bluuebunny/crossref_metadata_2025 huggingface dataset:
Scalable Optical Frequency Rulers with the Faraday Effect
Authors: Chang Jyun-Ping , Tsai Cheng-Mu , Ding Panfeng , Pu Jixiong , Han Pin
Published: January 2024

Optical frequency rulers (OFRs) can be used as optical wavelengths or frequency references for spectra modulation or to determine unknown wavelengths. In the past, difficult-to-perform and complicated mechanisms were used to make OFRs, such as double slits with a high-speed fluid or an external circuit to control the liquid crystal birefringence. Since then, a later research study introduced a simple structure for producing OFRs by utilizing the optical activity block and two polarizers. This achieved a movable OFR that was controllable by simply rotating one of the polarizers. However, this mechanical rotation hindered its high-speed applicability. In this article, a more advanced, scalable OFR scheme using the Faraday effect is proposed. It is controlled by varying the magnetic field intensity, which is not a mechanical method, and it can be changed at high speeds. The numerical results demonstrate that those OFR spectral ticks can be scaled to reach a higher or lower tick density, greatly benefiting the wavelength decision jobs.
Experimentation and Analysis of Intra-Cavity Beam-Splitting Method to Enhance the Uniformity of Light in the Powersphere
Authors: He Tiefeng , Pan Guobing , Zheng Guoliang , Xu Zikun , Lv Zhijian , Wu Qingyang , Wan Lili , Huang Haixuan , Shi Tianyu
Published: January 2024

The powersphere is a spherical enclosed receiver composed of multiple photovoltaic cells. It serves as a replacement for traditional photovoltaic panels in laser wireless power transmission systems for optoelectronic conversion. The ideal powersphere aims to achieve a uniform distribution of light within the cavity through infinite reflections, reducing energy losses in the circuit. However, due to the high absorption rate of the photovoltaic cells, the direct irradiation area on the inner surface of the powersphere exhibits a significantly higher light intensity than the reflected area, resulting in a suboptimal level of light uniformity and certain circuit losses. To address the aforementioned issues, a method of intra-cavity beam splitting in the powersphere is proposed. This solution aims to increase the area of direct illumination and reduce the intensity difference between direct and reflected lights, thereby improving the light uniformity on the inner surface of the powersphere. Utilizing the transformation matrix of Gaussian beams, the q parameters for each optical path with beam splitting were calculated, and the equality of corresponding q values was demonstrated. Further, based on the q parameter expression for the electric field of Gaussian beams, the intensities for each optical path were calculated, and it was demonstrated that their values are equal. Additionally, an optical software was utilized to establish a model for intra-cavity beam splitting in the powersphere. Based on this model, a beam-splitting system was designed using a semi-transparent and semi-reflective lens as the core component. The light uniformity performance of the proposed system was analyzed through simulations. To further validate the effectiveness of the calculations, design, and simulations, multiple lenses were employed to construct the beam-splitting system. An experimental platform was set up, consisting of a semiconductor laser, monocrystalline silicon photovoltaic cells, beam expander, Fresnel lens, beam-splitting system, and powersphere. An experimental verification was conducted, and the results aligned with the theoretical calculations and simulated outcomes. The above theory, simulations, and experiments demonstrate that the intra-cavity beam-splitting method effectively enhances the optical uniformity within the powersphere.
Role of Microbes in Alleviating Crop Drought Stress: A Review
Authors: Gu Zechen , Hu Chengji , Gan Yuxin , Zhou Jinyan , Tian Guangli , Gao Limin
Published: January 2024

Drought stress is an annual global phenomenon that has devastating effects on crop production, so numerous studies have been conducted to improve crop drought resistance. Plant-associated microbiota play a crucial role in crop health and growth; however, we have a limited understanding of the key processes involved in microbiome-induced crop adaptation to drought stress. In this review, we summarize the adverse effects of drought stress on crop growth in terms of germination, photosynthesis, nutrient uptake, biomass, and yield, with a focus on the response of soil microbial communities to drought stress and plant-microbe interactions under drought stress. Moreover, we review the morpho-physiological, biochemical, and molecular mechanisms underlying the mitigation effect of microbes on crop drought stress. Finally, we highlight future research directions, including the characterization of specific rhizosphere microbiome species with corresponding root exudates and the efficiency of rhizobacteria inoculants under drought conditions. Such research will advance our understanding of the complex interactions between crops and microbes and improve crop resistance to drought stress through the application of beneficial drought-adaptive microbes.
Vitex Genus as a Source of Antimicrobial Agents
Authors: Islam Zohorul , Caldeira Gonçalo I. , Caniça Manuela , Islam Nurul , Silva Olga
Published: January 2024

