8,201 research outputs found
Elements of Median Design in Relation to Accident Occurrence
The purpose of this study was to compare the accident histories of different median types and to provide verification of generally recommended median widths and slopes. A major limitation of the analyses was the small number of possible combinations of median width and cross slope available for study.
The analyses reported provided evidence from accident histories to support the general requirement that wider medians are safer medians. It was indicated that medians should be a minimum of 30-40 feet wide for high speed facilities and that flat slopes should be provided; 4:1 slopes are inadequate for medians less than 60 feet wide. There was an indication that 6:1 or flatter slopes should be used. Raised medians provided an unsuitable vehicle recovery area on rural highways and were also undesirable from the standpoint of roadway surface drainage. The irregular interstate medians which result from independent roadway alignment should be used only with adequate clear zones in the median. Twelve-foot shoulders should be provided where guardrail is to be used
The effect of simultaneous and sequential presentation of stimulus dimensions on absolute judgment accuracy
Permutation combinatorics of worldsheet moduli space
52 pages, 21 figures52 pages, 21 figures; minor corrections, "On the" dropped from title, matches published version52 pages, 21 figures; minor corrections, "On the" dropped from title, matches published versio
Big end bearing losses with thermal cavitation flow under cylinder deactivation
The paper presents a mixed thermo-hydrodynamic analysis of elliptic bore bearings using combined solution of NavierâStokes, continuity and energy equations for multi-phase flow conditions. A vapour transport equation is also included to ensure continuity of flow in the cavitation region for the multiple phases as well as RayleighâPlesset to take into account the growth and collapse of cavitation bubbles. This approach removes the need to impose artificial outlet boundary conditions in the form of various cavitation algorithms which are often employed to deal with lubricant film rupture and reformation. The predictions show closer conformance to experimental measurements than have hitherto been reported in the literature. The validated model is then used for the prediction of frictional power losses in big end bearings of modern engines under realistic urban driving conditions. In particular, the effect of cylinder deactivation (CDA) upon engine bearing efficiency is studied. It is shown that big-end bearings losses contribute to an increase in the brake specific fuel consumption with application of CDA contrary to the gains made in fuel pumping losses to the cylinders. The study concludes that implications arising from application of new technologies such as CDA should also include their effect on tribological performance
Recommended from our members
Motherhood, Moral Authority and the Charismatic Matriarch in the Aftermath of Lethal Violence
Images of maternal suffering are an evocative and powerful means of communication in a world where the private grief of victims has increasingly become subject to commodification and public consumption. This article looks at the influence of bereaved mothers as symbols of respect, peace and dignity in the aftermath of violence, and as a result their persuasive presence in family activism. Drawing upon two case studies, this article explores the importance of victimsâ stories in public life and, in particular, the presence of the charismatic matriarch in creating communities of solidarity, raising awareness of harms that have previously gone unheard and prompting policy change. It considers the âcanonicalâ story of the mother in public life and concludes by arguing that more attention should be paid to victimsâ stories and their influence on policy-making, politics and eventually in becoming public grievances
- âŚ