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A method to estimate the absolute ultrasonic nonlinearity parameter from relative measurements
Kim, Jongbeom,Song, Dong-Gi,Jhang, Kyung-Young Elsevier BV 2017 Ultrasonics Vol.77 No.-
<P><B>Abstract</B></P> <P>The ultrasonic nonlinearity parameter ( β ) is determined from the particle displacement amplitudes of the fundamental and second-order harmonic components in an ultrasonic wave propagated through a material. This parameter is generally referred to as the absolute parameter. However, measuring the second harmonic component is especially difficult because its amplitude is usually much smaller than those of signals in typical ultrasonic measurements. For this reason, most studies use the relative parameter determined using the measured electric signal amplitudes of the fundamental and second harmonic ultrasonic waves. However, in many occasions, the absolute parameter is needed for a quantitative assessment of material degradation. This study proposes a method to estimate the absolute parameter from a measured relative parameter along with a proportionality constant between normalized absolute and relative parameters. This method is based on the observed fact that the ratio of between normalized relative and absolute parameters is identical after compensating proportionality constant. The method was experimentally validated for Al6061-T6 alloy specimens heat-treated for different aging times. The parameter determined through the proposed method were compared with the absolute parameters which were measured separately. The results show that these two parameters were close to each other within the measurement errors.</P>
초음파 파라미터를 이용한 사과의 기계적 특성 분석을 위한 기초 연구
이상대 ( Sang Dae Lee ),김기복 ( Ki Bok Kim ),박정길 ( Jeong Gil Park ),김만수 ( Man Soo Kim ) 전북대학교 농업과학기술연구소 2010 농업생명과학연구 Vol.41 No.1
This study was performed to develop the nondestructive evaluation technique for the mechanical properties of fruit using ultrasonic technique. Ultrasonic parameters such as sound velocity, peak amplitude, attenuation coefficient in maximum amplitude according to storage time were measured using the fabricated 100 kHz transmitting and receiving ultrasonic transducers. The mechanical properties such as rupture point and elastic modulus of apple were measured by universal testing machine. Multiple linear regression (MLR) models to estimate the mechanical properties of apple were developed using the ultrasonic parameters. The coefficients of determination of MLR models for rupture point and elastic modulus of apple were 0.5635 and 0.7089, respectively.
Yingshuai Xu,Fei Gao,Ping Zou,Qinjian Zhang,Fanglei Fan 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.9
When processing difficult-to-cut materials, conventional turning (CT) typically suffers from the problems of large cutting force, difficult chip removal, and serious tool wear, resulting in deteriorated processing quality, reduced processing efficiency, and increased processing costs. In addition, special-purpose machine tools used for ultrasonic machining exhibit disadvantages, such as narrow application scope, high manufacturing cost, and poor universality; thus, they are not conducive to being popular in actual production and processing. Accordingly, this study analyzed the characteristics of ultrasonic wave, the mechanism of ultrasonic vibration-assisted turning (UAT), and the formation of a machined surface in UAT. Moreover, the machining system of UAT was established. This system applied an ultrasonic wave vibration device to an engine lathe to meet the requirements of vibration cutting in actual production. Simultaneously, Inconel 718, a typical and widely used difficult-to-cut material, was selected for the experimental study. The machining effect of UAT was analyzed in detail, including surface roughness, surface topography, and chip shape. Results indicated that ultrasonic amplitude, cutting speed, depth of cut, and feed rate exert considerable influences on the machining effect. UAT can achieve this effect, which is difficult to realize via CT, under the condition of a reasonable selection of technological parameters. This research can provide theoretical support and experimental basis for the development and practical application of UAT.
Seok Chang-Sung,Kim Jeong-Pyo The Korean Society of Mechanical Engineers 2005 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.19 No.2
Mechanical properties of in-service facilities are required to evaluate the integrity of power plants and chemical plants. Non-destructive technique can be used to evaluate the mechanical properties. To investigate the mechanical properties using ultrasonic technique, the four classes of thermally aged specimens were prepared using an artificially accelerated aging method. Ultrasonic tests, tensile tests, fracture toughness tests, and hardness tests were performed for the specimens. Then the mechanical properties were compared with ultrasonic parameters such as attenuation and non-linear parameter. From the investigation, we confirm that the ultrasonic parameter can be used to evaluate the mechanical properties.
