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The problem of optimal control of traffic flows in the urban road network is considered. To describe the traffic flows, a universal recurrent finite-difference model based on the theory of controlled networks is used. Using a variational genetic algorithm, the optimal admissible traffic light control program is obtained. The sensitivity of the found optimal admissible control to changes in the throughput of manoeuvres, flow distributions, the initial state of the network is experimentally investigated.

This article presents the study of evolutionary computations for optimization of traffic lights signals at intersections in urban areas. Evolutionary algorithm is applied to universal recurrent traffic flow model. The outcome of optimization process is a control program that regulates the traffic lights depending on the flow state at road sections. The influence of some parameters of algorithm on convergence are studied.

The article considers a hybrid recurrent mathematical model of traffic flow control, that consists of two types of models: a universal recurrent finite-difference model for describing subnetworks with known parameters, and a model based on the artificial neural networks to describe subnetworks with partially unknown parameters. The choice of Elman recurrent neural network is substantiated and a method for its training based on a variational genetic algorithm is described.

The East Asian tree Ulmus japonica (Rehder) Sarg. is a nemoral relict species for Western Transbaikalia (See Fig. 1). A few localities of this tree are known in the region, those in the lower reaches of the Selenga River (Yugovo site; Republic of Buryatia) and the Chikoy River (Zhindo site; Zabaikalskii Krai), remote from the main distribution area (See Fig. 2). The study aimed to verify the distribution of U. japonica and to estimate the value of U. japonica communities for biodiversity conservation in the region. Based on the data collected, we discussed some opportunities and suggested approaches for the protection of these unique ecosystems. During the fieldwork in 2018 and 2019, we studied all known localities of U. japonica in Western Transbaikalia and revealed a pleiad of new locations within the site Yugovo as well as a new location (the site Murochi) in the Chikoy River valley within the Republic of Buryatia (See Fig. 2 and 3). Information on the occurrence of U. japonica in the vicinity of Podlopatki village (in the Khilok River valley) was not confirmed. Also, our attempts to find this species at the site within the Barguzin River valley according to the label of the existing herbarium specimen failed. Based on 93 relevés, we examined species composition in woodlands where U. japonica is a codominant species and revealed the main features and peculiarities of the communities in the region. At all sites, monodominant coppices of U. japonica and coenoses where it is mixed with Padus avium Mill. occurred. Nevertheless, Ulmus japonica communities from the site Yugovo differ from those of Zhindo and Murochi in a greater phytocoenotic diversity and the composition of characteristic plant species. Additionally, at Yugovo rather xeromesophytic sparse communities where U. japonica is mixed with Pinus sylvestris L. and Betula platyphylla Sukaczev were found. Characteristic species of shrub and herbal layers at Yugovo site are Carex arnellii Christ ex Scheutz, Circaea lutetiana L., Elymus pendulinus (Nevski) Tzvelev, Festuca extremiorientalis Ohwi, Filipendula palmata (Pall.) Maxim., Hesperis sibirica L., Lamium album subsp. orientale Kamelin & A.L. Budantzev, whereas at Zhindo and Murochi they are Anemonidium dichotomum (L.) Holub, Carex sordida Van Heurck & Müll. Arg, Menispermum dauricum DC., Rhamnus davurica Pall., and Rubia cordifolia L. According to our studies supplemented with data from the literature sources, there are 16 species of vascular plants, lichens, beetles, and lepidopterans registered in Ulmus japonicaforests that are included in the Federal and/or in regional Red Data Books (See Table 1). We have revealed 31 additional rare and relict species of plants, fungi and insects (See Table 2). In total, 19 species were found in Western Transbaikalia or within this plant community type for the first time. The newly revealed rare and relict species could be recommended for listing in the regional Red Data Book or inclusion in the list of species of special surveillance. As a perspective of the protection of communities with U. japonica, we propose to maintain them as distinct clusters under the management of the existing protected areas. Namely, the site Yugovo can be protected as a separate cluster of the Baikal Natural Reserve, likewise, the protection of the site Zhindo can be managed by the Chikoy National Park. The newly discovered site Murochi might be included in the preliminarily proposed Russian-Mongolian trans-boundary Selenga protected area.

