Electric power in ASEAN countries: A shifting fuel mix

After the oil shocks of 1973 and 1979, the ASEAN countries took measures to lessen their dependence on oil. Their concern is reflected in the electric power sector, the largest single end-user of primary energy in most countries. This article describes how the ASEAN countries are shifting the pattern of their fuel mix for electric power generation from oil to other sources of energy, with a preference for domestic energy resources. Singapore, which has no indigenous energy resources, is the single exception. Data from Brunei are not yet available.     

An EFSM-Based Test Data Generation Approach in Model-Based Testing

Testing is an integral part of software development. Current fast-paced system developments have rendered traditional testing techniques obsolete. Therefore, automated testing techniques are needed to adapt to such system developments speed. Model-based testing (MBT) is a technique that uses system models to generate and execute test cases automatically. It was identified that the test data generation (TDG) in many existing model-based test case generation (MB-TCG) approaches were still manual. An automatic and effective TDG can further reduce testing cost while detecting more faults. This study proposes an automated TDG approach in MB-TCG using the extended finite state machine model (EFSM). The proposed approach integrates MBT with combinatorial testing. The information available in an EFSM model and the boundary value analysis strategy are used to automate the domain input classifications which were done manually by the existing approach. The results showed that the proposed approach was able to detect 6.62 percent more faults than the conventional MB-TCG but at the same time generated 43 more tests. The proposed approach effectively detects faults, but a further treatment to the generated tests such as test case prioritization should be done to increase the effectiveness and efficiency of testing.     

Biomechanical analysis of rheumatoid arthritis of the wrist joint

The wrist is the most complex joint for virtual three-dimensional simulations, and the complexity is even more pronounced when dealing with skeletal disorders of the joint such, as rheumatoid arthritis (RA). In order to analyse the biomechanical difference between healthy and diseased joints, three-dimensional models of these two wrist conditions were developed from computed tomography images. These images consist of eight carpal bones, five metacarpal bones, the distal radius and ulna. The cartilages were developed based on the shape of the available articulations and ligaments were simulated via mechanical links. The RA model was developed accurately by simulating all ten common criteria of the disease related to the wrist. Results from the finite element (FE) analyses showed that the RA model produced three times higher contact pressure at the articulations compared to the healthy model. Normal physiological load transfer also changed from predominantly through the radial side to an increased load transfer approximately 5% towards the ulnar. Based on an extensive literature search, this is the first ever reported work that simulates the pathological conditions of the rheumatoid arthritis of the wrist joint.     

Microwave-accelerated ultrafast nanoparticle aggregation assays using gold colloids

In this paper, the proof of principle of microwave-accelerated aggregation assay technology, which shortens the solution-based aggregation assays' run time to seconds (>100-fold increase in kinetics) with microwave heating, was demonstrated using a model aggregation assay based on the well-known interactions of biotin and avidin. Biotinylated gold colloids were aggregated in solution with the addition of streptavidin, which takes 20 min at room temperature to reach >90% completion and only 10 s with microwave heating. The initial velocity (after 1-s microwave heating) of the biotinylated gold colloids reaches up to 10.5 m/s, which gives rise to greater sampling of the total volume but not a large increase in bulk temperature. The room-temperature, steady-state velocity of the colloids was <0.5 microm/s. In control experiments, where streptavidin preincubated with d-biotin in solution is added to biotinylated gold colloids and microwave heated, gold colloids did not aggregate, demonstrating that nonspecific interactions between biotinylated gold colloids and streptavidin were negligible.     

Safety profiles of total dose infusion of low-molecular-weight iron dextran and high-dose iron sucrose in renal patients

Iron sucrose and low-molecular-weight iron dextran (LMW-ID), two commonly used iron solutions, have been compared in terms of allergic adverse event profiles to date. However, the safety of total dose infusion of LMW-ID has been investigated by only one study in chronic kidney disease (CKD) (not dialysis) patients. Thus, we aimed to compare adverse event profiles of total and high-dose LMW-ID and iron sucrose infusions in a heterogenous renal patient group comprising CKD, hemodialysis, and peritoneal dialysis. In this retrospective chart review study, we included 110 predialysis CKD, 101 peritoneal dialysis, and 118 hemodialysis patients. We included a total of 329 patients who were administered parenteral iron sucrose or LMW-ID between September 2006 and April 2010. Adverse events were determined both by medical and nursing follow-up notes. Laboratory data and clinical characteristics were collected from patient charts. Adverse event rates were compared between iron sucrose and LMW-ID infusions. In a total of 329 patients, 530 infusions (3470 ampules) were administered. We detected adverse reaction in only 1 patient. This adverse reaction, which manifested as generalized pruritus, occurred in a patient who received 500 mg of iron sucrose infusion. There were neither anaphylactic reactions nor deaths associated with infusion of either preparation. We did not observe any other adverse event related to administration of 500 and 1000 mg of iron sucrose at single infusion. The results of this study showed comparable safety of total dose LMW-ID and high-dose iron sucrose in a heterogenous group of renal patients.     

