浅谈电梯运行中产生风音的原因及对策

声音在人们的日常生活中无处不在,如果长时间处于无规律嘈杂的声音环境中,不仅会使人产生不愉悦的情绪,严重的还可能危害到人们的身心健康。作为高层建筑物中最重要的运输设备,电梯工作时产生的噪音值大小会直接影响到乘客的乘坐体验,为了提高乘客的乘坐舒适度,降低电梯工作时产生的噪音值是非常必要的。电梯运行时产生噪音的声源有很多,主要的声源有驱动电梯上下运行的曳引机工作时发出的声音,电梯轿厢、轿门、轿架等部品振动产生的声音,电梯在开关门及系合时产生的声音,以及电梯高速运行时产生的风音等。本文主要针对电梯高速运行时产生风音的原因及常用的一些对策进行浅显的说明。

《风雅翼》叶音今音韵系及其与《中原音韵》的比较

对《风雅翼》447首古诗495个韵段分析考察,得出刘履叶音今音韵系二十一个韵部。它与《中原音韵》同中有异,显示出不同的语音层次。

The Equilibrium Range of Wind Wave Spectra: an Explanation Based on White Noise

Laboratory experiments and field observations show that the equilibrium range of wind wave spectra presents a – 4 power law when it is scaled properly. This feature has been attributed to energy balance in spectral space by many researchers. In this paper we point out that white noise on an oscillation system can also lead to a similar inverse power law in the corresponding displacement spectrum, implying that the – 4 power law for the equilibrium range of wind wave spectra may probably only reflect the randomicity of the wind waves rather than any other dynamical processes in physical space. This explanation may shed light on the mechanism of other physical processes with spectra also showing an inverse power law, such as isotropic turbulence, internal waves, etc.

Design of a continuously variable Mach-number nozzle

A design method was developed to specify the profile of the continuously variable Mach-number nozzle for the supersonic wind tunnel. The controllable contour design technique was applied to obtaining the original nozzle profile, while other Machnumbers were derived from the transformation of the original profile. A design scheme, covering a Mach-number range of3.0<Ma<4.0, was shown to illustrate the present design technique. To fully validate the present design method, computational fluid dynamics(CFD) analyses were carried out to study the flow quality in the test area of the nozzle. The computed results indicate that exit uniform flow is obtained with 1.19% of the maximal Mach-number deviation at the nozzle exit. The present design method achieves the continuously variable Mach-number flow during a wind tunnel running.

The Study and Practice of Theory and Composition Among Women in Ghana

The performance and composition of traditional choral music were championed and dominated by women. Unfortunately, the involvement of women in the practice of art music, specifically theory and composition in Ghana has been observed to be absent or very minimal, the cause of which is problematic to identify. This paper examines why women have been passive in the performance and composition of this musical genre, and suggests avenues for improvement in the situation. Fifteen women across various musical genres： Traditional, Art and Popular were interviewed to ascertain this fact. The results will serve as an aid for an improvement of this unfortunate situation in Ghana.

Analysis of Debussy Piano Music ＂fireworks＂ Performance

Debussy is one of the famous composers in music history, and he not only created a lot of innovative music, but also created a musical impressionist era, it is a landmark composers having. ＂Fireworks＂ is one of the important works of Debussy, which was the last song he composed 24 piano preludes, and this work fully reflects all his creative ideas, creative approach and creative style, as well as their patriotism inner world monologue. This paper focuses on the piano Debussy＇ s 24 Preludes a brief introduction, analyze the reasons for the formation of its style and structure of the work through, music image, sound system and playing tips and other aspects of ＂fireworks＂ .

Simple but Dominant： How to Re-shine Depeche Mode on Album Covers After 80＇s

The aim of this paper is to analyze the album covers of English band Depeche Mode after 80＇s according to the principles of graphic design. Established in 1980, the musical style of the band was turned from synth-pop to new wave, from new wave to electronic, dance, and alternative-rock in decades, but their message stayed as it was： A non-hypocritical, humanist, and decent manner against what is wrong and in love sincerely. As a graphic design product, album covers are pre-print design solutions of two dimensional surfaces. Graphic design, as a design field, has its own elements and principles. Visual elements and typography are the two components which should unite with the help of the six main principles which are： unity/harmony; balance; hierarchy; scale/proportion; dominance/emphasis; and similarity and contrast. All album covers of Depeche Mode after 80＇s were designed in a simple but dominant way in order to form a unique style. On every album cover, there are huge color, size, tone, and location contrasts which concluded in simple domination; domination of a non-hypocritical, humanist, and decent manner against what is wrong and in love sincerely.

