A verification method for identifying critical segments considering highly correlated characteristics of traffic flow

2020 ◽  
Vol 31 (03) ◽  
pp. 2050048
Author(s):  
Zundong Zhang ◽  
Mengyao Zhu ◽  
Jeff Ban ◽  
Yifan Zhang

Since critical segments on a transportation network vary over time and are determined by the nature of traffic systems, the identification of critical segments is the basis for realizing area-wide traffic coordination control and regional traffic state optimization. For decades, the identification of critical segments of dynamic traffic flow networks has attracted wide attention. In recent years, some important advances have been made in the related research on the identification of critical segments using the theory of percolation which validates the impact of critical segments by increasing the speed value of critical segments. However, most of them failed to take into account highly correlated characteristics between adjacent segments, which causes identification results cannot be validated effectively and efficiently. In this paper, we improve the existing critical segments identification methods by considering the highly correlated characteristics. A verification method based on ego-networks is proposed that improves the ego-networks speed of critical segments to verify the accuracy of identification results. The experiment shows the method can verify the validity of critical segments recognition results more accurately.

2020 ◽  
Vol 12 (14) ◽  
pp. 5596 ◽  
Author(s):  
Yanmin Qi ◽  
Zuduo Zheng ◽  
Dongyao Jia

The impact of inclement weather on traffic flow has been extensively studied in the literature. However, little research has unveiled how local weather conditions affect real-time traffic flows both spatially and temporally. By analysing the real-time traffic flow data of Traffic Signal Controllers (TSCs) and weather information in Brisbane, Australia, this paper aims to explore weather’s impact on traffic flow, more specifically, rainfall’s impact on traffic flow. A suite of analytic methods has been applied, including the space-time cube, time-series clustering, and regression models at three different levels (i.e., comprehensive, location-specific, and aggregate). Our results reveal that rainfall would induce a change of the traffic flow temporally (on weekdays, Saturday, and Sunday and at various periods on each day) and spatially (in the transportation network). Particularly, our results consistently show that the traffic flow would increase on wet days, especially on weekdays, and that the urban inner space, such as the central business district (CBD), is more likely to be impacted by inclement weather compared with other suburbs. Such results could be used by traffic operators to better manage traffic in response to rainfall. The findings could also help transport planners and policy analysts to identify the key transport corridors that are most susceptible to traffic shifts in different weather conditions and establish more weather-resilient transport infrastructures accordingly.


Diagnosis ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Justin B. Searns ◽  
Manon C. Williams ◽  
Christine E. MacBrayne ◽  
Ann L. Wirtz ◽  
Jan E. Leonard ◽  
...  

AbstractObjectivesFew studies describe the impact of antimicrobial stewardship programs (ASPs) on recognizing and preventing diagnostic errors. Handshake stewardship (HS-ASP) is a novel ASP model that prospectively reviews hospital-wide antimicrobial usage with recommendations made in person to treatment teams. The purpose of this study was to determine if HS-ASP could identify and intervene on potential diagnostic errors for children hospitalized at a quaternary care children’s hospital.MethodsPreviously self-identified “Great Catch” (GC) interventions by the Children’s Hospital Colorado HS-ASP team from 10/2014 through 5/2018 were retrospectively reviewed. Each GC was categorized based on the types of recommendations from HS-ASP, including if any diagnostic recommendations were made to the treatment team. Each GC was independently scored using the “Safer Dx Instrument” to determine presence of diagnostic error based on a previously determined cut-off score of ≤1.50. Interrater reliability for the instrument was measured using a randomized subset of one third of GCs.ResultsDuring the study period, there were 162 GC interventions. Of these, 65 (40%) included diagnostic recommendations by HS-ASP and 19 (12%) had a Safer Dx Score of ≤1.50, (Κ=0.44; moderate agreement). Of those GCs associated with diagnostic errors, the HS-ASP team made a diagnostic recommendation to the primary treatment team 95% of the time.ConclusionsHandshake stewardship has the potential to identify and intervene on diagnostic errors for hospitalized children.


2021 ◽  
Vol 3 (8) ◽  
Author(s):  
Ting Liu ◽  
Gabriel Lodewijks

Abstract Abstract On the basis of the influence of dry season on ship traffic flow, the gathering and dissipating process of ship traffic flow was researched with Greenshields linear flow—density relationship model, the intrinsic relationship between the ship traffic congestion state and traffic wave in the unclosed restricted channel segment was emphatically explored when the ship traffic flow in a tributary channel inflows, and the influence law of multiple traffic waves on the ship traffic flow characteristics in unclosed restricted segment is revealed. On this basis, the expressions of traffic wave speed and direction, dissipation time of queued ships and the number of ships affected were provided, and combined with Monte Carlo method, the ship traffic flow simulation model in the restricted channel segment was built. The simulation results show that in closed restricted channel segment the dissipation time of ships queued is mainly related to the ship traffic flow rate of segments A and C, and the total number of ships affected to the ship traffic flow rate of segment A. And in unclosed restricted channel segment, the dissipation time and the total number of ships affected are also determined by the meeting time of the traffic waves in addition to the ship traffic flow rate of segments. The research results can provide the theoretical support for further studying the ship traffic flow in unclosed restricted channel segment with multiple tributaries Article Highlights The inflow of tributaries' ship traffic flows has an obvious impact on the traffic conditions in the unenclosed restricted channel segment. The interaction and influence between multiple ship traffic waves and the mechanism of generating new traffic waves are explained. The expression of both dissipation time of queued ships and the total number of ships affected in the closed and unclosed restricted channel segment are given.


Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 585
Author(s):  
Catalina Iticescu ◽  
Puiu-Lucian Georgescu ◽  
Maxim Arseni ◽  
Adrian Rosu ◽  
Mihaela Timofti ◽  
...  

The use of sewage sludge in agriculture decreases the pressure on landfills. In Romania, massive investments have been made in wastewater treatment stations, which have resulted in the accumulation of important quantities of sewage sludge. The presence of these sewage sludges coincides with large areas of degraded agricultural land. The aim of the present article is to identify the best technological combinations meant to solve these problems simultaneously. Adapting the quality and parameters of the sludge to the specificity of the land solves the possible compatibility problems, thus reducing the impact on the environment. The physico-chemical characteristics of the fermented sludge were monitored and optimal solutions for their treatment were suggested so as to allow that the sludge could be used in agriculture according to the characteristics of the soils. The content of heavy metals in the sewage sludge was closely monitored because the use of sewage sludge as a fertilizer does not allow for any increases in the concentrations of these in soils. The article identifies those agricultural areas which are suitable for the use of sludge, as well as ways of correcting some parameters (e.g., pH), which allow the improvement of soil quality and obtained higher agricultural production.


2021 ◽  
Vol 11 (14) ◽  
pp. 6537
Author(s):  
Marian Łupieżowiec

The article presents the concept of monitoring buildings and infrastructure elements located near large construction investments (the construction of high-rise buildings of the Oak Terraces housing estate in Katowice and the construction of a tunnel under the roundabout in Katowice along the intercity express road DTŚ). The impacts include deep excavation, lowering of the groundwater level over a large area, and dynamic influences related to the use of impact methods of soil improvement. The presented monitoring includes observation of the groundwater level with the use of piezometers, geodetic measurements of settlement and inclinations, as well as the measurement of vibration amplitudes generated during the works involving shocks and vibrations. It was also important to observe the development of cracks on the basis of a previously made inventory of damage. The results of the monitoring allow corrections to be made in the technology of works (e.g., reduction of vibration amplitudes, application of additional protections at excavations, etc.) or the use additional safety measures. Currently, there are also monitoring systems used during the operation of completed facilities.


2016 ◽  
Vol 12 (12) ◽  
pp. 188
Author(s):  
Nguyen N.T. Vo

This paper evaluates the impact of trading locations on equity returns by examining the stock price behaviour of three Anglo-Dutch dual-listed companies which result from mergers where two corporations agree to function as a single operating business, but maintain separate identities. The shares of these stocks are traded not only in their home market but also on several US stock exchanges in the form of American Depository Receipts. Regressing the return differentials on these dual-listed and cross-listed stocks on the relative market index returns and currency changes provides evidence of an apparent violation of the Law of One Price. The regression results show that the return on each part of dual-listed companies is highly correlated with the market on which it is most intensively traded. Similarly, returns on cross-listed stocks have considerably higher co-movement with US market indices and considerably lower co-movement with home-market indices than their home-market counterparts. Market risk premium is not a significant explanatory variable of the location of trade effect.


2019 ◽  
Vol 24 (2) ◽  
pp. 199-217 ◽  
Author(s):  
Boy Lüthje

The article examines the development of advanced digital manufacturing (as outlined in the ‘Made-in-China 2025’ government plan) from the perspective of the changing socio-technical paradigms of production. The analysis focuses on the transformations of value chains and work, based on theories of social shaping of technology, regulation theory and regimes of production. Analytically, the author proposes to distinguish between ‘production-driven’ and ‘distribution-driven’ pathways of manufacturing digitalisation. The transformation of semi-rural industrial areas (‘Taobao villages’, named after China’s largest e-commerce platform Taobao) into mass production clusters for e-commerce is depicted as a paradigmatic model of distribution-driven transformation and as a characteristic Chinese strategy in this field. The article examines the impact on industry supply chains and work, leading to ever-more precarious conditions of employment. Policy recommendations focus on local strategies to stabilise supply chain structures and working conditions, as an alternative to the present top-down approaches to manufacturing modernisation in China.


2014 ◽  
Vol 915-916 ◽  
pp. 459-463
Author(s):  
He Quan Zhang

In order to deal with the impact on traffic flow of the rule, we compare the influence factors of traffic flow (passing, etc.) into viscous resistance of fluid mechanics, and establish a traffic model based on fluid mechanics. First, in heavy and light traffic, we respectively use this model to simulate the actual segment of the road and find that when the traffic is heavy, the rule hinder the further increase in traffic. For this reason, we make further improvements to the model to obtain a fluid traffic model based on no passing and find that the improved model makes traffic flow increase significantly. Then, the improved model is applied to the light traffic, we find there are no significant changes in traffic flow .In this regard we propose a new rule: when the traffic is light, passing is allowed, but when the traffic is heavy, passing is not allowed.


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