Vitex L. is the largest genus of the Lamiaceae family, and most of its species are used in the traditional medicinal systems of different countries. A systematic review was conducted, according to the PRISMA methodology, to determine the potential of Vitex plants as sources of antimicrobial agents, resulting in 2610 scientific publications from which 141 articles were selected. Data analysis confirmed that Vitex species are used in traditional medicine for symptoms of possible infectious diseases. Conducted studies showed that these medicinal plants exhibited in vitro antimicrobial activity against Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus. Vitex agnus-castus L. and Vitex negundo L. have been the most studied species, not only against bacterial strains but also against fungi such as Aspergillus niger and Candida albicans, viruses such as HIV-1, and parasites such as Plasmodium falciparum. Natural products like agnucastoside, negundol, negundoside, and vitegnoside have been identified in Vitex extracts and their antimicrobial activity against a wide range of microbial strains has been determined. Negundoside showed significant antimicrobial activity against Staphylococcus aureus (MIC 12.5 µg/mL). Our results show that Vitex species are potential sources of new natural antimicrobial agents. However, further experimental studies need to be conducted.
Design and Development of an Edible Coating for a Ready-to-Eat Fish Product
Authors: Bremenkamp Ina , Sousa-Gallagher Maria J.
Published: January 2024

The application of chitosan and alginate coatings for a ready-to-eat (RTE) baked fish product was studied. An experimental design was used to investigate the effect of coating a polysaccharide concentration and glycerol addition on the safety (microbial growth) and quality (water loss and lipid oxidation) of an RTE fish product under optimal and abused storage conditions. The results showed that a chitosan coating with 1% (w/v) chitosan in 1% (v/v) acetic acid and 15% (w/w chitosan) glycerol, or a 1% (w/v) alginate coating with no glycerol and no crosslinking, showed the best performance in controlling the tested safety and quality parameters. The desirability method was used to identify the shelf lives of chitosan, alginate, and double-coated RTE products. The chitosan-coated samples showed the best performance with a three-fold shelf-life extension compared to the uncoated products stored at 4 °C. Moreover, the tested coatings demonstrated their ability to provide protective functions under abused storage conditions. These results strongly suggest that edible coatings have significant potential in enhancing the shelf life and safety of ready-to-eat (RTE) fish products.
Polymers and Biomaterials for Posterior Lamella of the Eyelid and the Lacrimal System
Authors: Wu Kevin Y. , Fujioka Jamie K. , Goodyear Emilie , Tran Simon D.
Published: January 2024

The application of biopolymers in the reconstruction of the posterior lamella of the eyelid and the lacrimal system marks a significant fusion of biomaterial science with clinical advancements. This review assimilates research spanning 2015 to 2023 to provide a detailed examination of the role of biopolymers in reconstructing the posterior lamella of the eyelid and the lacrimal system. It covers the anatomy and pathophysiology of eyelid structures, the challenges of reconstruction, and the nuances of surgical intervention. This article progresses to evaluate the current gold standards, alternative options, and the desirable properties of biopolymers used in these intricate procedures. It underscores the advancements in the field, from decellularized grafts and acellular matrices to innovative natural and synthetic polymers, and explores their applications in lacrimal gland tissue engineering, including the promise of 3D bioprinting technologies. This review highlights the importance of multidisciplinary collaboration between material scientists and clinicians in enhancing surgical outcomes and patient quality of life, emphasizing that such cooperation is pivotal for translating benchtop research into bedside applications. This collaborative effort is vital for restoring aesthetics and functionality for patients afflicted with disfiguring eyelid diseases, ultimately aiming to bridge the gap between innovative materials and their clinical translation.
Prediction of the Tribological Properties of Polytetrafluoroethylene Composites Based on Experiments and Machine Learning
Authors: Yan Yingnan , Du Jiliang , Ren Shiwei , Shao Mingchao
Published: January 2024

Because of the complex nonlinear relationship between working conditions, the prediction of tribological properties has become a difficult problem in the field of tribology. In this study, we employed three distinct machine learning (ML) models, namely random forest regression (RFR), gradient boosting regression (GBR), and extreme gradient boosting (XGBoost), to predict the tribological properties of polytetrafluoroethylene (PTFE) composites under high-speed and high-temperature conditions. Firstly, PTFE composites were successfully prepared, and tribological properties under different temperature, speed, and load conditions were studied in order to explore wear mechanisms. Then, the investigation focused on establishing correlations between the friction and wear of PTFE composites by testing these parameters through the prediction of the friction coefficient and wear rate. Importantly, the correlation results illustrated that the friction coefficient and wear rate gradually decreased with the increase in speed, which was also proven by the correlation coefficient. In addition, the GBR model could effectively predict the tribological properties of the PTFE composites. Furthermore, an analysis of relative importance revealed that both load and speed exerted a greater influence on the prediction of the friction coefficient and wear rate.
Highly Stretchable Thermoplastic Polyurethane Separators for Li-Ion Batteries Based on Non-Solvent-Induced Phase Separation Method
Authors: Kim Tae Hyung , Kim MinSu , Kim Eun Ji , Ju Minu , Kim Ji Soo , Lee Seung Hee
Published: January 2024

