bluuebunny/crossref_metadata_2025 huggingface dataset:
A Transient Productivity Prediction Model for Horizontal Wells Coupled with Oil and Gas Two-Phase Seepage and Wellbore Flow
Authors: Ke Wenqi , Luo Wei , Miao Shiyu , Chen Wen , Hou Yaodong
Published: July 2023

Capacity prediction is the basis for the optimization of oil and gas well production work systems and parameter optimization design. Horizontal wells are becoming increasingly popular for oil and gas extraction. However, the seepage law of reservoirs produced with horizontal wells is more complicated than that of reservoirs produced with vertical wells, especially when the bottom hole flowing pressure or formation pressure is less than the saturation pressure of crude oil in the reservoir. Oil and gas two-phase seepage can occur in a part or all areas of the wellbore and reservoir. Because the oil and gas two-phase seepage characteristics of reservoir oil well production will be reduced—possibly greatly reduced—the formation seepage law is complex. Thus, it is very important to better predict the horizontal well capacity. To address this, a method and process of establishing a transient calculation model of two-phase flow in horizontal wells are introduced in detail from three aspects: fluid physical properties, reservoir oil and gas two-phase seepage, and the coupling model of the inflow performance and flow in the wellbore. The model is found to be reliable through verification with production data from five wells in two oilfields. The established model simplifies the reservoir model, does not involve very complex meshing, and only simulates one well. Therefore, the calculation speed will be faster than that of other reservoir numerical simulation methods under the same conditions.
Effect of Al2O3, SiO2, and ZnO Nanoparticle Concentrations Mixed with EG–Water on the Heat Transfer Characteristics through a Microchannel
Authors: Elbadawy Ibrahim , Alali Fatemah , Derakhshandeh Javad Farrokhi , Dinc Ali , Abouelela Mohamed , Al-Kouz Wael
Published: July 2023

Nanofluids have gained attention for their potential to solve overheating problems in various industries. They are a mixture of a base fluid and nanoparticles dispersed on the nanoscale. The nanoparticles can be metallic, ceramic, or carbon based, depending on the desired properties. While nanofluids offer advantages, challenges such as nanoparticle agglomeration, stability, and cost effectiveness remain. Nonetheless, ongoing research aims to fully harness the potential of nanofluids in addressing overheating issues and improving thermal management in different applications. The current study is concerned with the fluid flow and heat transfer characteristics of different nanofluids using different types of nanoparticles such as Al2O3, SiO2, and ZnO mixed with different base fluids. Pure water and ethylene glycol–water (EG–H2O) mixtures at different EG–H2O ratios (ψ = 0%, 10%, 30%, 40%) are used as the base fluid. Furthermore, a rectangular microchannel heat sink is used. Mesh independent study and validation are performed to investigate the current model, and a good agreement is achieved. The numerical analysis evaluates the influence on the heat transfer coefficient and flow characteristics of nanofluids for Reynolds numbers 500 to 1200 at a 288 K inlet flow temperature. The results show that ZnO nanofluid and 40% EG–H2O increase the heat transfer coefficient by 63% compared to ZnO–H2O nanofluid obtained at Re = 1200 and φ = 5%. Conversely, the pressure drop by ZnO is nearly double that obtained by Al2O3 and SiO2.
Forecasting Regional Ionospheric TEC Maps over China Using BiConvGRU Deep Learning
Authors: Tang Jun , Zhong Zhengyu , Hu Jiacheng , Wu Xuequn
Published: July 2023

In this paper, we forecasted the ionospheric total electron content (TEC) over the region of China using the bidirectional convolutional gated recurrent unit (BiConvGRU) model. We first generated the China Regional Ionospheric Maps (CRIMs) using GNSS observations provide by the Crustal Movement Observation Network of China (CMONOC). We then used gridded TEC maps from 2015 to 2018 with a 1 h interval from the CRIMs as the dataset, including quiet periods and storm periods of ionospheric TEC. The BiConvGRU model was then utilized to forecast the ionospheric TEC across China for the year 2018. The forecasted TEC was compared with the TEC from the International Reference Ionosphere (IRI-2016), Convolutional Long Short-Term Memory (ConvLSTM), Convolutional Gated Recurrent Unit (ConvGRU), Bidirectional Convolutional Long Short-Term Memory (BiConvLSTM), and the 1-day Predicted Global Ionospheric Map (C1PG) provided by the Center for Orbit Determination in Europe (CODE). In addition, indices including Kp, ap, Dst and F10.7 were added to the training dataset to improve the forecasting accuracy of the model (-A indicates no indices, while -B indicates with indices). The results verified that the prediction accuracies of the models integrated with these indices were significantly improved, especially during geomagnetic storms. The BiConvGRU-B model presented a decrease of 41.5%, 22.3%, and 13.2% in the root mean square error (RMSE) compared to the IRI-2016, ConvGRU, and BiConvLSTM-B models during geomagnetic storm days. Furthermore, at a specific grid point, the BiConvGRU-B model showed a decrease of 42.6%, 49.1%, and 31.9% in RMSE during geomagnetic quiet days and 30.6%, 34.1%, and 15.1% during geomagnetic storm days compared to the IRI-2016, C1PG, and BiConvLSTM-B models, respectively. In the cumulative percentage analysis, the BiConvGRU-B model had a significantly higher percentage of mean absolute error (MAE) within the range of 0–1 TECU in all seasons compared to the BiConvLSTM-B model. Meanwhile, the BiConvGRU-B model outperformed the BiConvLSTM-B model with lower RMSE for each month of 2018.
Hybrid Deep Learning and S2S Model for Improved Sub-Seasonal Surface and Root-Zone Soil Moisture Forecasting
Authors: Xu Lei , Yu Hongchu , Chen Zeqiang , Du Wenying , Chen Nengcheng , Huang Min
Published: July 2023

