• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.987-990
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• 1999

본 연구에서는 $BaTiO_3$를 기본 조성으로 하여 PTC 써미스터를 제조하였으며 여기에 첨가제로서 Ca, Mn, Nb의 양을 순차적으로 변화시켜 미세구조 및 전기적 특성을 연구하였다. 또한 복소 임피던스 측정을 통해서 PTC 효과에 미치는 주 저항 성분에 대해서 고찰하였다. Ca 첨가 실험에서는 5[mol%] 첨가된 시편에서 $2.3{\times}10^7[\Omega{\cdot}cm]$의 높은 peak 비저항이 나왔으며 Mn과 Nb에서는 각각 0.1[mol%], 0.2[mol%]에서 $1.5{\times}10^8[\Omega{\cdot}cm]$와 $3.71{\times}10^9[\Omega{\cdot}cm]$의 수치가 측정되었다. 또한 Nb 첨가 실험에서는 첨가량이 증가할수록 결정립의 크기가 조밀해지는 현상을 보였다. PTC 효과에 미치는 주 저항 요소에 대해서 관찰한 복소 임피던스 측정에서는 결정립계 저항 성분이 주가 됨을 확인 하였다.

• Korean Journal of Breeding Science
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• v.43 no.1
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• pp.56-61
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• 2011

Brown planthopper(BPH) is one of the most destructive insect pests of rice. The use of genetically resistant cultivars has proven to be a more economical, efficient and environment friendly means to combat this pest. This study was carried out to investigate the relationship between BPH resistant gene, Bph18 and yield components of rice using DH(doubled haploid) lines derived from 'Saenuri'/SR30071-3-7-23-6-1-1-1. SR30071-3-7-23-6-1-1-1 line has Bph18 gene derived from wild species, Oryza australiensis. BPH resistant gene, Bph18 shortened heading days, enlarged culm length and panicle length and reduced ratio of ripened grains of rice. The results indicate that backcrossing breeding is necessary to develop elite cultivars carrying Bph18 gene.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.8
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• pp.39-48
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• 2016

In this paper, we propose thermal resistance compact model of FinFET structure that has hexagon shaped source/drain. The heating effect and thermal properties were increased by reduced size of the device, and thermal resistance is an important factor to analyze the effect and the properties. The heat source and each contact that is moved heat out were set up in transistor, and domain is divided by the heat source and the four parts of contacts : source, drain, gate, substrate. Each contact thermal resistance model is subdivided as a easily interpretable structure by analyzing the temperature and heat flow of the TCAD simulation results. The domains are modeled based on an integration or conformal mapping method through the structure parameters according to its structure. First modeled by analyzing the thermal resistance to a single fin, and applying the change in the parameter of the channel increases to improve the accuracy of the thermal resistance model of the multi-fin/ finger. The proposed thermal resistance model was compared to the thermal resistance by analyzing results of the 3D Technology CAD simulations, and the proposed total thermal resistance model has an error of 3 % less in single and multi-finl. The proposed thermal resistance model can predict the thermal resistance due to the increase of the fin / finger, and the circuit characteristics can be improved by calculating the self-heating effect and thermal characterization.

• 한국초전도학회:학술대회논문집
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• v.9
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• pp.343-347
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• 1999

We fabricated a resistive SFCL having a shunt resistor parallel to it in order to bifurcate the transient current at faults. The SFCL consists of a YBCO film coated with an Au layer (10 ${\omega}$ at room temperature), which is to disperse the heat generated at hot spots in the YBCO film, and the 5 ${\omega}$ shunt resistor. The minimum quench current of the SFCL was found to be 12.2 A$_{peak}$. This SFCL successfully controlled the fault current below 23 A$_{peak}$ which is otherwise to increase up to 113 A$_{peak}$. Bifurcation of the current resulted in the temperature rise of the YBCO/Au film 3 times slower than without the shunt, protecting the SFCL at high currents.

• Korean journal of applied entomology
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• v.35 no.3
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• pp.260-265
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• 1996

A field colony of the two-spotted spider mite, Tetranychus urticae Koch, was selected with tetradifon for 4 mousing whole-plant residual method. This strain showed 371-fold resistance to tetradifon. The log dosehatchability lines of $F_{1}$ eggs(RS cross; Td5female$\times$Smale, and SR cross; Sfemale$\times$Td5male) were closer to the line of the resistant colony than to that of the susceptible. These differences could be due to cytoplasmic inheritance or maternal effect. The estimate of dominance index (D) for the $F_{1}$ eggs of RS cross was 0.998 and that for $F_{1}$ eggs of SR cross was 0.262. This indicates that tetradifon resistance is completely dominant in RS cross and incompletely dominant in SR cross. Td5 strain exhibited high levels of resistance to clofentezine, benzoximate, and chlorfencon, and no cross resistance to fenazaquin, pyridaben, flufenoxuron, tebufenpyrad, and fenothiocarb.

