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This paper presents the distinct advantages of stator fault detection using a novel radial flux sensing technique. Intensive research efforts in the past have been focused on the flux signature analysis as they have been more efficient compared to classical motor current signature analysis. In this paper, it is observed that a flux sensing simple internal observer coil (OC) is more succinct than external flux sensors. The proposed simplified, inexpensive technique has yet not been reported in the literature. The new results of root mean square (RMS), fundamental, third harmonic, and total harmonic distortion analysis of the voltage spectra of the OCs are found to exhibit variations in relation to the severity of interturn faults as compared to the healthy condition. The mathematical theory of the technique is provided and supported by an experimental validation. An experiment for confirming the performance of the proposed method was done on a 2.2-kW three-phase four-poles, 440-V squirrel-cage induction motor, increasing the fault level in steps from 1% to 15% combined with variations in load from no load to full load. [ABSTRACT FROM AUTHOR]

Aim The burden of Type 2 diabetes is alarmingly high in South Asia, a region that has many genetically diverse ethnic populations. Genome-wide association studies ( GWAS) conducted largely in European populations have identified a number of loci predisposing to Type 2 diabetes risk, however, the relevance of such genetic loci in many South Asian sub-ethnicities remains elusive. The aim of this study was to replicate 49 single nucleotide polymorphisms ( SNPs) previously identified through GWAS in Punjabis living in Pakistan. Methods We examined the association of 49 SNPs in 853 Type 2 diabetes cases and 1945 controls using additive logistic regression models after adjusting for age and gender. Results Of the 49 SNPs investigated, eight showed a nominal association ( P < 0.05) that also remained significant after controlling for the false discovery rate. The most significant association was found for rs7903146 at the TCF7L2 locus. For a per unit increase in the risk score comprising of all the 49 SNPs, the odds ratio in association with Type 2 diabetes risk was 1.16 (95% CI 1.13-1.19, P < 2.0E-16). Conclusion These results suggest that some Type 2 diabetes susceptibility loci are shared between Europeans and Punjabis living in Pakistan. [ABSTRACT FROM AUTHOR]

Slot antennas are generally preferred for localized liver cancer treatment modalities due to desired radiation characteristics. An iterative thermal/microwave numerical routine is used to analyze regular and miniature slot antenna configurations at 5.8 GHz. A thermal/microwave solver determines the specific absorption rate to malignant tissues as a pre- processing step to compute microwave solution in terms of propagation wave number, return loss and insertion loss. The regular and miniature dual slots antenna geometries were then developed to estimate the return loss characteristics against antennas slot lengths at a constant frequency of 5.8 GHz. Results reveal that the regular geometry has return loss less than −5 dB as compared to <−25 dB return loss for miniature slot antenna configuration. Furthermore, 5.8 GHz antenna geometry provides physical size reduction up to 50 %, lower fabrication cost and is a better minimally invasive choice due to further packed thermal ablation spots. [ABSTRACT FROM AUTHOR]

The impact of occupational radiation exposures on oncology staff working in the disciplines of Nuclear Medicine (NM), Radiotherapy (RT), and Diagnostic Radiology (DR) is of significance to ensure a health risk free environment. In this study, occupationally received radiation doses amongst Pakistani oncology staff in NM, RT and DR during the period (2003-2012) were assessed. The Film Badge Dosimetry (FBD) technique has been utilized to process over 81,000 films (13,237 workers) concerning the occupationally exposed workers data (2003-2012) at a national scale. The annual effective doses were found to range between 0.30-0.97 mSv for NM, 0.44-1.02 mSv for RT and 0.31-1.09 mSv for DR. The annual effective doses averaged over a period of 10 years were assessed to be 0.63, 0.70 and 0.68 mSv for NM, RT and DR respectively. The exposure data were categorized into three exposure levels (≤0.99, 1-4.99 and 5-9.99 mSv) to establish the staff distribution in these categories. It was found that 89.8-96 % in NM, 82-94.5 % in RT and 76-96.8 % staff workers in DR have received doses within the range from the Minimum Detectable Limit (MDL)- 0.99 mSv. The annual effective doses, in all categories, were measured to be less than the recommended annual limit of 20 mSv. [ABSTRACT FROM AUTHOR]

Slot antennas are often considered as a suitable choice for microwave ablation due to design simplicity, low cost to manufacture and a highly confined temperature profile. In this paper, an iterative coupled thermal/microwave numerical formulation is presented to analyze and develop miniature slot antenna geometries for localized liver cancer treatment. The thermal solver determines the specific absorption rate (SAR) as a pre-processing step to determine the temperature distribution profile within malignant tissues. The microwave solver uses this computed thermal solution together with related boundary/sub-domain settings to determine complex propagation wave number as an Eigen value. The desired microwave response in terms of insertion loss <0.1 dB, VSWR 1:1.1, and return loss less than −22 dB was achieved at 2.45 GHz. The simulated results agree well with the measured response. [ABSTRACT FROM AUTHOR]

