• Title/Summary/Keyword: resonance response

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Resonance Changes in the External Auditory Canal Associated with the Ear Canal Volume (외이도용적에 따른 외이도공명의 변화)

  • Choi, Ah-Hyun;Lee, Mi-So;Choi, Ah-Reum;Heo, Seung-Deok
    • Phonetics and Speech Sciences
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    • v.1 no.3
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    • pp.151-154
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    • 2009
  • The external ear generates resonance gain because of anatomical characteristics. The ear canal resonance is influenced by the length and volume of the ear canal, the pinna, the concha cavity, the body trunk, and the speed of sound wave. This study is focus on the influence of the volume of ear canal. 17-healthy-adult (32 ears) were participated. They did not have any medical and ear disease history. The maximum resonance frequency of the ear canal was 2675 (${\pm}265$) Hz at azimuth $0^{\circ}$ and 2784 (${\pm}268$) Hz at azimuth $45^{\circ}$. The resonance gain was 18.1 (${\pm}3.9$) dB at azimuth $0^{\circ}$ and 17.9 (${\pm}3.8$) dB at azimuth $45^{\circ}$, respectively. The ear canal volume was 0.78 (${\pm}0.2$) cc and 1.32 (${\pm}0.8$) cc including static compliance. The ear canal resonance was changed depending on the ear canal volume. It was also statistically correlated at azimuth $0^{\circ}$ (p=0.038) and $45^{\circ}$ (p=0.013), respectively. The resonance gain was not correlated with the ear canal volume. The change of resonance frequency according to the ear canal volume will be useful information in the field of audiological rehabilitation especially for hearing aids fitting. In addition, we expected this study can provide the basic information for the study of the external ear resonance characteristics.

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Analysis of Seismic Response of the Buried Pipeline with Pipe End Conditions (II) (단부 경계조건을 고려한 매설관의 동적응답 해석 (II))

  • Lee, Byong-Gil;Park, Byung-Ho;Jeong, Jin-Ho
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.328-337
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    • 2005
  • This work reports results of our study on the dynamic responses of the buried pipelines both along the axial and the transverse directions under various boundary end conditions. We have considered three cases, i.e., the free ends, the fixed ends, and the fixed-free ends for the axial direction, and three more cases including the guided ends, the simply supported ends, and the supported-guided ends for the transverse direction. In order to investigate the effect of the boundary end conditions for the dynamic responses of the buried pipeline, we have devised a computer program to find the solutions of the formulae on the dynamic responses (displacements, axial strains, and bending strains) under the various boundary end conditions considered in this study. The dynamic behavior of the buried pipelines for the forced vibration is found to exhibit two different forms, a transient response and a steady state response, depending on the time before and after the transfer of a seismic wave on the end of the buried pipeline. The former is identified by a slight change in its behavior before the sinusoidal-shaped seismic wave travels along the whole length of the pipeline whereas the latter by the complete form of a sinusoidal wave when the wave travels throughout the pipeline. The transient response becomes insignificant as the wave speed increases. We have observed a resonance when the mode wavelength matches the wavelength of the seismic wave, where the mode number(k) of resonance for the axial direction is found to be $\overline{\omega}/{\pi}V+1/2$ for the fixed-free ends, $\overline{\omega}/{\pi}V+1$ for the free ends, and $\overline{\omega}/{\pi}V$ for the fixed ends, respectively. By adding 10 more modes to the mode number(k) of resonance, we were able to study all the dynamic responses of the buried pipeline for the axial direction. On the other hand, we have not been able to observe a resonance in the analysis for the transverse direction, because the dynamic responses are found to vanish after the seventh mode. From the results of the dynamic responses at the many points of the pipeline, we have found that the responses appeared to be dependent critically on the boundary end conditions. Such effects are found to be most prominent especially for the maximum values of the displacement and the strain and its position.

