Structural Dynamic Modeling and Simulation of Acoustic Sound Emissions of Electric Traction Motors

The acoustic behavior of electric drive systems is one of the main comfort criteria of electromobility. Due to its high-pitched sound emissions, the electric motor plays an important role. The corresponding noise is predominantly determined by the vibrational behavior of the electric machine given by the structural transfer function. The early phase consideration of the vibrational behavior of electric machine structures becomes even more relevant if one takes into account the strong requirements towards lightweight design and spatial restrictions inside vehicle applications. One of the most important tools inside the early stage development is the structural dynamic simulation. In order to be able to sustainably predict the vibrational behavior of an electric machine, the corresponding simulation model needs to sufficiently represents all acoustically relevant structural effects and at the same time remain practical and numerically solvable in a reasonable amount of time. This conflict is dealt with in this dissertation. The acoustic behavior of electric machines is strongly coupled to the vibrational behavior of the electric machine stator. The microscopic representation of the strongly heterogeneous stator structure is elaborate and requires a large computational effort. Therefore, so-called homogenized substitutional materials are typically employed in structural dynamical simulations of electric motors. The homogenized materials intend to represent the effective stiffness and damping properties of the underlying heterogeneous structure by an anisotropic substitutional material. Typically, the corresponding effective stiffness and damping properties of the homogeneous material are reversely obtained from experimental investigations on the particular structure. However, this approach presumes the physical existence of prototypes that can be tested. In this thesis, different so-called homogenization techniques will be investigated that allow the identification of homogenized material properties based micromechanical models of the underlying heterogeneous structure. Therefore, various numerical and analytic approaches will be investigated. The resulting modeling approaches will be validated based on different experimental analyses on an exemplary stator structure and subsequently be employed in a comprehensive acoustic simulation of an entire electric drive train. However, the simulation and optimization of the mostly broadband acoustic behavior of electric motors remains time-consuming. In order to efficiently predict the acoustic behavior of electric machines the use of model order reduction methods can be advantageous. Model order reduction methods typically involve mathematical algorithms that yield the effective reduction of the model’s degrees-of-freedom. In this thesis, different model order reduction techniques will be applied and evaluated regarding their usability in the area of vibrational simulations of electric machines. A particularly efficient model order reduction could be achieved by using so-called Krylovsubspaces. By employing the Krylov-subspace method the solution time for particular operation points of the electric machine could be reduced to less than 10% of the original solution time. The integrated modeling procedure, presented in this thesis, yields the sustainable and efficient representation of the vibrational behavior of electric machines. It allows the early phase evaluation and optimization of the acoustic behavior of different electric machine designs. This thesis differs from similar research so far that a generic approach was used to make the representation of the global dynamic behavior of the electric machine possible. The process includes micromechanical models which add a unique robustness and sustainability to the approach

past behavior moderates the prediction of adherence

Background: Vaccination effectively prevents seasonal influenza. To promote vaccination adherence, it is necessary to understand the motivational process that underlies vaccination behavior. This was examined along with the moderating influence of past behavior on intention formation. Methods: German employees (N = 594) completed questionnaires at baseline and at 7-month followup. Regression analyses were conducted for mediation and moderated mediation. Results: Intention at Time 1 mediated the effect of risk perception, and positive and negative outcome expectancies on Time 2 vaccination. Past behavior moderated this effect: there was a mediation effect for risk perception and outcome expectancies only for those individuals who did not participate annually. Conclusions: Risk perception and outcome expectancies influenced intentions to receive vaccination, which in turn predicted participation. Hence, these social-cognitive variables could be targeted in vaccination campaigns to increase intentions. However, vaccination experience affected the formation of intentions and should be accounted for when developing interventions

Who Participates in Seasonal Influenza Vaccination? Past Behavior Moderates the Prediction of Adherence

Background. Vaccination effectively prevents seasonal influenza. To promote vaccination adherence, it is necessary to understand the motivational process that underlies vaccination behavior. This was examined along with the moderating influence of past behavior on intention formation. Methods. German employees (N = 594) completed questionnaires at baseline and at 7-month followup. Regression analyses were conducted for mediation and moderated mediation. Results. Intention at Time 1 mediated the effect of risk perception, and positive and negative outcome expectancies on Time 2 vaccination. Past behavior moderated this effect: there was a mediation effect for risk perception and outcome expectancies only for those individuals who did not participate annually. Conclusions. Risk perception and outcome expectancies influenced intentions to receive vaccination, which in turn predicted participation. Hence, these social-cognitive variables could be targeted in vaccination campaigns to increase intentions. However, vaccination experience affected the formation of intentions and should be accounted for when developing interventions

