Refinement of New-Generation Open-Graded Friction Course Mix Design

2003 ◽  
Vol 1832 (1) ◽  
pp. 78-85 ◽  
Author(s):  
Donald E. Watson ◽  
Kathryn Ann Moore ◽  
Kevin Williams ◽  
L. Allen Cooley
Keyword(s):  
United States ◽  
Design Procedure ◽  
The United States ◽  
Mix Design ◽  
Superpave Gyratory Compactor ◽  
Open Graded Friction Course ◽  
Compactive Effort ◽  
And Performance ◽  
New Generation ◽  
Air Void

Open-graded friction course (OGFC) has been used in the United States for more than 50 years. In 2000, National Center for Asphalt Technology (NCAT) research led to a recommended mix design procedure for a new-generation OGFC, but the work involved only one aggregate source. Therefore, NCAT is in the process of refining this design procedure to ensure that it is applicable to other aggregate types used in surface mixes throughout the United States. The objectives of NCAT's current research are to refine and field validate the new-generation OGFC mix design procedure. This work has led to several experiments. Several objectives have been identified that need to be addressed. Superpave® technology and use of the Superpave gyratory compactor (SGC) need to be incorporated into the mix design procedure. The Cantabro test for durability and resistance to stone loss needs to be adapted to SGC-prepared specimens and performance parameters established. The asphalt draindown test (AASHTO T 305-97), which was developed for stone-matrix asphalt mixtures, also needs to be evaluated for applicability to OGFC mixtures. In addition, a method for effectively evaluating air void criteria needs to be investigated. On the basis of the research conducted in this study, 50 gyrations of the SGC was selected as the design compactive effort during mix design. Also, the use of SGC-prepared samples during the Cantabro test appears to be a reasonable alternative to use of Marshall-compacted samples.

scholarly journals Co-Occurrence of 35 Mycotoxins: A Seven-Year Survey of Corn Grain and Corn Silage in the United States

Toxins ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 516
Author(s):  
Alexandra C. Weaver ◽  
Daniel M. Weaver ◽  
Nicholas Adams ◽  
Alexandros Yiannikouris
Keyword(s):  
United States ◽  
Animal Health ◽  
Fusaric Acid ◽  
Fumonisin B1 ◽  
The United States ◽  
Ultra Performance Liquid Chromatography ◽  
Liquid Chromatography Tandem Mass ◽  
And Performance ◽  
The Impact ◽  
Corn Grain

Mycotoxins contaminate crops worldwide and play a role in animal health and performance. Multiple mycotoxins may co-occur which may increase the impact on the animal. To assess the multiple mycotoxin profile of corn (Zea mays), we conducted a 7-year survey of new crop corn grain and silage in the United States. A total of 711 grain and 1117 silage samples were collected between 2013 and 2019 and analyzed for the simultaneous presence of 35 mycotoxins using ultra-performance liquid chromatography–tandem mass spectrometry. The measured mean number of mycotoxins per sample were 4.8 (grain) and 5.2 (silage), ranging from 0 to 13. Fusaric acid (FA) was most frequently detected in 78.1 and 93.8% of grains and silages, respectively, followed by deoxynivalenol (DON) in 75.7 and 88.2% of samples. Fumonisin B1 (FB1), fumonisin B2 and 15-acetyl-deoxynivalenol (15ADON) followed. The greatest (p < 0.05) co-occurrence was between FA and DON in 59.1% of grains and 82.7% of silages, followed by FA with FB1, DON with 15ADON, and FA with 15ADON. Although many samples had lower mycotoxin concentrations, 1.6% (grain) and 7.9% (silage) of tested samples had DON ≥ 5000 µg/kg. Fumonisins were detected ≥ 10,000 µg/kg in 9.6 and 3.9% of grain and silage samples, respectively. Concentrations in grain varied by year for eight mycotoxin groups (p < 0.05), while all 10 groups showed yearly variations in silage. Our survey suggest that multiple mycotoxins frequently co-occur in corn grain and silage in the Unites States, and some of the more prevalent mycotoxins are those that may not be routinely analyzed (i.e., FA and 15ADON). Assessment of multiple mycotoxins should be considered when developing management programs.

A comparative study of piano performance programs at university-level institutions in China and the United States: From current faculty members’ and students’ perspectives

2021 ◽  
pp. 025576142110657
Author(s):  
Yuan Jiang
Keyword(s):  
United States ◽  
The United States ◽  
Faculty Members ◽  
Prospective Students ◽  
Piano Performance ◽  
Positive Attitudes ◽  
Challenging Tasks ◽  
Applied Lessons ◽  
University Level ◽  
And Performance

This study investigated the perceptions of piano performance programs in higher education from current collegiate students and faculty members’ perspectives in China and the United States. Participants were from representative university-level institutions in the U.S. ( n = 41) and China ( n = 130). They were sent a questionnaire concerning (a) the factors that motivate students to pursue a piano performance degree, (b) the most important educational practices in their programs, (c) the most challenging tasks the students encounter, (d) students’ career goal, and (e) faculty members’ suggestions for prospective students and opinions on improving the piano performance programs. A summary of students and faculty members’ perceptions were outlined and the comparison between the two countries were explored. It is encouraging that not only students gave careful attention toward the applied lessons and performance opportunities in their studies, but also that a large percentage of the students believed they received excellent advice regarding practice strategies and artistry in their applied lessons in both countries. Most of the faculty participants in both countries expressed positive attitudes regarding the piano performance programs in their universities. By providing statistically significant data, this study provides a comprehensive vision for institutions to continue establishing piano programs.

