scholarly journals Substantiation of constructive parameters of a frame structure elements of the rope mechanism transport system for storing piece loadings into small warehouses

Author(s):  
Roman Hevko ◽  
Yurii Nykerui ◽  
Taras Dovbush ◽  
Vasyl Oleksyuk

The article provides a theoretical substantiation of the structural parameters of the frame structure for the placement of piece loads, as well as clamping levers with rollers and their arrangement, which interact with the inner surface of the guide ropes of the developed transport system. The established limits of rational parameters and angular positions of levers and their compression springs to the inclined sidewalls for the right and left sides of the movable elements of the frame structure relative to the central vertical axis, as well as the angle of the guide ropes to the horizon. On the basis of the results of calculations and recommendations for the choice of parameters of the proposed technical solutions, a rope mechanism for storing piece loadings into small warehouses was manufactured and preliminary experimental studies were carried out.

2020 ◽  
Vol 8 (1) ◽  
pp. 128-134
Author(s):  
Viktoriya Lerner ◽  
Galina Deryabina ◽  
Aleksey Filatkin ◽  
Yana Platonova

The aim. The karate competition requires the athlete to have a comprehensive manifestation of motor abilities. At the same time, the motor-related area is closely connected with function of the auditory analyzer. Consequently, auditory deprivation affects all types of motor abilities, but, first of all, it affects coordination abilities, since they are implemented on a defective basis of the sensory systems involved in controlling movements. Technical means (punches and kicks, blocks) and tactical means (instant assessment of the situation and making the right decisions) of traditional karate effectively affect the correction of various manifestations of motor coordination. Moreover, the above mentioned karate means affect motor coordination through motor experience in the form of complicating previously mastered movements and mastering new movements with increased coordination difficulties. Methods and organization of the study. We used the following set of complementary theoretical methods to meet the challenge of theoretical substantiation of the research: analysis of psychological, pedagogical and methodical literature, scientific articles on adaptive physical culture, abstracting, generalization and concretization. Results. The research revealed the most common deviations in the manifestation of various components of coordination abilities of children with auditory deprivation. We specified sensitive periods of development of this type of motor qualities in children with hearing impairments. We identified basic karate techniques and actions, which favorably influence the course of development of coordination abilities. Conclusion. Correction and development of the coordination abilities of children with hearing impairments represent the primary task of adaptive physical education. The most favorable age is primary school age. Techniques and actions of traditional karate have a high potential of effective impact on all types of coordination abilities of children.


2020 ◽  
Vol 67 (1) ◽  
pp. 28-34
Author(s):  
Aleksandr V. Vinogradov ◽  
Aleksey V. Bukreev

When repairing and replacing electrical wiring in enterprises, the main difficulty is the lack or poor quality of documentation, plans for conductors laying. Distinguishing wires (cables) and their cores by the color of the shells or using tags attached to the ends is difficult if the shells have the same color and there are no tags. Devices and technical solutions used to identify wires and cables do not allow recognizing conductors without breaking the electrical circuit, removing insulation, and de-energizing the network. Searching for the right conductor is a time-consuming operation. (Research purpose) The research purpose is developing a new microcontroller device for identifying wires using an acoustic signal. (Materials and methods) Literature sources has been searched for devices for conductors identifying. (Results and discussion) The article proposes a method that involves feeding an acoustic signal to a wire at one point and capturing it at another, in order to recognize the desired wire. The article presents results of comparison of the developed microcontroller device for identifying conductors using an acoustic signal with known devices and methods for conductors recognizing. (Conclusions) The article reveals the shortcomings of existing methods and means of identifying wires and cables. Authors performed a theoretical calculation of the sound pressure in the conductor at a given distance. The article presents the calculation of speed of acoustic waves in conductors with different types of insulation. Authors designed a microcontroller device for identifying conductors using an acoustic signal and tested it. It was determined that the device increases the safety of work, reduces the cost of operating internal wiring and identification time; eliminates the violation of wire insulation, the need to disable electrical receivers. The convergence of theoretical calculations and experimental data was shown.


