bluuebunny/crossref_metadata_2025 huggingface dataset:
Beginning Teachers Navigating Identity Development Transitions: Identity Motives and Commitment to Teaching
Authors: Abramson Lori L. , Schachter Elli P.
Published: October 2024

Beginning teachers (preservice and novice) must develop a resilient professional identity, yet high early attrition rates indicate the need for additional support in this process. Many attrition studies focus on external factors; few address teacher identity. According to developmental psychologists, identity commitments are concretized in a stepwise process, first by tentatively making them, and then by evaluating them. Most preservice and novice teachers are in a transitional stage, as they explore whether tentative commitments fit their sense of self. Our research tests the proposition that such exploration is often focused on determining whether a teaching career will satisfy their identity motives. We interviewed and collected self-reported written stories from 154 interns and novice teachers. Participants discussed their career choice in an initial interview and in a questionnaire focusing on recent, identity-relevant significant events administered at three points in time over a year. These career choice and written, field-based significant event stories underwent content analysis for the presence of identity motives, guided by a codebook developed for this research. This paper describes two central and innovative findings. First, identity motives are, indeed, present and highly salient in teachers’ career deliberations. Secondly, we found that beginning teachers express motives differentially, vary in the salience they accord the motives, and explore motives differently according to situational context. This differentiation in focus may indicate important shifting priorities and challenges as participants navigate the transition to the field. Taken together, these findings suggest that understanding and addressing identity motives in teacher development may enable more personalized and responsive tools that support teacher retention.
On the Relationship Between Bilingualism and Mathematical Performance: A Systematic Review
Authors: González-Martín Ana María , Berd-Gómez Rachid , Saura-Montesinos Victoria , Biel-Maeso Miriam , Abrahamse Elger
Published: October 2024

As part of the demands of a globalized and interconnected world, studying second languages has become a major priority. Bilingual programs implemented in recent decades have motivated an educational strategy in which content area courses are taught through L2. The potential costs of this strategy in academic performance are debated, especially in challenging areas such as mathematics. The present work systematically reviewed 71 papers based on experiments measuring mathematics performance in bilinguals in order to establish if bilinguals show a (dis)advantage in mathematics compared to monolinguals. The results of a total of 305,136 participants (57,703 bilinguals and 247,503 monolinguals) show that bilingualism does not seem to affect mathematical performance, but this is dependent on whether subjects are highly proficient bilinguals. This type of bilingual may only be affected by lower reaction times depending on the testing language. On the other hand, low language proficiency negatively impacts mathematical performance. Lastly, bilingualism enhances mathematical encoding and processes in non-language-related tasks.
MNCATM: A Multi-Layer Non-Uniform Coding-Based Adaptive Transmission Method for 360° Video
Authors: Li Xiang , Nie Junfeng , Zhang Xinmiao , Li Chengrui , Zhu Yichen , Liu Yang , Tian Kun , Guo Jia
Published: October 2024

With the rapid development of multimedia services and smart devices, 360-degree video has enhanced the user viewing experience, ushering in a new era of immersive human–computer interaction. These technologies are increasingly integrating everyday life, including gaming, education, and healthcare. However, the uneven spatiotemporal distribution of wireless resources presents significant challenges for the transmission of ultra-high-definition 360-degree video streaming. To address this issue, this paper proposes a multi-layer non-uniform coding-based adaptive transmission method for 360° video (MNCATM). This method optimizes video caching and transmission by dividing non-uniform tiles and leveraging users’ dynamic field of view (FoV) information and the multi-bitrate characteristics of video content. First, the video transmission process is formalized and modeled, and an adaptive transmission optimization framework for a non-uniform video is proposed. Based on this, the optimization problem required by the paper is summarized, and an algorithm is proposed to solve the problem. Simulation experiments demonstrate that the proposed method, MNCATM, outperforms existing transmission schemes in terms of bandwidth utilization and user quality of experience (QoE). MNCATM can effectively utilize network bandwidth, reduce latency, improve transmission efficiency, and maximize user experience quality.
Modeling Cybersecurity Risk: The Integration of Decision Theory and Pivot Pairwise Relative Criteria Importance Assessment with Scale for Cybersecurity Threat Evaluation
Authors: Šijan Aleksandar , Viduka Dejan , Ilić Luka , Predić Bratislav , Karabašević Darjan
Published: October 2024

This paper presents a comprehensive model for cyber security risk assessment using the PIPRECIA-S method within decision theory, which enables organizations to systematically identify, assess and prioritize key cyber threats. The study focuses on the evaluation of malware, ransomware, phishing and DDoS attacks, using criteria such as severity of impact, financial losses, ease of detection and prevention, impact on reputation and system recovery. This approach facilitates decision making, as it enables the flexible adaptation of the risk assessment to the specific needs of an organization. The PIPRECIA-S model has proven to be useful for identifying the most critical threats, with a special emphasis on ransomware and DDoS attacks, which represent the most significant risks to businesses. This model provides a framework for making informed and strategic decisions to reduce risk and strengthen cyber security, which are critical in a digital environment where threats become more and more sophisticated.
Reconfigurable Frequency Response Masking Multi-MAC Filters for Software Defined Radio Channelization
Authors: Arivalagan Subahar , James Britto Pari , Leung Man-Fai
Published: October 2024

