Comparative Field Measurements of Tire Pavement Noise of Selected Texas Pavements

1998 ◽  
Vol 1626 (1) ◽  
pp. 78-84 ◽  
Author(s):  
Michael T. Mcnerney ◽  
B.J. Landsberger ◽  
Tracy Turen ◽  
Albert Pandelides
Keyword(s):  
South Africa ◽  
Research Effort ◽  
Traffic Noise ◽  
Test Procedure ◽  
Field Measurements ◽  
Field Testing ◽  
The United States ◽  
Noise Barriers ◽  
Set Up ◽  
Pavement Noise

The effects of traffic noise are a serious concern in the United States and in the rest of the world. One significant component of traffic noise is tire-pavement interaction. If tire-pavement noise can be reduced at the source instead of through the use of traffic noise barriers set up to protect individual receivers, then potential savings can accrue. This research effort conducted field testing on 15 different pavement types found in Texas, and on six pavement types found in South Africa. A test procedure was developed with roadside microphones and microphones mounted on a test trailer to record and analyze the differences in tire-pavement noise. The test procedure was designed to develop comparisons of pavements while other variables were kept constant. The results, measured on the standard A-weighted scale, indicated for the 15 test pavements in Texas a difference of roadside noise levels of up to 7 dBA. Additionally, a roadside noise level of one pavement measured in South Africa was more than 2 dBA quieter than any Texas pavement.

Carter on Apartheid

Worldview ◽  
1977 ◽  
Vol 20 (5) ◽  
pp. 4-7
Author(s):  
Ross K. Baker
Keyword(s):  
United States ◽  
South Africa ◽  
Assembly Line ◽  
The United States ◽  
Fiftieth Anniversary ◽  
Woodrow Wilson ◽  
Henry Ford ◽  
The Law ◽  
Set Up ◽  
Battle Of Gettysburg

In 1913, when Woodrow Wilson was assuming the duties of President of the United States, Joseph Stalin was in exile in Siberia and Lenin in Galicia. When Union and Confederate veterans were meeting to commemorate the fiftieth anniversary of the Battle of Gettysburg and Henry Ford was about to set up the first modern assembly line, the newly established Union of South Africa promulgated the Natives Land Act. A world preoccupied with the decay of great empires and apprehensive about the onset of world conflict was only dimly aware of this law enacted in a distant corner of a remote continent. The law prescribed the apportionment of territory of the Union into areas of exclusive settlement by whites and blacks.

scholarly journals Field Testing of Cavity Ring-Down Spectroscopy Analyzers Measuring Carbon Dioxide and Water Vapor

2012 ◽  
Vol 29 (3) ◽  
pp. 397-406 ◽  
Author(s):  
Scott J. Richardson ◽  
Natasha L. Miles ◽  
Kenneth J. Davis ◽  
Eric R. Crosson ◽  
Chris W. Rella ◽  
...  
Keyword(s):  
Water Vapor ◽  
Field Measurements ◽  
Field Testing ◽  
The United States ◽  
Upper Midwest ◽  
Cavity Ring Down Spectroscopy ◽  
The North ◽  
Improved Stability ◽  
Field Deployment ◽  
Cavity Ring Down

Abstract Prevalent methods for making high-accuracy tower-based measurements of the CO2 mixing ratio, notably nondispersive infrared spectroscopy (NDIR), require frequent system calibration and sample drying. Wavelength-scanned cavity ring-down spectroscopy (WS-CRDS) is an emerging laser-based technique with the advantages of improved stability and concurrent water vapor measurements. Results are presented from 30 months of field measurements from WS-CRDS systems at five sites in the upper Midwest of the United States. These systems were deployed in support of the North American Carbon Program’s Mid-Continent Intensive (MCI) from May 2007 to November 2009. Excluding one site, 2σ of quasi-daily magnitudes of the drifts, before applying field calibrations, are less than 0.38 ppm over the entire 30-month field deployment. After applying field calibrations using known tanks sampled every 20 h, residuals from known values are, depending on site, from 0.02 ±0.14 to 0.17 ±0.07 ppm. Eight months of WS-CRDS measurements collocated with a National Oceanographic and Atmospheric Administrations (NOAA)/Earth System Research Laboratory (ESRL) NDIR system at West Branch, Iowa, show median daytime-only differences of −0.13 ±0.63 ppm on a daily time scale.

