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This study focuses on characterizing the fatigue damage accumulated in nonlinear aeroelastic systems subjected to stochastic inflows through both numerical simulations and wind tunnel experiments. In the mathematical model, nonlinearities are assumed to exist either in the structure (via a cubic hardening nonlinearity in the pitch stiffness), or in the flow (via dynamic stall condition), or simultaneously in both the structural and aerodynamic counterparts. The aerodynamic loads in the attached flow and dynamic stall conditions are estimated using Wagner's formulation and semi-empirical Leishman–Beddoes model, respectively. To augment the findings to in-field flow conditions, the oncoming wind flow is considered to be randomly time-varying in nature. The stochastic input flow fluctuations are modeled using a Karhunen–Loeve Expansion formulation. The response dynamics and the associated fatigue damage of the aeroelastic system, possessing different sources of nonlinearities, are systematically investigated under isolated cases of deterministic and stochastic input flows. Specifically, the pertinent role of stochasticity in the input flow is brought out by presenting the response dynamics and the associated fatigue damage accumulation for different values of noise intensity and time scale of the input flow fluctuation. It is demonstrated that under fluctuating flow conditions, the dynamics intermittently switch between attached flow and the dynamic stall regimes even at low mean flow speeds. The intermittent nature of the response varies as the time scale and intensity of the oncoming flow are varied. The role of torsional stresses as the predominant component dictating the fatigue damage accumulation irrespective of the source of nonlinearity is illustrated. Using the rainflow counting method and Miner's linear damage accumulation theory, it is shown that the accumulated fatigue damage is substantially higher under stochastic flow conditions as compared to deterministic input flows. Importantly, it is observed that different time scales and intensities of the oncoming flow fluctuation play a pivotal role in dictating the fatigue damage in aeroelastic systems. Finally, fatigue damage is observed to be significantly higher for torsionally dominant oscillations in the dynamical stall regime compared to the oscillations at the attached flow regime. The numerical findings are strengthened by drawing comparisons with the preliminary results obtained from wind tunnel experiments performed on a NACA 0012 airfoil undergoing dynamic stall. To the best of our knowledge, this is the first study that systematically bridges the dichotomy between the stall-induced dynamical signatures in stochastic aeroelastic systems and maps the same to the corresponding structural damage.

Many real-world networks such as freight, power and long distance transportation networks are represented as multi-source multi-sink stochastic flow network. The objective is to transmit flow successfully between the source and the sink nodes. The reliability of the capacity vector of the assigned components is used an indicator to find the best flow strategy on the network. The Components Assignment Problem (CAP) deals with searching the optimal components to a given network subject to one or more constraints. The CAP in multi-source multi-sink stochastic flow networks with multiple commodities has not yet been discussed, so our paper investigates this scenario to maximize the reliability of the capacity vector subject to an assignment budget. The mathematical formulation of the problem is defined, and a proposed solution based on genetic algorithms is developed consisting of two steps. The first searches the set of components with the minimum cost and the second searches the flow vector of this set of components with maximum reliability. We apply the solution approach to three commonly used examples from the literature with two sets of available components to demonstrate its strong performance.

Network reliability evaluation for a stochastic flow network (SFN) can be computed in terms of all lower boundary points (LBPs). Although several algorithms have been presented in the literature as solutions for the LBP problem, the efficiency is always occurring at the present for the large SFN. In this paper, a binding technique generating binding-flow vectors is therefore developed to narrow down the searching range of flows for demand. This technique is able to reduce the loading of the candidate comparison procedure greatly. An algorithm based on this binding technique is proposed to solve the LBP problem. We compare the performance of the proposed algorithm to well-known algorithms in terms of CPU time, through three benchmark networks and a practical case. The experimental results show the functional efficiency of our proposed binding LBP algorithm.

