Specifics of forming using elastomers

Práce obsahuje přehled metod tváření využívajících elastomerový nástroj včetně rozdělení jednotlivých nástrojů a vhodnosti k daným operacím. Tváření elastomery se řadí mezi nekonvenční metody tváření pomocí pružného nástroje, které je vhodné zejména pro tváření plechů. Jako materiál se používá pryž a polyuretan. Jsou zde také uvedeny vlastnosti, tvářecí síly a další zajímavosti elastomerů. Princip spočívá v nahrazení pevné části nástroje pružným médiem. Metody tváření jsou rozděleny podle konstrukce nástroje, na tváření otevřeným nástrojem a tváření uzavřeným nástrojem. Tváření otevřeným nástrojem zahrnuje ohýbání a zakružování. Mezi tváření uzavřeným nástrojem patří metody Guerin, Marform, Maslenikov, radiální vypínání a protlačování. Dále jsou uvedeny ukázky nástrojů a odlišnosti oproti konvenčním metodám a kapalinám. Výhodou elastomerového nástroje je nízká cena, jednoduchost a šetrnost k povrchově upraveným výrobkům. Nevýhodou je nízká životnost, nízká produktivita a použití velkých tvářecích sil. Tváření elastomery má uplatnění v kusové a malosériové výrobě.The thesis contains a review of methods using elastomer tool, including the distribution of tools and suitability to the operations. Forming using elastomers is among the unconventional forming methods using flexible tool which is especially suitable for sheet metal forming. The material is used rubber and polyurethane. There are described properties, forming forces and other attractions of elastomers. The principle consists in replacing the fixed part of the tool flexible medium. Forming methods are divided to open tool forming and close tool forming, according to the construction of forming tool. Open tool forming includes bending and roll bending. Among the close tool forming methods is Guerin, Marform, Maslenikov, radial expanding and extrusion. The following are examples of tools and differences compared to conventional methods and liquids. The advantage of elastomeric tool is a low cost, simplicity and frugality to surface modified products. The disadvantage is a low life, low productivity and the use of large forming forces. Forming using elastomers has application in the prototypes and small series production.

Checklist of marine and estuarine fishes from the Alaska–Yukon Border, Beaufort Sea, to Cabo San Lucas, Mexico

This paper is a checklist of the fishes that have been documented, through both published and unpublished sources, in marine and estuarine waters, and out 200 miles, from the United States-Canadian border on the Beaufort Sea to Cabo San Lucas, Mexico. A minimum of 241 families and 1,644 species are known within this range, including both native and nonnative species. For each of these species, we include maximum size, geographic and depth ranges, whether it is native or nonnative, as well as a brief mention of any taxonomic issues

The Expanding Role of Natural History Collections

Museum specimens serve as the bedrock of systematic and taxonomic research and provide the basis for repeatability or reinterpretation of preserved aspects of phenotypes. Specimens are also fundamental to fields such as ecology, behavior, and development. Each specimen is a record of biodiversity and documents a particular species present at a particular place at a particular time. As such, specimens can provide key evidence for biodiversity and conservation initiatives. Four aspects of natural history collections and their use are discussed here: 1) collection, curation, and use of specimens, particularly non-traditional specimens; 2) the use of specimens and technological advances in morphology, ontogeny, systematics, and taxonomy; 3) specimen use in other fields of biology and ecology; and 4) specimen use in education and outreach. Collections, and their vitality, depend on both their continued roles in traditionally supported fields (e.g., taxonomy) as well as emerging arenas (e.g., epidemiology). Just as a library that ceases buying books becomes obsolete, or at least has diminished relevance, a natural history collection that does not continue to grow by adding new specimens ultimately will limit its utility. We discuss these roles of specimens and speak directly to the need to increase the visibility of the inherent value of natural history collections and the care of the specimens they protect for future generations

Utilization of an elastic tool made of polyurethane in forming technologies

ZIGÁČEK Štěpán: Využití nepevného nástroje – polyuretanu – ve tváření Projekt vypracovaný v rámci bakalářského studia oboru B-STI Strojní inženýrství je literární studií zaměřenou na výrobní metody tváření pomocí elastomerů. Rešerše se zabývá základním rozdělením a principy všech možných způsobů využití elastomerů se zaměřením na využití polyuretanu s ukázkami použití a vyhodnocením jejich výhod a nevýhod.ZIGÁČEK Štěpán: Utilization of an elastic tool made of polyurethane in forming technologies This project elaborated within bachelor study program B-STI Mechanical engineering is literary study focused on manufacturing methods of forming by elastomers. The recherche deals with the basic division and principles of all possible utilizations of elastomers focusing on the usage of polyurethane with examples and evaluation of their advantages and disadvantages.

