bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of Structural and Optical Characteristics of Biopolymer Composites Based on Polyvinyl Alcohol Inserted with PbS Nanoparticles
Authors: Darwesh Ari H. A. , Mohammed Pshko A. , Mamand Soran M. , Hussen Sarkawt A. , Aziz Shujahadeen B. , Brza Mohamad A. , Abdullah Ranjdar M. , Karim Wrya O.
Published: March 2023

The film casting method is implemented to synthesize a series of films consisting of polyvinyl alcohol (PVA) films and 4 wt%, 8 wt%, and 12 wt% lead sulfide (PbS) nanoparticles (NPs). X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and Ultraviolet-visible (UV-vis) spectroscopy were used to ensure the impact of PbS loading on PVA properties, particularly optical ones. The FTIR results show a decrease in the intensity for all the bands and the XRD results show different features for the composites from that of the pure PVA. The optical properties, including optical transmission, surface reflection, and absorption, were investigated. Additionally, the significant optical parameters, for instance, the dielectric nature and refractive index of the films, were analyzed. The findings have shown that PbS NPs in the PVA films decrease UV and visible transmission through polymer composites and increase their ability to reflect the incident light. Tauc’s equation is applied to determine the optical bandgap energy (Eg) and verify whether it is direct or indirect. Using the relation between photon energy and optical dielectric loss, the Eg was measured and the type of electron transition was measured, which eases the exponent value (𝜸) specification from Tauc’s method. The Eg decreases from 6.3 eV to 5.25 eV when PbS NPs are added. The refractive index is improved from 1.27 to 2.16 for the polymer nanocomposite (NCPs) film with optimum PbS NPs. Then, the Wemple–DiDomenico model corresponding to a single oscillator is applied to the dispersive medium to determine the refractive index dispersion. Both the dispersive energy (Ed) and single-oscillator energy (Eo) are evaluated accurately. Moreover, the variation of both real and imaginary parts of the dielectric constant of polymer films were studied. Finally the optical parameters such as charge density, dielectric constant at high frequencies, optical mobility (µ), angular frequency (ωp), optical resistivity (ρ), and relaxation time (τ) of electrons are shown quantitatively. The ωp of the electron is increased from 1.06 × 1029 to 81.5 × 1029 Hz when the PbS NPs is added. The µ of the electrons is also increased from 4.85 to 6.22 cm2/(V·s) by adding the PbS NP.
Prickly Pear Fruit Extract: Capping Agent for the Sol–Gel Synthesis of Discrete Titanium Dioxide Nanoparticles and Sensitizer for Dye-Sensitized Solar Cell
Authors: Rajendhiran Radhika , Atchudan Raji , Palanisamy Jayabal , Balasankar Athinarayanan , Oh Tae Hwan , Deivasigamani Venugopal , Ramasundaram Subramaniyan
Published: March 2023

Plant extracts have been utilized as an ecofriendly natural reducing agent for the synthesis of nanomaterials, including metal oxides. Prickly pear (opuntia) fruit extract (PPE) was used as a reducing agent for the sol–gel synthesis of titanium dioxide nanoparticles (TiO2 NPs) and as a sensitizer for the TiO2 NPs photoanode used in dye-sensitized solar cells (DSSCs). Ultraviolet-visible and infrared spectra, X-ray diffraction patterns, and scanning electron microscopic images were confirmed in the formation of semiconducting TiO2 NPs with the predominate size of ~300 nm. The use of PPE rendered discrete TiO2 NPs, whereas the typical synthesis without PPE resulted TiO2 aggregates. TiO2 NPs had a tetragonal crystalline structure, and their grain size was varied with respect to the concentration of PPE. The size of TiO2 crystallites was found to be 20, 19, 15, and 10 nm when the volume percentage of PPE was 0.2, 0.4, 0.6, and 0.8%, respectively. TiO2 NPs obtained using PPE were coated on indium-doped tin oxide substrates and sensitized with natural dye made up of PPE and synthetic dyes, namely rose Bengal (RB) and eosin yellow (EY). The photoanode fabricated with dye-sensitized TiO2 NPs was subjected to current–voltage response studies. The maximum power-conversion efficiency, 1.4%, was recorded for photoanodes sensitized with PPE dye, which is considerably higher than that for RB (1.16%) or EY (0.8%). Overall, the above findings proved that PPE can be used as a potential reducing/capping agent and TiO2 sensitizer for DSSC applications.
New Approach to Improving the Efficiency of Disinfectants against Biofilms
Authors: Demkina Elena V. , Ilicheva Ekaterina A. , El-Registan Galina I. , Pankratov Timofey A. , Yushina Yulia K. , Semenova Anastasia A. , Nikolaev Yuriy A.
Published: March 2023

