bluuebunny/crossref_metadata_2025 huggingface dataset:
Scratch Response of Hollow Cathode Radiofrequency Plasma-Nitrided and Sintered 316L Austenitic Stainless Steel
Authors: Broch Marcelo , Fontoura Cristian Padilha , Lima Arnaldo Oliveira , Ordoñez Michell Felipe Cano , Machado Izabel Fernanda , Aguzzoli Cesar , Farias María Cristina Moré
Published: March 2024

Low-temperature plasma nitriding is a thermochemical surface treatment that promotes surface hardening and wear resistance enhancement without compromising the corrosion resistance of sintered austenitic stainless steels. Hollow cathode radiofrequency (RF) plasma nitriding was conducted to evaluate the influence of the working pressure and nitriding time on the microstructure and thickness of the nitrided layers. A group of samples of sintered 316L austenitic stainless steel were plasma-nitrided at 400 °C for 4 h, varying the working pressure from 160 to 25 Pa, and the other group was treated at the same temperature, varying the nitriding time (2 h and 4 h) while keeping the pressure at 25 Pa. A higher pressure resulted in a thinner, non-homogeneous nitrided layer with an edge effect. Regardless of the nitriding duration, the lowest pressure (25 Pa) promoted the formation of a homogenously nitrided layer composed of nitrogen-expanded austenite that was free of iron or chromium nitride and harder and more scratching-wear-resistant than the soft steel substrate.
Fabrication of Thin TEG (Bi-Ni) Using Magnetron Sputtering Technology and Investigations
Authors: Kavaliauskas Žydrūnas , Baltušnikas Arūnas , Milieška Mindaugas , Valinčius Vitas
Published: March 2024

As the industry develops more and more, heat is produced during fabrication processes, resulting in an excess of heat. One of the ways to solve the problem can be the conversion of excess heat into electricity using a thermoelectric generator (TEG). The authors of this paper propose a method of using thin-film TEGs for electricity generation, a procedure that has been given little attention to in the literature. In this study, thin TEGs (about 50–100 nm thick) were obtained from Bi-Ni, using magnetron sputtering technology. This type of TEG can be used not only as a device that generates electricity, but also as a protective layer for various systems, protecting them from environmental influences. In addition, such TEGs can be formed on a complex, uneven surface, with various details changing their geometric shape. As shown from XRD studies, the obtained Bi-Ni layer is polycrystalline. XRD studies help to determine whether the layer obtained is composed of pure layers of Bi and Ni metals or whether metal oxides have formed (metal oxides have a negative effect on electrical conductivity). An increase in the temperature from 80 to 120 K, respectively, increases the voltage generated by the TEG from 0.01 to 0.03 V. Meanwhile, the efficiency of such TEG element changes from 1 to 4.5% when the temperature change increases from 30 to 119 K.
Comparison of the Cathodic Protection of Epoxy Resin Coating/Zinc-Rich Coatings on Defective Areas under Atmospheric and Immersion Conditions: The Secondary Activation of Zinc Particles
Authors: Zhang Wei , Xia Wenting , Chen Zhiwei , Zhang Guoqing , Qian Sicheng , Lin Zhifeng
Published: March 2024

The cathodic protection provided by epoxy coating/epoxy zinc-rich coatings on defective areas under atmospheric and immersion conditions was studied via a Q235 wire beam electrode (WBE), scanning electron microscopy, X-ray diffraction, and surface morphology analysis. The results showed that the cathodic protection processes under the two test conditions displayed significant differences. The effective protection time of the defective area under the atmospheric condition was 1.7 times that under the immersion condition. Compared with the immersion condition, zinc particles in zinc-rich coatings under the atmospheric condition exhibited higher cathodic protection efficiency. The possible activation mechanism of zinc particles under the two conditions was elucidated.
What Are the Factors That Enable Thread Lifting to Last Longer?
Authors: Hong Gi-Woong , Hu Hyewon , Park Soo-Yeon , Wan Jovian , Yi Kyu-Ho
Published: March 2024

Thread-lifting traditionally addressed aging-related skin laxity by leveraging precise thread placement and traction. However, recent advancements, notably cog threads, expanded its application to younger patients seeking facial contour refinement. These newer threads effectively lift sagging areas and refine facial contours, broadening the procedure’s appeal. Challenges arise in selecting threads due to variable physician preferences and patient needs. Clear indications for thread efficacy are vital for credibility and tailored selection. Thread choice depends on tissue laxity, necessitating lighter threads for minimal laxity and stronger ones for significant sagging. However, no single thread universally suits all cases. Combining different threads is favored for optimal outcomes and minimizing side effects. Excessive traction post-procedure may lead to prolonged discomfort and skin irregularities. Post-procedural tension adjustments through massage remain debated, potentially conflicting with minimally invasive principles. Understanding thread characteristics guides tailored selection, considering patient conditions and procedural goals. This comprehensive understanding extends beyond specific products, aiming for optimal outcomes in thread-lifting procedures. Key factors influencing outcomes encompass thread materials, thickness, cog shapes, insertion depth, lifting vectors, and absorbable thread expiration dates.
Molecular Dynamics Study of Friction between Ag Nanoparticle and Two-Dimensional Titanium Carbide Ti2C (MXene)
Authors: Borysiuk Vadym , Lyashenko Iakov A. , Popov Valentin L.
Published: March 2024

