scholarly journals Improving the Methods for Estimating Radiation Swelling and Progressive Dimensional Changes of the Elements of VVER-1000 Internals

2019 ◽  
pp. 35-42
Author(s):  
O. Makhnenko ◽  
S. Kandala ◽  
M. Cherkashin
Keyword(s):  
Input Data ◽  
Technical Condition ◽  
Point Of View ◽  
Swelling Kinetics ◽  
Current Standard ◽  
Computer Prediction ◽  
Term Operation ◽  
Dimensional Changes ◽  
Standard Program ◽  
Radiation Swelling

The problem in the computer prediction of radiation swelling in the elements of reactor internals when justifying VVER-1000 safe operation is quite relevant. In this regard, the approaches of the current Standard Program (PM-T.0.03.333-15) for assessing the technical condition and lifetime extension of VVER-1000 internals were considered. The paper presents various models of radiation swelling for 08Х18Н10Т steel of which elements of internals are made. A comparative analysis of the prediction results for various models has been performed. It is shown that the approaches of the current Standard Program, which take into account factors such as the stress-strain state and radiation creep of the material, are the most relevant. The influence of various fuel campaigns and their sequence on the nature of distribution and the maximum value of radiation swelling, as well as on the stress state in the baffle after long-term operation has been investigated. It is determined that the calculated stationary temperature distribution in the baffle may differ significantly depending on the input data on heat release and accumulated fluence, therefore, it must be calculated for each fuel campaign, and the calculation of the input data averaged for all fuel campaigns may lead to significant errors in the results. From the point of view of the reliability, it is also important to take into account the sequence of fuel campaigns, since, depending on the radiation swelling kinetics, the resulting baffle form can significantly change. The consequences of a possible decrease in cooling efficiency on the external surface of the baffle in the case of reducing the gap between the inner cavity and the baffle are considered, which may cause a local temperature increase in the baffle, but does not lead to a noticeable change in the radiation swelling. However, the radial displacement of the baffle due to thermal expansion increases significantly, which can cause an increase in stresses in the contact area, both in the wall of the cavity and in the baffle. According to the results of the computer analysis, recommendations were formulated to improve the approaches to estimating radiation swelling and progressive dimensional changes in the elements of VVER-1000 internals.

Quantitative Analysis of Microstructure and Modeling of Sintering

2009 ◽  
Vol 624 ◽  
pp. 1-18 ◽  
Author(s):  
Jean Marc Chaix
Keyword(s):  
Image Analysis ◽  
Input Data ◽  
3D Imaging ◽  
Point Of View ◽  
Size Distributions ◽  
Practical Point ◽  
The Past ◽  
Modeling Techniques ◽  
Mean Size ◽  
Sintering Mechanisms

Microstructure is the key scale to understand and describe sintering mechanisms and their consequences at the macroscopic level. As modeling techniques are continuously developing, the need for input data and comparison with more and more accurate descriptions of the evolution is expected to create a growing demand for quantitative microstructure data. Image analysis is the classic way to get these data. This paper reviews the practical use and progresses of this old technique in the sintering literature during the past and recent years. The place of basic tools and more recent ones, such as 3D imaging, are discussed from a practical point of view accounting from sintering models needs: mean size and size distributions in pores and grains, homogeneity, sintering trajectories…

scholarly journals Focal transformation, an imaging concept for signal restoration and noise removal

Geophysics ◽  
2006 ◽  
Vol 71 (6) ◽  
pp. A55-A59 ◽  
Author(s):  
A. J. Berkhout ◽  
D. J. Verschuur
Keyword(s):  
Input Data ◽  
Noise Removal ◽  
Point Of View ◽  
Data Interpolation ◽  
Signal Restoration ◽  
Physical Point ◽  
Seismic Processing ◽  
Promising Tool ◽  
Focal Area ◽  
Forward Operator

Interpolation of data beyond aliasing limits and removal of noise that occurs within the seismic bandwidth are still important problems in seismic processing. The focal transform is introduced as a promising tool in data interpolation and noise removal, allowing the incorporation of macroinformation about the involved wavefields. From a physical point of view, the principal action of the forward focal operator is removing the spatial phase of the signal content from the input data, and the inverse focal operator restores what the forward operator has removed. The strength of the method is that in the transformed domain, the focused signals at the focal area can be separated from the dispersed noise away from the focal area. Applications of particular interest in preprocessing are interpolation of missing offsets and reconstruction of signal beyond aliasing. The latter can be seen as the removal of aliasing noise.

