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Vascular Cognitive Impairment (VCI) is a cognitive disorder associated with cerebrovascular disorders. The cognitive regions included memory, attention, spatial-visual ability, and language. VCI became a significant challenge in the health sector worldwide. VCI problems commonly occurred in developed countries and started to emerge in developing countries. In 2013, there were 1 million VCI sufferers in Indonesia, and it is expected to double by 2030. Common causes of VCI are blood vessel disorders such as stroke, diabetes, brain injury, and high blood pressure. Neuro-feedback (NF) therapy can improve the quality of EEG of VCI patients. This study used quantitative (qEEG) parameters to differentiate between normal and VCI subjects as well as to quantify the EEG signal improvements before and after NF therapy by sound waves. The quantitative parameters used in this study included power parameters, wave duration, and percentage of each frequency band of EEG signals. EEG signals were collected from 25 normal subjects and 12 subjects diagnosed with VCI. Results showed the difference in absolute power and relative power between normal and VCI subjects. Normal subjects’ dominant frequency was in alpha band with average percentage of 50.4% while for VCI subjects dominant frequency was in delta band with an average percentage of73%. After each NF therapy session of VCI subjects by sound wave, there was an increase of alpha-band frequency by an average of 1.2%. In addition, decay occurs in delta band frequency by an average of 3.1%. There was no significant change in the wave duration during therapy. In conclusion, qEEG parameters can be used to differentiate between normal and VCI subjects, especially the EEG power parameters.

When designing premises that require good acoustics, their purpose needs to be known. It determines preparation of the acoustical project which includes acoustics related to sound wave propagation in a given area. For instance, in case of designing large concert halls, theatre or cinema halls, so-called modeling studies with using a numerical analysis might be of help in solving issues related to architectural acoustics. They allow to determine both what the most favourable shape of the interior is and which of its surfaces should absorb, reflect, disperse the sound or direct it in another place. We use specialized software to make good acoustic adaptations, which greatly facilitates us making decisions in the design phase.

Conceptual understanding is one of the most important aspects in the study of Physics because of it useful to understand principles behind certain phenomenon which happened. An innovative method was needed to strengthen and enhance student’s conceptual understanding, especially regarding the abstract subject such as magnetic field. For this reason, worksheet and exploration sheet based on PDEODE*E (Predict, Discuss, Explain, Observe, Discuss, Explore, and Explain) that uses Gauss Meter application as the smartphone technology has been designed to answer the problem. The magnetic field strength in different mediums is the physics subject which covered in this research. The research was conducted with the aim to know how effective smartphone technology-based PDEODE*E could be implemented as a physics learning strategy. The result of this research shows that students could show improvements in conceptual understanding that shown by the conclusion that was constructed during the learning process. Based on this result, PDEODE*E could become a solution to strengthen students’ conceptual understanding regarding physics subject, especially those that requires abstract thinking. This result also has shown that the application ofsmartphone technology could be used to support physics learning processes in the classroom, such as Gauss Meter in this research which used to measure the magnetic field, Light Meter which could be used in the concept of light, and Harmonicity Meter for the context of the sound wave.

Human cochlear is undeniably one of the most amazing organs in human body. The functional mechanism is very unique in terms of its ability to convert the sound waves in the form of mechanical vibrations into the electrical nerve impulses. It is known that the normal human auditory system can perceive the audible frequency range between 20 Hz to 20 kHz. Scientists have conducted several researches trying to build the artificial basilar membrane in the human cochlea (cochlear biomodel). Micro-electromechanical system (MEMS) is one of the potential inventions that have the ability to mimic the active behavior of the basilar membrane. In this paper, an array of MEMS bridge beams that are mechanically sensitive to the perceived audible frequency has been proposed. An array of bridge bridge beams with 0.5 µm thickness and length varying from 200 µm to 2000 µm have been designed operate within the audible frequency range. In the bridge beams design, aluminium (Al), copper (Cu), tantalum (Ta) and platinum (Pt) ha...

Dynamics of waves generated by scopes in gas centrifuges (GC) for isotope separation is considered. The centrifugal acceleration in the GC reaches values of the order of $10^6$g. The centrifugal and Coriolis forces modify essentially the conventional sound waves. Three families of the waves with different polarisation and dispersion exist in these conditions. Dynamics of the flow in the model GC Iguasu is investigated numerically. Comparison of the results of the numerical modelling of the wave dynamics with the analytical predictions is performed. New phenomena of the resonances in the GC is found. The resonances occur for the waves polarized along the rotational axis having the smallest dumping due to the viscosity., Comment: 4 pages, 2 figures, Proceedings of ICNAAM-2014

A few basic benchmark problems provided open to validate a proposed method are computed as a preliminary feasibility study of the molecular kinetic theory approach to aero-acoustic problems. Reasonable results were obtained.

