scholarly journals ИССЛЕДОВАНИЕ ВЫГРУЗКИ ТРАНСПОРТНЫХ СРЕДСТВ ПРИ УБОРКЕ КАРТОФЕЛЯ

2019 ◽  
Author(s):  
D.S. Ryabchikov ◽  
S.N. Borychev ◽  
M.Yu. Kostenko ◽  
R.V. Beznosyuk ◽  
G.A. Borisov ◽  
...  
Keyword(s):  
Kinetic Energy ◽  
Significant Role ◽  
Theoretical Calculations ◽  
Mechanical Damage ◽  
The Body ◽  
Angle Of Repose ◽  
Heavy Trucks ◽  
Dump Trucks ◽  
Final Speed ◽  
Shock Pulses

Уборка картофеля предполагает транспортировку клубней с поля до хранилищ. Транспортные средства для перевозки картофеля весьма разнообразны и разнотипны это и автомашинысамосвалы, тракторные самосвальные прицепы, автомашины с полуприцепами и контейнеровозы. В большинстве картофелеводческих хозяйств площади, занятые под картофель, не превышают 300 га, а для транспортировки урожая применяют большегрузные самосвалы. Выгрузка картофеля из кузова происходит в результате подъемаопрокидывания, что приводит к образованию гравитационных потоков клубней и способствует появлению механических повреждений клубней. Взаимодействия клубней при выгрузке генерируют напряжения в насыпи картофеля за счет передачи ударных импульсов. В работе исследуется процесс скатывания одиночных клубней по насыпи картофеля. Анализ движения единичных клубней по насыпи показал, что качение клубня происходит при достаточной силе трения под углом естественного откоса. Наибольшее влияние на кинетическую энергию системы будет оказывать путь, пройдённый клубнем по насыпи чем больше путь, тем больше энергия. Значительную роль будет оказывать также конечная скорость клубня. Снизить кинетическую энергию клубня можно, уменьшая участок разгона с помощью установки дополнительных препятствий в кузове, например, поперечной перегородки. Для уточнения теоретических выкладок был проведен эксперимент по выгрузке клубней из контейнера без перегородки и оборудованного поперечной перегородкой. В ходе эксперимента изучались раскат клубней от контейнера, характеризующий скорость клубней при скатывании по насыпи, и остаток клубней в кузове, характеризующий скорость выгрузки клубней. Установлено, что дополнительные поперечные перегородки способствуют снижению кинетической энергии картофеля при выгрузке и снижают механические повреждения клубней.Harvesting potatoes involves transporting tubers from the field to storage. Vehicles for transporting potatoes are very diverse and diverse these are dump trucks, tractor dump trailers, trucks with semitrailers and container carriers. In most potato farms, the area occupied by potatoes does not exceed 300 hectares, and heavy trucks are used to transport the crop. Unloading of potatoes from the body occurs as a result of lifting tipping, which leads to the formation of gravitational flows of tubers and contributes to the appearance of mechanical damage to tubers. The interactions of the tubers during unloading generate stresses in the embankment of the potato due to the transmission of shock pulses. We investigate the rolling of single tubers over a mound of potatoes. Analysis of the movement of individual tubers along the embankment showed that the tuber rolls with sufficient friction at an angle of repose. the kinetic energy of the system will be most affected by the path traveled by the tuber through the embankment the larger the path, the greater the energy. The final speed of the tuber will also play a significant role. Reducing the kinetic energy of the tuber, it is possible to reduce the acceleration area by installing additional obstacles in the body, for example, a transverse partition. To clarify the theoretical calculations, an experiment was conducted to unload tubers from a container without a partition and equipped with a transverse partition. During the experiment, the tuber roll from the container was studied, which characterizes the speed of the tubers when rolling along the embankment, and the remainder of the tubers in the back, which characterizes the speed of unloading the tubers. Additional transverse partitions have been established that contribute to a decrease in the kinetic energy of potatoes during unloading and reduce mechanical damage to tubers.

