• Korean Chemical Engineering Research
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• v.48 no.2
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• pp.172-177
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• 2010

This study reports the high-temperature oxidation kinetics, ASR(area specific resistance), and interfacial microstructure of metallic interconnects coated with conductive oxides in oxidation atmosphere at $800^{\circ}C$, The conductive material LSC($La_{0.8}Sr_{0.2}CoO_3$, prepared by Solid State Reaction) was coated on the Crofer22APU. The contact behavior of coating layer/metal substrate was increased by sandblast. The electrical conductivity of the LSC coated Crpfer22APU was measured by a DC two probe four wire method for 4000hr, in air at $800^{\circ}C$. Microstructure and composition of the coated layer interface were investigated by SEM/EDS. These results show that a coated LSC layer prevents the formation and growth of oxide scale such as $Cr_2O_3$ and enhances the long-term stability and electrical performance of metallic interconnects for SOFCs.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.1023-1026
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• 2006

There are some cases in trouble with monitoring emergency patient by existing electrode sensor in measuring instrument in home and hospital etc. And there are problem to measure because of coming down electrode in emergency car or vessel of shaking and fat, humidity of patient. In this study, it has designed band-type for patient to put on the breast easily and go around anywhere freely putting band electrode on his body. Gold has used as electrode material in this electrocardiogram because of its excellent electronic resistance peculiarity and no trouble with skin. And it is able to monitor multi-body-signal by additional design of periphery temperature. There are good results of body signal transmission in the breast or the rib, and get a little body signal in abdomen. We get a result it is better case of gold than usual electrode on signal detection, and know usual electrode was disposable, but we have more correct result from gold electrode sensor, being semi-permanent ana. great contact ability even if movement.

• Journal of the Korean Vacuum Society
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• v.20 no.6
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• pp.436-441
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• 2011

Metal coating with several nanometer thickness was applied on the carbon nanotubes (CNTs) in order to improve electron emission characteristics and emission reliability for the potential applications in the area of various electron sources and displays. CNTs were grown on the 2-nm thick Invar (52% Fe, 42% Ni, 6% Co alloy)-catalized Si substrate by using plasma-enhanced chemical vapor deposition at $450^{\circ}C$. In order to reduce the spatial density of densely packed CNTs, as-grown CNTs were partly etched back by $N_2$ plasma and subsequently coated with 5~150 nm thick Ti by a sputtering method. 5 nm thick Ti-coated CNTs produced four times higher emission current density at the electric field of 6 V/${\mu}m$ and much lower emission current fluctuation, compared with the as-grown CNTs. These improved emission properties are mainly due to not only the work function of Ti (4.3 eV) lower than that of pristine CNTs (5 eV), but also lower contact resistance and better adhesion between CNT emitters and substrate accomplished by Ti coating.

• Journal of the Microelectronics and Packaging Society
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• v.26 no.3
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• pp.75-80
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• 2019

Silicon solar cells have been widely used as a most promising renewable energy source due to eco-friendliness and high efficiency. As modules of silicon solar cells are connected in series for a practical electricity generation, a large voltage of 500-1,500 V is applied to the modules inevitably. Potential-induced degradation (PID), a deterioration of the efficiency and maximum power output by the continuously applied high voltage between the module frames and solar cells, has been regarded as the major cause that reduces the lifetime of silicon solar cells. In particular, the migration of the $Na^+$ ions from the front glass into Si through the anti-reflection coating and the accumulation of $Na^+$ ions at stacking faults inside Si have been reported as the reason of PID. In this research, the thickness effect of $SiO_x$ layer that can block the migration of $Na^+$ ions on the reduction of PID is investigated as it is incorporated between anti-reflection coating and p-n junction in p-type PERC solar cells. From the measurement of shunt resistance, efficiency, and maximum power output after the continuous application of 1,000 V for 96 hours, it is revealed that the thickness of $SiO_x$ layer should be larger than 7-8 nm to reduce PID effectively.

• Journal of the Korean Electrochemical Society
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• v.21 no.4
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• pp.80-87
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• 2018

Safety issues in Li-ion battery system have been prime concerns, as demands for power supply device applicable to wearable device, electrical vehicles and energy storage system have increased. To solve safety problems, promising strategy is to replace organic liquid electrolyte with non-flammable solid electrolyte, leading to the development of all-solid-state battery. However, relative low conductivity and high resistance from rigid solid-solid interface hinder a wide application of solid electrolyte. Composite electrolytes composed of organic and inorganic parts could be alternative solution, which in turn bring about the increase of conductivity and conformal contact at physically rough interfaces. In our study, composite electrolytes were prepared by combining poly(ethylene oxide)(PEO) and $Li_7La_3Zr_2O_{12}$ (LLZO). The crystallinity, morphology and electrochemical performances were investigated with the control of LLZO contents from 0 wt% to 50 wt%. From the results, it is concluded that optimum content and uniform dispersion of LLZO in polymer matrix are significant to improve overall conductivity of composite electrolyte.