The production of less harmful and less toxic sparklers in an experiment for school students

In this article, a new and simple way of producing sparklers is presented as a school experiment. These sparklers are more environmentally friendly and less health threatening than sparklers produced with existing preparation methods. The problem of conventional sparklers is the toxicity of barium nitrate, which is used as the oxidizer. The substitution of this oxidizer with strontium nitrate and also the reduction of the weight proportion makes the new mixture less dangerous and less toxic. Various tests for the categorization of high-energetic materials show that the newly developed sparklers are not classified as explosives. Furthermore, the tests demonstrate that the newly developed sparklers are not as dangerous as commercial sparklers. Due to their lower health risk, these new sparklers are well suited for use in school education. In addition, expenditure for this experiment is low and integrating it into the upper secondary level curriculum is easy. Sparklers are an impressive example of redox reactions from everyday life. The experiment is a best-practice application for chemistry education, incorporating current results of chemistry research

Effects of Stocking Rate and Environmental Enrichment on the Ontogeny of Pecking Behavior of Laying Hen Pullets Confined in Aviary Compartments during the First 4 Weeks of Life

Simple Summary The objective of this study was to describe the development of aggressive pecking, gentle feather pecking and severe feather pecking of non-beak-trimmed laying hen pullets during the first 4 weeks of life. The pecking behavior patterns were observed in three different experimental groups, which differed in stocking rates and the provision of enrichment material. The enrichment materials were suitable and intensely used by the pullets. The provision of pecking blocks and pecking stones is recommended as a preventive measure from the first day of life onwards for pullets housed in commercial rearing aviaries. There was no effect of reduced stocking rate, most likely due to the low variation in stocking rates. The objective of this study was to describe the ontogeny of the severe feather pecking (SFP), gentle feather pecking (GFP), aggressive pecking (AP), and enrichment pecking (EP) of non-beak-trimmed Lohmann Brown (LB)-pullets during the first 4 weeks of life (observation on 1st, 8th, 15th, 22nd, and 29th days of life) while they were kept within the compartments of a commercial rearing aviary (without access to a litter area). All chicks were placed into compartments of the middle tier of the aviary on the 1st day of life. On the 10th day of life, half of the chicks of each compartment were moved into the compartments of the lower tier. The aviary floor was covered with chick paper before the placement of the chicks and fully or partially removed from the 15th day of life onwards. The pecking behavior patterns were observed in three experimental groups (EG): NE (not enriched): group size until/after 10th day of life: 230/115;120.8/60.4 birds/m(2), no enrichment;EL (enriched, low stocking rate): group size until/after 10th day of life: 203/101, 106.6/53.6 birds/m(2);and EH (enriched, high stocking rate): group size until/after 10th day of life: 230/115;120.8/60.4 birds/m(2), both pecking stones and blocks as enrichment) in two rearing periods. For each pecking behavior pattern, an independent regression model with the parameters EG, chick paper, observation day, and functional area was estimated. GFP, SFP, and EP increased with age during the observation. The AP rate was highest in all EGs on the first day of life and decreased during the observation period. A pairwise comparison of NE (high stocking rate without enrichment) with EH (high stocking rate with enrichment and with EL (low stocking rate with enrichment) showed a significant effect of the EG on pecking behavior, with more SFP, AP, and GFP in NE. There were no differences between EL and EH, indicating that the provision of pecking materials had more influence than the stocking rate. However, we presumed that the difference between the stocking rates were too small to observe an effect. AP, SFP, and GFP were significantly higher on wired slats, as compared to the perches and the vicinity of the enrichment materials. The enrichment materials were suitable and intensely used by the pullets. The provision of pecking blocks and pecking stones was recommended as a preventive measure from the first day of life onwards for pullets housed in commercial rearing aviaries. There was no effect of reduced stocking rate, most likely due to the low variation in stocking rates

