bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring the intersections of frailty, sarcopenia, and cachexia with malnutrition
Authors: Jensen Gordon L. , Cederholm Tommy
Published: June 2024

This review examines our current understanding of consensus definitions for frailty, sarcopenia, and cachexia and their perceived overlap with malnutrition. Patients with these syndromes will often meet the criteria for malnutrition. It is common for these overlap syndromes to be misapplied by practitioners, and confusion has been further exacerbated by the lack of a common malnutrition language. To address the latter concern, we recommend using either the standalone Global Leadership Initiative in Malnutrition (GLIM) framework or the GLIM consensus criteria integrated with other accepted approaches as dictated by preference and available resources. Established care standards should guide the recognition and treatment of malnutrition to promote optimal clinical outcomes and quality of life. The effectiveness of nutrition interventions may be reduced in settings of severe acute inflammation and in end‐stage disease that is associated with cachexia. However, such interventions may still assist patients to tolerate treatments that target the underlying etiology for an overlap syndrome, and they may help to improve select clinical outcomes and quality of life. Recent, large, well‐designed randomized controlled trials have demonstrated the compelling positive clinical effects of medical nutrition therapy. The application of concurrent malnutrition risk screening and assessment is therefore a high priority. The necessity to deliver specific interventions that target the underlying mechanisms of these overlap syndromes and also diagnose and address malnutrition is paramount. It must be highlighted that securing beneficial outcomes for frailty, sarcopenia, and cachexia will also require nonnutrition interventions, like comprehensive care plans, pharmacologic agents, and prescribed exercise.
Post‐stroke family resilience is correlated with family functioning among stroke survivors: The mediating role of patient's coping and self‐efficacy
Authors: Zhang Wei , Gao Ya‐Jing , Ye Ming‐Ming , Zhou Lan‐Shu
Published: June 2024

Aim

Family resilience and healthy family functioning are crucial for stroke survivors' rehabilitation. This study aimed to determine the mediating effects of self‐efficacy and confrontation coping on the relationship between family resilience and functioning among patients with first‐episode stroke.

Design

A cross‐sectional design was applied.

Methods

288 patients with first‐episode stroke were recruited from 7 hospitals in Shangqiu and Shanghai, China, from July 2020 to October 2020. A shortened Chinese version of the Family Resilience Assessment Scale, family adaptation, partnership, growth, affection and resolve questionnaire, Medical Coping Modes Questionnaire, and Self‐efficacy for Chronic Disease 6‐item Scale were used to collect the self‐reported data. The relationships among the studied variables were studied using spearman correlation and structural equation model.

Results

The average level of family functioning among stroke patients was 7.87 (SD = 2.32). About 26.8% (n = 76) of patients reported family dysfunction. The structural equation model showed that family resilience directly affected patients' satisfaction with family functioning (r = 0.406, p < 0.001) and indirectly affected the mediating role of patients' self‐efficacy and confrontation coping style (r = 0.119, p < 0.001). The model was with good fit (χ2/df = 2.128, RMSEA = 0.065, GFI = 0.956, AGFI = 0.919, NFI = 0.949, and TLI = 0.956).

Conclusion

Family resilience and functioning among patients with first‐episode stroke are positively associated with the mediating effects of the patients' confrontation coping style and self‐efficacy between family resilience and functioning. The findings indicate that the professionals should pay special attention to families exhibiting poor family resilience or with patients who rarely use confrontation coping styles or with poor self‐efficacy since they are more likely to suffer from low functioning.
Modification of Hydrotalcite Loading Tannic Acid with Organic Silane and Application in Anticorrosive Epoxy Coating
Authors: Quy Bui Minh , Chinh Nguyen Thuy , Anh Nguyen Thi Kim , Tuyet Vu Thi , Thai Nguyen Xuan , Trung Vu Quoc , Quyen Ngo Thi Cam , Tan Nguyen Ngoc , Hoang Thai
Published: June 2024