We report the results of atomistic simulations of friction between two-dimensional titanium carbide Ti2C (MXene) and a silver nanoparticle located on its surface. Numerical experiments were performed within classical molecular dynamics methods using a previously developed scheme for simulations of interactions between MXenes and metal nanoparticles. In the computer experiments performed, both tangential and shear forces were applied to the Ag nanoparticle to initiate its sliding on the surface of the Ti2C MXene. During the simulations, the nanotribological parameters of the studied system, such as the friction force, contact area, friction coefficient, and tangential shear, were computed. It is shown that, for the studied system, the friction coefficient does not depend on the velocity of nanoparticle movement or the contact area. Additionally, the sliding friction of the nanoparticle on the flexible substrate was considered. The latter case is characterized by a larger friction coefficient and contact area due to the formation of wrinkles on the surface of the substrate.
Overview of the Engagement Process to Develop the Future of Cancer Impact (FOCI) Report in Alberta: The Power of Collective Action
Authors: Pujadas Botey Anna , Bond Tara R. , Farah Eliya , Carbonell Chantelle , Dyck Stacey , Estey Angela , Stewart Douglas A. , Brenner Darren R. , Robson Paula J.
Published: March 2024

This commentary provides a detailed overview of the extensive stakeholder engagement efforts critical to the development of the Future of Cancer Impact (FOCI) in Alberta report. The overarching aim of the FOCI report was to support informed and strategic discussions and actions that will help key stakeholders in the province prepare for a future with increasing cancer incidence and survival. Employing a comprehensive approach and a diverse range of engagement activities, insights from a wide spectrum of stakeholders were gathered and subsequently used to shape the content of the report. This inclusive process ensured broad representation of perspectives, contributing to a deeper understanding of the complexities in cancer care. The outcome is a robust, consensus-driven report with recommendations set to drive significant transformations within the healthcare system. These efforts highlight the critical role of extensive, inclusive, and collaborative engagement in shaping healthcare initiatives and advancing discussions crucial for the future of cancer care in Alberta.
AI-Assisted X-ray Fracture Detection in Residency Training: Evaluation in Pediatric and Adult Trauma Patients
Authors: Meetschen Mathias , Salhöfer Luca , Beck Nikolas , Kroll Lennard , Ziegenfuß Christoph David , Schaarschmidt Benedikt Michael , Forsting Michael , Mizan Shamoun , Umutlu Lale , Hosch René , Nensa Felix , Haubold Johannes
Published: March 2024

Background: This study aimed to evaluate the impact of an AI-assisted fracture detection program on radiology residents’ performance in pediatric and adult trauma patients and assess its implications for residency training. Methods: This study, conducted retrospectively, included 200 radiographs from participants aged 1 to 95 years (mean age: 40.7 ± 24.5 years), encompassing various body regions. Among these, 50% (100/200) displayed at least one fracture, totaling one hundred thirty-five fractures, assessed by four radiology residents with different experience levels. A machine learning algorithm was employed for fracture detection, and the ground truth was established by consensus among two experienced senior radiologists. Fracture detection accuracy, reporting time, and confidence were evaluated with and without AI support. Results: Radiology residents’ sensitivity for fracture detection improved significantly with AI support (58% without AI vs. 77% with AI, p < 0.001), while specificity showed minor improvements (77% without AI vs. 79% with AI, p = 0.0653). AI stand-alone performance achieved a sensitivity of 93% with a specificity of 77%. AI support for fracture detection significantly reduced interpretation time for radiology residents by an average of approximately 2.6 s (p = 0.0156) and increased resident confidence in the findings (p = 0.0013). Conclusion: AI support significantly enhanced fracture detection sensitivity among radiology residents, particularly benefiting less experienced radiologists. It does not compromise specificity and reduces interpretation time, contributing to improved efficiency. This study underscores AI’s potential in radiology, emphasizing its role in training and interpretation improvement.
A Collaborative Platform for Advancing Automatic Interpretation in ECG Signals
Authors: Gordillo-Roblero Luis Alberto , Soto-Cajiga Jorge Alberto , Díaz-Alonso Daniela , Pérez-Reynoso Francisco David , Jiménez-Hernández Hugo
Published: March 2024

Numerous papers report the efficiency of the automatic interpretation capabilities of commercial algorithms. Unfortunately, these algorithms are proprietary, and academia has no means of directly contributing to these results. In fact, nothing at the same stage of development exists in academia. Despite the extensive research in ECG signal processing, from signal conditioning to expert systems, a cohesive single application for clinical use is not ready yet. This is due to a serious lack of coordination in the academic efforts, which involve not only algorithms for signal processing, but also the signal acquisition equipment itself. For instance, the different sampling rates and the different noise levels frequently found in the available signal databases can cause severe incompatibility problems when the integration of different algorithms is desired. Therefore, this work aims to solve this incompatibility problem by providing the academic community with a diagnostic-grade electrocardiograph. The intention is to create a new standardized ECG signals database in order to address the automatic interpretation problem and create an electrocardiography system that can fully assist clinical practitioners, as the proprietary systems do. Achieving this objective is expected through an open and coordinated collaboration platform for which a webpage has already been created.
Three-Dimensional Virtual Reconstruction of External Nasal Defects Based on Facial Mesh Generation Network
Authors: Qin Qingzhao , Li Yinglong , Wen Aonan , Zhu Yujia , Gao Zixiang , Shan Shenyao , Wu Hongyu , Zhao Yijiao , Wang Yong
Published: March 2024