The growing interest in wearable and portable devices has stimulated the need for flexible and stretchable lithium-ion batteries (LiBs). A crucial component in these batteries is the separator, which provides a pathway for Li-ion transfer and prevents electrode contact. In a flexible and stretchable LiB, the separator must exhibit stretchability and elasticity akin to its existing counterparts. Here, we developed a non-modified thermoplastic polyurethane (TPU) separator using the non-solvent induced phase separation (NIPS) technique. We compared their performance with commercially available polypropylene (PP) separators. Our results demonstrate that TPU separators exhibit superior elasticity based on repeated stretch/release tests with excellent thermal stability and electrolyte wettability. Furthermore, our findings confirm that TPU separators, even after being repeatedly stretched and released, can function effectively without severe damage in a fabricated coin cell LiB with high oxidative stability, as evidenced by linear sweep voltammetry, like commercially available separators.
Epoxy-Based Blend Formulation for Dual Curing in Liquid Crystal Display 3D Printing: A Study on Thermomechanical Properties Variation for Enhanced Printability
Authors: Tosto Claudio , Saitta Lorena , Latteri Alberta , Cicala Gianluca
Published: January 2024

The aim of this study was to explore the thermal properties of epoxy–acrylate blends for the liquid crystal display (LCD) 3D printing technique. Starting from an epoxy–acrylate blend with a ratio of epoxy to acrylate of 50:50, the effect of adding a reactive monofunctional epoxy diluent was evaluated. The diluent was a resin composed by oxirane, mono[(C12-14 alkyl) methyl] derivatives selected for its low viscosity (i.e., 1.8 Poise) at room temperature and its reactivity. The diluent content varied from 15 to 25 wt% and, for all the formulation, double curing cycles, where thermal curing followed photocuring, were studied. The effect of different curing temperatures was also evaluated. The control of the diluent content and of the curing temperature allowed tailoring of the thermomechanical resin properties while improving the resin’s processability. The glass transition ranged from 115.4 °C to 90.8 °C depending on the combination of diluent content and post-curing temperature. The resin developed displayed a faster processing time tested on a reference part with printing time of 4 h and 20 min that was much lower than the printing times (7 and 16 h) observed for the starting formulations.
Synthesis and Properties of a Novel Levulinic Acid-Based Environmental Auxiliary Plasticizer for Poly(vinyl chloride)
Authors: You Zeyu , Yu Min , Fu Renli , Nie Xiaoan , Chen Jie
Published: January 2024

Herein, a bio-based plasticizer ketalized tung oil butyl levulinate (KTBL) was developed using methyl eleostearate, a derivative of tung oil, and butyl levulinate. KTBL can be used as an auxiliary plasticizer to partially replace traditional plasticizer. The plasticizer has a ketone structure, an ester base, and a long linear chain. It was mixed with dioctyl phthalate (DOP), and the effect of the plasticizer KTBL as an auxiliary plasticizer on the plasticization of poly(vinyl chloride) (PVC) was studied. Their compatibility and plasticizing effect were evaluated using dynamic–mechanical thermal analysis (DMA), mechanical property analysis, and thermogravimetric analysis (TGA). The results demonstrate that when the KTBL to DOP ratio is 1:1, the blended sample with KTBL exhibits superior mechanical performance compared to pure DOP, resulting in an increased elongation at break from 377.47% to 410.92%. Moreover, with the increase in KTBL content, the durability is also significantly improved. These findings suggest that KTBL can serve as an effective auxiliary plasticizer for PVC, thereby reducing the reliance on DOP.
Compatibilization of Cellulose Nanocrystal-Reinforced Natural Rubber Nanocomposite by Modified Natural Rubber
Authors: Jantachum Punyarat , Phinyocheep Pranee
Published: January 2024

Due to global warming and environmental concerns, developing a fully bio-based nanocomposite is an attractive issue. In this work, the cellulose nanocrystals (CNCs) extracted from Luffa cylindrica, a renewable resource, were explored as a bio-based reinforcing filler in natural rubber (NR) nanocomposites. In addition, modified natural rubber was explored as a potential compatibilizer to assist the filler dispersion in the rubber nanocomposite. The effect of the CNC content (0–15 phr) on cure characteristics and the mechanical, dynamic, and thermal properties of NR/CNC nanocomposites was investigated. The results showed that the scorch time and cure time of the nanocomposites increased with increased CNC contents. The optimum tensile strength of NR nanocomposites having 5 phr of the CNC (NR-CNC5) was 20.60% higher than the corresponding unfilled NR vulcanizate, which was related to the increased crosslink density of the rubber nanocomposite. The incorporation of oxidized-degraded NR (ODNR) as a compatibilizer in the NR-CNC5 nanocomposite exhibited a considerably reduced cure time, which will lead to energy conservation during production. Moreover, the cure rate index of NR-CNC5-ODNR is much higher than using a petroleum-based silane coupling agent (Si69) as a compatibilizer in the NR-CNC5 nanocomposite. The good filler dispersion in the NR-CNC5 nanocomposite compatibilized by ODNR is comparable to the use of Si69, evidenced by scanning electron microscopy. There is, therefore, a good potential for the use of modified NR as a bio-based compatibilizer for rubber nanocomposites.
Virtual Test Beds for Image-Based Control Simulations Using Blender
Authors: Leonard Akkarakaran Francis , Gjonaj Govanni , Rahman Minhazur , Durand Helen E.
Published: January 2024

