scholarly journals DEVELOPMENT AND TEST OF FREQUENCY SUBSECTION REGULATION SYSTEM FOR COMBINE HARVESTER HEADER CUTTER

2021 ◽  
pp. 283-292
Author(s):  
Ying Li ◽  
Zhuohuai Guan ◽  
Yisong Chen
Keyword(s):  
Regulation System ◽  
Maximum Relative Error ◽  
Forward Speed ◽  
Frequency Range ◽  
Adjustment Time ◽  
Optimum Cutting ◽  
Cutting Frequency ◽  
Combine Harvester ◽  
The Relationship ◽  
Trajectory Equation

Aiming at the problems that the cutter frequency of combine harvester is difficult to be adjusted adaptively with the forward speed, and that the missed cut or repeated cut may cause the harvesting loss to increase and the operation effect to fluctuate greatly, the system is designed to regulate the cutter frequency of combine harvester by sections. By constructing the cutter trajectory equation, the influence of the relationship between the forward speed of the harvester and the cutting frequency on the cutting area is analyzed, and the optimum cutting frequency range at different operating speeds is determined. The results show that the error between the actual cutting frequency and the desired frequency of the cutter is less than 0.8Hz, and the maximum relative error is less than 8.6%; the average steady-state adjustment time of the system is 1.3s when the input cutting frequency of the device changes abruptly. The research class provides technical support for the improvement of the combine harvester handling system and the increase of the machine automation level.

Effect of Vibration on Rapeseed Header Loss and Optimization of Header Frame

2021 ◽  
Vol 64 (4) ◽  
pp. 1247-1258
Author(s):  
Yang Li ◽  
Lizhang Xu ◽  
Zhipeng Gao ◽  
En Lu ◽  
Yaoming Li
Keyword(s):  
Modal Analysis ◽  
Engine Speed ◽  
Vibration Measurement ◽  
List Type ◽  
Positive Correlation ◽  
Combine Harvester ◽  
Analysis System ◽  
Combine Harvesters ◽  
Relationship Of ◽  
The Relationship

HighlightsThe relationship of vibration and header loss was studied by multi-point vibration measurement and loss collection test.There was an approximately linear positive correlation between total header vibration and total rapeseed header loss.The header frame was analyzed and optimized through modal simulation and testing.The total rapeseed header loss of the improved header was reduced by 33.2% to 46.9%.Abstract. In view of the current large rapeseed header losses of rape combine harvesters, the effects of the header on rapeseed header loss were studied from the perspective of vibration. First, the vibrations at various measuring points on the header during rape harvest were studied using a data acquisition and analysis system while performing collection tests of rapeseed header loss with the sample slot method. The relationships between total header vibration and total rapeseed header loss and between vertical cutter vibration and rapeseed vertical cutter loss were shown to have a positive correlation, and they all increased with the increase in engine speed. Vertical cutter loss accounted for 31.2% to 42.4% of the total rapeseed header loss. Modal analysis and optimization of the header frame were then performed by simulation and test. The natural frequencies of the first-order and second-order modes of the optimized header were increased, and the possibility of resonance with other working parts was eliminated. Finally, the improved header was tested during rape harvest. The results showed that the total vibration of the improved header was reduced by 19.9% to 43.9%, and the total rapeseed header loss was reduced by 33.2% to 46.9%. The vertical cutter vibration was reduced by 30.5% to 49.8%, and the rapeseed vertical cutter loss was reduced by 20.8% to 34.7%. In addition, the vibration and rapeseed loss of the improved header had relatively slow rates of increase with the increase in engine speed. The method of reducing rapeseed loss by reducing the header vibration achieved an obvious and positive effect. Keywords: Frame optimization, Modal analysis, Rape combine harvester, Rapeseed header loss, Vibration.

The relationship between group velocity and phase velocity for finite, discrete observations

1977 ◽  
Vol 67 (5) ◽  
pp. 1249-1258
Author(s):  
Douglas C. Nyman ◽  
Harsh K. Gupta ◽  
Mark Landisman
Keyword(s):  
Phase Velocity ◽  
Group Velocity ◽  
The Other ◽  
Frequency Range ◽  
Finite Frequency ◽  
Discrete Observations ◽  
Practical Situation ◽  
Order Polynomial ◽  
Observational Errors ◽  
The Relationship

abstract The well-known relationship between group velocity and phase velocity, 1/u = d/dω (ω/c), is adapted to the practical situation of discrete observations over a finite frequency range. The transformation of one quantity into the other is achieved in two steps: a low-order polynomial accounts for the dominant trends; the derivative/integral of the residual is evaluated by Fourier analysis. For observations of both group velocity and phase velocity, the requirement that they be mutually consistent can reduce observational errors. The method is also applicable to observations of eigenfrequency and group velocity as functions of normal-mode angular order.