In this paper, the coupled‐modes method of acoustic propagation is extended to waveguides with smoothly varying fluid‐elastic interfaces. To formulate the problem without recourse to the SH wave component from the ground up, we employ the {uz,uv}‐formulation developed in seismology. The result is remarkably different from that for fluid‐fluid interfaces; the boundary conditions imposed at fluid‐elastic interfaces give rise to terms including unknown boundary values so that the differential system obtained is not closed. To make the system closed, additional compatibility and constraining conditions have to be imposed.

Although an important effort has been devoted in the last decades to measure reaction cross sections of interest in astrophysics, most nuclear astrophysics applications still require the use of theoretical predictions to estimate experimentally unknown rates. The nuclear ingredients to the reaction model should preferably be estimated from microscopic or semi‐microscopic global predictions based on sound and reliable nuclear models which, in turn, can compete with more phenomenological highly‐parametrized models in the reproduction of experimental data. The latest developments made in deriving the nuclear inputs of relevance in astrophysics applications are reviewed. They mainly concern nuclear structure properties, nuclear level densities, optical potentials.New developments to improve the predictions of radiative neutron capture rates are also discussed. They include the recent improvements made to the TALYS reaction code and the analysis of the pre‐equilibrium contribution. The direct reaction mechanis...

A historical overview of some of the early theoretical and experimental work on dust acoustic waves is given. The basic physics of the dust acoustic wave and some of the theoretical refinements that have been made, including the effects of collisions, plasma absorption, dust charge fluctuations, particle drifts and strong coupling effects are discussed. Some recent experimental findings and outstanding problems are also presented.

For very high frequency ultrasound the Navier‐Stokes equations are inadequate. The Navier‐Stokes equations are first order in the mean free path in a gas. In this paper some sets of equations of second order are introduced and the nonlinear evolution of a sound wave is studied for one of these.

The nonlinear evolution of dust acoustic wave in magnetized dusty plasmas is shown to obey the Davey‐Stewartson I equation, which admits the so called dromion solutions.

In a series of large‐scale (N>100) studies of analogy use in college physics, we have explored how, when, and why analogies affect student reasoning. In the first of these studies, we demonstrated that analogies affect student reasoning when taught in a large enrollment physics course. In the present follow‐up study, we demonstrate that teaching EM waves concepts implicitly via analogy leads to greater conceptual change compared to teaching explicitly without analogies. Students were divided into two groups, one taught using analogies (string and sound waves) and the other taught without analogies (EM waves only). On a targeted concept question given before and after instruction, students who were taught with analogies outperformed those taught without analogies demonstrating that analogies can affect student reasoning in productive ways, even when taught implicitly. We propose framing as a mechanism to begin to explain why analogies can be productive when used implicitly.

The update of the Default POD curves for the detection of hard‐alpha inclusions in titanium alloy billet, is summarized. Included is a discussion of the data available, the analysis techniques used, and the results obtained. The results show that the Multizone technique is clearly superior to the conventional‐inspection technique and the estimated POD is significantly different from previous estimates, particularly for the conventional‐inspection technique. Although the final results obtained are specific to the hard‐alpha detection process, a number of the analysis issues encountered have generic interest. Included are the challenges associated with the estimation of POD from finds information (i.e. without full knowledge of misses), the assessment of POD when accept/reject decisions are based on multiple criteria, and treating situations in which a single regression line does not fit plots of log â versus log a.

Sonic IR imaging, which combines infrared imaging and ultrasound excitation, as a relative new member of the NDE family, has been drawing wider and wider attention due to its fast, wide area inspection capability. In our previous presentations and publications, we have described the application of acoustic chaos to Sonic IR imaging and have provided experimental illustrations as well. In addition, we have described realistic finite‐element models that simulate the heating of cracks in metals by both chaotic and non‐chaotic sound. These models allow for both friction and plastic deformation as sources of heating. In this paper, we present our further study on the physical mechanisms that are responsible for the advantages of chaotic sound for Sonic IR crack detection. Using finite‐element analysis, here we will present theoretical explanations, both for the origin of the chaos, and for the mechanisms responsible for the chaotic enhancement of crack detection.

Important effort has been devoted in the last decades to measure reaction cross sections. Despite such effort, many nuclear applications still require the use of theoretical predictions to estimate experimentally unknown cross sections. Most of the nuclear ingredients in the calculations of reaction cross sections need to be extrapolated in an energy or/and mass domain out of reach of laboratory simulations. In addition, some applications often involve a large number of unstable nuclei, so that only global approaches can be used. For these reasons, when the nuclear ingredients to the reaction models cannot be determined from experimental data, it is highly recommended to consider preferentially microscopic or semi-microscopic global predictions based on sound and reliable nuclear models which, in turn, can compete with more phenomenological highly-parametrized models in the reproduction of experimental data. The latest developments and improvements made in the prediction of nuclear structure properties and nuclear level densities within global microscopic models are reviewed.