Application of fiber-optic measuring technology and phase-chronometric method for control and monitoring of technical condition of aircraft structures

2021 ◽  
pp. 49-56
Author(s):  
Stanislav S. Khabarov ◽  
Alexander S. Komshin
Keyword(s):  
Fatigue Life ◽  
Fiber Optic ◽  
Technical Condition ◽  
Point Of View ◽  
Flight Performance ◽  
Diagnostic Systems ◽  
Safe Operation ◽  
Excess Reserves ◽  
The Creation ◽  
Original Approach

Problems of ensuring the safe operation of an aircraft from the point of view of the fatigue life of its structure are considered. The relevance of the creation and implementation of diagnostic systems for monitoring the technical condition of structures of complex technical objects is shown on the example of a helicopter. An original approach to the creation and implementation of complex systems for diagnostics and monitoring of the technical condition of complex technical objects is presented, combining fiber-optic measuring technology and phase-chronometric method. It is shown that the use of monitoring and diagnostic systems ensures the transition to operation based on the actual technical condition. The proposed approach makes it possible to increase the time between overhaul intervals and reduce excess reserves in terms of the reliability factors of structures, which increases the flight performance of aircraft.

Сase-systems for development of multiagent system (MAS) in the system of diagnostics and maintenance of vehicles

2021 ◽  
Vol 13 (1) ◽  
pp. 87-93
Author(s):  
Viacheslav Pavlenko ◽  
◽  
Volodymyr Manuylov ◽  
Volodymyr Kuzhel ◽  
◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Technical Condition ◽  
Point Of View ◽  
Multi Agent Systems ◽  
Agent Systems ◽  
Software Products ◽  
Multi Agent ◽  
Software Code ◽  
Low Performance ◽  
Intelligent Methods

The article provides a comparative analysis of existing software products and libraries that allow the design of multi-agent systems for diagnostics and maintenance systems for modern cars. The authors substantiate two main shortcomings inherent in all products - analogues: the need for high qualification of the user as a software code developer, and low performance of intelligent methods in the structure of agents, which worsens their performance. Both manufacturers and car owners are objectively interested in the widespread use of telematics systems for monitoring the technical condition of cars. Predictive diagnostics gives them access to a huge amount of information about all the nuances of car operation, wherever they are, during the entire service life. The application of this approach using a multi-agent system (MAS) will allow taking the next step in this direction. Information from the connected vehicles goes to the main server. Systematization and analysis of data make it possible to establish the causes of malfunctions, identify patterns of their occurrence and make further predictions. Purpose of the work: to perform a comparative analysis of existing software products and libraries that allow the design of multi-agent systems. The topic of the work is disclosed on the example of the analysis of software tools for the development and design of MAS at the present stage. There are a number of systems and libraries on the market designed for the development of multi-agent systems. These Case - systems are suitable for the development of multi-agent systems of any direction, that is, they are universal from this point of view. Therefore, for us it is a universal application tool for the automotive industry. Ultimately, the work performed a comparative analysis of existing software products and libraries that allow the design of multi-agent systems. The analysis revealed two main drawbacks inherent in all products - analogs: the need for high user qualifications as a developer of software code, and low indicators of the possibilities of introducing intelligent methods into the structure of agents, worsens the indicators of their work.

scholarly journals Alterações dimensionais em pastas de óxido de zinco/eugenol: um novo método para sua mensuração

2021 ◽  
pp. 39-55
Author(s):  
Léo Werner Süffert ◽  
Ennio Pessôa
Keyword(s):  
Standard Deviation ◽  
Personal Information ◽  
High Variability ◽  
Point Of View ◽  
New Method ◽  
Extensive Review ◽  
Review Of The Literature ◽  
Dimensional Changes ◽  
Impression Materials ◽  
Clinical Point

After an extensive review of the literature, regarding zinc.oxide/eugenol impression pastes, we selected 20 of the most representatives as our references. Trough personal information of several of the investigators it was discovered that dimensional changes of theese materials is one of the most difficult properties to be measured. A new method was developed to measure dimensional changes ot 4 (four) of the most widely used zinc.oxide/eugenol impression materials in Brazil. The results, presented through several graphs and tables showed that dimensional changes varied from 0,003%, values which may probably be considered negligible from a clinical point of view. We noticed, however, high values for standard deviation and variance which indicate the high variability within the experiments. Those values were not found when we used the same method with mercaptan and silicone impression materials, in which the measurement of dimensional changes was highly reproducible. One hypothesis (which we intend to investigate in a later research) is that, during storage, a sedimentation could occur, of the components of greater density! Consequently ther might result a change in composition, independent of the method used to establishe the proportion of the two pastes, be it by wheight or measurement of lenght, which could be the cause of variability of the composition of each mixture!