The resistance of microorganisms’ biofilms to antibacterials is a problem both for medicine and for many industries. Increasing the effectiveness of antimicrobial agents is an urgent task. The goal of the present work was to develop a new approach to development of anti-biofilm compositions based on conventional disinfectants in combination with enhancers (adjuvants). Methods of microbiology (viable cells count, model biofilms) and electron microscopy were employed. This research formulates the principles for selection of adjuvants. The adjuvants should: (1) increase the efficiency of decomposition of the biofilm matrix or/and (2) suppress the microbial protective mechanisms. For testing anti-biofilm compositions, two models of biofilms have been developed, on a solid surface at the interface with air or liquid. It was demonstrated that hydrogen peroxide, ethanol, isopropanol, and 4-hexylresorcinol enhanced the biocidal effect of disinfectants based on oxidants (peroxides and chlorine-containing) and quaternary ammonium salts by three to six orders of magnitude. Mechanisms of adjuvant action were mechanical decomposition of the matrix (by oxygen bubbles formed inside a biofilm in the case of hydrogen peroxide), coagulation of matrix polymers (in the case of alcohols), and a decrease in metabolism (in the case of 4-hexylresorcinol). The use of approved chemicals as adjuvants will accelerate the design of effective anti-biofilm antiseptics for medicine, social hygiene, and food manufactures and other industries.
Laboratory Assessment of Modified Asphalt Binders Using Crumb Rubber Modifier (CRM) and Processed Oil
Authors: Hemmati Navid , Vigneswaran Shyaamkrishnan , Mazumder Mithil , Lee Moon-Sup , Lee Soon-Jae
Published: March 2023

The study examines the effects of modifying PG 64-22 asphalt binder with Crumb Rubber Modifier (CRM) and processed oil on its properties. The binder was tested at different temperatures, and different amounts of CRM and processed oil were added to the binder. The modified binders were also aged using different procedures. The study found that adding processed oil to CRM-modified binders reduces viscosity and improves workability, while CRM improves the rutting resistance. However, the addition of processed oil reduces the binder’s rutting performance. The study also found that CRM and processed oil improve the low temperature cracking resistance. The study’s results indicate that co-modifying CRM binders with processed oil resulted in a significant reduction in viscosity values, resulting in improved workability. The results also showed that increasing the processed oil concentration from 6% to 12% caused a viscosity reduction of 27%, 34%, 33%, and 31% for modified binders containing 0, 5%, 10%, and 15% CRM, respectively. Even though the addition of processed oil results in a reduction in the rutting performance of asphalt binder, the addition of CRM significantly improved the rutting resistance of asphalt binders. The CRM binder containing processed oil decreased the G*sin δ values, and the content of 6% processed oil containing 5%, 10%, and 15% CRM decreased by 28%, 17%, and 11%, respectively, while the 12% processed oil-modified asphalt binder showed a reduction in G*sin δ by 5%, 13%, and 22%, respectively. The BBR results for modified asphalt binders showed that the incorporation of CRM and processed oil improved the low temperature cracking resistance significantly. The stiffness values with 6% processed oil containing 5%, 10%, and 15% CRM were observed to be 118, 97, and 80 MPa, respectively, while at the same temperature for the same CRM contents with 12% processed oil, the stiffness values were found to be 89, 72, and 56 MPa, respectively.
Models for Generation of Proof Forest in zk-SNARK Based Sidechains
Authors: Bespalov Yuri , Kovalchuk Lyudmila , Nelasa Hanna , Oliynykov Roman , Viglione Rob
Published: March 2023

Sidechains are among the most promising scalability and extended functionality solutions for blockchains. Application of zero knowledge techniques (Latus, Mina) allows for reaching high level security and general throughput, though it brings new challenges on keeping decentralization where significant effort is required for robust computation of zk-proofs. We consider a simultaneous decentralized creation of various zk-proof trees that form proof-trees sequences in sidechains in the model that combines behavior of provers, both deterministic (mutually consistent) or stochastic (independent) and types of proof trees. We define the concept of efficiency of such process, introduce its quantity measure and recommend parameters for tree creation. In deterministic cases, the sequences of published trees are ultimately periodic and ensure the highest possible efficiency (no collisions in proof creation). In stochastic cases, we obtain a universal measure of prover efficiencies given by the explicit formula in one case or calculated by a simulation model in another case. The optimal number of allowed provers’ positions for a step can be set for various sidechain parameters, such as number of provers, number of time steps within one block, etc. Benefits and restrictions for utilization of non-perfect binary proof trees are also explicitly presented.
A New Anti-Alias Model of Ab Initio Calculations of the Generalized Stacking Fault Energy in Face-Centered Cubic Crystals
Authors: Fan Dawei , Zhang Qingzhou , Fan Touwen , He Mengdong , Liu Linghong
Published: March 2023

The anti-alias model is an effective method to calculate the generalized stacking fault energy of the hexagonal close-packed crystals, but it has not been applied to the face-centered cubic crystals due to two different stacking faults occurring in the supercell during the sliding process. Based on the symmetry of these two stacking faults and the existing single analytic formula of the generalized stacking fault energy, we successfully extend the anti-alias model to compute the generalized stacking fault energy of face-centered cubic crystals, and the common fcc metals Al, Ni, Ag and Cu are taken as specific examples to illustrate the computational details. Finally, the validity of the proposed model is verified by data comparison and analysis. It is suggested that the anti-alias model is a good choice for the researchers to obtain more accurate generalized stacking fault energy of face-centered cubic metals.
Comparative Study on Gemmological Characteristics and Luminescence of Colorless and Yellow Scapolites
Authors: Rao Yinghua , Guo Qingfeng , Zhang Sixue , Liao Libing
Published: March 2023