Mobile technology is currently trending toward supporting multiple communication standards on a single device. This means that some reconfigurable techniques must be the foundation of their design. The two essential requirements of channel filters are minimized complexity and reconfigurability. In this research, a novel extension of Frequency Response Masking (FRM) was investigated by employing Time Division Multiplexing (TDM)-based single Multiply and Accumulate (MAC) architecture using the principle of resource sharing to realize multiple sharp filter responses from a single prototype constant group delay low pass filter. This paper uses a single multiply and add units regardless of the quantity of channels and taps. The suggested reconfigurable filter was synthesized on technology based on 0.18-µm CMOS and put into practice. Further trials were carried out on Virtex-II 2v3000ff1152-4 FPGA device. The outcomes revealed that the suggested channel filter, which was synthesized using FPGA, provides 21.36% of the area curtail and 14.88% of power scaling down on average and put into practice using ASIC provides 5.18% of the area reduction and 9.08% of power scaling down on average.
Phase-Angle-Encoded Snake Optimization Algorithm for K-Means Clustering
Authors: Xue Dan , Pang Sen-Yuan , Liu Ning , Liu Shang-Kun , Zheng Wei-Min
Published: October 2024

The rapid development of metaheuristic algorithms proves their advantages in optimization. Data clustering, as an optimization problem, faces challenges for high accuracy. The K-means algorithm is traditaaional but has low clustering accuracy. In this paper, the phase-angle-encoded snake optimization algorithm (θ-SO), based on mapping strategy, is proposed for data clustering. The disadvantages of traditional snake optimization include slow convergence speed and poor optimization accuracy. The improved θ-SO uses phase angles for boundary setting and enables efficient adjustments in the phase angle vector to accelerate convergence, while employing a Gaussian distribution strategy to enhance optimization accuracy. The optimization performance of θ-SO is evaluated by CEC2013 datasets and compared with other metaheuristic algorithms. Additionally, its clustering optimization capabilities are tested on Iris, Wine, Seeds, and CMC datasets, using the classification error rate and sum of intra-cluster distances. Experimental results show θ-SO surpasses other algorithms on over 2/3 of CEC2013 test functions, hitting a 90% high-performance mark across all clustering optimization tasks. The method proposed in this paper effectively addresses the issues of data clustering difficulty and low clustering accuracy.
Analysis of Mueller–Muller Clock and Data Recovery Circuits with a Linearized Model
Authors: Chen Junkun , Gu Youzhi , Feng Xinjie , Chi Runze , Wu Jiangfeng , Chen Yongzhen
Published: October 2024

With the development of high-speed analog-to-digital converter (ADC)-based wireline receivers, the Mueller–Muller clock and data recovery (MM-CDR) circuit has garnered increasing attention. But in the design stage, evaluating the loop performance of MM-CDR circuits in ADC-based wireline receivers is challenging due to the absence of a linearized model for a Mueller–Muller phase detector (MMPD). In this paper, a linearized model of the MMPD is proposed by analyzing the output probability of the MMPD in different transition patterns with random jitter injection, and the model is combined with an entire MM-CDR system to analyze the performance of the MM-CDR loop. Analysis of the linearized model and corresponding simulations indicate that when the reference voltage level in the MMPD is set equal to the amplitude of the average crossing voltage at the intersection of 011 and 110 patterns, the MMPD can obtain the maximum gain, which is determined by jitter, and the jitter transfer function and jitter tolerance can achieve optimum performance.
Intelligent Control Algorithms for Enhanced Frequency Stability in Single and Interconnected Power Systems
Authors: Bano Farheen , Ayaz Muhammad , Baig Dur-e-Zehra , Rizvi Syed Muhammad Hur
Published: October 2024

Ensuring stable power system performance is crucial for reliable grid operation. This study assesses various Load Frequency Control (LFC) strategies, including conventional PID, pole placement, Genetic Algorithm (GA)-optimized PID, Particle Swarm Optimization (PSO)-optimized PID, and an Artificial Neural Network (ANN)-based controller, in single and interconnected power grids. The results reveal that GA- and PSO-optimized PID outperform conventional methods, offering minimal overshoot and fast settling times. Pole placement strikes a balance between response time and stability, while the ANN controller demonstrates adaptability and quick rise times but exhibits higher overshoot and longer settling times compared to the optimization techniques. Tie-line bias control aids in frequency stabilization but presents challenges with overshoot and prolonged settling times. Notably, PSO-optimized PID emerges as a promising solution, effectively mitigating overshoot and achieving rapid frequency recovery. This study underscores the importance of tailored control strategies for optimal LFC, which are essential for enhancing power system stability and efficiency. Future research should explore the potential of advanced techniques, such as deep learning and reinforcement learning, to further improve control performance.
Dynamic Simulation of Carbon Emission Peak in City-Scale Building Sector: A Life-Cycle Approach Based on LEAP-SD Model
Authors: Du Yawei , Liu Hongjiang , Du Tiantian , Liu Junyue , Yin Ling , Yang Yang
Published: October 2024

