• Journal of Communications and Networks
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• v.8 no.4
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• pp.432-441
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• 2006

As the community antenna television (CATV) networks becomes ubiquitous, instead of constructing an entirely new broadband network infrastructure, it has emerged as one of the rapid and economic technologies to interconnecting heterogeneous network to provide broadband access to subscribers. How to support ubiquitous real-time multimedia applications, especially in a heavy traffic environment, becomes a critical issue in modern CATV networks. In this paper, we propose a time guaranteed and efficient upstream minislots allocation algorithm for supporting quality-of-service (QoS) traffic over data over cable service interface specification (DOCSIS) CATV networks to fulfill the needs of realtime interactive services, such as video telephony, video on demand (VOD), distance learning, and so on. The proposed adaptive fast expansion algorithm and the loading statistics with dynamic swapping algorithm have been shown to perform better than that of the multimedia cable network system (MCNS) DOCSIS.

• Journal of the Korea Society for Simulation
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• v.12 no.3
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• pp.83-94
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• 2003

For 24 hours-7 days service on distributed systems, a great deal of efforts are investigated on high availability for seamless operation. In this paper, we propose a dynamic reconfiguration framework of distributed systems, called "hot-swapping" framework. This framework allows us to upgrade and exchange a number of modules of a distributed system without stopping running service as well as the system itself. In order to hide the state of service operation, the framework employes the "proxy" design pattern. Our framework provides two types of proxies: a static proxy and a dynamic proxy, Static proxies can achieve fast execution time, but they need to be changed whenever any minor change exists in the related swappable module. Meanwhile, dynamic proxies takes longer execution time, but do not need to be changed under minor changes of swappable modules. We compare performances of static and dynamic proxies and also apply the framework to a real situation with security management modules. management modules.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.10
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• pp.60-64
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• 2015

Many people think that Electric Vehicles(EVs) is the best method to resolve the problems of running out of fossil fuels. But EVs take long time for charging. So, EVs with battery swapping systems(EVBS) are developed to resolve this problem. Nonetheless, EVBS is not spreaded widely because the method of durability test in couplers is not defined. In this study, the evaluation method of durability test in couplers is defined by some standards and the measurement uncertainty is used to increase the reliability of EV couplers.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1998.05a
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• pp.327-332
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• 1998

최근 들어 수요와 공급이 급격히 증가하고 있는 PDA(Personal Digital Assistants)의 운영체제는 기존에 많이 연구되어 왔던 운영체제 환경과는 하드웨어의 특성상 메모리 관리나 파일 시스템 등에서 많은 차이점을 보인다. 예를 들어 작은 메모리 용량과 하드디스크 없이 메인 메모리만을 사용해서 모든 데이터를 저장해야 하므로 이를 얼마나 효율적으로 관리해야 하는지가 문제점이 된다. 여기서 우리는 PDA 중에서 비교적 많은 사용자 중을 갖고 있는 USRobotics 사의 PalmPilot [1]을 대상으로 도킹 데스크탑을 이용한 swapping 방법을 모색해 보았다. 기존의 PalmPilot은 그림 1과 같이 데스크탑과 연결하여 자료의 백업과 동기화 작업만을 수행하였다. 하지만 이 순간만큼은 Palmpilot도 일반 데스크탑과 같이 대용량의 하드디스크를 사용할 수 있는 기회가 생기므로 이 때를 잘 이용한다면 사용자는 좀 더 커다란 데이터를 사용할 수 있게 될 것이다.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.559-559
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• 2005

• BMB Reports
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• v.40 no.4
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• pp.539-546
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• 2007

