bluuebunny/crossref_metadata_2025 huggingface dataset:
Правове регулювання медіації у публічному управлінні
Authors: Мельничук Ольга , Саліхов Олексій
Published: October 2024

In this article the legal regulation of mediation in public administration is highlighted. It is indicated that the development of legislation on mediation shows the progress of the state in the direction of introducing alternative measures to facilitate access to justice, establishing partnership interaction between public authorities and private individuals.
First of all, the Convention on the Protection of Human Rights and Fundamental Freedoms of November 4, 1950 had a significant impact on the development of mediation as a tool that ensures the effectiveness of resolving legal disputes. In order to implement its provisions regarding the right to a fair trial and the right to an effective remedy, the Committee of Ministers of the Council of Europe adopted a number of recommendations.
Recommendation Res (2001) 9 to member states on alternatives to judicial review of disputes between administrative bodies and private parties dated September 5, 2001 is of great importance to implement the mediation institution in the field of public administration. The adoption of this document contributed to the establishment of the administrative mediation institute. For a better implementation and understanding of this Recommendation, the European Commission for the Efficiency of Justice adopted the Guidelines, which focused on the role of participating states, their administrative bodies, judges, and lawyers in taking measures to implement mediation.
The ratification of international legal acts and the adoption of the framework Law ofUkraine «On Mediation» by the Verkhovna Rada of Ukraine, which were supplemented to a number of codes and other laws regarding the application of mediation, created legal grounds for itslegalization in public administration
Evolving Balance of Power in the Middle East: Iran-Israel Standoff Shaping Iranian Foreign Policy
Authors: Tanvir Rida , Abbas Syed Qandil
Published: October 2024

The Israel-Iranian conflict can be considered a major contributor to changes in the power balance in the Middle East. This competition has profound implications for regional stability and has impacted almost every realm of Iran's foreign policy. It influences its decision-making regarding its domestic policies, strategy on military actions, neighboring countries, and its nuclear plan. If both countries head towards different goals, which they currently are, there is a high possibility of an escalation that will have severe impacts on both regional and international security. The principal item of Iran's "deterrence strategy" is developing and placing missiles capable of reaching Israel. Iran also threatens Israel directly and makes a buffer zone through proxy peoples' wars in Gaza, Lebanon, and Syria. This conflict has led Iran closer to many non-state actors and governments in the region than ever before.
Analysis of the Accuracy of Writing Simple Stories Assisted by Picture Series Media in Elementary School
Authors: Fatmi Rohmah Nur Hidayati  , Markhamah  , Fitri Puji Rahmawati
Published: October 2024

This study aims to describe the effectiveness of Indonesian language learning in writing simple stories with serial picture media. This simple story writing skill has indicators that include: the suitability of simple stories and writing simple stories. The type of research conducted is descriptive qualitative with data in the form of simple stories as the basic material for study and analysis. The data in this study are simple story writing of students in class II SDIT Muhammadiyah Al-Kautsar. The data sources in this study were 20 students, the techniques used in the research were simple story writing test techniques. Data collection in the study through the task of writing a simple story with serial image media. The results of research at SDIT Muhammadiyah Al-Kautsar related to simple story writing skills, namely, students in writing simple stories using serial image media can follow well so that students are able to compile simple stories by understanding the indicators in writing skills coherently. In addition, students are very enthusiastic in using serial image media as a solution in compiling and writing simple stories. However, in the writing accuracy indicator, students have not been precise in writing simple stories.
Structure and Hydraulic Analysis of a 5-Ton Hydraulic Press by Simulation
Authors: Tuong Nguyen Nhat , Truong Tran Van , Khanh Pham Quoc , Nga Pham Thi Hong , Phong Duong The , Tan Nguyen Thanh
Published: October 2024

This study outlines a comprehensive approach to designing, simulating, and manufacturing a 5-ton hydraulic press. It begins with the calculation and design of the hydraulic system and machine frame based on the machine’s specifications. The hydraulic circuit is then simulated using Matlab Simulink software with the Simscape Hydraulic tool to validate the hydraulic drive system calculations. Furthermore, different machine frame structure options are analyzed using the finite element method (FEM) with Altair Simlab software, and the most optimal option is selected based on structural criteria and material usage. Finally, the chosen design for the hydraulic press is manufactured and tested. The hydraulic press was reliable during testing, validating the design and simulation phases. The 5-ton press is achieved by the hydraulic system operating effectively at the calculated pressure of 65 bar, with a pump flow rate of 6.5 l/min and a cylinder stroke of 200 mm. The machine frame exhibits outstanding structural integrity with a maximum stress of 83.635 MPa, a maximum displacement of 0.265 mm, and a safety factor of 2.98.
A Generative Approach to Mass Optimization of Wheel Assembly
Authors: Raju Amritha , Siddharth S. , Jain Jake , Arjun A.P. , Srinivasan L. , Sivarajan S.
Published: October 2024

