Design Requirements Research Articles

Design and manufacture of equine hand prosthesis by additive manufacturing

Purpose This paper aims to design and manufacture an equine hand prosthesis using additive manufacturing, with an estimated useful life of one year. This approach offers a fast and affordable manufacturing alternative while ensuring the horse's safety, comfort and functionality. Design/methodology/approach The ground reaction force and the frequency of a horse’s walking were obtained from the literature. Mechanical tests were conducted on specimens with different manufacturing directions to determine the mechanical properties of the printed material. Finite element simulations, along with fatigue equations were used to design a geometry that respected the stress constraints. Subsequently, a prototype was manufactured in thermoplastic polyurethane using additive manufacturing technique. Findings With the aid of the proposed methodology, a new low-cost equine hand prosthesis is developed, and a prototype is manufactured. And in accordance with the design requirements, this prosthesis is intended to exhibit proper durability. Social implications This work presents an alternative way for horses facing amputation, offering a solution where euthanasia can be avoided through the use of a prosthesis to replace a part of the amputated limb. This approach could not only extend the reproductive life of matrices with high commercial value but also preserve the lives of animals with sentimental value to the owner. Originality/value To the best of the authors' knowledge, this is the first study of an equine hand prosthesis model designed for and manufactured by additive manufacturing.

Актуальные особенности договорной формы долевого строительства объектов коммерческой недвижимости

The author has substantiated the actual aspects of shared-equity construction contracts for commercial real estate. Contractual and corporate forms of implementation of shared-equity commercial construction relations are united by common goals, risks, conditions of joint investment and construction mandatory design and safety requirements. The main participants in the contractual (non-corporate) form of shared-equity commercial construction within the framework of investment projects can be individuals with the status of sole proprietors and corporate entities — investors or contractors. The implementation of shared-equity commercial construction relations is possible with the use of named (simple partnership agreement, investment agreement, shared-equity construction agreement, etc.), as well as unnamed contracts. In order to establish the commercial nature of the shared-equity construction contract, it is advisable to supplement the norms of the relevant legislation with expanded entrepreneurial powers of its parties.

Digital improvements in the design and construction process of classical Chinese garden rockeries: a study based on material digitization

Rockeries have a complex and significant role in classical Chinese garden designs. They present distinct artistic characteristics and spatial hierarchies and are crucial to garden heritage conservation. Craftsmanship in rockery construction is a significant part of China’s intangible cultural heritage. Rockeries are primarily composed of naturally occurring rocks chosen for their uniqueness and complex shapes and textures. These rocks present challenges as nonstandard elements within the traditional Chinese garden context, as it is not easy to depict them using conventional blueprints and models. This complicates the design, adjustment, display, and construction of rockeries, which lacks tangible bases for reference. Consequently, the preservation and restoration of garden rockeries is difficult, and the perpetuation and dissemination of rockery construction skills face numerous challenges. This study introduces a method that combines laser scanning and photographic measurements to digitize precisely nonstandard elements of rockery stones. This approach presents an innovative design and construction workflow for rockeries by refining design processes, showcasing real effects, and resolving assembly issues. The results demonstrate that the combination of three-dimensional laser scanning and close-range photogrammetry can accurately replicate the complex forms and textures of these nonstandard elements. The stone coding and digital management system devised based on the logic of construction effectively satisfies the design and building requirements of rockeries. Correspondingly, the proposed digital construction workflow enhances the accuracy of rockery design, presentation, and evaluation, thereby contributing to the protection and restoration of rockery heritage sites and the transmission of rockery construction techniques.

Analysis, design, and testing of mechanical switch for the backup protection of switching network unit in fusion device

Switching network unit (SNU) is one of the important systems in the power supply system of fusion devices, which excites and establishes plasma current. A mechanical switch has been designed for SNU backup protection, which can short-circuit other components in case of SNU failure to prevent further deterioration of the situation. An optimized contact system is used in this switch to improve the maintainability of the contacts. A detailed structural design was carried out for the switch, and the final prototype test results verified that it meets the relevant design requirements. This backup protection scheme can provide a certain reference for the engineering design and reliable operation of SNU.

