Magnetic torque obtained using finite element modelling of electromagnetic micro relay / Azahar Taib, Mohamad Adha Mohamad Idin and Nor Azlan Othman

Micro Electromechanical Systems (MEMS) is an area of research and applications that is becoming increasingly popular. One of MEMS device that is becoming increasingly important in a wide range of industries such as the computer industry, the medical industry and the automotive industry is micro relay. Generally, there are three types of micro relay based on actuation methods; electrostatic, electrothermal and electromagnetic. This research project focuses on electromagnetic micro relay. The need to study the magnetic behavior of electromagnetic micro relay is due to ongoing demand in area of micro relay design and fabrication. This study will focus on analyzing the magnetic behaviors of a specific electromagnetic micro relay. It involves the analytical and finite element modeling. The results from these two analyses are compared in order to verify the reliability of results obtained. Prior to the validation, a complete model of micro relay is developed using finite element modeling via ANSYS software. Investigations on magnetic behaviors of the electromagnetic micro relay are performed via Finite Element Analyses. By varying the current density on the EM planar coil on the micro relay structure, the operating principle of electromagnetic micro relay can be simulated and observed. In addition, it also includes the investigation of magnetic torque upon the armature of the micro relay when certain parameters are varied. The parameters are the thickness of the armature, air gap between the permanent magnet and EM planar coil, and the amount of current density applied to EM planar coils. The effect of the parameter's variation are presented and discussed. These results provide a good insight of the magnetic behavior of the investigated electromagnetic micro relay which will be very useful in designing an electromagnetic micro relay

Finite element modelling of fixed-fixed end plate attached with vibration absorber

The present paper investigated the effect of the lightweight dynamic vibration absorber (LDVA) to reduce vibration of thin walled structure. The free and forced vibration response of a rectangular thin plate were performed using finite element method. Subsequently, the effects of attached single and dual LDVA were analysed in depth by using Ansys workbench 14.5. Results demonstrated that single LDVA attached at the centre of the plate succesfully attenuate vibration over the frequency range of 0- 600 Hz. By contrast, attached with dual LDVA only suppresses the resonance of the first second and fourth modes but not for third and fifth modes of thin walled structure. It was found that by simply increasing the weight of mass does not improve the vibration absorption over the entire frequency range. The study conclude that attached single LDVA are better than dual LDVA for vibration absorption of thin walled structure over the entire frequency range

Nutritional status of children living with HIV and receiving antiretroviral (ARV) medication in the Klang Valley, Malaysia.

Nutrition and HIV are closely related. Any immune impairment as a result of HIV leads to malnutrition, which in turn, can also lead to reduced immunity, thus contributing to a more rapid progression to AIDS. Methods: This cross-sectional study determined the nutritional status of children living with HIV and are receiving antiretroviral medication in the Klang Valley. A total of 95 children aged one to eighteen years old were recruited between September 2008 and February 2009. Data collected included socio-economic status, anthropometric measurements, dietary intake, medical history and serum levels of selected micronutrients specific for immunity. Results: The mean age of the children was 8.4±3.9 years and the mean duration on antiretroviral medications was 68.3±38.3 months. Anthropometric assessment found that 9.5% of the children were underweight and 31.6% were overweight. In contrast, 20.8% were stunted and 14.6% severely stunted. Biochemical indicators showed that 10.4% had deficiency in vitamin A while 12.5% had deficiency in selenium. Total cholesterol and HDL-C levels were found to be low in 30.5% and 10.5% of the children respectively. Conclusion: Dietary assessment showed almost all the children did not achieve the recommended energy intake for their age groups and almost half of the children did not achieve the RNI for selenium and vitamin A. This study provides an insight on the nutritional status of children living with HIV

Rainfall-induced landslide thresholds development by considering different rainfall parameters: a review

This paper reviews the development of landslide thresholds from the perspective of rainfall and climate patterns. For certain, geology, morphology, lithology, etc., contribute to the initiation of the mass movement. However, the role of rainfall as the triggering mechanism of the landslide is vital as well. It has been proven by many researchers from various studies worldwide that have proposed the rainfall thresholds by utilising different rainfall parameters. The outcome of their studies is interesting, since different regions have diversified patterns of rainfall that produce a variety of threshold models. Therefore, from various published papers on rainfall thresholds, this paper studied the variety of rainfall parameters that have been utilised in establishing the rainfall threshold for landslide prediction. Instead of providing a better understanding regarding the application, this review aimed to cultivate the folllowing study for deriving rigorous parameters for the purpose of sustainable findings

Kaedah pengesanan automatik salur darah retina untuk imej digital fundus

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Empirically based rainfall threshold for landslides occurrence in Cameron Highlands, Malaysia

High-intensity rainfall has been recognized as the main factor of the landslide events in Cameron Highlands. Locating at an abrupt altitude with high intensity rainfall annually caused many attempts of slope failures in this area. This catastrophe weakens the socio-economy and situates the people of Cameron Highlands in difficulty since they lost their source of income. The application of the early warning system is one of the effective methods to reduce the losses from this unforeseen circumstance. It could be coordinated by developing a dependable rainfall intensity-duration (I-D) threshold for estimating the shallow landslide. By identifying twelve historical landslides in Cameron Highlands, the important variables from the rainfall intensity-duration parameter can be acquired. The proposed empirical rainfall intensity-duration (I-D) threshold for Cameron Highlands has been figured out as 0..075 I D 29.09 − = (I = rainfall intensity in mm/hr and D = duration in hour). Furthermore, to identify the formulation of I-D threshold from other regions, a comparison has been carried out by identifying the I-D threshold proposed by various researchers, which shows a reasonably higher value for the I-D thresholds of Cameron Highlands. This trend occurs due to the fact that rainwater requires more time to adequately seep into the thicker layer of soil in order to trigger the slope failure