The Fermat-Torricelli problem in the case of three-point sets in normed planes

In the paper the Fermat-Torricelli problem is considered. The problem asks a point minimizing the sum of distances to arbitrarily given points in d-dimensional real normed spaces. Various generalizations of this problem are outlined, current methods of solving and some recent results in this area are presented. The aim of the article is to find an answer to the following question: in what norms on the plane is the solution of the Fermat-Torricelli problem unique for any three points. The uniqueness criterion is formulated and proved in the work, in addition, the application of the criterion on the norms set by regular polygons, the so-called lambda planes, is shown.Comment: 13 pages, 9 figure

Flotation extraction of elemental sulfur from gold-bearing cakes

Currently, in the development of the raw materials base of the gold mining industry, there is a tendency to reduce the quality of the initial mineral raw materials due to the depletion of reserves of rich gold-bearing ores. The article discusses the technology of extraction of refractory gold-bearing concentrates based on low-temperature leaching of pyrite concentrate. A decrease in the parameters of the autoclave oxidation of sulfide minerals, such as pyrite and arsenopyrite, leads to the incomplete extraction of gold into the solution and, consequently, its losses during subsequent cyanidation. As a possible option for a more complete extraction of gold using low-temperature oxidation technology, a method of flotation separation of elemental sulfur from leaching cakes is proposed. According to the basic process flow chart, the flotation process designed for gold extraction is carried out after autoclave oxidation, but before cyanidation. A series of experiments were carried out with varying reagent conditions and the dependence of gold losses on the extraction of elemental sulfur in the flotation tailings was established. As determining factors, pH and solid content in the initial pulp were considered. The paper justifies the separation of elemental sulfur from autoclave cake to enriched sulfur concentrate. The cake flotation modes after autoclave oxidative leaching of pyrite concentrate are investigated. The distribution of elemental sulfur and gold by flotation products makes it possible to conduct the tailings cyanidation process with acceptable indicators

Modernized algorithm of neural network initial weighting factors during the diagnosis of diesel engine faults

© Research India Publications. A lot of knowledge and experience is required in order to perform diesel fault diagnosis from an expert. However, one should not rule out the “human factor”, the expert may forget something or miss some important facts during analysis. In order to assist an expert during the analysis of diesel engine faults the task of an expert system development becomes a relevant one. It is advisable to develop this system based on an artificial neural network, which allows to classify diesel faults. The application of an artificial neural network for solving this class of problems makes it possible to reduce the volume of stored data through the creation of a weight factor knowledge base and to carry out a refinement of this base through training if necessary, which allows to improve the accuracy of clustering, as well as to change the network structure easily if new types of faults appear. The modernized method is based on the appointment of an input vector data as the initial weighting coefficient which is encountered first in each cluster group. The effectiveness of the modernized algorithm concerning the selection of initial weighting factors prior to existing ones is in the significant reduction of training cycle number, reducing the load on processing devices. The greatest effect may be achieved at a large number of training samples, and the dimension of an input and an output vector

Studies of the Composition of the Cell Antigen Preparations Obtained from Pathogenic Burkholderia, Using Immunoblotting

Carried out has been comparative analysis of the cell antigen immune-electrophoregrammes of B. pseudomallei C-141, B. mallei 10230, B. thailandensis 264, and B. cepacia 25416 after immunoblotting with immune rabbit sera to living cells of avirulent B. pseudomallei 107, celllular and extracellular antigens of B. pseudomallei 107, B. pseudomallei C-141, B. mallei 10230, B. thailandensis 264, and B. cepacia 25416. Visual investigation has revealed the presence of fractions with molar mass of 18.4 and 35 kDa in B. malei 10230 cell antigens’ electrophoregramme obtained by means of immunoblotting with serum to B. malei 10230 cell antigens, as distinct from B. pseudomallei C-141 electrophoregramme with the same serum. This makes it possible to distinguish the pathogenic Burkholderia. At the same time utilization of heterologous immune sera enhances discriminating capacity of the comparative assay. The level of reproducibility of immune-electrophoregrammes allows for the deployment of the similarity coefficient for computer-based comparative analysis

