Problems of restoration and development of urban environment of old industrial centers]

The paper considers the urban development and reconstruction of industrial centers on the example of different cities. Design proposals are given for the renovation of the Russian factories and landscaping of industrial historic cities. Examples are given for the reconstruction of silk weaving enterprises near Moscow. Many factories are now in a derelict condition, and for the normal urban development need revitalization of enterprises and comprehensive improvement of adjacent areas. Thanks to the development of cloth production, small settlements in central Russia became industrial city-forming centers more than two hundred years ago. Small manufactories were transformed into large industrial complexes, and the unique exquisite fabrics surpassed the best European ones in price and quality. Russian fabrics were universally welcomed at international exhibitions, awarded with medals and long-term orders. Cities were growing, the economy was developing, housing construction helped to solve social problems, transportation and infrastructure of cities and settlements were developing. Early in the 21st century, glorious weaving factories became an integral part of historic cities, their decoration and pride. Architectural ensembles of industrial enterprises became not only monuments of the Russian cultural heritage, but also an important component of the Russian cities.

University science. Internal possibilities of stimulating scientific activity in Russian universities

The statistics of research funding are reviewed, the experience of organizing research activities in Russian universities is summarized, and a model of its system support is proposed by the university itself. It is stated that in university science there is a “customer crisis”: the demand of the business sector does not provide the necessary volume of large and long-term orders for scientific research and studies rely mainly on the state budget. Organizational measures are proposed for a gradual transition from teaching to research with step-by-step confirmation of productivity: the creation of a new university subject – a “scientific unit” consisting of two or more employees, regardless of their academic title, with administrative rights and corresponding responsibility.

The Environmental Effect of Radioactive Particles in the Contaminated Sites with Resuspended Plutonium Aerosols

The plutonium material within the nuclear devices would be aerosolized and cause intense respirable hazards in the scenes of nuclear test and nuclear accident. The assessment of plutonium aerosol resuspension according to the typical radioactive contaminated sites would provide instructional data for the resuspended aerosol fluctuation study and edaphic cleanup, which can remedy the uselessness of aerosol diffusion model in the study of plutonium contaminated regions. The empirical model of plutonium aerosol resuspension is based on the aerophysics, the geognosy and the radiochemistry. This method was applied to analyze the representative plutonium contaminated regions. The results indicate that soil erosion is the intrinsic factor of resuspension process. The resuspended concentrations of plutonium aerosols in nuclear test sites are much less severe than those in the “non-nuclear” test sites (safety shots and simulated nuclear accident tests). Short-term, orders-of-magnitude fluctuations of the airborne concentrations are observed due to the natural and man-made disturbances. After systematic soil cleanup the resuspended plutonium aerosol concentration could fall down to the public allowable level.

Predicting Short-Term Orders by an Improved Grey Neural Network Model

According to the validation that the random selection of the gray neural network parameters random selection is similar to initial the space position of the particle in the particle swarm algorithm, the gray neural network based on the modified particle swarm optimization (PSO) algorithm is established to improve the robustness and the precision of the net model with applying a improved PSO algorithm to instead of gradient correction method, updating the network parameter and searching the best individual in this algorithm. There are several methods to forecast the short-term orders, including BP, the gray network, the original PSO algorithm and the improved PSO algorithm. Comparing with these methods, the results demonstrated the grey network based on the improved PSO algorithm has better approximation ability and prediction accuracy.

Toric Ideals of Flow Polytopes

International audience We show that toric ideals of flow polytopes are generated in degree $3$. This was conjectured by Diaconis and Eriksson for the special case of the Birkhoff polytope. Our proof uses a hyperplane subdivision method developed by Haase and Paffenholz. It is known that reduced revlex Gröbner bases of the toric ideal of the Birkhoff polytope $B_n$ have at most degree $n$. We show that this bound is sharp for some revlex term orders. For $(m \times n)$-transportation polytopes, a similar result holds: they have Gröbner bases of at most degree $\lfloor mn/2 \rfloor$. We construct a family of examples, where this bound is sharp. Nous démontrons que les idéaux toriques des polytopes de flot sont engendrés par un ensemble de degré $3$. Cela a été conjecturé par Diaconis et Eriksson pour le cas particulier du polytope de Birkhoff. Notre preuve utilise une méthode de subdivision par hyperplans, développée par Haase et Paffenholz. Il est bien connu que les bases de Gröbner revlex réduite du polytope de Birkhoff $B_n$ sont au plus de degré $n$. Nous démontrons que cette borne est optimale pour quelques ordres revlex. Pour les polytopes de transportation de dimension $(m \times n)$, il existe un résultat similaire : leurs bases de Gröbner sont au plus de degré $\lfloor mn/2 \rfloor$. Nous construisons une famille d'exemples pour lesquels cette borne est atteinte.

Updown Numbers and the Initial Monomials of the Slope Variety

Let $I_n$ be the ideal of all algebraic relations on the slopes of the ${n\choose2}$ lines formed by placing $n$ points in a plane and connecting each pair of points with a line. Under each of two natural term orders, the ideal of $I_n$ is generated by monomials corresponding to permutations satisfying a certain pattern-avoidance condition. We show bijectively that these permutations are enumerated by the updown (or Euler) numbers, thereby obtaining a formula for the number of generators of the initial ideal of $I_n$ in each degree.

Standard Paths in Another Composition Poset

Bergeron, Bousquet-Mélou and Dulucq [Ann. Sci. Math. Québec 19 (1995), 139–151] enumerated paths in the Hasse diagram of the following poset: the underlying set is that of all compositions, and a composition $\mu$ covers another composition $\lambda$ if $\mu$ can be obtained from $\lambda$ by adding $1$ to one of the parts of $\lambda$, or by inserting a part of size $1$ into $\lambda$. We employ the methods they developed in order to study the same problem for the following poset, which is of interest because of its relation to non-commutative term orders : the underlying set is the same, but $\mu$ covers $\lambda$ if $\mu$ can be obtained from $\lambda$ by adding $1$ to one of the parts of $\lambda$, or by inserting a part of size $1$ at the left or at the right of $\lambda$. We calculate generating functions for standard paths of fixed width and for standard paths of height $\le 2$.

A Poset Classifying Non-Commutative Term Orders

International audience We study a poset $\Re$ on the free monoid (X*) on a countable alphabet X.This poset is determined by the fact that its total extensions are precisely the standard term orders on X*. We also investigate the poset classifying degree-compatible standard term orders, and the poset classifying sorted term orders. For the latter poset, we give a Galois coconnection with the Young lattice.