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The goal of this paper is to investigate theoretically the possible directions of some specified methods for the alternative roundabouts effectiveness modeling and optimization. The out-coming criteria have an economical interpretation. Those are the objective functionals of the alternative roundabouts effectiveness as the profit gained in the course of the traffic flow changes in the view of the integral form. This is modeled taking into consideration the transport infrastructure functioning elements such as the traffic flow of a capacity model. It takes into account two major components of the transportation services which are the alternative roundabouts business' incomes and expenses relating to the roundabouts transportation worthiness support. The prototypic approach is that one from the aircraft airworthiness support measures models. Corresponding managerial influences with respect to environmental, safety, utility, and other issues, as well as probable impacts, are modeled with the construction of the relevant under-integral expressions, equations, and appropriate coefficients and parameters of the mathematical mo dels. The achieved theoretical results, on the basis of the Euler-Lagrange equation and accepted assumptions, have been checked for the sufficiency of the objective functional maximum presence at the 'point' with the use of the conducted computer simulation. The necessary diagrams are plotted in order to illustrate the theoretical contemplations and speculations, as well as to check the correctness of the applied mathematical derivations and visualize the models' preciseness and abilities. The theoretically constructed mathematical models have a significance of the prognostic values applicability required at the alternative roundabouts effectiveness modeling and optimization ensuring their design progress and evolutions., 1. Introduction The complexity of the modern roundabouts design, their diversities in designations, and functional, economic, and environmental criteria structures elaboration [1] are predetermining the multialternativeness of the new types [...]

We consider continuous-time random walks on multidimensional symplectic lattices. It is shown that the generating functions of random walks and the transition amplitudes of continuous-time quantum walks can be expressed through dynamical correlation functions of an exactly solvable model describing strongly correlated bosons on a chain, the so-called phase model. The number of random lattice paths with a fixed number of steps connecting the starting and ending points on the multidimensionasl lattice is expressed through solutions of the Bethe equations of the phase model. Its asymptotics is obtained in the limit of a large number of steps. Bibliography: 31 titles., UDC 517.9 1. Introduction Classical random walks on a one-dimensional lattice have been intensively investigated for many years in mathematics and physics [1-6]. Quantum walks are unitary processes that describe [...]

Background: The Cameroon government has set a target that, by 2030, 58% of the population will be using Liquefied Petroleum Gas (LPG) as a cooking fuel, in comparison with less than 20% in 2014. The National LPG Master Plan (Master Plan) was developed for scaling up the LPG sector to achieve this target. Objectives: This study aimed to estimate the potential impacts of this planned LPG expansion (the Master Plan) on population health and climate change mitigation, assuming primary, sustained use of LPG for daily cooking. Methods: We applied existing and developed new mathematical models to calculate the health and climate impacts of expanding LPG primary adoption for household cooking in Cameroon over two periods: a) short-term (2017-2030): Comparing the Master Plan 58% target with a counterfactual LPG adoption of 32% in 2030, in line with current trends; and b) long-term (2031-2100, climate modeling only), assuming Cameroon will become a mature and saturated LPG market by 2100 (73% adoption, based on Latin American countries). We compared this with a counterfactual adoption of 41% by 2100, in line with current trends. Results: By 2030, successful implementation of the Master Plan was estimated to avert about 28,000 (minimum = 22,000, maximum = 35,000) deaths and 770,000 (minimum = 580,000 maximum = 1 million) disability-adjusted life years. For the same period, we estimated reductions in pollutant emissions of more than a third in comparison with the counterfactual, leading to a global cooling of -0.1 milli [degrees]C in 2030. For 2100, a cooling impact from the Master Plan leading to market saturation (73%) was estimated to be -0.70milli [degrees]C in comparison with to the counterfactual, with a range of -0.64 to -0.93 milli [degrees]C based on different fractions of nonrenewable biomass. Discussion: Successful implementation of the Master Plan could have significant positive impacts on population health in Cameroon with no adverse impacts on climate. https://doi.org/10.1289/EHP4899, Introduction Household air pollution (HAP) is a major risk factor for disease and disability in low- and middle-income countries (LMICs) (Gakidou et al. 2017). HAP is caused by incomplete combustion [...]