2021 ◽  
Vol 11 (8) ◽  
pp. 3444
Author(s):  
Sergey A. Lavrenko ◽  
Dmitriy I. Shishlyannikov

The authors focus on the process of potash ore production by a mechanized method. They show that currently there are no approved procedures for assessing the performance of heading-and-winning machines operating in the conditions of potash mines. This causes difficulties in determining the field of application of heading-and-winning machines, complicates the search for implicit technical solutions for the modernisation of existing models of mining units, prohibits real-time monitoring of the stability of stope-based technological processes and makes it difficult to assess the performance of the services concerning mining enterprises. The work represents an aggregate assessment of the performance of heading-and-winning machines for potash mines by determining complex indicators describing the technological and technical levels of organising the work in stopes. Such indicators are the coefficients of productivity and energy efficiency, respectively. Experimental studies have been carried out in the conditions of the potash mine of the Verkhnekamskoye potassium-magnesium salt deposit to assess the performance of the latest and most productive Ural-20R heading-and-winning machines manufactured in Russia. Using the above methodological approaches, this paper shows that the unsatisfactory technological performance of the studied machine is due to the low productivity of the mine district transport. The average productivity coefficient was 0.29. At the same time, high values of the energy efficiency coefficient show that the productivity of the machine is on par with design conditions.


2020 ◽  
pp. 40-47
Author(s):  
Андрей Аркадьевич Якимов ◽  
Евгения Германовна Дмитриева

Цель - выявить варианты строения и внутриорганной топографии устьев венечных артерий у взрослого человека при разных типах кровоснабжения желудочкового комплекса сердца. Материал и методы. На вскрытых через некоронарные синусы аорты 65 препаратах клапанов аорты взрослых людей изучили положение устьев венечных артерий, штангенциркулем измеряли минимальный и максимальный диаметры каждого устья, определяли их форму по соотношению диаметров. Результаты. Для устьев обеих артерий типичной была округлая, реже овальная форма. В большинстве случаев левая венечная артерия начиналась в центральной трети, правая - в центральной или задней трети «своего» синуса на уровне верхнего края полулунной заслонки или между ним и синотубулярным соединением. Локализация устьев в пределах синусов, на уровне синотубулярного соединения или выше него была редкой для обеих артерий. В 20 % случаев в правом синусе аорты спереди от устья правой венечной артерии имелось устье конусной артерии. Выводы. Типичные и редкие варианты формы правого и левого устьев, варианты их положения по вертикальной оси аорты одинаковы, варианты их положения по горизонтали различны. Зависимость вариантов формы и положения устьев от типа кровоснабжения желудочков сердца не выявлена. Objective - to reveal common and rare variants of the anatomy and intraorganic topography of the coronary orifices in normal hearts of adult human with regard to patterns of cardiac ventricular blood supply. Material and methods. On 65 specimens of aortic valves opened through non-coronary sinus, the minimal and maximal diameters of each orifice were measured with a caliper, the shape of the orifices was determined according to the ratio of the diameters, and the position of the orifices was studied. Results. The orifices of both right and left coronary arteries were mostly found to be round, less frequently oval. In most cases, the left coronary artery arose from the central third and the right artery arose from the central or posterior third of corresponding sinus at the level of the upper edge of the semilunar cusp or between the edge and the sinotubular junction. The localization of the arterial orifice within the sinuses at the level of sinotubular junction or above it was uncommon for the both arteries. In 20 % of cases, the conal artery arose with its own orifice in front of the mouth of the right coronary artery. Conclusions. Typical and rare shapes of the coronary orifices, variants of their position regarding to vertical axis of the aorta are the same, whereas variants of their position in horizontal axis are different. There is no relationship between variants of form of the orifices, position of the orifices and types of blood supply of heart ventricles.


2021 ◽  
Vol 1037 ◽  
pp. 227-232
Author(s):  
Nikita A. Zemlyanushnov ◽  
Nadezhda Y. Zemlyanushnova

The disadvantage of the known methods of hardening springs is the impossibility of their use when hardening springs of a conical shape or of a shape of a paraboloid of rotation, since they are intended only for cylindrical shape springs and are not suitable for conical shape springs or those of a shape of a paraboloid of rotation specifically because of the difference in the shape of the springs. One of the disadvantages of the known springs hardening mechanisms is the impossibility of hardening the inner surface of the conical compression springs. A new method of hardening springs is proposed, the unmatched advantage of which is the ability to create plastic deformations on the inner and outer surfaces of the spring coils compressed to contact and on the surfaces along the line of contact between the coils. A new advantageous mechanism for hardening springs is proposed, which makes it possible to harden the inner surface of compression springs having a conical shape or a paraboloid shape of rotation, in a compressed state.


