59 research outputs found
A systematic mapping of the advancing use of machine learning techniques for predictive maintenance in the manufacturing sector
The increasing availability of data, gathered by sensors and intelligent machines, is chang-ing the way decisions are made in the manufacturing sector. In particular, based on predictive approach and facilitated by the nowadays growing capabilities of hardware, cloud-based solutions, and new learning approaches, maintenance can be scheduled—over cell engagement and resource monitoring—when required, for minimizing (or managing) unexpected equipment failures, improving uptime through less aggressive maintenance schedules, shortening unplanned downtime, reducing excess (direct and indirect) cost, reducing long-term damage to machines and processes, and improve safety plans. With access to increased levels of data (and over learning mechanisms), companies have the capability to conduct statistical tests using machine learning algorithms, in order to uncover root causes of problems previously unknown. This study analyses the maturity level and contributions of machine learning methods for predictive maintenance. An upward trend in publications for predictive maintenance using machine learning techniques was identified with the USA and China leading. A mapping study—steady set until early 2019 data—was employed as a formal and well-structured method to synthesize material and to report on pervasive areas of research. Type of equipment, sensors, and data are mapped to properly assist new researchers in positioning new research activities in the domain of smart maintenance. Hence, in this paper, we focus on data-driven methods for predictive maintenance (PdM) with a comprehensive survey on applications and methods until, for the sake of commenting on stable proposal, 2019 (early included). An equal repartition between evaluation and validation studies was identified, this being a symptom of an immature but growing research area. In addition, the type of contribution is mainly in the form of models and methodologies. Vibrational signal was marked as the most used data set for diagnosis in manufacturing machinery monitoring; furthermore, supervised learning is reported as the most used predictive approach (ensemble learning is growing fast). Neural networks, followed by random forests and support vector machines, were identified as the most applied methods encompassing 40% of publications, of which 67% related to deep neural network with long short-term memory predominance. Notwithstanding, there is no robust approach (no one reported optimal performance over different case tests) that works best for every problem. We finally conclude the research in this area is moving fast to gather a separate focused analysis over the last two years (whenever stable implementations will appear)
Utility of preoperative neutrophil/lymphocyte ratio as a new objective prognostic tool in endoscopically treated upper tract urothelial carcinoma. A retrospective evaluation
Introduction: This exploratory retrospective analysis examined any potential prognostic role of preoperative neutrophil lymphocyte ratio (NLR) for progression-free survival (PFS) and time to endoscopically verified upper tract or bladder recurrence-free survival (RFS) in upper tract urothelial cancer (UTUC) patients selected for endoscopic treatment with subsequent endosurveillance. Patients and Methods: Eligibility criteria were natural orifice endoscopically retrogradely treated low-risk and imperative UTUC patients treated between 2005 and 2019, with biopsy confirmed diagnosis and 12 months minimum follow-up. For PFS, optimal NLR cutoff value was derived by log-rank test. Subsequently, both PFS and RFS were assessed for differences using Kaplan-Meier survival curves and log-rank test. Multivariate proportional Cox regression analysis adjusted for clinicopathologic variables was performed to examine end points for NLR-independent prognostic significance. Results: There were 100 eligible patients (63 truly low risk and 37 imperative cases). The optimal PFS log-rank test NLR cutoff value was 2.7. NLR ≥2.7 was significantly associated with shorter PFS (p = 0.01), and shorter upper tract RFS (p = 0.03), but not with bladder RFS (p = 0.90). Only positive high-grade cytology (hazard ratio [HR] 5.92, 95% confidence interval [CI] 2.140-16.35, p = 0.002) and NLR ≥2.7 (HR 4.28, 95% CI 1.34-13.72, p = 0.014) independently predicted PFS in multivariate analysis. Recurrence and progression were not significantly linked in the low-risk subset. Conclusions: This exploratory analysis showed that baseline NLR evaluation before first endoscopic UTUC treatment may be a valuable predictor and prognosticator of defined disease progression and of upper tract recurrence risk. In conjunction with high-grade urine cytology, NLR may improve risk stratification to optimize future individualized management
Higher testosterone serum levels are associated with a higher childbirth in patients treated for testicular cancer
Aim of our study was to assess fertility of patients treated with orchifunicolectomy for testicular cancer. A retrospective analysis of patients undergoing orchifunicolectomy for testicular cancer was conducted in three centers from 2000 to 2019. Demographic, clinical and histological
