Safety of U-Turns at Unsignalized Median Openings

2005 ◽  
Vol 1912 (1) ◽  
pp. 72-81 ◽  
Author(s):  
Herbert S. Levinson ◽  
Ingrid B. Potts ◽  
Douglas W. Harwood ◽  
Jerome Gluck ◽  
Darren J. Torbic
Keyword(s):  
Safety Concern ◽  
Management Strategies ◽  
Field Studies ◽  
Left Turn ◽  
Detailed Classification ◽  
Local Access ◽  
Accident Data ◽  
State And Local ◽  
Median Opening ◽  
Alternate Routes

Many state and local transportation agencies install nontraversable medians on multilane highways to improve safety and travel times and to manage local access better. While nontraversable medians restrict direct left-turn access to and from adjacent developments, traffic destined for these locations must use alternate routes, some of which may involve making U-turns at nearby median openings–-a movement often referred to as an indirect left turn. Until recently, the safety effects of increased U-turn volumes have been largely unknown. NCHRP Project 17–21, Safety of U-Turns at Unsignalized Median Openings, documented the safety performance and operational effects of U-turns at median openings. This paper presents the key findings from that research. It presents a summary of key literature and current highway agency practice related to median openings, a detailed classification scheme for median openings, and a summary of the results of comprehensive field studies. The research results indicate that access management strategies that increase U-turn volumes at unsignalized median openings can be used safely and effectively. Analysis of accident data found that accidents related to U-turn and left-turn maneuvers at unsignalized median openings occur infrequently. In urban arterial corridors, unsignalized median openings experienced an average of 0.41 U-turn-plus-left-turn accidents per median opening per year. In rural arterial corridors, unsignalized median openings experienced an average of 0.20 U-turn-plus-left-turn accidents per median opening per year. On the basis of these limited accident frequencies, there is no indication that U-turns at unsignalized median openings are a major safety concern.

Improving Speech and Language Services through Effective Time Management

1983 ◽  
Vol 14 (2) ◽  
pp. 86-91 ◽  
Author(s):  
Barbara W. Travers
Keyword(s):  
Time Management ◽  
Management Strategies ◽  
Federal State ◽  
Speech Language Pathologist ◽  
School Based ◽  
Work Area ◽  
Paper Work ◽  
Areas Of Concern ◽  
State And Local ◽  
Therapeutic Services

This paper presents strategies for increasing the effectiveness and efficiency of the school-based speech-language pathologist. Various time management strategies are adapted and outlined for three major areas of concern: using time, organizing the work area, and managing paper work. It is suggested that the use of such methods will aid the speech-language pathologist in coping with federal, state, and local regulations while continuing to provide quality therapeutic services.

scholarly journals Interactions of Nitrogen Source and Rate and Weed Removal Timing Relative to Nitrogen Content in Corn and Weeds and Corn Grain Yield

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Alexandra M. Knight ◽  
Wesley J. Everman ◽  
David L. Jordan ◽  
Ronnie W. Heiniger ◽  
T. Jot Smyth
Keyword(s):  
Grain Yield ◽  
Weed Management ◽  
Management Strategies ◽  
Field Studies ◽  
Weed Species ◽  
Weed Interference ◽  
Coated Urea ◽  
N Fertility ◽  
Corn Grain ◽  
Corn Grain Yield

Adequate fertility combined with effective weed management is important in maximizing corn (Zea mays L.) grain yield. Corn uptake of nitrogen (N) is dependent upon many factors including weed species and density and the rate and formulation of applied N fertilizer. Understanding interactions among corn, applied N, and weeds is important in developing management strategies. Field studies were conducted in North Carolina to compare corn and weed responses to urea ammonium nitrate (UAN), sulfur-coated urea (SCU), and composted poultry litter (CPL) when a mixture of Palmer amaranth (Amaranthus palmeri S. Wats.) and large crabgrass (Digitaria sanguinalis L.) was removed with herbicides at heights of 8 or 16 cm. These respective removal timings corresponded with 22 and 28 days after corn planting or V2 and V3 stages of growth, respectively. Differences in N content in above-ground biomass of corn were noted early in the season due to weed interference but did not translate into differences in corn grain yield. Interactions of N source and N rate were noted for corn grain yield but these factors did not interact with timing of weed control. These results underscore that timely implementation of control tactics regardless of N fertility management is important to protect corn grain yield.