Metal corrosion is a challenge for the world with heavy impacts on the economy. Study on the development of effectiveness anticorrosion additives is a promising strategery for the protection industry. This research focuses on the modification of hydrotalcite Mg−Al (HT) loading tannic acid (TA) with 3‐(trimethoxy silyl) propyl methacrylate organo‐silane (TMSPM) for applicating as an anti‐corrosion additive for epoxy coating on the steel substrate. The suitable ratio of HT and modifiers was investigated and the suitable content of modified HT in epoxy matrix was found based on mechanical properties of the epoxy‐based coating. The characteristics of modified HT were assessed through infrared (IR) spectroscopy, X‐ray diffraction pattern (XRD), scanning electron microscopy (SEM), thermal gravimetry analysis (TGA), water contact angle (WCA), dynamic light scattering (DLS). Detailly, HT‐TA3‐S3 shows good stability in distilled water when HT/TA was modified with TMSPM which makes Zeta potential decreases significantly. Besides, SEM analysis presented HT‐TA‐S has a cylindrical shape about of 500 nm. Moreover, the crystallite size of HT/TA after being modified by TMSPM decreases sharply. All of these prove successfully synthesize HT loading TA with modified TMSPM. Water contact angle (WCA) decreases in case of loading TA and increases in case of modifying with TMSPM (WCA changed from HT (116.3°) to HT‐TA (102.4°) and HT‐TA‐S (120.1°) which indicates the increased hydrophobicity of the sample. The obtained results showed HT/TA was modified successfully with TMSPM. The modification affected the size distribution and surface properties of HT nanoparticles while it did not impact on the crystal structure of HT. After incorporating modified HT/TA into the epoxy coating, the adhesion of coating to steel substrate was improved significantly. Consequently, the adhesion of epoxy/3 wt. % modified HT/TA coating was increased 3 times as compared to epoxy neat (from 0.76 MPa to 2.77 MPa). In addition, the relative hardness and gloss retention of epoxy/3 wt. % modified HT/TA coating reached the maximum values as compared to the others. Owing to salt spraying results, the epoxy/3 wt. % modified HT/TA exhibited an excellent anticorrosion ability for the steel substrate. All the above results show the potential of HT nanoparticles loading TA modified with TMSPM as anticorrosive additives for protective coatings on steel substrates.
Beyond the model minority myth: Student–counselor interactions and college enrollment of Asian American students
Authors: Kim Jungnam , Kim Hyunhee , Woo Hong Ryun , Chen Ching‐Chen , Park Sangmin
Published: June 2024

Due to the model minority myth, scant attention has been given to the college preparation of Asian American (AA) students. Using the national sample of High School Longitudinal Study of 2009–2013, this study examined associations among student–counselor interactions, school connectedness, and college enrollment of AA students. The results of the structural equation modeling indicated that school connectedness fully mediated the association between student–counselor interactions and college enrollment. The findings from the current study suggest that when AA students interact with school counselors in the 9th grade, they tend to feel more connected to their school, which, in turn, leads to increased college enrollment decisions in the 12th grade. Implications for helping professionals in schools are discussed.
An evaluation of digital inclusion response policies for elderly in China
Authors: Zhao Ying , Zhu Boyu
Published: June 2024

Digital inclusion is related to the physical and mental health of the elderly, and the relevant policies formulated by the government have an important impact on it. This article analyzes 69 policies related to digital inclusion of the elderly released by the central government of China. The results of the content analysis show that the current policies generally attach importance to the service and building of digital inclusion for the elderly, and gradually shift the policy focus to aging adaptation, smart device use, and learning guidance. The evaluation results using a policy modeling consistency index (PMC‐Index) indicate that the quality of the current Chinese government's policies to help the digital inclusion of the elderly is generally high. However, PMC‐Surface shows that there is still considerable variability in the scores of the main‐indicators for each policy. The evaluation results suggest that we can still improve the effectiveness of policies by expanding the scope of policy audiences, establishing good policy timeliness planning, and enriching policy contents, so as to effectively help the elderly integrate into the current rapidly developing digital society.
Determination of a vancomycin nephrotoxicity threshold and assessment of target attainment in hematology patients
Authors: Wong Sherilyn , Selby Philip R. , Reuter Stephanie E.
Published: June 2024

An area‐under‐the‐curve (AUC24)‐based approach is recommended to guide vancomycin therapeutic drug monitoring (TDM), yet trough concentrations are still commonly used despite associated risks. A definitive toxicity target is lacking, which is important for hematology patients who have a higher risk of nephrotoxicity. The aims were to (1) assess the impact of trough‐based TDM on acute kidney injury (AKI) incidence, (2) establish a vancomycin nephrotoxicity threshold, and (3) evaluate the proportion of hematology patients achieving vancomycin therapeutic targets. Retrospective data was collected from 100 adult patients with a hematological malignancy or aplastic anemia who received vancomycin between April 2020 and January 2021. AKI occurrence was determined based on serum creatinine concentrations, and individual pharmacokinetic parameters were estimated using a Bayesian approach. Receiver operating characteristic (ROC) curve analysis was performed to assess the ability of pharmacokinetic indices to predict AKI occurrence. The proportion of patients who achieved target vancomycin exposure was evaluated based on an AUC24/MIC ≥400 and the determined toxicity threshold. The incidence of AKI was 37%. ROC curve analysis indicated a maximum AUC24 of 644 mg.h/L over the treatment period was an important predictor of AKI. By Day 4 of treatment, 29% of treatment courses had supratherapeutic vancomycin exposure, with only 62% of courses achieving AUC24 targets. The identified toxicity threshold supports an AUC24 target range of 400–650 mg.h/L, assuming an MIC of 1 mg/L, to optimize vancomycin efficacy and minimize toxicity. This study highlights high rates of AKI in this population and emphasizes the importance of transitioning from trough‐based TDM to an AUC‐based approach to improve clinical outcomes.
Identification of a biomarker for Bacillus thuringiensis strains with high toxicity against Spodoptera frugiperda based on insecticidal gene linkage analysis
Authors: Xu Guoli , Wang Zeyu , Bai Yuqi , Crickmore Neil , Wang Kui , Hassen Ahmed Idris , Geng Lili , Shu Changlong , Zhang Jie
Published: June 2024

BACKGROUND

Bacillus thuringiensis (Bt) is a Gram‐positive bacterium that produces various insecticidal proteins used to control insect pests. Spodoptera frugiperda is a global insect pest which causes serious damage to crops, but bio‐insecticides currently available to control this pest have limited activity and so new ones are always being sought. In this study we have tested the hypothesis that a biomarker for strain toxicity could be found that would greatly facilitate the identification of new potential products.

