bluuebunny/crossref_metadata_2025 huggingface dataset:
A New Geomagnetic Vector Navigation Method Based on a Two-Stage Neural Network
Authors: Chen Zhuo , Liu Zhongyan , Zhang Qi , Chen Dixiang , Pan Mengchun , Xu Yujing
Published: April 2023

The traditional geomagnetic matching navigation method is based on the correlation criteria operations between measurement sequences and a geomagnetic map. However, when the gradient of the geomagnetic field is small, there are multiple similar data in the geomagnetic database to the measurement value, which means the correlation-based matching method fails. Based on the idea of pattern recognition, this paper constructs a two-stage neural network by cascading a probabilistic neural network and a non-fully connected neural network to, respectively, classify geomagnetic vectors and their feature information in two steps: “coarse screening” and “fine screening”. The effectiveness and accuracy of the geomagnetic vector navigation algorithm based on the two-stage neural network are verified through simulation and experiments. In simulation, it is verified that when the geomagnetic average gradient is 5 nT/km, the traditional geomagnetic matching method fails, while the positioning accuracy based on the proposed method is 40.17 m, and the matching success rate also reaches 98.13%. Further, in flight experiments, under an average gradient of 11 nT/km, the positioning error based on the proposed method is 39.01 m, and the matching success rate also reaches 99.42%.
Unsupervised Numerical Information Extraction via Exploiting Syntactic Structures
Authors: Wang Zixiang , Li Tongliang , Li Zhoujun
Published: April 2023

Numerical information plays an important role in various fields such as scientific, financial, social, statistics, and news. Most prior studies adopt unsupervised methods by designing complex handcrafted pattern-matching rules to extract numerical information, which can be difficult to scale to the open domain. Other supervised methods require extra time, cost, and knowledge to design, understand, and annotate the training data. To address these limitations, we propose QuantityIE, a novel approach to extracting numerical information as structured representations by exploiting syntactic features of both constituency parsing (CP) and dependency parsing (DP). The extraction results may also serve as distant supervision for zero-shot model training. Our approach outperforms existing methods from two perspectives: (1) the rules are simple yet effective, and (2) the results are more self-contained. We further propose a numerical information retrieval approach based on QuantityIE to answer analytical queries. Experimental results on information extraction and retrieval demonstrate the effectiveness of QuantityIE in extracting numerical information with high fidelity.
A Cascade Network for Blind Recognition of LDPC Codes
Authors: Zhang Xiang , Zhang Wei
Published: April 2023

Coding blind recognition plays a vital role in non-cooperative communication. Most of the algorithm for coding blind recognition of Low Density Parity Check (LDPC) codes is difficult to apply and the problem of high time complexity and high space complexity cannot be solved. Inspired by deep learning, we propose an architecture for coding blind recognition of LDPC codes. This architecture concatenates a Transformer-based network with a convolution neural network (CNN). The CNN is used to suppress the noise in real time, followed by a Transformer-based neural network aimed to identify the rate and length of the LDPC codes. In order to train denoise networks and recognition networks with high performance, we build our own datasets and define loss functions for the denoise networks. Simulation results show that this architecture is able to achieve better performance than the traditional method at a lower signal-noise ratio (SNR). Compared with the existing methods, this approach is more flexible and can therefore be quickly deployed.
A High Conversion Ratio DC–DC Boost Converter with Continuous Output Current Using Dual-Current Flows
Authors: Kim Hwa-Soo , Shin Se-Un
Published: April 2023

Recently, the demand for small, low-cost electronics has increased the use of cost-effective tiny inductors in power-management ICs (PMICs). However, the conduction loss caused by the parasitic DC resistance (RDCR) of a small inductor leads to low efficiency, which reduces the battery usage time and may also cause thermal problems in mobile devices. In particular, these issues become critical when a conventional boost converter (CBC) is used to achieve high-output voltage due to the large inductor current. In addition, as the output voltage increases, a number of issues become more serious, such as large output voltage ripple, conversion-ratio limit, and overlap loss. To solve these issues, this paper proposed a high-voltage boost converter with dual-current flows (HVDF). The proposed HVDF can achieve a higher efficiency than a CBC by reducing the total conduction loss in heavy load current conditions with a small inductor. Moreover, because in the HVDF, the current delivered to the output becomes continuous, unlike in the CBC with its discontinuous output delivery current, the output voltage ripple can be significantly reduced. Also, the conversion gain of the HVDF is less sensitive to RDCR than that of the CBC. To further increase the conversion gain, a time-interleaved charge pump can be connected in series with the HVDF (HVDFCP) to achieve higher output voltage beyond the limit of the conversion gain in the HVDF while maintaining the advantages of a low inductor current and small output voltage ripple. Simulations using PSIM were performed along with a detailed numerical analysis of the conduction losses in the proposed structures. The simulation results were discussed and compared with those of the conventional structures.
Improving Ecological Efficiency of Gas Turbine Power System by Combusting Hydrogen and Hydrogen-Natural Gas Mixtures
Authors: Serbin Serhiy , Radchenko Mykola , Pavlenko Anatoliy , Burunsuz Kateryna , Radchenko Andrii , Chen Daifen
Published: April 2023

