Potential methods to forecast the actual highway capacity

Through movement capacity is an essential factor used to reflect intersection performance, especially for signalized intersections, where a large proportion of vehicle demand is making through movements. Generally, left-turn spillback is considered a key contributor to affect through movement capacity, and blockage to the left-turn bay is known to decrease left-turn capacity. Previous studies have focused primarily on estimating the through movement capacity under a lagging protected only left-turn (lagging POLT) signal setting, as a left-turn spillback is more likely to happen under such a condition. However, previous studies contained assumptions (e.g., omit spillback), or were dedicated to one specific signal setting. Therefore, in this study, through movement capacity models based on probabilistic modeling of spillback and blockage scenarios are established under four different signal settings (i.e., leading protected only left-turn [leading POLT], lagging left-turn, protected plus permitted left-turn, and permitted plus protected left-turn). Through microscopic simulations, the proposed models are validated, and compared with existing capacity models and the one in the Highway Capacity Manual (HCM). The results of the comparisons demonstrate that the proposed models achieved significant advantages over all the other models and obtained high accuracies in all signal settings. Each proposed model for a given signal setting maintains consistent accuracy across various left-turn bay lengths. The proposed models of this study have the potential to serve as useful tools, for practicing transportation engineers, when determining the appropriate length of a left-turn bay with the consideration of spillback and blockage, and the adequate cycle length with a given bay length.

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Assessment of Arterial Signal Timings Based on Various Operational Policies and Optimization Tools

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/03611981211011165 ◽

2021 ◽

pp. 036119812110111

Author(s):

Suhaib Al Shayeb ◽

Nemanja Dobrota ◽

Aleksandar Stevanovic ◽

Nikola Mitrovic

Keyword(s):

Travel Time ◽

Heavy Traffic ◽

Future Research ◽

Signal Timing ◽

Highway Capacity ◽

Average Delay ◽

Highway Capacity Manual ◽

Simulation And Optimization ◽

Fort Lauderdale ◽

Design Engineers

Traffic simulation and optimization tools are classified, according to their practical applicability, into two main categories: theoretical and practical. The performance of the optimized signal timing derived by any tool is influenced by how calculations are executed in the particular tool. Highway Capacity Software (HCS) and Vistro implement the procedures defined in the Highway Capacity Manual, thus they are essentially utilized by traffic operations and design engineers. Considering its capability of timing diagram drafting and travel time collection studies, Tru-Traffic is more commonly used by practitioners. All these programs have different built-in objective function(s) to develop optimized signal plans for intersections. In this study, the performance of the optimal signal timing plans developed by HCS, Tru-Traffic, and Vistro are evaluated and compared by using the microsimulation software Vissim. A real-world urban arterial with 20 intersections and heavy traffic in Fort Lauderdale, Florida served as the testbed. To eliminate any bias in the comparisons, all experiments were performed under identical geometric and traffic conditions, coded in each tool. The evaluation of the optimized plans was conducted based on average delay, number of stops, performance index, travel time, and percentage of arrivals on green. Results indicated that although timings developed in HCS reduced delay, they drastically increased number of stops. Tru-Traffic signal timings, when only offsets are optimized, performed better than timings developed by all of the other tools. Finally, Vistro increased arrivals on green, but it also increased delay. Optimized signal plans were transferred manually from optimization tools to Vissim. Therefore, future research should find methods for automatically transferring optimized plans to Vissim.

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Designing of Green Plasticizers and Assessment of the Effectiveness of Their Use

Polymers ◽

10.3390/polym13111761 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1761

Author(s):

Aliya K. Mazitova ◽

Guliya K. Aminova ◽

Irina N. Vikhareva

Keyword(s):

Adipic Acid ◽

Polymer Materials ◽

Operational Parameters ◽

Solid Domestic Waste ◽

Polymer Waste ◽

Synthetic Materials ◽

Environmental Requirements ◽

Potential Methods ◽

High Set ◽

Acid Esters

The growing anthropogenic load on the lithosphere is currently characterized by the alienation of huge areas for solid domestic waste. One of the most common pollutants is traditional plastics with a degradation period of over 100 years. In connection with the increasing environmental requirements, polymer materials, along with a high set of technological and operational parameters, must be environmentally friendly and biodegradable. The development of polymer composite materials that undergo accelerated physicochemical and biological changes in the natural environment due to the introduction of biodegradable additives is one of the potential methods for processing synthetic materials and ensures the release of significant areas of fertile soils and lands from the steadily increasing amount of polymer waste. The use of adipic acid esters as PVC plasticizers contributes to the production of biodegradable composites. The article describes a method for obtaining new esters of adipic acid, presents the results of studying their properties for practical use in PVC composites, and assesses the economic efficiency of preventing damage to the environment when using them.