scholarly journals Preserving Wildlife: An International Perspective

2001 ◽  
Vol 7 (2) ◽  
pp. 146
Author(s):  
Nadia Elizabeth Tapp
Keyword(s):  
Wildlife Management ◽  
Native Species ◽  
Captive Breeding ◽  
Management Strategies ◽  
Field Studies ◽  
Moral Values ◽  
International Perspective ◽  
Management Approaches ◽  
Sport Hunting ◽  
Selection Of

PRESERVING Wildlife: An International Perspective is an anthology of twenty papers exploring the issues related to the preservation of wildlife, with an emphasis on related management approaches. This topic is introduced philosophically with a discussion of moral values associated with human activities. Sport hunting, the medical aid of injured wild animals and the manipulation of wildlife during ecological field studies are discussed within this context. The focus then shifts to a selection of wildlife management strategies including habitat protection, captive breeding, culling of non-native species, eco-tourism and marketing of wildlife products.

Volunteer potato interference in carrot

Weed Science ◽  
2006 ◽  
Vol 54 (1) ◽  
pp. 94-99 ◽  
Author(s):  
Martin M. Williams ◽  
Rick A. Boydston
Keyword(s):  
Weed Management ◽  
Yield Loss ◽  
Management Strategies ◽  
Field Studies ◽  
Functional Relationships ◽  
Weed Growth ◽  
Volunteer Potato ◽  
Tuber Production ◽  
Hand Weeding ◽  
Management Recommendations

Weed management systems in carrot are limited in part by a lack of fundamental understanding of crop–weed interactions. Irrigated field studies were conducted to quantify the effect of volunteer potato density and duration of interference on carrot yield and to determine relationships among weed density, duration of weed growth, and volunteer potato tuber production. A season-long volunteer potato density of 0.06 plants m−2produced from 150 to 230 g tubers m−2and resulted in an estimated 5% crop yield loss. At two volunteer potato plants m−2, the same level of crop loss was estimated with a duration of interference of 430 growing degree days (GDD), a time at which the weed had already produced 130 g tubers m−2. Volunteer potato height at the time of weed removal predicted carrot yield loss (R2= 0.77) and may be useful for timing of management strategies such as hand weeding. Functional relationships describing carrot–volunteer potato interactions provide simple information that is useful for developing weed management recommendations for carrot, a crop that relies on multiple tactics for managing weeds, and rotational crops that are negatively affected by persistence of volunteer potato.

Crisis in Mali: Interrelationship of major actors

2021 ◽  
pp. 47
Author(s):  
Anna S. Davidchuk
Keyword(s):  
Field Studies ◽  
Comprehensive Analysis ◽  
Political Agenda ◽  
General Level ◽  
Complex Nature ◽  
Challenges And Opportunities ◽  
Terrorist Groups ◽  
State And Local ◽  
Sahel Region ◽  
The Relationship

This article provides comprehensive analysis of interrelationship of the main actors of Malian conflict in 2012-2021, based on official statements, documents, press reports and field studies. The analysis is focused on the main groups of actors and the complex nature of relationships within the system, based on the "mutual intersection" of actors at several levels - transnational, state and local (ethnic). The authors consider a complex of political and economic reasons that affects the change in the loyalty of actors - the general level of poverty, the issue of controlling routes of smuggling and drug trafficking, the unique political agenda of different groups, close tribal, family and friendly ties between representatives of the same classes and clans representing different actors. In the paper are also analyzed the main events that make it possible to talk about the type of relations between actors. Researchers pay special attention to non-state actors - former rebels and ethnic militias, which form the systems of relations among the actors of the Malian conflict and actively use violence, the monopoly on which de jure belongs only to the state. Authors analyze the position of foreign actors (France, EU, UN) and emergence of new, non-violent methods of combating terrorism, since the anti-terrorist operations "Serval" and "Barkhan" were not successful and did not destroy the terrorist groups in the Sahara-Sahel region. All these facts signal about a further change in the relationship among the actors and, as a result, new challenges and opportunities in the settlement of the Malian conflict.

