bluuebunny/crossref_metadata_2025 huggingface dataset:
Review of Computational Mechanics, Optimization, and Machine Learning Tools for Digital Twins Applied to Infrastructures
Authors: Stavroulakis Georgios E. , Charalambidi Barbara G. , Koutsianitis Panagiotis
Published: November 2022

This review discusses the links between the newly introduced concepts of digital twins and more classical finite element modeling, reduced order models, parametric modeling, inverse analysis, machine learning, and parameter identification. The purpose of this article is to demonstrate that development, as almost always is the case, is based on previously developed tools that are currently exploited since the technological tools for their implementation are available and the needs of their usage appear. This fact has rarely been declared clearly in the available literature. The need for digital twins in infrastructures arises due to the extreme loadings applied on energy-related infrastructure and to the higher importance that fatigue effects have. Digital twins promise to provide reliable and affordable models that accompany the structure throughout its whole lifetime, make fatigue and degradation prediction more reliable, and support effective predictive maintenance schemes.
Infill Variability and Modelling Uncertainty Implications on the Seismic Loss Assessment of an Existing RC Italian School Building
Authors: Mucedero Gianrocco , Perrone Daniele , Monteiro Ricardo
Published: November 2022

Past earthquake evidence has shown the high vulnerability of Italian school buildings, given by the extensive damage observed to structural and non-structural elements. Such vulnerability demonstrates the need to undertake a seismic risk assessment and reduction strategies for critical facilities and allocation of national funds for retrofit interventions to those regions where seismic risk is higher. To do so, Expected Annual Losses (EAL) are evermore considered one of the main seismic risk metrics, which can, however, be largely affected by the epistemic uncertainty that typically characterizes the material and geometrical properties of existing buildings, particularly masonry-infilled reinforced concrete (RC) ones. This paper investigates the implications of accounting for a thorough identification of sources and characterization of uncertainty in seismic loss estimates on the risk assessment of a typical Italian masonry-infilled RC school building. The variability in masonry infill properties and modeling assumptions, as well as the subsequent epistemic uncertainty, are explicitly considered in the loss estimation of the RC school building. Specifically, the impact on the expected annual loss ratio is quantified in terms of both structural and non-structural components, depending on the engineering demand parameter to which they are sensitive. The results show that, when considering the uncertainty related to the variability in masonry infills, higher loss ratios of up to 30% are obtained with respect to the available literature estimates.
Achievable Rate of NOMA-Based Cooperative Spectrum-Sharing CRN over Nakagami-m Channels
Authors: Alvi Sajid Hussain , Ali Bakhtiar , Mirza Jawad , Khaqan Ali , Javed Muhammad Awais , Ali Jehad , Hussain Niamat
Published: November 2022

Efficient data dissemination is a key challenge for IoT applications. In this paper, we present an ergodic achievable rate analysis of the non-orthogonal multiple access (NOMA)-based cooperative transmission scheme in spectrum-sharing cognitive radio networks (CRNs). The transmission scheme consists of two phases, where the NOMA transmission strategy is employed at the secondary transmitter (ST) in the second phase to serve the primary receiver (PR) and secondary receivers (SRs). This cooperative spectrum-sharing transmission is favourable when the ST-PR link is strong and the ST faces a spectrum scarcity issue. To evaluate the performance of the network over Nakagami-m channels, ergodic achievable rates at PR and SRs are derived in closed forms, which can be used for any integer or non-integer value of fading index m. Finally, we compare the results of the analytical expressions with simulated results for validation.
Applications of In Situ Neutron-Based Techniques in Solid-State Lithium Batteries
Authors: Abitonze Maurice , Yu Xiaohan , Diko Catherine Sekyerebea , Zhu Yimin , Yang Yan
Published: November 2022

Solid-state lithium batteries (SSLBs) have made significant progress in recent decades in response to increasing demands for improved safety and higher energy density. Nonetheless, the current state SSLBs are not suitable for wide commercial applications. The low ionic conductivity, lithium dendrites growth, and unstable interfaces between solid electrodes and electrolytes are some of the challenges that need to be overcome. Therefore, it is critical to fully comprehend the structural information of SSLBs at a nanometer scale. Neutron-based techniques (NBTs) are sensitive to light elements (H, Li, B, N, O, etc.) and can distinguish heavy metals (e.g., Mn, Fe, Co, Ni, etc.) containing close atomic numbers or even isotopes (e.g., 1H and 2H). Therefore, NBTs are important and powerful structural and analytical tools for SSLB research and have substantially improved our understanding of these processes. To provide real-time monitoring, researchers have explored many sophisticated in situ NBTs to investigate the underlying mechanisms of SSLBs. This minireview article is primarily dedicated to the investigation of SSLBs using in situ NBTs. In addition, it illustrates the capabilities of different in situ NBTs on SSLBs by illustrating the capabilities of different techniques in recently published works. Ultimately, some perspectives for the next evolution of in situ NBTs in SSLBs are highlighted.
The Effect of Concave-Side Intertransverse Ligament Laxity on the Stress of AIS Lumbar Spine Based on Finite Element Method
Authors: Zhang Linjie , Zhang Qiaolin , Zhang Yan , Arthur Musinguzi , Teo Ee-Chon , Bíró István , Gu Yaodong
Published: November 2022

