Traditional Design Theory Research Articles

USING PLEASURABILITY TO COMPARE WRISTWATCHES AND IOT SMARTWATCHES: PROVIDING NOVEL INSIGHTS INTO UX DESIGN

AbstractThe emergence of the Internet of Things (IoT) has brought more challenges for designers to fully understand networked objects and develop pleasurable user experiences (UXs). Due to the radical change of products when they are connected, traditional experience design theories may not be applicable in this new context. Based on two well-established UX design theories, this paper presents a survey study that investigated the pleasurability of IoT devices by comparing a representative IoT device (i.e., the smartwatch) and its conventional form (i.e., the wristwatch). An online questionnaire was deployed to gather feedback from parallel wristwatch and smartwatch users. Their experiences using both types of watches were quantitatively and qualitatively compared by data analysis. The results highlighted the differences in UXs between smartwatches and wristwatches in three types of pleasure and five psychological needs. The study revealed design opportunities to improve the pleasurability of smartwatches and provides novel design insights informing the development of pleasurable UXs for future IoT devices.

Multi-Objective Optimization Strategy for Permanent Magnet Synchronous Motor Based on Combined Surrogate Model and Optimization Algorithm

When a permanent magnet synchronous motor (PMSM) is designed according to the traditional motor design theory, the performance of the motor is often challenging to achieve the desired goal, and further optimization of the motor design parameters is usually required. However, the motor is a strongly coupled, non-linear, multivariate complex system, and it is a challenge to optimize the motor by traditional optimization methods. It needs to rely on reliable surrogate models and optimization algorithms to improve the performance of the PMSM, which is one of the problematic aspects of motor optimization. Therefore, this paper proposes a strategy based on a combination of a high-precision combined surrogate model and the optimization method to optimize the stator and rotor structures of interior PMSM (IPMSM). First, the variables were classified into two layers with high and low sensitivity based on the comprehensive parameter sensitivity analysis. Then, Latin hypercube sampling (LHS) is used to obtain sample points for highly sensitive variables, and various methods are employed to construct surrogate models for variables. Each optimization target is based on the acquired sample points, from which the most accurate combined surrogate model is selected and combined with non-dominated ranking genetic algorithm-II (NSGA-II) to find the best. After optimizing the high-sensitivity variables, a new finite element model (FEM) is built, and the Taguchi method is used to optimize the low-sensitivity variables. Finally, finite element analysis (FEA) was adopted to compare the performance of the initial model and the optimized ones of the IPMSM. The results showed that the performance of the optimized motor is improved to prove the effectiveness and reliability of the proposed method.

Modeling and optimization of longitudinal-torsional vibration horn with the large tool head

There are problems such as large deviations in resonant frequency and difficulties in selecting the structural parameters of helical slot when designing longitudinal-torsional vibration horn with large tool head (HWLTD) using traditional design theory of horn. Therefore, in this paper, HWLTD was designed integrally, the model of HWLTD was established, longitudinal vibration frequency equation of HWLTD was derived and consequently, the resonant frequency was predicted and optimized. Then, the principle of vibration mode transformation (POVMT) of helical slots was derived. Combined with POVMT and ANSYS simulation analysis, resonant frequency and torsional-longitudinal ratio of longitudinal-torsional vibration of HWLTD were optimized, thereby improving the vibration characteristics of HWLTD. The resonant frequency and vibration effect of HWLTD were tested, and the measurements were agreed with the theoretical design and simulation analysis, which validates the HWLTD model and POVMT. The research provides a reference for the efficient and reliable design of HWLTD in the field of ultrasonic machining.

Investigation of the influence of blade configuration on the hemodynamic performance and blood damage of the centrifugal blood pump.

