Influence of the Rivet Coating on the Friction during Self-Piercing Riveting

2021 ◽  
Vol 883 ◽  
pp. 11-18
Author(s):  
Benedikt Uhe ◽  
Clara Maria Kuball ◽  
Marion Merklein ◽  
Gerson Meschut

The number of multi-material joints is increasing as a result of lightweight design. Self-piercing riveting (SPR) is an important mechanical joining technique for multi-material structures. Rivets for SPR are coated to prevent corrosion, but this coating also influences the friction that prevails during the joining process. The aim of the present investigation is to evaluate this influence. The investigation focuses on the common rivet coatings Almac® and zinc-nickel with topcoat as well as on uncoated rivet surfaces. First of all, the coating thickness and the uniformity of the coating distribution are analysed. Friction tests facilitate the classification of the surface properties. The influence of the friction on the characteristic joint parameters and the force-stroke curves is analysed by means of experimental joining tests. More in-depth knowledge of the effects that occur is achieved through the use of numerical simulation. Overall, it is shown that the surface condition of the rivet has an impact on the friction during the joining process and on the resulting joint. However, the detected deviations between different surface conditions do not restrict the operational capability of SPR and the properties of uncoated rivet surfaces, in particular, are similar to those of Almac®-coated rivets. It can thus be assumed that SPR with respect to the joining process is also possible without rivet coating in principle.

2020 ◽  
Vol 3 (152) ◽  
pp. 92-99
Author(s):  
S. M. Geiko ◽  
◽  
O. D. Lauta

The article provides a philosophical analysis of the tropological theory of the history of H. White. The researcher claims that history is a specific kind of literature, and the historical works is the connection of a certain set of research and narrative operations. The first type of operation answers the question of why the event happened this way and not the other. The second operation is the social description, the narrative of events, the intellectual act of organizing the actual material. According to H. White, this is where the set of ideas and preferences of the researcher begin to work, mainly of a literary and historical nature. Explanations are the main mechanism that becomes the common thread of the narrative. The are implemented through using plot (romantic, satire, comic and tragic) and trope systems – the main stylistic forms of text organization (metaphor, metonymy, synecdoche, irony). The latter decisively influenced for result of the work historians. Historiographical style follows the tropological model, the selection of which is determined by the historian’s individual language practice. When the choice is made, the imagination is ready to create a narrative. Therefore, the historical understanding, according to H. White, can only be tropological. H. White proposes a new methodology for historical research. During the discourse, adequate speech is created to analyze historical phenomena, which the philosopher defines as prefigurative tropological movement. This is how history is revealed through the art of anthropology. Thus, H. White’s tropical history theory offers modern science f meaningful and metatheoretically significant. The structure of concepts on which the classification of historiographical styles can be based and the predictive function of philosophy regarding historical knowledge can be refined.


2021 ◽  
Vol 8 (1) ◽  
pp. 144-155 ◽  
Author(s):  
Gizem Çakın ◽  
Ignatius Darma Juwono ◽  
Marc N. Potenza ◽  
Attila Szabo

Abstract Background and aims Exercise addiction may be conceptualized as a behavioral addiction in which a person develops an unhealthy obsession with exercise and physical activity. While exercise addiction is not a formally recognized disorder in the Diagnostic and Statistical Manual or the International Classification of Diseases, it has been studied and connected to both personal and situational factors. Perfectionism is a feature that has been strongly linked to exercise addiction. The objective of this systematic literature review, performed by following the PRISMA protocol, was to examine relationships between exercise addiction and perfectionism while also considering the subdimensions of perfectionism in different groups. Methods Three databases (PsycINFO, PubMed/Medline, and SPORTDiscus) were examined. Sixty relevant articles were identified, of which 22 met inclusion criteria. Results The findings substantiate that perfectionism and its dimensions are weakly or moderately related to exercise addiction. This relationship has been observed in adults, adolescents, athletes, and patients with eating disorders. Of the 22 studies examined, only one did not identify an association between perfectionism or its subdomain(s) and exercise addiction. However, in most studies, the common variance between perfectionism and exercise addiction is relatively small, raising questions regarding the clinical relevance of the relationship. Conclusion Perfectionism is related to exercise addiction, but the strength of the relationship varies in different circumstances, which should be examined in future research.