Frullania usamiensis is recorded for the first time for Russia from Kunashir Island, the southernmost island of the Greater Kuril Chain. It is the northernmost locality of the species, which was previously known from Japan (Honshu, Shikoku and Kyushu), China (coastal provinces Fujian and Liaoning) and the Republic of Korea. Frullania usamiensis is distinguished by (1) relatively large, emarginate or shallowly bilobed underleaves with obtuse lobes and mostly rounded sinus, (2) characteristic leaf lobules which are transversely elongated (when inflated), about × 1.5–1.9 as wide as long, with incurved rostral portion, and (3) smooth perianth with three keels. Description and photomicrographs of F. usamiensis from Kunashir Island are provided together with discussion on its ecology, variation and differentiation from having much in common F. kagoshimensis and F. taradakensis.

The paper continues the study of symbolic regression methods for control learning. The optimal control problem with phase constraints for a group of robots is considered. To solve the problem, the method of synthesized optimal control is used. At the first stage the stabilization problem is solved for each robot. Using a new hybrid evolutionary algorithm, built on the basis of the genetic algorithm, the particle swarm optimization and the gray wolf optimizer, stable equilibrium points are found. Next, the original optimization problem by piece-wise linear approximation of the equilibrium points is solved. In contrast to the known methods for solving the synthesis problem, the control learning by the complete binary genetic programming is used. The advantage of this approach is that the resulting control is realizable on board of mobile robots. Simulation is given for a group of two mobile robots.

Two approaches to the numerical solution of the optimal control problem are studied. The direct approach is based on the reduction of the optimal control problem to a nonlinear programming problem. Another approach is so-called synthesized optimal control, and it includes the solution of the control synthesis problem and stabilization at some point in the state space, followed by the search of stabilization points and movement of the control object along these points. The comparison of these two approaches was carried out as the solution of the optimal control problem as a time function cannot be directly used in the control system, although the obtained discretized control can be embedded. The control object was a group of interacting mobile robots. Dynamic and static constraints were included in the quality criterion. Implemented methods were evolutionary algorithms and a random parameter search of piecewise linear approximation and coordinates of stabilization points, along with a multilayer network operator for control synthesis.

This paper presents a universal recurrent traffic flow model designed to simulate traffic flows and solve the problem of finding the optimal durations of traffic light phases. The model belongs to the class of microscopic and is based on the theory of controlled networks. The road network is presented as a configurable graph. The nodes of the graph are the road sections, and the edges are the maneuvers between the sections. The graph configuration is changed by turning the graph edges on or off, which corresponds to the permission or prohibition of certain maneuvers. Traffic flows are controlled by traffic lights at regulated intersections. To apply this model it is assumed that the information about the parameters of flows and the road network is available. The description of the model, its properties, and a methodological example of calculation are given.

A numerical method based on the Pontryagin maximum principle for solving an optimal control problem with static and dynamic phase constraints for a group of objects is considered. Dynamic phase constraints are introduced to avoid collisions between objects. Phase constraints are included in the functional in the form of smooth penalty functions. Additional parameters for special control modes and the terminal time of the control process were introduced. The search for additional parameters and the initial conditions for the conjugate variables was performed by the modified self-organizing migrating algorithm. An example of using this approach to solve the optimal control problem for the oncoming movement of two mobile robots is given. Simulation and comparison with direct approach showed that the problem is multimodal, and it approves application of the evolutionary algorithm for its solution. Web of Science 8 12 art. no. 2105

The results of detailed long-term studies of the hepatic flora of the Dzherginsky Reserve, performed in 50 collection points throughout the reserve, in the forest, sub-headland and tundra zones are presented. There are 125 species and 4 varieties, including new for Baikal Siberia Lophoziopsis excisa var. elegans, Mannia pilosa, Mesoptychia rutheana and Odontoschisma denudatum and new for Buryatia Blepharostoma trichophyllum var. brevirete, Cephaloziella uncinata, Frullania davurica, F. muscicola, Fuscocephaloziopsis loitlesbergeri, Jungermannia exsertifolia, J. cf. polaris, L. pellucida, Mesoptychia badensis, M. sahlbergii, Neoorthocaulis hyperboreus, Odontoschisma elongatum, Pellia endiviifolia, Plagiochila arctica, Plectocolea obscura, Sauteria alpina, Scapania brevicaulis, S. rufidula, Schljakovianthus quadrilobus. The analysis of the flora with emphasis on the altitudinal species distribution is provided.

This paper presents a comparative study of synthesis methods for real-time control of an unmanned car-like mobile robot while moving along a given trajectory. Three methods are considered: a feedback control using the PID controller, a model predictive control, and artificial neural networks. A comparison is based on computational experiments. A complex trajectory with crossing paths is considered for path tracking.

