scholarly journals Assignment of Freight Truck Shipment on the U.S. Highway Network

2021 ◽  
Vol 13 (11) ◽  
pp. 6369
Author(s):  
Taesung Hwang
Keyword(s):  
United States ◽  
Traffic Congestion ◽  
The United States ◽  
User Equilibrium ◽  
Highway Infrastructure ◽  
Geographical Regions ◽  
Highway Network ◽  
Congestion Effect ◽  
Link Cost ◽  
Increasing Demand

With the ever-increasing demand for freight movements, nationwide freight shipments between geographical regions by freight trucks need to be investigated since they comprise the largest share of total freight movements in the United States. To this end, the procedures for freight truck shipment demand network assignment on the entire U.S. highway network considering congestion effect are discussed, and the results are explained in detail, with visual illustrations. A fundamental traffic assignment model with a convex combinations algorithm is proposed to solve the nationwide freight truck shipment assignment problem under the user equilibrium principle. A link cost function is modified, considering the traffic volume that already exists on U.S. highways. A case study is conducted using big data including the entire U.S. highway network and freight shipment information in 2007. Total and average freight shipment costs for both truck and rail transportation for a specific origin–destination pair in the database are computed to compare the characteristics of these two major freight transportation modes in the United States. Application of the proposed model could be possible to address many other related problems, such as improvement of highway infrastructure, and reductions in traffic congestion and vehicle emissions.

scholarly journals Prevalence of single and coinfections of human pathogens in Ixodes ticks from five geographical regions in the United States, 2013–2019

2021 ◽  
Vol 12 (2) ◽  
pp. 101637
Author(s):  
Aine Lehane ◽  
Sarah E. Maes ◽  
Christine B. Graham ◽  
Emma Jones ◽  
Mark Delorey ◽  
...  
Keyword(s):  
United States ◽  
The United States ◽  
Human Pathogens ◽  
Geographical Regions ◽  
Ixodes Ticks

scholarly journals Underneath Kyoto: Emerging Subnational Government Initiatives and Incipient Issue-Bundling Opportunities in China and the United States

2008 ◽  
Vol 8 (1) ◽  
pp. 53-77 ◽  
Author(s):  
Peter H. Koehn
Keyword(s):  
United States ◽  
Stress Reduction ◽  
Traffic Congestion ◽  
Local Level ◽  
National Level ◽  
Ghg Emissions ◽  
The United States ◽  
Healthy Human ◽  
Republic Of China ◽  
Stabilization Policies

At present, progress in mitigating global GHG emissions is impeded by political stalemate at the national level in the United States and the People's Republic of China. Through the conceptual lenses of multilevel governance and framing politics, the article analyzes emerging policy initiatives among subnational governments in both countries. Effective subnational emission-mitigating action requires framing climatic-stabilization policies in terms of local co-benefits associated with environmental protection, health promotion, and economic advantage. In an impressive group of US states and cities, and increasingly at the local level in China, public concerns about air pollution, consumption and waste management, traffic congestion, health threats, the ability to attract tourists, and/or diminishing resources are legitimizing policy developments that carry the co-benefit of controlling GHG emissions. A co-benefits framing strategy that links individual and community concerns for morbidity, mortality, stress reduction, and healthy human development for all with GHG-emission limitation/reduction is especially likely to resonate powerfully at the subnational level throughout China and the United States.

American Agriculture, 1800–1862

2018 ◽  
Author(s):  
Richard Lyman Bushman
Keyword(s):  
United States ◽  
World War Ii ◽  
The United States ◽  
World War ◽  
Urban Populations ◽  
Farm Life ◽  
Market Production ◽  
Increasing Demand ◽  
American Agriculture ◽  
Improved Methods