Surface soil moisture (SSM) and root-zone soil moisture (RZSM) are key hydrological variables for the agricultural water cycle and vegetation growth. Accurate SSM and RZSM forecasting at sub-seasonal scales would be valuable for agricultural water management and preparations. Currently, weather model-based soil moisture predictions are subject to large uncertainties due to inaccurate initial conditions and empirical parameterization schemes, while the data-driven machine learning methods have limitations in modeling long-term temporal dependences of SSM and RZSM because of the lack of considerations in the soil water process. Thus, here, we innovatively integrate the model-based soil moisture predictions from a sub-seasonal-to-seasonal (S2S) model into a data-driven stacked deep learning model to construct a hybrid SSM and RZSM forecasting framework. The hybrid forecasting model is evaluated over the Yangtze River Basin and parts of Europe from 1- to 46-day lead times and is compared with four baseline methods, including the support vector regression (SVR), random forest (RF), convolutional long short-term memory (ConvLSTM) and the S2S model. The results indicate substantial skill improvements in the hybrid model relative to baseline models over the two study areas spatiotemporally, in terms of the correlation coefficient, unbiased root mean square error (ubRMSE) and RMSE. The hybrid forecasting model benefits from the long-lead predictive skill from S2S and retains the advantages of data-driven soil moisture memory modeling at short-lead scales, which account for the superiority of hybrid forecasting. Overall, the developed hybrid model is promising for improved sub-seasonal SSM and RZSM forecasting over global and local areas.
Automatic Extraction of Saltpans on an Amendatory Saltpan Index and Local Spatial Parallel Similarity in Landsat-8 Imagery
Authors: Jiao Xiangyu , Shi Xiaofei , Shen Ziyang , Ni Kuiyuan , Deng Zhiyu
Published: July 2023

Saltpans extraction is vital for coastal resource utilization and production management. However, it is challenging to extract saltpans, even by visual inspection, because of their spatial and spectral similarities with aquaculture ponds. Saltpans are composed of crystallization and evaporation ponds. From the whole images, existing saltpans extraction algorithms could only extract part of the saltpans, i.e., crystallization ponds. Meanwhile, evaporation ponds could not be efficiently extracted by only spectral analysis, causing the degeneration of saltpans extraction. In addition, manual intervention was required. Thus, it is essential to study the automatic saltpans extraction algorithm of the whole image. As to the abovementioned problems, this paper proposed a novel method with an amendatory saltpan index (ASI) and local spatial parallel similarity (ASI-LSPS) for extracting coastal saltpans. To highlight saltpans and aquaculture ponds in coastal water, the Hessian matrix has been exploited. Then, a new amendatory saltpans index (ASI) is proposed to extract crystallization ponds to reduce the negative influence of turbid water and dams. Finally, a new local parallel similarity criterion is proposed to extract evaporation ponds. The Landsat-8 OLI images of Tianjin and Dongying, China, have been used in experiments. Experiments have shown that ASI can reach at least 70% in intersection over union (IOU) and 78% in Kappa for extraction of crystallization in saltpans. Moreover, experiments also demonstrate that ASI-LSPS can reach at least 82% in IOU and 89% in Kappa on saltpans extraction, at least 13% and 17% better than comparing algorithms in IOU and Kappa, respectively. Furthermore, the ASI-LSPS algorithm has the advantage of automaticity in the whole imagery. Thus, this study can provide help in coastal saltpans management and scientific utilization of coastal resources.
The Use of Neural Network Modeling Methods to Determine Regional Threshold Values of Hydrochemical Indicators in the Environmental Monitoring System of Waterbodies
Authors: Tunakova Yulia , Novikova Svetlana , Valiev Vsevolod , Baibakova Evgenia , Novikova Ksenia
Published: July 2023

