• The Plant Pathology Journal
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• 제34권1호
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• pp.71-77
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• 2018

Resistance to Tomato spotted wilt virus isolated from paprika (TSWV-Pap) was overcome at high temperatures ($30{\pm}2^{\circ}C$) in both accessions of Capsicum annuum S3669 (Hana Seed Company) and C. chinense PI15225 (AVRDC Vegetable Genetic Resources). S3669 and PI15225, which carrying the Tsw gene, were mechanically inoculated with TSWV-Pap, and then maintained in growth chambers at temperatures ranging from $15{\pm}2^{\circ}C$ to $30{\pm}2^{\circ}C$ (in $5^{\circ}C$ increments). Seven days post inoculation (dpi), a hypersensitivity reaction (HR) was induced in inoculated leaves of PI152225 and S3669 plants maintained at $25{\pm}2^{\circ}C$. Meanwhile, necrotic spots were formed in upper leaves of 33% of PI15225 plants maintained at $30{\pm}2^{\circ}C$, while systemic mottle symptoms developed in 50% of S3669 plants inoculated. By 15 dpi, 25% of S3669 plants had recovered from systemic mottling induced at $30{\pm}2^{\circ}C$. These results demonstrated that resistance to TSWV-Pap can be overcome at higher temperatures in both C. chinense and C. annuum. This is the first study reporting the determination of temperatures at which TSWV resistance is overcome in a C. annuum genetic resource expressing the Tsw gene. Our results indicated that TSWV resistance shown from pepper plants possess the Tsw gene could be overcome at high temperature. Thus, breeders should conduct evaluation of TSWV resistance in pepper cultivars at higher temperature than $30^{\circ}C$ (constant temperature).

• 한국안전학회지
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• 제28권2호
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• pp.14-20
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• 2013

All most of floors can become less slip resistant with wear. The deterioration of slip resistance can often occur rapidly. So relatively new products can become hazardous within a short period of time. The main objective of this study was the comparison of slip resistance variations caused by traffic wear and accelerative wear. The second objective was to ascertain the effect of wear, and to find out the causes of slip resistance change. Although statistical differences were observed between results of traffic wear and accelerative wear, the trend of the variations of slip resistance caused by traffic wear and accelerative wear was very similar. The measured slip resistance of tested floor changed up to 29%(and 26.5%) after 100,000 steps(and 750 cycles). As the traffic wear and accelerative wear were progressed, the surface roughness of the tested floor became smoother, and so the floor became more slippery under the wet condition. The abraded(worn out) floor surface tended to become hydrophilic surface, while the new floor surface tended to show hydrophobic nature. This phenomenon would change the wettability of floor surface, and the wettability would affect the variation of slip resistance.

• 경영정보학연구
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• 제11권3호
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• pp.125-146
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• 2009

우수한 이점들을 갖춘 오픈소스 소프트웨어(OSS)의 출현은 많은 사람들에게 상당한 흥미를 불러일으켰다. 대표적인 OSS로 알려진 리눅스(Linux)에 관한 연구에서 보편적인 방법으로 개발할 경우, 약 54억 유로의 비용이 들고, 연 73,000명의 개발자들이 필요할 것이라고 추정하였다. 그러나 리눅스는 개인사용자들을 위한 운영체제 시장 점유의 0.65퍼센트만을 차지하고 있었고 이는 마이크로소프트 윈도우즈 제품이 전체의 90퍼센트를 차지하는 것과 대조적인 것이었다. OSS의 개발에 사용된 대부분의 노력들이 낭비되거나, 잠재적인 가치가 실제적으로 사용자들에게는 의미 없게 되는 결과였다. OSS의 채택은 현재의 소프트웨어의 사용을 중단함과 동시에 새로운 소프트웨어로 변경(전환)하는 것이다. 만약 사용자들이 전환하기를 주저한다면, OSS를 채택할 수 없을 것이다. 본 연구에서는 리눅스 사례를 활용하여 현재 사용하고 있는 상업성의 운영체제를 무료 운영체제(오픈소스 소프트웨어)로 전환하는 것에 대한 사용자 저항을 조사하였다. 본 연구는 전환비용을 6개의 세부유형(불확실 비용, 감정비용, 설치비용, 학습비용, 이익 손실 비용, 매몰비용)으로 분류하고, 201명의 사용자들을 대상으로 한 설문결과를 바탕으로 변화에 대한 사용자 저항에 미치는 영향을 조사하였다. 조사 결과, 변화에 대한 사용자 저항은 OSS의 채택의도에 부정적인 영향을 주는 것으로 확인되었다. 또한 본 연구는 불확실 비용과 감정비용이 변화에 대한 사용자 저항에 유의한 영향을 미치는 것으로 조사되었다. 기술 수용에 관한 선행연구들을 뛰어넘어, 본 연구는 전환비용이 변화에 대한 사용자 저항에 영향을 미치는 것을 이해하는데 공헌하고, OSS의 채택을 향상시키기 위한 전략을 개발하는 OSS 주창자들에게 제언하는데 의미가 있다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1381-1384
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• 2005

In these days, the piezoresistive material has been applied to various sensors in order to measure the change of physical quantities. But the relationship between the sensitivity of a sensor and the position and size of piezoresistor has rarely been studied. Therefore, this paper was focused on the distribution of the resistance change ratio on the diaphragm and bridge surface where piezoresistor would be formed, and proposed the proper size and position of piezoresistor with which the sensitivity of sensor was increased. As the width of mass and boss was increased, the distance between piezoresistors was closed and the maximum value of resistance change ratio was decreased by the increase of the structure stiffness. And according to the increment of seismic mass size, the value of resistance change ratio is decreased by increase of the structure stiffness. Y directional piezoresistor is formed in the position of $100\mu{m}\;apart\;from\;cantilever\;edge\;and\;length\;of\;that\;is\;800\mu{m}$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.69-70
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• 2006

A detailed Investigation of cell structure and electrical characteristic in chalcogenide-based phase-change random access memory(PRAM) devices is presented. We used compound of Ge-Sb-Te material for phase-change cell. A novel bottom electrode structure and manufacture are described. We used heat radiator structure for improved reset characteristic. A resistance change measurement is performed on the test chip. From the resistance change, we could observe faster reset characteristic.

