in indoor environments. In this paper, we adopt the DenseNet, which has shown great performance results in image classification tasks, to improve the performance of reverberant speech recognition. The DenseNet enables the deep convolutional neural network (CNN) to be effectively trained by concatenating feature maps in each convolutional layer. In addition, we extend the concept of multi-resolution CNN to multi-resolution DenseNet for robust speech recognition in reverberant environments. We evaluate the performance of reverberant speech recognition on the single-channel ASR task in reverberant voice enhancement and recognition benchmark (REVERB) challenge 2014. According to the experimental results, the DenseNet-based acoustic models show better performance than do the conventional CNN-based ones, and the multi-resolution DenseNet provides additional performance improvement.

• Korean System Dynamics Review
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• v.8 no.1
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• pp.211-227
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• 2007

Like the saying "You can't manage what you can't measure," performance measurement is considered as one of the most important management activities for the organizations in either private or public sector. Performance measurement, however, has thus far relied too much on financial statements. Realizing the importance of a more scientific and comprehensive performance measurement, many organizations have adopted several different systems in order to objectively estimate their balanced performance results. The Balanced Scorecard (BSC) has become a popular means to measure performance. But the BSC has also received some criticisms. In this paper four limitations in the use of the BSC are discussed : BSCs focus on unidirectional causality, are unable to distinguish delays between actions and their impacts on performance, integrate insufficiently strategy with operational measures, and lead to internal biases. We propose a system dynamics approach with causal loop diagram(CLD) to develop a Dynamic BSC in order to overcome these limitations. The results suggest that developing a BSC with system dynamics is a promising approach to supplement existing BSC frameworks.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.572-575
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• 2008

Flow-field design has much influence over the performance of proton exchange membrane fuel cell (PEMFC) because it affects the pressure magnitude and distribution of the reactant gases. To obtain the pressure magnitude and distribution of reactant gases in four kinds of flow-field designs without additional measurement equipment, computational fluid dynamics (CFD) analysis was performed. After the CFD analysis, the performance values of PEMFC according to the flow-field configurations were measured via a single cell test. As expected, the pressure differences due to different flow-field configurations were related to the PEMFC performance because the actual performance results showed the same tendency as the results of the CFD analysis. A large pressure drop resulted in high PEMFC performance. So, the single serpentine configuration gave the highest performance. On the other hand, the parallel flow-field configuration gave the lowest performance because the pressure difference between inlet and outlet was the lowest.

• Journal of the Korea Society for Simulation
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• v.3 no.2
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• pp.49-56
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• 1994

Performance measurement and analysis for computer systems has been studied for a long time. However, little attention has been focused on how to distribute a given budget to each part of a computer system for enhancing system performance maximally. In traditional approaches, performance enhancement is achieved by identifying a dominant system bottleneck and enhancing the bottleneck's performance. These approaches, however, often bring problems since the removal of a bottleneck may result in other bottlenecks. This paper proposes an approximated method for such budget distribution problem. For budget distribution, a critical set is defined. The set contains the servers of which performance changes affect the overall system performance significantly. Then, the given budget is distributed properly to every server in the critical set. To verify the proposed method, two benchmark experiments are carried out I SLAM environments. The experimental results show that the proposed method provides better results than the traditional method does in many cases.