characteristics of the patients were recorded. Adjuvant treatments were recorded. Number of pregnancies, number of children, cryopreservation, in vitro fertilization were recorded as well as postoperative testosterone serum level. Risk factors for pregnancy were evaluated. Univariate and multivariate analysis were performed to evaluate factors influencing pregnancy rates
Effect of vacation on urinary symptoms in healthcare workers. An Italian multicenter study
Aim of our study was to assess the impact of vacation on urinary symptoms in health care workers. Between March 2018 to October 2019 a survey was carried out by enrolling health care system workers in three centers. Demographic and clinical characteristics of health care workers (i.e. age, smoking status, medical history) were collected. Urinary symptoms work related quality of life and health were
assessed before and after two weeks’ vacation with validated questionnaires: Overactive Bladder Questionnaire Short Form (OABqsf), nocturia episodes,Work-relatedQuality of Life (WRQOL) and SF-36 questionnaires. As well, NS workers (NSWs), defined as working at
least one time aweek from 8 pmto 8 am,were compared to traditional workers (TWs). Wilcoxon rank test was performed to test significant
differences before and after vacation. Mann Whitney test was performed to assess differences between NSWs and TWs
Kidney transplantation from living donor with monolateral renal artery fibromuscular dysplasia using a cryopreserved iliac graft for arterial reconstruction: a case report and review of the literature
Background Aging and mortality of patients on waiting lists for kidney transplantation have increased, as a result of the shortage of organs available all over the world. Living donor grafts represent a significant source to maintain the donor pool, and resorting successfully to allografts with arterial disease has become a necessity. The incidence of renal artery fibromuscular dysplasia (FMD) in potential living renal donors is reported to be 2-6%, and up to 4% of them present concurrent extra-renal involvement. Case presentation We present a case of renal transplantation using a kidney from a living donor with monolateral FMD. Resection of the affected arterial segment and its subsequent replacement with a cryopreserved iliac artery graft from a deceased donor were performed. No intraoperative nor post-operative complications were reported. The allograft function promptly resumed, with satisfying creatinine clearance, and adequate patency of the vascular anastomoses was detected by Doppler ultrasounds. Conclusion Literature lacks clear guidelines on the eligibility of potential living renal donors with asymptomatic FMD. Preliminary assessment of the FMD living donor should always rule out any extra-renal involvement. Whenever possible, resection and reconstruction of the affected arterial segment should be taken into consideration as this condition may progress after implantation
Incidence and clinical predictors of a subsequent nonmelanoma skin cancer in solid organ transplant recipients with a first nonmelanoma skin cancer: a multicenter cohort study.
Objective: To compare the long-term risk of primary nonmelanoma
skin cancer (NMSC) and the risk of subsequent
NMSC in kidney and heart transplant recipients.
Design: Partially retrospective cohort study.
Setting: Two Italian transplantation centers.
Patients: The study included 1934 patients: 1476 renal
transplant recipients and 458 heart transplant recipients.
Main Outcome Measures: Cumulative incidences and
risk factors of the first and subsequent NMSCs.
Results: Two hundred patients developed a first NMSC
after a median follow-up of 6.8 years after transplantation.
The 3-year risk of the primary NMSC was 2.1%. Of
the 200 patients with a primary NMSC, 91 (45.5%) had a
secondNMSCafter a median follow-up after the firstNMSC
of 1.4 years (range, 3 months to 10 years). The 3-year risk
of a second NMSC was 32.2%, and it was 49 times higher
than that in patients with no previous NMSC. In a Cox
proportional hazards regression model, age older than 50
years at the time of transplantation and male sex were significantly
related to the first NMSC. Occurrence of the subsequent
NMSC was not related to any risk factor considered,
including sex, age at transplantation, type of
transplanted organ, type of immunosuppressive therapy,
histologic type of the first NMSC, and time since diagnosis
of the first NMSC. Histologic type of the first NMSC
strongly predicted the type of the subsequent NMSC.
Conclusions: Development of a first NMSC confers a
high risk of a subsequent NMSC in transplant recipients.
Intensive long-term dermatologic follow-up of these
patients is advisable
A Systematic Review of the Efficacy and Toxicity of Brachytherapy Boost Combined with External Beam Radiotherapy for Nonmetastatic Prostate Cancer
Context
The optimum use of brachytherapy (BT) combined with external beam radiotherapy (EBRT) for localised/locally advanced prostate cancer (PCa) remains uncertain.
Objective
To perform a systematic review to determine the benefits and harms of EBRT-BT.
