Search results for: resonance topology
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1012

Search results for: resonance topology

442 Photocatalytic Degradation of Methyl Orange by Ag Doped La₂Ti₂O₇

Authors: Hong Zhang

Abstract:

Photocatalytic degradation is an appealing process to remove organic contaminants from industrial wastewater, but usually impeded by less effective photocatalysts. Here, we successfully synthesized Ag doped La₂Ti₂O₇ via a simple sol-gel route for photocatalytic methyl orange (MO) degradation. Their crystal structures, morphology, surface area and optical absorption activity were systematically characterized by X-ray diffraction, scanning electron microscope, BET N₂ adsorption-desorption study, and UV-vis diffuse reflectance spectra. The photocatalytic activity was evaluated by MO photodegradation under a 300 W xenon lamp. The results indicate that the doping of Ag has effectively narrowed the band gap, increased the specific area of La2Ti2O7, and supressed the recombination of photogenerated carriers. Compared with the pristine La₂Ti₂O₇, La₁.₉Ag₀.₁Ti₂O₇-δ revealed a superior performance for MO degradation with a degradation rate of 97% in only 60 min. Also, the pseudo-first order kinetic constant for La₁.₉Ag₀.₁Ti₂O₇-δ is ~ 11 times higher than that of undoped sample. The outstanding performance of Ag modified La₂Ti₂O₇ is probably attributed to the integrated factors. Active species trapping experiments indicated that h+ plays a critical role in MO degradation, while •O₂− has slight effect on the photocatalytic activity and the function of •OH can almost be neglected.

Keywords: Ag doped La₂Ti₂O₇, methyl orange, photodegradation, surface plasmon resonance

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441 Design and Analysis of Metamaterial Based Vertical Cavity Surface Emitting Laser

Authors: Ishraq M. Anjum

Abstract:

Distributed Bragg reflectors are used in vertical-cavity surface-emitting lasers (VCSELs) in order to achieve very high reflectivity. Use of metamaterial in place of distributed Bragg reflector can reduce the device size significantly. A silicon-based metamaterial near perfect reflector is designed to be used in place of distributed Bragg reflectors in VCSELs. Mie resonance in dielectric microparticles is exploited in order to design the metamaterial. A reflectivity of 98.31% is achieved using finite-difference time-domain method. An 808nm double intra-cavity contacted VCSEL structure with 1.5 λ cavity is proposed using this metamaterial near perfect reflector. The active region is designed to be composed of seven GaAs/AlGaAs quantum wells. Upon numerical investigation of the designed VCSEL structure, the threshold current is found to be 2.96 mA at an aperture of 40 square micrometers and the maximum output power is found to be 71 mW at a current of 141 mA. Miniaturization of conventional VCSELs is possible using this design.

Keywords: GaAs, LASER, metamaterial, VCSEL, vertical cavity surface emitting laser

Procedia PDF Downloads 182
440 Anion Exchange Nanocomposite Membrane Doped with ZnO-Nanoparticles for Direct Methanol Alkaline Fuel Cell

Authors: Phumlani Msomi, Patrick Nonjola, Patrick Ndungu, James Ramontja

Abstract:

A series of quaternized poly (2.6 dimethyl – 1.4 phenylene oxide)/ polysulfone (QPPO/PSF) blend anion exchange membrane (AEM) were successfully fabricated and characterized for methanol alkaline fuel cell application. Zinc Oxide (ZnO) nanoparticles were introduced in the polymer matrix to enhance the intrinsic properties of the AEM. To confirm successful fabrication, FT-IR spectroscopy and nuclear magnetic resonance (¹H NMR and HMBC ¹⁵N NMR) were used. The membrane properties were enhanced by the addition of ZnO nanoparticles. The addition of ZnO nanoparticles resulted to a higher ion exchange capacity (IEC) of 3.72 mmol.g⁻¹and a 30-fold ion conductivity (IC) increase of the nanocomposite due to no (zero (0)) methanol permeability at 30 °C and increased water uptake. The QPPO/PSF/2% ZnO composite retained over 80 % of its initial IC when evaluated for alkaline stability at room temperature. The maximum power output reached for the membrane electrode assembly (MEA) constructed with QPPO/PSF/2%ZnO is 69 mW.cm⁻², which is about three times more than the parent QPPO membrane. The above results indicate that QPPO/PSF-ZnO is a good candidate as an anion exchange membrane for fuel cell application.

Keywords: anion exchange membrane, fuel cell, zinc oxide, nanocomposite

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439 Peg@GDF3:TB3+ – Rb Nanocomposites for Deep-Seated X-Ray Induced Photodynamic Therapy in Oncology

Authors: E.A. Kuchma

Abstract:

Photodynamic therapy (PDT) is considered an alternative and minimally invasive cancer treatment modality compared to chemotherapy and radiation therapy. PDT includes three main components: a photosensitizer (PS), oxygen, and a light source. PS is injected into the patient's body and then selectively accumulates in the tumor. However, the light used in PDT (spectral range 400–700 nm) is limited to superficial lesions, and the light penetration depth does not exceed a few cm. The problem of PDT (poor visible light transmission) can be solved by using X-rays. The penetration depth of X-rays is ten times greater than that of visible light. Therefore, X-ray radiation easily penetrates through the tissues of the body. The aim of this work is to develop universal nanocomposites for X-ray photodynamic therapy of deep and superficial tumors using scintillation nanoparticles of gadolinium fluoride (GdF3), doped with Tb3+, coated with a biocompatible coating (PEG) and photosensitizer RB (Rose Bengal). PEG@GdF3:Tb3+(15%) – RB could be used as an effective X-ray, UV, and photoluminescent mediator to excite a photosensitizer for generating reactive oxygen species (ROS) to kill tumor cells via photodynamic therapy. GdF3 nanoparticles can also be used as contrast agents for computed tomography (CT) and magnetic resonance imaging (MRI).

