The American Society for Testing and Materials (ASTM) is an independent organization devoted to the development of standards.

American Society for Testing and Materials

The Environmental Protection Agency (EPA) provides access to information on a variety of topics related to the environment and strives to inform citizens of health risks. The EPA also has an extensive library network that consists of 26 libraries throughout the United States, which provide access to a plethora of information to EPA employees, scientists, and researchers. The EPA implemented a reorganization project to digitize their materials so they would be more accessible to a wider range of users, but this plan was drastically accelerated when the EPA was threatened with a budget cut. It chose to close and reduce the hours and services of some of their libraries. As a result, the agency was accused of denying users the “right to know” by making information unavailable, not providing an adequate strategic plan, and discarding vital materials. This case study explores the background of the digitization project, the practices implemented, and the critiques of the project.

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The Environmental Protection Agency

Artificial neural networks (ANNs) constitute a class of flexible nonlinear models designed to mimic biological neural systems. In this entry, we introduce ANN using familiar econometric terminology and provide an overview of ANN modeling approach and its implementation methods. † Correspondence: Chung-Ming Kuan, Institute of Economics, Academia Sinica, 128 Academia Road, Sec. 2, Taipei 115, Taiwan; ckuan@econ.sinica.edu.tw. †† I would like to express my sincere gratitude to the editor, Professor Steven Durlauf, for his patience and constructive comments on early drafts of this entry. I also thank Shih-Hsun Hsu and Yu-Lieh Huang for very helpful suggestions. The remaining errors are all mine.

Artificial neural networks

Highway Capacity Manual改訂の動向--テイラ-教授の講演より

Dynamics of structures

Ground-penetrating radar (GPR) has shown great potential for asphalt concrete density prediction used in quality control and quality assurance. One challenge of continuous GPR measurements is that ...

Signal Stability and the Height-Correction Method for Ground-Penetrating Radar In Situ Asphalt Concrete Density Prediction:

The use of biaxial geogrids for enhancing the performance of sub-ballast and ballast layers—previous experience and research

This study examined and developed feasible chemical methods for the corrosion protection of reinforcing steel in concrete bridges. A broad spectrum of chemicals were evaluated: corrosion inhibitors, chloride scavengers, and polyaphrons. Inhibitors were evaluated and recommendations were made. Reinforced concrete specimens were cast and subjected to repeated exposure to sodium chloride solution and evaluated to investigate the inhibitors effectiveness after removing contaminated concrete. Corrosion progress was monitored. Polyaphrons were investigated as a possible corrosion preventor/reducer inhibitor. Based on results, polyaphrons are not recommended as a practical concrete bridge treatment.

Concrete bridge protection and rehabilitation: chemical and physical techniques. feasibility studies of new rehabilitation techniques

Use of sustainable and cost-effective pavement overlays as a rehabilitation technique has been emphasized for several years as oil prices continue their instability in the United States. Since the 1980s, significant advances have been introduced in asphalt pavements regarding material selection, mix design, and construction technology that improve pavement performance. Some of these improvements require the use of a highly modified asphalt binder and expensive high-quality aggregates to achieve the desired performance. This study developed four potentially cost-effective asphalt mixtures and efficient cross sections for asphalt wearing surfaces. The newly developed asphalt mixes incorporated locally available aggregates, special binder additives such as fibers, innovative surfacing technologies, or all of these techniques. The cost-effectiveness of the newly developed asphalt mixtures is presented, and the improved performance is considered. Deterministic and probabilistic life-cycle cost analysis was per...

Engineering Cost-Benefit Analysis of Thin, Durable Asphalt Overlays

The bituminous sealants used in the preventive maintenance of pavements sometimes deform (track) under the action of passing vehicles. In summer, this is the prevalent mode of sealant failure. To assess the propensity of a sealant to deform in summer, a standard flow test is used, but the imprecision in the results has prevented any correlation with field performance. Two methods were evaluated in an attempt to find an alternative means of assessing deformation. The first method relied on the use of the French rut tester, and the second method relied on the use of a Taber abraser. The first method was found to be inappropriate to test sealants because of its severity, but the second method proved promising. The Taber abraser allowed for the measurement of sealant displacement at various temperatures and for distinguishing the deformation propensity of sealants.Key words: pavements, roadways, maintenance, sealants, sealing, specification, testing, performance.

/pdf/rapid-assessment-of-the-tracking-resistance-of-bituminous-1f0aaa3pgw.pdf

Imad L. Al-Qadi

Papers

Signal Stability and the Height-Correction Method for Ground-Penetrating Radar In Situ Asphalt Concrete Density Prediction:

The use of biaxial geogrids for enhancing the performance of sub-ballast and ballast layers—previous experience and research

Concrete bridge protection and rehabilitation: chemical and physical techniques. feasibility studies of new rehabilitation techniques

Engineering Cost-Benefit Analysis of Thin, Durable Asphalt Overlays

Rapid assessment of the tracking resistance of bituminous crack sealants