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This paper aims to present the model and method involving multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of elastohydrodynamic lubrication (EHL), according to the cam wear prediction using Archard’s model. Cam–follower kinematic pairs always work under wear because of concentrated contacts. Given that a cam and follower contact often operates in the mixed or boundary lubrication regime, simulation of cam wear is a multidisciplinary problem including kinematic considerations, dynamic load and stress calculations and elastohydrodynamic film thickness evaluations.

Multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of EHL are applied to obtain the dynamic loads, the time histories of contact pressure and the oil film thicknesses in cam–follower conjunctions to predict cam wear quantitatively.

The wear depth of the cam in the valve train of a heavy-load diesel engine is calculated, which is in good agreement with the measured value in the practical test. The results show that the cam–tappet pair operates under a mixed lubrication or boundary lubrication, and the wear depths on both sides of the cam nose are extremely great. The wear of these points can be decreased significantly by modifying the local cam profile to enlarge the radii of curvature.

The main value of this work lies in the model and method involving multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of EHL, which can give good prediction for the wear of cam.

The purpose of this paper is to model the aircraft-cargo’s coupling dynamics during ultra-low altitude heavy cargo airdrop and to design the aircraft’s robust flight control law counteracting its aerodynamic coefficients perturbation induced by ground effect and the disturbance from the sliding cargo inside.

Aircraft-cargo system coupling dynamics model in vertical plane is derived using the Kane method. Trimmed point is calculated when the cargo fixed in the cabin and then the approximate linearized motion equation of the aircraft upon it is derived. The robust stability and robust H_∞ optimal disturbance restraint flight control law are designed countering the aircraft’s aerodynamic coefficients perturbation and the disturbance moment, respectively.

Numerical simulation shows the effectiveness of the proposed control law with elevator deflection as a unique control input.

The model derived and control law designed in the paper can be applied to heavy cargo airdrop integrated design and relevant parameters choice.

The dynamics model derived is closed, namely, the model can be called in numerical simulation free of assuming the values of parachute’s extraction force or cargo’s relative sliding acceleration or velocity as seen in many literatures. The modeling is simplified using Kane method rather than Newton’s laws. The robust control law proposed is effective in guaranteeing the aircraft’s flight stability and disturbance restraint performance in the presence of aerodynamic coefficients perturbation.

The purpose of this paper is to study the influence of friction on static and dynamic characteristics, as well as the strength and lifetime of a flexible three-axes computer numerical control (CNC) machine tool.

The machine tool is first modeled by using finite element method to analyze static structure with frictionless surface-to-surface contact type. Because the machine tool structure is becoming more and more sophisticated over time, the significant influence of contact conditions between structural elements on the dynamic characteristics of the whole structure must be considered. To examine the dynamic effects caused by inertia forces and displacement of moving bodies on contact stress, the coefficient of friction between two contact bodies is added to perform dynamic simulation and compare the results with the static analysis results.

Distribution of stress and contact forces in solid-flexible contact is also studied by using the fundamental dynamic characteristics of a bushing joint.

Finally, the influence of dynamic structure, cutting conditions and material properties on the strength and lifetime of the CNC machine tool is discussed by using fatigue analysis. Consequently, this research can be used for efficient simulation of structural dynamics, lifetime assessment and interactions of the real CNC machine with the machine tool structure in a virtual environment.

The purpose of this paper is to provide a method with convenient modelling as well as precise computation to the research of complex multi-body system, such as robot arms and solar power satellite. Classical modelling method does not always fit these two requirements.

In this paper, tensor coordinates (TC) and homogeneous tensor coordinates (HTC) method with gradient components are developed, which also have a convenient interface with classical theory.

The HTC proved its precision and effectiveness by two examples. In HTC model, equations have a more convenient form as matrix and the results coincide well with classical one.

There is no plenty detailed operations supported in mathematics yet, which may be developed in further research.

With TC/HTC method, the research work can be separated more thoroughly: a simpler modelling work is left to scientists, when more computing work is handed to the computers. It may ease scientists’ brains in multibody modelling.

