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Trunk flexion represents a risk factor for the onset of low-back disorders, yet limited quantitative data exist regarding flexion exposures in actual working conditions. In this study, we evaluated the potential of using a single inertial measurement unit (IMU) to classify trunk flexion, in terms of amplitude, frequency, and duration, and assessed the influence of alternative time durations on exposure results. Twelve warehouse workers were monitored during two hours of an actual shift while wearing a single IMU on their low back. Trunk flexion data were reduced using exposure variation analysis integrated with recommended exposure thresholds. Workers spent 5.1% of their working time with trunk flexion of 30–60° and 2.3% with flexion of 60–90°. Depending on the level of acceptable error, relatively shorter monitoring periods (up to 50 min) might be sufficient to characterize trunk flexion exposures. Future work is needed, however, to determine if these results generalize to other postural exposures and tasks.
Micaela Porta; Massimiliano Pau; Pier Francesco Orrù; Maury A. Nussbaum. Trunk Flexion Monitoring among Warehouse Workers Using a Single Inertial Sensor and the Influence of Different Sampling Durations. International Journal of Environmental Research and Public Health 2020, 17, 7117 .
AMA StyleMicaela Porta, Massimiliano Pau, Pier Francesco Orrù, Maury A. Nussbaum. Trunk Flexion Monitoring among Warehouse Workers Using a Single Inertial Sensor and the Influence of Different Sampling Durations. International Journal of Environmental Research and Public Health. 2020; 17 (19):7117.
Chicago/Turabian StyleMicaela Porta; Massimiliano Pau; Pier Francesco Orrù; Maury A. Nussbaum. 2020. "Trunk Flexion Monitoring among Warehouse Workers Using a Single Inertial Sensor and the Influence of Different Sampling Durations." International Journal of Environmental Research and Public Health 17, no. 19: 7117.
The demand for cost-effective, reliable and safe machinery operation requires accurate fault detection and classification to achieve an efficient maintenance strategy and increase performance. Furthermore, in strategic sectors such as the oil and gas industry, fault prediction plays a key role to extend component lifetime and reduce unplanned equipment thus preventing costly breakdowns and plant shutdowns. This paper presents the preliminary development of a simple and easy to implement machine learning (ML) model for early fault prediction of a centrifugal pump in the oil and gas industry. The data analysis is based on real-life historical data from process and equipment sensors mounted on the selected machinery. The raw sensor data, mainly from temperature, pressure and vibrations probes, are denoised, pre-processed and successively coded to train the model. To validate the learning capabilities of the ML model, two different algorithms—the Support Vector Machine (SVM) and the Multilayer Perceptron (MLP)—are implemented in KNIME platform. Based on these algorithms, potential faults are successfully recognized and classified ensuring good prediction accuracy. Indeed, results from this preliminary work show that the model allows us to properly detect the trends of system deviations from normal operation behavior and generate fault prediction alerts as a maintenance decision support system for operatives, aiming at avoiding possible incoming failures.
Pier Orrù; Andrea Zoccheddu; Lorenzo Sassu; Carmine Mattia; Riccardo Cozza; Simone Arena. Machine Learning Approach Using MLP and SVM Algorithms for the Fault Prediction of a Centrifugal Pump in the Oil and Gas Industry. Sustainability 2020, 12, 4776 .
AMA StylePier Orrù, Andrea Zoccheddu, Lorenzo Sassu, Carmine Mattia, Riccardo Cozza, Simone Arena. Machine Learning Approach Using MLP and SVM Algorithms for the Fault Prediction of a Centrifugal Pump in the Oil and Gas Industry. Sustainability. 2020; 12 (11):4776.
Chicago/Turabian StylePier Orrù; Andrea Zoccheddu; Lorenzo Sassu; Carmine Mattia; Riccardo Cozza; Simone Arena. 2020. "Machine Learning Approach Using MLP and SVM Algorithms for the Fault Prediction of a Centrifugal Pump in the Oil and Gas Industry." Sustainability 12, no. 11: 4776.
This paper describes the modelling and analysis of the processes and activities used in the Blood Transfusion Centre of Hospital Brotzu (Cagliari – Italy), via FMECA (Failure Modes Effects and Criticalities Analysis) method, in order to enhance patient safety and improve clinical risk management. The first part of the study consists on an analysis of the present blood transfusion chain processes (AS-IS), obtained by reverse engineering. Then a concise description of the FMECA methodology is presented. After the introduction of the reengineered process (TO-BE), developed via introduction of RFID technology, the results of simulation will be presented. For each activity of the two configurations studied (AS-IS and TO-BE) some performance indicators were evaluated, then a sensitivity analysis has been carried out to investigate the consistency of FMECA analysis. Finally follows the comparison of results between the simulation of actual process and the reengineered one.
