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排序方式: 共有451条查询结果,搜索用时 15 毫秒
31.
Dr.-Ing. Dipl.-Wirt. Ing. Michael Friedewald Dr. rer. pol. Knut Blind Dr. rer. pol. Jakob Edler 《WIRTSCHAFTSINFORMATIK》2002,44(2):151-161
In this article we present the results of two empirical studies focusing on the structure and extent of the innovation activities of the German Software Industry and analyze distinctive features of Software Innovations. We distinguish the activities of the primary (core) Software Industry and secondary industries such as Mechanical and Electrical Engineering, Motor Industry and Telecommunications. A special focus is put on the question if innovations in Software are sequential, on the role of Open Source Software and the importance of interoperability. 相似文献
32.
Hans Erik Vatne PhD Roar Ørsund PhD Knut Marthinsen PhD Erik Nes 《Metallurgical and Materials Transactions A》1996,27(12):4133-4144
A physically based model for the evolution of recrystallization microstructures and textures during hot rolling of aluminum
is presented. The approach taken differs from similar models developed for steels. The present model is based on recent experimental
investigations directed toward identifying the nature of the nucleation sites for recrystallized grains of different crystallographic
orientations. Particle stimulated nucleation (PSN) and nucleation from cube bands and grain boundary regions have been incorporated
in the model. The multipass aspect complicates the modeling due to partial recrystallization between the rolling passes. Two
different approaches have been suggested to handle this. The model has been applied to predictions of recrystallization kinetics,
recrystallized grain sizes, and recrystallization textures during multipass hot rolling of aluminum. The predictions are reasonable
compared to experimental results. 相似文献
33.
The potentiation of masculine copulatory behavior in castrated male rats following systemic parachlorophenylalanine (PCPA) treatment was found to be dependent upon the strain of rat and the recency of castration. Wistar (W) and Sprague-Dawley (SD) males displayed a decline in behavioral responsiveness to PCPA treatment following castration, the Ws retaining their behavioral responsiveness longer than SDs. Castrated Ws were also behaviorally more responsive to androgen replacement than were SDs. Ovariectomized W and SD females receiving estrogen replacement displayed a strain difference in hormonal sensitivity. In tests for feminine copulatory behavior, ovariectomized Ws were behaviorally more sensitive to estrogen treatment than SDs. Ovariectomized and estrogen-primed females of both strains displayed potentiated lordotic behavior following chronic PCPA treatment. Concomitant treatment with dexamethasone to reduce adrenal steroid output abolished the potentiation of lordotic behavior found with PCPA treatment. (47 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
35.
The paper describes the present state-of-the-art in analyses of ship vibration and elaborates on the difficulties regarding the finite element modelling.Some suggestions to enable better modelling of the structure, dependent on the aims of the analyses, the accuracy of input data, time and cost are given.It is shown that the main resonant frequencies of global and local structures may be predicted with sufficient accuracy, and a good indication of the forced response level may be obtained at the design stage. 相似文献
36.
Zusammenfassung Vergleichend-anatomische Untersuchungen des Holzes vonPopulus Simonii undPopulus robusta ergaben, da? die besten Unterscheidungsmerkmale für diese beiden Pappelarten Unterschiede in den Markstrahlh?hen und im Reichtum
an Strangparenchym sind. Auf Grund der vergleichend-physikalischen Untersuchung wird das Holz vonP. robusta als “ziemlich schwer”, das Holz vonP. Simonii als “mittelschwer” befunden. BeiP. Simonii besteht au?erdem eine Beziehung zwischen Rohwichte und Raumschwindung. Die Schwindung im Splint der Balsampappel ist wesentlich
geringer als diejenige beiP. robusta.
Comparative study on the anatomical and physical properties of wood ofPopulus Simonii andPopulus robusta
Summary Comparative anatomical studies on the wood of Populus Simonii and Populus robusta proved that their differences in ray height and richness in parenchyma are the most reliable characteristics for the distinction of these two poplar species. According to the results of comparative physical investigations the wood of P. robusta is designated as “rather heavy”, the wood of P. Simonii is found to be of “medium weight”. In the case of P. Simonii there is also a relationship between density and volume shrinkage. The shrinkage in the sapwood of balsam-poplar is considerably less than that of P. robusta.相似文献
37.
Die Auswirkungen des Querdrucks auf die Größe der Umformung nichtzug - und zugbeanspruchter Drähte werden theoretisch eingegrenzt, versuchsmäßig untermauert und graphisch dargestellt. Die Querpressung wird von Drähten gleicher Art ausgeübt. Die Einflüsse des Querdruckes aus der Verseilung auf das Tragverhalten eines vollverschlossenen Spiralseiles werden anhand eines Beispieles diskutiert. 相似文献
38.
Einordnung der freien ?stehenden“ Zugelemente aus Drähten zwischen Förderseilen und Spanngliedern, die Beanspruchungen der Zugelemente, ihre Konstruktionsart und ihr Tragverhalten, aus welchen sich die Anforderungen an den einzelnen Draht herleiten lassen. 相似文献
39.
Knut Hanisch 《国际钢铁研究》1980,51(9):367-370
Die Emissionsspektralanalyse eignet sich für die Drahtanalyse, wenn die Anregungsparameter optimiert werden. Es ist erforderlich, den Walzzunder durch Beizen oder mechanische Entzunderung zu entfernen. Die Eichung kann mit amtlichen Spektrometerproben erfolgen. Für alle Proben mit einem Durchmesser größer als 4 mm können die gleichen Eichkurven verwendet werden. Für geseigerte Proben wird eine besondere Probenvorbereitung vorgeschlagen. 相似文献
40.
This paper examines how energy efficiency fails in the building industry based on many years of research into the integration of energy efficiency in the construction of buildings and sustainable architecture in Norway. It argues that energy-efficient construction has been seriously restrained by three interrelated problems: (1) deficiencies in public policy to stimulate energy efficiency, (2) limited governmental efforts to regulate the building industry, and (3) a conservative building industry. The paper concludes that innovation and implementation of new, energy-efficient technologies in the building industry requires new policies, better regulations and reformed practices in the industry itself. 相似文献