• Journal of the Microelectronics and Packaging Society
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• v.15 no.1
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• pp.27-31
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• 2008

Due to the increasing need for miniaturization of electronic device, embedded resistor technology using thick film resistance paste to embed resistors currently mounted on the board thus effectively reducing board size, is being extensively researched. In this research, thick film resistor paste having $0.35{\sim}4k{\Omega}/sq$ range of resistivity were fabricated using mixtures of carbon black and epoxy resin. In order to adjust the TCR (temperature coefficient resistivity), TCR modifiers such as Ni-Cr alloy, $SiO_2$ powder were added and were able to improve on TCR value with $100ppm/^{\circ}C$. Finally embedded resistor board using thick film resistance paste were fabricated. Stable resistivity value and reliability results were achieved.

• The Journal of the Korea Contents Association
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• v.21 no.5
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• pp.918-940
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• 2021

In this study, the concept of eXtended Reality Devices(XR) is defined, how it is applied by industry and how it will develop in the future, and based on the expanded integrated technology acceptance theory and innovation resistance, We tried to confirm through empirical analysis how the influencing variables affect. We carry out the analysis of the hypotheses using PLS Structural Equation Modeling. According to the empirical analysis results, this study confirms that innovativeness has a significant effect on UTAUT2's acceptance variables(performance expectation, effort expectation, hedonic motivation, price value) for XR devices, and these variables affect attitudes and acceptance of XR. and the pace of change of XR has a significant effect on perceived risk, and the perceived risk perceived by consumers mediates the pace of change and innovation resistance, and has a significant effect on innovation resistance. and innovation resistance to XR devices had a significant negative effect on acceptance. This study has its meaning because it found out that it deals expansively and comprehensively with personal innovation, the UTAUT2's acceptance variables, and the effects of perceived risk factors mediating the pace of change and resistance to innovation. In addition, it suggests that in order for innovative technologies such as XR to advance to the stage of market expansion, it is important to present strategies to reduce resistance to new technologies as much as the value to be provided to consumers.

• Journal of the Society of Naval Architects of Korea
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• v.37 no.3
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• pp.11-20
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• 2000

The flow characteristics around the stern region of two VLCCs with the same forebody and slightly different afterbody are investigated along with propulsive performance of the ship. The local mean flow measurements and the resistance and self-propulsion tests are carried out in the towing tank for the two VLCC hull forms. The measured results clearly show the formation of bilge vortices and their effect on propulsive efficiency. The comparisons are made for the two VLCC hull forms and the relation between stern framelines and bilge vortex strength is explored. Experimental data can provide a good test case to validate the accuracy of numerical methods and turbulence model of CFD codes for ship flow calculation.

• Korean Journal of Materials Research
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• v.7 no.10
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• pp.877-883
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• 1997

Ar 및 Ar과 $N_{2}$ 분위기하에서 rf 마그네트론 스퍼터링방법으로 Ta-AI과 Ta-AI-N합금막을 제조하였다. Ta-7.9at.% AI계열, Ta-26.7 at% AI게열과 Ta-45.4at.%AI계열에 Ar에 대한 질서유량비로 26%까지 질소를 첨가하여 Ta-AI-N박막을 증착한후, 300-$600^{\circ}C$온도 구산에서 열처리 전후의 구조 및 전기적 특성과 열적안정성을 통하여 레지스터의 적용가능성을 조사하였다. 구조 및 조성 분석은 X-선 회절과 Rutherford Backscattering Spectrometry(RBS)로 관찰하였고 열적안정성은 4단자법(four point probe method)을 이용한 저항변화를 통하여 측정하였다. 순수 Ta에 AI을 첨가하면 확장된 $\beta$($\beta$-Ta)N 합금박막에서 가장 열적안정성이 우수하게 나타났던 질소첨가 범위는 Ta $N_{hcp}$또는 TaN/ sub fcc/또는 Ta $N_{fcc}$와 비정질과의 혼합상순으로 상천이를 나타내었다. Ta-AI-N 합금박막에서 가장 열적안정성이 우수하게 나타났던 질서첨가 범위는 Ta-26.7at. % AI계열의 경우 19-36at.% $N_{2}$구간이었고, Ta-45.5at.% AI계열의 경우는 30-45at.%구간이었다. Ta-AI합금박막은 질소가 첨가되지 않아도 열처리 온도 및 시간에 따라 약 10% 이내의 비교적 작은 저항변화를 보여 열적안정성이 우수하지만 질소를 첨가하여 Ta-AI-N합금박막을 형성시킬경우, 증착된 상태에서 이미 큰 비저항을 나타내었고 열처리 동안 3%이내의 매우 작은 저항변화를 나타내었기 때문에 레지스터용 재료로써 열적안정성에 대한 잠재력이 크다.