The orange fluorescence of scapolite has been confirmed to be caused by (S2)−, but the frequent blue fluorescence in gem-quality scapolite has not been well explained. An energy dispersive X-ray fluorescence spectrometer (XRF), electron probe microanalyzer (EPMA), X-ray powder diffractometer (XRD), Fourier transform infrared spectrometer (FTIR), Raman spectrometer, ultraviolet-visible spectrophotometer, fluorescence spectrometer, and conventional gemological test methods were used to study the gemological characteristics, chemical composition, coloration mechanism, spectral characteristics, and luminescence of colorless and yellow scapolite. The results show that both yellow and colorless scapolites are mizzonite and that they share the same gemological and spectroscopic characteristics. The results of XRD, FIRT, and Raman spectra show that the yellow scapolite has the same structure as the colorless scapolite. The yellow color of scapolite is caused by Fe3+ and when the Fe content is low it is colorless. Yellow scapolite has about three times the Fe content of colorless scapolite. Under the excitation of long-wave and short-wave ultraviolet light, scapolite forms a strong and wide excitation peak in the blue-violet region centered at approximately 410 nm, which is due to the 4f1 → 5d1 of Ce3+, resulting in blue fluorescence.
Assessing the Influence of Anthropogenic Land-Use Changes on Bird Diversity and Feeding Guilds—A Case Study of Kalametiya Lagoon (Southern Sri Lanka)
Authors: Bernard Tom , Kodikara K. A. S. , Sleutel Jani , Wijeratne G. G. N. K. , Hugé Jean , Kumara M. P. , Weerasinghe M. A. Y. N. , Ranakawa D. P. D. , Thakshila W. A. K. G. , Dahdouh-Guebas Farid
Published: March 2023

Kalametiya Lagoon, a highly threatened Sri Lankan wetland, has undergone drastic hydrological changes in recent decades, due to an upstream irrigation project. These changes led to the invasion of the lagoon water by monospecific Sonneratia caseolaris mangrove stands and Typha angustifolia reedbeds. As Kalametiya has been a nationally recognized bird sanctuary since 1984, this invasion is expected to have brought significant changes upon local avifauna. Therefore, this study aimed at determining the lagoon’s current bird diversity and distribution in relation with habitat types and environmental variables. Thirty-seven point-count stations were studied, between January and April 2022. Seventy-nine bird species, including four endemic and ten nationally threatened species, were encountered during the study period. Invertebrate feeders and polyphages were the richest and most diverse guilds. Bird communities were also found richer and more diverse in T. angustifolia reedbeds than in S. caseolaris mangroves. As feeding guild composition was significantly influenced by several environmental variables (i.e., water nitrate content, water TDS, water pH, soil pH), guilds could have great potential as bioindicators of the ecosystem if further studies are done to explore these relationships. Considering the important bird diversity found in the new habitats, this research brings additional proof that a management aiming at restoring the lagoon to its past state would bring significant changes to its avifaunal community. These changes could, in the future, be more precisely defined by a thorough comparison with past inventories of the lagoon’s bird community.
A Synoptic Review of the Cartilaginous Fishes (Chondrichthyes: Holocephali, Elasmobranchii) from the Upper Jurassic Konservat-Lagerstätten of Southern Germany: Taxonomy, Diversity, and Faunal Relationships
Authors: Villalobos-Segura Eduardo , Stumpf Sebastian , Türtscher Julia , Jambura Patrick , Begat Arnaud , López-Romero Faviel , Fischer Jan , Kriwet Jürgen
Published: March 2023

The Late Jurassic-Early Cretaceous (164–100 Ma) represents one of the main transitional periods in life history. Recent studies unveiled a complex scenario in which abiotic and biotic factors and drivers on regional and global scales due to the fragmentation of Pangaea resulted in dramatic faunal and ecological turnovers in terrestrial and marine environments. However, chondrichthyan faunas from this interval have received surprisingly little recognition. The presence of numerous entire skeletons of chondrichthyans preserved in several localities in southern Germany, often referred to as Konservat-Lagerstätten (e.g., Nusplingen and the Solnhofen Archipelago), provides a unique opportunity of to study the taxonomic composition of these assemblages, their ecological distributions and adaptations, and evolutionary histories in detail. However, even after 160 years of study, the current knowledge of southern Germany’s Late Jurassic chondrichthyan diversity remains incomplete. Over the last 20 years, the systematic study and bulk sampling of southern Germany’s Late Jurassic deposits significantly increased the number of known fossil chondrichthyan genera from the region (32 in the present study). In the present work, the fossil record, and the taxonomic composition of Late Jurassic chondrichthyans from southern Germany are reviewed and compared with several contemporaneous assemblages from other sites in Europe. Our results suggest, inter alia, that the Late Jurassic chondrichthyans displayed extended distributions within Europe. However, it nevertheless also is evident that the taxonomy of Late Jurassic chondrichthyans is in urgent need of revision.
Key Members of the CmPn as Biomarkers Distinguish Histological and Immune Subtypes of Hepatic Cancers
Authors: Abou-Fadel Johnathan , Reid Victoria , Le Alexander , Croft Jacob , Zhang Jun
Published: March 2023

