Analytical flux density determination in the SPM slotless machine stator core

Slotless machines equipped with surface permanent magnet (SPM) rotor are used in such applications where the torque ripple and the additional losses, due to the slotting effect, are critical issues. This kind of machine allows to find an accurate and analytical solution for the magnetic fields in every machine cross section domain. This paper derives an analytical expression for the magnetic field distribution inside the stator core of a SPM slotless machine during general load condition. The case of different rotor magnetization pattern is also considered. All the results are assessed with finite element analysis showing a very good accordance

A New Method for the Analytical Determination of the Complex Relative Permeance Function in Slotted Electrical Machines

The complex relative permeance function is a suitable tool to predict the air gap magnetic field in slotted stator electrical machines. In the literature, the complex permeance function is usually identified by means of numerical techniques based on complex techniques such as conformal mapping or subdomain method. In this paper, an alternative approach is proposed. This method is based on solving the magnetostatic Laplace equation over a portion of the slotted air gap by imposing appropriate boundary conditions in the slot opening region. Such boundary condition tries to represent the theoretical trend of the magnetic field divergence near the corner-shaped ferromagnetic regions. Furthermore, the Carter theory for the slot opening consideration is used. A fully analytical formulation for the complex relative permeance function is obtained, and its accuracy is assessed using finite element analysis

Simulations of the occurrence of runoff-generated debris flows by means of hydrological models in headwater rocky basins

The simulation of the occurrence of the runoff-generated debris flows can be approached by means of hydrological models. In this work, we show that a rainfall-runoff model designed for the simulation of runoff in headwater rocky basins can capture both the transit timing of the first debris-flow surge and its hydrograph. We successfully compared the stage hydrograph of debris flows with that of the simulated runoff in two headwater rocky basins of Dolomites

Design of two retention basins along the torrent Liera on the Gares Valley (Dolomites, North East Italy) after the storm Vaia

A storm called “Vaia” affected the North East Italy and South West of Austria at the end of October 2018. On the Gares Valley (Canale d’Agordo, North East Italian Alps), the abundant runoff triggered several in-channel debris flows that transported hundreds of thousands of cubic meters of sediments on the valley bottom. Some control works for retaining the sediment volume have then been built in the most threatened sites. Herein we show the design of two retention basins that should protect both the Liera torrent and the main road parallel to it. We computed the debris-flow volume to be retained both using an empirical law and simulated solid-liquid hydrographs corresponding to a return period of 300 years. The estimate of the debris-flow volume in the empirical law depends on the basin area upstream of the deposition zone, whereas, in the solid-liquid hydrographs, it depends on the area of the basin closed at the initiation area, as well as on the design rainfall

Rockfalls change the runout and frequency of debris flows at Punta Nera (Eastern Italian Alps)

In the Dolomitic region, many debris flow basins have headwaters characterized by extremely steep slopes of bare outcropping rock. Cliffs are commonly incised by multiple chutes which rapidly deliver runoff at their base where the channels incise scree deposits. Debris flows mobilize and transport sediment along such ephemeral channels following intense summer convective rainstorms. In the debris flow basin of Punta Nera, a series of rockfalls, which occurred in the upper part of the headwater between 2013 and 2016, caused dramatic changes in the debris flow dynamics. Starting from the summer of 2014, the runout of debris flow events increased so much that it reached the national road, which runs at the toe of the debris flow fan, attracting media attention and prompting the adoption of protective measures. Here, we use newspaper reports, direct observations, aerial and terrestrial photograph, monitoring data and topographic surveys to document the rockfalls and the debris flow activity. The sudden increase in sediment availability changed the magnitude of events, their runout and the critical conditions for debris-flow occurrence

Atypical Presentation of Acute Coronary Syndrome-Not ST Elevation: A Case Report

We describe the unexpected case of a 70-year-old man, with medical history of ischemic heart disease and surgery for aneurysm of abdominal aorta, who comes to the emergency department complaining of low-back pain without other symptoms or signs of organic failure. After a few hours we see a deterioration of physical conditions with pulmonary oedema, increase of blood pressure, changing in the ECG pattern, and worsening of left ventricular function with progressive increase of biomarkers for myocardial necrosis. So this pain has revealed the premature symptom of an acute coronary syndrome (ACS). After a short time a subsequent cardiac arrest complicates the clinical situation. After resuscitation, the patient undergoes successfully to coronary angiography and performed a percutaneous transluminal coronary angioplasty (PTCA)

A model-based early warning system for runoff-generated debris-flow occurrence: Preliminary results