scholarly journals The correlation of sociopsychological characteristics and self-stigmatization of patients with mental disorders (Result of original study)

2019 ◽  
pp. 46-54
Author(s):  
N. B. Lutova ◽  
O. V. Makarevich ◽  
K. E. Novikova
Keyword(s):  
Mental Disorders ◽  
Affective Disorders ◽  
Self Regulation ◽  
Personal Characteristics ◽  
Original Study ◽  
The Self ◽  
Regulation System ◽  
System Functioning ◽  
The Relationship ◽  
Self System

The investigation studies the relationship between narcissistic self-regulation with the features and expression of self-stigmatization in patients with endogenous mental disorders. The study involved 131 people, including patients with schizophrenia — 66.8% and individuals with affective disorders — 33.2%. The survey was conducted by using the following methods: «Index of Self-system functioning» and questionnaire of self-stigmatization by Mikhailova-Yastrebov. Data on correlation of strength personality reducing with selfstigmatization, the specifics of Self-regulation structure in various inner stigma forms, and the absence of IFSS significant differences in patient’s groups with different nosological forms of mental disorders, disease’s duration and number of hospitalizations — were obtained. The specific personal characteristics underlying premorbid changes in the Self-regulation system that determine the vulnerability of patients to the formation of stigma are discussed.

scholarly journals Researches on Grain Harvesting Machines

1970 ◽  
Vol 66 (1) ◽  
Author(s):  
Mariana DUMITRU
Keyword(s):  
Forward Speed ◽  
Combine Harvester ◽  
Made In ◽  
Main Factor

The purpose of the paper is to present some researches made on the mechanisms of the combine for cutting, feeding and threshing. There are presented the floating cutter bar, the combine with a spike-tooth cylinder and rotary separation, the combine with dual threshing and separating rotors. Some of the adjustments are made on the finger sensors for cutter bar. One of the most important adjustment is that made in order to reduce harvest loss. Forward speed is one of the main factor in optimizing the performance of a combine harvester. The method used in the paper is that of direct observing and measuring made on different component parts of combines.

scholarly journals Design and Simulation of the Operating Speed Regulation Algorithm of Plot Cabbage Seed Combine Harvester

2020 ◽  
Vol 11 ◽  
pp. 160-169
Author(s):  
Mao Hanping ◽  
Wang Jiahui ◽  
Xing Gaoyong ◽  
Zuo Zhiyu ◽  
Li Qinglin
Keyword(s):  
Association Rules ◽  
Sql Server ◽  
Forward Speed ◽  
Large Delay ◽  
Pid Algorithm ◽  
Speed Regulation ◽  
Control Scheme ◽  
Cabbage Seed ◽  
Combine Harvester ◽  
Feed Volume

Aiming at the problems of the single control scheme, the few aspects of monitoring and diagnosis, and the large delay time of the plot combine harvester, this paper designs the forward speed control algorithm of the plot Chinese cabbage seed harvester. This paper studies the theory of association rules, has used SQL Server to build a database including the job parameters of the main monitoring objects, and has mined the association rules between the job parameters and the feed amount through Analysis Service. Combining the knowledge of association rules and ordinary fuzzy PID algorithm, the article has built a model and performed simulation verification. The results show that the algorithm can adjust the forward speed reasonably and quickly when the feed volume increases.

Influence of Combine Harvester Forward and Reel Speeds on Wheat Harvesting Losses in Gezira Scheme (Sudan)

2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Omer A. Abdalla ◽  
Mohamed. H. Dahab ◽  
Mukhtar M. Musa ◽  
Eltayeb S. N. Babikir
Keyword(s):  
Technology Transfer ◽  
Total Yield ◽  
Forward Speed ◽  
Split Plot ◽  
Combine Harvester ◽  
Plot Design

The present study was conducted at the demonstration farm of Massaed Technology Transfer Center, Gezira State, during 2016/2017, to evaluate the effect of combine harvester forward and reel speed on wheat harvesting losses (total header, processing and total machine losses). Three combine harvester forward speeds (4, 5 and 6 km/h), and three reel speeds (25, 35 and 45 rpm) were used in the experiment, which was arranged in a split plot design with three replications. The results showed that forward speed 4 km/h with reel speed 25 rpm recorded the lowest total header losses (31.8 kg/ha) while the highest losses (90.1 kg/ha) was recorded by the forward speed 6 km/h and reel seed 25 rpm. The lowest processing losses was obtained from the forward speed 6 km/h with reel speed 25 rpm (13.2 kg/ha) while the highest was recorded by the forward speed 4 km/h with the reel speed 45 rpm (38.2 kg/ha). Forward speed 4 km/h with reel speed 25 rpm recorded the lowest total machine losses (56.7 kg/ha) which represents 9.5% of the total yield as compared to 118.0 kg/ha which represents 19.67% of the total yield recorded by the same speed with 45 rpm reel speed. It was concluded that the forward speed 4 km/h with reel speed 25 rpm was appropriate for reducing combined wheat harvesting losses under Gezira Scheme conditions.