Generative design in CAD software, driven by cloud computing and AI, optimises 3D models for various industries. It focuses on improving manufacturability and reducing mass within design and cost constraints. This research targets minimising the mass of the wheel assembly, including A-Arms, Upright, Wheel Hub, Brake caliper, and Rims. Mass minimization is essential as a lighter wheel assembly contributes in improving fuel efficiency, braking performance and promotes sustainability as it reduces carbon emissions. The components designed in Solid Works are optimised using Fusion 360, considering input parameters, materials, design constraints, and manufacturing requirements. Finite Element Analysis (FEA) in ANSYS under Static Structural conditions evaluates the feasibility of the design. On comparing the initial and final models respectively based on parameters like Factor of Safety, and Von Mises stress with the prime objective being mass optimization, a 27.94% mass reduction of the assembly is achieved as a result of generative design while maintaining the structural integrity and improving the performance characteristics of the vehicle witnessed a remarkable change.
Research and Design of Hydraulic System for CNC Radial Drilling Special Machine Tool
Authors: Zhang Yanhong
Published: October 2024

The petroleum perforation gun is a very important tool in the petroleum extraction industry. The processing of shallow blind holes in the manufacturing of petroleum perforation guns is a key and difficult point in the processing technology. Traditional processing requires experienced and experienced turning masters to process, which is time-consuming and laborious. CNC radial drilling specialized machine tools can achieve automated high-precision processing, high efficiency, good quality finished workpieces, and consistent shallow blind hole depths. CNC radial drilling specialized machine tools are increasingly widely used in oil well exploitation. This paper aims to design a hydraulic system suitable for CNC radial drilling special machine tools. Firstly, this article introduces the application background and main performance parameters of CNC radial drilling special machine tools. Then, a hydraulic system design scheme was proposed, including system framework, hydraulic component selection, pipeline design, etc. Next, performance verification and evaluation will be conducted on the designed hydraulic system, including verification of performance indicators, stability and reliability of the system.
Optimization Design of Harmonic Drive Flexspline Fixture Based on Orthogonal Experiments
Authors: Hu Qiushi , Li HaoQiang , Liu Fujiang , Wang Guowei
Published: October 2024

As a thin-walled, highly deformable precision component, the flexspline is subjected to complex stresses during operation. The fixture is crucial for the manufacturing of the flexspline, requiring a rational structure to ensure manufacturing precision. In this study, a finite element model of a flexspline fixture was established to analyze the contact pressure and strain between the flexspline, expansion sleeve, and core shaft. By utilizing orthogonal experiments and simulations, the maximum contact pressure between the flexspline and the expansion sleeve Pfmax, the maximum contact pressure between the expansion sleeve and the core shaft Pemax, and the maximum strain εfmax of the flexspline were obtained under varying pulling force F, taper angle α, and the number of clamps S. Range analysis was conducted to investigate the impact of F, α, and S on Pfmax, Pemax, and εfmax. These findings provide valuable references for designing and optimizing harmonic drive flexspline fixtures.
Mountain Micro Pile Drilling Rig and Micro Pile Foundation Construction Technology
Authors: Wu Fenqian , Chen Weiyu , Li Yangsen , Liu Ruijun , Yan Yan
Published: October 2024

As the construction of transmission lines increasingly extends to deep mountains and ridges, the research on mountainous micro-pile drilling rigs and transmission line micro-pile foundation construction technology has become increasingly important. This article discusses the characteristics of mountain micro-pile drilling rigs in the construction of micro-pile foundations for transmission lines and its application in mountain construction. The article introduces the structure and working principle of the mountain micro-pile drilling rig, and analyzes its adaptability in different environments. In addition, the article also elaborates on the construction technology of micro-pile foundation for transmission lines, focusing on the construction process of micro-pile foundation based on the down-the-hole mountain micro-pile drilling rig. This research provides valuable ideas and methods for the construction of mountain transmission lines, and has certain theoretical and practical value for improving construction efficiency, ensuring project quality, and saving costs.
Design and Application of Loading System for Mine Reducer
Authors: Chen Xiaoqiang
Published: October 2024

The quality of gear reducer overhaul plays a decisive role in the stability of coal mine equipment overhaul. This paper introduces the design of a loading test system for gear reducer in coal mine. Through the establishment of the test bench, the loading test, temperature rise test and efficiency test of gear reducer overhaul can be realized, so as to improve the quality of gear reducer and avoid the abnormal operation of equipment due to gear reducer installation failure. This reducer loading test-bed can be widely used in the overhaul industry of continuous excavation equipment. The reducer is an indispensable part of the mechanical transmission device, it is widely used in many fields in our country, with the rapid improvement of China’s industrial development and the popularization of mechanization, the use of the reducer is also more and more broad, but in some large industrial and mining enterprises, the working environment of the reducer is relatively harsh, so the design of the reducer loading test bed has no advantages Measurable significance, in the last process of the reducer production of its a series of performance testing, such as temperature rise test, noise test, durability test, overload test, no-load test, this loading test bench designed a small power reducer test bench for a loading scheme, the scheme variable load method is simple and reliable.
Design and Application of New Propulsion Mechanism for Construction Machinery
Authors: Yan Yan , Huang Xiaoyu , Zhang Jinbo , Liu Ruijun , Chen Weiyu
Published: October 2024