RESULTS

Using genomic sequencing data we constructed a linkage network of insecticidal genes from 1957 Bt genomes and found that four gene families, namely cry1A, cry1I, cry2A and vip3A, showed strong linkage. For 95 strains isolated from soil samples we assayed them for toxicity towards S. frugiperda and for the presence of the above gene families. All of the strains that showed high toxicity also contained a member of the vip3A gene family. Two of them were more toxic than a commercially available strain and genomic sequencing identified a number of potentially novel toxin‐encoding genes.

CONCLUSIONS

The presence of a vip3A gene in the genome of a Bt strain proved to be a strong indicator of toxicity towards S. frugiperda validating this biomarker approach as a strategy for future discovery programs. © 2024 Society of Chemical Industry.
Role of varicocele repair in the era of assisted reproductive technologies: Lessons from 2000 cases of microsurgical varicocele repair
Authors: Shiraishi Koji
Published: June 2024

Backgrounds

In an era of advanced maternal age, there is less conclusive evidence regarding the treatment outcomes of varicocele repair for assisted reproductive technology (ART). Progress in basic research on varicocele is notable whereas there are many clinically relevant points to discuss.

Methods

Based on our experience with more than 2000 cases of microsurgical varicocele repair, we focused on the effectiveness of varicocele repair, pathophysiology, surgical approaches, contributions to ART, sperm DNA fragmentation, and varicocele‐associated azoospermia in this review with the aim of identifying clearer directions for basic and clinical research on varicocele.

Results

Microsurgical low ligation for varicocele repair is expected to remain the gold standard for surgical therapy. Based on the findings from a number of systematic reviews and meta‐analyses, negative opinions regarding the efficacy of microsurgical varicocele repair in male infertility treatment have become virtually nonexistent. However, the majority of evidence regarding surgical indications and effectiveness pertains to improvements in semen parameters or non‐ART pregnancy rates.

Conclusions

Further understandings regarding to pathophysiology of varicocele will likely be gained through comprehensive genetic, transcriptomic, and epigenetic analyses using blood and testicular samples from humans and we hope to develop new diagnostic methods and pharmacotherapy.
Alignment of the 2030 Agenda to the port industry
Authors: Tremblay David , Villeneuve Claude , Faubert Patrick
Published: June 2024

The United Nations' 2030 Agenda for Sustainable Development (2030 Agenda) serves as a global framework for addressing sustainability challenges. The port industry (PI) plays a crucial role in achieving the Sustainable Development Goals (SDGs) as a vital component of the global economy and supply chains. This research paper addresses the alignment between the PI and the 2030 Agenda. The study aims to bridge the research gap by exploring the extent to which the PI aligns with the SDGs and proposes a framework for implementation. Through an analysis of literature, this study identifies the relevant SDG targets for the PI. The original wordings of the relevant targets were adapted to make them meaningful to the PI. The adapted targets were validated by eight Canadian Port authorities to ensure their relevance and clarity. The alignment resulted in the identification of 69 targets, representing all 17 SDGs.
Bio‐Inspired Fluorescent Calcium Sulfate for the Conservation of Gypsum Plasterwork
Authors: Burgos‐Ruiz Miguel , Ilett Martha , Roncal‐Herrero Teresa , Elert Kerstin , Rubio‐Domene Ramon , Ruiz‐Agudo Encarnacion , Rodriguez‐Navarro Carlos
Published: June 2024

In this work, the potential of bio‐inspired strategies for the synthesis of calcium sulfate (CaSO4·nH2O) materials for heritage conservation is explored. For this, a nonclassical multi‐step crystallization mechanism to understand the effect of calcein– a fluorescent chelating agent with a high affinity for divalent cations— on the nucleation and growth of calcium sulfate phases is proposed. Moving from the nano‐ to the macro‐scale, this strategy sets the basis for the design and production of fluorescent nano‐bassanite (NB‐C; CaSO4·0.5H2O), with application as a fully compatible consolidant for the conservation of historic plasterwork. Once applied to gypsum (CaSO4·2H2O) plaster specimens, cementation upon hydration of nano‐bassanite results in a significant increase in mechanical strength, while intracrystalline occlusion of calcein in newly‐formed gypsum cement improves its weathering resistance. Furthermore, under UV irradiation, the luminescence produced by calcein molecules occluded in gypsum crystals formed upon nano‐bassanite hydration allows the easy identification of the newly deposited consolidant within the treated gypsum plaster without altering the substrate's appearance.
Zincophilic Nanospheres Assembled as Solid‐Electrolyte Interphase on Zn Metal Anodes for Reversible High‐rate Zn‐Ion Storage
Authors: Shao Hua , Zhang Xiaoyu , Zhou Yurong , Zhang Tianqi , Wang Xiaobo , Jiao Binglei , Xiao Wenxin , Feng Wei , Wang Xiaona , Di Jiangtao
Published: June 2024