Keywords: X-ray induced photodynamic therapy, scintillating nanoparticle, radiosensitizer, photosensitizer

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438 Energy Efficient Clustering with Reliable and Load-Balanced Multipath Routing for Wireless Sensor Networks

Authors: Alamgir Naushad, Ghulam Abbas, Shehzad Ali Shah, Ziaul Haq Abbas

Abstract:

Unlike conventional networks, it is particularly challenging to manage resources efficiently in Wireless Sensor Networks (WSNs) due to their inherent characteristics, such as dynamic network topology and limited bandwidth and battery power. To ensure energy efficiency, this paper presents a routing protocol for WSNs, namely, Enhanced Hybrid Multipath Routing (EHMR), which employs hierarchical clustering and proposes a next hop selection mechanism between nodes according to a maximum residual energy metric together with a minimum hop count. Load-balancing of data traffic over multiple paths is achieved for a better packet delivery ratio and low latency rate. Reliability is ensured in terms of higher data rate and lower end-to-end delay. EHMR also enhances the fast-failure recovery mechanism to recover a failed path. Simulation results demonstrate that EHMR achieves a higher packet delivery ratio, reduced energy consumption per-packet delivery, lower end-to-end latency, and reduced effect of data rate on packet delivery ratio when compared with eminent WSN routing protocols.

Keywords: energy efficiency, load-balancing, hierarchical clustering, multipath routing, wireless sensor networks

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437 Analysis and Design of Dual-Polarization Antennas for Wireless Communication Systems

Authors: Vladimir Veremey

Abstract:

The paper describes the design and simulation of dual-polarization antennas that use the resonance and radiating properties of the H00 mode of metal open waveguides. The proposed antennas are formed by two orthogonal slots in a finite conducting ground plane. The slots are backed by metal screens connected to the ground plane forming open waveguides. It has been shown that the antenna designs can be efficiently used in mm-wave bands. The antenna single mode operational bandwidth is higher than 10%. The antenna designs are very simple and low-cost. They allow flush installation and can be efficiently used in various communication and remote sensing devices on fast moving carriers. Mutual coupling between antennas of the proposed design is very low. Thus, multiple antenna structures with proposed antennas can be efficiently employed in multi-band and in multiple-input-multiple-output (MIMO) systems.

Keywords: antenna, antenna arrays, Multiple-Input-Multiple-Output (MIMO), millimeter wave bands, slot antenna, flush installation, directivity, open waveguide, conformal antennas

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436 A Rare Case of Dissection of Cervical Portion of Internal Carotid Artery, Diagnosed Postpartum

Authors: Bidisha Chatterjee, Sonal Grover, Rekha Gurung

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Postpartum dissection of the internal carotid artery is a relatively rare condition and is considered as an underlying aetiology in 5% to 25% of strokes under the age of 30 to 45 years. However, 86% of these cases recover completely and 14% have mild focal neurological symptoms. Prognosis is generally good with early intervention. The risk quoted for a repeat carotid artery dissection in subsequent pregnancies is less than 2%. 36-year Caucasian primipara presented on postnatal day one of forceps delivery with tachycardia. In the intrapartum period she had a history of prolonged rupture of membranes and developed intrapartum sepsis and was treated with antibiotics. Postpartum ECG showed septal inferior T wave inversion and a troponin level of 19. Subsequently Echocardiogram ruled out post-partum cardiomyopathy. Repeat ECG showed improvement of the previous changes and in the absence of symptoms no intervention was warranted. On day 4 post-delivery, she had developed symptoms of droopy right eyelid, pain around the right eye and itching in the right ear. On examination, she had developed right sided ptosis, unequal pupils (Rt miotic pupil). Cranial nerve examination, reflexes, sensory examination and muscle power was normal. Apart from migraine, there was no medical or family history of note. In view of Horner’s on the right, she had a CT Angiogram and subsequently MR/MRA and was diagnosed with dissection of the cervical portion of the right internal carotid artery. She was discharged on a course of Aspirin 75mg. By 6 week post-natal follow up patient had recovered significantly with occasional episodes of unequal pupils and tingling of right toes which resolved spontaneously. Cervical artery dissection, including VAD and carotid artery dissection, are rare complications of pregnancy with an estimated annual incidence of 2.6–3 per 100,000 pregnancy hospitalizations. Aetiology remains unclear though trauma during straining at labour, underlying arterial disease and preeclampsia have been implicated. Hypercoagulable state during pregnancy and puerperium could also be an important factor. 60-90% cases present with severe headache and neck pain and generally precede neurological symptoms like ipsilateral Horner’s syndrome, retroorbital pain, tinnitus and cranial nerve palsy. Although rare, the consequences of delayed diagnosis and management can lead to severe and permanent neurological deficits. Patients with a strong index of suspicion should undergo an MRI or MRA of head and neck. Antithrombotic and antiplatelet therapy forms the mainstay of therapy with selected cases needing endovascular stenting. Long term prognosis is favourable with either complete resolution or minimal deficit if treatment is prompt. Patients should be counselled about the recurrence risk and possibility of stroke in future pregnancy. Coronary artery dissection is rare and treatable but needs early diagnosis and treatment. Post-partum headache and neck pain with neurological symptoms should prompt urgent imaging followed by antithrombotic and /or antiplatelet therapy. Most cases resolve completely or with minimal sequelae.