Determination of the Best Areas Behind the Noise Barriers with the Highest Performance by using a Mathematical Model

2020 ◽  
pp. 2150015
Author(s):  
M. R. Monazzam ◽  
N. Mansouri ◽  
Hamidreza Pouragha ◽  
Mahsa Naserpour
Keyword(s):  
Mathematical Model ◽  
Traffic Noise ◽  
Field Measurements ◽  
Noise Pollution ◽  
Center Frequency ◽  
Wide Field ◽  
Noise Barriers ◽  
Destructive Effect ◽  
Indirect Path ◽  
Noise Frequency

Traffic noise barriers are one of the most important ways of environmental noise pollution control. Profiled barriers are one of the most successful noise control screens. A simple mathematical model representation of the zones behind rigid and absorbent barriers with the highest insertion loss using the destructive effect of the indirect path via barrier image is introduced. The results are compared with the results of a verified two-dimensional (2D) BEM in a wide field behind those barriers. Field measurements for the model near a highway in a megacity were also tested. A very good agreement between the results has been achieved. In this method, effective height is used for any different profile barrier. Since the highway dominant noise frequency was found to be at 125 Hz 1/3-octave band center frequency, the presented model in this study showed that the best place for installing a T-shaped barrier is 10.5[Formula: see text]m from the target receiver. The introduced model is very simple and fast and could be used for choosing the best location of profiled barriers to achieve the highest performance with no additional cost.

Analysis of Strategies To Control Traffic Noise at the Source: Implications for Policy Makers

1998 ◽  
Vol 1626 (1) ◽  
pp. 41-48 ◽  
Author(s):  
Lloyd A. Herman
Keyword(s):  
Noise Control ◽  
Control Strategies ◽  
Traffic Noise ◽  
The United States ◽  
Market Forces ◽  
Policy Makers ◽  
Vehicle Noise ◽  
Cooling Fan ◽  
Control Traffic ◽  
Pavement Noise

Traffic noise control strategies that reduce traffic noise at the source were identified. The strategies were grouped according to the vehicle noise sub-sources: engine, intake air, exhaust, cooling fan, transmission/driveline, and tire/pavement. Examples of the strategies and recent advancements in vehicle noise control are given. The analysis yielded a number of implications for policy makers. In the United States, market forces are currently fostering technological advancements to reduce most of the vehicle noise subsources. However, the reduction of tire/pavement noise, the dominant subsource at freeway speeds, is currently benefiting little from market forces and may be hindered in the future by trends in passenger car tires. Policies and regulations, where warranted, should be aimed at reducing tire/pavement noise through a concerted effort on the part of both tire and pavement industries as well as transportation agencies.

Performance of Noise Barriers with Absorptive Edge Treatments

2003 ◽  
Vol 1859 (1) ◽  
pp. 53-64
Author(s):  
Sanghoon Suh ◽  
Vincent J. Badagnani ◽  
Luc Mongeau ◽  
J. Stuart Bolton
Keyword(s):  
Traffic Noise ◽  
Field Measurements ◽  
Sound Level ◽  
Noise Model ◽  
Scale Model ◽  
Vertical Edge ◽  
Laboratory Measurements ◽  
Shadow Zone ◽  
Noise Barriers ◽  
Noise Barrier

The installation of sound-absorptive materials near the edge of a noise barrier is known to increase its insertion loss. First, scale-model experiments were performed to compare the performance of barriers that have absorptive edge linings with that of linearly extended, rigid uniform barriers and T-shaped barriers. The issue of effective positioning of the sound-absorptive material was also addressed. It was found that in terms of material use, an absorptive treatment was the most effective treatment for reducing the sound level in the shadow zone for a given barrier height. It was concluded that absorptive edge treatments may offer the opportunity to design effective treatments that could be retrofitted to existing barrier installations to improve their effectiveness. Preliminary field measurements were performed near South Bend, Indiana. The performance of an existing barrier was evaluated. Predictions of its performance made using the FHWA Traffic Noise Model were verified. An acoustical treatment was added to one vertical edge of the highway noise barrier. The results for the performance of the acoustical treatment measured in the field confirmed the trends of the scale-model laboratory measurements.

