scholarly journals Influence Analysis of Factors Related to the Clod Heaping Quantity of Subsoilers

2020 ◽  
pp. 217-226
Author(s):  
Sin Kwang Gyun ◽  
Ri CholUk ◽  
Cha Jin Myong ◽  
Ri SungIl ◽  
Ri YongIl ◽  
...  
Keyword(s):  
Field Study ◽  
Middle Part ◽  
Optimum Operating ◽  
Operating Speed ◽  
Optimum Level ◽  
Response Model ◽  
Clay Loam ◽  
Front Part ◽  
Compound Structure ◽  
Rear Part

In order to increase the performance of three working parts of this machine at the same time, it needs to increase its operating speed, 1MG11-200type compound paddy tiller consists of the mounted compound structure arranged the subsoiler with cutting edge at the front part and rotary-tiller without power in the middle part and curved tooth-beam harrow in the rear part, this be able to plough and harrow and level at a time. As operating speed increases in clay loam, the clod heaping occurs in the space of subsoilers, even fill up in the spaces. Therefore, during the working, it is one of important matter to found the optimum operating speed and subsoiler’s interval without clod heaping. In a field study conducted at MiGok co-op farm, Sariwon, Democratic People’s Republic of Korea, were tested for clod heaping quantity on different operating speed and subsoiler’s intervals for clay loam. Mathematical response model was built on clod heaping quantity relative to operating speed and subsoiler’s interval to found the operating levels without clod heaping. It was found that the subsoiler, while working in clay loam, should have operating speed 6.2km/h, subsoiler’s side interval 0.5m and subsoiler’s front-rear interval 0.46m for optimum level without clod heaping.

A fragmentation-spreading model for long-runout rock avalanches

1999 ◽  
Vol 36 (6) ◽  
pp. 1096-1110 ◽  
Author(s):  
T R Davies ◽  
M J McSaveney ◽  
K A Hodgson
Keyword(s):  
Rock Mass ◽  
High Velocity ◽  
Rock Fragmentation ◽  
Front Part ◽  
Long Runout ◽  
Spreading Model ◽  
Rock Avalanches ◽  
Rear Part ◽  
Dispersive Stress

Based on the observation that deposits of large rock avalanches consist predominantly of intensely fragmented rock debris, it is proposed that the processes of rock fragmentation are significant causes of the peculiar distribution of mass in these deposits, and of the correspondingly long runout. Rock fragmentation produces high-velocity fragments moving in all directions, resulting in an isotropic dispersive stress within the translating rock mass. A longitudinal dispersive force consequently acts in the direction of reducing mass depth and tends to cause the rear part of the avalanche to decelerate and halt and the front part to accelerate. The result is greater longitudinal spreading of the travelling mass compared with nonfragmenting granular avalanches. The longer runout results from this additional fragmentation-induced spreading.

Design and Analysis of Anti-Radiation Computer Mouse and Keyboard

2013 ◽  
Vol 333-335 ◽  
pp. 2093-2096
Author(s):  
Zhi Wu Gai ◽  
Hong Lin ◽  
Teng Zeng
Keyword(s):  
Electromagnetic Radiation ◽  
Control Circuit ◽  
Computer Users ◽  
Front Part ◽  
Radiation Problem ◽  
Push Button ◽  
Computer Mouse ◽  
Rear Part ◽  
Left And Right ◽  
Computer Keyboard

In order to solve the electromagnetic radiation problem of traditional computer mouse and computer keyboard, we disclose sets of new anti-radiation computer mouse and computer keyboard. These anti-radiation computer mouse and keyboard are specially designed in frame and enclosure. The mouse shell is divided into front and rear part, or segregated two enclosures by shielding board in mouse shell. The circuit of mouse is set in front part of the mouse. Left and right push-button and manual rollers are set in rear part of mouse. The control circuit of keyboard is detached from it and set in a card that can be plug in expansion slot of computer. Circuit is the source of electromagnetic radiation. Thus, the sources of electromagnetic radiation are far from your hand during your operation. Furthermore, by taking shielding and absorbing precautions, these new anti-radiation mouse and keyboard have hardly any radiation at all, no secret information will leak out, and will not do harm to your health. They have all the advantages of traditional computer mouse and keyboard, and much more than this, they are anti-radiation. These anti-radiation computer mouse and keyboard are green products, have no radiation to computer users.