In the tourism sector, travel agent’s managers often set meeting customers’ demand as a top priority and often get discounts from airlines and the discounted fare on each flight depends on their booking, whereas, customers have their request in terms of travel time and cost. This study addresses the network reliability, the probability that the given demand can travel from an origin to a destination within the time threshold and the travel cost after discount does not exceed the budget, to indicate travel agents’ ability on satisfying customers’ demand under specific constraints. To calculate the network reliability, this work develops an algorithm, which determines all lower boundary points via the minimal concept. An air transportation system of the travel agent is constructed as a flow-network consisting of sets of nodes (airports) and arcs (flights). On each flight, there exists a contracted airline providing the service with stochastic capacity and corresponding probability. The flow-network in this study is typical stochastic, called a stochastic-flow air transportation network. A real case for the proposed algorithm demonstration and some management suggestions of the network reliability are provided.

Introduction. The article considers the problem of distribution of available and leased vehicles for servicing the stochastic flow of long-distance freight orders. The content of the problem is that the total amount of jobs should be divided between the available vehicles and those that can be rented from partners, so that the overall efficiency of transport processes and the total profit of the enterprise are maximum. The problem is relevant today because the requirements for carriers are growing, their operational management tasks are becoming more complicated, and effective methods that provide guaranteed accurate optimal solutions are unknown. The purpose of research is to determine the signs of organizational and technological compatibility of transport process tasks, the implementation of which in united flow is effective. The use of such features should lead to a guaranteed accurate solution of the problem of distribution of vehicles with a random nature of input flows. Results. The vehicles ordering that arise stochastically is NP-difficult task of strong sense. Additional classification features of orders are offered, which allow us to find a guaranteed stable solution. This solution is possible due to the fact that compatible or partially compatible orders are pre-combined into sets that are intended to be executed in a single flow, and single vehicle. The model of nonlinear programming is applied. To distribute the dynamic input flow of orders the distribution problem was solved with a stable result. The solution criterion is the total profit that the road carrier can receive with the proposed sequence of orders. Optimization at linear approximation of total profit on signs of compatibility of orders is executed. Conclusions. Structural modeling of the integrated transport process should be carried out for specific signs of compatibility of the incoming flow of orders. A sign of compatibility of orders is the coefficient of time unevenness, has a positive effect on the ability to obtain a higher maximum total profit. Linear approximation of the model gives more than 100% error of results.

Orientadores: Paulo Regis Caron Ruffino, Xue-Mei Hairer Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Matemática, Estatística e Computação Científica Resumo: Seja $M$ uma variedade compacta munida de um par de folheações complementares (vertical e horizontal). O objetivo desta tese é estudar decomposições de fluxos de difeomorfismos em um contexto de baixa regularidade. Provamos que dado um semimartingale $Z_t$ (o qual pode ter infinitos saltos em intervalos compactos), então, até um tempo de parada $\tau$, um fluxo de difeomorfismo em $M$ dirigido por $Z_t$ pode ser decomposto em um processo no grupo de Lie de difeomorfismos cujas trajetórias caminham ao longo das folhas horizontais composto com um processo no grupo de difeomorfismos cujas trajetórias caminham ao longo das folhas verticais. Equações para estes processos são determinadas. Os processos estocásticos com componentes de saltos são gerados por equações de Marcus (como em Kurtz, Pardoux and Protter, Annal. I.H.P., section B, 31 (1995)). Generalizamos ainda mais este contexto geométrico para quaisquer tipo de semimartingales. Mostramos também que esta decomposição também funciona para soluções de equações diferenciais de Young e exploramos alguns aspectos geométricos da integral de Young. No contexto de saltos, nossa técnica é baseada em uma extensão da fórmula de Itô-Ventzel-Kunita para processos com saltos. No contexto de integrais de Young, fazemos uma aplicação de uma fórmula de Itô-Ventzel-Kunita para caminhos $\alpha$-H{\"o}lder Contínuos proposta por Castrequini e Catuogno (Chaos Solitons Fractals, 2022). Algumas obstruções geométricas e topológicas para decomposições também são consideradas Abstract: Let $M$ be a compact manifold equipped with a pair of complementary foliations, say horizontal and vertical. This thesis aims to study a decomposition of flows of diffeomorphisms in the low regularity context. Namely, we prove that given a general semimartingale $Z_t$ (which can have an infinity number of jumps in compact intervals) up to a stopping time $\tau$, a stochastic flow of local diffeomorphisms in $M$ driven by $Z_t$ can be decomposed into a process in the Lie group of diffeomorphisms which trajectories remain along the horizontal leaves composed with a process in the Lie group of diffeomorphisms which trajectories remain along the vertical leaves. SDEs of these processes are shown. The stochastic flows with jumps are generated by the classical Marcus equation (as in Kurtz, Pardoux and Protter, Annal. I.H.P., section B, 31 (1995)). We enlarge the scope of this geometric decomposition and consider flows driven by arbitrary semimartingales with jumps. We show that this decomposition also holds for solutions of Young differential equations exploring the geometry of Young integrals. In the jump context, our technique is based on our extension of the Itô-Ventzel-Kunita formula for stochastic flows, which may jump infinitely many times. In the Young integral context, we apply a Young Itô-Kunita formula for $\alpha$-H{\"o}lder paths proved by Castrequini and Catuogno (Chaos Solitons Fractals, 2022). Geometrical and other topological obstructions for the decomposition are also considered, e.g., sufficient conditions for the existence of global decomposition for all $t\geq 0$ Doutorado Matemática Doutor em Matemática CAPES 001

