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941.
Jens G. Balchen 《Journal of Process Control》1999,9(2):101
The utilization of the results of control theory in the process control field has been lagging behind other application fields such as aerospace by many years. It is argued that the availability of high capacity computing at low price will change this situation and that new powerful control techniques can now be implemented in process control. 相似文献
942.
A Shrink Wrapping Approach to Remeshing Polygonal Surfaces 总被引:11,自引:0,他引:11
Leif P. Kobbelt Jens Vorsatz Ulf Labsik & Hans-Peter Seidel 《Computer Graphics Forum》1999,18(3):119-130
Due to their simplicity and flexibility, polygonal meshes are about to become the standard representation for surface geometry in computer graphics applications. Some algorithms in the context of multiresolution representation and modeling can be performed much more efficiently and robustly if the underlying surface tesselations have the special subdivision connectivity. In this paper, we propose a new algorithm for converting a given unstructured triangle mesh into one having subdivision connectivity. The basic idea is to simulate the shrink wrapping process by adapting the deformable surface technique known from image processing. The resulting algorithm generates subdivision connectivity meshes whose base meshes only have a very small number of triangles. The iterative optimization process that distributes the mesh vertices over the given surface geometry guarantees low local distortion of the triangular faces. We show several examples and applications including the progressive transmission of subdivision surfaces. 相似文献
943.
Window opening in passive solar dwellings Discussions of the user influence on the heating energy consumption of buildings are often controversial. A particularly significant issue is the opening of windows. However, concrete data about user behaviour are rarely available, and the actual consequences of open windows on the heating energy consumption are not understood very well. Based on measured data, this paper discusses the duration of additional window opening in passive solar dwellings, typical behaviour patterns, influence factors and the consequences on the heating energy consumption. Window opening during the summer is also considered. The study is based on measurements carried out at the passive solar housing development in Wiesbaden‐Dotzheim [1], [2] during 2001 and 2002. 相似文献
944.
Design for Bending and Bending with axial force of Ultra High Performance Concrete Ultra high performance concrete (UHPC) differs from normaland high strength concrete by having a more compact material structure. The UHPC components show a higher resistance against mechanical abrasions and freeze‐thaw‐stress as well as a greater impermeability for fluids and gases. Without adding steel fibres UHPC is a very brittle material, which fails abruptly. A ductile material behaviour can be reached by using steel fibres. This article describes how to design a UHPC for bending and bending with axial force by generating stress‐strain‐relation. 相似文献
945.
Carolin Czauderna Kim Luley Nikolas von Bubnoff Jens U. Marquardt 《International journal of molecular sciences》2021,22(21)
Liver metastases are the most common site of metastatic spread in colorectal cancer. Current treatment approaches involve effective systemic therapies in combination with surgical and/or interventional strategies. Multimodal strategies greatly improved clinical outcomes of patients with metastatic colorectal cancer over the last decades. Identification of predictive and prognostic biomarkers helped to comprehensively refine individual targeted treatment approaches and resulted in median overall survival rates of 30 months or longer. Current guidelines, thus, recommend treatment selection according to patients’ performance status, tumor localization and stage as well as the tumor’s molecular and genetic status. Here, we outline the latest developments in molecular decision-making for patients with upfront resectable, potentially or initially unresectable and non/never-resectable colorectal cancer liver metastases. 相似文献
946.
947.
Jens A. Hammerl Andrea Barac Philipp Erben Julius Fuhrmann Ashish Gadicherla Franziska Kumsteller Anne Lauckner Felix Müller Stefan Hertwig 《International journal of molecular sciences》2021,22(21)
Yersinia (Y.) enterocolitica and Y. pseudotuberculosis are important zoonotic agents which can infect both humans and animals. To combat these pathogens, the application of strictly lytic phages may be a promising tool. Since only few Yersinia phages have been described yet, some of which demonstrated a high specificity for certain serotypes, we isolated two phages from game animals and characterized them in terms of their morphology, host specificity, lytic activity on two bio-/serotypes and genome composition. The T7-related podovirus vB_YenP_Rambo and the myovirus vB_YenM_P281, which is very similar to a previously described phage PY100, showed a broad host range. Together, they lysed all the 62 tested pathogenic Y. enterocolitica strains belonging to the most important bio-/serotypes in Europe. A cocktail containing these two phages strongly reduced cultures of a bio-/serotype B4/O:3 and a B2/O:9 strain, even at very low MOIs (multiplicity of infection) and different temperatures, though, lysis of bio-/serotype B2/O:9 by vB_YenM_P281 and also by the related phage PY100 only occurred at 37 °C. Both phages were additionally able to lyse various Y. pseudotuberculosis strains at 28 °C and 37 °C, but only when the growth medium was supplemented with calcium and magnesium cations. 相似文献
948.
