Slow Cars Research Articles

Achieving realistic cyclist behavior in SUMO using the SimRa dataset

Increasing the modal share of bicycle traffic to reduce carbon emissions, reduce urban car traffic, and to improve the health of citizens, requires a shift away from car-centric city planning. For this, traffic planners often rely on simulation tools such as SUMO which allow them to study the effects of construction changes before implementing them. Similarly, studies of vulnerable road users, here cyclists, also use such models to assess the performance of communication-based road traffic safety systems. The cyclist model in SUMO, however, is very imprecise as SUMO cyclists behave either like slow cars or fast pedestrians, thus, casting doubt on simulation results for bicycle traffic. In this paper, we analyze acceleration, deceleration, velocity, and intersection left-turn behavior of cyclists in a large dataset of real world cycle tracks. We use the results to improve the existing cyclist model in SUMO and add three more detailed cyclist models and implement them in SUMO.

Abstract 1148: 1XX mutations slow CAR T cell signaling and increase in vivo persistence

Abstract Purpose: Develop CAR T cells that have increased persistence in vivo and kill low antigen expressing solid tumor cancer cells. Experimental: Three CARs were generated that were all targeted to the tumor with the same antibody fragment, huMNC2, that recognizes a cryptic epitope on the MUC1 cleavage product called MUC1* (muk 1 star). One construct comprises a 41BB co-stimulatory domain, while the second construct has a CD28 co-stimulatory domain. The first 2 CARs have a wild-type CD3z, whereas the 3rd bears Michel Sadelain’s “1XX” mutations in CD3z. These are 2 Tyrosine to Phenylalanine mutations in ITAM 2 and ITAM 3. The 1XX mutations were designed to slow signaling to eliminate the problem of CAR T cell exhaustion. Human T cells were separately transduced with the 3 CARs and tested in NSG mice bearing human breast tumors. The tumors were heterogeneous tumors comprising parent cells that fluoresce red and express medium to low amounts of the antigen, MUC1*, and cells that fluoresce green wherein the parent cells have been transduced to express more MUC1*. The percent of the tumor that expressed high levels of MUC1* was varied from 7.5% to 15% to 30%. 150 female NSG mice were implanted with 500,000 tumor cells. The animals received a single CAR T cell injection of one of the three CAR T cells at an Effector to Target ratio of 10:1, 5:1, or 1:1. The experiment was allowed to proceed for 96 days, with periodic IVIS measurements to track tumor growth with a focus on tumor recurrence. After sacrifice, residual tumors were excised, dissociated and analyzed to determine if tumor recurrence was being driven by the high antigen cells or the low antigen cells. CAR T cells were recovered from the blood and the spleen. They were enumerated and analyzed by flow cytometry for the presence of markers of exhaustion. Unpublished Results: Tumor recurrence occurred in mice treated with CAR T cells bearing wild-type CD3z, but essentially did not recur in the mice treated with CAR T cells bearing the 1XX mutations. Four hundredfold more CAR T cells were recovered from the mice treated with the CAR-1XX cells compared to CARs with wild-type CD3z, and the CAR-1XX cells appeared not to be exhausted even after 96 days. CAR-1XX T cells administered at a 1:1 E:T ratio, with only 7.5% of the tumor comprised of high antigen expressing cells, were effectively killed with no significant tumor recurrence. In contrast, the CARs with wild-type CD3z had no effect on tumor growth in this group. Surprisingly, analysis of excised tumors showed that tumor recurrence in mice treated with CAR wild-type CD3z T cells was driven by the low antigen density cells, whereas the CAR-1XX T cells killed high antigen and low antigen density cells at the same rate. Conclusions: 1XX mutations in CD3z greatly increase CAR T persistence in vivo and unexpectedly enable the killing of low antigen tumor cells. Citation Format: Cynthia C. Bamdad, Benoit J. Smagghe, Mark G. Carter, Danica M. Walkley, Jac-Leen S. Nash, Kevin R. Yi, Trevor J. Grant, Laura M. Reale, Michael J. Nash, Gregory L. Riley, Andrew K. Stewart. 1XX mutations slow CAR T cell signaling and increase in vivo persistence [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1148.