Liver cancer, comprising hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), is a leading cause of cancer-related deaths worldwide. The liver is a primary metabolic organ for progesterone (PRG) and PRG exerts its effects through classic nuclear PRG receptors (nPRs) and non-classic membrane PRG receptors (mPRs) or a combination of both. Previous studies have shown that the CCM signaling complex (CSC) couples both nPRs and mPRs to form the CmPn (CSC-mPR-PRG-nPR) signaling network, which is involved in multiple cellular signaling pathways, including tumorigenesis of various cancers. Despite advances in treatment, 5-year survival rates for liver cancer patients remain low, largely due to the chemoresistant nature of HCCs. The lack of sensitive and specific biomarkers for liver cancer diagnosis and prognosis emphasizes the need for identifying new potential biomarkers. We propose the potential use of CmPn members’ expression data as prognostic biomarkers or biomarker signatures for the major types of hepatic cancer, including HCCs and CCAs, as well as rare subtypes such as undifferentiated pleomorphic sarcoma (UPS) and hepatic angiosarcoma (HAS). In this study, we investigated the CmPn network through RNAseq data and immunofluorescence techniques to measure alterations to key cancer pathways during liver tumorigenesis. Our findings reveal significant differential expression of multiple CmPn members, including CCM1, PAQR7, PGRMC1, and nPRs, in both HCCs and CCAs, highlighting the crucial roles of mPRs, nPRs, and CSC signaling during liver tumorigenesis. These key members of the CmPn network may serve as potential biomarkers for the diagnosis and prognosis of liver cancer subtypes, including rare subtypes.
Antibiotic Resistance Diagnosis in ESKAPE Pathogens—A Review on Proteomic Perspective
Authors: Kalpana Sriram , Lin Wan-Ying , Wang Yu-Chiang , Fu Yiwen , Lakshmi Amrutha , Wang Hsin-Yao
Published: March 2023

Antibiotic resistance has emerged as an imminent pandemic. Rapid diagnostic assays distinguish bacterial infections from other diseases and aid antimicrobial stewardship, therapy optimization, and epidemiological surveillance. Traditional methods typically have longer turn-around times for definitive results. On the other hand, proteomic studies have progressed constantly and improved both in qualitative and quantitative analysis. With a wide range of data sets made available in the public domain, the ability to interpret the data has considerably reduced the error rates. This review gives an insight on state-of-the-art proteomic techniques in diagnosing antibiotic resistance in ESKAPE pathogens with a future outlook for evading the “imminent pandemic”.
Cone-Beam Computed Tomography as a Prediction Tool for Osteoporosis in Postmenopausal Women: A Systematic Literature Review
Authors: Isayev Abulfaz , Velieva Nigiar , Isedisha Luljeta , Isayeva Zhala , Kamburoğlu Kıvanç , Kuyumcu Fatih
Published: March 2023

This literature review was conducted to analyze the capability of cone-beam computed tomography (CBCT) to accurately identify low bone mass density in women. A systematic search of MEDLINE, Embase, Scopus, Google Scholar, the Cochrane Library, and Science Direct was performed to identify relevant articles, and the Cochrane risk of bias criterion was used to determine the methodological quality of the included studies. All ten included studies assessed primary research on the capacity of CBCT to accurately diagnose insufficient bone mineral density. All relevant data were extracted, and the results were summarized narratively. The results indicated that the CBCT has good sensitivity and specificity and high accuracy in predicting osteoporosis. Four of the included studies measured qualitative values, while the others concentrated on quantitative values and found lower values in osteoporosis patients compared to those of osteopenic and healthy patients. All the studies compared CBCT grayscale values with dual energy X-ray absorptiometry scores, which strengthened our confidence in the accuracy of CBCT’s diagnostic capability. CBCT is considered a feasible predictive tool for detecting patients who are at risk of osteoporosis, although further research is needed to confirm the evidence and enhance its common use among health care professionals.
Multi-Perspective Investigations Based Design Framework of an Electric Propulsion System for Small Electric Unmanned Aerial Vehicles
Authors: Kulanthipiyan Surenther , Rajendran Parvathy , Raja Vijayanandh
Published: March 2023

Numerous attempts have been made to extend the endurance of small unmanned aerial vehicles (UAVs) by improving their propulsion system. However, due to their non-linear setup, no study has been conducted on small electric UAVs’ architecture framework. This study established a novel propulsion system framework model by analyzing 42 existing UAV electric propulsion systems. The proposed framework-based complicated model includes a new torque factor used to determine the operating current and voltage of the system. This innovative approach improved the model accuracy for the non-linear behavioral nature-based electrical and mechanical systems. The findings include a reduced electrical current usage of up to 84% and an average reduction of 26%. In addition, the investigation also found that the durability of the propulsion systems improved by 53% on average. Similarly, improvements in the trust-to-weight ratio were also established. As a result, a method of propeller matching is presented to facilitate the broad implementation of the proposed framework. The performance of the existing propulsion system was enhanced by using the proposed framework.
A Method Based on Timing Weight Priority and Distance Optimization for Quantum Circuit Transformation
Authors: Qian Yang , Guan Zhijin , Zheng Shenggen , Feng Shiguang
Published: March 2023