A model of three bidirectionally coupled phase oscillators in a ring is studied at the transition to a complete frequency synchronization. Analytic expressions for the critical coupling strengths, at which oscillators synchronize to a common frequency, are obtained. These expressions are determined for cases when the initial oscillators' frequencies are arranged arbitrarily or they are assigned according to fixed separations. Three unidirectionally coupled phase oscillators are synchronized in an analogous manner to the bidirectional system. This finding allows us to find an analytic equation for the critical coupling strength in the case of the model of the unidirectionally coupled phase oscillators. The bifurcation diagrams show excellent agreement between the analytic formulas and the numerical solutions of the differential equations that describe the models. Key words: frequency synchronization, Kuramoto model, coupled phase oscillators. Nous etudions un modele de trois oscillateurs bidirectionnels couples en phase dans un anneau a la transition vers une complete synchronisation en frequence. Il nous permet d'obtenir des expressions analytiques pour les forces de couplage critiques, auxquelles les oscillateurs se synchronisent a la meme frequence. Ces expressions sont determinees pour les cas ou les frequences initiales sont arbitraires ou avec des separations fixes. De la meme facon, trois oscillateurs unidirectionnels couples en phase sont egalement synchronises. Ce resultat permet de trouver une equation analytique pour les forces de couplage critiques dans le cas du modele des oscillateurs unidirectionnels couples en phase. Les diagrammes de bifurcation montrent un excellent accord entre les formules analytiques et les solutions numeriques des equations differentielles qui decrivent les modeles. [Traduit par la Redaction] Mots-cles: synchronisation en frequence, modele de Kuramoto, oscillateurs couples, dynamique non lineaire, methodes mathematiques en physique., 1. Introduction Coupled oscillators are used to understand the behavior of systems of interacting elements in physics, chemistry, biology, social relations, engineering, and technology [1-5]. Although all these systems have [...]

Anadolujet, a leading Turkish domestic airline carrier provides high-service, low-price flights to 28 locations within Turkey. Each winter and summer, Anadolujet typically generates a new flight schedule. The company's primary [...]

Rothermel's wildland surface fire spread model is widely used in North America. The model outputs depend on a number of input parameters, which can be broadly categorized as fuel model, fuel moisture, terrain, and wind parameters. Due to the inevitable presence of uncertainty in the input parameters, knowing the sensitivity of the model output to a given input parameter can be very useful for understanding and controlling the sources of parametric uncertainty. Instead of obtaining the local sensitivity indices, we perform a global sensitivity analysis that considers the synchronous changes of parameters in their respective ranges. The global sensitivity indices corresponding to different parameter groups are computed by constructing the truncated ANOVA--high dimensional model representation for the model outputs with a polynomial expansion approach. We apply global sensitivity analysis to six standard fuel models, namely short grass, tall grass, chaparral, hardwood litter, timber, and light logging slash. Our sensitivity results show similarities, as well as differences, between fuel models. For example, the sensitivities of the input parameters, i.e., fuel depth, low heat content, and wind, are large in all fuel models and as high as 85% of the total model variance in the fuel model light logging slash. On the other hand, the fuel depth explains around 40% of the total variance in the fuel model light logging slash but only 12% of the total variance in the fuel model short grass. The quantification of the importance of parameters across fuel models helps identify the parameters for which additional resources should be used to lower their uncertainty, leading to effective fire management. Key words: Rothermel fire spread model, global sensitivity analysis, high-dimensional model representation, Monte Carlo methods, ANOVA. Le modele de propagation des feux de foret de surface de Rothermel est largement utilise en Amerique du Nord. Les resultats du modele dependent de plusieurs parametres d'entree qui de facon generale peuvent etre assimiles au type de combustible, a l'humidite des combustibles ainsi qu'a des parametres associes au terrain et au vent. A cause de la presence inevitable d'incertitude dans les parametres d'entree, la sensibilite des resultats du modele a un parametre d'entree donne peut etre tres utile pour comprendre et controler les sources d'incertitude parametrique. Au lieu d'obtenir des indices locaux de sensibilite, nous avons effectue une analyse de sensibilite globale qui tient compte des changements synchrones des parametres dans les limites de leur amplitude respective. Les indices de sensibilite globale correspondants a differents groupes de parametres sont calcules en construisant une representation dimensionnelle au moyen d'une ANOVA tronquee pour les resultats du modele avec une approche d'expansion polynomiale. Nous avons applique l'analyse de sensibilite globale a six types standards de combustibles, soit les types herbes basses, herbes hautes, chaparral, litiere de feuillu, bois et residus de coupe fins. Nos resultats de sensibilite montrent qu'il y a des similitudes aussi bien que des differences entre les types de combustibles. A titre d'exemple, la sensibilite des parametres d'entree qui portent sur l'epaisseur des combustibles, le faible contenu calorifique et le vent est elevee pour tous les types de combustibles et aussi elevee que 85 % de la variance totale dans le cas des residus de coupe fins. D'autre part, l'epaisseur des combustibles explique environ 40 % de la variance totale dans le cas des residus de coupe fins, mais seulement 12 % dans le cas des herbes basses. La quantification de l'importance des parametres parmi les types de combustibles aide a identifier les parametres auxquels on devrait consacrer des ressources additionnelles pour reduire leur incertitude contribuant ainsi a une gestion efficace des feux. [Traduit par la Redaction] Mots-cles: modele de propagation du feu de Rothermel, analyse de sensibilite globale, representation dimensionnelle du modele, methodes de Monte Carlo, ANOVA., Introduction Wildland fire management requires an understanding of fire behaviors. Predicting fire behavior can be based solely on experience, which requires the predictor to have a profound comprehension of the [...]