Systematically predicting carbon emissions in the building sector is crucial for formulating effective policies and plans. However, the timing and potential peak emissions from urban buildings remain unclear. This research integrates socio-economic, urban planning, building technology, and energy consumption factors to develop a LEAP-SD model using Shenzhen as a case study. The model considers the interrelationship between socio-economic development and energy consumption, providing more realistic scenario simulations to predict changes in carbon emissions within the urban building sector. The study investigates potential emission peaks and peak times of buildings under different population and building area development scenarios. The results indicate that achieving carbon peaking by 2030 is challenging under a business as usual (BAU) scenario. However, a 10% greater reduction in energy intensity compared to BAU could result in peaking around 2030. The simulation analysis highlights the significant impact of factors such as population growth rate, per capita residential building area, and energy consumption per unit building area and the need for a comprehensive analysis. It provides more realistic scenario simulations that not only enhance theories and models for predicting carbon emissions but also offer valuable insights for policymakers in establishing effective reduction targets and strategies.
Liquid Water Transport and Distribution in the Gas Diffusion Layer of a Proton Exchange Membrane Fuel Cell Considering Interfacial Cracks
Authors: Li Bao , Cao Shibo , Qin Yanzhou , Liu Xin , Xu Xiaomin , Xin Qianfan
Published: October 2024

The proton exchange membrane fuel cell (PEMFC), with a high energy conversion efficiency, has become an important means of hydrogen energy utilization. However, water condensation is unavoidable in the PEMFC because of low operating temperatures. The impact of liquid water on PEMFC performance and stability is significant. The gas diffusion layer (GDL) provides a critical transport path for liquid water in the PEMFC. Liquid water saturation and distribution in the GDL determine water flooding and mass transfer efficiency in the PEMFC. In this study, focusing on the effects of the water introduction method, osmotic pressure, and contact angle, the liquid water transport in the GDL was numerically investigated based on a pore-scale model using the volume of fluid (VOF) method. The results showed that compared with the conventional water introduction method without cracks, the saturation and spatial distribution of water inside the GDL obtained in the simulation were more consistent with the experimental results when the water was introduced through the microporous layer (MPL) crack. It was found that increasing the osmotic pressure resulted in a faster rate of water penetration, faster approaching the steady-state performance, and higher saturation. The ultra-high osmotic pressure contributed to the secondary breakthrough with a significant increase in saturation. Increasing the contact angle caused higher capillary resistance, especially in the region with small pore sizes. At a constant osmotic pressure, as the contact angle increased, the liquid water gradually failed to penetrate into the small pores around the transport path, causing saturation reduction and an ultimate failure to break through the GDL. Increasing the contact angle contributed to a higher breakthrough pressure and secondary breakthrough pressure.
Optimal Configuration Model for Large Capacity Synchronous Condenser Considering Transient Voltage Stability in Multiple UHV DC Receiving End Grids
Authors: Zhao Lang , Wang Zhidong , Sheng Hao , Li Yizheng , Wang Xueying , Wang Yao , Yu Haifeng
Published: October 2024

In a multi-fed DC environment, the UHV DC recipient grid faces significant challenges related to DC phase shift failure and voltage instability due to the high AC/DC coupling strength and low system inertia level. While the new large-capacity synchronous condensers (SCs) can provide effective transient reactive power support, the associated investment and operation costs are high. Therefore, it is valuable to investigate the optimization of SC configuration at key nodes in the recipient grid in a scientific and rational manner. This study begins by qualitatively and quantitatively analyzing the dynamic characteristics of DC reactive power and induction motors under AC faults. The sub-transient and transient reactive power output model is established to describe the SC output characteristics, elucidating the coupling relationship between the SC’s reactive power output and the DC reactive power demand at different time scales. Subsequently, a critical stabilized voltage index for dynamic loads is defined, and the SC’s reactive power compensation target is quantitatively calculated across different time scales, revealing the impact of transient changes in DC reactive power on the transient voltage stability of the multi-fed DC environment with dynamic load integration. Finally, an optimal configuration model for the large-capacity SC is proposed under the critical stability constraint of dynamic loads to maximize the SC’s reactive power support capability at the lowest economic cost. The proposed model is validated in a multi-fed DC area, demonstrating that the optimal configuration scheme effectively addresses issues related to DC phase shift failures and voltage instability resulting from AC bus voltage drops.
Impact of Carbon Tax on Renewable Energy Development and Environmental–Economic Synergies
Authors: Feng Keying , Yang Zeyu , Zhuo Yu , Jiao Lili , Wang Bowen , Liu Zhi
Published: October 2024