An Empirical Review of the Design and Performance of Icebreakers

1989 ◽  
Vol 26 (02) ◽  
pp. 145-159
Author(s):  
R. A. Dick ◽  
J. E. Laframboise
Keyword(s):  
United States ◽  
Soviet Union ◽  
State Of The Art ◽  
The United States ◽  
West Germany ◽  
The United Kingdom ◽  
The Soviet Union ◽  
And Performance ◽  
Ship Performance ◽  
Selection Of

This paper utilizes available data on existing icebreaking ships to compile a review of the design features that influence ship performance. The data were extracted from a recently completed review of the state of the art of Arctic ship technology and include icebreaking ships from Argentina, Canada, Denmark, Finland, Japan, Sweden, the United Kingdom, the Soviet Union, the United States, and West Germany. It is the aim of this paper to offer guidance in the initial stages of icebreaker design and thereby give confidence to the designer in the selection of dimensions, hull shape and propulsion.

Conclusion

2015 ◽  
Author(s):  
Udi Greenberg
Keyword(s):  
United States ◽  
The United States ◽  
West Germany ◽  
Student Movements ◽  
Left Wing ◽  
State Institutions ◽  
Small Organizations ◽  
New Vision ◽  
The 1960S ◽  
New Generation

This chapter considers the new vision of democracy ushered in by the generation of the 1960s. Unlike the architects of the postwar order, left-wing students challenged, rather than celebrated, the legitimacy of elected institutions and party politics. Parliaments were merely stages for oligarchies, tools for self-perpetuating elites. In both West Germany and the United States, students claimed that state institutions inevitably reinforced rigid hierarchies and oppressive norms. A “true” democracy could not be built by state agencies. Rather, it would emerge from “autonomy,” from small organizations, student movements, NGOs, and, later, human rights organizations. When the frustration and anger of this new generation exploded in protest in the late 1960s, German émigrés were among its main targets. Student journals and pamphlets frequently attacked and ridiculed the leading thinkers of the older generation. Such criticism was especially ferocious in West Germany, where returning émigrés came to represent Cold War ties with an amoral and depraved United States.

Bombing Flies

2018 ◽  
pp. 223-246
Author(s):  
Clapperton Chakanetsa Mavhunga
Keyword(s):  
United States ◽  
South Africa ◽  
Organochlorine Pesticides ◽  
Large Scale ◽  
The United States ◽  
Ease Of Use ◽  
Technical Aspects ◽  
Aerial Spraying ◽  
And Performance ◽  
Ground Spraying

This chapter explores the use of aircraft to spray organochlorine pesticides (OCPs). It begins by tracing the origins of the practice in KwaZulu, South Africa, where ndege were adopted for pesticide spraying because of their ease of use, capacity for large-scale coverage, very few personnel required, and capability to reach mpukane habitats otherwise inaccessible by ground spraying. The second section examines the technical aspects of aerial spraying as an example of the extension of methods designed in the United States for agricultural or military purposes to deal with zvipukanana and with conditions for which they were not originally designed. In the final sections, the deployment and performance of first fixed-wing aircraft and then helicopters are closely examined.

“Every Brother on a Rooftop Can Quote Fanon”

2017 ◽  
Author(s):  
Sean L. Malloy
Keyword(s):  
United States ◽  
Black Americans ◽  
The United States ◽  
Malcolm X ◽  
Amiri Baraka ◽  
The Third ◽  
The 1960S ◽  
The Third World ◽  
Lorraine Hansberry ◽  
New Generation

This chapter examines the intersection of the domestic and international developments that shaped the creation of black-led movements that looked beyond the borders of the United States for support and legitimacy in the 1960s. By the mid-1960s, the notion that black Americans should seek solidarity with the Third World rather than looking to Washington for help had attracted advocates ranging from Williams to Malcolm X, Lorraine Hansberry, Amiri Baraka, Vicki Garvin, Harold Cruse, and groups such as the Revolutionary Action Movement (RAM). The successes—and failures—of these pioneering figures helped pave the way for a new generation of activists, including key figures in the birth and development of the Black Panther Party.

National regeneration and the education of the Latin American elites

2018 ◽  
pp. 86-115
Author(s):  
Michela Coletta
Keyword(s):  
United States ◽  
Latin American ◽  
Direct Contact ◽  
The United States ◽  
National Character ◽  
Spanish American ◽  
Anglo Saxon ◽  
Spatial Direction ◽  
New Generation ◽  
Cultural Connotations

Given the essentially cultural connotations of the notion of ‘Latin race’, education was widely perceived as a key tool for bringing about a process of national and regional regeneration. ‘The problem of the race’ was closely linked to ‘the problem of education’. What characterised the debate on education in all three countries was a deep concern with the need for a regeneration of the national character. This chapter explores the debates around Latin and Anglo-Saxon education models and the ways in which major contemporary theories of education were incorporated. Intellectual exchanges with the Spanish ‘regeneracionistas’ were key in the case of the pedagogical strand of Krausismo in the River Plate and especially in Uruguay. What approach to education best suited the Spanish American nations? Was ‘Latin’ education the best model to adopt? The ‘spatial’ direction of these exchanges is in itself revealing of the different national tendencies: while the Chileans ostensibly and increasingly looked towards the United States, the River Plate was largely part of a revival of Krausismo through direct contact with a new generation of Spanish krausistas. 

Sign in / Sign up

Export Citation Format

Share Document