(1) Background: Scoliosis has the mechanical characteristic of asymmetric stress distribution, which is one of the reasons for the aggravation of scoliosis. Bracing therapy is the best treatment for AIS, but it is difficult and costly to operate. Is it possible to reduce pressure in the concave side by relaxing the ITL in the concave side of scoliosis, so as to improve the abnormal stress distribution of scoliosis? In this paper, a finite element method was used to simulate the effect of the relaxation of concave-side ITL on the stress of a lumbar spine with scoliosis, which provides some guidance for the treatment of scoliosis. (2) Methods: Using CT images of a patient with scoliosis whose Cobb Angle was 43° and Lordosis Angle was 45, a scoliosis lumbar was established, and Young’s modulus of the ITL of the concave-side lumbar spine was reduced by 95% to simulate ligament relaxation. By comparing the stress condition of the model vertebral body with no ligament relaxation, the effect of concave-side ITL relaxation on the mechanical characteristics of scoliosis lumbar spine was explored. (3) Results: An effective and complete model of the lumbar spine was established. The concave ITL relaxed, which only had a great impact on the bending loads. After the ligament was relaxed, the stability of the spine was reduced. Stress concentration on the concave side of vertebrae and the IVD was aggravated. Under loads on the convex side, the maximum stress on the vertebral body and the IVD increased significantly, making lumbar vertebrae more vulnerable to injury. (4) Conclusions: Laxity of the ITL on the concave side of the AIS lumbar only affects the bending load. Laxity of the concave-side ligament will reduce the stability of the lumbar, aggravate the uneven stress distribution of scoliotic lumbar vertebrae, increase the risk of IVD injury, and be unfavorable for the scoliotic lumbar spine. Relaxation of the concave ITL alone is not an effective way to treat scoliosis.
Serum Iron Level and 10-Year Survival after Melanoma
Authors: Rowińska Karolina , Baszuk Piotr , Rogoża-Janiszewska Emilia , Deptuła Jakub , Marciniak Wojciech , Derkacz Róża , Lener Marcin , Cybulski Cezary , Kiedrowicz Magdalena , Boer Magdalena , Marchlewicz Mariola , Dębniak Tadeusz , Lubiński Jan
Published: November 2022

The malignant melanoma of the skin is a very aggressive tumor. The determination of prognostic biomarkers is important for the early detection of recurrence, and for the enrollment of the patients into different treatment regimens. An evaluation of a cohort of 375 Polish MM cases revealed that a low serum iron concentration (i.e., below 893.05 µg/L) was associated with increased mortality. The study group was followed up from the date of melanoma diagnosis until death or 2020. Patients were assigned to one of four categories in accordance with increasing iron level (I–IV quarters). Patients with a low iron level of below 893.05 µg/L (I quarter) had a significantly lower survival rate when compared to the subgroup with the highest iron level, above 1348.63 µg/L (IV quarter; HR = 4.12; p = 0.028 and HR = 4.66; p = 0.019 for uni- and multivariable models, respectively). Multivariable analysis took into account the following factors: iron levels, Clark, sex, and age. Future studies based upon the examination of a larger number of cases should be conducted to confirm our findings.
Protective Effect of Fustin against Huntington’s Disease in 3-Nitropropionic Treated Rats via Downregulation of Oxidative Stress and Alteration in Neurotransmitters and Brain-Derived Neurotrophic Factor Activity
Authors: Bin-Jumah May Nasser , Gilani Sadaf Jamal , Alabbasi Abdulaziz F. , Al-Abbasi Fahad A. , AlGhamdi Shareefa A. , Alshehri Ohoud Y. , Alghamdi Amira M. , Sayyed Nadeem , Kazmi Imran
Published: November 2022

Researchers have revealed that Rhus verniciflua heartwood, which contains fustin as an important component, possesses antioxidant-mediated, anti-mutagenic, and anti-rheumatoid arthritis characteristics. Additionally, out of the numerous plant-derived secondary metabolites, there are various research papers concentrating on flavonoids for potential advantages in neurological illnesses. The current study aims to assess the neuroprotective potential of fustin in rodents over 3-nitropropionic acid (3-NPA)-induced Huntington’s disease (HD)-like consequences. The efficacy of fustin 50 and 100 mg/kg was studied with multiple-dose administrations of 3-NPA, which experimentally induced HD-like symptoms in rats for 22 days. At the end of the study, several behavioral tests were performed including a beam walk, rotarod, and grip strength tests. Similarly, some biochemical parameters were assessed to support oxidative stress (reduced glutathione—GSH, superoxide dismutase—SOD, catalase—CAT, and malondialdehyde—MDA), alteration in neurotransmitters (gamma-aminobutyric acid—GABA—and glutamate), alteration in brain-derived neurotrophic factor activity, and nitrite levels. Additionally, pro-inflammatory parameters were carried out to evaluate the neuroinflammatory responses associated with streptozotocin such as TNF-α, IL-1β, and COX in the perfused brain. The fustin-treated group exhibited a significant restoration of memory function via modulation in behavioral activities. Moreover, 3-NPA altered biochemical, neurotransmitters, brain protein levels, and neuroinflammatory measures, which fustin efficiently restored. This is the first report demonstrating the efficacy of novel phytoconstituent fustin as a potential future candidate for the treatment of HD via offering neuroprotection by subsiding the oxidative and enzymatic activity in the 3-NPA experimental animal paradigm.
A Genome-Wide Association Study into the Aetiology of Congenital Solitary Functioning Kidney
Authors: Groen in ’t Woud Sander , Maj Carlo , Renkema Kirsten Y. , Westland Rik , Galesloot Tessel , van Rooij Iris A. L. M. , Vermeulen Sita H. , Feitz Wout F. J. , Roeleveld Nel , Schreuder Michiel F. , van der Zanden Loes F. M.
Published: November 2022

