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27,592 results on '"Hamidi A"'

155. Modeling of Potable Water Purification System by Using III–V Multijunction Solar Cell and Cationic Polyacrylamide Alum to Improve the Efficiency

Author

Shehram, Muhammad, Wahab, Aeizaal Azman A., Rani, Uzma, Hamidi, Muhammad Najwan, Mat Desa, M. K., Chaari, Fakher, Series Editor, Gherardini, Francesco, Series Editor, Ivanov, Vitalii, Series Editor, Haddar, Mohamed, Series Editor, Cavas-Martínez, Francisco, Editorial Board Member, di Mare, Francesca, Editorial Board Member, Kwon, Young W., Editorial Board Member, Tolio, Tullio A. M., Editorial Board Member, Trojanowska, Justyna, Editorial Board Member, Schmitt, Robert, Editorial Board Member, Xu, Jinyang, Editorial Board Member, Hamidon, Roshaliza, editor, Bahari, Muhammad Syahril, editor, Sah, Jamali Md, editor, and Zainal Abidin, Zailani, editor

Published
2024
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156. A New Framework for Amplifying Business Performance of SMEs in Riau Province through Digital Finance and Financial Literacy

Author

Adiya, M. Hasmil, Hamidi, Masyhuri, Rahim, Rida, Adrianto, Fajri, Appolloni, Andrea, Series Editor, Caracciolo, Francesco, Series Editor, Ding, Zhuoqi, Series Editor, Gogas, Periklis, Series Editor, Huang, Gordon, Series Editor, Nartea, Gilbert, Series Editor, Ngo, Thanh, Series Editor, Striełkowski, Wadim, Series Editor, Hurriyati, Ratih, editor, Wibowo, Lili Adi, editor, Sulastri, Sulastri, editor, and Lisnawati, Lisnawati, editor

Published
2024
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157. Formalizing for Proving the System Safety of the Software Component for a Small Sized Guided Transport System

Author

Hamidi, Amine, Collart-Dutilleul, Simon, Bon, Philippe, Goos, Gerhard, Series Editor, Hartmanis, Juris, Founding Editor, van Leeuwen, Jan, Series Editor, Hutchison, David, Editorial Board Member, Kanade, Takeo, Editorial Board Member, Kittler, Josef, Editorial Board Member, Kleinberg, Jon M., Editorial Board Member, Kobsa, Alfred, Series Editor, Mattern, Friedemann, Editorial Board Member, Mitchell, John C., Editorial Board Member, Naor, Moni, Editorial Board Member, Nierstrasz, Oscar, Series Editor, Pandu Rangan, C., Editorial Board Member, Sudan, Madhu, Series Editor, Terzopoulos, Demetri, Editorial Board Member, Tygar, Doug, Editorial Board Member, Weikum, Gerhard, Series Editor, Vardi, Moshe Y, Series Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Woeginger, Gerhard, Editorial Board Member, Ait Wakrime, Abderrahim, editor, Navarro-Arribas, Guillermo, editor, Cuppens, Frédéric, editor, Cuppens, Nora, editor, and Benaini, Redouane, editor

Published
2024
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158. Recommendation System over Multi-layer Complex Networks: A Wide and Deep Graph Convolutional Neural Network Approach

Author

Hamidi Rad, Radin, ZareMehrjerdi, Hossein, Mirmohammad, Yasaman, Shahsavari, Mohammad Navid, Haeri, Maryam Amir, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, and Arai, Kohei, editor

Published
2024
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160. Methodological Comparison and Analysis for Six-Switching PMBLDC Motor Control

Author

Gujja, Musa Mohammed, Ishak, Dahaman, Hamidi, Muhammad Najwan, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Tan, Kay Chen, Series Editor, Ahmad, Nur Syazreen, editor, Mohamad-Saleh, Junita, editor, and Teh, Jiashen, editor

Published
2024
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161. Control Method of Two-Stage Grid-Connected PV Inverter System