Application of Nonlinear Ultrasonic Method for Monitoring of Stress State in Concrete
Kim, Gyu Jin,Park, Sun Jong,Kwak, Hyo Gyoung The Korean Society for Nondestructive Testing 2016 한국비파괴검사학회지 Vol.36 No.2
As the lifespan of concrete structures increases, their load carrying capacity decreases owing to cyclic loads and long-term effects such as creep and shrinkage. For these reasons, there is a necessity for stress state monitoring of concrete members. Particularly, it is necessary to evaluate the concrete structures for behavioral changes by using a technique that can overcome the measuring limitations of usual ultrasonic nondestructive evaluation methods. This paper proposes the use of a nonlinear ultrasonic method, namely, nonlinear resonant ultrasonic spectroscopy (NRUS) for the measurement of nonlinearity parameters for stress monitoring. An experiment compared the use of NRUS method and a linear ultrasonic method, namely, ultrasonic pulse velocity (UPV) to study the effects of continuously increasing loads and cyclic loads on the nonlinearity parameter. Both NRUS and UPV methods found a similar direct relationship between load level and that parameter. The NRUS method showed a higher sensitivity to micro-structural changes of concrete than UPV method. Thus, the experiment confirms the possibility of using the nonlinear ultrasonic method for stress state monitoring of concrete members.
Application of Nonlinear Ultrasonic Method for Monitoring of Stress State in Concrete
김규진,박선종,곽효경 한국비파괴검사학회 2016 한국비파괴검사학회지 Vol.36 No.2
As the lifespan of concrete structures increases, their load carrying capacity decreases owing to cyclic loads and long-term effects such as creep and shrinkage. For these reasons, there is a necessity for stress state monitoring of concrete members. Particularly, it is necessary to evaluate the concrete structures for behavioral changes by using a technique that can overcome the measuring limitations of usual ultrasonic nondestructive evaluation methods. This paper proposes the use of a nonlinear ultrasonic method, namely, nonlinear resonant ultrasonic spectroscopy (NRUS) for the measurement of nonlinearity parameters for stress monitoring. An experiment compared the use of NRUS method and a linear ultrasonic method, namely, ultrasonic pulse velocity (UPV) to study the effects of continuously increasing loads and cyclic loads on the nonlinearity parameter. Both NRUS and UPV methods found a similar direct relationship between load level and that parameter. The NRUS method showed a higher sensitivity to micro-structural changes of concrete than UPV method. Thus, the experiment confirms the possibility of using the nonlinear ultrasonic method for stress state monitoring of concrete members.
Application of Nonlinear Ultrasonic Method for Monitoring of Stress State in Concrete
Gyu Jin Kim,Sun Jong Park,Hyo Gyoung Kwak 한국비파괴검사학회 2016 한국비파괴검사학회지 Vol.36 No.2
As the lifespan of concrete structures increases, their load carrying capacity decreases owing to cyclic loads and long-term effects such as creep and shrinkage. For these reasons, there is a necessity for stress state monitoring of concrete members. Particularly, it is necessary to evaluate the concrete structures for behavioral changes by using a technique that can overcome the measuring limitations of usual ultrasonic nondestructive evaluation methods. This paper proposes the use of a nonlinear ultrasonic method, namely, nonlinear resonant ultrasonic spectroscopy (NRUS) for the measurement of nonlinearity parameters for stress monitoring. An experiment compared the use of NRUS method and a linear ultrasonic method, namely, ultrasonic pulse velocity (UPV) to study the effects of continuously increasing loads and cyclic loads on the nonlinearity parameter. Both NRUS and UPV methods found a similar direct relationship between load level and that parameter. The NRUS method showed a higher sensitivity to micro-structural changes of concrete than UPV method. Thus, the experiment confirms the possibility of using the nonlinear ultrasonic method for stress state monitoring of concrete members.
