Highlights Life stages associate with telework behavior in a complex way. Irrespective of gender and marital status, parents are less likely to telework compared to those without children. Regarding individuals without children, single individuals are more likely to telework than married ones, and males are more likely to telework than females. For individuals with children, the partnered parents are more likely to telework than the single parents, and females are more likely to telework than males.

Intermediate modes of transport, such as shared vehicles or ride sharing, are starting to increase their market share at the expense of traditional modes of car, public transport, and taxi. In the advent of autonomous vehicles, single occupancy shared vehicles are expected to substitute at least in part private conventional vehicle trips. The objective of this paper is to estimate the impact of shared autonomous vehicles on average trip duration and vehicle-km traveled in a large metropolitan area. A stated preference online survey was designed to gather data on the willingness to use shared autonomous vehicles. Then, commute trips and home-based other trips were generated microscopically for a synthetic population in the greater Munich metropolitan area. Individuals who traveled by auto were selected to switch from a conventional vehicle to a shared autonomous vehicle subject to their willingness to use them. The effect of shared autonomous vehicles on urban mobility was assessed through traffic simulations in MATSim with a varying autonomous taxi fleet size. The results indicated that the total traveled distance increased by up to 8% after autonomous fleets were introduced. Current travel demand can still be satisfied with an acceptable waiting time when 10 conventional vehicles are replaced with 4 shared autonomous vehicles.

In this paper, the required models and methods to analyze and quantify the potential demand for urban air mobility (UAM) complementing public transport and possible impacts were defined and applied to the Munich Metropolitan region. An existing agent-based transport model of the study area were used and extended to cover socio-demographic changes up to the year 2030 and intermodal UAM services. An incremental logit model for UAM was derived to simulate demand for this new mode. An airport access model was developed as well. Three different UAM networks with different numbers of vertiports were defined. Sensitivity studies of ticket fare and structure, flying vehicle cruise speed, passenger process times at vertiports and different Urban Air Mobility networks sizes were performed. For the reference case, UAM accounts for a modal share of 0.5%. The absolute UAM demand is concentrated on very short routes; hence, UAM vehicle flight speed variation shows low UAM demand impacts. Kilometer-based fare, number of UAM vehicles per vertiport and passenger process times at vertiports show a significant impact on UAM demand.

Pyrylium-containing mesoporous materials have been used for the chromo-fluorogenic sensing of biogenic amines in an aqueous environment.Biologically active amines are ubiquitous chemical compounds that play an important role in many different areas. Depending on their chemical composition and origin, basically two different groups can be found. A major group are the so-called biogenic amines that are formed in the normal metabolism of animals, plants and micro-organisms via decarboxylation of the respective amino acid through substrate-specific enzymatic reactions. The formation of these biogenic amines is undesirable in foods and beverages because they can induce headaches, respiratory distress, heart palpitations and several allergenic disorders. 1 Histamine is the most toxic of the biogenic amines and the main cause of scombroid poisoning by acting synergistically with other amines. Thus, the level of biogenic amines in a food product is a quality index and the development of easy-to-use determination protocols is of interest. The second group are fatty amines such as sphingosine (a fatty amine that carries two additional hydroxyl groups in the polar head region) and its close metabolites that are important cellular messengers and have a profound impact on e.g. mitosis and apoptosis. 2 Other fatty amines, that usually stem form anthropogenic sources, are simple amines with a chain length > C 10 that find wide-spread application in corrosion inhibition, asphalt emulsions or as petroleum additives and are well known for their antifungal and disinfectant properties. 3 Accordingly, the toxicological role of the latter group of compounds has the largest impact on aquatic organisms and, for instance in marine foodstuffs, a combination of all these amines can be encountered.All these amines are usually determined by chromatographic methods. However, these techniques are costly and not suitable for in situ sensing or rapid screening applications. An appealing alternative is the use of selective chromo-or fluorogenic chemosensors. 4 In fact the development of highly selective probes or indicators for small bio-molecules is still a barely studied field.One such advanced goal is the development of selective probes for real samples that would sense biogenic amines (first group, see above) via a simple chromo-fluorogenic test but would ideally remain silent in the presence of fatty amines (second group) and amino acids (another prominent source of amino moieties).To achieve this goal we focused our attention on pyrylium compounds. As we and others have shown previously, such heterocyclic ring systems react with amines to give the corresponding pyridinium derivatives. 5 Furthermore, pyrylium and the respective pyridinium salts are strong electron acceptors so that appropriate integration into a charge-transfer chromophore yields deeply coloured dyes that absorb and emit in the red spectral range. 6 The compounds P1-P7 (pyrylium dyes) and M1-M7 (methylpyridinium derivatives) (see Scheme 1) were prepared 7 and investigated t...

a b s t r a c tMicrosimulation is a useful tool to analyze traffic operation. On two-lane highways, the complexity of passing and the interaction with oncoming traffic requires specific models. This study focused on the development of a passing desire, decision and execution model. Results of the observation of 1752 maneuvers on 10 rural roads in Spain were used for this development. The model incorporated the effect of new factors such as available sight distance, delay and remaining travel time until the end of the highway segment. Outputs of the model were compared to observed data: firstly, individual passing maneuvers; secondly, traffic flow, percent followers and number of passing maneuvers in four single passing zones with two different traffic levels. The model was validated in four alternative passing zones.

