• Journal of Advanced Navigation Technology
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• v.22 no.4
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• pp.325-335
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• 2018

Limited access to state information in the design of a feedback controller has brought out a significant amount of research on the design of an output feedback controller. Despite its long endeavor to find an optimal one, it is still an open problem. Thus, we focus on the comparison of existing states of arts in the design of a static output feedback controller in terms of stability and complexity so as to find further research direction in this field. To this end, we present eight design methods in a unified presentation. We also provide the complete description of algorithms which can be applicable to any system configuration. Stability performance and complexity in terms of processing time are evaluated through numerical simulations. Simulation results show that the algebraic controller (AC) algorithm [20] has the smallest complexity while the scaling linear matrix inequality (SLMI) algorithm [18] seems to achieve the best stability in most cases with much higher complexity.

• Progress in Superconductivity and Cryogenics
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• v.23 no.3
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• pp.51-54
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• 2021

The DC system has less power loss compared to the AC system because there is no influence of frequency and dielectric loss. However, the zero-crossing point of the current is not detected in the event of a short circuit fault, and it is difficult to interruption due to the large fault current that occurs during the opening, so the reliability of the DC breaker is required. As a solution to this, an LC resonance DC circuit breaker combined a superconducting element has been proposed. This is a method of limiting the fault current, which rises rapidly in case of a short circuit fault, with the quench resistance of the superconducting element, and interruption the fault current passing through the zero-crossing point through LC resonance. The superconducting current limiting element combined to the DC circuit breaker plays an important role in reducing the electrical burden of the circuit breaker. However, at the beginning of a short circuit fault, superconducting devices also have a large electrical burden due to large fault currents, which can destroy the element. In this paper, the reactor is connected to the source side of the circuit using PSCAD/EMTDC. After that, the change of the fault current according to the reactor capacity and the electrical burden of the superconducting element were confirmed through simulation. As a result, it was confirmed that the interruption time was delayed as the capacity of the reactor connected to the source side increased, but peak of the fault current decreased, the zero-crossing point generation time was shortened, and the electrical burden of the superconducting element decreased.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.6
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• pp.2168-2187
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• 2021

The smart grid replaces the traditional power structure with information inventiveness that contributes to a new physical structure. In such a field, malicious information injection can potentially lead to extreme results. Incorrect, FDI attacks will never be identified by typical residual techniques for false data identification. Most of the work on the detection of FDI attacks is based on the linearized power system model DC and does not detect attacks from the AC model. Also, the overwhelming majority of current FDIA recognition approaches focus on FDIA, whilst significant injection location data cannot be achieved. Building on the continuous developments in deep learning, we propose a Deep Learning based Locational Detection technique to continuously recognize the specific areas of FDIA. In the development area solver gap happiness is a False Data Detector (FDD) that incorporates a Convolutional Neural Network (CNN). The FDD is established enough to catch the fake information. As a multi-label classifier, the following CNN is utilized to evaluate the irregularity and cooccurrence dependency of power flow calculations due to the possible attacks. There are no earlier statistical assumptions in the architecture proposed, as they are "model-free." It is also "cost-accommodating" since it does not alter the current FDD framework and it is only several microseconds on a household computer during the identification procedure. We have shown that ANN-MLP, SVM-RBF, and CNN can conduct locational detection under different noise and attack circumstances through broad experience in IEEE 14, 30, 57, and 118 bus systems. Moreover, the multi-name classification method used successfully improves the precision of the present identification.

• Textile Coloration and Finishing
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• v.33 no.4
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• pp.210-219
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• 2021

It was intended to conduct basic research to reduce development lead time and cost consumed in DTP process technology development. For the simulation of HTPE fabric, virtual engineering software was used to generate fiber model, yarn model, fabric model, and finite element model of HTPE fiber. The purpose of this study is to analyze the correlation and error rate between the stiffness numerical analysis results according to the direct DTP process parameters using reactive dyes in the generated finite element model and the stiffness measurements of the actual sample ac- cording to ASTM D1388. And, after dyeing the HTPE plain fabric according to the direct DTP process parameters, we want to analyze the dyeability of the HTPE fabric fabrics according to the direct DTP process parameters through the color fastness analysis. When looking at the results of the analysis of the finite element model, a higher value was shown when the distance between the nozzle and the fabric was 3mm than when the distance was 10mm. When the distance between the nozzle and the fabric was 10mm and 7mm, the reactive dye did not penetrate sufficiently, resulting in poor clarity when viewed with the naked eye.