Aqueous Zn‐ion batteries (ZIBs) are considered to be one of the most promising energy storage devices in the post‐lithium‐ion era with fast ionic conductivity, safety, and low cost. However, excessive accumulation of zinc dendrites will fracture and produce dead zinc, resulting in the unsatisfied utilization rate of Zn anodes, which greatly restricts the lifespan of the battery and reduces the reversibility. In this paper, by constructing a protective layer of ZnSnO3 hollow nanospheres in situ growth on the surface of the Zn anode, more zincophilic sites are established on the electrode surface. It demonstrates that uniform deposition of Zn ions by deepening the binding energy with Zn ion and its unique hollow structure shortens the diffusion distance of Zn ions and enhances the reaction kinetics. The assembled Zn‐ion hybrid supercapacitor (ZHSC) of ZnSnO3@Zn//AC achieved a long‐term lifespan with 4000 cycles at a current density of 10 mA cm−2 with a Coulombic efficiency of 99.31% and capacity retention of 79.6%. This work offers a new path for advanced Zn anodes interphase supporting the long cycle life with large capacities and improving electrochemical reversibility.
Recent Research on Iridium‐Based Electrocatalysts for Acidic Oxygen Evolution Reaction from the Origin of Reaction Mechanism
Authors: Chen Ligang , Zhao Wei , Zhang Juntao , Liu Min , Jia Yin , Wang Ruzhi , Chai Maorong
Published: June 2024

As the anode reaction of proton exchange membrane water electrolysis (PEMWE), the acidic oxygen evolution reaction (OER) is one of the main obstacles to the practical application of PEMWE due to its sluggish four‐electron transfer process. The development of high‐performance acidic OER electrocatalysts has become the key to improving the reaction kinetics. To date, although various excellent acidic OER electrocatalysts have been widely researched, Ir‐based nanomaterials are still state‐of‐the‐art electrocatalysts. Hence, a comprehensive and in‐depth understanding of the reaction mechanism of Ir‐based electrocatalysts is crucial for the precise optimization of catalytic performance. In this review, the origin and nature of the conventional adsorbate evolution mechanism (AEM) and the derived volcanic relationship on Ir‐based electrocatalysts for acidic OER processes are summarized and some optimization strategies for Ir‐based electrocatalysts based on the AEM are introduced. To further investigate the development strategy of high‐performance Ir‐based electrocatalysts, several unconventional OER mechanisms including dual‐site mechanism and lattice oxygen mediated mechanism, and their applications are introduced in detail. Thereafter, the active species on Ir‐based electrocatalysts at acidic OER are summarized and classified into surface Ir species and O species. Finally, the future development direction and prospect of Ir‐based electrocatalysts for acidic OER are put forward.
Computer vision‐based automated defect detection in ceramic bricks
Authors: Kataev M. Y. , Bulysheva L. A.
Published: June 2024

Nowadays, the development of cost‐effective, data‐driven technological processes using telecommunication technologies is essential. One of the focuses is on automating the process of evaluating the manufactured goods' quality. Vision‐based technology is now becoming increasingly used for monitoring purposes. Despite its advancements, computer vision technology has practical limitations. These include the physical characteristics of the measuring process, features specific to the technological procedures, and constraints related to software and mathematical algorithms. Among the cutting‐edge approaches, optical methods combined with neural network algorithms (NN) stand out. This significance is particularly evident because numerous industries continue to depend on manual defect identification methods, which are labour intensive, slow, and subject to human subjectivity. The article introduces a novel approach based on computer vision methods. It outlines an automated optical inspection system designed to detect defects in bricks on a transport belt during the production process. The article presents the processing algorithms used and discusses the results obtained.
Lagrange Multipliers Aided Modulated Model Predictive Control Technique for PMSM Drives
Authors: Huang Zhen , Wei Qiang , Wu Tingfeng , Xia Yonghong
Published: June 2024

The modulated model predictive control (MMPC) method utilizes multiple voltage vectors in sequence within one switching cycle, achieving a fixed switching frequency. However, the control performance of using the MMPC technique still suffers from imprecise vector duration derivation and high computational burden. To address this, this paper proposes an improved MMPC technique aided by the Lagrange multiplier method to accurately calculate the duration of each vector, and then efficiently select the optimal voltage vector. Compared to the existing MMPC techniques, the proposed one exhibits a lower computational burden and superior steady‐state performance. Those benefits have been proven by the experimental results of a 1.5 k rpm permanent magnet synchronous motor drive. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.
Effect of solid lubricant additives on solid particle erosion characteristics of rigid and toughened epoxy resins
Authors: Özzaim Toker Pelin , Korkusuz Orkan Baran , Ozun Elanur , Ceylan Reyhan , Fidan Sinan , Yarar Eser , Bora Mustafa Özgür , Sınmazçelik Tamer
Published: June 2024