Numerous reaction types in the field of iminium salts are performed in the gas‐solid and solid‐solid techniques in order to reach 100% yield. The stoichiometric runs are waste‐free and do not require costly workup. Frequently, iminium salts were avoided, as acid catalysis was dispensable. Thioureas and α‐halogenated ketones give a variety of 2‐aminothiazoles via thiuronium salts in quantitative yield. A new intramolecular solid‐state thermal condensation is reported. Enaminoketones are synthesized quantitatively from anilines and 1,3‐diketones without catalysis and those can be used for quantitative solid‐state 4‐cascade reactions. Solid paraformaldehyde is used to produce methylene imines and internally trapped methylene iminium salts. Benzoylhydrazones are produced again without catalysis in the solid state. Vacuum and ball‐mill techniques are particularly useful in the production of highly sensitive iminium salts. Hexahydro‐1,3,5‐triazines cyclorevert upon exposure to HCl gas to give solid arylmethylene iminium chlorides as new versatile reagents. These are used in arylaminomethylations of β‐naphthol and of themselves to give Troeger's bases in 3‐cascades. More direct are 4‐cascade Troeger's base syntheses by dissolving hexahydro‐1,3,5‐triaryltriazines in trifluoroacetic acid. Alkylations of imines with trimethyloxonium tetrafluoroborate and triphenylmethyl cation give highly sensitive quaternary iminium salts in the ball‐mill. The products are characterized by spectroscopic techniques and density functional theory (DFT) calculations at the B3LYP 6‐31G* level. Molecular movements in the crystal and surface passivation are investigated with atomic force microscopy (AFM) techniques. 相似文献
949.
Shraddha Supreeti Michael Fischer Mathias Fritz Jens Müller 《International Journal of Applied Ceramic Technology》2024,21(2):1180-1190
The growing applications and constant miniaturization of electronic devices and of low-temperature co-fired ceramics (LTCC) in various fields, such as aviation, telecommunications, automotive, satellite communications, and military, have led to an increase in the demand for LTCC. Such prospects arise due to the continuous scaling down of components and high-density interconnection in electronics packaging. This paper reports a technique for the transfer of high-resolution microstructures from silicon substrates to LTCC. In this method, gold and copper patterns were formed by photolithography, electrodeposition, and residual layer stripping on silicon substrate. Lithography provides the opportunity to create and transfer complex patterns for use in several different applications and electroplating enables the use of pure metal for excellent electrical properties. The developed structures were transferred onto a top layer of LTCC tape using hot embossing. Then, the subsequent layers were stacked, laminated, and sintered. A resolution of 1.5 μm after free sintering and 4.5 μm after pressure-assisted sintering was achieved. This distinctive method can be useful for several applications requiring high-resolution and superior electrical properties. 相似文献
950.
Jürgen Fabian Helmar Grls Rainer Beckert Jens Atzrodt 《Advanced Synthesis \u0026amp; Catalysis》1997,339(1):735-741
5-Ring-Cycloamidines – Deeply Colored Heterocycles with Unusual Properties. II. Molecular- and Electronic Structure The crystal and molecular structure of two N,N′-aryl-5-amino-imidazole-4-imides were detected by X-ray analysis. The structural parameters are discussed in conjunction with theoretical data obtained by density functional and ab initio quantum theory. The interpretation of the molecular structures derived from the X-ray diffraction study is made more difficult by statistic disorder or by enclosure of water in the crystal. The theory predicts a planar 5-amino-imidazole-4-imide parent structure with an energy barrier to H-transfer of about 25 kcal/mol (DFT RB3LYP/6-311+G** and ab initio G2(MP2) calculations). The CC bond of the five-membered ring is exceedingly long. CC-bond length elongation is also reported for oxalbisamidine. The structure of the parent compound is discussed in terms of polymethinic and antiaromatic substructures. Weinholds's Natural Bond Orbital (NBO) scheme and Natural Resonance Theory (NRT) as well as Schleyer's criterion of the Nucleus Independent Chemical Shift (NICS) is consulted to reveal the very nature of the unique bond system. 相似文献