Keywords: postpartum, dissection of internal carotid artery, magnetic resonance angiogram, magnetic resonance imaging, antiplatelet, antithrombotic

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435 Deep Reinforcement Learning Model for Autonomous Driving

Authors: Boumaraf Malak

Abstract:

The development of intelligent transportation systems (ITS) and artificial intelligence (AI) are spurring us to pave the way for the widespread adoption of autonomous vehicles (AVs). This is open again opportunities for smart roads, smart traffic safety, and mobility comfort. A highly intelligent decision-making system is essential for autonomous driving around dense, dynamic objects. It must be able to handle complex road geometry and topology, as well as complex multiagent interactions, and closely follow higher-level commands such as routing information. Autonomous vehicles have become a very hot research topic in recent years due to their significant ability to reduce traffic accidents and personal injuries. Using new artificial intelligence-based technologies handles important functions in scene understanding, motion planning, decision making, vehicle control, social behavior, and communication for AV. This paper focuses only on deep reinforcement learning-based methods; it does not include traditional (flat) planar techniques, which have been the subject of extensive research in the past because reinforcement learning (RL) has become a powerful learning framework now capable of learning complex policies in high dimensional environments. The DRL algorithm used so far found solutions to the four main problems of autonomous driving; in our paper, we highlight the challenges and point to possible future research directions.

Keywords: deep reinforcement learning, autonomous driving, deep deterministic policy gradient, deep Q-learning

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434 Urban Spatial Experience Construction Strategies Under the Intervention of Online Media: A Case Study of Liziba Light Rail Station in Chongqing

Authors: Zhongde Wang, Fanwei Meng, Ling Yang

Abstract:

Today, social media deeply engages in urban spatial production in a ‘Disembedding’ form, allowing the public to ‘foresight’ physical spaces through online platforms and subsequently engage in corresponding ‘sight’ and visits, thus leading to the emergence of ‘Internet Celebrity Spots’. This paper delves into the laws of action of online media, focusing on experiences. From the perspectives of the public, space, and media, it thoroughly analyzes the experiential design strategies of Chongqing's Liziba Light Rail Station, including the construction of the experiential mainline capturing the matrix of public behavior, the creation of experiential sidelines leveraging spatial advantages, and the deepening of experiential touchpoints to promote media resonance. This analysis aims to provide insights and references for similar urban spaces to transition from ‘internet-famous’ to ‘real-famous’ attractions.

Keywords: online media, urban space, disembedding, internet celebrity spots, experience design

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433 Manufacturing an Eminent Mucolytic Medicine Using an Efficient Synthesis Path

Authors: Farzaneh Ziaee, Mohammad Ziaee

Abstract:

N-acetyl-L-cysteine (NAC) is a well-known mucolytic agent, and recently its efficacy has been examined for the prevention and remediation of several diseases such as lung infections caused by Coronavirus. Also, it is administrated as the main antidote in paracetamol overdose and is effective for the treatment of idiopathic pulmonary fibrosis (IPF), chronic obstructive pulmonary disease (COPD). This medicine is used as an antioxidant to prevent diabetic kidney disease (nephropathy). In this study, a method for the acylation of amino acids is employed to manufacture this drug in a height yield. Regarding this patented path, NAC can be made in a single batch step at ambient pressure and temperature. Moreover, this study offers a technique to make peptide bonds which is of interest for pharmaceutical and medicinal industries. The separation process was undertaken using appropriate solvents to achieve an excellent purification level. The synthesized drug was characterized via proton nuclear magnetic resonance (1H NMR), high-performance liquid chromatography (HPLC), Fourier transform infrared spectroscopy (FT-IR), elemental analysis, and melting point.

Keywords: N-acetylcysteine, synthesis, mucolytic medication, lung anti-inflammatory, COVID-19, antioxidant, pharmaceutical supplement, characterization

Procedia PDF Downloads 191
432 Stromal Vascular Fraction Regenerative Potential in a Muscle Ischemia/Reperfusion Injury Mouse Model

Authors: Anita Conti, Riccardo Ossanna, Lindsey A. Quintero, Giamaica Conti, Andrea Sbarbati

Abstract:

Ischemia/reperfusion (IR) injury induces muscle fiber atrophy and skeletal muscle fiber death with subsequently functionality loss. The heterogeneous pool of cells, especially mesenchymal stem cells, contained in the stromal vascular fraction (SVF) of adipose tissue could promote muscle fiber regeneration. To prevent SVF dispersion, it has been proposed the use of injectable biopolymers that work as cells carrier. A significant element of the extracellular matrix is hyaluronic acid (HA), which has been widely used in regenerative medicine as a cell scaffold given its biocompatibility, degradability, and the possibility of chemical functionalization. Connective tissue micro-fragments enriched with SVF obtained from mechanical disaggregation of adipose tissue were evaluated for IR muscle injury regeneration using low molecular weight HA as a scaffold. IR induction. Hindlimb ischemia was induced in 9 athymic nude mice through the clamping of the right quadriceps using a plastic band. Reperfusion was induced by cutting the plastic band after 3 hours of ischemic period. Contralateral (left) muscular tissue was used as healthy control. Treatment. Twenty-four hours after the IR induction, animals (n=3) were intramuscularly injected with 100 µl of SVF mixed with HA (SVF-HA). Animals treated with 100 µl of HA (n=3) and 100 µl saline solution (n=3) were used as control. Treatment monitoring. All animals were in vivo monitored by magnetic resonance imaging (MRI) at 5, 7, 14 and 18 days post-injury (dpi). High-resolution morphological T2 weighed, quantitative T2 map and Dynamic Contrast-Enhanced (DCE) images were acquired in order to assess the regenerative potential of SVF-HA treatment. Ex vivo evaluation. After 18 days from IR induction, animals were sacrificed, and the muscles were harvested for histological examination. At 5 dpi T2 high-resolution MR images clearly reveal the presence of an extensive edematous area due to IR damage for all groups identifiable as an increase of signal intensity (SI) of muscular and surrounding tissue. At 7 dpi, animals of the SVF-HA group showed a reduction of SI, and the T2relaxation time of muscle tissue of the HA-SVF group was 29±0.5ms, comparable with the T2relaxation time of contralateral muscular tissue (30±0.7ms). These suggest a reduction of edematous overflow and swelling. The T2relaxation time at 7dpi of HA and saline groups were 84±2ms and 90±5ms, respectively, which remained elevated during the rest of the study. The evaluation of vascular regeneration showed similar results. Indeed, DCE-MRI analysis revealed a complete recovery of muscular tissue perfusion after 14 dpi for the SVF-HA group, while for the saline and HA group, controls remained in a damaged state. Finally, the histological examination of SVF-HA treated animals exhibited well-defined and organized fibers morphology with a lateralized nucleus, similar to contralateral healthy muscular tissue. On the contrary, HA and saline-treated animals presented inflammatory infiltrates, with HA slightly improving the diameter of the fibers and less degenerated tissue. Our findings show that connective tissue micro-fragments enriched with SVF induce higher muscle homeostasis and perfusion restoration in contrast to control groups.

