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The purpose of this study is to calculate the normal force of a two degree of freedom direct drive induction motor considering coupling effects based on an analytical model. Compared with the traditional single degree of freedom motor, normal force characteristics of two-degree-of-freedom direct drive induction motor (2DOFDDIM) is affected by coupling effect when the machine is in a helical motion. To theoretically explain the influence mechanism of coupling effect, this paper conducts a quantitative analysis of the influence of coupling effect on normal force based on the established analytical model of normal force considering coupling effect.

Firstly, the normal forces generated by 2DOFDDIM in linear motion, rotary motion and helical motion are investigated and compared to prove the effect of the coupling effect on the normal force. During this study, several coupling factors are established to modify the calculation equations of the normal force. Then, based on the multilayer theoretical method and Maxwell stress method, a novel normal force calculation model of 2DOFDDIM is established taking the coupling effect into account, which can easily calculate the normal force of 2DOFDDIM under different motions conditions. Finally, the calculation results are verified by the results of 3D finite element model, which proves the correctness of the established calculating model.

The coupling effect produced by the helical motion of 2DOFDDIM affects the normal force.

In this paper, the analytical model of the normal force of 2DOFDDIM considering the coupling effect is established, which provides a fast calculation for the design of the motor.

Collaborative research and development have remained a pertinent mechanism for conducting technological innovations. With the lens of knowledge-based view (KBV), this study aims to examine the role of changes in knowledge couplings and network cohesion to elevate innovation performance.

Data analysis has been performed on 53,459 patents through regression analysis with random effects. These independent and joint patents are extracted from Derwent Innovation Database.

Findings explicate that change in external existing or existing and new knowledge couplings have inverted U-shaped effects on a firm’s innovation performance. Changes in internal existing or existing and new knowledge couplings have direct positive effects on firm’s innovation performance. The moderation effect of network cohesion flattens the inverted U-shaped effect of external new and existing knowledge coupling, whereas it has no significant effect on external existing knowledge coupling. Network cohesion further elevates the effects of internal knowledge couplings – existing or existing and new.

This study theoretically contributes to KBV and innovation management literature by highlighting the scope of changes in internal and external knowledge couplings and subsequent output. Network cohesion flattens the curviness of changes in external new and existing knowledge couplings, which is a contribution to strategic management literature.

Organizations need to carefully manage changes in knowledge couplings and ensure their benefits (obtain new knowledge domain or new combination) outweigh liabilities (damages to organizational routines or increase in collaboration costs). Managers must consider four kinds of knowledge coupling changes along with developing network cohesion as an R&D strategy.

This study is one of its types to flatten the curve through network cohesion. This study divided the changes in knowledge coupling into four types and two dimensions; external existing and new and existing knowledge couplings and internal existing and new and existing knowledge couplings.

The purpose of this research paper is to analyze the combined effects of driver size and coupling parasitics on crosstalk noise and delay for static and dynamically switching victim line. Furthermore, this paper shows the effect of inductance on delay and qualitatively optimizes its value to obtain minimum delay.

The interwire parasitics are the primary sources of crosstalk or coupled noise that may lead to critical delays/logic malfunctions. This paper is based on simulating a pair of distributed resistance inductance capacitance (RLC) interconnects coupled capacitively and inductively for measurements of crosstalk noise/delay. The combined effects of driver sizing and interwire parasitics on peak overshoot noise/delay are observed through simulation program with integrated circuit emphasis (SPICE) simulations for different switching patterns. Furthermore, the analysis of inductive effect on propagation delay as a function of coupling capacitance is carried out and the optimization of delay is worked out qualitatively. The simulations are carried out at 0.13 μm, 1.5 V technology node.

This paper observes the contradictory effects of coupling parasitics on wire propagation delay; however, the effect on peak noise is of a different kind. Further, this paper shows that the driver size exhibits opposite kind of behavior on propagation delay than peak over shoot noise. It is observed that the delay is affected in presence of inductance; thus, the optimization of delay is carried out.