(1) Background: In digital-technology-assisted nasal defect reconstruction methods, a crucial step involves utilizing computer-aided design to virtually reconstruct the nasal defect’s complete morphology. However, current digital methods for virtual nasal defect reconstruction have yet to achieve efficient, precise, and personalized outcomes. In this research paper, we propose a novel approach for reconstructing external nasal defects based on the Facial Mesh Generation Network (FMGen-Net), aiming to enhance the levels of automation and personalization in virtual reconstruction. (2) Methods: We collected data from 400 3D scans of faces with normal morphology and combined the structured 3D face template and the Meshmonk non-rigid registration algorithm to construct a structured 3D facial dataset for training FMGen-Net. Guided by defective facial data, the trained FMGen-Net automatically generated an intact 3D face that was similar to the defective face, and maintained a consistent spatial position. This intact 3D face served as the 3D target reference face (3D-TRF) for nasal defect reconstruction. The reconstructed nasal data were extracted from the 3D-TRF based on the defective area using reverse engineering software. The ‘3D surface deviation’ between the reconstructed nose and the original nose was calculated to evaluate the effect of 3D morphological restoration of the nasal defects. (3) Results: In the simulation experiment of 20 cases involving full nasal defect reconstruction, the ‘3D surface deviation’ between the reconstructed nasal data and the original nasal data was 1.45 ± 0.24 mm. The reconstructed nasal data, constructed from the personalized 3D-TRF, accurately reconstructed the anatomical morphology of nasal defects. (4) Conclusions: This paper proposes a novel method for the virtual reconstruction of external nasal defects based on the FMGen-Net model, achieving the automated and personalized construction of the 3D-TRF and preliminarily demonstrating promising clinical application potential.
The Association between the Dental Status and Tongue Thrust Habits of Latvian Preschool Children and Their Mothers’ Oral Health Knowledge
Authors: Tzivian Lilian , Priede Dace , Folkmanis Valdis , Henkuzena Ieva
Published: March 2024

Objectives: The aim of this study was to describe the factors that affect the normal dental development of preschool children in Latvia, and to investigate sources that mothers use to get information on children’s oral health. Materials and Methods: A cross-sectional study was performed in two kindergartens in Latvia (cluster sampling). The study sample comprised 141 child–mother pairs of preschool children aged 4–7 years. The dental situation of all children was assessed including evaluation by an orthodontist and a speech therapist, and mothers of children filled out the survey on oral health-related habits and information about it. Statistical analysis: We described individually factors related to orthodontal situations, children’s speech problems, and factors that can affect tongue thrust. We investigated relationships between sources of mothers’ information and oral health-related behaviors using univariate (Kruskal–Wallis test, a chi-squared test, a Fisher test, or Cramer’s V test) and multivariate analyses. We built a multiple logistic regression model adjusted for the demographic and oral health-related factors to investigate the factors associated with tongue thrust. Results of multiple logistic regression were presented with odds ratio (OR) and 95% confidence intervals (CI). Results: In total, 36.9% of children grazed vegetables several times a week, and 61.0% cleaned their teeth twice a day. Of mothers, 12% did not receive any information about child dental care from their general physician, and 23.4% found the received information insufficient. A total of 43.3% of mothers received oral health-related information from friends, and it was significantly related to less carbonated water (p < 0.01), more help during teeth cleaning (p = 0.03), starting cleaning teeth in earlier age (p = 0.03), and more frequent visits to a child dentist (p = 0.03). Conclusions: A lack of knowledge was found to be prominent in mothers of kindergarten children in Latvia, and most of them received information not from official sources such as their general physician. This can be related to some problems in oral health behaviors and oral health-related diseases. Communication among dental health specialists, state authorities, and families is crucial for the improvement of children’s dental situation.
Improving Equitable Access to Graduate Education by Reducing Barriers to Minoritized Student Success
Authors: Rehfeld David M. , Renbarger Rachel , Sulak Tracey , Kugler Abby , DeMeyer Payton
Published: March 2024

Structural inequities in graduate education perpetuate inequity for students with historically minoritized identities. This paper reviews previous reports of inequities faced by students with minoritized identities and suggests a path forward for improving equitable access to doctoral study. Specifically, this paper suggests investing in the scholarship of teaching and learning while using Gardner’s model of doctoral student development to provide targeted support at different levels of operation: the institution, the department, and the individual. Evidence for suggested supports is also provided and a call for further research on the effects of such programs for recruitment, retention, and graduation of minoritized students is made.
Data Quality of Different Modes of Supervision in Classroom Surveys
Authors: Stefes Till
Published: March 2024