The design and optimization of centrifugal blood pumps are crucial for improved extracorporeal membrane oxygenation system performance. Secondary flow passages are common in centrifugal blood pumps, allowing for a high volume of unstable flow. Traditional design theory offers minimal guidance on the design and optimization of centrifugal blood pumps, so it's critical to understand how design parameter variables affect hydraulic performance and hemocompatibility. Computational fluid dynamics (CFD) was employed to investigate the effects of blade number, blade wrap angle, blade thickness, and splitters on pressure head, hemolysis, and platelet activation state. Eulerian and Lagrangian features were used to analyze the flow fields and hemocompatibility metrics such as scalar shear stress, velocity distribution, and their correlation. The equalization of frictional and flow losses allow impellers with more blades and smaller wrap angles to have higher pressure heads, whereas the trade-off between the volume of high scalar shear stress and exposure time allows impellers with fewer blades and larger blade wrap angles to have a lower HI; there are configurations that increase the possibility of platelet activation for both number of blades and wrap angles. The hydraulic performance and hemocompatibility of centrifugal blood pumps are not affected by blade thickness. Compared to the main blades, splitters can improve the blood compatibility of a centrifugal blood pump with a small reduction in pressure head, but there is a trade-off between the length and location of the splitter that suppresses flow losses while reducing the velocity gradient. According to correlation analysis, pressure head, HI, and the volume of high shear stress were all substantially connected, and exposure time had a significant impact on HI. The platelet activation state was influenced by the average scalar shear stress and the volume of low velocity. The findings reveal the impact of design variables on the performance of centrifugal blood pumps with secondary flow passages, as well as the relationship between hemocompatibility, hydraulic performance, and flow characteristics, and are useful for the design and optimization of this type of blood pump, as well as the prediction of clinical complications.

The air distribution and flow resistance of tuyeres with coupling effect

The tuyere plays a critical role in creating a comfortable the indoor environment and is significant for the obtaining hydraulic balance in ventilation and air condition (VAC) systems. Currently, the internal flow state of the tuyeres in VAC duct engineering design is idealized for full development. Ignoring the coupling effect causes the problem of ineffective air distribution and places an enormous load on the entire system. Therefore, the deviation in the air distribution and the change in the flow resistance of circular diffusers and spherical nozzles under the coupling effect are studied through full-scale experiments and numerical simulations. In this research, the deviation law under coupling effect conditions is presented, and the relative deviation formula of the circular diffuser under the coupling effect is fitted. Considering the total pressure loss, relative deviation, and target value, a table that shows connection approaches in engineering applicable to circular diffusers is proposed. The reduced structure of the spherical nozzle overcomes the disturbance caused by the coupling effect but increases the resistance by approximately 50.8%. Consequently, the research results from the study of tuyeres under the coupling effect are expected to lead to a reduction in unnecessary energy consumption and supplement the traditional design theory of the VAC duct system.

ANALYSIS AND THINKING ON STRUCTURAL PERFORMANCE EVOLUTION OF SHIELD TUNNEL LINING

Under the background of China's strategy to strengthen transportation industry, the mechanical performance and durability of shield tunnel ling face higher requirements with the increasing construction of ultra-long, large cross-section, deep buried and high-density developed shield tunnels. In this paper, the traditional shield tunnel structure design theory and method and the current development trend are summarized based on an extensive investigation of domestic and foreign literatures. And the status quo and shortage of researches on shield tunnel structure’s mechanical property and durability are discussed, the current shield tunnel structure performance detection technology and evaluation methods are further reviewed. In view of the limitations of the traditional reinforced concrete segment, the (steel) fiber concrete material, the new joint and the compression concrete lining have great advantages in improving the structural performance and construction efficiency of shield tunnel lining, which are the future development direction of shield tunnel lining structures.