Event-triggered impulsive control for nonlinear stochastic delayed systems and complex networks

In this paper, we probe the pth moment exponential stability (p−ES) of stochastic delayed systems subject to event-triggered delayed impulsive control (ETDIC), where the impulsive intensities are assumed to be positive random variables. Based on event-triggered mechanism (ETM) in the sense of expectation, some new sufficient conditions are developed to ensure the stability of the addressed system with Zeno-free behavior. The Lyapunov–Razumikhin method is adopted to handle the time-varying delay in continuous dynamics, and the concept of average random impulsive estimation (ARIE) is introduced to reduce the design requirements of the controller. Especially, the proposed ETDIC strategy not only generates the impulse time sequence according to the predesigned ETM, but also removes the limitations on the size of time delays. Furthermore, the ETM serves as a solution for synchronization problems in complex neural networks. Finally, two examples are given to illustrate the effectiveness of our conclusions.

Implementation of Quality 4.0 framework in the electronics sector using ANP and QFD methodologies

PurposeQuality 4.0 is essential to the Industry 4.0 framework, notably in the electronics sector. It evaluates product quality in real-time using automatic process controls, quality tools and procedures. The implementation of Quality 4.0 criteria in the electronics industry is the subject of this study’s investigation and analysis. In this study, nine Customer Requirements (CRs) and 18 Design Requirements (DRs) have been defined to adopt Quality 4.0, aiming to increase yield while reducing defects. This study has developed a Quality 4.0 framework for effective implementation, incorporating the People, Process and Technology categories.Design/methodology/approachMany CRs and DRs of Quality 4.0 exhibit interdependencies. The Analytic Network Process (ANP) considers interdependencies among the criteria at various levels. Quality Function Deployment (QFD) can capture the customer’s voice, which is particularly important in Quality 4.0. Therefore, in this research, we use an integrated ANP-QFD methodology for prioritizing DRs based on the customers' needs and preferences, ultimately leading to better product and service development.FindingsAccording to the research findings, the most critical consumer criteria for Quality 4.0 in the electronics sector are automatic systems, connectivity, compliance and leadership. The Intelligent Internet of Things (IIOTs) has emerged as the most significant design requirement that enables effective control in production. It is observed that robotics process automation and a workforce aligned with Quality 4.0 also play crucial roles.Originality/valueExisting literature does not include studies on identifying CRs and DRs for implementing Quality 4.0 in the electronics industry. To address this gap, we propose a framework to integrate real-time quality measures into the Industry 4.0 context, thereby facilitating the implementation of Quality 4.0 in the electronics industry. This study can provide valuable insights for industry practitioners to implement Quality 4.0 effectively in their organizations.

A comparative study between ultra-high-performance concrete structures and normal strength concrete structures exposed to fire

The use of ultra-high-performance concrete (UHPC) in civil infrastructure is increasing due to its numerous advantages compared to normal strength concrete (NSC). In this research, thermal analysis of NSC and UHPC beams and columns was developed to understand and compare the fire performance of these structures. A numerical analysis was performed using finite element (FE) modeling with ABAQUS software. Compared to NSC, UHPC structures in some cases have lower fire resistance due to their slender cross-sections and unfavorable thermal properties and mechanical capacity degradation due to temperature effect. The results show that UHPC structures experience significantly higher cross-sectional temperatures when exposed to fire compared to NSC. The results are particularly relevant for high-rise buildings, where fire safety requirements are more stringent and the use of UHPC is attractive, leading to an unprecedented contradiction. Alternative strategies for the application of UHPC, such as the contradictory increases in cross-section or the use of fire protection coatings, must be considered. In some cases, NSC may be more attractive as a structural material than UHPC if structural fire design requirements are taken into account.