In order to implement a quantum circuit on an NISQ device, it must be transformed into a functionally equivalent circuit that satisfies the device’s connectivity constraints. However, NISQ devices are inherently noisy, and minimizing the number of SWAP gates added to the circuit is crucial for reducing computation errors. To achieve this, we propose a subgraph isomorphism algorithm based on the timing weight priority of quantum gates, which provides a better initial mapping for a specific two-dimensional quantum architecture. Additionally, we introduce a heuristic swap sequence selection optimization algorithm that uses a distance optimization measurement function to select the ideal sequence and reduce the number of SWAP gates, thereby optimizing the circuit transformation. Our experiments demonstrate that our proposed algorithm is effective for most benchmark quantum circuits, with a maximum optimization rate of up to 43.51% and an average optimization rate of 13.51%, outperforming existing related methods.
Modeling to Correct the Effect of Soil Moisture for Predicting Soil Total Nitrogen by Near-Infrared Spectroscopy
Authors: Tang Rongnian , Jiang Kaixuan , Li Chuang , Li Xiaowei , Wu Jingjin
Published: March 2023

Near-infrared (NIR) spectroscopy can improve the efficiency of soil property prediction, such as that of soil total nitrogen (TN) content. However, soil spectra are very sensitive to soil moisture content, which is a crucial factor affecting the accuracy of soil nutrient composition prediction. In response to this issue, the goal of this study is to identify the best model to correct the effect of soil moisture for predicting soil total nitrogen by near-infrared spectroscopy. The 107 collected soil samples were divided into six different water content (0%, 5%, 10%, 15%, 20%, and 25%) sample groups. Then, five correction methods, including direct standardization (DS), piecewise direct standardization (PDS), external parameter orthogonalization (EPO), spectral space transformation (SST), and slope/bias (S/B), were executed. Finally, partial least squares regression (PLSR) models were established to forecast TN content. The results showed that SST could minimize the influence of moisture. Furthermore, SST–PLSR had the best TN content prediction accuracy: Rp2 (the coefficient of determination of the prediction set) in the range of 0.81–0.82, RMSEP (the root mean square error of the prediction set) in the range of 0.09–0.10 g/kg, and RPD (ratio of performance to deviation) in the range of 2.32–2.40. Therefore, the dry soil prediction model is competent for wet soil samples and could achieve preciseness in TN content prediction. The use of SST can effectively eliminate the influence of moisture and achieve high-precision TN prediction in wet soil samples. Additionally, the introduction of SST expands the application scope of soil nutrient prediction models and increases model robustness.
Knowledge Acquisition and Reasoning Model for Welding Information Integration Based on CNN and Knowledge Graph
Authors: Guan Kainan , Sun Yang , Yang Guang , Yang Xinhua
Published: March 2023

Knowledge acquisition and reasoning are essential in intelligent welding decisions. However, the challenges of unstructured knowledge acquisition and weak knowledge linkage across phases limit the development of welding intelligence, especially in the integration of domain information engineering. This paper proposes a cognitive model combining image recognition and a knowledge graph. A CNN is used as the perception layer to obtain direct information. Automated logic rules based on a knowledge graph are described to enable information integration in the knowledge reasoning domain. In addition, a welding knowledge graph of the bogie frame was constructed based on entity and relationship recognition. CNN models with different network structures were compared and trained under supervised conditions. In the results, the InceptionV1 network obtained a high score (0.758 for the thickness relation, 0.642 for the groove form, 0.704 for the joint type, and 0.835 for the base material form). The proposed model showed positive performance in terms of accuracy, interpretation, knowledge coverage, scalability, and portability compared with several other methods. The model can effectively address the abovementioned limitations and is important for welding manufacturing with engineering information integration.
Bluetooth Low Energy Beacon Powered by the Temperature Difference
Authors: Pyt Patryk , Jankowski-Mihułowicz Piotr , Węglarski Mariusz
Published: March 2023

Bluetooth low energy beacons are active transmitters that send a radio signal at set intervals. Most beacons are powered by small batteries. The problem with systems based on such devices is the need to periodically replace the chemical cells. This is especially tedious when a large number of the beacons is used. The maintenance of such a system causes several serious problems related to the high cost of new batteries and their replacement, time-consuming service and environmental pollution. A solution to these problems is to use beacons with a power supply supported by photovoltaic panels. Their obvious drawback is the need to place them in good lighting conditions. To overcome this disadvantage, the use of a power source that gathers energy due to the Peltier effect is proposed in this paper. Since the temperature difference between two surfaces can be found in almost every environment, the authors analyzed the efficiency of this kind of energy source in the context of powering the beacons. In order to justify the idea, a multitude of measurements and simulations was performed. The power supply demand of the beacon was measured in various modes of operation. The Peltier module was examined at different loads and various temperature differences. On the basis of the gathered data, the energy conditioning system was defined for a given temperature difference sufficient to power the beacon. Finally, the model of the proposed device was developed. The elaborated solution eliminates the need for batteries and makes the beacon maintenance-free.
Consensus of Fixed and Adaptive Coupled Multi-Agent Systems with Communication Delays
Authors: Qiu Zicheng , Tian Sheng , Zhou Baoping , Han Qi , Tian Yuan , Weng Tengfei , Mamut Turghunjan
Published: March 2023

