• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.10
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• pp.1242-1251
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• 2011

This study investigates the effect of mixed characteristics of oily soil such as mixed ratio, polarity of oily soil on contact angle of fabric, removal of oily and particulate soil from PET fabric in oily/particulate soil mixed system. The contact angle of fabric in the surfactant solution with suspended oily soil was examined as a fundamental environment of detergency of soil from fabrics. Detergency was investigated as function of mixed ratios of oily/ particulate soil, type of oily soil, surfactants concentration, surfactant type and temperature of detergency in surfactant solution. The contact angle of fabric in surfactant solution sharply increased with mixing nonpolar oily soil; in addition, the contact angle slightly increased with increasing contents of oily soil and decreased with increasing surfactant concentration. The removal of oily and particulate soil from fabric was higher in the solution mixed with polar versus nonpolar oily soil. The detergency increased with increasing surfactant concentration and the increased temperature of surfactants solution that were relatively improved in NPE compared to DBS solutions, The results indicated that the detergency of oily and particulate soil showed a similar trend in oily/ particulate mixed soil systems. The general contact angle of fabric was well related with the detergency of oily and particulate soil in oily/particulate mixed soil system, therefore, the primary factor determining the detergency of soil in oily/particulate mixed soil system may be the contact angle of fabric caused by wettability.

• Journal of Haehwa Medicine
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• v.20 no.2
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• pp.125-131
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• 2012

The number of allergic contact dermatitis patients is steadily increasing but a proper reliability treatment guide is not prepared in Oriental Medicine. Also, the number of clinical cases on allergic contact dermatitis is not sufficient in Oriental medicine. As such, the facial flushing of allergic contact dermatitis which has been improved by infra-red therapy is significant in its treatment purpose. We reported on 43-year old male patient with allergic contact dermatitis. We treated him with herbal concoction, acupuncture, infra-red therapy and cupping therapy. We have received a good result in this case by using the combination of infra-red therapy. We reached a conclusion that using infra-red therapy can improve the facial flushing of patient with allergic contact dermatitis. However, further research on the effect of infra-red therapy for these symptoms is desired.

• Tribology and Lubricants
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• v.32 no.3
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• pp.88-94
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• 2016

We conduct a series of fretting corrosion tests on tin-coated electric contact to evaluate the effects of lubricant on fretting corrosion behavior. We perform these tests with a constant contact force at 25℃ 50℃, 75°C, and 100℃. In the tests with a span amplitude of 30 μm, we could not determine the conventional behavior of the first, second, and third stages of the change in electric resistance during fretting corrosion and observed that the contact resistance continuously increases with the cycles. This behavior is due to the fact that the generation of oxides on the tin-coated contact is controlled and stabilized by the presence of lubricant. SEM observations on samples with a span amplitude of 77 μm at all testing temperatures confirm that there is less oxide debris on the fretting damaged surface. Hence, for tin-coated electric connector, the effect of lubrication on the lifetime of the electric contact increases as the fretting span decreases and testing temperature increases, compared to those for connector without lubricant. Especially, for a specimen with a span amplitude of 30 μm at 100℃, the increment in contact lifetime due to lubricant is found to be more than 20 times, compared to that without lubricant.

• Journal of IKEEE
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• v.25 no.3
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• pp.467-472
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• 2021

Stable operation of semiconductor devices is needed even at high temperatures. Among the structures of semiconductor devices, the area that can cause unstable electrical responses at high temperatures is the contact layer between the metal and the semiconductor. In this study, the effect of annealing conditions included in the process of forming a contact layer of nickel silicide(NiSix) on a p-type SiC layer on the specific contact resistance of the contact layer and the total resistance between the metal and the semiconductor was investigated. To this end, a series of electrodes for TLM (transfer length method) measurements were patterned on the 4 inch p-type SiC layer under conditions of changing annealing temperature of 1700 and 1800 ℃ and annealing time of 30 and 60 minutes. As a result, it was confirmed that the annealing conditions affect the resistance of the contact layer and the electrical stability of the device.

• Journal of Ceramic Processing Research
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• v.19 no.5
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• pp.361-368
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• 2018

We investigated the interfacial properties of fluorocarbon self-assembled monolayers (FC-SAMs) with different alkyl chain lengths. It was found that the substrate characteristics were changed rapidly with the fabrication time and temperature of the SAM. FC-3SAM, which has the shortest alkyl chain in this study, showed a contact angle of $54.1^{\circ}$ when it was fabricated in an electric oven at $60^{\circ}C$ for the first minute. The FC-3SAM showed a contact angle of up to $76.9^{\circ}$ when it was fabricated in an electric oven at the same temperature condition for 180 minutes. FC-10SAM, which has the longest alkyl chain in this study, showed a contact angle of $64.7^{\circ}$ when it was fabricated at a temperature condition of $60^{\circ}C$ for 1 minute, and a contact angle of $98.7^{\circ}C$ at a temperature condition of $60^{\circ}C$ for 180 minutes. It was found that the FC-10SAM shows an increased contact angle and hydrophobic properties due to a well-aligned molecular structure resulting from a strong van der Waals force. In contrast, the FC-3SAM shows a small contact angle due to the intermolecular disorder resulting from a weak van der Waals force. The average roughness of FC-SAMs was investigated using AFM. The surface roughness of FC-SAMs, which verifies the results of contact angle, was confirmed. At a fabrication time of 120 minutes, the FC-10SAM showed an improvement in average roughness by 62% compared to that of FC-3SAM due to its good alignment.

