Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Book
    Book
    Contact problems in elasticity : a study of variational inequalities and finite element methods (1988)
    Philadelphia, PA :Society for Industrial and Applied Mathematics,
    Details
    Title: Contact problems in elasticity : a study of variational inequalities and finite element methods
    Author: Kikuchi, N.
    Contributer: Oden, John T.
    Publisher: Philadelphia, PA :Society for Industrial and Applied Mathematics,
    Year of publication: 1988
    Pages: XIII, 495 S.
    Series Statement: SIAM studies in applied mathematics
    ISBN: 0-89871-202-5
    Type of Medium: Book
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    ZIB Catalog
    Zuse Institute Berlin get availability status
  • 2
    Electronic Resource
    Electronic Resource
    A mutant trypsin-like enzyme from Streptomyces fradiae, created by site-directed mutagenesis, improves affinity chromatography for protein trypsin inhibitors (1996)
    Springer
    Applied microbiology and biotechnology 46 (1996), S. 15-21 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The Ser-170 residue of a trypsin-like enzyme from Streptomyces fradiae (SFT), which is considered to be the active-site serine, was replaced with alanine by site-directed mutagenesis to improve the affinity chromatography step for a Kazal-type trypsin inhibitor, pancreatic secretory trypsin inhibitor (PSTI). The resulting mutant SFT, designated as [S170A]SFT, was expressed in Streptomyces lividans and purified to homogeneity. [S170A]SFT was catalytically inactive, but still had the ability to bind tightly to PSTI and to soybean trypsin inhibitor with dissociation constants of 3.1×10-7 M and 1.9×10-8 M respectively. We further demonstrated that recombinant human PSTI secreted into Saccharomyces cerevisiae culture broth could be purified to homogeneity with a one-step [S170A]SFT-affinity column. The purified PSTI contained no molecules intramolecularly cleaved by active trypsin, which are found when trypsin-affinity chromatography is used for the purification. This eliminated the need for further separation of intact PSTI from intramolecularly cleaved PSTI by high-performance liquid chromatography, thus simplifying and improving its purification process.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050777
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    CT and MR findings of torsion of greater omentum: a case report (1997)
    Springer
    Abdominal imaging 22 (1997), S. 45 -46 
    Details
    ISSN: 1432-0509
    Keywords: Key words: Torsion—Greater omentum—Diagnosis—CT—MR.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract. We report a case of torsion of the greater omentum, which occurred in a 39-year-old man with an adhesive inguinal hernia. Preoperative computed tomography and magnetic resonance (MR) imaging showed a characteristic whirling fatty mass occupying the middle and lower abdomen anteriorly. MR imaging also showed difference of intensities in the twisted omentum, suggesting the presence of the pathological conditions of edema or congestion.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002619900136
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Optima topology design of structures under dynamic loads (1999)
    Springer
    Structural optimization 17 (1999), S. 208-218 
    Details
    ISSN: 0934-4373
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract When elastic structures are subjected to dynamic loads, a propagation problem is considered to predict structural transient response. To achieve better dynamic performance, it is important to establish an optimum structural design method. Previous work focused on minimizing the structural weight subject to dynamic constraints on displacement, stress, frequency, and member size. Even though these methods made it possible to obtain the optimal size and shape of a structure, it is necessary to obtain an optimal topology for a truly optimal design. In this paper, the homogenization design method is utilized to generate the optimal topology for structures and an explicit direct integration scheme is employed to solve the linear transient problems. The optimization problem is formulated to find the best configuration of structures that minimizes the dynamic compliance within a specified time interval. Examples demonstrate that the homogenization design method can be extended to the optimal topology design method of structures under impact leads.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01195945
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Topology optimization of compliant mechanisms with multiple outputs (1999)
    Springer
    Structural optimization 17 (1999), S. 269-278 
    Details
    ISSN: 0934-4373
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract A procedure for the topology design of compliant mechanisms with multiple output requirements is presented. Two methods for handling the multiple output requirements are developed, a combined virtual load method and a weighted sum of objectives method. The problem formulations and numerical solution procedures are discussed and illustrated by design examples. The examples illustrate the capabilities of the design procedure, the effect of the direction of the output deflection requirements on the solution, as well as computational issues such as the effect of the starting point and effect of the material resource constraint.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01207003
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Optimization of 2-D structures subjected to nonlinear deformations using the homogenization method (1999)
    Springer
    Structural optimization 17 (1999), S. 286-299 
    Details
    ISSN: 0934-4373
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The generalized layout optimization method is applied to nonlinear problems. The algorithm was originally invented by Bendsøe and Kikuchi (1988), where an admissible design domain is assumed to be composed of periodic microstructures with tiny cavities; the sizes and the rotational angle of the cavities are defined as design variables which are optimized to minimize the applied work. The macroscoic material tensor of the porous material is calculated by the homogenization method for the sensitivity analysis. In order to apply it to nonlinear problems, we present a 2-D database of the material tensor calculated by the elasto-plastic homogenization method and an interpolation technique of the database for the practical computation. Several numerical examples of 2-D structures and a thin shell are shown to demonstrate the effectiveness of our algorithms. The algorithm is also extended to the finite deformation problems, and a practical optimized design is exhibited.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01207005
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Transgenic cucumber plants harboring a rice chitinase gene exhibit enhanced resistance to gray mold (Botrytis cinerea) (1998)
    Springer
    Plant cell reports 17 (1998), S. 159-164 
    Details
    ISSN: 1432-203X