Legal Studies ◽  
2001 ◽  
Vol 21 (2) ◽  
pp. 153-191 ◽  
Author(s):  
Joachim Dietrich

The common law has solved questions of liability arising in the context of precontractual negotiations by resort to a range of different doctrines and approaches, adopting in effect ‘piecemeal’ solutions to questions of precontractual liability. Consequently, debate has arisen as to how best to classify or categorise claims for precontractual work and as to which doctrines are best suited to solving problems arising from anticipated contracts. The purpose of this article is to consider this question of how best to classify (cases of) precontractual liability. The initial focus will be on the ongoing debate as to whether principles of contract law or principles of unjust enrichment can better solve problems of precontractual liability. I will be suggesting that unjust enrichment theory offers little by way of explanation of cases of precontractual liability and, indeed, draws on principles of contract law in determining questions of liability for precontractual services rendered, though it does so by formulating those principles under different guises. Irrespective, however, of the doctrines utilised by the common law to impose liability, it is possible to identify a number of common elements unifying all cases of precontractual liability. In identifying such common elements of liability, it is necessary to draw on principles of both contract and tort law. How, then, should cases of precontractual liability best be classified? A consideration of the issue of classification of precontractual liability from a perspective of German civil law will demonstrate that a better understanding of cases of precontractual liability will be gained by classifying such cases as lying between the existing categories of contract and tort.


Hand Surgery ◽  
2015 ◽  
Vol 20 (03) ◽  
pp. 336-342 ◽  
Author(s):  
Michael A. Tonkin ◽  
Kerby C. Oberg

The Oberg, Manske and Tonkin (OMT) Classification of congenital anomalies of the hand and upper limb uses dysmorphological terminology, placing conditions in one of three groups: Malformations, Deformations and Dysplasias. The main group, Malformations, is further subdivided according to whether the whole of the limb is affected or the hand plate alone, and whether the primary insult involves one of the three axes of limb development and patterning or is non-axial. The common surgical diagnoses, such as thumb duplication and thumb hypoplasia, are then placed within this framework. Recently the International Federation of Societies for Surgery of the Hand Scientific Committee for Congenital Conditions approved the OMT Classification as a timely and appropriate replacement of the previously accepted Swanson Classification. This review charts the development of and modifications to the OMT Classification and its current status.


Author(s):  
Ingars Gusāns

The aim of the study is to describe the titles of Latvian metal music albums, from the perspective of content, by identifying the common and distinctive character of the metallic music tradition, and perhaps even the local one. Of 241 album titles (data on Dec. 31, 2019), most are in English, some in French, Latin, Russian, some consisting of digits, and 69 titles in Latvian. These titles are the subject of the research. The main source is Encyclopaedia Metallum (www.metal-archives.com), which still does not reflect the current situation concerning Latvian metal music. Album titles in this study are viewed separately from album designs and song titles and are analysed from the perspective of content. The album title is an important part of the work that has been issued because it is an element that makes the audience/buyer pay attention to the album because it must not be forgotten that today the album is also an item that you want to sell. In general, it can be concluded that Latvian metal musicians, with their album titles in Latvian, are mostly following world trends, as evidenced by the integration in the researcher Deena Weinstein’s classification of Dionysian discourse and discourse on chaos. Most titles are more relevant to the discourse on chaos because the thematic circle of chaos is wider. Latvian mythology, along with history, is an up-to-date source for the creative work of bands that is responsible for the local feeling of the titles. A large enough number are titles that are difficult to fit in the Weinstein’s division and form the third group with philosophical titles and simply all sorts of titles. If the philosophical titles follow the world’s trends, the simple titles include the names of the events, tributes, and the titles of literary works, which give them a local character.