Sol-Hui Song,Hoon Kim 한국피부과학연구원 2021 아시안뷰티화장품학술지 Vol.19 No.4
목적: 본 연구에서는 안티에이징의 대중화에 따른 미용 시술 시 사용되는 마취제품을 보다 효과적으로 사용하기 위해 연구하였다. Lidocaine을 함유한 hydrogel을 초음파로 미용시술 시에 사용한다면 통증완화에 보다 효과적일 것으로 판단되어 hydrogel을 제조하 였다. 방법: 제조한 하이드로겔과 시판 중인 겔을 비교하여 초음파 치료에 사용할 수 있는지 평가하였으며, 초음파 적용가능성에 따 라 피부를 통한 침투와 초음파 한도에 따른 피부 침투에 미치는 영향을 평가하였다. 초음파 처리 시 사용성 및 최적의 초음파 매개 변수를 알아보았다. 결과: 제조한 하이드로겔의 점도측정, 겔화율, 팽윤도, 피부투과실험, HPLC 분석한 결과 모두 적합한 특성을 보였으며, 주파수 1MHz, 순환주기 Low 200, High 50 일 때가 가장 피부투과율이 높아지는 초음파 조건임을 확인 할 수 있었다. 결 론: 결론적으로 Lidocaine을 함유한 hydrogel은 초음파 치료 시 피부투과율을 높여 더 빠르게 목표하는 양을 경피에 투과시킬 수 있 으며 이는 초음파의 매개변수에 따라서 더 효과적으로 투과시킬 수 있었다. 이에 미용 시술에 사용 시 적용이 가능한 것으로 판단된다. Purpose: In this study, we study to more effectively use anesthesia products used in beauty procedures following the popularization of anti-aging. Hydrogel, which contains lidocaine, is believed to be more effective in relieving pain if used in cosmetic procedures with ultrasonic waves. Methods: The availability of manufactured hydrogels and commercial gels for ultrasonic treatment was compared, and the effect on skin penetration and skin penetration due to ultrasonic limitations was evaluated based on their applicability. Usability and optimal ultrasound parameters were identified during ultrasound treatment. Results: Viscosity measurement, gelation rate, swelling, skin permeability experiment, and HPLC analysis of manufactured hydrogels all revealed properties, with skin permeability being highest at frequency 1 MHz, cycle low 200, and high 50. Conclusions: Finally, hydrogels containing lidocaine increased skin permeability during ultrasound treatment, allowing for faster targeted transdermal transmission that was more effective depending on the ultrasound parameters. As a result, it is determined that it can be used in cosmetic procedures.
Radhia Trabelsi,Moncef Bouanz,Adel Toumi 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.8
We measured the ultrasonic velocity, U, density, , and viscosity, in Isobutyric acid - water binary liquid mixtures over the entire composition range at temperatures ranging from 300.15 to 313.15 K under atmospheric pressure. The experimental data values were analyzed to determine, various acoustical parameters: adiabatic compressibility, , acoustic impedance, Z, free length, Lf, free volume, Vf, molar volume, Vm, relaxation time, , absorption coefficient, /f2, internal pressure, i, Gibb’s free energy, G, cohesive energy, CE, Wada’s constant, W, Rao’s constant, Rm and relative association, RA. The variation of these parameters versus the mixture composition was explained on the basis of the intermolecular interactions between the components of the mixture.
Characteristics of Ultrasonic Nonlinearity by Thermal Fatigue
Weibin Li,조윤호,현승호 한국정밀공학회 2012 International Journal of Precision Engineering and Vol. No.
The deterioration conditions of nuclear power plants and chemical plants have raised deep concerns about the safety of high-risk structures. The safety of a structure can be secured by evaluations of breakages and lifespan in the early stage. Therefore, the material condition of a structure needs to be estimated. A nonlinear ultrasonic evaluation method is reportedly more sensitive on microscopic changes of a material than a linear evaluation method. Therefore, the nonlinear ultrasonic technique based on ultrasonic nonlinearity is considered a promising method of evaluation for breakages and lifespan. This study measured the changes in nonlinear parameters by using a nonlinear ultrasonic method, observed the microstructure of a heated material, and analyzed the relation between the size of the microstructure and the changes in the nonlinear parameters.