Keywords: ischemia/reperfusion injury, regenerative medicine, resonance imaging, stromal vascular fraction

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431 The Findings EEG-LORETA about Epilepsy

Authors: Leila Maleki, Ahmad Esmali Kooraneh, Hossein Taghi Derakhshi

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Neural activity in the human brain starts from the early stages of prenatal development. This activity or signals generated by the brain are electrical in nature and represent not only the brain function but also the status of the whole body. At the present moment, three methods can record functional and physiological changes within the brain with high temporal resolution of neuronal interactions at the network level: the electroencephalogram (EEG), the magnet oencephalogram (MEG), and functional magnetic resonance imaging (fMRI); each of these has advantages and shortcomings. EEG recording with a large number of electrodes is now feasible in clinical practice. Multichannel EEG recorded from the scalp surface provides a very valuable but indirect information about the source distribution. However, deep electrode measurements yield more reliable information about the source locations، Intracranial recordings and scalp EEG are used with the source imaging techniques to determine the locations and strengths of the epileptic activity. As a source localization method, Low Resolution Electro-Magnetic Tomography (LORETA) is solved for the realistic geometry based on both forward methods, the Boundary Element Method (BEM) and the Finite Difference Method (FDM). In this paper, we review The findings EEG- LORETA about epilepsy.

Keywords: epilepsy, EEG, EEG-LORETA

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430 Power System Modeling for Calculations in Frequency and Steady State Domain

Authors: G. Levacic, A. Zupan

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Application of new technological solutions and installation of new elements into the network requires special attention when investigating its interaction with the existing power system. Special attention needs to be devoted to the occurrence of harmonic resonance. Sources of increasing harmonic penetration could be wind power plants, Flexible Alternating Current Transmission System (FACTS) devices, underground and submarine cable installations etc. Calculation in frequency domain with various software, for example, the software for power systems transients EMTP-RV presents one of the most common ways to obtain the harmonic impedance of the system. Along calculations in frequency domain, such software allows performing of different type of calculations as well as steady-state domain. This paper describes a power system modeling with software EMTP-RV based on data from SCADA/EMS system. The power flow results on 220 kV and 400 kV voltage levels retrieved from EMTP-RV are verified by comparing with power flow results from power transmissions system planning software PSS/E. The determination of the harmonic impedance for the case of remote power plant connection with cable up to 2500 Hz is presented as an example of calculations in frequency domain.

Keywords: power system modeling, frequency domain, steady state, EMTP-RV, PSS/E

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429 Surface Plasmon Resonance Imaging-Based Epigenetic Assay for Blood DNA Post-Traumatic Stress Disorder Biomarkers

Authors: Judy M. Obliosca, Olivia Vest, Sandra Poulos, Kelsi Smith, Tammy Ferguson, Abigail Powers Lott, Alicia K. Smith, Yang Xu, Christopher K. Tison

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Post-Traumatic Stress Disorder (PTSD) is a mental health problem that people may develop after experiencing traumatic events such as combat, natural disasters, and major emotional challenges. Tragically, the number of military personnel with PTSD correlates directly with the number of veterans who attempt suicide, with the highest rate in the Army. Research has shown epigenetic risks in those who are prone to several psychiatric dysfunctions, particularly PTSD. Once initiated in response to trauma, epigenetic alterations in particular, the DNA methylation in the form of 5-methylcytosine (5mC) alters chromatin structure and represses gene expression. Current methods to detect DNA methylation, such as bisulfite-based genomic sequencing techniques, are laborious and have massive analysis workflow while still having high error rates. A faster and simpler detection method of high sensitivity and precision would be useful in a clinical setting to confirm potential PTSD etiologies, prevent other psychiatric disorders, and improve military health. A nano-enhanced Surface Plasmon Resonance imaging (SPRi)-based assay that simultaneously detects site-specific 5mC base (termed as PTSD base) in methylated genes related to PTSD is being developed. The arrays on a sensing chip were first constructed for parallel detection of PTSD bases using synthetic and genomic DNA (gDNA) samples. For the gDNA sample extracted from the whole blood of a PTSD patient, the sample was first digested using specific restriction enzymes, and fragments were denatured to obtain single-stranded methylated target genes (ssDNA). The resulting mixture of ssDNA was then injected into the assay platform, where targets were captured by specific DNA aptamer probes previously immobilized on the surface of a sensing chip. The PTSD bases in targets were detected by anti-5-methylcytosine antibody (anti-5mC), and the resulting signals were then enhanced by the universal nanoenhancer. Preliminary results showed successful detection of a PTSD base in a gDNA sample. Brighter spot images and higher delta values (control-subtracted reflectivity signal) relative to those of the control were observed. We also implemented the in-house surface activation system for detection and developed SPRi disposable chips. Multiplexed PTSD base detection of target methylated genes in blood DNA from PTSD patients of severity conditions (asymptomatic and severe) was conducted. This diagnostic capability being developed is a platform technology, and upon successful implementation for PTSD, it could be reconfigured for the study of a wide variety of neurological disorders such as traumatic brain injury, Alzheimer’s disease, schizophrenia, and Huntington's disease and can be extended to the analyses of other sample matrices such as urine and saliva.