Currently, the issue of creating decarbonized energy systems in various spheres of life is acute. Therefore, for gas turbine power systems including hybrid power plants with fuel cells, it is relevant to transfer the existing engines to pure hydrogen or mixtures of hydrogen with natural gas. However, significant problems arise associated with the possibility of the appearance of flashback zones and acoustic instability of combustion, an increase in the temperature of the walls of the flame tubes, and an increase in the emission of nitrogen oxides, in some cases. This work is devoted to improving the efficiency of gas turbine power systems by combusting pure hydrogen and mixtures of natural gas with hydrogen. The organization of working processes in the premixed combustion chamber and the combustion chamber with a sequential injection of ecological and energy steam for the “Aquarius” type power plant is considered. The conducted studies of the basic aerodynamic and energy parameters of a gas turbine combustor working on hydrogen-containing gases are based on solving the equations of conservation and transfer in a multicomponent reacting system. A four-stage chemical scheme for the burning of a mixture of natural gas and hydrogen was used, which allows for the rational parameters of environmentally friendly fuel burning devices to be calculated. The premixed combustion chamber can only be recommended for operations on mixtures of natural gas with hydrogen, with a hydrogen content not exceeding 20% (by volume). An increase in the content of hydrogen leads to the appearance of flashback zones and fuel combustion inside the channels of the swirlers. For the combustion chamber of the combined-cycle power plant “Vodoley”, when operating on pure hydrogen, the formation of flame flashback zones does not occur.
Improving Thermal Stability of Perovskite Solar Cells by Thermoplastic Additive Engineering
Authors: Uddin Zaheen , Ran Junhui , Stathatos Elias , Yang Bin
Published: April 2023

The commercialization of perovskite solar cells is hindered by the poor thermal stability of organic–inorganic hybrid perovskite materials. Herein, we demonstrate that crystalline thermoplastic polymer additives, such as a mixture of polyethylene oxide (PEO, 100,000 MW) and polyethylene glycol (PEG, 12,000 MW), can improve the thermal stability of CH3NH3PbI3 (MAPbI3) perovskites and thereby enhance device stability. High-quality less-defect perovskite films were obtained by establishing a strong reaction between hydroxy groups in the PEO + PEG mixture and the uncoordinated Pb2+ in MAPbI3 perovskites, leading to a high power conversion efficiency of over 18% despite the presence of insulating thermoplastic polymers in the MAPbI3 film. More importantly, as compared with pristine MAPbI3 perovskite solar cells, the PEO + PEG-modified counterparts showed significantly improved stability under thermal treatment at 85 °C in ambient air with a relative humidity of 50–60%, remaining at nearly 71% of their initial efficiency values after 120 h. These demonstrations offer a feasible thermoplastic polymer additive engineering strategy to improve the thermal stability of perovskite solar cells.
Grid-Tied Single-Phase Integrated Zeta Inverter for Photovoltaic Applications
Authors: Dionizio Anderson Aparecido , Sampaio Leonardo Poltronieri , da Silva Sérgio Augusto Oliveira , Machado Sebastián de Jesús Manrique
Published: April 2023

Recently, the development of integrated inverters for photovoltaic systems has been widely performed to reduce overall system size, costs, and losses. Thus, integrated inverters have emerged as a prominent solution for replacing two-stage power conversion composed of a step-up converter and a voltage source inverter. Thereby, this paper proposes an integrated inverter topology for single-phase grid-tied photovoltaic systems. The proposed power converter, called a Single-Phase Integrated Zeta Inverter (SP-IZI), can boost the input voltage and inject a sinusoidal and regulated current into the mains with low harmonic distortion. The SP-IZI is based on integrating modified DC-DC Zeta converters, designed and controlled to operate in a discontinuous conduction mode, and presents similarities with the Modified Zeta Inverter (MZI). In this way, this paper compares the main parameters of both topologies and provides a complete study of the SP-IZI, involving both quantitative and qualitative studies as well as a small signals analysis. The feasibility and functionality of the proposed SP-IZI inverter are presented and evaluated through experimental results, which demonstrate that the SP-IZI presents the following advantages compared to the MZI: (i) the voltage in coupling capacitors is 13% lower; (ii) voltage stresses in switches and diodes are 40% lower; and (iii) static gain is similar to the traditional Zeta converter.
Financial and Technical Evaluation of Energy Production by Biological and Thermal Treatments of MSW in Mexico City
Authors: Escamilla-García Pablo Emilio , Coria-Páez Ana Lilia , Pérez-Soto Francisco , Gutiérrez-Galicia Francisco , Caire Carolina , Martínez-Vargas Blanca L.
Published: April 2023

