On the fretting fatigue behavior of quenched and tempered steel in smooth point contact

Fretting fatigue can lead to a rapid decrease in the life of machine components when their contact surfaces have to transfer high tractions. Fretting fatigue was studied in partial, mixed and gross slip conditions made on quenched and tempered steel 34CrNiMo6. Measurements were made with sphere-on-plane contact geometry for smooth surfaces to detect macroscopic cracks. The fretting map type test series outlined a certain zone in partial and mixed slip conditions, where cracking occurred. The parameters affecting cracking threshold values and crack initiation are discussed

Spin-asymmetric graphene nanoribbons in graphane on silicon dioxide

Hydrogenated graphene, graphane, is studied on oxygen-terminated silicon dioxide substrate using ab initio calculations. A structure with hydrogenation only on one side of the graphene layer is found stable and its hydrogen configurations are presented. Additionally, we form zigzag graphene nanoribbons by selectively removing hydrogens from the epitaxial graphane layer. In these ribbons, the spin degeneracy of the freestanding antiferromagnetic zigzag ribbons is broken, and band gaps of different magnitude emerge for the opposite spin species. This degeneracy breaking is due to a charge imbalance in the substrate below the ribbon, introduced through the asymmetric alignment of the substrate atoms with respect to the edges of the graphene ribbon

Random binary search tree with equal elements

AbstractWe consider random binary search trees when the input consists of a multiset, i.e. a set with multiple occurrences of equal elements, and prove that the randomized insertion and deletion algorithms given by Martínez and Roura (1998) [4] produce random search trees regardless of multiplicities; even if all the elements are equal during the tree updates, a search tree will maintain its randomness. Thus, equal elements do not degenerate a random search tree and they need not to be handled in any special way. We consider also stability of a search tree with respect to its inorder traversal and prove that the algorithms used produce stable trees. This implies an implicit indexing of equal elements giving another proof that multiplicities do not pose problems when maintaining random binary search trees

Exploration of Ideas for Sustaining Digital Innovation Management : A Case Study in the Ostrobothnia Region of Finland

Disruption of technologies, climate changes and epidemic crises have significantly affected individuals, organizations, and society. These phenomena force organizations to extend and innovate their business models to adapt to new circumstances. However, literature provides a limited coverage on how sustainable innovations ideas form and evaluate in practice. We thus focus on this issue in the present study. We used nominal focus group technique, C-K design theory for innovative design with citizen sciences as our study’s lenses. Data collection was from three groups of 81 participants who live in three cities in the Ostrobothnia region of Finland. The findings illustrate the process of establishing a sustainable innovation management idea and lesson learned on how to facilitate innovation groups in practice.©2022 Association for Information Systems.fi=vertaisarvioitu|en=peerReviewed

Exploration of Ideas for Sustaining Digital Innovation Management: A Case Study in the Ostrobothnia Region of Finland

Disruption of technologies, climate changes and epidemic crises have significantly affected individuals, organizations, and society. These phenomena force organizations to extend and innovate their business models to adapt to new circumstances. However, literature provides a limited coverage on how sustainable innovations ideas form and evaluate in practice. We thus focus on this issue in the present study. We used nominal focus group technique, C-K design theory for innovative design with citizen sciences as our study’s lenses. Data collection was from three groups of 81 participants who live in three cities in the Ostrobothnia region of Finland. The findings illustrate the process of establishing a sustainable innovation management idea and lesson learned on how to facilitate innovation groups in practice

Symmetries and Observables for BF-theories in Superspace

The supersymmetric version of a topological quantum field theory describing flat connections, the super BF-theory, is studied in the superspace formalism. A set of observables related to topological invariants is derived from the curvature of the superspace. Analogously to the non-supersymmetric versions, the theory exhibits a vector-like supersymmetry. The role of the vector supersymmetry and an additional new symmetry of the action in the construction of observables is explained.Comment: 11 pages, LaTe

Slight respiratory irritation but not inflammation in mice exposed to (1-->3)-beta-D-glucan aerosols.

Airway irritation effects after single and repeated inhalation exposures to aerosols of beta-glucan (grifolan) were investigated in mice. In addition, the effects on serum total immunoglobulin E (IgE) production and histopathological inflammation in the respiratory tract were studied. The beta-glucan aerosols provoked slight sensory irritation in the airways, but the response was not concentration dependent at the levels studied. Slight pulmonary irritation was observed after repeated exposures. No effect was found on the serum total IgE levels, and no signs of inflammation were seen in the airways 6 h after the final exposure. The results suggest that, irrespective of previous fungal sensitization of the animals, inhaled beta-glucan may cause symptoms of respiratory tract irritation but without apparent inflammation. Respiratory tract irritation reported after inhalation of fungi may not be entirely attributed to beta-glucan