scholarly journals A Numerical Approach for Sound Quality of Vehicle Doors

2020 ◽  
Vol 25 (1) ◽  
pp. 9-16
Author(s):  
Erkut Yalçın ◽  
Halil Bilal ◽  
Ayhan Yağcı ◽  
Haluk Erol

A Vibro-Acoustic Finite Element Method (FEM) model capable of calculating the transient sound pressure generated by the door slam of a vehicle was developed in this study. A design sensitivity analysis (DSA) was performed for investigating the effects of major design variables on the related sound quality metrics. The methodology was developed using a sedan-car and its FEM model. This paper shows that a Computer Aided Engineering (CAE) model can be used as a rather powerful tool for giving design change decisions for the door components from sound quality point of view during vehicle body development according to psychoacoustic parameters.

2021 ◽  
Vol 17 (2) ◽  
pp. 198-205
Author(s):  
Leehwa Park ◽  
Soo Hee Oh

Purpose: Recent bimodal studies identified a lack of bimodal evaluation and fitting protocols to improve bimodal benefits. The purpose of this study is to measure bimodal benefits in speech and sound quality recognition and identify bimodal fitting issues with adult cochlear implant listeners to establish bimodal fitting guidelines and evaluation protocol.Methods: A total of 20 adult cochlear implant users were participated in this study. The experimental procedures included basic evaluation, hearing aid evaluation, and bimodal benefits evaluation. In order to evaluate bimodal benefits, speech and sound quality recognition tests were performed. Matrix sentences in quiet and noise (5 and 10 dB sound pressure level), consonant-vowel-consonant words, and story comprehension tasks were provided. Participants judged sound qualities for six sound quality dimensions and a tester performed real ear measurements to verify hearing aid gains.Results: Results showed that bimodal listeners had some bimodal benefits in the sentence and monosyllabic word recognition in quiet. The benefits of sound quality judgments were also observed for six sound quality dimensions. Bimodal cochlear implant listeners of this study demonstrated less real-ear insertion gains than target gains across test frequencies.Conclusion: Speech and sound quality recognition tests are useful tools to measure bimodal benefits. Additional care for bimodal listeners is needed to optimize bimodal fitting and improve the quality of bimodal hearing aid fitting services.


1997 ◽  
Vol 25 (1) ◽  
pp. 29-42 ◽  
Author(s):  
E-J. Ni ◽  
D. S. Snyder ◽  
G. F. Walton ◽  
N. E. Mallard ◽  
G. E. Barron ◽  
...  

Abstract As a general trend, vehicle sound quality has significantly improved in recent years. This is primarily due to improved body structure and powertrain design. As demand for better vehicle sound quality increases, it is important to study all possible noise sources contributing to noise, vibration, and harshness (NVH). Tire vibration has long been recognized as a source of airborne noise. Some effects of wheel design on tire noise have also been well understood for sometime. But the dynamic interaction between tire and wheel designs and its effect on vehicle NVH, although frequently observed for many years, has only recently been identified in the 200–350 Hz frequency range. Different wheels can produce perceptible differences in vehicle interior sound pressure levels in a road test. Hence, the authors have developed a process to quantify and reduce noise caused by a vibrating tire/wheel assembly. This paper discusses the general flow of the process, which begins with the identification of NVH issues on a total vehicle level. Modeling and optimization of the aluminum wheel was chosen as the focus of this project for two reasons. First, the interior sound pressure level (SPL) around 285 Hz is about 5–7 dBA higher in a vehicle equipped with aluminum wheels rather than a steel design. Second, modifying the wheel is far more economical and faster due to its simplicity of design than the complexity of either the vehicle body structure or a tire.


1992 ◽  
Vol 35 (1) ◽  
pp. 175-185 ◽  
Author(s):  
Todd W. Fortune ◽  
David A. Preves

Clinical measurements of the loudness discomfort level (LDL) are generally performed while the subject listens to a particular stimulus presented from an audiometer through headphones (AUD-HP). The assumption in clinical practice has been that the sound pressure level (SPL) corresponding to the sensation of loudness discomfort under AUD-HP conditions will be the same as that corresponding to LDL with the hearing aid. This assumption ignores the fact that the distortion produced by a saturating hearing aid could have an influence on the sensation of loudness. To examine these issues, 5 hearing-impaired subjects were each fit with four linear hearing aids, each having a different saturation sound pressure level (SSPL90). Probe-tube microphone measurements of ear canal SPL at LDL were made while the subjects listened to continuous discourse in quiet under aided and AUD-HP conditions. Also using continuous discourse, real-ear coherence measures were made at various output sound pressure levels near LDL. All four hearing aid types produced mean LDLs that were lower than those obtained under AUD-HP conditions. Those hearing aids with higher SSPL90 produced significantly higher LDLs than hearing aids with lower SSPL90. A significant negative correlation was found between real-ear SPL and real-ear coherence. Quality judgments made at LDL indicated that sound quality of hearing aids with higher SSPL90 was preferred to that of hearing aids with lower SSPL90. Possible fitting implications regarding the setting of SSPL90 from AUD-HP LDL measures are discussed.