This research aims to compare, from a technical and financial perspective, the application of biological (methane-capture) and thermal (incineration) treatments of waste in Mexico City in order to generate clean energy. For each alternative, pessimist (50%), realistic (80%), and optimistic (100%) scenarios were considered in terms of the efficiency collection rates of methane and the efficiency of the capacity conversion factor for incineration. For the methane project, the LandGEM model was used to evaluate the potential generation of methane. In order to calculate the electricity output that could be generated through incineration, we relied on two key factors: the total amount of heat that could be generated by burning the waste and the average level of moisture in the waste material. The evaluation resulted in an annual energy generation of 206.09 GWh for methane and 4183.39 GWh for incineration, both in the realistic scenario. Both projects reported positive financial indicators with a discount rate of 12%. Incineration resulted in a net present value of USD 706,377,303 and an internal rate of return of 23% versus USD 4,975,369 and 24% for the methane project. However, the incineration project only became feasible by omitting financing. Incineration resulted in a payback period that was lower by a ratio of 2:1 compared to methane, but the levelized cost of energy resulted in higher figures (USD 216.92). The aim of these findings is to support the decision-making process for the creation and implementation of sustainable energy strategies based on circular economy principles in Mexico and other similar regions across the globe.
Power Quality Analysis Based on Machine Learning Methods for Low-Voltage Electrical Distribution Lines
Authors: Iturrino Garcia Carlos Alberto , Bindi Marco , Corti Fabio , Luchetta Antonio , Grasso Francesco , Paolucci Libero , Piccirilli Maria Cristina , Aizenberg Igor
Published: April 2023

The main objective of this paper is to propose two innovative monitoring methods for electrical disturbances in low-voltage networks. The two approaches present a focus on the classification of voltage signals in the frequency domain using machine learning techniques. The first technique proposed here uses the Fourier transform (FT) of the voltage waveform and classifies the corresponding complex coefficients through a multilayered neural network with multivalued neurons (MLMVN). In this case, the classifier structure has three layers and a small number of neurons in the hidden layer. This allows complex-valued inputs to be processed without the need for pre-coding, thus reducing computational cost and keeping training time short. The second technique involves the use of the short-time Fourier transform (STFT) and a convolutional neural network (CNN) with 2D convolutions in each layer for feature extraction and dimensionality reduction. The voltage waveform perturbations taken into consideration are: voltage sag, voltage swell, harmonic pollution, voltage notch, and interruption. The comparison between the two proposed techniques is developed in two phases: initially, the simulated data used during the training phase are considered and, subsequently, various experimental measurements are processed, obtained both through an artificial disturbance generator and through a variable load. The two techniques represent an innovative approach to this problem and guarantee excellent classification results.
A Comparative Study of the Kalman Filter and the LSTM Network for the Remaining Useful Life Prediction of SOFC
Authors: Sheng Chuang , Zheng Yi , Tian Rui , Xiang Qian , Deng Zhonghua , Fu Xiaowei , Li Xi
Published: April 2023

The solid oxide fuel cell (SOFC) system is complicated because the characteristics of gas, heat, and electricity are intricately coupled. During the operation of the system, problems such as frequent failures and a decrease in the stack’s performance have caused the SOFC system to work less well and greatly shortened the SOFC’s practical life. As such, it is essential to accurately forecast its remaining useful life (RUL) to make the system last longer and cut down on economic losses. In this study, both model-based and data-driven prediction methods are used to make predictions about the RUL of SOFC. First, the linear degradation model of the SOFC system is established by introducing degradation resistance as the index of health status. Using the Kalman filtering (KF) method, the health status of SOFC is evaluated online. The results of the health state estimation indicated that the KF algorithm is accurate enough to provide a good basis for the model-based RUL prediction. Then, a long short-term memory (LSTM) network-recursive (data-driven) method is presented for RUL prognostics. The multi-step-ahead recursive strategy of updating the network state with actual test data improves the prediction accuracy. Finally, a comparison is made between the LSTM network prediction approach suggested and the model-based KF prognostics. The results of the experiments indicate that the LSTM network is more suitable for RUL prediction than the KF algorithm.
Research on Optimization of Profile Parameters in Screw Compressor Based on BP Neural Network and Genetic Algorithm
Authors: Wang Tao , Qi Qiang , Zhang Wei , Zhan Dengyi
Published: April 2023

In order to accurately calculate the geometric characteristics of the twin-screw compressor and obtain the optimal profile parameters, a calculation method for the geometric characteristics of twin-screw compressors was proposed to simplify the profile parameter design in this paper. In this method, the database of geometric characteristics is established by back-propagation (BP) neural network, and the genetic algorithm is used to find the optimal profile design parameters. The effects of training methods and hidden layers on the calculation accuracy of neural network are discussed. The effects of profile parameters, including inner radius of the male rotor, protection angle, radius of the elliptic arc, outer radius of the female rotor on the comprehensive evaluation value composed of length of the contact line, blow hole area and area utilization rate, are analyzed. The results show that the time consumed for the database established by BP neural network is 92.8% shorter than that of the traditional method and the error is within 1.5% of the traditional method. Based on the genetic algorithm, compared with the original profile, the blow hole area of the screw compressor profile optimized by genetic algorithm is reduced by 54.8%, the length of contact line is increased by 1.57% and the area utilization rate is increased by 0.32%. The CFD numerical model is used to verify the optimization method, and it can be observed that the leakage through the blow hole of the optimized model is reduced, which makes the average mass flow rate increase by 5.2%, indicating the effectiveness of the rotor profile parameter optimization method.
Economic Analysis of Methanating CO2 and Hydrogen-Rich Industrial Waste Gas in Depleted Natural Gas Reservoirs
Authors: Hou Zhengmeng , Huang Liangchao , Xie Yachen , Wu Lin , Fang Yanli , Wang Qichen , Guo Yilin
Published: April 2023