Orientador: Paulo Regis Caron Ruffino Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Matemática Estatística e Computação Científica Resumo: Neste trabalho tratamos de dois aspectos relativos à fluxos estocásticos em folheações. Na primeira parte tratamos da decomposição de um fluxo f(t,.)=h(t,v(t,.)) em uma variedade diferenciável com duas folheações transversais entre si (M,H, V) de modo que h(t,.) preserva as folhas de H e v(t,.) preserva as folhas de V. Nesta parte estudamos como certas propriedades topológicas das folheações, tais como interseções de folhas e atingibilidade, influenciam na decomposição. Por fim mostramos que quando H é transversalmente orientável, um fluxo é decomponível se e somente se preserva esta orientação. Como aplicação deste resultado obtemos uma condição suficiente para que o fluxo de uma e.d.e. de Stratonovich seja decomponível. Na segunda parte obtemos uma medida \nu definida em subvariedades de M transversais à H a qual é invariante pelo fluxo f(t,.) gerado por uma equação de Stratonovich. Posteriormente estudamos recorrência destes fluxos em relação à topologia gerada por abertos H-saturados Abstract: This work approaches two problems concerning flows in foliated manifolds. The first part deals with the decomposition of a flow f(t,.) =h(t,v(t,.)) in a bifoliated differentiable manifold (M, H, V), where h(t,.) preserves the leaves of H and v(t,.) preserves V. In this part we study the way topological features, such as attainability and intersection of leaves, influence the decomposition. Finally, we present a complete description of decomposability in terms of the topology of the foliations by proving that when H is transversaly orientable f(t,.) is decomposable if and only if it preserves the transversal orientation. Afterwards we give a sufficient condition for the flow of an Stratonovich s.d.e to be decomposable. In the second part we provide an invariant measure on submanifolds of M that are transversal to H, and we use it to study recurrence Doutorado Matemática Doutor em Matemática CNPQ 142084/2012-3 CAPES

We have studied the efficiency of organization of transfer trains at developed railroad junctions based on the criterion of total hours of railroad wagon downtime under accumulation. We have constructed discrete-event simulation models (Java SE, AnyLogic) of the organization of transfer trains in line with a "rigid schedule" and under accumulation to the standard for trains. The models take into consideration the stochastic nature of wagon arrivals to the accumulation points and meeting the established norm for the mass of trains. It is considered at modeling that track development of railroad stations and intranodal passages is rational and does not significantly affect delay in the motion of transfer trains. The transfer trains schedule is rational and rhythmic. The throughput capacity of open tracks at a node and the processing capability of subsystems at railroad stations are sufficient. We have experimentally compared the efficiency of four models of the organization of transfer trains, including a "flexible model", which combines dispatch upon accumulation to the standard of a train and a "rigid schedule" at the same time. It was established that the minimal hours of wagon accumulation are achieved when transfer trains are organized via a combined variant: a simultaneous dispatch in line with a "rigid schedule" and at accumulation to the standard. Organization of transfer trains in line with a "rigid schedule" requires the organization of additional trains, otherwise there is an increase in the queue of wagons at accumulation points. When increasing the number of daily trains by 10‒11 %, the process of forming and dispatching becomes sufficiently reliable and efficient. The specified recommendations would make it possible to improve the typical process of operation of railroad junctions in terms of dispatcher control over the formation, dispatch, and passing of transfer trains during intranodal traffic

