Mehran University Research Journal of Engineering and Technology

5

Authors: Memon Z.A., Shah S.A., Jumani M.S.

Two different engine models, parametric engine model and engine map model are employed to analyze the dynamics of an engine during the gear shifting. The models are analyzed under critical transitional manoeuvres to investigate their appropriateness for vehicle longitudinal dynamics. The simulation results for both models have been compared. The results show the engine map model matches well with the parametric model and can be used for the vehicle longitudinal dynamics model. The proposed approach can be useful for the selection of the appropriate vehicle for the given application

6

Authors: Sahito A.R., Mahar R.B., Chandio F.A.

Assessment of kinetic of AD (Anaerobic Digestion) is a beneficial practice to forecast the performance of the process. It is helpful in the design of AD vessels, substrate feeding and digestate exit systems. The aim of this work was to assess the kinetics of anaerobically digested buffalo dung at different quantities of water added. It comprises the assessment of the specific methane production on the basis of VS (Volatile Solids) added in each reactor by using three first order models, i.e. the modified Gompertz model, the Cone model and the Exponential Curve Factor model. The analysis was tested by using the three statistical parameters, i.e. the coefficient of multiple determinations, the standard deviation of residuals and the Akaike?s Information Criteria. The result reveals that the Exponential Curve Factor model was the best model that described the experimental data well. Moreover, there was not a direct or indirect relation between the kinetic coefficients of the AD process with the varying total or volatile solid content

7

Authors: Siyal A.A., Siyal A.G., Mahar R.B.

Pre-harvest reliable and timely yield forecast and area estimates of cropped area is vital to planners and policy makers for making important and timely decisions with respect to food security in a country. The present study was conducted to estimate the wheat cropped area and crop yield in Hyderabad District, Pakistan from the Landsat 8 satellite imagery for Rabi 2013-14 and ground trothing. The required imagery of district Hyderabad was acquired from GLOVIS and was classified with maximum likelihood algorithm using ArcGIS 10.1. The classified image revealed that in district Hyderabad wheat covered 10,210 hectares (9.74% of total area) during Rabi season 2013-14 against 15,000 hectares (14.3% of total area) reported by Crop reporting Services (CRS), Sindh which is 30% less than that of reported by CRS. A positive linear relation between the wheat crop yield and the peak NDVI with coefficient of determination R2 = 0.91 was observed. Crop area and yield forecast through remote sensing is easy, cost effective, quick and reliable hence this technology needs to be introduced and propagated in the concerned government departments of Pakistan

8

Authors: Burdi M.K., Uqaili M.A., Memon M.R.

A detailed investigation of the universal motor is developed and used for various dynamic steady state and transient operating conditions of loads. In the investigation, output torque, motor speed, input current, input/output power and efficiency are computed, compared and analyzed for different loads. While this paper discusses the steady-state behavior of the universal motor, another companion paper, ?Transient dynamic behavior of universal motor?, will discuss its transient behavior in detail. A non-linear generalized electric machine model of the motor is considered for the analysis. This study was essential to investigate effect of output load on input current, power, speed and efficiency of the motor during operations. Previously such investigation is not known

9

Authors: Ashraf A., Mustafa N., Iqbal M.B.

Rod-kohi system of irrigation is often generally referred to as flood irrigation or spate irrigation system in which floods of the hill torrents are diverted into plain area for irrigation purpose. In rod-kohi region where uncertainty exists in flood water availability for irrigation use, groundwater is a valuable resource used mainly as supplement source of irrigation. The region, being rich in natural resources, is remained far behind in terms of data availability and data quality, the situation that has affected incredibly the needs of future planning and development. In the present study, major landuse/landcover classes of the region were identified and delineated using Landsat ETM+ (Enhanced Thematic Mapper Plus) image data and related with groundwater potential for interactive analysis in GIS (Geographic Information System). The potential groundwater zones were delineated and assessed on the basis of aquifer characteristics in the region. Rangeland and exposed rocks were identified over 70% of the rod-kohi region i.e. total area about 42 Mha (Million hectares). Share of cropped area and bare soil or culturable waste was about 3.5 and 15.4%, respectively. High and medium potential of groundwater were estimated in about 2.3 Mha out of which 60% exist under bare soil, 16% under cropped area and the rest underneath other landuse classes. High efficiency irrigation techniques like drip and rain-gun system need to be adopted in areas having substantial groundwater potential in order to sustain agriculture production. The study would provide base for detail investigation

10

Authors: Syed A.A., Soomro A.M., Khizer A.N.

The autonomous manipulation of the medical robotics is needed to draw up a complete surgical plan in development. The autonomy of the robot comes from the fact that once the plan is drawn up off-line, it is the servo loops, and only these, that control the actions of the robot online, based on instantaneous control signals and measurements provided by the vision or force sensors. Using only these autonomous techniques in medical and surgical robotics remain relatively limited for two main reasons: Predicting complexity of the gestures, and human Safety. Therefore, Modern research in haptic force feedback in medical robotics is aimed to develop medical robots capable of performing remotely, what a surgeon does by himself. These medical robots are supposed to work exactly in the manner that a surgeon does in daily routine. In this paper the master slave tele-robotic system is designed and implemented with accuracy and stability by using 6DOF (Six Degree of Freedom) haptic force feedback devices. The master slave control strategy, haptic devices integration, application software designing using Visual C++ and experimental setup are considered. Finally, results are presented the stability, accuracy and repeatability of the system