Congenital solitary functioning kidney (CSFK) is a birth defect that occurs in 1:1500 children and predisposes them to kidney injury. Its aetiology is likely multifactorial. In addition to known monogenic causes and environmental risk factors, common genetic variation may contribute to susceptibility to CSFK. We performed a genome-wide association study among 452 patients with CSFK and two control groups of 669 healthy children and 5363 unaffected adults. Variants in two loci reached the genome-wide significance threshold of 5 × 10−8, and variants in 30 loci reached the suggestive significance threshold of 1 × 10−5. Of these, an identified locus with lead single nucleotide variant (SNV) rs140804918 (odds ratio 3.1, p-value = 1.4 × 10−8) on chromosome 7 was most promising due to its close proximity to HGF, a gene known to be involved in kidney development. Based on their known molecular functions, both KCTD20 and STK38 could explain the suggestive significant association with lead SNV rs148413365 on chromosome 6. Our findings need replication in an independent cohort of CSFK patients before they can be established definitively. However, our analysis suggests that common variants play a role in CSFK aetiology. Future research could enhance our understanding of the molecular mechanisms involved.
Coupling CRISPR/Cas9 and Lambda Red Recombineering System for Genome Editing of Salmonella Gallinarum and the Effect of ssaU Knock-Out Mutant on the Virulence of Bacteria
Authors: Tahir Hamza , Basit Abdul , Tariq Hafsa , Haider Zulquernain , Ullah Asim , Hayat Zafar , Rehman Shafiq Ur
Published: November 2022

The poultry industry in developing countries still faces a significant threat from fowl typhoid, a disease caused by Salmonella Gallinarum that has been well contained in more economically developed countries. In addition to the virulence exhibited by large virulence plasmid (85 kb), Salmonella Pathogenicity Island 2 in S. Gallinarum plays a key role in mediating disease through its type III secretion systems (TTSS). The TTSS secrete effector protein across the Salmonella containing vacuoles and mediate the internalization of bacteria by modulating vesicular passage. In this study, candidate virulent ssaU gene (~1 kb) encoding type III secretion system was successfully deleted from indigenously isolated S. Gallinarum genome through homology-directed repair using CRISPR/Cas9 and lambda recombination systems. CRISPR/Cas9-based genome editing of poultry-derived Salmonella Gallinarum has not been previously reported, which might be linked to a lack of efficiency in its genetic tools. This is the first study which demonstrates a complete CRISPR/Cas9-based gene deletion from this bacterial genome. More importantly, a poultry experimental model was employed to assess the virulence potential of this mutant strain (ΔssaU_SG18) which was unable to produce any mortality in the experimentally challenged birds as compared to the wild type strain. No effect on weight gain was observed whereas bacteria were unable to colonize the intestine and liver in our challenge model. This in vivo loss of virulence in mutant strain provides an excellent functionality of this system to be useful in live vaccine development against this resistant and patho genic bacteria.
Silicon Carbide Precursor: Structure Analysis and Thermal Behavior from Polymer Cross-Linking to Pyrolyzed Ceramics
Authors: Vry Sébastien , Roumanie Marilyne , Bayle Pierre-Alain , Rolère Sébastien , Bernard-Granger Guillaume
Published: November 2022

The Silres H62C methyl-phenyl-vinyl-hydrogen polysiloxane is a promising candidate as a SiC precursor for 3D printing based on photopolymerization reaction. An in-depth nuclear magnetic resonance spectroscopy analysis allowed us to determine its structure and quantify its functional groups. The polysiloxane was found to have a highly branched ladder-like structure, with 21.9, 31.4 and 46.7% of mono-, di- and tri-functional silicon atoms. The polysiloxane cross-links from 180 °C using hydrosilylation between silyl groups (8.4% of the total functional groups) and vinyl groups (12.0%) and contains a non-negligible ethoxy content (2.4%), allowing cross-linking through a hydrolyze/condensation mechanism. After converting the polymer into ceramic and thus releasing mainly hydrogen and methane, the ceramic yield was 72.5%. An X-ray diffraction analysis on the cross-linked and pyrolyzed polysiloxane showed that the ceramic is amorphous at temperatures up to 1200 °C and starts to crystallize from 1200 °C, leading into 3C-SiC carbon-rich ceramic at 1700 °C in an argon atmosphere.
Deep Complex-Valued Convolutional Neural Network for Drone Recognition Based on RF Fingerprinting
Authors: Yang Jie , Gu Hao , Hu Chenhan , Zhang Xixi , Gui Guan , Gacanin Haris
Published: November 2022