Pathogen suppression by microbial volatile organic compounds in soils

2019 ◽  
Vol 95 (8) ◽  
Author(s):  
Wietse de Boer ◽  
Xiaogang Li ◽  
Annelein Meisner ◽  
Paolina Garbeva
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Abiotic Factors ◽  
Management Strategies ◽  
Field Studies ◽  
Growth Media ◽  
Soil Borne Pathogens ◽  
Volatile Organic ◽  
Microbial Volatile Organic Compounds ◽  
Pathogen Suppression

ABSTRACT There is increasing evidence that microbial volatile organic compounds (mVOCs) play an important role in interactions between microbes in soils. In this minireview, we zoom in on the possible role of mVOCs in the suppression of plant-pathogenic soil fungi. In particular, we have screened the literature to see what the actual evidence is that mVOCs in soil atmospheres can contribute to pathogen suppression. Furthermore, we discuss biotic and abiotic factors that influence the production of suppressive mVOCs in soils. Since microbes producing mVOCs in soils are part of microbial communities, community ecological aspects such as diversity and assembly play an important role in the composition of produced mVOC blends. These aspects have not received much attention so far. In addition, the fluctuating abiotic conditions in soils, such as changing moisture contents, influence mVOC production and activity. The biotic and abiotic complexity of the soil environment hampers the extrapolation of the production and suppressing activity of mVOCs by microbial isolates on artificial growth media. Yet, several pathogen suppressive mVOCs produced by pure cultures do also occur in soil atmospheres. Therefore, an integration of lab and field studies on the production of mVOCs is needed to understand and predict the composition and dynamics of mVOCs in soil atmospheres. This knowledge, together with the knowledge of the chemistry and physical behaviour of mVOCs in soils, forms the basis for the development of sustainable management strategies to enhance the natural control of soil-borne pathogens with mVOCs. Possibilities for the mVOC-based control of soil-borne pathogens are discussed.

Evaluation of a Training Intervention to Improve Novice Drivers’ Hazard Mitigation When Approaching Left Turn Scenarios

2019 ◽  
Vol 2673 (12) ◽  
pp. 474-484
Author(s):  
Jeffrey W. Muttart ◽  
Swaroop Dinakar ◽  
Donald L. Fisher ◽  
Teena M. Garrison ◽  
Siby Samuel
Keyword(s):  
Video Game ◽  
Driving Simulator ◽  
Phase 1 ◽  
Hazard Mitigation ◽  
Management Strategies ◽  
Crash Risk ◽  
Novice Drivers ◽  
Left Turn ◽  
Street Sign ◽  
Teenage Drivers

Crash statistics reveal that newly licensed teenage drivers experience a higher risk of crashing than more experienced drivers, particularly when turning left across the path of approaching traffic. Research has also demonstrated that novice drivers exhibit poor hazard mitigation skills. The current study assesses the effectiveness of a training program aimed at improving novice drivers’ hazard mitigation and speed selection behaviors as both the through driver and turning driver in left turn across path scenarios. In this study, novice drivers were randomly assigned to one of two training cohorts: anticipation-control-terminate (ACT) or placebo. Phase 1 of ACT is a video game where drivers must select where to look, where they would steer, and when they would slow when observing the approach to known fatal crash risk scenarios. Placebo training involved reaction time tests and street sign definitions. In phase 2 the ACT-trained participants were shown where their choices were similar to, or different than, those of drivers aged 26 through 61who had not had crashed in the previous 10 years. In phase 3, ACT-trained drivers were compared with placebo-trained drivers at left turn scenarios both as through driver and turning driver, using a driving simulator. ACT-trained drivers were more likely to exhibit anticipatory glances and slowing behaviors, and were significantly less likely to crash than were placebo-trained drivers. The results indicate that ACT was effective as a countermeasure for training novice drivers to select better speed management strategies in the simulated scenarios utilized in this research.

scholarly journals Between Home and Work: Commuting as an Opportunity for Role Transitions

2020 ◽  
Author(s):  
Jon M. Jachimowicz ◽  
Julia Lee Cunningham ◽  
Bradley R. Staats ◽  
Francesca Gino ◽  
Jochen I. Menges
Keyword(s):  
Family Conflict ◽  
Management Strategies ◽  
Field Studies ◽  
Self Control ◽  
Work Role ◽  
Boundary Management ◽  
Daily Routine ◽  
Work Family Conflict ◽  
Work Related ◽  
Work Family

