A Systematic Simulation-Based Multi-Criteria Decision-Making Approach for the Evaluation of Semi–Fully Flexible Machine System Process Parameters

Current manufacturing system health management is of prime importance due to the emergence of recent cost-effective and -efficient prognostics and diagnostics capabilities. This paper investigates the most used performance measures viz. Throughput Rate, Throughput Time, System Use, Availability, Average Stay Time, and Maximum Stay Time as alternatives that are responsible for the diagnostics of manufacturing systems during real-time disruptions. We have considered four different configurations as criteria on which to test with the proposed integrated MCDM (Multi-Criteria Decision-Making)-TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution)-based simulation approach. The main objective of this proposed model is to improve the performance of semi–fully flexible systems and to maximize the production rate by ranking the parameters from most influenced to least. In this study, first, the performance of the considered process parameters are analyzed using a simulation approach, and furthermore the obtained results are validated using real-time experimental results. Thereafter, using an Entropy method, the weights of each parameter are identified and then the MCDM-based TOPSIS is applied to rank the parameters. The results show that Throughput tTme is the most affected parameter and that Availability, average stay time, and max stay time are least affected in the case of no breakdown of machine condition. Similarly, Throughput Time is the most affected parameter and Maximum Stay Time is the least affected parameter in the case of the breakdown of machine condition. Finally, the rankings from the TOPSIS method are compared with the PROMETHEE method rankings. The results demonstrate the ability to understand system behavior in both normal and uncertain conditions.

Evaluate the results of veno-arterial extracorporeal membrane oxygenation for cardiogenic shock patient

Background: Although there are many advances in the diagnosis and resuscitation of patients with cardiogenic shock, the mortality rate is still high, especially for patients with cardiogenic shock due to complications of acute myocardial infarction, the mortality rate can be up to 50 - 70%. Objective: "Evaluate the effectiveness of clinical, subclinical and complications of V-A ECMO in patients with cardiogenic shock". Method: Retrospective analysis of patients diagnosed with cardiogenic shock supported by V-A ECMO revascularization from October 2018 and June 2020; Analyze the significance of V-A ECMO with the clinical outcome prognosis and and complications of V-A ECMO. Results: There were 23 patients hospitalized for cardiogenic shock, they have used the V-A ECMO. The mean age was 53,5±17,6, the minimum age was 13, the oldest was 76. The shortest hospital stay time was 3.5 day and the longest treatment time is 32 days. There were 15 patients alive, accounting for 65.2%, 8 patients died, accounting for 35.8%. The percentage of patients living in the group of myocarditis reached the highest rate. Common complications in patients supported by V-A ECMO are left ventricular volume overload and infection. Conclusion: V-A ECMO is a treatment option for life-threatening cardiogenic shock that has not responded to other therapies.

Uniportal Full-Endoscopic versus Minimally Invasive Decompression for Lumbar Spinal Stenosis: A Meta-analysis

Background In this study, we systematically analyze the effectiveness of the uniportal full-endoscopic (UPFE) and minimally invasive (MIS) decompression for treatment of lumbar spinal stenosis patients. Methods We performed a systematic search in Medline, Embase, Europe PMC, PubMed, Web of Science, Cochrane databases, Chinese Biomedical Literature Database, China national knowledge infrastructure, and Wanfang Data databases for all relevant studies. All statistical analyses were performed using Review Manager version 5.3. Results A total of 9 articles with 522 patients in the UPFE group and 367 patients in the MIS group were included. The results of the meta-analysis showed that the UPFE group had significantly better results in hospital stay time (mean difference [MD]: –2.05; 95% confidence interval [CI]: –2.87 to –1.23), intraoperative blood loss (MD: –36.56; 95% CI: –54.57 to –18.56), and wound-related complications (MD: –36.56; 95%CI: –54.57 to –18.56) compared with the MIS group, whereas the postoperative clinical scores (MD: –0.66; 95%CI: –1.79 to 0.47; MD: –0.75; 95%CI: –1.86 to 0.36; and MD: –4.58; 95%CI: –16.80 to 7.63), satisfaction rate (odds ratio [OR] = 1.24; 95%CI: 0.70–2.20), operation time (MD: 30.31; 95%CI: –12.55 to 73.18), complication rates for dural injury (OR = 0.60; 95%CI: 0.29–1.26), epidural hematoma (OR = 0.60; 95%CI: 0.29–1.26), and postoperative transient dysesthesia and weakness (OR = 0.73; 95%CI: 0.36–1.51) showed no significant differences between the two groups. Conclusions The UPFE decompression is associated with shorter hospital stay time and lower intraoperative blood loss and wound-related complications compared with MIS decompression for treatment of lumbar spinal stenosis patients. The postoperative clinical scores, satisfaction rate, operation time, complication rates for dural injury, epidural hematoma, and postoperative transient dysesthesia and weakness did not differ significantly between two groups.

