Mechanical Engineering

A second order process of 164.5 seconds settling time is controlled using a PDF controller (through simulation). The controller is tuned by minimizing the sum of square of error of the control system using MATLAB. Functional constraints are imposed on the maximum percentage overshoot, settling time and stability condition. The result was reforming the process slow response and producing a closed-loop control systems of a maximum percentage overshoot less than 2 % and a settling time less than 0.6. The performance of the tuned-PDF controlled process is compared with that tuned using the ITAE standard forms.

Uncertainty of measurement has attracted more researchers in recent past. In this paper ,an attempt is made to review the status of literature in measurement uncertainty. The uncertainty of measurement is related to measurement and calibration process only. A very few literature are available related to uncertainty of measurement. A literature classification scheme is suggested. A number of articles from referred international journals and international conferences are classified based on various methodology (GUM, analytical approach and Monte-Carlo approach etc). The paper shows the country wise awareness in the field of uncertainty. The gap in the research are identified along with the scope of UOM in various application.

The experiment was conducted at the fields of Agriculture College-University of Baghdad Al- Jadiriyah in 2015 in sandy loam soil to evaluate using locally Ultrasonic device for determining the tillage appearance for different primary tillage equipment. New Holland" tractor was used in this study. Two levels of soil moisture included 18-20% and 14-16% and primary tillage implements included: disc plow , chisel plow and sweep plow were used . Soil surface roughness, number of clods with diameter larger than 10 cm , disturbed soil volume, bulk density, total porosity were measured. Split plot design under randomized complete block design (RCBD) with three replicates was used. The results were showed that the best soil surface roughness was obtained at the second moisture level, and higher porosity 53.89 % at the first moisture level and there were no significant differences for levels moisture in both the number of clods with diameter larger than 10cm , disturbed soil volume and bulk density. Sweep plow superior in obtained less soil surface roughness , less number of clods with diameter large than 10cm 10.00 clod / m2 and higher porosity 53.94 % compared with chisel plow and disc plow. Higher disturbed soil volume obtained at the chisel plow 1193.00 m3 / hr, while no significant differences in bulk density attributed by plows types. Sweep plow with second moisture level was the superior in obtained less soil surface roughness and less number of clods with diameter large than 10cm 9.33 clod / m2, and sweep plow with first moisture level obtained less bulk density 1.17 mg / cm3 , higher porosity 55.33% While higher disturbed soil volume 1202.00 m3 / hr. obtained in chisel plow with first moisture level treatment

Overheating is the major problem ofhermetic compressor due to extra amount of heat added from the motor windings to the shell. It reduces the mass flow rate of the system which results in reduced compressor volumetric efficiency and extremely high discharge temperature. The refrigerant injection is a technique to improve the system performance. This paper reviews the major research on refrigerant injection techniques in detail. The refrigerant injection technique divided into two categories, first is vapor injection and another is liquid injection. Flash tank and internal heat exchanger are two cycles for refrigerant injection. These two cycles are discussed in detail.

Deep-sea mining system technology is complex, expensive and difficult to develop due to high cost and risks of physical models constructions. The development of deep-sea mining simulation test system is the early concept of design innovation and it is an effective tool to accelerate the maturity of the technology to ensure stable and reliable performance. RecurDyn is fully integrated linear and non-linear FEA capability software which allows the creation of detailed realistic models for design studies and product's performance improvement. In this paper a miner track system was modeled based on an optimized design in order to check for its feasibility.

A numerical investigation of the vortex shedding past a circular cylinder in a two- dimensional channel of varying height is presented in the term of Strouhal number by solving continuity and momentum equations using FLUENT 6.3. The computational grid structure is generated by using Gambit. In this work, the result is carried out with blockage ratio b=0.83, 0.85, 0.88.

This paper is a review on Warranty analysis, it basically explain about how warranty cost is important to handle carefully by all element of organization. Warranty cost needs uniformity to analyze throughout its user. Warranty cost analysis is challenging procedure as data become complicated when it consider different real life situations. Warranty claims are also part of effective warranty analysis. Different models explained by researches discussed to understand warranty analysis aspect. It studied different model for warranty analysis.

Damping is the material's ability to dissipate elastic strain energy during cyclic loading. Materials with high damping capacity are significant in the present day scenario for transportation and other industrial applications. The development of materials with high damping capacity is one of the efficient measures to reduce vibrations, thereby noise. Low weight materials like aluminum and magnesium have excellent mechanical properties, but poor in damping.