scholarly journals FIELD OF TASKS OF THE CONSTRUCTION OBJECT

2020 ◽  
pp. 78-83
Author(s):  
Elena Gorda
Keyword(s):  
Life Cycle ◽  
Information Technologies ◽  
Technical Condition ◽  
Point Of View ◽  
Information Modeling ◽  
Theoretical Point ◽  
Construction Design ◽  
Information Models ◽  
Merger Integration ◽  
Concept Classification

The generalization of the concept of the task in terms of information environments of construction [ISB] is performed. The approach to the presentation of such concepts as construction issues, construction problem, ontology, idea, concept, classification of problems, tasks, directions, objects included in the staging part of the tasks taking into account the specifics of the tasks solved within the developed information technologies in construction issues. The paper defines and investigates on the basis of methods of construction geodesy the actual tasks of construction, design, modeling, monitoring and their totality in the field of construction by means of information theory. An approach to the description of the technical condition of a construction object on the basis of information modeling in the management of the construction process and information modeling within the life cycle is proposed and described. Information modeling is a process, the results of each stage of which, ie information models of the building, differ greatly from each other depending on the stage of the life cycle of the object and the requirements for modeling in solving emerging problems. The construction object strongly depends on the stage of its existence: if during the design it is virtual, and during construction it gradually finds a real embodiment, then at a long stage of operation the building enters a period of stability and is no longer subject to significant changes. An information model is a variable object that depends on the range of tasks to be solved. Using the methods of construction geodesy in the field of construction, the field of problems, class of problems, the concept of the problem, the state of the problem, subtasks, chains of problems, problem solving and the result of solving the problem, the relationship between problems setting the transformation of aggregation, merger, integration. The urgency of the task from a theoretical point of view is determined by the expansion of the ontology of construction as a science, from an applied point of view is determined by the possibility of accurate formalization of regulatory information and documentation in construction.

scholarly journals Acetaminophen Metabolism Revisited Using Non-Targeted Analyses: Implications for Human Biomonitoring

2020 ◽  
Author(s):  
Arthur David ◽  
Jade Chaker ◽  
Thibaut Léger ◽  
Raghad Al-Salhi ◽  
Marlene Danner Dalgaard ◽  
...  
Keyword(s):  
Phase Ii ◽  
Enterohepatic Circulation ◽  
High Resolution Mass Spectrometry ◽  
Parent Compound ◽  
Human Biomonitoring ◽  
Relevant Information ◽  
Point Of View ◽  
Internal Exposure ◽  
Current Standard ◽  
Excretion Rates

The analgesic paracetamol (N-acetyl-4-aminophenol, APAP) is commonly used to relieve pain, fever and malaise. While sales have increased worldwide, a growing body of experimental and epidemiological evidence has suggested APAP as a possible risk factor for various health disorders. To perform internal exposure-based risk assessment, the use of accurate and optimized biomonitoring methods is criticical. However, retrospectively assessing pharmaceutical use of APAP in humans is challenging because of its short half-life. The objective of this study was to address the key biomonitoring issues with APAP using current standard analytical methods based on urinary analyses of free APAP and its phase II conjugates. Using non-targeted analyses based on high-resolution mass spectrometry, we identified in a controlled longitudinal exposure study with male volunteers, unrecognized APAP metabolites with delayed formation and excretion rates. We postulate that these metabolites are formed via the thiomethyl shunt after the enterohepatic circulation as already observed in rodents. Importantly, the conjugated thiomethyl metabolites were (i) of comparable diagnostic sensitivity as the free APAP and its phase II conjugates detected by current methods; (ii) had delayed peak levels in blood and urine compared to other APAP metabolites and therefore potentially extend the window of exposure assessment; and (iii) provide relevant information regarding metabolic pathways of interest from a toxicological point of view. Including these metabolites in future APAP biomonitoring methods provide an option to decrease potential underestimation of APAP use and challenges the notion that the standard methods in biomonitoring based exclusively on the parent compound and its phase II metabolites are adequate for human biomonitoring of non-persistant chemical such as APAP. <br>

