Mehran University Research Journal of Engineering and Technology

7

Authors: Qureshi A., Marvi M., Umrani F.A.

CoM (Center of Mass) of earth is a very important factor which can play a major role in satellite communication and related earth sciences. The CoM of earth is assumed to be around equator due to geometrical shape of earth. However, no technical method is available in the literature which can justify the presence of CoM of earth around equator. Therefore, in this research work the CoM of earth has been located theoretically with the help of mathematical relations. It also presents the mathematical justification against the assumption that equator is the CoM of earth. The effect of calculated CoM of earth on geostationary satellites has also been discussed. The CoM of earth has been found mathematically by using land to ocean ratios and the data is collected from the Google earth software. The final results are accurate with an approximate error of 1%.

8

Authors: Gohar K., Mirza J., Ali M.K.

Consumer preferences can lay foundation for determining key product attributes essential for the success of a product in the market, enabling the manufacturers optimally allocate resources towards imparting these critical attributes. However identification of consumer preferences especially for new products is a challenging task. This research investigated the consumer preference factors for solar home systems in Rawalpindi/Islamabad (Pakistan); applying MCDM (Multi Criteria Decision Making) approach, AHP (Analytical Hierarchy Process) survey and analysis method is used for prioritization of the factors and comparison of decision alternatives. Fourteen factors grouped into five categories are selected. It has been found that the manufacturers have to emphasize on performance and functional attributes of these systems at this stage, the cost factors are comparatively lower in importance. Make and warranty, Environmental and Physical features are also lesser important to the early adopters

9

Authors: Shaikh S.A., Jumani M.S., Hussain T.

Assembly line operations generally involve physical and cognitive demanding tasks. Simultaneous performance under physical and cognitive demanding tasks may create physical and mental stresses. A within subjects study was carried out to determine the effects of assembly levels (variable assembly and consistent assembly) on working conditions. Nine participants participated in a study and performed 8 conditions. The objective of the study was to determine the relation between physical and cognitive demands in a simulated task involving simultaneous performance of physical (fastening nuts and bolts) and cognitive (code matching with secondary task of memorizing the code) demanding task. Results showed the significant effects of assembly order (consisted of the concurrent performance of physically and cognitively demanding task) on the working conditions. Quality of performance was affected by variable assembly order, high mental demand and above shoulder height.

5

Authors: Ali T.H., Khahro S.H., Memon F.A.

It has been observed that the construction industry is one of the notorious industry having higher rate of fatilities and injuries. Resulting in higher financial losses and work hour losses, which are normally faced by this industry due to occuaptional accidents. Construction industry has the highest occupational accidents rate recorded throughout the world after agriculture industry. The construction work site is often a busy place having an incredibly high account of activities taking place, where everyone is moving in frenzy having particular task assigned. In such an environment, occupational accidents do occur. This paper gives information about different types of occupational accidents & their causes in the construction industry of Pakistan. A survey has been carried out to identify the types of occupational accidents often occur at construction site. The impact of each occupational accident has also been identified. The input from the different stakeholders invloved on the work site was analyzed using RIW (Relative Importance Weight) method. The findings of this research show that ?fall from elevation, electrocution from building power and snake bite? are the frequent occupational accidents occur within the work site where as ?fall from elevation, struck by, snake bite and electrocution from faulty tool? are the occupational accident with high impact within the construction industry of Pakistan. The results also shows the final ranking of the accidents based on higher frequency and higher impact. Poor Management, Human Element and Poor Site Condition are found as the root causes leading to such occupational accidents. Hence, this paper

6

Authors: Syed U., Jhatial R.A., Marri H.B.

Polyester fabric is generally dyed using high temperature dyeing technique and carrier. Both techniques require high energy consumption while few carriers are toxic in nature. In this study, 100% polyester woven fabric was dyed by microwave and conventional dyeing technique with disperse dye; Foron Blue RD GLN by an exhaust method for short dyeing cycle (15 and 30 min). The fabric samples were dyed using conventional high temperature dyeing technique using recommended recipe. Moreover, samples were also dyed using microwave technique with recommended recipe and by the addition of salt and urea, pre-treatment with caustic and organic solvent for improving the dye uptake value and fastness properties. The dyeing assessment; (K/S)?max value by Datacolor spectrophotometer, dye uniformity by optical microscope and washing fastness by grey scale were measured. It has been observed that over conventional dyeing method, microwave irradiation dyed sample gives almost 70% high (K/S)?max value and uniform dye penetration and good to very good washing fastness property. In addition, microwave dyeing gives excellent dyeing behavior at short dyeing cycle; 15 min; hence saves energy and sustainable dyeing process.

