Interconnection and damping assignment passivity-based non-linear observer control for efficiency maximization of permanent magnet synchronous motor

The permanent magnet synchronous motor (PMSM) has several advantages over the DC motor and is gradually replacing it in the industry. The dynamics of the PMSM are described by non-linear equations; it is sensitive to unknown external disturbances (load), and its characteristics vary over time. All of these restrictions complicate the control task. Non-linear controls are required to adjust for non-linearities and the drawbacks mentioned above. This paper investigates an interconnection and damping assignment (IDA) passivity-based control (PBC) combined with a non-linear observer approach for the PMSM using the model represented in the dq-frame. The IDA-PBC approach has the inherent benefit of not canceling non-linear features but compensating them in a damped manner. The suggested PBC is in charge of creating the intended dynamic of the system, while the non-linear observer is in charge of reconstructing the recorded signals in order to compel the PMSM to track speed. The primary objective of this study is to synthesize the controller while accounting for the whole dynamic of the PMSM and making the system passive. It is performed by restructuring the energy of the proposed strategy and introducing a damping component that addresses the non-linear elements in a damped instead of deleted way, so providing a duality concept between both the IDA-PBC and the observer There are three methods for computing IDA-PBC: parametric, nonparametric, and algebraic. The parameterized IDA-PBC method is used to control the speed of the PMSM. This method uses the energy function in parameterized closed-loop in terms of some functions depending on the system’s state vector, such that the energy formation step is satisfied. Then, the original port-controlled Hamiltonian (PCH) dynamics in open-loop (OL) are equalized with the desired one in closed-loop (CL). The equalization process allows obtaining a set of solutions of the partial differential equations. The latter must be solved in terms of the parameters of the energy function of the closed-loop. Finally, the stability properties are studied using the Lyapunov theory. Generally, the proposed candidate offers high robustness, fast speed convergence, and high efficiency over the conventional benchmark strategies. The effectiveness of the proposed strategy is performed under extensive numerical investigation with MATLAB/Simulink software

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Nouvelle architecture de DDS haute fréquence basse consommation compatible CMOS basée sur un incrément de phase variable

National audienceAprès un bref rappel des architectures conventionnelles de synthétiseurs digitaux directs (DDS) et des différents compromis qu'elles imposent en termes de consommation, de montée en fréquence, de diversité des formes d'ondes et de technologie utilisée, nous présentons une nouvelle architecture de DDS capable de réconcilier ces différentes contraintes, basée sur un générateur d'incréments de phase variables. Cet article présente le principe, les simulations comportementales ainsi que les résultats obtenus sur une technologie CMOS 65 nm

Nouvelle architecture de DDS haute fréquence basse consommation compatible CMOS basée sur un incrément de phase variable

National audienceAprès un bref rappel des architectures conventionnelles de synthétiseurs digitaux directs (DDS) et des différents compromis qu'elles imposent en termes de consommation, de montée en fréquence, de diversité des formes d'ondes et de technologie utilisée, nous présentons une nouvelle architecture de DDS capable de réconcilier ces différentes contraintes, basée sur un générateur d'incréments de phase variables. Cet article présente le principe, les simulations comportementales ainsi que les résultats obtenus sur une technologie CMOS 65 nm

Inter-Domain Mobility Management Solution for Service Continuity in IMS-based Networks

International audienceNowadays, wireless networks with heterogeneous technologies are largely deployed and, mobile terminals have multiple interfaces to access these networks. This raises many research issues such as the simultaneous access to heterogeneous networks and the mobility management. This paper proposes to manage the mobility of a terminal in this context. In particular, we want to guarantee that, while a terminal is moving from a given network to a different one, the quality of service of its applications will be maintained. For this purpose, we combine a multi-homing protocol (SHIM6) with an IMS architecture. The protocol SHIM6 ensures a seamless change of networks without any application disruption. The IMS architecture allows the establishment of multimedia session with quality of service. Our solution can manage the inter-domain mobility of a terminal in a reactive and proactive mode. For this purpose, we implement a SIP proxy inside the mobile terminal. The experimental evaluation shows the feasibility of the SHIM6-IMS integration and a considerable reduction of the handover delay

A SIP-SHIM6 Based Solution for Seamless Intra-Domain Mobility in IMS Networks

International audienceThe context of our work is mobile multi-homed terminals in a heterogeneous environment. We propose a solution for seamless terminal mobility in an intra-domain context. We combine a multi-homing protocol (SHIM6), which ensures seamless network change, with the IMS architecture, which allows the establishment of multimedia session with Quality of Service. Our proposal allows a mobile terminal to change its access network seamlessly, without any application disruption. To achieve this, we implement a Proxy-SIP inside the terminal to manage session establishment. The proposed scheme can manage access network change in two modes: reactive and proactive. A testbed allowed us to show the feasibility of our approach and the gain obtained by considerably reducing the handover delay and, thus, data loss

A SIP-SHIM6-Based Solution Providing Interdomain Service Continuity in IMS-based Networks

International audienceNowadays, wireless networks are largely deployed, and the number of smart phones has boomed, as well as data transfer via mobile phones. This has resulted in the emergence of multihoming, which allows the user to enjoy the best access for each application. The context of our work is mobile multihomed terminals in a heterogeneous environment. We propose a solution for interdomain mobility management with end-to-end service continuity of communication. For this purpose, we combine a multihoming protocol (SHIM6), which ensures a seamless network change, with the IMS architecture, which allows the establishment of multimedia sessions with quality of service. Our proposal enables a mobile terminal to change its access network seamlessly, without any application disruption. To achieve this, we implement a P-SIP inside the terminal to manage the signaling procedures. The proposed scheme can manage the interdomain mobility of a terminal in two modes: reactive and proactive. A testbed allows us to show the feasibility of our approach and the obtained gain by reducing considerably the handover delay and thus, the data loss

Hydrogen doped BaTiO3 films as solid-state electrolyte for micro-supercapacitor applications

International audienceSolid electrolytes are important part of all-solid state energy systems that store electrical energy on the chip. They allow a direct incorporation of micro-storage component with simple device architecture while operating at higher temperatures compared to liquid electrolytes. However, solid electrolytes are usually deposited at high temperatures, exceeding the thermal budget of current semiconductor technology. Herein, we report on the synthesis of high performance BaTiO3:H films as solid state electrolyte in which we incorporate protons during a room temperature RF sputtering process. Drastic changes occur on chemical, structural and electrical properties of the films when they accommodate highly mobile and reactive protons. BaTiO3:H films have well-defined crystalline phases and display an optical bandgap which decreases by increasing the HMR in the sputtering gas. In addition, these films show two relaxation processes. The first, thermally activated with an energy around 0.5 eV, emerges at low temperature due to the proton diffusion within the oxide material. The diffusion of positively charged oxygen vacancies by overcoming an energetic barrier of about 1.1 eV yields to a second relaxation which takes place at relatively high temperature. By using carbon nanowalls as high effective area bottom electrode, we anticipate a large specific capacitance