Solid lubricants are added to polymers to upgrade their tribological properties, especially in cases where adhesive and abrasive friction are valid. However, there are not enough studies on the effects of solid lubricants on particle erosion. This study investigated the effects on solid particle erosion behavior of three different well known solid lubricants (molybdenum disulfide, polytetrafluoroethylene, and graphite). These solid lubricants were added at three different ratios (5, 10, and 15 wt.%) to the two different type (rigid and toughened) epoxy resins. Garnet abrasive particles (180–400 μm) were blasted to the sample surface under 1.5 bar for 15 s to conduct solid particle erosion tests. The erosive wear mechanisms of neat and solid lubricant‐reinforced epoxy resins were investigated in relation to the epoxy type, solid lubricant type, and solid lubricant reinforcement ratio. Statistical analysis was performed according to response surface methodology to support the experimental results, and ANOVA tables were obtained. The wear and deformations that occurred on the surface after solid particle erosion were examined using a noncontact optical profilometer system and scanning electron microscopy, and a significant relationship was detected between the deformation on the surface and particle erosion. Analysis results showed that the factor causing the greatest erosion rate change was the epoxy resin type. Finally, it has been observed that all solid lubricants reduce the erosive wear resistance, and this resistance decreases as the weight ratio increases.

Highlights

Investigations were conducted into the erosion behavior of two types of epoxy resins: rigid and toughened. The toughened epoxy resin exhibited greater resistance to erosion. Although it has the same type of content, on average, rigid epoxy worn 2–4 times more than toughened epoxy.

The effect of adding polytetrafluoroethylene tended to increase the erosion rate of both rigid and toughened epoxy resin less than that of other solid lubricants.

Graphite particles increased the erosion rate of toughened epoxy by 1.5–3 times and that of rigid epoxy by 2–3 times, depending on the value of the reinforcement ratio.

MoS2 increased the erosion rate of toughened epoxy by 1.5–3 times and that of rigid epoxy by 2–3 times.

Using a noncontact optical profilometer (for investigating surface topography), it was proven that there is a significant relationship between the erosion rate and roughness characteristics. Wear mechanisms were identified by SEM analysis.
Rigid-Flexible Coupling Dynamics Analysis of Boom-Hoisting System of Wind Power Crane
Authors: Cao Xuyang , Xu Guoyang , Hu Yongchang , Zhou Jihong , Kang Jian
Published: June 2024

Based on the slenderness of wind power crane boom and the complexity of working environment, a mathematical model of rigid-flexible coupling dynamics including wind load and vibration characteristic analysis is carried out for the boom-hoisting system. The equivalent spring-damping system, spatial pendulum system and elastic double-force rod are used to simulate the elastic vibration of boom, the swing of lifting weight and the elastic vibration of wire rope, respectively. The kinematic characteristics of each component are described using a hybrid coordinate system. Simulation of wind loads through an instantaneous wind model consisting of the average and pulsating wind. Derivation of dynamic model for wind power crane under wind load based on the Lagrange equation. Taking a certain type of wind power crane as the research object, based on the derived mathematical model and ADAMS model, the response curves of boom and lifting weight are solved in MATLAB and ADAMS respectively for the rotary working condition, to verify the rationality and accuracy of the mathematical model and to obtain the influence of wind load on the swing angle of lifting weight. The analysis results provide a certain theoretical basis for crane structure design, control system design and wind turbine hoisting.
Analysis on Random Vibration and Impact Response of Vehicle-Borne Electronic Chassis
Authors: Zhu Zenghui , Meng Qingqin
Published: June 2024

In order to meet lightweight design requirement of vehicle-borne electronic chassis, vibration and impact response of chassis was analyzed based on the theory of random vibration and transient impact dynamics. Considering the influence of heat dissipation, corrosion resistance, material strength and economy of processing, weight reduction design was carried out according to vibration and impact response stress nephogram of chassis. The computation results show that the weight of chassis frame decreased by 16.4% and the first-order modal frequency of chassis decreased by 14.2% after weight reduction. Impact response had a lag relative to input impact spectrum. The increase of vibration stress was obviously higher than that of impact stress in different directions, which was still less than the corresponding material yield strength. That is, the structural strength of chassis after weight reduction meets the requirements of vibration and impact resistant design. The research results can provide theoretical basis of electronic equipment lightweight design under vehicle vibration and impact environment.
Design Method of Rail Grinding Profile Based on Wheel Rail Contact Relationship
Authors: Song Rui , Chen Dilai , Shen Gang
Published: June 2024

When the railway track is damaged, it is essential to grind it in in a timely manner to enhance the wheel-rail contact performance. This paper relies primarily on the rolling radius difference function as the main design basis, taking the expected distribution between the wheel and the rail as the boundary condition. In cases where the abscissa of the rail is known, the Euler method is used to solve the differential equation to obtain the optimized ordinate of the rail. The profile of the rail is optimized, and the feasibility of the design method is verified through programmed algorithm. Based on the application results of the rail grinding profile design on the Wuhan-Guangzhou line, the rail light strip position and contact point distribution are more reasonable after grinding, the dynamic performance of the vehicle passing is improved, and the wheel-rail wear rate is reduced.
Parameter Optimization Methods of the Hydraulic Regenerative Braking System Based on the Actual Working Condition
Authors: Luo Tingting , Luo Nianning , Yang Jing , Huang Bo
Published: June 2024