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Brain Activation Evoked by Sensory Stimulation in Patients with Spinal Cord Injury : Functional Magnetic Resonance Imaging Correlations with Clinical Features

  • Lee, Jun Ki;Oh, Chang Hyun;Kim, Ji Yong;Park, Hyung-Chun;Yoon, Seung Hwan
    • Journal of Korean Neurosurgical Society
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    • v.58 no.3
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    • pp.242-247
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    • 2015
  • Objective : The purpose of this study is to determine whether the changes of contralateral sensorimotor cortical activation on functional magnetic resonance imaging (fMRI) can predict the neurological outcome among spinal cord injury (SCI) patients when the great toes are stimulated without notice. Methods : This study enrolled a total of 49 patients with SCI and investigated each patient's preoperative fMRI, postoperative fMRI, American Spinal Injury Association (ASIA) score, and neuropathic pain occurrence. Patients were classified into 3 groups according to the change of blood oxygenation level dependent (BOLD) response on perioperative fMRI during proprioceptive stimulation with repetitive passive toe movements : 1) patients with a response of contralateral sensorimotor cortical activation in fMRI were categorized; 2) patients with a response in other regions; and 3) patients with no response. Correlation between the result of fMRI and each parameter was analyzed. Results : In fMRI data, ASIA score was likely to show greater improvement in patients in group A compared to those belonging to group B or C (p<0.001). No statistical significance was observed between the result of fMRI and neuropathic pain (p=0.709). However, increase in neuropathic pain in response to the signal change of the ipsilateral frontal lobe on fMRI was statistically significant (p=0.030). Conclusion : When there was change of BOLD response at the contralateral sensorimotor cortex on perioperative fMRI after surgery, relief of neurological symptoms was highly likely for traumatic SCI patients. In addition, development of neuropathic pain was likely to occur when there was change of BOLD response at ipsilateral frontal lobe.

Determination of Tyrosinase mRNA in Melanoma by Reverse Transcription-PCR and Optical Mirror Resonance Biosensor

  • Taeboo Choe;Park, Inchul;Seokil Hong
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.7 no.4
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    • pp.212-215
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    • 2002
  • Tyrosinase transcript In the blood Is known as the marker of malignant melanoma and it has been often determined by using reverse transcription-polymerase chain reaction (RT-PCA) . However, after the PCR process, the quantification of amplified CDMA by the gel electrophoresis is not reliable and time-consuming. for this reason, we tried to quantify the PCR product using a cuvette-type biosensor, where the oligonucleotide probe was immobilized on the cuvette surface and the single strand CDMA, the denatured PCH product, was then hybridized onto the immobilized probe to give a response signal. The response was Immediate and takes 15 min to obtain a stable signal. The biosensor was much more sensitive comparing to the gel electrophoresis method. The quantification of PCR product using a cuvette-type biosensor was feasible and rapid.

Design of a Side Mirror for Passenger Vehicle Based on Vibration Characteristics (진동 특성을 고려한 승용차용 사이드 미러의 설계)

  • Son, Sang-Uk;Son, Kwon
    • Journal of KSNVE
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    • v.9 no.4
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    • pp.703-713
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    • 1999
  • A side mirror is an important safety tool with which the driver can observe objects out of sight. This paper presents an organized design technology for the side mirror of improved vibration characteristics. Resonance response to forced vibration is critical to observability through the mirror to be designed. This study aims at the reduction of vibration level by the modification of mirror structures and consequent effects are predicted by computer simulations. We used a three-dimensional solid modeling and the modal and frequency analysis ; Pro/Engineer is used as a solid modeler; Pro/Mechanica for vibration analysis. The simulation results are compared with those obtained in experiemnts to check the validity by the three-dimensional modeling. The design technique of side mirror has been established and found to be effective in vibration analysis of redesigned parts.