2019 ◽  
Vol 46 (6) ◽  
pp. 511-521
Author(s):  
Lian Gu ◽  
Tae J. Kwon ◽  
Tony Z. Qiu

In winter, it is critical for cold regions to have a full understanding of the spatial variation of road surface conditions such that hot spots (e.g., black ice) can be identified for an effective mobilization of winter road maintenance operations. Acknowledging the limitations in present study, this paper proposes a systematic framework to estimate road surface temperature (RST) via the geographic information system (GIS). The proposed method uses a robust regression kriging method to take account for various geographical factors that may affect the variation of RST. A case study of highway segments in Alberta, Canada is used to demonstrate the feasibility and applicability of the method proposed herein. The findings of this study suggest that the geostatistical modelling framework proposed in this paper can accurately estimate RST with help of various covariates included in the model and further promote the possibility of continuous monitoring and visualization of road surface conditions.


2008 ◽  
Vol 24 (3) ◽  
pp. 419-429 ◽  
Author(s):  
Anthony Landreth ◽  
John Bickle

We briefly describe ways in which neuroeconomics has made contributions to its contributing disciplines, especially neuroscience, and a specific way in which it could make future contributions to both. The contributions of a scientific research programme can be categorized in terms of (1) description and classification of phenomena, (2) the discovery of causal relationships among those phenomena, and (3) the development of tools to facilitate (1) and (2). We consider ways in which neuroeconomics has advanced neuroscience and economics along each line. Then, focusing on electrophysiological methods, we consider a puzzle within neuroeconomics whose solution we believe could facilitate contributions to both neuroscience and economics, in line with category (2). This puzzle concerns how the brain assigns reward values to otherwise incomparable stimuli. According to the common currency hypothesis, dopamine release is a component of a neural mechanism that solves comparability problems. We review two versions of the common currency hypothesis, one proposed by Read Montague and colleagues, the other by William Newsome and colleagues, and fit these hypotheses into considerations of rational choice.


Author(s):  
Роман Рыбаков ◽  
Roman Rybakov

The article is devoted to legal fictions in regulating property relations in the English medieval common law (XIII—XVII centuries). Fictions are explained as features influencing the development of law, means of expansion of courts’ jurisdiction and mechanisms of the development of remedies protecting property relations. The article focuses on the role of fiction during the appellate review stage. Relevant case law is analyzed in this article. In this research the author uses the following set of methods of scientific cognition: dialectical method, historical method as well as special scientific research methods, such as technical legal method, comparative law method, formal legal method and legal interpretation method. This research results in better understanding of the role of fictions during the appellate review stage and provides analysis of differences between legal fictions used in the medieval civil law and the common law. In conclusion, the author suggests a classification of legal fictions’ functions in the medieval English common law.


Complexity ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Huiping Jiang ◽  
Demeng Wu ◽  
Rui Jiao ◽  
Zongnan Wang

Electroencephalography (EEG) is the measurement of neuronal activity in different areas of the brain through the use of electrodes. As EEG signal technology has matured over the years, it has been applied in various methods to EEG emotion recognition, most significantly including the use of convolutional neural network (CNN). However, these methods are still not ideal, and shortcomings have been found in the results of some models of EEG feature extraction and classification. In this study, two CNN models were selected for the extraction and classification of preprocessed data, namely, common spatial patterns- (CSP-) CNN and wavelet transform- (WT-) CNN. Using the CSP-CNN, we first used the common space model to reduce dimensionality and then applied the CNN directly to extract and classify the features of the EEG; while, with the WT-CNN model, we used the wavelet transform to extract EEG features, thereafter applying the CNN for classification. The EEG classification results of these two classification models were subsequently analyzed and compared, with the average classification accuracy of the CSP-CNN model found to be 80.56%, and the average classification accuracy of the WT-CNN model measured to 86.90%. Thus, the findings of this study show that the average classification accuracy of the WT-CNN model was 6.34% higher than that of the CSP-CNN.


2020 ◽  
Vol 3 (2) ◽  
pp. 73-89
Author(s):  
Paul Terkumbur ADEKE ◽  
Aper ZAVA ◽  
Manasseh TYOGO

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