193 research outputs found
Genetische kovarianz zwischen umnittelbarem und mĂŒtterlichem effekt je nach der richtung der innerfamilienmĂ€ssigen selektion fĂŒr das körpergewicht im alter von 2I tagen bei mĂ€usen
International audienc
Fuzzy system identification by generating and evolutionary optimizing fuzzy rule bases consisting of relevant fuzzy rules
One approach forsystem identification among many othersis the fuzzy identification approach. The advantage of this approach compared to other analytical approaches is, that it is not necessary to make an assumption for the model to be used for the identification. In addition, the fuzzy approach can handle nonlinearities easier than analytical approaches. The Fuzzy-ROSA method is a method for data-based generation of fuzzy rules. This is the first step of a two step identification process. The second step is the optimization of the remaining free parameters, i.e. the composition of the rule base and the linguistic terms, to further improve the quality of the model and obtain small interpretable rule bases. In this paper, a new evolutionary strategy for the optimization of the linguistic terms of the output variable is presented. The effectiveness of the two step fuzzy identification is demonstrated on the benchmark problem 'kin dataset' of the Delve dataset repository and the results are compared to analytical and neural network approaches
Parallel Evolutionary Algorithms for Optimizing Data{based Generated Fuzzy Systems
Abstract. In the eld of data{based fuzzy modeling, the complexity of applications and the amount of data to be processed have grown continuously. Thus, the computational eort for solving these applications has also increased drastically. In order to meet this challenge, parallel computing approaches are applied. The task here is the optimization of data{based generated fuzzy rule bases. For this kind of application the tness evaluation of an individual is very time consuming. Here, a parallel genetic algorithm is applied to solve the optimization problem in an acceptable amount of time. Furthermore, it will be analyzed how the quality of the results changes with the use of multi{population models or neighborhood models. This will be illustrated by two example applications
Novel 2-(2-arylmethylthio-4-chloro-5-methylbenzenesulfonyl)-1-(1,3,5-triazin-2-ylamino)guanidine derivatives: Inhibition of human carbonic anhydrase cytosolic isozymes I and II and the transmembrane tumor-associated isozymes IX and XII, anticancer activity, and molecular modeling studies
Managing Carbon Aspirations: The Influence of Corporate Climate Change Targets on Environmental Performance
Addressing climate change is among the most challenging ethical issues facing contemporary business and society. Unsustainable business activities are causing significant distributional and procedural injustices in areas such as public health and vulnerability to extreme weather events, primarily because of a distinction between primary emitters and those already experiencing the impacts of climate change. Business, as a significant contributor to climate change and beneficiary of externalizing environmental costs, has an obligation to address its environmental impacts. In this paper, we explore the role of firmsâ climate change targets in shaping their emissions trends in the context of a large multi-country sample of companies. We contrast two intentions for setting emissions reductions targets: symbolic attempts to manage external stakeholder perceptions via âgreenwashingâ and substantive commitments to reducing environmental impacts. We argue that the attributes of firmsâ climate change targets (their extent, form, and time horizon) are diagnostic of firmsâ underlying intentions. Consistent with our hypotheses, while we find no overall effect of setting climate change targets on emissions, we show that targets characterized by a commitment to more ambitious emissions reductions, a longer target time frame, and absolute reductions in emissions are associated with significant reductions in firmsâ emissions. Our evidence suggests the need for vigilance among policy-makers and environmental campaigners regarding the underlying intentions that accompany environmental management practices and shows that these can to some extent be diagnosed analytically
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The Role of Short-Termism and Uncertainty Avoidance in Organizational Inaction on Climate Change: A Multi-Level Framework
Despite increasing pressure to deal with climate change, firms have been slow to respond with effective action. This article presents a multi-level framework for a better understanding of why many firms are failing to reduce their absolute greenhouse gas emissions, which contribute to climate change. The concepts of short-termism and uncertainty avoidance from research in psychology, sociology, and organization theory can explain the phenomenon of organizational inaction on climate change. Antecedents related to short-termism and uncertainty avoidance reinforce one another at three levelsâindividual, organizational, and institutionalâand result in organizational inaction on climate change. The article also discusses the implications of this multi-level framework for research on corporate sustainability
Utilisation of an operative difficulty grading scale for laparoscopic cholecystectomy
Background
A reliable system for grading operative difficulty of laparoscopic cholecystectomy would standardise description of findings and reporting of outcomes. The aim of this study was to validate a difficulty grading system (Nassar scale), testing its applicability and consistency in two large prospective datasets.
Methods
Patient and disease-related variables and 30-day outcomes were identified in two prospective cholecystectomy databases: the multi-centre prospective cohort of 8820 patients from the recent CholeS Study and the single-surgeon series containing 4089 patients. Operative data and patient outcomes were correlated with Nassar operative difficultly scale, using Kendallâs tau for dichotomous variables, or JonckheereâTerpstra tests for continuous variables. A ROC curve analysis was performed, to quantify the predictive accuracy of the scale for each outcome, with continuous outcomes dichotomised, prior to analysis.
Results
A higher operative difficulty grade was consistently associated with worse outcomes for the patients in both the reference and CholeS cohorts. The median length of stay increased from 0 to 4 days, and the 30-day complication rate from 7.6 to 24.4% as the difficulty grade increased from 1 to 4/5 (both pâ<â0.001). In the CholeS cohort, a higher difficulty grade was found to be most strongly associated with conversion to open and 30-day mortality (AUROCâ=â0.903, 0.822, respectively). On multivariable analysis, the Nassar operative difficultly scale was found to be a significant independent predictor of operative duration, conversion to open surgery, 30-day complications and 30-day reintervention (all pâ<â0.001).
Conclusion
We have shown that an operative difficulty scale can standardise the description of operative findings by multiple grades of surgeons to facilitate audit, training assessment and research. It provides a tool for reporting operative findings, disease severity and technical difficulty and can be utilised in future research to reliably compare outcomes according to case mix and intra-operative difficulty
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A paradox approach to organizational tensions during the pandemic crisis
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Constructing a Distant Future: Imaginaries in Geoengineering
We develop the concept of the distant future as a new way of seeing the future in collective efforts. While a near future is represented in practical terms and concerned with forming expectations and goals under conditions of uncertainty, a distant future is represented in stylized terms and concerned with imagining possibilities under conditions of ambiguity. Management research on future-oriented action has developed around problems of the near future. To explore distant futures, we analyze the case of geoengineering, a set of planetary-scale technologies that have been proposed as solutions to the threat of climate change. Geoengineering has increasingly been treated as if it were a reality, despite continued controversy and in the absence of any implementation. We find that societal-level imaginaries that were built on deeply-held moral bases and cosmologies underpinned the conception of geoengineering, and that a dialectic process of discursive attempts to reconcile oppositional imaginaries increased the concreteness and credibility of geoengineering so that it increasingly has been treated as an âas-ifâ reality. We suggest that distant futures orient collective efforts in distinctive ways, not as concrete guides for action but by expressing critiques and alternatives, that can become treated as âas-ifâ realities
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