This study explored underground biomethanation as a means to achieve carbon neutrality and promote carbon circular utilization by methanating CO2 and hydrogen-rich industrial waste gas in depleted natural gas reservoirs (MECHIG). This approach not only aids the development of carbon capture, utilization, and storage (CCUS) technologies, but also effectively processes industrial waste gas, thereby reducing pollutant emissions. In order to verify the feasibility of the MECHIG concept, this study builds upon the analysis of the MECHIG process overview and employs the net present value (NPV) analysis method to investigate its economic viability. Additionally, the study conducts a sensitivity analysis on six factors, namely methanation efficiency, facility site investment, hydrogen content in waste gas, natural gas prices, operation and maintenance (O&M) investment, and CO2 capture and injection prices. The results indicate the following: (1) Under the baseline scenario, the NPV of the MECHIG concept is approximately CNY 5,035,100, which suggests that the concept may be economically viable. (2) The fluctuation in natural gas prices has the most significant impact on NPV, followed by facility site investment and methanation efficiency. In contrast, the variations in hydrogen content in waste gas, O&M investment, and CO2 capture and injection prices have relatively smaller effects on NPV. (3) To ensure the economic feasibility of the concept, the acceptable fluctuation ranges for the factors of methanation efficiency, facility site investment, hydrogen content in waste gas, natural gas prices, O&M investment, and CO2 capture and injection prices are −16.78%, 5.44%, −32.14%, −4.70%, 14.86%, and 18.56%, respectively.
High-Energy Transformations of Fossil Fuels in the Cement Industry
Authors: Szwed Mirosław , Żukowski Witold , Misztal Krzysztof , Kozłowski Rafał
Published: April 2023

The energy stored in fossil fuels is released through combustion and is a fundamental process in the production of cement. The negative aspect of this combustion is the emission of greenhouse gases and dust. This paper presents the results of a study conducted within a cement plant in Ożarów (south-eastern Poland). The chemical properties (selected elements) in the needles of Scots pine (Pinus sylvestris L.) were determined. The needle surface was scanned using a scanning electron microscope (SEM) and was characterised in terms of chemical composition through energy dispersive spectroscopy (EDS). The concentrations of selected analytes in the biennial needles formed the following descending sequence: Fe > Al > Mn > Zn > Cu > Pb > Cr > Ni. SEM/EDS microphotographs showed the presence of particles of varying shape, size and chemical composition indicative of anthropogenic origin.
Design and Optimization of an Asymmetric Rotor IPM Motor with High Demagnetization Prevention Capability and Robust Torque Performance
Authors: Ding Ling , Cheng Yuan , Zhao Tianxu , Yao Kai , Wang Yao , Cui Shumei
Published: April 2023

In this paper, an asymmetric rotor interior permanent magnet (ARIPM) motor with high demagnetization prevention capability and robust torque performance is proposed. The key contribution of this paper lies in two aspects. On the one hand, a novel asymmetric rotor with a shifted magnet axis is proposed to improve the demagnetization prevention capability and torque density. In order to obtain a proper asymmetric rotor topology of the ARIPM motor, the multi-physical performances, especially the PM demagnetization characteristics of five types of PM arrangements, are analyzed. Furthermore, an asymmetric rotor with V- and VV-type PM arrangement is preliminarily designed, considering the multi-physical performance balance and the potentially high anti-demagnetization ability. On the other hand, it is found that the asymmetric rotor structure can not only improve the nominal value of motor performance but also can enhance the resistance to the influence of manufacturing uncertainties. Therefore, multi-objective optimization of the ARIPM motor with rotor notch design is carried out to obtain an optimal motor structure with both high nominal value and robustness of motor performances. By comparing the simulation results with those of a benchmark motor, the superiority and validity of the proposed ARIPM motor are confirmed. Experimental tests will be carried out in the future to further verify the effectiveness of the proposed motor.
Sustainability Reporting in Energy Companies—Is There a Link between Social Disclosures, the Experience and Market Value?
Authors: Czaja-Cieszyńska Hanna E. , Kordela Dominika
Published: April 2023