The lysozymes encoded by bacteriophage T7 and K11 are both bifunctional enzymes sharing an extensive sequence homology (75%). The constructions of chimeric lysozymes were carried out by swapping the N-terminal and C-terminal domains between phage T7 and K11 lysozymes. This technique generated two chimeras, T7K11-lysozyme (N-terminal T7 domain and C-terminal K11 domain) and K11T7-lysozyme (N-terminal K11 domain and C-terminal T7 domain), which are both enzymatically active. The amidase activity of T7K11-lysozyme is comparable with the parental enzymes while K11T7-lysozyme exhibits an activity that is approximately 45% greater than the wild-type lysozymes. Moreover, these chimeric constructs have optimum pH of 7.2-7.4 similar to the parental lysozymes but exhibit greater thermal stabilities. On the other hand, the chimeras inhibit transcription comparable with the parental lysozymes depending on the source of their N-terminals. Taken together, our results indicated that domain swapping technique localizes the N-terminal region as the domain responsible for the transcription inhibition specificity of the wild type T7 and K11 lysozymes. Furthermore, we were able to develop a simple and rapid purification scheme in purifying both the wild-type and chimeric lysozymes.

• ETRI Journal
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• v.23 no.3
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• pp.106-110
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• 2001

Subpicosecond all-optical switching method based on the simultaneous two-photon coherence exchange is proposed and numerically demonstrated. The optical switching mechanism is based on the optical field induced dark resonance swapping via nondegenerate four-wave mixing processes. For potential applications of ultrafast all-optical switching in fiber-optic communications, 10-THz channel number independent quantum router is discussed.

• ETRI Journal
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• v.36 no.5
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• pp.741-751
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• 2014

Smart TV is expected to bring cloud services based on virtualization technologies to the home environment with hardware and software support. Although most physical resources can be shared among virtual machines (VMs) using a time sharing approach, allocating the proper amount of memory to VMs is still challenging. In this paper, we propose a novel mechanism to dynamically balance the memory allocation among VMs in virtualized Smart TV systems. In contrast to previous studies, where a virtual machine monitor (VMM) is solely responsible for estimating the working set size, our mechanism is symbiotic. Each VM periodically reports its memory usage pattern to the VMM. The VMM then predicts the future memory demand of each VM and rebalances the memory allocation among the VMs when necessary. Experimental results show that our mechanism improves performance by up to 18.28 times and reduces expensive memory swapping by up to 99.73% with negligible overheads (0.05% on average).

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.3
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• pp.343-351
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• 2018

Renewable energy sources has drawn considerable attention as clean energy sources because of changing public attitudes regarding greenhouse gas and fine dust. Recently, in this respect, the government provides the drivers of electric vehicles with various benefits such as tax reduction, financial incentives and free parking from the public to the private sector. Plug-in electric vehicles are the most common in the private sector. Otherwise, different types of battery-based buses in the public sector are being developed, and there are three main types of charging: plug-in, battery swapping and wireless. Therefore, economic assessment of charging types in each bus route is required in order to facilitate the use of battery-based buses instead of the existing CNG buses. In this paper, net present value(NPV) and B/C ratio of charging types are evaluated in consideration of the bus schedule, the cost of charging station, and the life cycle of battery, etc. per each bus route. In case study, main bus routes in Daegu City are simulated with the proposed evaluation method to validate the eco-bus project.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2008.10a
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• pp.90-93
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• 2008

In natural language, it is common that repetitive constituents in an expression are to be left out and it is necessary to figure out the constituents omitted at analyzing the meaning of the sentence. This paper is on recognition of boundaries of parallel noun phrases by figuring out constituents omitted. Recognition of parallel noun phrases can greatly reduce complexity at the phase of sentence parsing. Moreover, in natural language information retrieval, recognition of noun with modifiers can play an important role in making indexes. We propose an unsupervised probabilistic model that identifies parallel cores as well as boundaries of parallel noun phrases conjoined by a conjunctive particle. It is based on the idea of swapping constituents, utilizing symmetry (two or more identical constituents are repeated) and reversibility (the order of constituents is changeable) in parallel structure. Semantic features of the modifiers around parallel noun phrase, are also used the probabilistic swapping model. The model is language-independent and in this paper presented on parallel noun phrases in Korean language. Experiment shows that our probabilistic model outperforms symmetry-based model and supervised machine learning based approaches.