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.538-543
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• 2018

Powdery mildew caused by Podosphaera xanthii is a disease in cucurbit crops especially in green house. The objective of this study was to determine the effect of alternative fungicide spraying system for control of powdery mildew disease. We selected four fungicides with different mode of action and made three treatment combinations of each fungicide in 2017. Pyraclostrobin-flutianyl-penthiopyrad treatment showed the highest control value (87%) while, pyraclostrobin-pyraclostrobin-pyraclostrobin treatment showed the lowest control value (32.5%). So it seemed like the treatment was not suitable for control of powdery mildew. In 2018, pyraclostrobin of pyraclostrobin-flutianyl-penthiopyrad was replaced to contact fungicide called iminoctadine-tris-albesilate and compared control effect of two treatments. Two of the treatments showed similar control value (87.0% for pyraclostrobin, 89.0% for iminoctadine-tris-albesilate). These two tests in 2017 and 2018 indicated that alternative treatment of different fungicides is essential for controlling of powdery mildew and inhibiting development of fungicide resistance.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.2
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• pp.93-106
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• 2021

In general, segment lining tunnel refers to a tunnel formed by connecting precast concrete segments as a ring and connecting such rings to each other in the longitudinal direction of the tunnel. As the structural properties of the segment lining is highly dependent on the behavior of the segment joints, thus correct modelling of joint behavior is crucial to understand and design the segment tunnel lining. When the tunnel is subjected to ground loads, the segment joint behaves like a hinge that resists rotation, and when the induced moment exceeds a certain limit of the rotation then it may enter into non-linear field. In understanding the effect of the segment joint on the lining behavior, a moment-rotation relationship of the segment joint was explored based on the Japanese practice and Janssen's approach commonly used in the actual design. This study also presents a method to determine the rotational stiffness of joint refer to the bearing strength. The rotation of the segment joint was estimated in virtual design conditions based on the existing models and the proposed method. And the sectional force of the segment lining and joint were calculated along with the estimated rotation. As the rotation at the segment joint increases, the joint contact area decreases, so the designer have to verify the segment joint for bearing strength as well. This paper suggests a consistent method to determine the rotational stiffness and bearing strength of joints.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.325-330
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• 2021

This study set out to investigate the forms, attributes, and escape methods of post-subjects projected on the investigator's works in connection with rhizomatic thinking proposed as a way of social transformation by Deleuze and Guattari and examine their social connotations. Post-subjects projected on the investigator's works are not completed wholes of some sort, but like materials whose constant premise is change and creation. In the investigator's works, post-subjects have conscious and unconscious desire. It is the desire of creation with positive attributes including Deleuze's and Guattari's pursuit of changes in a contradicting society. When desire is deployed in post-subjects, they will carry out an escape. This way of escape is rhizomatic proposed by Deleuze and Guattari. It deconstructs contradicting things and repeats connection, contact, and severance with the outside world, building a new order. Rhizomatic post-subjects appearing in the investigator's works depict the escape process and method in abstract ways through the variable installation of objets combined with a color field of repeating brushes. In this work, the goal of post-subjects is to make a safe landing in a space where beings are recognized for their values and free and creative lives. These post-subjects are nomads creating a new landscape continuously, wandering around vast plains, and also artists and literary figures resisting a contradicting society. That is, they are connected to the concept of a war machine proposed by Deleuze and Guattari as a concept of social transformation and to the concept of Nietzsche's Agon to devise and create new values and politics based on street passion. They seek after a space where they can co-exist with otherness recognized rather than the complete deconstruction of the old order.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.59-65
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• 2021

This is a case study on the use of Albert Camus' La Peste, which has gained its popularity in today's generation of post-COVID as well as the use of big data analysis tools for major and elective classes. First, we asked students majoring in French to compare the use of vocabulary and the number of appearances for characters using big data analysis, for about 400 pages of the original text. As a result, we were able to confirm a similar relationship between Camus' Absurdism and the vocabulary used within La Peste, in addition to noting the heavy frequency of resistant characters. Students in elective classes were asked to read the literature in a Korean-translated version to determine the frequency of vocabulary and characters' appearances. Students were able to strongly relate to La Peste due to its commonality between COVID and the plague in the literature. We also received high levels of class satisfaction regarding the use of big data analysis tools. The students showed a positive response both towards choosing La Peste as the work of literature and using big data, the main tool in the Fourth Industrial Evolution. We were able to identify good results even in a non-contact environment, as long as the literature does not rely on traditional methods but rather lectures to reflect current situations.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6D
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• pp.809-817
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• 2008

This paper deals with the development of ViscoElastic Continuum Damage Finite Element Program (VECD-FEP++) and its verification with the results from both field and laboratory accelerated pavement tests. Damage characteristics of asphalt concrete mixture have been defined by Schapery's work potential theory, and uniaxial constant crosshead rate tests were carried out to be used for damage model implementation. VECD-FEP++ predictions were compared with strain responses (longitudinal and transverse strains) under moving wheel loads running at different constant speeds. To this end, an asphalt pavement section (A5) of Korea Expressway Corporation Test Road (KECTR) instrumented with strain gauges were loaded with a dump truck. Also, a series of accelerated pavement fatigue tests have been conducted at pavement sections surfaced with four asphalt concrete mixtures (Dense-graded, SBS, Terpolymer, CR-TB). Planar strain responses were in good agreement with field measurements at base layers, whereas strains at both surface and intermediate layers were found different from simulation results due to the complexity of tire-road contact pressures. Finally, fatigue characteristics of four asphalt mixtures were reasonably described with VECD-FEP++.