Keywords: epigenetic assay, DNA methylation, PTSD, whole blood, multiplexing

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428 Acoustic Characteristics of Ḫijaiyaḫ Letters Pronunciation by Indonesian Native Speaker

Authors: Romi Hardiyansyah, Raden Sugeng Joko Sarwono, Agus Samsi

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Indonesian people have a mother language but not Arabic. Meanwhile, they must be able to pronounce the Arabic because Islam is the biggest religion in Indonesia. Arabic is composed by ḫijaiyaḫ letters which has its own pronunciation. Sound production process in humans can be divided into three physiological processes, namely: the formation of airflow from the lungs, the change in airflow from the lungs into the sound, and articulation (the modulation/sound setting into a specific sound). Ḫijaiyaḫ letters has its own articulation, some of which seem strange for most people in Indonesia. Those letters come out from the middle and upper throat so that the letters has its own acoustic characteristics. Acoustic characteristics of voice can be observed by source-filter approach that has parameters: pitch, formant, and formant bandwidth. Pitch is the basic tone in every human being. Formant is the resonance frequency of the human voice. Formant bandwidth is the time-width of a formant. After recording the sound from 21 subjects, data is processed by software Praat version 5.3.39. The analysis showed that each pronunciation, syakal (vowel changer), and the place of discharge letters has the same timbre which are determined by third and fourth formant.

Keywords: ḫijaiyaḫ, articulation, pitch, formant, formant bandwidth, timbre

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427 Biosurfactant-Mediated Nanoparticle Synthesis by Bacillus subtilis

Authors: Satya Eswari Jujjavarapu, Swasti Dhagat, Lata Upadhyay, Reecha Sahu

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Silver nanoparticles have a broad range of antimicrobial and antifungal properties ranging from soaps, pastes to sterilization and drug delivery systems. These can be synthesized by physical, chemical and biological methods; biological methods being the most popular owing to their non-toxic nature and reduced energy requirements. Microbial surfactants, produced on the microbial cell surface or excreted extracellularly are an alternative to synthetic surfactants for the production of silver nanoparticles. Hence, they are also called as green molecules. Microbial lipopeptide surfactants (biosurfactant) exhibit anti-tumor and anti-microbial properties and can be used as drug delivery agents. In this study, biosurfactant was synthesized by using a strain of acillus subtilis. The biosurfactant thus produced was analysed by emulsification assay, oil spilling test, and haemolytic test. Biosurfactant-mediated silver nanoparticles were synthesised by microwave irradiation of the culture supernatant and further characterized by UV–vis spectroscopy for a range of 400-600 nm. The UV–vis spectra showed a surface plasmon resonance vibration band at 410 nm corresponding to the peak of silver nanoparticles.

Keywords: biosurfactant, Bacillus subtilis, silver nano particle, lipopeptide

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426 Embedded Acoustic Signal Processing System Using OpenMP Architecture

Authors: Abdelkader Elhanaoui, Mhamed Hadji, Rachid Skouri, Said Agounad

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In this paper, altera de1-SoC FPGA board technology is utilized as a distinguished tool for nondestructive characterization of an aluminum circular cylindrical shell of radius ratio b/a (a: outer radius; b: inner radius). The acoustic backscattered signal processing system has been developed using OpenMP architecture. The design is built in three blocks; it is implemented per functional block, in a heterogeneous Intel-Altera system running under Linux. The useful data to determine the performances of SoC FPGA is computed by the analytical method. The exploitation of SoC FPGA has lead to obtain the backscattering form function and resonance spectra. A0 and S0 modes of propagation in the tube are shown. The findings are then compared to those achieved from the Matlab simulation of analytical method. A good agreement has, therefore, been noted. Moreover, the detailed SoC FPGA-based system has shown that acoustic spectra are performed at up to 5 times faster than the Matlab implementation using almost the same data. This FPGA-based system implementation of processing algorithms is realized with a coefficient of correlation R and absolute error respectively about 0.962 and 5 10⁻⁵.

Keywords: OpenMP, signal processing system, acoustic backscattering, nondestructive characterization, thin tubes

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425 GeneNet: Temporal Graph Data Visualization for Gene Nomenclature and Relationships

Authors: Jake Gonzalez, Tommy Dang

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This paper proposes a temporal graph approach to visualize and analyze the evolution of gene relationships and nomenclature over time. An interactive web-based tool implements this temporal graph, enabling researchers to traverse a timeline and observe coupled dynamics in network topology and naming conventions. Analysis of a real human genomic dataset reveals the emergence of densely interconnected functional modules over time, representing groups of genes involved in key biological processes. For example, the antimicrobial peptide DEFA1A3 shows increased connections to related alpha-defensins involved in infection response. Tracking degree and betweenness centrality shifts over timeline iterations also quantitatively highlight the reprioritization of certain genes’ topological importance as knowledge advances. Examination of the CNR1 gene encoding the cannabinoid receptor CB1 demonstrates changing synonymous relationships and consolidating naming patterns over time, reflecting its unique functional role discovery. The integrated framework interconnecting these topological and nomenclature dynamics provides richer contextual insights compared to isolated analysis methods. Overall, this temporal graph approach enables a more holistic study of knowledge evolution to elucidate complex biology.