The regulation of the anthropogenic load on waterbodies is carried out based on water quality standards that are determined using the threshold values of hydrochemical indicators. These applied standards should be defined both geographically and differentially, taking into account the regional specifics of the formation of surface water compositions. However, there is currently no unified approach to defining these regional standards. It is, therefore. appropriate to develop regional water quality standards utilizing modern technologies for the mathematical purpose of methods analysis using both experimental data sources and information system technologies. As suggested by the use of sets of chemical analysis and neural network cluster analysis, both methods of analysis and an expert assessment could identify surface water types as well as define the official regional threshold values of hydrochemical system indicators, to improve the adequacy of assessments and ensure the mathematical justification of developed standards. The process for testing the proposed approach was carried out, using the surface water resource objects in the territory of the Republic of Tatarstan as our example, in addition to using the results of long-term systematic measurements of informative hydrochemical indicators. In the first stage, typing was performed on surface waters using the neural network clustering method. Clustering was performed based on sets of determined hydrochemical parameters in Kohonen’s self-organizing neural network. To assess the uniformity of data, groups in each of the selected clusters were represented by specialists in this subject area’s region. To determine the regional threshold values of hydrochemical indicators, statistical data for the corresponding clusters were calculated, and the ranges of these values were used. The results of testing this proposed approach allowed us to recommend it for identifying surface water types, as well as to define the threshold values of hydrochemical indicators in the territory of any region with different surface water compositions.
Human Olfactory Receptor Sensor for Odor Reconstitution
Authors: Kuroda Shun’ichi , Nakaya-Kishi Yukiko , Tatematsu Kenji , Hinuma Shuji
Published: July 2023

Among the five human senses, light, sound, and force perceived by the eye, ear, and skin, respectively are physical phenomena, and therefore can be easily measured and expressed as objective, univocal, and simple digital data with physical quantity. However, as taste and odor molecules perceived by the tongue and nose are chemical phenomena, it has been difficult to express them as objective and univocal digital data, since no reference chemicals can be defined. Therefore, while the recording, saving, transmitting to remote locations, and replaying of human visual, auditory, and tactile information as digital data in digital devices have been realized (this series of data flow is defined as DX (digital transformation) in this review), the DX of human taste and odor information is not yet in the realization stage. Particularly, since there are at least 400,000 types of odor molecules and an infinite number of complex odors that are mixtures of these molecules, it has been considered extremely difficult to realize “human olfactory DX” by converting all odors perceived by human olfaction into digital data. In this review, we discuss the current status and future prospects of the development of “human olfactory DX”, which we believe can be realized by utilizing odor sensors that employ the olfactory receptors (ORs) that support human olfaction as sensing molecules (i.e., human OR sensor).
Combatting Fake News: A Global Priority Post COVID-19
Authors: Calvo-Gutiérrez Elvira , Marín-Lladó Carles
Published: July 2023

This paper reviews some academic works on fake news published in Spain in the last seven years, a period in which the 2016 and 2020 US elections and the COVID-19 pandemic marked a turning point in the ’era of disinformation’, a term that the European Union (EU) describes as “verifiably false or misleading information that is created, presented and disseminated for profit or to deliberately mislead the public, and is likely to cause public harm”. Methodology: Some of the most relevant academic articles on fake news published from 2016 to the present were analysed. Results: In the last seven years, hoaxes and fake news have become even more sophisticated—including audiovisual materials, known as deep fakes—and constitute a political and social concern of the first order insofar as they threaten democratic life and social harmony in all countries. Conclusions: Although it is not a phenomenon specific to the media, since it has found its natural medium in social networks and the Internet, disinformation—which polarises society and fosters hatred—once again calls into question the role of journalism in the world.
How Employee Job Burnout, Work Engagement, and Turnover Intention Relate to Career Plateau during the Epidemic
Authors: Bai Yang , Zhou Jinquan , He Wenjin
Published: July 2023

In light of the impact of the COVID-19 epidemic on organizations and company human resource policies, multiple changes have been made to employee work behaviors. This paper developed a concept model on career plateaus, job burnout, work engagement, and turnover intention and examined it through a non-random sampling survey of 285 employees at resorts in Macao. The results revealed that career plateaus positively impact job burnout and turnover intention, and job burnout positively impacts turnover intention. The study found that career plateau negatively impacts work engagement and positively impacts turnover intention, and work engagement negatively influences turnover intention. Job burnout and work engagement partially mediate the relationship between career plateau and turnover intention. Training negatively moderates career plateau toward work engagement, and job rotation moderates career plateau toward turnover intention. Accordingly, organizations should consider the impact on employees’ careers when designing training and job rotation policies in response to the epidemic.
Mixed Design Optimization of Polymer-Modified Asphalt Mixtures (PMAs) Containing Carton Plastic Packaging Wastes
Authors: Monticelli Riccardo , Roberto Antonio , Romeo Elena , Tebaldi Gabriele
Published: July 2023

This study investigated the potential of reusing plastics derived from multilayered food carton recycling processes as a modifier for asphalt mixtures by dry process. Two types of plastics, one untreated and one pelletized, were added to a mixture containing neat asphalt binder using three different dry methods and in two different amounts (2 and 5% by weight of aggregates). The chemical and physical properties of the plastics were explored via differential scanning calorimetry (DSC) and laser diffraction granulometry. The fracture behavior of the polymer-modified asphalt (PMA) mixtures was evaluated via superpave indirect tensile (IDT) testing at 10 °C and comparative analysis with the reference and a mixture composed of the same aggregate curve and a traditional styrene–butadiene–styrene (SBS)-modified asphalt binder. The role of the plastic during crack initiation and propagation was investigated via microscopic analysis. The results show that plastics derived from carton recycling processes can be successfully used as an additive in asphalt mixtures via the dry method due to the compatibility between their melting and mixing temperatures. The shape of the plastics influences the cracking propagation and resistance of the mixture. Finally, the presence of plastics in the mixture reduces the proneness to accumulate deformation (about 50% less than the reference ones) and increases the failure resistance, leading to a better cracking response at intermediate temperatures.
How Does Industrial Upgrading Affect Carbon Productivity in China’s Service Industry?
Authors: Weng Shimei , Chen Jianbao
Published: July 2023