Global warming caused by greenhouse gas emissions has become a worldwide environmental problem, posing a great threat to human survival. As the world’s largest emitter of carbon dioxide, China has pledged to reach peak carbon emissions by no later than 2030 and carbon neutrality by 2060. It is found that a carbon tax is a powerful incentive to reduce carbon emissions and promote an energy revolution, but it may have negative socio-economic impacts. Therefore, based on China’s 2020 input–output table, this paper systematically investigates the impacts of a carbon tax on China’s economy, carbon emissions, and energy by applying a computable general equilibrium model to determine the ideal equilibrium between socio-economic and environmental objectives. Based on energy use characteristics, we subdivided the energy sector into five major sectors: coal, oil, natural gas, thermal power generation, and clean power. The results show that when the carbon emission reduction target is less than 15%, that is, when the equilibrium carbon tax price is less than 54 yuan/ton, the implementation of a carbon tax policy can significantly reduce carbon emission and fossil fuel energy consumption, while only slightly reducing economic growth rate, and can achieve the double dividend of environment and economy. Moreover, because the reduction of coal consumption has the greatest impact on reducing carbon emissions, the ad valorem tax rate on coal after the carbon tax is imposed is the highest because coal has the highest carbon emission coefficient among fossil fuels. In addition, as an emerging clean energy source, hydrogen energy is the ideal energy storage medium for achieving clean power generation in power systems. If hydrogen energy can be vigorously developed, it is expected to greatly accelerate the deep decarbonization of power, industry, transportation, construction, and other fields.
A Novel Wind Energy Gathering Structure for the Savonius Wind Turbine and Its Parameter Optimization Based on Taguchi’s Method
Authors: Zhang Tianjiao , Xu Shuhui
Published: October 2024

An auxiliary structure can significantly improve the wind-trapping capacity of the Savonius wind turbine. In this study, a novel auxiliary structure called a wind energy gathering structure (WEGS) is proposed, and its five parameters, namely the lengths of the shrinkage and diffusion tubes, the length of the centerboard, the length of the throat, the length of the wind board, and the shrinkage and diffusion angles, are investigated using computational fluid dynamics (CFD) and Taguchi’s method. Meanwhile, Taguchi’s method and ANOVA reveal that among the studied parameters, the shrinkage and diffusion angles, the length of the centerboard, and the lengths of the shrinkage and diffusion tubes have a more significant influence on the performance of the WEGS. At a tip speed ratio (TSR) value of 1 and a wind speed of 7 m/s, the optimized combination of the WEGS parameters obtained by Taguchi’s method improves the mean torque coefficient of the turbine by 42.1%. Moreover, at other TSRs (0.6–1.2), the turbine with the WEGS also outperforms an open turbine in terms of aerodynamic (increases of 20.1–53%) and lifetime performance.
Control Structures for Combined H2/Electricity from Offshore Wind Turbines
Authors: Monroy-Morales José Luis , Peña-Alzola Rafael , Campos-Gaona David , Anaya-Lara Olimpo
Published: October 2024

Wind energy proves to be a highly favourable choice for electricity generation due to its clean and renewable nature, and is playing a significant role in reducing global greenhouse gas emissions. Offshore wind turbine systems have gained widespread popularity as they can capitalise on elevated and consistent wind speeds surpassing those found in onshore locations, resulting in increased energy efficiency. Furthermore, offshore wind power possesses the potential to emerge as a significant electricity source for the production of green hydrogen. As water electrolysis technology for hydrogen production continues to advance, utilizing offshore wind power for hydrogen generation is becoming more economically viable and practical. Offshore wind power with higher wind speeds in combination with efficient control structures presents an attractive option for electricity generation and hydrogen co-production. This paper aims to present and evaluate four different production structures for combined H2/energy generation from offshore wind turbines. Previous research studies in this area often overlook control structures and lack information on power converter operations. In contrast, this article studies control structures that enable proper functionality and ensure adequate interoperability, enhancing the reliability of renewable energy integration. Each structure, including both wind turbines and electrolyser, is described in detail, along with the corresponding controllers. Simulation results are presented for each structure and controller to demonstrate their effective operation.
Enhancing Performance of Composite-Based Triboelectric Nanogenerators Through Laser Surface Patterning and Graphite Coating for Sustainable Energy Solutions
Authors: Amorntep Narong , Siritaratiwat Apirat , Srichan Chavis , Sriphan Saichon , Wiangwiset Thalerngsak , Ariyarit Atthaporn , Supasai Wisut , Bootthanu Nuttapong , Narkglom Sorawit , Vittayakorn Naratip , Surawanitkun Chayada
Published: October 2024

The performance of composite-based triboelectric nanogenerators (C–TENGs) was significantly enhanced through laser surface patterning and graphite coating. The laser etching process produced accurate and consistent patterns, increasing surface area and improving charge accumulation. SEM imagery confirmed the structural differences and enhanced surface properties of the laser-etched C–TENGs. Graphite fibers further augmented the contact surface area, enhancing charge accumulation and diffusion. Experimental results demonstrated that the optimized C–TENGs, especially those with line patterns and graphite coating, achieved a maximal 98.87 V open-circuit voltage (VOC) and a 0.10 µA/cm2 short-circuit current density (JSC) under a 20 N external force. Environmental tests revealed a slight decrease in performance with increased humidity, while long-term stability tests indicated consistent performance over three weeks. Practical application tests showed the potential of C–TENGs integrated into wearable devices, generating sufficient energy for low-power applications, thereby highlighting the promise of these devices for sustainable energy solutions.
Greenhouse Gas Emission Estimation Using Extended Input–Output Tables for Thailand’s Biomass Pellet Industry
Authors: Buasan Prangvalai , Sajjakulnukit Boonrod , Bowonthumrongchai Thongchart , Gheewala Shabbir H.
Published: October 2024