After 1800, the primary market for agricultural products shifted from overseas ports to cities in the United States. Growing urban populations created an ever-increasing demand, not only for standard products like breadstuffs and meat, but for new ones like pears and brooms. To take advantage of this opportunity, farmers increased their efficiency by employing machinery and cropping their fields continuously rather than letting them go to long fallow. This created a need for fertilizers to restore the soil and permanent fences for fields that remained in use. Under the influence of city values, farmers spent the returns from their heightened sales on refinements such as carpets and curtains to counter the charge of being rural rubes. Despite the adoption of improved methods to increase market production, farmers still practiced self-provisioning as far as possible. They made and grew everything they could for themselves even while their needs for urban goods increased. Not until World War II did farmers give up the practice of living off their farms. Since then, the number of small farms has steadily diminished and the farm population has shrunk to less than 2% of the population. Still farmers value the integrity of the farm life and want their children to participate.

scholarly journals An Analysis of Equity Among Policy Solutions for Traffic Congestion

2020 ◽  
Vol 27 ◽  
Author(s):  
Ethan Steakley
Keyword(s):  
United States ◽  
Traffic Congestion ◽  
Road Pricing ◽  
The United States ◽  
Vertical Equity ◽  
Flat Tax ◽  
Tax Rate ◽  
Evaluative Criteria ◽  
Future Policy ◽  
Policy Solutions

The emergence of ride-hailing in the United States has brought forth new issues for its cities, particularly a large influx of traffic congestion. Today, several cities have introduced distinct ideas to solve congestion issues while debating their implications for equity. This paper examines the equity implications of traffic congestion in America'•s cities by comparing a flat tax rate on ride-hailing to various road pricing mechanisms using specific evaluative criteria, including transportation access and vertical equity. This paper begins with an overview of ride-hailing in the United States and the congestion problem it poses for cities, then reviews the literature around congestion and equity, describes and assesses the equity of a flat tax rate and road pricing, and ends with broad implications resourced from the literature for future policy.

Challenges Facing Contemporary Community Colleges

2019 ◽  
pp. 186-200
Author(s):  
Shah S. Ardalan
Keyword(s):  
Higher Education ◽  
United States ◽  
Community Colleges ◽  
Open Access ◽  
Undergraduate Students ◽  
The United States ◽  
Workforce Training ◽  
Socioeconomically Disadvantaged ◽  
Increasing Demand ◽  
Student Completion

For over a century, American community colleges have delivered on their mission of open access and now educate about half of all undergraduate students in the United States. Recognized as primary providers of higher education and workforce training, especially to non-traditional and socioeconomically disadvantaged students, community colleges serve as transformative engines of prosperity and democratization of education. Contemporary community colleges face many challenges. Mainly, while community colleges are persistently underfunded, their leaders are under ever-increasing demand to improve student completion.

Epidemiology of Escherichia coli O157 in Feedlot Cattle

1997 ◽  
Vol 60 (5) ◽  
pp. 462-465 ◽  
Author(s):  
DALE D. HANCOCK ◽  
DANIEL H. RICE ◽  
LEE ANN THOMAS ◽  
DAVID A. DARGATZ ◽  
THOMAS E. BESSER
Keyword(s):  
United States ◽  
Escherichia Coli ◽  
The United States ◽  
Feedlot Cattle ◽  
Escherichia Coli O157 ◽  
Fecal Samples ◽  
E Coli ◽  
Geographical Regions ◽  
Flagellar Antigen ◽  
Low Prevalence

Fecal samples from cattle in 100 feedlots in 13 states were bacteriologically cultured for Escherichia coli O157 that did not ferment sorbitol, lacked beta-glucuronidase, and possessed genes coding for Shiga-like toxin. In each feedlot 30 fresh fecal-pat samples were collected from each of four pens: with the cattle shortest on feed, with cattle longest on feed, and with cattle in two randomly selected pens. E. coli O157 was isolated from 210 (1.8%) of 11,881 fecal samples. One or more samples were positive for E. coli O157 in 63 of the 100 feedlots tested. E. coli O157 was found at roughly equal prevalence in all the geographical regions sampled. The prevalence of E. coli O157 in the pens with cattle shortest on feed was approximately threefold higher than for randomly selected and longest on feed pens. Of the E. coli O157 isolates found in this study, 89.52% expressed the H7 flagellar antigen. E. coli O157 was found to be widely distributed among feedlot cattle, but at a low prevalence, in the United States.