Promoting carbon productivity is an effective way to reduce carbon emissions. The existing literature focuses mainly on the carbon productivity of heavily polluted sectors, such as heavy industry, the manufacturing industry, and the construction industry. With the deepening of China’s economic transformation and industrial upgrading, the service industry plays an increasingly important role in the national economy, and the ratio and amount of carbon emissions in the service industry show an upward trend. In order to effectively achieve the goal of energy conservation and emission reduction, it is necessary to study how industrial upgrading affects the carbon productivity in the service industry. This study uses a spatial autoregressive panel model to investigate the carbon productivity in China’s service industry. The empirical results are summarized as follows: (1) the carbon productivity of China’s service industry is on the rise, and there exist regional heterogeneity and spatial dependence; (2) industrial upgrading has a significant positive effect on the carbon productivity in China’s service industry; (3) the positive effect of industrial upgrading in the eastern (northern) region is higher than that in middle and western (southern) regions in the service industry; and (4) environmental regulation and economic development have positive moderating effects in the process of industrial upgrading. Accordingly, some targeted policy suggestions are put forward.
Relationships between Outdoor Recreation-Associated Flow, Pro-Environmental Attitude, and Pro-Environmental Behavioral Intention
Authors: Han Gun-Soo
Published: July 2023

This study was performed to identify relationships between flow associated with outdoor recreation, pro-environmental attitude, and pro-environmental behavioral intention. One hundred and thirty-one students from outdoor recreation clubs at 20 universities participated in the study. Structural equation modeling by using AMOS 20.0 revealed the following. First, outdoor recreation-associated flow has a direct positive effect on pro-environmental attitudes. Second, the pro-environmental attitude has a direct positive effect on pro-environmental behavioral intention. Third, outdoor recreation-associated flow does not have a direct positive effect on pro-environmental behavioral intention. Fourth, outdoor recreation-associated flow indirectly influences pro-environmental behavioral intention mediated by environmental attitude.
Social Inequality in Popular Neighborhoods: A Pre- and Post-Pandemic Perspective from Joint Accessibility
Authors: Gallego Méndez Jorge , García-Moreno Lina M. , Murillo-Hoyos Jackeline , Jaramillo Molina Ciro
Published: July 2023

The existence of barriers to accessing essential urban opportunities leads to differentiated use of the territory, which can generate social fragmentation. Several authors highlight the role of public transportation services for reducing inequality gaps by providing connections between origins and destinations. The COVID-19 health emergency in 2020 highlighted the complex situation faced by disadvantaged populations in coping with crises in the absence of transportation services. Considering four popular neighborhoods in Santiago de Cali, Colombia, as a case study, patterns of public transport provision, the potential for access to opportunities, and joint accessibility patterns for 2015 and 2021 were evaluated through methods based on spatial analysis. A decrease in public transport provision of approximately 25% and an increase in travel times close to 23 min were detected by 2021. The results show deficits in the provision of transportation services and low accessibility in the study area and reinforce the hypothesis raised about the existence of housing segregation and spatial inequality located on the city’s urban edge, which are marked in both scenarios.
The Single-Channel Microseismic Mine Signal Denoising Method and Application Based on Frequency Domain Singular Value Decomposition (FSVD)
Authors: Zhu Quanjie , Sui Longkun , Li Qingsong , Li Yage , Gu Lei , Wang Dacang
Published: July 2023

The purpose of denoising microseismic mine signals (MMS) is to extract relevant signals from background interference, enabling their utilization in wave classification, identification, time analysis, location calculations, and detailed mining feature analysis, among other applications. To enhance the signal-to-noise ratio (SNR) of single-channel MMS, a frequency-domain denoising method based on the Fourier transform, inverse transform, and singular value decomposition was proposed, along with its processing workflow. The establishment of key parameters, such as time delay, τ, reconstruction order, k, Hankel matrix length, n, and dimension, m, were introduced. The reconstruction order for SVD was determined by introducing the energy difference spectrum, E, and the denoised two-dimensional microseismic time series was obtained based on the SVD recovery principle. Through the analysis and processing of three types of typical microseismic waveforms in mining (blast, rock burst, and background noise) and with the evaluation of four indicators, SNR, ESN, RMSE, and STI, the results show that the SNR is improved by more than 10 dB after FSVD processing, indicating a strong noise suppression capability. This method is of significant importance for the rapid analysis and processing of microseismic signals in mining, as well as subsequently and accurately picking the initial arrival times and the exploration and analysis of microseismic signal characteristics in mines.
Remote Cultural Events: Investigating the Usefulness of Live Streaming for Creating Cultural and Social Engagement in Communities of Older Adults
Authors: Caiola Valentina , Moreira Kares Elina , Pillan Margherita , Spallazzo Davide , Tuomi Aarni
Published: July 2023

