Analysis of structures of flat planting machines

2021 ◽  
Vol 13 (1) ◽  
pp. 140-148
Author(s):  
Andrіі Slabkyі ◽  
◽  
Olexandr Manzhilevskyy ◽  
Olexandr Polishchuk ◽  
◽  
...  

One of the methods of material processing is considered, which allows to obtain high geometric accuracy and low surface roughness of parts, namely their abrasive finishing. The high quality of machining of parts in this way is due to the use of coordinated relative movement of the workpiece and the cutting tool. According to the kinematic features, most lapping machines can be divided into two groups: machines with oscillating working motion and machines with rotating lapping motion. The machines of the first group are more common due to the simplicity of their design and versatility. However, the possibility of their use is limited by the size range of the workpieces and uneven wear of the cutting tool and, as a consequence, the uneven surface treatment of the part. The machines of the second group are considered the most versatile, as they allow processing a wide range of parts, varying in shape and size, but they are also not without such a disadvantage as uneven wear of the cutting tool with all the corresponding consequences. Improving the efficiency of abrasive finishing by complicating the trajectory of the relative movement of the tool and the part, ie the formation of a unique mutual working movement of the lapping and the movement of the workpiece, is one of the most common areas. The main disadvantage of equipment that provides processing of parts on this principle is, in most cases, limited regulation of the operating parameters of the cutting process, so this area remains promising and has broad prospects for development. The constructive scheme of the hydraulic-pulse flat-lapping machine offered in work thanks to a combination of advantages of the hydraulic-pulse drive with use of numerical program control will allow to provide unique mutual multi-movement of preparation and the lapping tool with a possibility of adjustment of its parameters in the course of processing. Purposeful choice of the shape and density of the trajectory of the working movement of the tool will form a micro relief of the treated surface with the necessary statistical parameters and low roughness.

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.


1998 ◽  
Vol 2 ◽  
pp. 115-122
Author(s):  
Donatas Švitra ◽  
Jolanta Janutėnienė

In the practice of processing of metals by cutting it is necessary to overcome the vibration of the cutting tool, the processed detail and units of the machine tool. These vibrations in many cases are an obstacle to increase the productivity and quality of treatment of details on metal-cutting machine tools. Vibration at cutting of metals is a very diverse phenomenon due to both it’s nature and the form of oscillatory motion. The most general classification of vibrations at cutting is a division them into forced vibration and autovibrations. The most difficult to remove and poorly investigated are the autovibrations, i.e. vibrations arising at the absence of external periodic forces. The autovibrations, stipulated by the process of cutting on metalcutting machine are of two types: the low-frequency autovibrations and high-frequency autovibrations. When the low-frequency autovibration there appear, the cutting process ought to be terminated and the cause of the vibrations eliminated. Otherwise, there is a danger of a break of both machine and tool. In the case of high-frequency vibration the machine operates apparently quiently, but the processed surface feature small-sized roughness. The frequency of autovibrations can reach 5000 Hz and more.


2019 ◽  
pp. 462-471
Author(s):  
Lyudmila Shirokova

The historical polyethnicity of the Slovak society and the connected problems of the interrelations of cultures, ethics, interpersonal relations, are reflected in the works of modern Slovak prose. They are represented most clearly in the novels of middle generation writers P. Rankov, S. Lavrík, P. Krištúfek. They dwell upon the dramatical events of the 20 th century. They cover wide range problems, from the fruitful coexistence of various ethnic groups and their representatives to national contradictions and racial repressions. The artistic quality of the mentioned works, their composition, the way of narrating, the type of the main character, can be highly evaluated. For example, in a novel by P. Rankov the plot, in spite of its linearity, is a chain of episodes in the span of 30 years from the life of the main characters. It reflects not only their fates, but also the historical and political changes of the world they live in. The main female character of a S. Lavrík ’s novel narrates about everyday life and tragedies in the lives of the dwellers of a Slovak town in the Slovak Republic during the war. P. Krištúfek in his novel focuses on several decades from the life of a Slovak-Jewish family and dwellers of a Slovak provincial society with types and relations specific for this milieu.


Author(s):  
Katherine V. Whittington

Abstract The electronics supply chain is being increasingly infiltrated by non-authentic, counterfeit electronic parts, whose use poses a great risk to the integrity and quality of critical hardware. There is a wide range of counterfeit parts such as leads and body molds. The failure analyst has many tools that can be used to investigate counterfeit parts. The key is to follow an investigative path that makes sense for each scenario. External visual inspection is called for whenever the source of supply is questionable. Other methods include use of solvents, 3D measurement, X-ray fluorescence, C-mode scanning acoustic microscopy, thermal cycle testing, burn-in technique, and electrical testing. Awareness, vigilance, and effective investigations are the best defense against the threat of counterfeit parts.


