bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Application of Feedback Linearizing Controller with Disturbance Observer for DC Motor Real-Time Speed Control
Authors: Prasanthi Achikkulath , Shareef Hussain , Asna Madathodika 
Published: January 2024

Abstract
The main objective of this paper is the hardware implementation of robust speed and torque control of DC motors. The proposed speed controller is a feedback linearizing controller (FLC) with a disturbance observer (DO). The designed control circuit can withstand non-linearities of the system and other unpredictable disturbances. In addition, the exact mathematical modelling of the controller is used and thus the system can be easily reproduced to any higher rating. The converter used to interface the DC motor is a bi-directional H bridge converter that can supply and accept power at any voltage conditions. The developed system is experimentally tested under different case studies of motoring and regenerating conditions. From the results, it is verified that the objective is met, and the designed prototype system can work accurately to follow the speed and load torque. The designed system can be used for variety of industrial applications including electric traction, robotics, and various fixed as well as variable speed electric drives.
Investigation of the technical potential of a hydrogen powered phosphoric acid fuel cell (PAFC) for CHP
Authors: Biebl M , Roes J , Hoster H 
Published: January 2024

Abstract
Due to the fluctuating feed-in of renewable energies, controllable power plants such as highly efficient CHP plants (combined heat and power) will continue to be required to cover the residual load. Gas engines and turbines currently dominate the natural gas-based CHP market due to their low investment costs and acceptable electrical efficiency. In the event of a future fuel switch due to the energy transition from natural gas to hydrogen, fuel cell systems are becoming increasingly important due to their very high efficiency and improved dynamics in hydrogen operation and can therefore represent an alternative to gas engines and turbines. In addition to a possible fuel switch, good dynamic and full heat utilization represents an additional challenge for CHP systems. Therefore, this study aims to investigate the influence of a fuel switch from natural gas to hydrogen on the operation of a fuel cell (PAFC) in terms of efficiency, heat utilization and dynamics. It was shown that the electrical efficiency of the hydrogen-operated PAFC is significantly higher than in natural gas operation due to the omitted reformer and the associated reformer losses. In hydrogen operation, there is also no limitation of the dynamics by the reformer. Furthermore, in hydrogen operation there is a more favorable ratio of high-temperature to low-temperature heat, which facilitates the use of heat. Detailed and validated simulation models in Aspen Plus are used as the basis for this investigation.
Design and simulation analysis of 130 KWp grid-connected solar PV system using PVsyst: A case study in Egypt.
Authors: Moustafa M. , Mahmoud M. , Akef S. , Swillam M. 
Published: January 2024

Abstract
This paper presents a feasibility study using a PV system grid-connected photovoltaic design that satisfies a 130 KWp grid’s electrical needs for a local factory in Al Obour City, Egypt (Coordinates 30.19373, 31.44213). This system has been mounted on a fixed tilt mounting structure. The system comprises a photovoltaic array to capture solar energy. The modeling is accomplished by evaluating the required load and selecting and deciding the proper specifications of the components inherent in the system. Several constituents, such as the geographic area, atmospheric condition, solar irradiance, and load consumption, are analyzed and discussed for the whole work. The system produces 212.7 MWh each year. The cost of the system can be enhanced by variable system parameters such as net present one, initial capital one, energy cost, and operating expense. Further, the techno-economic analysis of the suggested system has been performed using PVsyst simulation software. The simulated results reveal that the proposed model meets the load demand, reducing the monthly bill by ~20 %. The PVsyst proves an easy, speedy, accurate, dependable, well-grounded software tool for the simulation of the solar PV system.
Failure analysis of low-pressure steam superheater in a purification device
Authors: Song Ce , Li Xiaowei , Din Zhihui , Zhu Zhengwei , Du Chenyang 
Published: January 2024