With the rapid development of China’s railway and highway system, construction machinery is playing a more and more important role in this field. Then, the mechanical engineering equipment performance is particularly important. Starting from the application of anchor excavator in practice, this paper designs a new type of propulsion mechanism, which will greatly play the important role and improve the production efficiency when applied to practice. Due to the high recovery, high load and high vibration of the propulsion system of anchor excavator, fatigue failure is easy to occur, which leads to the damage of the whole machine. According to its working conditions and technical requirements, a hydraulically driven chain gear drill device is designed, which constitutes the whole propulsion mechanism. Practice shows that this new type of propulsion mechanism can greatly reduce the hidden trouble caused by centrifugal rock drill and increase the safety and stability of operation. In the future, this equipment can be widely used in the work of anchor digging machine.
Design of Increasing Cutting Range for Cantilever Tunneling Machines Used in Coal Mines
Authors: Hu Yong
Published: October 2024

Due to the actual production needs of underground coal mines, during the tunnel excavation operation, due to the increase in the width and height of the tunnel section requirements, the traditional tunnel boring machine in use may not be able to meet the design requirements of the actual tunnel section, and must be expanded and upgraded in the height direction and width direction of the original tunnel. The traditional solution is to replace the original tunneling equipment, but this method greatly increases the material cost. In order to reduce costs and increase efficiency, it is a reliable and simple method to upgrade and transform the original tunneling machine. The original tunnel boring machine can be improved in two aspects according to the actual use requirements of the customer: increasing the height of the fuselage and the length of the cutting arm to adapt to changes in the coal seam and increase the cutting range and other usage requirements. At the same time, during the design process, not only the increase in length and height must be considered, but also the interference of the size and angle of the fuselage needs to be verified to ensure that the functional modification of the equipment is reasonable. This method not only provides a strong basis for increasing the cutting capacity and range of the tunnel boring machine, but also greatly broadens the equipment’s functions. It is a cost-effective and efficient improvement plan, and it also provides tunneling equipment for other tunnels and even non-coal tunnels reference basis.
Examining the Effect of the Fe3O4-Doped Nanofluid MQL Method on the Machining Performance of Al-Mg-Si Alloy
Authors: Yücel Muhammed , Aydin Alper , Sağdiç Ömer Faruk , Yapan Yusuf Furkan , Uysal Alper
Published: October 2024

Nowadays, various problems, such as high thermal expansion coefficient and built-up edge, occur in the aluminum (Al) alloys machining. Considering the widespread use of aluminum alloys due to their advantages such as low density and corrosion resistance, the need for sustainability and efficiency in the Al alloys machining increases. In the presented study, for the first time, Fe3O4 nanoparticle-doped vegetable-based cutting fluid was used in the turning of commercial Al-Mg-Si (Al6082) alloy using the MQL method, and its effect on chip removal performance was examined in terms of resultant cutting force (Fc), cutting temperature (Tc), consumed energy (ET), and surface roughness (Ra). The results showed that the MQL method using Fe3O4-doped nanofluid reduced the average values of the Fc, Tc, ET, and Ra by 2.3%, 4.7%, 17.8%, and 13.6%, respectively, compared to dry cutting conditions. While a low feed value should be used in terms of Fc, Tc, and Ra, a high feed value should be used in terms of ET.
Effect of Extrusion and Annealing Treatment on Peripheral Coarse Grain Structure and Mechanical Property of an Al-Cu-Li-Mg Alloy Extrusion Profile
Authors: Wang Li , Wen Kai , Lin Ben , Wang Tao , Li Xiwu , Ran Hongwei , Que Jirong , Zhang Yongan
Published: October 2024

In the current study, the effects of extrusion and annealing treatment on the peripheral coarse grain (PCG) structure were investigated. The results showed that the edge of profiles recrystallized during the extrusion process, the grain size was in the range of 2-5 m and the degree of recrystallization had obvious heterogeneity along the extrusion direction, showing two kinds of recrystallization microstructure. The thickness of recrystallized microstructure at the head of the profile was 2 mm and there were obvious boundaries. The thickness of recrystallized microstructure at the tail reached 13 mm and there was no obvious boundary. The recrystallized grains grew abnormally to form PCG structure during the solution process. The PCG structure was significantly reduced when the extrusion ratio decreased from 20 to 14. The higher the extrusion temperature reached, the more serious the PCG structure was. The suitable annealing regime is 350°C/5h.
Effects of Solution Temperature on Microstructure and Properties of Zn-2Cu-0.8Mg Alloy
Authors: Gu Shenyi , Zhang Yan , Wang Hongxing , Zhang Xinxiang , Zhou Tao , Zhen Zhihao , Li Yaoyang , Zhang Xize
Published: October 2024