The rise of the silver economy has drawn a growing interest in understanding the needs and behaviours of older adults, both by academics as well as the business and public sectors. Services promoting wellbeing can have several benefits both on individual and national levels, and social connectedness, as one aspect of wellbeing, has been found to positively impact healthy ageing and quality of life among older adults. The aim of this study was to conduct a first exam of the potentials of a remote cultural event to facilitate social connectedness and well-being in a community of older adults through culture and the arts. This study utilised a qualitative exploratory approach in the form of a co-designed case study set in a Finnish care home. An opera streaming event was planned and organised in co-operation with multiple stakeholders including the residents. The results highlight the role of social interaction as part of a remote cultural experience, prior, during, and post-experience. Partaking in the event resulted in enhanced social connectedness, more positive views on technology and remote experiences, and overall satisfaction for joining. The social aspect, rituals, and etiquette are also present also in watching opera remotely, and emphasising these aspects in designing such services could leverage the potential that digital cultural experiences hold.
Biogeochemical Characteristics of Sedimentary Organic Matter in Coastal Waters of a Mariculture Area: The Big Impact of Bay Scallop Farming
Authors: Yang Bo , Gao Xuelu , Liu Jin , Xie Lei , Zhao Jianmin , Xing Qianguo , Donnici Sandra , Tosi Luigi , Tang Cheng
Published: July 2023

Four short sediment cores were collected to explore the impacts of bay scallop farming on the composition and accumulation of sedimentary organic matter (SOM). The results revealed that SOM was mainly composed of relatively easily biodegradable substances as evidenced by the high contribution rate of biopolymeric carbon (77.8–94.4%). The sediment accumulation rate in the scallop farming area (SFA) was 28.6% higher than that in the non-scallop farming area (NSFA). The total organic carbon (TOC) and total nitrogen (TN) burial fluxes in the SFA were 33.1 and 36.6% higher than those in the NSFA, respectively. A rough estimate showed that the burial fluxes of TOC, TN, scallop-derived OC, and marine algal-derived OC in the ~150 km2 SFA could increase by 1.08, 0.11, 0.39, and 0.68 g m−2 yr−1, respectively, with annual scallop production increasing 104 t. This study highlights the significant effects of scallop farming on the biogeochemistry of SOM in coastal waters, which provides a direct reference for future research on the carbon cycle in shellfish culture areas.
Response of Soil Aggregate Stability to Phosphorus, Nitrogen, and Organic Fertilizer Addition: A Meta-Analysis
Authors: Liu Xiaolan , Liu Jigen , Huang Jinquan , Chen Yanfei , Zhang Lu , Qi Yujie , Li Weiwen , Zhu Yi
Published: July 2023

Soil is a highly significant resource for human survival, and agglomerates, as the basic unit of the soil structure, not only enhance the soil fertility and control the biological validity of nutrients but also strengthen the soil’s erosion resistance. The mass application of fertilizers may significantly affect crop growth and the soil structure, and the rational application and dispensing of fertilizers will be an urgent issue to be addressed. Therefore, the effect of fertilizer application on the stability of water-stable soil aggregates needs to be studied under different meteorological and soil conditions to draw more general and feasible conclusions. Our meta-analysis of data from 220 independent observations from 56 published studies found that fertilizer application increased the mean weight diameter (MWD) by an average of 18% compared to the no-fertilizer treatment. Among the nitrogen (N), phosphate (P), and organic (OM) fertilizer treatments, the organic fertilizer treatment had a more significant stimulatory effect on the MWD (26%). Among the different fertilizer levels, a low level of phosphorus (<40 kg·ha−1 yr−1), a high level of N (>120 kg·ha−1·yr−1), and a low level of organic fertilizer (<5000 kg·ha−1·yr−1) increased the MWD by 19%, 14%, and 41%, respectively. Across the soil types and land use types, the response to the MWD was positive for red soils and paddy fields, and the organic fertilizer’s stimulatory effect was more significant than that of the chemical fertilizer. The correlation analysis showed that the response rate of the MWD was negatively correlated with the response rate of the soil pH and bulk density (BD) and positively correlated with the response rate of the soil organic carbon (SOC) and microbial mass carbon (MBC). Meanwhile, the partial least square structural equation model (PLS-SEM) showed that the meteorological factors were the main factors affecting the stability of the soil aggregates, while the secondary factors were the soil’s physical and chemical properties. Therefore, this study found that the long-term use of organic fertilizer instead of partial fertilizer is better than the use of chemical fertilizer alone, while more attention should be paid to the influence of temperature and rainfall on the stability of fertilizer in aggregate soil in the future.
Factorial Mixture Design for Properties Optimization and Modeling of Concrete Composites Incorporated with Acetates as Admixtures
Authors: Abed Ammar , Mojtahedi Alireza , Lotfollahi Yaghin Mohammad
Published: July 2023

