The Pareto Analysis for Establishing Content Criteria in Surgical Training

Screening of Discrete Wavelet Transform Parameters for the Denoising of Rolling Bearing Signals in Presence of Localised Defects

Maintenance scheduling is a fundamental element in industry, where excessive downtime can lead to considerable economic losses. Active monitoring systems of various components are ever more used, and rolling bearings can be identified as one of the primary causes of failure on production lines. Vibration signals extracted from bearings are affected by noise, which can make their nature unclear and the extraction and classification of features difficult. In recent years, the use of the discrete wavelet transform for denoising has been increasing, but studies in the literature that optimise all the parameters used in this process are lacking. In the current article, the authors present an algorithm to optimise the parameters required for denoising based on the discrete wavelet transform and thresholding. One-hundred sixty different configurations of the mother wavelet, threshold evaluation method, and threshold function are compared on the Case Western Reserve University database to obtain the best combination for bearing damage identification with an iterative method and are evaluated with tradeoff and kurtosis. The analysis results show that the best combination of parameters for denoising is dmey, rigrSURE, and the hard threshold. The signals were then distributed in a 2D plane for classification through an algorithm based on principal component analysis, which uses a preselection of features extracted in the time domain.

Performance of HIV detection in Zhejiang province in China: The Pareto principle at work

Background

Timely detection of HIV infection is critical for curbing the AIDS epidemic, and building an extensive and effective HIV laboratory network is of great importance. Therefore, improving quality management of the laboratory network and optimizing detection strategies are desirable research issues.

Methods

We assessed the applicability of the Pareto principle to HIV detection performance. We conducted a retrospective review of basic information and numbers of screening tests among an HIV laboratory network (1,452 laboratories) in Zhejiang province in 2014 and statistically analyzed HIV testing data for different population categories.

Results

Approximately, 80% of the cumulative HIV screening tests and positive screening tests originated from 17.3% (251/1,452) and 11.7% (170/1,452) of the laboratories in the whole province, respectively, and similar patterns were observed at the prefectural level. We found that the top five population screening categories (25%, 5/20) had the highest contribution (approximately 80%) to not only the number of screening tests (77.2%) but also the numbers of positive (76.4%) and confirmed positive tests (81.5%).

Conclusions

The Pareto principle provides a method for identifying noteworthy laboratories to deliver prior quality supervision and developing highly efficient screening strategies that best suit local needs.

Mixed methods analysis of factors influencing change in clinical behaviours of non-physician anaesthetists in Kenya following obstetric anaesthesia training

Maternal mortality rates in low-middle income countries remain high, with sub-Saharan Africa accounting for two-thirds of global maternal deaths. Inadequate staff training is one of the main contributors to anaesthesia-related deaths and the Association of Anaesthetists developed the Safe Anaesthesia from Education course in collaboration with the World Federation of Societies of Anaesthesiologists to address this training gap. We aimed to evaluate the impact of this course among Kenyan participants. Mixed methodologies and secondary analyses of anonymised data were used to study translation of learning into practice. In total, 103 participants from 66 facilities who attended courses between 2016 and 2017 were analysed. Ninety (87%) participants who were followed up completed knowledge tests. Baseline median (IQR [range]) knowledge test score was 41 (37-43 [21-46]). There was a significant improvement in median (IQR [range]) knowledge test score immediately post-course (43 (41-45 [33-48]); p < 0.001) which was sustained at 3-6 month follow-up (43 (41-45 [32-50]); p < 0.001 compared with baseline). Eighty-four of the 103 participants were observed in their workplace and capability, opportunity and motivation-behaviour framework was used to study the barriers and facilitators to practice change. Psychological capability and reflective motivation were the main factors enabling positive behaviour change such as team communication and pre-operative assessment, whereas physical and social opportunity accounted for the main barriers to behaviours such as performing the surgical safety checklist. Our study demonstrates that the Safe Anaesthesia from Education obstetric course is relevant in the low-resource setting and may lead to knowledge translation in clinical practice.