OPERATIONAL ASSESSMENT OF THE LIMIT STATE OF TRACTOR UNITS WITH THE USE OF INDICATOR COUNTERS

2021 ◽  
Vol 3 (144) ◽  
pp. 12-21
Author(s):  
Nikolay A. Petrishchev ◽  
◽  
Mikhail N. Kostomakhin ◽  
Aleksandr S. Sayapin ◽  
Igor’ M. Makarkin ◽  
...  
Keyword(s):  
Limit State ◽  
Technical Condition ◽  
Point Of View ◽  
Research Purpose ◽  
Diagnostic Tools ◽  
Diagnostic Process ◽  
Technical Documentation ◽  
Limit States ◽  
Limit Condition ◽  
Reliability Indicators

In accordance with GOST 20793-2009, the tractor and its components are subjected to resource diagnostics before maintenance. The technical condition of the components of the tractor or machine should be checked with the use of control and diagnostic equipment. Currently, the criteria for the limit state are significantly outdated and require revision from the point of view of tightening modern requirements for operational and economic characteristics and reliability indicators. (Research purpose) The research purpose is in analyzing the state of the issue and the current regulatory documentation and making proposals for remote monitoring of the criteria for the limit states of individual components and aggregates. (Materials and methods) The article presents an analysis of scientific and technical documentation, State standards of the Russian Federation and scientific papers on the problems of minimizing technological risks, diagnostics and control suitability for determining the maximum technical condition, and staged studies on the possibility of monitoring the operation of individual components and units online. The article notes the need to adjust the criteria for the maximum technical condition in accordance with the new designs of resource-determining units, aggregates and existing technical regulations. (Results and discussion). The article presents the justification of the diagnostic process and identified contradictions in the design of tractors and existing scientific and technical documentation and standards, and proposed option of using meters-identifiers when upgrading tractors as a system of built-in online diagnostic tools. (Conclusions) Timely, automated monitoring of the technical condition of tractors, which is based on comparing data with the criteria of the limit condition, serves as a justification for the effective operation of equipment with built-in devices for diagnostics, which allows minimizing agrotechnological risks.

scholarly journals RASberry - Robotic and Autonomous Systems for Berry Production

2018 ◽  
Vol 140 (06) ◽  
pp. S14-S18
Author(s):  
Pål Johan From ◽  
Lars Grimstad ◽  
Marc Hanheide ◽  
Simon Pearson ◽  
Grzegorz Cielniak
Keyword(s):  
Control Point ◽  
Autonomous Systems ◽  
Fruit Production ◽  
Point Of View ◽  
Production Costs ◽  
Term Operation ◽  
Manual Labour ◽  
Soft Fruit ◽  
Human Robot Collaboration

The soft fruit industry is facing unprecedented challenges due to its reliance of manual labour. We are presenting a newly launched robotics initiative which will help to address the issues faced by the industry and enable automation of the main processes involved in soft fruit production. The RASberry project (Robotics and Autonomous Systems for Berry Production) aims to develop autonomous fleets of robots for horticultural industry. To achieve this goal, the project will bridge several current technological gaps including the development of a mobile platform suitable for the strawberry fields, software components for fleet management, in-field navigation and mapping, long-term operation, and safe human-robot collaboration. In this paper, we provide a general overview of the project, describe the main system components, highlight interesting challenges from a control point of view and then present three specific applications of the robotic fleets in soft fruit production. The applications demonstrate how robotic fleets can benefit the soft fruit industry by significantly decreasing production costs, addressing labour shortages and being the first step towards fully autonomous robotic systems for agriculture.

PROVISION OF TECHNICAL AND ECOLOGICAL SAFETY OF RIVER JETTY

2013 ◽  
Vol 3 (3) ◽  
pp. 113-118
Author(s):  
M. V YaKOVLEVA ◽  
E. A FROLOV ◽  
V. I ISAEV ◽  
A. E FROLOV
Keyword(s):  
Technical Condition ◽  
Environmental Security ◽  
Health Facilities ◽  
Ecological Safety ◽  
Term Operation ◽  
Significant Damage ◽  
Analysis Of Results

River mooring facilities under their long-term operation have significant damage, which violated their technical and ecological safety of the environment. There are given the results of visual and instrumental inspection of a technical condition of elements of the berth and anchor devices, there is analysis of results, proposed measures for the rehabilitation of health facilities and provision of environmental security.

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