Automatic device arrangement and wiring for fire alarm systems in metro stations: A case study

Fire alarm systems in metro stations play an important role in safeguarding lives and properties. The design process for these systems is complex and time-consuming due to the diversity of device types, wide distribution of device locations, and numerous compulsory design codes. This paper proposes an automatic design framework for fire alarm systems aimed at enhancing design efficiency. The framework includes five automated processes: information preprocessing, device arrangement, system loop generation, device wiring, and result generation. By converting the computer-aided design (CAD) results into building information models (BIM), building information and related professional device information are obtained, addressing the need for fire alarm system (FAS) design to integrate with multiple disciplines. The process can also automatically arrange FAS devices according to design specifications. Optimization algorithms, such as Ant Colony Algorithm and Prim Algorithm, are used to determine the device connection order and solve the problems of obstacle avoidance and orthogonal connections between two points. Compared to traditional design methods, the proposed automatic design framework for fire alarm systems in metro stations can not only satisfy the mandatory design requirements but also avoid the cumbersome and repetitive design process, providing new solutions for designers. Additionally, it can reduce wire length and save on construction costs. Using a real metro station as a case study, it is calculated that the automatic design can save between 8 % and 48 % of the wire length.

双行轮式自走型大白菜收获机设计与试验

Aiming at the problems of low harvesting level of Chinese cabbage, high cost of manual operation and lack of special harvesting machinery, a double-row wheeled self-propelled Chinese cabbage harvester was designed on the basis of measuring the physical parameters of 'Zaofeng 01'Chinese cabbage varieties and combining with the main local planting patterns. It can complete the root cutting, pulling, clamping and conveying, packing and collecting of double-row Chinese cabbage at one time. Through the design and selection of the key working parts of the double-row wheel self-propelled Chinese cabbage harvester prototype, the key working parameters of the profiling device, the root cutting-pulling device and the clamping conveying device were determined. The kinematics analysis of the harvester in the profiling, cutting, pulling, clamping and conveying links was carried out, and the field operation performance test of the prototype was completed. The results showed that: when the rotation speed of the cutter was 280 r/min, the rotation speed of the clamping conveyor belt was 240 r/min, and the forward speed of the machine was 1.44 km/h, the maximum qualified rate of harvesting was 95.08 %, the minimum value was 90.65 %, and the average value was 93.79 %. At this time, the working performance of the working machine is stable, the harvesting effect is good, and all performance indicators meet the relevant design requirements and standards. The research results can provide reference for the development and structural improvement of Chinese cabbage low-loss harvesting equipment.

Research on the Jet Distance Enhancement Device for Blueberry Harvesting Robots Based on the Dual-Ring Model

In China, most blueberry varieties are characterized by tightly clustered fruits, which pose challenges for achieving precise and non-destructive automated harvesting. This complexity limits the design of robots for this task. Therefore, this paper proposes adding a jetting step during harvesting to separate fruit clusters and increase the operational space for mechanical claws. First, a combined approach of flow field analysis and pressure-sensitive experiments was employed to establish design criteria for the number, diameter, and inclination angle parameters of two types of nozzles: flat tip and round tip. Furthermore, fruit was introduced, and a fluid–structure coupling method was employed to calculate the deformation of fruit stems. Simultaneously, a mechanical analysis was conducted to quantify the relationship between jet characteristics and separation gaps. Simulation and pressure-sensitive experiments show that as the number of holes increases and their diameter decreases, the nozzle’s convergence becomes stronger. The greater the inclination angle of the circular nozzle holes, the more the gas diverges. The analysis of the output characteristics of the working section indicates that the 8-hole 40° round nozzle is the optimal solution. At an air compressor working pressure of 0.5 MPa, force analysis and simulation results both show that it can increase the picking space for the mechanical claw by about 5–7 mm without damaging the blueberries in the jet area. The final field experiments show that the mean distance for Type I (mature fruit) is 5.41 mm, for Type II (red fruit) is 6.42 mm, and for Type III (green fruit) is 5.43 mm. The short and curved stems of the green fruit are less effective, but the minimum distance of 4.71 mm is greater than the claw wall thickness, meeting the design requirements.