As a result of the dissemination of the sustainability concept, social disclosures have become an important area of non-financial reporting, and the energy sector is no exception. The purpose of our article is a multi-faceted evaluation of sustainability reports published by companies operating in the Polish energy sector, from the perspective of social disclosures. The study involved the Polish listed companies that made up the WIG-Energia index. The time scope of the study covers the 2017–2021 period. In total, 54 non-financial reports were analyzed. In the first place, a comparative analysis was carried out to assess the social disclosures made by the WIG-Energia companies against the background of the biggest and the most liquid (blue chip) WIG20 companies. All the applied tools: ESG rating, NFR_S index, and multidimensional data visualization, have confirmed that the energy companies year by year have been presenting larger and larger extents of social disclosures. At the same time, it was observed that the companies appearing for the first time in the WIG-Energia index showed a very small extent of disclosures, whereas the companies which figured in the index throughout the studied period presented a relatively large extent of disclosures, due to their experience in preparing sustainability reports. Next, using the Pearson correlation coefficient (r), we examined the relationship between the energy companies’ market values and the extent of their social disclosures. The results of the statistical analyses have validated the strong and very strong correlation between capitalization and extent of disclosures. It is therefore possible to state that companies with higher market values are characterized by larger extents of social disclosures.
Influences of a Variety of Reinforcements on the Durability of Reinforced Bitumen Sheets Operating at Variable Temperatures
Authors: Francke Barbara , Szymczak-Graczyk Anna , Ksit Barbara , Szulc Jarosław , Sieczkowski Jan
Published: April 2023

This manuscript provides an overview of the most commonly-produced bitumen roofing sheets, focusing on the types of reinforcements used for their production and the reinforcements’ effects on the durability of tensile mechanical properties of roofing sheets under thermal loads. The paper includes the analysis of working conditions of roof coverings in the mid-European transitional climate, i.e., exposed to temperatures passing through 0 °C for three seasons in a year, periodic exposure to negative temperatures reaching −15 °C and positive temperatures up to +70 °C, justifying the above-mentioned emphasis on thermal load. It draws attention to technical problems related to the cooperation of roofing sheets with roofing substrates, with particular emphasis on concrete substrates. For the purposes of the work, the analyses were carried out with regard to the assessment of the service life of roof coverings made of various reinforcements working in conditions of variable temperatures and thus exposed to the transfer of thermal movements of substrate plates. The analyses also included the impact of different coefficients of thermal expansion of the materials in contact with other materials within roof coverings on the incidence of damage to cover layers. Particular attention was paid to the conditions resulting from the production process of roofing sheets effect on the durability of roof coverings made of these materials. Additionally, there were set directions for further work to calculate the impact of stresses, arising in layers of roof coverings during their operation in changeable negative and positive temperatures, on the incidence of mechanical damage to these coverings.
Fate and Impacts of Microplastics in the Environment: Hydrosphere, Pedosphere, and Atmosphere
Authors: Haque Fatima , Fan Chihhao
Published: April 2023

Plastic litter is on the rise where plastic waste ends up in undesignated areas such as the coastal shorelines, where the plastic is exposed to environmental conditions. As a result, the degradation and decomposition of plastics occur, leading to the formation of smaller fragments of plastics, termed microplastics. Microplastics have recently been considered as an emerging class of contaminants due to their ecotoxicological impact on the aquatic environment as well as soil matrix. Microplastics are of a size less than 5 mm and are produced from either a primary source (such as plastic pellets, and beads in makeup products) or a secondary source (such as the wear and tear of normal-use plastics and washing of clothes and textiles). Microplastic pollution is spread across the hydrosphere, pedosphere, and atmosphere, and these environmental zones are being studied for microplastic accumulation individually. However, there exists a source–sink dynamic between these environmental compartments. This study reviews the available literature on microplastic research and discusses the current state of research on the fate and transport of microplastic in the hydrosphere, pedosphere, and atmosphere, explores the ecotoxicological impact of microplastics on aquatic and soil communities, and provides prospective future research directions and plastic waste management strategies to control microplastic pollution. While the fate of microplastics in the hydrosphere is well-documented and researched, studies on understanding the transport mechanism of microplastics in the pedosphere and atmosphere remain poorly understood.
Dynamic Assessment and Change Analysis of Ecosystem Service Value Based on Physical Assessment Method in Cili County, China
Authors: Wang Xinchuang , Liu Xuejie , Wu Yanzhen , Chen Runbo , Wang Shunzhong
Published: April 2023