Greenhouse gas (GHG) emissions from Thailand’s biomass pellet production were comprehensively assessed, with a specific focus on wood and corn pellets. Employing the extended input and output tables, the anticipated economic and environmental effects of the rising demand for biomass pellets within the Asia–Pacific Economic Cooperation region, which is projected to see an increase exceeding 33% by the year 2050, were investigated. The estimations of CO2, CH4, and N2O emissions, which were conducted utilizing an open Leontief model based on the 2015 National Input–Output Tables, covered each stage of the production process. The results show that emissions from the production of corn pellets are expected to rise steadily, from 52.91 MtCO2e in 2022 to 75.77 MtCO2e by 2030, whereas emissions from wood pellet production are set to increase more substantially, from 210.30 to 301.18 MtCO2e within the same timeframe. Data derived from surveys and interviews with corn farmers and wood pellet manufacturers informed the lifecycle data for the biomass pellet supply chain from cradle to gate. The findings suggest that Thailand’s power sector could benefit significantly from the biomass potential in the northern part of Thailand, which boasts an estimated energy content of corncob at 39 ktoe (0.0016 TJ). Market demand scenarios were explored in two forms: one where it was assumed that all biomass pellets are to be exported to Japan and South Korea, expecting a combined demand of approximately 560,262 tons by 2030, and another positing that 10% of production will be reserved for the domestic market, with a forecasted annual increase of 10% from 2020 to 2050. This paper highlights the need to prioritize low-emission renewable energy sources, expand technologies with lower lifecycle emissions, optimize the biomass supply chain to enhance efficiency, and introduce sustainable energy practices. The detailed GHG emissions analysis provides critical insights for policy formulation, underscoring the importance of sustainable transitions in the context of increasing biomass demand.
Modeling and Analyzing of CMOS Cross-Coupled Differential-Drive Rectifier for Ultra-Low-Power Ambient RF Energy Harvesting
Authors: Zheng Liming , Wang Hongyi , Wu Jianfei , Liu Peiguo , Li Runze
Published: October 2024

This paper models and analyzes the Complementary Metal Oxide Semiconductor (CMOS) cross-coupled differential-drive (CCDD) rectifier for Ultra-Low-Power ambient radio-frequency energy harvesters (RFEHs) working in the subthreshold region. In this paper, two closed-form equations of CCDD rectifier output voltage and input resistance in the subthreshold region were derived based on BSIM4 models of NMOS and PMOS. The model give insight to specify circuit parameters according to different inputs, transistor sizes, threshold voltages, numbers of stages, load conditions and compensation voltages, which can be used to optimize the rectifier circuit. There is a good agreement between the simulation results and these models, and these models have a maximum deviation of 10% in comparison with the simulation results in the subthreshold region. The measurement results of a single-stage CCDD rectifier reported in a previous paper were adopted to verify the model. The output voltage and input resistance predicted by these models provide excellent consistency with corresponding measurement results. The model can be employed to optimize the CCDD rectifier without expensive calculation in the design stage.
Study on Winding Inductances in Stator Surface-Mounted Permanent Magnet Machines
Authors: Zhu Xiaofeng , Yue Yan
Published: October 2024

Winding inductance always plays a key role in the electromagnetic performances of stator surface-mounted permanent magnet (SSPM) machines, including their flux-weakening capability, prospective fault current, power factor, current ripple, etc. Generally speaking, winding inductance mainly comprises three components: an air-gap component, a slot-leakage component, and an end-leakage component. In this paper, firstly, the winding pole pairs of SSPM machines are investigated based on the magneto-motive force-permeance model, through which the winding configurations can also be determined. Then, according to the winding configurations, three analytical expressions for each inductance component are derived to evaluate the winding inductance per phase. In addition, finite element analysis (FEA) is employed to verify the effectiveness of the derived analytical expressions. Meanwhile, three prototyped SSPM machines are manufactured, and their winding inductances are measured to further verify the analytical expressions. The measured results agree with both the analytical and FEA results very well.
The Impact of Post-Furnace Steel Processing Equipment on Reducing Voltage Fluctuations Caused by Arc Furnaces
Authors: Olczykowski Zbigniew
Published: October 2024

Arc devices are among the receivers with the highest power connected to power systems. Due to dynamic load changes, these receivers generate a number of disturbances that affect the quality of electric power. The most important disturbances include voltage fluctuations. It is also worth mentioning the asymmetry and deformation of the supply voltage curve. This article discusses the mutual interaction of receivers operating in parallel, operating stably, and devices with dynamic current consumption. Calculations based on model tests and the results of parameters characterizing the quality of energy, which were recorded in the line supplying the steelworks, are presented. The power supply conditions (power of the short-circuit network) were assessed to influence the degree of suppression of voltage fluctuations by loads with stable current consumption.
Framework for Implementation of Building Automation Control Programs for Industrial Heating and Cooling Systems
Authors: Frank  Michael , Borst  Fabian , Theisinger  Lukas , Lademann  Tobias , Fuhrländer-Völker  Daniel , Weigold  Matthias
Published: October 2024