Francesco Zedda; Gianluca Borelli; Francesco Valentino Caredda; Alessandro Fanti; Gianluca Gatto; Giuseppe Mazzarella; Pier Francesco Orrù; Andrea Volpi. FMECA Modelling and Analysis in Blood Transfusion Chain. International Journal of Privacy and Health Information Management 2017, 5, 23 -39.
AMA StyleFrancesco Zedda, Gianluca Borelli, Francesco Valentino Caredda, Alessandro Fanti, Gianluca Gatto, Giuseppe Mazzarella, Pier Francesco Orrù, Andrea Volpi. FMECA Modelling and Analysis in Blood Transfusion Chain. International Journal of Privacy and Health Information Management. 2017; 5 (1):23-39.
Chicago/Turabian StyleFrancesco Zedda; Gianluca Borelli; Francesco Valentino Caredda; Alessandro Fanti; Gianluca Gatto; Giuseppe Mazzarella; Pier Francesco Orrù; Andrea Volpi. 2017. "FMECA Modelling and Analysis in Blood Transfusion Chain." International Journal of Privacy and Health Information Management 5, no. 1: 23-39.
This study is part of a project which aims to study innovative RFID-based management systems, to optimise logistics in a blood transfusion centre (BTC). In 2009, an analysis of transfusion processes (AS IS 2009) and criticalities was carried out and a RFID-based process reengineering was performed (TO BE 2009). After several technical and management changes in BTC, a further process analysis was carried out and a new model (AS IS 2013) was implemented. The aim of the study is to evaluate efficiency and safety levels of BTC at present, and to compare the models using a coherent methodological approach. A failure modes, effects and criticalities analysis (FMECA) was carried out, in order to highlight criticalities related to patient safety and ad hoc key performance indicators (KPI) were designed and calculated for the two as is models. This paper describes a significant step prior to the design of UHF RFID systems.
Gianluca Borelli; Pier Francesco Orru'; Francesco Zedda. Performance analysis of a healthcare supply chain for RFID-enabled process reengineering. International Journal of Procurement Management 2015, 8, 169 .
AMA StyleGianluca Borelli, Pier Francesco Orru', Francesco Zedda. Performance analysis of a healthcare supply chain for RFID-enabled process reengineering. International Journal of Procurement Management. 2015; 8 (1/2):169.
Chicago/Turabian StyleGianluca Borelli; Pier Francesco Orru'; Francesco Zedda. 2015. "Performance analysis of a healthcare supply chain for RFID-enabled process reengineering." International Journal of Procurement Management 8, no. 1/2: 169.
An analysis of Electromagnetic Interference (EMI) between a Radio Frequency Identification (RFID) device and an Implantable Cardiac Defibrillator (ICD) is presented in this paper. In particular, the analysis focuses on the effects of EMI produced by an RFID reader on ICD operation. Thus, a brief overview of both ICD and RFID devices is presented at first. Subsequently, several experimental tests are performed inside an anechoic RF chamber, which ensures an appropriate shielding against external EMI sources. As a result, the comparison among ICD operating thresholds highlights its susceptibility against the RFID device.
Ivan Luigi Spano; Alessandro Serpi; Alessandro Fanti; Vincenzo Nissardi; Andrea Lai; Francesco Valentino Caredda; Pier Francesco Orrù; Giuseppe Mazzarella; Ignazio Marongiu; Gianluca Gatto. Electromagnetic compatibility analysis of RFID and implantable medical devices. 2014 22nd Telecommunications Forum Telfor (TELFOR) 2014, 818 -821.
AMA StyleIvan Luigi Spano, Alessandro Serpi, Alessandro Fanti, Vincenzo Nissardi, Andrea Lai, Francesco Valentino Caredda, Pier Francesco Orrù, Giuseppe Mazzarella, Ignazio Marongiu, Gianluca Gatto. Electromagnetic compatibility analysis of RFID and implantable medical devices. 2014 22nd Telecommunications Forum Telfor (TELFOR). 2014; ():818-821.
Chicago/Turabian StyleIvan Luigi Spano; Alessandro Serpi; Alessandro Fanti; Vincenzo Nissardi; Andrea Lai; Francesco Valentino Caredda; Pier Francesco Orrù; Giuseppe Mazzarella; Ignazio Marongiu; Gianluca Gatto. 2014. "Electromagnetic compatibility analysis of RFID and implantable medical devices." 2014 22nd Telecommunications Forum Telfor (TELFOR) , no. : 818-821.
In order to show that a given set of EM sources comply with national rules on exposition, a prediction model for EM propagation is needed. For indoor environment, the test presented her show that reflections and multipath can significantly affect the field level respect to the free-space situation, which sometimes can doubles.
