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Shows how methodological choices are not theoretically neutral. Draws attention to ways in which different analyses of the same data may affect inferences about teachers’ policy coupling in school systems. In this case study of the Jerusalem school system the authors used three statistical procedures to assess teachers’ perceived policy alignment among three organizational levels (teachers; schools; and the Israel Ministry of Education (IMOE)). Analyses using descriptive statistics show that the perceived policies at the three levels are similar, thus giving some support to the theory of tight coupling. Smallest Space Analysis shows that there are close connections between the teachers’ own policies and those they impute to schools, but not those they impute to the IMOE. These findings support a moderate view of organizational coupling. Finally, variance component analyses find almost no consensus in schools regarding policies. In contrast to the other approaches, these models support a loose coupling hypothesis. In overview, shows how methodological choices affect the support given to rival theoretical hypotheses. Suggests that theoretical looseness with regard to explicit falsification conditions is at the root of contrasting evidence about teacher coupling in school systems.

This study aims to investigate the impact of government support on the coupling coordination degree of innovation chain and capital chain in integrated circuit (IC) enterprises and to explore the mechanism for considering talent in the influence path.

This paper uses coupling coordination degree model to estimate the coupling of two chains, and applies dynamic panel system generalized method of moments (system-GMM) to analyze the impact of government support on coupling of two chains and conducts dynamic panel threshold regression to explore the threshold effect of talent in the influence of government support on coupling coordination degree.

Serious imbalance in the coupling of two chains is a major obstacle in IC enterprises. Government support significantly reduces the coupling coordination degree. The talent in IC enterprises has a significant threshold effect. When the number of talent is lower than the threshold value, government support has a negative impact. Once the number of talent reaches a certain level, government support can significantly enhance the coupling of two chains. Compared with state-owned enterprises, government support has a greater negative impact on the coupling of the two chains in non-state-owned enterprises. The former needs more talent to take advantage of government support.

This paper applies the concept of coupling into enterprises and deeply studies the coupling coordination degree of two chains. The influence mechanism of government support and talent on the coupling of two chains is explored, which reveals that government support cannot achieve the expected incentive effect without the support of talent. We also discuss the heterogeneous effect of government support and of talent in enterprises of different ownership types.

In this paper, a first‐order approximation coupling (FOAC) model is investigated to analyze the dynamics of the hub‐beam system, which is based on the Hamilton theory and the finite element discretization method. The FOAC model for the hub‐beam system considers the second‐order coupling quantity of the axial displacement caused by the transverse displacement of the beam. The dynamic characteristics of the system are studied through numerical simulations under twos cases: the rotary inertia of the hub is much larger than, and is close to, that of the flexible beam. Simulation and comparison studies using both the traditional zeroth‐order approximation coupling (ZOAC) model and the FOAC model shows that when large motion of the system is unknown, possible failure exists by using the ZOAC model, whereas the FOAC model is valid. When the rotary inertia of the hub is much larger than that of the beam, the result using the ZOAC model is similar to that using the FOAC model. But when the rotary inertia of the hub is close to that of the beam, the ZOAC model may lead to a large error, while the FOAC model can still accurately describe the dynamic hub‐beam system.

In traditional calibration methods of kinematics parameters of industrial robots, dozens of model parameters are identified together based on an optimization procedure. Due to different contributions of model parameter errors to the tool center point positioning error of industrial robots, obtaining good results for all model parameters is very difficult. Therefore, the purpose of this paper is to propose a sequential calibration method specifically for transmission ratio parameters, which includes reduction ratios and coupling ratios of industrial robot joints.

The ABB IRB 1410 industrial robot is considered as an example in this study. The transmission ratios for each joint of the robot are identified using the spatial circle fitting method based on spatial vectors, which fit the center and radius of joint rotation with the least squares optimization algorithm. In addition, a method based on the Rodrigues’ formula is designed and presented for identifying the actual coupling ratio of the robot. Subsequently, an experiment is carried out to verify the proposed sequential calibration method of transmission ratios.

In this experiment, the actual positions of the linkages before and after joint rotations are measured by a laser tracker. Accurate results of the reduction ratios and the coupling ratios are calculated, and the results are verified experimentally. The results show that by calibrating the reduction ratios and coupling ratios of the ABB robot, the rotation angle errors of the robot joints can be reduced.