This article proposes a novel framework for the rapid implementation of automation programs in industrial heating and cooling systems. The global push for sustainability necessitates significant infrastructural transformations within these systems, which currently rely heavily on fossil fuels and are responsible for 75% of industrial final energy consumption. Our research highlights the critical role of design patterns and object-oriented programming principles to address the complex integration of additional energy converters and storage into automation programs. By leveraging design patterns, our framework encapsulates the intricacies of various components, such as actuators, sensors, and storage, within a comprehensive object-oriented model that also allows the integration of different control strategies. Qualitatively, this approach enhances the reusability, scalability, and adaptability of automation programs. Therefore, quantitatively, our framework enables a more resilient and efficient energy system. The framework is validated through its application to a complex, cross-linked industrial heating and cooling system at the ETA Research Factory of the Technical University of Darmstadt. Using the developed framework reduces implementation effort significantly due to its consistent and modular structure resulting from the reusable design patterns.
Diffusion of N2/CH4/CO2 in Heptane-Containing Nanoblind Ends
Authors: Wang Yiran , Chen Xinglong , Liu Nannan , Qi Hengchen
Published: October 2024

The prevalence of micropores and nanopores in low-permeability reservoirs is a cause for concern, as it results in a sizeable quantity of oil reserves being trapped within them. The water-gas dispersion system has the capacity to expand the reservoirs’ wave volume and enhance oil recovery. While the microscopic oil repulsion mechanism has been the center of attention, the oil repulsion effect of three distinct types of gases (N2, CH4, and CO2) is of particular importance in understanding the displacement mechanism of N2/CH4/CO2 on heptane at the blind end of the nanometer. A molecular dynamics simulation using the LAMMPS software was employed to construct a model of a blind end of heptane on a SiO2 wall and an interface model with different types of gas molecules. This was done to investigate the microscopic mechanism of heptane replacement by gas molecules. The temperature (50 °C) and pressure (30 MPa) of the reservoir in the Changqing oil field are selected as the parameters for analysis. The findings indicate that all three types of gas molecules can enter the blind end and displace heptane. However, supercritical CO2 forms a mixed phase with heptane, which is more prone to extruding oil molecules situated near the inner wall surface of the blind end and desorbing the oil film. The results demonstrate that, in the context of the blind end, gaseous CO2 exhibits a lower solvation ability but superior extrusion diffusion ability for heptane compared to N2 and CH4. Furthermore, the interaction energy indicates that the interactions between two states of CO2 and heptane, as well as the thickness of the interface, increase with increasing pressure and temperature. The findings of this study elucidate the microscopic mechanism underlying the replacement of oil droplets or oil films at the blind end by different gases under reservoir conditions at the molecular level and offer further guidance for the selection of the gas phase and the replacement state in the water-gas dispersive drive system.
Study of Contactless Computer Vision-Based Road Condition Estimation Methods Within the Framework of an Operational Design Domain Monitoring System
Authors: Subramanian Ramakrishnan , Büker Ulrich
Published: October 2024

Deployment of Level 3 and Level 4 autonomous vehicles (AVs) in urban environments is significantly constrained by adverse weather conditions, limiting their operation to clear weather due to safety concerns. Ensuring that AVs remain within their designated Operational Design Domain (ODD) is a formidable challenge, making boundary monitoring strategies essential for safe navigation. This study explores the critical role of an ODD monitoring system (OMS) in addressing these challenges. It reviews various methodologies for designing an OMS and presents a comprehensive visualization framework incorporating trigger points for ODD exits. These trigger points serve as essential references for effective OMS design. The study also delves into a specific use case concerning ODD exits: the reduction in road friction due to adverse weather conditions. It emphasizes the importance of contactless computer vision-based methods for road condition estimation (RCE), particularly using vision sensors such as cameras. The study details a timeline of methods involving classical machine learning and deep learning feature extraction techniques, identifying contemporary challenges such as class imbalance, lack of comprehensive datasets, annotation methods, and the scarcity of generalization techniques. Furthermore, it provides a factual comparison of two state-of-the-art RCE datasets. In essence, the study aims to address and explore ODD exits due to weather-induced road conditions, decoding the practical solutions and directions for future research in the realm of AVs.
Evaluating Indoor Air Quality in Residential Environments: A Study of PM2.5 and CO2 Dynamics Using Low-Cost Sensors
Authors: Shah Kabir Bahadur , Kim Dylan , Pinakana Sai Deepak , Hobosyan Mkhitar , Montes Armando , Raysoni Amit U.
Published: October 2024

