PRIMARY RESONANCE ANALYSIS OF MIDDLE EAR SYSTEM SUBJECTED TO NARROW-BAND RANDOM EXCITATION

“…Taking the middle ear system as the research object,the nonlinear vibration characteristics of the human ear under narrow-band random acoustic excitation were studied.According to the three-degree-of-freedom nonlinear model of the middle ear,the nonlinear random vibration equation was established and the regular matrix was introduced to obtain the nonlinear vibration equation in the regular coordinate.The amplitude-frequency characteristic equation of the first-order primary resonance of the middle ear system was obtained by the multi-scale method.Through the bifurcation diagram and the maximum Lyapunov index,it was found that the middle ear system produces different motions under different excitations.The Ito stochastic dif⁃ferential equation of the middle ear system was derived,the approximate expression of the second-order moment of the system was obtained by using the rectangular method,and the influence of the random disturbance intensity on the middle ear system was verified.The results show that the resonance area of the system increases with the increase of the external excitation.When the random disturbance intensity increases,the thickness of the limit cycle of the phase diagram becomes thicker.…”
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A Dual-Band Printed End-Fire Antenna with DSPSL Feeding by Daofeng Ye, Yuanxin Li, Zhixi Liang, Yunliang Long

“…The measured bandwidths were 18.3% for the lower frequency band (2.28–2.74 GHz) and 12.6% for the upper frequency band (5.46–6.2 GHz).…”
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新型机加工弹簧静压状态下的应力集中研究 by 王立超, 周燕飞

“…The stress concentration at the end of spiral groove is very serious during the static tension and compression of the new machined spring,which has a great influence on the strength and fatigue life of the spring.The influence of spring basic parameters on the stress concentration coefficient was analyzed by ANSYS software,and the theoretical criterion for the existence of stress concentration in machined springs is determined.The effects of tangential stress release hole on compression deformation and stress concentration coefficient were investigated; Based on the strength theory and bending theory of curved beam,the formula of maximum equivalent stress without stress concentration was deduced.The results show that when the ratio of the width of the spiral groove to the pitch is less than 0.5,stress concentration occurs in machined springs with the middle diameter between 15 mm ～ 35 mm.The stress concentration can be basically eliminated by cutting stress release hole at the end of spiral groove and controlling its size to be close to the height of rectangular section.The error between the equivalent stress value of the inner ring and the simulation value is less than 3%.It provides an important reference for the subsequent engineering design and application of the new spring.…”
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Computer modelling of coupled spaces: variations of eigenmodes frequency due to a change in coupling area by Mirosław MEISSNER

“…In this investigation, an eigenvalue problem was solved numerically for a simple room system consisting of two connected rectangular spaces. In a numerical procedure, the forced oscillator method with a finite difference algorithm was applied. …”
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Cholesterolosis Bulbi in an Eye with Retinal Capillary Hemangioma: A Rare Association with Chemical Analysis by Abdelwahab Aleshawi, Rami Al-Dwairi, Mohammad Al Qudah, Abdallah Sharayah, Mahmood Al Nuaimi, Hashem Abu Serhan

“…Anterior chamber and vitreous washout and endo-laser photocoagulation for the hemangioma were performed. Analysis of the aqueous sample revealed numerous well-demarcated, rectangular, or polygonal lipid-like crystals on light microscopy. …”
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Color stability of CAD/CAM provisional materials after immersion in different coloring solutions: a comparative study by Selver Suna Başak, Zeynep Şen Yilmaz, Funda Bayındır

“…One hundred and twenty rectangular specimens of 2 mm thickness for each provisional material were fabricated. …”
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Experimental and Numerical Study of Stratified Sloshing in a Tank under Horizontal Excitation by Maojun Luo, Mi-An Xue, Xiaoli Yuan, Feng Zhang, Zhi Xu

“…The numerical results of dynamic pressure were validated against the experimental data, showing that the employed model can accurately simulate the stratified liquids sloshing phenomenon. …”
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Nonlinear Analysis and Optimization of Recycled Aggregate Concrete Cross-Sections Based on Restoring Force Models by Chaolong Qi, Changqing Wang, Zhiming Ma