Lenses as an Atom-Photon Interface: A Semiclassical Model

Strong interaction between the light field and an atom is often achieved with cavities. Recent experiments have used a different configuration: a propagating light field is strongly focused using a system of lenses, the atom being supposed to sit at the focal position. In reality, this last condition holds only up to some approximation; in particular, at any finite temperature, the atom position fluctuates. We present a formalism that describes the focalized field and the atom sitting at an arbitrary position. As a first application, we show that thermal fluctuations do account for the extinction data reported in M. K. Tey et al., Nature Physics 4, 924 (2008)

The transformation of traditional banking activity in digital

Purpose: This article investigates specifics of the transformation of banking activity in the conditions of digitalization of the economy. In the light of penetration of digital technologies into all the spheres of our life, the rapid development of financial technologies and their active implementation in the banking sector of the economy, digital financial innovations are formed at the intersection of the concepts of "financial technologies" and "financial innovations". Design/Methodology/Approach: In order to investigate the process of transformation of the banking sector in the context of digitalization, it is necessary to consider this issue from three points of view: 1) theoretical understanding of the concept of "financial technologies"; 2) the need to ensure the efficiency and sustainability of the banking sector; 3) the change in the IT- architecture of banking activities and the formation of the digital ecosystem with banks in the center. It is also reasonable to analyze promising areas of implementation of financial technologies into the banking sector. Findings: The main directions of the development of financial technologies in the banking sector, aimed at further transformation of traditional banking services through digital technologies. Practical Implications: The results of the study can be applied in the development of the legislative regulation of the FinTech industry in Russia. Originality/Value: The main contribution of this study is to determine the prospects for the development of the domestic banking sector in the context of digitalization, the need to transform in order not only to improve the competitiveness and efficiency of functioning, but also to stay in the banking business.peer-reviewe

Scalable TriDAS for the NEMO project

Abstract The data acquisition for the NEMO km 3 detector is based on the all data to shore approach. The continuous data stream, coming from more than 8000 PMTs, will be greater than 32 GBps, and therefore it requires a fast on-line filtering for an appropriate noise suppression. An on-shore multi-system Trigger Infrastructure has been studied to handle and real-time analyze such an amount of data. In order to accomplish the data acquisition of the NEMO prototype tower, expandable algorithms and services for data handling, system control and monitoring have been prepared

Triglops dorothy, a new species of sculpin (Teleostei: Scorpaeniformes: Cottidae) from the southern Sea of Okhotsk

A new species of the cottid genus Triglops Reinhardt is described on the basis of 21 specimens collected in Aniva Bay, southern Sakhalin Island, Russia, and off Kitami, on the northern coast of Hokkaido, Japan, at depths of 73–117 m. Of the ten species of Triglops now recognized, the new species, Triglops dorothy, is most similar to T. pingeli Reinhardt, well known from the North Atlantic and North Pacific oceans and throughout coastal waters of the Arctic. The new species differs from T. pingeli in a combination of morphometric and meristic characters that includes most importantly the number of dorsolateral scales; the number of oblique, scaled dermal folds below the lateral line; and the number of gill rakers

Ignition Features of Plasma-Beam Discharge in Gas-Discharge Electron Gun Operation

The current paper presents the results of experimental researches to determine the mode features of plasma-beam discharge (PBD) generation by an electron beam injected by a low-vacuum gasdischarge electron gun (LGEG) with the cold cathode and hollow anode on the basis of the high-voltage glow discharge and in the range of helium pressure of P ? 10 ÷ 130 Pa. The PBD boundaries and their dependences on parameters of an electron beam are found. The influence of PBD on parameters of low-vacuum gas-discharge electron gun is revealed. It causes an avalanche increase of electron beam current and burning of plasma-beam discharge in the whole space of the vacuum chamber volume and generation of electromagnetic radiation is revealed. Achieved results will be used for implementation of various vacuum technologies in the medium of reaction gas and generated electromagnetic radiation