Process systems engineering research often utilizes virtual testbeds consisting of physicsbased process models. As machine learning and image processing become more relevant sensing frameworks for control, it becomes important to address how process systems engineers can research the development of control and analysis frameworks that utilize images of physical processes. One method for achieving this is to develop experimental systems; another is to use software that integrates the visualization of systems, as well as modeling of the physics, such as three-dimensional graphics software. The prior work in our group analyzed image-based control for the small-scale example of level in a tank and hinted at some of its potential extensions, using Blender as the graphics software and programming the physics of the tank level via the Python programming interface. The present work focuses on exploring more practical applications of image-based control. Specifically, in this work, we first utilize Blender to demonstrate how a process like zinc flotation, where images of the froth can play a key role in assessing the quality of the process, can be modeled in graphics software through the integration of visualization and programming of the process physics. Then, we demonstrate the use of Blender for testing image-based controllers applied to two other processes: (1) control of the stochastic motion of a nanorod as a precursor simulation toward image-based control of colloidal self-assembly using a virtual testbed; and (2) controller updates based on environment recognition to modify the controller behavior in the presence of different levels of sunlight to reduce the impacts of environmental disturbances on the controller performance. Throughout, we discuss both the setup used in Blender for these systems, as well as some of the features when utilizing Blender for such simulations, including highlighting cases where non-physical parameters of the graphics software would need to be assumed or tuned to the needs of a given process for the testbed simulation. These studies highlight benefits and limitations of this framework as a testbed for image-based controllers and discuss how it can be used to derive insights on image-based control functionality without the development of an experimental testbed.
Biofilm Formation in Water Distribution Systems
Authors: Erdei-Tombor Patrícia , Kiskó Gabriella , Taczman-Brückner Andrea
Published: January 2024

A biofilm is a biologically active matrix attached to the surface of cells and their extracellular products. As they are a mixture of many microorganisms, the microbiological activity of biofilms varies according to their position in the aggregate. With particular emphasis on drinking water distribution systems, this review focuses on the process of biofilm formation, associated bacteria, chlorine resistance of bacteria, and the predominant surface materials. We have compiled studies on the bacteria in drinking water distribution systems and their interactions with biofilm formation on different materials, and we also analysed the chlorine-resistant bacteria and their problems in the water networks. The materials used in the drinking water network are significantly affected by the disinfection method used to produce the biofilm that adheres to them. Some studies propose that the material is inconsequential, with the disinfection process being the most significant factor. Studies suggest that materials based on plastics (such as PVC and HDPE) tend to be more effective in controlling biofilm formation or removal than those based on metals (such as stainless steel), which have been found to be less effective in some instances. Chlorine-resistant strains are becoming more and more common in drinking water networks, resulting in the occurrence of diseases such as typhus and cholera.
Quality of Mixedness Using Information Entropy in a Counter-Current Three-Phase Bubble Column
Authors: Prakash Ritesh , Majumder Subrata Kumar , Lee Jinkee , Nedeltchev Stoyan
Published: January 2024

Knowledge of mixing phenomena is of great value in the mineral and other chemical and biochemical industries. This work aims to analyze the quality of mixedness (QM), the intrinsic mass transfer (MT) number, and the MT efficiency based on information entropy theory in the counter-current microstructured slurry bubble column. A thorough analysis is conducted to assess the effects of particle loading, gas and slurry velocity, and axial variation on the QM. The range of gas velocity, slurry velocity, particle size, and particle loading was 0.011–0.075 m/s, 0.018–0.058 m/s, 242.72–408.31 μm, and 15.54–88.94 kg/m3, respectively. QM is a time-dependent parameter, and the concept of contact time has been used for scale-up purposes. The maximum QM was achieved at dimensionless times of 0.40 × 10−3, 0.15 × 10−3, and 0.85 × 10−3 for the maximum superficial gas velocity, particle loading, and axial height, respectively. The gas velocity positively influenced both the intrinsic MT number and its efficiency. In contrast, the slurry velocity and particle loading had a negative effect. The present theoretical analysis will pave the path for industrial process intensification in counter-current flow systems.
The Textural and Physical Characteristics of Red Radishes Based on a Puncture Test
Authors: Lupu Mariana , Nedeff Valentin , Panainte-Lehadus Mirela , Mosnegutu Emilian , Tomozei Claudia , Chitimus Dana , Rusu Dragos-Ioan
Published: January 2024