scholarly journals Seeding uniformity for vacuum precision seeders

2008 ◽  
Vol 65 (3) ◽  
pp. 318-322 ◽  
Author(s):  
Ali Musa Bozdoğan
Keyword(s):  
Field Study ◽  
Operating Speed ◽  
Seed Spacing

The performance of three vacuum precision seeders was investigated in a field study. Seeding uniformity was determined in three different within-row distances: 14, 18 and 21 cm. The seeders were operated at 1.8, 3.6, 5.4 and 7.2 km h-1. Successive seed spacing along of 3 m of row was measured in three replications on each row. For evaluating the seeding uniformity of seeders, seed spacings were analyzed using the methods (MISS, MULT, QFI and PREC). There were no differences between seeders. For P < 0.01, operating speed affected MISS and QFI values, and the within-row seed spacing affected MULT and PREC values. The best operating speed was 1.8 km h-1 because of the highest QFI value (88.5%). There was no difference between 1.8 and 3.6 km h-1. The speeds, 1.8 and 3.6 km h-1, were different from 5.4 and 7.2 km h-1. The best within-row distance was 18 cm because the QFI value was higher than those of 14 and 20 cm, 86.9%, 82.0% and 81.8%, respectively. The best PREC value was obtained for 21 cm within-row distance (17.4%). PREC values were acceptable for precision seeding in all trials.

Charge Contrast Imaging of Gibbsite Using the Variable Pressure SEM

2004 ◽  
Vol 10 (6) ◽  
pp. 721-732 ◽  
Author(s):  
Kevin Robertson ◽  
Raynald Gauvin ◽  
James Finch
Keyword(s):  
Charge Compensation ◽  
Beam Current ◽  
Ion Flux ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Variable Pressure ◽  
Optimum Level ◽  
Contrast Imaging ◽  
Optimum Specimen ◽  
Working Distance

The variable pressure scanning electron microscope (VP-SEM) allows imaging of insulators without the need for a conductive coating, due to charge neutralization at the surface from recombination of positive ions and surface electrons. Varying certain parameters such as pressure, bias, and working distance creates incomplete neutralization, and localized charging develops called charge contrast. Although the exact mechanism creating charge contrast imaging (CCI) is unknown, it is agreed that it is related to an optimum charge compensation. The behavior of the CCI is still vague, which presents a problem for determining the mechanisms. This article provides user-friendly methods of finding the optimum levels of charge contrast in the VP-SEM. We show that the CCI is obtained at optimum operating conditions where the specimen current is between 2.5 nA and 3.5 nA. The specimen current is a function of secondary electrons (SE) emission and ionization potential, producing an ion flux. Therefore an optimum specimen current represents the balanced conditions of SE emission and ion flux. Controlling the pressure, working distance, bias, scan rate, and beam current allows the microscopist to set the specimen current at this optimum level for charge contrast imaging. All the work was performed on gibbsite using the S3000N VP-SEM from Hitachi.

Principal Considerations on Tire Wear

1956 ◽  
Vol 29 (3) ◽  
pp. 781-788 ◽  
Author(s):  
A. Schallamach
Keyword(s):  
Tangential Stress ◽  
Relative Motion ◽  
Velocity Component ◽  
Model Experiment ◽  
Elasticity Problem ◽  
Front Part ◽  
Side Force ◽  
Tire Wear ◽  
Rear Part ◽  
Common Area

Abstract The prerequisite for tire wear is relative motion between the tire and road in their common area of contact. Such relative motion occurs, for example, when a tire is flattened on entering the area of contact and can also take place when the tire exerts a force on the ground, i.e., during propulsion, braking and, particularly, cornering. The mechanism of abrasion when the wheel is not rolling freely becomes complicated by the fact that, because of the elasticity of the tire, its circumferential velocity with respect to the vehicle can differ from the travelling velocity, and that, furthermore, the tire can have a velocity component normal to its plane without skidding. In other words, slip without noticeable abrasion is possible. The only case discussed here will be when the wheel describes a curved path. The elasticity problem involved has been treated, among others, by Fromm, von Schlippe, and Temple; the essential facts are best visualized by means of the model experiment reproduced in Figure 1. In this experiment, a solid rubber wheel rolled around a Perspex disk, and the area of contact was illuminated by internal reflection. The deformation of the equator (marked in black) shows that two regions can be distinguished in the area of contact. In the front part, the equator is distorted into a curve parallel to the path, i.e., into a circle, and one can easily see that no relative motion between wheel and track occurs here, but that the wheel adheres to the track. The tangential stress necessary to deflect the wheel is maintained by friction until the stress becomes so high that the limiting friction is reached. At this point the second or rear part of the area of contact develops, in which the wheel slides back sideways. Abrasion should, therefore, be expected only in the rear part of the area of contact. It will decrease with increasing elasticity of the tire, but nothing will be gained thereby, since the tire has, after all, to take up the forces arising during driving. In the present case, this involves the side force holding the vehicle on the curve, and what matters is the dependence of abrasion on this side force.