Zn-2Cu-0.8Mg zinc alloy was prepared by metal mold casting. The effects of solution temperature on the microstructure, corrosion behavior and mechanical properties of zinc alloy were studied. The results show that the microstructure of zinc alloy is mainly composed of η-Zn, Mg2Zn11 and a small amount of CuZn5 compounds. As the solution temperature increases, η-Zn content increases, the grain size increases, from dendrite to equiaxed crystal to coarsening; The tensile strength and elongation of the solid solution alloy are higher than those of the as cast alloy, and decrease with the increase of solution temperature. The alloy after 320°C solution treatment has the maximum values of mechanical properties, which are 396 MPa and 1.18% respectively, 1.3 and 1.8 times of those of as cast alloy; Fracture analysis shows that the fracture mode of zinc alloy is mainly cleavage fracture. The electrochemical test shows that the corrosion resistance of zinc alloy increases with the increase of solution temperature, and the self-corrosion current density of the alloy after 380°C solution treatment is the lowest, 14.965μA.cm-2. The corrosion rate is the lowest, 0.022mm/y.
The Creep Constitutive Theory Considering the Effects of Strain Hardening and Damage
Authors: Meng Li , Chen Wufan , Wei Cunjin , He Xu
Published: October 2024

A reasonable creep constitutive model must obey the fundamental rules of thermodynamics while ensuring accuracy in description. This paper derives a creep constitutive model considering damage based on the thermodynamic laws. The study done by external forces acting on materials is transformed into the materials’ free energy and dissipated energy. The free energy is decomposed into two parts: creep free energy related to creep damage and thermal-elastic deformation free energy, which the decay of free energy means the decrease in material creep resistance. According to the conjugacy of internal variables and the orthogonality of dissipation directions, the evolution equation of thermodynamic forces is obtained through the dissipation potential function. The theoretical model considers the combined effect of creep hardening and creep damage, describing the evolution of strain rate in the three creep stages and predicting creep life. Creep data of P92 alloy at 650°C are selected to verify the accuracy and rationality of the model.
Study on Application and Failure Rule of Composite Transmission Shaft
Authors: Cao Jingyi , Yin Wenchang , Fang Zhigang , Xia Chenxi , Wang Zhanbin
Published: October 2024

The drive shaft is one of the key components of the transmission system such as helicopter and automobile. With the progress of science and technology, the use of composite transmission shaft instead of metal transmission shaft is an inevitable trend in the development of lightweight helicopters. In order to better understand and study the characteristics of the composite transmission shaft, give full play to its advantages of lightweight corrosion resistance, this paper focuses on the structural characteristics of the helicopter composite transmission shaft, the application, the problems in the maintenance process and the future development direction and trend. The difference of typical failure modes of the composite drive shaft caused by different structural states and different materials is given, and the corresponding failure mechanism is revealed. It provides a powerful support for the application and technical improvement of the composite drive shaft.
Analysis of the Effect Pattern of Mixing Ratio and Age on the Conductivity of Concrete
Authors: Chi Hongyou , Zhang Shenghang , Tang Lei , Li Jun , Li Po , Pan Wenming
Published: October 2024

Concrete is the most widely used building material, and its electrical index test has received more attention in recent years. The samples of different mix proportions (water-cement ratios, sand rate, accelerator) were made and tested by impedance analysis. The results show that the impedance analysis method can eliminate the polarization effect and test the electrical properties more stably; With the increase of age, the relationship between electrical conductivity and water cement ratio gradually changed from positive correlation to negative correlation; The conductivity of the sample with accelerator was slightly higher than that without accelerator; The electrical conductivity of concrete is basically negatively correlated with the sand content. There is no order of magnitude difference in the electrical index of concrete in the concrete mix ratio, and the difference gradually decreases with the increase of concrete age. The experimental results can provide reference for electromagnetic detection work.
Study on Failure Behavior of Composite Single Nail Link Structure
Authors: Yin Wenchang , Li Liang , Cao Jingyi , Fang Zhigang , Xia Chenxi , Wang Zhanbin
Published: October 2024

When the composite laminate single nail connector is subjected to 60,000 cycles under an alternating cyclic tensile load of 7∼9KN, the specimen is damaged. The cause of the failure sample was determined through macroscopic and microscopic morphology observation, internal damage CT examination, decomposition examination, chemical composition examination, and size measurement. The results indicate that the rivet in the middle of the sample is noticeably misaligned, the two semi-composite plates are axially displaced, and the composite material is slightly bulging and deformed at the nail holes. The riveting body failed due to deformation caused by composite extrusion, resulting in a typical composite extrusion failure along with fastener fracture composite failure. There is a small gap between the composite and the riveted body at the local level, leading to impact reaming and dislocation deformation during testing. This is the primary reason for premature failure of the test component.
Modelling Creep Lifetime of Grade 91 Steel Based on Grain Boundary Cavitation
Authors: Wu Yuandi , Lu Joan , Xu Qiang
Published: October 2024

