Advanced System Simulation Research Articles

Development of Organs-on-Chips and Their Impact on Precision Medicine and Advanced System Simulation.

Drugs may undergo costly preclinical studies but still fail to demonstrate their efficacy in clinical trials, which makes it challenging to discover new drugs. Both in vitro and in vivo models are essential for disease research and therapeutic development. However, these models cannot simulate the physiological and pathological environment in the human body, resulting in limited drug detection and inaccurate disease modelling, failing to provide valid guidance for clinical application. Organs-on-chips (OCs) are devices that serve as a micro-physiological system or a tissue-on-a-chip; they provide accurate insights into certain functions and the pathophysiology of organs to precisely predict the safety and efficiency of drugs in the body. OCs are faster, more economical, and more precise. Thus, they are projected to become a crucial addition to, and a long-term replacement for, traditional preclinical cell cultures, animal studies, and even human clinical trials. This paper first outlines the nature of OCs and their significance, and then details their manufacturing-related materials and methodology. It also discusses applications of OCs in drug screening and disease modelling and treatment, and presents the future perspective of OCs.

Experimental investigation on a vertical sectorization system with active antenna

Cell splitting is an effective way of implementing network densification in order to boost the capacity of a mobile system. Traditionally, the cell splitting procedure has been carried out in the azimuth dimension. However, another approach known as vertical sectorization has been gaining momentum recently, where the sectors of a conventional cellular system are split vertically instead, creating inner and outer cells by using AAS technology. Then vertical sectorization can use the same communication resources in both inner and outer parts of the cells. Performance of vertical sectorization has been extensively studied in the literature using advanced system simulations. However, field measurements to characterize the actual performance of vertical sectorization with AAS have been scarce so far. In this article, we first identify key issues that may hinder the smooth implementation of commercial cellular systems using vertical sectorization. Then we present the results of a measurement campaign that was carried out to study these limitations and to identify the actual vertical radiation patterns when AAS technology is used. Finally, we reflect on some problems that remain open to make future cellular systems using vertical sectorization with AAS commercially viable.

An advanced simulation platform to support combustion developments in DISI engines: From engine design to control and calibration

Severe emission standards and competition with Diesel-engines encourage the development of innovating Spark-Ignition (SI) engines. However, innovating technologies lead to new challenges and mastering such engine systems requires long, extensive and costly test periods.In this context numerical simulations may strongly assist engine-designers over all stages of power-train development, from engine design, over calibration to engine control.IFP Energies nouvelles (IFPEN) has a large experience in the development of engine simulation platforms. In particular models describing the complex physical phenomena inside IC-engine combustion chambers have strongly improved. For SI engines a 0-dimensional Coherent Flame Model (CFM1D) has been developed and improved continuously. The model relies principally on physical equations for turbulence and combustion processes. Current versions account for the impact of various fuels on SI combustion and are able to predict engine emissions such as HC, CO/CO2 or NOx. Abnormal combustions such as engine knock are modelled as well.The aim of this communication is to illustrate the great potential of advanced system simulations for the automotive industry and to present the capacities of CFM1D. The communication presents model applications and gives an overview of model potentials for Engine Control: Real-time simulation for control purposes of a 4-cylinder turbocharged engine; Engine pre-mapping of innovative power-train concepts: Virtual calibration of a downsized DI engines and evaluation on NEDC and real cycles.

60‐GHz MHMIC six‐port model analysis

AbstractNew passive millimeter wave circuits built on thin alumina substrate are presented. A six‐port model is generated using measurement results of a 90° hybrid coupler. Good correlations between model and circuit measurements are proven. The proposed model is suitable for advanced system simulations of V‐band wireless personal area networks. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 2104–2108, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25377