ElsevierMoreno Chou, AT.; García García, A. (2013). Use of speed profile as surrogate measure: Effect of traffic calming devices on crosstown road safety performance. Accident Analysis and Prevention. 61:23-32. doi:10.1016/j.aap.2012.10 Submitted to Accident, Analysis and Prevention; SI: RSS 2011ABSTRACT Urban road safety management is usually characterized by a lack of quantity and quality of crash data and low budgets. However, fifty four percent of road crashes in Spain take place on urban areas. Moreover, ten percent of urban fatal crashes occur on crosstown roads, which are rural roads that traverse small communities. So, traffic calming measures (TCMs) are often implemented in this part of a rural road that traverses a small community in order to reduce both crash frequency and severity by lowering speeds.The objective of the research was to develop a methodology using continuous speed profile to evaluate safety effectiveness of TCMs on crosstown roads. Given the strong relationship between speed and crash experience, safety performance can be related to speed. Consequently, speed can be used indirectly as a surrogate safety measure.Two indexes were defined as surrogate safety measures based on the continuous speed profile: Ra and Ea. Ra represents absolute accumulated speed variations relative to the average speed, and is inversely related to accumulated speed uniformity; and Ea represents accumulated speed variations above the speed limit, and is directly related to accumulated speeding. Naturalistic data was collected using GPS trackers on twelve scenarios with different TCMs spacing. Then, the indexes were applied to individual observed speed profiles (individual analysis) as well as the operating speed profile (global analysis). The values obtained from individual and global analysis were statistically different. Spacing lower than 110 m, which was found optimal on previous research, did not allow drivers to modify their speeds as accumulated speed uniformity was quite similar regardless average operating speed; and, accumulated speeding was also minimized. Consequently, scenarios with implemented TCMs according to technical criteria presented a better design quality. On the other hand, age and gender differences didn't seem to affect average speed, nor accumulated speed uniformity or accumulated speeding.

Abstract:In this paper, we develop a synthetic population as the first step in implementing an integrated land use/transport model. The model is agent-based, where every household, person, dwelling, and job is treated as an individual object. Therefore, detailed socioeconomic and demographic attributes are required to support the model. The Iterative Proportional Updating (IPU) procedure is selected for the optimization phase. The original IPU algorithm has been improved to handle three geographical resolutions simultaneously with very little computational time. For the allocation phase, we use Monte Carlo sampling. We applied our approach to the greater Munich metropolitan area. Based on the available data in the control totals and microdata, we selected 47 attributes at the municipality level, 13 attributes at the county level, and 14 additional attributes at the borough level for the city of Munich. Attributes are aggregated at the household, dwelling, and person level. The algorithm is able to synthesize 4.5 million persons in 2.1 million households in less than 1.5 h. Directions regarding how to handle multiple geographical resolutions and how to balance the amount and order of attributes to avoid overfitting are presented.

Unbalanced flow patterns may be a problem in roundabouts, even at medium demand levels. One single approach can cause queues on the downstream approaches; the average delay can increase greatly, and the roundabout can fail. This operational problem can be lessened by regulating traffic with metering signals, one of the most cost-effective measures used in Australia, the United Kingdom, and the United States. Even though some Spanish roundabouts exceed capacity, the potential benefit to local conditions has not been studied. Traffic microsimulation was used to analyze capacity improvements and operational performance on roundabouts with metering signals. A field study characterized gap acceptance behavior on conditions close to capacity. Vissim was calibrated and validated, and a signal control logic was implemented in its VisVAP module. The capacity from traffic microsimulation represents the traffic demands observed in the field more accurately because of the variable follow-up headways. In contrast, the U.S. Highway Capacity Manual 2010 underestimates capacity for almost all observed conditions. Almost 400 combinations of design and control parameters for metering signals were required to obtain the optimal (location and timing) model with the lowest average delay. Then, traffic demand scenarios were varied with the optimal metering system. The percentage benefit, calculated as overall average delay, could be up to 60% depending on the combination of controlling traffic demand and conflicting traffic flow. Results allow users to determine the need for metering and quantify the potential benefit from its application to one-lane roundabouts.