Bilal Amin | Abdul Wali Khan University Mardan (original) (raw)

Drafts by Bilal Amin

kepler by Quaternionn, 2018

In the past, Kepler painstakingly derived laws of planetary motion using difficult to understand ... more In the past, Kepler painstakingly derived laws of planetary motion using difficult to understand and hard to follow techniques. In 1843 William Hamilton created and described the quaternions, which extend the complex numbers and can easily describe rotations in three dimensional space. In this article, we will harness this system to provide a new and intuitive way to derive Keplers laws. This will include solving the spatial Kepler problem using a quaternionic version of the differential equation, and using the general solution to describe the motion of planets orbiting a central body. We use the standard method for regularizing celestial mechanics, but this article will be solely focused on showing the validity of Kepler's laws. I. THE STAR CONJUGATE In order to describe the KS transformation in the form of quaternions we require a new operation that will remove the fourth dimension for any general quaternion. This setup was suggested by Waldvogel 1. We define the star conjugate of a quaternion q to be q * = q 0 + q 1 i + q 2 j − q 3 k. (1) Note that all the star conjugate does is negate the k term. We can easily represent this in terms of the quaternion conjugate, q * = (−k)qk. (2) One may easily show that for any q, v ∈ H, (q *) * = q, |q * | = |q|, (qv) * = v * q *. (3) We now define a mapping between the quaternion algebra to take advantage of the star conjugate. Consider the mapping, q → x = qq *. (4) Immediately we notice, x * = (qq *) * = (q *) * q * = qq * = x, (5) which implies x has the form x = x 0 + x 1 i + x 2 j. (6) To find the values of {x i } 2 0 , we do the quaternion multiplication. The result yields x 0 = q 2 0 − q 2 1 − q 2 2 + q 2 3 x 1 = 2(q 0 q 1 − q 2 q 3) (7) x 2 = 2(q 0 q 2 + q 1 q 3). This is the KS transformation in its classical form. Thus the KS transformation q = (q 0 , q 1 , q 2 , q 3) ∈ R 4 → x = (x 0 , x 1 , x 2) ∈ R 3 is given by the quaternion relation x = qq * , (8) where x = x 0 + x 1 i + x 2 j, q = q 0 + q 1 i + q 2 j + q 3 k, and q * is defined as (1). II. DIFFERENTIATION Since the mapping (4) involving the star conjugate maps from four dimensions to three, we are left with one degree of freedom. We take advantage of this by simplifying differentiation. To do this we impose a bilinear relation between a quaternion q and its differential, dq, being q dq * = dq q *. (9) Note (9) has the form of a commutator. The differential of the star conjugate mapping (4) then becomes dx = dq q * + q dq * = 2dq q *. (10) Using these techniques, Waldvogel 2 reduces the spatial Kepler problem to 2u + hu = 0, (11) with the parameter dt = r · dτ, d dτ () = () , (12) where t is time and r is the radius. For later importance, we note the energy integral: − 2 |q | 2 = −µ + rh. (13) III. DERIVING KEPLER'S LAWS In this section, we will derive Kepler's first law in the standard method for regularizing celestial mechanics , then after which we will prove Kepler's second and third laws using new techniques based upon differentiation and integration. A. Kepler's first law We first solve (11) to find the general solution, u = A cos(ωτ) + B sin(ωτ), ω = h 2 , A, B ∈ H. (14)

Papers by Bilal Amin

Sensors

Cardiac wireless implantable medical devices (CWIMD) have brought a paradigm shift in monitoring ... more Cardiac wireless implantable medical devices (CWIMD) have brought a paradigm shift in monitoring and treating various cardiac conditions, including heart failure, arrhythmias, and hypertension. One of the key elements in CWIMD is the implant antenna which uses radio frequency (RF) technology to wirelessly communicate and transmit data to external devices. However, wireless communication with a deeply implanted antenna using RF can be challenging due to the significant loss of electromagnetic (EM) signal at the air–skin interface, and second, due to the propagation and reflection of EM waves from different tissue boundaries. The air–skin interface loss of the EM wave is pronounced due to the absence of a matching medium. This paper investigates the EM propagation losses in the human body and presents a choice of optimal frequency for the design of the cardiac implant antenna and the dielectric properties of the matching medium. First, the dielectric properties of all tissues present ...

