• Progress in Superconductivity and Cryogenics
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• v.7 no.2
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• pp.47-51
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• 2005

This paper is for studying the feasibility of SFCL application for the interconnection operation of 154kV power systems under 345kV S/S in Korean power system. All Korean 154kV power systems are constructed as loop systems in downtown. However, the present 154kV systems are operated with separated systems around 345kV S/S because of fault current and overload problems. In this study, we investigate the structure and operation of 154kV power system in Seoul and study the feasibility of interconnection operation of 154kV systems under 345kV systmes by applying SFCLs to 154kV bus-tie.

• Proceedings of the Korean Biophysical Society Conference
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• 1996.07a
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• pp.4-4
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• 1996

$\alpha$$_1$-arantitrypsin, a member of the serpin (serine protease inhibitor) family, undergoes a large structural rearrangement upon the cleavage and insertion of the reactive site loop. This conformational change is driven by the metastability of the native serpin structures and has an important role in the regulation of the inhibitory-serpin function. (omitted)

• Journal of the Korean housing association
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• v.15 no.1
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• pp.153-161
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• 2004

The purpose of this study is to analysis the environmental characteristics in the small urban village consist of the detached houses. Three detached houses with the different urban structure and physical characteristics are selected, we survey the physical characteristics and investigate the residential satisfaction. As a result of the study, (1) A loop street pattern is more desirable for a community than a grid pattern, (2) The wall of the residential boundary makes residents get the sense of territory and community, and it facilitates no wall or tree fence of the each detached house. (3) The community spaces have an effect up on the sense of community. (4) It is desirable that the residents participate in a management of the detached housing area.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.3
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• pp.407-414
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• 1996

In this paper we consider the variable structure control for a class of discrete-time uncertain multivariable systems where the nominal system is linear. Discrete-time switching dynamics are introduced so that a new type of state trajectories called sliding mode may exist on the sliding surface by state feedback. The quantitative analysis for the matched uncertainties will show that every response of the system with the proposed switching dynamics is bounded within small neighborhoods of the state-space origin. Also, by the similarity transformation it will be shown that the eigenvalues of the closed-loop systems are composed of those of the subsystems which govern the range-space dynamics and null-space dynamics. It will be also shown that ideal sliding mode can be obtained in the absence of uncertainties due to one-step attraction to the sliding surface regardless of initial position of states. (author). 12 refs., 2 figs.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.3
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• pp.50-61
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• 1994

A method for performing dynamic design sensitivity analysis of vehicle suspension systems which have three dimensional closed-loop kinematic structure is presented. A recursive form of equations of motion for a MacPherson suspension system is derived as basis for sensitivity analysis. By directly differentiating the equations of motion with respect to design variables, sensitivity equations are obtained. The direct generalize for the application of multibody dynamic sensitivity analysis. Based on the proposed sensitivity analysis, optimal design of a MacPherson suspension system is carried out taking unsprung mass, spring and damping coefficients as design variables.

• Journal of Electrical Engineering and Technology
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• v.9 no.4
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• pp.1349-1354
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• 2014

This paper presents a compact and portable high-voltage generator based on magnetic-core Tesla transformer for driving an UWB high power electromagnetic source. In order to optimize the performance of the high-voltage generator, a novel open-loop cylindrical magnetic-core adopting the quad-division lamination structure is proposed and manufactured. The designed high-voltage generator using the proposed magnetic core has a battery-powered operation and compact size of $280mm{\times}150mm$ in length and diameter, respectively. The high-voltage generator can produce a voltage pulse waveform with peak amplitude of 450 kV, a rise time of 1.5 ns, and pulse duration of 2.5 ns at the 800 V input voltage.

• Bulletin of the Korean Chemical Society
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• v.21 no.8
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• pp.813-816
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• 2000

The synthesis of bisphenol A-derived calixarenes has been studied by changing the protecting group of the phe-nol moiety and reaction conditions. Depending on the protecting groups,the corresponding calix[6,7,8]arenes are obtained in different rat ios. For example, whcn mono-p-tert-butyldimethylsilyl-protected bisphenol A is treated with paraformaldehyde and a catalytic amount ofaqueous KOH in refluxing p-xylene with a Dean-Stark water collector for 36 h, the corresponding calix[8]arene, calix[7]arene, and calix[6]arene are producedand separated in the ratio of about 3 : 2 : l and with overall 63% yield. The calixarenes are characterized by NMR spectroscopy and mass analysis. The X-raycrystal structure of the calix[8]arene shows a pleated loop confor-mation, stabilized by intramoIecular hydrogen bonding between the inner phenolic hydroxy groups.

• Journal of the Semiconductor & Display Technology
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• v.20 no.2
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• pp.67-72
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• 2021

MANET(Mobile Ad Hoc Network) is the structure in which a source node communicates with a destination node by establishing a route with neighbor nodes without using the existing wired or wireless network. Therefore, the routing protocol for MANET must correspond well to changes in the channel state of moving nodes, and should have simple operation, high reliability, and no routing loop. In this paper, the simulation was perform by using a traffic model with on/off two states provided by the NS-3 network simulator. Also, the duration of the ON state and the duration of the OFF state used the traffic where inter arrival time of data is irregular by generating random values with constant, exponential distribution, and Pareto distribution. The performance of the DSDV, OLSR, and AODV protocols was compare and analyzed using the generated traffic model.

• Textile Coloration and Finishing
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• v.33 no.4
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• pp.182-190
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• 2021

The purpose of this study is to provide the dyeing and physical characteristics of napped knit fabrics composed of latent crimped yarn. The K/S values, dyeing fastness, thickness, bulkiness, and shrinkage characteristics of three knit fabrics were investigated. The original knit fabric (SK) was composed of 1ply latent crimped yarn (75/36) in the ground and PET DTY (70/100) in the pile loop, in order of napped process the napped knit fabric (SN) was napped SK fabric. In order to compare of latent crimped yarn content, the last knit fabric (DN) was napped 2ply latent crimped yarn were included in the same structure of SK. Dyeability of three knit fabrics was similar but the shrinkage properties of DN fabric were significant different. The bulkiness shows a tendency to increase the bulkiness as increasing the dyeing temperature, and the bulkiness of the SN was higher because of the napping process and optimal content of latent crimped yarn.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.1
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• pp.37-47
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• 2005

This Paper proposes a practical design and implementation methodology for a disturbance rejection controller. In a 2 Degree-Of-Freedom (DOF) structure, disturbance rejection performance can be improved without a high gain in forward-loop controller which might cause unwanted side-effects in conventional controller. But, since design methodology of 2 DOF controller is originally derived from the 2 DOF theory, it is not easy to utilize fer various industrial applications. Disturbance observer is a simple, but very effective 2 DOF controller. In this paper, practical issues are discussed from basic idea of DOB to technical procedure for design and implementation. Additionally, a methods and their examples of experimental modeling are explained. The proposed method is demonstrated by two examples of linear-type motor systems.