The effective implementation of ecological protection policies requires the adequate assessment of temporal and spatial changes in the environment. To understand how ecosystem services can be used to track environmental changes, we carried out a study which focused on assessing the changes in the ecosystem services over time and space in Cili County, which is an important forestry region. The method we used was to evaluate the value of the regional ecological services based on the method for evaluating the value equivalent factor per unit area; then, by introducing multi-source data, the InVEST model was optimized to accurately assess the function of the regional ecosystem services, such as carbon storage, soil conservation, and water production. In addition, the values of the ecosystem services and the function assessment results were compared. Finally, based on the results of the optimized InVEST model, the value of the ecosystem services in the study area was regulated and re-evaluated. After re-evaluation, the total value of the ecosystem services in Cili county between 2000 and 2020 still showed an upward trend, increasing from CNY 26.136 billion to CNY 35.444 billion, with a total increase of CNY 9.308 billion. Compared to before the re-evaluation, the total value of the ecosystem services only increased from CNY 32.243 billion to CNY 32.473 billion, with a total increase of CNY 0.23 billion; the change in the value of the ecosystem services was more obvious, with a stronger spatial heterogeneity. The areas with high ecosystem service value in Cili County are mainly concentrated in the eastern parts, as well as the northwestern and southern parts, while the areas with low value are mainly concentrated in the central part of Cili County. The value of the central, southern, and northwestern parts of Cili County increased significantly. Such changes are closely related to China’s implementation of ecological protection policies in this region since 2000, such as returning farmland to forest and natural forest protection. The evaluation results of the ecosystem services and the method for evaluating the value equivalent factor in this study are more consistent with the changes in the ecosystem services in the study area. The dynamic assessment method of ecosystem service value proposed in this study is helpful in achieving accurate assessments of the regional ecosystem services and thus provides a useful reference for the formulation of more reasonable regional ecological protection policies.
Achievements of Autochthonous Wine Yeast Isolation and Selection in Romania—A Review
Authors: Rădoi-Encea Raluca-Ștefania , Pădureanu Vasile , Diguță Camelia Filofteia , Ion Marian , Brîndușe Elena , Matei Florentina
Published: April 2023

Winemaking in Romania has a long-lasting history and traditions and its viticulture dates back centuries. The present work is focused on the development of wine yeast isolation and selection performed in different Romanian winemaking regions during past decades, presenting the advanement of the methods and techniques employed, correlated with the impact on wine quality improvement. Apart from the historical side of such work, the findings will reveal how scientific advancement in the country was correlated with worldwide research in the topic and influenced local wines’ typicity. To create an overall picture of the local specificities, the work refers to local grape varieties and the characteristics of the obtained wines by the use of local yeasts as compared to commercial ones. Numerous autochthonous strains of Saccharomyces were isolated from Romanian vineyards, of which several demonstrated strong oenological characteristics. Meanwhile, different non-Saccharomyces yeast strains were also isolated and are nowadays receiving the attention of researchers seeking to develop new wines according to wine market tendencies and to support wine’s national identity.
Protecting Function Privacy and Input Privacy in the Publicly Verifiable Outsourcing Computation of Polynomial Functions
Authors: Song Beibei , Zhou Dehua , Wu Jiahe , Yuan Xiaowei , Zhu Yiming , Wang Chuansheng
Published: April 2023

With the prevalence of cloud computing, the outsourcing of computation has gained significant attention. Clients with limited computing power often outsource complex computing tasks to the cloud to save on computing resources and costs. In outsourcing the computation of functions, a function owner delegates a cloud server to perform the function’s computation on the input received from the user. There are three primary security concerns associated with this process: protecting function privacy for the function owner, protecting input privacy for the user and guaranteeing that the cloud server performs the computation correctly. Existing works have only addressed privately verifiable outsourcing computation with privacy or publicly verifiable outsourcing computation without input privacy or function privacy. By using the technologies of homomorphic encryption, proxy re-encryption and verifiable computation, we propose the first publicly verifiable outsourcing computation scheme that achieves both input privacy and function privacy for matrix functions, which can be extended to arbitrary multivariate polynomial functions. We additionally provide a faster privately verifiable method. Moreover, the function owner retains control over the function.
A Reverse Shortest Path Tree-Based Multicast Joining Node Selection Method
Authors: Tian Zhenyu , You Jiali , Hu Linlin
Published: April 2023

Network layer multicast is a powerful method for transmitting data from sources to multiple group members. When joining a multicast group, a group member first sends a request to a designated router (DR). Then, the DR selects a node in the existing multicast tree (known as a multicast joining node, or MJN) to establish a multicast distribution path from the MJN to itself. The MJN selection method runs on the DR and has a significant impact on the distribution of the multicast tree, that directly affects the load distribution in the network. However, the current MJN selection method cannot effectively detect the load status of the downlink multicast path in the case of asymmetric routing, leading to network congestion and limiting the number of multicast groups that the network can accommodate (multicast capacity). To solve this problem, we propose an MJN selection method based on the reverse shortest path tree (RSPT). RSPT can effectively detect the load status of downlink multicast paths in case of routing asymmetry. Based on the detection results of RSPT, DR can select the MJN with the lowest path load to join the multicast tree. Our experimental results indicate that compared to existing multicast methods, our method has a lower cost and delay, and can effectively balance the network load in the case of asymmetric routing, increasing multicast capacity by more than two times.
Reproduction of Hatchery-Reared Pike-Perch (Sander lucioperca) Fed Diet with Low-Marine-Ingredients: Role of Dietary Fatty Acids
Authors: Péter Géza , Lukić Jovanka , Milla Sylvain , Sándor Zsuzsanna J. , Brlás-Molnár Zsuzsanna , Ardó László , Bekefi Emese , Ljubobratović Uroš
Published: April 2023

