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241.
H. Maurer O. Univ.-Prof. Dr. phil. 《e & i Elektrotechnik und Informationstechnik》2003,120(11):411-413
In this article it is argued that in ten years’ time personal computers as we know them now won’t exist anymore — all their functions will by then be integrated in mobiles which will be our steady companions. As such, mobiles will change our lives to an enormous extent. Technology as well as consequences will be discussed in this paper. 相似文献
242.
C. Arunachalaperumal Dr. C. Arun S. Dhilipkumar G. Abija 《Journal of Communications Technology and Electronics》2014,59(11):1247-1252
In recent years, it has been realized that the Multiple Input Multiple Output (MIMO) communication system is inevitable in accelerating the evolution of high data rate applications. Also the latest research in Information and Communication Technology has told that considerable gains in capacity of wireless communication are feasible in MIMO systems. MIMO with Space Time Trellis Code (STTC) offers both diversity gain and coding gain. This paper discusses the evolutional variants of Space Time Trellis Code developed over a decade. The performance of New Trellis code for STTC, STTC for 4-PSK, Space Frequency Trellis code (SFTC), Space Time Bit Trellis Code, and Silver STTC have been studied and discussed. STTC with Trellis Coded Modulation creates a bandwidth efficient system with coding gain. 相似文献
243.
David C. Lamb Diane E. Kelly Michael R. Waterman Maria Stromstedt Damjana Rozman Steven L. Kelly 《Yeast (Chichester, England)》1999,15(9):755-763
Human and Candida albicans CYP51 were purified to homogeneity after GAL10‐based heterologous expression in yeast in order to resolve the basis for the selective inhibition of the fungal enzyme over the human orthologue by the azole drugs ketoconazole and itraconazole, used in the treatment of systemic fungal infection. The purified proteins have similar spectral characteristics, both giving a maximum at 448 nm in reduced carbon monoxide difference spectra. Substrate affinity constants of 20·8 and 29·4 μM and Vmax of 0·15 and 0·47 nmol/min/nmol were observed for C. albicans and human enzymes, respectively, in reconstituted enzymatic assays, using an intermediate of the demethylation reaction [32‐3H]‐3β‐hydroxylanost‐7‐en‐32‐ol as the substrate. Both enzymes gave similar type II spectra on titration with drugs, but a reduced affinity was observed for human CYP51 using the ability of carbon monoxide to displace the drug as a ligand and by calculation of IC50. However, although the results indicate higher affinity of the drugs for their target CYP51 in the major fungal pathogen C. albicans, when compared directly to CYP51 from humans, the difference was less than 10‐fold. This difference is an order of magnitude lower than previously reported data based on measurements using unpurified human CYP51 enzyme preparations. Consequently, increased azole doses to combat resistant candidaemia may well inhibit endogenous human CYP51 and the potential consequences are discussed. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
244.
Dr. techn. Dr. tekn. h.c. Prof. Emeritus J?rgen Bach Andersen M.Sc. Ph.D. Prof. Gert Fr?lund Pedersen 《e & i Elektrotechnik und Informationstechnik》2012,129(6):383-386
In future mobile communications many antennas will coexist on the device. This creates a number of problems related to bandwidth, efficiency, and correlation. Remedies are discussed in the paper, and attention is called to the promising area of adaptive matching, which also can solve problems related to the user. 相似文献
245.
246.
Keith A Lidke Bernd Rieger Diane S Lidke Thomas M Jovin 《IEEE transactions on image processing》2005,14(9):1237-1245
Anisotropy imaging can be used to image resonance energy transfer between pairs of identical fluorophores and, thus, constitutes a powerful tool for monitoring protein homo-association in living single cells. The requirement for only a single fluorophore significantly simplifies biological preparation and interpretation. We use quantitative methods for the acquisition and image processing of anisotropy data that return the expected error of the anisotropy per pixel based on photon statistics. The analysis methods include calibration procedures and allow for a balance in spatial, anisotropy, and temporal resolution. They are featured here with anisotropy images of fluorescent calibration beads and enhanced green fluorescent protein complexes in live cells. 相似文献
247.
A. Molisch Prof. Dipl.-Ing. Dr. techn. 《e & i Elektrotechnik und Informationstechnik》2005,122(3):85-90
MIMO (multiple-input-multiple-output) systems propose enormous gains in the capacity of wireless systems without requiring more spectral resources. This paper first gives an overview of the use of MIMO for diversity and spatial multiplexing, and the use of channel state information in MIMO systems. It then explores the use of antenna selection as a means for the reduction of the hardware complexity. It is shown that the performance in a spatial-multiplexing application is almost as good as that of full-complexity systems as long as the number of RF chains is at least as large as the number of data streams. 相似文献
248.
A. Kugi Univ.-Prof. Dipl.-Ing. Dr. techn. T. Kiefer Dipl.-Ing. 《e & i Elektrotechnik und Informationstechnik》2005,122(9):300-307
This contribution is devoted to the nonlinear tracking control problem of the laboratory experiment helicopter 3DOF distributed by Quanser. The laboratory experiment belongs to the class of mechanical systems with three degrees-of-freedom and two control inputs. It is well known that the systematic design of nonlinear controllers for underactuated mechanical systems is a challenge compared to fully actuated systems. On certain simplifying assumptions, which very well apply to the operating range of practical interest, we can show that the mathematical model is configuration flat. Thereby, a mechanical system is said to be configuration flat if it is differential flat and the flat outputs solely depend on the generalized coordinates of the mechanical system. The controller design is based on a formulation of the mechanical system on a Riemannian manifold where the kinetic energy serves as a natural Riemannian metric. In a first step a nonlinear tracking controller including an integral part in the linear error system is designed by means of a quasi-static state feedback. In a second step the design of the tracking controller is based on the theory of exact linearization utilizing the so-called dynamic extension algorithm. The experimental results of both controllers are compared and discussed in detail. In particular, the quasi-static state feedback controller shows an excellent tracking behavior. The performance as being obtained by the nonlinear controlled cannot be achieved by conventional linear control strategies. 相似文献
249.
S. Fuchshumer Dipl.-Ing. K. Schlacher O. Univ.-Prof. Dipl.-Ing. Dr. techn. T. Rittenschober Mag. Dipl.-Ing. 《e & i Elektrotechnik und Informationstechnik》2005,122(9):319-324
This contribution is primarily concerned with the system analysis of the bicycle dynamics, revealing the differential flatness property as a main result. A physically relevant representative for the flat output is introduced, with its components given as the lateral and the longitudinal velocity of a distinguished point located on the longitudinal axis of the vehicle. This flatness property is shown for the front-, rear- and all-wheel driven vehicle, without referring to particular representatives of the functions modelling the lateral tire forces. Following the flatness based control theory, a novel approach to nonlinear vehicle dynamics control is discussed. 相似文献
250.
This study investigated jurors' reactions to judges' nonverbal communication in mock trials. Participants in 80 mock juries viewed taped segments of direct and cross examination that varied the judges' level of nonverbal involvement. Comments about the judge were solicited in predeliberation questionnaires and unsolicited comments obtained from dialogue that occurred during mock jury deliberations. The investigation found that jurors are aware of nonverbal cues from judges, particularly negative behaviors. Although the high- and low-involved judges solicited roughly the same number of comments, more negative comments were made about the judge displaying low than high nonverbal involvement. The results also revealed that jurors made more negative comments than positive ones. Overall, jurors are most aware of a judge's lack of involvement and apparent bias. Discussion focuses on ways to minimize the influence of judge nonverbal communication on jurors. 相似文献