Applied Sciences

Time-series features are the characteristics of data periodically collected over time. The calcul... more Time-series features are the characteristics of data periodically collected over time. The calculation of time-series features helps in understanding the underlying patterns and structure of the data, as well as in visualizing the data. The manual calculation and selection of time-series feature from a large temporal dataset are time-consuming. It requires researchers to consider several signal-processing algorithms and time-series analysis methods to identify and extract meaningful features from the given time-series data. These features are the core of a machine learning-based predictive model and are designed to describe the informative characteristics of the time-series signal. For accurate stress monitoring, it is essential that these features are not only informative but also well-distinguishable and interpretable by the classification models. Recently, a lot of work has been carried out on automating the extraction and selection of times-series features. In this paper, a corr...

Bioengineering

Wireless implantable medical devices (WIMDs) have seen unprecedented progress in the past three d... more Wireless implantable medical devices (WIMDs) have seen unprecedented progress in the past three decades. WIMDs help clinicians in better-understanding diseases and enhance medical treatment by allowing for remote data collection and delivering tailored patient care. The wireless connectivity range between the external reader and the implanted device is considered one of the key design parameters in WIMD technology. One of the common modes of communication in battery-free WIMDs is inductive coupling, where the power and data between the reader and the implanted device are transmitted via magnetically coupled inductors. The design and shape of these inductors depend on the requirements of the application. Several studies have reported models of standard planar inductors such as circular, square, hexagonal, and octagonal in medical applications. However, for applications, constrained by narrow implantable locations, elliptical planar inductors may perform better than standard-shaped pl...

Sensors

The wireless monitoring of key physiological parameters such as heart rate, respiratory rate, tem... more The wireless monitoring of key physiological parameters such as heart rate, respiratory rate, temperature, and pressure can aid in preventive healthcare, early diagnosis, and patient-tailored treatment. In wireless implantable sensors, the distance between the sensor and the reader device is prone to be influenced by the operating frequency, as well as by the medium between the sensor and the reader. This manuscript presents an ex vivo investigation of the wireless linkage between an implantable sensor and an external reader for medical applications. The sensor was designed and fabricated using a cost-effective and accessible fabrication process. The sensor is composed of a circular planar inductor (L) and a circular planar capacitor (C) to form an inductor–capacitor (LC) resonance tank circuit. The reader system comprises a readout coil and data acquisition instrumentation. To investigate the effect of biological medium on wireless linkage, the readout distance between the sensor a...

arXiv (Cornell University), Jul 6, 2021

IEEE Access

The evaluation of the microwave imaging (MWI) prototype and imaging algorithms on experimental bo... more The evaluation of the microwave imaging (MWI) prototype and imaging algorithms on experimental bone phantoms is a precursor step before clinical testing for measuring in vivo dielectric properties of human bones. To this end, this paper presents microwave tomographic image reconstruction of experimental phantoms of normal and diseased human calcaneus bone using an MWI prototype and distorted Born iterative method (DBIM) algorithm for bone health monitoring application. A two-layered simplified cylindrical-shaped 3-D printed phantom was used to mimic the human calcaneus bone. The external and internal layers of the bone phantom mimic the cortical bone and trabecular bone, respectively. Liquid tissue-mimicking mixtures (TMM) for normal bone, osteoporotic bone, and osteoarthritis bone were prepared. The phantoms were placed in the imaging prototype and the electromagnetic inverse scattering problem was solved using the DBIM to create the complex permittivity images. An L 2-based regularization approach was adopted along with the iterative method with adaptive thresholding for compressed sensing (IMATCS) to overcome the ill-posedness and to solve the underdetermined set of linear equations at each DBIM iteration. The reconstruction of dielectric properties of bone phantoms have shown that L 2-IMATCS approach provides a robust reconstruction of diverse bone phantoms with acceptable accuracy. Moreover, the osteoporotic and osteoarthritis bone phantoms were distinguished based on reconstructed dielectric properties with an average percentage difference of 26% at 3 GHz. This paper has made the first attempt to validate an MWI prototype for bone imaging application. A DBIM-based iterative method has been employed to classify normal and diseased bone phantoms. INDEX TERMS Bone health, calcaneus bone phantom, dielectric properties, distorted born iterative method, microwave imaging. BILAL AMIN received the B.S. degree (Hons.