Author

Zhe, Wang, Ishak, Dahaman, Hamidi, Muhammad Najwan, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Tan, Kay Chen, Series Editor, Ahmad, Nur Syazreen, editor, Mohamad-Saleh, Junita, editor, and Teh, Jiashen, editor

Published
2024
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162. Modeling of Multijunction Solar Cells InGaAs/InGaP/GaAs/GeSi for Improving the Efficiency of PV Modules by 43%

Author

Shehram, Muhammad, Hamidi, Muhammad Najwan, A.Wahab, Aeizaal Azman, Desa, M. K. Mat, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Tan, Kay Chen, Series Editor, Ahmad, Nur Syazreen, editor, Mohamad-Saleh, Junita, editor, and Teh, Jiashen, editor

Published
2024
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163. Improved DC-Link Voltage Control Scheme for Standalone PV Renewable Energy System

Author

Hamidi, Muhammad Najwan, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Tan, Kay Chen, Series Editor, Ahmad, Nur Syazreen, editor, Mohamad-Saleh, Junita, editor, and Teh, Jiashen, editor

Published
2024
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164. Interactive Topic Tagging in Community Question Answering Platforms

Author

Hamidi Rad, Radin, Cucerzan, Silviu, Chandrasekaran, Nirupama, Gamon, Michael, Goos, Gerhard, Founding Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Goharian, Nazli, editor, Tonellotto, Nicola, editor, He, Yulan, editor, Lipani, Aldo, editor, McDonald, Graham, editor, Macdonald, Craig, editor, and Ounis, Iadh, editor

Published
2024
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165. A Kinetic Test Method to Assess the Long-Term Acid Generation Behavior of Sludge/Slag and Mine Tailings of Mine a (Quebec, Canada)

Author

El Hamidi, Mohamed Jalal, Maqsoud, Abdelkabir, Belem, Tikou, Pisello, Anna Laura, Editorial Board Member, Hawkes, Dean, Editorial Board Member, Bougdah, Hocine, Editorial Board Member, Rosso, Federica, Editorial Board Member, Abdalla, Hassan, Editorial Board Member, Boemi, Sofia-Natalia, Editorial Board Member, Mohareb, Nabil, Editorial Board Member, Mesbah Elkaffas, Saleh, Editorial Board Member, Bozonnet, Emmanuel, Editorial Board Member, Pignatta, Gloria, Editorial Board Member, Mahgoub, Yasser, Editorial Board Member, De Bonis, Luciano, Editorial Board Member, Kostopoulou, Stella, Editorial Board Member, Pradhan, Biswajeet, Editorial Board Member, Abdul Mannan, Md., Editorial Board Member, Alalouch, Chaham, Editorial Board Member, Gawad, Iman O., Editorial Board Member, Nayyar, Anand, Editorial Board Member, Amer, Mourad, Series Editor, Çiner, Attila, editor, Naitza, Stefano, editor, Radwan, Ahmed E., editor, Hamimi, Zakaria, editor, Lucci, Federico, editor, Knight, Jasper, editor, Cucciniello, Ciro, editor, Banerjee, Santanu, editor, Chennaoui, Hasnaa, editor, Doronzo, Domenico M., editor, Candeias, Carla, editor, Rodrigo-Comino, Jesús, editor, Kalatehjari, Roohollah, editor, Shah, Afroz Ahmad, editor, Gentilucci, Matteo, editor, Panagoulia, Dionysia, editor, Chaminé, Helder I., editor, Barbieri, Maurizio, editor, and Ergüler, Zeynal Abiddin, editor

Published
2024
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166. Energy Consumption of Variable Speed Pumps Under Transient-State Condition in Water Distribution Networks

Author

Jamil, Rehan, Aziz, Hamidi Abdul, Murshed, Mohamad Fared, di Prisco, Marco, Series Editor, Chen, Sheng-Hong, Series Editor, Vayas, Ioannis, Series Editor, Kumar Shukla, Sanjay, Series Editor, Sharma, Anuj, Series Editor, Kumar, Nagesh, Series Editor, Wang, Chien Ming, Series Editor, Cui, Zhen-Dong, Series Editor, and Sabtu, Nuridah, editor