Semantic Based Weighted Web Session Clustering Using Adapted K-Means and Hierarchical Agglomerative Algorithms

The WWW has a big number of pages and URLs that supply the user with a great amount of content. In an intensifying epoch of information, analysing users browsing behaviour is a significant affair. Web usage mining techniques are applied to the web server log to analyse the user behaviour. Identification of user sessions is one of the key and demanding tasks in the pre-processing stage of web usage mining. This paper emphasizes on two important fallouts with the approaches used in the existing session identification methods such as Time based and Referrer based sessionization. The first is dealing with comparing of current request’s referrer field with the URL of previous request. The second is dealing with session creation, new sessions are created or comes in to one session due to threshold value of page stay time and session time. So, authors developed enhanced semantic distance based session identification algorithm that tackles above mentioned issues of traditional session identification methods. The enhanced semantic based method has an accuracy of 84 percent, which is higher than the Time based and Time-Referrer based session identification approaches. The authors also used adapted K-Means and Hierarchical Agglomerative clustering algorithms to improve the prediction of user browsing patterns. Clusters were found using a weighted dissimilarity matrix, which is calculated using two key parameters: page weight and session weight. The Dunn Index and Davies-Bouldin Index are then used to evaluate the clusters. Experimental results shows that more pure and accurate session clusters are formed when adapted clustering algorithms are applied on the weighted sessions rather than the session obtained from traditional sessionization algorithms. Accuracy of the semantic session cluster is higher compared with the cluster of sessions obtained using traditional sessionization.

Initial Experience of Self-Expanding Metal Ureteral Stent in Recurrent Ureteral Stricture After Ureteroplasty

Background: The aim of this prospective study was to assess the safety and effectiveness of self-expanding metal ureteral stent (MUS) for the treatment of recurrent ureteral stricture after ureteroplasty.Methods: We prospectively included 24 patients who underwent MUS implantation between February 2019 and August 2020. The inclusion criteria for the procedure were recurrent ureteral strictures after ureteroplasty. A paired T test was used to compare continuous variables before and after surgery.Results: A total of 24 patients were finally included in this study. The stricture site was most common on the proximal ureter 19 (79.2%), followed by distal ureter 4 (16.7%) and middle ureter 1 (4.2%). The median length of ureteral stricture is 2.5 (range 1–18) cm. The median operative time was 51.5 min, and the median hospital stay time after surgery was 3 days. Post-operative complication included pain 1 (4.2%), urinary tract infection 2 (8.3%) and hematuria 2 (8.3%). After a median follow-up of 12 months, 19/24 (83.3%) patients were clinically and radiologically successful. We endoscopically adjusted or exchanged the failed stents. The volume of hydronephrosis (124.7 ± 132.5 vs. 66.4 ± 73.2 cm3, P = 0.015), blood creatinine level (104.5 ± 45.4 vs. 80.1 ± 23.2 μmol/L, P = 0.044) and urea nitrogen level (6.9 ± 2.4 vs. 4.8 ± 1.5 mmol/L, P = 0.003) decreased significantly after a median follow-up of 12 months.Conclusions: MUS is a safe and effective way to manage recurrent ureteral strictures after ureteroplasty. This technique provides a new choice for the treatment of recurrent stricture.

Comparative Efficiency of Native Insect Pollinators in Reproductive Performance of Medicago sativa L. in Pakistan

Lucerne (Medicago sativa L.) is a cross-pollinated crop and requires entomophilous pollination for tripping of flowers and subsequent pod and seed set. To discover the best pollinators for lucerne seed production, a two-year field trial was carried out at the research farm of MNS University of Agriculture, Multan, Pakistan. Abundance and diversity of insect pollinators along with the foraging behavior were recorded in terms of tripping efficiency, stay time, visitation rate and pollen harvest. The single-visit efficiency of abundant insect pollinators was also evaluated in terms of number of seeds and seed weight per raceme along with germination percentage. Ten most abundant floral visitors (five solitary bee species, three honeybee species and two syrphid fly species) were tested for their pollination efficiency. Honeybees were most abundant in both the years followed by the solitary bees and syrphid flies. Single-visit efficacy in terms of number of pods of raceme, number of seeds per raceme, 1000 seed weight and germination percentage revealed Megachile cephalotes as the most efficient insect pollinator followed by Megachile hera and Amigella sp. Future studies should investigate the biology and ecology of these bee species with special emphasis on their nesting behavior and seasonality.

