Major Lanes Research Articles

China-Russia collaboration in arctic shipping and maritime engineering

ABSTRACT In the past decades, climate change has been affecting the reduction of ice coverage in the Arctic Ocean and thus providing opportunities for the development of commercial navigation. Many countries are becoming increasingly interested in the exploration of opening maritime routes. Initiating the Polar Silk Road (PSR), China aims at the diversification of its trade routes and linking the markets of Asia and Europe within a network of transport and economic corridors. The initiative requires improvement of navigational safety and passability of the Northern Sea Route (NSR) and other major lanes in the Arctic seas. In this paper, the authors discuss how China may collaborate with Russia to ensure the development of secure navigable deep-water shipping routes in the Arctic and to partner in the engineering and construction of large-tonnage tankers and icebreakers. The paper presents an overview of the current condition of the shipbuilding industry in Russia in relation to the construction of vessels and marine equipment in such segments as icebreaking, transport, port, and dredging fleet. The authors conclude with a summary of the existing technological, engineering, and economic obstacles and opportunities for China in the light of the establishment of navigable maritime routes in the Arctic Ocean.

Recent developments and research needs in modeling lane changing

This paper comprehensively reviews recent developments in modeling lane-changing behavior. The major lane changing models in the literature are categorized into two groups: models that aim to capture the lane changing decision-making process, and models that aim to quantify the impact of lane changing behavior on surrounding vehicles. The methodologies and important features (including their limitations) of representative models in each category are outlined and discussed. Future research needs are determined.

Study on Merging Sign Installation in Work Zone of Expressway based on Changeable Critical Headway

The purpose of this research was to consider the vehicles’ changeable critical headway when driving along the upper work zone, and reducing conflicts and risks by merging in the end of the warning area, via installation of merging signage. A merging probability model was established by differential methods according to the M3 model and headway acceptance theory. According to the model, the appropriate position of merging signs was calculated in different traffic conditions. The influence of the merging probability by traffic parameters was analyzed, which indicated that the distance of merging signs had a positive correlation with the traffic volume; the distance of merging signs had a negative correlation with the proportion of free flow in the major lane; the distance of merging signs had a positive correlation with the vehicles’ speed in the major lane; the establishing of merging signs should be combined with the speed limiting.

Moderate sleep restriction in treated older male OSA participants: Greater impairment during monotonous driving compared with controls

To examine the effects on monotonous driving of normal sleep versus one night of sleep restriction in continuous positive airway pressure (CPAP) treated obstructive sleep apnoea (OSA) patients compared with age matched healthy controls. Nineteen CPAP treated compliant male OSA patients (OSA-treated patients (OPs)), aged 50-75 years, and 20 healthy age-matched controls underwent both a normal night's sleep and sleep restriction to 5h (OPs remained on CPAP) in a counterbalanced design. All participants completed a 2h afternoon monotonous drive in a realistic car simulator. Driving was monitored for sleepiness-related minor and major lane deviations, with 'safe' driving time being total time driven prior to first major lane deviation. EEGs were recorded continuously, and subjective sleepiness ratings were taken at regular intervals throughout the drive. After a normal night's sleep, OPs and controls did not differ in terms of driving performance or in their ability to assess the levels of their own sleepiness, with both groups driving 'safely' for approximately 90 min. However, after sleep restriction, OPs had a significantly shorter (65 min) safe driving time and had to apply more compensatory effort to maintain their alertness compared with controls. They also underestimated the enhanced sleepiness. Nevertheless, apart from this caveat, there were generally close associations between subjective sleepiness, likelihood of a major lane deviation and EEG changes indicative of sleepiness. With a normal night's sleep, effectively treated older men with OSA drive as safely as healthy men of the same age. However, after restricted sleep, driving impairment is worse than that of controls. This suggests that, although successful CPAP treatment can alleviate potential detrimental effects of OSA on monotonous driving following normal sleep, these patients remain more vulnerable to sleep restriction.

THE CONTRIBUTION TO THE PROCEDURE OF CAPACITY DETERMINATION AT UNSIGNALIZED PRIORITY-CONTROLLED INTERSECTIONS

The problem of minor vehicles crossing or merging into themajor stream at unsignalized priority-controlled intersections iswell-known. Numerous solutions involve various assumptionsconcerning the major headway distributions, number of majorlanes, critical gap distributions, etc. Such cases can be dividedinto two main groups: intersections with two streams (one majorand one minor stream) and intersections with more thantwo streams (more than one major stream and one minorstream). At roundabouts, also at single-lane roundabouts,there are similar problems like the ones at other unsignalizedpriority-controlled intersections. A vehicle at the roundaboutapproach can only cross the pedestrian crossing when a sufficienttime-gap between two pedestrians (or cyclists) is provided.A vehicle at the roundabout entries can only merge into the majorstream when a sufficient gap between the two vehicles in themajor stream is provided. Because of that, single-lane roundaboutscan also be treated as unsignalized intersections withtwo major lanes: the first one in its circulatory roadway and thesecond one on the pedestrian crossing.

Capacity of Unsignalized Intersections with Mixed Vehicle Flows

On the basis of gap-acceptance theory, mixed traffic flow composed of two representative vehicle types—heavy and light vehicles—is analyzed with probability theory. A capacity model is set up for an unsignalized intersection in which the minor-stream mixed traffic flows cross m major lanes and the traffic flow headways fit the M3 distribution; it is an extension of minor-lane capacity theory for one vehicle type and one major-stream traffic flow. A more complicated case with minor-stream flow composed of discretionary vehicle types is also considered, and the corresponding formula is given. After field testing in China, the conclusion is drawn that this model is better for analyzing Chinese traffic conditions than are other existing models.

Estimation of critical gaps in two major streams

Different authors have presented capacity formulas for the case of more than one major lane when the lanes are not superposed. It has been shown that the allocation of the major flow on to the different lanes and different critical gaps for the major lanes have a substantial effect on the capacity for a minor lane. In this paper a maximum likelihood method for estimating the different critical gaps for the case of two major lanes is presented. The method can handle possible linear correlation between the critical gaps for the two major lanes. It is tested on simulated data and then applied on real data. It is then shown that the critical gaps differ between the two major lanes. The correlation coefficient was estimated for some of the subsets but for most of the subsets it was not possible to estimate.

A further generalization of Tanner’s formula

A general capacity formula for the case of more than one major lane is derived, using the M3 distribution and allowing the major lanes to differ in critical gaps and follow-up times. The derivation can be further extended to there being different minimum headways for the major lanes and to distributions other than the M3 distribution. It is shown that the resulting formulas provide more accurate capacity estimations.