2020 ◽  
Vol 7 (2) ◽  
pp. 34-41
Author(s):  
VLADIMIR NIKONOV ◽  
◽  
ANTON ZOBOV ◽  

The construction and selection of a suitable bijective function, that is, substitution, is now becoming an important applied task, particularly for building block encryption systems. Many articles have suggested using different approaches to determining the quality of substitution, but most of them are highly computationally complex. The solution of this problem will significantly expand the range of methods for constructing and analyzing scheme in information protection systems. The purpose of research is to find easily measurable characteristics of substitutions, allowing to evaluate their quality, and also measures of the proximity of a particular substitutions to a random one, or its distance from it. For this purpose, several characteristics were proposed in this work: difference and polynomial, and their mathematical expectation was found, as well as variance for the difference characteristic. This allows us to make a conclusion about its quality by comparing the result of calculating the characteristic for a particular substitution with the calculated mathematical expectation. From a computational point of view, the thesises of the article are of exceptional interest due to the simplicity of the algorithm for quantifying the quality of bijective function substitutions. By its nature, the operation of calculating the difference characteristic carries out a simple summation of integer terms in a fixed and small range. Such an operation, both in the modern and in the prospective element base, is embedded in the logic of a wide range of functional elements, especially when implementing computational actions in the optical range, or on other carriers related to the field of nanotechnology.


2005 ◽  
Vol 55 (2) ◽  
pp. 201-221 ◽  
Author(s):  
Andrea Szalavetz

This paper discusses the relation between the quality and quantity indicators of physical capital and modernisation. While international academic literature emphasises the role of intangible factors enabling technology generation and absorption rather than that of physical capital accumulation, this paper argues that the quantity and quality of physical capital are important modernisation factors, particularly in the case of small, undercapitalised countries that recently integrated into the world economy. The paper shows that in Hungary, as opposed to developed countries, the technological upgrading of capital assets was not necessarily accompanied by the upgrading of human capital i.e. the thesis of capital skill complementarity did not apply to the first decade of transformation and capital accumulation in Hungary. Finally, the paper shows that there are large differences between the average technological levels of individual industries. The dualism of the Hungarian economy, which is also manifest in terms of differences in the size of individual industries' technological gaps, is a disadvantage from the point of view of competitiveness. The increasing differences in the size of the technological gaps can be explained not only with industry-specific factors, but also with the weakness of technology and regional development policies, as well as with institutional deficiencies.


Author(s):  
Trapti Sharma ◽  
R. P. Nagar ◽  
R. C. Gaur ◽  
Pooja Gupta ◽  
Charanjit Kaur

In Rajasthan state the ground waters of some areas like Ramganj-mandi, Morak, Barmer, Jaisalmer, Chittor and Udaipur etc. are susceptible from drinking point of view.To test the quality of groundwater in Chittor district 14, ground water samples were collected from various places and analyzed for pH, E.C., Fluoride and Nitrate parameters by standard methods (A.P.H. A., Washington, USA, 1995). The study revealed that none of the ground waters was found suitable completely from drinking point of view. Some are having electrical conductivity > 1.4 dS/m, some are having pH >8.5, some area having fluoride >1.5 ppm and some are having nitrate>45 ppm. These are the limits of various parameters permitted by various International authorities like Bureau of Indian Standard, Indian Council of Medical Research,world health Organization etc. for drinking waters. So, it is recommended to the residents of above areas to use water for drinking purpose only after reverse osmosis or adopting suitable method of removing excess of Fluoride and Nitrate for drinking water to avoid unwanted pathogenic diseases harmful for human health.


