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Flashover voltage is considered one of the important factors affect the Power system reliability. Environmental conditions and filling of insulators are parameters should be considered in flashover voltage evaluation. In this work, laboratory studies are carried out on insulator with Alumina Trihydrate [ATH] filling at different concentration and different weather conditions to investigate the flashover voltage. The evaluation of flashover voltage is carried out at three conditions dry, wet and salt wet condition. In each test, four different lengths with different filling concentration are considered. Several curve fitting methods are used to obtain an equation of flashover voltage. The obtained equation first is only function of filling at different insulator lengths with approximately zero errors. Although the accuracy of this method, it gives flashover voltage only at discrete lengths. Thus, for continuous length validation the flashover is fitted again to be a function of both length and filling.

Robustness of a battery management system (BMS) is a crucial issue especially in critical application such as medical or military. Failure of BMS will lead to more serious safety issues such as overheating, overcharging, over discharging, cell unbalance or even fire and explosion. BMS consists of plenty sensitive electronic components and connected directly to battery cell terminal. Consequently, BMS exposed to high voltage potential across the BMS terminal if a faulty cell occurs in a pack of Li-ion battery. Thus, many protection techniques have been proposed since last three decades to protect the BMS from fault such as open cell voltage fault, faulty cell, internal short circuit etc. This paper presents a review of a BMS focuses on the protection technique proposed by previous researcher. The comparison has been carried out based on circuit topology and fault detection technique

This paper focuses on a Grid-Connected Photovoltaic (GCPV) system of amorphous Silicon (a-Si) PV module technology with total PV capacity is about 1.179 kWp. This a-Si FS GCPV system is located near to the Green Energy Research Centre (GERC) Building at Universiti Teknologi MARA (UiTM) Shah Alam, Malaysia. This a-Si FS GCPV system installation was referred to Malaysian Standard MS1837:2010 and designed based on initial data values. These days, various of the GCPV system applications in Malaysia using thin-film PV module technology was designed at stabilised data values. So, this a-Si PV system is conducted to study the PV performances and behaviors under Malaysia's perspective. After the observation period, a-Si FS GCPV system performs in good condition. The PV system generated 644.40 kWh electrical energy during the first six months of operation (June-December 2011) and the average daily energy yield of 3.03 kWh. The average monthly final yield was found to be 78.0 kWh/kWp, while the range of the initial/stabilized performance ratios between 55.8% to 78.2% and 73.0% to 102.4%.

The present study was carried out to evaluate the potential protective role of quercetin and curcumin against paracetamol-induced oxidative injury, liver damage and impairment of kidney function, as well as haematotoxicity in rats. Also, N-acetylcysteine was used to evaluate the potency of quercetin and curcumin. Paracetamol caused an elevation in thiobarbituric acid-reactive substances (TBARS) paralleled with significant decline in glutathione peroxidase, glutathione S-transferase, superoxide dismutase and catalase activities (in plasma, brain, lung, heart, liver, kidney and testes) and glutathione content (in lung, liver and kidney). The apparent oxidative injury was associated with evident hepatic necrosis confirmed in histological examination, elevated plasma transmainases, alkaline phosphatase and lactate dehydrogenase. Paracetamol reduced plasma total protein, albumin and globulin, while increased bilirubin, urea and creatinine, and induced haematotoxicity. The presence of quercetin or curcumin with paracetamol successfully mitigated the rise in TBARS and restored the activities of antioxidant enzymes compared to the group treated with both paracetamol and N-acetylcysteine. They also protected liver histology, normalized liver and kidney functions, which was more pronounced with curcumin. Therefore, it can be concluded that concomitant administration of quercetin or curcumin with paracetamol may be useful in reversing the toxicity of the drug compared to N-acetylcysteine.

Iron, zirconium and copper samples were irradiated at 17.5 K by 10 to 16 MeV protons. The resistivity change was measured as a function of the bombarding dose. Values of the resistivity damage rate are determined from the experimental data and are compared with the corresponding estimates obtained from a modified Kinchin-Pease model and from a vacancy-recombination model. Good agreement is found between the latter model and the experimental results. The data are also compared with other proton irradiation and d-Be neutron experiments.

Stage I recovery is investigated for Fe, Zr and Cu irradiated at 17.5 K with 10,14 and 16 MeV protons. Several sub-stages are measured and analyzed. In relation to published electron and neutron irradiation data, the present results show that 16 MeV protons approximate the damage induced in metals due to fusion reactor spectra. The present results also indicate that the damage state created by protons in metals is similar to an intermediate state between those due to electron and fast-neutron irradiations.

Iron and copper samples have been irradiated at 17K with 10–16 MeV protons to investigate the damage produced and, where possible, draw conclusions in relation to the use of such bombardments to simulate the damage resulting from the fusion neutron spectrum. The damage-dose behaviour and isochronal anneals appear to support the model of stimulated Frenkel-pair recombination in the vicinity of high energy density cascades.

The variation of lower yield stress with grain size has been established in niobium of two different levels of impurity. The results obey closely the Hall-Petch relationship, σy=σi + Kyd−12, with Ky⋍1.1 kg mm−32. The grain size dependence of the flow stress was found to obey a similar relationship, but with the parameter K < Ky, and increasing with strain. Niobium with ∼ 5 p.p.m. oxygen showed yield points after high temperature annealing, but was free from strain ageing effects in tensile tests above room temperature, and no recovery of yield phenomena was observed after ageing.

The design of a low temperature cryostat suitable for accelerator based radiation damage studies is presented. The system employs a commercial two-stage closed cycle helium gas cryorefrigerator and a mechanical heat switch to permit sample irradiations at 13–15 K and rapid temperatures cycling up to 300 K for post irradiation isochronal anneal studies. Al-In and Al-Ag switch contacts are evaluated for the cryostat.