This research aimed to evaluate the reproductive potential of hatchery-reared (F1) pike-perch (Sander lucioperca) broodstock fed a commercial diet with low levels of long-chain polyunsaturated fatty acids (Lc-PUFA) and wild (F0) pike-perch broodstock fed forage fish. Reproductive parameters, including pseudogonadosomatic index (PGSI), egg size, latency time, hatching rate, embryo survival, and eggs’ fatty acid (FA) composition, as well as plasma sex hormone, glucose and immunoglobulin levels after hormone injection, were analyzed. The results showed low PGSI (10% in F1 vs. 14% in F0) and embryo survival (24% in F1 vs. 61% in F0) in F1 broodstock, but a satisfactory hatching rate (63% in F1 vs. 78% in F0) and larval size (4.6 mm in F1 vs. 4.7 mm in F0). A low arachidonic acid (ARA) percentage in F1 fish eggs (1.32%), along with increased immunoglobulin levels (17.31 g/L), suggests that immune system activation might have depleted the reserves of ARA in F1 fish, which is the key fatty acid for successful oocyte maturation. We assumed that the administration of more sustainable diets, based on terrestrial plant ingredients, is not inferior to higher-quality diets based on marine ingredients.
Smoothed Particle Hydrodynamics-Based Study of 3D Confined Microflows
Authors: Chatzoglou Efstathios , Liakopoulos Antonios , Sofos Filippos
Published: April 2023

In this study, we investigate the performance of the smoothed particle hydrodynamics (SPH) method regarding the computation of confined flows in microchannels. Modeling and numerical simulation with SPH involve the representation of flowing matter as distinct mass points, leading to particle discretization of the Navier–Stokes equations. The computational methodology exhibits similarities with other well-established particle methods, such as molecular dynamics (MD), dissipative particle dynamics (DPD), and smooth dissipative particle dynamics (SDPD). SPH has been extensively tested in the simulation of free-surface flows. However, studies on the performance of the method in internal flow computations are limited. In this work, we study flows in microchannels of variable cross-sections with a weakly compressible SPH formulation. After preliminary studies of flows in straight constant cross-section ducts, we focus on channels with sudden expansion and/or contraction. Flow models based on periodic or various inlet/outlet boundary conditions and their implementations are discussed in the context of 2D and 3D simulations. Numerical experiments are conducted to evaluate the accuracy of the method in terms of flowrate, velocity profiles, and wall shear stress. The relation between f and Re for constant cross-section channels is computed with excellent accuracy. SPH captured the flow characteristics and achieved very good accuracy. Compressibility effects due to the weakly compressible smoothed particle hydrodynamics (WCSPH) formulation are negligible for the flows considered. Several typical difficulties and pitfalls in the application of the SPH method in closed conduits are highlighted as well as some of the immediate needs for the method’s improvement.
Comparison of the Chemical Composition of Six Canihua (Chenopodium pallidicaule) Cultivars Associated with Growth Habits and after Dehulling
Authors: Mérida-López Jenny , Pérez Sander Jonathan , Morales Rocío , Purhagen Jeanette , Bergenståhl Björn , Rojas Cinthia Carola
Published: April 2023

The canihua (Chenopodium pallidicaule) is a native Andean crop that stands out for its high content of protein, fiber, and minerals and that has a good fatty acid profile. We studied six canihuas cultivars, which were compared according to their proximate, mineral, and fatty acid composition. Based on the form of stems, termed growth habit, they belonged to two groups: decumbent (Lasta Rosada, Illimani, Kullaca, and Cañawiri) and ascending (Saigua L24 and Saigua L25). Dehulling is an important process applied to this grain. However, there is no information about how it affects the chemical composition of the canihua. Dehulling resulted in two levels, whole and dehulled canihua. The highest protein and ash contents were in whole Saigua L25 (19.6 and 5.12 g/100 g, respectively), and the highest fat content was found in dehulled Saigua L25, while the whole grains of Saigua L24 presented the highest fiber content (12.5 g/100 g). Dehulling mainly affected the macro-minerals content, while micro-minerals were only slightly linked to the dehulling. The growth habit influenced the C18:1 and C18:3 contents. In conclusion, the canihua had a nutritional composition influenced by each variety, strongly influenced by dehulling, and to a lesser extent by growth habit.
Microbial Diversity and Correlation between Breast Milk and the Infant Gut
Authors: Wang Kaili , Xia Xiufang , Sun Lina , Wang Hui , Li Qiu , Yang Zhuo , Ren Jing
Published: April 2023