Inequality Without Efficient Redistribution: The Fed, Populism, Central Banks and Slow Car Crashes: Unlimited Credit Produces Unlimited Debt

Inequality Without Efficient Redistribution: The Fed, Populism, Central Banks and Slow Car Crashes: Unlimited Credit Produces Unlimited Debt

ПОТОКИ БАРТЛЕТТА И МАТЕМАТИЧЕСКОЕ ОПИСАНИЕ АВТОТРАНСПОРТНЫХ ПОТОКОВ

Introduction: The class of mathematical traffic models is based on the theory of queuing. In these models, the application entering the service system corresponds to the vehicle. When developing a traffic model formulated in terms of queuing, it is necessary to specify a random flow that is incoming to the queuing system. The purpose of the study: Traditional queuing systems with recurrent incoming flow under appropriate conditions do not reflect the specific features of real traffic flows. Under certain conditions, for example, it may be appropriate to use a Markov-type flow in the model, the intensity of which depends on the state of a mathematical object called the control device. In the general case, such a flow can be specified as non-uniform, and with such a task, each request is assigned a type that also depends on the state of the control device. Setting the qualitative structure and parameters of a random flow depends on the assessment of the speed characteristics of the vehicles that form the flow, and, therefore, is related to the issues of studying the speed characteristics of real vehicles. Practical significance: At a sufficiently low density of the traffic flow, the incoming flow is close to the Poisson one. As traffic increases and road conditions worsen, the risk of overtaking increases and clusters are formed, consisting of a slow car moving in front and a group of fast cars that cannot overtake a slow one. In such cases, we can assume that the incoming flow is a Bartlett flow, which has the following form: clusters form a Poisson flow, and the cluster length distribution is a two-parameter Bartlett distribution. One of the parameters of this distribution is the probability of having a group of fast cars, and the second parameter characterizes the distribution of the number of cars in this group. Discussion: In this paper, we study the questions of setting a qualitative probabilistic structure and quantitative parameters of random flows, which are elements of queuing systems used as traffic models.

Traffic States and Jamming Transitions Induced by a Slow Car in Two-lane Traffic Flow

We investigate the traffic states transition and jamming induced by a slow car in two-lane traffic of cars by using a generalized optimal velocity model, which is based on the optimal velocity model. We obtain the relationship between current and density under the circumstance when a slow car was introduced into the original high speed moving highway where cars change lanes frequently. It is found that the entire density space is divided to four distinct area, symbolizing different traffic states. The spatiotemporal diagram of each state is presented. Through the diagram, the evolution and development of traffic flow, jamming as well, is demonstrated.

Origins of Reverse Lane Usage Using Nagel–Schreckenberg Model

On highways with two lanes, cars are requested to run on the slow lane and are allowed to run on the fast lane for overtaking. However, on real two-lane highways, we daily observe a phenomenon called "reverse lane usage", in which the flow on the fast lane exceeds that on the slow lane. The origins of the phenomenon have not been discussed clearly. In this paper, we study a two-lane extension of the Nagel-Schreckenberg model. We employ two types of lane-changing rules: a German and a Japanese type. The German type suppresses overtaking slow cars on the fast lane through the slow lane. The Japanese type, on the contrary, allows overtaking through both lanes. If two lanes allow the same maximum speed, the suppression of overtaking through the slow lane is the key for the reverse lane usage. If the maximum speed on the fast lane is faster than that on the slow lane, the reverse lane usage is observed in the Japanese type. The effects of stochasticity in lane changing, and mixing trucks and passenger cars are also discussed.

The smart road not taken [Tech History

On a cool December day in 1925, Charles Adler Jr. stood beside Falls Road, a state highway on Baltimore's north side. He was there to test his latest invention: an electromagnetic apparatus that would automatically slow cars traveling at unsafe speeds. Adler had embedded magnetic plates in the road where it led into a precarious curve, and he was now waiting for a specially prepared car to drive over the magnets. The magnets would activate a speed governor connected to the vehicle's engine, slowing it to 24 kilometers per hour.

Emotional states of drivers and the impact on speed, acceleration and traffic violations—A simulator study

Maladjusted driving, such as aggressive driving and delayed reactions, is seen as one cause of traffic accidents. Such behavioural patterns could be influenced by strong emotions in the driver. The causes of emotions in traffic are divided into two distinct classes: personal factors and properties of the specific driving situation. In traffic situations, various appraisal factors are responsible for the nature and intensity of experienced emotions. These include whether another driver was accountable, whether goals were blocked and whether progress and safety were affected. In a simulator study, seventy-nine participants took part in four traffic situations which each elicited a different emotion. Each situation had critical elements (e.g. slow car, obstacle on the street) based on combinations of the appraisal factors. Driving parameters such as velocity, acceleration, and speeding, together with the experienced emotions, were recorded. Results indicate that anger leads to stronger acceleration and higher speeds even for 2km beyond the emotion-eliciting event. Anxiety and contempt yielded similar but weaker effects, yet showed the same negative and dangerous driving pattern as anger. Fright correlated with stronger braking momentum and lower speeds directly after the critical event.

