performance reduction
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2021 ◽  
Vol 13 (22) ◽  
pp. 12647
Author(s):  
Julian Amon ◽  
Margarethe Rammerstorfer ◽  
Karl Weinmayer

Environmental portfolios via screening or optimization with respect to ecological criteria are not clear-cut concepts. Often, they urge investors to reduce the asset universe, which is accompanied by diversification losses. In this article, we show that a simple passive asset selection strategy based on environmental criteria allows ecological investors to adjust their portfolios without compromising or even reducing risk-adjusted financial performance. In detail, we show that screening does not lead to a significant financial performance reduction. Moreover, we propose an asset selection based on an environmental criteria that improves the portfolios’ financial performance, and further improves its potential positive environmental impact. Our results suggest that a combination of a screening and an environmental-scoring-based asset allocation seems to be a viable option for environmentally responsible investors leveraging the advantages of both strategies. Furthermore, we construct a risk factor CMP (clean minus polluting) and document a significant factor loading when added to the Fama–French five-factor model, suggesting the existence of a risk premium based on a firm’s environmental performance.


Author(s):  
Mauricio A. Ramírez-Moreno ◽  
Patricio Carrillo-Tijerina ◽  
Milton Osiel Candela-Leal ◽  
Myriam Alanis-Espinosa ◽  
Juan Carlos Tudón-Martínez ◽  
...  

Non-pathological mental fatigue is a recurring, but undesirable condition among people in the fields of office work, industry, and education. This type of mental fatigue can often lead to negative outcomes, such as performance reduction and cognitive impairment in education; loss of focus and burnout syndrome in office work; and accidents leading to injuries or death in the transportation and manufacturing industries. Reliable mental fatigue assessment tools are promising in the improvement of performance, mental health and safety of students and workers, and at the same time, in the reduction of risks, accidents and the associated economic loss (e.g., medical fees and equipment reparations). The analysis of biometric (brain, cardiac, skin conductance) signals has proven to be effective in discerning different stages of mental fatigue; however, many of the reported studies in the literature involve the use of long fatigue-inducing tests and subject-specific models in their methodologies. Recent trends in the modeling of mental fatigue suggest the usage of non subject-specific (general) classifiers and a time reduction of calibration procedures and experimental setups. In this study, the evaluation of a fast and short-calibration mental fatigue assessment tool based on biometric signals and inter-subject modeling, using multiple linear regression, is presented. The proposed tool does not require fatigue-inducing tests, which allows fast setup and implementation. Electroencephalography, photopletismography, electrodermal activity, and skin temperature from 17 subjects were recorded, using an OpenBCI helmet and an Empatica E4 wristband. Correlations to self-reported mental fatigue levels (using the fatigue assessment scale) were calculated to find the best mental fatigue predictors. Three-class mental fatigue models were evaluated, and the best model obtained an accuracy of 88% using three features, β/θ (C3), and the α/θ (O2 and C3) ratios, from one minute of electroencephalography measurements. The results from this pilot study show the feasibility and potential of short-calibration procedures and inter-subject classifiers in mental fatigue modeling, and will contribute to the use of wearable devices for the development of tools oriented to the well-being of workers and students, and also in daily living activities.


Coatings ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1361
Author(s):  
István Bodnár ◽  
Dávid Matusz-Kalász ◽  
Rafael Ruben Boros ◽  
Róbert Lipták

The Hungarian society and the Hungarian state are constantly increasing their solar capacity. More and more solar power plants are being put into operation. The largest of these has a 100 MW peak capacity. Such power plants do not require constant maintenance. However, in the case of low productivity, a conditional assessment is required. The reason for production loss can also be manufacturing, installation, and operational errors. A flying drone was used for finding failures by thermographic scouting. Furthermore, electroluminescent (EL) and flash tests give a comprehensive view of the real state of the modules in a mobile laboratory. We had the opportunity to summarize these test results of more than a thousand modules operating in a solar power plant. The report on the power plant shows that a significant part of the modules became unusable in a short time. After four years, 10% of the 260 Wp modules suffered a performance reduction of more than 10%.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jeroen Bleker ◽  
Derya Yakar ◽  
Bram van Noort ◽  
Dennis Rouw ◽  
Igle Jan de Jong ◽  
...  