Cosmic ray test of shashlik electromagnetic calorimeter modules for NICA-MPD

The electromagnetic calorimeter (ECal) plays a critical role in high-energy particle colliders, by measuring the energy of particles that interact primarily via the electromagnetic interaction such as electrons, positrons and photons. Fudan University has undertaken part of the mass production of ECal modules for the Multi-Purpose Detector (MPD) project of the Nuclotron-based Ion Collider fAcility (NICA). Preliminary tests on the ECal modules is an essential step in detector construction. This article introduces the cosmic ray testing of the ECal modules produced by Fudan University. We tested the cosmic ray under the conditions of horizontal and vertical placement of the module, calculated the average number of generated photons, and estimated the module’s energy resolution. Moreover we analyzed the time resolution performance of the device. The test results indicate that when cosmic rays vertically traverse the entire ECal, the number of photons produced can reach 834, with a potential energy resolution less than 5%/E. The time resolution is 189ps. Based on the comprehensive test results, the production of the ECal meets the design requirements.

Investigation of seismic response amplification effects of diverse multi-support earthquake excitations on cable-stayed bridges

This study addresses the critical need to understand the seismic behavior of cable-stayed bridges under Multi-Support Excitation (MSE) in order to mitigate earthquake-induced damage to these structures. The primary focus is on the investigation of response amplification phenomena and their seismic implications for cable-stayed bridges. Through a detailed comparative analysis of MSE and Synchronous Excitation (SE) across various structural locations, the study evaluates the impact of site-specific recorded ground motions of different earthquake categories. A pragmatic framework is developed to simulate realistic MSE ground motions for diverse earthquake scenarios, emphasizing the necessity of considering MSE in bridge design. The findings reveal a significant amplification of the design requirements due to antisymmetric mode excitation and increased tower and pier motions. The study also identified the need for in-depth analysis of cable-stayed bridges to address the increased vulnerability of tower-adjacent areas and to devise targeted reinforcement strategies of vulnerable components. These insights are critical for advancing seismic design practices and improving the resilience of cable-stayed bridges, contributing to safer urban infrastructure.

Research on Operation Characteristics of Passive Containment Heat Removal System in Typical Accident Conditions

In order to verify the feasibility of the design of the third generation of nuclear power plant independently developed in China, this study investigated the operation characteristics of the passive containment heat removal system under five working conditions using the passive containment heat removal system general performance verification facility: the design conditions, low water level conditions, low pressure conditions in the containment, extreme accidents conditions and resistance increasing conditions are analyzed, and the thermal characteristics, power requirements and thermal parameters of the containment under different operating conditions are analyzed. The results show that the heat dissipation capacity of the passive containment heat removal system exceeds the design requirements under the design conditions. Under off-design low pressure conditions, the pressure in the system is significantly affected. The decrease in the cooling water tank’s water level not only did not adversely affect the operation of the system but instead led to a significant increase in the system’s heat dissipation power. In the case of extreme accidents, the system may initially stall, but a stable natural cycle can then be established. As the system resistance coefficient increases, the heat dissipation power of the passive containment heat removal system exhibits an approximate linear decreasing trend.

Research on the application of AHP-FAST-FBS in the design of home entrance disinfection devices in the post-pandemic era

With the outbreak and continued spread of the COVID-19 pandemic, people's demand for daily disinfection products has increased rapidly, and its innovative design has received widespread attention. In this context, this study aims to propose a design methodology for home entrance disinfection devices based on AHP-FAST-FBS. Firstly, the design requirements of the home entrance disinfection device were collected and analyzed through in-depth interviews and the KJ method, and a hierarchical model of design demand indicators was constructed. Secondly, the Analytical Hierarchy Process (AHP) was employed to quantify these design demand indicators, and core design demands for home entrance disinfection devices were identified by weight calculations. On this basis, the Functional Analysis System Technique (FAST) method was combined to rationally transform the design demands into product functional indicators, constructing a functional system model for the home entrance disinfection device through systematic decomposition and categorization. Lastly, based on the Function-Behavior-Structure (FBS) theoretical model, the mapping of each function of the product to its structure was realized, the product structure modules were determined, and the comprehensive design and output of the innovative design scheme for the home entrance disinfection device were completed. The results of this study indicate that the design methodology combining AHP-FAST-FBS can effectively improve the scientific rigor and effectiveness of the home entrance disinfection device design, thereby generating an ideal product design scheme. This study provides systematic theoretical guidance and practical reference for designers of subsequent related disinfection products and also offers a new path for improving social health and safety.