Abstract
For a coal chemical enterprise purification unit in the low-pressure steam superheater in the use of frequent occurrence of heat exchanger tube bundle cracking, to find the cause of failure and ensure the safe and stable continuous operation of the device, the failure analysis work shall be carried out. In this paper, we have examined the cracked heat exchanger tube bundle in terms of macroscopic inspection, material chemical composition analysis, mechanical properties analysis scanning electron microscopy analysis, corrosion product analysis, metallurgical analysis, and many other tests, and also analyzed the internal and external media of the tube bundle, ultimately concluding the main reason for cracking of heat exchanger tube bundle for the alkali stress corrosion cracking. At the same time, to avoid similar problems, we hope that the failure analysis of the use and maintenance, inspection, and testing of the equipment provides a good solution to the failure of the equipment, and provides the best solution to the problem. It is hoped that this failure analysis will provide valuable experience for the use and maintenance of this type of equipment.
Failure analysis of large and complex engine blades based on experimental research
Authors: Chen Li , Feng Yanpeng , Ding Keqin 
Published: January 2024

Abstract
On a certain day in December 2022, a GE90 engine equipped by an airline experienced a surge during flight. Ground inspection revealed broken blades of the 9-stage high-pressure compressor. To identify the cause of its fracture failure, the macroscopic fracture surface was first analyzed. Obvious fatigue crack propagation characteristics were found at the blade cross-section. Small pits formed by the impact were observed at the crack source location, indicating that the blade was first formed into a circular arc-shaped impact wound after being impacted by an external object. In the subsequent service process, under continuous vibration, fatigue cracks are formed at the impact point as the crack source and gradually propagate, ultimately leading to blade fracture and failure. To further explore the source of foreign objects causing impact damage, the surface scanning method using energy spectrum analysis was used. An enriched region of C element was found near the impact point. However, due to the lack of conditions for the formation of C combustion products at the compressor location, it can be considered that the foreign object may have come from external sources.
Experimental study on stress relaxation of rubber O-ring for mechanical seal
Authors: Jin Liang , Che Liangda 
Published: January 2024

Abstract
The stress relaxation process and its variation law under multiple stresses have an important impact on the performance of rubber O-rings. An O-ring experimental device was developed, the end contact forces of the O-ring under the conditions of the single and multiple stresses were tested, and the contact force retention rate was calculated based on the test results. The change processes and laws of the end face contact force and the retention rate were obtained by the analyses of the experimental data under the different impact factors. The experimental results indicated that the compression ratio of the O-ring can increase the end contact force, but the greater compression ratio results in greater attenuation of contact force and longer attenuation time. The medium temperature hurts the contact force retention rate, and the medium pressure is conducive to stabilizing the contact force retention rate.
Research of influencing factors on tripping speed of double plungers turbine overspeed protector
Authors: Jiang Haicheng , Wang Decheng , Cheng Peng , Shao Chenxi , Zhang Jianghong , Jiao Hongchao 
Published: January 2024

Abstract
The over-speed protection mechanism is very important for the safe operation of the steam turbine, but in actual production, the tripping speed often fluctuates and deviates from the set value, resulting in a decrease in the reliability of the unit operation. In this paper, the factors that affect the tripping speed of double plungers turbine overspeed protection mechanism are analysed, the mechanism of mechanical vibration and friction that cause the tripping speed to fluctuate is explored through theoretical calculation and simulation analysis, and the change of spring dynamic stiffness by using the dynamic stiffness matrix method and finite element simulation is analysed. The change of friction force under different contact modes is calculated by using the L-N contact force model and the modified Coulomb friction model, and the change of tripping speed under non-ideal friction conditions is explored through dynamic simulation.
Trajectory prediction-based guidance law
Authors: Li Mengxuan , Guo Jianguo , Jiang Ruimin 
Published: January 2024