• Asia Marketing Journal
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• v.20 no.3
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• pp.83-103
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• 2018

The purpose of this research is to investigate the effect of customer-contact employees support on service recovery efforts. Service companies should try to prevent the service failure situation from occurring, but it is realistic that the service failure occurs due to the characteristics of the service. Service recovery efforts of service providers are important because effective responses to service failures can enhance customer satisfaction despite service failures. Social support for customer-contact employees needs to improve service recovery efforts. Specifically, this study focuses on the mediation roles of job burnout and customer orientation in relationship between social support for customer-contact employees and service recovery efforts. Social exchange theory was used as the theoretical underpinning of the research model. Based on reciprocity principle, this paper suppose that support for customer-contact employees and service recovery effort are a kind of social exchange relationship. Social supports for customer-contact employees are categorized into internal and external organization. Internal organization is POS(perceived organizational support) and external organization is customer support. The research model was tested with the data gathered from the flight attendants whose emotional labor intensity was relatively high and the service failure frequently occurred. As a result of analysis, social supports for customer-contact employees classified into organizational support, supervisor support, and customer support are found to have differential impacts on job burnout and customer orientation. It has been found that job burnout of service providers is negatively affecting service recovery efforts. On the other hand, customer orientation of service providers has a positive influence on service recovery efforts. Based on the results of the analysis, we provide practical implications for effective service recovery efforts in service failure situations, and suggest the theoretical implications to explain the process of service recovery effort. Finally, limitations of the study and directions for future research are suggested.

• Journal of the Microelectronics and Packaging Society
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• v.30 no.2
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• pp.60-64
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• 2023

In this study, the electrical contact resistance characteristics between graphene and metals, which is one of important factors for the performance of graphene-based devices, were compared. High-quality graphene was synthesized by chemical vapor deposition (CVD) method, and Al, Cu, Ni, and Ti as electrode materials were deposited on the graphene surface with equal thickness of 50 nm. The contact resistances of graphene transferred to SiO₂/Si substrates and metals were measured by the transfer length method (TLM), and the average contact resistances of Al, Cu, Ni, and Ti were found to be 345 Ω, 553 Ω, 110 Ω, and 174 Ω, respectively. It was found that Ni and Ti, which form chemical bonds with graphene, have relatively lower contact resistances compared to Al and Cu, which have physical adsorption properties. The results of this study on the electrical properties between graphene and metals are expected to contribute to the realization of high-performance graphene-based devices including electronics, optoelectronic devices, and sensors by forming low contact resistance with electrodes.

• Journal of The Korean Astronomical Society
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• v.49 no.3
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• pp.65-71
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• 2016

We obtain the first complete CCD light curves (LCs) of the contact binary AP UMi in the VRI bands and analyzed them by means of the PHOEBE code. A spotted model is applied to treat the asymmetry in the LCs. The LC morphology clearly shows the O'Connell effect and the solution shows an influence of star spots on both components. Such effect of star spots is common between the RS CVn and W UMa chromospherically active stars. Based on the obtained solution of the LCs we investigate the evolutionary state of the components and conclude that the system is a pre-intermediate contact binary (f = 0.29) with mass ratio q = 0.38, and it is an A-type W UMa system where the less massive secondary component is cooler than the more massive primary one.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.2
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• pp.274-282
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• 2007

Statement of problem: Main consideration was given to the stresses at the site of implant entry into the cortical bone at the alveolar crest. As a suspectible factor affecting the occurrence of stress concentrations, the contact angle between the implant and the alveolar crest bone was addressed. Purpose: The purpose of this study is to evaluate angles between the alveolar crest bone and the implant effect on the implant crestal area induced stresses using a finite element method. Material and methods: Cylindrically shaped, standard size ITI implants entering into alveolar crest with four different contact angles of 0, 15, 30, and 45 deg. with the long axis of the implant were axisymmetrically modelled. Alterations of stresses around the implants were computed and compared at the cervical cortical bone. Results and conclusion: The results demonstrated that regardless of the difference of the implant/alveolar crest bone contact angles, stress concentration occurred at the cervical bone and the angle differences led to insignificant variations in stress level.

• Physical Therapy Korea
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• v.18 no.2
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• pp.1-8
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• 2011

The purpose of this study was to investigate the effect of high heeled shoes with the total contact insert (TCI) on the frontal plane of the joints for the lower extremity during the gait. Ten healthy females voluntarily participated in this study and the height of the high heeled shoes was 7 cm. A three-dimensional motion analysis system (VICON) and force plates were used to analyze the movements of the joints for the lower extremities. The results were as follows: There were no significant differences for the angle value on the event of the gait cycle in the maximum eversion and inversion of the ankle joint, the varus and valgus of the knee joint, and the adduction and abduction of the hip joint (p>.05). But, there was a significant difference or the range of motion in the ankle joint (p<.05). The value of ankle and knee moment with a TCI was less than the value for no TCI. And there were significant differences for the moment value of the maximum inversion and eversion on the ankle joint and for the maximum varus and valgus on the knee joint (p<.05). Therefore, a TCI would be effective in stabilizing the joints of the lower extremities and increasing the balance of a body to reduce the injure from a fall during the gait.