2020 ◽  
Vol 1 (10(79)) ◽  
pp. 12-18
Author(s):  
G. Bubyreva

The existing legislation determines the education as "an integral and focused process of teaching and upbringing, which represents a socially important value and shall be implemented so as to meet the interests of the individual, the family, the society and the state". However, even in this part, the meaning of the notion ‘socially significant benefit is not specified and allows for a wide range of interpretation [2]. Yet the more inconcrete is the answer to the question – "who and how should determine the interests of the individual, the family and even the state?" The national doctrine of education in the Russian Federation, which determined the goals of teaching and upbringing, the ways to attain them by means of the state policy regulating the field of education, the target achievements of the development of the educational system for the period up to 2025, approved by the Decree of the Government of the Russian Federation of October 4, 2000 #751, was abrogated by the Decree of the Government of the Russian Federation of March 29, 2014 #245 [7]. The new doctrine has not been developed so far. The RAE Academician A.B. Khutorsky believes that the absence of the national doctrine of education presents a threat to national security and a violation of the right of citizens to quality education. Accordingly, the teacher has to solve the problem of achieving the harmony of interests of the individual, the family, the society and the government on their own, which, however, judging by the officially published results, is the task that exceeds the abilities of the participants of the educational process.  The particular concern about the results of the patriotic upbringing served as a basis for the legislative initiative of the RF President V. V. Putin, who introduced the project of an amendment to the Law of RF "About Education of the Russian Federation" to the State Duma in 2020, regarding the quality of patriotic upbringing [3]. Patriotism, considered by the President of RF V. V. Putin as the only possible idea to unite the nation is "THE FEELING OF LOVE OF THE MOTHERLAND" and the readiness for every sacrifice and heroic deed for the sake of the interests of your Motherland. However, the practicing educators experience shortfalls in efficient methodologies of patriotic upbringing, which should let them bring up citizens, loving their Motherland more than themselves. The article is dedicated to solution to this problem based on the Value-sense paradigm of upbringing educational dynasty of the Kurbatovs [15].


2019 ◽  
Vol 65 (1) ◽  
pp. 16-26
Author(s):  
Pavel Rumyantsev ◽  
Petr Nikiforovich ◽  
Andrey Poloznikov ◽  
Andrey Abrosimov ◽  
Vladimir Saenko ◽  
...  

Mutation BRAFV600E is highly specific for papillary thyroid carcinoma. It’s detected in 40-70% of all papillary thyroid carcinoma cases. Moreover this mutation is noticed in anaplastic carcinoma in 40-50%.This fact gives a chance to select patients and provide targeted therapy with multi-kinase inhibitors in cases of unresectable anaplastic carcinoma. The influence of BRAF V600E mutation for response to radioactive iodine therapy requires more evidence-based research. Existing methods for determining the BRAFV600E mutation have different accuracy, availability and cost. Other methodological aspects are also associated with the sample preparation of biological material, the quality of reagents, and the cross-validation of research results. In this review, on the basis of our own experience and literature data, the indications for determining the mutation of the BRAFV600E gene in clinical practice are refined, and a comprehensive comparative analysis of modern research methods has been conducted. This review is focused on a wide range of specialists of different types: oncologists, endocrinologists, radiologists, pathologists, and biologists.


In his philosophical writings, Coleridge increasingly developed his thinking about imagination, a symbolizing precursor to contemplation, to a theory of contemplation itself, which for him occurs in its purest form as a manifestation of ‘Reason’. Coleridge is a particularly challenging figure because he was a thinker in process, and something of an omnimath, a Renaissance man of the Romantic era. The dynamic quality of his thinking, the ‘dark fluxion’ pursued but ultimately ‘unfixable by thought’, and his extensive range of interests make essential an approach that is philosophical yet also multi-disciplinary. This is the first collection of essays to be written mainly by philosophers and intellectual historians on a wide range of Coleridge’s philosophical writings. With a foreword by Baroness Mary Warnock, and original essays on Coleridge and Contemplation by prominent philosophers such as Sir Roger Scruton, David E. Cooper, Michael McGhee, and Andy Hamilton, this volume provides a stimulating collection of insights and explorations into what Britain’s foremost philosopher-poet had to say about the contemplation that he considered to be the highest of the human mental powers. The essays by philosophers are supported by new developments in philosophically minded criticism from Coleridge scholars in English departments, including Jim Mays, Kathleen Wheeler, and James Engell. They approach Coleridge as an energetic yet contemplative thinker concerned with the intuition of ideas and the processes of cultivation in self and society. Other essays, from intellectual historians and theologians, clarify the historical background, and ‘religious musings’, of Coleridge’s thought regarding contemplation.