Keywords: temporal graph, gene relationships, nomenclature evolution, interactive visualization, biological insights

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424 Artificial Neural Network to Predict the Optimum Performance of Air Conditioners under Environmental Conditions in Saudi Arabia

Authors: Amr Sadek, Abdelrahaman Al-Qahtany, Turkey Salem Al-Qahtany

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In this study, a backpropagation artificial neural network (ANN) model has been used to predict the cooling and heating capacities of air conditioners (AC) under different conditions. Sufficiently large measurement results were obtained from the national energy-efficiency laboratories in Saudi Arabia and were used for the learning process of the ANN model. The parameters affecting the performance of the AC, including temperature, humidity level, specific heat enthalpy indoors and outdoors, and the air volume flow rate of indoor units, have been considered. These parameters were used as inputs for the ANN model, while the cooling and heating capacity values were set as the targets. A backpropagation ANN model with two hidden layers and one output layer could successfully correlate the input parameters with the targets. The characteristics of the ANN model including the input-processing, transfer, neurons-distance, topology, and training functions have been discussed. The performance of the ANN model was monitored over the training epochs and assessed using the mean squared error function. The model was then used to predict the performance of the AC under conditions that were not included in the measurement results. The optimum performance of the AC was also predicted under the different environmental conditions in Saudi Arabia. The uncertainty of the ANN model predictions has been evaluated taking into account the randomness of the data and lack of learning.

Keywords: artificial neural network, uncertainty of model predictions, efficiency of air conditioners, cooling and heating capacities

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423 State Estimator Performance Enhancement: Methods for Identifying Errors in Modelling and Telemetry

Authors: M. Ananthakrishnan, Sunil K Patil, Koti Naveen, Inuganti Hemanth Kumar

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State estimation output of EMS forms the base case for all other advanced applications used in real time by a power system operator. Ensuring tuning of state estimator is a repeated process and cannot be left once a good solution is obtained. This paper attempts to demonstrate methods to improve state estimator solution by identifying incorrect modelling and telemetry inputs to the application. In this work, identification of database topology modelling error by plotting static network using node-to-node connection details is demonstrated with examples. Analytical methods to identify wrong transmission parameters, incorrect limits and mistakes in pseudo load and generator modelling are explained with various cases observed. Further, methods used for active and reactive power tuning using bus summation display, reactive power absorption summary, and transformer tap correction are also described. In a large power system, verifying all network static data and modelling parameter on regular basis is difficult .The proposed tuning methods can be easily used by operators to quickly identify errors to obtain the best possible state estimation performance. This, in turn, can lead to improved decision-support capabilities, ultimately enhancing the safety and reliability of the power grid.

Keywords: active power tuning, database modelling, reactive power, state estimator

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422 Artificial Intelligence for Generative Modelling

Authors: Shryas Bhurat, Aryan Vashistha, Sampreet Dinakar Nayak, Ayush Gupta

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As the technology is advancing more towards high computational resources, there is a paradigm shift in the usage of these resources to optimize the design process. This paper discusses the usage of ‘Generative Design using Artificial Intelligence’ to build better models that adapt the operations like selection, mutation, and crossover to generate results. The human mind thinks of the simplest approach while designing an object, but the intelligence learns from the past & designs the complex optimized CAD Models. Generative Design takes the boundary conditions and comes up with multiple solutions with iterations to come up with a sturdy design with the most optimal parameter that is given, saving huge amounts of time & resources. The new production techniques that are at our disposal allow us to use additive manufacturing, 3D printing, and other innovative manufacturing techniques to save resources and design artistically engineered CAD Models. Also, this paper discusses the Genetic Algorithm, the Non-Domination technique to choose the right results using biomimicry that has evolved for current habitation for millions of years. The computer uses parametric models to generate newer models using an iterative approach & uses cloud computing to store these iterative designs. The later part of the paper compares the topology optimization technology with Generative Design that is previously being used to generate CAD Models. Finally, this paper shows the performance of algorithms and how these algorithms help in designing resource-efficient models.

Keywords: genetic algorithm, bio mimicry, generative modeling, non-dominant techniques

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421 Dual Reconfigurable Antenna Using Capacitive Coupling Slot and Parasitic Square Ring

Authors: M. Abou Al-alaa, H. A. Elsadek, E. A. Abdallah, E. A. Hashish

Abstract:

A square patch antenna with both frequency and polarization reconfigurability is presented. The antenna consists of a square patch with coplanar feed on the ground plane. On the patch side, there is a parasitic square ring that is responsible for changing the antenna polarization. On the ground plane, there is a rectangular slot. By changing of length of this slot, the antenna resonance frequency can be changed. The antenna operates at 1.57 and 2.45 GHz that used in GPS and Bluetooth applications, respectively. The length of the slot in the proposed antenna is 40 mm, and the antenna operates at the lower frequency (1.57 GHz). By using switches in the ground plane the slot length can be adjust to 24 mm, so the antenna operates at upper frequency (2.45 GHz). Two switches are mounted on the parasitic ring at optimized positions. By switching between the different states of these two switches, the proposed antenna operates with linear polarization (LP) and circular polarization (CP) at each operating frequency. The antenna gain at 1.57 and 2.45 GHz are 5.9 and 7.64 dBi, respectively. The antenna is analyzed using the CST Microwave Studio. The proposed antenna was fabricated and measured. Results comparison shows good agreement. The antenna has applications in several wireless communication systems.