• International Journal of Naval Architecture and Ocean Engineering
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• 제7권1호
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• pp.195-211
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• 2015

Flat plate friction lines have been used in the process to estimate speed performance of full-scale ships in model tests. The results of the previous studies showed considerable differences in determining form factors depending on changes in plate friction lines and Reynolds numbers. These differences had a great influence on estimation of speed performance of full-scale ships. This study was conducted in two parts. In the first part, the scale effect of the form factor depending on change in the Reynolds number was studied based on CFD, in connection with three kinds of friction resistance curves: the ITTC-1957, the curve proposed by Grigson (1993; 1996), and the curve developed by Katsui et al. (2005). In the second part, change in the form factor by three kinds of friction resistance curves was investtigated based on model tests, and then the brake power and the revolution that were finally determined by expansion processes of full-scale ships. When three kinds of friction resistance curves were applied to each kind of ships, these were investigated: differences between resistance and self-propulsion components induced in the expansion processes of full-scale ships, correlation of effects between these components, and tendency of each kind of ships. Finally, what friction resistance curve was well consistent with results of test operation was examined per each kind of ships.

• 한국수소및신에너지학회논문집
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• 제16권4호
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• pp.386-390
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• 2005

Al film(135.5 nm thick) with Pd film(39.6 nm thick) on the top of it was made by thermal evaporation method. Electrical resistance change due to hydrogen absorption and desorption was measured by four point measurement method. The sample was activated by hydrogen absorption and desorption cycling at room temp. Hydrogen was introduced into the film by increasing hydrogen gas pressure step by step up to 640 torr at room temp. The resistance change ratio was decreased to 12 % with increasing hydrogen pressure in contrast to normal metal behavior. This strange tendency was not understood yet. Further study is needed to find out the mechanism of hydrogen absorption in Al in Al/Pd film.

• Carbon letters
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• 제5권1호
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• pp.18-22
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• 2004

The failure behaviours of unidirectional pultruded carbon fiber reinforced polymer (CFRP) composites were monitored by the electrical resistance measurement during tensile loading, three-point-bending, interlaminar shear loading. The tensile failure behaviour of carbon fiber tows was also investigated by the electrical resistance measurement. Infrared thermography non-destructive evaluation was performed in real time during tensile test of CFRP composites to validate the change of microdamage in the materials. Experiment results demonstrated that the CFRP composites and carbon fiber tows were damaged by different damage mechinsms during tensile loading, for the CFRP composites, mainly being in the forms of matrix damage and the debonding between matrix and fibers, while for the carbon fiber tows, mainly being in the forms of fiber fracture. The correlation between the infrared thermographs and the change in the electrical resistance could be regarded as an evidence of the damage mechanisms of the CFRP composites. During three-point-bending loading, the main damage forms were the simultaneity fracture of matrix and fibers firstly, then matrix cracking and the debonding between matrix and fiber were carried out. This results can be shown in Fig. 9(a) and (b). During interlaminar shear loading, the change in the electrical resistance was related to the damage degree of interlaminar structure. Electrical resistance measurement was more sensitive to the damage behaviour of the CFRP composites than the stress/time curve.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권6호
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• pp.297-301
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• 2006

In the present work, we investigate the characteristics of new composition material, chalcogenide $Ge_1Se_1Te_2$ material in order to overcome the problems of conventional PRAM devices. The Tc of $Ge_1Se_1Te_2$ bulk was measured $231.503^{\circ}C$ with DSC analysis. For static DC test mode, at low voltage, two different resistances are observed. depending on the crystalline state of the phase-change resistor. In the first sweep, the as-deposited amorphous $Ge_1Se_1Te_2$ showed very high resistance. However when it reached the threshold voltage(about 11.8 V), the electrical resistance of device was drastically reduced through the formation of an electrically conducting path. The phase transition between the low conductive amorphous state and the high conductive crystal]me state was caused by the set and reset pulses respectively which fed through electrical signal. Set pulse has 4.3 V. 200 ns. then sample resistance is $80\sim100{\Omega}$. Reset pulse has 8.6 V 80 ns, then the sample resistance is $50{\sim}100K{\Omega}$. For such high resistance ratio of $R_{reset}/R_{set}$, we can expect high sensing margin reading the recorded data. We have confirmed that phase change properties of $Ge_1Se_1Te_2$ materials are closely related with the structure through the experiment of self-heating layers.

• 대한조선학회지
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• 제9권1호
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• pp.15-20
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• 1972

As the technique of resistance spot welding became more and more advanced the factors hitherto considered secondary become more and more important. Among these factors the distribution of heat and temperature during resistance spot welding is particularly important in conjunction with thermal stress, strain and residual stress, strain problems. The analytical investigations upon the transient temperature due to resistance spot welding were made for the carbon steel plate and aluminum alloy plate. The numerical values obtained by the analytical investigation are nearly identical with the temperature distribution which obtained by D.J. Sullivan and some other experimental data. It was thought therefore useful to estimate the heat effect upon the material such as a residual stress and strain, metalurgical change, change in physical properties and etc.