Cambridge University Press eBooks, Oct 1, 2006

This paper examines the sampling and jitter specifications and considerations for Global Navigati... more This paper examines the sampling and jitter specifications and considerations for Global Navigation Satellite Systems (GNSS) software receivers....

Sensors, 2020

Microwave tomography (MWT) can be used as an alternative modality for monitoring human bone healt... more Microwave tomography (MWT) can be used as an alternative modality for monitoring human bone health. Studies have found a significant dielectric contrast between healthy and diseased human trabecular bones. A set of diverse bone phantoms were developed based on single-pole Debye parameters of osteoporotic and osteoarthritis human trabecular bones. The bone phantoms were designed as a two-layered circular structure, where the outer layer mimics the dielectric properties of the cortical bone and the inner layer mimics the dielectric properties of the trabecular bone. The electromagnetic (EM) inverse scattering problem was solved using a distorted Born iterative method (DBIM). A compressed sensing-based linear inversion approach referred to as iterative method with adaptive thresholding for compressed sensing (IMATCS) has been employed for solving the underdetermined set of linear equations at each DBIM iteration. To overcome the challenges posed by the ill-posedness of the EM inverse s...

2018 IEEE 18th International Conference on Nanotechnology (IEEE-NANO), 2018

Computer-aided synthesis benefits from algorithms that are capable of designing compact circuits.... more Computer-aided synthesis benefits from algorithms that are capable of designing compact circuits. This paper is an attempt to improve area and time efficiency of crossbars synthesized using Free Binary Decision Diagrams (FBDDs). We report 13.7% and 6.2% improvement in area and time requirements of multiplier crossbars synthesized using FBDDs. We have used Dynamic Weight Heuristic (DWH) to make FBDDs more compact than the previous approach. Our approach is not multiplier specific; we have found it to perform better than the previous FBDD based synthesis for other RevLib benchmarks as well.

2019 13th European Conference on Antennas and Propagation (EuCAP), 2019

Dielectric properties of bones are proposed to monitor bone quality. However, no study has invest... more Dielectric properties of bones are proposed to monitor bone quality. However, no study has investigated the relationship between bone dielectric properties and microarchitecture of bone, which is of paramount importance for bone quality assessment. This paper reports the first in-vitro investigation of relationship between dielectric properties of human trabecular bone (n = 45) and its microarchitecture parameters (trabecular number, trabecular thickness and trabecular spacing). The objective of the study was to investigate the difference between osteoporotic (n = 23) and osteoarthritis (n = 22) patients in terms of microarchitectural parameters and dielectric properties and to examine any relationship between microarchitectural parameters and dielectric properties. A significant difference was observed between osteoporotic and osteoarthritis patients in terms of microarchitecture parameters. The trabecular number and trabecular thickness were found to be significantly high for oste...

2020 IEEE MTT-S International Microwave Biomedical Conference (IMBioC), 2020

Microwave imaging (MWI) can be used as an alternate imaging modality for monitoring bone health. ... more Microwave imaging (MWI) can be used as an alternate imaging modality for monitoring bone health. Evaluation and characterization of MWI prototype is a precursor step before in vivo investigation of bone dielectric properties. This paper presents experimental evaluation of a novel two layered simplified cylindrical shaped 3D printed human calcaneus bone phantom along with corresponding MWI prototype designed to image the bone phantom. The shape of the calcaneus bone was approximated with a cylinder. The external and internal layers represent cortical bone and trabecular bone respectively. Each layer of the phantom was filled with respective liquid tissue mimicking mixture (TMM). A MWI prototype was designed having six microstrip antennas in order to hold calcaneus bone phantom. The bone phantom was placed in the imaging prototype and scattered signals were measured at each antenna. Moreover, the performance of the system was explored by examining microwave measurement sensitivity. Based on the measured scattered signals the map of dielectric properties will be constructed by employing MWI algorithm and will be communicated in our future work. This two layered 3D printed human calcaneus bone phantom and imaging prototype can be used as a valuable test platform for pre-clinical assessment of calcaneus bone imaging for monitoring osteoporosis.