Key Technology and Experimental Study of Unequal Pitches Meshing between Metal Worm and Plastic Helical Gears

In traditional gear design, the design theory is based on a rigid hypothesis and is popularly adopted in the preparation of metal gear. Plastic gear designing lacks a mature design theory. Hence, scholars still follow the traditional gear design theory. There is a marked difference in the rigidity and stiffness between the conventional gear design and plastic gear features. In traditional design theory, the deformation is 0.2% (Note: To assess the material yield, conditional yield strength is calculated). Designing deformation can exceed 2% for plastic gears, and the difference can sometimes be more than tenfold. The traditional design theory cannot match the gear strength and precision in the design of plastic gear. In the case of plastic gear, due to numerous meshing teeth, the 2% deformation seen cannot be neglected and should be taken into account in the presence and absence of loading to improve the meshing condition. Improvement in the gear loading ability and reduction in the meshing noise can thus be achieved. Herein, we propose an unequal pitch design theory. The results of Finite Element Analysis (FEA) and experimental verification showed that the strength could be increased by 24% for unequal pitch design theory.

Structural analysis of a large aluminum alloy truss double-arch bridge

In recent years, aluminum alloy bridges have been constructed in China, but a lack of aluminum alloy design and construction standards limits their further development. Traditional concrete and steel design theory cannot be completely adopted for aluminum alloy in large bearing structures. To introduce the structural design of a two-span continuous aluminum alloy truss arch bridge, this paper describes the material type, section design, component connections and bridge bearings in detail. Deflection and stress under live load are analyzed by means of a finite-element model to prove that the allowable deformation can be much greater than L/800 due to low stress in the members. Additional flexural stress subject to large eccentricity cannot be neglected, and the allowable joint eccentricity is proposed as 5% of the section height of the upper or lower chord, or about 15.0 mm. As a result of large ratio of live load to dead load, aluminum alloy footbridges reveal a rapid drop in frequency and pedestrian comfort when pedestrian mass is considered in the vibration analysis. Aluminum alloy footbridges are more sensitive to pedestrian mass than steel footbridges, and the comfort evaluation considering pedestrian mass is very necessary in design. Elastic buckling results reveal that steel and aluminum alloy footbridges have similar buckling modes, while aluminum alloy footbridges have lower buckling eigenvalue and ultimate bearing capacity. Furthermore, nonlinear buckling analysis of bridges is used to identify vulnerable members and improve structural stability by strengthening the local members. As a result, four rows of additional diagonal members near the middle pier were installed, and the elastic and nonlinear buckling bearing capacities reached 2.67 and 2.89 times the design pedestrian load, respectively. The additional diagonal web members were proved to play a significant role in increasing structural stability and evenly distributing the pedestrian load.

A computer-aided approach improving the Axiomatic Design theory with the distributed design resource environment

AbstractIn the traditional Axiomatic Design (AD) theory, the mapping from the functional domain to the physical domain is based on the designers’ own knowledge and experience, and there is no systematical approach including the design resources provided outside the designers themselves’ access. Thus, the raw materials for the design process are largely limited, which means they can hardly support the designers’ increasingly creative and innovative conceptions. To help AD theory better support the design process, this paper proposes a computer-aided approach for the mapping from the functional domain to the physical domain within a distributed design resource environment, which consists of numerous design resources offered on the Internet by the providers widely distributed in different locations, institutes, and disciplines. To prove the feasibility of this proposed approach, a software prototype is established, and a natural leisure hotel is designed as an implementation case.

Wideband circularly polarised patch antenna with multi‐section λ/4 transmission lines

A wideband circularly polarised patch antenna with multi-section λ/4 transmission lines is proposed. The multi-section lines are directly connected to the patch radiator. The feeding circuit and patch are on the same layer, which makes it easy for integration. There is no coupling structure, and consequently, the parasitic radiation from the feeding circuit can be minimised. The whole antenna structure is designed according to the traditional filter design theory. Two minima in the axial ratio response come up to achieve wideband characteristic. Finally, the proposed antenna structure and wideband performances are experimentally verified by an antenna prototype.