This is the sixth volume of Oxford Studies in Agency and Responsibility. The papers were drawn from the fourth biennial New Orleans Workshop in Agency and Responsibility (NOWAR), held November 2–4, 2017. The essays cover a wide range of topics relevant to agency and responsibility: the threat of neuroscience to free will; the relevance of resentment and guilt to responsibility; how control and self-control pertain to moral agency, oppression, and poverty; responsibility for joint agency; the role and conditions of shame in theories of attributability; how one might take responsibility without blameworthy quality of will; what it means to have standing to blame others; the relevance of moral testimony to moral responsibility; how to build a theory of attributabiity that captures all the relevant cases; and how thinking about blame better enables us to dissolve a dispute in moral philosophy between actualists and possibilists.


2021 ◽  
Vol 413 (9) ◽  
pp. 2389-2406 ◽  
Author(s):  
Soumyabrata Banik ◽  
Sindhoora Kaniyala Melanthota ◽  
Arbaaz ◽  
Joel Markus Vaz ◽  
Vishak Madhwaraj Kadambalithaya ◽  
...  

AbstractSmartphone-based imaging devices (SIDs) have shown to be versatile and have a wide range of biomedical applications. With the increasing demand for high-quality medical services, technological interventions such as portable devices that can be used in remote and resource-less conditions and have an impact on quantity and quality of care. Additionally, smartphone-based devices have shown their application in the field of teleimaging, food technology, education, etc. Depending on the application and imaging capability required, the optical arrangement of the SID varies which enables them to be used in multiple setups like bright-field, fluorescence, dark-field, and multiple arrays with certain changes in their optics and illumination. This comprehensive review discusses the numerous applications and development of SIDs towards histopathological examination, detection of bacteria and viruses, food technology, and routine diagnosis. Smartphone-based devices are complemented with deep learning methods to further increase the efficiency of the devices.


Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1499
Author(s):  
Ján Jobbágy ◽  
Peter Dančanin ◽  
Koloman Krištof ◽  
Juraj Maga ◽  
Vlastimil Slaný

Recently, the development of agricultural technology has been focused on achieving higher reliability and quality of work. The aim of the presented paper was to examine the possibilities of evaluating the quality of work of wide-area irrigation machinery by monitoring the coefficients of uniformity and non-uniformity of irrigation. The object of the research was pivot irrigation machinery equipped with sprinklers with a total length from 230 to 540 m. The commonly applied quality of work parameter for wide-range irrigators is the irrigation uniformity coefficient according to Heermann and Hein CUH. Work quality evaluations were also carried out through other parameters applicable in practice, such as irrigation uniformity coefficients calculated according to Christiansen CU, Wilcox and Swailes Cws, and our introduced parameters, the coefficient ar (derived from the degree of unevenness according to Oehler) and the degree of uniformity γr (derived from the degree of non-uniformity according to Voight). Other applied parameters for determining the quality of work of wide-range irrigation machinery were the coefficients of irrigation uniformity according to Hart and Reynolds CUhr, further according to Criddle CUcr and subsequently according to Beale and Howell CUbr. Next, the parameters of the non-uniformity coefficient according to Oehler a, the coefficient of variation according to Stefanelli Cv, the degree of non-uniformity according to Voigt γ and the degree of non-uniformity according to Hofmeister Ef were evaluated. Field tests were performed during the growing season of cultivated crops (potatoes, corn and sugar beet) in the village of Trakovice (agricultural enterprise SLOV-MART, southwest of the Slovakia) and in the district of Piešťany (Agrobiop, joint stock company). During the research, the inlet operating parameters (speed stage, inlet pressure, irrigation dose), technical parameters (number of sprayers, total length, number of chassis) and weather conditions (wind speed and temperature) were recorded. The obtained results were examined by one-way ANOVA analysis depending on the observed coefficient or input conditions and subsequently verified by Tukey and Duncan tests as needed. Irrigation uniformity values ranged from 67.58% (Cws) to 95.88% (CUbh) depending on the input conditions. Irrigation non-uniformity values ranged from 8.58 (a, Ef) to 32.42% (Cv). The results indicate a statistically significant effect of the site of interest and thus the impact of particular field conditions (p < 0.05). When evaluating the application of different coefficients of irrigation uniformity, the results showed a statistically significant effect only in the first test (p = 0.03, p < 0.05). During further repeated measurements, the quality of work increased due to the performed inspection of all sprayers and the reduction in the influence of the wind.


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