2021 ◽  
Author(s):  
Yamini Aiyar ◽  
Vincy Davis ◽  
Gokulnath Govindan ◽  
Taanya Kapoor

The study was not designed to undertake an evaluation of the success or failure of reform. Nor was it specifically about the desirability or defects of the policy reform choices. It took these reform choices and the policy context as a given. It is important to note that the Delhi reforms had its share of criticisms (Kumar, 2016; Rampal, 2016). However, our goal was not to comment on whether these were the “right” reforms or have their appropriateness measured in terms of their technical capability. This study sought to understand the pathways through which policy formulations, designed and promoted by committed leaders (the sound and functional head of the flailing state), transmit their ideas and how these are understood, resisted, and adopted on the ground. In essence, this is a study that sought to illuminate the multifaceted challenges of introducing change and transition in low-capacity settings. Its focus was on documenting the process of implementing reforms and the dynamics of resistance, distortion, and acceptance of reform efforts on the ground. The provocative claim that this report makes is that the success and failure, and eventual institutionalisation, of reforms depend fundamentally on how the frontline of the system understands, interprets, and adapts to reform efforts. This, we shall argue, holds the key to upending the status quo of “pilot” burial grounds that characterise many education reform efforts in India. Reforms are never implemented in a vacuum. They inevitably intersect with the belief systems, cultures, values, and norms that shape the education ecosystem. The dynamics of this interaction, the frictions it creates, and reformers’ ability to negotiate these frictions are what ultimately shape outcomes. In the ultimate analysis, we argue that reforming deeply entrenched education systems (and, more broadly, public service delivery systems) is not merely a matter of political will and technical solutions (although both are critical). It is about identifying the points of reform friction in the ecosystem and experimenting with different ways of negotiating these. The narrative presented here does not have any clear answers for what needs to be done right. Instead, it seeks to make visible the intricacies and potential levers of change that tend to be ignored in the rush to “evaluate” reforms and declare success and failure. Moving beyond success to understand the dynamics of change and resistance is the primary contribution of this study.


Author(s):  
Ruben Brondeel ◽  
Yan Kestens ◽  
Javad Rahimipour Anaraki ◽  
Kevin Stanley ◽  
Benoit Thierry ◽  
...  

Background: Closed-source software for processing and analyzing accelerometer data provides little to no information about the algorithms used to transform acceleration data into physical activity indicators. Recently, an algorithm was developed in MATLAB that replicates the frequently used proprietary ActiLife activity counts. The aim of this software profile was (a) to translate the MATLAB algorithm into R and Python and (b) to test the accuracy of the algorithm on free-living data. Methods: As part of the INTErventions, Research, and Action in Cities Team, data were collected from 86 participants in Victoria (Canada). The participants were asked to wear an integrated global positioning system and accelerometer sensor (SenseDoc) for 10 days on the right hip. Raw accelerometer data were processed in ActiLife, MATLAB, R, and Python and compared using Pearson correlation, interclass correlation, and visual inspection. Results: Data were collected for a combined 749 valid days (>10 hr wear time). MATLAB, Python, and R counts per minute on the vertical axis had Pearson correlations with the ActiLife counts per minute of .998, .998, and .999, respectively. All three algorithms overestimated ActiLife counts per minute, some by up to 2.8%. Conclusions: A MATLAB algorithm for deriving ActiLife counts was implemented in R and Python. The different implementations provide similar results to ActiLife counts produced in the closed source software and can, for all practical purposes, be used interchangeably. This opens up possibilities to comparing studies using similar accelerometers from different suppliers, and to using free, open-source software.


2018 ◽  
Vol 10 (8) ◽  
pp. 168781401879559 ◽  
Author(s):  
Min Xiang ◽  
Feng Xiong ◽  
Yuanfeng Shi ◽  
Kaoshan Dai ◽  
Zhibin Ding

Engineering structures usually exhibit time-varying behavior when subjected to strong excitation or due to material deterioration. This behavior is one of the key properties affecting the structural performance. Hence, reasonable description and timely tracking of time-varying characteristics of engineering structures are necessary for their safety assessment and life-cycle management. Due to its powerful ability of approximating functions in the time–frequency domain, wavelet multi-resolution approximation has been widely applied in the field of parameter estimation. Considering that the damage levels of beams and columns are usually different, identification of time-varying structural parameters of frame structure under seismic excitation using wavelet multi-resolution approximation is studied in this article. A time-varying dynamical model including both the translational and rotational degrees of freedom is established so as to estimate the stiffness coefficients of beams and columns separately. By decomposing each time-varying structural parameter using one wavelet multi-resolution approximation, the time-varying parametric identification problem is transformed into a time-invariant non-parametric one. In solving the high number of regressors in the non-parametric regression program, the modified orthogonal forward regression algorithm is proposed for significant term selection and parameter estimation. This work is demonstrated through numerical examples which consider both gradual variation and abrupt changes in the structural parameters.


