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Western Canada has large acreage of oilseed flax, but unfortunately a small percentage of total crop residue (flax straw) produced annually is being commercially used. Therefore, farmers are still burning the flax straw. Flax fiber and straw has highest strength amongst the different natural fibers, therefore, the prospect of using them as biorenewable reinforcement in recycled/ virgin polymer matrices has gained attention in recent years. Flax strawboard has a potential to replace the currently used wood and other crop like wheat/barley straw boards for different industrial application. In this research Oilseed flax straw reinforced composite boards were developed using flax shives with biopolymer binder made out of recycled/ pure thermo plastic and flax fiber. Some advantages of such materials are high strength, low density, good insulation capacity against heat and moisture transfer, and biodegradability.

Flax, which is known for its linens and oils that are used for industrial products, can also be utilized as a cost effective and environmentally acceptable approach to the creation of a partially biodegradable biocomposite. Biocomposite material is investigated by combining recycled tire rubber, flax and linear low density polyethylene (LLDPE). The manufacturing process which be used to fabricate the biocomposite product included Extrusion and Compression Molding. Optimizing and studying the composition percentages of the compounds were studied in this paper. Moreover, the properties of the product were observed by using tensile test, tearing test, water absorption test, hardness test and Differential Scanning Calorimetry.

This work is based on comparative study of oilseed flax fibre and glass fibre reinforced composite boards for potential application in automotive industries. The material characterizations of flax and glass fibre-composites using unsaturated polyester as matrix were evaluated. Vacuum infusion was used for fabrication of composites. Flexural, tensile, water absorption and color tests were conducted on the composite boards. The density and the moisture content of flax/glass fibre mats were also measured. Three types of composite boards, including flax, glass and flax-glass sandwich were developed and characterized.

A hydrostatic actuation system referred to as the Electro Hydraulic Actuator (EHA) has been designed and prototyped. In this paper, a mathematical model of the EHA is reviewed and analyzed. This theoretical analysis is supported by open-loop experimental results that indicate the presence of nonlinearities but at a degree that is considerably less than that of conventional hydraulic systems with servo-valves. The behavior of the system can be approximated as piece-wise linear with the damping ratio and natural frequency changing according to a piece-wise operating region. The EHA model is used in conjunction with experimentation and numerical optimization for quantifying the influence of unknown parameters in this system. A parametric model for the EHA is subsequently proposed and validated.

This paper compares the characteristics of a high-precision hydrostatic actuator to that of conventional hydraulic systems using servovalves. Servovalve controlled hydraulic actuators retain their market share as they provide precision movement and offer a very high torque to mass ratio at the final actuation point. The input current/output torque relationship of a conventional hydraulic actuation system is reviewed in a robotic context. This relationship is summarized by a mathematical model that can be expressed in a generalized form. This model is used for the analysis of flow and dynamic characteristics. The design and modeling of a recently proposed high-performance hydrostatic actuation system referred to as the ElectroHydraulic Actuator (EHA) is briefly reviewed. A prototype of this actuator has been produced and has demonstrated a comparable performance to servovalve controlled conventional hydraulic systems.

A new prototype of a single unit till-planting system suitable for Egyptian soil was designed, constructed, and tested under soil bin and field conditions. Measurements were taken for draft, soil mean weight diameter, and seedling emergence. Results indicated that there are potential benefits of using this system rather to other tillage systems under dry and hard soil conditions. An optimum seedbed was created for rapid seedling emergence. Combinations of tillage, planting, and fertilizer application were performed in a single operation to reduce power and time requirements for crop production.

Pulse width modulation (PWM) has been used to alter the performance of on-off hydraulic control valves to make them perform as proportional type flow control valves. Nonlinear performance resulting from time delays in valve switching as well as valve wear due to continuous cycling continue to persist as operational problems. This paper examines a new technique called modified PWM control. The method was found to provide accurate control with a minimum of valve chatter.

The performance of simple tool shapes in terms of draft with speed of operation was evaluated in the soil bin facility of the Department of Agricultural and Bioresource Engineering, University of Saskatchewan. A hydraulic driven monorail system was developed, which was capable of speeds up to 10 m/s. The results showed that the disturbed soil remained close to the cutting path, and the elliptical shape exhibited the lowest draft increment with speed.

In order to use computer to carry out quick, accurate and economic design of product shape and colour, a package of AUTOLISP programs was developed which can be run under AUTOCAD main environment. Due to the limitation of AUTOCAD 11.0 and 12.0 in 3-D design of complex curved surface, the 3-D design functions were enhanced in the following aspects: (1) 3-D line JOIN and BREAK commands were developed to join and break 3-D polylines. SPIRAL command was designed to create 3-D cone or cylindrical spiral line. In addition, EFTURN and MEFTURN commands were developed to change the vertex sequence of polyline totally or midway. (2) 3-D elements and characters Existing subroutines were revised to directly generate Box, Cone, Pyramid, Dome or Dish, Torus, Sphere and Wedge ready for solid modeling. Furthermore, CONVEX, HOLE and TUBE commands were developed to generate different kinds of convex, hole and tube respectively.

Variable rate nitrogen fertilization (VRNF) is a technique being developed for agricultural applications in recent years. In designing a controller for VRNF system, it is hoped that the process parameters, which are difficult to measure, could be identified on-line so that the model-based digital controllers or adaptive controllers could be used to achieve better system performance. In this paper, the problems associated with the on-line process parameter identification for the control of variable rate nitrogen fertilization are analyzed. Simulation studies and experimental tests were conducted to determine a suitable parameter estimation algorithm and the influence of pseudo random binary signal and external torque disturbance on the parameter identification accuracy. The results from the simulation and experimental studies revealed that the recursive least square algorithm is most suitable for parameter estimation.

The agricultural combine harvester is one of the most complex of machines used in cereal grain production. It is believed that significant increases in efficiency and productivity could be realized if several of the machine adjustments could be automatically controlled. One of the most important parameters to measure and control is the feedrate, i.e. the mass flow rate of material entering the machine. This paper reports on an investigation of a sensor, using electrical capacitance techniques, to measure feedrate.

Understanding the Relationships between plants and soil is important in the development of methods of crop production. Although physical properties of soil conducive to plant growth can be recognized by experienced observers, many of these properties have not been defined satisfactorily in mathematical or physical terms. A method of measuring penetration resistance and energy exerted by a mechanical seedling (a steel probe simulating a seedling) as it moved upward through the soil surface under different levels of surface compaction and soil moisture was examined. Mechanical seedlings with 2.06, 3.19 and 4.65 mm tip diameters were tested at soil moisture levels of 13, 17, and 20%. The penetration rate of the mechanical seedling while moving through the soil was held constant at 10 mm/min. Results showed that the emergence energy increased directly with soil surface compaction pressure, initial soil moisture content, and mechanical seedling diameters.