Background Men who have sex with men (MSM) are at high risk for anal cancer, primarily related to human papillomavirus genotype 16 (HPV16) infections. At 8.5 per 100,000 per year, the incidence rate of anal cancer among MSM is similar to that of cervical cancer among adult women in the Netherlands. However, MSM are not included in most HPV vaccination programs. We explored the potential effectiveness of prophylactic immunization in reducing anogenital HPV16 transmission among MSM in the Netherlands. Methods and findings We developed a range of mathematical models for penile-anal HPV16 transmission, varying in sexual contact structure and natural history of infection, to provide robust and plausible predictions about the effectiveness of targeted vaccination. Models were informed by an observational cohort study among MSM in Amsterdam, 2010-2013. Parameters on sexual behavior and HPV16 infections were obtained by fitting the models to data from 461 HIV-negative study participants, considered representative of the local MSM population. We assumed 85% efficacy of vaccination against future HPV16 infections as reported for HIV-negative MSM, and age-specific uptake rates similar to those for hepatitis B vaccination among MSM in the Netherlands. Targeted vaccination was contrasted with vaccination of 12-year-old boys at 40% uptake in base-case scenarios, and we also considered the effectiveness of a combined strategy. Offering vaccine to MSM without age restrictions resulted in a model-averaged 27.3% reduction (90% prediction interval [PI] 11.9%-37.5%) in prevalence of anal HPV16 infections, assuming similar uptake among MSM as achieved for hepatitis B vaccination. The predicted reduction improved to 46.1% (90% PI 21.8%-62.4%) if uptake rates among MSM were doubled. The reductions in HPV16 infection prevalence were mostly achieved within 30 years of a targeted immunization campaign, during which they exceeded those induced by vaccinating 40% of preadolescent boys, if started simultaneously. The reduction in anal HPV16 prevalence amounted to 74.8% (90% PI 59.8%-93.0%) under a combined vaccination strategy. HPV16 prevalence reductions mostly exceeded vaccine coverage projections among MSM, illustrating the efficiency of prophylactic immunization even when the HPV vaccine is given after sexual debut. Mode of protection was identified as the key limitation to potential effectiveness of targeted vaccination, as the projected reductions were strongly reduced if we assumed no protection against future infections in recipients with prevalent infection or infection-derived immunity at the time of immunization. Unverified limitations of our study include the sparsity of data to inform the models, the omission of oral sex in transmission to the penile or anal site, and the restriction that our modeling results apply primarily to HIV-negative MSM. Conclusions Our findings suggest that targeted vaccination may generate considerable reductions in anogenital HPV16 infections among MSM, and has the potential to accelerate anal cancer prevention, especially when combined with sex-neutral vaccination in preadolescence., Author(s): Johannes A. Bogaards 1,2,*, Sofie H. Mooij 1,3, Maria Xiridou 1, Maarten F. Schim van der Loeff 3,4 Introduction Sexually transmitted oncogenic types of human papillomavirus (HPV) are known [...]

Traffic and transportation science consists of a broad range of topics. Traditional mathematical models and analysis techniques are not capable of translating many real-life problems in traffic and transportation engineering. [...]