Venue-based Mobility Models: Evaluation of MANET Routing Protocols

is infrastructure less network consisting of wireless nodes acting either as a host or a routing node. A number of simulation studies have been carried out to evaluate the performance of MANET routing protocols. In typical simulations, nodes move at speeds between the broad range of 1 - 30 m/s, whereas in a real life setting, the movement speed of nodes at a particular venue may be confined to a narrower range depending on the nature of the venue. This paper analyzes the performance of routing protocols, on the basis of four venue based mobility models. These models are Fast Car Model (FCM), Slow Car Model (SCM), Human Run Model (HRM) and Human Walk Model (HWM). Four routing protocols namely AODV, DSDV, DSR and TORA are compared in this paper. The simulation results show that DSDV has low end-to-end delay, whereas TORA has high overhead as speed is increased.

What will be the real cost of the ‘bedroom tax’?

The repellent ‘bedroom tax’ – reducing benefits paid to those who are deemed to have more bedrooms than they need – is a slow car crash of a policy.

Velocity and cluster distributions in a bottleneck system

Velocity and cluster distributions for particles with unidirectional motion in one dimension are studied. The particles never pass each other, like cars on a narrow road that does not allow overtaking. As a result, particles cluster behind slow particles (queues are formed behind slow cars). Thus, the actual velocity of each particle is to a large extent determined by slow particles further ahead. Considering all possible permutations of N particles with initial velocities {vi}, the average number of particles with actual velocity vi is (N+1)/[i(i+1)] (in the sequence {vi}, the initial velocities are listed with monotonically increasing values). For i large and vi proportional, variant i the average number of actual velocities is thus a power law in vi, even though the average cluster density is found to be independent of cluster size, L. On the other hand, the cluster density varies significantly with cluster velocity; we obtain [(N-i)!(N-L)!]/[NN!(N-L-i+1)!]. The average velocity at a given position in the sequence of N particles, and the average global velocity are determined. Explicit results for several distributions of the initial velocities show that the global velocity depends sensitively on the form of this distribution.

Disorder effect on the traffic flow behavior

The effects of some disorders, on the traffic flow behavior, are studied numerically. Especially, the effect of mixture of vehicles of different velocities and/or lengths, the effects of different drivers reactions, the position and the extraction rate of off-ramp in the free way. Using a generalized optimal velocity model, for a mixture of fast and slow vehicles, we have investigated the effect of delay times τ f and τ s on the fundamental diagram. It is Found that the small delay times have almost no effect, while, for sufficiently large delay time τ s , the current profile displays qualitatively five different forms, depending on τ f , τ s and the fractions f f and f s of the fast and slow cars, respectively. The velocity (current) exhibits first-order transitions at low and/or high densities, from freely moving phase to the congested state, and from congested state to a jamming one, respectively. The minimal current appears in intermediate values of τ s . Furthermore there exist, a critical value of τ f above which the meta-stability and hysteresis appear. The effects of disorder due to drivers behaviors have been introduced through a random delay time τ allowing the car to reach its optimal velocity traffic flow models with open boundaries. In the absence of the variation of the delay time Δτ, it is found that the transition from unstable to meta-stable and from meta-stable to stable state occur under the effect of the injecting and the extracting rate probabilities α and β respectively. Moreover, the perturbation of the traffic flow behavior due to the off-ramp has been studied using numerical simulations in the one dimensional cellular automaton traffic flow model with open boundaries. When the off-ramp is located between two critical positions i c1 and i c2 the current remains constant (plateau) for β0c1 < β0 < β0c2, and the density undergoes two successive first order transitions: from high density to plateau current phase and from average density to the low one. In the case of two off-ramps, these transitions occur only when the distance between ramps, is smaller than a critical value.

