Constructive adaptability of machinery to operate effectively in the full cycle of technological works

2019 ◽  
Vol 2 (2) ◽  
pp. 58-68
Author(s):  
N. S. Sevryugina ◽  
A. S. Apatenko

Introduction: the feasibility of the strategic development of the country in the long term from the point of view of technical support of production areas is considered. Presents an analytical review of designs of technological machines manufacturers, highlighted the work of leading Russian scientists Balovnev V.I., Zorin A.V., Goncharov N.V., Korchagin P.A., Pavlov V.P. and others aimed at solving problems of competitiveness and import substitution of land transport and technological complexes, focused on operation in different sectors of the economy. The increase in the efficiency of technological machines of a wide range of use by constructive refinement by placing in the drive mechanism of the working equipment of the quick-detachable device: quick coupler, which provides the versatility of the base machine, reducing the cost of performing a full cycle of technological works. The modified model of the quick coupler is developed, mathematical, computer modeling and full-scale tests are carried out. Proved the feasibility of the introduction of the indicator variable characterizing the efficiency of the multifunctional machine at the put costs.Methods: the study is based on the analysis of the works of leading domestic and foreign scientists in the field of improving existing technological machines. The theoretical and methodological basis of the study was a systematic approach, probability theory, methods of mathematical analysis, simulation, similarity theory, reliability theory, theory of planning and static processing of results.Results and discussion: a modified model of the quick coupler is developed, a distinctive feature of the design is the model of the unloaded locking mechanism. Simulation modeling, full-scale and bench tests on the level of structural reliability are carried out.Conclusion: operators of technological machines are proposed to supplement the working equipment with a quick coupler with an unloaded locking mechanism that allows to constructively adapt the machines to the effective functioning in the full cycle of technological works by expanding the range of working equipment used and reducing operating costs.

Author(s):  
Brian N. Leis

Abstract The emergence in the early 1970s of what about a decade later became the first release of ASME B31G began the development and evolution of criteria to assess the severity of metal-loss defects. Motivated by the desire to reduce the conservatism embedded in B31G, the late 1980s saw the release of Modified B31G, with that same report also introducing RSTRENG, which quantified “riverbottom” effects. The desire to avoid excessive conservatism in their application to higher-strength Grades gave rise to alternative criteria for such applications. PCORRC appeared in 1997, with early versions of DNV RP-F101 and British Gas’ LPC-1 criteria following shortly thereafter. It has since become evident for isolated smooth-bottomed features that in addition to feature length and depth, its width can be a factor, as can its planar shape, and through-thickness profile. This paper builds on insight gained from the prior work, presenting and validating a Level 1 failure criteria for isolated metal-loss features. The defect-free term for this Level 1 criterion relies on the Zhu-Leis criterion for defect-free pipe failure. That criterion is coupled to a recalibrated defect term analogous to PCORRC, whose extension to include the effects of width is considered. The resulting Level 1 criterion is validated in reference to full-scale tests of pipe with metal-loss, which include a mix of real corrosion and flat-bottomed machined features. These tests consider Grades from Gr B to X100, a wide range of diameters and thicknesses, and in many cases the effect of width. Finite element results are used to illustrate the role of width. Benchmarked against almost 80 full-scale tests it is shown that this new approach affects a reduction in conservatism. At the same time, it provides clear benefits in regard to reduced predictive scatter, as well as a reduction in required maintenance, and the scope of features that must be considered in field-digs.


2020 ◽  
pp. 43-50
Author(s):  
Yauheniya N. Saukova

It is shown that the issues of metrological traceability for extended self-luminous objects with a wide range of brightness have not yet been resolved, since the rank scales of embedded systems are used for processing digital images. For such scales, there is no “fixed” unit, which does not allow you to get reliable results and ensure the unity of measurements. An experiment is described to evaluate the accuracy of determining the intensity (coordinates) of the color of self-luminous objects. In terms of repeatability and intermediate precision compared to the reference measurement method, the color and chromaticity coordinates of self-luminous objects (reference samples) were determined by their multiple digital registration using technical vision systems. The possibilities of the developed methodology for colorimetric studies in hardware and software environments from the point of view of constructing a multidimensional conditional scale are determined.