A reconnaissance of tropical resources during Revolutionary years: the role of the Paris Museum d'Histoire Naturelle

1991 ◽  
Vol 18 (3) ◽  
pp. 333-362 ◽  
Author(s):  
MADELEINE LY-TIO-FANE
Keyword(s):  
South Africa ◽  
Natural History ◽  
Scientific Research ◽  
Extensive Literature ◽  
War Of Independence ◽  
Leading Role ◽  
Scientific Principles ◽  
Set Up ◽  
Joseph Ii

SUMMARY The recent extensive literature on exploration and the resulting scientific advances has failed to highlight the contribution of Austrian enterprise to the study of natural history. The leading role of Joseph II among the neutral powers which assumed the carrying trade of the belligerents during the American War of Independence, furthered the development of collections for the Schönbrunn Park and Gardens which had been set up on scientific principles by his parents. On the conclusion of peace, Joseph entrusted to Professor Maerter a world-encompassing mission in the course of which the Chief Gardener Franz Boos and his assistant Georg Scholl travelled to South Africa to collect plants and animals. Boos pursued the mission to Isle de France and Bourbon (Mauritius and Reunion), conveyed by the then unknown Nicolas Baudin. He worked at the Jardin du Roi, Pamplemousses, with Nicolas Cere, or at Palma with Joseph Francois Charpentier de Cossigny. The linkage of Austrian and French horticultural expertise created a situation fraught with opportunities which were to lead Baudin to the forefront of exploration and scientific research as the century closed in the upheaval of the Revolutionary Wars.

Alexander Hamilton and the Early Republic in Edwardian Imperial Thought

2019 ◽  
Vol 12 (1) ◽  
pp. 28-50 ◽  
Author(s):  
Patrick M. Kirkwood
Keyword(s):  
United States ◽  
South Africa ◽  
Early Republic ◽  
The United States ◽  
Alexander Hamilton ◽  
George Washington ◽  
American Federation ◽  
Treaty Of Versailles ◽  
The Federalist ◽  
The Federalist Papers

In the first decade of the twentieth century, a rising generation of British colonial administrators profoundly altered British usage of American history in imperial debates. In the process, they influenced both South African history and wider British imperial thought. Prior usage of the Revolution and Early Republic in such debates focused on the United States as a cautionary tale, warning against future ‘lost colonies’. Aided by the publication of F. S. Oliver's Alexander Hamilton (1906), administrators in South Africa used the figures of Hamilton and George Washington, the Federalist Papers, and the drafting of the Constitution as an Anglo-exceptionalist model of (modern) self-government. In doing so they applied the lessons of the Early Republic to South Africa, thereby contributing to the formation of the Union of 1910. They then brought their reconception of the United States, and their belief in the need for ‘imperial federation’, back to the metropole. There they fostered growing diplomatic ties with the US while recasting British political history in-light-of the example of American federation. This process of inter-imperial exchange culminated shortly after the signing of the Treaty of Versailles when the Boer Generals Botha and Smuts were publicly presented as Washington and Hamilton reborn.