Indoor air quality (IAQ) poses a significant public health concern, and exposures to high levels of fine particulate matter (PM2.5) and carbon dioxide (CO2) could have detrimental health impacts. This study focused on assessing the indoor air pollutants in a residential house located in the town of Mission, Hidalgo County, South Texas, USA. The PM2.5 and CO2 were monitored indoors: the kitchen and the bedroom. This investigation also aimed to elucidate the effects of household activities such as cooking and human occupancy on these pollutants. Low-cost sensors (LCSs) from TSI AirAssure™ were used in this study. They were deployed within the breathing zone at approximately 1.5 m above the ground. Calibration of the low-cost sensors against Federal Equivalent Method (FEM) instruments was undertaken using a multiple linear regression method (MLR) model to improve the data accuracy. The indoor PM2.5 levels were significantly influenced by cooking activities, with the peak PM2.5 concentrations reaching up to 118.45 μg/m3. The CO2 levels in the bedroom increased during the occupant’s sleeping period, reaching as high as 1149.73 ppm. The health risk assessment was assessed through toxicity potential (TP) calculations for the PM2.5 concentrations. TP values of 0.21 and 0.20 were obtained in the kitchen and bedroom, respectively. The TP values were below the health hazard threshold (i.e., TP < 1). These low TP values could be attributed to the use of electric stoves and efficient ventilation systems. This research highlights the effectiveness of low-cost sensors for continuous IAQ monitoring and helps promote better awareness of and necessary interventions for salubrious indoor microenvironments.
Development and Characterization of Thermal Protection Gels for Steel Pipelines Transporting Combustible Materials
Authors: Li Jing , Gong Jianhua , Shen Jun , Yang Kege , Tan Longhua , Li Haoyuan , Zhao Jinlong
Published: October 2024

Due to low costs, pipelines are commonly used for transporting hazardous substances such as combustible liquids and gasses. Currently, chemical industrial parks and gas production stations have dense pipeline networks. In the case of a pipeline leakage and subsequent fire accident, the adjacent pipelines could be directly impinged by the flame or engulfed in hot smoke, with the potential to result in a chain of accidents and catastrophic consequences. It is thus of practical importance to develop an efficient thermal protection material for pipelines. In this study, a new type of bio-based gel material was prepared for pipeline thermal protection, using guar gum (GG) as the gelling agent, sodium tetraborate (B) as the crosslinking agent and magnesium chloride (MgCl2) as the fire retardant. Firstly, orthogonal experiments were conducted to examine the gelling time of the gel and determine the optimal formulations that meet the protection requirements. Subsequently, water retention, thermal stability and the microstructure of these formulations were analyzed. Finally, the thermal protection performance of the gel formulations was evaluated under the direct impingement of flames or high-temperature smoke. The results indicated that the best performance was achieved by the formulation with GG, B and MgCl2 mass fractions of 2.5, 0.6 and 0.5 wt%, respectively. This formulation also exhibited the best water retention capacity and thermal stability. In the pipeline thermal protection experiments, this formulation achieved effective protection times of 216 s (for a 90 mm diameter) and 312 s (for a 120 mm diameter) for the lower part of the pipeline under direct flame impingement. Under high-temperature smoke impingement, this formulation also showed excellent performance. These research and findings can provide an important foundation for the further development of thermal protection materials for pipelines under fire conditions.
Impact of Fire Recurrence and Water Stress on the Root Nucleolar Activity of Maritime Pine (Pinus pinaster Ait.) Individuals Whose Seeds Were Harvested in Post-Fire Naturally Regenerated Stands
Authors: Carvalho Ana , Lopes Inês Margarida , Ribeiro Stéphanie , Fonseca Teresa , Lima-Brito José
Published: October 2024

The main role of the nucleolus is ribosomal biogenesis, but it also responds to stress with changes in number, area, and/or morphology. Nucleoli with transcriptionally active ribosomal RNA genes are selectively stained by silver nitrate. Hypothesising that fire recurrence and/or polyethylene glycol (PEG)-induced water stress would cause nucleolar changes in Pinus pinaster roots, nucleolar parameters were analysed upon the germination of seeds harvested in post-fire naturally regenerated stands with different fire regimes. An unburned stand was used as a control. The nucleoli number varied from 1 to 15 among stands and PEG treatments, but a mode of five or six nucleoli was found. The number of nucleoli per interphase (N) increased (p < 0.001) with fire recurrence (stand effect). Increasing PEG concentration (treatment effect) decreased the nucleoli number, notably in the stand with the highest fire recurrence. The nucleolar area decreased (p < 0.001) with increased nucleoli number, fire recurrence, and/or PEG concentration. Fire recurrence and water scarcity are forecasted for future climate scenarios. As demonstrated earlier, these factors could influence protein synthesis or the cell cycle’s regularity, which are crucial processes for root growth and pine seedling establishment. Furthermore, this work revealed that nucleolar parameters could be suitable biomarkers for pine stress studies.
Impact of Ferulated Arabinoxylans from Maize Bran on Farinograph and Pasting Properties of Wheat Flour Blends
Authors: Hussain Muzzamal , Simsek Senay
Published: October 2024