Monocrystalline, cast aluminium microwires of diameter (D) below 25 mu m free of micromilling artefacts are annealed under protective atmosphere. Annealing increases the flow stress of all tested microwires, by an amount that is found, in a Haasen plot of measured activation area values, to be an athermal contribution to the flow stress that is attributed to surface oxide layer thickening. Microwires oriented for single slip with D similar to 14 mu m behave as do as-cast microwires with D similar to 7 mu m, showing a transition to higher and more stochastic flow stress values; this effect is attributed to a greater scarcity of dislocation sources after annealing. (C) 2018 Acta Materialia Inc. Published by Elsevier Ltd.

We consider the following stochastic partial differential equation, $$\begin{array}{@{}rcl@{}} &&dY_{t} = L^{\ast} Y_{t} dt + A^{\ast} Y_{t} \cdot dB_{t}\\ &&Y_{0} = \psi, \end{array} $$ associated with a stochastic flow {X(t,x)}, for t ≥ 0, $x \in \mathbb {R}^{d}$ , as in Rajeev and Thangavelu (Potential Anal. 28(2), 139–162, 2008). We show that the strong solutions constructed there are ‘locally of compact support’. Using this notion,we define the mild solutions of the above equation and show the equivalence between strong and mild solutions in the multi Hilbertian space $\mathscr{S}^{\prime }$ . We show uniqueness of solutions in the case when ψ is smooth via the ‘monotonicity inequality’ for (L∗,A∗), which is a known criterion for uniqueness.

The method of characteristics is a powerful tool to solve some nonlinear second order stochastic PDEs like those satisfied by a consistent dynamic utilities, see [EM13, MM20]. In this situation the solution V (t, z) is theoretically of the formX t V (0,ξ t (z)) whereX and Y are solutions of a system of two SDEs,ξ is the inverse flow ofȲ and V (0, .) is the initial condition. Unfortunately this representation is not explicit except in simple cases whereX andȲ are solutions of linear equations. The objective of this work is to take advantage of this representation to establish a numerical scheme approximating the solution V using Euler approximations X N and ξ N of X and ξ. This allows us to avoid a complicated discretizations in time and space of the SPDE for which it seems really difficult to obtain error estimates. We place ourselves in the framework of SDEs driven by Lévy noise and we establish at first a strong convergence result, in L p-norms, of the compound approximation X N t (Y N t (z)) to the compound variable X t (Y t (z)), in terms of the approximations of X and Y which are solutions of two SDEs with jumps. We then apply this result to Utility-SPDEs of HJB type after inverting monotonic stochastic flows.

Industry 4.0 is widely accepted in manufacturing industry since it guides a novel and promising production paradigm. A new characteristic in Industry 4.0-based manufacturing systems is that the applications of advanced intelligent machines which have communication, self-optimization and self-training behaviors. Based on this new change, this study investigates a flow-shop scheduling problem under the consideration of multiple objectives, time-dependent processing time and uncertainty. A mixed integer programming model is formulated for this problem, and a fireworks algorithm is developed where some special strategies are designed, e.g., explosion sparks procedure and selection solution procedure. Simulation experiments on a set of test problems are carried out, and the experimental results demonstrate that the model and proposed algorithm can achieve a satisfactory performance by comparing with three state-of-the-art multi-objective optimization algorithms.

In the case of an existing limited capacity of the system called required system capacity, in this study a new method is presented to determine the disjoint paths to send data from the source to the sink. System reliability is evaluated as the probability that a specified amount of data can be transmitted from a source to a sink through two disjoint paths, subject to a time threshold and a required capacity. In addition, we study the effect of using the proposed method on the reliability evaluation in comparison with other previous methods.

Formation of rational delivery routes is the main way to increase the effectiveness of client services for freight forwarding companies. The main part of the requests for transport services comes from occasional (non-constant) clients. The set of those requests forms a stochastic flow. For stochastic requests flow, the delivery routes are formed in the process of the requests receipt. Therefore, the standard approaches for merging of requests from multiple clients into routes, based on linear programming techniques, cannot be used in such conditions. An algorithm of formation under the stochastic demand conditions of such delivery routes, which allow servicing of two or more shippers, is proposed in the paper. The author has developed a specialized software to support decisions made by dispatchers of forwarding companies.

