Simulation of vehicle interior wind noise at low frequencies: a case study

2008 ◽  
Vol 123 (5) ◽  
pp. 3452-3452
Author(s):  
Robert Powell ◽  
Bijan Khatib‐Shahidi
Keyword(s):  
Vehicle Interior ◽  
Wind Noise ◽  
Low Frequencies

scholarly journals Real-Time Process Monitoring Based on Multivariate Control Chart for Anomalies Driven by Frequency Signal via Sound and Electrocardiography Cases

Processes ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1510
Author(s):  
Chih-Hung Jen ◽  
Chien-Chih Wang
Keyword(s):  
Real Time ◽  
Process Monitoring ◽  
Sound Frequency ◽  
Detection Accuracy ◽  
Control Line ◽  
Time Process ◽  
Intrinsic Mode Functions ◽  
Low Frequencies ◽  
Linear Discriminant

Recent developments in network technologies have led to the application of cloud computing and big data analysis to industrial automation. However, the automation of process monitoring still has numerous issues that need to be addressed. Traditionally, offline statistical processes are generally used for process monitoring; thus, problems are often detected too late. This study focused on the construction of an automated process monitoring system based on sound and vibration frequency signals. First, empirical mode decomposition was combined with intrinsic mode functions to construct different sound frequency combinations and differentiate sound frequencies according to anomalies. Then, linear discriminant analysis (LDA) was adopted to classify abnormal and normal sound frequency signals, and a control line was constructed to monitor the sound frequency. In a case study, the proposed method was applied to detect abnormal sounds at high and low frequencies, and a detection accuracy of over 90% was realized. In another case study, the proposed method was applied to analyze electrocardiography signals and was similarly able to identify abnormal situations. Thus, the proposed method can be applied to real-time process monitoring and the detection of abnormalities with high accuracy in various situations.

Modularization of Work Tasks for Global Engineering

2005 ◽  
Author(s):  
Peter Leung ◽  
Kosuke Ishii ◽  
Jan Benson
Keyword(s):  
Interior Design ◽  
Design System ◽  
Distributed Teams ◽  
Future Research ◽  
Functional Requirements ◽  
Vehicle Interior ◽  
Design Work ◽  
Global Engineering ◽  
Work Tasks

This paper introduces a methodology that guides the modularization of work task for global engineering. Global engineering is a new collaboration model of co-developing engineering design systems with distributed teams. We consider the decision of allocating subsystem designs to engineering teams as modularization of work tasks. Previous efforts have reviewed the different approaches to analyzing product modularization, but few studies have investigated developing a methodology that focuses on process applications. We begin this paper with an overview of current modularization methods and of the definitions of Global Engineering. Then we present the three-step modularization methodology in detail: 1.) decompose the design system and its functional specifications by a flow down technique, 2.) identify the couplings between the system parts and the functional requirements, and plot the interactions in a matrix, and 3.) modularize design work based on the identified couplings for worksharing. As a case study, we apply the method to a vehicle interior design. We conclude the paper by discussing the case study findings and the appropriate application of this analysis. We also explain the methodology’s limitations and propose future research opportunities.

Experimental Evaluation of Wind Noise Sources: A Case Study

1999 ◽  
Author(s):  
William B. Coney ◽  
Jen Y. Her ◽  
Keith Tomaszewicz ◽  
Kevin Y. Zhang ◽  
James A. Moore
Keyword(s):  
Experimental Evaluation ◽  
Noise Sources ◽  
Wind Noise

Treatment of a Case of Cerebral Palsy with Hearing Impairment

1972 ◽  
Vol 37 (3) ◽  
pp. 373-378 ◽  
Author(s):  
James L. Fitch
Keyword(s):  
Cerebral Palsy ◽  
Hearing Impairment ◽  
Grade Level ◽  
Special Class ◽  
Mentally Retarded ◽  
First Grade ◽  
Residual Hearing ◽  
Low Frequencies ◽  
Custodial Care

The case study of an 11-year-old girl with cerebral palsy, athetoid type, is reported. The girl had been diagnosed as severely mentally retarded, and placement in a residential institution with custodial care had been recommended. The girl was found to have extensive hearing impairment, with residual hearing in the low frequencies. Hearing testing was complicated by uncontrolled, extraneous movement. The loss was identified only after her understanding of nonverbal concepts was found to be well developed. A program of instruction was presented both orally and manually. In eight months the girl had a manual vocabulary in excess of 500 words and was functioning in reading and arithmetic at a mid-first-grade level. Placement in a special class for the deaf followed.

