Asraf M Moubark

National University of Malaysia | ukm · Department of Electrical, Electronic and Systems Engineering

This paper presents a conductive component tailored to a flexible substrate using Al-doped CoxCa(0.90−x)Ni0.10Fe2O4 (x = 0.25, 0.50, and 0.75) for visible to near-infrared (NIR) spectra in magneto-optical applications. The developed nanoparticles show uniformity, nanosized grains, and capillary nanopore fusion characteristics, which are confirmed b...

In this paper, a new metamaterial absorber (MMA) is presented that exhibits peak absorptions at 3.26 GHz, 11.6 GHz, and 17.13 GHz within S, X, and Ku bands. The unit cell of the proposed MMA is constructed on an FR4 substrate having an electrical dimension of 0.144λ × 0.144λ, where wavelength, λ is calculated at the lowest absorption frequency. The...

Glaucoma is a chronic eye disease that may lead to permanent vision loss if it is not diagnosed and treated at an early stage. The disease originates from an irregular behavior in the drainage flow of the eye that eventually leads to an increase in intraocular pressure, which in the severe stage of the disease deteriorates the optic nerve head and...

In ultrasound B-mode imaging, the axial resolution (AR) is commonly determined by the duration or bandwidth of an excitation signal. A shorter-duration pulse will produce better resolution compared to a longer one but with compromised penetration depth. Instead of relying on the pulse duration or bandwidth to improve the AR, an alternative method t...

This study examines epsilon-negative (ENG) and near-zero index (NZI) tunable cross-coupled (TCC) metamaterial (MTM) unit cells for multi-band wireless communications. The square split ring resonator (SSRR), a cross-coupled metallic element, and a star-like shape are added at the center of the resonator of the TCC MTM unit cell. The EMR value is 10....

Health pandemics such as Covid-19 have drastically shifted the world economics and boosted the development of automation technologies in the industries for continuous operation without human intervention. This paper elaborates on an approach to dynamically track and grasp moving objects using a robot arm. The robot arm has an eye-in-hand (EIH) conf...

Apples are one of the most consumed fruits, and they require efficient harvesting procedures to remains in optimal states for a longer period, especially during transportation. Therefore, automation has been adopted by many orchard operators to help in the harvesting process, which includes apple localization on the trees. The de facto sensor that...

An eye disease screening system is an important tool for health practitioners in performing mass screening tests at a low cost. Thus, the system is usually built for a mobile platform where the form factor is small and easily dispatched to rural areas. The system is also expected to perform automated decision-making with the help of the state-of-th...

Skin cancer is one of the major causes of death worldwide. It can be screened early by identifying certain types of skin lesion that correlates to the possibility of developing into full cancer cells. It is a difficult task to distinguish between multiple types of the lesion as their appearance do not differ that much. Thus, a modified DenseNet, wh...

As an alternative to delay-and-sum beamforming, a novel beamforming technique called filtered-delay multiply and sum (FDMAS) was introduced recently to improve ultrasound B-mode image quality. Although a considerable amount of work has been performed to evaluate FDMAS performance, no study has yet focused on the beamforming step size, Δx, in the la...

In this research paper, an inverse double V loaded complementary square split ring resonator based double negative (DNG) metamaterial has been developed and examined numerically and experimentally. The electromagnetic (EM) properties of the proposed inverse double V-structure were calculated using computer simulation technology (CST-2019) and the f...

Skeletal bone age assessment using X-ray images is a standard clinical procedure to detect any anomaly in bone growth among kids and babies. The assessed bone age indicates the actual level of growth, whereby a large discrepancy between the assessed and chronological age might point to a growth disorder. Hence, skeletal bone age assessment is used...

In recent years, the Ultrasound Group at the University of Leeds has developed an open platform (OP) known as Ultrasound Array Research Platform II (UARPII). The OP serves as a main component for researchers to test and implement new algorithms which is not feasible with the commercially available clinical scanners. In this paper, three types of ex...

