39 research outputs found

    A Distributed Software Platform for Additive Manufacturing

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    Additive Manufacturing (AM), a cornerstone of Industry 4.0, is expected to revolutionise production in practically all industries. However, multiple production challenges still exist, preventing its diffusion. In recent years, Machine Learning algorithms have been employed to overcome these hurdles. Nonetheless, the usage of these algorithms is constrained by the scarcity of data together with the challenges associated with accessing and integrating the information generated during the AM pipeline. In this work, we present a vendor-agnostic platform for AM that enables collecting, storing, analysing and linking the heterogeneous data of the complete AM process. We conducted an extensive analysis of the different AM datatypes and identified the most suitable technologies for storing them. Furthermore, we performed an in-depth study of the requirements of different AM stakeholders to develop a rich and intuitive Graphical User Interface. We showcased the specific usage of the platform for Powder Bed Fusion, one of the most popular AM processes, in a real industrial scenario, integrating specific existing modules for in-situ monitoring and real-time defect detection

    A Comparison Analysis of BLE-Based Algorithms for Localization in Industrial Environments

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    Proximity beacons are small, low-power devices capable of transmitting information at a limited distance via Bluetooth low energy protocol. These beacons are typically used to broadcast small amounts of location-dependent data (e.g., advertisements) or to detect nearby objects. However, researchers have shown that beacons can also be used for indoor localization converting the received signal strength indication (RSSI) to distance information. In this work, we study the effectiveness of proximity beacons for accurately locating objects within a manufacturing plant by performing extensive experiments in a real industrial environment. To this purpose, we compare localization algorithms based either on trilateration or environment fingerprinting combined with a machine-learning based regressor (k-nearest neighbors, support-vector machines, or multi-layer perceptron). Each algorithm is analyzed in two different types of industrial environments. For each environment, various configurations are explored, where a configuration is characterized by the number of beacons per square meter and the density of fingerprint points. In addition, the fingerprinting approach is based on a preliminary site characterization; it may lead to location errors in the presence of environment variations (e.g., movements of large objects). For this reason, the robustness of fingerprinting algorithms against such variations is also assessed. Our results show that fingerprint solutions outperform trilateration, showing also a good resilience to environmental variations. Given the similar error obtained by all three fingerprint approaches, we conclude that k-NN is the preferable algorithm due to its simple deployment and low number of hyper-parameters

    Image analytics and machine learning for in-situ defects detection in Additive Manufacturing

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    In the context of Industry 4.0, metal Additive Manufacturing (AM) is considered a promising technology for medical, aerospace and automotive fields. However, the lack of assurance of the quality of the printed parts can be an obstacle for a larger diffusion in industry. To this date, AM is most of the times a trial-and-error process, where the faulty artefacts are detected only after the end of part production. This impacts on the processing time and overall costs of the process. A possible solution to this problem is the in-situ monitoring and detection of defects, taking advantage of the layer-by-layer nature of the build. In this paper, we describe a system for in-situ defects monitoring and detection for metal Powder Bed Fusion (PBF), that leverages an off-axis camera mounted on top of the machine. A set of fully automated algorithms based on Computer Vision and Machine Learning allow the timely detection of a number of powder bed defects and the monitoring of the object's profile for the entire duration of the build

    Growth and rupture of an intracranial aneurysm: the role of wall aneurysmal enhancement and CD68+

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    IntroductionIntracranial aneurysms occur in 3%–5% of the general population. While the precise biological mechanisms underlying the formation, growth, and sudden rupture of intracranial aneurysms remain partially unknown, recent research has shed light on the potential role of inflammation in aneurysm development and rupture. In addition, there are ongoing investigations exploring the feasibility of employing new drug therapies for controlling the risk factors associated with aneurysms. CD68, a glycosylated glycoprotein and the human homolog of macrosialin, is prominently expressed in monocyte/macrophages within inflamed tissues and has shown potential application in oncology. An observational study was conducted with the aim of comparing the histological characteristics of aneurysm walls with preoperative MRI scans, specifically focusing on CD68 activity.MethodAn observational pilot study was conducted to investigate the histological characteristics of the aneurysm wall that could be potentially associated with aneurysm growth and rupture. A total of 22 patients diagnosed with ruptured and unruptured intracranial aneurysms who had undergone conventional clipping between January 2017 and December 2022 were included in the study.ResultsA histopathological analysis of the aneurysm wall was performed in all patients, particularly focusing on the presence of CD68. A preoperative MRI with gadolinium was conducted in 10 patients with unruptured aneurysms and six patients with ruptured aneurysms. An emergency clipping was performed in the remaining six patients. The results showed that CD68 positivity and wall enhancement were significantly associated with intracranial aneurysm wall degeneration, growth, and rupture.ConclusionThe histological and radiological inflammatory findings observed in the wall of cerebral aneurysms, as well as the CD68 positivity, are significantly associated with the risk of intracranial aneurysm growth and rupture. This study highlights the crucial importance of considering clinical and medical data when making treatment decisions for intracranial aneurysms. Furthermore, it emphasizes the relevance of evaluating wall enhancement in MRI scans as part of the diagnostic and prognostic process