Drone-aided ubiquitous applications play important roles in our daily lives. Accurate recognition of drones is required in aviation management due to their potential risks and disasters. Radiofrequency (RF) fingerprinting-based recognition technology based on deep learning (DL) is considered an effective approach to extracting hidden abstract features from the RF data of drones. Existing deep learning-based methods are either high computational burdens or have low accuracy. In this paper, we propose a deep complex-valued convolutional neural network (DC-CNN) method based on RF fingerprinting for recognizing different drones. Compared with existing recognition methods, the DC-CNN method has a high recognition accuracy, fast running time, and small network complexity. Nine algorithm models and two datasets are used to represent the superior performance of our system. Experimental results show that our proposed DC-CNN can achieve recognition accuracies of 99.5% and 74.1%, respectively, on four and eight classes of RF drone datasets.
Automated Sortie Scheduling Optimization for Fixed-Wing Unmanned Carrier Aircraft and Unmanned Carrier Helicopter Mixed Fleet Based on Offshore Platform
Authors: Liu Zixuan , Han Wei , Wu Yu , Su Xichao , Guo Fang
Published: November 2022

Optimizing naval aircraft deck sortie scheduling is important for improving the sortie efficiency of naval aircraft groups. It is also an important link in realizing the automated scheduling of aircraft carriers. Firstly, a single-aircraft surface transit path library was constructed. This paper used the improved A* algorithm and the optimal control deck path planning algorithm to construct the transit path library between the deck parking position and take-off position, or between warmable and non-warmable parking positions. Secondly, a mathematical optimization model was constructed for the sortie scheduling of a mixed fleet of fixed-wing carrier aircraft and carrier helicopters. The model took the maximum sortie time of the fleet and taxiing time of the fleet of fixed-wing aircraft as the optimization objectives, and considered the process flow, spatial, and resource constraints. Thirdly, a discretized improved whale optimization algorithm (IWOA) was designed to solve the problem. To improve the optimization-seeking capability of the algorithm, we discretized the algorithm, optimized its coding method, and introduced pre-constraints, learning factors, parameter improvements, and population restart. Finally, we set up various cases and proposed a new strategy for simulation experiments: these simulations verified the validity of the model, the excellent optimization performance of the IWOA, and the superiority of the sortie strategy. The research in this study will help to implement automated aircraft carrier scheduling.
Private Key and Decoder Side Information for Secure and Private Source Coding
Authors: Günlü Onur , Schaefer Rafael F. , Boche Holger , Poor Harold Vincent
Published: November 2022

We extend the problem of secure source coding by considering a remote source whose noisy measurements are correlated random variables used for secure source reconstruction. The main additions to the problem are as follows: (1) all terminals noncausally observe a noisy measurement of the remote source; (2) a private key is available to all legitimate terminals; (3) the public communication link between the encoder and decoder is rate-limited; and (4) the secrecy leakage to the eavesdropper is measured with respect to the encoder input, whereas the privacy leakage is measured with respect to the remote source. Exact rate regions are characterized for a lossy source coding problem with a private key, remote source, and decoder side information under security, privacy, communication, and distortion constraints. By replacing the distortion constraint with a reliability constraint, we obtain the exact rate region for the lossless case as well. Furthermore, the lossy rate region for scalar discrete-time Gaussian sources and measurement channels is established. An achievable lossy rate region that can be numerically computed is also provided for binary-input multiple additive discrete-time Gaussian noise measurement channels.
The Electromagnetic Vacuum Field as an Essential Hidden Ingredient of the Quantum-Mechanical Ontology
Authors: Cetto Ana Maria , de la Peña Luis
Published: November 2022

This paper provides elements in support of the random zero-point radiation field (zpf) as an essential ontological ingredient needed to explain distinctive properties of quantum-mechanical systems. We show that when an otherwise classical particle is connected to the zpf, a drastic, qualitative change in the dynamics takes place, leading eventually to the quantum dynamics. In particular, we demonstrate that in parallel with the evolution of the canonical variables of the particle into quantum operators satisfying the basic commutator x^,p^=iℏ, also the field canonical variables are transformed, giving rise to the corresponding creation and annihilation operators a^†,a^, satisfying a^,a^†=1. This allows for an explanation of quantum features such as quantum fluctuations, stationary states and transitions, and establishes a natural contact with (nonrelativistic) quantum electrodynamics.
Public Expenses in Education and Youth Unemployment Rates—A Vector Error Correction Model Approach
Authors: Mehmetaj Nevila , Xhindi Nevila
Published: November 2022