Across the globe, every workday people commute an average of 38 minutes each way, yet surprisingly little research has examined the implications of this daily routine for work-related outcomes. Integrating theories of boundary work, self-control, and work-family conflict, we propose that the commute to work serves as a liminal role transition between home and work roles, prompting employees to engage in boundary management strategies. Across three field studies (n = 1,736), including a four-week-long intervention study, we find that lengthy morning commutes are more aversive for employees with lower trait self-control and greater work-family conflict, leading to decreased job satisfaction and increased turnover. In addition, we find that employees who engage in a specific boundary management strategy we term role-clarifying prospection (i.e., thinking about the upcoming work role) are less likely to be negatively affected by lengthy commutes to work. Results further show that employees with higher levels of trait self-control are more likely to engage in role-clarifying prospection, and employees who experience higher levels of work-family conflict are more likely to benefit from role-clarifying prospection. Although the commute to work is typically seen as an undesirable part of the workday, our theory and results point to the benefits of using it as an opportunity to transition into one’s work role.

scholarly journals Trap type and positioning: how to trap Savi’s pine voles using the tunnel system

Mammalia ◽  
2018 ◽  
Vol 82 (4) ◽  
pp. 350-354 ◽  
Author(s):  
Filippo Dell’Agnello ◽  
Valeria Mazza ◽  
Matilde Martini ◽  
Sandro Bertolino ◽  
Dario Capizzi ◽  
...  
Keyword(s):  
Small Mammals ◽  
Management Strategies ◽  
Field Studies ◽  
Nesting Material ◽  
Vole Species ◽  
Social Habits ◽  
Tunnel System ◽  
Microtus Savii ◽  
Capture Rates

Abstract Savi’s pine vole, Microtus savii, is the most widespread Italian vole species, an important rodent pest in agriculture and yet one of the least studied species. One of the reasons for this gap in knowledge is that members of this species are quite difficult to capture with standard trapping procedures, being fossorial and rarely active aboveground. For this reason, we developed a protocol that maximizes trapping success. This method requires the identification of active tunnel holes and the placement of traps directly in front of the exits. We also compared capture and recapture rates of Savi’s pine voles in three different trap types: Institut National de la Recherche Agronomique (INRA), Longworth and Ugglan. If properly equipped with food and nesting material, INRA, Longworth and Ugglan traps showed similar capture rates, but the recapture rate of Ugglan traps was the highest of the three kinds of traps. These results, in combination with the species’ fossorial and social habits, lead us to conclude that Ugglan traps are the best suited for studies on Savi’s pine voles. Our results may have implications for planning and implementing management strategies based on traps rather than rodenticides, as well as field studies on other fossorial small mammals.

Modelling the demography of crenate broomrape (Orobanche crenata) as affected by broad bean (Vicia faba) cropping frequency and planting date

Weed Science ◽  
1997 ◽  
Vol 45 (2) ◽  
pp. 261-268 ◽  
Author(s):  
Francisca López-Granados ◽  
Luis García-Torres
Keyword(s):  
Broad Bean ◽  
Management Strategies ◽  
Field Studies ◽  
Planting Date ◽  
Planting Dates ◽  
Cropping Frequency ◽  
Seed Loss ◽  
Model Predictions ◽  
Reported Data

A mathematical model of crenate broomrape populations in broad bean as affected by cropping frequency and planting dates in the absence of crenate broomrape control practices was constructed using previously reported data. In consecutive broad bean cropping, broomrape populations reached a maximum infection severity (D) of 62, 47, and 30 emerged broomrape m−2for early (mid-October), intermediate (mid-November), and late (mid-December) planting dates, respectively. The maximumDvalues were reached earlier as planting dates were brought forward, taking from 4 to 6 yr, starting from very low initial infections (D ≤0.2 emerged broomrape m−2). If broad bean was cropped every 3 yr, 15, 21, and 27 yr were needed, respectively, according to the model, to reach the maximumDfor the three planting dates considered. A sensitivity analysis was conducted to determine the effect of changing the values of the main demographic parameters in broomrape life cycle (germination, attachment, and seed loss) on the output of the model under different management strategies (planting dates and cropping frequency). Generally, an increase in seed attachment and a decrease in seed loss affected broomrape population dynamics. Between the two processes evaluated, the time taken to reach the maximum infection severity (D) was less sensitive than the maximum broomrape population values. Model predictions were validated using results from long-term field studies at the late planting date sown every year. Simulated values generated good predictions (R2= 0.82).

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