The creep rupture model developed based on creep cavitation is a physically based method for predicting creep life. By combining creep damage mechanisms with experimental data to establish a creep rupture criterion, this approach provides greater confidence in applications across a wide range of stress level (especially low stress long-term creep) and for extrapolation. This study reported the creep lifetime prediction of a creep rupture model based on creep cavitation for Grade 91 steel over a wide range of stress level. A temperature-dependent function was introduced to creep rupture model to assess the accuracy and reliability across muti-temperatures. The results show that the creep rupture model developed based on creep cavitation achieves high accuracy over a wide range of stress level (1MPa to 450MPa) and temperature. The trend of lifetime prediction curves has a good agreement with experimental data, shows great extrapolation potential. More reliable for long-term low-stress creep life prediction.
Corrosion Inhibition Performances of HPAA on A3 Carbon Steel in Different pH Values Sulphuric Acid Medium
Authors: Gao Yuhua , Li Haihua , Liu Jiaxin , Liu Zhenfa
Published: October 2024

The corrosion inhibition performances of HPAA on A3 carbon steel in different pH values sulphuric acid medium were investigated by weight loss method. The corrosion inhibition performances of HPAA have a significant decrease with pH value from 3.0 to 7.0, while it has changed little without corrosion inhibitors. The corrosion inhibition rate was only 8.5% at pH was 3.0 while the corrosion inhibition rate was 86.5% at pH was 7.0. The corrosion inhibition efficiency gradually improves with the dosage of HPAA increases at the same pH value. The surfaces microstructures of carbon steel coupons were studied by using SEM and EDX microanalysis. SEM and EDX analyse datas showed the addition of HPAA could form a protective film on the surface of carbon steel coupon to slow down its corrosion and HPAA used for sulfuric acid medium have good protective effect on A3 carbon steel.
Preliminary Study on Water Stability of Solidified Silt with Steel Slag Matrix Composites
Authors: Yue Hongzhi , Wu Wenjuan , Wang Yang , Zhao Lin , Sun Zhaoyun , Su Chunhua , Wei Jincheng , Hu Guiling
Published: October 2024

Aiming at the engineering problem of poor water stability of silt in the Yellow River area, a curing agent (SBCG) was prepared with steel slag, granulated blast furnace slag, and desulfurized gypsum as the main materials to improve and solidify the alluvial silt of the Yellow River. Taking the unconfined compressive strength and CBR as the main indicators, the water stability performance of SBCG-solidified silt was studied through water immersion tests. Meanwhile, the pore characteristics of the solidified silt were observed by Nuclear magnetic resonance (NMR). The results show that the addition of SBCG can obviously improve the engineering properties of silt soil. The standard curing strength is significantly improved with the increase of SBCG content, the guarantee rate of water immersion strength at 7d age is all greater than 80%, and the CBR after immersion still meets the requirements of subgrade strength. According to the change law of the strength of the solidified silt under different test conditions, the preferred dosage of SBCG is determined to be 6%∼10%. The pore structure characteristics are an important factor affecting the water stability of solidified silt. The large pore volume and the porosity of solidified silt decreased significantly with ages.
Thermoplastic Polyurethane (TPU) and Nitrile Butadiene Rubbers (NBR) as Promising Materials for Elastomeric Microfluidics and Cryomicrofluidics
Authors: Anshin Sergey M. , Biryukov Vladimir P. , Gradov Oleg V. , Prince Anton N.
Published: October 2024

TPU (thermoplastic polyurethane) and NBR (nitrile butadiene rubber) are both known for their elasticity and mechanical resilience, making them attractive candidates for applications requiring flexibility. By focusing on the mechanical adequacy of elastomeric materials like TPU and NBR, researchers can optimize the design and performance of flexible chips for microfluidic systems The focus on the mechanical properties of elastomeric materials like TPU and NBR for microfluidic applications is crucial due to their role in enabling reversible deformation. Understanding how these materials respond to different mechanical stimuli and environmental conditions is essential for developing reliable and efficient microscale devices with enhanced functionality. Studying the elastic behavior of materials like TPU and NBR is essential for ensuring their suitability for tasks involving fluid manipulation, mixing, and control within microscale devices. In elastic microfluidic systems, the integration of flexible chips is critical for enabling dynamic fluid manipulation and control. Flexible chips with tailored mechanical properties can deform and stretch in response to fluid flow, allowing for precise tuning of flow rates, mixing efficiencies, and sample handling. This research direction holds promise for advancing the field of microfluidics and expanding the capabilities of elastic microfluidic platforms in various scientific and non-military technological applications.
Research on Steel Sheet Pile Cofferdam Based on Stress Seepage Coupling Analysis
Authors: Du Guilin , Zhao Xiaoyang , Xu Dabin , Yang Pengcheng
Published: October 2024