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Examining sharp restart in a Monte Carlo method for the linearized Poisson–Boltzmann equation

Monte Carlo Methods and Applications ◽

10.1515/mcma-2020-2069 ◽

2020 ◽

Vol 26 (3) ◽

pp. 223-244

Author(s):

W. John Thrasher ◽

Michael Mascagni

Keyword(s):

Monte Carlo ◽

Free Energy ◽

Monte Carlo Algorithm ◽

Significant Bias ◽

Poisson Boltzmann ◽

Electrostatic Free Energy ◽

Poisson Boltzmann Equation ◽

The Stability ◽

Potential Methods ◽

The Individual

AbstractIt has been shown that when using a Monte Carlo algorithm to estimate the electrostatic free energy of a biomolecule in a solution, individual random walks can become entrapped in the geometry. We examine a proposed solution, using a sharp restart during the Walk-on-Subdomains step, in more detail. We show that the point at which this solution introduces significant bias is related to properties intrinsic to the molecule being examined. We also examine two potential methods of generating a sharp restart point and show that they both cause no significant bias in the examined molecules and increase the stability of the run times of the individual walks.

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Concentration-Dependent Feeding Deterrence to 20-Hydroxyecdysone for Three Subterranean Termite Species (Blattodea: Rhinotermitidae)

Insects ◽

10.3390/insects12030218 ◽

2021 ◽

Vol 12 (3) ◽

pp. 218

Author(s):

Lucas Carnohan ◽

Sang-Bin Lee ◽

Nan-Yao Su

Keyword(s):

Reticulitermes Flavipes ◽

Coptotermes Formosanus ◽

Subterranean Termite ◽

Choice Test ◽

Molting Hormone ◽

Feeding Deterrence ◽

Insect Feeding ◽

Substrate Consumption ◽

Termite Species ◽

Potential Methods

Effective active ingredients in toxicant bait formulations must be non-deterrent to insect feeding behavior at lethal concentrations. This study evaluated feeding deterrence for Coptotermes formosanus Shiraki, C. gestroi (Wasmann), and Reticulitermes flavipes (Kollar) when provided access to cellulose impregnated with various concentrations of the insect molting hormone, 20-hydroxyecdysone (20E). Termites were exposed to 20E concentrations of 200, 500, 1000 and 2000 ppm and to noviflumuron at 5000 ppm in a 24 h choice-test, and the mass of substrate consumption from treated and untreated media pads was compared for each treatment. 20E feeding deterrence was detected at 500, 1000 and 2000 ppm for C. gestroi, and at 2000 ppm for C. formosanus. No significant differences in consumption of treated and untreated substrate was detected at any concentration for R. flavipes. Potential methods for reducing deterrence are discussed.

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Uncertainty analysis of hydroelastic responses and wave loads for different structural modeling and potential methods

Ocean Engineering ◽

10.1016/j.oceaneng.2020.108529 ◽

2021 ◽

Vol 222 ◽

pp. 108529

Author(s):

Peng Yang ◽

Wei Zhang ◽

Xueliang Wang ◽

Juan Jiang ◽

Jiajun Hu ◽

...

Keyword(s):

Uncertainty Analysis ◽

Structural Modeling ◽

Wave Loads ◽

Potential Methods

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Comprehensive Plasma Metabolomic Profile of Patients with Advanced Neuroendocrine Tumors (NETs). Diagnostic and Biological Relevance

Cancers ◽

10.3390/cancers13112634 ◽

2021 ◽

Vol 13 (11) ◽

pp. 2634

Author(s):

Beatriz Soldevilla ◽

Angeles López-López ◽

Alberto Lens-Pardo ◽

Carlos Carretero-Puche ◽

Angeles Lopez-Gonzalvez ◽

...