7

Authors: Baloch J.A., Khanzada T.J.S., Memon S.

The advancement in technology has made it possible to create small in size, low cost sensor nodes. However, the small size and low cost of such nodes comesat at price that is, reduced processing power, low memory and significantly small battery energy storage. WSNs (Wireless Sensor Networks) are inherently ad hoc in nature and are assumed to work in the toughest terrain. The network lifetime plays a pivotal role in a wireless sensor network. A long network lifetime, could be achieved by either making significant changes in these low cost devices, which is not a feasible solution or by improving the means of communication throughout the network. The communication in such networks could be improved by employing energy efficient routing protocols, to route the data throughout the network. In this paper the SVR (Spatial Vector Routing) protocol is compared against the most common WSN routing protocols, and from the results it could be inferred that the SVR protocol out performs its counterparts. The protocol provides an energy efficient means of communication in the network

7

Authors: Sahito A.A., Halepoto I.A., Tunio S.M.

Electricity sector of Pakistan is facing daunting energy crisis. Generation deficit results in long duration of load shedding throughout the country. Old aged distribution system, lack of maintenance and equipment failure cause long unplanned outages and frequent supply interruptions. HESCO (Hyderabad Electric Supply Company) is facing high technical losses, supply interruption and financial loss due to transformer damages. Infrared Thermography is non-contact, safe and fast measure for distribution system inspection. In this paper, thermographic inspection for different distribution system equipment is carried out to identify possible developed faults. It is observed that IR (Infrared) thermography is effective measure for detecting developed faulty conditions at the initial stages to avoid unplanned outages

8

Authors: Ali S., Ghani U., Latif A.

This paper presents results from an experimental study which was conducted at Technical University Delft, Netherland. The research was made on obstructions resembling weirs in an open channel. This weir-type obstruction was a representative of groyne/dike in a natural channel. The experimentation was performed in the laboratory for different values of inflow (25 l/sec and 40 l/sec), weir with and without vegetation and with different leeward slopes of the weir (1:4 and 1:7). The results were obtained for Reynolds normal stresses, longitudinal and vertical velocities. A comparison was made between the results of 1:4 and 1:7 leeward slope ratios. The data was collected with a LDA (Laser Doppler Anemometer). The vegetation was modeled with vertical circular rods placed over the crest of the weir. The blockage area due to this vegetation was 25% of the total area. The velocity data was gathered at around ten locations both at upstream and downstream the weir to get an insight into the flow structure. The results have been presented in the shape of vertical profiles both for velocities as well as Reynolds stresses at different locations of the channel.

6

Authors: Kiyani M.K., Loan A.

Channel impairments effects are evaluated by inclusion of phase noise in a synchronization error correction algorithm for MIMO (Multiple Input Multiple Output) OFDM (Orthogonal Frequency Division Multiplexing) systems. The original synchronization error correction algorithm applicable to AWGN (Additive White Gaussian Noise) channel pertaining to SISO (Single Input Single Output) system is modified in the presence of SUI (Stanford University Interim) channel models and then applied to MIMO systems. Then the performance of this modified algorithm is verified through simulations under the effects of channel impairments

8

Authors: Siddiqui I., Soomro A.A., Ajmal S.

The CT (Computed Tomography) is a non-destructive technique that can provide information of internal structure of coal in two-dimensional, this technology is now widely used in geoscientific research. This technique is used for the measuring cleat dimension and pore width of the Thar coal. The slicing study of Thar coal shows that the length of cleats in various seams ranges from 0.5-5mm and the aperture of these cleats vary between 0.1-0.5mm. The porosity also plays an important role in storage and production of coalbed methane, the size or width of pores in coal under investigation ranges between 0.1-0.7mm. The present investigation shows that Seam-III and V of the can be considered as viable as hold a potential for CBM (Coalbed Methane) resources, however, the coal samples from these seams need to be analyzed for the presence of methane In Thar coalfield, the pore volume ranges from 0.06-2.36 cc/g and pore diameter in Thar coal ranges from meso-pore and macro-pore (34.81-121.51Å). These meso and macro-pores serve as transport pathways, and little methane is stored in these pores in the adsorbed state.

8

Authors: Kumar W., Qadeer S.