    In-situ defect detection of metal Additive Manufacturing: an integrated framework

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    Metal Additive Manufacturing (AM) is a pillar of the Industry 4.0, with many attractive advantages compared to traditional subtractive fabrication technologies. However, there are many quality issues that can be an obstacle for mass production. The in-situ camera-based monitoring and detection of defects, taking advantage of the layer-by-layer nature of the build, can be an effective solution to this problem. In this context, the use of Computer Vision and Machine Learning algorithms have a very important role. Nonetheless, they are up to this date limited by the scarcity of data for the training, as well as by the difficulty of accessing and integrating the AM process data throughout the fabrication. To tackle this problem, this paper proposes a system for in-situ monitoring that analyses images from an off-axis camera mounted on top of the machine to detect the arising defects in real-time, with automated generation of synthetic images based on Generative Adversarial Network (GAN) for dataset augmentation purposes. The computing functionalities are embedded into a holistic distributed AM platform allowing the collection, integration and storage of data at all stages of the AM pipeline

    MR imaging of primary benign cardiac tumors in the pediatric population

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    Primary cardiac tumors are rare in all ages, especially in children, with a reported prevalence range of 0.0017–0.28% in autopsy series. Due to their rarity, the diagnostic and therapeutic pathways reserved to them are usually described by single case reports, leading to the point where a common diagnostic protocol is imperative to obtain a differential diagnosis. The first diagnostic approach is done with transthoracic echocardiogram (TTE), due to its wide availability, low cost, absence of ionizing radiations and non-invasiveness. Several tumors are discovered incidentally and, in many cases, TTE is helpful to determine location, size and anatomical features, playing a key role in the differential diagnosis. In the last few years, cardiac magnetic resonance imaging (CMR) has had an increased role in the diagnostic pathway of pediatric cardiac masses, due to its high accuracy in characterizing mass tissue properties (especially for soft tissue), and in detecting tumor size, extent, pericardial/pleural effusion, leading to the correct diagnosis, treatment and follow-up. Therefore, nowadays, several consensus statements consider CMR as a leading imaging technique, thanks to its non-invasive tissue characterization, without the use of ionizing radiation, in an unrestricted field of view. As suggested by the most recent literature, the pediatric protocol is not so different from the adult one, adapted to the size and cardiac frequency of the patient, sometimes requiring special conditions such as free-breathing sequences and/or sedation or general anesthesia in non-cooperating patients.</p

    Anomalous venoatrial connections – CT and MRI assessment

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    Abnormal venous atrial (VA) connections present a congenital heart disease (CHD) challenge for pediatric cardiologists. Fully anatomical evaluation is very difficult in prenatal and perinatal follow-up, but it has a profound impact on surgical correction and outcome. The echocardiogram is first-line imaging and represents the gold standard tool for simple abnormal VA connection. CT and MRI are mandatory for more complex heart disease and “nightmare cases”. 3D post-processing of volumetric CT and MRI acquisition helps to clarify anatomical relationships and allows for the creation of 3D printing models that can become crucial in customizing surgical strategy. Our article describes a ten-year (2013–2022) tertiary referral CHD center of abnormal AV connections investigated with CT and MRI, illustrating most of these complex diseases with the help of volume rendering (VR) or multiplanar reconstructions (MPR). The nightmarish cases will also be addressed due to the complex cardiovascular arrangement that requires a challenging surgical solution for correction along with the post-surgical complications.</p

