• 전자통신동향분석
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• 제35권5호
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• pp.30-42
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• 2020

Unlike in previous generations of mobile technology, machine learning (ML)-based self-healing research trend are currently attracting attention to provide high-quality, effective, and low-cost 5G services that need to operate in the HetNets scenario where various wireless transmission technologies are added. Self-healing plays a vital role in detecting and mitigating the faults, and confirming that there is still room for improvement. We analyzed the research trend in self-healing framework and ML-based fault detection, fault diagnosis, and fault compensation. We propose that to ensure that self-healing is a proactive instead of being reactive, we have to design an ML-based self-healing framework and select a suitable ML algorithm for fault detection, diagnosis, and outage compensation.

• International Journal of Control, Automation, and Systems
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• 제3권spc2호
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• pp.355-362
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• 2005

Deregulations and market practices in power industry have brought great challenges to the system planning area. In particular, they introduce a variety of uncertainties to system planning. New techniques are required to cope with such uncertainties. As a promising approach, probabilistic methods are attracting more and more attentions by system planners. In small signal stability analysis, generation control parameters play an important role in determining the stability margin. The objective of this paper is to investigate power system state matrix sensitivity characteristics with respect to system parameter uncertainties with analytical and numerical approaches and to identify those parameters have great impact on system eigenvalues, therefore, the system stability properties. Those identified parameter variations need to be investigated with priority. The results can be used to help Regional Transmission Organizations (RTOs) and Independent System Operators (ISOs) perform planning studies under the open access environment.

• 대한화학회지
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• 제31권3호
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• pp.280-286
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• 1987

페나실 치환 벤젠술포네이트류와 피리딘의 반응속도를 아세토니트릴과 메탄올 용매속에서 각각 35, 45, 그리고 $55^{\circ}C$에서 전기전도도법으로 측정하였다. 이탈기 내의 치환기 효과는 치환기의 전자끌기 능력이 클수록 반응이 빨라지므로써 이탈기의 이탈 능력이 반응속도에 직접 영향을 미쳤다. 또한 양성자성 용매인 메탄올과 비양성자성 용매인 아세토니트릴에서의 반응을 비교한 결과 수소결합을 통한 특성 용매화가 작용되고 있음을 알수 있었다. 그러므로 이 반응에서 피리딘이 기질의 카르보닐기에 속도 결정 단계로 첨가되는 메카니즘을 배제시킬수 있었다

• International journal of advanced smart convergence
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• 제9권3호
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• pp.253-259
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• 2020

Most of today's large-scale cloud systems and enterprise data centers are distributing resources to improve scalability and resource utilization. NVMe-over-Fabric protocol allows submitting NVMe commands to a remote NVMe SSD through RDMA (Remote Direct Memory Access) network. It is attracting attention recently because it is possible to construct a disaggregation storage system with low latency through the protocol. However, the current I/O stack of NVMe-over-Fabric has an inefficient structure for maintaining compatibility with the traditional I/O stack. Therefore, in this paper, we propose a new mechanism to reduce I/O latency and CPU overhead by modifying I/O path of NVMe-over-Fabric to pass through legacy block layer. According to the performance evaluation results, the proposed mechanism is able to reduce the I/O latency and CPU overhead by up to 22% and 24% compared to the existing NVMe-over-Fabrics protocol, respectively.

• 산업기술연구
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• 제24권A호
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• pp.75-81
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• 2004

The metal halide lamps are now widely used in the application and commercial lighting due to their attracting properties such as good color rendering and high efficiency. But, they have the serious problem of acoustic resonance for high frequency operation and they need the high voltage to ignite. So, they have not been applied to indoors. Over the past few years, a considerable number of studies have been conducted on the electronic ballast together with hot restarting and resonance phenomenon. But, very few attempts have been made with the adaptive ignition method according to the lamp state. In this paper, electronic ballast is proposed for metal halide lamps with an igniter for adaptive ignition. The proposed electronic ballast can generate different ignition voltages according to the arc tube state.

• 한국병원경영학회지
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• 제17권4호
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• pp.58-70
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• 2012

The purpose of this study is to examine the preparation of medical institutions for medical tourism and its effects. The sample of this study were 99 case which were selected from Korea Health Industry Development Institute list. Data were collected through the mail questionnaire survey from Sept. 15 to Oct. 30 in 2010. The collected data were analyzed using Chisquare test, t-test. The main findings of study are as follows: Using Chisquare test, we found statistically significant differences in resources prepared for medical tourism between hospitals and clinics. In general, hospitals were well prepared in human resources(e.g., proportion of employees with foreign language capability) and physical resources(e.g., helpdesk, brochures) compared to clinics.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.249-252
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• 2006

Recently, as it has greatly increased the demand on the serviceability of subway, cable tunnel and underground storage, the stability of tunnel structures has been attracting the concern of engineers and researchers. Thus the aim of the present study is to evaluate acid attack resistance of shotcrete using in tunnel structures. And, in order to understand the deterioration mechanism, test using scanning electron microscopy(SEM) analysis and X-ray diffraction showed that the deterioration mechanism due to acid attack in shotcrete.

• Journal of Information Technology Applications and Management
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• 제22권2호
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• pp.95-112
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• 2015

Spread of internet service had a huge effect on usage and spread of SNS world widely. Variety of the service has increased from human network managing to commerce, education, payment method and so on. Also, it is expanding its service territory to not only PC area but also that of mobile equipment with development of information technology. Spread of use on SNS provides existing corporations the expansion of service area. Late SNS starter companies are advancing in diverse way for attracting users by serving shopping, games and other services with association with SNS. Therefore, analysis on consumers' thought and pattern which analyze users' demand, service's function and contents and other factors in order to reflect on plans and operations of SNS is needed. On this perspective, this research is suggesting properties that are crucially related to sustained usage of SNS and study factors of SNS's characteristics that influence trust and satisfaction on SNS and continuous usage intent of SNS.

• 한국공간구조학회논문집
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• 제1권2호
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• pp.101-110
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• 2001

A large floating structure is attracting great attention in recent years from the view of ocean space utilization. Its huge scale in the horizontal directions compared with the wavelength and relatively shallow depth make this type of floating structure flexible and its wave-induced motion be characterized by the elastic deformation. In this paper, a boundary integral equation method is proposed to predict the wave-induced dynamic response mat-like floating offshore structure. The structure is modeled as an elastic plate and its elastic deformation is expressed as a superposition of free-vibration modes in air. This makes it straightforward to expand the well-established boundary integral technique for rigid floating bodies to include the hydroelastic effects. In order to validate the theoretical analysis, we compare with the experimental result of reduced model test. Satisfactory agreement is found between theory and experiment.

• 통상정보연구
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• 제11권2호
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• pp.83-110
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• 2009

China's logistics industry is an growing one at a very higher rate, owing to the rapid expansion of the country's industrial base and the rise of domestic consumer markets. Essential to the development of china's economy, policy makers have paid constant attention to the logistics sector which is attracting growing volumes of both foreign and domestic investment. The inefficiencies are exacerbated by a number of factors such as transportation bottlenecks, regulatory constraints and local barriers to entry. Foreign and foreign-invested logistics companies have typically cornered the express delivery (for example DHL, FedEX), sea freight forwarding and specialized logistics services (for example Hanjin Shipping). The purpose of this paper is to contribute to the activation of Korean companies' entry into China's logistics market by studying the strategies and types for Korean companies enter into China's logistics Market.