A Good Sentencing Precedent is Hard to Find

2020 ◽  
Vol 32 (3) ◽  
pp. 138-144
Author(s):  
Brian A. Jacobs
Keyword(s):  
United States ◽  
Significant Role ◽  
College Admissions ◽  
The Body ◽  
Federal Law ◽  
Criminal Cases ◽  
Federal Sentencing

In federal criminal cases, federal law requires that judges consider the sentences other courts have imposed in factually similar matters. Courts and parties, however, face significant challenges in finding applicable sentencing precedents because judges do not typically issue written sentencing opinions, and transcripts of sentencings are not readily available in advanced searchable databases. At the same time, particularly since the Supreme Court’s 2005 decision in United States v. Booker, sentencing precedent has come to play a significant role in federal sentencing proceedings. By way of example, this article discusses recent cases involving defendants with gambling addictions, and recent cases involving college admissions or testing fraud. The article explores the ways the parties in those cases have used sentencing precedent in their advocacy, as well as the ways the courts involved have used sentencing precedent to justify their decisions. Given the important role of sentencing precedent in federal criminal cases, the article finally looks at ways in which the body of sentencing law could be made more readily available to parties and courts alike.

Concept of Artavavaha Srotas

2016 ◽  
Vol 1 (2) ◽  
Author(s):  
Dr. Shraddha Singh ◽  
Shivaji Pawar ◽  
Preeti Sahu
Keyword(s):  
Significant Role ◽  
The Body ◽  
Pathological Changes ◽  
Disease Condition

In Ayurveda, the concept of Srotas has been propagated very specifically. They are integral part of the body. Body is composed of numerous Srotas which have a significant role in maintenance of equilibrium of body elements. They are responsible for maintenance of health as well as disease condition. Srotas is a channel through which different elements undergo transformation, circulation and transportation. Pathological changes occurs in the body due to Srotodushti, Srotosanga etc.

Moving Cage: Vibration, Sonification and the Quanta of Time

2021 ◽  
Vol 46 (2) ◽  
pp. 169-183
Author(s):  
MARCUS CHENG CHYE TAN
Keyword(s):  
Kinetic Energy ◽  
The Body ◽  
Dance Movements ◽  
Politics Of The Body

Dear John is an experimental choreomusical work that reinterprets Cage's works while advancing his ideas of sound as sonic events and embodied choreography. In this episodic work, improvised movement unfolds to a soundscape of defamiliarized instruments, sound devices and sonicities of macro- and micro-movements. The correspondence and (in)congruence between dance movements and music's kinetic energy become the means to examine a politics of the body and sound, of music on movement. Additionally, in this ‘auditory architecture’ the quanta of time, its relations and (lack of) unity are exposed. This article then examines the intersubjective interplay of movement and music, body and sonicity; it considers the resonance of the performing body as intermaterial vibration and how this invites a sonic politics of relational possibility. The article will then also investigate the ways in which the interaction of motion and music, movement and stillness engenders experiences of time's indeterminacy and elasticity.

scholarly journals Patient education on back care

2009 ◽  
Vol 65 (1) ◽  
Author(s):  
C. Van Eck
Keyword(s):  
Low Back Pain ◽  
Back Pain ◽  
Patient Education ◽  
Study Design ◽  
Significant Role ◽  
The Body ◽  
Low Back ◽  
Clinical Perspective ◽  
Back Care ◽  
External Forces

Study Design: Clinical PerspectiveObjective: To provide back care education for patients with low back pain. Background:  Understanding the internal and external forces the body issubjected to, as well as the spine’s response to these forces, can better equipphysiotherapists in educating patients with low back pain. Methods and Measures: The focus of the clinical perspective is to providephysiotherapists with clinically sound reasoning when educating patients. Results: Providing a patient handout, educating them in how to incorporate back care knowledge into their dailyactivities.Conclusion: Physiotherapists can play a significant role in empowering patients through education to take responsi-bility for their disability.

scholarly journals The theory of the chain fountain revisited

2021 ◽  
Vol 2090 (1) ◽  
pp. 012166
Author(s):  
Dragos-Victor Anghel
Keyword(s):  
Energy Transfer ◽  
Kinetic Energy ◽  
Significant Role ◽  
Mechanical Work ◽  
Scientific Consensus ◽  
Energy And Momentum ◽  
Work Done