Multiobjective Optimization Design of a Double-Rotor Flux-Switching Permanent Magnet Machine Considering Multimode Operation

The multimechanical-port double-rotor machine, as a core component in hybrid electric vehicles, has attracted considerable attention due to the merits of compact structure, control flexibility, and diverse performances. However, since there often exist two electric or mechanical ports in one compound machine frame, traditional design theory cannot be applied to it directly. Besides, because of the relatively complex machine structure and multiple design parameters, design objectives often influence even conflict with each other. In this paper, a new multiobjective optimization design approach is proposed to design and optimize a flux-modulated double-rotor flux-switching permanent magnet machine, where multiple driving modes are considered. To verify the feasibility of the double-rotor machine and the effectiveness of an optimization design method, the electromagnetic characteristics of the machine are investigated in detail. Finally, a prototype machine is built and tested. Both theoretical analysis and experimental results verify the validity of the proposed machine and multiobjective optimization design approach.

The Dynamics of Architectural Form: Space, Emotion and Memory

The focus of this paper is in the area of architectural psychological impacts on human senses, behaviours and experiences. Such a study is important and essential in order to unite the senses, feelings and experiences together with the traditional architectural design theories and methods, and then understand how we should design and what we should concern about during design. This paper summarises an approach for architectural design on how to integrate multi-senses into practice and reflect human senses, behaviours and experiences in the realm of environmental psychology. This paper also recommends that architects should be aware of these psychological influences for future design; a consideration of environmental perception and responses should be taken during interior design, architectural design and urban planning.

Customer value development in the light of design thinking approach

Purpose: The aim of this study is to ascertain the meaning and characteristics of the entrepreneurs’ empathy as the most signifi cant approach for modern business and its role in design thinking methodology, where empathy is used for multiple purposes. Methodology: Literature review on design thinking approach and objectives, empathy and customer value development as well as abstract modelling and synthesis is the methodology of this study. Findings: Content analysis shows that among the many approaches and defi nitions of the entrepreneurs’ empathy to the customers, none directly points the role of design thinking in ensuring customer value development. There has been a conceptual transition to integrated conceptualization of design thinking, which allows the theoretical assumptions to move beyond traditional design practices and theories, and there is a potential for new design approaches focused on customer experience that promote customer and business value. Originality/value: The novelty of this study is a presentation of meaning and characteristics of the entrepreneurs’ empathy, its role in design thinking approach, as well as development models which both refer to the value for customers and business. The author proposes a new approach and conceptual framework for design thinking process in order to promote solutions which allow to build a new customer value by entrepreneurs.

Product Data Model for Performance-driven Design

When designing large-sized complex machinery products, the design focus is always on the overall performance; however, there exist no design theory and method based on performance driven. In view of the deficiency of the existing design theory, according to the performance features of complex mechanical products, the performance indices are introduced into the traditional design theory of “Requirement-Function-Structure” to construct a new five-domain design theory of “Client Requirement-Function-Performance-Structure-Design Parameter”. To support design practice based on this new theory, a product data model is established by using performance indices and the mapping relationship between them and the other four domains. When the product data model is applied to high-speed train design and combining the existing research result and relevant standards, the corresponding data model and its structure involving five domains of high-speed trains are established, which can provide technical support for studying the relationships between typical performance indices and design parameters and the fast achievement of a high-speed train scheme design. The five domains provide a reference for the design specification and evaluation criteria of high speed train and a new idea for the train’s parameter design.

Design criterion involving comprehensive performance characteristics of nozzle–flapper valves

The traditional parameter design rule for the nozzle–flapper valves has always followed the maximum control pressure sensitivity criterion; however, this article queries the validity of this traditional parameter design theory for the comprehensive performance characteristics of a flapper–nozzle valve. Accordingly, a new parameter design rule, which involves symmetry, linearity and sensitivity of the control pressure, was constructed from a detailed and rigorous mathematical derivation that employs a non-dimensional analysis method. Then, an effect verification of the new criterion and a comparison between the pressure–flow curves and three key valve coefficients, which are dominated by the traditional rule and the new criterion, respectively, are performed. Finally, the comprehensive performance characteristics of the flapper–nozzle valve, such as the reliability, response, accuracy, sensitivity, efficiency, anti- disturbance and control pressure range, which are produced by the two parameter design rules, are compared. The results indicate that the performance of nozzle–flapper valve followed by the new parameter design criteria is superior to the performance directed by the traditional one with respect to various indexes, such as the reliability, response, accuracy and anti-disturbance. In addition, for the design of nozzle–flapper valves, the studies have also revealed that the optimal values of the structural parameter are dependent on the actual flapper motion ranges and the priority of the above-mentioned performance indexes. All these new findings can develop and supplement the existing design theory of nozzle–flapper valve and can also be beneficial to the design of double-nozzle–flapper electro-hydraulic servo valves.