The authors propose a sequential calibration method for transmission ratio parameters, including reduction ratios and coupling ratios of industrial robot joints. An experiment is carried out to verify this proposed sequential calibration method. This study may be beneficial for calibrating the kinematic parameters of industrial robots and improving their positioning accuracy.

Physical phenomena interact with each other in ways that one cannot be analyzed without considering the other. To account for such interactions between multiple phenomena, partitioning has become a widely implemented computational approach. Partitioned analysis involves the exchange of inputs and outputs from constituent models (partitions) via iterative coupling operations, through which the individually developed constituent models are allowed to affect each other’s inputs and outputs. Partitioning, whether multi-scale or multi-physics in nature, is a powerful technique that can yield coupled models that can predict the behavior of a system more complex than the individual constituents themselves. The paper aims to discuss these issues.

Although partitioned analysis has been a key mechanism in developing more realistic predictive models over the last decade, its iterative coupling operations may lead to the propagation and accumulation of uncertainties and errors that, if unaccounted for, can severely degrade the coupled model predictions. This problem can be alleviated by reducing uncertainties and errors in individual constituent models through further code development. However, finite resources may limit code development efforts to just a portion of possible constituents, making it necessary to prioritize constituent model development for efficient use of resources. Thus, the authors propose here an approach along with its associated metric to rank constituents by tracing uncertainties and errors in coupled model predictions back to uncertainties and errors in constituent model predictions.

The proposed approach evaluates the deficiency (relative degree of imprecision and inaccuracy), importance (relative sensitivity) and cost of further code development for each constituent model, and combines these three factors in a quantitative prioritization metric. The benefits of the proposed metric are demonstrated on a structural portal frame using an optimization-based uncertainty inference and coupling approach.

This study proposes an approach and its corresponding metric to prioritize the improvement of constituents by quantifying the uncertainties, bias contributions, sensitivity analysis, and cost of the constituent models.

For the proposed coupling transformer, a magnetic bypass based on the virtual air gap principle is realized by inserting auxiliary windings in a return leg added to a standard transformer. With such a setup, it is able to act as a voltage regulator as well as protect the power electronics of the dynamic voltage restorer from electrical grid fault currents. This paper focuses on the electrical design part of the coupling transformer. It aims to explain how the behavior of the auxiliary windings electrical circuit of the magnetic bypass impacts the performances of the device.

The influence of the electrical auxiliary windings circuit configurations on the operation of the coupling transformer is studied by finite element analyses with nonlinear and isotropic magnetic materials.

A configuration for the realization of the electrical circuit of the auxiliary windings is determined according to the finite element simulation results to achieve the design of the coupling transformer whose magnetic core was previously designed.

By studying the operation of a special coupling transformer with nonlinear saturation phenomenon by finite element analyses, a to-do list of the electrical circuit parameters is described to design this device well.

This study aims to investigate the effect of gusts on aircraft wake vortices. Aircraft wake vortices present a potential risk to following aircraft, particularly during final approach and landing, as wake vortices may remain in the flight corridor for a long time. Wind and turbulence are key factors that influence the wake vortex evolution and the wake vortex generation in the aircraft. Flying through a gust influences the wake vortex roll-up process and its evolution. Note that vertical and lateral gusts may affect counter-rotating wake vortices differently. Both vortices influence each other by inducing a downward velocity. Disturbances may therefore lead to local vortex tilting and later to a complex three-dimensional deformation. This work uses two different hybrid Reynolds-averaged Navier–Stokes/large-eddy simulation (RANS-LES) approaches to investigate the effect of gusts on wake vortex evolution. In a one-way coupling, a pre-calculated RANS velocity field of the aircraft’s near-field is being swept through an LES domain. The effect of a sine gust on the turbulent wake is modeled by manipulating the RANS-field accordingly. As a more sophisticated approach, the concept of a two-way coupling is being presented. Here an LES solver is bi-directionally coupled with an unsteady RANS (URANS) solver, exchanging values at every physical time step of the simulation.