• Childhood Kidney Diseases
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• v.7 no.1
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• pp.52-59
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• 2003

Purpose : The renin-angiotensin system(RAS) plays an important role in renal growth and development. We have studied the prevalence of renal anomalies and documented the association between karyotype and renal anomalies using IVP and ultrasonography. Furthermore, to investigate the impact of RAS gene polymorphism on renal anomaly in Turner syndrome, we examined the ACE I/D genotype, angiotensinogen(AGT) gene M235T, angiotensin receptor type 1(ATR) gene A1166C. Methods : Cytogenetic analysis was performed in 33 Turner syndrome patients on peripheral blood lymphocytes. Ultrasonography(US) of the kidneys and collecting system and intravenous pyelography(IVP) were perfomed in all patients. Nuclear scintigraphy{Tc 99m dimercaptosuccinic acid(DMSA) scan} was also performed for the definite renal diagnosis if indicated. And, ACE I/D genotype, angiotensinogen(AGT) gene M235T, angiotensin receptor type 1(ATR) gene A1166C were examined by PCR amplification of genomic DNA samples. Results : The prevalence of renal anolmalies in Turner syndrome was 36.4%(12/33). The Karyotype 45, X was observed in 18 of the 33 girls(54.5%), of whom 8(44.4%) had renal anomalies. Mosaic karyotypes were observed in 11(33.3%) and four(12.2%) had a non-mosaic structural aberration of the X chromosome. In this group 4(25.7%) had renal anomalies. More renal anomalies were associated with the 45, X karyotype than those with mosaic/structural abnormalities of X chromosome, but the difference was not statistically significant(P>0.05). And, there was no significant differences in the RAS gene polymorphism and allele frequencies between renal anomaly group and normal group in Turner syndrome. Conclusion : The prevalence of renal anolmalies in Turner syndrome was 36.4%. There is no significant differences in the RAS gene polymorphism and allele frequencies between the renal anomaly group and the normal group in Turner syndrome.

• The korean journal of orthodontics
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• v.30 no.2 s.79
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• pp.245-260
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• 2000

The Objective of this research was to construct the multimedia database system that was necessary for the education of the practitioners and the students. To establish this system, there were technical problems as follows 1) The processing of the images, 2) The rapid processing of the information with the computer network, 3) The development of diagnosis tools, 4) The technique to establish the database system, 5) The link between the database system and the internet, and 6) The method to educate through many cases. The analysis for diagnosis and treatment planning were provided as two parts : model analysis and cephalometric analysis. As a model analysis, arch length discrepancy and Bolton tooth ratio were provided for the part of patient information. Cephalometric analyses were provided in the part of initial diagnosis. The Cephalometric analysis ver 2.0 and the PowerCeph pro 3.3.5 were used to show Tweed, Steiner and Jarabak analysis. In the main part, Kim's analysis and some measurements were added. In the post-treatment or retention part, we show the superimposition of the cephalometrics with which you can find the effectiveness of the various orthodontic treatment The address of this home page is "http://damis.snu.ac.kr/orthodontics"

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.12
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• pp.2641-2646
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• 2009

The more growing on home automation system at automatic control, the more efficiency required for energy consumption and for recycling energy in near future. Heating is essential in general apartment. Heating method is two types in apartment. One uses electricity, and other one uses warm water. If use electricity, is not efficient by rise of electric charges. But, It can reduce much in expense aspect, if use warm water. When use warm water, temperature of warm water is not equal from all pipe parts. Therefore, indoor tempera can be unequal with set point. Solution of these problems is as following. Temperature sensor in warm water attach pipe. The measured temperature transmits by real time. Temperature of warm water controls in receiver side. In this paper, we propose an automatic temperature transmission system for the heating pipe at home, that is a low-power based, and supply the energy source from a small AC motor resided in bottom cement mortal. The proposed system is used in power mechanism from a collision process of water-jet using propeller water-difference and also designed a CPU module by Atmega8 at ATMEL co., Inc. and a communication module by CC1020 at Chipcon co., Inc.

