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Stream speed pattern of traffic plays a crucial role in urban transportation. The presence of on-street parking significantly reduces this speed by narrowing the carriageway width available for traffic movement, impeding the traffic flow. Therefore, understanding the traffic flow behavior in the context of on-street parking could be challenging. In this context, the present study explores the influence of on-street parking on the stream speed of regular traffic. To achieve this, data were collected at various ideal and parking sections. The stream speed ranges from 39.28 km/h to 51.47 km/h for ideal sections with significant percentage reduction observed at parking sections, ranging from 39.09% to 81.30%. This speed reduction was then modelled considering the most significant parking parameters conceptualized in this study. The findings of the study offer valuable insights that can be implemented for developing the on-street parking norms. [ABSTRACT FROM AUTHOR]

Information on lateral placement and lane indiscipline is useful in simulation of a mixed traffic stream and in identifying the distressed portion of a pavement. Despite this utility, inadequate investigation has been made to estimate the lateral placement of vehicles under prevailing traffic conditions. In a typical mixed traffic situation, vehicles having different static and dynamic characteristics take any lateral gap across the carriageway left empty by other surrounding vehicles and move in an untidy manner. This leads to variation in lateral placement of vehicles, governed by the subject vehicle type. This paper explores the potential factors that influence lateral placement of vehicles and presents an artificial neural network (ANN)-based approach to quantify lateral placement and lane indiscipline in the context of undivided urban roads. Further, sensitivity analysis revealed how different traffic parameters like traffic volume, traffic composition, and directional split influence lateral placement and lane indiscipline within each vehicle category. Key words: lateral placement, lane indiscipline, traffic volume, traffic composition, directional split. L'information sur le placement lateral et l'indiscipline de voie est utile pour simuler un flux de circulation mixte et identifier la partie usee d'une chaussee. Malgre ces informations utiles, il y a un manque de recherche effectuee pour estimer le placement lateral des vehicules dans les conditions de circulation qui prevalent. Dans une situation de circulation mixte typique, les vehicules ayant des caracteristiques statiques et dynamiques differentes prennent tout espace lateral sur la chaussee laisse libre par d'autres vehicules environnants et se deplacent de maniere desordonnee. Cette situation entraine des variations dans le placement lateral des vehicules regis par le type de vehicule. Cet article explore les facteurs potentiels qui influent sur le placement lateral des vehicules et presente une approche fondee sur les reseaux de neurones artificiels pour quantifier le placement lateral et l'indiscipline de voie dans le contexte de routes urbaines indivises. De plus, une analyse de sensibilite a revele comment differents parametres de circulation, comme le volume de circulation, la composition de la circulation et la division directionnelle, influent sur le placement lateral et l'indiscipline de voie d'une categorie de vehicules. [Traduit par la Redaction] Mots-cles : placement lateral, indiscipline de voie, volume de circulation, composition de la circulation, division directionnelle., Introduction Lateral placement (LP) represents the transverse position of a vehicle on a carriageway. For an undivided road, LP is measured as the distance from the left edge of the [...]