The gut microbiota is significant for infants to grow and develop in the early stages of life. The breast milk microbiota directly or indirectly influences colonizing and the development of early infant intestinal microbiota. Therefore, we wanted to study the microbial diversity and correlation between breast milk and the infant gut. By sequencing the 16S rRNA V3–V4 regions of microbiome in infant feces 1, 14, 20, 30, and 90 days after delivery as well as those in breast milk using Illumina NovaSeq, we studied the component of microbiome in both human milk and infant stools, analyzed the diversity of microbiota, and explored the relationship between them. We found that the richest bacteria in breast milk were Acinetobacter, Stenotrophomonas, Sphingopyxis, Pseudomonas, and Streptococcus, with a small amount of Lactobacillus, Bifidobacterium, and Klebsiella. The infant feces were abundant in Bifidobacterium, Escherichia-Shigella, Klebsiella, Streptococcus, Serratia, Bacteroides, and Lactobacillus, with a small number of Acinetobacter and Pseudomonas. Acinetobacter, Bifidobacterium, Klebsiella, and Lactobacillus appeared in the breast milk and infant feces, suggesting that they were transferred from the breast milk to the infant’s gut.
Physical Blending of Fractionated Bambangan Kernel Fat Stearin and Palm Oil Mid-Fraction to Formulate Cocoa Butter Equivalent
Authors: Mohammad Ridwan Norazlina , Mamat Hasmadi , Haque Akanda Md Jahurul
Published: April 2023

In this study, the physicochemical properties, composition, thermal properties, and crystal microstructure of fractionated bambangan kernel fat stearin and palm oil mid-fraction blends were investigated with respect to a potential cocoa butter equivalent. The blends were prepared in five ratios, and all of the blends exhibited similar physicochemical properties to cocoa butter. Although all of the blends had similar physicochemical properties, the blend containing 70% bambangan kernel fat stearin and 30% palm oil mid-fraction showed remarkable similarity to cocoa butter. The blend had similar fatty acid and triacylglycerol content to cocoa butter with 18.74% palmitic acids, 38.26% stearic acids, 34.05% oleic acids, 15.20% 1,3-dipalmitoyl-2-oleoyl glycerol, and 29.74% 1,3-disteroyl-2-oleoyl glycerol with improved thermostability (high solid fat content at 30 °C but reaching 0% at 40 °C). It also exhibited spherulite crystals with a needle-like crystal structure of 50 µm. This mixture showed good compatibility with cocoa butter at all mixing ratios; hence, it is suggested as a potential cocoa butter equivalent.
Geographical Classification of Saffron (Crocus Sativus L.) Using Total and Synchronous Fluorescence Combined with Chemometric Approaches
Authors: El Hani Ouarda , García-Guzmán Juan , Palacios-Santander José , Digua Khalid , Amine Aziz , Gharby Said , Cubillana-Aguilera Laura
Published: April 2023

There is an increasing interest in food science for high-quality natural products with a distinct geographical origin, such as saffron. In this work, the excitation-emission matrix (EEM) and synchronous fluorescence were used for the first time to geographically discriminate between Moroccan saffron from Taroudant, Ouarzazate, and Azilal. Moreover, to differentiate between Afghan, Iranian, and Moroccan saffron, a unique fingerprint was assigned to each sample by visualizing the EEM physiognomy. Moreover, principal component analysis (LDA) and linear discriminant analysis (LDA) were successfully applied to classify the synchronous spectra of samples. High fluorescence intensities were registered for Ouarzazate and Taroudant saffron. Yet, the Azilal saffron was distinguished by its low intensities. Furthermore, Moroccan, Afghan, and Iranian saffron were correctly assigned to their origins using PCA and LDA for different offsets (Δλ) (20–250 nm) such that the difference in the fluorescence composition of the three countries’ saffron was registered in the following excitation/emission ranges: 250–325 nm/300–480 nm and 360–425 nm/500–550 nm. These regions are characterized by the high polyphenolic content of Moroccan saffron and the important composition of Afghan saffron, including vitamins and terpenoids. However, weak intensities of these compounds were found in Iranian saffron. Furthermore, a substantial explained variance (97–100% for PC1 and PC2) and an important classification rate (70–90%) were achieved. Thus, the non-destructive applied methodology of discrimination was rapid, straightforward, reliable, and accurate.
Multi-Criteria Optimization including Environmental Impacts of a Microwave-Assisted Extraction of Polyphenols and Comparison with an Ultrasound-Assisted Extraction Process
Authors: Bouchez Alice , Vauchel Peggy , Périno Sandrine , Dimitrov Krasimir
Published: April 2023

Valorization of wastes and by-products using environmentally friendly technologies with an optimal cost–benefit relationship is a current major issue in agri-food industries. An original tool was recently developed for multi-criteria optimization of an ultrasound-assisted extraction (UAE) process including the assessment of environmental impacts using Life Cycle Assessment. In the present work, this methodology was adapted and applied to another green extraction process, microwave-assisted extraction (MAE), with the same case study, valorization of antioxidant polyphenols from downgraded beet seeds. Once built, the obtained multi-criteria optimization tool was used to investigate performances of the MAE process regarding productivity criteria (polyphenol concentration and antioxidant activity of the extracts), energy consumption and environmental impacts as functions of operating parameters (time, solvent composition, microwave power density, and liquid–solid ratio). The MAE process was optimized under different constraints and compared to the UAE process. For the studied conditions and different investigated scenarios, MAE enabled obtaining extracts with higher polyphenol concentrations and antioxidant activity (approximately 33% and 23% enhancements, respectively), and to strongly reduce extraction duration (by a factor up to 6), whereas UAE enabled reducing the energy consumption (up to 3.6 fold) and the environmental impacts (up to 12% for climate change).