Abstract We analyze the chain fountain effect-the chain siphoning when falling from a container onto the floor. We argue that the main reason for this effect is the inertia of the chain, whereas the momentum received by the beads of the chain from the bottom of the container (typically called “kicks”) plays no significant role. The inertia of the chain leads to an effect similar to pulling the chain over a pulley placed up in the air, above the container. In another model (the so called “scientific consensus”), it was assumed that up to half of the mechanical work done by the tension in the chain may be wasted when transformed into kinetic energy during the pickup process. This prevented the chain to rise unless the energy transfer in the pickup process is improved by the “kicks” from the bottom of the container. Here we show that the “kicks” are unnecessary and both, energy and momentum are conserved-as they should be, in the absence of dissipation-if one properly considers the tension and the movement of the chain. By doing so, we conclude that the velocity acquired by the chain is high enough to produce the fountain effect. Simple experiments validate our model and certain configurations produce the highest chain fountain, although “kicks” are impossible.

Optimal Self-Propulsion of a Deformable Prolate Spheroid

1983 ◽  
Vol 27 (02) ◽  
pp. 121-130
Author(s):  
T. Miloh
Keyword(s):  
Kinetic Energy ◽  
Surface Deformation ◽  
Deformable Body ◽  
Large Degree ◽  
Prolate Spheroid ◽  
The Body ◽  
Deformation Pattern ◽  
Inviscid Fluid ◽  
Periodic Surface ◽  
Deformation Velocity

The problem of self-propulsion of an elongated deformable body moving in an infinite medium of inviscid fluid is considered in some detail. A prolate spheroid is chosen as a model shape, and a particular deformation pattern which maximizes the Froude efficiency is sought. The Froude efficiency in this context is defined by the ratio of the kinetic energy of the body to the total kinetic energy of the system comprising the body and the fluid. It is demonstrated that a body can propel itself from rest in a persistent manner even for a periodic surface deformation with zero mean which preserves both the volume and the location of its centroid. Under these constraints the induced forward velocity of the body is of 0(ε2) where ε is the amplitude of the deformation velocity. It is also demonstrated that for a persistent self-propulsion to exist the body should develop a large degree of skewness, resulting from the interaction between the two deformation components—one with fore-and-aft symmetry and one without. It is also essential that the symmetric and asymmetric deformation components should be out of phase.

Paper 7. Unsteady Flow around a Slender Fish-Like Body

1972 ◽  
Vol 14 (7) ◽  
pp. 43-52 ◽  
Author(s):  
Th. Y. Wu ◽  
J. N. Newman
Keyword(s):  
Unsteady Flow ◽  
Theoretical Calculations ◽  
Cross Flow ◽  
Vortex Sheet ◽  
The Body ◽  
Dynamic Force ◽  
Cross Sectional ◽  
Vortex Sheets ◽  
Flat Fish ◽  
The Cross

This paper attempts to extend some recent theoretical calculations on the unsteady flow generated by body movements of a slender ‘flat’ fish by further including the effect of finite body thickness in the consideration for various configurations of side and caudal fins as major appendages. Based on the slender-body approximation, the cross-flow is determined for different longitudinal body sections which are characterized by a variety of cross-sectional shapes and flow conditions (such as having smooth or fin-edged body contours, with or without vortex sheets alongside the body section). The effect of body thickness is found to arise primarily from its interaction with the vortex sheet already existing in the cross-flow. New results for the transverse hydro-dynamic force acting on the body are obtained, and their physical significances are discussed.