Steel sheet pile cofferdam is widely used in sandy soil, viscous soil and deep foundation pit because of its advantages of low cost, strong overall stiffness, short construction period, easy penetration into hard soil and good waterproof performance. Due to complex working conditions and many uncontrollable factors in the construction process, it is necessary to simulate and analyze the construction conditions in advance. The steel cofferdam in the soft soil area is a weathering layer, which is difficult to construct. In order to ensure the structural safety of steel sheet pile cofferdam and control its water use area, the influence of multiple design parameters on the deformation of cofferdam was studied by single factor sensitivity analysis method, and three-dimensional finite element model was calculated by Midas software. The finite element numerical simulation method is used to simulate and calculate each construction condition, analyze the deformation and stress changes of cofferdam and surrounding soil, and the deformation and internal force conditions of steel sheet pile cofferdam and internal support structure in the construction process. Through comprehensive analysis of theory and on-site construction conditions, the construction factors affecting steel sheet pile cofferdam, internal support structure and surrounding soil are obtained. The change of soil gravity stress caused by precipitation during construction leads to excessive deformation and stress concentration. And the establishment of internal support has played a good deformation control phenomenon.
Failure Analysis of Cracking at the Edge of T-Weld Between Boiler Cylinder and Tube Plate
Authors: Gao Zhen , Zhang Fangfang , Chen Xiaolong , Yu Chengcheng , Yu Ting
Published: October 2024

A company had a WNS10 boiler operating for 16 months when it experienced a catastrophic failure. The failure occurred at the edge of the T-weld between the shell cylinder and the rear tube plate at the rear of the furnace, and the weld cracked on the cylinder side. At the same time, the outer guard plate cracked due to the impact of airflow. We used macroscopic observation, physical analysis, metallographic analysis, and scanning electron microscope analysis to study the cause of the cracks. It was found that the fracture was mainly characterized by brittle fracture. The physical phase analysis found that the Ca and Si contents in the boiler water were high, and there was scaling at the failure site and severe corrosion under the scale. Finally, it was concluded that the boiler has apparent oxygen corrosion, subscale corrosion, and stress corrosion. Oxygen corrosion and corrosion under the role of scale corrosion in the boiler tube localized pits, pits tip part of the corrosion products due to the corrosion of the wedge caused by the addition of tensile stress and the emergence of micro-cracks. After the formation of micro-cracks in the boiler operating pressure, welding, and manufacturing process of residual stress and corrosive media under the joint action, cracks gradually expand, eventually leading to cracking.
Structural and Flow Field Simulations of Underwater Inspection Equipment for Nuclear Power Pipelines
Authors: Luo Jie , Lin Shichang , Xiao Xiaonan , Liu Shun , Chen Zhixian , Zhang Qingyu
Published: October 2024

During the construction and operation of nuclear power plants, equipment components are affected by various environmental and operational factors, which include high pressure, elevated temperature, radiation, hydrogen absorption, corrosion, vibration, and wear. Such conditions can significantly affect the material properties of these components, leading to issues like aging, embrittlement, fatigue, and the formation and propagation of defects. This study focuses on the previously designed underwater inspection equipment for nuclear power pipelines, which can conduct in-service underwater inspections of these pipelines. In order to ensure the reliability and effectiveness of this equipment, based on Computer-Aided Engineering (CAE) simulation analysis, this paper uses ANSYS Workbench software to simulate the structure and flow field of the equipment in detail. The results of the simulation analyses indicate that the structure of the underwater inspection equipment for nuclear power pipelines in this study is stable under the specified operating conditions. Additionally, the strength, rigidity, and maximum water flow capacity of the equipment are found to meet the design requirements. This simulation confirms that the underwater inspection equipment is well-suited for its design purpose, providing strong theoretical support for its further experimental verification.
Vehicle Preventive Fault Detector and Data Acquisition Scheme
Authors: Wang Yumeng , Wang Xin , Zhang Xu
Published: October 2024

Vehicle reliability is one of the important indicators for evaluating vehicle performance. Drivers or technicians often cannot detect or accurately determine the failure location and form in the early stage of vehicle component failure, which is very detrimental to the safety of vehicle users and the brand effect of production enterprises. Therefore, a set of automotive preventive fault detectors has been developed, which can be used on the complete vehicle and automotive component test benches. The detectors can monitor the status of various automotive components through sensors, evaluate and judge the vehicle status through software, and issue an alarm to the driver and test personnel when early failures may occur. Therefore, it can ensure the safety of vehicle users or test personnel, and is also beneficial for analyzing the initial status and cause of failure components. The equipment and testing method have been applied in the vehicle and component testing platform and the results indicate that the device can accurately determine the failure location and form in the early stage of component failure.
Modelling Long Term Creep Deformation and Creep Damage and the Extrapolation Methods
Authors: Lu Joan , Xu Qiang
Published: October 2024