In the last decade, much of the attention of public expenditures in education has been focused on improving the offer to the labor market to minimize unemployment rates among young people. Since education directly affects human capital, investing in higher education is considered a benefit to future employment. Therefore, it is the purpose of this paper to investigate whether the government-allocated share of funds to total public expenditures in education affects the unemployment rates of youth in Albania. A quantitative analysis of total public expenses in education and of the country’s economic growth rates is used to investigate their effects on youth unemployment rates in the country. This is followed by another deeper investigation of public expenses in higher education and the country’s economic growth rates analysis on the youth unemployment rates of tertiary education graduates in Albania. Time series data are used in a set of econometric analyses such as the Augmented Dickey–Fuller test, Johansen test, and vector error correction (VEC) model to test for short-run dynamics and long-run causalities among the variables. The study results reveal that there is a short-term causality between the real economic growth rate and the youth unemployment rate, while there is a long-term causality between total public expenditures in education and the youth unemployment rate. If total public expenditures in education increase by 1%, the youth unemployment rate would decrease by 10.81%. Similarly, but not so strong, there is a long-term causality between public expenditures in higher education and the graduated youth unemployment rate. If public expenditures in higher education increase by 1%, the graduated youth unemployment rate would decrease by 5.85%. The speed of adjustment from the short-run to long-run equilibrium, in a quarter time, of the youth unemployment rate is 22%, while of the graduated youth unemployment rate is 53%—showing a faster convergence.
Content Aspects of Professional Training of a Specialist in the Development of Individual Educational Trajectories
Authors: Andreeva Antonina , Kalmykova Svetlana , Shoshmina Irina
Published: November 2022

This article lists the prerequisites for the emergence of new interdisciplinary professions at the intersection of pedagogy, information and communication technologies. A new promising profession of a developer of individual educational trajectories is given, described in the “Atlas of New Professions 3.0”, developed under the auspices of the Agency for Strategic Initiatives. As conceived by the authors, this is a professional who creates a route for training new specialists from courses offered by educational institutions, including those available online, as well as simulators, simulators, internships, etc., and develops an educational track based on them, considering the psychotype, abilities and goals individual person. Since a brief description of this profession in the Atlas does not give a complete picture of its content, for the purposes of understanding the meaningful aspect of the professional training of such specialists in a multidisciplinary university, a description of the methodological basis of the developer of individual educational trajectories is given. The authors of this article describe the principle of operation of the constructor, developed at SPbPU and allowing the selection of the content of professional training of the developer of individual educational trajectories in a multidisciplinary university.
Nutritional Status of Slovene Adults in the Post-COVID-19 Epidemic Period
Authors: Jakše Boštjan , Godnov Uroš , Pinter Stanislav
Published: November 2022

Background: Monitoring nutritional status data in the adult population is extremely important to mediate their health status. Unfortunately, for Slovenia (2.1 million European Union citizens), data on the body composition status of the general adult population are currently rare or nonexistent in scientific journals. Furthermore, dietary intake was last assessed several years before the COVID-19 epidemic period. Methods: We randomly recruited 844 adult Slovenes from all regions of Slovenia. The primary aim of the cross-sectional study was to examine body composition status (using a medically approved electrical bioimpedance monitor) during the post-COVID-19 epidemic period. In addition, we assessed dietary intake (using a standardized food frequency questionnaire) and compared the obesity propensity for both sexes separately using the body mass index (BMI) and body fat percentage (FAT%) obesity classification of the World Health Organization. Results: Regarding BMI classification, 43% of the whole sample was overweight (28%) or obese (15%), and there were more older adults than adults (64% vs. 42%, p < 0.001). The average FAT% of adult females and males was 26.9% and 19.5% (p < 0.001), respectively, while for older adult females and males, it was 32.7% and 23% (p < 0.001). In addition, a comparison of the proportions of obese people between the two cut-off obesity classifications (BMI vs. FAT%) showed a significantly underestimated proportion of obese female participants based on BMI classification (13% vs. 17%, p = 0.005). In terms of the dietary intake of the assessed nutrients in comparison with the national dietary reference values for energy and nutrient intake, the participants, on average, had lower intake than the recommended values for carbohydrates, fiber, vitamins C, D and E (for males) and calcium, and higher intake than the recommended values for total fat, saturated fatty acids, cholesterol, sodium and chloride (for males). Conclusions: The results urgently call for the need to not only improve the overall national nutritional status but also for regular national monitoring of body composition and dietary intake statuses.
An Inline V-Band WR-15 Transition Using Antipodal Dipole Antenna as RF Energy Launcher @ 60 GHz for Satellite Applications
Authors: Varshney Atul , Sharma Vipul , Elfergani Issa , Zebiri Chemseddine , Vujicic Zoran , Rodriguez Jonathan
Published: November 2022