Influence of Social Determinants in Preference of Public Audience at Music Performances in the Republic of Macedonia

This paper displays the results of a survey of public music performances held during 2010 in Skopje, the capital of the Republic of Macedonia. Study of the audience of public musical events was limited only to the number of visitors. Field research included 653 musical events with a total of 545,340 visitors grouped into eight categories according to the preference by genres of music preference, age, status symbol, origin of the performers, space, and organizers. Our experience in monitoring public musical events through personal presence, the recorded materials, and the continuous monitoring of information from electronic and print media, enabled us to record events and to build some initial comments and assumptions about the structure of the audience and music preference. We have chosen to consider the impact of the sociological determinants on the preference of the audience in the public musical performances through the music genres, the age, the status symbol, the origin of the performers, the area of maintenance, and the organizers of musical events. According to the genre distribution, classical music events prevail, and the greatest numbers of visitors are registered at the pop rock concerts. The structure of the audience according to the age varies depending on the musical genre, so the widest age structure covers the events of pop rock music.

Tonal Noise Prediction of an Automotive Engine Cooling Fan： Comparison between Analytical Models and Acoustic Analogy Results

Valeo, involved in engine cooling fan system design for many years, is interested in noise prediction tools for axial fans. Thus, this paper describes a two-part study of tonal noise computation. The first part deals with the prediction of tonal noise using analytical models. As for the second part, it describes a hybrid approach for predicting tonal noise where the sources are extracted from an Unsteady Reynolds-Averaged Naviers-Stocks （URANS） simulation and then propagated into the far, free field using the Ffowcs Williams and Hawkings＇ acoustic analogy. The computational domain is meshed with 46 million polyhedral elements and the simulation takes into account the exact geometry of the rotor blades, the stator blades and the shroud. The results from the first part show that analytical models can be used for comparisons between different fan geometries, but are unable to provide accurate noise predictions compared to experimental results. The simulation shows non-periodic blade loading over a whole fan revolution, and different blade loading between the blades. This introduces some bias in the assessment of the acoustic performance of the fan. Overall, the results from the hybrid method are in accordance with the experimental results.

Analysis on the Characteristics of Singing Liao Songs with Male Voice in Pingguo of Guangxi

Liao songs are the cultural and artistic products brewed by the people of Zhuang ethnic minority for thousand years. In this paper, the style and characteristics of singing Zhuang ethnic minority＇s Liao songs with male＇s two-part voice in Guangxi are mainly introduced through an analysis of vocal music and the study on the performance forms, singing language characteristics, and vocal music and resonance is mainly included, and also the important significance of singing Zhuang ethnic minority＇s Liao songs with male＇s two-part voice is discussed. Also, it is compared with the modern Chinese folk singing styles.

Shock Wave Boundary Layer Interaction on Suction Side of Compressor Profile in Single Passage Test Section

The shock wave boundary layer interaction on the suction side of transonic compressor blade is one of the main objectives of TFAST project(Transition Location Effect on Shock Wave Boundary Layer Interaction).In order to investigate the flow structure on the suction side of a profile,a design of a generic test section in linear transonic wind tunnel was proposed.The experimental and numerical results for the flow structure investigations are shown for the flow conditions as the existing ones on the suction side of the compressor profile.Near the sidewalls the suction slots are applied for the corner flow structure control.It allows to control the Axial Velocity Density Ratio(AVDR),important parameter for compressor cascade investigations.Numerical results for Explicit Algebraic Reynolds Stress Model with transition modeling are compared with oil flow visualization,schlieren and Pressure Sensitive Paint.Boundary layer transition location is detected by Temperature Sensitive Paint.

A noise cross PSD estimator for dual-microphone speech enhancement based on minimum statistics

Some two-microphone noise reduction techniques that work in the frequency domain exploit coherence function between two noisy signals. They have shown good results when noise signals on two sensors are uncorrelated, but their per-formance decreases with correlated noises. Coherence based methods can be improved when the cross power spectral density (CPSD) of correlated noise signals is available. In this paper, we propose a new method for estimation of the CPSD of the noise, which is based on the minimum tracking technique. Despite the fact that the proposed estimator does not need to implement a voice activity detector (VAD), its performance is comparable to a CPSD estimator that uses an ideal VAD.

Case of post-stroke depression

By adopting the psychosomatic therapy, the author treated 1 case of post-stroke depression through applying traditional acupuncture, acupoint injection combined with TCM five-element music therapy. After treatment, the neurological functions of the patient obviously recovered, Hamilton Depression（HAMD）Scale（17 items） score reduced, the levels of tumor necrosis factor and hypersensitive C-reactive protein both declined, and all the indicators were improved significantly, indicating that the curative effect of acupuncture combined with TCM five-element music therapy on this PSD patient was significant, and this treatment method was worthy of further exploration.