This paper presents the performance analysis of a finite capacity energy efficient femtocell network. A FAP (Femtocell Access Point) provides continuous connectivity for M communicating nodes in this network. The data transmission from M communicating nodes to the central entity (FAP) is represented using M/M/1/K queue. To save energy, the server, in this case, takes exponentially distributed vacations during idle periods. Due to finite buffer size of FAP, this network represents a finite capacity system. The network model where sever takes vacation to save energy is solved with help of MGM (Matrix Geometric Method). For different system capacities, the network performance is analyzed in terms of power savings and QoS (Quality of Service) parameters such as utilization, average packet delay, and packet blocking probability. Results show that with small traffic intensity the energy savings is high, whereas utilization, delay and blocking are low. Moreover, the maximum energy can be saved when system in quite underutilized

10

Authors: Arif M., Shaikh A.A., Qureshi I.A.

In ultrasound harmonic imaging, high bandwidth is essential to provide good axial resolution at the receiver. However, increasing the bandwidth will cause overlapping amongst the nonlinear harmonic components. Conventional frequency domain filtering approach normally fails to extract the desired harmonic component under overlapped harmonic condition. The purpose of this work is to use broadband linear chirp signals for better SNR (Signal to Noise Ratio) andaxial resolution. Also on the receiving side, the FrFT (Fractional Fourier Transform) is used as a filtering tool to extract the overlapped second harmonic component from the nonlinear received signal. Pulse compression of the second harmonic chirp signal is also performed using the harmonic matched filter to restore axial resolution. Comparing the results of FrFT pre-filtered with unfiltered compressed signals; it is found that up to a 35.5dB RSLL (Reduction in Range Side Lobe Level) is realisable leading to an improved detection and image resolution

12

Authors: Ghani U., Ali S., Arif S.

The velocity profiles in open channel flows start developing after entering into the channel for quite some length. All types of laboratory experiments for open channel flows are carried out in the fully developed flow regions which exist at some length downstream the inlet. In this research work an attempt has been made to investigate the impact of roughness and slope of the channel bed on the length required for establishment of fully developed flow in an open channel. A range of different roughness values along with various slopes were considered for this purpose. It was observed that an increase in roughness results in reduction of development length; and development length reduces drastically when roughness reaches to the range normally encountered in open channel flows with emergent vegetation or natural river flows. However, it was observed that the change of slope did not have any noticeable effect on development length. This work suggests that CFD (Computational Fluid Dynamics) technique can be used for getting a reliable development length before performing an experimental work

12

Authors: Halepoto I.A., Uqaili M.A., Chowdhry B.S.

Nowadays, due to power crisis, electricity demand forecasting is deemed an important area for socioeconomic development and proper anticipation of the load forecasting is considered essential step towards efficient power system operation, scheduling and planning. In this paper, we present STLF (Short Term Load Forecasting) using multiple regression techniques (i.e. linear, multiple linear, quadratic and exponential) by considering hour by hour load model based on specific targeted day approach with temperature variant parameter. The proposed work forecasts the future load demand correlation with linear and non-linear parameters (i.e. considering temperature in our case) through different regression approaches. The overall load forecasting error is 2.98% which is very much acceptable. From proposed regression techniques, Quadratic Regression technique performs better compared to than other techniques because it can optimally fit broad range of functions and data sets. The work proposed in this paper, will pave a path to effectively forecast the specific day load with multiple variance factors in a way that optimal accuracy can be maintained

8

Authors: Waseer T.A., Halepoto I.A., Joyo M.A.

In this work we have designed, modeled and simulated a 32-channel DWDM (Dense Wavelength Division Multiplexing) system using OptiSystem photonic simulator. The system is tested for external transmitter with NRZ (Non-Return Zero) encoder using Mech-Zehnder modulator, which accepts input from CW (Continuous Wave) laser array and low pass Bessel filter that supports PIN photodiode at receiver end. System performance for optical channels has been compared by varying channel length of EDFA (Erbium Doped Fiber Amplifier) and Raman amplifiers to identify its impact in the sense of eye diagram, QF (Quality Factor) and minimum BER (Bit Error Rate). Experimental setup was done by varying channel lengths of 60, 100, 120, 150 and 170Kms. It was found that EDFA has better performance in the sub-low ranges of 60Kms, whereas Raman offers better performance at wider channel lengths i.e. more than 100Kms. The proposed work can be extend for the avoidance of amplifier utilization at wider ranged.

8

Authors: Shah M.S., Wagan A.I., Unar M.A.