The effects of driver sizing and interwire parasitics are analyzed through simulations. The optimum value of coupling capacitance for delay is found qualitatively. These findings are important for designing very large scale integration (VLSI) interconnects.

Through empirical research, this study aims to explore the role of competition and cooperation in coupling open innovation (OI).

In this study, the hierarchical regression analysis method was used to test each hypothesis.

Cooperation has an inverted U-shaped moderating effect between coupling OI and innovation performance. Competition negatively moderates the relationship between inbound-oriented coupling OI and innovation performance, and has an inverted U-shaped moderating effect between outbound-oriented coupling OI and innovation performance. When competition and cooperation coexist, competition will passivate the moderating effect of cooperation between inbound-oriented coupling OI and innovation performance, and sharpen the moderating effect of cooperation between outbound-oriented coupling OI and innovation performance.

The role of competition and cooperation on different types of coupled innovation is studied for the first time. This research greatly enriches the theory of the effect of innovation network on innovation performance.

Using the industrial data between 2000 and 2016, this study analysed the process of coupling and coordinated development of technological innovation and standardisation. Accordingly, the study considered the high-tech industry (five sub-sectors) in China as the research object.

Based on the summary of innovation and standardisation literature review, this study constructed a theoretical model of the influence of technological innovation and standardisation on industrial development from the perspective of the coupling system. Furthermore, the study employed multivariate linear regression analysis to explore coupling coordination relationships.

The study results revealed that high coupling coordination between technological innovation and standardisation is highly conducive to industrial development. Moreover, requirements for standardisation levels differ owing to different stages and characteristics in each segmented industry.

This study primarily contributes to the literature by using a bibliometrics tool to summarise related literature on innovation and standardisation and provides a new perspective of reviewing, and it also offers new evidence on the coupling coordination relationship between innovation and standardisation in the high-tech industry.

The purpose of this study is to investigate the coupling effects of the velocity slip, rarefaction effect and effective viscosity of the gas film on the performance of the aerostatic guideway in micro-scale and improve the analysis precision of the static performance of aerostatic guideway.

The corresponding model of the gas film flow with consideration of the velocity slip, rarefaction effect and effective viscosity of the gas film in micro-scale is proposed. By solving the corresponding model, the bearing capacity and the stiffness of the aerostatic guideway are obtained through the pressure distributions of the air cavity. Through comparing the bearing capacity and the stiffness in different situations, the couple effects of the three factors are analyzed. Finally, the experimental results about the stiffness are obtained and the contrast between the simulation stiffness and the tested stiffness is achieved.

Through comparing the coupling effects of the micro scale factors under different conditions on the performance of the aerostatic guideway, it was found that when comparing the effects of a single factor, the effect of the first-order slip is the largest. When two factors are randomly combined, velocity slip and viscosity of the gas film is the largest, but these coupling effects are less than the effect of considering three factors simultaneously.

It is essential to consider the first-order velocity slip, the flow factor Q and the effective viscosity when analyzing the static performance of the aerostatic guideway in micro-scale. This makes studying the performance of the aerostatic guideway in micro-scale feasible and improves the machine’s accuracy.

The purpose of this paper is to investigate the influence of end‐effect and cross‐coupling on the torque‐speed characteristics of switched flux permanent magnet (SFPM) machines.

The torque‐speed characteristics are predicted using two different methods. These are direct and indirect finite element methods, at different cross‐coupling levels, namely, full cross‐coupling on both PM flux linkage and dq‐axis inductances, partial cross‐coupling on the PM flux linkage only and without cross‐coupling.

The influence of the cross‐coupling on dq‐axis inductances of the studied machine is relatively small. However, it is more significant on the PM flux linkage. Therefore, the partial cross‐coupling model, which is much easier and faster, exhibits almost the same accuracy as the full cross‐coupling model. Furthermore, the end‐effect causes a large reduction in torque‐speed characteristics. However, such a reduction is more significant in the flux weakening operation region.