scholarly journals Effects of some test parameters on dehulling efficiency of a roasted groundnut seed dehulling machine

2020 ◽  
Vol 5 (5) ◽  
pp. 024-029
Author(s):  
Abiodun Samson Olubo ◽  
Joseph Temitope Stephen ◽  
Adebayo Adeyinka ◽  
Opeyemi Olusegun Opadotun
Keyword(s):  
Moisture Content ◽  
Nutritional Value ◽  
Large Scale ◽  
Optimum Operating ◽  
Operating Speed ◽  
Optimum Operating Condition ◽  
Oil Seed ◽  
Test Parameters ◽  
Seed Husk ◽  
Dehulling Efficiency

Groundnut (Arachis hypogeae. L) is an important oil seed grown in over 100 countries for its nutritional value. In order to improve its storability and value, various ways of processing the seeds have been adopted among which is the roasting and removal of husk or rind from the roasted groundnuts. The process of removing of groundnut husk is mostly done manually and inappropriate for large scale processing. In order to improve groundnut seed husk dehulling process through mechanization, a roasted groundnut seed dehulling machine was developed and the effects of operating speed of the machine and moisture content of the seed on the on the efficiency of the machine was studied. 1kg of the roasted groundnut in five replicates with moisture content of 1.4, 1.6, 1.8, 2.0 and 2.2 % (w.b) respectively, was fed into the machine at different speed of 30, 35, 40, 45 and 50 rpm for each replicate. The machine had the best dehulling efficiencies of 80%, 78%, 77%, 90% and 73% at the lowest speed (30 rpm) while the lowest efficiency of 57%, 49%, 53%, 52% and 46% was recorded at the highest speed (50 rpm) in all moisture content (1.4, 1.6, 1.8, 2.0 and 2.2%) respectively. The best performance efficiency of 90% was gotten at 30 rpm and moisture content of 2.0 % (w.b). Hence, an optimum operating condition was established for the machine.

Herbaceous Weed Control with Hexazinone in Loblolly Pine (Pinus taeda) Plantations

Weed Science ◽  
1979 ◽  
Vol 27 (6) ◽  
pp. 583-588 ◽  
Author(s):  
C. H. Fitzgerald ◽  
J. C. Fortson
Keyword(s):  
Field Study ◽  
Pinus Taeda ◽  
Weed Control ◽  
Loblolly Pine ◽  
Activated Charcoal ◽  
Sandy Loam ◽  
Seedling Height ◽  
Clay Loam ◽  
Pine Seedlings ◽  
Herbaceous Weed Control

Hexazinone [3-cyclohexyl-6-(dimethylamino)-1-methyl-1,3,5-triazine-2,4 (1H, 3H)-dione] effectively controlled herbaceous weeds in a loblolly pine (Pinus taeda L.) plantation in 1975. Pine seedling height increased as a result of weed control following 1 to 3 kg/ha applications but phytotoxic symptoms were evident. A 1976 field study indicated activated charcoal root coatings may reduce phytotoxic action. Hexazinone at 3 and 4 kg/ha applied to either the foliage or the soil was toxic to potted pine seedlings in 1976. The addition of surfactant to hexazinone treatments at 2, 3, and 4 kg/ha increased pine phytotoxicity to unacceptable levels. When hexazinone was applied to soil at 2, 3, and 4 kg/ha, activated charcoal root coatings reduced pine mortality to acceptable levels on Norfolk sandy loam. Charcoal was less effective on Madison clay loam. Pine tolerance on both soils was acceptable at 2 kg/ha.

scholarly journals Influence of Road Roughness Wavelengths on Bus Passengers' Oscillatory Comfort

2020 ◽  
Vol 25 (1) ◽  
pp. 41-53
Author(s):  
Dragan Sekulic
Keyword(s):  
Degrees Of Freedom ◽  
Narrow Range ◽  
Good Condition ◽  
Middle Part ◽  
Mean Square ◽  
Road Roughness ◽  
Rear Part ◽  
Vertical Accelerations ◽  
Vertical Vibrations ◽  
Iso 2631