scholarly journals Genetic Diversity of Sclerotinia homoeocarpa Isolates from Turfgrasses from Various Regions in North America

Plant Disease ◽  
2004 ◽  
Vol 88 (11) ◽  
pp. 1269-1276 ◽  
Author(s):  
G. Viji ◽  
W. Uddin ◽  
N. R. O'Neill ◽  
S. Mischke ◽  
J. A. Saunders
Keyword(s):  
United States ◽  
Genetic Diversity ◽  
Creeping Bentgrass ◽  
The United States ◽  
Vegetative Compatibility ◽  
Major Group ◽  
Golf Courses ◽  
Sclerotinia Homoeocarpa ◽  
Dollar Spot ◽  
Geographical Regions

Sixty-seven isolates of Sclerotinia homoeocarpa, causing dollar spot disease in creeping bentgrass, annual bluegrass, Bermudagrass, and perennial ryegrass turf, collected from 23 golf courses in various geographical regions of the United States and Canada between 1972 and 2001, were characterized by vegetative compatibility, genetic diversity, and pathogenicity. Eleven vegetative compatibility groups (VCGs A to K) were identified among the isolates tested in this study, and five of them (VCGs G to K) were new. VCG B was the most predominant group, typifying 33 isolates (51%) tested. S. homoeocarpa isolates collected from golf courses in Pennsylvania belonged to seven VCGs (A, B, E, F, G, I, and K), whereas three groups were observed in those collected from New York (B, E, and G) and New Jersey (E, H, and I). Two isolates, one each from Pennsylvania and Canada, were incompatible when paired with the tester isolates in all possible combinations, and did not fall into any known VCG. An isolate collected from Canada was compatible with tester isolates from two VCGs (C and D). Genetic analyses using amplified fragment length polymorphism (AFLP) showed the presence of two genetically distinct groups, designated as major group and the minor group. The major group included 36 isolates collected from various golf courses in the United States and Canada. Two isolates collected from bermudagrass in Florida formed a separate cluster, the minor group. Isolates that belonged to the major group were further divided into two subgroups (1 and 2). Subgroup 1 consisted of all the isolates that belonged to VCGs A, E, G, H, and I. Three of the four isolates that belonged to VCG K also were clustered with isolates of subgroup 1. Subgroup 2 consisted of all the isolates from VCG B, and one each from VCGs F and K. Pathogenicity assays on Penncross creeping bentgrass showed significant differences (P = 0.05) in virulence among the isolates. Overall, a relationship between virulence and VCGs was observed, in which certain virulence groups corresponded to specific VCGs; however, such a relationship was not observed between virulence and AFLPs. Close similarity among isolates of S. homoeocarpa collected from different locations in the United States and Canada suggests that isolates of the same genotype could be involved in outbreaks of dollar spot epidemics at multiple locations.

scholarly journals The North American Lightning Detection Network (NALDN)—Analysis of Flash Data: 2001–09

2011 ◽  
Vol 139 (5) ◽  
pp. 1305-1322 ◽  
Author(s):  
Richard E. Orville ◽  
Gary R. Huffines ◽  
William R. Burrows ◽  
Kenneth L. Cummins
Keyword(s):  
United States ◽  
North America ◽  
North American ◽  
The United States ◽  
The North ◽  
Lightning Detection ◽  
Geographical Regions ◽  
Positive Peak ◽  
The U.S ◽  
Cg Lightning