Conducting quantitative research involving adolescents demands a thoughtful approach to the question of supervision, given that each option comes with its distinct set of implications. This study reviews these implications and empirically tests whether differences in data quality can be found among three modes of standardized survey research with medium-sized groups of adolescents (12–17 years). The data basis is a quasi-experimental survey study testing different forms of digital, hybrid, or in-person supervision that took place in 2021 in secondary schools in Germany (N = 923). The aim of this study is to test how aspects of data quality—item nonresponse, interview duration, drop-out rate, and response patterns—differ between these forms of supervision. Results could help researchers surveying young people to decide (1) whether they allow confidants or other adults to be present during interviews, (2) if they can rely on teachers alone when surveying classrooms, and (3) if it is cost-efficient to send out external supervisors for classroom sessions. While drop-out rates do not differ, item non-response, interview duration, and response patterns differ significantly; students supervised at home by external interviewers answered more questions, took more time to answer, and were less likely to give potentially meaningless answers in grid questions. The implications drawn from the findings question the common approach of solely relying on teachers for survey administration without the support of external supervisors or adequate training. Recruiting respondents via schools and surveying them online in their homes during school hours has been shown to be a robust method with regard to the analyzed indicators.
Decentralised Voltage Regulation through Optimal Reactive Power Flow in Distribution Networks with Dispersed Generation
Authors: Daccò Edoardo , Falabretti Davide , Ilea Valentin , Merlo Marco , Nebuloni Riccardo , Spiller Matteo
Published: March 2024

The global capacity for renewable electricity generation has surged, with distributed photovoltaic generation being the primary driver. The increasing penetration of non-programmable renewable Distributed Energy Resources (DERs) presents challenges for properly managing distribution networks, requiring advanced voltage regulation techniques. This paper proposes an innovative decentralised voltage strategy that considers DERs, particularly inverter-based ones, as autonomous regulators in compliance with the state-of-the-art European technical standards and grid codes. The proposed method uses an optimal reactive power flow that minimises voltage deviations along all the medium voltage nodes; to check the algorithm’s performance, it has been applied to a small-scale test network and on a real Italian medium-voltage distribution network, and compared with a fully centralised ORPF. The results show that the proposed decentralised autonomous strategy effectively improves voltage profiles in both case studies, reducing voltage deviation by a few percentage points; these results are further confirmed through an analysis conducted over several days to observe how seasons affect the results.
Research and Design of a Chicken Wing Testing and Weight Grading Device
Authors: Wang Kelin , Li Zhiyong , Wang Chengyi , Guo Bing , Li Juntai , Lv Zhengchao , Ding Xiaoling
Published: March 2024

This thesis introduces a nondestructive inspection and weight grading device for chicken wings to replace the traditional manual grading operation. A two-sided quality nondestructive inspection model of chicken wings based on the YOLO v7-tiny target detection algorithm is designed and deployed in a Jetson Xavier NX embedded platform. An STM32 microcontroller is used as the main control platform, and a wing turning device adapting to the conveyor belt speed, dynamic weighing, and a high-efficiency intelligent grading unit are developed, and the prototype is optimized and verified in experiments. Experiments show that the device can grade four chicken wings per second, with a comprehensive accuracy rate of 98.4%, which is better than the traditional grading methods in terms of efficiency and accuracy.
Nonlinear Controller-Based Mitigation of Adverse Effects of Cyber-Attacks on the DC Microgrid System
Authors: Ali Mohd. Hasan , Akhter Sultana Razia
Published: March 2024

Cyber-attacks have adverse impacts on DC microgrid systems. Existing literature shows plenty of attack detection methods but lacks appropriate mitigation and prevention approaches for cyber-attacks in DC microgrids. To overcome this limitation, this paper proposes a novel solution based on a nonlinear controller to mitigate the adverse effects of various cyber-attacks, such as distributed denial of service attacks and false data injection attacks, on various components of a DC microgrid system consisting of a photovoltaic power source, a permanent magnet synchronous generator-based variable speed wind generator, a fuel cell, battery energy storage, and loads. To demonstrate the effectiveness of the proposed solution, single and repetitive cyber-attacks on specific components of the microgrid have been considered. An index-based quantitative improvement analysis for the proposed control method has been made. Extensive simulations have been performed by the MATLAB/Simulink V9 software. Simulation results demonstrate the effectiveness of the proposed nonlinear controller-based method in mitigating the adverse effects of cyber-attacks. Moreover, the performance of the proposed method is better than that of the proportional-integral controller. Due to the simplicity of the proposed solution, it can easily be implemented in real practice.
An All-Digital Timing Mismatch Calibration Algorithm Based on Reference Channel for TIADC
Authors: Zhong Wei , Dong Yemin , Lang Lili , Xiong Wei , Sun Lin , Liu Yu , Liu Haijing , Zhang Zhenwei
Published: March 2024

