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PublicationImplementation of particle swarm optimization based ICF technique to reduce the PAPR of ACO-OFDM(Walter de Gruyter GmbH, 2023)Orthogonal frequency division multiplexing (OFDM) is advantageous in terms of the spectral efficiency it offers. However, in OFDM, the bandwidth-efficient multicarrier modulation (MM) is limited by the peak-to-average power (PAPR) problem. Iterative clipping and filtering (ICF) method has been used in this work to address such issue. The ICF is regarded as a practical scheme that has become widely accepted and used due to the fact that it is characterized by low computational complexity. This method is also easily implemented, characterized by non-expansion of bandwidth, and it does not require the support to the receiver side during implementation. Nevertheless, the significant of this work is on further improvement where the method involves the iterative clipping of the same signals with a fixed clipping threshold (CT) in every clipping operation. Particle swarm optimization based ICF-OFDM, which is proposed in this research work, literally finds the most suitable clipping ratio, that eventually solves the problem of output power instability. Subsequently, the proposed method is implemented with asymmetrical clipped optical OFDM (ACO-OFDM) to validate the proposed method through the use of Matlab simulation. The PAPR reduction of the proposed method is then compared with the PAPR of the Hartley transform (DHT)-based ACO-OFDM and the traditional ACO-OFDM and DCO-OFDM. The best BER performance has been investigated via two modulation index. Results indicate that our method outperforms the counterparts in term of PAPR reduction and BER performance.
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PublicationSimulation of low-frequency sonophoretic piezoelectric transducer applied over human skin(MDPI Publishing, 2023)Sonophoresis is the process that involves the passage of drug molecules through the skin under ultrasonic stimulation. Drugs with a molecular weight greater than 500 daltons require some kind of stimulus to catalyze their penetration into the skin. Low-frequency sonophoresis, i.e., applying low-frequency (20–100 kHz) ultrasonic waves, is one of the active methods of stimulation used in transdermal drug delivery. The aim of this research is to explore the possibility of achieving high enough acoustic pressures inside human skin using a single-element piezoelectric transducer required to realize the transdermal delivery of drugs with a high molecular weight. Therefore, this paper presents a design and simulation of a single-element transducer to find voltage versus sound pressure levels (SPLs), as well as frequency response curves for low-frequency sonophoresis on human skin. A piezoelectric transducer composed of PZT-5H placed over human skin was simulated by combining the pressure acoustic module, solid mechanics, and electrostatic modules of the simulation tool. The presented simulation applies sinusoidal excitation to a PZT-5H-based transducer. The peak voltage and the frequency of the input are varied to study the resulting variations in acoustic pressure and SPL inside the human skin. Measurements of acoustic pressure are taken 0.1 mm deep into the human skin. The peak acoustic pressure increases linearly from 0.072 Pa to 0.72 Pa as the peak applied voltage increases from 1 mV to 10 mV. The peak acoustic pressure increases exponentially from 0.2 mPa to 5 mPa as the frequency varies from 20 kHz to 100 kHz for a constant peak voltage of 1 mV. The SPL achieved at 880 kHz is 186 dB, which is suitable for drug delivery in some areas of medicine, such as ophthalmology.
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PublicationGlobal, regional, and national mortality of Larynx cancer from 1990 to 2021: results from the global burden of disease study(Springer, 2025-03)Background: Larynx cancer, a major upper respiratory tract malignancy, remains a global public health challenge, driven by smoking, alcohol use, and chronic inflammation, despite medical and public health advancements. Methods: Data from the Global Burden of Disease 2021 study were used to assess larynx cancer mortality trends from 1990 to 2021 across global, regional, and national levels. Death rates, absolute mortality numbers, and Estimated Annual Percentage Change (EAPC) were calculated. Results: Globally, the number of deaths from larynx cancer increased by 36.67% between 1990 and 2021, while death rates slightly declined, with an EAPC of -0.41. Males consistently accounted for the majority of deaths, with 100,393 deaths in 2021, though female mortality showed a larger percentage increase of 60.13% compared to 33.39% in males. Significant regional disparities were evident, with the highest death rates reported in Eastern Europe and Central Latin America, where countries like Bulgaria and Cuba recorded rates exceeding 6 per 100,000 population. In contrast, Oceania reported the lowest rates, below 0.5 per 100,000. The elderly (75 + years) experienced the largest increase in mortality, rising by 85.4%, while deaths among the 15–49 age group remained relatively stable. Additionally, larynx cancer death rates were correlated with SDI. Conclusion: Despite slight declines in global death rates, the absolute burden of larynx cancer has increased due to population growth and aging. Regional disparities emphasize the need for targeted interventions and improved healthcare access. This study offers valuable insights for policy and resource planning.
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PublicationThe current challenges review of deep learning-based nuclei segmentation of diffuse large b-Cell Lymphoma(Science and Information Organization, 2025)Diffuse Large B-Cell Lymphoma stands as the most prevalent form of non-Hodgkin lymphoma worldwide, constituting approximately 30 percent of cases within this diverse group of blood cancers affecting the lymphatic system. This study addresses the challenges associated with the accurate DLBCL segmentation and classification, including difficulties in identifying and diagnosing DLBCL, manpower shortage, and limitations of manual imaging methods. The study highlights the potential of deep learning to effectively segment and classify DLBCL types. The implementation of such technology has the potential to extract and preprocess image patches, identify, and segment the nuclei in DLBCL images, and classify DLBCL severity based on segmented nuclei counting.
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PublicationFeasibility analysis of indoor 3D localization system with UWB using least squares trilateration(Iran University of Science and Technology, 2025-06)Accurate 3D Localization is very important for a wide range of applications, such as indoor navigation, industrial robotics, and motion tracking. This research focuses on indoor 3D positioning systems using ultra-wideband (UWB) devices. Two localization experiments were conducted using the Least Squares Trilateration method. In the first experiment, anchors were at the same height, while in the second, they were at varying heights. The lowest percentage errors in the first experiment were 0% at the x-axis, 0.21% at the y-axis, and 19.75% at the z-axis. In the second experiment, the lowest percentage errors in the experiment were 1.98% at the x-axis, 0.68% at the y-axis, and 17.86% at the z-axis, demonstrating improved accuracy with varied anchor heights at the axis. This work shows the z-axis measurements are unreliable and noisy due to the limited intersection of signal waves of each anchor in a same height anchors setup.