A paper considers a synthesized optimal control problem. To solve this problem, it is necessary to solve the problem of control system synthesis for stabilization of control object relatively a point in the state space, and then to solve the second problem of optimal control to find some stabilization points for movement from initial position to terminal one with the best value of the quality criterion. For the first problem a network operator method was used. It finds a mathematical expression of a feedback control system in the form of oriented calculating graph by evolutionary algorithm. For solution of the second problem a particle swarm optimization was applied. In experiment the control object is a pair of robots that move a cart joined by rigid hinged hitch from initial point to terminal one trying to avoid obstacles.

This paper is addressed to application of SOMA to the optimal control problem of a group of objects with static and dynamic phase constraints. The optimization problem is not convex and unimodal. In the practical part a synthesized optimal control problem is considered. Firstly, it is necessary to solve a control synthesis problem to stabilize each object relatively a point on the state space. To solve the synthesis problem a network operator method was used. For each control object the coordinates of some stabilization points were found. While moving from point to point in given time interval all objects reach their terminal states without violation of constraints and with optimal quality criterion. A modified SOMA is proposed for the search of stabilization points.

Optimization problems and their solution by symbolic regression methods are considered. The search is performed on non-Euclidean space. In such spaces it is impossible to determine a distance between two potential solutions and, therefore, algorithms using arithmetic operations of multiplication and addition are not used there. The search of optimal solution is performed on the space of codes. It is proposed that the principle of small variations of basic solution be applied as a universal approach to create search algorithms. Small variations cause a neighborhood of a potential solution, and the solution is searched for within this neighborhood. The concept of inheritance property is introduced. It is shown that for non-Euclidean search space, the application of evolution and small variations of possible solutions is effective. Examples of using the principle of small variation of basic solution for different symbolic regression methods are presented.

Some common properties of violation of object function unimodality in optimal control problems are considered. Phase constraints and control object models for special symmetric systems are considered. It is shown that for a control problem of a group of objects, given in the form of a symmetric system of equations, for certain initial and terminal conditions the functional is not unimodal. It is claimed that for optimal control problems with non-unimodal functionals it is efficient to use evolutionary algorithms. An example of an optimal control problem for a group of symmetric objects with phase constraints resolved by evolutionary and gradient algorithms is provided.

The problem of monitoring of some area by means of mobile robots is considered. In the stated problem we assume that the area with obstacles is given and randomly located marks are also given. The control object has the field of viewing. It is necessary to find the optimal control, which will move the robots from the initial state to the terminal state for a given time and scan as many marks as possible. To solve the task the evolutionary algorithm of grey wolf optimizer is used.

This study provides the first record of Bathysolen nubilus (Fallen, 1807) for the Republic of Buryatia (Russian Federation) and extends the known distribution of this species eastward in the Palaearctic region. Bathysolen nubilus is the only species of its genus that occurs in Eurasia. Specimens of B. nubilus were captured in dry grass meadows and forest edges located along the lower reach of the Selenga River. Data and figures of B. nubilus for the recognition of the species, as well as a map of collecting localities, are presented.

In 2013 the monotypic genus Ascidiota C.Massal. was found in the Republic of Buryatia and the Taymyr District of Krasnoyarsk Territory, Russia. These are the most northerly known localities for Ascidiota. An illustration, distribution map and complete description of A. blepharophylla C.Massal. are provided. Variation, differentiation, and distribution of A. blepharophylla are discussed. A key to distinguish Ascidiota from morphologically similar species of the genera Porella L. and Frullania Raddi is presented. Sequences of nrITS1–5·8S–ITS2 were identical in plants from Buryatia and Alaska. This supports the hypothesis of the integrity of this monotypic genus. Inadequate bryological exploration of many northern territories suggests that the list of Ascidiota records, especially in north Asia, will be extended in the future.