• The Journal of Engineering Geology
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• v.31 no.2
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• pp.187-197
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• 2021

Clay mineral content of weathered zone is a key parameter for landslide studies. Electrical resistivity tomography is usually performed to delineate the geometry of complex landslides and to identify the sliding surface. In clay-bearing weathered zone, parallel resistivity Archie equation is employed to investigate the effect of conductivity added (resistivity reduced) by clay minerals of kaolinite and montmorillonite, which is dependent on their specific surface area and cation exchange capacities (CEC). A decrease of overall resistivity and apparent formation factor is observed with increasing pore-water resistivity, significantly in montmorillonite. Formation factor is found decreased with increasing porosity and decreasing cementation factor. Parallel Archie equation was applied to the electrical resistivity data from the test area (Sinjindo-ri, Taean-gun, Chungcheongnam-do, Korea) which experienced land creeping in the year of 2014. A panel test with varying clay-mineral contents provides the best fit section when the theoretical section constructed with the assumed contents approaches the field section, from which the clay-mineral content of the weathered zone is estimated to be approximately 10%. Resistivity interpretation schemes including the clay mineral contents for land creeping studies explored in this paper can be challenged more when porosity, saturation, and pore-water resistivity are provided and they are included in the numerical resistivity modeling.

• Journal of International Area Studies (JIAS)
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• v.15 no.1
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• pp.61-82
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• 2011

Public resistance is an essential factor of the democratization process. Due to this, public resistance has been recognized as an important element in discussing the democratization of China. Recently in China, and a new era of resistance especially the agrarian resistance has been being expanded. This paper identifies trends and characteristics of that. With searching changes in the relationship between the nation and the societies in China, we will check whether democratization can be built from the whole bottom of the nation's ideology or not. It is a paradox of china's economic growth that the peasant uprising increased is a factor to the growth. The farmers' smoldering discontent exploded with rage because rural communities have been forced to sacrifice during the growth. The authoritarian party-state system in China has been faced with the limits in calming the peasant revolt down with the traditional suppression and restriction. Even though the party-state system in China has accepted farmers' dissatisfaction somewhat, and it has tried to improve its image of a benevolent government and pursued buying stability strategy, the gap between urban and rural areas has been expanded in the sustainable economic development and modernization process, therefore the authorities could not soothe the farmers' sense of alienation. Accordingly, the peasant revolt has not flickered out easily, and has been getting uncontrolled across China. Resistance characteristics of Chinese farmers have also changed. In the past, they had been sporadic and indirect ways, whereas in recent years, they have changed into organized and active ways. Of course, it is generally evaluated that the party-state system has sustained a strong social control so far. Buying stability strategy has prevented farmers' complaints from spreading to a threat to its regime, because civil societies in rural areas have still weak foundations from being formed. The party-state system, because of tensions and conflicts, will control the growing powers of civil societies in rural areas with institutionalization of interaction between the nation and the societies, and they will induce street protests to legalized struggle for a while. However, the relationship between the state and the societies has already started new rearrangement, in terms of that the conflicts between the state and rural communities have continued, and the changes of resistance ways.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.913-915
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• 2001

본 논문에서는 유한 요소법을 압전체에 적용하여 계산한 임피던스 파형을 실험적으로 검증하였으며 이를 압전 변압기에 적용하여 압전 변압기의 공진 특성 즉 입력측에서의 전기적인 임피던스 및 출력측에서의 전기적인 임피던스를 해석하였다. 또한 압전 변압기의 공진 모드를 나타내는 어드미턴스 궤적을 이용한 압전 변압기의 등가 회로 정수의 계산을 통해 등가 회로를 구성하였으며 무 부하시의 승압비를 계산하였다. 등가 회로를 이용하여 계산된 승압비의 결과를 유한 요소법을 이용한 결과와 비교하여 손실을 나타내는 등가 회로 정수(R)를 계산하였으며 유한 요소법에 의한 기계적인 진동 손실의 결과와 비교하여 계산된 저항(R)값의 타당성을 검증하였다.

• Journal of Ocean Engineering and Technology
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• v.29 no.2
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• pp.111-119
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• 2015

In the initial ship design stage, performance predictions are generally carried out before and after the hull form design. The former is based on the main dimensions and power information, and the latter is based on the geometry of the hull form and propeller. This paper deals with the practical application of neural networks for the prediction of a ship's performance factors before and after the hull form design. For this, the hull form parameters that affect the performance are studied, and an optimal neural network structure based on the SSMB database is constructed. By comparing the results predicted by neural networks and the model test results, we confirmed that neural networks can be applied to practically evaluate the performance in the initial ship design stage.

• Journal of the Korean Geosynthetics Society
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• v.18 no.2
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• pp.11-21
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• 2019

This paper describes the applicability of FEA(Finite Element Analysis) to the simulation of pile pullout behavior under various soil conditions (relative density and fines content), in order to evaluate reasonably the pullout resistance of pile. That is, the results of previous research (You et al., 2018) were analyzed by FEA under the same conditions. The FEA results showed that axisymmetric analysis using virtual ground was able to evaluate the skin friction of the pile. Also, axisymmetric analysis, which can apply the shear resistance characteristics of the pile-soil interface in various soil conditions, could be used as an analytical method that can simulate a reasonable pile pullout behavior. Therefore, the analytical model proposed in this study was able to simulate appropriately the pullout behavior based on the stress-strain relationship of the pile-soil interface.