Cognitive clamping geometries for monitoring elastic deformation in forming machines and processes

In the context of inline monitoring and controlling of forming processes, the distribution of acting forces on tool and forming machine causing elastic deformation of the clamping surfaces provides fundamental information on the resulting part quality whereas the inline detection is still challenging. This paper presents a novel method using the T-slot geometry as a cognitive area for inline analyzing of the elastic deformation of the tool-clamping surfaces. Using a newly developed sensor device, the elastic deformation state of the T-slot geometry under process forces is detected by strain measuring of a deformation body mounted inside the T-slot. The functionality principle of the sensor device and measuring method for process monitoring are demonstrated by simulation and experiments, demonstrating the potential for process control.     

Dppm stabilized nickelacyclic carboxylates as building blocks of oligonuclear nickel complexes

The reaction of 1,1-bis(diphenylphosphino)methane (dppm) and [py₂Ni(C₂H₄COO)] with trace amounts of water leads to the formation of the novel pentanuclear organonickel compound [(μ²-dppm)₂{Ni(C₂H₄COO)}₄ * Ni(OH)₂] (1) bearing nickel centres in square planar as well as in octahedral coordination sphere. In presence of NiBr₂, the related trinuclear complex [(μ²-dppm){Ni(C₂H₄COO)}₂ * NiOH(H₂O)(py)₂]⁺ Br^? (2) was isolated and characterized by elemental analysis, IR measurements and X-ray single crystal structural analysis. These compounds are rare examples of organonickel compounds with μ³-hydroxide ligands and to best of our knowledge the first nickelacyclic carboxylates stabilized by such simple inorganic compounds as ligands.     

Enantioselective Organocatalytic Synthesis of Arylglycines via Friedel–Crafts Alkylation of Arenes with a Glyoxylate Imine

The enantioselective organocatalytic synthesis of arylglycines has been developed employing 1 mol% of an enantiopure N‐triflyl phosphoramide Brønsted acid as organocatalyst. Various differently substituted phenylglycine derivatives can be synthesized in good to excellent yields and enantiomeric excesses based on a Friedel–Crafts alkylation of electron‐rich arenes with a glyoxylate imine. A novel protocol for the deprotection of the N‐tert‐butylsulfonyl (Bus) group has also been developed.     

A Novel Process for Selective Ruthenium‐Catalyzed Oxidation of Naphthalenes and Phenols

Arenes are selectively oxidized to the corresponding quinones employing ruthenium(2,2′,6′:2′′‐terpyridine)(2,6‐pyridinedicarboxylate) [Ru(tpy)(pydic] as catalyst and hydrogen peroxide as the terminal oxidant. Applying alkylated naphthalenes and phenols, benzo‐ and naphthoquinones are obtained in up to 93% yield. The industrially interesting oxidation of 2‐methylnaphthalene gave 74% of the corresponding quinones and 60% of menadione (vitamin K₃). 2,3,5‐Trimethylbenzoquinone which constitutes the key intermediate for vitamin E is obtained in 83% yield.     

A novel wideband space‐time channel simulator based on the geometrical one‐ring model with applications in MIMO‐OFDM systems

In this paper, we extend the geometrical one‐ring multiple‐input multiple‐output (MIMO) channel model with respect to frequency selectivity. Our approach enables the design of efficient and accurate simulation models for wideband space‐time MIMO channels under isotropic scattering conditions. Two methods will be provided to compute the parameters of the simulation model. Especially, the temporal, frequency and spatial correlation properties of the proposed wideband space‐time MIMO channel simulator are studied analytically. It is shown that any given specified or measured discrete power delay profile (PDP) can be incorporated into the simulation model. The high accuracy of the simulation model is demonstrated by comparing its statistical properties with those of the underlying reference model with specified correlation properties in the time, frequency and spatial domain. As an application example of the new MIMO frequency‐selective fading channel model, we study the influence of various channel model parameters on the system performance of a space‐time coded orthogonal frequency division multiplexing (OFDM) system. For example, we investigate the influence of the antenna element spacings of the base station (BS) antenna as well as the mobile station (MS) antenna. It turns out that an increasing of the antenna element spacing at the BS side results in a higher diversity gain than an increasing of the antenna element spacing at the MS side. Furthermore, the diversity gain brought in by space‐time block coding schemes is investigated by simulation. Our results show that transmitter diversity can significantly reduce the symbol error rate (SER) of multiple antenna systems. Finally, the influence of the Doppler effect and the impact of imperfect channel state information (CSI) on the system performance is also investigated. Copyright © 2009 John Wiley & Sons, Ltd.     