This paper proposes an all-digital calibration algorithm that utilizes a reference channel to suppress the timing mismatch in the Time-Interleaved Analog-to-Digital Converter (TIADC). The output of the reference channel is aligned with each sub-channel in turn, therefore enabling the simultaneous sampling and conversion of the same input signal. First, the statistical characteristics across the channels are employed for estimating the timing mismatch; then, by comparing the output difference between the reference channel and the sub-channels that are sampled simultaneously, the deviation of the derivator can be calibrated. Finally, combining both calibration results yields an accurate final output. This proposed algorithm provides an effective solution to improve TIADC performance in high-speed data acquisition systems. The proposed architecture is applied to a 12-bit 2.4 GS/s four-channel TIADC model, and then its effectiveness is verified. The simulation results exhibit that the Effective Number Of Bits (ENOB) at an input signal frequency of 984 MHz shows a remarkable improvement from 6.88 bits to 11.92 bits. The effectiveness of this technique is also demonstrated through the off-chip calibration of a commercial 12-bit four-channel 2 GS/s TIADC using a 680 MHz input signal that is based on the actual chip results.
Characteristics, Controlling Factors and Reservoir Quality Implications of Inner Fracture Zones in Buried Hills of Archean Covered Metamorphic Rock in Block 13-2, Bozhong Depression
Authors: Lu Junjie , Shan Xuanlong , Yi Jian , Li Huiyong , Xu Peng , Hao Guoli , Li Ang , Yin Shuai , Ren Shuyue , Liu Chaoyang , Shi Yunqian
Published: March 2024

Inner fracture zones play a decisive role in the formation of high-quality reservoirs in buried hill reservoirs in covered metamorphic rock. Based on core, sidewall core, thin section, seismic, logging and reservoir physical property data, the fracture development characteristics of the Bozhong 13-2 block buried hill reservoir are described in detail and the controlling factors and the influence on reservoir quality are discussed. The results showed: (1) three groups of tectonic fractures developed in the study area—near-EW-striking, ENE-striking and nearly N–S-striking fractures—were controlled by the early Indosinian thrusting, the late Indosinian to early Yanshanian sinistral strike-slipping and the late Yanshanian late dextral strike-slipping in the Bohai Bay Basin, respectively. The ENE- and nearly-E-W-striking fractures are the most common, and the dip angles of the fractures are mostly between 35° and 75° and thus oblique. (2) The Indosinian-early Yanshanian was the main fracture-forming period, and the dextral strike-slip action in the late Yanshanian was the key to maintaining effective fractures. Imaging logging shows that 97.87% of the fractures are effective fractures. Based on thin section observation, 14.47% of the fractures are unmodified open fractures and 80.37% of the fractures are effective fractures due to reactivation. (3) The late Yanshanian strike-slip fault transformed the deformation adjustment zone formed by the early Indosinian thrust faulting and the core of the fold structure was more conducive to fracture development. The fracture density of a single well located within the deformation adjustment zone and at the core of the fold is between 0.93–1.49 m−1, the fracture density of a single well located only at the core of the fold is between 0.67–0.75 m−1 and that of a single well located at the wing of the fold is between 0.35–0.59 m−1. Diabase dike intrusions promoted the development of local fractures. (4) Fractures promote the migration and accumulation of oil and gas, and the fracture density in the oil layer is between 0.81–2.19 m−1. That in the nonoil layer is between 0.25–1.12 m−1. In addition, fractures not only provide storage space but also effectively improve the reservoir capacity of the inner fracture zones of buried hill reservoirs by concentrating dissolution.
Initial Occurrence State and Movability Evaluation of the Gulong Shale Oil Reservoir, Songliao Basin
Authors: Zhao Guozhong , Cheng Linsong , Jia Pin , Liu Yong , Feng Haoran , Kuang Tie , Wang Qingzhen
Published: March 2024

The Qing-1 layer of the Gulong Depression in the northern Songliao Basin is a liquid-rich shale oil reservoir that has the characteristics of nanopores, high maturity, high gas/oil ratio (GOR), etc. The production performance of wells in the Gulong shale oil reservoir shows the characteristics of “single gas production followed by oil-gas production”. It is difficult to analyze the initial occurrence state and movability of fluid in the shale nanopores using conventional methods. In this study, a comprehensive method, including phase behavior analysis, physical experiments, and molecular simulation, was established to analyze the initial occurrence state and movability of fluid in the Gulong shale oil reservoir. The phase state of the fluid was calculated by the equation of state (EOS), considering nano-confinement effects, and the initial occurrence state was quantitatively evaluated by combining two-dimensional nuclear magnetic resonance (NMR) and molecular dynamics simulation. The movable fluid saturation was quantitatively determined by centrifugal experiments. The results show that the condensate gas state was in small pores, while the volatile oil state was in large pores. The occurrence states of oil were mainly adsorbed oil and free oil. The proportion of adsorbed oil in inorganic pores was about 24.4%, while the proportion of absorbed oil in organic pores was about 57.8%. Based on the cutoff value of T2 before and after the centrifuged laboratory experiments, the movable limit of oil was determined to be 4.5 nm, and the movable fluid saturation was about 11%. The research method proposed in this study has important guiding significance for the initial occurrence state and movability evaluation of similar liquid-rich shale reservoirs.
A Pressure-Oscillation-Based RON Estimation Method for Spark Ignition Fuels beyond RON 100
Authors: Robeyn Tom , Sileghem Victor , Larsson Tara , Verhelst Sebastian
Published: March 2024

