• Korean System Dynamics Review
• /
• v.7 no.2
• /
• pp.5-20
• /
• 2006

In the advent of ubiquitous information technology (u-IT) as a new emerging horizon of information society, inflated expectations regarding u-IT are growing very fast and higher than those made in the past, which would perhaps result in serious bust after boom and incur tremendous amount of social costs. This paper thus investigates a dynamic mechanism underlying the coevolution between information technology and society by applying systems thinking, particularly, with a focus on the typical phenomenon, 'hype curve' which shows how new technologies initially grow too fast for their own good, crashing from a peak of inflated expectations into a trough of disillusionment before stabilizing on a plateau of productivity. Three basic questions are explored to answer by investigating the mechanisms underlying the 'boom-bust' phenomenon: First, why hype curve appears in the process of technology and society coevolution. Second, how to enhance the stabilization level. Third, when is the right time for the policy intervention.

• Journal of The Korean Association of Information Education
• /
• v.3 no.1
• /
• pp.1-12
• /
• 1999

By recent advances in the information management tools, Education Softwares and Study Wares.are rapidly developed and distributed over the Internet very fast. As Education Administrative Information systems are developed, information generated from the education field is growing large and fast. In this paper, we suggest a method of efficiently storing and retrieving such information in the large data basis, in real time. We also demonstrate an information system by the proposed method.

• 한국연소학회:학술대회논문집
• /
• 2012.04a
• /
• pp.231-233
• /
• 2012

Circulating Fluidized Bed (CFB) is a technically and economically proven technology for boiler systems and large CFB coal boilers are making inroads into the domestic power boiler market. For biomass gasification, it is also considered as a very promising technology for commercial. Due to the lack of experiences of a large scale CFB gasifier, however, any large scale CFB gasifiers are hard to in Korea in spite of fast-growing demand of domestic market. In this study, a 3 $MW_{th}$ CFB gasifier was developed for biomass gasification. The CFB gasifier consists of interconnected fast and bubbling fluidized bed reactors including unique features for in-situ tar removal. Various numerical and experimental approaches will be presented such as basic modeling works, investigation of hydrodynamics with a cold model, computational particle fluid dynamics and experiments in the 3 MWth gasifier.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.8 no.4
• /
• pp.1178-1191
• /
• 2014

The fault-tolerance routing problem is one of the most important issues in the application of the Internet of Things, and has been attracting growing research interests. In order to maintain the communication paths from source sensors to the macronodes, we present a hybrid routing scheme and model, in which alternate paths are created once the previous routing is broken. Then, we propose an improved efficient and intelligent fault-tolerance algorithm (IEIFTA) to provide the fast routing recovery and reconstruct the network topology for path failure in the Internet of Things. In the IEIFTA, mutation direction of the particle is determined by multi-swarm evolution equation, and its diversity is improved by the immune mechanism, which can improve the ability of global search and improve the converging rate of the algorithm. The simulation results indicate that the IEIFTA-based fault-tolerance algorithm outperforms the EARQ algorithm and the SPSOA algorithm due to its ability of fast routing recovery mechanism and prolonging the lifetime of the Internet of Things.

• Journal of the Society of Naval Architects of Korea
• /
• v.52 no.3
• /
• pp.171-179
• /
• 2015

Usually, in case of wind turbines on land, there are a lot of constraints for installation such as the insufficient installation space and noise pollution. On March 11, 2011, a nuclear leakage accident occurred due to the tsunami caused by the earthquake in Japan and then there have been a rapidly growing interest in floating offshore wind turbines. In this study, an optimization of the substructure of a semi-submersible type floating offshore wind turbine was made. Design variables were set and design alternatives were fixed. UOU-FAST was used for motion analysis in combined environmental conditions of waves and wind. Response Amplitude Operators(RAOs) were compared between the design alternatives.

• Proceedings of the KIPE Conference
• /
• 2017.07a
• /
• pp.188-189
• /
• 2017

There has been a growing demand for power semiconductor switches equipped with high-voltage blocking capability of kV range and fast-switching characteristics of ns range in various plasma application. This paper investigates the application of SiC MOSFETs in the particular plasma application which requires the blocking voltage of 4.5kV and the switching transient time of less than 100ns. In order to meet the required blocking voltage, the series connection of multiple SiC MOSFETs is adopted in this paper. Also, snubber capacitors are employed to equalize the voltage sharing among the series connected SiC MOSFETs. The simulation and experimental result successfully verifies the application of SiC MOSFETs and snubber capacitors in the plasma application requiring high-voltage and fast-switching load dynamics.

• The KIPS Transactions:PartA
• /
• v.11A no.7 s.91
• /
• pp.511-520
• /
• 2004

A peer-to-peer model is very useful in solving the server link bottleneck problem of a client-server model. In this work, we discuss the problems of distributing multimedia content over peer-to-peer network. We focus on two problems in peer-to-peer media content distribution systems. The first is the transmission scheduling of the media data for a multi-source streaming session. We present a sophisticated scheduling scheme called fixed-length slotted scheduling, which results in minimum buffering delay. The second problem is on the fast distribution of media content in the peer-to-peer system that is self-growing. We propose a mechanism accelerating the speed at which the system's streaming ca-pacity increases, called FAST.

• Proceedings of the Korea Forestry Energy Research Society Conference
• /
• 2011.02a
• /
• pp.68-68
• /
• 2011

• Proceedings of the Korea Concrete Institute Conference
• /
• 2001.11a
• /
• pp.135-140
• /
• 2001

This study was developed high-quality a large size precast channel structure using polymer concrete to improve quality of the product as well as to enhance construction quality. Precast PC represent the fastest growing segment of the polymer concrete industry. The fast curing, high strength, and low impermeability permit thin section and rapid reuse of moulds. Developed precast channel structure will be structural experiment and analysis. Also, through an example to construct will be develop the most suitable section survey and make practicable.

• Proceedings of the Korea Contents Association Conference
• /
• 2017.05a
• /
• pp.401-402
• /
• 2017

Advances in the Internet and network technology and the rapidly growing number of personal devices result in the fast growth of E-Commerce, M-Commerce. Nowadays, location-based services are widely used in E-commerce. A location-based service (LBS) is a service based on the geographical positions of mobile handheld devices such as smart phones or tablet computers. In this paper I will view the combination of the E-commerce and LBS.