THE EFFECT OF DELAY TIMES ON THE OPTIMAL VELOCITY TRAFFIC FLOW BEHAVIOR

We have numerically investigated the effect of the delay times τf and τs of a mixture of fast and slow vehicles on the fundamental diagram (the current-density relation) of the optimal velocity model. The optimal velocity function of the fast cars depends not only on the headway of each car but also on the headway of the immediately preceding one. It is found that the small delay times have almost no effects, while, for sufficiently large delay time τs, the current profile displays qualitatively five different forms, depending on τf, τs and the fractions df and ds of the fast and slow cars, respectively. The velocity (current) exhibits first-order transitions at low and/or high densities, from freely moving phase to the congested state, and from congested state to a jamming one, respectively. The minimal current appears in intermediate values of τs. Furthermore, there exist a critical value of τf above which the metastability and hysteresis appear. The spatial-temporal traffic patterns near the congested-jamming first-order transition is also presented.

A cellular automaton model for mixing traffic in two-lane system

Based on the Nagel-Schrekenberg(NS) model,we present a mixing traffic flow model for a two-lane traffic system. In this model,the stochastic noise P in NS model is replaced by accelerating probability Pa and braking probabil ity Pd. The fundamental diagrams of the mixing traffic under differen t conditi ons are given by the numerical simulations. We found that the lane-changing prob ability,the mixing rate and acceleration, the braking probability have a great i nfluence on the mixing traffic flow. The slow cars have a decisive action on the mixing traffic.

Traffic states and jamming transitions induced by a bus in two-lane traffic flow

We study the traffic states and jamming transitions induced by a bus (slow car) in a two-lane traffic of cars. We use the dynamic model which is an extended one of the optimal velocity model to take into account the lane changing. The fundamental (flow-density) diagram is presented. The fundamental diagram changes highly by introducing a bus on a two-lane roadway. It is found that there are the six distinct states for the two-lane traffic flow including a bus. The spatio-temporal patterns are presented for the distinct traffic states. The dynamical state of traffic changes with density of cars. It is shown that the dynamical transitions among the distinct traffic states occur at some values of density. The phase diagram (region map) is shown for the two-lane traffic flow including a bus.

A REALISTIC TWO-LANE CELLULAR AUTOMATON MODEL FOR TRAFFIC FLOW

This paper extends a recently proposed single-lane cellular automaton model [Li et al., Phys. Rev. E64, 066128 (2001)], which considers the velocity effect of the preceding car, to two-lane traffic system. The traffic behaviors in both homogeneous system and inhomogeneous system are investigated. For homogeneous traffic, it is shown that the velocity effect enhances the maximum flux but does not change the qualitative properties of the fundamental diagram. Nevertheless, the qualitative changes of the lane changing frequency and congested pattern occur. In the inhomogeneous system, the honk effect is studied. It is found that the honk effect first strengthens then weakens with the increase of R, the ratio of slow cars to all cars.

Harmaat aallot. Ympäristönsuojelun tulo Suomeen by Simo Laakkonen Sari Laurila Marjatta Rahikainen (review)

