• 디지털융복합연구
• /
• 제14권2호
• /
• pp.235-243
• /
• 2016

모바일 및 사물인터넷 기술의 발전, 대용량 빅데이터 처리, 그리고 클라우드 컴퓨팅 기술의 발전에 힘입어 기존 데이터센터는 클라우드 데이터센터로 변모하고 있다. 클라우드 데이터센터는 ICT 자원들을 가상화하여 운영함으로써 에너지 및 시설 자원을 효율적으로 관리하고 사용자들의 서비스 요구에 빠르게 대응하는 것을 목표로 하고 있다. 이에 따라 클라우드 데이터센터 네트워크는 가상화된 ICT 자원을 효율적으로 제공할 수 있도록 구성되어야 한다. 본 논문은 클라우드 데이터센터에 적합한 네트워크 구조 및 네트워킹 기술을 분석하고 이를 효과적으로 운용하기 위한 방안을 제시한다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2003년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
• /
• pp.335-337
• /
• 2003

원격지에서 임의의 시스템을 제어하는 원격제어(teleoperation)는 자동화산업시스템을 비롯한 많은 분야에서 연구와 활용이 지속적으로 진행되고 있다. 본 논문에서 소개하는 원격 감시제어시스템은 인터넷을 이용 풍력발전기에 적용시킴으로써 카메라를 동해 현장상태를 상시 감시하고, 필요시 원격지 제어를 통해 시스템을 안정적으로 운용하는 데 목적이 있다. 대부분의 풍력발전시스템은 사람이 쉽게 접근하거나 거주하기 용이하지 않는 지역에 설치되고 있으며, 특히 수기 또는 그 이상의 풍력발전기를 운용하는 대규모 풍력발전단지(Wind Farm)에서는 풍력발전기에 따라 자체 현장관리사무소를 설치하고, 헌장관리사무소를 원격지의 중앙통제실에서 종합적으로 관리하는 상황을 고려하면 원격 감시제어시스템은 풍력발전시스템을 구성하는 데 있어 매우 필요한 시스템이라 할 수 있다.

• The Journal of Asian Finance, Economics and Business
• /
• 제7권11호
• /
• pp.927-937
• /
• 2020

Global warming awareness through energy conservation is growing due to the regulatory policies issued by governments and voluntary organization that established carbon emission limits. Transportation is one of the major contributors to carbon emissions. Bike will be simultaneously saving money, getting fit and helping to reduce global warming. Web design has been identified as a key factor for the acceptance and success of the websites and electronic commerce. The purpose of this research is to investigate the effective implementation of the proposed Analytic Hierarchy Process (AHP) technique on a bike case study whose company (Bike Company) is involved in web design for a critical component in the demonstration. Survey research used a variety of data collection methods, with the most common being questionnaires and interviews of some exporters. The research results reveal that the top five key success factors are Good reputation, Transaction security, Ease of use, Promotion, and Diversified choices, which provide the guidelines and directions for decision-makers to design effective websites in the current competitive business scenario. The major findings of this study are suggesting that Internet marketing channels are securing the company's relevance, together with paving the way for methods to increase web traffic.

• 정보보호학회논문지
• /
• 제26권3호
• /
• pp.809-820
• /
• 2016

스마트그리드는 사물인터넷의 핵심 응용서비스이고, 그 중 가장 핵심적인 구성요소인 AMI((Advanced Metering Infrastructure)는 전기사업자와 소비자의 접점에 위치하고 있으며, 스마트 미터는 소비자의 전기사용을 기록하고 사업자에게 전달하는 역할을 한다. 본 논문에서는 스마트그리드에서 소비자와 직접 맞닿아 있는 스마트 미터를 중심으로 AMI에 대한 NESCOR에서 제시하고 있는 사이버공격 및 피해 시나리오를 기반으로 피해비용을 산정한다. 본 연구의 결과는 정책입안자나 전기사업자가 스마트그리드 관련 투자의사결정을 하는데 참고가 될 수 있을 것이다.

• ETRI Journal
• /
• 제33권4호
• /
• pp.528-536
• /
• 2011

In this paper, we analyze the location accuracy of real-time locating systems (RTLSs) in multipath environments in which the RTLSs comply with the ISO/IEC 24730-2 international standard. To analyze the location error of RTLS in multipath environments, we consider a direct path and indirect path, in which time and phase are delayed, and also white Gaussian noise is added. The location error depends strongly on both the noise level and phase difference under a low signal-to-noise ratio (SNR) regime, but only on the noise level under a high SNR regime. The phase difference effect can be minimized by matching it to the time delay difference at a ratio of 180 degrees per 1 chip time delay (Tc). At a relatively high SNR of 10 dB, a location error of less than 3 m is expected at any phase and time delay value of an indirect signal. At a low SNR regime, the location error range increases to 8.1 m at a 0.5 Tc, and to 7.3 m at a 1.5 Tc. However, if the correlation energy is accumulated for an 8-bit period, the location error can be reduced to 3.9 m and 2.5 m, respectively.