Cloud-to-ground (CG) lightning data have been analyzed for the years 2001–09 for North America, which includes Alaska, Canada, and the lower 48 U.S. states. Flashes recorded within the North American Lightning Detection Network (NALDN) are examined. No corrections for detection efficiency variability are made over the 9 yr of the dataset or over the large geographical area comprising North America. There were network changes in the NALDN during the 9 yr, but these changes have not been corrected for nor have the recorded data been altered in any way with the exception that all positive lightning reports with peak currents less than 15 kA have been deleted. Thus, the reader should be aware that secular changes are not just climatological in nature. All data were analyzed with a spatial resolution of 20 km. The analyses presented in this work provide a synoptic view of the interannual variability of lightning observations in North America, including the impacts of physical changes in the network during the 9 yr of study. These data complement and extend previous analyses that evaluate the U.S. NLDN during periods of upgrade. The total (negative and positive) flashes for ground flash density, the percentage of positive lightning, and the positive flash density have been analyzed. Furthermore, the negative and positive first stroke peak currents and the flash multiplicity have been examined. The highest flash densities in Canada are along the U.S.–Canadian border (1–2 flashes per square kilometer) and in the United States along the Gulf of Mexico coast from Texas through Florida (exceeding 14 flashes per square kilometer in Florida). The Gulf Stream is “outlined” by higher flash densities off the east coast of the United States. Maximum annual positive flash densities in Canada range primarily from 0.01 to 0.3 flashes per square kilometer, and in the United States to over 0.5 flashes per square kilometer in the Midwest and in the states of Louisiana and Mississippi. The annual percentage of positive lightning to ground varies from less than 2% over Florida to values exceeding 25% off the West Coast, Alaska, and the Yukon. A localized maximum in the percentage of positive lightning in the NALDN occurs in Manitoba and western Ontario, just north of North Dakota and Minnesota. When averaged over North America, first stroke negative median peak currents range from 19.8 kA in 2001 to 16.0 kA in 2009 and for all years, average 16.1 kA. First stroke positive median peak currents range from a high of 29.0 kA in 2008 and 2009 to a low of 23.3 kA in 2003 with a median of 25.7 kA for all years. There is a relatively sharp transition from low to high median negative peak currents along the Gulf and Atlantic coasts of the United States. No sharp transitions are observed for the median positive peak currents. Relatively lower positive peak currents occur throughout the southeastern United States. The highest values of mean negative multiplicity exceed 3.0 strokes per flash in the NALDN with some variation over the 9 yr. Lower values of mean negative multiplicity occur in the western United States. Positive flash mean multiplicity is slightly higher than 1.1, with the highest values of 1.7 observed in the southwestern states. As has been noted in prior research, CG lightning has significant variations from storm to storm as well as between geographical regions and/or seasons and, consequently, a single distribution for any lightning parameter, such as multiplicity or peak current, may not be sufficient to represent or describe the parameter.

A Regional Difference in Perception of the Tritone Paradox within the United States

1994 ◽  
Vol 12 (2) ◽  
pp. 213-225 ◽  
Author(s):  
Frank Ragozzine ◽  
Diana Deutsch
Keyword(s):  
United States ◽  
Regional Differences ◽  
Regional Difference ◽  
The United States ◽  
Striking Difference ◽  
The South ◽  
Geographical Regions ◽  
Significant Difference ◽  
Tritone Paradox ◽  
English Group

A previous study (Deutsch, 1991) demonstrated a striking difference in perception of the tritone paradox between subjects who had grown up in two different geographical regions. Specifically, a group of subjects who had grown up in California were compared with a group who had grown up in the South of England. When the Californian group tended to hear the pattern as ascending, the English group tended to hear it as descending, and vice versa. This raises the question of whether regional differences also exist within the United States in the way this pattern is perceived. The present study examined the percepts of subjects who had grown up in Mahoning and/or Trumbull counties in Ohio. Two groups were compared: those whose parents had also grown up in this area and those for whom this was not the case. A highly significant difference between these two groups of subjects was obtained, with those in the latter group producing a distribution of percepts similar to that found among Californians and those in the former group producing a different distribution. From this and other analyses of the data, it is concluded that regional differences in perception of the tritone paradox do indeed exist within the United States and that there is in addition an effect of familial background.

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