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71.
OPTIMA 总被引:1,自引:0,他引:1
Hartmut Stadtler 《OR Spectrum》1991,13(2):103-114
Zusammenfassung Im Rahmen der Reorganisation des Landesbetriebes Hamburger Stadtreinigung wurden zur Erhöhung der Effizienz und Wirtschaftlichkeit verschiedene Planungs- und Steuerungsinstrumente eingeführt. Eines dieser Instrumente stellt das EDV-gestützte Planungssystem OPTIMA, zur täglichen Planung der Abfallentsorgung des Stadtgebietes der Freien und Hansestadt Hamburg dar.Die Abfallentsorgung wird mit einem hierarchischen System, bestehend aus vier Ebenen, geplant. Für eine der Ebenen — die tägliche Abfuhrplanung — wurde die Unterstützung durch ein Netzwerkflußmodell vorgeschlagen und auf einem Personal Computer implementiert.Neben dem Aufbau und der Funktionsweise werden auch weiterführende Einsatzmöglichkeiten des Planungssystems beschrieben und eine erste Beurteilung des Einsatzes vorgenommen.Dem Aufsatz liegt ein Projekt zugrunde, das der Autor während seiner Tätigkeit bei der Fa. SCS Informationstechnik GmbH, Hamburg durchgeführt hat. 相似文献
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Dr. Carolyn Vargas Prof. Dr. Gerald Radziwill Dr. Gerd Krause Dr. Anne Diehl Prof. Dr. Sandro Keller Dr. Nestor Kamdem Prof. Dr. Constantin Czekelius Annika Kreuchwig Dr. Peter Schmieder Dr. Declan Doyle Prof. Dr. Karin Moelling Dr. Volker Hagen Dr. Markus Schade Prof. Dr. Hartmut Oschkinat 《ChemMedChem》2014,9(7):1458-1462
PDZ (PSD‐95, Dlg, ZO‐1) domains are ubiquitous interaction modules that are involved in many cellular signal transduction pathways. Interference with PDZ‐mediated protein–protein interactions has important implications in disease‐related signaling processes. For this reason, PDZ domains have gained attention as potential targets for inhibitor design and, in the long run, drug development. Herein we report the development of small molecules to probe the function of the PDZ domain from human AF6 (ALL1‐fused gene from chromosome 6), which is an essential component of cell–cell junctions. These compounds bind to AF6 PDZ with substantially higher affinity than the peptide (Ile‐Gln‐Ser‐Val‐Glu‐Val) derived from its natural ligand, EphB2. In intact cells, the compounds inhibit the AF6–Bcr interaction and interfere with epidermal growth factor (EGF)‐dependent signaling. 相似文献
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Renoud R Borderon C Gundel HW 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2011,58(9):1975-1980
In this study, the real and imaginary parts of the complex permittivity of lead zirconate titanate ferroelectric thin films are studied in the frequency range of 100 Hz to 100 MHz. The permittivity is well fitted by the Cole-Cole model. The variation of the relaxation time with the temperature is described by the Arrhenius law and an activation energy of 0.38 eV is found. Because of its nonlinear character, the dielectric response of the ferroelectric sample depends on the amplitude of the applied ac electric field. The permittivity is composed of three different contributions: the first is due to intrinsic lattice, the second is due to domain wall vibrations, and the third is due to domain wall jumps between pinning centers. This last contribution depends on the electric field, so it is important to control the field amplitude to obtain the desired values of permittivity and tunability. 相似文献
75.
In this paper, we studied the behavior of silicon quantum dots (Si-QDs) after etching and surface oxidation by means of photoluminescence (PL) measurements, Fourier transform infrared spectroscopy (FTIR) and electron paramagnetic resonance spectroscopy (EPR). We observed that etching of red luminescing Si-QDs with HF acid drastically reduces the concentration of defects and significantly enhances their PL intensity together with a small shift in the emission spectrum. Additionally, we observed the emergence of blue luminescence from Si-QDs during the re-oxidation of freshly etched particles. Our results indicate that the red emission is related to the quantum confinement effect, while the blue emission from Si-QDs is related to defect states at the newly formed silicon oxide surface. 相似文献
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Summary Aliphatic polyformamidines have been synthesized by reaction of aliphatic diamines with triethyl orthoformate in presence of catalytic amounts of acetic acid. The reaction has been carried out in DMSO at 180°C. The polymer structure has been confirmed by IR and NMR spectroscopy. For determination of molecular weights 1H NMR end group signals have been used. 相似文献
80.
Hartmut Pawelski 《国际钢铁研究》1998,69(4-5):161-164
The friction measuring apparatus according to O. Pawelski, which is based on the strip drawing experiment, is used to determine friction coefficients in plastic shaping of metals. By implementing elastomer inlays into the drawing cheeks the same principle has been applied to the contact between metals and elastomeric media. The plastification of metal by the extremely shear-weak elastomer is possible, because it is completely constrained with metal, so that a sufficiently high hydrostatic pressure in the inlay is generated. Elementary theory in combination with FEM showed that the friction coefficient, calculated using only the global static equilibrium of forces, is in very good approximation with simply the mixture of the friction coefficient between metal strip and elastomer and the friction coefficient between metal strip and drawing cheek weighted with the corresponding contact areas. Drawing experiments with aluminium 99.5 or steel St 37 and polyurethane or soft rubber were carried out. The important influence of lubrication and roughness of the metal strip on the friction coefficient was investigated. 相似文献