This paper aims to solve the consensus problem of three different types of multi-agent systems under fixed communication delay. For these three different types of multi-agent systems, three new control protocols are constructed to solve the consensus issue of multi-agent systems with coupling weights, which is rarely considered in other related articles. For fixed coupled multi-agent systems, a new control strategy is designed by Lyapunov theory, matrix theory, and the inequality method to ensure the consensus of multi-agent systems. An adaptive coupling weight updating scheme is proposed for adaptive coupling multi-agent systems to achieve the consensus state of the multi-agent systems. Finally, experimental results show the effectiveness of the proposed three different algorithms.
An Experimental and Simulation Study for Comparison of the Sensitivity of Different Non-Destructive Capacitive Sensors in a Stratified Two-Phase Flow Regime
Authors: Shahsavari Mohammad Hossein , Veisi Aryan , Roshani Gholam Hossein , Eftekhari-Zadeh Ehsan , Nazemi Ehsan
Published: March 2023

Measuring the volume fraction of each phase in multi-phase flows is an essential problem in petrochemical industries. One of the standard flow regimes is stratified two-phase flow, which occurs when two immiscible fluids are present in a pipeline. In this paper, we performed several experiments on vertical concave, horizontal concave, and double-ring sensors to benchmark obtained simulation results from modeling these sensors in stratified two-phase flow using COMSOL Multiphysics software. The simulation data was confirmed by experimental data. Due to the low number of data in the experimental method in order to extract more data, the mentioned software was used to extract more data and then compare the sensitivity of different directions of concave and double ring sensors. The simulation results show that the overall sensitivity of the concave is higher than the double-ring and the momentary sensitivity of the horizontal concave is higher in higher void fractions, and the vertical one has higher sensitivity in lower void fractions.
Definition of Regulatory Targets for Electricity Non-Technical Losses: Proposition of an Automatic Model-Selection Technique for Panel Data Regressions
Authors: Correia Eduardo , Calili Rodrigo , Pessanha José Francisco , Almeida Maria Fatima
Published: March 2023

Non-technical losses (NTLs) are one of the main problems that electricity distribution utilities face in developing regions such as Latin America, the Caribbean, sub-Saharan Africa, and South Asia. Particularly in Brazil, based on the socioeconomic and market variables concerning all the distribution utilities, the National Electric Energy Agency (ANEEL) has formulated several specifications of econometric models for panel data with random effects, all aimed at determining an index that reflects the difficulty of combating NTLs according to the intrinsic characteristics of each distribution area. Nevertheless, given the exhaustive search for combinations of explanatory variables and the complexity inherent to defining regulatory NTL targets, this process still requires the evaluation of many models through hypothesis and goodness-of-fit tests. In this regard, this article proposes an automatic model-selection technique for panel data regressions to better assist the Agency in establishing NTL regulatory targets for the distribution of utilities in this country. The proposed technique was applied to panel data containing annual observations from 62 Brazilian electricity distribution utilities from 2007 to 2017, thus generating 1,097,789 models associated with the regression types in the panel data. The main results are three selected models that showed more adherence to the actual capacity of Brazilian distribution utilities to reduce their NTLs.
Modeling and Simulation of Crude Oil Sea–River Transshipment System in China’s Yangtze River Basin
Authors: Yang Yan , Zhou Qiang
Published: March 2023

China’s Yangtze River Basin has an increasingly strong demand for crude oil. As a seaborne import port for crude oil, Ningbo-Zhoushan Port is under pressure to undertake the transshipment of crude oil to various oil terminals in the Yangtze River Basin. To alleviate the stress of crude oil transportation in Ningbo-Zhoushan Port, the port operator proposed the crude oil sea–river transshipment scheme in Nantong Port. Therefore, this paper aims to verify the feasibility of this scheme. We used the discrete event system modeling and entity relationship diagram method to construct the hierarchical and concept models of the Yangtze River Basin’s crude oil sea–river transportation system. Furthermore, we developed corresponding simulation modules on the Witness platform and carried out a simulation experiment of the crude oil sea–river transfer scheme. In the experiment, we analyzed the influence of the transshipment ratio on berth utilization, waiting time, and sailing time of other ports by adjusting the parameter of the transshipment ratio. The experimental results show that when the transshipment rate reaches 100%, the utilization rates of loading and unloading berth in Nantong Port are 4% and 13%, respectively, which evidences that Nantong Port has transshipment potential. At the same time, the simulation experiment’s statistical indicators, such as the utilization rate of oil berths, the queuing time of oil tankers, and the sailing time, not only confirm the feasibility of the crude oil sea–river transshipment scheme of Nantong Port but also confirm that the scheme is helpful to improve crude oil transportation efficiency. The simulation results benefit the port operation decision, and the established model and simulation module can be encapsulated and reused.
Simulation of Series Resistance Increase through Solder Layer Cracking in Si Solar Cells under Thermal Cycling
Authors: Han Changwoon
Published: March 2023