Knock in spark ignition (SI) engines occurs when the air–fuel mixture in the combustion chamber ignites spontaneously ahead of the flame front, reducing combustion efficiency and possibly leading to engine damage if left unattended. The use of knock sensors to prevent it is common practice in modern engines. Another measure to mitigate knock is the use of higher-octane fuels. The American Society for Testing and Materials’ (ASTM) determination of the Research Octane Number (RON) and Motor Octane Number (MON) of spark ignition fuels has been based on measuring cylinder pressure rise at the onset of knock since its inception in the 1930s. This is achieved through a low-pass filtered pressure signal. Knock detection in contemporary engines, however, relies on measuring engine vibrations caused by high-frequency pressure oscillations during knock. The difference between conditions in which fuels are evaluated for their octane rating and the conditions that generate a knock intensity signal from the knock sensor suggests a potential difference between octane rating and the knock limit typically identified by a contemporary knock sensor. To address this disparity, a modified RON measurement method has been developed, incorporating pressure oscillation measurements. This test method addresses the historical lack of correlation between RON and high-frequency pressure oscillation intensity during knock. Using toluene standardization fuels (TSFs) as a reference, the obtained results demonstrate excellent high-frequency knock intensity-based RON estimations for gasoline. The method is able to differentiate between two fuels that share the same ASTM RON, associating them with a RON-like metric that is more aligned with their performance in a modern SI engine. This alternative method could potentially serve as a template for an upgrade to the existing ASTM RON method without significantly disrupting the current approach. Additionally, its capability to evaluate fuels beyond RON 100 opens the door to assessing a wider range of fuels for antiknock properties and the intensity of fuel oscillations during knocking combustion.
Experimental Transient Process Analysis of Micro-Turbojet Aviation Engines: Comparing the Effects of Diesel and Kerosene Fuels at Different Ambient Temperatures
Authors: Cican Grigore
Published: March 2024

In this paper, we investigate the impact of diesel and kerosene on the transient processes occurring in a micro-turbojet aviation engine. The experiments were conducted under two distinct ambient temperature conditions, 0 and 20 °C. Specifically, we analyzed the starting phase of the micro-engine while operating with kerosene and diesel at both ambient temperature settings. Comparative graphs were generated, and the starting time was meticulously examined. Subsequently, we constructed performance maps for the engine using both fuels and across the two ambient temperature scenarios. We then executed a transient process, comprising sudden acceleration and deceleration, under the aforementioned ambient temperature conditions and with both fuels. The fluctuations in temperature within the combustion chamber, thrust force, and fuel consumption are presented for both rapid acceleration and deceleration events. Furthermore, we conducted comparisons between the thrust force, fuel flow rate, combustion chamber temperature, and specific fuel consumption for the two fuels tested and under the two ambient temperature conditions, both during idle and at higher engine regimes. In the idle regime at 0 °C, the kerosene flow is about 0.78% higher than diesel, with the kerosene thrust approximately 1.92% greater. At 20 °C, the kerosene consumption rises by roughly 5.56% compared to diesel, while the thrust increases by about 1.38%. It was observed that at the maximum operating regime, at 0 °C, the kerosene flow exceeds diesel by around 6%, with the kerosene thrust slightly higher, by about 0.63%. At 20 °C, the kerosene consumption rises by roughly 13.19% compared to diesel, while the thrust increases by about 5.91%. In higher regimes, the kerosene consumption surpasses diesel, but the thrust increase is not significant. Thus, diesel’s use as a fuel for the microturbo engine is justified due to its lower consumption at both 0 °C and 20 °C.
Light and Light Signals Regulate Growth and Development in Woody Plants
Authors: Bao Yu , Liu Xiao , Feng Cong-Hua , Niu Meng-Xue , Liu Chao , Wang Hou-Ling , Yin Weilun , Xia Xinli
Published: March 2024

This review synthesizes the current understanding on the dynamic influence of light on the developmental morphology of woody plants. It explores the regulatory effects of photosynthesis and photomorphogenesis in response to varying light conditions including intensity, quality, and photoperiodicity, and their subsequent impact on plant growth and architecture. Additionally, this review elucidates the role of the circadian system in synchronizing internal rhythms with external light cycles, a process mediated by photoreceptors such as PHYTOCHROME A (PHYA) and PHYTOCHROME B (PHYB), which are pivotal for seasonal growth and dormancy in species like poplar. The molecular perspective is provided on the light-regulated transcription of genes, along with their influence on the plant’s growth cycles and seasonal adaptions. Furthermore, the interactive role of plant hormones, including auxin, ethylene, and abscisic acid (ABA), is explored in the context of light signal transduction and its subsequent effect on plant physiology. By providing a comprehensive view of the light-dependent mechanisms that govern woody plant growth, this review contributes to our understanding of plant adaptation strategies and informs approaches to enhance forestry production and biodiversity conservation in the face of climate change.
Simultaneous Saccharification and Fermentation for Isobutanol Production from Banana Peel
Authors: Akita Hironaga , Shibata Shodai , Komoriya Tomoe , Kamei Shinnosuke , Asamoto Hiromichi , Matsumoto Masakazu
Published: March 2024

