Virtual approach to holonic control of the tyre-manufacturing system

Tyre manufacturers aiming to remain competitive in complex modern markets must promptly adjust to the changes within the production environment. With traditional tyre-manufacturing systems, a slow response during optimization of the manufacturing process and low-level adaptability to system disturbances is evident. The presented approach to virtual holonic control of the tyre-manufacturing system enables dynamic response in the event of new optimization demands, decrease of the impact of disturbances on system productivity and smaller future investments in the manufacturing equipment.     

Investigation of the cold orbital forging process of an AlMgSi alloy bevel gear

Orbital forging is a metal forming process in which one of the dies performs a complex rocking motion. It ensures reduction in required load and allows for the cold forming of a workpiece. One of the mechanical parts formed by means of this technology is a bevel gear. However, a numerical analysis of orbital forging bevel gears is very difficult to perform due to the complex rocking motion of the die, which is confirmed by numerous works investigating the orbital forging process. In the present work, investigation results of the cold orbital forging of aluminum alloy bevel gears are presented. In contrast to other works devoted to the process, this study proposes a new procedure for forming bevel gears and the workpiece used has a shape which is different from the previously applied ones. The obtained results apply to both theoretical and technological aspects of orbital forging. The FEM simulation results have been successfully verified in laboratory conditions using the industrial PXW-100A press.     

The Influence of Disorder on Thermotropic Nematic Liquid Crystals Phase Behavior

We review the theoretical research on the influence of disorder on structure and phase behavior of condensed matter system exhibiting continuous symmetry breaking focusing on liquid crystal phase transitions. We discuss the main properties of liquid crystals as adequate systems in which several open questions with respect to the impact of disorder on universal phase and structural behavior could be explored. Main advantages of liquid crystalline materials and different experimental realizations of random field-type disorder imposed on liquid crystal phases are described.     

Composition and submicron structure of thin films of supersaturated Zn x Pb1 − x S solid solutions

Thin films of supersaturated Zn _x Pb_{1 ? x} S solid solutions containing up to 4.1 mol % ZnS have been obtained by hydrochemical deposition. The dependence of the material structure and surface morphology on the film composition has been studied. It is established that an increase in the content of zinc sulfide leads to the growth of grains with a more complicated crystalline structure, the formation of grain boundary fragments with dimensions from 60 to 100 nm, and a modification of the electrical properties of deposited layers.     

First Principles Investigation of Local Distortions in Doped La2CuO4

We present the results of first-principles cluster calculations of local distortions in doped La₂CuO₄. Local deformations of the CuO₆ octahedra associated with the presence of an additional extrinsic hole were determined using the density-functional (DF) method on various cluster models. The results indicate that a localized hole induces a contraction of the CuO(apical) distance from 2.40 to 2.28 Å. The contracted distance is in very good agreement with the anomalous, short CuO(apical) distance of 2.3 Å, observed recently by polarized Cu K-edge extended x-ray absorption fine structure (EXAFS) in La_1.85Sr_0.15CuO₄ and associated with the hole-rich stripe region.     

Functional morphology of nucleolus organizer regions of chromosomes and nucleoli in human multiple myeloma cell lines. I. Variation of the morphology and silver staining of nucleolus organizer regions of chromosomes in RMPI 8226 and U 266 cell lines with different level of differentiation of during 7 days after cell passage

The morphology and Ag-staining of nucleoli in human multiple myeloma cell lines RPMI 8226 and U 266, distinguished from each other in the differentiation degree, were quantitatively studied, and the production of immunoglobulins or their fragments by the line cells was evaluated throughout 7 days after cell seeding. The less differentiated cell line RPMI 8226 and the high differentiated cell line U 266 were revealed to differ in both the initial level of immunoglobulin production and dynamics of immunoglobulin accumulation in culture medium. The total number of Ag-stained nucleolar-organizer regions (AgNORs) per nucleus in cells RPMI 8226 was significantly higher than in cells U 266 in all times after seeding of the cells. In both cell lines changes in the quantity and shape of nucleoli and also in the total number of AgNORs per nucleus and pattern of AgNORs distribution within nucleoli correlated with the cell cycle phase. Relationships between morphofunctional changes in nucleoli and the differentiation degree and proliferative activity of the cells, and also between the number of Ag-positive nucleolar-organizing metaphase chromosomes and the functional activity of interphase AgNORs are discussed.     

The intracellular mechanisms of glutaminergic and cholinergic signal transduction in the cerebral cortex

Stimulation of glytamate- and cholinoreceptors by the agonists induced a prolonged calcium and phosphoinositide responses to short-term anoxia or administration of an antioxidant agent in cortical structures. Processes of adaptation essentially modified these responses.     

可靠性和维修性——现代设计的关键因素（二）

2.3可靠性维修性的定量分析方法现代设计过程设计到多种学科,其目的是获得合理的市场价格、性能和功能性。目前绝大多数设备说明书中都包含有一个报告,其中定义了预期的系统效率或可用性,一般来说,系统的可用性可以这样计算:A=总的可用总时的间可-用实时际间停机时间=MTTMRT BM     

Local amorphization of atomic structure in Mg<Subscript>0.54</Subscript>Zn<Subscript>0.46</Subscript>Fe<Subscript>2</Subscript>O<Subscript>4</Subscript> ferrites

The structure of Mg_0.54Zn_0.46Fe₂O₄ ferrites has been studied using x-ray diffraction techniques. It is established that high-temperature annealing (T = 1280°C, τ = 0.5–8.0 h) leads to a change in the crystal structure of samples, which is accompanied by their local amorphization.