    Clinical features and outcomes of elderly hospitalised patients with chronic obstructive pulmonary disease, heart failure or both

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    Background and objective: Chronic obstructive pulmonary disease (COPD) and heart failure (HF) mutually increase the risk of being present in the same patient, especially if older. Whether or not this coexistence may be associated with a worse prognosis is debated. Therefore, employing data derived from the REPOSI register, we evaluated the clinical features and outcomes in a population of elderly patients admitted to internal medicine wards and having COPD, HF or COPD + HF. Methods: We measured socio-demographic and anthropometric characteristics, severity and prevalence of comorbidities, clinical and laboratory features during hospitalization, mood disorders, functional independence, drug prescriptions and discharge destination. The primary study outcome was the risk of death. Results: We considered 2,343 elderly hospitalized patients (median age 81&nbsp;years), of whom 1,154 (49%) had COPD, 813 (35%) HF, and 376 (16%) COPD + HF. Patients with COPD + HF had different characteristics than those with COPD or HF, such as a higher prevalence of previous hospitalizations, comorbidities (especially chronic kidney disease), higher respiratory rate at admission and number of prescribed drugs. Patients with COPD + HF (hazard ratio HR 1.74, 95% confidence intervals CI 1.16-2.61) and patients with dementia (HR 1.75, 95% CI 1.06-2.90) had a higher risk of death at one year. The Kaplan-Meier curves showed a higher mortality risk in the group of patients with COPD + HF for all causes (p = 0.010), respiratory causes (p = 0.006), cardiovascular causes (p = 0.046) and respiratory plus cardiovascular causes (p = 0.009). Conclusion: In this real-life cohort of hospitalized elderly patients, the coexistence of COPD and HF significantly worsened prognosis at one year. This finding may help to better define the care needs of this population

    La gestione elettronica dei clienti, l'impatto dei sistemi eCRM nelle PMI

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    Il presente lavoro di tesi, ha avuto lo scopo di analizzare quello che potrebbe essere l’impatto dei sistemi eCRM nelle pmi, e capirne quali vantaggi e o benefici potrebbe portare una installazione di un tale sistema in una realtà di piccole dimensioni. Quindi, in primis sono stati introdotti quelli che sono i sistemi informativi aziendali e definita l’importanza delle informazioni in azienda. Informazioni che, in tempi precedenti viaggiavano tramite dei sistemi aziendali chiamati legacy, fino ad arrivare ai più recenti sistemi ERP, sistemi che caratterizzano il loro grande vantaggio nella capacità di usare una sola informazione per tutto il sistema, quindi a differenza dei legacy qui si trova un database per tutta la realtà aziendale. Questi sistemi ERP si appoggiano in seguito a dei sistemi chiamati ERP II, i sistemi ERP II non sono altro che sistemi estesi. Si definiscono estesi poiché danno la possibilità di poter far confluire informazioni dall’ambiente esterno fino all’azienda. Esempio di questi ERP II sono i sistemi SCM, PLM e CRM. I sistemi CRM sono i sistemi che si occupano della gestione dei rapporti con la clientela con i relativi vantaggi, gestione della clientela che attraverso l’introduzione dei canali elettronici (web, social) permette la gestione. Tutto questo potrebbe portare dei vantaggi alle più piccole realtà a cui non è sempre facile implementare dei sistemi così complicati This thesis was aimed at analyzing what the impact of eCRM systems could be in SMEs, and understanding what advantages and or benefits an installation of such a system could bring to a small-scale reality. So, first of all what are the corporate information systems were introduced and the importance of information in the company was defined. Information that, in previous times, traveled through company systems called legacy, up to the most recent ERP systems, systems that characterize their great advantage in the ability to use a single information for the whole system, so unlike legacy here it is a database for the whole company. These ERP systems later rely on systems called ERP II, ERP II systems are nothing more than extended systems. They are defined as extended because they give the possibility of being able to bring information from the external environment to the company. Example of these ERP II are the SCM, PLM and CRM systems. CRM systems are systems that deal with the management of customer relations with the related advantages, customer management which, through the introduction of electronic channels (web, social), allows management. All this could bring advantages to the smallest companies which are not always easy to implement such complicated system
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