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Backbone Assignment of the N-terminal Domain of Human Replication Protein A 70 kDa

  • Lee, Sungjin;Park, Chin-Ju
    • Journal of the Korean Magnetic Resonance Society
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    • v.20 no.4
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    • pp.138-142
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    • 2016
  • Replication Protein A (RPA) is the eukaryotic single-stranded DNA binding protein. It involves in DNA replication, repair, and damage response. Among three subunits, RPA70 has a protein-protein binding domain (RPA70N) at the N-terminal. It has known that the domain recruits several damage response proteins to the damaged site. Also, it is suggested that there are more candidates that interact with RPA70N. Even though several studies performed on the structural aspects of RPA70N and its ligand binding, the backbone assignments of RPA70N is not available in public. In this study, we present the backbone assignments of RPA70N.

Modeling of the Structural Response of Pipes to Internal Blast Loading (관내 전파되는 파동에 대한 파이프의 구조적 반응에 대한 모델링)

  • Kim, Dae-Hyun;Yoh, Jai-Ick
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2008.05a
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    • pp.9-13
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    • 2008
  • The moving load such as a shock wave in a pipe propagates with a specific velocity. This internal load speed determines the level of flexural wave excitation and the possibility of resonant response leading to a large deformation. In this paper, we present particular solutions of displacements and the resonance conditions when the moving load is propagating in a pipe. These analytical results are compared to numerical simulations obtained using a hydrocode. We expect to identify potential explosion hazards in the general power industries.

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Dynamic Analysis for Performance Improvement of Line Center (라인센터의 성능향상을 위한 동특성 해석)

  • Cheong, Seon-Hwan;Choi, Seong-Dae;Kweon, Hyun-Kyu;Shon, Jae-Yool
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.2 no.2
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    • pp.75-83
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    • 2003
  • Recently, the machine tools have been needed for high speed and accuracy to increase productivity. The most Important thing to get a more stabilized machine is to know the frequency response which has an effect on manufacture a lot. This problem should be considered seriously by many researchers. There are many application programs about FEM but Just using FEM program to get information of the object is not enough to put our confidence in the stability of the machine tool design. Therefore, the purpose of this research is to make a study for proving one of the ways to design to produce stabilized a machine more efficiently by comparing FRT method and FEM. At these two tests, we can learn about the frequency response area causing resonance and we can reconfirm the result to trust.

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Acupuncture stimulation for motor cortex activities: Evidence from 3T functional MRI study

  • 최보영;전신수;유승식;최기순;박상동;임은철;정성택;이형구;서태석
    • Proceedings of the KSMRM Conference
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    • 2003.10a
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    • pp.85-85
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    • 2003
  • Purpose: To investigate whether or not acupuncture of GB34 produces a significant response of the modulation of somatomotor areas by functional magnetic resonance imaging (fMRI) study. Materials and methods: The acupoint, GB34, located in the back of the knee, is known to be effective in recovering motor function after stroke. Using 3T MRI scanner, functional MR imaging of the whole brain was peformed in 12 normal healthy subjects during two stimulation paradigms; acupuncture manipulation on GB34 and sham points. This study investigates the activation of the motor cortex elicited by a soft and an intensified stimulation of GB 34.Three different paradigms were carried out to detect any possible modulation of the Blood Oxygenation Level Dependent (BOLD) response in the somatomortor area to motor stimulation through acupuncture.

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A Study on Vibration Reduction of Local Structure of Medium-speed Diesel Engine (중속 디젤엔진 국부 구조물의 진동저감 연구)

  • Jung, Kun-Hwa;Lee, Jun-Ho;Son, Jung-Ho;Ryoo, Young-Seok
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2011.10a
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    • pp.257-261
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    • 2011
  • The failures of local structure of marine medium-speed diesel engine occurred in durability test. The vibration response of the whole engine was in an acceptance level, but the local structures were broken. ODS test and vibration measurement were carried out in order to investigate the root cause of durability problem. These tests revealed that the root cause of failures was excessive vibration by $4.5^{th}$ resonance between engine body and local structure. The best solution to reduce the vibration response is to change the type of mount. After a rigid mount was replaced by a flexible mount, maximum vibration level dropped to 72%.

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