Keyword(s):

Metabolic Pathways ◽

Metabolic Networks ◽

Tca Cycle ◽

Metabolomic Profile ◽

Diagnostic Potential ◽

The Tca Cycle ◽

Novel Biomarkers ◽

Potential Methods ◽

Clinical Potential ◽

First Time

Purpose: High-throughput “-omic” technologies have enabled the detailed analysis of metabolic networks in several cancers, but NETs have not been explored to date. We aim to assess the metabolomic profile of NET patients to understand metabolic deregulation in these tumors and identify novel biomarkers with clinical potential. Methods: Plasma samples from 77 NETs and 68 controls were profiled by GC−MS, CE−MS and LC−MS untargeted metabolomics. OPLS-DA was performed to evaluate metabolomic differences. Related pathways were explored using Metaboanalyst 4.0. Finally, ROC and OPLS-DA analyses were performed to select metabolites with biomarker potential. Results: We identified 155 differential compounds between NETs and controls. We have detected an increase of bile acids, sugars, oxidized lipids and oxidized products from arachidonic acid and a decrease of carnitine levels in NETs. MPA/MSEA identified 32 enriched metabolic pathways in NETs related with the TCA cycle and amino acid metabolism. Finally, OPLS-DA and ROC analysis revealed 48 metabolites with diagnostic potential. Conclusions: This study provides, for the first time, a comprehensive metabolic profile of NET patients and identifies a distinctive metabolic signature in plasma of potential clinical use. A reduced set of metabolites of high diagnostic accuracy has been identified. Additionally, new enriched metabolic pathways annotated may open innovative avenues of clinical research.

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A quantum chemical study of the dimerization of indanedionyl radicals by the indo and molecular electrostatic potential methods

Bulletin of the Academy of Sciences of the USSR Division of Chemical Science ◽

10.1007/bf00947725 ◽

1985 ◽

Vol 34 (3) ◽

pp. 571-575

Author(s):

V. B. Luzhkov ◽

V. I. Nikulin ◽

L. M. Pisarenko ◽

G. N. Bogdanov

Keyword(s):

Electrostatic Potential ◽

Quantum Chemical ◽

Molecular Electrostatic Potential ◽

Quantum Chemical Study ◽

Chemical Study ◽

Potential Methods

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Estimating the Effects of Urban Street Incidents on Capacity

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/2615-07 ◽

2017 ◽

Vol 2615 (1) ◽

pp. 55-61 ◽

Cited By ~ 2

Author(s):

Aidin Massahi ◽

Mohammed Hadi ◽

Maria Adriana Cutillo ◽

Yan Xiao

Keyword(s):

Network Performance ◽

Field Measurements ◽

Signalized Intersection ◽

Limited Information ◽

Microscopic Simulation ◽

Highway Capacity ◽

Highway Capacity Manual ◽

Urban Streets ◽

Urban Street ◽

Incident Duration

The effect of incidents on capacity is the most critical parameter in estimating the influence of incidents on network performance. The Highway Capacity Manual 2010 (HCM 2010) provides estimates of the drop in capacity resulting from incidents as a function of the number of blocked lanes and the total number of lanes in the freeway section. However, there is limited information on the effects of incidents on the capacity of urban streets. This study investigated the effects on capacity of the interaction between the drop in capacity below demand at a midblock urban street segment location and upstream and downstream of signalized intersection operations. A model was developed to estimate the drop in capacity at the incident location as a function of the number of blocked lanes, the distance from the downstream intersection, and the green time–to–cycle length (g:C) ratio of the downstream signal. A second model was developed to estimate the reduction in the upstream intersection capacity resulting from the drop in capacity at the midblock incident location as estimated by the first model. The second model estimated the drop in capacity of the upstream links feeding the incident locations as a function of incident duration time, the volume-to-capacity (V/C) ratio at the incident location, and distance from an upstream signalized intersection. The models were developed on the basis of data generated with the use of a microscopic simulation model calibrated by comparison with parameters suggested in HCM 2010 for incident and no-incident conditions and by comparison with field measurements.

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