Detailed energy analysis of a sheet-metal-forming press from electrical measurements

This paper presents a methodology that allows for the detection of the state of a sheet-metal-forming press, the parts being produced, their cadence, and the energy demand for each unit produced. For this purpose, only electrical measurements are used. The proposed analysis is conducted at the level of the press subsystems: main motor, transfer module, cushion, and auxiliary systems, and is intended to count, classify, and monitor the production of pressed parts. The power data are collected every 20 ms and show cyclic behavior, which is the basis for the presented methodology. A neural network (NN) based on heuristic rules is developed to estimate the press states. Then, the production period is determined from the power data using a least squares method to obtain normalized harmonic coefficients. These are the basis for a second NN dedicated to identifying the parts in production. The global error in estimating the parts being produced is under 1%. The resulting information could be handy in determining relevant information regarding the press behavior, such as energy per part, which is necessary in order to evaluate the energy performance of the press under different production conditions.Xunta de Galicia | Ref. IN854A 2020/0

Modeling and simulation of household appliances power consumption

The consumption of household appliances tends to increase. Therefore, the application of energy efficiency measurements is urgently needed to reduce the levels of power consumption. Over the last years, various methods have been used to predict household electricity consumption. As a novelty, this paper proposed a method of predicting the consumption of household appliances by evaluating statistical distributions (Kolmogorov–Smirnov Test and Pearson’s X2 test). To test the veracity of the evaluations, first, a set of random values was simulated for each hour, and their respective averages were calculated. These were compared with the averages of the real values for each hour. With the exception of HVAC during working days, great results were obtained. For the refrigerator, the maximum error was 3.91%, while for the lighting, it was 4.27%. At the point of consumption, the accuracy was even higher, with an error of 1.17% for the dryer while for the washing machine and dishwasher, their minimum errors were less than 1%. The error results confirm that the applied methodology is perfectly acceptable for modeling household appliance consumption and consequently predicting it. However, these consumptions can be only extrapolated to dwellings with similar surface areas and habitats

The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study

AimThe SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery.MethodsThis was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin.ResultsOverall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P ConclusionOne in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease

Safety of hospital discharge before return of bowel function after elective colorectal surgery

© 2020 BJS Society Ltd Published by John Wiley & Sons LtdBackground: Ileus is common after colorectal surgery and is associated with an increased risk of postoperative complications. Identifying features of normal bowel recovery and the appropriateness for hospital discharge is challenging. This study explored the safety of hospital discharge before the return of bowel function. Methods: A prospective, multicentre cohort study was undertaken across an international collaborative network. Adult patients undergoing elective colorectal resection between January and April 2018 were included. The main outcome of interest was readmission to hospital within 30 days of surgery. The impact of discharge timing according to the return of bowel function was explored using multivariable regression analysis. Other outcomes were postoperative complications within 30 days of surgery, measured using the Clavien–Dindo classification system. Results: A total of 3288 patients were included in the analysis, of whom 301 (9·2 per cent) were discharged before the return of bowel function. The median duration of hospital stay for patients discharged before and after return of bowel function was 5 (i.q.r. 4–7) and 7 (6–8) days respectively (P < 0·001). There were no significant differences in rates of readmission between these groups (6·6 versus 8·0 per cent; P = 0·499), and this remained the case after multivariable adjustment for baseline differences (odds ratio 0·90, 95 per cent c.i. 0·55 to 1·46; P = 0·659). Rates of postoperative complications were also similar in those discharged before versus after return of bowel function (minor: 34·7 versus 39·5 per cent; major 3·3 versus 3·4 per cent; P = 0·110). Conclusion: Discharge before return of bowel function after elective colorectal surgery appears to be safe in appropriately selected patients

Safety of hospital discharge before return of bowel function after elective colorectal surgery

Background: Ileus is common after colorectal surgery and is associated with an increased risk of postoperative complications. Identifying features of normal bowel recovery and the appropriateness for hospital discharge is challenging. This study explored the safety of hospital discharge before the return of bowel function.Methods: A prospective, multicentre cohort study was undertaken across an international collaborative network. Adult patients undergoing elective colorectal resection between January and April 2018 were included. The main outcome of interest was readmission to hospital within 30 days of surgery. The impact of discharge timing according to the return of bowel function was explored using multivariable regression analysis. Other outcomes were postoperative complications within 30 days of surgery, measured using the Clavien-Dindo classification system.Results: A total of 3288 patients were included in the analysis, of whom 301 (9.2 per cent) were discharged before the return of bowel function. The median duration of hospital stay for patients discharged before and after return of bowel function was 5 (i.q.r. 4-7) and 7 (6-8) days respectively (P &lt; 0.001). There were no significant differences in rates of readmission between these groups (6.6 versus 8.0 per cent; P = 0.499), and this remained the case after multivariable adjustment for baseline differences (odds ratio 0.90, 95 per cent c.i. 0.55 to 1.46; P = 0.659). Rates of postoperative complications were also similar in those discharged before versus after return of bowel function (minor: 34.7 versus 39.5 per cent; major 3.3 versus 3.4 per cent; P = 0.110).Conclusion: Discharge before return of bowel function after elective colorectal surgery appears to be safe in appropriately selected patients

Timing of nasogastric tube insertion and the risk of postoperative pneumonia: an international, prospective cohort study

Aim: Aspiration is a common cause of pneumonia in patients with postoperative ileus. Insertion of a nasogastric tube (NGT) is often performed, but this can be distressing. The aim of this study was to determine whether the timing of NGT insertion after surgery (before versus after vomiting) was associated with reduced rates of pneumonia in patients undergoing elective colorectal surgery. Method: This was a preplanned secondary analysis of a multicentre, prospective cohort study. Patients undergoing elective colorectal surgery between January 2018 and April 2018 were eligible. Those receiving a NGT were divided into three groups, based on the timing of the insertion: routine NGT (inserted at the time of surgery), prophylactic NGT (inserted after surgery but before vomiting) and reactive NGT (inserted after surgery and after vomiting). The primary outcome was the development of pneumonia within 30 days of surgery, which was compared between the prophylactic and reactive NGT groups using multivariable regression analysis. Results: A total of 4715 patients were included in the analysis and 1536 (32.6%) received a NGT. These were classified as routine in 926 (60.3%), reactive in 461 (30.0%) and prophylactic in 149 (9.7%). Two hundred patients (4.2%) developed pneumonia (no NGT 2.7%; routine NGT 5.2%; reactive NGT 10.6%; prophylactic NGT 11.4%). After adjustment for confounding factors, no significant difference in pneumonia rates was detected between the prophylactic and reactive NGT groups (odds ratio 1.03, 95% CI 0.56–1.87, P = 0.932). Conclusion: In patients who required the insertion of a NGT after surgery, prophylactic insertion was not associated with fewer cases of pneumonia within 30 days of surgery compared with reactive insertion