Hydraulic regenerative braking system is a kind of complex MIMO (Multiple Input Multiple Output) system which is strongly nonlinear and multivariable, especially affected observably by the working condition. Moreover, it possesses the typical hybrid system characteristics since there are a multitude of nonlinear components internal which should result to continuous dynamic variation and discrete decision process. Hence, the traditional calculating method is difficult to analyze and evaluate the system accurately while operating on the actual working conditions. In order to solve the parameters optimization problem of the system which has significantly hybrid system characteristics constrained by the actual working conditions, this paper presents a new type of genetic algorithm by solving fitness function based on operation simulation, which provides a promising full condition optimization method for parameter optimization according to this kind of system. Simulation results show that this algorithm could optimize system configuration and enhance 3% for the braking energy recovery efficiency.
Design and Development of Dynamic Test Bench for Electric Wheel Load Sensing Suspension
Authors: Li Yan , Sun Pengbo , Chen Jiawei , Chen Xinbo
Published: June 2024

Based on the modular design idea, a new type of dynamic test bench for electric wheel load sensing suspension was designed and developed, including load-bearing platform module, vertical force loading module, electric wheel module, spring mass simulation module, etc., and the test bench has the functions of wheel jump simulation, steering simulation and wheel vertical force and lateral force detection. The finite element simulation results show that the strength of the test bench meets the requirements. The results of the virtual prototype simulation show that the test bench can accurately measure the vertical and lateral forces experienced during the dynamic operation of the wheels.
Simulation and Analysis of the Internal Flow Field of Mining Solenoid Pilot Valve Based on Fluent
Authors: Wang Zhaoqiang , Zhu Lijing , Guo Lei , Lu Yangjun , Li Peixing , Lu Chenhun
Published: June 2024

During the commutation process, the electromagnetic pilot valve experiences turbulent kinetic energy dissipation, leading to unstable internal flow and generating noise in the valve. Based on computational fluid dynamics (CFD), the phenomena of impact and energy consumption in a new type of high-pressure and high-speed electromagnetic pilot valve were investigated. Then flow field simulations were conducted under various differential pressure and valve opening conditions, in order to obtain distribution maps of turbulent kinetic energy, pressure, and velocity. Finally, the simulation results were compared, and the results showed that increasing the outlet pressure and enlarging the valve port opening have a positive impact on mitigating the structural issues in the pilot valve.
Research on EMC Simulation of Electric Drive System of Electric Engineering Machinery
Authors: Ming Qiaohong , Wang Yangyang , Zong Meiyu
Published: June 2024

In order to suppress the electromagnetic interference in electric construction machinery, improve the stability and safety of the vehicle on the influence factors of electric construction machinery EMC system analysis, electric drive system due to the internal power electronic equipment for a long time in the high voltage, high current conditions and become the main influence factors of electric construction machinery EMC. The main methods to reduce electromagnetic interference of electric drive system grounding, shielding and filtering are expounded, which leads to the emulated research of EMC simulation of electric drive system of electric engineering machinery. The equivalent circuit model of battery, electronic control, motor and test system is established, and the low-pass filter composed of inductor and capacitor is designed. And the combined three electric system, test system, filter circuit composed of the model of simulation analysis, with or without filter input current, different frequencies of input and output voltage signals compared, the results show that adding filter can effectively improve the conducted interference, the use of RLC filter composed of four RLC components, can effectively improve the signal low frequency bias and high frequency distortion.
Reliability Optimization Design Method for Firearms Automaton Mechanism
Authors: Fang Yichuan , Wang Yongjuan , Li Pengchao , Gu Tongguang , Gao Xin’an
Published: June 2024

In order to deal with the reliability optimization design problem of mechanisms containing multiple motion phases and multiple collisions, this paper takes the firearms automaton as an example and gives a general method to deal with such problems. Firstly, the motion stages are divided according to the automatic cycle diagram of the firearms automaton, and the discrete dynamics model of the firearms is established. Then the reliability model of the automaton mechanism is established based on the performance margin theory. Finally, taking the pressure coefficient of air chamber, the friction coefficient of the guide, the stiffness of the counter-recoil spring and the stiffness of the hammer spring as design variables, the optimized design variables are obtained through the calculation of the sequential quadratic programming (SQP) algorithm. The results of the optimized design are close to the idealized results of the existing products, which proves the rationality and effectiveness of the mechanism reliability optimization design method proposed in this paper.
Study on Kinetic Energy Conversion of Perforating Shaped Charge Jet in Perforating Completion
Authors: Li Zhenxiang , Yuan Fayong , Guo Ruifeng , Chen Zhihang , Zhang Zhengjin
Published: June 2024

