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.

/pdf/the-environmental-protection-agency-3gx4opzrjm.pdf

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

16. Abstract This study investigated the effect of high asphalt binder replacement for a low N-design asphalt mixture including RAP and RAS on performance indicators such as permanent deformation, fracture, fatigue potentials, and stiffness, was studied. An experimental program included complex modulus, fracture, overlay reflective cracking resistance, wheel track permanent deformations, and push-pull fatigue tests. The asphalt binder replacement, combinations of RAS and RAP asphalt binder, levels in the mix were in a range of 43 to 64%. According to the results obtained from the experimental program, permanent deformation resistance of the mixtures was improved in the presence of RAS. Fracture tests at low temperature did not reveal any significant difference between the specimens prepared at varying percentages of asphalt binder replacement. Fatigue potential of mixtures increased with increasing RAS content and asphalt binder replacement. The specimens prepared with 2.5% RAS and PG 4634 showed the best fatigue performance. The impact of asphalt binder bumping was highlighted by the results of all tests. The improvement in fatigue life and fracture energy was noticeable when the asphalt binder type was changed from PG 58-28 to PG 46-34 at the highest asphalt binder replacement level. The results showed that complex modulus test results can provide crucial information about the mix viscoelastic properties such as relaxation potential and long-term stiffness that can be used, along with fracture tests, to evaluate mix brittleness at relatively high asphalt binder replacement levels.

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Laboratory Evaluation of High Asphalt Binder Replacement with Recycled Asphalt Shingles (RAS) for a Low N-Design Asphalt Mixture

The transportation sector contributes up to 27% of the total greenhouse gas (GHG) emissions in the United States; on-road transportation is responsible for 84% of the entire sector, implyin...

Impact of Pavement Roughness and Deflection on Fuel Consumption Using Energy Dissipation

With a large portion of vehicles still relying on the combustion of petroleum, the transportation sector was reported to be responsible for 27% of the greenhouse gas emissions in the United...

Stochastic Analysis of Energy Dissipation of a Half-Car Model on Nondeformable Rough Pavement

Influence of mix design parameters on asphalt concrete aging rate using I-FIT specimens

Ground-penetrating radar (GPR) is a nondestructive investigation tool that is usually used in flexible pavement evaluation to estimate the thicknesses of the various layers composing the pavement. GPR is also used in flexible pavements to detect subsurface distresses, such as moisture accumulation and air voids. For rigid pavements and bridge decks, GPR is used to measure the thickness of the concrete slab and detect the location of reinforcing bars (rebar). Rebar detection is typically achieved, in this case, when an experienced operator finds the rebar's classic parabolic signature in the GPR data. This paper presents image-processing techniques that can be used to detect the rebar parabolic signature automatically in GPR data collected from rigid pavements with a high-frequency ground-coupled antenna. After detection of the rebar, the reflected parabolic shape is fit to a theoretical reflection model to estimate the pavement's dielectric constant and the rebar depth. The algorithms were validated on GP...

Imad L. Al-Qadi

Papers

Laboratory Evaluation of High Asphalt Binder Replacement with Recycled Asphalt Shingles (RAS) for a Low N-Design Asphalt Mixture

Impact of Pavement Roughness and Deflection on Fuel Consumption Using Energy Dissipation

Stochastic Analysis of Energy Dissipation of a Half-Car Model on Nondeformable Rough Pavement

Influence of mix design parameters on asphalt concrete aging rate using I-FIT specimens

Part 4: Portland Cement Concrete Pavement: Measuring Rebar Cover Depth in Rigid Pavements with Ground-Penetrating Radar