Keywords: microstrip patch antenna, reconfigurable antenna, frequency reconfigurability, polarization reconfigurability, parasitic square ring, linear polarization, circular polarization

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420 Minimal Incision Cochlear Implantation in Congenital Abnormality: A Case Report

Authors: Munish Saroch, Amit Saini

Abstract:

Introduction: Many children with congenital malformation of inner ear have undergone cochlear implant (CI) surgery. The results for cochlear implant surgery in these children are very encouraging and provide a ray of hope for these patients. Objective: The main objective of this presentation is to prove that even in Mondini’s deformity Minimal incision cochlear implantation improves cosmesis, reduces post-operative infection and earliest switch on of device. Methods: We report a case of two-year-old child suffering from Mondini’s deformity who underwent CI with minimal incision cochlear implantation (MICI). MICI has been developed with the aims of reducing the impact of surgery on the patient without any preoperative shaving of hairs. Results: Patient after surgery with MICI showed better looking postauricular scar, low post-operative morbidity in comparison to conventional wider access approach and hence earliest switch on of device (1st post operative day). Conclusion: We are of opinion that MICI is safe and successful in Mondini’s deformity.

Keywords: CI, Cochlear Implant, MICI, Minimal Incision Cochlear Implantation, HL, Hearing Loss, HRCT, High Resolution Computer Tomography, MRI, Magnetic resonance imaging, SCI, Standard cochlear implantation

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419 Relationship Between Pain Intensity at the Time of the Hamstring Muscle Injury and Hamstring Muscle Lesion Volume Measured by Magnetic Resonance Imaging

Authors: Grange Sylvain, Plancher Ronan, Reurink Guustav, Croisille Pierre, Edouard Pascal

Abstract:

The primary objective of this study was to analyze the potential correlation between the pain experienced at the time of a hamstring muscle injury and the volume of the lesion measured on MRI. The secondary objectives were to analyze a correlation between this pain and the lesion grade as well as the affected hamstring muscle. We performed a retrospective analysis of the data collected in a prospective, multicenter, non-interventional cohort study (HAMMER). Patients with suspected hamstring muscle injury had an MRI after the injury and at the same time were evaluated for their pain intensity experienced at the time of the injury with a Numerical Pain Rating Scale (NPRS) from 0 to 10. A total of 61 patients were included in the present analysis. MRIs were performed in an average of less than 8 days. There was a significant correlation between pain and the injury volume (r=0.287; p=0.025). There was no significant correlation between the pain and the lesion grade (p>0.05), nor between the pain and affected hamstring muscle (p>0.05). Pain at the time of injury appeared to be correlated with the volume of muscle affected. These results confirm the value of a clinical approach in the initial evaluation of hamstring injuries to better select patients eligible for further imaging.

Keywords: hamstring muscle injury, MRI, volume lesion, pain

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418 Factor Analysis Based on Semantic Differential of the Public Perception of Public Art: A Case Study of the Malaysia National Monument

Authors: Yuhanis Ibrahim, Sung-Pil Lee

Abstract:

This study attempts to address factors that contribute to outline public art factors assessment, memorial monument specifically. Memorial monuments hold significant and rich message whether the intention of the art is to mark and commemorate important event or to inform younger generation about the past. Public monument should relate to the public and raise awareness about the significant issue. Therefore, by investigating the impact of the existing public memorial art will hopefully shed some lights to the upcoming public art projects’ stakeholders to ensure the lucid memorial message is delivered to the public directly. Public is the main actor as public is the fundamental purpose that the art was created. Perception is framed as one of the reliable evaluation tools to assess the public art impact factors. The Malaysia National Monument was selected to be the case study for the investigation. The public’s perceptions were gathered using a questionnaire that involved (n-115) participants to attain keywords, and next Semantical Differential Methodology (SDM) was adopted to evaluate the perceptions about the memorial monument. These perceptions were then measured with Reliability Factor and then were factorised using Factor Analysis of Principal Component Analysis (PCA) method to acquire concise factors for the monument assessment. The result revealed that there are four factors that influence public’s perception on the monument which are aesthetic, audience, topology, and public reception. The study concludes by proposing the factors for public memorial art assessment for the next future public memorial projects especially in Malaysia.

Keywords: factor analysis, public art, public perception, semantical differential methodology

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417 F-VarNet: Fast Variational Network for MRI Reconstruction

Authors: Omer Cahana, Maya Herman, Ofer Levi

Abstract:

Magnetic resonance imaging (MRI) is a long medical scan that stems from a long acquisition time. This length is mainly due to the traditional sampling theorem, which defines a lower boundary for sampling. However, it is still possible to accelerate the scan by using a different approach, such as compress sensing (CS) or parallel imaging (PI). These two complementary methods can be combined to achieve a faster scan with high-fidelity imaging. In order to achieve that, two properties have to exist: i) the signal must be sparse under a known transform domain, ii) the sampling method must be incoherent. In addition, a nonlinear reconstruction algorithm needs to be applied to recover the signal. While the rapid advance in the deep learning (DL) field, which has demonstrated tremendous successes in various computer vision task’s, the field of MRI reconstruction is still in an early stage. In this paper, we present an extension of the state-of-the-art model in MRI reconstruction -VarNet. We utilize VarNet by using dilated convolution in different scales, which extends the receptive field to capture more contextual information. Moreover, we simplified the sensitivity map estimation (SME), for it holds many unnecessary layers for this task. Those improvements have shown significant decreases in computation costs as well as higher accuracy.

