Mehran University Research Journal of Engineering and Technology

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.