Nowadays, admixtures are used with the aim to provide strength and durability to concrete with less water use. New and low-cost admixtures gained a large amount of consideration to mitigate the problems associated with concrete’s durability and service life without upsetting its strength properties. The current work investigates the effect of three types of acetates on the workability, density, and compressive strength of concrete, which is used in structures of the Iraqi ports that suffer from corrosion damages and deterioration owing to the aggressive marine environments. Potassium acetate (KA), calcium acetate (CaA), and ethyl acetate (EA) are incorporated with different doses (1.38–5.6 wt.% of cement) in concrete mixtures using different water/cement ratios (0.48–0.54) based on an espoused central composite experimental design. The experimental results confirmed that the average workability increased with increasing the acetate dose, particularly with CaA. The density and compressive strength of 28 days of water-cured mixtures increased with increasing acetate dose following the order: Ca > K > Ethyl acetate and decreased with increasing w/c ratio. The high rise in compressive strength and workability linked to control mixtures was 30.8% and 77.3% as well as 15.7% and 64.3% for the mixtures incorporated with 5.6 wt.% CaA and KA, respectively. While it was 14.2% and 58.3% for the mixtures incorporated with 3.5 wt.% EA. RSM was employed to optimize and model the design and hardened properties of concrete mixtures. ANOVA results predicted the same trend, which was obtained from the experimental results. The mathematical models were valued with high-regression coefficients. The highest compressive strength of 42.68 MPa has been achieved for a concrete mixture of 0.48 w/c ratio by the incorporation of 5.1 wt.% CaA through a model with R2 96.97%. The relatively low-cost acetate admixtures, particularly CaA, seemed promising for the fabrication of concrete with outstanding properties.
Identification of the Most Important Events to the Occurrence of a Disaster Using Maritime Examples
Authors: Chybowska Dorota , Chybowski Leszek , Myśków Jarosław , Manerowski Jerzy
Published: July 2023

Previous studies on maritime disasters have noted the importance of searching for their causal factors in the analysis of different types of vessels and various regions where accidents have occurred. The main objective of the study that this article presents was to develop a new approach to modelling and causal analysis of the course of maritime disasters in order to provide a holistic evaluation of this phenomenon. The novel approach adopted to support the thesis combined event network analysis and fault tree analysis (used in functional analysis for modelling the structures of systems) in the process analysis. The authors advanced a thesis that, in the studied population of disasters, there were dominant classes of basic events in each phase of the process during the course of a disaster (distinguished by means of an event network). Thirty maritime disasters that occurred between 1912 and 2019 were selected for quantitative and qualitative analyses. In each disaster, the different phases of its course were distinguished: latent, initiating, escalating, critical, and energy release. A total of 608 basic events were identified in the population, enabling the identification and characterisation of 44 classes of events. The importance of the events in each of the phases was calculated by means of importance measures. The findings confirmed the thesis. At the same time, an analysis of the importance of basic events in each phase revealed that the most common basic events are not always the most important.
A Comprehensive Study on the Performance of Various Tracker Systems in Hybrid Renewable Energy Systems, Saudi Arabia
Authors: Alanazi Mohana , Attar Hani , Amer Ayman , Amjad Ayesha , Mohamed Mahmoud , Majid Mohammed Sh. , Yahya Khalid , Salem Mohamed
Published: July 2023

To compensate for the lack of fossil fuel-based energy production systems, hybrid renewable energy systems (HRES) would be a useful solution. Investigating different design conditions and components would help industry professionals, engineers, and policymakers in producing and designing optimal systems. In this article, different tracker systems, including vertical, horizontal, and two-axis trackers in an off-grid HRES that includes photovoltaic (PV), wind turbine (WT), diesel generator (Gen), and battery (Bat) are considered. The goal is to find the optimum (OP) combination of an HRES in seven locations (Loc) in Saudi Arabia. The proposed load demand is 988.97 kWh/day, and the peak load is 212.34 kW. The results of the cost of energies (COEs) range between 0.108 to 0.143 USD/kWh. Secondly, the optimum size of the PV panels with different trackers is calculated. The HRES uses 100 kW PV in combination with other components. Additionally, the size of the PVs where 100% PV panels are used to reach the load demand in the selected locations is found. Finally, two sensitivity analyses (Sens) on the proposed PV and tracker costs and solar GHIs are conducted. The main goal of the article is to find the most cost-effective tracker system under different conditions while considering environmental aspects such as the CO2 social penalty. The results show an increase of 35% in power production from PV (compared to not using a tracker) when using a two-axis tracker system. However, it is not always cost-effective. The increase in power production when using vertical and horizontal trackers (HT) is also significant. The findings show that introducing a specific tracker for all locations depends on renewable resources such as wind speed and solar GHI, as well as economic inputs. Overall, for GHIs higher than 5.5 kWh/m2/day, the vertical tracker (VT) is cost-effective.
Optimization Method of Energy Storage Configuration for Distribution Network with High Proportion of Photovoltaic Based on Source–Load Imbalance
Authors: Zheng Fangfang , Meng Xiaofang , Xu Tiefeng , Sun Yongchang , Wang Hui
Published: July 2023