Published
2024
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169. Treatment of Palm Oil Mill Effluent

Author

Sabiani, Nor Habsah Md, Alkarimiah, Rosnani, Ayub, Khairul Rahmah, Makhtar, Muaz Mohd Zaini, Aziz, Hamidi Abdul, Hung, Yung-Tse, Wang, Lawrence K., Wang, Mu-Hao Sung, Wang, Lawrence K., Series Editor, Wang, Mu-Hao Sung, Series Editor, Sung Wang, Mu-Hao, editor, and Hung, Yung-Tse, editor

Published
2024
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171. Management of Various Sources of Hazardous Waste

Author

Rosli, Nor Azalina, Aziz, Hamidi Abdul, Pueh, Leonard Lim Lik, Othman, Inawati Binti, Zawawi, Mohd Hafiz, Hung, Yung-Tse, Wang, Lawrence K., Series Editor, Wang, Mu-Hao Sung, Series Editor, Sung Wang, Mu-Hao, editor, and Hung, Yung-Tse, editor

Published
2024
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173. Extraction of Humic Acid Followed by Coagulation with Natural Starch Coagulant for the Elimination of Color and COD from Stabilized Leachate

Author

Ahmed, Zaber, Yusoff, Mohd Suffian, Mokhtar Kamal, N. H., Aziz, Hamidi Abdul, di Prisco, Marco, Series Editor, Chen, Sheng-Hong, Series Editor, Vayas, Ioannis, Series Editor, Kumar Shukla, Sanjay, Series Editor, Sharma, Anuj, Series Editor, Kumar, Nagesh, Series Editor, Wang, Chien Ming, Series Editor, Cui, Zhen-Dong, Series Editor, and Sabtu, Nuridah, editor

Published
2024
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174. Characterisation of Oil Palm (Elaeis guineensis) Trunk Starch as Coagulant for Landfill Leachate Treatment

Author

Mohd Yusoff, Nur Hayati, Yusoff, Mohd Suffian, Aziz, Hamidi Abdul, Ahmed, Zaber, di Prisco, Marco, Series Editor, Chen, Sheng-Hong, Series Editor, Vayas, Ioannis, Series Editor, Kumar Shukla, Sanjay, Series Editor, Sharma, Anuj, Series Editor, Kumar, Nagesh, Series Editor, Wang, Chien Ming, Series Editor, Cui, Zhen-Dong, Series Editor, and Sabtu, Nuridah, editor

Published
2024
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177. The Effectiveness of Silica Sand in Semi-Aerobic Stabilized Landfill Leachate Treatment

Author

Ezlina Othman, Yung-Tse Hung, Mohammed J. K. Bashir, Mohd Nordin Adlan, Hamidi Abdul Aziz, and Mohd Suffian Yusoff

Subjects
semi-aerobic landfill, stabilized leachate treatment, adsorption, silica sand, Hydraulic engineering, TC1-978, Water supply for domestic and industrial purposes, TD201-500
Abstract

This study examines the suitability of natural silica sand as a low-cost adsorbent for the removal of ammoniacal nitrogen and heavy metals, particularly iron and zinc, from semi-aerobic stabilized landfill leachate. Leachate samples were collected from the Pulau Burung landfill site (PBLS) in Penang, Malaysia. The above-mentioned contaminants are highlighted in this study because of their unsafe concentrations at PBLS. The effects of shaking time, settling time, and silica sand dosage on the study parameter removal efficiencies were investigated to predict the performance of the process. The adsorptions of ammoniacal nitrogen, iron, and zinc were judiciously described by Langmuir and Freundlich isotherm models. The optimum removal efficiencies of ammoniacal nitrogen, iron, and zinc obtained were 51%, 44.4%, and 39.2%, respectively, with a shaking time of 90 min, a settling time of 60 min, and with a dosage of 60 g (0.5 kg/L) of silica sand. Based on the coefficient of determination (R2) values obtained from Langmuir and Freundlich isotherm models, ammoniacal nitrogen, iron, and zinc adsorption were better fitted to the Freundlich model.