Fiber-optic laser sensor for mine detection and verification

What we believe to be a new optical approach for the identification of mines and explosives by analyzing the surface materials and not only bulk is developed. A conventional manually operated mine prodder is upgraded by laser-induced breakdown spectroscopy (LIBS). In situ and real-time information of materials that are in front of the prodder are obtained during the demining process in order to optimize the security aspects and the speed of demining. A Cr4+:Nd3+:YAG microchip laser is used as a seed laser for an ytterbium-fiber amplifier to generate high-power laser pulses at 1064 nm with pulse powers up to E(p) = 1 mJ, a repetition rate of f(rep.) = 2-20 kHz and a pulse duration of t(p) = 620 ps. The recorded LIBS signals are analyzed by applying neural networks for the data analysis.     

Solidly mounted ZnO shear mode film bulk acoustic resonators for sensing applications in liquids

Solidly mounted film bulk acoustic resonators (FBAR) operating at 850 MHz in the shear vibration mode have been fabricated. C-axis inclined zinc oxide (ZnO) thin films realized by modified reactive magnetron sputtering were used: Coupling factors k2 of 1.7% and Q-factors of 312 were determined in air. Q-factors of 192 were measured in water, making these devices attractive for sensing applications in liquids, e.g., biosensing.     

Deutsche Nationalbibliothek 4. Erweiterungsbau in Leipzig – Besonderheiten bei der Unterfangung und der Bestandssicherung

Derzeit entsteht der 4. Erweiterungsbau der Deutschen Nationalbibliothek in Leipzig. Der neue Baukörper grenzt bereichsweise an die Bestandsgebäude und wurde 6 bis 8 m unterhalb der bestehenden Fundamente gegründet. Der setzungsempfindliche Baugrund infolge eines 4 m mächtigen Kohleflözes musste in der Planung besonders berücksichtigt werden. Um die Bestandsgebäude gegen Setzungen, Rissbildungen und Schiefstellungen zu schützen, wurden außergewöhnliche Sicherungsmaßnahmen realisiert: –·Zusammenspannen der Gebäude mittels Anordnung von Zugstäben –·Auskreuzung gefährdeter Bereiche durch Holz‐Fachwerkverbände –·Anwendung einer besonderen Technologie der HDI‐Unterfangung. Mit diesen Maßnahmen konnten ungleichmäßige Setzungen und Rissbildungen weitestgehend vermieden werden. The German National Library in Leipzig – 4^th extension – Special features of the underpinning and safety measures of inventory. At present the 4^th extension of the German National Library in Leipzig is under construction. The new building is near the existing buildings and was founded in 6 to 8 m below the existing foundations. The ground is liable to subsidence due to a 4 m thick coal seam. This had to be specially considered in the planning. To protect the existing buildings against settlements, cracking and misalignment extraordinary safety measures were implemented: –·tensioning arrangement of buildings by means of tension bars –·strengthening of vulnerable areas by timber trussed bond –·using a special technology of grouted underpinning With these measures, non‐uniform settlements and cracks could be largely avoided.     

Hochwasserschutz im Land Bremen – Anpassung an prognostizierte Klimaänderungen

Im Beitrag wird auf Besonderheiten bei der Umsetzung des Generalplans Küstenschutz Niedersachsen/Bremen im Land Bremen eingegangen. Im ersten Teil werden die Grundlagen und Ergebnisse des Generalplans sowie die administrative Aufstellung des Landes Bremen zur Anpassung des Hochwasserschutzes beschrieben. Das Instrument der Kostenvergleichsrechnung wird vorgestellt, welches in Bremen bereits im frühen Projektstadium zur Bewertung der Vorzugslösungen eingesetzt wird. Ein wichtiger Aspekt bei der Umsetzung des Generalplans sind die technischen Anforderungen, die sich aus den bestehenden Hochwasserschutzanlagen ergeben. Weiterhin müssen im Land Bremen die Maßnahmen zum Hochwasserschutz im Wesentlichen unter Berücksichtigung der bestehenden konstruktiv geprägten Ufer (Spundwände und Kaianlagen) umgesetzt werden. Dabei sind spezielle Anforderungen hinsichtlich der aktuellen und zukünftigen Nutzung insbesondere in den Hafenrevieren zu berücksichtigen. Beispielhaft werden begleitende Projekte der INROS LACKNER AG vorgestellt. Flood protection in the Federal State and the city of Bremen by adjustment of climate changes. The present article describes how the Federal State and the Free Hanseatic City of Bremen adapts its flood protection with respect to climate changes and global sea level rise. Design basics are compiled in the “Generalplan Küstenschutz Niedersachsen/Bremen” (General Plan for Coastal Protection – Lower Saxony/Bremen). Main results of the general plan will be described and administrative aspects of the adaptation of the flood protection elements in Bremen will be lined out. Special technical requirements as the consideration of existing walls and dikes will be described. Also requirements from harbour operation, recreational use and urban architecture have to be considered as the Bremen port partly undergoes a rapid change in this regard. The instrument of cost analysis will be introduced which is utilised in Bremen at an early stage of planning in order to develop cost effective measures of public founded projects. Mentioned topics will be described based on projects carried out by INROS LACKNER AG.