2020 ◽  
Vol 7 (2) ◽  
pp. 34-41
Author(s):  
VLADIMIR NIKONOV ◽  
◽  
ANTON ZOBOV ◽  

The construction and selection of a suitable bijective function, that is, substitution, is now becoming an important applied task, particularly for building block encryption systems. Many articles have suggested using different approaches to determining the quality of substitution, but most of them are highly computationally complex. The solution of this problem will significantly expand the range of methods for constructing and analyzing scheme in information protection systems. The purpose of research is to find easily measurable characteristics of substitutions, allowing to evaluate their quality, and also measures of the proximity of a particular substitutions to a random one, or its distance from it. For this purpose, several characteristics were proposed in this work: difference and polynomial, and their mathematical expectation was found, as well as variance for the difference characteristic. This allows us to make a conclusion about its quality by comparing the result of calculating the characteristic for a particular substitution with the calculated mathematical expectation. From a computational point of view, the thesises of the article are of exceptional interest due to the simplicity of the algorithm for quantifying the quality of bijective function substitutions. By its nature, the operation of calculating the difference characteristic carries out a simple summation of integer terms in a fixed and small range. Such an operation, both in the modern and in the prospective element base, is embedded in the logic of a wide range of functional elements, especially when implementing computational actions in the optical range, or on other carriers related to the field of nanotechnology.


2019 ◽  
Author(s):  
Inc. OEAPS

"Academy Journal" is an international, peer-reviewed monthly journal. It is devoted to the publication of original scientific research articles dealing with various academic disciplines.Articles that may be of interest to a wide range of researchers are welcome, and not limited to those who work on specific research subjects."Academy Journal" has an open archive, according to which published articles are available immediately after publication, excluding embargoes.Expert reviewThere is one blind verification process in the journal. All articles will be initially evaluated by the editor for compliance with the journal. Manuscripts that are considered appropriate are then usually sent to at least two independent peer reviewers to assess the scientific quality of the article. The editor is responsible for the final decision on whether to accept or reject the article. The editor's decision is final.The main criterion used in assessing the manuscript submitted to the journal is: uniqueness or innovation in the work from the point of view of the methodology being developed and / or its application to a problem of particular importance in the public sector or service sector and / or the setting in which the efforts, for example, in the developing region of the world. That is, the very model / methodology, application and context of problems, at least one of them must be unique and important.Additional criteria considered in the consideration of the submitted document are its accuracy, organization / presentation (ie logical flow) and recording quality.


2018 ◽  
Vol 8 (2) ◽  
pp. 49-73
Author(s):  
Petr Adamec

The core issue of this paper is a quality in the lifelong learning. The aim of the contribution is to describe the area, level and dimensions of quality in a wide range of lifelong learning programs, respectively of further education, which are realized in the sense of § 60 and 60a of the Higher Education Act. The content of the paper also focuses on the theoretical and practical starting points of the quality phenomenon, both from the historical point of view and especially from the perspective of the current focus and concept of university policy in the European and Czech region. The paper also presents the results of a survey focusing on approaches to the quality assurance systems in the concept of components at selected public university.


Antioxidants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1224
Author(s):  
Stefania Marano ◽  
Cristina Minnelli ◽  
Lorenzo Ripani ◽  
Massimo Marcaccio ◽  
Emiliano Laudadio ◽  
...  