The HTC method has the advantages of absolute nodal coordinate formulations, tensor and homogeneous coordinate (HC) and it may be used in multibody mechanics, or other related engineerings.

In this paper, a novel and unified method for geometry configuration simulation of flexible cable under certain boundary conditions is presented. This methodology can be used to realize cable assembly verification in any computer-aided design/manufacturing system. The modeling method, solution algorithm, geometry configuration simulation and experimental results are presented to prove the feasibility of this proposed methodology. The paper aims to discuss these issues.

Considering the gravity, bending and torsion, modeling of cable follows the Kirchhoff theory. For this purpose, Euler quaternions are used to describe its spatial geometry configuration by a carefully chosen set of coordinates. Then the cable is discretized by the FEM, and the equilibrium condition per element is computed. In this way, the global static behavior is independent of the discretization. The static evolution of the cable is obtained by numerical integration of the resulting Kirchhoff equations. Then the manner is demonstrated, in which this system of equations can be decoupled and efficiently solved. Geometry configuration simulation examples with different boundary conditions are presented. Finally, experiment validation are given to describe the effectiveness of the models and algorithms.

The method presented in this paper can be adapted to computer-aided assembly verification of flexible cable. The experimental results indicate that both of the model and algorithm are efficient and accurate.

The method should be extended to flexible cables with multiple branches and more complex constraints (holes, curved surfaces and clamps) and non-circular sections. Dynamic assembly process simulation based on the Kirchhoff theory must be considered in the future.

Unlike in previous approaches, the cable behavior was independent of the underlying discretization, and the finite element approach enables physically plausible cable assembly verification.

The purpose of this paper is to propose an efficient iterative method for large-scale finite element equations of bad numerical stability arising from deformation analysis with multi-point constraint using Lagrange multiplier method.

In this paper, taking warpage analysis of polymer injection molding based on surface model as an example, the performance of several popular Krylov subspace methods, including conjugate gradient, BiCGSTAB and generalized minimal residual (GMRES), with diffident Incomplete LU (ILU)-type preconditions is investigated and compared. For controlling memory usage, GMRES(m) is also considered. And the ordering technique, commonly used in the direct method, is introduced into the presented iterative method to improve the preconditioner.

It is found that the proposed preconditioned GMRES method is robust and effective for solving problems considered in this paper, and approximate minimum degree (AMD) ordering is most beneficial for the reduction of fill-ins in the ILU preconditioner and acceleration of the convergence, especially for relatively accurate ILU-type preconditioning. And because of concerns about memory usage, GMRES(m) is a good choice if necessary.

In this paper, for overcoming difficulties of bad numerical stability resulting from Lagrange multiplier method, together with increasing scale of problems in engineering applications and limited hardware conditions of computer, a stable and efficient preconditioned iterative method is proposed for practical purpose. Before the preconditioning, AMD reordering, commonly used in the direct method, is introduced to improve the preconditioner. The numerical experiments show the good performance of the proposed iterative method for practical cases, which is implemented in in-house and commercial codes on PC.

This study aims to explore the complex, multi-level institutional dynamics of smart city reforms and projects and their potential sustainability pressures on the implementation of a management accounting system in an Egyptian state-owned enterprise (SOE), which has a politically sensitive institutional character.

This study adds to institutional management accounting research using a multi-level perspective of institutional dynamics in the smart city context. Data were collected from an interpretive case study of an Egyptian SOE that was under socio-political sustainability pressures to implement a smart electricity network project in New Minya city.

Smart city projects have formed social and political sustainability pressures, which introduced the enterprise resource planning (ERP) network as a new management accounting system. A new (complex and multi-level) management accounting system was invented to reinvent the sustainable city as an “accounting city” (which appeared rhetorically as a “smart city”). “Smart” being the visibility and measurability of the sustainability performance of the collective body, which calls the city and its connectivity to different institutional levels brought out in a city network project for the ERP-enabled electricity distribution.

This study examines a single case study from a single smart city and identifies the accounting community’s need for multiple and comparative case studies to further analyse the potential impact of smart city reforms and projects on the sustainable implementation of management accounting systems.