• Applied Chemistry for Engineering
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• v.9 no.6
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• pp.870-877
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• 1998

With impedance spectrum measurements, impedance was studied in the interface between sample solutions for $K^+-ion$ selective PVC membrane electrode containing neutral carriers [dibenzo-18-crown-6 (D18Cr6) and valinomycine (Val)]. Response characteristics of electrode were examined by measuring AC impedance spectra that were resulted from the chemical structure and the content of carrier, variation of plasticizer, membrane thickness, doping of base electrolytes, and concentration variation of sample solution. Transport characteristics of PVC membrane electrode were also studied. It was found that the equivalent circuit for the membrane in $K^+$ solution could be expressed by a series combination of solution resistance and a parallel circuit consisting of the bulk resistance and geometric capacitance of the membrane system. But the charge transfer resistance and Warburg resistance were overlapped a little in the low concentration and low frequency ranges. The carrier, D18Cr6 was best for electrode and impedance characteristics, and ideal electrode characteristics were appeared especially in case of doping of the base electrolyte[potassium tetraphenylborate(TPB)]. The optimum carrier content was about 3.23 wt% in case of D18Cr6 and Val. DBP was best as a plasticizer. As membrane thickness decreased the impedance characteristics was improved, but electrode characteristics were lowered for membrane thickness below the optimum. In the case of D18Cr6, the selectivity coefficients by the mixed solution method for the $K^+$ ion were the order of $NH_4{^+}>Ca^{2+}>Mg^{2+}>Na^+$.

• Journal of the Korean Vacuum Society
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• v.15 no.4
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• pp.395-403
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• 2006

It is known that $MgAl_2O_4$ has higher resistance to moisture than MgO, in humid ambient MgO is chemically unstable. It reacts very easily with moisture in the air. In this study, the characteristic of $MgAl_2O_4$ and $MgAl_2O_4/MgO$ layers as dielectric protection layers for AC- PDP (Plasma Display Panel) have been investigated and analysed in comparison for conventional MgO layers. MgO and $MgAl_2O_4$ films both with a thickness of $1000\AA$ and $MgAl_2O_4/MgO$ film with a thickness of $200/800\AA$ were grown on the Cu substrates using the electron beam evaporation. $1000\AA$ thick aluminium layers were deposited on the protective layers in order to avoid the charging effect of $Ga^+$ ion beam while the focused ion beam(FIB) is being used. We obtained sputtering yieds for the MgO, $MgAl_2O_4$ and $MgAl_2O_4/MgO$ films using the FIB system. $MgAl_2O_4/MgO$ protective layers have been found th show $24{\sim}30%$ lower sputtering yield values from 0.244 up to 0.357 than MgO layers with the values from 0.364 up to 0.449 for irradiated $Ga^+$ ion beam with energies ranged from 10 kV to 14 kV. And $MgAl_2O_4$ layers have been found to show lowest sputtering yield values from 0.88 up to 0.109. Secondary electron emission coefficient(g) using the ${\gamma}$- FIB. $MgAl_2O_4/MgO$ and MgO have been found to have similar g values from 0.09 up to 0.12 for indicated $Ne^+$ ion with energies ranged from 50 V to 200 V. Observed images for the surfaces of MgO and $MgAl_2O_4/MgO$ protective layers, after discharge degradation process for 72 hours by SEM and AFM. It is found that $MgAl_2O_4/MgO$ protective layer has superior hardness and degradation resistance properties to MgO protective layer.

• Tunnel and Underground Space
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• v.15 no.1 s.54
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• pp.1-8
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• 2005

Measurement of convergence was/is carried out manually throughout the world for tunnels under construction. However, manual method has certain limitations in terms of applicability for the tunnels in operation. This paper describes state of the art of convergence monitoring systems which are available for measuring displacement of existing tunnels. These technologies are analyzed as follows: 1 The Sofo system using the fiber optic sensors has been applied to the stress measurement of the tunnel lining. It has not yet been used for the monitoring of tunnel convergence because of its cost and reliability 2. A TPMS(Tunnel Profile Monitoring System) using tilt sensors and displacement sensors is used for the convergence monitoring of highway tunnels, subway tunnels and underground ducts. 3. A BCS(Bassett Convergence System) using a pair of tilt sensors can be used for the convergence monitoring of tunnels, however the accuracy of the measurement has to be improved because it uses AC input voltage during data acquisition. The system has to be validated before it can be applied to the tunnels in operation. Convergence monitoring systems using TPMS and/or BCS are recommended to be evaluated and improved by a series or tests in tunnels under construction in order to be applied to the main measuring section and the tunnels in operation.