2020 14th European Conference on Antennas and Propagation (EuCAP), 2020

Microwave imaging can be used as an alternate modality for monitoring bone health. Dielectrically... more Microwave imaging can be used as an alternate modality for monitoring bone health. Dielectrically accurate, anthropomorphic phantoms play vital role in testing of imaging prototype prior to clinical applications. However, no study to date has proposed cortical and trabecular bone phantoms. This paper presents a multilayered 3D-printed human calcaneus structure. Further, we have proposed liquid based tissue phantoms that mimic the dielectric properties of skin, muscle, cortical bone and trabecular bone. Tissue phantoms are composed of Trition X-100, water and salt. The dielectric properties were measured across 0.5-8.5 GHz. Each layer of the 3D-printed structure was filled with corresponding tissue phantom. The combined average percentage difference between dielectric properties of reference data and proposed tissue phantoms was found to be 2.9% for trabecular bone, 7.3% for cortical bone, 7.1% for muscle, and 8.7% for skin over the full measured frequency band. These tissue phantoms and 3D printed human calcaneus structure can be used as a valuable test platform for microwave diagnostic studies.

2018 EMF-Med 1st World Conference on Biomedical Applications of Electromagnetic Fields (EMF-Med), 2018

Dielectric properties of bones have recently got significant attention to monitor bone quality. T... more Dielectric properties of bones have recently got significant attention to monitor bone quality. This paper reports in-vitro dielectric properties of human trabecular bone samples obtained from osteoporotic and osteoarthritic patients. The measurements were performed by using open-ended coaxial probe technique. The study further focuses on intra-femoral head variation of dielectric properties within two patients, and interdisease comparison of bone dielectric properties between osteoporotic and osteoarthritic patients. The results suggest that dielectric properties significantly vary between different parts of femoral head within each patient and mean relative permittivity of osteoarthritic patient is higher in magnitude when compared to osteoporotic patient. The difference is observed more in relative permittivity profiles of each patient's bone samples than conductivity profiles.

IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology, 2020

Tissue-Mimicking Mixtures and Anthropomorphic Calcaneus Phantom for Bone Imaging Applications Tak... more Tissue-Mimicking Mixtures and Anthropomorphic Calcaneus Phantom for Bone Imaging Applications Take-Home Messages • This work presents tissue-mimicking mixtures to mimic the dielectric properties of skin, muscle, cortical bone, and trabecular bone. • Anatomically realistic phantoms must be considered as preclinical testing of the microwave imaging system. • The tissue-mimicking mixtures and the 3D-printed structures presented in this work can be used as a valuable test platform for a microwave imaging system for bone health monitoring. • The recipe of tissue-mimicking mixtures for cortical bone and trabecular bone is presented separately. • This study has proposed separate tissue-mimicking mixtures for cortical bone and trabecular bone.

Polish Journal of Environmental Studies, 2021

A defect free nano-porous zirconia membrane was fabricated using sol-gel method for the separatio... more A defect free nano-porous zirconia membrane was fabricated using sol-gel method for the separation of H 2 gas from a mixture of H 2 and CO 2. Agglomeration of sol was controlled by releasing hydrolyzing water slowly by the reaction of solvent such as alcohol and acetic acid unlike conventional technique. FE-SEM image of ten times coated membrane showed a uniform zirconia layer of 885 nm thickness, coated on α-Al 2 O 3 support. The membrane had pore size of 6 nm. Membrane was fired at 400, 450, and 500ºC to remove organic content, to estimate the final calcination temperature. XRD study confirmed that the zirconia was transformed into tetragonal phase. The crystallite size (D) was 5.0, 10.13, and 16.28 nm for dried and calcined zirconia powder respectively, at 25, 400 and 500ºC. Scherrer's equation was used to estimate crystallite size. TGA showed that there was no significant loss of mass above 600ºC. Gas permeance of the supported ZrO 2 layers was studied by the development of laboratory scale gas permeation setup. The permeance for H 2 and CO 2 as single component at 300ºC, respectively, was 15.21 × 10 −6 and 2.0 × 10 −6 mol/(m 2 sPa). Permeance of membrane in 75:25 H 2 :CO 2 binary feed mixture was 9.96×10 −6 and 1.21×10 −6 mol/(m 2 sPa), respectively, at 300 °C. The selectivity of hydrogen over CO 2 in ZrO 2 membrane for 75:25 H 2 /CO 2 binary feed mixture was 8.23. These results demonstrated that the membranes offer high potential for purification of hydrogen and carbon dioxide in a mixture at an elevated temperature.