The dosimetric inter-comparison studies carry pertinent significance to ensure uniform radiation dose delivery for clinical trials. This paper investigates the comparative performance analysis of an X-ray high power linear accelerator performed by the International Dosimetry Survey Mission and institute of Nuclear Medicine & Oncology (INMOL), Lahore. The measurements were made using cylindrical ionization chambers based on the International Atomic Fnergy Agency (IAHA) TRS-398 protocol for absorbed dose-to-water dosimetric standards, and the percentage deviation was found to be between 0. 5% - 1 % . The dosimetric analysis concerning linear X-ray accelerator output performed by INMOL, Lahore was found to be in good agreement with the results of I AHA Dosimtery Survey Mission. [ABSTRACT FROM AUTHOR]

Phthalates are semivolatile organic compounds with a ubiquitous environmental distribution. Their presence in indoor environments is linked to their use in a variety of consumer products such as children's toys, cosmetics, food packaging, flexible PVC flooring among others. The goal of this study was to investigate the occurrence and concentration of phthalates in dust from homes in Kuwait and to assess non-dietary human exposure to these phthalates. Dust samples were randomly collected from 21 homes and analyzed for eight phthalates. The concentrations of total phthalates were log normally distributed and ranged from 470 to 7800 μg/g. Five phthalates [ Di(2-ethylhexyl) phthalate ( DEHP), Di-n-octyl phthalate ( Dn OP), Di-n-butyl phthalate ( DBP), Benzyl butyl phthalate ( Bz BP), and Dicyclohexyl phthalate ( Dc HP)] were routinely detected. The major phthalate compound was DEHP at a geometric mean concentration of 1704 μg/g (median, 2256 μg/g) accounting for 92% of the total phthalates measured. Using the measured concentrations and estimates of dust ingestion rates for children and adults, estimated human non-dietary exposure based on median phthalate concentrations ranged from 938 ng/kg-bd/day for adults to 13362 ng/kg-bd/day for toddlers. The difference in exposure estimates between children and adults in this study supports previous reports that children are at greater risk from pollutants that accumulate indoors. [ABSTRACT FROM AUTHOR]

Careful design of the magnetic bias circuit used in ferrite phase shifters can help to reduce space, weight and energy consumption. Low reluctance circuits must avoid air-gaps and this can be achieved using toroidal-shaped ferrite inserts positioned inside a rectangular waveguide. Here, these ferrite inserts are fabricated using a viscous plastic processing method that avoids machining and produces a continuous magnetic circuit. Finite-element methods are used to initially model the magnetostatic solution for the bias circuit before being used to analyse the microwave performance of a double toroid phase shifter. A closed-form technique is introduced to model the dielectric slab waveguide impedance transformer. The final insertion loss was <1 dB over the 9.5–10.3 GHz band and return loss of 20 dB was achievable. The phase shift calculation agrees to within 10% of the measured values. [ABSTRACT FROM AUTHOR]

A full design capability for electromagnetic waveguides should include the field solution, the modal hierarchy, impedance models, the cut-off and propagation planes with the ability to optimise parameters and synthesise designs. As cut-off frequencies and optimisation are problematic for numerical methods, closed-form solutions are always preferred. In this article, we reformulate Maxwell's equations into two coupled potential equations to characterise both E-plane and H-plane slab loaded waveguides. An experimental resonant cavity is constructed to confirm the dispersion characteristics of the single broadwall H-plane slab and a quarter wavelength impedance transformer is designed to match a toroidal ferrite phase shifter to rectangular waveguide. [ABSTRACT FROM AUTHOR]

The positive features of neural networks and fuzzy logic are combined together for the detection of stator inter-turn insulation and bearing wear faults in single-phase induction motor. The adaptive neural fuzzy inference systems (ANFISs) are developed for the detection of these two faults. These faults are created experimentally on a single-phase induction motor in the laboratory. The experimental data is generated for the five measurable parameters, viz, motor intakes current, speed, winding temperature, bearing temperature, and the noise of the machine. Earlier, the ANFIS fault detectors are trained for the two input parameters, i.e., speed and current, and the performance is tested. Later, the three remaining parameters are added and the five input ANFIS fault detector is trained and tested. It observed from the simulation results that the five input parameter system predicts more ac- curate results. [ABSTRACT FROM AUTHOR]