A one-way coupling approach of the LES code MGLET and the RANS code TAU is presented to simulate the gust effect on aircraft wake vortices. Additionally, the concept of the two-way coupling of these two codes incorporating a coupling module.

The gust effect of wake vortices subjected to a crosswind can be simulated. The vortex physics is analyzed. Unexpected behavior like fast upwind vortex decay is revealed.

The understanding of the aircraft wake vortex physics during landing provides valuable information for wake vortex advisory systems.

The effect of gust on wake vortices during and after landing has not been studied so far. The hybrid one-way coupling approach, as well as the concept of the two-way coupling, are relatively new.

This paper aims to analyze the frequency characteristics of wireless power transfer (WPT) systems with relay resonators in terms of the power delivered to the load and system efficiency. Based on the analytical results, system parameters can be optimized to achieve maximum power transfer and higher system efficiency.

Based on Kirchhoff’s voltage law equations, WPT systems with relay resonators are described by the coupled linear second-order differential equations. Splitting frequencies are estimated by using the matrix theory. In addition, critical coupling conditions are demonstrated based on discriminant analysis.

It was found that multi-maximum values exist for the power delivered to the load and total system efficiency owing to multiple eigenfrequencies of the system. Also, frequency conditions of maximum power transfer and system efficiency, as well as their critical coupling conditions, were quantitatively estimated.

During our analytical process, we assume that quality factors of resonators in the system are high and the crossing coupling between resonators is negligible.

In previous works, the exact analysis of frequency characteristics is limited to WPT systems with two resonators. The appealing feature of this work lies in its ability to present a simplified analytical method with negligible approximation errors for WPT systems with relay resonators.

The purpose of this paper is to explore the relationship between effective knowledge management and corporate performance, to explore the dynamic symbiosis phenomenon of effective knowledge management based on organizational ecology with multinational companies (MNCs) and non-multinational companies (non-MNCs) and to explore the symbiosis strategy of knowledge management between multinational and non-multinational companies (non-MNCs) in China.

To measure effective knowledge management, this paper first uses structural equation model to measure knowledge management, based on the evolution dynamics equation in organizational ecology to measure the effectiveness of knowledge management, and studies the symbiosis of effective knowledge management between MNCs and non-MNCs based on ecological perspective.

Effective knowledge management can promote the financial performance of enterprises, but different degrees of effectiveness have different effects. In addition, the coupling and collaboration between knowledge management and corporate performance can reflect the value of effective knowledge management. The results show that effective knowledge management plays a positive moderating effect between knowledge management and corporate performance. Finally, the effective knowledge management system of MNCs (non-MNCs) has negative effect on non-MNCs (MNCs), showing the exclusive relationship between MNCs and non-MNCs in China.

The effectiveness of knowledge management is only based on the measurement of financial performance coupling. For other types of performance, it needs to be tested. The samples may not cover symbiosis relationship of effective knowledge management in other countries.

This paper provides practical and theoretical reference for confirming the symbiotic interaction and identifying the opportunities and challenges of knowledge management among different types of corporation groups.

The paper is one of the pioneering studies to explore the pattern of symbiotic evolution of effective knowledge management between MNCs and non-MNCs. From completely new perspectives, this study advances the research of knowledge management to a new and promising area.

This paper aims to present a fluid-structure coupling partitioned scheme involving rigid bodies supported by spring-damper systems. This scheme can be used with already existing fluid flow solvers without the need to modify them.

The scheme is based on a modified Broyden method. It solves the equations of solid body motion in which the external forces coming from the flow are provided by a segregated flow solver used as a black box. The whole scheme is implicit.

The proposed partitioned method is stable even in the ultimate case of very strong fluid–solid interactions involving a massless cylinder oscillating with no structural damping. The overhead associated with the coupling scheme represents an execution time increase by a factor of about 2 to 5, depending on the context. The scheme also has the advantage of being able to incorporate turbulence modeling directly through the flow solver. It has been tested successfully with URANS simulations without wall law, thus involving thin high aspect-ratio cells near the wall.

Such problems are known to be very difficult to solve and previous studies usually rely on monolithic approaches. To the authors' knowledge, this is the first time a partitioned scheme is used to solve fluid–solid interactions involving massless components.