A huge part of the territory of Russia is located in the permafrost zone. Ensuring the reliability of pipeline systems transporting hydrocarbons in these conditions requires an integrated approach that takes into account the structure of the soil, the peculiarities of construction methods, the temperature characteristics of the soil and the transported products. Evaluation of the interaction of the pipeline with frozen ground is an important factor in the design. And the justification of the choice of an engineering solution for the construction of pipeline systems, ensuring their stable position, is one of the tasks of our research. The gas pipeline at the Kamennomysskoye-Sea field is considered as an object of research. A brief description of the features of the construction area is given. A strength calculation was performed, on the basis of which the design parameters of the pipeline were adopted. A comparative analysis of the ways of laying the pipeline was carried out, which made it possible to identify the most satisfying conditions of reliability and economic efficiency.
Keywords: hydrocarbons, pipeline, permafrost soil, subterranean laying, elevated laying, strength calculation, sustainability calculation
Soft intellectual property cores (IP-cores) based on a field programmable gate array (FPGA) are blocks that do not have a specific placement and prerouted interconnects on the chip. These blocks make it possible to speed up the design process of the digital circuits based on the FPGAs, while the use of the FPGA architecture specialized resources can increase the performance of the developed circuits that include soft IP-cores. These resources should be considered both in the soft IP-cores design and in the development of methods and algorithms for computer-aided design systems to achieve the greatest efficiency. In this paper, two soft IP-cores implementations are developed and a comparative analysis of the obtained blocks’ volumes and the used routing resources is carried out. In the first implementation, both the logical and layout syntheses take into account the basic FPGA structural features and FPGA specialized resources. In the second, only standard library elements and a common routing tree are used. On the results of the analysis, the advantages of the FPGA specialized architecture specialized resources in the soft IP-cores design are shown. Also the paper describes the specifics of these resources introduced by the FPGA developers, and the implementation features of the following soft IP-cores: n-bit adder / subtractor, up counter to n and n-bit shift register.
Keywords: intellectual property core, computer aided design, field programmable gate array, design flow, routing
The article describes the specifics of OOP concepts implementation in the open source projects that contain address book model in comparison to OASIS UBL Party Reference model. The open source software analysis is performed using the formal criteria for evaluating the matching between open source project models and reference model based on quantitative characteristics, conceptual graph transformation and cluster analysis. First, the scope coverage, elaboration factor and structural connectedness were calculated based on model parameters. Second, the domain models were represented as conceptual graphs and they were compared based on semantic equivalence. And third, the model was clustered into four subdomains, and quantitative characteistics were evaluated separately for each cluster. Based on the experimental results of model analysis the authors propose methods to reduce the conceptual mismatch between reference model and project models.
Keywords: OOP, semantic analysis, reference model, OASIS UBL, conceptual graph, cluster analysis
The article presents the usage of the semantic network for storing and retrieving information from unstructured sources. The authors describe the semantic network model based on labeled oriented graph, consider basic semantic network elements (concepts, relations and attributes) and basic relation types between elements (hyponymic and meronimic as well as class-instance relations), and define main single and group operations on the network. Besides the method of storing the concept instances and related wordforms and glosses for automated information retrieval from semi-structured sources is provided. The designed semantic network is decomposed into atomic concepts providing absence of stored information redundancy without necessity to apply the normalization procedure. The developed model was applied in several practical tasks, for example in real estate information parsing, the address information system input validation, and information extraction from spreadsheet data. The model was improved and extended based on experimental results.
Keywords: semantic network, graph model, concept, relation, attribute, instance, semi-structured data