This is the first time that the influence of end‐effect of SFPM machines on the torque‐speed characteristics, especially in flux weakening region, and on the dq‐axis inductances has been investigated.

The purpose of this paper is to attempt to realize a complete analysis at scenario deduction of unconventional incidents coupling based on the GERTS network method.

Starting from the manifestation of coupling objects, three types of emergency coupling are analyzed according to different rules, which are “events‐events” coupling, “event‐factors” coupling and “factors‐factors” coupling. Then the coupling mechanism for emergency is focused on analyzing, and the concepts of three types of coupling are put forward, at the same time, three quantitative models for coupling mechanisms are present. Also, a case was discussed to verify the analysis of coupling mechanism of emergency.

According to the types of factors rules, the classes of coupling of emergency have been divided into three types. The coupling mechanism of emergency can be used to describe the novel coupling models.

This research provides the method for coupling analysis in the scenario of unconventional incidents and guides the emergency managers to develop contingency strategies.

The paper succeeds in constructing a novel coupling model for emergency, and it could provide an effective tool for a quantitative study on unconventional incidents coupling.

Highly anisotropic zirconium is a material used in the cladding of nuclear fuel rods, ensuring containment of the radioactive material within. The complex material structure of anisotropic zirconium requires model developers to replicate not only the macro-scale stresses but also the meso-scale material behavior as the crystal structure evolves; leading to strongly coupled multi-scale plasticity models. Such strongly coupled models can be achieved through partitioned analysis techniques, which couple independently developed constituent models through an iterative exchange of inputs and outputs. Throughout this iterative process, biases, and uncertainties inherent within constituent model predictions are inevitably transferred between constituents either compensating for each other or accumulating during iterations. The paper aims to discuss these issues.

A finite element model at the macro-scale is coupled in an iterative manner with a meso-scale viscoplastic self-consistent model, where the former supplies the stress input and latter represents the changing material properties. The authors present a systematic framework for experiment-based validation taking advantage of both separate-effect experiments conducted within each constituent’s domain to calibrate the constituents in their respective scales and integral-effect experiments executed within the coupled domain to test the validity of the coupled system.

This framework developed is shown to improve predictive capability of a multi-scale plasticity model of highly anisotropic zirconium.

For multi-scale models to be implemented to support high-consequence decisions, such as the containment of radioactive material, this transfer of biases and uncertainties must be evaluated to ensure accuracy of the predictions of the coupled model. This framework takes advantage of the transparency of partitioned analysis to reduce the accumulation of errors and uncertainties.

The purpose of this paper is to analyze the effect of the space thermal effect on satellite antenna.

In this paper, according to the geometric characteristics of parabolic reflector, the transient temperature field of an element along its thickness direction is built for shell structures using finite element discretization and the quadratic function interpolation, and heat conduction equations are derived based on the theory of the thermo-elastic dynamics. The modeling theory of rigid–flexible coupling system considering thermal effect is extended to the satellite antenna system. Then, the coupling dynamic equations are established including coupling stiffness matrix and thermal loaded undergoing a large overall motion. Finally, an adaptive controller is proposed and the adaptive update laws are designed under the parameter uncertainty.

The results of dynamic characteristic analysis show that the dynamic thermal loaded coupled with structure deformation induce the unstable vibration and coupled flutter. Further, the coupling effect degrades the antenna pointing accuracy seriously and leads to disturbances on satellite base. The results of the simulation show that the adaptive controller can ensure that antenna pointing closes to the expected trajectory progressively, and it demonstrates that the proposed control scheme is feasible and effective.

The paper considers only the effect of space thermal effect to satellite antenna. Further research could be done on the flexible multibody system by considering joint clearance in the future research.

The conclusions of this paper would be an academic significance and engineering value for the analysis and control of satellite antenna pointing.