“…The findings reveal that a reduction in the axial compression ratio from 0.60 to 0.57 results in a 15% increase in ductility, while a higher reinforcement ratio leads to a 20% enhancement. In addition, rectangular sections were found to be more sensitive to variations in material strength than square sections, offering key insights for structural optimization. …”
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A facile route for controlled alignment of carbon nanotube-reinforced, electrospun nanofibers using slotted collector plates by G. R. Rakesh, G. S. Ranjit, K. K. Karthikeyan, P. Radhakrishnan, P. Biji

“…Among various collector geometries, rectangular slotted collectors with circular ends showed good fiber alignment over a large collecting area. …”
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Unsteady RANS and LES Simulation of an Ideal Rankine Vortex Decay by Md. Shahjahan Ali, Takashi Hosoda, Ichiro Kimura

“…The governing equations for mean velocities and turbulent flows were discretized with the finite volume method based on a staggered grid system. …”
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Optimal geometrical selection of skin mesh: experimental analysis and numerical optimization by Mehdi Khayami, Aisa Rassoli, Alireza Feizkhah

“…Hyperelastic properties of healthy and meshed skin were obtained through uniaxial tensile tests, and different geometries were analyzed using Abaqus. …”
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Mathematical Modeling of the Effect of Temperature on the Dynamic Characteristics of a Cantilever Beam with Flexible Root by Samaher Mohammed Sarhan, Salah Al-Zubaidi

“…The chosen linear spring coefficients were 0.01, 0.1, 100, and ∞ N/m while rotational spring coefficients were 0.01, 0.1, 100, and ∞ N·m/rad. …”
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Axial Compression Test and Bearing Capacity Analysis of Biaxial Prestressed Angle Steel Plate Fully Wrapped Reinforced Concrete Short Column by Zhenhua Ren, Xiantao Zeng, Yaqian Shen, Huanlin Huang

“…A new external reinforcement method is proposed in this research by using the prestressed angle steel plate to fully wrap a reinforced concrete column with a rectangular cross section. To study the axial compression characteristics of the new proposed structure, twenty pieces of the concrete columns were built using the normal reinforcement: five control columns and fifteen reinforced concrete columns, with three groups of different prestressed angle steel plates. …”
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The Existence of Undergrowth at Forest Garden Stands in Grand Forest Park, Lampung Province by Indriyanto Indriyanto, Nurani Hardikananda Indriyanto

“…Data were analyzed by calculating density, frequency, important value index, and Shannon diversity index. …”
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Numerical Investigation of Multiphase Transport Model for Hot-Air Drying of Food by Burak Turkan, Ahmet Serhan Canbolat, Akin Burak Etemoglu

“…In this study, air velocities of 0.5, 0.8 and 1 m s-1, air temperatures of 40, 50 and 60 °C and the geometric forms of rectangular, cylindrical and square were selected for hot air drying process. …”
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Effects of Low- and High-Frequency Side Bands of Notched Noise on Masking and Auditory Filter Shape at Very High Frequencies by Monika KORDUS, Borys KOWALEWSKI

“…Unlike in the classical experiments conducted with the use of Patterson method the levels as well as power spectrum densities of the lower and upper component bands of the notched noise masker were not the same and were set such as to produce the same amount of masking at the 10-kHz frequency. …”
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Fortificaţia de la Ungra. Cercetări magnetometrice recente by Alexandru Popa, Silviu Gridan, Andrea Popa

“…As a main conclusion, traces of a rectangular fortification with external dimensions of about 105×125 m were identified. …”
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Biomechanical Evaluation of Attachment and Trimline Modifications in Maxillary Molar Distalization Using Clear Aligners by Tulca Büyükpatır Türk, Ebru Küçükkaraca

“…Overall, extended trimlines were associated with increased total distalization and improved force transmission. …”
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Numerical Determination Of Cooling Performance On Heat Sink Using Impingement Jet by Rami Abdulraheem Abdulrezzaq Al-anı, Altuğ Karabey

“…These results were simulated numerically by using the ANSYS Fluent software. …”
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Incipient motion of tire rubber grains bed by Bruno Souza Costa Campello, Jorge Luis Zegarra Tarqui, Carlos Barreira Martinez, Aloysio Portugal Maia Saliba, Edna Maria de Faria Viana

“…The experimental critical values of the Shields parameter of the rubber particles were satisfactory because the values were within the dispersion range of the experiments by Shields diagram.…”
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