• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2002.07a
• /
• pp.296-300
• /
• 2002

Thin films of Hydrogenated amorphous carbon(a-C:H) are generally exhibited by high electrical resistivities from 10$^2$ to 10$\^$16/ Ω$.$cm, resulting in an interesting material for high power, high temperature MIS devices applications. The hydrogenated amorphous carbon(a-C:H) films were deposited on silicon and glass using an rf plasma enhanced CVD method. The resultant film properties were evaluated in the respect of material based on r.f. power variation. The hydrogenated amorphous carbon(a-C:H) films of thickness ranging from 30 to 50 m were deposited at the pressure of 1 ton with the mixture of methane and hydrogen. We have used rf-IR( courier transform IR) and AFM(Atomic force microscopy) for determining physical properties and current-voltage(I-V) measurement for electrical Properties.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.27 no.7
• /
• pp.458-461
• /
• 2014

TiC thin films were deposited on Si wafer by unbalanced magnetron sputtering (UBMS) system with two targets of graphite and titanium. During the TiC sputtering, the RF power was varied from 100 W to 175 W and the physical and electrical properties of TiC films were investigated. The hardness and rms surface roughness of TiC films were improved with increasing RF power and the maximum hardness about 24 GPa and the minimum rms surface roughness about 1.2 nm were obtained. The resistivity of TiC films was decreased with increasing RF power. Consequently, the physical and electrical properties of TiC film wewe improved with increasing RF power.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.28 no.11
• /
• pp.694-697
• /
• 2015

We investigated the characterizations of carbon films fabricated by dual magnetron sputtering under various RF powers for the improvement of physical properties in carbon fiber (CF). All sputtered carbon films exhibited amorphous structure, regardless of RF powers, resulting in uniform and smooth surfaces. The hardness and elastic modulus are increased with the increase of RF power, and the adhesion and friction properties of carbon films were improved with the increase of RF power. In the results, The increase of RF power in the sputtering method improved tribological properties of the carbon films, and these attributes can be expected to improve the physical properties of the carbon fiber reinforcement plastics.

• International Journal of Contents
• /
• v.5 no.4
• /
• pp.35-39
• /
• 2009

The purpose of this study was to evaluate the changes in skeletal muscle architecture and qualitative properties by muscle contraction force when neuromuscular electrical stimulation (NMES) of 50% MVIC was applied. Sixteen subjects (8 male, 8 female) without neuromuscular disease volunteered to participate in the study. All subjects were divided into two subgroups: control (no electrical stimulation) group and 50% maximal voluntary isometric contraction (MVIC) group. NMES training program was performed in the calf muscle three times a week for 10 weeks. Before and after the experiments, the MVIC of ankle plantar flexor was measured by the use of dynamometer, and the ultrasonography in the gastrocnemius medialis muscle was measured. The following results were obtained; MVIC was significantly increased in the electrical stimulation groups. Pennation angle, muscle density, and white area index also considerably changed in the electrical stimulation groups. In conclusion, the NMES training of 50% MVIC, comparative low level, improved the skeletal muscle architecture and the qualitative properties as well as the muscle contraction force.

• Proceedings of the KIEE Conference
• /
• 1998.07d
• /
• pp.1416-1418
• /
• 1998

In this paper, the physical and electrical conduction properties due to the electron beam irradiation for low density polyethylene using insulating materials of the distribution cable and ultra-high voltage cable are studied. In FTIR spectrum for physical properties, the strong absorptions by methyl groups in wavenumbers 720[$cm^{-l}$] and 1463[$cm^{-l}$] are observed, and the effect by residual carbonyl groups (C = 0) is hardly appeared. So, as a result of the electrical conduction properties, it is confirmed that the conduction current is increased nearly to 50[$^{\circ}C$], and is not changed until the crystalline melting point from the temperature over 60[$^{\circ}C$] because of the defects of morphology and the formation of many trap centers by means of electron beam irradiation.

