Safety Evaluation of Seven of the Earliest Diverging Diamond Interchanges Installed in the United States

2016 ◽  
Vol 2583 (1) ◽  
pp. 25-33 ◽  
Author(s):  
Joseph E. Hummer ◽  
Christopher M. Cunningham ◽  
Raghavan Srinivasan ◽  
Shannon Warchol ◽  
Boris Claros ◽  
...  
Keyword(s):  
United States ◽  
Safety Evaluation ◽  
The United States ◽  
Diamond Interchanges

Lane Utilization Model Development for Diverging Diamond Interchanges

2017 ◽  
Vol 2618 (1) ◽  
pp. 27-37
Author(s):  
Chunho Yeom ◽  
Bastian J. Schroeder ◽  
Christopher Cunningham ◽  
Katy Salamati ◽  
Nagui M. Rouphail
Keyword(s):  
United States ◽  
Field Data ◽  
Model Development ◽  
The United States ◽  
Highway Capacity ◽  
Double Crossover ◽  
Highway Capacity Manual ◽  
Diamond Interchanges ◽  
Lane Utilization ◽  
Analysis Models

The diverging diamond interchange (DDI), also known as the double crossover diamond interchange, has been a successful, if unconventional, solution used in many parts of the United States ever since its first installation in Springfield, Missouri, in June 2009. One of the challenges to agencies in planning and operating DDIs is to apply to them methodologies developed for a conventional diamond interchange. The Highway Capacity Manual 2010 (HCM 2010) provides lane use analysis models for various lane configurations. However, there is no guarantee that these models will work for DDIs. For this reason, 11 DDIs were studied nationwide ( a) to examine whether the current HCM lane use models provided accurate results for DDIs and ( b) to develop new lane use models for them if the HCM models did not work. As a result of the study, unique multiregime lane utilization models were proposed, separated by the number of approach lanes and validated by field data not used in the model development.

Multijurisdictional Safety Evaluation of Red Light Cameras

2005 ◽  
Vol 1922 (1) ◽  
pp. 29-37 ◽  
Author(s):  
Bhagwant Persaud ◽  
Forrest M. Council ◽  
Craig Lyon ◽  
Kimberly Eccles ◽  
Mike Griffith
Keyword(s):  
United States ◽  
Empirical Bayes ◽  
Red Light ◽  
Spillover Effect ◽  
Safety Evaluation ◽  
Economic Cost ◽  
The United States ◽  
Companion Paper ◽  
Background Information ◽  
Outcome Variable

The use of red light camera (RLC) systems has risen dramatically in the United States in recent years. The size of the problem, the promise shown by RLC systems in other countries, and the paucity of definitive U.S. studies have motivated a multijurisdictional U.S. study. The fundamental objective of this study, which was sponsored by FHWA, was to determine the effectiveness of the RLC systems in reducing crashes at monitored intersections as well as jurisdictionwide. Phase I involved the development of a detailed experimental design that included collection of background information, establishment of study goals, selection of potential study jurisdictions, and specification of statistical methodology. In Phase 2, an empirical Bayes before-and-after study used data from seven jurisdictions across the United States, with a total of 132 treatment sites. Effects detected were consistent in direction with those found in many previous studies—a decrease in right-angle crashes and an increase in rear-end crashes—although both effects are somewhat lower than those reported in many sources. The extent to which the increase in rear-end crashes negates the benefits for right-angle crashes is unclear and points to the need for an examination of the economic cost of crashes, which is the subject of a companion paper, to aggregate the effects on rear-end, right-angle, and other crash costs. That second paper seeks to isolate all factors that would favor the installation of RLC systems by using the aggregate economic benefit as the outcome variable. There were weak indications of a spillover effect, which point to a need for a more definitive, perhaps prospective, study of this issue.

National-Level Safety Evaluation of Diverging Diamond Interchanges

2019 ◽  
Vol 2673 (7) ◽  
pp. 696-708
Author(s):  
Timothy S. Nye ◽  
Christopher M. Cunningham ◽  
Elizabeth Byrom
Keyword(s):  
Empirical Bayes ◽  
Comparison Group ◽  
National Level ◽  
Group Analysis ◽  
Safety Evaluation ◽  
The United States ◽  
Group Method ◽  
Regression To The Mean ◽  
Naive Method ◽  
Diamond Interchanges

A national-level safety evaluation of Diverging Diamond Interchanges (DDIs) in the United States was completed. This study aimed to update previous evaluations and to expand the treatment group size of previous studies to provide a more robust and reliable safety assessment of DDI deployments. For this particular treatment, it was determined that, of the observational before-and-after evaluation methodologies, the comparison group approach yields the best evaluation results. The naïve method can be influenced by outside factors that cannot be accounted for (weather, crash reporting tendencies, etc.). The empirical Bayes method is unnecessary as DDIs are installed for operational benefits, meaning that risk of selection bias and regression-to-the-mean is minimal. This study recommends a total crashes crash modification factor (CMF) of 0.633 based on the comparison group analysis of 26 DDIs in 11 states. The comparison group method was also applied to a variety of crash variables for this study. Angle, rear-end, and sideswipe crashes were found to have CMFs of 0.441, 0.549, and 1.139, respectively. Fatal-and-injury crashes provided a CMF of 0.461. Daytime and nighttime crashes provided CMFs of 0.648 and 0.638, respectively.