This research explores the extraction of ferulated arabinoxylans (FAXs) from maize bran and their incorporation into wheat flour to assess their impact on rheological and pasting properties. Flour blends were prepared with FAX concentrations of 0%, 2%, 4%, 6%, 8%, and 10%, and these blends were then evaluated using farinograph, mixograph, micro-extensibility, and viscosity analyses. The results indicated that farinograph water absorption increased significantly (p ≤ 0.05), ranging from 54.9% to 60.5%, as the FAX content rose, correlating with higher gel-forming potential. Notably, the 2% FAX treatment (FAX2) exhibited the longest dough development time at 24.7 min. Stability and mixing time index (MTI) values also varied significantly (p ≤ 0.05) among treatments, with FAX2 displaying a longer mixing time of 14.4 ± 3.3 min. A pasting analysis revealed a significant decrease in peak and hot paste viscosity (p < 0.05) with increasing FAX concentrations, suggesting an association between lower hot paste viscosity and reduced breakdown. Micro-extensibility measures further indicated that blends with 0% and 2% FAX had greater extensibility, while the 4% FAX blend showed higher resistance. Overall, this research aims to advance the understanding of how these components can enhance flour functionality and contribute to the development of healthier, higher-quality baked products.
Effects of Prickly Ash Seed Dietary Supplementation on Meat Quality, Antioxidative Capability, and Metabolite Characteristics of Hu Lambs
Authors: Li Qiao , Wu Yi , Qi Xingcai , Liu Zilong , Wang Chunhui , Ma Xueyi , Ma Youji
Published: October 2024

In China, the processing of prickly ash (PA) produces a large number of by-products, including prickly ash seeds (PASs), which are rich in bioactive components such as flavonoids and phenolic compounds, and which may have an important influence on meat quality and muscle metabolites. Therefore, this study aimed to assess the impact of dietary PAS supplementation on the meat quality, antioxidant activity, and metabolite characteristics of lambs. Eighteen 3-month-old Hu lambs (25.66 ± 3.03 kg body weight) were randomly allotted to three different dietary treatment groups. In the three dietary treatments, 0% (basal diet, CON), 3% (CON with 3% PAS, low-dose PAS, and LPS), and 6% (CON with 6% PAS, high-dose PAS, and HPS) PASs were used. Results indicated significant improvements in the HPS group, including reduced cooking loss and increased fat content. The L* and b* 45 min values were significantly lower in the PAS groups than those in the CON group (p < 0.05). Additionally, dietary PAS supplementation increased in MUFA, PUFA, n-3 PUFA, PUFA/MUFA ratio, NEAA, and FFA compared to the CON group. Furthermore, PAS supplementation significantly improved serum and muscle antioxidant capacity. Metabolomic analyses revealed that increased metabolites, such as tryptophan, leucine, citric acid, adenosine 5′-triphosphate, creatine phosphate, inosine, and α-ketoglutaric acid, were primarily enriched in the biosynthesis of cofactors and nucleotide and purine metabolism pathways. Notably, supplementation with 6% of PASs exhibited the most prominent effect on lamb meat quality in this study. Therefore, the application of PASs as a feed component in lamb production can not only improve meat quality and muscle antioxidant capacity but also save feed costs.
Coconut Testa Flour Sub-Fractions: Correlation Between FTIR Spectral Data and α-Glucosidase Inhibitory Activities
Authors: Gunarathne Rasika , Ulpathakumbura Savani , Marikkar Nazrim , Jayasinghe Lalith , Lu Jun
Published: October 2024

Fourier-transform infrared spectroscopy (FTIR) serves as a rapid analytical technique to characterize food specimens chemically. The purpose of this study was to investigate the potential of FTIR combined with multivariate statistics to detect Alpha-glucosidase (Alpha-glu) inhibitory activities of a non-cereal flour-like coconut testa flour (CTF). CTF of five distinct local cultivars was sequentially extracted with hexane, ethyl acetate (EtOAc), and methanol (MeOH) to assay the Alpha-glu inhibitory activity. FTIR spectra of CTF extracts were obtained within the range of 4000–500 cm−1 and the prominent spectral peaks obtained for both hexane and EtOAc extracts were roughly similar but some additional peaks were observed in EtOAc extracts representing phenolic constituents. The major absorbance peaks found in MeOH extracts were primarily indicative of the occurrence of the hydroxyl group associated with carbohydrates and phenolic compounds. The multivariate predictive models developed using partial least squares (PLS) and orthogonal partial least squares (OPLS) regression analyses indicated a strong correlation between Alpha-glu inhibitory activity and spectral data. Models developed for the spectral regions 3700–2800 cm−1 and 1800–500 cm−1 exerted the highest regression coefficients with the lowest root mean square errors. In OPLS regression analysis, the model obtained with third-derivative spectral data was identified as the best, exhibiting the highest regression coefficients and the lowest root mean square errors. Both PLS and OPLS regression analyses indicated a potential correlation of Alpha-glu inhibitory activity with FTIR spectral regions. Notably, OPLS models offered enhanced interpretability of the model parameters. This study suggests that the application of multivariate regression analysis of FTIR spectral data on coconut-based products could help to detect Alpha-glu inhibitory activities.