F. V. Caredda; Alessandro Fanti; Gianluca Gatto; G. Mazzarella; Ivan Spano; E. Tanzi; P. F. Orru; F. Zedda. EM level evaluation in indoor environment. 2014 49th International Universities Power Engineering Conference (UPEC) 2014, 1 -4.
AMA StyleF. V. Caredda, Alessandro Fanti, Gianluca Gatto, G. Mazzarella, Ivan Spano, E. Tanzi, P. F. Orru, F. Zedda. EM level evaluation in indoor environment. 2014 49th International Universities Power Engineering Conference (UPEC). 2014; ():1-4.
Chicago/Turabian StyleF. V. Caredda; Alessandro Fanti; Gianluca Gatto; G. Mazzarella; Ivan Spano; E. Tanzi; P. F. Orru; F. Zedda. 2014. "EM level evaluation in indoor environment." 2014 49th International Universities Power Engineering Conference (UPEC) , no. : 1-4.
This paper deals with the analysis of the contact pressure distribution at the rod/guide bearing interface of a linear pneumatic actuator. The investigation was carried out both experimentally, using pressure‐sensitive film, and numerically by means of finite element analysis. By using the numerical model, it was possible to identify design changes to the cylinder front head whereby contact pressure at the bearing/rod interface can be redistributed. Operating conditions that are more advantageous in terms of wear and durability can thus be achieved.
Andrea Manuello Bertetto; L. Mazza; Pier Francesco Orru'. Contact Pressure Distribution in Guide Bearings for Pneumatic Actuators. Experimental Techniques 2013, 39, 46 -54.
AMA StyleAndrea Manuello Bertetto, L. Mazza, Pier Francesco Orru'. Contact Pressure Distribution in Guide Bearings for Pneumatic Actuators. Experimental Techniques. 2013; 39 (2):46-54.
Chicago/Turabian StyleAndrea Manuello Bertetto; L. Mazza; Pier Francesco Orru'. 2013. "Contact Pressure Distribution in Guide Bearings for Pneumatic Actuators." Experimental Techniques 39, no. 2: 46-54.
The present work aimed at giving a review of the end-of life phase for motor vehicles, providing accurate process modeling, indicating critical aspects, and finally suggesting improvements. For the study, one of the principal dismantler in Sardinia (Italy) was considered. The main innovation is the bottom-up approach to the problem; this was carried out by field observing the process activities and sharing the criticalities identification with the actors. The study has confirmed that the simplicity of disassembling the components and the ease of identification of the different materials to be separated is fundamental for an efficient dismantling of motor vehicles. It is finally crucial that the dismantling processes, being highly complicated, mainly involve the same manufacturers.
Carlo Enrico Carcangiu; Pier Francesco Orru'; Maria Teresa Pilloni. Analysis of End-of-Life Vehicle Processes: A Case Study in Sardinia (Italy). Lecture Notes in Control and Information Sciences 2010, 409 -416.
AMA StyleCarlo Enrico Carcangiu, Pier Francesco Orru', Maria Teresa Pilloni. Analysis of End-of-Life Vehicle Processes: A Case Study in Sardinia (Italy). Lecture Notes in Control and Information Sciences. 2010; ():409-416.
Chicago/Turabian StyleCarlo Enrico Carcangiu; Pier Francesco Orru'; Maria Teresa Pilloni. 2010. "Analysis of End-of-Life Vehicle Processes: A Case Study in Sardinia (Italy)." Lecture Notes in Control and Information Sciences , no. : 409-416.
The goal of the present work was to perform a thermal and fluid dynamic analysis of a refrigerated warehouse used for cheese conservation and ripening at a cheese factory close to the city of Cagliari. Air cooling is obtained by means of cooling units located under the cooler rooms ceiling, where the air distribution is realized by means of tubular pipes made of micro-porous material. An electronic control system allows keeping temperature and humidity within the desired range. As a first step, in order to verify the operation of the cooling system, an investigation was performed through a numerical simulation of the 3D and turbulent flow within the warehouse by solving the Reynolds Averaged Navier-Stokes (RANS) equations; this task was performed by employing the commercial code Fluent. The simulation allowed to represent the temperature and the velocity maps of the air flow inside the cooler room; the most relevant result mainly consists of a strong temperature gradient along the vertical direction. Some possible interventions for improving the air distribution are also suggested.
F. Cambuli; P. F. Orrù; M. T. Pilloni. Numerical Modeling of the Ventilation System for a Cooler Room. Volume 1: Advanced Energy Systems, Advanced Materials, Aerospace, Automation and Robotics, Noise Control and Acoustics, and Systems Engineering 2006, 2006, 423 -430.
AMA StyleF. Cambuli, P. F. Orrù, M. T. Pilloni. Numerical Modeling of the Ventilation System for a Cooler Room. Volume 1: Advanced Energy Systems, Advanced Materials, Aerospace, Automation and Robotics, Noise Control and Acoustics, and Systems Engineering. 2006; 2006 ():423-430.
