• Title/Summary/Keyword: Scratching test

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Mechanical Damage Behavior of Single Crystalline Silicon by Scratching Test (Scratching Test에 의한 단결정 실리콘의 기계적 손상거동)

  • 김현호;정성민;이홍림
    • Journal of the Korean Ceramic Society
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    • v.40 no.1
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    • pp.104-108
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    • 2003
  • COF(Coefficient Of Friction), AE(Acoustic Emission), micro-cracks and crystal structure of the single crystalline silicon were investigated according to the induced normal load during scratching test. Scratching tests were performed with the loading rate of 100 N/min and various scratching speeds of 1, 3, 6, 10 mm/min from 0 up to 30 N of the maximum normal load. In consequence, COF, AE and crack density were observed to increase with increasing normal load or increasing scratching speed. Phase transformations from the silicon diamond structure to other structures were observed in the scratched grooves for the slow scratching speeds using micro-Raman spectroscopy.

Phase Transition of Single Crystal Silicon by Scratching Test (Scratching 시험에 의한 단결정 실리콘의 상전이)

  • 오한석;정성민;김현호;박성은;이홍림
    • Korean Journal of Crystallography
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    • v.12 no.2
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    • pp.102-112
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    • 2001
  • The mechanical properties of silicon crystals are important from the viewpoint of wafer and device fabrication processes. It is now widely recognized that silicon undergoes a series of phase transformations when subjected to high pressures, using conventional high pressure devices, such as diamond anvils or indenters. Diamond tip scratching on a silicon surface in the various conditions introduces various kinds of mechanical damage and stressed states. Micro Raman spectroscopy was used to observe the phase transition of single crystal silicon. As results, different morphologies were observed as functions of scratching speed and loading condition and various phases were observed as functions of scratching speed and loading condition.

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Rear drum brake creak(scratching) noise improvement during braking(or parking apply) (제동시 발생하는 리어 드럼브레이크 creak(scratching) 노이즈 개선)

  • Jang, Myunghoon;Park, Shin;Kim, Sunho;Kim, Sunghwan
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2013.04a
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    • pp.486-491
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    • 2013
  • Creak noise is kind of scratching noise which is usually generated in drum brake system on the vehicle. When driver brakes vehicle or applies parking lever, drum brake shoe moves to the drum side to stop the vehicle. And at that time, moving shoe scratches backing plate ledge surface, and that makes scratching noise in special condition. This study presents how we can generate creak noise in the laboratory and how we can reduce it by experimental approach. Through several and various type of tests, we could generate creak noise with damage on ledge area of the backing plate in the lab and we verified tab type shoe design can reduce this scratching noise. As a result of this study, we notified how creak noise happens in the vehicle, and that tab type design shoe has good performance of ledge area damage based on lab test(rig & dynamometer equipment), and that this can reduce potential risk of creak noise in the field.

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The Effects of Tribulus terrestris on Model of Allergic Rhinitis (백질여(白蒺藜)가 알레르기 비염 유발 동물 모델에 미치는 영향)

  • Chou, Ching-Yu;Kim, Yoon-Bum
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.24 no.2
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    • pp.28-34
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    • 2011
  • Background & Objectives : Allergic rhinitis is an inflammation or irritation of the mucous membranes that line the nose. Common symptoms include sneezing, a stuffy or runny nose, itchy eyes, nose and throat, and watery eyes. We aimed to determine therapeutic effects of Tribulus terrestris by observing changes of total IgE level and the scratching or rubbing around the nose behavior. Materials and Methods : Fifteen BALB/c mice were divided into three groups : AR group(allergic rhinitis elicitated), TT group(which ate herbal medicine) and AH group(which ate antihistamine). Allergic rhinitis was induced in the three groups by intraperitoneal and intranasal sensitization with 0.1% ovalbumin solution. Then Tribulus terrestris was orally administered only to the TT group of 28days, while the AH group was given antihistamine. We observed changes of total IgE level and the scratching or rubbing around the nose behavior. We used Kruskal-Wallis test statistically(p<0.05). Results : 1. Tribulus terrestris showed significantly decreased IgE level on the serum of the rat model. 2. Tribulus terrestris showed significantly decreased scratching or rubbing around the nose behaviors of the rat model. Conclusion : According to the above results, it is considered that Tribulus terrestris has an inhibitory effect on the process of allergic rhinitis and it can be used in relieving symptoms of allergic rhinitis.

