• Proceedings of the KIEE Conference
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• 2007.04a
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• pp.258-260
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• 2007

Nowadays the automotive circuit design becomes more complicated a practical modern car circuit usually contains thousands of wires. So the error connection between connector and pins becomes more difficult to be located. This paper proposes a general way to locate all error wires in an automotive circuit design. Firstly, we give an exact definition of error wire to guide our job. This definition also composes the core part of our algorithm. Then we limit the area of the error wires by several steps. During these steps, we apply breadth-first search method to step over all wires under consideration of reducing time cost. In addition, we apply bidirectional stack technique to organize the data structure for algorithm optimization. This algorithm can get a result with all error wires and doubtful wires in a very efficient way. The analysis of this algorithm shows that the complexity is linear. We also discuss some possible improvement of this algorithm.

• Transactions of Materials Processing
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• v.17 no.2
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• pp.91-96
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• 2008

The governing parameters affecting the fatigue properties have been investigated experimentally in the high carbon steel wires with 0.94 wt.%C. In order to find the crucial factors, the advanced analysis techniques such as optical 3-D profiler, focused ion beam(FIB) and transmission electron microscope(TEM) were used. The two-type steel wires with different drawing strain were fabricated. The fatigue properties were measured by hunter rotating beam tester, specially designed for thin-sized steel wires. It was found that the fatigue properties of the steel wires with high drawing strain was higher than that with other wires because of low residual stress and high adhesion condition of brass coating layer.

• Journal of the Korean Society for Railway
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• v.7 no.1
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• pp.14-19
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• 2004

The effect of surface damage on fatigue properties of catenary wires were investigated to estimate their service lift. As surface defects of the wires caused by surface corrosion increase, surface roughness gets worse, and as roughness increases, it is easy for moisture coming from rain and dew to be condensed around uneven parts of the surface. The condensed moisture causes a locally severe corrosion which leads to damage of the wires. Corrosion of catenaty wires can make their actual lifetime shorter than that originally designed. The amount of decrease was more prominent as environmental conditions became more corrosive. They are also vibrated with some amplitude everytime pantographs touch contact line. The frequent cyclic load on the wire may result in a fatigue fracture. Surface damage by corrosion can make formation of crack initiation at fatigue. In the present study, the fatigue life of the used wire was measured 35 to 50% compared with that of new one in average.

• Progress in Superconductivity and Cryogenics
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• v.17 no.3
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• pp.37-40
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• 2015

Recently, the electrical insulation design for electrical apparatuses is important to cope with the tendency of high voltage. The degradation characteristics of a superconducting coil due to an electrical breakdown should be considered to design a high voltage superconducting coil. In this paper, the degradation characteristics of 2G high temperature superconducting (HTS) wires are studied with respect to electrical breakdown tests. To analyze the dependency of the degradation characteristics of 2G HTS wires, the electrical breakdown tests are performed with AC(alternating current) and DC(direct current) voltage. All tests are performed by applying various magnitudes of AC and DC breakdown voltages. To verify the degradation characteristics of 2G HTS wires, the tests are performed with various 2G HTS wires with respect to stabilizer materials. The degradation characteristics of 2G HTS wires, such as Ic(critical current) and index number are measured by performing electrical breakdown tests. It is found that the characteristics such as Ic and index number can be degraded by an electrical breakdown. Moreover, it is concluded that the degradation characteristics of 2G HTS wires are affected by the stabilizer material and applied voltages. The cross-sectional view of 2G HTS wires is observed by using a scanning electron microscope (SEM). As results, it is found that the degradation characteristics of 2G HTS wires are concerned with hardness and electrical conductivity of stabilizer layers.

• Journal of Korea Foundry Society
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• v.14 no.5
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• pp.455-463
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• 1994

Aluminum matrix composites reinforced by fine steel wires were fabricated by squeeze casting process. Preforms made of fine steel wires were prepared with different surface conditions, namely uncoated(TN), carbo-nitriding treated(TT), and brass coated(TA). Squeeze casting were performed under the pressure of $1500kg/cm^2$ for 3min. during solidification, and pouring temp. of the melt being $750^{\circ}C$ and the steel mold being preheated at $250^{\circ}C$. Microstructural characteristics were evaluated, particularly concerned with the effect of the surface conditions of the preforms. The results obtained from this study are like these. TN specimens show partially non-wetted regions, due to easy formation of oxides on the surface of the fine steel wires. TT specimens show no interfacial reaction between the steel wires and the aluminum alloy matrix, possibly due to the formation of carbo-nitrided zone on the surface of the steel wires. TA specimens show excellent wettabillity between the reinforced steel wires and the aluminum alloy matrix and very thin interfacial zone is formed between them. During the solution hardening treatment of TA specimens, thickness of the interfacial reaction zones were increased with the solution treating time. TA specimens show typical ductile fracture in tensile test, but TT specimens show brittle fracture possibly due to the formation of the brittle hard surface on the steel wires during carbo-nitriding treatments. TA specimens which were reinforced with 40 vol.% of the fine steel wires exhibit high tensile strength of $77.1kgf/mm^2$ and impact value of $8.1kgf-m/cm^2$.

