A GaAs MMIC chip-set for 10 to 15GHz radio-links applications

This paper describes the development of a GaAs MMIC chip-set for Ku-band radio-links transmitter. This chip-set includes two circuits, a times-two multiplier 5-7.5GHz to 10-15GHz, and a single side band up-converter. The development and the results of these circuits are analysed. The times-two multiplier is based on a specific balanced configuration leading to a very high level of input frequency suppression at the output (typically 50dBc) on a 2.7mm² chip. The mixer circuit is a broadband build-in single side band mixer of 10mm², with typically 30dBc image suppression

The ss-semantics approach; theory and applications

AbstractThis paper is a general overview of an approach to the semantics of logic programs whose aim is to find notions of models which really capture the operational semantics, and are, therefore, useful for defining program equivalences and for semantics-based program analysis. The approach leads to the introduction of extended interpretations which are more expressive than Herbrand interpretations. The semantics in terms of extended interpretations can be obtained as a result of both an operational (top-down) and a fixpoint (bottom-up) construction. It can also be characterized from the model-theoretic viewpoint, by defining a set of extended models which contains standard Herbrand models. We discuss the original construction modeling computed answer substitutions, its compositional version, and various semantics modeling more concrete observables. We then show how the approach can be applied to several extensions of positive logic programs. We finally consider some applications, mainly in the area of semantics-based program transformation and analysis

Diagnosis and treatment of acute pancreatitis: The position statement of the Italian Association for the study of the pancreas

BACKGROUND AND AIM: Till now, no Italian studies providing information on acute pancreatitis have been published. The aim of this study was to evaluate the epidemiological and clinical characteristics of acute pancreatitis in Italy. MATERIALS AND METHODS: The study involved 37 Italian centres distributed homogeneously throughout the entire national territory and prospectively collected epidemiological, anamnestic, laboratory, radiological, therapeutic (pharmacological, endoscopic and surgical) data, relevant to each individual case of acute pancreatitis consecutively observed during the period from September 1996 to June 2000. RESULTS: One thousand two hundred and six case report forms were collected, but 201 patients (16.6%) were subsequently eliminated from the final analysis. We therefore studied 1005 patients, 533 (53%) males and 472 (47%) females, mean age 59.6 +/- 20 years. On the basis of the Atlanta classification of acute pancreatitis, 753 patients of the 1005 cases analysed (75%) were mild and 252 patients (25%) severe. The aetiology was biliary in 60% of the patients, related to alcohol abuse in 8.5%, while in 21% of the cases it could not be identified. Over 80% of the patients (83%) were admitted to hospital within 24 h from the onset of clinical symptoms, while only 6% were admitted after 48 h. In particular, 65% of the patients were admitted to hospital within the first 12 h. Antibiotics were used in 85% of the severe and 75% of mild forms. Endoscopic therapy was carried out in 65% of the severe cases, but only in 40% it was carried out prior to 72 h. Eighty-five patients (8.5% of the total, 34% of the severe forms) underwent surgical intervention: 20% on the first day, 38.5% within the fourth day, and the remaining (41.5% of the cases) later on for infected necrosis. The mean duration of hospitalisation for patients with mild pancreatitis was 13 +/- 8 days, while for the severe disease it was of 30 +/- 14 days. The overall mortality rate was 5%, 17% in severe and 1.5% in mild pancreatitis. CONCLUSIONS: Acute pancreatitis in Italy is more commonly a mild disease with a biliary aetiology. The treatment of the disease is not optimal and, on the basis of these data, needs to be standardised. Despite this, the overall mortality rate is low (5%BACKGROUND AND AIM: Till now, no Italian studies providing information on acute pancreatitis have been published. The aim of this study was to evaluate the epidemiological and clinical characteristics of acute pancreatitis in Italy. MATERIALS AND METHODS: The study involved 37 Italian centres distributed homogeneously throughout the entire national territory and prospectively collected epidemiological, anamnestic, laboratory, radiological, therapeutic (pharmacological, endoscopic and surgical) data, relevant to each individual case of acute pancreatitis consecutively observed during the period from September 1996 to June 2000. RESULTS: One thousand two hundred and six case report forms were collected, but 201 patients (16.6%) were subsequently eliminated from the final analysis. We therefore studied 1005 patients, 533 (53%) males and 472 (47%) females, mean age 59.6 +/- 20 years. On the basis of the Atlanta classification of acute pancreatitis, 753 patients of the 10

Autonomous Vehicles Management in Agriculture with Bluetooth Low Energy (BLE) and Passive Radio Frequency Identification (RFID) for Obstacle Avoidance

Obstacle avoidance is a key aspect for any autonomous vehicles, and their usage in agriculture must overcome additional challenges such as handling interactions with agricultural workers and other tractors in order to avoid severe accidents. The simultaneous presence of autonomous vehicles and workers on foot definitely calls for safer designs, vehicle management systems and major developments in personal protective equipment (PPE). To cope with these present and future challenges, the “SMARTGRID” project described in this paper deploys an integrated wireless safety network infrastructure based on the integration of Bluetooth Low Energy (BLE) devices and passive radio frequency identification (RFID) tags designed to identify obstacles, workers, nearby vehicles and check if the right PPE is in use. With the aim of detecting workers at risk by scanning for passive RFID-integrated into PPE in danger areas, transmitting alerts to workers who wear them, tracking of near-misses and activating emergency stops, a deep analysis of the safety requirements of the obstacle detection system is shown in this study. Test programs have also been carried out on an experimental farm with detection ranging from 8 to 12 meters, proving that the system might represent a good solution for collision avoidance between autonomous vehicles and workers on foot