Published
2010
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178. Potential Use of Dimocarpus longan Seeds as a Flocculant in Landfill Leachate Treatment

Author

Hamidi Abdul Aziz, Nor Aini Rahim, Siti Fatihah Ramli, Motasem Y. D. Alazaiza, Fatehah Mohd Omar, and Yung-Tse Hung

Subjects
Dimocarpus longan seeds, leachate treatment, coagulant–flocculation, polyaluminium chloride, Hydraulic engineering, TC1-978, Water supply for domestic and industrial purposes, TD201-500
Abstract

Landfill leachate is a highly polluted and generated from water infiltration through solid waste produced domestically and industrially. In this study, a coagulation⁻flocculation process using a combination of Polyaluminium chloride (PACl) as a coagulant and Dimocarpus longan seed powder (LSP) as coagulant aid was used in treating landfill leachate. LSP has been tested as the main coagulant and as coagulant aid with PACl. As the main coagulant, the optimum dosage and pH for PACl were 5 g/L and 6, respectively, with removal efficiencies of 67.44%, 99.47%, and 98% for COD, SS, and color, respectively. For LSP as the main coagulant, results show that LSP is not effective where the removal efficiencies obtained for COD, SS, and color were 39.40%, 22.20%, and 28.30%, respectively, with the optimum dosage of 2 g/L and pH 4. The maximum removal efficiencies of COD, SS, and color were 69.19%, 99.50%, and 98.80%, respectively, when LSP was used as coagulant aid with PACl. Results show that using LSP as coagulant aid was found to be more effective in the removal of COD, SS, and color with less PACl dosage. The PACl dosage was decreased from 5 to 2.75 g/L when LSP was used as a coagulant aid. Cost estimation for using PACl alone and using LSP as the coagulant aid showed a reduction in the cost of approximately 40% of the cost of using PACl alone. Overall, this study confirmed the efficiency of LSP to be used as a natural coagulant aid in leachate treatment.

Published
2018
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179. Vandermonde Constrained Tensor Decomposition for Hybrid Beamforming in Multi-Carrier MIMO Systems

Author

Ibrahim, Mohamed Salah, Malhotra, Akshay, Beluri, Mihaela, Roy, Arnab, and Hamidi-Rad, Shahab

Subjects
Electrical Engineering and Systems Science - Signal Processing
Abstract

Hybrid beamforming has evolved as a promising technology that offers the balance between system performance and design complexity in mmWave MIMO systems. Existing hybrid beamforming methods either impose unit-modulus constraints or a codebook constraint on the analog precoders/combiners, which in turn results in a performance-overhead tradeoff. This paper puts forth a tensor framework to handle the wideband hybrid beamforming problem, with Vandermonde constraints on the analog precoders/combiners. The proposed method strikes the balance between performance, overhead and complexity. Numerical results on a 3GPP link-level test bench reveal the efficacy of the proposed approach relative to the codebook-based method while attaining the same feedback overhead. Moreover, the proposed method is shown to achieve comparable performance to the unit-modulus approaches, with substantial reductions in overhead.

Published
2022

180. Challenges in Close-Proximity Safe and Seamless Operation of Manned and Unmanned Aircraft in Shared Airspace

Author

Patrikar, Jay, Dantas, Joao P. A., Ghosh, Sourish, Kapoor, Parv, Higgins, Ian, Aloor, Jasmine J., Navarro, Ingrid, Sun, Jimin, Stoler, Ben, Hamidi, Milad, Baijal, Rohan, Moon, Brady, Oh, Jean, and Scherer, Sebastian