Ridged Apertures for LEO Direct Radiating Arrays in Ka-Band

This paper presents an extensive performance analysis of open-ended waveguide elements for direct radiating arrays with a high scan angle (±50° /60°). The evaluated designs are based on square and hexagonal apertures loaded with ridges. Both square and triangular lattices are considered in the framework of Ka-band downlink design requirements for future LEO mega-constellations. The parameter space defined by the monomodal condition has been explored to find an optimum value for each structure. The analyses carried out with both infinite and finite full-wave models in terms of active reflection coefficient, scan loss and cross-polar discrimination are in good agreement.

Numerical study on the forward and inverse problems of the mobile pump truck frame

Aiming at the requirements of strong mobility and high flexibility of rescue and relief mobile pump trucks, this paper designs a new type of mobile pump truck frame based on existing mobile vehicle frame models. The materials used for the frame are 40Cr and Q235, and the finite element method is utilized to carry out static mechanical analysis and dynamic characteristic analysis. Simultaneously utilizing topology optimization and multi-objective genetic algorithm to optimize the design of the frame structure. The results show that the optimized pump truck frame can meet the strength design requirements of four typical working conditions: full load bending, full load torsion, emergency turning and emergency braking, while avoiding resonance phenomena caused by road surface and diesel engine vibration. Compared with the original frame model, the weight of the optimized frame is reduced by 87.88 kg, with a weight reduction rate of 10.89%, realizing the lightweight design requirements.

A novel rigidizable inflatable lunar habitation system: design concept and material characterization

Constructing lunar bases is crucial as lunar missions progress towards utilization and exploitation. The challenging lunar environment, with its unique characteristics and limited resources, requires special materials, structures, and construction methods. Inflatable structures offer great potential for lunar construction due to their advantages in transportation, stowage, construction, and reliability. This paper proposes a rigidizable inflatable lunar habitat that maintains its shape even after air leakage, enhancing safety, durability, and fixability. The membrane material adapts to different requirements during transportation, construction, and service, achieved through solid-state actuation of shape memory polymer (SMP) for stiffness variation, allowing multiple moves and ground tests. This work comprises three parts: 1) system: design concept and construction processes, 2) material: design and characterization of restraint and rigidization materials, and 3) structure: numerical validation of structure properties. Finite element analysis, based on material models obtained through dynamic mechanical analysis (DMA) and tensile tests, demonstrates the effectiveness of including an SMP rigidization layer in preventing collapse and enhancing dynamic properties. This paper not only proposes a new system, but also provides material design methods and requirements, along with structural validation techniques. Findings validate the feasibility of rigidizable inflatable lunar habitats, applicable in extreme environments, also in temporary buildings, space structures, and soft robotics.

Development Strategy Management Model for Tennis Club in Guangzhou City, the People’s Republic of China