This paper analyses the effect of the waviness parameter w on the oscillatory comfort of bus passengers for one road in good condition. The analysis is carried out by a validated nonlinear oscillatory 16 degrees of freedom (DOF) bus model defined in the software Matlab/Simulink and procedure from ISO 2631/1997 standard. The root-mean-square (RMS) values of the weighted vertical accelerations from the passengers' seats increase with the increase in the parameter w. On the other hand, the RMS values of the weighted vertical accelerations from bus floor decreased with the increase in the parameter w. The best oscillatory comfort has a passenger in the middle part of the bus, and the worst has a passenger in the rear part of the bus. The intensities of the vertical accelerations from the bus floor are mainly concentrated into two frequency ranges, 0÷2.5 Hz and 5÷10Hz. The passenger seats are dampened with vertical vibrations above 4~Hz. For the narrow range w=1.5÷2.3, nominal value of the waviness parameter (w=2) is sufficiently precise in assessment of the bus passengers' oscillatory comfort.

Application of Computational Fluid Dynamics for Optimization of Grid Flocculation Tank

2016 ◽  
Vol 13 (10) ◽  
pp. 6457-6462
Author(s):  
Jianlin Liu ◽  
Qing Chang ◽  
Zhongshen Yi
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Middle Part ◽  
Front Part ◽  
Terminal Part ◽  
Turbulent Dissipation ◽  
Average Value ◽  
Treatment Processes ◽  
Successful Design ◽  
Computational Fluid Dynamics Cfd

Flocculation is a very important component of the overall suite of treatment processes. The need for a profound understanding and successful design/optimization of flocculation processes is important since the requirements for the removal of particulates have become increasingly stringent. The computational fluid dynamics (CFD) was used to design the flocculating tanks. The values of turbulent kinetic energy (k), turbulent dissipation rate (ε) and velocity gradient (G) were employed to evaluate the parameters of the flocculation tank using the realizable k − ε model. The best size of the grid in the front part of the tank was 80 mm × 80 mm. In this condition, the average value of k and ε were 0.00152 m2/s2 and 0.000570 m2/s3, respectively, and the percentage of G in the range of 70–100/s was 35.5%. For the middle part of the tank, the best size of the grid was 110 mm × 110 mm, with the average value of k and ε, as well as the percentage of G in the range of 40–60/s, were 0.00167 m2/s2, 0.000568 m2/s3 and 34.3%, respectively. In order to protect the flocs from being broken by stir, there was no grid in the terminal part of the tank. The optimized slice gap for both of the front part and the middle part of the tank were 600 mm.

scholarly journals Rationale for vehicle parameters for the transportation of straw and hay

2021 ◽  
Vol 37 ◽  
pp. 00037
Author(s):  
Andrey Babkov ◽  
Vladimir Varavin
Keyword(s):  
Mechanical Properties ◽  
Physical And Mechanical Properties ◽  
Load Resistance ◽  
Front Part ◽  
Rear Part ◽  
The Coefficient Of Friction ◽  
Transport Vehicle ◽  
Oat Straw ◽  
Loading And Unloading ◽  
Finger Tip

Vehicles for the transportation of straw and hay in loose and pressed forms are considered. A scheme of a transport vehicle for the transportation of straw and hay, a haystack truck, is proposed. The haystack truck consists of a frame, wheels, a trailer device, a finger platform, a mechanism for loweringlifting the front part of the platform, sides, a mechanism for lowering-lifting the rear part of the platform. The results of studies to determine the physical and mechanical properties of straw and hay, necessary to rationale the parameters of the haystack platform, are presented. The dependence of the coefficient of friction of oat straw, barley, winter wheat, millet, buckwheat and alfalfa hay and awnless brome on the fingers of the haystack and loading and unloading surfaces: soil, sod, asphalt, straw, crushed stone on the load and speed is presented. The dependence of the resistance to the introduction of the finger tip of the haystack platform into the straw on the density of the material and the dependence of the load resistance of the vehicle on the angle of inclination of the platform are shown. The results of determining the angles of inclination of the haystack platform during loading, transportation and unloading of straw and hay stacks are presented. Recommendations on the use of a self-loading haystack truck for transporting straw and hay in loose and pressed form are given.

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