Scientometric Analysis and Density-Equalizing Mapping

Pulmonary hypertension (PH) is characterized by the increase of the mean pulmonary arterial pressure in the lung circulation. Despite the large number of experimental and clinical studies conducted on pulmonary hypertension, there is no comprehensive work that analyzed the global research activity on PH so far. We retrieved the bibliometric data of the publications on pulmonary hypertension for two periods from the Web of science database. Here, we set the first investigation period from 1900 to 2007 (t1) due to the cited half life of articles and the relating difficulties to interpret the citation parameters. The second evaluation period (t2) covers the time interval from 2008 onwards including the year 2015. The data were analyzed and processed to density-equalizing maps using the NewQIS platform. A total number of 18,986 publications were identified in t1 that come from 85 countries. The US published the highest number of publications (n = 7,290), followed by the UK, Germany, Japan and France. In t2 19,676 items could be found worked out by 130 countries. The raking started just the same with the USA as most publishing nation with 7,127 publications on PH, followed by the UK and Germany. Japan fell back on 6th place, whereas China came into view on the 5th position. Analyzing the average citation rate as a parameter for research quality, Mexico reached the highest value in t1 and Ireland in t2. While, the country specific h-index underlined the leading position of the US research in both evaluation periods again. The average number of international collaboration items was expanding from none in 1978 to 530 items in 2015 with the USA as the country with the highest number of collaboration articles. The present study is the first large scale density-equalizing mapping and scientometric analysis of global PH research activity. Our data draw a sketch of the global research architecture in this field, indicating a need for specific research programs in countries with a lower human development index

The IGF-1R Inhibitor NVP-AEW541 Causes Insulin-Independent and Reversible Cardiac Contractile Dysfunction

The antitumor treatment NVP-AEW541 blocks IGF-1R. IGF-1R signaling is crucial for cardiac function, but the cardiac effects of NVP-AEW541 are ill defined. We assessed NVP-AEW541′s effects on cardiac function and insulin response in vivo and in isolated working hearts. We performed a dose–response analysis of NVP-AEW541 in male, 3-week-old rats and assessed the chronic effects of the clinically relevant dose in adult rats. We performed glucose tolerance tests and echocardiography; assessed the expression and phosphorylation of InsR/IGF-1R and Akt in vivo; and measured substrate oxidation, contractile function, and insulin response in the isolated working hearts. NVP-AEW541 caused dose-dependent growth retardation and impaired glucose tolerance in the juvenile rats. In the adults, NVP-AEW541 caused a continuously worsening depression of cardiac contractility, which recovered within 2 weeks after cessation. Cardiac Akt protein and phosphorylation were unchanged and associated with InsR upregulation. An acute application of NVP-AEW541 in the working hearts did not affect cardiac power but eliminated insulin’s effects on glucose and fatty acid oxidation. The systemic administration of NVP-AEW541 caused dose- and time-dependent impairment of glucose tolerance, growth, and cardiac function. Because cardiac insulin signaling was maintained in vivo but absent in vitro and because contractile function was not affected in vitro, a direct link between insulin resistance and contractile dysfunction appears unlikely

Combination of Digital and Conventional Workflows in the CAD/CAM-Fabrication of an Implant-Supported Overdenture

Completely digital workflows for the fabrication of implant-supported removable restorations are not yet common in clinical dental practice. The aim of the current case report is to illustrate a reliable and comfortable workflow that reasonably merges conventional and digital workflows for the CAD/CAM-fabrication of implant-supported overdentures. The 53-year old patient was supplied with a digitally processed complete denture in the upper jaw and, simultaneously, with an overdenture supported by four interforaminal implants in the lower jaw. The overdenture included a completely digitally processed and manufactured alloy framework that had been fabricated by selective laser sintering. The case report indicates that digital manufacturing processes for extensive and complex removable restorations are possible. However, as it is currently not yet possible to digitally obtain functional impressions, future developments and innovations might focus on that issue

Improving the proteome coverage of Daphnia magna - implications for future ecotoxicoproteomics studies

Aquatic pollution is an increasing problem and requires extensive research efforts to understand associated consequences and to find suitable solutions. The crustacean Daphnia is a keystone species in lacustrine ecosystems by connecting primary producers with higher trophic levels. Therefore, Daphnia is perfectly suitable to investigate biological effects of freshwater pollution and is frequently used as an important model organism in ecotoxicology. The field of ecotoxicoproteomics has become increasingly prevalent, as proteins are important for an organism's physiology and respond rapidly to changing environmental conditions. However, one obstacle in proteome analysis of Daphnia is highly abundant proteins like vitellogenin, decreasing the analytical depth of proteome analysis. To improve proteome coverage in Daphnia, we established an easy-to-use procedure based on the LC-MS/MS of whole daphnids and the dissected Daphnia gut, which is the main tissue getting in contact with soluble and particulate pollutants, separately. Using a comprehensive spectral library, generated by gas-phase fractionation and a data-independent acquisition method, we identified 4621 and 5233 protein groups at high confidence (false discovery rate < 0.01) in Daphnia and Daphnia gut samples, respectively. By combining both datasets, a proteome coverage of 6027 proteins was achieved, demonstrating the effectiveness of our approach