Early warning systems for debris flows are low cost measures for mitigating this kind of hazard. The early warning systems provide a timely alert for upcoming events in order to take protective measures, such as closing railways-roads, evacuating people from the threatened areas, and put rescue forces into readiness. These systems usually are sensor-based, and the alert time is the interval between the timing of the first detachment of debris flow by a sensor and its arrival into the threatened area. At the purpose of increasing the alert time, we propose an early warning system based on a model-cascade: nowcasting, hydrological- and triggering models. Nowcasting anticipates rainfall pattern that is transformed into runoff by the hydrological model. The triggering model estimates the volume of sediments that the runoff can entrain, and compares it with a critical threshold. If this is exceeded the alert is launched. The proposed early warning system is tested against the available data of the Rovina di Cancia (Northeast Italy) site

Humans, resources, or what else?

The literature on human resource management shows growing attention to the “personal” dimension of the subject-organization relationship, while the subjectivist contributions do not disregard the discussion on managerial implications. This ebook proposes a reflection on this apparent convergence. It discusses the internal criticism arising from the mainstream literature and the criticism originating from different disciplinary perspectives (organization, sociology of science, psychology of work, and labor law). Alternatives to the idea of human resources are proposed through the reflection on the goals of the processes of actions and decisions, the ontological reflection on the idea of man, and the epistemological reflection on the choices that allow overcoming the objectivism/subjectivism antinomy

Beyond the Calhoun's dilemma

Le projet politique de l’Union européenne apparaît encagé dans le dilemme entre État fédéral ou Confédération d’États. Dans un cas, il s’agit de reconnaître une souveraineté, avec une Constitution et une représentation. Dans l’autre, il s’agit de conserver une pluralité de corps souverains unis par la formule du Traité. La recherche d’une synthèse entre ces deux perspectives semble niée à la racine. À y regarder de plus près, toutefois, ce dilemme subsiste à l’intérieur d’un horizon politique spécifique. Comme l’a récemment signalé Olivier Beaud, auteur de La Puissance de l’État (1994), le choix entre État fédéral et Confédération d’États présuppose le partage de la théorie moderne de la souveraineté. D’où l’exigence, avancée par le juriste français dans la Théorie de la Fédération (2007), d’ouvrir le débat politique sur l’Union européenne à une réflexion plus générale, ayant pour objectif la proposition d’un projet fédératif excédant l’alternative « état-centrique » entre État fédéral et Confédération d’États. Autrement dit, l’ambition de Beaud est de concevoir la Fédération comme ordre politique anti-souverain. Nous partageons cette initiative. D’autre part, nous proposons une conception fédérative différente de celle du juriste français. Cette distance théorique dépend, à son tour, d’une définition différente de la souveraineté moderne. Pour Beaud, cette dernière s’affirme avec Jean Bodin, théoricien de la monopolisation de la prérogative législative de la part de la puissance publique. Pour nous, en revanche, la souveraineté moderne est contresignée par cette logique qui, sur la base de l’accord volontaire de tous les individus impliqués, parvient à fonder un pouvoir absolu et représentatif de la totalité. De notre point de vue, il s’ensuit que la Fédération, entendue comme ordre politique alternatif à la Souveraineté, doit être pensée au-delà de ce mécanisme d’autorisation « démocratique » du pouvoir dont Thomas Hobbes est le père théorique.The political project of the European Union appears to be divided between the Federal state and the Confederation of states. On the one hand, it is fundamental to guarantee sovereignty through both a Constitution and by giving citizens representation. On the other, the goal is to preserve multiple sovereign institutions under the formula of a Treaty. Therefore, the attempt to combine these 2 perspectives turns out to be key. At a closer look, this dilemma can be identified within a specific political scenario. As recently mentioned by Olivier Beaud, author of the book La puissance de l’Etat (1994), the choice between the Federal State and the Confederation of States presupposes the sharing of the modern theory of sovereignty. Hence the need, highlighted by the French jurist in the Théorie de la Federation (2007), to open the political debate on the European Union to a more general reflexion which goal is the proposition of a federal project exceeding the alternative between Federal state and Confederation of States. In other words, Beaud’s plan consists of a Federation conceived as an anti-sovereign political organization. We approve this initiative. On the other hand, we suggest a different federal conception to the one of the French jurist. This difference is based on an alternative definition of the concept of modern sovereignty. In fact, according to Beaud, the concept of modern sovereignty is the one claimed by Jean Bodin, theorist of Les six Livres de la Republique. As far as we are concerned, modern sovereignty is based on the mutual agreement of all the individuals and forms an absolute power which is representative of everyone. In our view, the Federation seen as an alternative option to the Sovereignty has to be thought beyond the Thomas Hobbes’s concept of democratic authorisation