Developing countries are facing challenges in sustaining urban traffic congestion due to rapid urbanization. To manage urban traffic, a traffic engineer first needs to assess the current operational condition on urban roads. Level of service (LOS) is used to define the operational traffic condition within a traffic stream in terms of service quality that a facility is providing to its user. This paper proposes a novel approach to estimate 'speed ratio' by considering individual free-flow speed (FFS) of different vehicle categories. This study also provides a comparison between FFS estimated using the methods given in Highway Capacity Manual 2010 and Indian-Highway Capacity Manual 2018. LOS criteria were developed using five clustering technique: K-means, K-medoids, Clustering Large Applications, Fuzzy-C Means, and Hierarchical Agglomerative Clustering. Both internal and external cluster validation indices were used to find the optimal number of clusters and suitable clustering algorithms. Key words: level of service, speed ratio, clustering algorithms, undivided urban road, performance measures, free-flow speed. Les pays en developpement font face a des defis de gestion de la congestion routiere urbaine en raison de l'urbanisation rapide. Afin de gerer la circulation urbaine, un ingenieur de la circulation doit d'abord evaluer l'etat actuel de l'exploitation des routes urbaines. On emploie le terme << niveau de service >> pour definir l'etat de l'exploitation de la circulation dans un courant de circulation en termes de qualite de service qu'une installation fournit a son utilisateur. Le present document propose une approche novatrice pour estimer le << rapport de vitesse >> en tenant compte de la vitesse de croisiere (VC) individuelle de differentes categories de vehicules. Cette etude fournit egalement une comparaison entre les estimations de VC a l'aide des methodes donnees dans le Highway Capacity Manual de 2010 et le Indian-Highway Capacity Manual de 2018. Les criteres du niveau de service ont ete developpes en utilisant cinq techniques d'agregation : << K-means >>, << K-medoids >>, << clustering large applications >>, << fuzzy-C means >> et agregation ascendante hierarchique. Des indices de validation des grappes internes et externes ont ete utilises pour trouver le nombre optimal de grappes et des algorithmes de groupement appropries. [Traduit par la Redaction] Mots-cles: niveau de service, rapport de vitesse, algorithmes de groupement, route urbaine a chaussee unique, mesures du rendement, vitesse de croisiere., 1. Introduction Most of the developing countries are facing difficulties in managing traffic congestion on urban roads due to the rapid pace of urbanization. According to the 2001 Indian census, [...]

Horizontal curves on undivided hilly roads are critical segments prone to head-on crashes between opposite-direction-bound vehicles. The majority of head-on crashes occur due to the inability of drivers to keep their vehicles at right lateral placements across the carriageway when maneuvering on these curves. The traffic safety assessment at horizontal curves conducted in past studies was largely based on previous crash records. However, there is a complete absence of a proximal indicator quantifying the crash potential of a horizontal curve, unlike other critical road segments. As background, this paper conceptualizes Mutual Area in Lateral Distribution (MALD) as a proximal indicator for head-on crash potential at horizontal curves and demonstrates an effective methodology for its field estimation. Theoretically, MALD may vary within a range of [0–1] with a higher value indicating a higher head-on crash potential. Further, a validation test was performed where the proposed methodology was implemented to determine the MALD of seven distinct horizontal curves. The results justified the effectiveness of MALD as a proximal indicator of head-on crash potential. [ABSTRACT FROM AUTHOR]

Majority of the existing studies on passenger car unit (PCU) estimation are limited to inter-urban and divided urban roads. The characteristics of traffic on undivided urban roads are completely different from those on divided roads. This study aims to estimate the PCU values on undivided urban roads with varying traffic conditions. Estimation of PCU requires speed information for individual vehicle categories. Hence, a universal Kriging-based speed prediction model was developed and utilized for PCU estimation. The model was constructed based on the classified traffic volume and speed data that were collected by videography method on undivided urban road segments in different cities in India. The proposed model was utilized to study the effects of traffic volume, traffic composition, and carriageway width on PCU. An alternative approach of 'Stream Equivalency Factor' has also been suggested in this paper. Use of this approach can simplify the process of determining the homogeneous equivalent of a mixed traffic flow. [ABSTRACT FROM AUTHOR]

A significant fraction of eukaryotic proteins contain low-complexity sequence elements with unknown functions. Many of these sequences are prone to form biomolecular condensates with unique material and dynamic properties. Mutations in low-complexity regions often result in abnormal phase transitions into pathological solid-like states. Therefore, understanding how the low-complexity sequence patterns encode the material properties of condensates is crucial for uncovering the cellular functions and evolutionary forces behind the emergence of low-complexity regions in proteins. In this work, we employ an alphabet-free energy landscape framework of the stickers and spacers to dissect how the low complexity patterns of proteins encode the material properties of condensates. We find a broad phase diagram of material properties determined by distinct energy landscape features, showing that periodic repeat motifs promote elastic-dominated while random sequences are viscous-dominated properties. We find that a certain degree of sticker periodicity is necessary to maintain the fluidity of condensates, preventing them from forming glassy or solid-like states. Finally, we show that the energy landscape framework captures viscoelastic trends seen in the recent experiments on prion domains and makes predictions for systematic variation of protein condensate viscoelasticity via altering the periodicity and strength of sticker motifs.