Abstract
This paper proposes a guidance law based on trajectory prediction, aiming to address the difficulty of traditional guidance laws in meeting high-speed and highly maneuverable vehicles. The unscented Kalman filtering (UKF) technique is employed to estimate the target’s motion and predict the virtual impact point using the Singer model and measuring model. The midcourse guidance law is applied to the virtual target, taking into account the constraint of the intersection angle, while the terminal guidance utilizes modified proportional guidance. To mitigate the overload chattering in the transition sections of both midcourse and terminal guidance, the distance is used to modify the transition section of the terminal guidance. Simulation results demonstrate that the proposed guidance law effectively reduces both the encounter angle and the required maneuvering. Furthermore, to minimize midcourse guidance errors, the prediction results of the virtual target are continually updated during the trace process. This method can also be applied to trail other highly maneuverable targets.
Design and realization of a small launch system with autonomous regulation and recognition guidance
Authors: Wang Huanzhen , Sun Haozhe , Wang Shengsong , Liang Keshan 
Published: January 2024

Abstract
A small launching system with autonomous regulation and recognition guidance is designed. Firstly, it ensures a solid and reliable transmission on the mechanical structure of the launcher and the small vehicle. Further, stepper motors and sensors are used to ensure precise control and effective feedback of the angle of the launcher. The small vehicle is equipped with the functions of guidance signal recognition and attitude adjustment, which have the advantages of strong real-time and high versatility. Finally, the practicality and accuracy of the designed launching system to a certain extent are verified through tests.
A study on flow distribution characteristics of heat exchanger module integration scheme for aircraft environmental control system based on CFD
Authors: Zhong Yifei , Wu Chang , Luo Haining , Zeng Yu 
Published: January 2024

Abstract
With the rapid development of the civil aviation industry, the performance requirements of the environmental control system for domestic commercial large aircraft are gradually improved, and the ram air inlet heat exchanger system is its main component. Generally speaking, a ram air heat exchanger system mainly includes an air conditioning system heat exchanger, air preparation system heat exchanger, and auxiliary cooling system heat exchanger. The integration mode of the heat exchanger will directly affect the flow and flow distribution characteristics of the ram air heat exchanger system. This paper develops three integration schemes referring to the integration mode of heat exchangers in Boeing 787 and Airbus 350 aircraft. Based on Fluent software, the calculation and simulation of three integrated scheme models under the seven working conditions of taking off, climbing, cruising, descent, hovering, emergency, and landing during flight were carried out, and the flow distribution and flow resistance values of different schemes were obtained, which were compared to meet the heat transfer requirements.
Thermal field simulation and material parameter optimization for spaceborne annular truss antennas
Authors: Fu Xiaoyi , Hua Yuntao , Ma Wenlai , Cui Hutao , Zhao Yang 
Published: January 2024

Abstract
The operational efficacy of large spaceborne annular truss antennas in orbit is significantly influenced by solar irradiation and alternating Earth shadow. This antenna system periodically encounters diverse extreme environments that impact the precision of the antenna surface performance. Consequently, this study presents an optimized thermal control design and conducts temperature field simulation calculations for such antennas. Initial efforts are directed toward analyzing the variables influencing the antenna structure’s temperature, with specific attention paid to the distinctive compositional characteristics of high-precision antennas. As a subsequent step, orthogonal tests are implemented, facilitating the development of an antenna thermal analysis model. This model assists in the identification of principal variables influencing the antenna’s temperature field. Finally, the antenna’s optimal thermal design is drawn upon the biogeography-based optimization (BBO) algorithm, enabling the derivation of ideal material parameters for the thermal design of the antenna. This methodology offers theoretical guidance for future thermal control design of large spaceborne annular truss antennas.
Study on effect of injection temperature on shear strength of the direct bond between polyphenylene sulfide and anodized aluminum alloy
Authors: Zhao Wei , Qiu Jianhui , Sakai Eiichi , Wu Haonan , Feng Huixia 
Published: January 2024

