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71.
An gerasterten Schichtproben Messung des örtlichen Formänderungsverlaufes im Walzgut beim Warmwalzen von Stahl St 37 in Raute-, Oval-, Trapez- und Quadratkalibern. Einflu$sZ von Form und Abmessungsverhältnis der Kaliber in Verbindung mit der Geometrie des einlaufenden Walzgutes auf die Formänderungsverteilung. Vergleich und Wertung der Kaliberfolgen. Geeignete kalibrierungstechnische Ma$sZnahmen bewirken einen gewünschten Formänderungsverlauf.  相似文献   
72.
Abstract

Fluorescence antibunching from single terrylene molecules embedded in a cholesteric-liquid-crystal host is used to demonstrate operation of a room-temperature single-photon source. One-dimensional (1-D) photonic-band-gap microcavities in planar-aligned cholesteric liquid crystals with band gaps from visible to near-infrared spectral regions are fabricated. Liquid-crystal hosts (including liquid crystal oligomers and polymers) increase the source efficiency, firstly, by aligning the dye molecules along the direction preferable for maximum excitation efficiency (deterministic molecular alignment provides deterministically polarized output photons), secondly, by tuning the 1-D photonic-band-gap microcavity to the dye fluorescence band and thirdly, by protecting the dye molecules from quenchers, such as oxygen. In our present experiments, using oxygen-depleted liquid-crystal hosts, dye bleaching is avoided for periods exceeding one hour of continuous 532 nm excitation.  相似文献   
73.
Abstract

This article studies the problem of detecting sequentially stationary error terms in a multiple regression model with a difference-stationary multivariate I(1)-regressor. The detection of cointegration is covered as a special case. We provide the asymptotic distribution theory for a monitoring procedure that is related to a well-known nonparametric unit root test statistic calculated from sequentially updated least squares residuals. Functional limit theorems for the corresponding sequential processes and central limit theorems for the detectors used to raise an alarm are established under the no-change null hypothesis as well as under change-point models covering a change to I(0)-errors and a change of the regression coefficients as well. We also discuss extensions to the case that continuous time processes are discretely sampled to obtain the data allowing to apply the procedures to high-frequency data as well. Our results show that we can handle the infill asymptotics assuming that nonstationary continuous-time processes such as semimartingales are discretely observed, by virtue of the general assumptions that we impose. The finite sample properties are investigated by a simulation study.  相似文献   
74.
Here we describe a new quadrupole Fourier transform ion cyclotron resonance hybrid mass spectrometer equipped with an intermediate-pressure MALDI ion source and demonstrate its suitability for "bottom-up" proteomics. The integration of a high-speed MALDI sample stage, a quadrupole analyzer, and a FT-ICR mass spectrometer together with a novel software user interface allows this instrument to perform high-throughput proteomics experiments. A set of linearly encoded stages allows sub-second positioning of any location on a microtiter-sized target with up to 1536 samples with micrometer precision in the source focus of the ion optics. Such precise control enables internal calibration for high mass accuracy MS and MS/MS spectra using separate calibrant and analyte regions on the target plate, avoiding ion suppression effects that would result from the spiking of calibrants into the sample. An elongated open cylindrical analyzer cell with trap plates allows trapping of ions from 1000 to 5000 m/z without notable mass discrimination. The instrument is highly sensitive, detecting less than 50 amol of angiotensin II and neurotensin in a microLC MALDI MS run under standard experimental conditions. The automated tandem MS of a reversed-phase separated bovine serum albumin digest demonstrated a successful identification for 27 peptides covering 45% of the sequence. An automated tandem MS experiment of a reversed-phase separated yeast cytosolic protein digest resulted in 226 identified peptides corresponding to 111 different proteins from 799 MS/MS attempts. The benefits of accurate mass measurements for data validation for such experiments are discussed.  相似文献   
75.
A product that is adapted individually to a specific market segment, that is innovative, and that is constructed aesthetically, will be successful. In this process there is a triangular relationship between designer, client, company and market, where functional communication has to be ensured. Globally the market has segmented into age groups, so that aesthetic attitudes are independent of nationality. Design should distinguish a product from the mass by accentuating its individual characteristics and so enable the consumer to identify with it. Today's design determines tomorrow's quality of life. This article describes the process of product development as exampled by the Wenger 1/1 Office Printer.

The design development procedure is divided into three phases: (a) planning phase; (b) project phase; (c) realization phase. The printer market is described, and the most important product requirements defined. The design concept was that a product should be developed that combined the advantages of impact- and non-impact printing techniques with a new, market-influencing design, There were two options with regard to the Wenger 1/1; [a) mechanical and electronic parts combined in one housing; (b) mechanical and electronic parts in separate housings. In order to ensure optimal noise silencing, option (b) was chosen. The favored option was realized in a foam-rubber model, and details worked out. A 'function-model' was manufactured and tested to ensure performance and market-adjustment of the new product. The designer and the client then liaised to supervise the product through to serial manufacture.  相似文献   
76.
Channel estimation techniques for CDMA system need to combat multiple access interference (MAI) to improve the estimation performance. The linear MMSE detector has certain advantages with respect to the near–far problem and can be used to develop a channel estimation algorithm. In this paper, an efficient iterative method for near–far resistant single-user mobile radio channel estimation in slow fading multi-path direct sequence code division multiple access (DS-CDMA) channels is presented. Computer simulation results demonstrate that a significant performance improvement can be achieved with the proposed method especially under extreme near–far conditions.  相似文献   
77.
Authoring of multimedia content can be considered as composing media assets such as images, videos, text, and audio in time, space, and interaction into a coherent multimedia presentation. Personalization of such content means that it reflects the users’ or user groups’ profile information and context information. Enriching the multimedia content with semantically rich metadata allows for a better search and retrieval of the content. To actually create personalized semantically-rich multimedia content, a manual authoring of the many different documents for all the different users’ and user groups’ needs is not feasible. Rather a (semi-)automatic authoring of the content seems reasonable. We have analyzed in detail today’s approaches and systems for authoring, personalizing, and semantically enriching multimedia presentations. Based on this analysis, we derived a general creation chain for the (semi-)automatic generation of such content. In this paper, we introduce this creation chain. We present our software engineering support for the chain, the component framework SemanticMM4U. The canonical processes supported by the creation chain and SemanticMM4U framework are described in detail. We also provide an explicit mapping of SemanticMM4U framework components to the processes and argue for the benefits of defining canonical processes for creating personalized semantically rich multimedia presentations.  相似文献   
78.
In the single middle leg preparation of the stick insect walking on a treadmill, the activity of flexor and extensor tibiae motor neurons and muscles, which are responsible for the movement of the tibia in stance and swing phases, respectively, was investigated with respect to changes in stepping velocity. Changes in stepping velocity were correlated with cycle period. There was a close correlation of flexor motor neuron activity (stance phase) with stepping velocity, but the duration and activation of extensor motor neurons (swing phase) was not altered. The depolarization of flexor motor neurons showed two components. At all step velocities, a stereotypic initial depolarization was generated at the beginning of stance phase activity. A subsequent larger depolarization and activation was tightly linked to belt velocity, i.e. it occurred earlier and with larger amplitude during fast steps compared with slow steps. Alterations in a tonic background excitation appear not to play a role in controlling the motor neuron activity for changes in stepping velocity. Our results indicate that in the single insect leg during walking, mechanisms for altering stepping velocity become effective only during an already ongoing stance phase motor output. We discuss the putative mechanisms involved.  相似文献   
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