Chicago/Turabian StyleF. Cambuli; P. F. Orrù; M. T. Pilloni. 2006. "Numerical Modeling of the Ventilation System for a Cooler Room." Volume 1: Advanced Energy Systems, Advanced Materials, Aerospace, Automation and Robotics, Noise Control and Acoustics, and Systems Engineering 2006, no. : 423-430.
The paper concerns an experimental study performed at a petrochemical plant of Enichem, located in Porto Torres, in the north western area of Sardinia. The investigation performed was centred on a steam cracking plant, the output of which is mainly composed of ethylene, propylene, pyrolytic benzine, hydrogen, methane and ethane. The study was focused on the problems concerning the maintenance of the plant components and the risks associated with the plant failures. The analysis, accomplished on a time interval of five years, from 1999 to 2004, enabled the characterization of the plant components and of the whole productive system from the point of view of the risk; this allowed to determine, in each year, which components are associated to the highest values of the risk, what is the behaviour of the most critical components during the five years under exam, which parts of the plant deserve a deeper attention and more resources and what kind of failures are the worst in terms of real damage produced. At the same time, a criticality analysis was performed employing both the MAGEC method and the Fuzzy Logic approach. The listing of the plant critical components based on the two methodologies employed places in the first positions the same components identified in the risk analysis. Nevertheless, in the results obtained through the risk analysis, some basic differences mainly due to the introduction of the basic economic aspects, are registered.
P. F. Orrù; M. T. Pilloni. An Investigation on the Failure Risks in a Steam Cracking Plant. Volume 1: Advanced Energy Systems, Advanced Materials, Aerospace, Automation and Robotics, Noise Control and Acoustics, and Systems Engineering 2006, 2006, 921 -929.
AMA StyleP. F. Orrù, M. T. Pilloni. An Investigation on the Failure Risks in a Steam Cracking Plant. Volume 1: Advanced Energy Systems, Advanced Materials, Aerospace, Automation and Robotics, Noise Control and Acoustics, and Systems Engineering. 2006; 2006 ():921-929.
Chicago/Turabian StyleP. F. Orrù; M. T. Pilloni. 2006. "An Investigation on the Failure Risks in a Steam Cracking Plant." Volume 1: Advanced Energy Systems, Advanced Materials, Aerospace, Automation and Robotics, Noise Control and Acoustics, and Systems Engineering 2006, no. : 921-929.
The application of an experimental technique based on ultrasonic waves to investigate contact parameters for a cylinder versus cylinder system in conformal configuration is proposed. The method analyses the ultrasonic reflection from the contact interface (or the transmission through it) and yields direct information about the size and shape of the nominal contact area; it also gives a qualitative indication of the contact pressure value, which is a parameter not explicitly related to the characteristics of the reflected wave. In order to assess the reliability of the technique as regards its ability to give a good reproduction of contact areas, the processed ultrasonic data, which can be easily represented as ‘contact maps’, were compared with the results of the application of a commercial pressure-sensitive film (Fuji Prescale HS). At the same time, a finite element model of the tested contact configuration supplied a further comparison term useful in assessing the effectiveness of the ultrasonic technique as a tool in estimating contact pressure distribution.
Massimiliano Pau; A Baldi; P F Orrù; F Ginesu. Experimental investigation on contact between cylindrical conformal surfaces. The Journal of Strain Analysis for Engineering Design 2004, 39, 315 -328.
AMA StyleMassimiliano Pau, A Baldi, P F Orrù, F Ginesu. Experimental investigation on contact between cylindrical conformal surfaces. The Journal of Strain Analysis for Engineering Design. 2004; 39 (3):315-328.
Chicago/Turabian StyleMassimiliano Pau; A Baldi; P F Orrù; F Ginesu. 2004. "Experimental investigation on contact between cylindrical conformal surfaces." The Journal of Strain Analysis for Engineering Design 39, no. 3: 315-328.
Experimental Techniques and Design in Composite Materials 5: Prediction of the Dynamic Response of Impacted Composite Laminates
Francesco Aymerich; Pier Francesco Orru'; Pierluigi Priolo. Prediction of the Dynamic Response of Impacted Composite Laminates. Key Engineering Materials 2001, 221-222, 197 -208.
AMA StyleFrancesco Aymerich, Pier Francesco Orru', Pierluigi Priolo. Prediction of the Dynamic Response of Impacted Composite Laminates. Key Engineering Materials. 2001; 221-222 ():197-208.
Chicago/Turabian StyleFrancesco Aymerich; Pier Francesco Orru'; Pierluigi Priolo. 2001. "Prediction of the Dynamic Response of Impacted Composite Laminates." Key Engineering Materials 221-222, no. : 197-208.