The Effect of Non-equilibrium Condensation on the Drag Coefficient in a Transonic Airfoil Flow

In this study, a transonic flow past NACA0012 profile at angle of attack α=0^0 whose aspect ratio AR is 1.0 with non-equilibrium condensation is analyzed by numerical analysis using a TVD scheme and is investigated using an intermittent indraft type supersonic wind tunnel. Transonic flows of 0.78-0.90 in free stream Mach number with the variations of the stagnation relative humidity（φ0） are tested. For the same free stream Mach number, the increase in φ0 causes decrease in the drag coefficient of profile which is composed of the drag components of form, viscous and wave. In the case of the same Moo and To, for more than φ0=30%, despite the irreversibility of process in non-equilibrium condensation, the drag by shock wave decreases considerably with the increase of φ0. On the other hand, it shows that the effect of condensation on the drag coefficients of form and viscous is negligible. As an example, the decreasing rate in the drag coefficient of profile caused by the influence of non-equilibrium condensation for the case of M∞=0.9 and φ0 =50% amounts to 34%. Also, it were turned out that the size of supersonic bubble （that is, the maximum height of supersonic zone） and the deviation of pressure coefficient from the value for M=1 decrease with the increase of φ0 for the same M∞.

Comparative study on aerodynamic heating under perfect and nonequilibrium hypersonic flows

In this study, comparative heat flux measurements for a sharp cone model were conducted by utilizing a high enthalpy shock tunnel JF-10 and a large-scale shock tunnel JF-12, responsible for providing nonequilibrium and perfect gas flows, respectively. Experiments were performed at the Key Laboratory of High Temperature Gas Dynamics(LHD), Institute of Mechanics, Chinese Academy of Sciences. Corresponding numerical simulations were also conducted in effort to better understand the phenomena accompanying in these experiments. By assessing the consistency and accuracy of all the data gathered during this study, a detailed comparison of sharp cone heat transfer under a totally different kind of freestream conditions was build and analyzed. One specific parameter, defined as the product of the Stanton number and the square root of the Reynold number, was found to be more characteristic for the aerodynamic heating phenomena encountered in hypersonic flight. Adequate use of said parameter practically eliminates the variability caused by the deferent flow conditions, regardless of whether the flow is in dissociation or the boundary condition is catalytic. Essentially, the parameter identified in this study reduces the amount of ground experimental data necessary and eases data extrapolation to flight.

Numerical analysis on the heat transfer of three types of nozzles for the hypersonic long-run wind tunnel

The hypersonic long-run scramjet test tunnel is one of the key ground facilities for the studies of ramjet/scramjet and hypersonic thermal management.Due to the significantly large heat loading,the nozzle of the tunnel facility demands effective cooling protection.In this work,the two-dimensional,three-dimensional and axisymmetric Mach 6.5 nozzles at an inlet total temperature of 1840 K and a total pressure of 6.4 MPa were studied with main focuses on the properties of aerodynamic heating of nozzles.The present work aims to provide insights into the design of an effective cooling system for the nozzle and other components of the hypersonic long-run wind tunnel.

A Study on High Subsonic Airfoil Flows in Relatively High Reynolds Number by Using OpenFOAM

In the present study,numerical calculations of the flow-field around the airfoil model are performed by using the OpenFOAM in high subsonic flows.The airfoil model is NACA 64A010.The maximum thickness is 10 % of the chord length.The SonicFOAM and the RhoCentralFOAM are selected as the solver in high subsonic flows.The grid point is 158,000 and the Mach numbers are 0.277 and 0.569 respectively.The CFD data are compared with the experimental data performed by the cryogenic wind tunnel in the past.The results are as follows.The numerical results of the pressure coefficient distribution on the model surface calculated by the SonicFOAM solver showed good agreement with the experimental data measured by the cryogenic wind tunnel.And the data calculated by the SonicFOAM have the capability for the quantitative comparison of the experimental data at low angle of attack.

A reduced-order-model-based multiple-in multiple-out gust alleviation control law design method in transonic flow

Gust alleviation is very important to a large flexible aircraft.A nonlinear low-order aerodynamic state space model is required to model the nonlinear aeroelastic responses due to gust.Based on the proper orthogonal decomposition method,a reduced order modeling of gust loads was proposed.And then the open-loop and closed-loop reduced order state space model for the transonic aeroelastic system was developed.The static output feed back control scheme was used to design a simple multiple-in multiple-out(MIMO)gust alleviation control law.The control law was demonstrated with the Goland+wing model with four control surfaces.The simulation results of different discrete gusts show the capability and good performance of the designed MIMO controller in transonic gust alleviation.