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Interchanges are constructed in urban and suburban areas to ease traffic operation. Outer connection ramps constitute a major part of interchanges planning and design. The objective of this study was to estimate interchange ramp capacity and investigate the impacts of ramp geometry on the obtained capacity. To achieve this objective, 20 ramps were selected, including 10 circular ramps and 10 curve-straight-curve ramps. Capacity of ramp proper and ramp exit were investigated in the study. At ramp proper, data on traffic speed and traffic flow were collected at 1 -minute intervals using video camera. Also, traffic data for ramp exit and mainline traffic were obtained under queued traffic condition on the ramp exit. An empirical approach using regression analysis was adopted to estimate capacity of the selected ramps and explore the impact of geometric design and traffic variables that might affect the estimated capacity. For ramp proper, the analyses revealed that the relationship between traffic speed and density is linear and between speed and traffic flow is parabolic irrespective of ramp configuration. For circular ramps, the capacity was found to vary from 1470 to about 2100 pc/hr./lane, and it was found that ramp radius is the most influencing factor in capacity estimation. For curve-straight-curve ramps, the results indicated that the obtained capacity varied from 1490 to 2200 pc/hr./lane, and both the straight segment length and the radius of the first curve are the most influencing factors. Also, it was found that ramp exit capacity is affected by flow and speed of traffic in the mainline street and degree of curvature of ramp exit curve. Finally, it was concluded that the use of curves with large radii at ramp proper and exit would increase ramp capacity, and customization of capacity values to reflect local conditions would provide more realistic estimates. [ABSTRACT FROM AUTHOR]

Aims and objectives To (1) identify the perceptions of Jordanian patients who suffer from coronary artery diseases towards nurse caring behaviours in critical care units; (2) identify the perceptions of Jordanian nurses who work in critical care units towards nurse caring behaviours; and (3) compare the perceptions of both patients and nurses towards nurse caring behaviours in critical care units. Background Caring is an important concept in nursing, when nursing behaviours were perceived by patients as caring behaviours, and thus, their satisfaction with the quality of care can be improved. Therefore, it is important for nurses to be knowledgeable about the caring behaviours as perceived by patients who complained from coronary artery diseases themselves. Design A descriptive comparative design was used. Methods A convenience sample of 150 patients who complained from coronary artery diseases and 60 critical care unit nurses completed the demographic form and the Caring Behavior Assessment scale. Results Patients in critical care units perceived physical and technical behaviours as most important caring behaviours, whereas nurses in critical care units perceived teaching behaviours as most important caring behaviours. Conclusion There were significant differences between patient participants' and nurse participants' perceptions towards four subscales of Caring Behavior Assessment scale that should be considered when caring for patients with coronary artery diseases. Relevance to clinical practice Patients with coronary artery diseases need well-trained and clinically competent nurses to meet their needs. 'Spiritual needs' was an important nurse caring behaviour that should be emphasised in nursing practice. [ABSTRACT FROM AUTHOR]

The purpose of this research was to develop a model for estimating roundabout delay as a function of the influencing traffic and geometric factors. Fourteen roundabouts were selected from different cities in Jordan. Circulating volume, entry volume, and entry delay were measured during peak and off-peak periods using video cameras. Data on geometric design elements including circulating width, entry width, and roundabout diameter were measured through field survey. An empirical approach was used to develop a delay model as a function of the influencing factors based on a time interval of 15 min. The analysis indicated that geometric variables have significant effects on the roundabout entry delay. The entry width has the greatest influence, whereas the circulating width has the least influence. A comparison between delay models produced using different time intervals showed that, as time interval increases, R[sup 2] increases. The SIDRA delay model was validated using the field delay data, and it was found that it overestimates the delay, especially at high delay ranges. The M/M/1 (random arrivals, random services, and a single service channel) queuing delay model was also validated using the field delay data, and it was found that it estimates delay with high variability, especially for high delay ranges. [ABSTRACT FROM AUTHOR]