WOS: 000348594500007, …, Institute of Environmental Technologies - 'Research and Development for Innovations' Operational Programme [CZ.1.05/2.1.00/03.0100]; Structural Funds of the European Union; state budget of the Czech Republic; National Feasibility Programme I of the Czech Republic [LO1208]; SYNTHESYS project [FR-TAF-3686]; University of Ostrava [SGS27/PRF/2014]; Polish National Centre of Science [N N 303 469 338]; Institute of Botany of the Polish Academy of Sciences; Institute of Biology Bucharest of the Romanian Academy [RO1567-IBB03/2014]; Natural Environment Research Council; Scientific and Technological Research Council of Turkey (TUBITAK) [111T359]; Spanish Ministerio de Economia y Competitividad (MINECO); Flora Briofitica Iberica from MINECO [CGL2009-09530]; MINECO; Spanish 'Ministerio de Ciencia e Innovacion' [CGL2010-15959, CGL2009-07323]; FEDER; 'Ramon y Cajal' Subprogram (MICINN-European Social Fund); 'Ministerio de Economia y Competitividad' [CGL2012-30721]; MOVECLIM project (ANR under the Net-Biome call); RSF [14-14-00903, 14-24-00037]; RFBR [13-04-01427, 12-04-01476]; 'The Survey of new and unrecorded taxa in vascular plants (NIBR)' - Ministry of Environment of the Korean Government [2013-02-001]; Natural Environment Research Council [bas0100025], The contribution by V. Plasek is part of a research project of the Institute of Environmental Technologies, reg. no. CZ.1.05/2.1.00/03.0100, supported by the 'Research and Development for Innovations' Operational Programme, and financed by the Structural Funds of the European Union and by the state budget of the Czech Republic, Project LO1208 of the National Feasibility Programme I of the Czech Republic, and SYNTHESYS project FR-TAF-3686. The contribution by L. Cihal is a part of grant project SGS27/PRF/2014 financed by University of Ostrava. The contributions by R. Ochyra have been financially supported by the Polish National Centre of Science through grant no. N N 303 469 338 and, in part, by the statutory fund of the Institute of Botany of the Polish Academy of Sciences. He also thanks Helen J. Peat, Cambridge, for kindly allowing him to study the herbarium collections from AAS. S. Stefanut, acknowledges the support by project no. RO1567-IBB03/2014 through the Institute of Biology Bucharest of the Romanian Academy. J. Vana and K. K. Newsham acknowledge the logistics support that was provided by the British Antarctic Survey's Operations Group, officers and crew of the RRS Ernest Shackleton and staff at King Edward Point research station, and thank Helen J. Peat for the loan of AAS herbarium specimens. Funding was provided by the Natural Environment Research Council. All are gratefully acknowledged.; Peter Szucs and Andras Bidlo would like to thank Peter Erzberger for examining the specimen of Campylopus introflexus, and Gyorgy Pulger for his assistance in fieldwork. Tulay Ezer and Recep Kara are indebted to the Scientific and Technological Research Council of Turkey (TUBITAK) for financial support (Project Code: 111T359).; M. J. Gil-Lopez, F. Puche, and J. G. Segarra-Moragues thank H. Kharbouch (SahaTours), F. Pacheco, J. P. Peralta, and F. Rivera for their help in field work. M. J. Gil-Lopez benefited from a FPU PhD grant from the Spanish Ministerio de Economia y Competitividad (MINECO). F. Puche acknowledges funds from project CGL2009-09530, Flora Briofitica Iberica from MINECO. J. G. Segarra-Moragues benefited from a 'Ramon y Cajal' post-doctoral contract from MINECO. Juan Larrain and Amalia B. Biasuso thank Reinaldo Vargas and Gotz Palfner for their company in the field. Marta Alonso and David Long acknowledge the financial support of the Spanish 'Ministerio de Ciencia e Innovacion' (projects CGL2010-15959 co-financed by FEDER) and 'Ramon y Cajal' Subprogram (MICINN-European Social Fund). We also thank Maria J. Cano and Juan A. Jimenez for their contribution to this work.; D. Rios, M. T. Gallego, and J. Guerra are grateful to Len Ellis for organising the loan of specimens and assistance during the visit of the first author to the BM herbarium. This research was carried out with financial support from the Spanish 'Ministerio de Ciencia e Innovacion' and 'Ministerio de Economia y Competitividad' [Projects CGL2009-07323 and CGL2012-30721, respectively].; Terry Hedderson is grateful to Jean-Yves Meyer, Ravahere Tuputuari, Claudine Ah-Peng, and Oliver Flores for field assistance and companionship and to the MOVECLIM project (ANR under the Net-Biome call) for funding the fieldwork on Tahiti. The study by E.V. Sofronova was supported by RSF (project no. 14-14-00903), that by Y.S. Mamontov was partly supported by RFBR (project no. 13-04-01427 and 12-04-01476), and that by A. D. Potemkin was supported by RSF (project no. 14-24-00037). The research by Yoon Young-Jun, Benito C. Tan and Byung-Yun Sun was supported by grants from 'The Survey of new and unrecorded taxa in vascular plants (NIBR No. 2013-02-001)' funded by the Ministry of Environment of the Korean Government.