The Application of Eddy-Viscosity Stress Limiters for Modeling Cross-Flow Separation

2010 ◽  
Vol 132 (9) ◽  
Author(s):  
P. A. Gregory ◽  
P. N. Joubert ◽  
M. S. Chong ◽  
A. Ooi
Keyword(s):  
Kinetic Energy ◽  
Skin Friction ◽  
Turbulent Kinetic Energy ◽  
Flow Separation ◽  
Eddy Viscosity ◽  
Cross Flow ◽  
The Body ◽  
Mean Flow ◽  
Viscosity Models ◽  
Experimental Apparatus

The ability of eddy-viscosity models to simulate the turbulent wake produced by cross-flow separation over a curved body of revolution is assessed. The results obtained using the standard k−ω model show excessive levels of turbulent kinetic energy k in the vicinity of the stagnation point at the nose of the body. Additionally, high levels of k are observed throughout the wake. Enforcing laminar flow upstream of the nose (which replicates the experimental apparatus more accurately) gives more accurate estimates of k throughout the flowfield. A stress limiter in the form of Durbin’s T-limit modification for eddy-viscosity models is implemented for the k−ω model, and its effect on the computed surface pressures, skin friction, and surface flow features is assessed. Additionally, the effect of the T-limit modification on both the mean flow and the turbulent flow quantities within the wake is also examined. The use of the T-limit modification gives significant improvements in predicted levels of turbulent kinetic energy and Reynolds stresses within the wake. However, predicted values of skin friction in regions of attached flow become up to 50% greater than the experimental values when the T-limit is used. This is due to higher values of near-wall turbulence being created with the T-limit.

scholarly journals Effect of water medium upon the process of ore disintegration in wet self-grinding mills

2019 ◽  
Vol 109 ◽  
pp. 00058
Author(s):  
Vitalii Monastyrskyi ◽  
Serhii Monastyrskyi ◽  
Borys Mostovyi
Keyword(s):  
Aquatic Environment ◽  
Experimental Studies ◽  
The Body ◽  
Angle Of Repose ◽  
Hydrodynamic Resistance ◽  
Uniform Structure ◽  
Water Medium ◽  
Large Piece ◽  
Grinding Mills ◽  
Expansion Force

This article presents the results of theoretical and experimental studies on the processes of destruction ore in wet self-grinding mills under the influence of the aquatic environment on it. The equivalent circuit for determining the stress-strain state of a large piece (ball) exposed to the load at an angle of repose of the material in motion are justified. A uniformly distributed pressure acts on the body of arbitrary shape, depending on the hydrostatic pressure of the pulp inside the drum and the force of hydrodynamic resistance). It is assumed that a large piece has the shape of a sphere with a uniform structure, but in some of its parts there are cavities filled with an incompressible fluid. Under the action of these forces inside the cavity wedging effects of water occur, the effect of which on the strength ores depends on the expansion force and the angle of the micro crack. The experimental researches are done under laboratory and industrial conditions. It was established that the disintegration of kimberlitic ore in MMC is significantly influenced by the characteristics of the aquatic environment pH and Eh, the values of which vary from 3.2 to 7.0 and from -500 to +1020 mV.

Design of a Logging Tool Valve Based on Finite Element Analysis

2012 ◽  
Vol 189 ◽  
pp. 411-414
Author(s):  
Min Qiang Dai ◽  
Sheng Dun Zhao ◽  
Wei Cai
Keyword(s):  
Theoretical Calculations ◽  
High Reliability ◽  
Control Valve ◽  
Simulation Software ◽  
The Body ◽  
Process Equipment ◽  
Hydraulic Control ◽  
Element Analysis ◽  
Dual Channel ◽  
Working Principle

The paper introduces the working principle of a logging instrument, and according to the working principle and instrument’s function of two-way hydraulic control valve. Facing to the key problems of process equipment in the actual service and workflow, the structure of value was designed and optimized. According to the basic functions and physical model of dual-channel and two-way hydraulic control valves, we used hydraulic system simulation software to establish the mathematical model of the entire system. Besides, we maked the simulation of the running state based on the Running results. At the same time, on the grounds of theoretical calculations and simulation results, the influences of the body affected by the external factors in work environment were assessed, and the logging instrument with a dual-channel and two-way hydraulic control valve is designed and processed. Meanwhile, we build an experimental platform and make the experiment according to principle of the instrument. The results show that the design of this dual-channel and two-way hydraulic control valve logging instrument met the work requirements, and it has high reliability in oil exploration, which could be promoted and used in logging areas.

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