Texture is an important indication of the quality of food products, and the analysis of texture involves the measurement of their response when subjected to mechanical forces, such as cutting, scissoring, chewing, and compression or stretching. There is a close correlation between the texture of agri-food products and their mechanical properties. In this study, the textural characteristics of red radish roots were analyzed under different storage conditions using a penetration test. The physical parameters analyzed are the skin strength and elasticity, breaking point, ripening and softening profile, and flesh firmness. The results of the breaking point after the products’ storage at room temperature (tested after one, two, and three days, respectively) are: 184.96 N, 151.29 N, and 154.42 N, respectively; for radishes stored at a temperature of 2.8 °C, the breaking point is: 132.12 N, 109.76 N, and 141.16 N, respectively. The lowest value of firmness is recorded for the radishes tested fresh at 78.98 N, and the highest value of firmness is for the sample of specimens kept at laboratory temperature, that is, 103.96 N. The epidermal elasticity also undergoes significant changes during the experiment, starting from an epidermal elasticity of 2.14 mm (fresh sample) to a value of 4.15 mm (for the sample stored at laboratory temperature for three days). The experimental determinations indicated that the highest value of the penetration force of 184.1 N was obtained for the product stored at room temperature, and the lowest value of 109.76 N was obtained for the product stored at 2.8 °C.
The Influence of Shear-Thinning Characteristics on Multiphase Pump Vortex Structure Evolution, Pressure Fluctuation, and Gas-Solid Distribution
Authors: Chen Long , Yang Yingxin , Peng Cancan , Zhang Xiaodong , Gong Yan
Published: January 2024

In the current landscape of natural gas hydrate extraction, the lifting pump assumes a pivotal role as the essential equipment for conveying subsea fluidized hydrate slurry to the wellhead. The inherent shear-thinning characteristics of natural gas hydrate slurry, compounded by the complex multiphase flow conditions of the “gas-liquid-solid” system, present significant challenges to the operational efficiency and stability of the lifting pump. Consequently, this study adopts a hybrid approach, combining experimental and numerical simulations, to comparatively investigate the impact of non-Newtonian and viscous Newtonian fluids on the hydraulic performance, vortex structure evolution, and induced pressure fluctuations in a multiphase pump. Concurrently, a comparative analysis is conducted on the influence of these two fluid types on the distribution patterns of the “gas-solid” two-phase system. The research findings indicate that the apparent viscosity variations are more pronounced in the diffuser region compared to the impeller region. Under non-Newtonian fluid conditions, two separation vortices emerge at the trailing edge of the diffuser, as opposed to a single separation vortex in the viscous Newtonian fluid, with the latter exhibiting a smaller vortex structure scale. Moreover, the shear-thinning characteristics intensify the interaction between the separated vortex and the mainstream, resulting in an exacerbation of pressure fluctuations. In contrast to the viscous Newtonian fluid, the rotor–stator interaction and shear-thinning characteristics play a predominant role in pressure fluctuations, with shear-thinning attributes giving rise to low-frequency pressure fluctuations. Additionally, shear-thinning characteristics significantly influence the distribution behavior of the gas-solid two-phase flow.
Intelligent Classification of Volcanic Rocks Based on Honey Badger Optimization Algorithm Enhanced Extreme Gradient Boosting Tree Model: A Case Study of Hongche Fault Zone in Junggar Basin
Authors: Chen Junkai , Deng Xili , Shan Xin , Feng Ziyan , Zhao Lei , Zong Xianghua , Feng Cheng
Published: January 2024

Lithology identification is the fundamental work of oil and gas reservoir exploration and reservoir evaluation. The lithology of volcanic reservoirs is complex and changeable, the longitudinal lithology changes a great deal, and the log response characteristics are similar. The traditional lithology identification methods face difficulties. Therefore, it is necessary to use machine learning methods to deeply explore the corresponding relationship between the conventional log curve and lithology in order to establish a lithology identification model. In order to accurately identify the dominant lithology of volcanic rock, this paper takes the Carboniferous intermediate basic volcanic reservoir in the Hongche fault zone as the research object. Firstly, the Synthetic Minority Over-Sampling Technique–Edited Nearest Neighbours (SMOTEENN) algorithm is used to solve the problem of the uneven data-scale distribution of different dominant lithologies in the data set. Then, based on the extreme gradient boosting tree model (XGBoost), the honey badger optimization algorithm (HBA) is used to optimize the hyperparameters, and the HBA-XGBoost intelligent model is established to carry out volcanic rock lithology identification research. In order to verify the applicability and efficiency of the proposed model in volcanic reservoir lithology identification, the prediction results of six commonly used machine learning models, XGBoost, K-nearest neighbor (KNN), gradient boosting decision tree model (GBDT), adaptive boosting model (AdaBoost), support vector machine (SVM) and convolutional neural network (CNN), are compared and analyzed. The results show that the HBA-XGBoost model proposed in this paper has higher accuracy, precision, recall rate and F1-score than other models, and can be used as an effective means for the lithology identification of volcanic reservoirs.
Dynamic Pressure Analysis of Shale Gas Wells Considering Three-Dimensional Distribution and Properties of the Hydraulic Fracture Network
Authors: Kang Lixia , Wang Gaocheng , Zhang Xiaowei , Guo Wei , Liang Bin , Jiang Pei , Liu Yuyang , Gao Jinliang , Liu Dan , Yu Rongze , Sun Yuping
Published: January 2024