Building better learning and learning better building, with learners rather than for learners

PurposeThe purpose of this paper is to describe the relevant role of users/learners as designers/creators of meaningful and effective learning places and spaces in both digital and virtual worlds.Design/methodology/approachThe paper is based on research and observation of changing trends in users' behavior in physical and digital collaborative workplaces and spaces all over the world.FindingsIn this third millennium, the new spirit of knowmadic workers and learners is breaking down old design concepts and rules. The progressively more subtle frontier between virtual and physical learning environments and working environments is changing the use by, and the behavior of, learners in these places and spaces. In this context, the transversal‐thinking, designer‐guided paradigm is rendered effectively useless. The era of user‐led design has started. User‐oriented design is an old trend; it has changed over time. In societies and economies based on learning, reflection and constant collaboration, the individualistic design guru has no place.Originality/valueThis paper discusses the evolving strategic role of users/learners as designers and co‐creators of their own places. Traditional design criteria and theories are outdated. The role of the designer as master/creator is not compatible with the collegiate and collaborative, reflective spirit of knowmadic learners. A consequence is a requirement for new strategies and a redefinition of the designer's role in the creation of space. The axis of design control has shifted.

The Rubber O-Ring Seal Structure Simulation Research of Electromagnetic Measurement while Drilling Instrument

The instrument of electromagnetic measurement while drilling （EM-WMD）works in the underground environment. In the case of mechanical structure design, sealing is a key problem that needs to be focused. Based on the application of using the traditional design theory to determine the sealing structure and size, finite element analysis is implemented on the rubber O-ring radial seal structure by using the nonlinear finite element software MSC.Marc. The numerical simulation is processed according to different parameters both of axis and axle sleeve gap value and seal groove fillet radius value, and then both of the influence factors of sealing effect are analyzed. Finally , based on this, the relevant seal structure size is optimized.

Research Progress of Structural Seismic Design Thought

Research progress of structural seismic design theory is analyzed and collated in this paper, including static analysis theory, theory of response spectrum, dynamic theory. The three theoretical research and design methods are analyzed and described in the paper one by one. At last, modern seismic design method which is called performance-based seismic design theory is compared and analyzed with the traditional anti-seismic design theory. Its advanced characteristics and advantages are obtained, which will be the core and development of seismic design ideas.

Quantum Mechanism Helps Agents Combat with 'Bad' Social Choice Rules

Quantum strategies have been successfully applied in game theory for years. However, as a reverse problem of game theory, the theory of mechanism design is ignored by physicists. In this paper, we generalize the classical theory of mechanism design to a quantum domain. The main result is that by virtue of quantum mechanism, agents who satisfy a certain condition can combat with 'bad' social choice rules instead of being restricted by the traditional mechanism design theory.

Study on the Transverse Load Distribution Coefficient of Different Spans of Reinforced Concrete Rigid Fame Arch Bridge

To study the effect of transverse stiffness on the mechanical behavior of reinforced concrete rigid-frame arch bridge, an integral model was set up by using the spatial finite element analysis software, four different spans rigid frame arch bridges were analyzed and the influence of transverse load distribution coefficients on different deck stiffness was studied. Compared with the results of deflection method, it shows that the transverse load distribution coefficient calculated by elastically supported continuous beam method is smaller; also, the transverse stiffness is directly related to the magnitude of transverse load distribution of the bridge and a serious difference of the forces calculated with traditional design theory, which should be modified in the design.