In solar cell modules, thermal cycling stresses can cause cracking in the ribbon wire, leading to an increase in series resistance and a drop in the power output of the module. Quantitative analysis was conducted to study the increase in series resistance, considering two cracking models: continuous and random. In the continuous model, it was expected that if all the ribbon wires on the front side of the module cracked, the current would decrease linearly from 0 to 100%, and the series resistance would increase exponentially to infinity. In the random crack model, the current dropped slowly, and the series resistance increased less compared with that in the continuous one. A mathematical model based on the bypass mechanism of the currents was proposed to explain the differences between the two models. The study found that cracking in the solder layer under thermal cycling can be described by a combination of continuous and random models, which can represent the upper and lower levels of the series resistance increase. When the solar cell power dropped to 80%, the increase in series resistance was expected to be in the range of 200 to 250% using the continuous and random models, respectively.
New Method for State Express Control of Unstable Hydrocarbon Media and Their Mixtures
Authors: Davydov Vadim , Vakorina Darya , Provodin Daniil , Ryabogina Natalya , Stepanenkov Gregory
Published: March 2023

All requirements for the express control of unstable hydrocarbon media and devices for their implementation to obtain reliable measurement results are determined. The features of the control of volatile hydrocarbon media and their mixtures with industrial small-sized refractometers operating on the effect of total internal reflection are considered. The new method for determining components and the ratio between concentrations of them in a mixture of volatile hydrocarbon media is developed. There are no analogs to this method in the world. This method allows determining the presence of one volatile hydrocarbon medium in another in a ratio of 1% to 99% or more. The new design of a small-sized refractometer has been developed, which makes it possible to measure the refractive index in visible light. In the refractometer’s newly developed design, the refractive index measurement range of a condensed medium is from 1.2500 to 1.7000 (measurement error 0.0004). New dependencies of change in density ρ for various grades of hydrocarbon fuel (in the Russian Federation) on temperature T have been established. After adjusting the coefficients, these dependencies can be used for fuel produced in various world countries. The results of the research on different gasoline types and their mixtures are presented.
Estimating Sustainable Long-Term Fluid Disposal Rates in the Alberta Basin
Authors: Samaroo Mahendra , Chalaturnyk Rick , Dusseault Maurice
Published: March 2023

Reliable regional-scale permeability data and minimum sustained injectivity rate estimates are key parameters required to mitigate economic risk in the site selection, design, and development of commercial-scale carbon sequestration projects, but are seldom available. We used extensive publicly available disposal well data from over 4000 disposal wells to assess and history-match regional permeability estimates and provide the frequency distribution for disposal well injection rates in each of 66 disposal formations in the Alberta Basin. We then used core data and laboratory analyses from over 3000 cores to construct 3D geological, geomechanical and petrophysical models for 22 of these disposal formations. We subsequently used these models and the history-matched regional permeability estimates to conduct coupled geomechanical and reservoir simulation modeling (using the ResFrac™, Palo Alto, CA, USA, numerical simulator) to assess: (i) well performance in each formation when injecting carbon dioxide for a 20-year period; (ii) carbon dioxide saturation and reservoir response at the end of the 20-year injection period; (iii) reliability of our simulated rates compared to an actual commercial sequestration project. We found that: (i) the injection rate from our simulations closely matched actual performance of the commercial case; (ii) only 7 of the 22 disposal formations analyzed appeared capable of supporting carbon dioxide injectors operating at greater than 200,000 tons per year/well; (iii) three of these formations could support injectors operating at rates comparable to the successful commercial-scale case; (iv) carbon dioxide presence and a formation pressure increase of at least 25% above pre-injection pressure can be expected at the boundaries of the (12 km × 12 km) model domain at the end of 20 years of injection.
A Comprehensive Study on Effect of Biofuel Blending Obtained from Hydrothermal Liquefaction of Olive Mill Waste Water in Internal Combustion Engine
Authors: Aklouche Fatma Zohra , Hadhoum Loubna , Loubar Khaled , Tazerout Mohand
Published: March 2023

The production of biofuel from olive mill wastewater (OMWW) may be one of the promising techniques for use in diesel engines. In this study, biofuel was produced from the hydrothermal liquefaction of OMWW using a methanol-water co-solvent. Biofuel blends of 10% (B10), 20% (B20) and 30% (B30) by volume of biofuel, were prepared. The chemical and physical properties of biofuel blends are mostly similar to those of conventional diesel fuel. The engine speed was kept constant (1500 rpm) throughout the tests under different engine loads (25, 50, 75 and 100%). The effects of biofuel-diesel blends on exhaust emissions and engine performance were investigated. The results show that the in-cylinder pressure follows almost the same trend for all fuels. However, at high loads, with increasing biofuel blend, the combustion duration tends to become longer. The B10 blend provided close results to diesel fuel in terms of performance and polluting emissions. Moreover, the use of B10 resulted in reduced emission levels, with 11% of unburned hydrocarbons, 12% of particles and 26% of carbon dioxide compared to the other blends.
Study on the Extensibility of Voltage-Plateau-Based Lithium Plating Detection for Electric Vehicles
Authors: Somasundaran Nithin , Fereshteh Saniee Nessa , Dinh Truong Quang , Marco James
Published: March 2023