584 SEER, 79, 3, 2001 were coopted into governmental positions, leaving a vacuum in the non-state domain of activism. A more Machiavellian story is told by Sonja Boehmer-Christiansen,who argues that West Germans grossly exaggerated the GDR's environmental travailsin order to providejustificationfor shuttingdown existing industryin the East and replacingit with colonial economic investments.Whateverdirty industrythere was, according to the author,was the resultof the initialstages of industrializationin easternGermanyand dependence on lignite,producing effectsnot dissimilarto conditions in the Ruhr or in Manchesterof an earlier period. Positive achievements, such as small and slow cars, household waste recycling, large areas of quiet forestsand lakes, and lack of disposableplastic packaging,have been ignoredby Westerncritics. Certainly,the extreme anti-Communistviews are unbalanced,yet many of the positive featuresBoehmer-Christiansenlistswere more the product of an inefficient, capital-starved economy unable to innovate than of conscious environmental sensitivity. Ultimately, one of the unifyingelements of thiscollection is itsmessagethat the Cold Warcontext caused problemsand theirsolutionsto be posed as a set of unproductivebinarychoices: communism or capitalism,'dirty'communist industry(in the former GDR) or 'clean' de-industrialization,and so on. The editorscall fora Third Way. 'The futureofpoliticalecology lies in constituting a systemic challenge to both free marketorthodoxy and the now discredited centralplanning of ex-actual socialism'(p. 25). In a rich concluding section Tickle and Welsh ponder why the environmental movements of EasternEurope,which had played such unprecedented political roles and which had held aloft the banner of a humane and socially responsive modernity, faded so quickly. Larger exogenous trends, such as globalization and Westernlending policies, they offer,helped to suffocateany incipient social democracy, while at the same time amplifying existing local traditions of patriarchy, civic passivity, and nationalism. The cooption of movement leaders finished the process. The editors are to be congratulated for assemblingthistimely and critical-mindedcollection. Department ofHistory DOUGLAS R. WEINER University ofArizona Laakkonen, Simo; Laurila, Sari, and Rahikainen, Marjatta (eds). Harmaat aallot. rmpdristdnsuojelun tuloSuomeen.Historiallinen Arkisto, I I3. Suomen Historiallinen Seura, Helsinki, 1999. 236 pp. Notes. Bibliography. Price unknown. THE history of environmental problems has only recently been taken up in Finland. One of the projects that has been launched, with funding from the Finnish Academy and the communities involved, is a collaborative, multidisciplinary research exercise investigating the water policies of eight of Finland's largest urban centres. This volume contains parts of the results from six of them. It claims to be a pioneering study in the field of environmental history. The papers collected here are the work of ten separate contributors, REVIEWS 585 but most of the contents are essentially focused on the same questions. The basic subjectmatter is water and sewage, which became problems in Finland forthe firsttime in the nineteenth centurywith the beginningsof urbanization and industrialization. Previous to that period, Finns had been a tiny population inhabitinga largecountry,and living in small,scatteredfarmsand villages. Their water came fromwells, or the nearestlake or stream,and their environment was spacious enough for the disposal of waste to present no problems. They had lived that way for centuries. The research in this study shows how, when such people congregated in towns, they showed little consciousness that water supply or sewage disposal could be a problem and carriedon in the traditionalway. Drinking water came from wells, the waste went into open drains, accumulated solids were removed by horse and cart and in both cases ended up in the nearest convenient open water. The result was cumulative pollution of wells and surface water sources, and chronic outbreaksof water-borne infections such as cholera and typhoid. The effect was compounded since the same waters used for disposal and sewage were also used for bathing and laundering. Further early industrial enterprises assumed as a matter of course a right to feed their effluents into the same water sources. A law of I879 required urban communities to employ their own medical officersand set up Health Boards,and environmentalawareness developed in Finlandthroughtheirwork. By the i88os, recent medical discoveries about bacteria, and how their presence in waterwas linkedto pollution of the water suppliesand the spread of disease were known in Finland as were the techniques available for providing a reliable supply of clean water and, from the i89os they were...

Phase transition in a traffic model with passing

We investigate a traffic model in which cars either move freely with quenched intrinsic velocities or belong to clusters formed behind slower cars. In each cluster, the next-to-leading car is allowed to pass and resume free motion. The model undergoes a phase transition from a disordered phase for the high passing rate to a jammed phase for the low rate. In the disordered phase, the cluster size distribution decays exponentially in the large size limit. In the jammed phase, the distribution of finite clusters is independent on the passing rate, but it accounts only for a fraction of all cars; the "excessive" cars form an infinite cluster moving with the smallest velocity. Mean-field equations, describing the model in the framework of Maxwell approximation, correctly predict the existence of phase transition and adequately describe the disordered phase; properties of the jammed phase are studied numerically.

Reaction-diffusion models describing a two-lane traffic flow

A unidirectional two-lane road is approximated by a set of two parallel closed one-dimensional chains. Two types of cars, i.e., slow and fast ones are considered in the system. Based on the Nagel-Schreckenberg model of traffic flow [K. Nagel and M. Schreckenberg, J. Phys. 2, 2221 (1992)], a set of reaction-diffusion processes is introduced to simulate the behavior of the cars. Fast cars can pass the slow ones using the passing lane. We write and solve the mean-field rate equations for the density of slow and fast cars, respectively. We also investigate the properties of the model through computer simulations and obtain the fundamental diagrams. A comparison between our results and the v(max)=2 version of the Nagel-Schreckenberg model is made.

Disorder effects in cellular automata for two-lane traffic

For single-lane traffic models it is well known that particle disorder leads to platoon formation at low densities. Here we discuss the effect of slow cars in two-lane systems. Surprisingly, even a small number of slow cars can initiate the formation of platoons at low densities. The robustness of this phenomenon is investigated for different variants of the lane-changing rules as well as for different variants on the single-lane dynamics. It is shown that anticipation of drivers reduces the influence of slow cars drastically.