Subjects
Computer Science - Robotics
Abstract

We propose developing an integrated system to keep autonomous unmanned aircraft safely separated and behave as expected in conjunction with manned traffic. The main goal is to achieve safe manned-unmanned vehicle teaming to improve system performance, have each (robot/human) teammate learn from each other in various aircraft operations, and reduce the manning needs of manned aircraft. The proposed system anticipates and reacts to other aircraft using natural language instructions and can serve as a co-pilot or operate entirely autonomously. We point out the main technical challenges where improvements on current state-of-the-art are needed to enable Visual Flight Rules to fully autonomous aerial operations, bringing insights to these critical areas. Furthermore, we present an interactive demonstration in a prototypical scenario with one AI pilot and one human pilot sharing the same terminal airspace, interacting with each other using language, and landing safely on the same runway. We also show a demonstration of a vision-only aircraft detection system.

Published
2022

181. Quasilinear P.D.Es, Interpolation spaces and H\'olderian mappings

Author

Ahmed, Irshaad, Fiorenza, Alberto, Formica, Maria Rosaria, Gogatishvili, Amiran, Hamidi, Abdallah El, and Rakotoson, Jean Michel

Subjects
Mathematics - Analysis of PDEs, Mathematics - Functional Analysis, 35B45, 35D30, 35J25, 46E30, 46B70
Abstract

As in the work of Tartar ( Tartar L. Interpolation non lin\'eaire et r\'egularit\'e, 9, Journal of Functional Analysis, (1972), 469-489) we developed here some new results on non linear interpolation of $\alpha$-H\"olderian mappings between normed spaces, namely, by studying the action of the mappings on $K$-functionals and between interpolation spaces with logarithm functors. We apply those results to obtain regularity results on the gradient of the solution to quasilinear equations of the form $$-div(\widehat a(\nabla u ))+V(u)=f, $$ whenever $V$ is a nonlinear potential, $f$ belongs to non standard spaces as Lorentz-Zygmund spaces. We show among other that the mapping $T: \ Tf=\nabla u$ is locally or globally $\alpha$-H\"olderian under suitable values of $\alpha$ and adequate hypothesis on $V$ and $\widehat a.$

Published
2022

182. Bloch Surface Wave-atom Coupling in Periodic Photonic Structure

Author

Salmanpour, M. Asadolah, Mosleh, M., and Hamidi, S. M.

Subjects
Physics - Atomic Physics
Abstract

Considering efforts for hot atom vapor-nanophotonic integration as a new paradigm in quantum optics in this paper we introduce 1D photonic crystal-Rb vapor cell as structure with miniaturized interaction volume. The Bloch surface wave excited on surface of a photonic crystal as electromagnetic hosting photonic mode, and altered the optical response of Rb atoms in the vicinity of surface. Coupling of atomic states with BSW confined modes would lead to quantum interference effects and results in nonlinearities in resonant coupling of atoms with BSW. We show Bloch surface wave induced transparency is highly stable under a change of incidence angle. Our results show slight changes in transitions detunings due to nonlinear interactions like the Casimir-Polder effect under change of localized density of optical states., Comment: 15 pages, 4 figures

Published
2022
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183. Decoding Polar Codes via Noisy Quantum Gates: Quantum Circuits and Insights

Author

Kasi, Srikar, Kaewell, John, Hamidi-Rad, Shahab, and Jamieson, Kyle

Subjects
Computer Science - Networking and Internet Architecture, Quantum Physics
Abstract

The use of quantum computation for wireless network applications is emerging as a promising paradigm to bridge the performance gap between in-practice and optimal wireless algorithms. While today's quantum technology offers limited number of qubits and low fidelity gates, application-based quantum solutions help us to understand and improve the performance of such technology even further. This paper introduces QGateD-Polar, a novel Quantum Gate-based Maximum-Likelihood Decoder design for Polar error correction codes, which are becoming widespread in today's 5G and tomorrow's NextG wireless networks. QGateD-Polar uses quantum gates to dictate the time evolution of Polar code decoding -- from the received wireless soft data to the final decoded solution -- by leveraging quantum phenomena such as superposition, entanglement, and interference, making it amenable to quantum gate-based computers. Our early results show that QGateD-Polar achieves the Maximum Likelihood performance in ideal quantum simulations, demonstrating how performance varies with noise.