• The Journal of Korean Academy of Prosthodontics
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• v.34 no.4
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• pp.823-832
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• 1996

The purpose of this study was to assess the effect of 1) the diameter(0.7,1.0,1.2mm) and number(1,2,3) of commonly available orthodontic metal wires embedded in self-curing orthodontic acrylic resin specimens($64{\times}10{\times}3mm$) and 2) the use of chemical adhesive system(Silicoater, Metalprimer) to prevent slipping at the interface between the resin and the metal wire on reinforcement by using three-point bending test. From this study, the following results were obtained. 1. No statistically significant difference was found among the transverse strengths for the control without reinforcement, one 0.7mm wire, two 0.7mm wires, three 0.7mm wires, and one 1.0mm wire groups(P>.05). 2. In the groups with 1.0 or 1.2mm wires, the transverse strength increased in proportion to the increase of number of wires(P<.05). 3. In the groups with 0.7 or 1.0mm wires, neither of Silicoater and Netalprimer increased the transverse strength significantly(P>.05). 4. No statistically significant difference was found in transverse strength between Silicoater groups and Metalprimer groups with same diameter of wires(P.>05). From these result, it is concluded that diameter of wires is a primary considering factor to reinforce the acrylic resin effectively and, when this requirement is satisfied, increased number of wires or chemical adhesive systems can be expected to produce the additional reinforcing effect.

• Fire Science and Engineering
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• v.24 no.4
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• pp.104-108
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• 2010

This paper describes electrical fire on electric pad using carbon type hot wires. A carbon type hot wires electric pad is virtually impossible to connect hot wire as a method of electrical welding or soldering. In order to connect between hot wires, that has to splice carbon type material connector. If junction of hot wires was occurrence of poor connection on electric pad, it increase contact resistance on this junction point. With increasing contact resistance, junction of hot wires on electric pad generates local heating and finally leads to electrical fire. In this paper, we analyzed shape of damage in hot wires caused by electrical local heating and investigated fire cause on electric pad using by carbon type hot wires.

• Advances in materials Research
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• v.1 no.1
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• pp.31-35
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• 2012

Unique tooth-like (milky white) color ${\beta}$-Ti dental arch wires are prepared by anodization in a 1M $H_2SO_4$ electrolyte at $30^{\circ}C$ and 30 V for 88 min and 40 s. Aggregates are formed on these surfaces of the anodized wires with tooth-like colors, and the results are different from those of the anodized wires with monochromatic colors which have smooth oxide surfaces. Similar to the monochromatic wires, the composition of the oxide layer is $TiO_{2-x}$ and the x approaches zero at the outer layer. But different from the amorphous structure observed in monochromatic wires, the oxide layers are partially crystallized with an anatase structure. The milky white colors result from the rough and crystalized oxide layers, not by the interference effect as observed in monochromatic wires.

• The korean journal of orthodontics
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• v.26 no.5 s.58
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• pp.591-599
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• 1996

This study was undertaken to investigate the cytotoxicity of orthodontic wires after doing various treatments to the wires. 018x025 inch Stainless steel(A) and Co-Cr(B) wires were used and each of them were divided into 4 groups. A-1 and B-1 groups were as received state, and A-2 and B-2 groups were heat treated. A-3 and B-3 groups were electropolished after heat treatment, and A-4 and B-4 groups were soldered with Ag-solder. Each group had 3 wires and these were sterilized with Ethylene Oxide gas. We used human gingival fibroblast cell culture and agar overlay technique to investigate the cytotoxicity of each group of wires. The cytotoxicity of wire was assessed using reaction index (zone index/lysis index). The findings of this study were as follows. 1. Both of the stainless steel wire and Co-Cr wire showed no cytotoxicity in as received state. 2. Heat treatment or electropolishing of the wires had no effect on the cytotoxicity of the wires 3. Soldered stainless steel wires showed a little wider zone of discoloration than soldered Co-Cr wires, but the zone index and cytotoxicity(reaction index) was not different. 4. Soldered wires showed moderate cytotoxicity in both of the wires.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.680-687
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• 2009

Several kinds of Electrical Wires have been used in Electric Multiple Units(EMU) for the supply of electric power, supervision, and the propagation of control signals. These Electrical Wires must be inspected for safe and stable operation of EMU. The degradation diagnosis to estimate the integrity of Electrical Wires has recently been requested according to the long use of EMU. This paper describes on application of diagnosis method for EMU.