This article demonstrates the design and development of WR-15 transition using an antipodal microstrip dipole antenna at a frequency of 60 GHz for space applications. An inline microstrip line to rectangular waveguide (MS-to-RWG) transition is proposed for the V-band (50–75 GHz) functioning. The RF energy is coupled and launched through an antipodal dipole microstrip antenna. Impedance matching and mode matching between the MS line and dipole are achieved by a quarter wave impedance transformer. This results in the better performance of transitions in terms of insertion loss (IL > −0.50 dB) and return loss (RL < −10 dB) for a 40.76% relative bandwidth from 55.57 GHz to 65.76 GHz. The lowest values of IL and RL at 60 GHz are −0.09 dB and −32.05 dB, respectively. A 50 μm thick double-sided etched InP substrate material is used for microstrip antipodal dipole antenna design. A back-to-back designed transition has IL > −0.70 dB and RL < −10 dB from 54.29 GHz to 64.07 GHz. The inline transition design is simple in structure, easy to fabricate, robust, compact, and economic; occupies less space because the transition size is exactly equal to the WR-15 length; and is prepared using an InP substrate with high permittivity of 12.4 and thickness of 50 μm. Thus, the devices have the lowest insertion loss value and lowest return loss (RL) value, of <−31 dB, as compared to earlier designs in the literature. Therefore, the proposed design has the lowest radiation loss (because of thickness) and highest transmission (about 97% power). Easy impedance matching using only a single-step quarter-wave transformer between the antipodal dipole antenna and 50 Ω microstrip line (avoiding the multi-sections’ demand and microstrip line’s tedious complexity) is needed. Since, when the InP dielectric substrate is inserted in WR-15, the waveguide becomes a dielectric-filled waveguide (DFWG), and its characteristics impedance reduces to 143 Ω from 505 Ω at an operating frequency of 60 GHz. In the proposed transition, no ridge waveguide or waveguide back-short is utilized in WR-15. The microstrip line did not contain any via, fence, window, screw, galvanic structure, post, etc. Hence, the transition is suitable for high-data-rate 5G communications, satellite remote sensing, missile navigation, MIC/MMIC circuits’ characterization, and mm-wave applications. The electrical equivalent model of the proposed design has been generated and validated using an RF circuit simulator and was found to have excellent matching.
An Overview of Medium Access Control and Radio Duty Cycling Protocols for Internet of Things
Authors: Amin Farhan , Abbasi Rashid , Khan Salabat , Abid Muhammad Ali
Published: November 2022

The Internet of Things (IoT) applications such as smart grids, smart agriculture, smart cities, and e-healthcare are popular nowadays. Generally, IoT end devices are extremely sensitive to the utilization of energy. The medium access control (MAC) layer is responsible for coordination and access of the IoT devices. It is essential to design an efficient MAC protocol for achieving high throughput in IoT. Duty cycling is a fundamental process in wireless networks and also an energy-saving necessity if nodes are required to operate for more than a few days. Numerous MAC protocols along with different objectives have been proposed for the IoT. However, to the best of our knowledge, only limited work has been performed dedicated to covering MAC and radio duty cycling (RDC). Therefore, in this study, we propose a systematic cataloging system and use if to organize the most important MAC and RDC proposals. In this catalog, each protocol has been categorized into main ideas, advantages, applications, limitations, innovative features, and potential future improvements. Our critical analysis is different from previous research studies, as we have fully covered all recent studies in this domain. We discuss challenges and future research directions.
Analysis of DC-Side Snubbers for SiC Devices Application
Authors: Liang Mei , Chen Jiwen , Jia Pengyu
Published: November 2022

Due to parasitic parameters existing in Silicon Carbide (SiC) devices application, SiC devices have poor turn-off performances. SiC diode and SiC MOSFET have severe turn-off overvoltage and oscillation. The DC-side snubber is one simple suppressing method. The simplest circuit is the high-frequency decoupling capacitor in parallel with the bridge leg. However, choosing the component value is empirical. Based on the turn-off terminal impedances of the SiC diode and the SiC MOSFET, the suppressing mechanism of this DC-side snubber is analyzed. The guideline selection for the component value is provided. Furthermore, the DC-side snubber with a damping resistor is analyzed based on the terminal impedances. The design principles are provided. Finally, the validity and effectiveness of the DC-side snubbers were proven based on the double-pulse test platform.
Multi-Modal Haptic Rendering Based on Genetic Algorithm
Authors: Li Yucheng , Wang Fei , Tao Liangze , Wu Juan
Published: November 2022

Multi-modal haptic rendering is an important research direction to improve realism in haptic rendering. It can produce various mechanical stimuli that render multiple perceptions, such as hardness and roughness. This paper proposes a multi-modal haptic rendering method based on a genetic algorithm (GA), which generates force and vibration stimuli of haptic actuators according to the user’s target hardness and roughness. The work utilizes a back propagation (BP) neural network to implement the perception model f that establishes the mapping (I=f(G)) from objective stimuli features G to perception intensities I. We use the perception model to design the fitness function of GA and set physically achievable constraints in fitness calculation. The perception model is transformed into the force/vibration control model by GA. Finally, we conducted realism evaluation experiments between real and virtual samples under single or multi-mode haptic rendering, where subjects scored 0-100. The average score was 70.86 for multi-modal haptic rendering compared with 57.81 for hardness rendering and 50.23 for roughness rendering, which proved that the multi-modal haptic rendering is more realistic than the single mode. Based on the work, our method can be applied to render objects in more perceptual dimensions, not only limited to hardness and roughness. It has significant implications for multi-modal haptic rendering.
A Study on the Design Procedure of Re-Configurable Convolutional Neural Network Engine for FPGA-Based Applications
Authors: Kumar Pervesh , Ali Imran , Kim Dong-Gyun , Byun Sung-June , Kim Dong-Gyu , Pu Young-Gun , Lee Kang-Yoon
Published: November 2022