Published
2022

184. AirTrack: Onboard Deep Learning Framework for Long-Range Aircraft Detection and Tracking

Author

Ghosh, Sourish, Patrikar, Jay, Moon, Brady, Hamidi, Milad Moghassem, and Scherer, Sebastian

Subjects
Computer Science - Computer Vision and Pattern Recognition, Computer Science - Machine Learning, Computer Science - Robotics
Abstract

Detect-and-Avoid (DAA) capabilities are critical for safe operations of unmanned aircraft systems (UAS). This paper introduces, AirTrack, a real-time vision-only detect and tracking framework that respects the size, weight, and power (SWaP) constraints of sUAS systems. Given the low Signal-to-Noise ratios (SNR) of far away aircraft, we propose using full resolution images in a deep learning framework that aligns successive images to remove ego-motion. The aligned images are then used downstream in cascaded primary and secondary classifiers to improve detection and tracking performance on multiple metrics. We show that AirTrack outperforms state-of-the art baselines on the Amazon Airborne Object Tracking (AOT) Dataset. Multiple real world flight tests with a Cessna 182 interacting with general aviation traffic and additional near-collision flight tests with a Bell helicopter flying towards a UAS in a controlled setting showcase that the proposed approach satisfies the newly introduced ASTM F3442/F3442M standard for DAA. Empirical evaluations show that our system has a probability of track of more than 95% up to a range of 700m. Video available at https://youtu.be/H3lL_Wjxjpw ., Comment: 7 pages, 5 figures, ICRA 2023

Published
2022

193. Low-cost household water treatment : a techno-behavioural intervention for local sustainable development in Afghanistan

Author

Hamidi, Mohammad Daud

Abstract

Access to safe drinking water is a critical global challenge, in remote rural areas and urban centres alike. A pressing concern within this challenge lies in the sustainability of groundwater and the livelihoods reliant on it. However, a comprehensive study of such a complex issue as water insecurity requires a multidisciplinary approach that can synthesize perspectives from the natural and social sciences. With the overarching aim of studying and developing means to rectify water insecurity in low-income settings, this thesis pursues such an approach and contributes insights to the broader global dialogue through the case of the conflict-affected urban context of Kabul - where groundwater and livelihood challenges are driven especially by the contamination and rapid depletion of the local aquifers. The multidisciplinary study begins with a geo-hydrology perspective that explores the sources of groundwater and the factors contributing to groundwater contamination. Additionally, it explores the potential of using clay disc filters for household water treatment from an earth sciences perspective. Complementing these natural science perspectives, the research also incorporates the COM-B framework, which draws from psychology and behavioural science. By leveraging anthropological techniques with a firm grounding in development research, the thesis further adopts a bottom-up approach to inform survey research. Translating this multidisciplinary approach into the empirical research underlying this thesis, firstly, the groundwater recharge sources and groundwater dynamics in aquifers of Kabul city were explored relying on the analysis of the stable isotopic composition (δ18O and δ2H) of groundwater and surface water from the Upper Kabul River and Logar River. The results showed that precipitation was the primary source of recharge in the Central Kabul sub-basin, while mixed recharge from the river, precipitation, and irrigation return flow governed recharge in the Logar sub-basin. In the Paghman and Lower Kabul, and Upper Kabul sub-basins, increased rainfall input was also observed. The contribution of river water to groundwater recharge decreased from an average of over 60% in 2007 to less than 50% in 2020. Also, substantial groundwater level depletion was documented in the Central Kabul sub-basin and western parts of the city. In addition to examining recharge sources and rates, the bacteriological and chemical characteristics of Kabul's groundwater were analyzed. In Kabul, 4.1 million people rely on groundwater, making it critical to understand its contamination trends in the face of rapid development and social changes. The results showed an increase in E. coli and NO3-, indicating anthropogenic impacts on shallow groundwater quality. The Water Quality Index revealed that less than 35% of shallow groundwater samples had good quality. To address these issues, the implementation of point-of-use water purification was proposed as a temporary solution for reducing the occurrence of waterborne diseases. Moreover, a qualitative study, based on 68 semi-structured interviews, explored the factors limiting access to clean drinking water in two peri-urban areas in Kabul. These factors included dysfunctional water supply networks, water price inequalities, uneven development, and aid prioritization. In addition, the stressors and dynamic access to water such as droughts, contamination, and electricity disruption were documented. Further, this research examined the nature and underlying factors of inter-household water-sharing practices. Water availability, the costs to the donor, the frequency of requests for water, the period over which they operate, and religious beliefs were all found to play key roles in determining water-sharing practices. The added influence of droughts in limiting water-sharing practices further highlighted the dynamics in performing the behaviour. Furthermore, this research explored the factors that influence household water treatment practices, relied on a comprehensive behaviour change model (i.e., COM-B model). The results of the study showed that reflective and automatic motivation, as well as physical opportunity, had a statistically significant association with the performance of household water treatment behaviour. The findings suggest that socioeconomic, psychosocial, and contextual factors are all important in understanding and promoting household water treatment practices, and should be taken into account to develop interventions that are tailored to the specific needs and obstacles of different communities. Lastly, the potential of using clay disc filters, frequently termed ceramic water filters, made from locally-sourced clay samples, was explored for removing bacteria from water. The clay discs were produced by mixing clay and sorted sawdust in a ratio of 1:2, and the filtration rate was 1 litre per hour. Clay disc filters have the potential to be a low-cost and locally-sourced solution for improving water quality in Afghanistan, but further research and development is needed to optimize their production, particularly by leveraging the skills of local potters in Kabul. Overall, the synergistic combination of disciplinary techniques was thus capable of shedding light on the complex interplay between water resources, technology, and human behaviour (i.e., household water treatment) and provided a comprehensive understanding of the challenges and solutions surrounding access to safe drinking water.