Evidence acquisition
Ovid MEDLINE, Embase, and EBM Reviews—Cochrane Central Register of Controlled Trials databases were systematically searched for studies published between January 1, 2000 and June 7, 2022, according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Eligible studies compared low- or high-dose-rate EBRT-BT against EBRT ± androgen deprivation therapy (ADT) and/or radical prostatectomy (RP) ± postoperative radiotherapy (RP ± EBRT). The main outcomes were biochemical progression-free survival (bPFS), severe late genitourinary (GU)/gastrointestinal toxicity, metastasis-free survival (MFS), cancer-specific survival (CSS), and overall survival (OS), at/beyond 5 yr. Risk of bias was assessed and confounding assessment was performed. A meta-analysis was performed for randomised controlled trials (RCTs).
Evidence synthesis
Seventy-three studies were included (two RCTs, seven prospective studies, and 64 retrospective studies). Most studies included participants with intermediate-or high-risk PCa. Most studies, including both RCTs, used ADT with EBRT-BT. Generally, EBRT-BT was associated with improved bPFS compared with EBRT, but similar MFS, CSS, and OS. A meta-analysis of the two RCTs showed superior bPFS with EBRT-BT (estimated fixed-effect hazard ratio [HR] 0.54 [95% confidence interval {CI} 0.40–0.72], p < 0.001), with absolute improvements in bPFS at 5–6 yr of 4.9–16%. However, no difference was seen for MFS (HR 0.84 [95% CI 0.53–1.28], p = 0.4) or OS (HR 0.87 [95% CI 0.63–1.19], p = 0.4). Fewer studies examined RP ± EBRT. There is an increased risk of severe late GU toxicity, especially with low-dose-rate EBRT-BT, with some evidence of increased prevalence of severe GU toxicity at 5–6 yr of 6.4–7% across the two RCTs.
Conclusions
EBRT-BT can be considered for unfavourable intermediate/high-risk localised/locally advanced PCa in patients with good urinary function, although the strength of this recommendation based on the European Association of Urology guideline methodology is weak given that it is based on improvements in biochemical control.
Patient summary
We found good evidence that radiotherapy combined with brachytherapy keeps prostate cancer controlled for longer, but it could lead to worse urinary side effects than radiotherapy without brachytherapy, and its impact on cancer spread and patient survival is less clear
Reinforcement Learning for Resource Allocation in Cloud Datacenter
Cloud technologies provide capabilities that can guarantee to the end user high availability, performance and scalability. However, the growing use of IoT technologies and devices, have made the applications not only more computationally intensive, but also data intensive. Because of this, dynamically scaling applications running on clouds can lead to varied and unpredictable results due to highly time-varying workloads distinguishes this new kind of applications. These applications are also often composed of different independent modules that could be easily moved across devices. Automatic scheduling and allocation of these modules is not an easy task, because there could be many conditions that prevent the design of a smart solutions. Thus determining appropriate scaling policies in a dynamic non-stationary environment is non-trivial, as a problem arises concerning resource allocation. Decision making about which resources should be added and removed, when the underlying performance of the resource is in a constant state of flux, becomes an issues. In this work we model both the applications and the infrastructure in order to formulate e Reinforcement Learning problem for automatically find the best configuration for the applications modules, taking into account the environment in which they are placed and the applications already running
A methodology and implementing tool for semantic business process annotation
The task of accurately model Business Process is steadily growing in complicatedness, partially due to the ever changing and dynamic contexts such processes are defined into, and the complexity of domain-specific concepts characterizing today’s global economic environment. Even though the modern IT provides several tools to help the Business Process modellers, they often do not offer sufficient support to the definition and interpretation of domain concepts or relationships, due to a general lack of precise domain knowledge and ambiguities in the terms used to define such concepts. Such semantic ambiguity negatively affects the efficiency and quality of Business Process modelling. To address these issues, an ontology based approach is proposed to mitigate semantic ambiguity, and a means to capture rich, semantic information on complex Business Processes through domain specific ontologies is presented. Also, a prototype tool which allows users to annotate existing BPMN models is described
Towards an integrated internet of things: Current approaches and challenges
With the diffusion of sensors and smart devices, and the advances in connection technologies, the Internet of Things (IoT) has become a very popular topic. Because of the creation and expansion of new and existing sensor networks, the need to define a common standard for sensors’ interfaces representation has arisen. Currently it is difficult to make different sensors and sensors’ networks interoperate seamlessly, since their interfaces are not always well specified or are not ready to be adapted immediately to one another. In this chapter we will introduce the main technologies currently available to define a machine readable and human comprehensible IoT API, and we will point out the several challenges which will derive from an automatic analysis and description of IoT interfaces. Security issues are also considered and discussed
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