Convolutional neural networks (CNNs) have become a primary approach in the field of artificial intelligence (AI), with wide range of applications. The two computational phases for every neural network are; the training phase and the testing phase. Usually, testing is performed on high-processing hardware engines, however, the training part is still a challenge for low-power devices. There are several neural accelerators; such as graphics processing units and field-programmable-gate-arrays (FPGAs). From the design perspective, an efficient hardware engine at the register-transfer level and efficient CNN modeling at the TensorFlow level are mandatory for any type of application. Hence, we propose a comprehensive, and step-by-step design procedure for a re-configurable CNN engine. We used TensorFlow and Keras libraries for modeling in Python, whereas the register-transfer-level part was performed using Verilog. The proposed idea was synthesized, placed, and routed for 180 nm complementary metal-oxide semiconductor technology using synopsis design compiler tools. The proposed design layout occupies an area of 3.16 × 3.16 mm2. A competitive accuracy of approximately 96% was achieved for the Modified National Institute of Standards and Technology (MNIST) and Canadian Institute for Advanced Research (CIFAR-10) datasets.
Effects of Water–Rock Interaction on the Permeability of the Near-Well Reservoir in an Enhanced Geothermal System
Authors: Feng Bo , Cui Zhenpeng , Liu Xiyao , Shangguan Shuantong , Qi Xiaofei , Li Shengtao
Published: November 2022

During the operation of an enhanced geothermal system (EGS), the non-equilibrium temperature, pressure, and hydrochemistry caused by fluid injection intensify water–rock interactions, induce the mineral dissolution and precipitation in the reservoir near an injection well (also referred to as the near-well reservoir), and change reservoir permeability, thus affecting continuous and efficient geothermal exploitation. Based on the investigation of the M-1 injection well of the EGS in the Matouying uplift of Hebei Province, China, a THC reactive solute transport model using the TOUGHREACT program was established in this study to explore the mineral dissolution and precipitation laws of the near-well reservoir and their influencing mechanisms on the reservoir porosity and permeability in the long-term fluid injection of this well. As indicated by the results, the dissolution of primary feldspar and chlorite and the precipitation of secondary minerals (mainly dolomite and illite) occurred and water–rock interaction significantly reduced the porosity and permeability of the near-well reservoir in the long-term continuous injection process. Appropriate reduction in the injection flow rate, injection temperature, and the Mg2+ and K+ contents in the injected water can help inhibit the formation of secondary minerals and delay the plugging process of the near-well reservoir.
Pyrolytic Depolymerization Mechanisms for Post-Consumer Plastic Wastes
Authors: Kohli Kirtika , Chandrasekaran Sriraam R. , Prajapati Ravindra , Kunwar Bidhya , Al-Salem Sultan , Moser Bryan R. , Sharma Brajendra K.
Published: November 2022

Fast pyrolysis of five post-consumer plastic waste materials was studied using pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS) technique. Prescription medicine bottles, landfill liners, and one type of industrial plastic waste represented polyolefin-based polymers, whereas packaging material represented polystyrene, and other industrial plastic waste represented polyurethane. The noncatalytic and catalytic degradation mechanisms of all five post-consumer plastic wastes were elucidated. The noncatalytic pyrolysis experiments were conducted at a temperature of 600 °C for a residence time of 5 min. For catalytic pyrolysis, a spent FCC catalyst was utilized for polystyrene, a sulfated zirconia-based catalyst was utilized for polyurethane, and a Y-zeolite catalyst was used for polyolefinic plastic waste. The results suggested that the thermal reaction has higher monomeric and oligomeric selectivity than the catalytic reaction. Results from the catalytic runs showed that the addition of catalysts greatly influences product compositions and has a significant effect on the selectivity of a specific compound. One of the plastic wastes, landfill liner, was selected for a batch scale pyrolysis at 420–440 °C using Y-zeolite as a catalyst to demonstrate the product properties and potential use of the liquid product formed. The complete product distribution of plastic crude oil was performed followed by distillation to produce aviation range fuel. The fuel properties of aviation range fuel were examined, and results suggested that the fuel fraction can be easily blended with commercially available fuels for direct applications.
The Electricity Generation Dispatch in Mexico: An Uncertain Road towards Sustainability
Authors: Miranda Karla , Tarín-Santiso Ana Victoria , Llamas-Terrés Armando , Probst Oliver
Published: November 2022

A comprehensive assessment was conducted for the electricity dispatch in the Mexican National Interconnected System for the 2017–2021 period, as well as the projected period of 2022–2030, with special attention on emissions and the transition to clean energy. The reported official generation data for the 2017–2021 period were compared to the results of both one- and multi-node dispatch modeling. The officially reported generation mix was found to be sub-optimal in terms of costs and emissions. A small part of the differences can be traced back to transmission constraints. Some of the remaining discrepancies can be explained by out-of-merit order dispatch favoring fossil fuel power plants. While transmission constraints were not critical for the 2017–2021 period, an increasing unbalance between regions with cost-effective generation (exporting regions) and importing regions was found, calling for inter-region transmission corridor reinforcements in the near future. The 2022–2030 emissions dramatically depend on the contemplated scenario. The existing project pipeline would allow for a 45% fraction of clean electricity by 2024, but the projection of current policies, with a renewed focus on generation from fossil fuels, makes a reduced generation from clean sources more likely. A clear policy path is required to bring Mexico’s emissions in line with its national and international clean energy and climate change mitigation goals.
Improved Moth Flame Optimization Approach for Parameter Estimation of Induction Motor
Authors: Danin Zekharya , Sharma Abhishek , Averbukh Moshe , Meher Arabinda
Published: November 2022