Published
2023

195. 3D Near-Field Virtual MIMO-SAR Imaging Using FMCW Radar Systems at 77 GHz

Author

Hamidi, Shahrokh

Subjects
Electrical Engineering and Systems Science - Signal Processing
Abstract

In this paper, we present 3D high resolution radar imaging at millimeter-Wave (mmWave) frequencies by means of a combination of virtual Multiple Input Multiple Output (MIMO) Frequency Modulated Continuous Wave (FMCW) Radars and Synthetic Aperture Radar (SAR) which results in a compact, low-cost, and high-speed 3D mmWave imagery system with low complexity.

Published
2022

196. Residual Supersingular Iwasawa Theory over quadratic imaginary fields

Author

Hamidi, Parham

Subjects
Mathematics - Number Theory
Abstract

Let p be an odd prime and let E be an elliptic curve defined over a quadratic imaginary field where p splits completely. Suppose E has supersingular reduction at primes above p. We define and study the fine double-signed residual Selmer groups in these settings for Z_p^2-extensions. We prove that for two residually isomorphic elliptic curves, the vanishing of the signed {\mu}-invariants of one elliptic curve implies the vanishing of the signed {\mu}-invariants of the other. Finally, we show that the Pontryagin dual of the Selmer group and the double-signed Selmer groups have no non-trivial pseudo-null submodules for these extensions.

Published
2022

197. Uncaria nervosa Elmer, a new herbal source for betulinic acid and ursolic acid: Metabolites profiling, isolation, and in vitro cytotoxicity studies against T47D breast cancer [version 1; peer review: awaiting peer review]

Author

Noveri Rahmawati, Nor Hadiani Ismail, Fatma Sri Wahyuni, and Dachriyanus Hamidi

Subjects
Research Article, Articles, Isolation, cytotoxicity, LCMS/MS, T47D, Uncaria nervosa Elmer, MZMine, SIRIUS
Abstract