Background and Aim: More tennis players in Guangzhou offer a larger platform for the sport's growth. The Guangzhou Tennis Club has grown quickly in the last few years. However, as the tennis club has grown, several issues have emerged, including management, staffing, and club operations. Materials and Methods: This study used a questionnaire to look into 286 club members, 143 club coaches, and 53 club administrators from 50 tennis clubs in Guangzhou. The data is analyzed using the descriptive statistics method, and the resultant conclusion serves as a foundation for guidance for the Guangzhou Tennis Club's strategic management model. The instrument; (1) Survey data questionnaire for research purposes. (2) Evaluation form for focus groups. (3) Expert interview guide. (4) Questionnaire for expert assessment. Analyzing Data: (1) The average and percentage must be used in the questionnaire. (2) Content analysis will be used to analyze the data from focus groups and interviews. Results: (1) Able to fully mobilize resources to support development; good at forging cooperative relationships with pertinent institutions. (2) There are organizations to support the growth of the tennis club, and the staff management structure is well-defined. (3) There are standards and design requirements for both members and staff to meet to enter the club. Issues and challenges: (1) Absence of strategies to encourage tennis club growth in conjunction with pertinent institutional or national policies. (2) Professional staff is absent from tennis club management and instruction, and the clubs' development trajectory is unidirectional. (3) Absence of a system for tracking tennis club performance and lack of authority over the maximum number of members. And (4) abusing the tennis club welfare allowance, pressuring staff members. Conclusion: (1) Guangzhou Tennis Club should be taken into consideration when creating the phased development plan, and national and government policies should be used to promote development. The organizing section's management development strategy can be summed up as follows: using the organization's current resources to support the club's quick development. The leading development strategy should be summed up in the leadership section as follows: suitable systems should be developed to standardize each employee's daily work and have requirements for employees. The following succinctly describes the controlling development strategy in the control section: planning employee development and effectively ensuring employee welfare, as well as collaboratively advancing the growth of Guangzhou Tennis Club. (2) Fifteen experts have given the Guangzhou Tennis Club's development strategy management mode, which was created for this study, high marks. The Guangzhou Tennis Club's development strategic management mode received an average score of 4.65 from 15 participants, indicating that the experts are satisfied with the mode's practical application and overall impact.

Form-finding of tensegrity structures based on graph neural networks

Tensegrity structures, characterized by enhanced stiffness, slender struts, and superior buckling resistance, have found wide-ranging applications in fields such as engineering, architecture, art, biology, and robotics, attracting extensive attention from researchers. The form-finding process, a critical step in the design of tensegrity structures, aims to discover the self-equilibrated configuration that satisfies specific design requirements. Traditional form-finding methods based on force density often require repeated steps of eigenvalue decomposition and singular value decomposition, making the process complex. In contrast, this paper introduces a new intelligent form-finding algorithm that uses the force density method and combines the Coati optimization algorithm with Graph Neural Networks. This algorithm avoids the complex steps of eigenvalue and singular value decomposition and integrates the physical knowledge of the structure, making the form-finding process faster and more accurate. In this algorithm, various force densities are initially randomized and input into a trained Graph Neural Networks to predict a fitness function’s value. Through optimizing the constrained fitness function, the algorithm determines the appropriate structural force density and coordinates, thereby completing the form-finding process of the structure. The paper presents seven typical tensegrity structure examples and compares various form-finding methods. The results of numerical examples show that the method proposed in this paper can find solutions that align with the super-stable line more quickly and accurately, demonstrating its potential value in practical applications.

Blended-Wing-Body Regional Aircraft Optimization with High-Fidelity Aerodynamics and Critical Design Requirements

Conventional tube-and-wing and proposed blended-wing-body airliners must satisfy several design requirements, but the latter configuration is tightly integrated and sensitive to these requirements. In this work, blended-wing-body regional aircraft are investigated using a gradient-based mixed-fidelity multidisciplinary optimization framework centered on a Reynolds-averaged Navier–Stokes solver. In addition to sizing and cruise trim, design requirements considered include one-engine-inoperative directional trim, takeoff rotation ability, takeoff field length, initial climb performance, low-speed trim and static margin, and top-of-climb rate of climb. Results show how optimal design features vary and performance is overpredicted if critical design requirements are excluded and how key elements of geometric freedom help realize the potential of the configuration. A 4.8% block fuel burn benefit is enabled by pivot-piston variable-length landing gear even with low-mounted engines and high design freedom. The off-design constraints penalize block fuel burn by 3.2% if variable-length landing gear is considered, but this value reaches 7.6% if lower geometric freedom that inhibits tight cabin contouring and the formation of a novel forebody ridge is removed. Leading-edge carving is found to be optimal. The high design freedom and high-fidelity aerodynamics model help efficiently satisfy the design requirements, resulting in a cruise lift-to-drag ratio of 21.7 at 36,000 ft and Mach 0.78.