    Keywords: Key words Cucumber ; Transformation ; Agrobacterium tumefaciens ; Chitinase ; Botrytis cinerea ; Disease resistance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A rice chitinase cDNA (RCC2) driven by the CaMV 35S promoter was introduced into cucumber (Cucumis sativus L.) through Agrobacterium mediation. More than 200 putative transgenic shoots were regenerated and grown on MS medium supplemented with 100 mg/l kanamycin. Sixty elongated shoots were examined for the presence of the integrated RCC2 gene and subsequently confirmed to have it. Of these, 20 were tested for resistance against gray mold (Botrytis cinerea) by infection with the conidia: 15 strains out of the 20 independent shoots exhibited a higher resistance than the control (non-transgenic plants). Three transgenic cucumber strains (designated CR29, CR32 and CR33) showed the highest resistance against B. cinerea: the spread of disease was inhibited completely in these strains. Chitinase gene expression in highly resistant transgenic strains (CR32 and CR33) was compared to that of a susceptible transgenic strain (CR20) and a control. Different responses for disease resistance were observed among the highly resistant strains. CR33 inhibited appressoria formation and penetration of hyphae. Although CR32 permitted penetration of hyphae, invasion of the infection hyphae was restricted. Furthermore, progenies of CR32 showed a segregation ratio of 3:1 (resistant:susceptible). As the disease resistance against gray mold was confirmed to be inheritable, these highly resistant transgenic cucumber strains would serve as good breeding materials for disease resistance.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002990050371
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Optimal design of piezoelectric microstructures (1997)
    Springer
    Computational mechanics 19 (1997), S. 397-410 
    Details
    ISSN: 1432-0924
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Application of piezoelectric materials requires an improvement in their performance characteristics which can be obtained by designing new topologies of microstructures (or unit cells) for these materials. The topology of the unit cell (and the properties of its constituents) determines the effective properties of the piezocomposite. By changing the unit cell topology, better performance characteristics can be obtained in the piezocomposite. Based on this idea, we have proposed in this work an optimal design method of piezocomposite microstructures using topology optimization techniques and homogenization theory. The topology optimization method consists of finding the distribution of material phase and void phase in a periodic unit cell, that optimizes the performance characteristics, subject to constraints such as property symmetry and stiffness. The optimization procedure is implemented using sequential linear programming. In order to calculate the effective properties of a unit cell with complex topology, a general homogenization method applied to piezoelectricity was implemented using the finite element method. This method has no limitations regarding volume fraction or shape of the composite constituents. Although only two-dimensional plane strain topologies of microstructures have been considered to show the implementation of the method, this can be extended to three-dimensional topologies. Microstructures obtained show a large improvement in performance characteristics compared to pure piezoelectric material or simple designs of piezocomposite unit cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004660050188
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Digital image-based modeling applied to the homogenization analysis of composite materials (1997)
    Springer
    Computational mechanics 20 (1997), S. 331-346 
    Details
    ISSN: 1432-0924
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Absract The systematic methodologies to derive accurate microstructural models are developed for studying the mechanical behaviors of composite materials. Since the geometric information of a microstructure is often given by an image or a set of images, the direct interpretation of the geometry is possibly by digitizing it. By identifying each pixel or voxel with a finite element (FE) and accompanying appropriate image processing, an FE model can be automatically generated. It is also emphasized that the digitized models can be suitable for solving the FE equations by utilizing the uniformity of the FE mesh. The finite element analysis (FEA) with the homogenization method enables the prediction the thermo-mechanical behavior of the periodic microstructure (unit cell) as well as the global mechanical response of a structural component, while we are taking into account the specific effect of the geometric structural configuration of the microstructure through digitization. Several kinds of the digitizing techniques are presented to illustrate the potential of digital image-based (DIB) FE modeling of the unit cell. Keeping the microstructural design in mind, the modification of the plane image is introduced and the virtual realization of the unit cell geometry is presented so that a microstructural analysis utilizing the homogenization method would be realistic.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004660050255
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Macro and micro scale modeling of thermal residual stresses in metal matrix composite surface layers by the homogenization method (1997)
    Springer
    Computational mechanics 19 (1997), S. 188-202 
    Details
    ISSN: 1432-0924
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The modeling of thermal residual stresses generated in TaC/stellite and TiC/stellite composite surface layers produced by the oscillating electron beam remelting on low alloys steel is presented. The homogenization method is applied to analyze the real composite microstructures by utilizing the digital image-based (DIB) geometric modeling technique. Two scales of elastic stress analysis are studied: macroscopic one referring to the global structure of composite layer produced over the substrate of low alloy steel and microscopic, comprising the selected unit cell of composite microstructure. The results of the analysis show the microscopic stress to be few times higher than the macroscopic one with stress level much above the elastic limit of matrix material, which implies the development of plastic field around the inclusions. The ceramic inclusions within the unit cell are found to be under high compressive stresses. Also, the composite surface layer stays in compression, mainly by the influence of the stress component parallel to the layer/substrate interface. The effect of hardphase volume fraction is examined and it is found that for a small volume fractions the macro and micro stress does not differ substantially between composites with TaC and TiC hardphases despite their mismatch in thermophysical properties. Also, the stress modeling is presented for the composite containing other inclusions and the problem of the selection between 2D and 3D model for the stress analysis is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004660050168
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...