* Background Uncaria nervosa Elmer is an Indonesian herbal plant that is traditionally used for breast cancer. The results of phytochemical screening contained alkaloids, flavonoids, and terpenoids in the ethanol extract of this plant. Based on literature searches, reports regarding the bioactive compounds responsible for breast cancer have not been found. Further research is needed to understand the potential of Uncaria nervosa Elmer as a breast cancer treatment and to identify the specific compounds responsible for its effects Methods This study aims to determine the metabolite profiling of ethanol extract, the isolation, characterization of bioactive compounds, and their bioactivity in T47D breast cancer cells. The research began by extracting the leaves by maceration using 70% ethanol, and then solid phase extraction was carried out using the solid phase extraction (SPE) method. In this study, the sorbent used was polyamide. The extract was analyzed using a tandem analysis technique based on LCMS using the MZmine and SIRIUS platforms. Isolation was carried out using column chromatography, and preparative recycling HPLC. Bioactive compounds were characterized using UV, HPLC, NMR, and 2D NMR, as well as bioactivity tests using the MTT method. Results The results show that the extract contained N-[(1,3-dimethyl-2,6-dioxo-7-prop-2-ynylpurin-8-yl) amino] formamide, N-(3-phenylbutyl)hexan-2-amine, 1,1-Dichloro-1-nitrosopropane, ceratodictyol, betulinic acid, ursolic acid, 7-methyl-N-[6-[(7-methyl-6-oxooctanoyl) amino] hexyl]-6-oxononanamide, Nervisterol and 3,5,10-tris (acetyloxy)-2-hydroxy-4,14,16,16-tetramethyl-8-methylidene-13-oxo-15oxatetracyclo [9.4.1.0 1, 14.0 4, 9] hexadecan-7-yl 3-phenylprop-2-enoate. The ethanol extract of Uncaria nervosa Elmer leaves contains nine compounds consisting of alkaloids, terpenoids, and fatty acid. The bioactive compounds that were successfully isolated were betulinic acid, and ursolic acid, with IC 50 values of ˃100 and 14,70±4,50 μg/ml, respectively. These compounds were reported in this plant for the first time. Conclusion Betulinic acid, and ursolic acid have been successfully isolated from leaves Uncaria nervosa Elmer, and ursolic acid have moderate cytotoxic activity on T47D breast cancer cells.

Published
2024
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198. The impact of carbohydrate restriction-induced elevations in low-density lipoprotein cholesterol on progression of coronary atherosclerosis: the ketogenic diet trial study design

Author

Javier, Denise Alison R., Manubolu, Venkat S., Norwitz, Nicholas G., Kinninger, April, Aldana-Bitar, Jairo, Ghanem, Ahmed, Ahmad, Khadije, Vicuna, Will D., Hamidi, Hossein, Bagheri, Marziyeh, Elsayed, Tasneem, Villanueva, Bea, Ichikawa, Keishi, Flores, Ferdinand, Hamal, Sajad, Feldman, David, and Budoff, Matthew J.

Published
2024
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199. Compositionality under time pressure

Author

Rubino, Valerio, Hamidi, Mani, Dayan, Peter, and Wu, Charley M

Subjects
Cognitive Neuroscience, Decision making, Statistical learning, Computational Modeling, Symbolic computational modeling
Abstract

Compositionality is a central component of the human faculty for generalization and flexibility. However, the computations involved are poorly understood, especially in terms of their cognitive costs. On one hand, compositionality requires searching combinatorially large hypothesis spaces, raising issues of tractability.On the other hand, compositional representations afford efficient and compact compression. To shed light on the cognitive resource required for compositionality, we used a within-subject time pressure manipulation to study how participants navigated a series of mazes, generated using recursive operations over spatial primitives. We find evidence that behavior is guided by the use of primitives and abstract operations over them, where the degree of compositional structure increases performance and speeds up decisions.And while time pressure led to more random errors, it did not impair the capacity for compositionality. Rather, participants increased their reliance on reusing and recombining previous computations, suggesting a remarkable robustness of human compositional reasoning.

Published
2023

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