Open Access Original Research Article

Performance of Isolated Footings Reinforced Randomly by Glass Fiber

Elsayed El Kasaby, Mohammad Farouk A. Bdelmagied

Journal of Engineering Research and Reports, Page 1-8
DOI: 10.9734/jerr/2019/v6i116935

Fiber glass reinforced concrete (FGRC) is used form any structural elements due to its high mechanical properties, particularly flexural strength. As the concrete crack forming process accelerates and the probability of sudden fractures increases. There were various methods to eliminate this weakness of concrete. One of most common methods was employed of randomly distributed fiber. In this paper, two types of isolated footings were utilized, square and rectangular shape reinforced by a fiber glass with a length of 18 mm and having a rate of (0.20, 0.30, 0.35, 0.40, 0.50 and 1.00%) of weight, to experimentally investigate the tensile and fatigue properties of footings The results of FGRC were compared with the reinforced steel concrete. The results revealed that FGRC has a positive effect on the tensile and fatigue properties of isolated footing, especially with higher percentage of used fiber glass.

Open Access Original Research Article

A Study of Vacuum Efficiency for Silicon on Insulator Wafers

Bryan Christian S. Bacquian, Frederick Ray I. Gomez

Journal of Engineering Research and Reports, Page 1-6
DOI: 10.9734/jerr/2019/v6i116936

The development on thinner packages has become the trend and focus in semiconductor packaging industry. The necessity of thinner packages also entails a thinner vertical structure of the integrated circuit (IC) design. As a major contributor on the vertical structure of the IC package, die or wafer is also essential to go thinner. As the wafer goes thinner, various problems may occur during transport and even the back grinding process, itself.

Wafer warpage is one of the main concerns during the process. The effect of proper vacuuming will play major role in processing SOI wafers. Insufficient vacuum may cause non-planar wafer in contact with the chuck table that may result to poorer grinding and worst broken wafer. 

Different silicon wafer technology has been released to cater different functionality on different industry markets. One popular silicon technology is Silicon On Insulator (SOI) technology. SOI wafers have a step type passivation wherein the edge of the wafer is observed to have 30um thinner than its center. The stepping effect also contributes to the 0.5mm wafer warpage prior back grinding. Evaluating the effect of vacuum efficiency to eliminate such warpage is discussed on this technical paper.

Open Access Original Research Article

Effectiveness of Various Techniques Using FRP for the Strengthening of R. C. Beams with Tension Lap Splices

Mohamed H. Makhlouf

Journal of Engineering Research and Reports, Page 1-18
DOI: 10.9734/jerr/2019/v6i116937

This paper presents an experimental program conducted to investigate the flexural performance of RC beams with tension reinforcement lap splice strengthened using externally bonded FRP different techniques in splice region. The specimens were reinforced on the tension side with four deformed bars spliced at mid span. The tested beams are of 3200 mm total length and 250*120 mm cross section, tested in positive bending. The considered parameters were splice length, type of FRP (glass or carbon), strengthening techniques in splice region (externally confine strips around cross section, Near Surface Mounted technique "NSM" stirrups, externally bonded sheets or bars on the tension face, number of GFRP strips layers (one layer, two layers, and three layers), and shape of NSM stirrups (Box or U shape). No additional anchorage mechanism or bonding methodology was applied for the FRP strips on the concrete except the epoxy adhesive. The effect of these factors on the failure of modes, the ultimate load, the bond strength and that the ductility were investigated. The results indicated that all applied strengthening techniques were efficient in improving the bond strength of the lap splices, the ductility, and the load-deflection behavior of the tested beams, especially when strips were installed over the splice region. This study approved that NSM technique gave more prominent simplicity of employ.

Open Access Original Research Article

Adsorption of Cyanide from Cassava Wastewater Using Calcined and Activated Oyster Shell Ash

Oto-Obong P. Akpan, B. R. Etuk

Journal of Engineering Research and Reports, Page 1-9
DOI: 10.9734/jerr/2019/v6i116938

Calcined ash and activated ash adsorbents were prepared from oyster shell. The physico-chemical properties of the prepared calcined oyster shell ash (COSA) and activated oyster shell ash (AOSA) were obtained using ASTM standards and Sears method. The results show that AOSA is a better adsorbent for removal of cyanide from cassava wastewater than COSA. The adsorption of cyanide from cassava wastewater onto adsorbents (COSA and AOSA) was investigated as a function of pH, adsorbent dosage, contact time, temperature and initial cyanide concentration. The batch study reveals that the adsorption process is strongly pH dependent and maximum cyanide removal is found to occur at pH of 10. The highest percent removal of cyanide from cassava wastewater was found at contact time of 80 minutes and 30oC. The effect of temperature on the adsorption process shows a small increase in the percent cyanide removal followed by a large decrease which suggests physical adsorption as the adsorption mechanism. The percent cyanide removal efficiency decreases with increase in initial cyanide concentration and increases with increase in adsorbent dosage.

Open Access Original Research Article

Design of Common-gate with Common-source Active Balun for WiMAX Receiver Front-end

Frederick Ray I. Gomez, Maria Theresa G. De Leon, John Richard E. Hizon

Journal of Engineering Research and Reports, Page 1-9
DOI: 10.9734/jerr/2019/v6i116939

This paper presents a design and simulation study of a common-gate with common-source active balun circuit implemented in a standard 90-nm complementary metal-oxide semiconductor (CMOS) process.  The active balun design is intended for worldwide interoperability for microwave access (WiMAX) application, with operating frequency of 5.8 GHz and supply voltage of 1 V.  Measurements are taken for parameters namely gain difference, phase difference, and noise figure.  The common-source active balun design achieved a minimal gain difference of  0.04 dB, phase difference of 180 ± 1.5 degrees, and noise figure of 8.76 dB, which are comparable to past active balun designs and researches.  The design eventually achieved a low power consumption of 4.45 mW.