Design of Aerodynamic Ball Levitation Laboratory Plant

This paper presents the development of a new Aerodynamic Ball Levitation Laboratory Plant at the Center of Modern Control Techniques and Industrial Informatics (CMCT&II). The entire design process of the plant is described, including the component selection process, the physical construction of the plant, the design of a printed circuit board (PCB) powered by a microcontroller, and the implementation of its firmware. A parametric mathematical model of the laboratory plant is created, whose parameters are then estimated using a nonlinear least-squares method based on acquired experimental data. The Kalman filter and the optimal state-space feedback control are designed based on the obtained mathematical model. The designed controller is then validated using the physical plant.

A sampling-based approach for handling delays in continuous and hybrid systems

Delays in feedback dynamics of coupled dynamical systems arise regularly, especially in embedded control where the physical plant and the controller continuously interact through digital networks. Systems featuring delays are however notoriously difficult to analyze. Consequently, formal analysis often addresses simplified, delay-free substitute models, risking negligence of the adverse impact of delay on control performance. In this ongoing work, we demonstrate that for continuous systems such as delay differential equations, a major part of the delay-induced complexity can be reduced effectively when adding natural constraints to the model of the delayed feedback channel, namely that it transports a band-limited signal and implements a non-punctual, distributed delay. The reduction is based on a sampling approach which is applicable when the above conditions on the feedback are satisfied. We further discuss the possibilities of lifting this method to mixed discrete-continuous dynamics of delayed hybrid systems and the open issues thereof.

Supporting the pursuit of professionalism during a crisis

BackgroundCrisis plans for healthcare organisations most often focus on operational needs including staffing, supplies and physical plant needs. Less attention is focused on how leaders can support and encourage individual clinical team members to conduct themselves as professionals during a crisis.MethodsThis qualitative study analysed observations from 79 leaders at 160 hospitals that participate in two national professionalism programmes who shared their observations in focus group discussions about what they believed were the essential elements of leading and addressing professional accountability during a crisis.ResultsAnalysis of focus group responses identified six leadership practices adopted by healthcare organisations, which were felt to be essential for organisations to navigate the crisis successfully. Unique aspects of maintaining professionalism during each phase of the pandemic were identified and described.ConclusionsLeaders need a plan to support an organiation’s pursuit of professionalism during a crisis. Leaders participating in this study identified practices that should be carefully woven into efforts to support the ongoing safety and quality of the care delivered by healthcare organisations before, during and after a crisis. The lessons learnt from the COVID-19 pandemic may be useful during subsequent crises and challenges that a healthcare organisation might experience.

The French Hong: The Physical Plant

Chapter 5 focuses on the buildings that provided the French with living, work, and warehouse space in Canton; over the years, they rented at least seven different ones, and occasionally more than one at a time. They most often referred to these structures, which were a familiar form of Cantonese vernacular architecture, as hangs or hams (hongs), and only rarely as factoreries (factories). Their 1767 renovations to the façade of the hong that they rented from the merchant Tinqua were widely emulated by other trading nations on the Canton riverfront; less impressively, control of the same hong was twice a cause of major friction among French traders, the second time with long-lasting consequences. Besides identifying the various French hongs and locations, building structure, layout, furnishings, and residents, the chapter also explores the significance of the hong, to both the Chinese and the international community, as the symbol of a nation’s success in the Canton Trade. As the outward expression of a nation’s presence in Canton, the hong served as the public face of that nation, and thus came to assume an importance that far exceeded any merely physical function.

The Shanghai Mint and Establishing a Silver Standard in China, 1920–1933

This chapter uses the story of the Shanghai Mint as a lens to examine the financial history of China in the 1920s and early 1930s to show how familiar events occurred in economic history. It reviews political and economic changes within China that influenced monetary reform on the last silver frontier. It also talks about the construction of the mint, which started in 1921 and produced coins in the spring of 1933. The chapter refers to China's movement from the warlord period of the late 1910s and early 1920s to the Nationalist period wherein the new government inherited the goals of currency reform from its predecessors and the half-finished physical plant of the Shanghai Mint. It looks at the history of the mint that connects small technical details to much larger political and economic issues, such as the types of coining equipment to be used and the design of coins.

H∞ CONTROL DESIGN OF A MULTITANK SYSTEM

This paper considers MATLAB® modeling and simulation of H∞ controller and its realization on the Multitank System. The first task is to study the physical plant of the laboratory Multitank System and to apply a given mathematical model for optimal controller design. The general objective of the derived regulator is to reach and stabilize the level in the tanks by an adjustment of the pump operation or/and valves settings. Finally, it is necessary to simulate the obtained closed-loop system and to test its workability.