Abstract
A simple and environmentally friendly technique has been proposed to form a composite structure of high interfacial bonding strength between polyphenylene sulfide (PPS) and aluminum alloy (Al). The Al substrate is modified through anodization and enlarging treatments. The influences of injection temperature on the anodic aluminum oxide film surface on the interfacial bond strength of the formed PPS-Al is discussed. The results revealed that when the injection temperature of PPS was set at 310°C, the bonding strength increased to 18.0 MPa. The adhesive strength exhibits a clear dependency on the injection temperature. At higher injection temperatures, PPS exhibits higher flowability and better penetration into nanoscale pores, resulting in a strong interlocking between PPS and anodized aluminum alloy.
High -temperature duct thermal insulation debonding analysis for civil aircraft
Authors: Du Nannan 
Published: January 2024

Abstract
The paper focuses on the problem of the composite thermal insulation of High-temperature Pneumatic ducts for civil aircraft debonding phenomenon. The performance of thermal insulation material is tested to explain the reason why debonding. A model based on the test and thermal kinetic analysis is proposed to quantify the life of the insulation. Based on the model, a certain duration of thermal insulation is calculated. This methodology can predict the life of thermal insulation.
Experimental study on the combustion characteristics of carbon fiber composite materials coated in different coatings
Authors: Yao Shuai , Dong Lihui , Zheng Qiuyu , Liu Fangbo , Zhao Yingwen , Yuan Ruijie , Tang Mingjun 
Published: January 2024

Abstract
The special environment in which the aircraft operates in terms of flight and safety assurance has special requirements for coating performance. Based on the combustion characteristics of four kinds of high-performance aviation coatings coated with carbon fiber composites, for parameters such as average ignition time and heat release rate of the composite, the results show that the carbon fiber composite has the longest average ignition time, Minimum heat release rate, while the 2-ethyl-4-Mylimidazole cured epoxy coated fiber composite had the shortest average ignition time. The maximum heat release rate was observed.
Study on microstructure and corrosion resistance of CoCrFeNiTi0.2Mox high entropy alloy
Authors: Chen Shujun , Zhao Hui , Yang Jingmei , Li Mei 
Published: January 2024

Abstract
Vacuum arc melting was employed by produting the high entropy alloys CoCrFeNiTi0.2Mox (x=0, 0.1, 0.3). We investigated the influence of Mo on the phase, microstructure, and corrosion resistance of CoCrFeNiTi0.2Mox (x=0, 0.1, 0.3). The introduction of Mo led the high entropy alloy to shift to a double-phase structure, with a rise in the volume percentage of σ phase. The corrosion resistance of high-entropy alloys decreases first and subsequently increases with increasing Mo content in 3.5 weight percent NaCl solution.
Methods of machine learning for the analysis of cosmic rays mass composition with the KASCADE experiment data
Authors: Kuznetsov M.Y. , Petrov N.A. , Plokhikh I.A. , Sotnikov V.V. 
Published: January 2024

Abstract
We study the problem of reconstruction of high-energy cosmic rays mass composition from the experimental data of extensive air showers. We develop several machine learning methods for the reconstruction of energy spectra of separate primary nuclei at energies 1–100 PeV, using the public data and Monte-Carlo simulations of the KASCADE experiment from the KCDC platform. We estimate the uncertainties of our methods, including the unfolding procedure, and show that the overall accuracy exceeds that of the method used in the original studies of the KASCADE experiment.
Optimal geometry of the powered roof support’s operation
Authors: Trzop K , Szurgacz D 
Published: January 2024

Abstract
Monitoring the working parameters of powered roof support is an area for improvement in hard coal mining. The phenomena occurring during the operation generate many risks from difficult geological and mining conditions, leading to undesirable events. In addition, improper use of machinery and equipment results in a high accident rate in mining. Thus, monitoring the operation of machines in mining reduces accidents and losses resulting from stops and prevents unforeseen failures caused by operational and external factors. The paper presents the research results on the optimal geometry of the powered roof support operation in the mining wall. The research included the powered roof support’s essential elements’ operation. Sensors constituting the measuring system were installed on these elements. The measurements made by the sensors made it possible to determine the working height at a given stage of the section’s operation. The research was carried out in three sections, which were part of the powered roof support. The measurements were taken during actual changes occurring in the coal mining process.
Preliminary Assessment of Badajo Cave (Segovia, Spain) Stability Using Empirical, Numerical and Remote Techniques
Authors: Benrabah A , Domínguez S Senent , Bordehore L Jorda , Alonzo D Alvares , Herrero A Diez , Herrero M de Andrés 
Published: January 2024