Abstract Objectives To investigate a previously developed radiomics-based biparametric magnetic resonance imaging (bpMRI) approach for discrimination of clinically significant peripheral zone prostate cancer (PZ csPCa) using multi-center, multi-vendor (McMv) and single-center, single-vendor (ScSv) datasets. Methods This study’s starting point was a previously developed ScSv algorithm for PZ csPCa whose performance was demonstrated in a single-center dataset. A McMv dataset was collected, and 262 PZ PCa lesions (9 centers, 2 vendors) were selected to identically develop a multi-center algorithm. The single-center algorithm was then applied to the multi-center dataset (single–multi-validation), and the McMv algorithm was applied to both the multi-center dataset (multi–multi-validation) and the previously used single-center dataset (multi–single-validation). The areas under the curve (AUCs) of the validations were compared using bootstrapping. Results Previously the single–single validation achieved an AUC of 0.82 (95% CI 0.71–0.92), a significant performance reduction of 27.2% compared to the single–multi-validation AUC of 0.59 (95% CI 0.51–0.68). The new multi-center model achieved a multi–multi-validation AUC of 0.75 (95% CI 0.64–0.84). Compared to the multi–single-validation AUC of 0.66 (95% CI 0.56–0.75), the performance did not decrease significantly (p value: 0.114). Bootstrapped comparison showed similar single-center performances and a significantly different multi-center performance (p values: 0.03, 0.012). Conclusions A single-center trained radiomics-based bpMRI model does not generalize to multi-center data. Multi-center trained radiomics-based bpMRI models do generalize, have equal single-center performance and perform better on multi-center data.


Author(s):  
Christophe Lambert ◽  
Ramona Ritzmann ◽  
Ralph Akoto ◽  
Maxime Lambert ◽  
Thomas Pfeiffer ◽  
...  

AbstractInjuries effect the performance of athletes. Severity of injuries is determined by time loss and sporting performance reduction. To treat injuries adequately, it is necessary to get an overview of varied injuries types in different sports disciplines. In a retrospective study 7.809 athletes from Germany, Switzerland and Austria competing in competitive or recreational levels of sports were included. Injury prevalence was highest in team sports (75%), followed by combat (64%), racquet (54%) and track and field (51%). Knee (28%) and shoulder (14%) were the most at risk joints. Time loss in sporting activity after injury was longest in the region of knee (26 weeks). Of all reported injuries, 48% were accompanied by a reduced level of performance. The highest injury prevalence occurred in the year 2016 (45%). More injuries occurred during training (58%) compared to competition (42%). Across Olympic disciplines, a large number of injuries occurred during training sessions. Injury frequency increased as the Olympic games drew closer. Knee and shoulder injuries were the most severe injuries with respect to time loss and reduction sporting performance.


2021 ◽  
Vol 15 (03) ◽  
Author(s):  
Mohd N. Nawi ◽  
Dilla D. Berhanuddin ◽  
Mohd A. Mahdi ◽  
Burhanuddin Y. Majlis ◽  
Richard M. De La Rue ◽  
...  

2021 ◽  
Author(s):  
Andrew Fisher ◽  
Jiten Kaura ◽  
Matthew Kratzer ◽  
Ken Oyler ◽  
Ron Reutzel ◽  
...  

Abstract The deepwater development field in the western Gulf of Mexico (GoM) presents an array of complex challenges for ultra-deepwater drilling operations. The four well campaign was particularly challenging due to extreme water depths, remote location, well trajectory and a narrow pressure environment, 350-100 kpa (50-150 psi), for extended reservoir laterals. The authors highlight the use of innovative technology employed to drill and complete wells in the western GoM deployment, coupled with the first-ever use of controlled mud level (CML), managed pressure drilling technology in the Gulf of Mexico. The approach of selecting the fluid systems to achieve the objectives and the use of hydraulics modeling software with CML modeling capability in the design, planning and execution phases of the project allowed for fluid design optimization. The results were a successful drilling and completion campaign managing multiple fluids systems and operations on an ultra-deepwater, dual-activity drill ship in water depths more than 8,500 ft (2,591 m). The authors discuss the initial use of a low equivalent circulating density (ECD), flat-rheology synthetic based fluid (SBF) designed for narrow margin drilling applications and the transition to the deployment of a newly developed high-performance water-based mud (HPWBM) optimizing the operations to drill the intermediate intervals for final two wells. The authors also will discuss use of the reservoir drill-in fluid (RDF) and solids-free screen running fluids (SF-SRF), designed specifically for use in these open holes, gravel pack completions at hole angles upwards of 90°. Operational efficiencies derived from use of these fluids include ECD management, hole cleaning, directional performance, reduction in downhole losses, and the elimination of non-productive time (NPT) in a narrow margin environment with no loss of rate of penetration (ROP). Additional efficiencies include the seamless transition from derived from use of water-based fluids for drilling and completion phases. Use of the CML technology allowed for precise control of the hydrostatic pressure on wells that previously would not have been technically feasible to drill or complete. The novel use of the newly developed HPWBM on this campaign enabled reduced health, safety and environmental (HSE) exposure impact, increased tank and rig cleaning efficiency, and the elimination of a wellbore cleanout run since the entire well was drilled with only water-based fluids. The fluids were successfully employed in the four wells drilled and completed in a managed pressure environment utilizing CML technology.


