The Effect of Edm Die-sinking Parameters on Material Removal Rate of Beryllium Copper Using Full Factorial Method

The effect of electrical discharge machining (EDM) die-sinking parameters on material removal rate (MRR) of Beryllium Copper (BeCu) was studied. EDM die-sinking is one of the important non-traditional machining processes and it is widely accepted as a standard machining process in the manufacturing of forming tools to produce mould and die. The appropriate parameters were selected to study the influence of operating parameters of BeCu on MRR. Electrolytic copper was selected as electrode with positive polarity. The experiment was done using SODICK AQ35L EDM machine. Two level approach of full factorial design of experiment was applied to design the experimental and the data was analyzed by using analysis of variance (ANOVA) and the optimal combinations of the process parameters were predicted. It is found that peak current was the most significant factor affecting the MRR. Further, pulse on time and pulse off time must be combined with other factors in order to influence the machining characteristics. Finally, machine voltage shows less significant factor for the EDM die-sinking process on BeCu

Properties of fly ash concrete containing tropical soil bacteria

The autonomous crack healing process using microbiologically induced calcium carbonate precipitation (MICP) is a sustainable alternative to overcome propagation of micro-cracks and restore the durability of concrete. This paper presents the potential use of tropical soil bacteria as a self-healing agent for fly ash concrete. A solution of 107 cells/mL Lysinibacillus sphaericus (L. sphaericus), was selected to be the self-healing agent by replacing partially the amount of water. Concrete cube specimens with 30% fly ash, were cured under two conditions, which are water and air curing. The potential effects of the self-healing agent was evaluated in terms of the ultrasonic pulse velocity (UPV), initial surface absorption test (ISAT) and compressive strength. The initial results show an improvement of UPV and between 12% and 54% improvement on the compressive strength for the bacterial concrete compared to the control specimen. It was probably due to the presence of the microbial calcium carbonate that fills the concrete pores through the inclusion of bacteria in the concrete. However, based on the ISAT value, the direct addition of bacterial solution increased the concrete's permeability. Thus, further investigation is suggested to assess the self-healing effect towards permeability and compressive strength of bacterial concrete

New Design of a Low Cost Small Engine Dynamometer for Engine Testing

This paper discusses the design and development of a low cost small engine dynamometer for engine testing to measure engine performance i.e. power, torque and specific fuel consumption. The data and result were achieved by using a small hydraulic engine dynamometer with specific considerations and standard followed in order to have good engine dynamometer. Small engine was used by coupling it with the hydraulic pump that come with the control valve and pressure gauge. Control valve was set to build back pressure inside the pumping area. When the engine starts, the pressure gauge will give a reading which can be used to calculate the engine torque. By using the engine torque, engine power can be obtained by multiplying the angular speed with engine torque. Specific fuel consumption can be defined, by dividing the brake engine power with the fuel rate. From the experiment data, the brake power of the single cylinder engine showed that it is almost similar to the specification given by the manufacturer. The low cost hydraulic engine dynamometer, which is less than RM 15,000 can be used to measure an engine performance. The engine power, torque, engine speed and air fuel ratio data can be achieved from our developed engine dynamometer

Product And Tooling Design Of Slanted Glass Injection Mould For Visualization Of Flow Molten Plastic

A two-plate plastic injection mould having a new method of embedded slanted glass at mould cavity side is designed where it can be used to visualize the flow of molten plastic material moving inside the mould cavity. Due to observation of molten plastic materials cannot be done in actual mould made from metal, therefore slanted glass mould is developed. This project shows the design process of slanted glass mould from initial plastic product design until mould tooling design. The plastic product and the slanted glass mould were designed using SolidWorks software. In designing and producing the injection molded plastic product, various factors are needed to be considering such as corner radius, draft angle and the product wall thickness Two different geometrical shapes of plastic products have been designed that were the flat and ring plastic product. Meanwhile for mould tooling design, the method to capture the flow pattern of molten plastic materials is the most considering factor in this project. Others considering factors included are location of feeding system, tolerance fitting and water cooling system. Thus, this project helps mould designer the important of design process should be considered during plastic design and tooling design especially for slanted glass injection mould

The impact of off-pump coronary artery bypass surgery on postoperative renal function.

OBJECTIVES: A number of risk factors have been recognised for postoperative renal dysfunction following on-pump coronary artery bypass surgery (CABG). There are, however, few studies that have evaluated the potential reno-protective effects of off-pump CABG in the presence of other confounding risk factors. The aim of this study was to determine if off-pump CABG reduces the risk of renal injury. METHODS: Serum creatinine values (preoperatively and day 1, 2 and 4 postoperatively) and other clinical data were prospectively collected on 1580 consecutive patients who underwent first-time CABG from 2002 to 2005. Creatinine clearance was calculated using the Cockcroft and Gault equation. The effect of on-pump vs. off-pump CABG on renal function was analysed, adjusting for age, gender, diabetes mellitus, left ventricular (LV) function and preoperative creatinine clearance, using multiple regression analysis. RESULTS: One thousand one hundred and forty-five (73%) patients underwent on-pump CABG and 435 (27%) underwent off-pump CABG. The two groups were similar with respect to age, gender and diabetes. Two hundred and seventy-four (17%) patients were females and 274 (17%) patients had diabetes. Multivariate analysis demonstrated significantly lower creatinine clearance postoperatively in patients with diabetes (P<0.001) and advanced age (P<0.001). The on-pump group had significantly lower postoperative creatinine clearance in comparison to the off-pump group (P= 0.01). The effect remained consistent after adjusting for potential risk factors (age, diabetes, gender, LV function and preoperative creatinine clearance) in the multivariate analysis. CONCLUSION: Off-pump surgery is associated with a reduction in postoperative renal injury

The Effect of Endophytic <i>Talaromyces pinophilus</i> on Growth, Absorption and Accumulation of Heavy Metals of <i>Triticum aestivum</i> Grown on Sandy Soil Amended by Sewage Sludge

Sewage sludge improves agricultural soil and plant growth, but there are risks associated with its use, including high heavy metal content. In this study, experiments were carried out to investigate the role of endophytic Talaromyces pinophilus MW695526 on the growth of Triticum aestivum cultivated in soil amended with sewage sludge and its phytoremediation ability. T. pinophilus could produce gibberellic acid (GA) and stimulate T. aestivum to accumulate GA. The results showed that inoculation with T. pinophilus boosted plant growth criteria, photosynthetic pigments, osmolytes (soluble proteins, soluble sugars and total amino acids), enzymatic antioxidants (catalase, superoxide dismutase and peroxidase), K, Ca and Mg. On the other hand, it reduced Na, Na/K ratio, Cd, Ni, Cu and Zn in the growth media as well as in the shoot and root of T. aestivum. The results suggest that endophytic T. pinophilus can work as a barrier to reduce the absorption of heavy metals in T. aestivum cultivated in soil amended with sewage sludge