831 research outputs found
Teaching Ability and Sexuality
The author discusses reconciling their sexual identity and their chosen profession
Delineation of Horizontal Curves
The objective of this study was to investigate the ability of various traffic control measures to delineate horizontal curves so drivers would perceive the curve and slow to an appropriate speed and then be provided guidance through the curve. Pavement delineation (raised pavement markers, transverse stripes, or rumble strips) and shoulder delineation (post delineators and chevron signs) were used. A laboratory test found that a post delineator configuration in which the distance from the post to the pavement edge and the post spacing remained constant while the height of the delineator on the post increased made a curve appear sharper than other delineator configurations. The delineation treatments did not dramatically decrease speeds at the point of curve, but encroachments decreased substantially and the severity of the encroachments was reduced at locations that originally had a high proportion of moderate or severe encroachments. Pavement delineation had more of an affect than shoulder delineation. Also, chevron signs were more effective than post delineators
Effectiveness of Traffic Noise Barrier on I 471 in Campbell County, Kentucky (Interim Report)
The objective of this study is-to evaluate the effectiveness of the traffic noise barrier on I 471 in Campbell County, Kentucky. Since the barrier construction coincided with construction of I 471, it was necessary to predict noise levels that would exist if no barrier were present by utilizing the FHWA STAMINA 2.0 computer model. This was compared to actual noise level measurements at the barrier site in order to determine the barrier insertion loss.
After calibration of the STAMINA 2.0 model, initial field measurements were taken at receiver locations throughout the barrier site. The average insertion loss in Leq was found to be 7.0 dBA, ranging from 3.5 dBA to 13.0 dBA. The average insertion loss in L10 was found to be 8.2 dBA, ranging from 5.0 dBA to 14.3 dBA.
A questionnaire to be used in a community perception survey was developed. The survery will be distributed and the results summarized in the final report
Development of Accident Reduction Factors
In order to use the cost-optimization procedure of dynamic programming to rank safety improvements, improvement costs and benefits must be input. The benefits are in terms of accident reductions resulting from specific safety improvements. In this study a comprehensive list of accident reduction factors were developed to use in the cost-optimization program. The development of the list of reduction factors was based mainly on a review of literature and survey of states, with limited input from a before-and-after accident analysis
Effectiveness of Traffic Noise Barrier on I 471 in Campbell County, Kentucky
The objective of this study was to evaluate the effectiveness of the traffic noise barrier on I 471 in Campbell County, Kentucky. Since the barrier coincided with construction of I 471, it was necessary to predict noise levels that would exist if no barrier were present utilizing the FHWA STAMINA 2.0 computer model. This was compared to actual noise level measurements at the barrier site to determine the barrier insertion loss.
After calibration of the STAMINA 2.0 model, noise measurements were conducted at 39 receiver locations during off-peak and peak traffic conditions. The noise barrier reduced the noise level reaching adjacent residences substantially. Twenty-one residences (20 percent of the total in the study area) experienced a peak L10 insertion loss of 10 dBA or more, while another 63 residences (58 percent) were estimated as receiving an insertion loss of 5.0 to 9.9 dBA.
Comparison of insertion loss using levels predicted by the STAMINA 2.0 model with the barrier in place and measured levels were very close. Analyses indicated that insertion loss values predicted by the STAMINA 2.0 model will be achieved by the noise barrier .