Synthetic nitrone spin-traps are being explored as therapeutic agents for the treatment of a wide range of oxidative stress-related pathologies, including but not limited to stroke, cancer, cardiovascular, and neurodegenerative diseases. In this context, increasing efforts are currently being made to the design and synthesis of new nitrone-based compounds with enhanced efficacy. The most researched nitrones are surely the ones related to α-phenyl-tert-butylnitrone (PBN) and 5,5-dimethyl-1-pyrroline N-oxide (DMPO) derivatives, which have shown to possess potent biological activity in many experimental animal models. However, more recently, nitrones with a benzoxazinic structure (3-aryl-2H-benzo[1,4]oxazin-N-oxides) have been demonstrated to have superior antioxidant activity compared to PBN. In this study, two new benzoxazinic nitrones bearing an electron-withdrawing methoxycarbonyl group on the benzo moiety (in para and meta positions respect to the nitronyl function) were synthesized. Their in vitro antioxidant activity was evaluated by two cellular-based assays (inhibition of AAPH-induced human erythrocyte hemolysis and cell death in human retinal pigmented epithelium (ARPE-19) cells) and a chemical approach by means of the α,α-diphenyl-β-picrylhydrazyl (DPPH) scavenging assay, using both electron paramagnetic resonance (EPR) spectroscopy and UV spectrophotometry. A computational approach was also used to investigate their potential primary mechanism of antioxidant action, as well as to rationalize the effect of functionalization on the nitrones reactivity toward DPPH, chosen as model radical in this study. Further insights were also gathered by exploring the nitrone electrochemical properties via cyclic voltammetry and by studying their kinetic behavior by means of EPR spectroscopy. Results showed that the introduction of an electron-withdrawing group in the phenyl moiety in the para position significantly increased the antioxidant capacity of benzoxazinic nitrones both in cell and cell-free systems. From the mechanistic point of view, the calculated results closely matched the experimental findings, strongly suggesting that the H-atom transfer (HAT) is likely to be the primary mechanism in the DPPH quenching.


2021 ◽  
Vol 14 (3) ◽  
pp. 1-26
Author(s):  
Andrea Asperti ◽  
Stefano Dal Bianco

We provide a syllabification algorithm for the Divine Comedy using techniques from probabilistic and constraint programming. We particularly focus on the synalephe , addressed in terms of the "propensity" of a word to take part in a synalephe with adjacent words. We jointly provide an online vocabulary containing, for each word, information about its syllabification, the location of the tonic accent, and the aforementioned synalephe propensity, on the left and right sides. The algorithm is intrinsically nondeterministic, producing different possible syllabifications for each verse, with different likelihoods; metric constraints relative to accents on the 10th, 4th, and 6th syllables are used to further reduce the solution space. The most likely syllabification is hence returned as output. We believe that this work could be a major milestone for a lot of different investigations. From the point of view of digital humanities it opens new perspectives on computer-assisted analysis of digital sources, comprising automated detection of anomalous and problematic cases, metric clustering of verses and their categorization, or more foundational investigations addressing, e.g., the phonetic roles of consonants and vowels. From the point of view of text processing and deep learning, information about syllabification and the location of accents opens a wide range of exciting perspectives, from the possibility of automatic learning syllabification of words and verses to the improvement of generative models, aware of metric issues, and more respectful of the expected musicality.


Author(s):  
Kazem Sadati ◽  
Hamid Zeraatgar ◽  
Aliasghar Moghaddas

Maneuverability of planing craft is a complicated hydrodynamic subject that needs more studies to comprehend its characteristics. Planing craft drivers follow a common practice for maneuver of the craft that is fundamentally different from ship’s standards. In situ full-scale tests are normally necessary to understand the maneuverability characteristics of planing craft. In this paper, a study has been conducted to illustrate maneuverability characteristics of planing craft by full-scale tests. Accelerating and turning maneuver tests are conducted on two cases at different forward speeds and rudder angles. In each test, dynamic trim, trajectory, speed, roll of the craft are recorded. The tests are performed in planing mode, semi-planing mode, and transition between planing mode to semi-planing mode to study the effects of the craft forward speed and consequently running attitude on the maneuverability. Analysis of the data reveals that the Steady Turning Diameter (STD) of the planing craft may be as large as 40 L, while it rarely goes beyond 5 L for ships. Results also show that a turning maneuver starting at planing mode might end in semi-planing mode. This transition can remarkably improve the performance characteristics of the planing craft’s maneuverability. Therefore, an alternative practice is proposed instead of the classic turning maneuver. In this practice, the craft traveling in the planing mode is transitioned to the semi-planing mode by forward speed reduction first, and then the turning maneuver is executed.


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