In this paper, we will try to study the same result proved in \cite{10}. So, on the same model and with some assumptions, we will study the property of homeomorphism of the stochastic flow generated by the natural model in a one-dimensional case and with some modifications, based on an important theory of Hiroshi Kunita. This is the main motivation of our research.

In this paper we investigate the regularity properties of strong solutions to SDEs driven by L\'evy processes with irregular drift coefficients. Under some mild conditions, we show that the singular SDE has a unique strong solution for each starting point and the family of all the solutions forms a stochastic flow. Moreover, the Malliavin differentiability of the strong solutions is also obtained. As an application, we also prove a path-by-path uniqueness result for some related random ODEs., Comment: 28 pages

This paper evaluates the standard empirical methods employed in the study of foreign aid, when the data generating process is a calibrated stochastic growth model in which aid recipients make optimal investment and consumption decisions. When recipients receive a stochastic flow of aid and wish to smooth consumption, standard methods fail to distinguish between the response to transient and permanent aid shocks, and hence yield misleading results concerning the object of interest to policy makers: the long-run impact of aid.

The new conception of seismic data analysis is proposed. It is based on preliminary studying of seismic background. Its characteristics are a base for using mathematical models of non realizable seismic signals. The specific mathematical model of the seismic signal is proposed as well. The peculiarity of the model is that it allows you to simulate the flow of seismic waves of different classes each of them appears in the stream with specific time delay. This process takes place against the micro-seismic background noise. It is natural to model the flow of signals by the physically realizable signal. It means those signals which do not have a trace in prehistory. But this representation of the signal is unacceptable for two reasons. The first one is related to the smoothness of the signal at the time of its appearance on the seismic record. The second one is related to the fact that the fade of the signal in the noise does not allow us to determine the time of its appearance on the record accurately. The latter circumstance does not leave us the possibility to simulate the time of the signal occurrence by using the determined value. Therefore, the time of occurrence of the signal is simulated by random variable with variance depending on the level of micro-seismic background. We introduce the notion of generalized seismic signal as a function of time and of the vector of parameters, which determine its shape, the energy, the place in flow of the other signals, spectral characteristics, and in general behavior in the entire history of its existence. Any widely spread seismic signal models used in practice are a particular case of this one. Or in a more rigorous approach to the definition the different particular cases of the signals classes are transformed into the different hyper-planes into space of parameters. Запропоновано нову концепцію аналізу сейсмічних даних. Вона базується на попередньому вивченні сейсмічного фону. Для його параметризації використовується математична модель з фізично нездійсненними сигналами. Також пропонується специфічна математична модель самого сейсмічного сигналу. Особливість моделі полягає в тому, що вона дозволяє симулювати сейсмічні хвилі різними класами сигналів, кожен з яких з’являється в потоці зі своєю тимчасовою затримкою. Цей процес розглядається на мікросейсмічному фоні. Природно моделювати потік фізично здійсненними сигналами. Мається на увазі, що сигнали не мають передісторії. Але таке уявлення сигналу неприйнятно з двох причин. Перша пов'язана з гладкістю сигналу в точці його появи на сейсмічному записі. Друга пов'язана з тим, що на фоні сейсмічного шуму не можливо чітко виділити час вступу сигналу. Остання обставина не дає можливості отримати точний детермінований час вступу сигналу. Тому час вступу сигналу представляється як випадкова величина з довірчим інтервалом, що залежить від рівня мікросейсмічних шуму. Поняття узагальненого сейсмічного сигналу представлено як функцію часу і вектора параметрів, які визначають його форму, енергію, місце в потоці інших сигналів, його спектральні характеристики і в цілому його поведінку в усій історії його існування. Будь-яка широко поширена модель сейсмічного сигналу є окремим випадком запропонованої моделі. Або, більш строго, будь-який інший клас широко відомих моделей сейсмічного сигналу є гіперплощиною в просторі параметрів запропонованої моделі.