Development of a New Probe to Realize Nano/Micro Mechanical Machining and In-Process Profile Measurement (나노인프로세스 형상계측 및 미세가공용 프로브의 개발)

  • Kweon, Hyun-Kyu;Choi, Seong-Dae
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.2 no.1
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    • pp.75-84
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    • 2003
  • In this paper, a new nano/micro-mechanical processing test machine was developed. This new test machine, which is based on the principle of the scanning force controlled probe microscope, can realize nano/micro-mechanical machining and in-process profile measurement. Experimental results of nano/micro indentation and scratching show that the controllable cutting depth of the test machine can be controlled by PZT actuator. Profile measurement of the machined surface has also been performed by using the test machine and a conventional AFM(Atomic Force Microscopy). A good agreement of the two measurement results have been achieved.

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Finite Element Analysis of Nano Deformation for Hyper-fine Pattern Fabrication by Application of Nano-scratch Process (나노스크래치 공정을 이용하여 극미세 패턴을 제작하기 위한 나노 변형의 유한요소해석)

  • 이정우;강충길;윤성원
    • Journal of the Korean Society for Precision Engineering
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    • v.21 no.3
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    • pp.139-146
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    • 2004
  • In this study, to achieve the optimal conditions for mechanical hyper-fine pattern fabrication process, deformation behavior of the materials during indentation scratch test was studied with numerical method by ABAQUS S/W. Brittle materials (Si, Pyrex glass 7740) were used as specimens, and forming conditions to reduce the elastic recovery and pile-up were proposed. The indenter was modeled as a rigid surface. Minimum mesh sizes of specimens are 1-l0nm. Variables of the nanoindentation scratch test analysis are scratching speed, scratching load, tip radius and tip geometry. The nano-indentation scratch tests were performed by using the Berkovich pyramidal diamond indenter. Comparison between the experimental data and numerical result demonstrated that the FEM approach can be a good model of the nanoindentation scratch test. The result of the investigation will be applied to the fabrication of the hyper-fine pattern.

Intra-articular Injection of $IL-1{\beta}$ Facilitated Formalin-induced Temporomandibular Joint Pain in Freely Moving Rats

  • Choi, Hyo-Soon;Jung, Sung-Chul;Choi, Byung-Ju;Ahn, Dong-Kuk
    • The Korean Journal of Physiology and Pharmacology
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    • v.9 no.1
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    • pp.23-27
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    • 2005
  • The present study was performed to investigate the effects of intra-articular injection of interleukin-1${\beta}$ (IL-1${\beta}$) on the formalin-induced temporomandibular joint (TMJ) pain. Under anesthesia, a 30-gauge needle was introduced into the right TMJ region for injection of formalin. Microinjection of 50 ${\mu}l$ of 5% formalin significantly produced noxious scratching behavioral response, and the scratching behavior lasted for 40 min. Although the responses produced by formalin injection were divided into two phases, the response of 1st phase did not significantly differ from the scratching behavior response in the saline-treated group. We examined the effects of intra-articular injection of IL-1${\beta}$ on the number of noxious behavioral responses produced by 50${\mu}l$ of 5% formalin injection. Intra-articular injection of 100 pg and 1 ng of IL-1${\beta}$ significantly increased the number of behavioral responses of the 2nd phase, while 10 pg of IL-1${\beta}$ did not change the formalin-induced behavioral responses. To investigate whether IL-1 receptor was involved in the intra-articular administration of IL-1${\beta}$-induced hyperalgesic response, IL-1 receptor antagonist (IL- ra, 50 ng) was administrated together with IL-1${\beta}$ injection. IL-1${\beta}$ receptor antagonist blocked IL-1${\beta}$- induced hyperalgesic response in the TMJ formalin test. These results suggest that intra-articular injection of IL-1${\beta}$ facilitated the transmission of nociceptive information in the TMJ area.