Top-level modeling theory of multi-discipline virtual prototype

Multi-disciplinary virtual prototypes of complex products are increasingly and widely used in modern advanced manufactur- ing. How to effectively address the problems of unified modeling, composition and reuse based on the multi-disciplinary heteroge- neous models has brought great challenges to the modeling and simulation （M＆S） science and technology. This paper presents a top-level modeling theory based on the meta modeling framework （M2F） of the COllaborative SIMulation （COSlM） theory of virtual prototyping to solve the problems. Firstly the fundamental prin- ciples of the top-level modeling theory are decribed to expound the premise, assumptions, basic conventions and special require- ments in the description of complex heterogeneous systems. Next the formalized definitions for each factor in top level modeling are proposed and the hierarchical nature of them is illustrated. After demonstrating that they are self-closing, this paper divides the top- level modeling into two views, static structural graph and dynamic behavioral graph. Finally, a case study is discussed to demon- strate the feasibility of the theory.

A Survey of Output Feedback Robust MPC for Linear Parameter Varying Systems

For constrained linear parameter varying(LPV)systems,this survey comprehensively reviews the literatures on output feedback robust model predictive control(OFRMPC)over the past two decades from the aspects on motivations,main contributions,and the related techniques.According to the types of state observer systems and scheduling parameters of LPV systems,different kinds of OFRMPC approaches are summarized and compared.The extensions of OFRMPC for LPV systems to other related uncertain systems are also investigated.The methods of dealing with system uncertainties and constraints in different kinds of OFRMPC optimizations are given.Key issues on OFRMPC optimizations for LPV systems are discussed.Furthermore,the future research directions on OFRMPC for LPV systems are suggested.

The effects of pressure, temperature, and depth/diameter ratio on the microvia filling performance of Ag-coated Cu micro-nanoparticles for advanced electronic packaging

Conductive fillers made from metal nanoparticles offer many advan-tages for the fabrication of a variety of electronic devices,but when they have a porous structure,their poor conductivity limits their adoption in many applications.In this study,an Ag-coated Cu micro-nanoparticle paste is used to achieve compact filling of blind vias on flexible copper clad polyimide laminates through a multistep filling and sintering tech-nique.The filled blind vias achieve a resistivity as low as 6.2μΩ·cm,which is comparable that of electroplated blind vias.Higher sintering pressure and temperature promote the filling performance,while the conductivity deteriorates at a via depth/diameter ratio greater than 1:1.Finite element simulations reveal a stress inhomogeneity in vias with large depth/diameter ratios,which is the key to understanding the evolution of the conductive properties of a paste-filled via.This study provides an effective method for high-performance microvia filling as well as insights into the mechanism that influences its performance.

CoSMSOL:Complex system modeling,simulation and optimization language

Complex System Modeling,Simulation and Optimization Language(CoSMSOL)is problem-oriented and designed to run on multi-core computers.This paper provides the system environment of CoSMSOL and proposes the modeling methods of complex system,language text specification,function library,algorithm library,parallel simulation algorithms and intelligent optimization algorithms which support continuous system,discrete system and agent systems.Also,we developed a simulation language compiler of CoSMSOL,which is employed in two case studies generating a multi-entity war gaming system and an aerodynamic spacecraft model.The two cases illustrate main functions and implementation processes of CoSMSOL.The results validate that CoSMSOL is useful to model agent-based system and aerospace system.