• Journal of the Korean Ceramic Society
• /
• v.37 no.7
• /
• pp.645-650
• /
• 2000

Effects of the chemical composition and sintering atmosphere on the formation of reaction phases and physical properties of reactive hot-pressed TiB2-AlN-BN composites were investigated. At N2 atmosphere, TiN was formed by the reaction between Ti and N2, which inhibited the densification and results in inferior mechanical-and electrical properties of the composites. However, at Ar atmosphere, enhanced densification and physical properties of composites were obtained due to that the TiN formation reaction was excluded. Densification of the composites was also hindered by BN, therefore, inferior mechanical-and electrical properties of composites were obtained with amount of BN in the starting materials. At Ar atmosphere, TiB2-AlN-BN composites having 318 MPa of flexural strength, 3.5 MPa.m1/2 of fracture toughness and 276$\mu$Ω.cm of electrical resistivity were fabricated from mole ratio 1:2:1.6 of Ti-Al-BN mixtures.

• Carbon letters
• /
• v.14 no.1
• /
• pp.40-44
• /
• 2013

The bipolar plate is the most important and most costly component of proton exchange membrane fuel cells. The development of a suitable low density bipolar plate is scientifically and technically challenging due to the need to maintain high electrical conductivity and mechanical properties. Here, bipolar plates were developed from different particle sizes of natural and expanded graphite with phenolic resin as a polymeric matrix. It was observed that the particle size of the reinforcement significantly influences the mechanical and electrical properties of a composite bipolar plate. The composite bipolar plate based on expanded graphite gives the desired mechanical and electrical properties as per the US Department of Energy target, with a bulk density of 1.55 $g.cm^{-3}$ as compared to that of ~1.87 $g.cm^{-3}$ for a composite plate based on natural graphite (NG). Although the bulk density of the expanded-graphite-based composite plate is ~20% less than that of the NG-based plate, the I-V performance of the expanded graphite plate is superior to that of the NG plate as a consequence of the higher conductivity. The expanded graphite plate can thus be used as an electromagnetic interference shielding material.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.11 no.2
• /
• pp.162-166
• /
• 1998

Synthetic fluid, class 7 group 2, as an insulating and cooling material is selected as. specimen, arid it is studied for the physical and electrical properties. Also, Benzotriazole(following as BT A) known as a suppressant of streaming electrification is added to it, and the change of physical and electrical properties by addition of BT A is investigated. From the spectrum of FT-IR, it is confirmed that the absorption peak in wavenumbers $3400{\sim}3450[cm^{-1}]$ is small or disappears when BTA is added. AC breakdown strength and volume resistivity of each specimen are investigated. It is considered that the effective content of BTA is about 10[ppm] for the suppression of electrification in this experiment.

• Fashion & Textile Research Journal
• /
• v.11 no.4
• /
• pp.641-647
• /
• 2009

The purpose of this study was to evaluate the physical properties and handle of knitwears made with silver yarns. The four different knitted fabrics were made and compared: cotton(C), cotton/silver(CS), polyester(P), and polyester/silver(PS). If fabrics knitted with silver combined yarns, their electrical shield properties, UV-cut properties, anti-static properties, and air permeability were improved. As an additional effect this also improves the antibacterial properties of fabrics. It was found that overall physical properties and functional properties were improved by using silver yarn with cotton. The silver knitted fabric was found to be improved its softness and fullness hand for apparel.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.31 no.1
• /
• pp.40-43
• /
• 2018

Various Ni-doped carbon (C : Ni) thin films were fabricated using different Ni target power densities by unbalanced magnetron sputtering (UBM). The effects of target power density on the structural, physical, surface, and electrical properties of C : Ni films were investigated. The UBM C : Ni thin films exhibited uniformly smooth surfaces. The rms surface roughness and friction coefficient values of the C : Ni films decreased with the increase in target power density. The physical properties of the films such as hardness and elastic moduli increased while their electrical properties such as resistivity decreased with the increase in the target power density. These results show that an increase of the power density leads to an increase in the proportion of Ni and nanocrystallization of the amorphous carbon film; this contributes to the changes observed in the physical and electrical characteristics.