The phase error caused by non-ideal physical transducer characteristics can affect the ultrasonic wave front during beamforming. If not compensated, the phase error can degrade the focusing capability and reduce the B-mode image spatial resolution. In this paper, the effect of the phase error on ultrafast coherent plane wave imaging (CPWI) was inve...

The phase error caused by non-ideal physical transducer characteristics can affect the ultrasonic wave front during beamforming. If not compensated, the phase error can degrade the focusing capability and reduce the B-mode image spatial resolution. In this paper, the effect of the phase error on ultrafast coherent plane wave imaging (CPWI) was inve...

This study aimed to estimate angled tissue motion for shear wave compounding applications. Shear wave elastography produces the quantitative elasticity biomarker for assessing the health status of tissues. In sheer wave compounding, steered shear waves are generated with different angles, and individual angle elasticity maps are averaged to improve...

Compounding techniques have been used in ultra-fast ultrasound imaging to improve image quality by reducing clutter noise, smoothing speckle variance and enhancing its spatial resolution at the cost of reducing frame rate. However, the reduction of clutter noise and side lobes inside the anechoic regions is minimal when combining conventional spati...

In medical ultrasound B-mode imaging, by increasing the image contrast, spatial and temporal resolution, it will help to improve the diagnostic and decision making process. Previously the unsharp masking (UM) techniques have been successfully implemented for digital image processing as edge enhancement techniques. However, the outcomes of the metho...

FDMAS beamforming technique have been employed with low number of steering angles and smaller lateral steps in order to improve the image quality for better cyst classification. Taking advantage of the autocorrelation process in FDMAS, lateral steps were reduced in order to calculate the time delay for the RF signal more accurately. The new beamfor...

Improving the ultrasound image contrast ratio (CR) and contrast to noise ratio (CNR) has many clinical advantages. Breast cancer detection is one example. Anechoic cysts which fill with clutter noise can be easily misinterpreted and classified as malignant lesions instead of benign. Beamforming techniques contribute to off-axis side lobes and clutt...

The plane wave imaging challenge (PICMUS) has been introduced for the first time to IUS in order to encourage participants to compete and share their knowledge in medical ultrasound plane wave imaging. To participate in this challenge, we have chosen the contrast enhanced delay and sum (CEDAS) post signal processing method. This technique have been...

Photoacoustic imaging is used to differentiate between tissue types based on light absorption. Different structures, such as vascular density of capillaries in human tissue, can be analysed and provide diagnostic information to detect early stage breast cancer. Delay and sum (DAS) beamforming is the traditional method to reconstruct photoacoustic i...

FDMAS has been successfully used in microwave imaging for breast cancer detection. FDMAS gained its popularity due to its capability to produce results faster than any other adaptive beamforming technique such as minimum variance (MV) which requires higher computational complexity. The average computational time for single point spread function (PS...

In compound plane wave imaging (CPWI), multiple plane waves are used to insonify the imaging region with different steering angles. The compounding operation is effectively a spatial averaging filter that reduces the speckles of the image and increases the image contrast and its lateral resolution. Although spatial averaging often improves CPWI ima...

This research paper discusses the two strategies used in monitoring and improving the performance of the students from the Department of Electrical, Electronics and System Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia. The first strategy is the online mentor mentee system, also known as e-Mentor Mentee st...

In compound plane wave imaging (CPWI), multiple plane waves are used to insonify the imaging region with different steering angles. The compounding operation is effectively a spatial averaging filter that reduces the speckles of the image and increases the image contrast and its lateral resolution. Although spatial averaging often improves CPWI ima...

This paper proposes a new developed system named Access Control System (ACS) which is designed to enhance the monitoring, scalability and survivability of Passive Optical Network (PON) toward the implementation of full & Complete edition of Fiber-to-the Network (FTTH) network. The system automatically identifies faults and controls each optical fib...

Multithreading programming can improve performance of an application especially to reduce processor busy waiting. Typically, threads that have to wait for input/output responses can wait in a queue (sleep queue), allowing other threads to utilize processor, therefore improving system timeliness and throughput. As such an application can be partitio...