Recent years have seen an increasing interest in the design of AQM (Active Queue Management) controllers. The purpose of these controllers is to manage the network congestion under varying loads, link delays and bandwidth. In this paper, a new AQM controller is proposed which is trained by using the SVM (Support Vector Machine) with the RBF (Radial Basis Function) kernal. The proposed controller is called the support vector based AQM (SAM) controller. The performance of the proposed controller has been compared with three conventional AQM controllers, namely the Random Early Detection, Blue and Proportional Plus Integral Controller. The preliminary simulation studies show that the performance of the proposed controller is comparable to the conventional controllers. However, the proposed controller is more efficient in controlling the queue size than the conventional controllers

8

Authors: Kumar W., Aamir S., Qadeer S.

A feasible solution to wireless spectrum scarcity is the deployment of femtocells along with already existing or new macrocells. This hybrid architecture not only helps to increase the system capacity but also improves the wireless signal quality for indoor users. Moreover, these femtocells can offer higher data rates to indoor users. In this paper, we analyze the performance of a finite capacity femtocell network. The transmission of data from Mcommunicating nodes to a FAP (Femtocell Access Point) is modelled as M/M/1/K queue. The access point in this case can hold a maximum of K-1packets in its buffer, hence the system represents a finite capacity network. The performance of the system is evaluated in term of QoS (Quality of Service) parameters such as packet blocking probability, average packet delay and utilization for different buffer sizes. The results reveal that with an increase in buffer size, the packet blocking probability decreases however at the cost of increased average delay

10

Authors: Luhur M.R., Peinke J., Waechter M.

This contribution provides the development of a stochastic lift and drag model for an airfoil FX 79-W-151A under unsteady wind inflow based on wind tunnel measurements. Here we present the integration of the stochastic model into a well-known standard BEM (Blade Element Momentum) model to obtain the corresponding aerodynamic forces on a rotating blade element. The stochastic model is integrated as an alternative to static tabulated data used by classical BEM. The results show that in comparison to classical BEM, the BEM with stochastic approach additionally reflects the local force dynamics and therefore provides more information on aerodynamic forces that can be used by wind turbine simulation codes

10

Authors: Shaikh F.K., Ansari A.Q., Mahoto N.A.

Mobility in WSNs (Wireless Sensor Networks) introduces significant challenges which do not arise in static WSNs. Reliable data transport is an important aspect of attaining consistency and QoS (Quality of Service) in several applications of MWSNs (Mobile Wireless Sensor Networks). It is important to understand how each of the wireless sensor networking characteristics such as duty cycling, collisions, contention and mobility affects the reliability of data transfer. If reliability is not managed well, the MWSN can suffer from overheads which reduce its applicability in the real world. In this paper, reliability assessment is being studied by deploying MWSN in different indoor and outdoor scenarios with various duty cycles of the motes and speeds of the mobile mote. Results show that the reliability is greatly affected by the duty cycled motes and the mobility using inherent broadcast mechanisms.

12

Authors: Hayat M.F., Holynski T., Afzal M.

In this paper, we present a performance study of OBS (Optical Burst Switched) combined node via mixed loss delay queueing models. In an OBS network, a node combining both edge and core switching functions multiplex the local traffic with the transit traffic on the output wavelengths channels. To control the channel sharing, strategies are proposed and analyzed in this study by extending the basic mixed loss delay queueing models. The presented models are solved by Markov chain techniques and the results are compared, and where necessary also supported, by the simulations of an OBS node implemented in detail

16

Authors: Mahoto N.A., Shaikh F.K., Ansari A.Q.

Healthcare service centres equipped with electronic health systems have improved their resources as well as treatment processes. The dynamic nature of healthcare data of each individual makes it complex and difficult for physicians to manually mediate them; therefore, automatic techniques are essential to manage the quality and standardization of treatment procedures. Exploratory data analysis, patternanalysis and grouping of data is managed using clustering techniques, which work as an unsupervised classification. A number of healthcare applications are developed that use several data mining techniques for classification, clustering and extracting useful information from healthcare data. The challenging issue in this domain is to select adequate data mining algorithm for optimal results. This paper exploits three different clustering algorithms: DBSCAN (Density-Based Clustering), agglomerative hierarchical and k-means in real transactional healthcare data of diabetic patients (taken as case study) to analyse their performance in large and dispersed healthcare data. The best solution of cluster sets among the exploited algorithms is evaluated using clustering quality indexes and is selected to identify the possible subgroups of patients having similar treatment patterns