• Fire Science and Engineering
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• v.30 no.6
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• pp.99-104
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• 2016

In animal and plant facilities, dust samples were collected from cattle sheds, pigsties and hen-houses, which have high proportion of electrical fires. The samples were diluted in distilled water and water resistivity was measured. Current measurements and tracking reappearance experiments were conducted using distilled water with dust samples. The analysis results were obtained to track the fire risks according to the dust resistivity. The highest value was the dust from cattle sheds followed in order by the dust of pigsties and hen-houses. In experiments measuring the temperature change and RMS current, the lower resistivity of water showed a significant trend of temperature and high amperage. In the tracking reappearance experiment with the lower resistivity water, the tracking speed was fast and the ignition time was shortened. This study investigated why each dust resistivity shows different results.

• The Journal of Engineering Geology
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• v.8 no.3
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• pp.235-245
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• 1998

Adquate friction resistance is needed to prevent pavement slipperiness and to allow vehicles to stop in a reasonable distance. Performance of the aggregates is reduced over time by wear and polishing as a consequence of vehicular traffic. In this research, the objective was to develop a laboratory method to test Indiana gravel aggregates to predict field performance, and determine causes for the range of values amang gravel aggregates. The assessment of gravel sources was primarily on the basis of individual rock types and those proportions comprising the gravel. Polish and friction values were determined in the laboratory with the British Wheel and Pendulum. The gravels of this study were composed primarily of carbonate aggregates that showed considerable variability in polishing thresholds. Igneous and metamorphic constituents polished to a lesser degree and are expected to improve overall aggregate performance. Estimates of the IFV (Initial Friction Value) and PV (Polished Value) for crushed gravel samples can be made based on the percentage of rock types present in the sample. A weighted average is used to make this calculation.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.4
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• pp.482-488
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• 2019

Leisure and business facilities have been steadily developing in Korea. Among waterborne leisure vessels and equipment, the distribution and sale of kayaks and canoes have significantly increased. Previously, (FRP) materials were primarily employed for constructing kayaks. However, owing to global warming and depletion of natural resources, the demand for non-polluting renewable energy is rapidly increasing, which has increased the demand for carbon fibers. To meet the requirements of changing social consciousness, a carbon fiber-based commercial kayak was designed in this study. Resistance analysis and structural safety were conducted by employing software tool for verifying the reliability of the proposed kayak. The pressure resistance and frictional resistance were examined in a wide range of speed. Obtained results indicate that at speeds greater than 2.6 m/s, the pressure resistance significantly increases and the total resistance also increases. Furthermore, the results corroborate that the proposed kayak structure has a adequate safety with respect to the design loads that are considered during operating conditions.

• Journal of the Microelectronics and Packaging Society
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• v.13 no.2 s.39
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• pp.15-19
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• 2006

The resistance switching characteristics of amorphous $SiO_2$ and poly-crystalline $TiO_2$ were investigated. Both films exhibit well defined switching characteristics with low and high resistance states. From I-V curve analyses, it was found that the low resistance states of both films obey an ohmic conduction mechanism and the high resistance states show generation of a Schottky potential barrier. Regarding the mechanism for resistance switching of the binary oxide, it is suggested that the generation and annihilation of potential barriers accounts for the changes to the high resistance state and low resistance state, respectively. The device operation characteristic parameters such as reset and set voltages of $TiO_2$ are distinctly smaller than those of $SiO_2$, indicating that the values are related to the dielectric constant.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.185-185
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• 2015

상용 AZ계열 마그네슘합금에 Ca을 첨가한 경우 발화저항성은 증가한 반면에 내식성은 감소하였다. 이에 비하여 Ca과 Y을 복합첨가한 경우에는 발화저항성 뿐만 아니라 내식성도 크게 향상되었다. 이는 합금원소의 종류 및 첨가량 변화에 따른 제2상의 종류와 분율의 변화 및 표면피막의 특성 변화에 기인한다.

• 전기의세계
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• v.41 no.3
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• pp.38-42
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• 1992

써미스터(THERMLISTOR)는 Thermally Sensitive Resistor의 약칭으로 온도변화에 대한 저항치의 변화가 극히 크게 변화하는 특징을 갖는 감온반도체이다. 이중에는 부특성 또는 NTC(Negative Temperature Coeffient) THERMISTOR와 정특성 또는 PTC(Positive Temperature Coeffient)THERMISTOR의 두종류와 NTC와 동일한 부의 온도계수이지만 어떤 온도영역에서 저항치가 급격히 감소하는 CTR로 분류한다. 이렇게 3가지 종류로 분류되는 THERMISTOR중 우리주변에서 가장 널리 보급되고 가정생활에서 실제로 흔히 볼수 있는 가전기기의 온도검출용 sensor로 많이 사용되고 있는 THERMISTOR SENSOR에 대해서만 기초지식을 알아보기로 하고 다음기회에는 응용기술에 대해서 알아보기로 하겠다.