The possibility to predict flow acoustic coupling at a sharp edge of an area expansion in a flow duct is explored, starting from the analytical model proposed by Nilsson and Boij. In the model, the ...

It has been previously shown experimentally that the use of chaotic sound, instead of a pure frequency, greatly enhances the heating, and hence the detectability of cracks using sonic infrared imaging (SIR). In this paper we show an example of the enhancement of crack heating through the use of chaotic sound. We also present the results of a finite element calculation, in which chaotic sound occurs spontaneously. This modeling confirms the experimental result that chaotic sound is more efficient than non‐chaotic sound excitation for heating the cracks.

For nonlinear acoustics for ultrahigh frequencies it is necessary to go beyond the Navier‐Stokes equations. For a gas the next set of equations due to Burnett were shown by Bobylev to have an unphysical instability. The Burnett equations are here stabilized as a set of equations for the fluid dynamic variables ρ, v, T, first in an approximation adequate for third order nonlinear acoustics and then in the general case.

A numerical approach was developed to model the propagation of shear and longitudinal sound waves in arbitrary, dense dispersions of spherical particles. Multiple scattering was simulated by modeling the fields with vector spherical wave functions, translating the scattered wave fields from one particle to another using translational addition theorems, and recomputing the scattering in an iterative manner. Realistic spectra and wave field images were produced for both ordered and fully random 3D material microstructures.

The usual description of dust‐modified ion‐acoustic and dust‐acoustic solitons in plasmas containing negative dust is in terms of Boltzmann distributions for the hotter species. In the dust‐modified ion‐acoustic regime, besides positive potential solitons, negative ones can also be generated, for non‐Boltzmann as well as for Boltzmann electrons, subject to very mild conditions that were previously ignored or given for weakly nonlinear solutions only. In the dust‐acoustic domain in plasmas with negatively charged dust, however, only negative potential solitons can occur, even when the lighter species have non‐Boltzmann distributions.

The corrosion of aeronautics structures in aluminum is difficult to detect at an early stage. Lamb waves are sometimes very sensitive to this damage and can be considered as good candidates for its detection. Unfortunately, the complex time evolution of Lamb wave signals makes difficult both utilization and interpretation of their interaction with defects. This paper demonstrates that, for many reasons, the analysis based on wavelets transform is of great help for recognition of Lamb modes and allows the cartography of corroded areas.

The status of collective processes in dusty is summarized. The effects of dust-neutral and dust-dust interactions, dust charge fluctuations, and magnetic fields on low-frequency electrostatic wave spectra are discussed. Some powerful mechanisms for exciting dusty plasma waves are presented. The importance of dust-acoustic wave induced wake-potential for charged dust attraction is illustrated. The relevance of our investigation to laboratory plasmas has been pointed out.

This paper presents the analysis (mathematical modeling) for the reduction of flexural wave (structure‐borne) noise that is generated by a line force on a steel plate. The steel plate is covered with a baffle (elastomer layer) to reduce the flexural wave noise. The main objective is to evaluate the performance of a velocity sensor located at the outer surface of the baffle layer. Toward this objective, the transmissibility of the plate displacement (velocity) through the baffle structure has been evaluated.

It’s shown that the second viscosity can become negative in the wide class of nonequilibrium media. Such media are acoustically unstable. The nonlinear waves evolution was investigated in the media with the negative second viscosity.

The photoacoustic microsope is shown to be an effective tool for the study of lower rank coals. (AIP)

We provide a new theory for visualizing the rf traveling acoustic wavefront in real time, with which we have not only obtained a steady visible image of the rf acoustic traveling wavefront—a moving phase object—but have also got rid of some confused concepts of the stroboscopic method.

The spin orientation type phase transition in SmCrO3 at T?34°K has been studied by means of bulk magnetization, sound wave propagation and specific heat measurements. The high and low temperature phases belong to Γ4(Cr:GxFz) and Γ2(Cr:GzFx) respectively. We find a reorientation region of ∠1°K with the beginning and the end points corresponding to second order phase transitions. Though common in the orthoferrites, this is the first clear evidence of a continuous spin reorientation in a RCrO3 compound. The continuous nature of the reorientation process is evident from peaks in the a and c axis susceptibilities and the softening of the elastic constant C55 at both ends of the transition region due to a resonant magnetoelastic coupling. From the anomaly in the specific heat, the entropy associated with the spin reorientation is found to be ΔE/R=0.21±0.01°K.