Numerical investigation on the contribution of underbody flow-induced noise on vehicle interior noise

2021 ◽  
pp. 095440702110044
Author(s):  
Yiping Wang ◽  
Mintao Du ◽  
Chuqi Su ◽  
Wenguang Wu
Keyword(s):  
Noise Source ◽  
Interior Noise ◽  
Experimental Result ◽  
Aerodynamic Noise ◽  
Acoustic Response ◽  
Vehicle Model ◽  
Vehicle Interior ◽  
Wind Noise ◽  
Flow Induced Noise ◽  
Computational Fluid Dynamics Cfd

Aerodynamic noise transmitted through greenhouse panels and sealing often dominates the higher frequencies of the interior noise level, whereas the underbody area contributes mainly to low and middle frequencies. A method that unsteady Computational Fluid Dynamics (CFD) for exterior airflow combined with Finite Element Method (FEM) for interior acoustic response was used. To validate the accuracy of this method, the interior wind noise of a simplified vehicle model proposed by Hyundai was computed. The comparison between the computational and experimental result showed that this method had enough accuracy to compute the interior wind noise induced by the exterior flow field. Then, the same method was used to compute the wind noise transmitted through the underbody of a passenger car. The characteristic of the noise source and noise inside the cabin was revealed, and the contribution of underbody flow-induced noise to the interior noise was also investigated. Finally, the influence of the underbody panels thicknesses on the interior wind noise was evaluated.

Looming Deficits: Textile Production Specialization in Postclassic Mesoamerica

2019 ◽  
Vol 30 (4) ◽  
pp. 780-797 ◽  
Author(s):  
Angela C. Huster
Keyword(s):  
Strong Dependence ◽  
Craft Production ◽  
Textile Production ◽  
Low Frequencies ◽  
Regional Specialization ◽  
Self Sufficiency ◽  
Early Postclassic ◽  
Late Postclassic ◽  
Low Levels

Using textile production in Postclassic Western Mesoamerica as a case study, this article explores how to differentiate low levels of craft production caused by household provisioning from low levels of craft production due to market reliance and regional specialization. I use a sample of 52 excavated site/phase components to establish baselines for the intensity of production and to evaluate whether participation in the market allowed craftspeople in some regions to underproduce textiles relative to local needs. Highland and lowland sites have comparable low frequencies of spindle whorls during the Early Postclassic, which I interpret as characteristic of household self-sufficiency. Whorl frequencies increase above this baseline earlier and to a higher degree in lowland sites than in highland sites. During the Late Postclassic, some regions may have formed pairs of over- and underproduction zones linked by the market. Because of changes in spinning technology, it is not possible to extrapolate the results of this study to earlier time periods. I then present data from Calixtlahuaca as an example of how macroregional data can be used to interpret craft production at a particular site. Textile production at Calixtlahuaca was generally low, but this was more likely a function of a strong dependence on maguey fiber, rather than underproduction caused by a reliance on the market.

Integration of broadband seismic data into reservoir characterization workflows: A case study from the Campos Basin, Brazil

2018 ◽  
Vol 6 (1) ◽  
pp. T145-T161 ◽  
Author(s):  
Ekaterina Kneller ◽  
Manuel Peiro
Keyword(s):  
Reservoir Characterization ◽  
Petroleum Exploration ◽  
Full Potential ◽  
Reservoir Properties ◽  
Data Set ◽  
Low Frequencies ◽  
Campos Basin ◽  
Elastic Inversion

Towed-streamer marine broadband data have been key contributors to recent petroleum exploration history, in new frontiers and in mature basins around the world. They have improved the characterization of reservoirs by reducing the uncertainty in structural and stratigraphic interpretation and by providing more quantitative estimates of reservoir properties. Dedicated acquisition, processing, and quality control (QC) methods have been developed to capitalize on the broad bandwidth of the data and allow their rapid integration into reservoir models. Using a variable-depth steamer data set acquired in the Campos Basin, Brazil, we determine that particular care that should be taken when processing and inverting broadband data to realize their full potential for reservoir interpretation and uncertainty management in the reservoir model. In particular, we determine the QC implemented and interpretative processing approach used to monitor data improvements during processing and preconditioning for elastic inversion. In addition, we evaluate the importance of properly modeling the low frequencies during wavelet estimation. We find the benefits of carefully processed broadband data for structural interpretation and describe the application of acoustic and elastic inversions cascaded with Bayesian lithofacies classification, to provide clear interpretative products with which we were able to demonstrate a reduction in the uncertainty of the prediction and characterization of Santonian oil sandstones in the Campos Basin.

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