The energy of a perforating shaped charge is the cause of transient pressure fluctuations in a wellbore. Based on the law of energy conservation, the energy can be divided into the kinetic energy of a jet, the residual energy of a wellbore, and energy dissipation. The jet kinetic energy is used to penetrate a perforating gun, casing, and formation. The residual energy of a wellbore is used to cause wellbore pressure fluctuations. Based on the fluid–structure coupling principle, a jet penetration model was developed to improve the conversion rate of the jet kinetic energy, reduce the residual energy of a wellbore, protect wellbore safety, and reduce the downhole perforating completion accident. This model took into account a penetrating charge shell, explosive, liner, perforating gun, and casing. Meanwhile, the penetration process and kinetic energy conversion of a perforating shaped charge jet were studied. The obtained results indicated that the kinetic energy conversion of a perforating shaped charge jet is significantly affected by the cone angle of a liner, the thickness of a liner, and explosive mass. The 70°cone angle of a liner, its 1 mm thickness, and the 25 g explosive mass have the maximum kinetic energy conversion in the research range.
Research on the Design and Verification Process of Mechanical Penetrations in Reactor Compartment
Authors: Zhang Qian , Qian Zuoqin , Wang Qiang , Wang Xinyu
Published: June 2024

Mechanical penetrations, as important pressure pipelines penetrating the reactor compartment, withstand high temperatures and pressures. The current complete design and verification process for mechanical penetrations. This article focuses on the problem of stress concentration and easy damage of the penetration components in the reactor compartment under high temperature and high pressure environment. Combining with the existing regulations of nuclear power plants and ships, finite element analysis method is used to analyze the stress of the penetration components under specific high temperature and high pressure and ship ultimate load coupling. At the same time, based on the simulation analysis results, the structural dimensions of the penetration components are optimized, and a mechanical penetration verification process is designed. The coupled thermal stress results of the penetration indicate that the stress of the penetration is too large at the tail of the sleeve, with the values of primary film stress Pm and primary bending stress Pb being 228.2 and 275.91 MPa, respectively. From this, it can be seemed that there is obvious stress concentration at the junction of the support ring and sleeve, as well as at the transition point of the insulation layer, which is the weakest area of the penetration.
Algorithm Design of a Variable Height Wheel-Legged Robot with Fuzzy Theory and PID Fusion Control
Authors: Cao Xuyang , Pu Changlin
Published: June 2024

A balancing control algorithm for a wheel-legged robot is designed for current logistics and distribution mobile robots. Since the wheel-legged robot is a nonlinear underactuated system, it is crucial to realize the balanced control and robustness of the wheel-legged robot in the absence of an accurate dynamics model. In this paper, an optimal control scheme for the wheel-legged robot based on the fusion control of variable-height adaptive fuzzy PID and conventional PID is designed. The balance of the wheel-legged robot is controlled by adaptive fuzzy PID control, the lifting and attitude changes of the two sides of the wheel-legs are controlled with high precision by traditional PID control, and the speed and steering control of the wheel-legged robot is not affected by the structure of the model, and is controlled by traditional PID control with linearization. The attitude of the robot is detected in real time using the BMI088 attitude sensor to realize the positional control. Experimental and simulation results show that the control algorithm of the wheel-legged robot designed in this paper is reliable, and the robot runs smoothly and robustly.
A Machine-Vision-Based Hub Location Detection Technique for Installing Wind Turbines
Authors: Cao Xuyang , Hu Yongchang , Xu Guoyang , Song Shuai , Tie Xiaochun
Published: June 2024

A position detection approach based on machine vision is developed to address the issue that the traditional wind turbine hub lifting procedure relies on the location of engineers and cannot provide quick feedback on the position information. A camera and a range sensor are mounted on the suspended object to enable real-time detection of the fan hub’s posture state in relation to the engine room. A monocular camera positioning technique based on circular features is created for this detection method. The relative pose coordinates of the hub are computed using the position data given by the range sensor. A filter for the range sensor is created based on the hoisting features of the actual working circumstances. The filter applies a filter to the data from the ranging sensor, considerably reducing measurement error and enhancing detection technique stability.
Adaptive Control of Drilling Rig Power Head Speed
Authors: Xu Xinxin , Cai Wanzhi
Published: June 2024

In the drilling process, the adjustment of drill pipe rotational speed is essential to accommodate the variations encountered in different geological strata. However, the existing low automation level in drilling rigs and heavy operator reliance often result in suboptimal speed regulation, leading to low drilling efficiency. An adaptive control approach for power head speed based on a fuzzy clustering algorithm was proposed, which utilizes the fuzzy clustering algorithm (FCM) to cluster drilling parameters, including drilling pressure, rotational speed, and drilling speed, to identify of distinct strata. Furthermore, the rotational speeds of the clustering centers of different strata were used as the input rotational speeds of its control system, the simulation results show that the speed control can be realized by controlling the opening of the valve port, and the fuzzy PID control is used to realize the adaptive control of the speed and the tracking of the speed curve.
Fluctuation of Near-Wall Pressure During the Cavitation Bubble Collapse
Authors: Yuan Zhicheng , Li Haowen , Yang Meng , Bian Yongming , Chen Li
Published: June 2024

