Suchergebnisse

The kalimalang highway is a connecting road between the city of Jakarta and Bekasi, the high mobility of passenger vehicles and goods is a problem of congestion that must be minimized. The volume of vehicles on the Kalimalang highway has increased quite high each year, but this has not been matched by growth in capacity. Therefore the government plants to build the Becakayu toll road to reduce congestion. This study aims to determine bottlenecks that occur due to the construction of an off-ramp on the Becakayu toll road, especially in section 2A, which is located on Jl. Veteran, while the location under review is the intersections affected by the construction of the off-ramp including the intersection of four signaling BCP, intersection of four signaling Veteran and Sarbini unsigned intersection, Data analysis in this study uses the MKJI 1997 method. From this method displays the behavior of traffic, for signal intersections will display signal time, capacity, vehicle stopped ratio, queue length, and average delay and for unsignalized intersections will display capacity, average delay and queue opportunity. From the results of this study it was found that the signaled intersection had an average value of DS > 1, so for the service level at the intersection is the current forced / jammed with low speed. Where the largest queue length occurred 1876.7 m, an average delay of 210.30 SMP/ sec, and vehicles stopped at an average of 7378 SMP/hour. And for unsignalized intersections having an average DS <0.45, the service level at the intersection is a stable flow with operating speed starting to be limited by traffic conditions, this intersection has the greatest queue probability (QP%) 8.48-20.35 in the Saturday time period - afternoon and intersection delay 9.5 SMP / sec.

The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013) / ERC Grant Agreement n. 321132, project TRAMAN21. ; Summarization: The well-known feedback ramp metering algorithm ALINEA can be applied for local ramp metering or included as a key component in a coordinated ramp metering system. ALINEA uses real-time occupancy measurements from the ramp flow merging area that may be at most a few hundred meters downstream of the metered on-ramp nose. In many practical cases, however, bottlenecks with smaller capacities than the merging area may exist further downstream, which suggests using measurements from those downstream bottlenecks. Recent theoretical and simulation studies indicate that ALINEA may lead to poorly damped closed-loop behavior in this case, but PI-ALINEA, a suitable Proportional-Integral (PI) extension of ALINEA, can lead to satisfactory control performance. This paper addresses the same local ramp-metering problem in the presence of far-downstream bottlenecks, with a particular focus on the employment of PI-ALINEA to tackle three distinct cases of bottleneck that may often be encountered in practice: (1) an uphill case; (2) a lane-drop case; and (3) an un-controlled downstream on-ramp case. Extensive simulation studies are conducted on the basis of a macroscopic traffic flow model to show that ALINEA is not capable of carrying out ramp metering in these bottleneck cases, while PI-ALINEA operates satisfactorily in all cases. A field application example of PI-ALINEA is also reported with regard to a real case of far downstream bottlenecks. With its control parameters appropriately tuned beforehand, PI-ALINEA is found to be universally applicable, with little fine-tuning required for field applications. ; Presented on: Transportation Research Part C: Emerging Technologies

The importance of the "Ramp-up bridge" covering the gap between product development and serial production, as well as the speed at which this bridge can be crossed, has increased, providing companies with a significant competitive advantage.However, a significant percentage of project aiming to introduce new products do not achieve their goals. [(60 percent of the automotive supplier ramp-up projects fail on either the technical, or the economic side (Bischoff, 2007)].The author explores the possible reasons, then makes suggestions regarding the support of successful ramp-up projects, through practical examples taken from the industry. Through the continuous improvement of ramp-ups, a new core competency can be achieved, with a decrease in time-to-market. This core competency is difficult to duplicate, and can provide an additional competitive advantage for companies manufacturing products with high technical complexity.

In the last decades, climate change has placed the issue of environmental and social sustainability at the heart of discussions about energy consumption .In the fight against climate change, the European Union has to promote the development of renewable energy sources.Several OS/TSO are claiming that the ramp requirements due to renewable generation are increasing and require new flexibility mechanisms to provide firm generation ramp support.The objective of this work is to perform an historical analysis of the firm generation ramp requirement of Portugal according to the penetration level of renewable generation, and to extend this analysis to future scenarios with different levels of penetration of wind and solar generation.

The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013) / ERC Grant Agreement n. 321132, project TRAMAN21. ; Summarization: This study aims to provide insights and demonstrate the properties and the performance of a nonlinear adaptive control scheme which has been recently developed to address the ramp metering problem arising in freeways. The proposed scheme consists of a nominal feedback law in conjunction with a nonlinear observer which aims to estimate some unknown system variables. A distinguishing novelty of the proposed approach is that it can inherently be applied both at local and coordinated levels. The control scheme is tested for realistic traffic scenarios using a macroscopic traffic flow simulator as a surrogate for potential field application. Comparison tests have been performed with other control strategies proposed in the literature and employed already in the field. ; Presented on:

Reliability of travel time is increasingly becoming an important part of transport policies around the world. However, a recent review of policies in OECD countries shows that despite its importance, only few countries monitor reliability or explicitly incorporate reliability into transport policy making. The role of the government may be crucial in delivering optimal levels of reliability. A number of policy options are available to improve reliability. Active management of the network through ramp metering is recognized as an efficient way to control motorway traffic and field tests of ramp control strategies show benefits on average travel time. Far less is said on reliability benefits of ramp metering. There are only few studies that specifically monitor improvements in travel time variability. In this paper we present findings on a case study of applying ramp metering on a French motorway A6W near Paris. We apply a number of indicators for travel time variability before and after introducing ramp metering. In order to take into account reliability in policy impact evaluation, cost-benefit assessment provides consistent framework to assess the monetised benefits. We therefore also calculate monetary value of reliability benefits of ramp metering and finally discuss policy implications of our results. We suggest that failing to unbundle time saving benefits of a project between average travel time and the variability in travel time is likely to lead to sub-optimal policy solutions. We also argue that managing existing capacity better can be a cost-effective way to improve both average travel time and the variability in travel time.

Reliability of travel time is increasingly becoming an important part of transport policies around the world. However, a recent review of policies in OECD countries shows that despite its importance, only few countries monitor reliability or explicitly incorporate reliability into transport policy making. The role of the government may be crucial in delivering optimal levels of reliability. A number of policy options are available to improve reliability. Active management of the network through ramp metering is recognized as an efficient way to control motorway traffic and field tests of ramp control strategies show benefits on average travel time. Far less is said on reliability benefits of ramp metering. There are only few studies that specifically monitor improvements in travel time variability. In this paper we present findings on a case study of applying ramp metering on a French motorway A6W near Paris. We apply a number of indicators for travel time variability before and after introducing ramp metering. In order to take into account reliability in policy impact evaluation, cost-benefit assessment provides consistent framework to assess the monetised benefits. We therefore also calculate monetary value of reliability benefits of ramp metering and finally discuss policy implications of our results. We suggest that failing to unbundle time saving benefits of a project between average travel time and the variability in travel time is likely to lead to sub-optimal policy solutions. We also argue that managing existing capacity better can be a cost-effective way to improve both average travel time and the variability in travel time.