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101.
Neural networks are one option to implement decision support systems for health care applications. In this paper, we identify optimal settings of neural networks for medical diagnoses: The study involves the application of supervised machine learning using an artificial neural network to distinguish between gout and leukaemia patients. With the objective to improve the base accuracy (calculated from the initial set-up of the neural network model), several enhancements are analysed, such as the use of hyperbolic tangent activation function instead of the sigmoid function, the use of two hidden layers instead of one, and transforming the measurements with linear regression to obtain a smoothened data set. Another setting we study is the impact on the accuracy when using a data set of reduced size but with higher data quality. We also discuss the tradeoff between accuracy and runtime efficiency. 相似文献
102.
103.
The present study investigated the relationships between the operator's appraisal of his own work situation and the quality of his own work performance as well as self-reported errors in a nuclear power plant control room. In all, 98 control room operators from two nuclear power units filled out a questionnaire and several diaries during two operational conditions, annual outage and normal operation. As expected, the operators reported higher work demands in annual outage as compared to normal operation. In response to the increased demands, the operators reported that they used coping strategies such as increased effort, decreased aspiration level for work performance quality and increased use of delegation of tasks to others. This way of coping does not reflect less positive motivation for the work during the outage period. Instead, the operators maintain the same positive motivation for their work, and suceed in being more alert during morning and night shifts. However, the operators feel less satisfied with their work result. The operators also perceive the risk of making minor errors as increasing during outage. The decreased level of satisfaction with work result during outage is a fact despite the lowering of aspiration level for work performance quality during outage. In order to decrease relative frequencies for minor errors, special attention should be given to reduce work demands, such as time pressure and memory demands. In order to decrease misinterpretation errors special attention should be given to organizational factors such as planning and shift turnovers in addition to training. In summary, the outage period seems to be a significantly more vulnerable window in the management of a nuclear power plant than the normal power production state. Thus, an increased focus on the outage period and human factors issues, adressing the synergetic effects or work demands, organizational factors and coping resources is an important area for improvement of safety in the nuclear power industry. 相似文献
104.
105.
The influence of culture conditions on the fatty acid composition in lipids produced by Cryptococcus albidus var. albidus
CBS 4517 was studied.
The major fatty acids in C. albidus var. albidus were oleic (18:1), linoleic (18:2) and palmitic (16:0) acid. The relative
amounts of fatty acids produced varied considerably during growth and lipid accumulation phases in nitrogen-limited as well
as excess-nitrogen cultures. The degree of unsaturation correlated to the lipid content in the biomass and decreased with
increasing amounts of cellular lipid. After glucose exhaustion, no further changes in the fatty acid composition nor in the
lipid content of the cells were observed. A number of carbon and nitrogen sources could be utilized for lipid synthesis, but
they influenced the fatty acid composition only to a minor extent. 相似文献
106.
107.
Marjatta Palander Lisa Lena Opas-Hänninen Fiona Tweedie 《Computers and the Humanities》2003,37(3):359-372
The aim of this study is to show how clusteranalysis can shed light on very complexvariation in a transitional dialect zone ineastern Finland. In the course of history thisarea has been on the border between Sweden andRussia and the population has clearly been oftwo kinds: the Savo people and the Karelians.It is a well-known fact that there is variationamong these dialects, but the spread and extentof the variation has not been demonstrated previously.The idiolects of the area were studied in thelight of ten phonological and morphologicalfeatures. The material consisted of recordingsof 198 idiolects, totalling around 195 hoursand representing 19 parishes. The variation wasanalysed using hierarchical cluster analysis.While the analysis showed the extent of thevariation between idiolects and parishes, italso demonstrated how the effects of the oldparishes, borders and settlements are stillvisible in the dialects. On the parish level,the data formed clear clusters that correspondwith the main dialects in the area and itssurroundings. On the idiolect level, however,the speakers from the surrounding areas formedfairly homogenous clusters but the idiolectsfrom the Savonlinna area were spread acrossalmost all clusters. 相似文献
108.
Solveig?Lena?HansenEmail author Tim?Holetzek Clemens?Heyder Claudia?Wiesemann 《Ethik in der Medizin》2018,30(4):289-305
Definition of the problem
Concepts of stakeholder engagement are well established in business ethics and medical ethics. However, current approaches tend to see it as an end in itself. Thereby, two important aspects are often neglected: first, the general normative presuppositions of stakeholder engagement; second, moral implications concerning different modes of communication.Arguments
The present article argues that normative presuppositions of stakeholder engagement can be understood by reconstructing existing approaches. Here, three ethical theories are relevant: deontology, contractualism, and discourse ethics. Furthermore, stakeholder involvement is related to modes of communication that range from information to empowerment. Drawing upon the example of clinical research, we argue that these modes have different normative weight in relation to the respective stakeholder’s form of affectedness.Conclusion
We show why it is important for bioethics to reflect on the particular relation of affectedness and modes of participation, and how this can be realized in practice.109.
Lena Cibulski Hubert Mitterhofer Thorsten May Jörn Kohlhammer 《Computer Graphics Forum》2020,39(3):405-416
Design problems in engineering typically involve a large solution space and several potentially conflicting criteria. Selecting a compromise solution is often supported by optimization algorithms that compute hundreds of Pareto-optimal solutions, thus informing a decision by the engineer. However, the complexity of evaluating and comparing alternatives increases with the number of criteria that need to be considered at the same time. We present a design study on Pareto front visualization to support engineers in applying their expertise and subjective preferences for selection of the most-preferred solution. We provide a characterization of data and tasks from the parametric design of electric motors. The requirements identified were the basis for our development of PAVED, an interactive parallel coordinates visualization for exploration of multi-criteria alternatives. We reflect on our user-centered design process that included iterative refinement with real data in close collaboration with a domain expert as well as a summative evaluation in the field. The results suggest a high usability of our visualization as part of a real-world engineering design workflow. Our lessons learned can serve as guidance to future visualization developers targeting multi-criteria optimization problems in engineering design or alternative domains. 相似文献
110.
Spiros Mouzakitis Dimitris Papaspyros Michael Petychakis Sotiris Koussouris Anastasios Zafeiropoulos Eleni Fotopoulou Lena Farid Fabrizio Orlandi Judie Attard John Psarras 《Information Systems Frontiers》2017,19(2):321-336
Linked Data has become the current W3C recommended approach for publishing data on the World Wide Web as it is sharable, extensible, and easily re-usable. An ecosystem of linked data hubs in the Public Sector has the potential to offer significant benefits to its consumers (other public offices and ministries, as well as researchers, citizens and SMEs), such as increased accessibility and re-use value of their data through the use of web-scale identifiers and easy interlinking with datasets of other public data providers. The power and flexibility of the schema-defying Linked Data, however, is counterbalanced by inborn factors that diminish the potential for cost-effective and efficient adoption by the Public Sector. The paper analyzes these challenges in view of the current state-of-the-art in linked data technologies and proposes a technical framework that aims to hide the underlying complexity of linked data while maintaining and promoting the interlinking capabilities enabled by the Linked Data Paradigm. The paper presents the innovations behind our proposed solutions as well as their advantages, especially for the non-expert users. 相似文献