Safety and Management of Food Additives in the United States

2013 ◽  
Vol 781-784 ◽  
pp. 1328-1331
Author(s):  
Bo Xu
Keyword(s):  
United States ◽  
Food Industry ◽  
Food Additives ◽  
Safety Evaluation ◽  
The United States ◽  
Food Additive ◽  
Food Control ◽  
Food Management ◽  
Supervision And Management ◽  
The Government

Food safety is an important issue related to the government regulatory authorities, food industry and food consumers. And the increasing use of food additives has become a matter of public and administrative concern, so an extensive safety evaluation on food additives must be carried out and the use of the additives in food should be controlled by law. In the United States, the Congress has entrusted the FDA with the responsibility to ensure that new additives to be used in foods and the foods the consumers purchase are safe. This paper discusses the supervision and management system of food additives in the United States. The conclusion is that FDA has developed a scientifically rigorous, sound and dependable system to assure the safety of food, thus a new food additive must be approved by FDA before it can be used in food. Management of food additives in the United States is also a helpful reference for government food control agencies in other countries.

Correlative microscopy in distrubuted (client/server) computing environments: tools for catalyzing the rapid dissemination of information about the cell biology of the human prostate

1995 ◽  
Vol 53 ◽  
pp. 682-683
Author(s):  
A. Hakam ◽  
J.T. Gau ◽  
M.L. Grove ◽  
B.A. Evans ◽  
M. Shuman ◽  
...  
Keyword(s):  
United States ◽  
Cell Biology ◽  
Tissue Bank ◽  
The United States ◽  
Prostate Adenocarcinoma ◽  
Correlative Microscopy ◽  
Client Server ◽  
Critical Elements ◽  
Transplant Organ

Prostate adenocarcinoma is the most common malignant tumor of men in the United States and is the third leading cause of death in men. Despite attempts at early detection, there will be 244,000 new cases and 44,000 deaths from the disease in the United States in 1995. Therapeutic progress against this disease is hindered by an incomplete understanding of prostate epithelial cell biology, the availability of human tissues for in vitro experimentation, slow dissemination of information between prostate cancer research teams and the increasing pressure to “ stretch” research dollars at the same time staff reductions are occurring.To meet these challenges, we have used the correlative microscopy (CM) and client/server (C/S) computing to increase productivity while decreasing costs. Critical elements of our program are as follows:1) Establishing the Western Pennsylvania Genitourinary (GU) Tissue Bank which includes >100 prostates from patients with prostate adenocarcinoma as well as >20 normal prostates from transplant organ donors.

Digital image acquisition, processing, and analysis in a polymer microscopy laboratory

1994 ◽  
Vol 52 ◽  
pp. 454-455
Author(s):  
Vinod K. Berry ◽  
Xiao Zhang
Keyword(s):  
United States ◽  
Image Analysis ◽  
Digital Image ◽  
Image Acquisition ◽  
Image Transmission ◽  
The United States ◽  
Quantitative Image Analysis ◽  
Quantitative Image

In recent years it became apparent that we needed to improve productivity and efficiency in the Microscopy Laboratories in GE Plastics. It was realized that digital image acquisition, archiving, processing, analysis, and transmission over a network would be the best way to achieve this goal. Also, the capabilities of quantitative image analysis, image transmission etc. available with this approach would help us to increase our efficiency. Although the advantages of digital image acquisition, processing, archiving, etc. have been described and are being practiced in many SEM, laboratories, they have not been generally applied in microscopy laboratories (TEM, Optical, SEM and others) and impact on increased productivity has not been yet exploited as well.In order to attain our objective we have acquired a SEMICAPS imaging workstation for each of the GE Plastic sites in the United States. We have integrated the workstation with the microscopes and their peripherals as shown in Figure 1.

Silence of the Land: On the Historical Irrelevance of Territory to Congressional Districting and Political Representation in the United States

2001 ◽  
Vol 15 (01) ◽  
pp. 53-87 ◽  
Author(s):  
Andrew Rehfeld
Keyword(s):  
United States ◽  
House Of Representatives ◽  
Political Representation ◽  
The United States ◽  
Representative Government ◽  
Congressional District ◽  
Congressional Districts ◽  
Communities Of Interest

Every ten years, the United States “constructs” itself politically. On a decennial basis, U.S. Congressional districts are quite literally drawn, physically constructing political representation in the House of Representatives on the basis of where one lives. Why does the United States do it this way? What justifies domicile as the sole criteria of constituency construction? These are the questions raised in this article. Contrary to many contemporary understandings of representation at the founding, I argue that there were no principled reasons for using domicile as the method of organizing for political representation. Even in 1787, the Congressional district was expected to be far too large to map onto existing communities of interest. Instead, territory should be understood as forming a habit of mind for the founders, even while it was necessary to achieve other democratic aims of representative government.

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