The effective deployment of electrical energy has received attention because of its environmental implications. On the other hand, induction motors are the primary equipment used in many industries. Industrial facilities demand the maximum percentage of energy. This energy demand is determined by the operating circumstances imposed by the internal characteristics of the induction motor. Because internal parameters of an induction motor are not immediately measurable, they must be obtained through an identification process. This paper proposed an improved version of moth flame optimization (IMFO) for the efficient parameter estimation of induction motors. A steady-state equivalent circuit of the induction motor is employed for the simulation. The proposed technique handles the parameter estimation problem better than moth flame optimization (MFO), particle swarm optimization (PSO), the flower pollination algorithm (FPA), the tunicate swarm algorithm (TSA), and the sine cosine algorithm (SCA). The anticipated IMFO reduces the cost function by 49.38% as compared with the basic version of MFO.
Numerical Study on Hydraulic Fracture Propagation in a Layered Continental Shale Reservoir
Authors: Han Lili , Li Yanyan , Hu Wei , Wei Siyu , Wang Wei , Zhang Fengyan , Wang Ye
Published: November 2022

The distribution of beddings varies greatly in shale reservoirs. The influence of beddings on hydraulic fracture propagation has often been studied using simplified geological models, i.e., uniformly distributed bedding models. However, the propagation processes of hydraulic fractures in shale reservoirs with complicated distributed beddings remains unclear. In this research, an outcrop-data-based bedding model of a continental shale formation in the Ordos Basin, China, is built. A mathematical model for fracture propagation is built using the discrete element method and is then verified by a hydraulic fracturing experiment. Reservoir-scale simulations are employed to investigate the influence of geological factors and engineering factors on fracture geometry. The study finds that beddings have significant inhibitory effects on fracture height growth; hydraulic fractures have difficulty in breaking through zones with densely distributed beddings. If a hydraulic fracture encounters a bedding plane with a larger aperture, it is more likely to be captured and expand along the weak interface. High vertical stress difference and a high fluid injection rate can promote the vertical penetration of hydraulic fractures through beddings and activate the bedding system to yield a complex fracture network. Increments in fluid viscosity can increase the resistance of fracture propagation, thereby reducing fracture complexity.
Flat Unglazed Transpired Solar Collector: Performance Probability Prediction Approach Using Monte Carlo Simulation Technique
Authors: Parimita Panigrahi Sajna , Kumar Maharana Sarat , Rajashekaraiah Thejaraju , Gopalashetty Ravichandran , Sharifpur Mohsen , Ahmadi Mohammad Hossein , Saleel C. Ahamed , Abbas Mohamed
Published: November 2022

Engineering applications including food processing, wastewater treatment, home heating, commercial heating, and institutional heating successfully use unglazed transpired solar collectors (UTCs). Trapping of solar energy is the prime goal of developing an unglazed transpired solar collector. The UTC is usually developed in and around the walls of the building and absorbs the solar energy to heat the air. One of the key challenges faced by the UTC designer is the prediction of performance and its warranty under uncertain operating conditions of flow variables. Some of the flow features are the velocity distribution, plate temperature, exit temperature and perforation location. The objective of the present study was to establish correlations among these flow features and demonstrate a method of predicting the performance of the UTC. Hence, a correlation matrix was generated from the dataset prepared after solving the airflow over a perforated flat UTC. Further, both strong and weak correlations of flow features were captured through Pearson’s correlation coefficient. A comparison between the outcomes from a linear regression model and that of computational simulation was showcased. The performance probability for the UTC was interlinked with correlation matrix data. The Monte Carlo simulation was used to predict the performance from random values of the flow parameters. The study showed that the difference between the free stream value of temperature and the value of temperature inside the UTC’s chamber varied between 15 and 20 °C. The probability of achieving system efficiency greater than 35% was 55.2%. This has raised the hope of recommending the UTC for drying and heating where the required temperature differential is within 20 °C.
Method of Qualitative–Environmental Choice of Devices Converting Green Energy
Authors: Olejarz Tadeusz , Siwiec Dominika , Pacana Andrzej
Published: November 2022

In the plan of the European Green Deal, the European Union assumed that by 2050 Europe will become the first climate-neutral continent in the world. This will be supported by alternative (renewable) energy sources (RESs), also termed green energy (GE). Their use should have long-term environmental benefits. To do this, it is necessary to skillfully select RES products. Therefore, the purpose is to develop a method for selecting devices that convert to GE, including not only qualitative criteria, but also environmental criteria and their price. The method is based on customer requirements and expert knowledge. The general concept of the method allows for the assessment of selected qualitative and environmental criteria of products and determining the price of purchase of these products. In a hybrid way, the following techniques were used: SMARTER method, brainstorming (BM), MAP method (alternative-punctual Czechowski’ method), ACJ method (price–qualitative analysis). Based on the results of qualitative criteria assessments or qualitative and environmental criteria assessments, the customer can select the best product. The customer can also select products, including the price of purchase, based on results from ACJ. A test of the method was carried out for solar collectors. The results testify to the possibility of controlling the selection control. The originality of this study is the creation of an uncomplicated sequence of techniques that provide the customer with the choice of RESs. The novelty of the method is the possibility of evaluating any products. In this study, the method is dedicated to devices converting GE, e.g., solar collectors.