Abstract
Badajo cave is a shallow cavity (hemispherical rock shelter) located in the valley of Clamores River (Segovia city, Central Spain). This small canyon carved in Cretaceous dolostones has numerous geosites, as well as a rich archaeological and historical heritage. There are dozens of rock outcrops in the valley’s cliffs and slopes, on both banks, where various types of sedimentary rocks can be easily recognized and differentiated, especially carbonates (dolostones and limestones), and mixed carbonate-detrital (dolomitic sandstones, calcareous silts, marls). The cave was formed by karstic and gravitational processes within a mixed dolomitic sandstones and limestones, and it has an important archaeological interest. This study proposes a preliminary stability analyses of the cave applying: (i) empirical approaches based on geomechanical classifications using Barton’s Q Index, Rock Mass Rating (RMR) and the recently created Cave Geomechanical Index (CGI); (ii) three-dimensional model generated with the remote photogrammetric technique Structure from Motion (SfM) to allow acquisition of data to complete values collected in the geomechanical station, and to create the numerical model of the critical sections of the cave; and (iii) numerical simulations using a 2D model based on the generalized Hoek and Brown failure criterion and a 3D wedge analysis. The results of the analysis show that the cave is stable, although it presents some places with small problems (falls of slabs and blocks) that deserve monitoring. Furthermore, the evaluation by the geomechanical classification Q and the corresponding abacus of cave stability indicates that it is located in the “transition” zone where attention is required. In addition, SfM photogrammetric technique makes possible to generate a geometric 3D model that allowed the acquisition of data that were difficult to take in situ. The geotechnical parameters obtained from the different methods complement each other, resulting in a more realistic engineering representation of the subsurface environment. As a conclusion, a graph showing the two empirical methodologies (Barton’s Q Index and CGI), and some recommendation for a future analysis are given.
1945 Hospital at Home - developing a novel simulation induction programme through quality improvement
Authors: Watson G , Paveley A , Chin K , Lindsay-Perez A , Schiff R 
Published: January 2024

Abstract

Introduction
The UK is expanding provision of acute medical care in people’s own homes through Hospital at Home (H@H) and virtual wards. Our H@H service is training junior doctors to meet the growing clinical need in this environment. We describe the use of simulation training to improve the H@H induction process.

Methods
From their experiences in H@H, junior doctors identified specific training needs to build relevant competencies. From this feedback, PDSA cycle one involved junior doctors designing a dedicated simulation training (H@H-SIM). Stations addressed clinical, practical and advanced communication skills required in H@H using high- and low-fidelity simulation. PDSA cycle two used post-course evaluation to refine H@H-SIM through introduction of FP10 prescribing stations, point-of-care testing (POCT) and greater emphasis on practical skills. Revisions were evaluated via participant questionnaire before and after the H@H-SIM.

Results
Cycle two of H@H-SIM involved twenty doctors. The clinical scenarios, prescribing and practical skills stations, including POCT and IV administration, were perceived as the most useful parts of training. Overall self-rated confidence in knowledge and skills to work in H@H improved from a mean of 6.9 to 7.7/10. Before H@H-SIM, 60% were ‘not confident’ with recognising end of life (EOL), IV administration or decision-making around remaining at home; 10% with advance care planning (ACP). After H@H-SIM, 10% felt ‘not confident’ with recognising EOL or ACP and 5% with IV administration. Concerns persisted with using equipment, prescribing and availability of senior support. An additional station on recording ECGs was suggested.

Conclusions
Working in a H@H context and seeing patients in their homes can be daunting for junior doctors. H@H-SIM embedded into induction is one way to prepare doctors for this role, improve their confidence and has potential for wider replication.