Modelling long term creep deformation and creep damage is vital important for power generation industry as the Generation IV Nuclear Reactors are now expected to work for 60 years. This is due that the knowledge about long term creep deformation and creep damage required for safe and economical operation is unlikely to be directly obtained through experiments, due to the constraint of time and cost. However, the application of the traditionally obtained empirical based time-temperature parameter approach is not very successful, due to the stress breakdown phenomena. It is the authors view that the new approach must be mechanism-based and can be calibrated using short term experimental data to ensure its extrapolation credential. Following this thought, the authors have (1) proposed the modified shine law for minimum creep strain rate for wide range of stress, (2) developed creep cavitation damage model based on cavitation and the creep lifetime model. Here, we summarize such work first, then explore their extrapolation capabilities. It concludes with the author’s view on the future research topics. This paper orientates and steers research activities.
Modelling the Flexural and Shear Behavior of Clay Based-Concrete Bilayer Beams Externally Retrofitted with Jacketed FRP Composites
Authors: Taleb Souad Ait , Salem Abdelmadjid Si , Ahmed Chafika Ali , Taouche-Kheloui Fatma , Tahar Kamal Ait
Published: October 2024

In order to reduce the Portland cement usage in concrete manufacturing several eco-friendly mix design has been proposed in literature, through the recourse to bio-natural products. Such technologies aim to reduce the global warming and the CO2 emission during cement manufacture. In this respect, bilayer-composite beams prepared with ordinary and clay-based concrete externally reinforced with flexural and shear GFRP-Jacket were designed and simulated in the present work. Indeed, nonlinear finite element simulations were established to evaluate the four-point bending and shear features of the suggested all composited beams. Accordingly, the novelty of this study is to propose and to validate nonlinear models (NLFEM) able to model the material behavior of concrete and clay based-concrete through an elastic-plastic damage model and anisotropic model for the constitutive behavior modelling of composite laminates. The accentuated numerical results in terms of local and global behavior are correlated with a high agreement to experimental ones.
Dynamic Modeling and Analysis of Parallel Stable Platforms Under Irregular Waves
Authors: Song Mingwang , Wang Shenghai , Zhang Jinhui , Sun Kezhen , Zhao Shilong
Published: October 2024

The parallel stabilization platform is mostly used for wave compensation of offshore stabilized bridges, and its anti-rolling effect determines the safety and efficiency of personnel transfer, and is an important offshore anti-roll equipment. The research related to traditional parallel platforms mainly focuses on the research under the waves with simple rules. In this paper, a parallel stabilized platform structure with intermediate columns is proposed, and considering the ship motion caused by irregular wave excitation, considering the ship motion caused by irregular wave excitation, the kinematic model and dynamic model of the parallel stable platform are established, and the irregular waves are modeled by Ansys-AQWA according to the JONSWAP spectrum, which is widely used to simulate ocean waves in Chinese waters., and the Matlab-Adams joint simulation is carried out under the irregular wave excitation, and the simulation results prove the accuracy of the built dynamic model.
Nonlinear Vibration Isolator with Softening Spring and Nonlinear Damping
Authors: Puzyrov Volodymyr , Losyeva Nataliya , Savchenko Nina
Published: October 2024

In recent decades, nonlinear isolators have become widely used to solve problems of passive isolation of unwanted vibrations. A special place is occupied by nonlinear stiffness isolation supports, which provide high static stiffness along with low dynamic stiffness or even quasi-zero stiffness (QZS) in the displacement range. These vibration isolators provide a higher isolation bandwidth with low transfer capacity than conventional linear devices. In this paper, nonlinear single-degree of freedom (DOF) vibration isolator with quadratic and cubic nonlinear stiffness components and a quadratic damping component is analyzed. The system responses and magnitude of force transmissibility in the vicinity of resonant frequency are analyzed. The dynamic response is obtained using the harmonic balance method. A significant contribution from the quadratic component of the damping force is emphasized. Also asymptotical formulas for responses magnitude, resonant frequency and force transmissibility there are presented, which allow optimizing the choice of the parameters of the isolator more easily.
Development of 5 Axis Robotic Manipulator for Material Handling and Sorting
Authors: Naranje Rajratna A. , Kale Kalyan J. , Chavan Pranavkumar P. , Kumar Vishant , Kumar Naveen
Published: October 2024

The creation and application of a 5-axis robotic arm intended for material handling and sorting tasks is shown in this work. Our 5 Degree of Freedom (DOF) robotic manipulator prototype was developed in response to the growing use of robotics in many industries to solve difficult problems. Now industries are using Robots in place of CNC machines. The manipulator’s mobility is controlled using programming that makes use of open-source technology, particularly Arduino. Furthermore, to guarantee sufficient lifting capability, we integrated servo motors with different torque specifications at each joint and used Fused Deposition Modeling (FDM) 3D printing technology to fabricate the hardware components. Because of the use of the open source technology, low cost microcontroller (Arduion), and servo motor, the developed 5 DOF robotic manipulator is cost effective and reliable. For the study and research of transformation matrices, kinematics, and other related robotics issues, this articulated robotic arm is a useful tool.
Aquila Optimizer Approach for Inverse Kinematics of Welding Robot Manipulator
Authors: Ganesan Kanagaraj , Rahim Sheik Masthan Shahul Abdul
Published: October 2024