Biodegradable zinc-based materials with a polymer coating designed for biomedical applications

Over the last decades, biodegradable metals have gained popularity for biomedical applications due to their ability to assist in tissue healing. These materials degrade in vivo, while the corrosion products formed are either absorbed or excreted by the body, and no further surgical intervention is required for removal. Intensive research has been carried out mainly on degradable biomaterials based on Mg and Fe. In recent years, zinc-based degradable biomaterials have been explored by the biomedical community for their intrinsic physiological relevance, desirable biocompatibility, intermediate degradation rate, tuneable mechanical properties and pro-regeneration properties. Since pure Zn does not exhibit sufficient mechanical properties for orthopedic applications, various Zn alloys with better properties are being developed. In this work, the combined effect of minor Fe addition to Zn and a polyethyleneglycol (PEG) coating on the surface morphology, degradation, cytotoxicity and mechanical properties of Zn-based materials was studied. There are several studies regarding the influence of the production of Zn alloys, but the effect of polymer coating on the properties of Zn-based materials has not been reported yet. A positive effect of Fe addition and polymer coating on the degradation rate and mechanical properties was observed. However, a reduction in biocompatibility was also detected.     

An elucidation of symmetric supercapacitor with crustacean-based polymer blend electrolyte

Searching for alternative materials that have biodegradable properties is one of the efforts to increase knowledge and green technology that contributes to the reduction of waste produced from electronics. A biodegradable biopolymer electrolyte system based on polyvinyl alcohol-chitosan blend is prepared using an easy and affordable method called solution cast technique. Lithium acetate (LiOAc) and ethylene carbonate (EC) are incorporated as charge carrier and plasticizing agent. The plasticization effect of EC concentrations on physical structure has been investigated and reported. The real and imaginary parts of dielectric permittivity confirmed that the highest dielectric constant and loss values are recorded at low-frequencies regions. A disruption in the crystalline region of the film can be observed with the existence of LiOAc and EC. The inclusion of EC promotes the ions dissociation thus enhanced the amorphous region of the electrolytes which is beneficial for ionic conduction. Linear sweep voltammetry analysis revealed that the highest conducting electrolyte is electrochemically stable up to 1.82 V. No redox peaks are shown in the cyclic voltammetry of the fabricated supercapacitor. The supercapacitor showed a great performance with average specific capacitance of 130 F g⁻¹.     

Effects of hydrogenation of fossil fuels with hydrogen and hydroxy gas on performance and emissions of internal combustion engines

Energy security is an important consideration for development of future transport fuels. Among the all gaseous fuels hydrogen or hydroxy (HHO) gas is considered to be one of the clean alternative fuels. Hydrogen is very flammable gas and storing and transporting of hydrogen gas safely is very difficult. Today, vehicles using pure hydrogen as fuel require stations with compressed or liquefied hydrogen stocks at high pressures from hydrogen production centres established with large investments.Different electrode design and different electrolytes have been tested to find the best electrode design and electrolyte for higher amount of HHO production using same electric energy. HHO is used as an additional fuel without storage tanks in the four strokes, 4-cylinder compression ignition engine and two-stroke, one-cylinder spark ignition engine without any structural changes. Later, previously developed commercially available dry cell HHO reactor used as a fuel additive to neat diesel fuel and biodiesel fuel mixtures. HHO gas is used to hydrogenate the compressed natural gas (CNG) and different amounts of HHO-CNG fuel mixtures are used in a pilot injection CI engine. Pure diesel fuel and diesel fuel + biodiesel mixtures with different volumetric flow rates are also used as pilot injection fuel in the test engine. The effects of HHO enrichment on engine performance and emissions in compression-ignition and spark-ignition engines have been examined in detail. It is found from the experiments that plate type reactor with NaOH produced more HHO gas with the same amount of catalyst and electric energy. All experimental results from Gasoline and Diesel Engines show that performance and exhaust emission values have improved with hydroxy gas addition to the fossil fuels except NO_x exhaust emissions. The maximum average improvements in terms of performance and emissions of the gasoline and the diesel engine are both graphically and numerically expressed in results and discussions. The maximum average improvements obtained for brake power, brake torque and BSFC values of the gasoline engine were 27%, 32.4% and 16.3%, respectively. Furthermore, maximum improvements in performance data obtained with the use of HHO enriched biodiesel fuel mixture in diesel engine were 8.31% for brake power, 7.1% for brake torque and 10% for BSFC.