• 대한임베디드공학회논문지
• /
• 제10권5호
• /
• pp.281-296
• /
• 2015

This paper describes a novel disaster evacuation system using embedded systems such as smart devices for crisis and emergency management. In indoor environments deployed with the Bluetooth Low Energy(BLE) beacons, smart devices detect their indoor positions from beacon messages and interact with Map Server(MS) and Route Server(RS) in the Internet over the LTE and/or Wi-Fi functions. The MS and RS generate an optimal path to the nearest emergency exit based on a novel graph generation method for less route computation, called the Disaster Evacuation Graph(DEG), for each smart device. The DEG also enables efficient processing of some constraints in the computation of route, such as load balancing in situation of different capacities of paths or exits. All data interfaces among three system components, the MS, RS, smart devices, have been defined for modular implementation of our disaster evacuation system. Our experimental system has been deployed and tested in our building thoroughly and gives a good evidence that the modular design of the system and a novel approach to compute emergency route based on the DEG is competitive and viable.

• 통합자연과학논문집
• /
• 제11권1호
• /
• pp.44-50
• /
• 2018

In this paper, we propose a context-aware power management (CPM) scheme using beacons to reduce the power consumption of personal computers (PCs). In the proposed CPM scheme, the PC, smartphone, control server, and Internet of Things (IoT) device are necessary. PC users first log in the control server using their smartphones and select PCs to turn on. Then, the selected PCs automatically go into three different modes, i.e., sleep, shutdown, and standby power off modes, in order when the PC users leave the PCs without turning off them. Further, we develop a testbed with the proposed CPM scheme using the Arduino with Bluetooth low energy (BLE) and relay modules. Finally, it is shown that the proposed CPM scheme outperforms the conventional scheme in terms of the power consumption.

• 대한가정학회지
• /
• 제39권6호
• /
• pp.109-122
• /
• 2001

This study was performed to identify the roles of residents for the environmentally sound and sustainable development, taco-polis(kologisches Bauen), eco-village and Symbiotic Housing. These buildings will achieve energy efficiency through design strategies such as passive solar heating system, natural cooling and day lighting. Their infrastructure will feature parking on the periphery, extensive pedestrian paths, outdoor ground lights that preserve stellar visibility, and environmentally sensitive technologies such as low writer use fixtures. And they will restore biodiversity while protecting the wildlife, wetlands, forests, soil, air and water. Their houses wile be designed to support home-based occupations, offering high-speed Internet access and other options to promote a localized, sustainable economy. To support and encourage the evolution of sustainable settlements, it is necessary to prepare constructing the physical facilities and the social functions relating with residents. The roles of residents are important to provide a high Quality lifestyle and to integrate a supportive social environment with a low-impact way of life. This study concluded the four main roles of residents for the sustainable of Eco-polis and Ecovillage. 1. Residents assist transition towards a sustainable society as eco-conscious consumers in the planning stage. 2. Residents live in a ecological way for the sustainable ecovillage. 3. Residents exchange information and education for increasing the community glue as a communication network. 4. Residents support and transmit their cultural vitality and tradition for the next generation. So, users are expected to encourage resident's participation in the planning, design, ongoing management and maintenance of the sustainable ecovillage.

• 전기학회논문지
• /
• 제58권5호
• /
• pp.898-904
• /
• 2009

The objective of the present study lies in constructing web-based GIS system providing broad range of information applicable for power/telecommunications distribution facilities through cable. Nowadays, Korea is renowned forits faste sttele communications network across the nation enjoyable for being a test-runbed by worldwide contents providers. It is not too much to say that the trend is caused by the fact that Korea utilizes the cobweb-like power transmission cables applicable for the nationwide telecommunications networking. In particular, the trend has been all the more encouraged by the governmental drive to expedite the telecommunication network by way of the established power transmission facilities deemed as publicutility. Nevertheless, few can deny that the overexcessive competition among telecommunication service providers increasingly gives rise to unauthorized, arbitrary facilitation of distribution devices, which becomes much burden in operating the normal power/telecommunications distribution facilities by a power-generating company. In this regard, the study, to cope with such problems, attempts to develop a web GIS-based information management system compatible with NDIS(New Distribution Information System), a distribution facility management system now under operation by KEPCO, making advantage of GE Energy's SIAS(Smallworld Internet Application) technology. The model provided by this study is expected to get closer into effective operation of distribution facilities along with better sharing of information among conventional telecommunications operators, while getting rid of infringed facilitation cases

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2005년도 춘계학술대회 논문집 디스플레이 광소자 분야
• /
• pp.96-99
• /
• 2005

As the demand of internet networks using backbone communication systems recently increased, the researches on the high-speed wideband optical communication systems are required. For high-speed optical communication systems, asymmetric sampled grating distributed feedback laser diodes (DFB-LDs) are developed and the reliability of DFB-LDs is examined. The reliability of DFB-LDs is performed by monitoring I-V and L-I characteristics and two degradation phenomena related to the electrical characteristics of LDs are observed during the life tests. The first degradation phenomenon by increasing the reverse current is considered as a formation of leakage current path enough to prevent lasing operation in lateral blocking layer near active region of lasers. The second degradation phenomenon by decreasing the forward current is considered as activation of non-radiative Auger recombination process by thermal energy and the second degradation phenomenon is recovered after the off-test period at room temperature Eventually, evaluating the reliability of DFB LDs can allow us to improved the manufacturability in high-volume manufacturing.