2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
P E Erbes ◽  
S G Shulkina ◽  
E N Byvaltseva ◽  
A A Antipova ◽  
E N Smirnova ◽  
...  

Abstract Introduction Obesity is a potent risk factor for the development of kidney disease (CKD). The localization of adipose tissue and its hormonal activity plays an important role in the formation of the cardiorenal relationship. Purpose of work To assess the relationship between visceral fat stores with hormonal activity of adipose tissue, metabolic parameters and markers of renal dysfunction in patients with borderline arterial hypertension (AH) and obesity. Materials and methods The study included 100 people aged 44.8±6.4 years. Group 1 – patients with borderline hypertension – SBP 134.1±4.7 mm Hg; DBP – 84.3±5.9 mm Hg, BMI 36.1±3.2kg/m2. Group 2 was patients with BMI 35.5±3.9 kg/m2, SBP level 120.6±10.1 mm Hg and DBP 70.1±8.4 mm Hg. Albumin/creatinine ratio urine (ACRU), β2 microglobulin, tumor necrosis factor (TNF), interleukin 6 (IL6), monocytechemoattractant protein (MCP-1) was determined in a single portion of morning urine, the level of leptin, resistin and cystatin C was determined by ELISA. Glomerular filtration rate (GFR) was calculated using the CKD-EPI formula and cystatin C (Hoek's formula). The examination of visceral adipose tissue (VAT) was using an ultrasound method of investigation: the epi- and pericardial fat depots were assessed; VAT 1 – measurement at the level of the navel from the inner surface of the rectus abdominis to the posterior wall of the aorta and L4; VAT 2 – measurement at the level of the navel from the inner surface of the rectus abdominis to L4; the thickness of the posterior perirenal VAT on the right and left and the area of perirenal fat on both sides. Result The amount of fat depots in the groups is shown in Table 1. Indicators of hormonal activity of adipose tissue and renal markers are presented in Table 2. In the group with borderline hypertension the relationship between VAT 1 and 2 with ALT levels (r=0.40) and (r=0.42) was established, AST (r=0.52) and (r=0.47); HDL (r=−0.67) and (r=−0.70), TG (r=0.38) and (r=0, 39), HOMA index (r=0.45) and (r=0.39), MCP-1 (r=0.28) and (r=0.36). Perineal fat depot located to the right and left is correlated with LDL (r=0.40) and (r=0.37), glucose (r=0.49) and (r=0.50), ACRU (r=0.43) and (r=0.57), urinary excretion of cystatin C (r=0.28) and (r=0, 39). The connection with the optimal blood pressure level in control group was established between the perineal adipose tissue on the right and the left with the level of TG (r=0.35) and (r=0.29), GFR according to Hoek (r=0.29) and (r=0, 38), MCP-1 (r=0.36) and (r=0.29). Findings The increase of perinephral adipose tissue in obese patients is associated with an increase in cytokine excretion in the urine, an increase in VAT is accompanied by a deterioration in metabolic parameters. FUNDunding Acknowledgement Type of funding sources: None.


2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Christopher J. Stubbs ◽  
Ryan Larson ◽  
Douglas D. Cook

AbstractThe maize (Zea mays) stem is a biological structure that must balance both biotic and structural load bearing duties. These competing requirements are particularly relevant in the design of new bioenergy crops. Although increased stem digestibility is typically associated with a lower structural strength and higher propensity for lodging, with the right balance between structural and biological activities it may be possible to design crops that are high-yielding and have digestible biomass. This study investigates the hypothesis that geometric factors are much more influential in determining structural strength than tissue properties. To study these influences, both physical and in silico experiments were used. First, maize stems were tested in three-point bending. Specimen-specific finite element models were created based on x-ray computed tomography scans. Models were validated by comparison with experimental data. Sensitivity analyses were used to assess the influence of structural parameters such as geometric and material properties. As hypothesized, geometry was found to have a much stronger influence on structural stability than material properties. This information reinforces the notion that deficiencies in tissue strength could be offset by manipulation of stalk morphology, thus allowing the creation of stalks which are both resilient and digestible.


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