Lithium plating is an undesirable side reaction in lithium-ion cells during fast charging at lower temperatures. The voltage plateau of the open-circuit voltage (OCV) of cells after charging is widely used to infer the onset of lithium plating. The differential analysis of post-charge OCV has been shown to yield greater insights into the Li stripping characteristics. Though this method is continuously evaluated for single cells in open circuit, a battery module can have a series and parallel connection of cells. The effectiveness and scalability of the voltage-plateau-based technique for battery modules is presented here. The study focuses on individual cells in open circuit, cells in parallel connection, and cells in a series-parallel connection. The results validate the scalability of the technique, yet the reliability and sensitivity were observed to be inferior to the single cell results published previously.
Electricity Prices in the European Union Region: The Role of Renewable Energy Sources, Key Economic Factors and Market Liberalization
Authors: Halkos George E. , Tsirivis Apostolos S.
Published: March 2023

Electricity is by far the most valuable energy commodity for households; hence, it is of the utmost importance for national regulatory authorities and the European Commission (EC) to guarantee affordable and unimpeded access for European citizens to this vital social good. The existing academic literature mainly focuses on the effect of specific renewable energy resources (RES), such as solar, wind, etc., on electricity prices, thus neglecting the crucial impact of the electricity market structure. In an effort to fill this gap, the present paper attempts to clarify whether the real effect of the share of total renewable energy production in the generation scheme and certain electricity market liberalization indices constitute key determinants of household electricity prices. The study is further innovative on the grounds that the empirical analysis utilizes both static and dynamic panel methodologies for a dataset including several variables introduced for the first time in academia. The dataset consists of yearly observations regarding 26 EU countries for a time horizon from 2003 until 2019. The econometric outcomes revealed the complex relationship between RES deployment and generation concentration with the level of household electricity prices. In contrast, the deregulation of the retail market and especially the presence of many retailers with a market share exceeding 5% can benefit European consumers by reducing electricity prices. Additionally, the relative costs concerning the outward-orientation of the economy and the power system’s upgrade were found to be transferred to the final electricity price. The opposite applies to environmental taxes, allowing European governments to accumulate considerable funds for ecological and environmental protection actions. Lastly, due to the estimated slow adjustment rate of electricity prices, policymakers are advised to develop long-term strategic energy planning.
Power Production and Blade Fatigue of a Wind Turbine Array Subjected to Active Yaw Control
Authors: Lin Mou , Porté-Agel Fernando
Published: March 2023

This study investigated the power production and blade fatigue of a three-turbine array subjected to active yaw control (AYC) in full-wake and partial-wake configurations. A framework of a two-way coupled large eddy simulation (LES) and an aeroelastic blade simulation was applied to simulate the atmospheric boundary layer (ABL) flow through the turbines and the structural responses of the blades. The mean power outputs and blade fatigue loads were extracted from the simulation results. By exploring the feasible AYC decision space, we found that in the full-wake configuration, the local power-optimal AYC strategy with positive yaw angles endures less flapwise blade fatigue and more edgewise blade fatigue than the global power-optimal strategy. In the partial-wake configuration, applying positive AYC in certain inflow wind directions achieves higher optimal power gains than that in the full-wake scenario and reduces blade fatigue from the non-yawed benchmark. Using the blade element momentum (BEM) theory, we reveal that the aforementioned differences in flapwise blade fatigue are due to the differences in the azimuthal distributions of the local relative velocity on blade sections, resulting from the vertical wind shear and blade rotation. Furthermore, the difference in the blade force between the positively and negatively yawed front-row turbine induces different wake velocities and turbulence distributions, causing different fatigue loads on the downwind turbine exposed to the wake.
Probabilistic Power Flow Method for Hybrid AC/DC Grids Considering Correlation among Uncertainty Variables
Authors: Xia Xiaotian , Xiao Liye
Published: March 2023

For a new power system using high-penetration renewable energy, the traditional deterministic power flow analysis method cannot accurately represent the stochastic characteristics of each state variable. The aggregation of renewable energy with different meteorological characteristics in the AC/DC interconnected grid significantly increases the difficulty of establishing a steady-state model. Therefore, this study proposes an improved Latin hypercube sampling algorithm using the van der Waerden scores and diffusion kernel density estimation to overcome the limitations of a priori assumption on probability distributions in uncertainty modeling and to retain the correlations among random variables in the sampling data. Interconnected grids are constructed with IEEE 9-bus and IEEE 14-bus and modified with IEEE 57-bus to describe common application cases of aggregated renewable energy. On this basis, the approximation errors of the proposed probabilistic power flow algorithm to the statistical characteristics of the power parameters are evaluated by setting the Nataf algorithm and the Latin hypercube algorithm using adaptive kernel density estimation as the control group. The results show that the improved Latin hypercube sampling algorithm can exhibit high computational accuracy and strong adaptability, both in severe operating scenarios with large amplitude of load fluctuations and with nonlinear power balance equations incorporating high dimensional random variables.