Title: A Novel Non-intrusive Method to Diagnose Bearings Surface Roughness Faults in Induction Motors Author:Irfan, Muhammad Subject:Bearing localized faults ; Distributed faults ; Condition monitoring ; Instantaneous power analysis ; Noninvasive method Description:
Noninvasive condition monitoring methods are economical and easy to implement. An extensive research has been conducted in the past to diagnose bearing localized faults through noninvasive condition monitoring techniques. However, due to unavailability of the harmonic frequency model for bearing surface roughness faults, noninvasive techniques could not be used to diagnose such type of faults. This paper aims to mathematically derive a harmonic frequency model for bearing surface roughness faults using bearing geometry. The derived harmonic frequency model has been verified experimentally using noninvasive instantaneous power analysis technique. Laboratory tests have been performed on the inner and outer race surface roughness faults under no-load and full-load conditions to validate the approach.
Is part of:
Journal of Failure Analysis and Prevention, 2018, Vol.18(1), pp.145-152
1547-7029 (ISSN); 1864-1245 (E-ISSN); 10.1007/s11668-018-0398-4 (DOI)
Post-tuberculosis pulmonary function and noninfectious pulmonary disorders
International journal of mycobacteriology, December 2016, Vol.5 Suppl 1, pp.S57
[Peer Reviewed Journal]
Title: Characterization of maghemite (γ-Fe 2 O 3 )-loaded poly- l -lactic acid/thermoplastic polyurethane electrospun mats for soft tissue engineering Author:Fallahiarezoudar, Ehsan; Ahmadipourroudposht, Mohaddeseh; Idris, Ani; Yusof, Noordin; Marvibaigi, Mohsen; Irfan, Muhammad Subject:Infrared Spectroscopy – Mechanical Properties ; Fibrin – Usage ; Fibrin – Mechanical Properties ; Tissue Engineering – Mechanical Properties ; Skin – Mechanical Properties ; Iron Oxides – Usage ; Iron Oxides – Mechanical Properties ; Polyurethanes – Usage ; Polyurethanes – Mechanical Properties ; Organic Acids – Mechanical Properties; Description:
This study proposed a new mixture of three different biocompatible and biodegradable materials for soft tissue which needs elasticity and stretchability as well as stiffness. Five different ratios of poly- l -lactic acid (PLLA)/thermoplastic polyurethane (TPU) blend containing 1 % (w/v) maghemite (γ-Fe 2 O 3 ) nanoparticles were electrospun and characterized in terms of morphology, degradation rate, biological compatibility, and mechanical properties for tunable properties. Neat PLLA/TPU samples were used for maghemite effect verification. The existence of three components in the electrospun mats was confirmed by Fourier transform infrared spectroscopy and energy-dispersive X-ray spectroscopy. Scanning electron microscopy images illustrated well-fabricated nanofibers with smaller diameter distribution for PLLA. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay using human skin fibroblast cell indicates desired proliferation and migrant over the samples. Blood biocompatibility results in terms of clotting time, fibrin formation, and hemolysis were almost in the normal range. Samples’ degradation rate was investigated over 24 weeks where the PLLA shows 47.15 % mass change, while 6.7 % of TPU mass changed. High tensile strength and an extremely low elongation at break were determined from the stress–strain curve for PLLA, while TPU exhibits high elasticity. The 50:50 % ratio of 1 % (w/v) maghemite-loaded PLLA/TPU scaffold presents an overall satisfaction.