Keywords: MRI, deep learning, variational network, computer vision, compress sensing

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416 Numerical and Experimental Investigation of Airflow Inside Car Cabin

Authors: Mokhtar Djeddou, Amine Mehel, Georges Fokoua, Anne Tanière, Patrick Chevrier

Abstract:

Commuters' exposure to air pollution, particularly to particle matter, inside vehicles is a significant health issue. Assessing particles concentrations and characterizing their distribution is an important first step to understand and propose solutions to improve car cabin air quality. It is known that particles dynamics is intimately driven by particles-turbulence interactions. In order to analyze and model pollutants distribution inside the car the cabin, it is crucialto examine first the single-phase flow topology and turbulence characteristics. Within this context, Computational Fluid Dynamics (CFD) simulations were conducted to model airflow inside a full-scale car cabin using Reynolds Averaged Navier-Stokes (RANS)approach combined with the first order Realizable k- εmodel to close the RANS equations. To validate the numerical model, a campaign of velocity field measurements at different locations in the front and back of the car cabin has been carried out using hot-wire anemometry technique. Comparison between numerical and experimental results shows a good agreement of velocity profiles. Additionally, visualization of streamlines shows the formation of jet flow developing out of the dashboard air vents and the formation of large vortex structures, particularly in the back seats compartment. These vortex structures could play a key role in the accumulation and clustering of particles in a turbulent flow

Keywords: car cabin, CFD, hot wire anemometry, vortical flow

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415 Ab Initio Approach to Generate a Binary Bulk Metallic Glass Foam

Authors: Jonathan Galvan-Colin, Ariel Valladares, Renela Valladares, Alexander Valladares

Abstract:

Both porous materials and bulk metallic glasses have been studied due to their potential applications and their exceptional physical and chemical properties. However, each material presents certain drawbacks which have been thought to be overcome by generating bulk metallic glass foams (BMGF). Although some experimental reports have been performed on multicomponent BMGF, still no ab initio works have been published, as far as we know. We present an approach based on the expanding lattice (EL) method to generate binary amorphous nanoporous Cu64Zr36. Starting from two different configurations: a 108-atom crystalline cubic supercell (cCu64Zr36) and a 108-atom amorphous supercell (aCu64Zr36), both with an initial density of 8.06 g/cm3, we applied EL method to halve the density and to get 50% of porosity. After the lattice expansion the supercells were subject to ab initio molecular dynamics for 500 steps at constant room temperature. Then, the samples were geometry-optimized and characterized with the pair and radial distribution functions, bond-angle distributions and a coordination number analysis. We found that pores appeared along specific spatial directions different from one to another and that they differed in size and form as well, which we think is related to the initial structure. Due to the lack of experimental counterparts our results should be considered predictive and further studies are needed in order to handle a larger number of atoms and its implication on pore topology.

Keywords: ab initio molecular dynamics, bulk mettalic glass, porous alloy

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414 The Design and Analysis of a Novel Type High Gain Microstrip Patch Antenna System for the Satellite Communication

Authors: Shahid M. Ali, Zakiullah

Abstract:

An individual feed, smooth and smart, completely new shaped, dual band microstrip patch antenna has been proposed in this manuscript. Right here three triangular shape slots are usually presented in the 3 edges on the patch and along with a small feed line has utilized another edge on the patch to find out the dual band. The antenna carries a condensed framework wherever patch is around about 8.5mm by means of 7.96mm by means of 1.905mm leading to excellent bandwidths covering 13. 15 GHz to 13. 72 GHz in addition to 16.04 GHz to 16.58GHz. The return loss(RL) decrease in -19. 00dB and will be attained in the first resonant frequency at 13. 61 GHz and -28.69dB is at second resonance frequency at 16.33GHz. The stable average peak gain that may be observed along the operating band in lower and higher frequency is actually three. 53dB in addition to 5.562dB correspondingly. The radiation designs usually are omni directional along with moderate gain within equally most of these functioning bands. Accomplishment is proven within double frequencies at 13.62GHz since downlink in addition to 16.33GHz since uplink. This kind of low and simple configuration of the proposed antenna shows simplest fabrication and make it ensure that it is adaptable for your application within instant in satellite and as well as for the wireless communication system.

Keywords: dual band, microstrip patch antenna, HFSS, Ku band, satellite

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413 Phenolic Analysis, Antioxidant Capacity and Antimicrobial Activity of Origanum glandulosum Desf Extract from Algeria

Authors: Abdelkader Basli, Jean-Claude Delaunay, Eric Pedrot, Jean-Michel Mérillon, Jean-Pierre Monti, Khodir Madani, Mohamed Chibane, Tristan Richard

Abstract:

The antioxidant and antimicrobial activities of Origanum glandulosum collected in Algeria have been studied. Extract was prepared from aerial part of endemic Algerian oregano. The produced extract has been characterized in terms of total phenols (using Folin method), total flavonoid, antioxidant activities (using the DPPH radical scavenging method and ORAC assay) and microbial activity against four bacteria: Streptococcus aureus, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae one yeast: Candida albicans and one fungi: Aspergillus niger. The results pointed the antioxidant activities of the extract of O. glandulosum and antimicrobial activities against all bacteria and C. Candida, but no effect on A. niger. High performance liquid chromatography combined with mass spectrometry (LC-MS) and nuclear magnetic resonance (LC-NMR) were used to separate and identify the major compounds present in the oregano extract. Rosmarinic acid, globoidnan A and B, lithospermic acid B and three flavonoids were identified.

Keywords: origanum glandulosum, antioxidant, microbial activity, polyphenol, LC-MS, LC-NMR

Procedia PDF Downloads 645