Method for complex web applications design

© Research India Publications. This article deals with peculiarities of design that are taken into consideration during practical development of complex information systems, made on the basis of web technologies, in particular during development of web applications. This article covers the majority of development aspects from the position of different methodologies of web applications design and lists design peculiarities differences in comparison with programme means that do not use web technologies. Web application architecture design according to block and modular principle is suggested. The main programme block will be responsible for users’ authorization, session provision, request of enclosed modules, connection to database and similar service functions. Administrative module will allow managing sets of modules, features of web applications, change informational content. It is also suggested that services of web application are designed according to modular principle as the ones that have their own managing modules and modules of data processing (working modules). Peculiarity of the suggested methodology is that the modules are made in the form of separate files that execute their own specific function and work strictly with their own tables in database. It is suggested to use traditional approach when creating a web application. It is connected with presence of a big number of different relational database control systems supported by web servers. Initially on the stage of database design datalogical models are being developed. They are oriented on data storage and processing environment. The difference of the suggested graphic interface is that navigation in the web application is managed by the user who may execute previously permitted actions on random following his way in navigating the interface. The method described in the article is used in web applications development for automated informational systems of diesel engines trials

ROC-Analysis of the Results as regards <I>B. pseudomallei</I> and <I>B. mallei</I> Agents Detection Using Solid-Phase ELISA

Analyzed are operational characteristic curves (ROC-curves) of solid-phase ELISA variants with immune sera to cellular and extracellular Burkholderia antigens with the aim to determine the most effective ones for B. pseudomallei and B. mallei antigen detection. It is shown that among solid-phase ELISA variants with immune sera to cellular and extracellular antigens, those with sera to homologous antigens are the most effective. Demonstrated is the possibility of application of solid-phase ELISA variants with immune sera to antigens of B. thailandensis and B. cepacia strains for identification and typing of glanders and melioidosis agents. Assessed are prospects of extracellular antigen application for differentiation between closely related species of “ pseudomallei ” group

Analysis and Monitoring of the Environment in the Framework of the Ecosystem Approach

Рассмотрены возможности применения статистических методов мониторинга показателей экологической статистики в рамках экосистемного подхода. Построены регрессионные модели взаимосвязи и влияния: накопления производственных и бытовых отходов и их утилизацией и обезвреживанием. Сделаны выводы о необходимости использования моделей мониторинга экологической информации.The possibilities of using statistical methods for monitoring environmental statistics indicators in the framework of the ecosystem approach are considered. Regression models of interrelation and influence are constructed: accumulation of industrial and household waste and their disposal and neutralization. Conclusions are drawn about the need to use models for monitoring environmental information

Proven and less studied hematopoietic and vasoactive growth factors in retinal capillary hemangioma

Pathogenesis of retinal capillary hemangioma has not been sufficiently studied at the present time. Therefore, the study of cytokine levels in biological fluids seems to be very relevant in order to increase knowledge about the mechanisms of the disease development and searching for targeted therapies. The content of hematopoietic and vasoactive growth factors in blood serum, lacrimal fluid, and vitreous body was studied in patients with retinal capillary hemangioma. A total of 26 patients with retinal angiomatosis were examined. The samples of blood serum (n = 23) and lacrimal fluid (n = 10) from practically healthy people aged 22 to 46 (27.4±1.4 years) were used as a control. To perform comparative assessment of cytokine concentrations in the vitreous body of patients with retinal capillary hemangioma, were used samples of the vitreous body from 6 patients (average age 33±4.7 years; from 21 to 49 years) with rhegmatogenous retinal detachment. To measure the cytokine concentrations, we applied multiplex analysis technique using the xMAP platform with LuminexxPONENT 3.1 program and ProcartaPlex sets (eBioscience, Austria). A detailed characteristic of vasoactive factors in capillary retinal hemangioma was obtained as a result of this work. Some disorders in chemokine regulation were identified. There was a significant increase in serum concentrations of three vasoactive factors, i.e., PDGF-BB, HGF, and PIGF-1, with a decrease in chemokines (MCP-1, MIP-1α, and MIP-1β). The frequencies of PIGF-1 and MIP-1α detection also significantly differed from the control group. SCF was significantly more often determined in patients with retinal angiomatosis only at the systemic level. Correlations between PDGF-BB and PIGF-1, as well as PIGF-1 and MIP-1β were shown. A significant increase in VEGF-A, HGF, VEGF-D, as well as MCP-1 concentrations was shown in the lacrimal fluid. The inversion of PDGF-BB concentrations in serum and lacrimal fluid was noted. Analysis of intraocular cytokine levels revealed a significant increase in VEGF-A and HGF concentrations, with marked decrease in MIP-1α and MIP-1β. PDGF-BB in 100% of cases was determined only in vitreous body of patients with retinal angiomatosis. With respect to the revealed characteristic shifts of HGF/SF intraocular production in retinal capillary hemangioma, it seems relevant to search ways for its inhibition, thus providing potential basis for a new therapeutic strategy in treatment of retinal angiomatosis