Absolute accuracy is one of the essential performing properties of an industrial manipulator and is critical for emerging robotics applications such as laser cutting, welding, painting, inspection, as well as many machining operations. For efficient trajectory tracking of industrial robots, a cumbersome computation of inverse kinematics is needed to control the manipulator position and orientation to the prescribed trajectory, but the primary issue with the inverse kinematics technique is its computational complexity. With a greater number of links, the complexity of a redundant manipulator increases even further. This study proposes to solve the inverse kinematic problem with Aquila Optimizer (AO) algorithm. Extensive simulation experiments are carried using Yaskawa’s MH5 robot in the MATLAB environment to verify the efficiency of the algorithm for closely following the pre-defined trajectories. Simulation results showed that the AO algorithm-based approach shown better performance in terms of minimum position error while maintaining reasonable computational effort.
Implementation of Deep-Learning-Based Object-Tracking Function on a Mobile Robot
Authors: Nguyen Duc-Nam , Tran Hoang-Ha , Nguyen Duc-Binh
Published: October 2024

Object tracking is an important function of stream video processing systems especially in robotics and mobile vehicle applications. However, real-time object tracking on an embedded computer or an edge device is critically limited because of computing resources. This paper presents the design and implementation process of a deep-learning-based object-tracking functionality on a mobile robot. An NVIDIA Jetson development board with low computation resources was used to train and deploy a deep learning model called MobileNet. The data extracted from the image processing was used for calculating and updating the steering angle by the use of a computer vision routine. An embedded board was used to maneuver the mobile platform by applying the PID algorithm. The results showed that the accuracy of detection is up to 97% at 13 fps while the mAP is 88%. The prototype mobile robot can be used as service-robots like a tennis ball collector, or rubbish collector, or upgraded to large-scale autonomous vehicles, etc.
Research and Development of Defect Detection Device for Deep Hole and Large Thread Based on Rotating Linear Array CCD
Authors: Liu Yanhua , Hu Yuhang , Zhang Xiangtao , He Gaoqing , Chen Bingxuan
Published: October 2024

With the attention of the country to the ecological environment, nuclear energy has been vigorously developed, and the deep internal thread on the nuclear reactor dome cover is easy to appear scratches and collapse problems during operation. In order to solve the defect identification problem of deep hole internal thread, this paper puts forward a system to identify the defect of deep hole internal thread by using rotating linear array CCD. The system includes the image acquisition module of internal thread surface, the core control module of motion mechanism and the defect identification module. The experimental prototype of the detection system is used to complete the drive control of the rotating linear array CCD, and the defect detection system of the deep inner thread is verified by using multiple thread images, which meets the expected requirements. The acquisition method of the surface image of the deep internal thread proposed in this paper has a certain reference significance for the acquisition of two-dimensional planar expansion of the internal thread. The designed defect detection algorithm has a certain reference value for recognizing the defect images containing texture features.
Design of a Gain Scheduling Algorithm for a Three Conical Tank Interacting System
Authors: Venkataraman Aravind Pitchai , Veerapathran Veeramani , Nokerov Suleyman Malikmyradovich , Venkataraman Subramanian Pitchai , Suleiman Faiza Bait Ali
Published: October 2024

Controlling fluid levels in cone-shaped discharge tanks can be challenging, especially in the chemical industry. This paper presents a novel approach for achieving precise level control in such tanks using a proportional-integral (PI) control algorithm. Our method relies on a mathematical model of three interacting conical tanks arranged in a single-input, single-output (SISO) system. By implementing this algorithm, operators can effortlessly maintain the desired fluid level in all three tanks, as specified by the set point. This translates to direct and practical application of the derived controller parameters in real-time process control. The key to our approach lies in a gain scheduling algorithm, developed by analyzing the mass balance equation in the form of differential equations. We provide a detailed step-by-step derivation to guide researchers in their own controller design endeavors. The obtained PI controller values are tested in MATLAB and results are presented.
Stability Analysis of Shallow Buried Tunnel with Ice Water Deposits
Authors: Wu Yongan , Li Zhihong , Gao Shaoqing , Nie Yunfeng
Published: October 2024

Based on the Wanggu tunnel project of Shuangjiangkou Hydropower Station, regional geological data and survey data of the tunnel site show that groundwater in the tunnel site mainly exists in bedrock weathering, unloading, structural cracks and quaternary overburden, and there may be water gusher and mud outburst in some areas. The tunnel rock mass may develop deep and large cracks, extrusion fracture zone, etc., which has good sealing property and has no hydraulic connection with other cracks, and stores a certain amount of closed fracture water. Under the action of construction excavation, blasting and other factors, the closed fracture water suddenly gushes out, causing harm to the construction. Therefore, in tunnel construction, geological advance prediction and advance drilling should be strengthened to prevent sudden water gushing and mud outburst. Based on the strength reduction method of finite element, considering the coupled analysis of stress and seepage, the influence of snow melting on the slope stability at the tunnel entrance was analyzed by combining numerical simulation and field measurement, and the stability law of the slope of the small-clear distance tunnel in the western high-cold snow-covered area was summarized, and corresponding disposal measures were taken according to the actual situation.