After a high proportion of photovoltaic is connected to the distribution network, it will bring some problems, such as an unbalanced source and load and voltage exceeding the limit. In order to solve them, this paper proposes an optimization method of energy storage configuration for a high-proportion photovoltaic distribution network considering source–load imbalance clustering. Taking the minimum total voltage deviation, the minimum total power loss and the minimum total operating cost as the objective function, and considering various constraints such as power balance constraints and energy storage operation constraints, a mathematical model for energy storage configuration optimization is established. Firstly, the source–load imbalance of the distribution network with a high proportion of photovoltaic is defined. Therefore, according to the 24 h photovoltaic and load data, the 24 h source–load imbalance can be obtained, and the optimal k value can be determined by the elbow rule, so that 24 h a day can be clustered into k periods by the k-means algorithm. Then, the fuzzy comprehensive evaluation method is used to determine the weight factors of each objective function in each period, and three scenes are determined according to the different amount of energy storage. Then, the hybrid particle swarm optimization algorithm proposed in this paper is used to solve the model, and the minimum objective function value, optimal position and optimal capacity of each energy storage grid in each scene are obtained. Finally, it is applied to an example of IEEE33. In the results, the total voltage deviation is increased by more than 10%, the total power loss is increased by more than 8% and the total operating cost is increased by more than 12%, which verifies the effectiveness of the proposed model.
Study on the Interaction Mechanism between Micropiles and Soil Landslides
Authors: Xu Rui , Sui Guochen , Wang Guanglu , Cheng Hui , Li Xunchang , Yang Wei , Deng Juntao , Zeng Farong
Published: July 2023

The interaction mechanism between micropiles and soil landslides is comprehensively investigated through static model tests and numerical simulations. The results show that the deformation damage mode of micropiles is mainly bending and shear damage. Because of bending deformation, cracks appear at the rear and front of the pile, respectively, about three times the pile diameter from the sliding surface. In addition, the plastic damage becomes more severe when approaching the back edge of the landslide body. Micropiles in the landslide body play a significant role in load sharing; more importantly, there is a certain pattern between the miniature piles. According to the experimental and numerical simulation results, the recommended load-sharing ratio for micropile design under static conditions is as follows: rear-row pile:middle-row pile:front-row pile = 0.411:0.348:0.241. The research in this paper reveals the good effect of micropiles against landslides, explains the mechanism of pile–soil interaction, and provides a theoretical reference for the research and application of micropiles in engineering.
The Role of Private Philanthropy in Sustainability Standards Harmonization: A Case Study
Authors: Camargo Marisa Camilher , Sarsfield Ryan , Kanninen Markku , Cashore Theresa
Published: July 2023

Voluntary sustainability standards are often inconsistent and fragmented in terms of governance, complementarity, global applicability, and traction. Calls to harmonize this space have been intensifying. The objective of this study was to better understand the role that private philanthropy has played in helping to pave the way for globally consistent and comparable sustainability-related standards in the corporate sector, through the analysis of a case study. Twenty-four interviews with 31 stakeholders were carried out between October 2021 and January 2022, using a semi-structured questionnaire. The interview responses and qualitative data were analyzed using Atlas Ti software and open coding procedures. All interviewees spoke positively about the philanthropic intervention in question, and five main themes emerged: (1) strategic relevance and effective targeting of the intervention; (2) trust-building tactics: expertise, neutrality, and facilitation; (3) flexible and strategic interventions; (4) cultivating the standards harmonization philanthropic network; (5) strategic directions for philanthropy, moving forward. Three specific tactical approaches were identified that could help to orient future philanthropic action: (a) the steering of philanthropic support (both funding and non-financial support) toward ventures where such interventions can be advantageous, relative to formalized governmental interventions; (b) the facilitation of partnerships and trust, amid delicate interpersonal and organizational politics among standard-setters and donors alike; (c) the flexibility and specificity of grant requirements, coupled with a long-term vision.
A Decision-Making Approach to Optimize COVID-19 Treatment Strategy under a Conjunctive Complex Fuzzy Environment
Authors: Faraz Muhammad Iftikhar , Alhamzi Ghaliah , Imtiaz Aneeza , Masmali Ibtisam , Shuaib Umer , Razaq Abdul , Razzaque Asima
Published: July 2023

Symmetry is a key part of the study of basic forces and particles, as well as the creation of mathematical models that help scientists in various scientific disciplines understand complex events. Scientists can figure out what a system is made of and how it works by looking at its symmetry. They can then use this information to make predictions and create new materials and technologies. Humanity has conquered many once-fatal diseases due to medical research and technological advancements. Although this progress is encouraging, there are still a great many areas that require continual human efforts. An effort is made in this article to choose the best treatment strategy to completely manage the pandemic of COVID-19 under conjunctive complex fuzzy knowledge. In this paper, the concept of conjunctive complex fuzzy relations is presented and numerous set theoretical aspects of this phenomenon are established. The investigation of this ideology is further expanded to describe different sorts of essential structural conjunctive complex fuzzy relations. Matrix and graphical representations of the formation of these newly specified relations are also provided. Moreover, this concept has been successfully employed to provide a therapy strategy for a rapid recovery from COVID-19. Furthermore, a comparative analysis is conducted to demonstrate the validity and applicability of the suggested approaches compared to existing methods.
Endothelial Glycocalyx Integrity in Treatment-Naïve People Living with HIV before and One Year after Antiretroviral Treatment Initiation
Authors: Fragkou Paraskevi C. , Ikonomidis Ignatios , Benas Dimitrios , Kavatha Dimitra , Moschopoulos Charalampos D. , Protopapas Konstantinos , Kostelli Gavriella , Thymis John , Mpirmpa Dionysia , Galani Irene , Tsakona Maria , Oikonomopoulou Chrysanthi , Theocharous George , Gorgoulis Vassilis G. , Gallos Parisis , Tsiodras Sotirios , Antoniadou Anastasia , Papadopoulos Antonios , Triantafyllidi Helen
Published: July 2023