Each year, near 40 million tons of banana peels are discarded around the world. This plant biomass could potentially be utilized for energy production. Simultaneous saccharification and fermentation (SSF) is an effective method for producing biofuels from plant biomasses. Since SSF with enzymatic hydrolysis and fermentation are performed simultaneously in the same reactor, the production process is simpler than most existing methods. Here, we describe isobutanol production using SSF with hydrothermally treated banana peel samples and an Escherichia coli strain able to utilize glucose and xylose to produce isobutanol. To enhance the glucose and xylose concentrations, the reaction conditions for the enzymatic hydrolysis of plant biomass using two kinds of saccharification enzymes were optimized, including the enzyme unit ratio, reaction temperature and sample gram. When the optimized conditions for enzymatic hydrolysis were applied to SSF, the glucose and xylose produced from the hydrothermally treated samples were consumed, producing isobutanol. Moreover, the isobutanol concentration increased with an increasing initial culture pH, reaching 1.27 g/L at pH 6.5, which was consistent with the optimal initial culture pH for isobutanol production by this E. coli strain. Taken together, these results indicate that the established method is potentially useful for industrial isobutanol production.
Developments of Core/Shell Chitosan-Based Nanofibers by Electrospinning Techniques: A Review
Authors: Taokaew Siriporn , Chuenkaek Tapanee
Published: March 2024

This review is focused on the recent development of various chitosan-based nanofibers (membranes, patches, mats, and scaffolds) that have been designed into core and shell structures using emulsion and coaxial electrospinning techniques. Chitosan, a promising polysaccharide derived from natural sources, holds potential for diverse applications, including nanofiber production, aimed at fostering sustainability. Core/shell chitosan-based nanofibers offer appealing features, including drug encapsulation and sustained release capabilities, with a higher efficiency than uniaxial fibers. The fabrication of core/shell chitosan-based nanofibers, including the co-spinning agents and various spinning parameters, such as spinning voltage, needle size, spinning flow rate, distance from needle tip to collector, temperature, and humidity, is summarized in this work. The review also explores updated applications in various fields, such as textiles, medical dressings, drug release systems, filtration membranes, and food packaging. It highlights the current advancements in core/shell chitosan-based nanofibers produced via electrospinning techniques. The innovative insights presented in the recent literature and the challenges associated with these sustainable materials are thoroughly examined, offering valuable contributions to the field.
The Fractal Approach to Describe Growth of Farmed Marine Species: Using Double and Triple Logistic Models
Authors: Rodríguez-Domínguez Guillermo , Aragón-Noriega Eugenio Alberto , Payán-Alejo Jorge , Mendivil-Mendoza Jaime Edzael , Curiel-Bernal Marcelo Vidal , Valenzuela-Quiñonez Wenceslao , Urías-Sotomayor Ricardo
Published: March 2024

Modeling individual growth in marine species for aquaculture encounters many difficulties when the species pauses its growth but resumes its later after the disrupting phenomenon (environmental or physiological) has been overcome. Seasonal or oscillatory growth has been addressed by modifying existing models, such as von Bertalanffy and Gompertz, to include an oscillatory component in this study. The novelty of this study lies in the fractal approach used to analyze growth using multiple logistic functions. Three commercially farmed marine species were studied, including shellfish, crustacea, and finfish. The oscillatory version of the von Bertalanffy model as well as double and triple logistic functions were used for analysis. The best model was selected using the information theory, Specifically the Akaike criterion (AIC) and the Bayesian criterion (BIC). Normal and log-normal distributions of error were assumed. The triple logistic model with log-normal distribution in the error structure was found to be the best model to describe the growth pattern of the three commercially farmed species as it obtained the lowest AIC. Overall, this study concludes that the fractal approach is the most effective way to describe growth in farmed species, including shellfish, crustacean, and finfish.
Event-Triggered Adaptive Fuzzy Control for Strict-Feedback Nonlinear FOSs Subjected to Finite-Time Full-State Constraints
Authors: Wang Changhui , Li Wencheng , Liang Mei
Published: March 2024

In this article, an event-triggered adaptive fuzzy finite-time dynamic surface control (DSC) is presented for a class of strict-feedback nonlinear fractional-order systems (FOSs) with full-state constraints. The fuzzy logic systems (FLSs) are employed to approximate uncertain nonlinear functions in the backstepping process, the dynamic surface method is applied to overcome the inherent computational complexity from the virtual controller and its fractional-order derivative, and the barrier Lyapunov function (BLF) is used to handle the full-state constraints. By introducing the finite-time stability criteria from fractional-order Lyapunov method, it is verified that the tracking error converges to a small neighborhood near the zero and the full-state constraints are satisfied within a predetermined finite time. Moreover, reducing the communication burden can be guaranteed without the occurrence of Zeno behavior, and the example is given to demonstrate the effectiveness of the proposed controller.
Analysis of Pore Characterization and Energy Evolution of Granite by Microwave Radiation
Authors: Zhou Keping , Zhang Yifan , Yang Chun , Yang Niange , Pan Zheng
Published: March 2024