scholarly journals Snow Stratigraphy and Water Equivalence Measured With an Active Microwave System

1980 ◽  
Vol 26 (94) ◽  
pp. 225-233
Author(s):  
D. A. Ellerbruch ◽  
H. S. Boyne
Keyword(s):  
Electromagnetic Scattering ◽  
Direct Determination ◽  
Snow Pack ◽  
Frequency Range ◽  
Microwave Radar ◽  
Snow Stratigraphy ◽  
Microwave System ◽  
The Relationship ◽  
System Operating

AbstractThis paper reports on research on the relationship between the electromagnetic scattering properties and physical properties of snow-pack. An FM-CW active microwave radar system operating in the frequency range 8-12 GHz is used to scatter electromagnetic radiation from surface and subsurface stratigraphic layers in the snow-pack. The amplitude of the scattered radiation as a function of depth in the snow-pack can be correlated with such physical characteristics as density, hardness, stratigraphy, and moisture content. A direct determination of snow-pack water equivalence can be made from these observations.

Some Observations on the Relationship Between Lubricant Mechanical and Dielectric Transitions Under Pressure

1980 ◽  
Vol 102 (2) ◽  
pp. 229-234 ◽  
Author(s):  
S. Bair ◽  
W. O. Winer
Keyword(s):  
Atmospheric Pressure ◽  
Frequency Range ◽  
Two Fluids ◽  
Constant Rate ◽  
Constant Viscosity ◽  
The Relationship ◽  
Dielectric Transition

Viscoelastic transition measurements of several lubricants by volume dilatometry to pressures of 1.75 GPa, dielectric transitions at atmospheric pressure on five fluids in a frequency range of 0.2 to 500 kHz and on two fluids in the same frequency range to pressures of 0.55 GPa are reported. Lines of constant rate dilatometry transition, constant rate dielectric transition and constant viscosity are shown to be essentially parallel on a temperature-pressure diagram.

Dielectric Property of Laminated AlN/BN Ceramic Composites

2009 ◽  
Vol 620-622 ◽  
pp. 359-362
Author(s):  
Tao Zhang ◽  
Hai Yun Jin ◽  
Rui Zhou ◽  
Ji Feng Zhao ◽  
Zhi Hao Jin
Keyword(s):  
Dielectric Property ◽  
Dielectric Loss ◽  
Low Frequency ◽  
Ceramic Composites ◽  
Space Charge Polarization ◽  
Frequency Range ◽  
Pressing Temperature ◽  
Polarization Mechanism ◽  
The Relationship ◽  
Dielectric Loss Increase

The relationship between the processing technology and the dielectric property of the laminated AlN/h-BN ceramic composites has been studied. The results showed that the main polarization mechanism of laminated ceramic composites in low frequency range is space charge polarization at the interface of AlN layer and BN layer. Due to the affection of porosity, the permittivity increases and the dielectric loss decreases with increasing the hot pressing temperature. The permittivity increases and the dielectric loss decreases with increasing thickness ratio of different layer., Both permittivity and dielectric loss increase with increasing the content of AlN doping in BN layer.

scholarly journals Variations in β(T)-function due to addition of LiI-4AgI system

2017 ◽  
Vol 22 (2) ◽  
pp. 113
Author(s):  
Carlos Alberto Lozano Zapata ◽  
Diego Peña Lara ◽  
Hernando Correa Gallego
Keyword(s):  
Silver Iodide ◽  
Relaxation Function ◽  
Migration Energy ◽  
Frequency Range ◽  
Weak Correlation ◽  
Pure Compound ◽  
And Migration ◽  
Mobile Ions ◽  
The Relationship ◽  
Microscopic Energy

Impedance spectroscopy measurements of the LiI-4AgI samples, in the frequency range 20 Hz{1 MHz, and in the temperature range between 353 K and 378 K were made. Both pure and lithium-doped silver iodide showed blocking phenomena in the electrodes and the grain boundary. The blocking phenomena allowed a change in the transport properties of the pure compound in respect to the doped compound as the temperature varied. The curves of electrical modulus in the LiI-4AgI system show asymmetric peaks corresponding with a weak correlation between mobile ions in the diusion process. The electrical conductivity in the AgI-LiI system can be described using a stretched relaxation function of the Kohlrausch-Williams-Watts (KWW) type. We speculat e that the phase of lithium dissolved in the silver iodide favors the formation of islands that disperses the conductivity due to the modication of the relationship among the microscopic energies: microscopic energy and migration energy.

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