• Advances in nano research
• /
• v.5 no.1
• /
• pp.61-67
• /
• 2017

A semi-empirical approach to model the temperature effects on I-V characteristics of Carbon Nanotube Field Effect Transistors (CNTFETs) is proposed. The model includes two thermal parameters describing CNTFET behaviour in terms of saturation drain current and threshold voltage, whose values are extracted from the simulated and trans-characteristics of the device in different temperature conditions. Our results are compared with those of a numerical model online available, obtaining I-V characteristics comparable but with a lower CPU calculation time.

• Korean Journal of Microbiology
• /
• v.18 no.2
• /
• pp.59-66
• /
• 1980

Two strains S-P and S-P-2, both Streptomyces sp., have been isolated and were found to have relatively high specific enzyme activity compared to other organisms reported. The specific activity of the enzyme produced from these two strains were 0.25 and 0.2 international units respectively. The productivity of the enzyme achieved was about 50 IU/l/hr. Glucose isomerase form these strains was found to be stable under the temperature of heat treatment (at $65^{\circ}C$) for fixation of enzyme inside the dell. This organism has an advantage in that it did not require toxic metalic ion for enzyme activity and could utilize xylan in leu of xylose as an inducer. The optimal temperature and pH of enzymatic reaction purpose of using these data for the optimal operation and designing of enzyme reactor system. The reaction mechanism was found to follow the single substrate reversible reaction kinetics. The kinetic constants determined experimentally are : $K_{mf}=0.33M,\;K_{mb}=1.0M,\;V_{mf}=0.88{\mu}mole\;per\;min.,\;V_{mb}= 2.96{\mu}mole\;per\;min.\;and\;K_{eq}=0.74.

• Structural Monitoring and Maintenance
• /
• v.1 no.2
• /
• pp.173-182
• /
• 2014

We describe the application of a distributed optical fiber sensor based on stimulated Brillouin scattering, as an integrated system for safety monitoring of railway infrastructures. The strain distribution was measured statically and dynamically along 60 meters of rail track, as well as along a 3-m stone arch bridge. We show that, gluing an optical fiber along the rail track, traffic monitoring can be performed in order to identify the train passage over the instrumented sector and determine its running conditions. Furthermore, dynamic and static strain measurements on a rail bridge are reported, aimed to detect potential structural defects. The results indicate that distributed sensing technology represents a valuable tool in railway traffic and safety monitoring.

• Animal Systematics, Evolution and Diversity
• /
• v.6 no.1
• /
• pp.29-56
• /
• 1990

In the course of the study program of benthic invertebrates of the coastal shelves of Korean Peninsula, the shallow -water chitons (Mollusca : Polyplacophora) are studied based on the collections of the Korea Ocean Research and Development Insitute made between 1980 and 1983. A total of sixteen species belonging to the Orders Lepidopleurina and Ischnochitonina , are now recognized from Korean waters,of which the following two species are newly recorded ; Leptochiton (Leptochiton ) rugatus (Carpenter in Pilsbry), and Mopalia schrencki Thiele. Illustrations, description and complte synonymies are provided for each of them.

• Management & Information Systems Review
• /
• v.26
• /
• pp.133-152
• /
• 2008

In the knowledge and network economy, standards and standardization become an important factor in determining the competitiveness of nations and firms. This paper analyses some cases of firms' strategic standardization. We defined the concept of standards, standardization, strategic standardization, and standardization management, which have been unfamiliar in the academic society. The standardization strategy can be categorized into four types according to firm's management objectives or benefits, including technological innovation, market creation/extension. cost-down, and accreditation. This classification of standardization strategy is very useful in analysing the various kinds of the cases of strategic standardization implementation. We found that standards and standardization have a positive influence on firm's overall performance. In some cases, for example, Dell Computer, Sun Microsystems, Deere & Company, etc., strategic standardization plays a role as a key success factor(KSF).

• Wind and Structures
• /
• v.3 no.1
• /
• pp.41-58
• /
• 2000

According to research currently developed by several authors (including the present ones) a multimode approach to the aeroelastic instability can be appropriate for suspension bridges with very long span and so with close natural frequencies. Extending that research, this paper deals in particular with: i) the role of along-wind modes, underlined also by means of the flutter mode representation; ii) the effects of a variation of the mean wind speed along the span. A characterisation of the response in the time domain by means of an energetic approach is also discussed.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 1993.06a
• /
• pp.1033-1036
• /
• 1993

Most of the today realized fuzzy logic control applications has been designed using different heuristic approaches for synthesis and implemented with conventional programming languages on general purpose microcontrollers. This paper aims to present a new methodology to design a fuzzy controller. The methodology is based on the Cell-to-Cell approach to extract the control law. A set of fuzzy rules is then found by using a FAM (Fuzzy associative memories) approach. The proposed procedure was implemented to control the rotor position of a DC motor.

• Journal of Communications and Networks
• /
• v.6 no.2
• /
• pp.173-181
• /
• 2004

This paper shows a technique for regulating the rate emitted by UWB mobile terminals. This technique is designed to adapt the emission rate to the effects of channel capacity variations. We assume that individual flows are shaped at edge routers by means of dual leaky buckets. The proposal is based on the evaluation of certain parameters, which reflect the channel status, sent to the application layer. This information is generated by the scheduler designed to guarantee appropriate channel sharing for the various traffic components. We describe some results which highlight how performance depends on the specific operating conditions, as well as on the traffic descriptors of the flows, their reciprocal difference, and performance requirements.

• Structural Engineering and Mechanics
• /
• v.10 no.2
• /
• pp.181-195
• /
• 2000

A two-step procedure for the application of non linear constrained programming to the limit analysis of rigid brick-block systems with no-tension and frictional interface is implemented and applied to various masonry structures. In the first step, a linear problem of programming, obtained by applying the upper bound theorem of limit analysis to systems of blocks interacting through no-tension and dilatant interfaces, is solved. The solution of this linear program is then employed as initial guess for a non linear and non convex problem of programming, obtained applying both the 'mechanism' and the 'equilibrium' approaches to the same block system with no-tension and frictional interfaces. The optimiser used is based on the sequential quadratic programming. The gradients of the constraints required are provided directly in symbolic form. In this way the program easily converges to the optimal solution even for systems with many degrees of freedom. Various numerical analyses showed that the procedure allows a reliable investigation of the ultimate behaviour of jointed structures, such as stone masonry structures, under statical load conditions.

• Electronics and Telecommunications Trends
• /
• v.34 no.2
• /
• pp.51-59
• /
• 2019

Edge computing, which is computing on the edge of the network, is becoming a market value as a means of overcoming the fear of communication disconnection and delay reduction, which are the technical weaknesses of cloud computing. Edge computing is continuously expanding applications in various applications such as safety industry, smart factories, autonomous vehicles, mobile communications, and AR/VR. Looking at edge computing trends from Microsoft, IBM, HPE, and Dell EMC, current edge computing must be understood as an integral binding technology and not as a simple complement to the cloud. This paper examines market trends in edge computing and analyzes the impact of edge computing on major related industries.