A survey of community perception of the noise barrier was performed. Of 103 questionnaires delivered, 66 (64 percent) were returned. The community perception of the barrier was favorable, as 64 percent of the respondents generally liked the noise barrier and 95 percent felt it was effective in reducing traffic noise
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The photosynthetic acclimation response of Lolium perenne to four years growth in a free-air CO{sub 2} enrichment (FACE) facility
In this study, the photosynthetic responses of field grown Lolium perenne to ambient (354 {mu}mol mol{sup -1}) and elevated (600 {mu}mol mol{sup -1}) C{sub a} were measured. The experiment utilized the FACE facility at Eschikon, Switzerland; here the L. Perenne swards had been grown at two nitrogen treatments, with six cuts per year, for 4 years. The study revealed a significant decrease in Rubisco activity (Vcmax) in the low nitrogen FACE plots; this is consistent with the theories of source-sink imbalance resulting in feedback inhibition and down-regulation. Such negative acclimation was not wholly supported by diurnal investigations which revealed an average stimulation of 53.38% and 52.78% in the low and high nitrogen, respectively. However, light response curves and AI investigations also suggested down-regulation, especially in the low nitrogen. SI is expected to decrease in response to elevated C{sub a}, if any change is seen. This was indeed observed in the high nitrogen plots but for the low nitrogen a significant increase was found. Conclusions drawn from this project center around the implications of negative acclimation to future crop productivity. For instance, inter-specific differences in response to elevated C{sub a} may result in ecosystem changes and new management techniques may be necessary. However, real predictions cannot be made from leaf level studies alone as these may not represent the overall changes at the whole plant level
Analysis of Accidents Involving Breakaway-Cable-Terminal End Treatments
This report included an analysis of 50 accidents involving breakaway-cable-terminal (BCT) end treatments and 19 accidents involving median-breakaway-cable-terminal (BMCT) end treatments. The primary data base consisted of Kentucky accident records for the years 1980-82; with selected accidents included before 1980 and after 1982. An attempt was made to document each accident with a police report, photographs, and a maintenance repair form.
Results showed that the breakaway-cable-terminal end treatment performed properly in most accidents (72 percent); that is, the end treatment performed as it was designed with the wooden posts breaking away or the guardrail redirecting the vehicle. Only four impacts were known to involve small cars and the BCT performed properly in three of those accidents. If trucks are excluded from the analysis, the BCT performed properly in 63 percent of the collisions.
The MBCT end treatment performed properly in 50 percent of the accidents. Problems related to stiffness of the end treatment are most apparent when impact angles are shallow. A recommendation was made to remove any existing MBCT designs from gore area locations and replace them with a crash cushion. A new turned-down end treatment design was proposed for consideration at median installations
Analysis of Accidents Involving Crash Cushions
This report is an analysis of 127 accidents involving crash cushions in Kentucky. The primary data base was for the period 1980-82, with some additional data before and after this period. An attempt was made to document each accident with a police report, photographs, and a repair form. The largest number of accidents (63) involved a Hi-Dro cell cushion or cluster, followed by 33 accidents involving a G.R.E.A.T. crash cushion, 19 with a temporary G.R.E.A.T., 10 with sand barrels, and 2 with steel drums.
Average repair cost was lowest for the Hi-Dro cell cushion (2,839). Other repair costs were 887 for sand barrel installations, and $1,760 for steel drum installations.
For those accidents in which performance was noted, crash cushions performed properly 85 percent of the time. Instances of improper performance generally involved either a vehicle rebounding into or across the adjacent roadway or a vehicle overturning. All of the various types performed well.
Results from the cost-effectiveness analysis show that crash cushion installations produce a benefit-cost ratio in the range of 1.0 – 2.0
Problem Identification for Highway Safety Plan (FY 1984)
An annual highway safety program is proposed each year for the State of Kentucky in order to comply with Section 402, Title 23 of the United States Code. This program includes the identification, programming, budgeting, and evaluation of safety projects. This report is the fifth in a series of annual reports which have been included as the problem identification portion of Kentucky\u27s Annual Highway Safety Plan.
In the past, the approach to problem identification has been to identify problem areas in the 18 highway safety program areas (standards). While the search for problems in each of these standard areas will continue, certain program areas were identified for emphasis. The result was an analysis of 12 problem areas, with emphasis on alcohol and occupant protection. Recommendations were made for programs which could serve as countermeasures for the highway safety problems identified and for studies to develop and evaluate such programs
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