City policymakers and managers may benefit from the practical findings of this interpretive field-based case study in planning, implementing and monitoring smart city projects and objectives.

Individual and collective well-being may be enhanced through new management accounting forms of multi-level local governance and increased political, field and organisational sustainability.

This study provides important insights into the sustainability dynamics of management accounting in achieving smart city reforms. The achievement of sustainability management accounting systems has connected to multiple ERP roles at different institutional levels, which resulted in accommodating the socio-political objectives of smart city projects.

This paper presents algorithms for computing the angular velocities of the bodies of a multibody system. A multibody system is any collection of connected bodies. The focus is upon multibody systems consisting of spherically pinned rigid bodies which do not form closed loops. Simple formulae are presented for computing the angular velocities. It is shown that once the angular velocities are known the entire kinematical description and hence, the dynamics of the system, may be developed routinely and in automated fashion. Extension to more general multibody systems follows without conceptual change in the procedures.

Many European-level networks and regulatory constellations in different sectors (e.g., energy, telecommunications) without clear anchorage into the European Union (EU) institutional landscape have been subject to increasing efforts by the EU institutions to tie them closer to the EU. They are serving increasingly as platforms for preparing EU policy or for implementing EU decisions, which may result in closer institutional bonds with the EU. This chapter aims at examining the differences and similarities between the process towards more EU-integration in two different domains (i.e., telecommunications and patents) and regulatory constellations (i.e., supranational and intergovernmental).

The chapter analyzes the evolution in the European telecommunication sector and the European Patent System and juxtaposes this analysis with the literature on institutionalization, Europeanization of regulatory network-organizations, and multilevel governance (MLG). It focuses on the role of the European Commission and the interaction with the national regulatory agencies (NRAs) and networks within the institutional framework.

Irrespective of the particular regime (intergovernmental/supranational) in a certain domain or sector, a common trend of closer coordination and integration prompted by the Commission is taking place, which triggers a certain resistance by the national bodies regulating that domain. As long as a specific competence is considered instrumental in the creation of the single market, the Commission has strong incentives to strengthen its influence in this field, even if those competences have been regulated through an independent intergovernmental regime.

The dynamic described in this chapter allows us to reflect upon the MLG conception as developed by Marks and Hooghe (2004), which distinguish between two types of MLG. Type I MLG refers to different levels of governments, more specifically to the spread of power along different governmental levels and the interactions between them. Type II MLG refers to jurisdictions that are both task-specific and based on membership that can intersect with each other. They respond to particular problems in specific policy fields (Marks & Hooghe, 2004). Our analysis shows that the increase in coordination and integration are the outcome of both MLG Type II processes (coordination between two issue-specific bodies) and of MLG Type I processes (tensions between two governmental levels). Furthermore, the negotiation dynamics regarding this increased coordination and integration reveal that the tensions typical of MLG Type I took place as a consequence of the increased coordination between Type II bodies. Put differently, multi-level coordination and integration mechanisms in the EU can be seen as both Type I and Type II processes. They combine features of both categories and reveal that their Type I and Type II features are interdependent.

The analysis in this chapter shows a need for further strengthening the MLG Type I and II conceptual framework by balancing the analytical distinction between the two types with developments about how Type I and Type II are often entangled and intertwined with each other rather than separated realities.

The chapter describes and compares the dynamics in the European telecommunications sector and the European patent system with interesting observations for NRAs and the European Commission with respect to coordination and integration.

The original nature of the current chapter relates to the two selected areas and the addition to the literature on MLG.

First, with respect to the areas investigated the dynamics of the European telecommunications sector have been analyzed also by other authors, but the European patent system is an area which is relatively unexplored in terms of governance research. The combination of the two sectors with a detailed analysis of similarities and differences is highly original and generates interesting lessons with respect to coordination and integration in supranational and intergovernmental regimes.

Second, Marks and Hooghe (2004) distinguish between the two types of MLG as if they are two different constructs that are not related to each other. Our cases and argument cover both types of MLG and show the interconnection between the dynamics taking place in the two types of MLG.