A Cost-Effective and Transferable Methodology for Rooftop PV Potential Assessment in Developing Countries

The efficient uptake of decentralized solar rooftop photovoltaics (PV) is in some cases hindered by ineffective energy and political framework conditions. These may be based on inaccurate and uncertain potential assessments in the early development stage of the solar market. This paper develops a more accurate, cost-effective, and robust potential assessment for emerging and developing economies. Adjusting the module efficiency corresponding to regional and household conditions improves the output accuracy. The rooftop PV market changes are simulated regarding different input changes and policy designs, including changing the Feed-In Tariff (FIT), grid tariff, and technology development. In the case study, the market potential in Vietnam is estimated at 260–280 TWh/a and is clustered into six groups in priority order, in which Hanoi and Ho Chi Minh need the most policy focus. Changing the FIT from 8.83 to 9 Euro cent/kWh and using different regional FITs can activate an additional 16% of the market and lead to a possible 28 million Euro benefit. Increasing the grid tariff to 8.7 cents/kWh could activate the self-consumption model, and the self-sufficient market can be guaranteed in the case of CAPEX and OPEX being lower than 650 Euro/kWp. Future developments of the method should focus on combining this top-down method with detailed bottom-up approaches.

What pediatric surgeons read: Utilization of APSA e-mail blast literature reviews

PURPOSE

American Pediatric Surgical Association (APSA) committees send monthly email blasts to members with links to peer-reviewed publications. This study assesses the utilization of this service.

METHODS

Email-opening and click-through rates were analyzed from 5/2012 to 4/2017 and compared to APSA and industry standards. Access was analyzed based on subject, disease type, journal, impact factor, and committee. CME questions were added in 10/2014 and emails consolidated in 1/2016. Effects of these changes were analyzed.

RESULTS

Over 60 months, 281 articles were distributed from 58 journals. Access increased significantly with impact factor (P = 0.0039). Overall email opening rate (53% ± 3%) and click-through rate (37% ± 10%) were significantly higher than all APSA emails (43%,18%, P < 0.0001) and 2017 industry standard (26%,12%,P < 0.0001). Access rates differed significantly between the twenty-five topics covered (P < 0.0001), with the highest access for appendicitis (240 ± 79, P < 0.0001). Common condition articles (157 ± 93) were accessed more than rare (55 ± 60, P < 0.0001). With email consolidation, opening rates increased (53 ± 3 to 55 ± 2, P = 0.003) and click-through rates decreased (40 ± 9 to 30 ± 8, P = 0.0002). By adding CME questions, opening rates increased nonsignificantly (52 ± 3 to 54 ± 2, P = 0.066) and click-through rate decreased significantly(41 ± 10 to 33 ± 9, P = 0.001).

CONCLUSIONS

APSA email blasts are valued by members based on high access rates. Click-through rates have declined, potentially indicating user fatigue. APSA members prefer common conditions and high impact factor journals. These data will help refine this service.

LEVEL-OF-EVIDENCE

Level III.

A Systems Dynamics Enabled Real-Time Efficiency for Fuel Cell Data-Driven Remanufacturing

Remanufacturing is a viable option to extend the useful life of an end-of-use product or its parts, ensuring sustainable competitive advantages under the current global economic climate. Challenges typical to remanufacturing still persist, despite its many benefits. According to the European Remanufacturing Network, a key challenge is the lack of accurate, timely and consistent product knowledge as highlighted in a 2015 survey of 188 European remanufacturers. With more data being produced by electric and hybrid vehicles, this adds to the information complexity challenge already experienced in remanufacturing. Therefore, it is difficult to implement real-time and accurate remanufacturing for the shop floor; there are no papers that focus on this within an electric and hybrid vehicle environment. To address this problem, this paper attempts to: (1) identify the required parameters/variables needed for fuel cell remanufacturing by means of interviews; (2) rank the variables by Pareto analysis; (3) develop a casual loop diagram for the identified parameters/variables to visualise their impact on remanufacturing; and (4) model a simple stock and flow diagram to simulate and understand data and information-driven schemes in remanufacturing.