Polish Journal of Environmental Studies, 2020

Improved plant nutrition to get high productivity is under severe influence of human activities d... more Improved plant nutrition to get high productivity is under severe influence of human activities drastically impacting the soil-plant ecosystem. In the scenario of increased global socioeconomic demand for food, the changes in land use systems to gain higher agricultural productivity are disrupting the soil properties as well as the associated soil services. This work investigated the impact of different land use systems on phosphorus (P) and associated soil nutrients including K, Ca and Mg across six different land use systems in Abbottabad, Pakistan. Phosphorous fractions were determined by the modified sequential extraction procedures and the concentration of nutrients was measured by double acid digestion. Results revealed the significant variations across different land use systems for P where different P fractions were found considerably varying in order of HCL>NaOH>NaHCO 3 >H 2 O extractable phosphorus. Interestingly, nutrients were found to be varying from thick forest to cultivated lands. Results demonstrate that the shift from the thick forests to thin forests or arable lands may increase the P losses and ultimately disturb the associated soil-plant nutrient status thus should remain intact to promote the plant productivity in a sustainable way.

Medical Engineering & Physics, 2020

The objective of this study is to determine whether in vitro dielectric properties of human trabe... more The objective of this study is to determine whether in vitro dielectric properties of human trabecular bones, can distinguish between osteoporotic and osteoarthritis patients' bone samples. Specifically this study enlightens intra-patient variation of trabecular bone microarchitecture and dielectric properties, inter-disease comparison of bone dielectric properties, and finally establishes the correlation to traditional bone histomorphometry parameter (bone volume fraction) for diseased bone tissue. Bone cores were obtained from osteoporotic and osteoarthritis patients (n = 12). These were scanned using microCT to examine bone volume fraction. An open-ended coaxial probe measurement technique was employed to measure dielectric properties over the 0.5-8.5 GHz frequency range. The dielectric properties of osteoarthritis patients are significantly higher than osteoporotic patients; with an increase of 41% and 45% for relative permittivity and conductivity respectively. The dielectric properties within each patient vary significantly, variation in relative permittivity and conductivity was found to be greater than 25% and 1.4% respectively. A weak correlation (r = 0.5) is observed between relative permittivity and bone volume fraction. Osteoporotic and osteoarthritis bones can be differentiated based on difference of dielectric properties. Although these do not correlate strongly to bone volume fraction, it should be noted that bone volume fraction is a poor predictor of fracture risk. The dielectric properties of bones are found to be influenced by mineralization levels of bones. Therefore, dielectric properties of bones may have potential as a diagnostic measure of osteoporosis.

Medical & biological engineering & computing, Jan 29, 2018

Osteoporosis is one of the most common diseases that leads to bone fractures. Dual-energy X-ray a... more Osteoporosis is one of the most common diseases that leads to bone fractures. Dual-energy X-ray absorptiometry is currently employed to measure the bone mineral density and to diagnose osteoporosis. Alternatively, the dielectric properties of bones are found to be influenced by bone mineral density; hence, dielectric properties of bones may potentially be used to diagnose osteoporosis. Microwave tomographic imaging is currently in development to potentially measure in vivo dielectric properties of bone. Therefore, the foci of this work are to summarize all available dielectric data of bone in the microwave frequency range and to analyze the confounders that may have resulted in variations in reported data. This study also compares the relationship between the dielectric properties and bone quality reported across different studies. The review suggests that variations exist in the dielectric properties of bone and the relationship between bone volume fraction and dielectric propertie...