For stochastic flow network (SFN), given all the lower (or upper) boundary points, the classic problem is to calculate the probability that the capacity vectors are greater than or equal to the lower boundary points (less than or equal to the upper boundary points). However, in some practical cases, SFN reliability would be evaluated between the lower and upper boundary points at the same time. The evaluation of SFN reliability with upper and lower boundary points at the same time is the focus of this paper. Because of intricate relationships among upper and lower boundary points, a decomposition approach is developed to obtain several simplified subsets. SFN reliability is calculated according to these subsets by means of the inclusion-exclusion principle. Two heuristic options are then established in order to calculate SFN reliability in an efficient direction based on the lower and upper boundary points.

Reflected diffusions in convex polyhedral domains arise in a variety of applications, including interacting particle systems, queueing networks, biochemical reaction networks and mathematical finance. Under suitable conditions on the data, we establish pathwise differentiability of such a reflected diffusion with respect to its defining parameters --- namely, its initial condition, drift and diffusion coefficients, and (oblique) directions of reflection along the boundary of the domain. We characterize the right-continuous regularization of a pathwise derivative of the reflected diffusion as the pathwise unique solution to a constrained linear stochastic differential equation with jumps whose drift and diffusion coefficients, domain and directions of reflection depend on the state of the reflected diffusion. The proof of this result relies on properties of directional derivatives of the associated (extended) Skorokhod reflection map and their characterization in terms of a so-called derivative problem, and also involves establishing certain path properties of the reflected diffusion at nonsmooth parts of the boundary of the polyhedral domain, which may be of independent interest. As a corollary, we obtain a probabilistic representation for derivatives of expectations of functionals of reflected diffusions, which is useful for sensitivity analysis of reflected diffusions., Comment: 37 pages

We consider a stochastic flow $\phi_t(x,\omega)$ in $\mathbb{R}^n$ with initial point $\phi_0(x,\omega)=x$, driven by a single $n$-dimensional Brownian motion, and with an outward radial drift of magnitude $\frac{ F(\|\phi_t(x)\|)}{\|\phi_t(x)\|}$, with $F$ nonnegative, bounded and Lipschitz. We consider initial points $x$ lying in a set of positive distance from the origin. We show that there exist constants $C^*,c^*>0$ not depending on $n$, such that if $F>C^*n$ then the image of the initial set under the flow has probability 0 of hitting the origin. If $0\leq F \leq c^*n^{3/4}$, and if the initial set has nonempty interior, then the image of the set has positive probability of hitting the origin., Comment: 34 pages, 3 figures

