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Mohamad reza bayati ,( M,SC)
ABSTRACT : Automatic guidance of tractors in the mechanized farming practice has taken the attention of agricultural engineers in the last two decades .for this to be truly practical on the farm, it should be economical, simple to operate, and entirely contained on the vehicle. steering automation has been implemented successfully on agricultural vehicles on the basis of analog-type components, i,e. sensors, controllers, and actuator elements. Different types of steering systems such as leader-cable, laser-controlled, radio-operated, and contactor type have been developed for automatic guidance. The present study was aimed to developed a reliable, versatile and easy to maintain system to fit the economy and technology level of farmers for hill side range development. the proposed system featured a pair of sensors located analog the length of tractor. the output signals from the opto-counters operated by sensors, were led in to the central control unit. the final output signal, indicative of left-turn or right-turn command, was introduced to a hydraulic motor (actuator) by a solenoid valve. the actuator could then rotate the steering wheel shaft in the desired direction. The system was successfully tested on four different sites with average slope of 11-14% using a chiesel seeder, two bottom mounted moldboard plow, three bottom mounted moldboard plow and without hitching any elements behind the tractor. plots of the contour line height of each test track "y" versus the actual elevation of 14 equally spaced points analog each trce "x" produced the following reletionships: Y=1.009*-0.930 3 bottom mounted moldboard plow Y=1.000*-0.002 2 " " " " " " " Y=0.999*+0.011 chiesel seeder Y=0.999*+0.014 tractor with no implement indicating a reasonably acceptable performance.
ABSTRACT : The purpose of this investigation is to see the effects of changing diesel engines to diesel dual fuel engines (natural gas and gas oil) which posses one of the cheapest ways to solve the problems associated with diesel engines and to study the technology related to this type of engine in agricultural machinery such as tractors, combine harvesters and so on with gas oil combustion. this method also also has been compared with other methods such as making use of natural gas as a fuel source only, and advantages and disadvantages related to the economical and environmental effects has been considered. the experiment conducted in this regard showed that environmental concerns related to diesel engines could be reduced to an acceptable level. this technology requires full investigation specially in agricultural machinery which has been discussed in this article. keywords : Diesel Dual Fuel (DDF) Engine, Diesel Engine, Exhaust Emissions, Fuel Energy Consumption, Agriculture.
Bagher emadi (M,SC)
ABSTRACT : with 25.9 percent of the potato production, this crop is one of the most important in the Eastern Azarbaidjan especially Ardabil. after harvest, potatoes have to be kept for varying periods up to 6 month in orther to supply the national market throughout the year with potatoes for direct human consumption. The marketable quality of kept potatoes is greatly influenced by the keeping conditions. The storage losses and price fluctuation of potatoes are results of lacking suitable place for storage. The selection of suitable space for storage of potatoes proportionate order Ardabil is the aim of this. do, 1000 tons stores were chosen and method of building insulation was planned. The overall heat transfer coefficient was considered 0.4 and 0.25 w/m^2.k for walls and ceiling respectively. Also sandwich panels were selected in order to insulation material. In the other part of research, the cooling, heating and ventilation equipment factors was computed. To control the environmental conditions in the store, forced ventilation with outside air is applied. Due to climatically conditions in the Ardabil, ventilating rates of 129m^3 air/m^3 potatoes/hour is used for ventilation, cooling and heating of potatoes. so, axial-flow fans with a static pressure equal to 150 pa is used.
Summary: A new Discrete Element (DE) method has been developed to model the dynamic behaviour of an assembly of axi-symmetrically shaped fruits. In the new method, which we term the “multi-element” method, model fruits (taken here to also include vegetables, grains and nuts) are comprised of overlapping spheres whose centres are fixed in position relative to each other along the major axis of symmetry of the fruit. Element spheres are inscribed in the real fruit shape such that the diameter of the spheres varies with the fruit surface contour. Contact detection between two neighbouring model fruits is achieved using standard DE methods for two single spheres. The method thus takes advantage of the speed and accuracy of contact detection associated with standard DE schemes employing single spheres. The scheme is well suited to numerical modelling of post-harvest operations such as hopper filling and emptying, conveying, sorting and object manipulation where the produce are discrete entities with relatively round smooth surfaces. Keywords: Discrete Element Method, DEM, multi-element particles, dynamic behavior, fruits, simulation
Kazem kabiri ,( MS.C)
ABSTRACT : In this study the effect of different speeds and plowing depths on the performance of moldboard plow was evaluated. the soil was silty clay with 14%-16% moisture content. the performance parameters studied were draft, specific draft, drawbar power, and soil inversion. A randomized complete block design was used for statistical analysis of data. 9 treatments representing different levels of speed and plowing depth were replicated 3 times. it was found that draft, specific draft, and drawbar power, increased as the forward speed and plowing depth increased. it was also found that the increase of forward speed and depth of plowing improved the quality and quantity of soil inversion. since power requirement was directly proportional to the plowing depth, from economical standpoint, it is recommended that plowing depth should be determined on the basis of crop root requirement, for those crops with shallow roots a shallow may be sufficient.
Mojtaba ModaresRazavi ,( MSC )
ABSTRACT : The energy of wind has been in use for thousands of years. it has using for grinding grains and lifting water in eastern parts of Iran. it is said that vertical axis windmills have originally been invented by Iranians and are still in use in the original form and style as before at eastern borders of Iran such as Khaf, Birjand, etc. Unfortunately, this ancient technology which has been inherited from our ancestors is now unknown to most Iranians even to those who live in the region. some efforts should be made to introduce this ingenious device to all Iranians, specially young Iranian scholars so that to improve it's efficiency .
IN BRIEF... THE CONCLUSIONS INTRODUCTION: PROJECT
PROCEDURE: TABLE 1.
Seed
Viability.
This project solely tested for seed damage and does not imply PAMI analysis of other factors of performance. RESULTS AND DISCUSSION: TABLE 2. Results With "New" Distribution System.
TABLE 3. Results
With "Old" Distribution
System.
* The negative value of seed damage was not considered accurate, It was likely measured because the amount of damage due to the air seeder was very small relative to variation of viable seed in the sample.Statistical analysis conducted on each of the tests indicated that the amount of damage was not significant. Thus, the specific measured values have little relevance. The primary result of these tests is that the Bourgault Air Seeder did not cause any significant damage to pulse seeds at the manufacturer's recommended settings.The previous pulse crop damage report on air seeder components had implied some unfounded concerns with certain components used by Bourgault; specifically metering systems that use augers and primary/secondary manifold systems. Although no specific Bourgault components were used in that test, the principles of operation were similar. However, this project on the Bourgault machine has confirmed that none of the components will cause pulse seed damage when operated at the proper fan speed settings, as recommended by the manufacturer. General Tips for Producers Seeding Pulse
Crops With Air Seeders: This information is maintained by Alberta Farm Machinery Research. |
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