The use of ICT by SMMEs in a Digital Economy: A case study in Buffalo City Metropolitan in South Africa [Abstract]

10.28945/4314 ◽  
2019 ◽  
Keyword(s):  
South Africa ◽  
Technology Acceptance ◽  
21St Century ◽  
Common Knowledge ◽  
Digital Economy ◽  
Future Research ◽  
Wealth Creation ◽  
Underdeveloped Areas ◽  
And Gender ◽  
Set Up

Aim/Purpose: The goal of this study is to advance understanding of ICT utilization by SMMEs by checking access, ability (in terms of technological skills) and usage of ICT among some SMMEs entrepreneurs operating their businesses in an underdeveloped areas to enhance their business activities in order to utilizes the digital opportunities 21st century digital economies present. Background: In today’s world no nation or region is untouched by the forces of globalization and digital economy. One of the key pioneering forces of globalization is the advances of ICT like internet, social networks, etc. In the sphere of business, this pioneering force has also altered the way businesses and organizations communicate and interact with customers and society at large. Such alternation presents obvious opportunities for wealth creation and growth for businesses and organizations that are well-equipped to take advantages of them. But for those that are less-equipped, particularly SMMEs, globalization can easily lead to fore-closures and marginalization. It is a common knowledge that SMMEs entrepreneurs mostly rely on ICT gadgets like mobile phone, Laptops, Tablets to conduct their business activities as many of them don’t have enough capital to set up offices with necessary equipment. Therefore, using various ICT functions/programs on these ICT devices to enhance their business activities are critical to their businesses in the 21st century digital economies. Methodology: Purposeful sampling was used to approach fifty-four SMMEs entrepreneurs operating their businesses in underdeveloped areas locally called Townships in Buffalo City Metropolitan. Microsoft excel was used in the descriptive statistics. Contribution: This research will add to the growing knowledge ICT usage in SMMEs in the 21st century digital economies. Findings: The results indicate that the participating SMMEs entrepreneurs need to be educated, trained and supported in the use of the ICT applicable to enhance their business activities in order for them to take advantages of 21st century digital economies present. Recommendations for Practitioners: The agencies tasked with looking after SMMEs in South Africa needs to consider the lacked of utilisation of ICTs by SMMEs entrepreneurs operating their businesses in underdeveloped areas as one of the barrier to growing of their businesses and take necessary steps to address it. Recommendation for Researchers: Since age and gender have been proven to be key-moderating variables in many technology acceptance models. There is a need to explore in depth whether the factors of gender and age also act as barriers. Impact on Society: The research will assist stakeholders, policy makers and agencies tasked with looking after SMMEs to identify the barriers hindering SMMEs to grow and address them accordingly. Future Research: More work needs to be done to check whether gender, age of the SMMEs entrepreneurs have some effects on their attitude towards the integration of ICT into their business activities.

Modular Bridge Expansion Joints for Lacey V. Murrow Floating Bridge

1997 ◽  
Vol 1594 (1) ◽  
pp. 163-171 ◽  
Author(s):  
John A. Van Lund ◽  
Mark R. Kaczinski ◽  
Robert J. Dexter
Keyword(s):  
Fatigue Strength ◽  
Fatigue Cracking ◽  
Field Measurements ◽  
The United States ◽  
Limit States ◽  
Expansion Joints ◽  
Lake Washington ◽  
Floating Bridge ◽  
Modular Bridge Expansion Joints ◽  
Washington State Department

The Lacey V. Murrow Bridge (LVM Bridge) is a 2013-m-long floating bridge on Interstate 90 across Lake Washington in Seattle, Washington. Single-support-bar, swivel-joist modular bridge expansion joint systems are located at each end of the bridge between the shore approach spans and the floating pontoons. These joints were designed for 960 mm of longitudinal movement as well as horizontal and vertical rotations caused by wind, wave, temperature, and changes in lake level elevation. A similar joint in an adjacent floating bridge had experienced premature fatigue cracking at welded attachment details because of low fatigue strength. For the LVM Bridge the joint components were fatigue tested and designed by using fatigue limit-states loads, resulting in welded attachment details with improved fatigue strength. In addition, a stiffer center beam and reduced center-beam span lengths produced lower fatigue stress ranges. Joint movements and rotations, fatigue design methodology, results of dynamic analyses, field measurements of the dynamic response, and construction details are described. The total cost of the LVM joints was 1 percent of the final bridge cost. The Washington State Department of Transportation required a 5-year guarantee for the LVM joints. These are the largest modular bridge expansion joints in the United States to be tested and designed for fatigue.

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