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排序方式: 共有2807条查询结果,搜索用时 15 毫秒
51.
Marco Tarabini Stefano Solbiati Bortolino Saggin Diego Scaccabarozzi 《Ergonomics》2016,59(8):1038-1049
This paper describes the experimental characterisation of the apparent mass matrix of eight male subjects in standing position and the identification of nonlinearities under both mono-axial and dual-axis whole-body vibration. The nonlinear behaviour of the response was studied using the conditioned response techniques considering models of increasing complexity. Results showed that the cross-axis terms are comparable to the diagonal terms. The contribution of the nonlinear effects are minor and can be endorsed to the change of modal parameters during the tests. The nonlinearity generated by the vibration magnitude is more evident in the subject response, since magnitude-dependent effects in the population are overlaid by the scatter in the subjects’ biometric data. The biodynamic response is influenced by the addition of a secondary vibration axis and, in case of dual-axis vibrations, the overall magnitude has a marginal contribution.
Practitioner Summary: We have measured both the diagonal and cross-axis elements of the apparent mass matrix. The effect of nonlinearities and the simultaneous presence of vibration along two axes are smaller than the inter-subject variability. 相似文献
52.
Inspired by recent work on robust and fast computation of 3D Local Reference Frames (LRFs), we propose a novel pipeline for coarse registration of 3D point clouds. Key to the method are: (i) the observation that any two corresponding points endowed with an LRF provide a hypothesis on the rigid motion between two views, (ii) the intuition that feature points can be matched based solely on cues directly derived from the computation of the LRF, (iii) a feature detection approach relying on a saliency criterion which captures the ability to establish an LRF repeatably. Unlike related work in literature, we also propose a comprehensive experimental evaluation based on diverse kinds of data (such as those acquired by laser scanners, Kinect and stereo cameras) as well as on quantitative comparison with respect to other methods. We also address the issue of setting the many parameters that characterize coarse registration pipelines fairly and realistically. The experimental evaluation vouches that our method can handle effectively data acquired by different sensors and is remarkably fast. 相似文献
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Organizational Learning Mechanisms and Creative Climate: Insights from an Italian Fashion Design Company 下载免费PDF全文
Stefano Cirella Filomena Canterino Marco Guerci Abraham B. Shani 《Creativity & Innovation Management》2016,25(2):211-222
This paper investigates the relationship between different types of organizational learning mechanisms and creative climate. In the context of an action research study, this paper focuses on insights from a survey that was administered to all the employees of the Product Design and Development unit of the company. The results demonstrate that the three different types of organizational learning mechanisms considered in the study (cognitive, structural and procedural mechanisms) are associated with creative climate. The study generates new scientific knowledge about the role of organizational learning mechanisms and provides specific recommendations for organizations that aim to enhance creative climate. 相似文献
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Vittorio Ghini Stefano Ferretti Fabio PanzieriAuthor vitae 《Journal of Systems and Software》2011,84(11):1827-1851
This paper presents a distributed architecture for the provision of seamless and responsive mobile multimedia services. This architecture allows its user applications to use concurrently all the wireless network interface cards (NICs) a mobile terminal is equipped with. In particular, as mobile multimedia services are usually implemented using the UDP protocol, our architecture enables the transmission of each UDP datagram through the “most suitable” (e.g. most responsive, least loaded) NIC among those available at the time a datagram is transmitted. We term this operating mode of our architecture Always Best Packet Switching (ABPS). ABPS enables the use of policies for load balancing and recovery purposes. In essence, the architecture we propose consists of the following two principal components: (i) a fixed proxy server, which acts as a relay for the mobile node and enables communications from/to this node regardless of possible firewalls and NAT systems, and (ii) a proxy client running in the mobile node responsible for maintaining a multi-path tunnel, constructed out of all the node's NICs, with the above mentioned fixed proxy server. We show how the architecture supports multimedia applications based on the SIP and RTP/RTCP protocols, and avoids the typical delays introduced by the two way message/response handshake of the SIP signaling protocol. Experimental results originated from the implementation of a VoIP application on top of the architecture we propose show the effectiveness of our approach. 相似文献
58.
Stefano Federici Simonetta Montemagni Vito Pirrelli 《Computers and the Humanities》2000,34(1-2):199-204
The paper describes SENSE, a word sense disambiguation system thatmakes use of different types of cues to infer the most likelysense of a word given its context. Architecture and functioning ofthe system are briefly illustrated. Results are given for theROMANSEVAL Italian test corpus of verbs. 相似文献
59.
Barelli S Canellini G Thadikkaran L Crettaz D Quadroni M Rossier JS Tissot JD Lion N 《Proteomics. Clinical applications》2008,2(2):142-157
Protein oxidation mechanisms result in a wide array of modifications, from backbone cleavage or protein crosslinking to more subtle modifications such as side chain oxidations. Protein oxidation occurs as part of normal regulatory processes, as a defence mechanism against oxidative stress, or as a deleterious processes when antioxidant defences are overcome. Because blood is continually exposed to reactive oxygen and nitrogen species, blood proteomics should inherently adopt redox proteomic strategies. In this review, we recall the biochemical basis of protein oxidation, review the proteomic methodologies applied to analyse redox modifications, and highlight some physiological and in vitro responses to oxidative stress of various blood components. 相似文献
60.
Stefano Tonzani 《Computer Physics Communications》2007,176(2):146-156
FERM3D is a three-dimensional finite element program, for the elastic scattering of a low energy electron from a general polyatomic molecule, which is converted to a potential scattering problem. The code is based on tricubic polynomials in spherical coordinates. The electron-molecule interaction is treated as a sum of three terms: electrostatic, exchange, and polarization. The electrostatic term can be extracted directly from ab initio codes (GAUSSIAN 98 in the work described here), while the exchange term is approximated using a local density functional. A local polarization potential based on density functional theory [C. Lee, W. Yang, R.G. Parr, Phys. Rev. B 37 (1988) 785] describes the long range attraction to the molecular target induced by the scattering electron. Photoionization calculations are also possible and illustrated in the present work. The generality and simplicity of the approach is important in extending electron-scattering calculations to more complex targets than it is possible with other methods.
Program summary
Title of program:FERM3DCatalogue identifier:ADYL_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADYL_v1_0Program obtainable from: CPC Program Library, Queen's University of Belfast, N. IrelandComputer for which the program is designed and others on which it has been tested:Intel Xeon, AMD Opteron 64 bit, Compaq AlphaOperating systems or monitors under which the program has been tested:HP Tru64 Unix v5.1, Red Hat Linux Enterprise 3Programming language used:Fortran 90Memory required to execute with typical data:900 MB (neutral CO2), 2.3 GB (ionic CO2), 1.4 GB (benzene)No. of bits in a word:32No. of processors used:1Has the code been vectorized?:NoNo. of lines in distributed program, including test data, etc.:58 383No. of bytes in distributed program, including test data, etc.:561 653Distribution format:tar.gzip fileCPC Program library subprograms used:ADDA, ACDPNature of physical problem:Scattering of an electron from a complex polyatomic molecular target.Method of solution:Solution of a partial differential equation using a finite element basis, and direct sparse linear solvers.Restrictions on the complexity of the problem:Memory constraints.Typical running time:2 hours.Unusual features of the program:- •
- very extensive use of memory,
- •
- requires installation of Lapack, Blas, a direct sparse solver library (SuperLU, freely available, or Pardiso, which requires a license, but is free of charge for academic use), and optionally the Cernlib and Arpack libraries, freely available,
- •
- requires input from quantum chemistry programs (Gaussian, Molpro or PC Gamess).