To study the dynamic response of granite to different levels of microwave power, an intelligent microwave rock-breaking instrument is used to irradiate different power from three directions. The servo universal testing machine is used to carry out a uniaxial compression test on the granite after microwave damage to analyze the strength damage characteristics and the degree of pore damage. Pore fractal characteristics are analyzed based on nuclear magnetic resonance to establish the microwave damage degradation model. In parallel, the energy evolution process of granite under the influence of various power levels is analyzed using the theory of energy dissipation. Simultaneously, based on the energy dissipation theory, we analyze the energy evolution process of granite under the action of different powers. The results show that with higher microwave power, the peak strength and modulus of elasticity show a linear decreasing law. The degree of fragmentation is more obvious, showing the damage characteristics with two big ends and little in the middle. The higher the power, the greater the porosity and the more sensitive the micropore becomes to microwaves. Additionally, the damage degradation model established to evaluate the microwave damage of the rock showed that it was feasible. The higher the power, the lower the total energy, elastic energy, and dissipation energy, and the granite is gradually transformed from elastic deformation to plastic deformation. The elastic energy ratio decreases, the dissipation energy ratio increases, and the degree of damage becomes more and more serious. This study provides theoretical support for exploring the mechanical behavior and mechanism of microwave-assisted rock breaking and is of great practical significance.
A New Approach to Multiroot Vectorial Problems: Highly Efficient Parallel Computing Schemes
Authors: Shams Mudassir , Rafiq Naila , Carpentieri Bruno , Ahmad Mir Nazir
Published: March 2024

In this article, we construct an efficient family of simultaneous methods for finding all the distinct as well as multiple roots of polynomial equations. Convergence analysis proves that the order of convergence of newly constructed family of simultaneous methods is seventeen. Fractal-based simultaneous iterative algorithms are thoroughly examined. Using self-similar features, fractal-based simultaneous schemes can converge to solutions faster, saving computational time and resources necessary for solving nonlinear equations. Fractals analysis illustrates the newly developed method’s global convergence behavior when compared to single root-finding procedures for solving fractional order polynomials that arise in complex engineering applications. Some real problems from various branches of engineering along with some higher degree polynomials are considered as test examples to show the global convergence property of simultaneous methods, performance and efficiency of the proposed family of methods. Further computational efficiencies, CPU time and residual graphs are also drawn to validate the efficiency, robustness of the newly introduced family of methods as compared to the existing methods in the literature.
Characterization of Beeswax and Rice Bran Wax Oleogels Based on Different Types of Vegetable Oils and Their Impact on Wheat Flour Dough Technological Behavior during Bun Making
Authors: Ropciuc Sorina , Dranca Florina , Oroian Mircea Adrian , Leahu Ana , Prisacaru Ancuţa Elena , Spinei Mariana , Codină Georgiana Gabriela
Published: March 2024

Five varieties of vegetable oil underwent oleogelation with two types of wax as follows: beeswax (BW) and rice bran wax (RW). The oleogels were analyzed for their physicochemical, thermal, and textural characteristics. The oleogels were used in the bun dough recipe at a percentage level of 5%, and the textural and rheological properties of the oleogel doughs were analyzed using dynamic and empirical rheology devices such as the Haake rheometer, the Rheofermentometer, and Mixolab. The thermal properties of beeswax oleogels showed a melting peak at a lower temperature for all the oils used compared with that of the oleogels containing rice bran wax. Texturally, for both waxes, as the percentage of wax increased, the firmness of the oleogels increased proportionally, which indicates better technological characteristics for the food industry. The effect of the addition of oleogels on the viscoelastic properties of the dough was measured as a function of temperature. All dough samples showed higher values for G′ (storage modulus) than those of G″ (loss modulus) in the temperature range of 20–90 °C, suggesting a solid, elastic-like behavior of all dough samples with the addition of oleogels. The influence of the beeswax and rice bran oleogels based on different types of vegetable oils on the thermo-mechanical properties of wheat flour dough indicated that the addition of oleogels in dough recipes generally led to higher dough stability and lower values for the dough development time and those related to the dough’s starch characteristics. Therefore, the addition of oleogels in dough recipes inhibits the starch gelatinization process and increases the shelf life of bakery products.
The Ordinary Looks behind the Horrifying Screams: The Secrecies of Border Spirits in 20th Century Finnish Belief Narratives
Authors: Korolainen Kari
Published: March 2024

This paper discusses the secrecies of border spirits within 20th century Finnish belief narratives. The aim is to explore how and in which contexts the imaginary aspects of border spirit narratives link to the idea of the “power of storytelling”. The following study touches on areas such as the suspension of the fantasy and sociopolitical aspects within the narratives. The folklore materials focus mainly on the Finnish heartland and partly on the national borders. Especially, narrative research methods were used to analyse what is heard and seen of the border spirits and what contexts these narratives involve. Moreover, the results touch on the dynamics of belief narratives without limiting them to the territorial aspects of borders. Hence, the study also explores interpretative bridges between folklore and border studies.