A major challenge in transient pressure analysis for shale gas wells is their complex transient flow behavior and fracturing parameters. While numerical simulations offer high accuracy, analytical models are attractive for transient pressure analysis due to their high computational efficiency and broad applicability. However, traditional analytical models are often oversimplified, making it difficult to capture the complex seepage system, and three-dimensional fracture characteristics are seldom considered. To address these limitations, this study presents a comprehensive hybrid model that characterizes the transient flow behavior and analyzes the pressure response of a fractured shale gas well with a three-dimensional discrete fracture. To achieve this, the hydraulic fracture is discretized into several panels, and the transient flow equation is numerically solved using the finite difference method. Based on the Langmuir adsorption isotherm and the pseudo-steady diffusion in matrix and Darcy flow in the network of micro-fractures, a reservoir model is established, and the Laplace transformation is adopted to solve the model analytically. The transient responses are obtained by dynamically coupling the flow in the reservoir and the discrete fracture. The precision of the proposed model is validated using the commercial numerical simulator, Eclipse. A series of transient pressure dynamic curves are drawn to make a precise observation of different flow regimes, and the effects of several parameters on transient pressure response are also examined. The results show that the shale gas well testing interpretation curves comprise nine flow stages. The pressure drop of shale gas reservoirs is lower than that of conventional gas reservoirs due to the replenishment of desorbed gas. The artificial fracture flow capacity, fracture length, and height are the main engineering factors affecting the pressure responses of shale gas wells. Maximizing the degree and scope of reconstruction can enhance the gas well production capacity during fracturing construction. The research results also indicate that our model is a reliable semi-analytical model for well test interpretations in real case studies.
Optimization of Ternary Activator for Enhancing Mechanical Properties of Carbonized Cementitious Material Based on Circulating Fluidized Bed Fly Ash
Authors: Xu Nuo , Ma Suxia , Wang Nana , Feng Yuchuan , Liu Yunqi , Ren Ke , Bai Shanshui
Published: January 2024

In this study, circulating fluidized bed fly ash (CFBFA) non-sintered ceramsite was innovatively developed. The CFBFA was addressed by adding ternary activator (including cement, hydrated lime, and gypsum) to prepare ceramsite. In the curing process, the use of power plant flue gas for curing not only captured greenhouse gas CO2, but also enhanced the compressive strength of the ceramsite. The compressive strength of the composite gravels prepared by the CFBFA was modeled using a novel approach that employed the response surface methodology (RSM) and artificial neural network (ANN) coupled with genetic algorithm (GA). Box–Behnken design (BBD)-RSM method was used for the independent variables of cement content, hydrated lime content, and gypsum content. The resulting quadratic polynomial model had an R2 value of 0.9820 and RMSE of 0.21. The BP-ANN with a structure of 3-10-1 performed the best and showed better prediction of the response than the BBD-RSM model, with an R2 value of 0.9932 and RMSE of 0.19. The process parameters were optimized using RSM optimization tools and GA. Validation experiments showed that the GA-ANN prediction results were more accurate than the BBD-RSM results.
Optimized Scheduling of Integrated Energy Systems with Integrated Demand Response and Liquid Carbon Dioxide Storage
Authors: Zhang Nan , Chen Jie , Liu Bin , Ji Xiaoning
Published: January 2024

Energy storage technology can well reduce the impact of large-scale renewable energy access to the grid, and the liquid carbon dioxide storage system has the characteristics of high energy storage density and carries out a variety of energy supply, etc. Therefore, this paper proposes an integrated energy system (IES) containing liquid carbon dioxide storage and further exploits the demand-side regulation potential on the basis of which an integrated demand response model is proposed to consider the cooling, heating, and electricity loads. On this basis, an IES optimal scheduling model with the lowest total system operating cost as the objective function is established, the Yalmip toolbox and Cplex commercial solver are used to solve the algorithms, and the optimal scheduling results are obtained for electricity, heat, and cold under four scenarios, and it is proved through comparative analyses that the model and scheduling strategy established in this paper can optimize the load profile, realize peak shaving and valley filling, and have good economic benefits. Then, by analyzing the impact of the initial pressure of the high-pressure storage tank and fluctuating electricity price on the liquid carbon dioxide energy storage system, the system model established in this paper has good stability. Finally, for the comprehensive demand response model established in this paper, the impact of the demand response of different types of loads on the economy of the system is analyzed in depth from the perspective of economic benefits.
Evaluation of the Landfill Storage Capacity in Slovakia, Compared to the EU Situation
Authors: Šimková Zuzana , Taušová Marcela , Čulková Katarína , Tauš Peter , Shyp Danylo , Krasniči David , Novotná Simona
Published: January 2024

The circular economy and efficient use of resources gained importance in the context of sustainable development. The paper aims to evaluate the development of landfilling in Slovakia. The next goal is to assess the trend in compared with the EU’s situation. The presented research presents a continuation of previous research in the area of waste recycling in Slovakia, pointing to the waste and landfilling, which is deserving of analysis from a long-term perspective. The research is carried out via data collection at the EU level by recording continuously published values. The paper’s results are processed in statistical software. Considering regional development, landfilling in Slovakia is followed up according to the geographical units of the entire country. The results shown here show that a higher recycling capacity is required and Slovakia should decrease its level of landfill. Such results can be used in the waste treatment area, protection of the living environment and sustainable development of regions.
The Mediation of Coloniality in Decolonisation Developments in South African Theological Education
Authors: Naidoo Marilyn
Published: January 2024