Is part of:
Journal of Materials Science, 2016, Vol.51(18), pp.8361-8381
0022-2461 (ISSN); 1573-4803 (E-ISSN); 10.1007/s10853-016-0087-1 (DOI)
Title: Noise Reduction Based on Soft Masks by Incorporating SNR Uncertainty in Frequency Domain Author:Saleem, Nasir; Irfan, Muhammad Subject:Ideal binary mask ; Noise reduction ; Residual noise ; Soft masking ; Intelligibility ; Quality ; Threshold Description:
The binary mask approach has been studied recently to reduce the background noise and improve the speech intelligibility and quality in the noisy surroundings. This mask is usually applied at the time–frequency illustration of a noisy speech and discards portions of a speech below a signal-to-noise-ratio (SNR) threshold, whereas allowing others to pass over intact. The threshold, however, is normally very low, and considerable residual noise would exist. Moreover, the precise estimate of local instantaneous SNR in practical applications is a difficult task. By modeling the local instantaneous SNR as Fisher–Snedecor distributed random variable, the soft masks for noise reduction are derived by incorporating SNR uncertainty in the frequency domain. Instead of finding a different method to estimate the local instantaneous SNR, the probability of local instantaneous SNR is computed higher than the threshold. The results indicated that soft masks yielded significantly better speech quality in terms of speech distortion and residual noise.
Is part of:
Circuits, Systems, and Signal Processing, 2018, Vol.37(6), pp.2591-2612
0278-081X (ISSN); 1531-5878 (E-ISSN); 10.1007/s00034-017-0684-5 (DOI)
G-AETCAM: Gate-Based Area-Efficient Ternary Content-Addressable Memory on FPGA
Title: Endobronchial tuberculosis-a review Author:Shahzad, Talha; Irfan, Muhammad Subject:Endobronchial Tuberculosis (Ebtb) ; Bronchoscopy ; Complications ; Endobronchial Obstruction ; Radiology Description:
Endobronchial tuberculosis (EBTB) is a tuberculous infection of the tracheobronchial tree with microbial and histopathological evidence. Patients may present with symptoms secondary to disease itself or from the complication of disease like endobronchial obstruction. Diagnosis requires a high index of suspicion. Computed tomography (CT) and bronchoscopy along with microbiological investigations are the most useful diagnostic tools for the confirmation as well as for the evaluation of the tracheobronchial stenosis. The goals of treatment are eradication of tubercle bacilli with anti-tubercular medications and the prevention of airway stenosis. Interventional Bronchoscopic techniques and surgery is required for those patients who develop severe tracheobronchial stenosis that causing significant symptoms including dyspnea, repeated post obstructive pneumonia or bronchiectasis.
Is part of:
Journal of thoracic disease, December 2016, Vol.8(12), pp.3797-3802
2072-1439 (ISSN); 28149579 Version (PMID); 10.21037/jtd.2016.12.73 (DOI)
Title: Segmented Loop Algorithm of Theoretical Calculation of Trajectory of Rockfall Author:Irfan, Muhammad; Chen, Yulong Subject:Rockfall ; Calculation method ; Engineering disaster ; Trajectory ; Segmented cycling algorithm Description:
Rockfall is a frequent engineering disaster confronted in the capital construction engineering. The key for preventing rock fall is the evaluation of the rockfall trajectory. After extensive analysis, an innovative calculation method of rockfall trajectory, called segmented cycling algorithm, has been proposed in the paper. According to the contact relationship between the rolling stones and the slope surface, the movement divided into three sections which include the bouncing phase, the rolling (sliding) phase and collision phase, the formulae to calculate the velocity of different phases of motion are proposed respectively by segmented cycling algorithm. A similar model, based on a rock slope in Chongqing–Wanzhou highway, is established to verify the capability and validity of the presented algorithm. Compared with existing algorithm, the new algorithm is simple and clear, easy to use and so on. The algorithm meets the law of the movement of rockfall and can be used to forecast the kinetic feature of rockfall. It is also used as the basis for rockfall disaster prevention.
Is part of:
Geotechnical and Geological Engineering, 2017, Vol.35(1), pp.377-384
0960-3182 (ISSN); 1573-1529 (E-ISSN); 10.1007/s10706-016-0113-8 (DOI)
Monetary Policy, Business Cycles and Sectoral Response in Pakistan
Jamil, Muhammad, Irfan, Muhammad
Acta Universitatis Danubius. Œconomica, 2016, Vol.12(4), pp.171-190
[Peer Reviewed Journal]