2021 ◽  
Vol 12 ◽  
Author(s):  
Yanyan Wu ◽  
Lili Wang ◽  
Ruiqing Luo ◽  
Hongli Chen ◽  
Cunxi Nie ◽  
...  

The effects of different doses of a multispecies probiotic (MSP) mixture on growth performance, the incidence of diarrhea rate and immune function, and fecal microbial diversity and structure were evaluated in pre-weaning Holstein dairy calves at WK2, WK4, WK6, and WK8. Forty Chinese Holstein female newborn calves were randomly assigned to four treatments with 10 calves in each group, C (control group), T1 (0.5 g MSP/calf/day, T2 (1 g MSP/calf/day), and T3 (2 g MSP/calf/day) groups. The experimental period was 56 days. Feed intake and health scoring were recorded every day until the end of the experiment. Fecal contents and blood samples were sampled at WK2, WK4, WK6, and WK8. Growth performance, incidence of diarrhea, and total serum concentrations (IgA, IgG, and IgM) were analyzed. Bacterial 16S rRNA and fungal ITS genes were high-throughput sequenced for fecal microbiota. The relationships among the populations of the principal fecal microbiota at WK2 and the growth performance or serum immunoglobulin concentrations were analyzed using Pearson’s rank correlation coefficients. The MSP supplementation reduced the incidence of diarrhea in the first 4 weeks of life, and serum IgA, IgG, and IgM concentrations increased between WK2 and WK8 in the T3 group. There was an increase in growth performance and reduction in the incidence of diarrhea until WK4 after birth in T3 group, compared with the control, T1, and T2 groups. The results of fecal microbiota analysis showed that Firmicutes and Bacteroides were the predominant phyla, with Blautia, Ruminococcaceae_UCG-005, norank_f__Muribaculaceae, Bacteroides, Subdoligranulum, and Bifidobacterium being the dominant genera in calf feces. Aspergillus, Thermomyces, and Saccharomyces were the predominant fungal phyla. Compared with the control, in T1 and T2 groups, the MSP supplementation reduced the relative abundance of Bacteroidetes and increased the relative abundance of Bifidobacterium, Lactobacillus, Collinsella, and Saccharomyces at WK2 in group T3. Thus, the fecal microbial composition and diversity was significantly affected by the MSP mixture during the first 2 weeks of the calves’ life. MSP mixtures reduced the incidence of diarrhea in pre-weaning calves (during the first 4 weeks of life). There was a significant improvement in growth performance, reduction in calf diarrhea, balance in the fecal microbiota, and an overall improvement in serum immunity, compared with the control group. We, therefore, recommend adding 2 g/day of multispecies probiotic mixture supplementation in diets of dairy calves during their first 4 weeks of life before weaning.


2021 ◽  
Vol 14 (7) ◽  
pp. 96-101
Author(s):  
Leidiane Lourenço Rodrigues ◽  
Rafaela Martins Santos

The relationship between the vegetarian diet and sports performance is very much investigated since there are many doubts about its results, justified by the main protein source of the diet being of vegetable origin, which, consequently, raises more attention on the levels of some vitamins and minerals, immune function, hormonal relationships and even on the nutritional needs for athletes. Immune functions are also very much emphasized, because they may present small alterations related to prolonged overtraining, causing chronic performance reduction. However, vegetarian diets associated with moderate and regulating workouts have a positive result. Vegetarians have a low level of creatine in their bodies, because this amino acid is more present in animal foods. This may affect a higher performance in supra-maximal workouts; however, a good creatine supplementation is a good alternative. Thus, this study aimed to To understand the effectiveness of vegetarian diet associated with sport performance. This work was an exploratory literature review, with a qualitative approach. Several articles were investigated from 2002 to 2018, in Scielo and Medline databases. However, it was possible to review that the aerobic capacity of vegetarian and omnivorous athletes did not present differences, and with the monitoring of routine tests and a good professional nutritionist, these results can be very well controlled.


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