Cavitation bubble collapse, which generates strong shock waves and high-velocity liquid jets, is responsible for the erosive damage to hydraulic components. In order to assess the fluctuation of near-wall pressure, in this work, an open-source package OpenFOAM is utilized for solving the Navier–Stokes equation. To track the liquid–air interface, the volume of fluid (VoF) method-based compressibleInterFoam solver is selected, and its shipped dynamic contact angle model is modified to obtain better accuracy when considering the wettability of substrates. Numerical methods are first validated by comparing with experiment, and then it is extended to study the effect of bubble diameter, pressure difference, and surface wettability on the fluctuation of near-wall pressure. Simulation results show that the initial sphere bubble goes through three stages of growth, shrinkage, and collapse near the wall. A larger bubble size leads to higher impact pressure due to the higher speed of the liquid jet. The difference in initial pressure in and out of the bubble has a great effect on the collapse behaviour. In addition, a hydrophobic surface, meaning hard liquid pining, can speed up the damping of near wall pressure. The findings in this work will be a guide to designing hydraulic components for limiting the erosive damages of cavitation bubble collapse.
Research on Autonomous Operation Motion Control of Excavator
Authors: Gong Mingde , Jin Zhong , Zhang Yue , Liu Wenbin , Ning Yue
Published: June 2024

Accurate motion control is the premise for the unmanned excavator to complete the operation. In this paper, the motion control of a 22 t hydraulic excavator is studied. By establishing the dynamic model of the 4-degree-of-freedom excavator working device, the external interference caused by gravity, centripetal force, Coriolis force and inertia to the hydraulic cylinder is compensated. The bucket load and related parameters in the excavation process are identified online, and the motion control accuracy of the excavator is improved. Based on the dynamic model, the motion control method of the unmanned excavator is given. The simulation and experimental results show that this motion control strategy can effectively improve the autonomous operation accuracy of the excavator.
Analysis and Experiment Study About Vibration Compaction Based on Drucker-Prager Model
Authors: Ma Liying , Gui Macheng , Gui Shaoxiong , Cao Yuanwen
Published: June 2024

The relationship and the applicable conditions between Mohr–Coulomb model and linear Drucker-Prager model were discussed, and the results showed that when the friction angle was less than 22° Drucker-Prager model was more suitable for modelling the soil unit; When the friction angle was more than 22°, the Mohr–Coulomb model should be used. In order to further study the compaction characteristics of vibratory roller and the dynamic relationship between vibratory roller and soil, the finite element model of “vibrating roller-soil” was established. The simulation results showed that vertical stress of the soil distributed symmetrically along the axial direction of the vibrating drum, shift forward along the direction of the vibration drum, and decreased sharply with the increasement of the depth. Then experiments carried out showed that acceleration of the vibrating drum was positively correlated with the compaction times, which verified the model was basically correct. Moreover, the regression equation between the compaction degree and the effective value of acceleration was obtained, which provided the idea for the new compaction degree monitoring system.
Multi-mode Sliding Mode Control of Four-Cable Parallel Robot Based on Wind Disturbance Observation
Authors: Tong Shenghao , Zhao Long , Shi Huaitao , Duo Zhiqiang , He Cai
Published: June 2024

Aiming at the problem of accurate trajectory tracking of four-cable parallel robot under wind disturbance in the process of material handling in buildings, a multi-mode sliding mode control (MSMC) method based on wind disturbance observer is proposed. Firstly, the wind field model is established, and the comprehensive wind speed model is introduced into the accurate dynamic model as a wind disturbance factor. Secondly, the wind disturbance observer is introduced to estimate the total disturbance of wind disturbance error in real time, which effectively reduces the switching gain, thus effectively reducing the vibration and improving the control accuracy of the system. Combined with the dynamic performance of multimode sliding mode controller, it can be switched at will to reduce chattering. Compared with the traditional sliding mode control method SMC, the anti-interference ability of MSMC is verified. The results show that the designed multimode sliding mode controller can effectively suppress the influence of wind disturbance on the vibration of the end effector.
Development of CDC Shock Absorber Design Software
Authors: Liang Zhitao , Zhao Zhiwei , Yue Luyou , Yang Xinlong , Zhang Xinxing , Zhang Bing
Published: June 2024

In response to the low design efficiency caused by the numerous design parameters of existing shock absorbers, this research presents the design of an efficient software tool for obtaining the external characteristics of Continuous Damping Control (CDC) shock absorbers. Firstly, a mathematical model for the damping force of the shock absorber was established based on principles from fluid dynamics, elasticity mechanics, and throttle orifice models in the rebound and compression valve systems. Secondly, a Graphical User Interface (GUI) was developed to visualize the external characteristics and conduct simulation studies of the CDC shock absorber. Finally, experiments were performed on a shock absorber test bench to validate the external characteristics of the CDC shock absorber using initial structural parameters. The GUI software interface enables direct adjustment of the shock absorber's structural parameters and signal excitation, thereby enhancing the practical efficiency of the shock absorber. A comparison between simulation and experimental results reveals that the relative error rate is generally high when the velocity amplitude is 0.052m/s, with a maximum relative error rate of 24.44%. For other excitation velocity amplitudes, the relative error rate remains within 10%. This demonstrates the high accuracy and reliability of the established mathematical model for the CDC shock absorber, providing a solid theoretical foundation for studying the shock absorber's external characteristics.