• Journal of Communications and Networks
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• v.18 no.3
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• pp.351-363
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• 2016

This paper investigates the performance of interference-limited two-way transmission protocols in the Rayleigh fading channels. New lower bound of outage probability and approximate expression of bit error rate (BER) for three-phase two-way relaying (3P-TWR) protocol are derived in closed-form. These expressions are valid for arbitrary signal-to-noise ratio values, numbers of co-channel interferers and amajority of modulation formats employed in the practical system. Then a comparative study is developed for the performance of three two-way transmission protocols, i.e., direct transmission (DT) protocol, two-phase two-way relaying (2P-TWR) protocol and 3P-TWR protocol based on the asymptotic expressions of outage probability and BER. On the basis of the theoretical results, the thresholds on the strength (variance) of direct channel and target rate for the relative performance of different protocols are obtained and the effect of interferences at the terminal and relay on the relative performance is analyzed. The results present key insights on how to choose proper two-way transmission protocol with the knowledge of fading channels, required date rate and modulation format to optimize the system performance in the practical interference-limited scenarios. Simulation results are presented to validate the theoretical analysis.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.27-34
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• 2008

As for the performance related to a fire safety like fire resistance efficiency and evacuation safety etc. It is the ain of this study to investigate the comparative survey of expression methods for fire safety performance in Korea and Japan. The results of this study that there are so difference between Japan and Korea and suggests that the necessity for converting the fire risk calculated by an advanced technique into a simple expression.

• Journal of information and communication convergence engineering
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• v.9 no.5
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• pp.551-555
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• 2011

Optical packet switching is a promising technology, which can integrate both data and optical network. In this paper, we present a comparative study of various traffic arrival approaches in WDM packet switches. The comparison is made based on packet loss rate and average delay under uniform and self-similar Pareto traffic. Computer simulations are performed in order to obtain the switch performance metrics. Study shows that burstiness of data traffic has a strong negative impact in the performance of WDM packet switches.

• Communications for Statistical Applications and Methods
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• v.19 no.6
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• pp.885-898
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• 2012

In this paper, we consider Bayesian approaches to partially linear models, in which a regression function is represented by a semiparametric additive form of a parametric linear regression function and a nonparametric regression function. We make a comparative study on the performance of widely used Bayesian partially linear models in terms of empirical analysis. Specifically, we deal with three Bayesian methods to estimate the nonparametric regression function, one method using Fourier series representation, the other method based on Gaussian process regression approach, and the third method based on the smoothness of the function and differencing. We compare the numerical performance of three methods by the root mean squared error(RMSE). For empirical analysis, we consider synthetic data with simulation studies and real data application by fitting each of them with three Bayesian methods and comparing the RMSEs.

• Journal of the Semiconductor & Display Technology
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• v.12 no.3
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• pp.59-64
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• 2013

Accurate and robust image registration is important task in many applications such as image retrieval and computer vision. To perform the image registration, essential required steps are needed in the process: feature detection, extraction, matching, and reconstruction of image. In the process of these function, feature extraction not only plays a key role, but also have a big effect on its performance. There are two representative algorithms for extracting image features, which are scale invariant feature transform (SIFT) and speeded up robust feature (SURF). In this paper, we present and evaluate two methods, focusing on comparative analysis of the performance. Experiments for accurate and robust feature detection are shown on various environments such like scale changes, rotation and affine transformation. Experimental trials revealed that SURF algorithm exhibited a significant result in both extracting feature points and matching time, compared to SIFT method.

• Journal of Convergence for Information Technology
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• v.10 no.4
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• pp.55-64
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• 2020

This research empirically explores the relationship between types of performance information use, decision making behaviors and performance of government organizations. We measured two types of using performance information, relevance of performance index, variety of performance information, and levels of manager intervention by surveying performance managers of each government ministry or agency and also measured performance by using performance reports. The results of fuzzy-set qualitative comparative analysis suggest that hard use and soft use have impact on performance by combining with characteristics of performance information and managers decision-making by intervening performance management processes.

• 한국도로학회:학술대회논문집
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• 2005.11a
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• pp.369-374
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• 2005

• Asian Journal of Business Environment
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• v.8 no.3
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• pp.23-31
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• 2018

Purpose - The purpose of this study is to analyze the comparative financial performance of outsourcing and vertically integrated corporations from Footwear and Apparel industry. Research design, data, and methodology - Secondary data is collected from the published audited annual reports of the footwear and apparel corporations listed on stock exchanges globally. In the current study, 40 footwear firms have been opted that include 20 vertically integrated and 20 outsourcing firms. The sample is distributed into two groups based on threshold up-to 50 percent respectively outsourcing and vertically integrated companies. Sample independent t-test is applied to compare the financial performance of outsourcing and vertically integrated firms. Results - Based on the investigation of 10 years' data of financial ratio, the results of the study show that there is significant difference between outsourcing and vertical integration strategy on return on assets, return on equity while insignificant difference has found with profit margin. Conclusions - The findings of the current study indicates that there is significant difference between the financial performance of outsourcing and vertically integrated firms in terms of return on asset, return on equity and insignificant difference in terms of profit margin.

• Korea Trade Review
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• v.44 no.3
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• pp.171-189
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• 2019

As many studies have contributed to various aspects of the market by utilizing market orientation, however, this study has tried to overcome limitations of existing studies and suggest more concrete and extended implications. In this study, the relationship between market orientation, responsiveness to market change, and organizational performance of SMEs was examined and compared with characteristics of SMEs (manufacturing and service firms). As a result of the verification, interfunctional coordination has a strong influence on the ability of the organization to respond to market changes as well as customer orientation and competitor orientation. And responsiveness to market change, organizational flexibility has a strong impact on both personal performance and overall team performance. As a result of the comparative study, it can be concluded that manufacturing firms emphasize competitor orientation and organizational agility while service firms emphasize customer orientation and organizational flexibility.

• KEPCO Journal on Electric Power and Energy
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• v.7 no.1
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• pp.115-123
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• 2021

Through machine learning-based load prediction, it is possible to prevent excessive power generation or unnecessary economic investment by estimating the appropriate amount of facility investment in consideration of the load that will increase in the future or providing basic data for policy establishment to distribute the maximum load. However, in order to secure the reliability of the developed load prediction model in the field, the performance comparison verification between the distribution line load prediction models must be preceded, but a comparative performance verification system between the distribution line load prediction models has not yet been established. As a result, it is not possible to accurately determine the performance excellence of the load prediction model because it is not possible to easily determine the likelihood between the load prediction models. In this paper, we developed a reliability verification system for load prediction models including a method of comparing and verifying the performance reliability between machine learning-based load prediction models that were not previously considered, verification process, and verification result visualization methods. Through the developed load prediction model reliability verification system, the objectivity of the load prediction model performance verification can be improved, and the field application utilization of an excellent load prediction model can be increased.