We have studied the efficiency of organization of transfer trains at developed railroad junctions based on the criterion of total hours of railroad wagon downtime under accumulation. We have constructed discrete-event simulation models (Java SE, AnyLogic) of the organization of transfer trains in line with a "rigid schedule" and under accumulation to the standard for trains. The models take into consideration the stochastic nature of wagon arrivals to the accumulation points and meeting the established norm for the mass of trains. It is considered at modeling that track development of railroad stations and intranodal passages is rational and does not significantly affect delay in the motion of transfer trains. The transfer trains schedule is rational and rhythmic. The throughput capacity of open tracks at a node and the processing capability of subsystems at railroad stations are sufficient.We have experimentally compared the efficiency of four models of the organization of transfer trains, including a "flexible model", which combines dispatch upon accumulation to the standard of a train and a "rigid schedule" at the same time. It was established that the minimal hours of wagon accumulation are achieved when transfer trains are organized via a combined variant: a simultaneous dispatch in line with a "rigid schedule" and at accumulation to the standard. Organization of transfer trains in line with a "rigid schedule" requires the organization of additional trains, otherwise there is an increase in the queue of wagons at accumulation points. When increasing the number of daily trains by 10‒11 %, the process of forming and dispatching becomes sufficiently reliable and efficient.The specified recommendations would make it possible to improve the typical process of operation of railroad junctions in terms of dispatcher control over the formation, dispatch, and passing of transfer trains during intranodal traffic, Проведено исследование эффективности организации передаточных поездов в развитых железнодорожных узлах по критерию совокупных вагоно-часов простоя под накоплением. Разработаны дискретно-событийные имитационные модели (Java SE, AnyLogic) организации передаточных поездов по «жесткому графику» и за накоплением до нормы составов. В моделях учтена стохастическая природа поступления вагонов в пункты накопления и выполнение установленной нормы массы составов. При моделировании считается, что путевое развитие железнодорожных станций и внутриузловых ходов является рациональным, и несущественно влияет на задержку движения передаточных поездов. График движения передаточных поездов рациональный и ритмичный. Пропускная способность перегонов узла и перерабатывающая способность подсистем железнодорожных станций являются достаточными.Экспериментально проведено сравнение эффективности четырех моделей организации передаточных поездов, в том числе «гибкой моделью», которая объединяет отправление по накоплению до нормы состава и «жесткому графику» одновременно. Установлено, что минимальные вагоно-часы накопления достигаются при организации передаточных поездов комбинированным вариантом: одновременное отправление и по «жесткому графику» и при накоплении до нормы. Организация передаточных поездов по «жесткому графику» требует организации дополнительных поездов, иначе существенно возрастает очередь из вагонов в пунктах накопления. При увеличении суточного количества поездов на 10–11 % процесс формирования и отправки становится достаточно надежным и эффективным.Обозначенные рекомендации позволят усовершенствовать типовой процесс работы железнодорожных узлов в части диспетчерского контроля за формированием, отправлением и пропуском передаточных поездов во внутриузловом сообщении, Проведено дослідження ефективності організації передавальних поїздів в розвинених залізничних вузлах за критерієм сукупних вагоно-годин простою під накопиченням. Розроблені дискретно-подієві імітаційні моделі (Java SE, AnyLogic) організації передавальних поїздів за «жорстким графіком» та за накопиченням до норми составів. В моделях враховано стохастичну природу надходження вагонів у пункти накопичення та дотримання составів до встановленої норми. При моделюванні вважається, що колійний розвиток залізничних станцій та внутрішньовузлових ходів є раціональним, та несуттєво впливає на затримку руху передавальних поїздів. Графік руху передавальних поїздів є раціональним та ритмічним. Пропускна спроможність перегонів вузла та переробна спроможність підсистем залізничних станцій є достатніми.Експериментально проведено порівняння ефективності чотирьох моделей організації передавальних поїздів, у тому числі «гнучкою моделлю», яка поєднує відправлення за накопиченням до норми состава і «жорстким графіком» одночасно. Встановлено, що мінімальні вагоно-години накопичення досягаються при організації передавальних поїздів комбінованим варіантом: одночасне відправлення і за «жорстким графіком» і накопиченням до норми. Результат експерименту виявив найбільш ефективний варіант організації передавальних поїздів, а саме комбінований варіант. Даний варіант передбачає, що при наявності достатньої кількості вагонів у пункті накопичення поїзд відправляється раніше (відправлення за накопиченням до норми), інакше – через розрахунковий середній інтервал (варіант відправлення за «жорстким графіком»). Організація передавальних поїздів за «жорстким графіком» потребує організації додаткових поїздів, інакше суттєво зростає черга із вагонів у пунктах накопичення. При збільшенні добової кількості поїздів на 10–11 % процес формування та відправлення стає достатньо надійним та ефективним.Зазначенні рекомендації дозволять удосконалити типовий процес роботи залізничних вузлів у частині диспетчерського контролю за формуванням, відправленням та пропуском передавальних поїздів у внутрішньовузловому сполученні

A slow driving vehicle within traffic flow is considered as a moving bottleneck (MB). In this paper, we present simulations made with a microscopic stochastic flow model with a moving bottleneck in the framework of the three-phase theory by Kerner. The goal is to predict traffic phenomena that may occur if traffic breakdown is realized at the moving bottleneck. Considered is a traffic flow in which different percentages of probe vehicles are randomly distributed, which send their position and their speed each second (simFCD). We investigate what percentage of probe vehicles is necessary to reliably detect a moving bottleneck and predict its motion.

In this paper, we investigate system reliability optimization of multi-source multi-sink flow networks subject to transmission budget constraints. More specifically, we present a mathematical model of the optimization problem and a genetic algorithm (GA) to solve it. The GA is based on determining the optimal set of lower boundary points that maximize system reliability such that transmission cost does not exceed a specified upper bound. Finally, to ensure the efficiency of our approach, we apply our proposed algorithm to various network examples.