Endothelial glycocalyx (EG) derangement has been associated with cardiovascular disease (CVD). Studies on EG integrity among people living with HIV (PLWH), are lacking. We conducted a prospective cohort study among treatment-naïve PLWH who received emtricitabine/tenofovir alafenamide, combined with either an integrase strand transfer inhibitor (INSTI, dolutegravir, raltegravir or elvitegravir/cobicistat), or a protease inhibitor (PI, darunavir/cobicistat). We assessed EG at baseline, 24 (±4) and 48 (±4) weeks, by measuring the perfused boundary region (PBR, inversely proportional to EG thickness), in sublingual microvessels. In total, 66 consecutive PLWH (60 (90.9%) males) with a median age (interquartile range, IQR) of 37 (12) years, were enrolled. In total, 40(60.6%) received INSTI-based regimens. The mean (standard deviation) PBR decreased significantly from 2.17 (0.29) μm at baseline to 2.04 (0.26) μm (p = 0.019), and then to 1.93 (0.3) μm (p < 0.0001) at 24 (±4) and 48 (±4) weeks, respectively. PBR did not differ among treatment groups. PLWH on INSTIs had a significant PBR reduction at 48 (±4) weeks. Smokers and PLWH with low levels of viremia experienced the greatest PBR reduction. This study is the first to report the benefit of antiretroviral treatment on EG improvement in treatment-naïve PLWH and depicts a potential bedside biomarker and therapeutic target for CVD in PLWH.
Community Strategy for Hepatitis B, C, and D Screening and Linkage to Care in Mongolians Living in Spain
Authors: Palom Adriana , Almandoz Edurne , Madejón Antonio , Rando-Segura Ariadna , Pérez-Castaño Ylenia , Vico Judit , Gándara Sara , Battulga Naranbaatar , Gómez-I-Prat Jordi , Riveiro-Barciela Mar , Arenas Ruiz-Tapiador Juan , García-Samaniego Javier , Buti Maria
Published: July 2023

Mongolia has one of the highest viral hepatitis infection (B, C, and D) rates in the world. The aims of this study were to increase awareness of this disease and promote viral hepatitis screening in the Mongolian community living in Spain. Through a native community worker, Mongolian adults were invited to a community program consisting of an educational activity, an epidemiological questionnaire, and rapid point-of-care testing for hepatitis B and C. In those testing positive, blood extraction was performed to determine serological and virological parameters. In total, 280 Mongolians were invited to the program and 222 (79%) attended the event: 139 were women (63%), mean age was 42 years, and 78 (35%) had viral hepatitis risk factors. Testing found 13 (5.8%) anti-HCV-positive individuals, 1 with detectable HCV RNA (0.5%), 8 HBsAg-positive (3.6%), and 7 with detectable HBV DNA (3.1%). One additional individual had HBV/HCV co-infection with detectable HBV DNA and HCV RNA. Two subjects had hepatitis B/D co-infection (0.9%). The knowledge questionnaire showed a 1.64/8-point (20.5%) increase in correct answers after the educational activity. In summary, a viral hepatitis community program was feasible and widely accepted. It increased awareness of this condition in the Mongolian community in Spain and led to linkage to care in 22 participants, 50% of whom were unaware of their infection.
Assessment of the Immune Response in Patients with Insulin Resistance, Obesity, and Diabetes to COVID-19 Vaccination
Authors: Warpechowski Jędrzej , Leszczyńska Paula , Juchnicka Dominika , Olichwier Adam , Szczerbiński Łukasz , Krętowski Adam Jacek
Published: July 2023

The SARS-CoV-19 pandemic overwhelmed multiple healthcare systems across the world. Patients with underlying medical conditions such as obesity or diabetes were particularly vulnerable, had more severe symptoms, and were more frequently hospitalized. To date, there have been many studies on the severity of SARS-CoV-2 in patients with metabolic disorders, but data on the efficiency of vaccines against COVID-19 are still limited. This paper aims to provide a comprehensive overview of the effectiveness of COVID-19 vaccines in individuals with diabetes, insulin resistance, and obesity. A comparison is made between the immune response after vaccination in patients with and without metabolic comorbidities. Additionally, an attempt is made to highlight the mechanisms of immune stimulation affected by SARS-CoV-2 vaccines and how metabolic comorbidities modulate these mechanisms. The focus is on the most common COVID-19 vaccines, which include mRNA vaccines such as Pfizer-BioNTech and Moderna, as well as viral vector vaccines such as AstraZeneca and Johnson & Johnson. Furthermore, an effort is made to clarify how the functional differences between these vaccines may impact the response in individuals with metabolic disorders, drawing from available experimental data. This review summarizes the current knowledge regarding the post-vaccination response to COVID-19 in the context of metabolic comorbidities such as diabetes, insulin resistance, and obesity.