The imperial nature of Christianity structured around colonialism, white supremacy, and apartheid was governed by racially motivated logics that fundamentally define the idea of who could be human. Decades later, the uncomfortable emphasis on decoloniality in South African theological education arises in a contested space despite the need to decentre white, Western methods, interpretations, and experiences. Academic readiness and ownership regarding the implementation of decolonisation initiatives constitute a significant obstacle. They highlight how coloniality mediates and attempts to erase decolonising praxis. This article employs the theoretical framing of Grosfoguel’s analysis of the coloniality of power, of knowledge, and of being, surveys recent educational developments in theological education towards redress to reveal a hesitancy and considers the perspective change of educators towards decolonisation praxis. This article underscores a contextual challenge for the legitimacy of decolonialisation and the need to restore its significance amidst the slow pace of educational transformation in theological education.
The Donna de Fora: A Sicilian Fairy–Witch in the Early Modern Age
Authors: Geremia Claudia Stella
Published: January 2024

In this paper, my objective is to delve into the history of women accused of practicing witchcraft in Sicily during the early modern period. This investigation draws upon documented evidence from the Spanish Inquisition spanning from 1516 to 1782, along with archival records and the ethnographic works of nineteenth-century scholars. The focal point of my research is the enigmatic figure known as donna de fora (the ladies from outside) in the Italian context. To illuminate this subject, I employ an analysis of seventeenth-century Inquisition trial records and oral traditions documented by anthropologist Giuseppe Pitrè in the late nineteenth century. The donne de fora represent a distinctive and intriguing group as this term appears exclusively within the Inquisitorial records of Sicily. They were perceived as supernatural entities, characterized as “part witches, part fairies”. According to beliefs of the time, these women’s spirits would depart from their bodies during sleep to convene with higher-ranking fairies. Notably, the trials and the Edict of the Diocese of Girgenti (Agrigento) in 1656 document that the most significant gatherings of these figures occurred during the night of Saint John, between the 23rd and 24th of June. Through an examination of trial records, we gain insights into how these women were perceived by their contemporaries, as well as an understanding of their societal roles and the ritual practices they engaged in. Moving forward to the late nineteenth century, ethnologist Giuseppe Pitrè conducted a comprehensive study of local rituals and popular folklore, and he collected various objects and documents related to supernatural beliefs, including those associated with the donne de fora in the regions around Palermo. My research is centered on archival records containing Pitrè’s notes, unpublished drafts, and correspondence with scholars in Italy and Europe discussing this phenomenon. Based on my findings, I aim to establish a connection between Pitrè’s material discoveries and contemporary beliefs regarding donne de fora and witchcraft in Sicily.
A Historical Review of the Comparative Study of Mohism and Christianity during the Late Qing and Republican China Periods
Authors: Pang Wing Yin
Published: January 2024

This study provides a fresh understanding of the historical development shaping comparative studies between Christianity and Mohism during the late Qing and Republican China periods. It traces the foundation of these studies to both the idea that ‘Western knowledge originated from Mohism’ and to the Mohism studies by the Qian-Jia School 乾嘉學派 during the Qing Dynasty. This study spotlights the groundbreaking proposition by Zou Boqi 鄒伯奇 in 1844, who first suggested that Western knowledge, including Christianity, originated from Mohism, a widely accepted view among Chinese literati. The article then explores the paradigm shift initiated by Liang Qichao 梁啓超, influenced by Sun Yirang 孫詒讓 and his Mozi Jiangu 墨子閒詁 (The Works of Mozi with Commentaries), which broadened the comparative perspective. The significant influence of the Qian-Jia School’s Mohism studies on both Chinese and non-Chinese scholars is analyzed, along with the diverse approaches and contributions of key figures like Joesph Edkins, James Legge, Ernst Faber, Alexandra David-Néel, Daisetz Teitaro Suzuki, Huang Zhiji 黃治基, Wang Zhixin 王治心, Zhang Chunyi 張純一, Mei Yi-Pao 梅貽寶, and Wu Leichuan 吳雷川. The article underscores these scholarly groups’ dynamic interplay and varied objectives, shaping a vibrant and contentious academic landscape.
Quadratic Unconstrained Binary Optimization Approach for Incorporating Solvency Capital into Portfolio Optimization
Authors: Turkalj Ivica , Assadsolimani Mohammad , Braun Markus , Halffmann Pascal , Hegemann Niklas , Kerstan Sven , Maciejewski Janik , Sharma Shivam , Zhou Yuanheng
Published: January 2024