2017 ◽  
Vol 14 (2) ◽  
pp. 1
Author(s):  
Sina Saeedy ◽  
Mojtaba Amiri ◽  
Mohammad Mahdi Zolfagharzadeh ◽  
Mohammad Rahim Eyvazi

Quality of life and satisfaction with life as tightly interconnected concepts have become of much importance in the urbanism era. No doubt, it is one of the most important goals of every human society to enhance a citizen’s quality of life and to increase their satisfaction with life. However, there are many signs which demonstrate the low level of life satisfaction of Iranian citizens especially among the youth. Thus, considering the temporal concept of life satisfaction, this research aims to make a futures study in this field. Therefore, using a mixed model and employing research methods from futures studies, life satisfaction among the students of the University of Tehran were measured and their views on this subject investigated. Both quantitative and qualitative data were analysed together in order to test the hypotheses and to address the research questions on the youth discontentment with quality of life. Findings showed that the level of life satisfaction among students is relatively low and their image of the future is not positive and not optimistic. These views were elicited and discussed in the social, economic, political, environmental and technological perspectives. Keywords:  futures studies, quality of life, satisfaction with life, youth


2018 ◽  
Author(s):  
Мария Григорьевна Алпатова ◽  
Мария Игоревна Щеглова ◽  
Elmira Kalybaevna Adil’bekova ◽  
Nuradin Alibaev ◽  
Arunas Svitojus

The conference is a major international forum for analyzing and discussing trends and approaches in research in the field of basic science and applied research. We provide a platform for discussions on innovative, theoretical and empirical research. The form of the conference: in absentia, without specifying the form in the collection of articles. Working languages: Russian, English Doctors and candidates of science, scientists, specialists of various profiles and directions, applicants for academic degrees, teachers, graduate students, undergraduates, students are invited to participate in the conference. There is one blind verification process in the journal. All articles will be initially evaluated by the editor for compliance with the journal. Manuscripts that are considered appropriate are then usually sent to at least two independent peer reviewers to assess the scientific quality of the article. The editor is responsible for the final decision on whether to accept or reject the article. The editor's decision is final. The main criterion used in assessing the manuscript submitted to the journal is: uniqueness or innovation in the work from the point of view of the methodology being developed and / or its application to a problem of particular importance in the public sector or service sector and / or the setting in which the efforts, for example, in the developing region of the world. That is, the very model / methodology, application and context of problems, at least one of them must be unique and important. Additional criteria considered in the consideration of the submitted document are its accuracy, organization / presentation (ie logical flow) and recording quality.


2019 ◽  
Author(s):  
Изабелла Станиславовна Чибисова ◽  
Диана Ильгизаровна Шарипова ◽  
Альфия Галиевна Зулькарнаева ◽  
Ксения Александровна Дулова ◽  
Садег Амирзадеган ◽  
...  

The conference is a major international forum for analyzing and discussing trends and approaches in research in the field of basic science and applied research. We provide a platform for discussions on innovative, theoretical and empirical research. The form of the conference: in absentia, without specifying the form in the collection of articles. Working languages: Russian, English Doctors and candidates of science, scientists, specialists of various profiles and directions, applicants for academic degrees, teachers, graduate students, undergraduates, students are invited to participate in the conference. There is one blind verification process in the journal. All articles will be initially evaluated by the editor for compliance with the journal. Manuscripts that are considered appropriate are then usually sent to at least two independent peer reviewers to assess the scientific quality of the article. The editor is responsible for the final decision on whether to accept or reject the article. The editor's decision is final. The main criterion used in assessing the manuscript submitted to the journal is: uniqueness or innovation in the work from the point of view of the methodology being developed and / or its application to a problem of particular importance in the public sector or service sector and / or the setting in which the efforts, for example, in the developing region of the world. That is, the very model / methodology, application and context of problems, at least one of them must be unique and important. Additional criteria considered in the consideration of the submitted document are its accuracy, organization / presentation (ie logical flow) and recording quality.


1990 ◽  
Vol 22 (1-2) ◽  
pp. 347-352 ◽  
Author(s):  
C. Paffoni ◽  
B. Védry ◽  
M. Gousailles

The Paris Metropolitan area, which contains over eight million inhabitants, has a daily output of about 3 M cu.meters of wastewater, the purification of which is achieved by SIAAP (Paris Metropolitan Area Sewage Service) in both Achères and Valenton plants. The carbon pollution is eliminated from over 2 M cu.m/day at Achères. In order to improve the quality of output water, its tertiary nitrification in fixed-bed reactors has been contemplated. The BIOFOR (Degremont) and BIOCARBONE (OTV) processes could be tested in semi-industrial pilot reactors at the CRITER research center of SIAAP. At a reference temperature of 13°C, the removed load is approximately 0.5 kg N NH4/m3.day. From a practical point of view, it may be asserted that in such operating conditions as should be at the Achères plant, one cubic meter of filter can handle the tertiary nitification of one cubic meter of purified water per hour at an effluent temperature of 13°C.


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