Does Exposure to Animal Cognition Research Influence the Zoo Visitor Experience?

Zoos average about 183 million visitors per year, which makes them a major source for educating the public due to the diverse and wide-ranging demographic that visit. Zoos are increasingly a source of scientific research in a variety of subfields, including animal cognition, although much of this research takes place behind the scenes. Bringing this research to the public perspective has the potential to increase engagement of zoo visitors. However, it is not always possible to show live research, but videos have been found to be an effective educational approach in other domains. Here, we presented a brief video illustrating cognitive research involving sun bears at Zoo Atlanta to determine the potential effect on visitors. We measured several aspects of visitor behavior (stay time and actual behaviors in the exhibit), attitudes (towards both animal research and educational technology), and knowledge gained at the exhibit. We also presented a control video that focused on sun bear enrichment to tease out whether potential effects on visitors were related to the research focus of the video, or merely an effect of a video playing in the exhibit space. Visitor behavior, attitudes, and knowledge were determined by observing a randomly selected visitor’s behavior throughout their time in the exhibit space, and then requesting completion of a survey when they exited the exhibit (N = 148). We compared various aspects of behavior, attitudes, and knowledge across the Scientific Video, Enrichment Video, and No Video conditions. There were no differences between the Scientific Video and the Enrichment Video conditions; however, some differences were found between visitors who experienced a video during their visit (scientific or enrichment video) versus those who did not. Attitudes towards technology in the exhibit space were generally positive. There was also a significant correlation between visitor stay time (overall time spent in the exhibit space) and knowledge gained. Visitors learning about research in zoos remains important, but it is unclear if a video is a sufficient means to share that information.

Initial stay times for uncompensable occupational heat stress in young and older men: a preliminary assessment

During uncompensable occupational heat stress, heat-mitigation controls are required to prevent core temperature exceeding recommended limits (≥38°C). However, the initial stay time before employing controls remained unknown. We estimated these times for moderate-intensity work at 26, 28, 30, and 32°C wet-bulb globe temperatures (WBGT) in 50 young (18-30 years) and older (50-70 years), non-heat acclimatized men. Initial stay time was 111 min at 26°C WBGT and declined exponentially to 44 min at 32°C WBGT. Novelty point • We provide estimates of the moderate-intensity work duration before heat-mitigation is required in wet-bulb globe temperatures between 26-32°C for young and older, non-heat acclimatized men.

Using Mobile Phone Data to Understand the Demographic Characteristics and Behavioral Patterns of Park Visitors in a Megacity, Beijing, China

BackgroundUrban parks are important places that allow urban residents to experience nature but are also associated with the risk of exposure to contaminated soil. Local researches on demographic characteristics and population behavior patterns are the basis of soil exposure assessment. The objectives were to determine park visitors’ demographic characteristics and behavioral patterns. MethodsA total of 86 urban parks in Beijing were selected, and mobile phone data were used to quantify the park visits, identify the demographic characteristics of the visitors, and determine the visitors’ stay times. A Kruskal-Wallis test and kernel density estimation were used for difference analysis and to describe the spatial aggregation of visitors, respectively. A random forest model was used to analyze the factors influencing the visitors’ stay times.ResultsVisitor numbers at comprehensive parks and theme parks decreased significantly in winter, whereas seasonal variations in visitor numbers at community parks and country parks were small. Almost half of the visitors to Beijing’s urban parks were foreign visitors, who, unlike local visitors, preferred to visit parks located in the city’s center. Parks were mostly used by males and visitors aged 31–45. Most visitors stayed in the park for 1–2 h, and the distance from a given visitor’s home to the park was the most important factor affecting stay time, contributing 80.65% of the difference in stay time.ConclusionsThis study provides a quantitative analysis of the patterns relating to urban park use by different groups of people. Changes in behavior patterns of different groups of people should be considered when assessing soil exposure.