In this paper, we consider the inclusion of the solvency capital requirement (SCR) into portfolio optimization by the use of a quadratic proxy model. The Solvency II directive requires insurance companies to calculate their SCR based on the complete loss distribution for the upcoming year. Since this task is, in general, computationally challenging for insurance companies (and therefore, not taken into account during portfolio optimization), employing more feasible proxy models provides a potential solution to this computational difficulty. Here, we present an approach that is also suitable for future applications in quantum computing. We analyze the approximability of the solvency capital ratio in a quadratic form using machine learning techniques. This allows for an easier consideration of the SCR in the classical mean-variance analysis. In addition, it allows the problem to be formulated as a quadratic unconstrained binary optimization (QUBO), which benefits from the potential speedup of quantum computing. We provide a detailed description of our model and the translation into a QUBO. Furthermore, we investigate the performance of our approach through experimental studies.
Evaluation of an Adaptive Soil Moisture Bias Correction Approach in the ECMWF Land Data Assimilation System
Authors: Fairbairn David , de Rosnay Patricia , Weston Peter
Published: January 2024

Satellite-derived soil moisture (SM) observations are widely assimilated in global land data assimilation systems. These systems typically assume zero-mean errors in the land surface model and observations. In practice, systematic differences (biases) exist between the observed and modelled SM. Commonly, the observed SM biases are removed by rescaling techniques or via a machine learning approach. However, these methods do not account for non-stationary biases, which can result from issues with the satellite retrieval algorithms or changes in the land surface model. Therefore, we test a novel application of adaptive SM bias correction (BC) in the European Centre for Medium Range Weather Forecasts (ECMWF) land data assimilation system. A two-stage filter is formulated to dynamically correct biases from satellite-derived active ASCAT C-band and passive L-band SMOS surface SM observations. This complements the operational seasonal rescaling of the ASCAT observations and the SMOS neural network retrieval while allowing the assimilation to correct subseasonal-scale errors. Experiments are performed on the ECMWF stand-alone surface analysis, which is a simplified version of the integrated forecasting system. Over a 3 year test period, the adaptive BC reduces the seasonal-scale (observation−forecast) departures by up to 20% (30%) for the ASCAT (SMOS). The adaptive BC leads to (1) slight improvements in the SM analysis performance and (2) moderate but statistically significant reductions in the 1–5 day relative humidity forecast errors in the boundary layer of the Northern Hemisphere midlatitudes. Future work will test the adaptive SM BC in the full integrated forecasting system.
Evaluating Land Use and Ecological Patterns in Xiong’an New Area of China with Machine Learning Methodology
Authors: Ouyang Qing , Pan Jiayi
Published: January 2024

The Xiong’an New Area, following the precedent of the Shenzhen Special Economic Zone and Shanghai Pudong New Area, marks a significant development. This study introduces a method to optimize the feature variable selection for Sentinel-2 images from 2016 to 2022, aiming for precise land-use classification in Xiong’an using machine learning. The classification reveals substantial growth in the infrastructure and aquatic areas in Rongcheng and Xiongxian counties, outpacing Anxin from 2016 to 2022. The Remote Sensing-Based Ecological Index (RSEI) indicates a generally stable yet improving ecological landscape, especially in denser areas like Xiongxian and Rongcheng, aligning regional development with ecological enhancement. EOF analysis shows a spatial ecological division, with positive RSEI values in the western regions and negative values in the east, along with temporal fluctuations indicating a decline in the west and an increase in the east since 2017. Additionally, the RSEI’s short-cycle fluctuations emphasize the dynamic ecological state of the area, influenced by both long-term trends and transient factors.
Investigation of Submerged MEMS Ultrasonic Sensors for Underwater Obstacle Avoidance Application
Authors: Wang Zhihao , Zhang Wendong , Wang Renxin , He Changde , Liu Shurui , Wang Jingwen , Li Zhaodong , Lu Xiaoxing , Qin Yun , Zhang Guojun , Cui Jiangong , Yang Yuhua , Jia Licheng
Published: January 2024

Ultrasound is a powerful and versatile technology that has been applied extensively in medicine and scientific research. The development of miniature underwater robots focuses on achieving specific tasks, such as surveys and inspections in confined spaces. However, traditional sonar has limited use in micro underwater robots due to its large size and heavy power demands. Conversely, capacitive micromechanical ultrasonic transducers (CMUTs) offer various advantages, including a wide bandwidth, compact size, and integration feasibility. These attributes make CMUTs a candidate for obstacle avoidance in micro underwater robots. Hence, a novel CMUT structure using Si-Si bonding is proposed. In this design, a membrane isolation layer replaces the cavity bottom isolation layer, simplifying the process and improving bond reliability. A finite element model of the CMUT was constructed in COMSOL and numerically assessed for the CMUT’s operating frequency, collapse voltage, and submerged depth. The CMUT, manufactured using micro-electro-mechanical system (MEMS) technology, undergoes waterproofing with PDMS—A material with similar acoustic impedance to water and corrosion resistance. Underwater tests reveal the CMUT’s resonant frequency in water as approximately 2 MHz, with a −3 dB bandwidth of 108.7%, a transmit/receive beam width of 7.3°, and a standard deviation of measured distance from the true distance of less than 0.05. These outcomes suggest that CMUTs hold promise in obstacle avoidance applications for fish-shaped underwater robots.