Biomedical Physics & Engineering Express, 2018

The dielectric properties are key parameters that quantify the interaction between electromagneti... more The dielectric properties are key parameters that quantify the interaction between electromagnetic waves and human biological tissues. In particular, the development of electromagnetic-based medical technologies rely on knowledge of the dielectric properties of bone, specifically for applications such as electrical stimulation and bone health monitoring. Electrical stimulation is used in clinics to promote the healing of bone fractures, treating non-unions, congenital pseudarthrosis, bone regeneration and during bone implant procedures. The response of the bone to any external electrical stimulation is governed by the dielectric properties of the bone, which vary with the applied frequency of the stimuli. Bone mineral density is considered a key indicator of osteoporosis diagnosis, and is assumed to be related to the dielectric properties of the bone. Therefore, dielectric properties of bones may potentially be used to diagnose osteoporosis. The bone dielectric properties can be assessed non-invasively for bone health monitoring. Several research studies have reported dielectric properties of cortical and trabecular bones in recent literature. Since dielectric properties of bone determine the response of the tissue to therapies, it is important to compile and analyze the reported dielectric data in order to have a thorough understanding of these properties. It is established from the literature that the low frequency (10 Hz-1 GHz) dielectric properties of bone are particularly important in diagnostic applications, as the correlation between the dielectric properties and bone mineral density is more significant than at higher frequencies. In this paper, the low frequency dielectric properties of the bone reported in the literature are compiled and quantitatively analysed. The results suggest that there is a significant inter-and intra-species variation in the reported dielectric data from human, bovine, porcine, and rat bone tissues. Moreover, the relationship between the dielectric properties and bone mineral density is inconsistent across the various studies, indicating that further research in this area is needed.

kepler by Quaternionn, 2018

Sensors

Applied Sciences

Bioengineering

Sensors

arXiv (Cornell University), Jul 6, 2021

IEEE Access

Cambridge University Press eBooks, Oct 1, 2006

Sensors, 2020

2018 IEEE 18th International Conference on Nanotechnology (IEEE-NANO), 2018

2019 13th European Conference on Antennas and Propagation (EuCAP), 2019

2020 IEEE MTT-S International Microwave Biomedical Conference (IMBioC), 2020

2020 14th European Conference on Antennas and Propagation (EuCAP), 2020

2018 EMF-Med 1st World Conference on Biomedical Applications of Electromagnetic Fields (EMF-Med), 2018

IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology, 2020

Polish Journal of Environmental Studies, 2021

Polish Journal of Environmental Studies, 2020

Medical Engineering & Physics, 2020

Medical & biological engineering & computing, Jan 29, 2018

Biomedical Physics & Engineering Express, 2018

2016 International Conference on Emerging Technologies (ICET), 2016

Canards are basically horizontal tail installed ahead of centre of gravity which makes aircraft t... more Canards are basically horizontal tail installed ahead of centre of gravity which makes aircraft to pitch up or pitch down with the help of moving parts of canard surface. In canards, configuration point of lift on the wing is behind the centre of gravity of the aircraft. To adjust the characteristic nose down inclination, the canard produces an upward lifting power which opposes weight. It also makes airplane unstable if wind gust increases its angle of attack. In some cases wing lift occurs because of increase in angle of attack. In this work an analytical method has been used to evaluate the pitch damping coefficient for the canard surface of an aircraft. The method is appropriate for a typical aircraft with canard surface. This expression is extracted out by evaluating the moment added to the pitching moment because of the change in the lift of the canard surface. No estimations of physical parameters were useful on the grounds that the primary objective is to find out the expression. The results show that the damping ability is similar as that of the tail. The significance of this particular work is to develop an expression for damping coefficient. The pitch rate causes effective increase in wing angle of the attack resulting in more lift. If the canard's lift is greater than the wing, the nose will pitch further up and hence longitudinal stability of aircraft is more than steady flight condition.