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排序方式: 共有1377条查询结果,搜索用时 46 毫秒
31.
Massimo Mecella Barbara Pernici 《The VLDB Journal The International Journal on Very Large Data Bases》2001,10(1):2-15
Component-based approaches are becoming more and more popular to support Internet-based application development. Different
component modeling approaches, however, can be adopted, obtaining different abstraction levels (either conceptual or operational).
In this paper we present a component-based architecture for the design of e-applications, and discuss the concept of wrapper
components as building blocks for the development of e-services, where these services are based on legacy systems. We discuss
their characteristics and their applicability in Internet-based application development.
Received: 30 October 2000 / Accepted: 9 January 2001 Published online: 28 June 2001 相似文献
32.
The main goal of this paper is to show how relatively minor modifications of well-known algorithms (in particular, back propagation) can dramatically increase the performance of an artificial neural network (ANN) for time series prediction. We denote our proposed sets of modifications as the 'self-momentum', 'Freud' and 'Jung' rules. In our opinion, they provide an example of an alternative approach to the design of learning strategies for ANNs, one that focuses on basic mathematical conceptualization rather than on formalism and demonstration. The complexity of actual prediction problems makes it necessary to experiment with modelling possibilities whose inherent mathematical properties are often not well understood yet. The problem of time series prediction in stock markets is a case in point. It is well known that asset price dynamics in financial markets are difficult to trace, let alone to predict with an operationally interesting degree of accuracy. We therefore take financial prediction as a meaningful test bed for the validation of our techniques. We discuss in some detail both the theoretical underpinnings of the technique and our case study about financial prediction, finding encouraging evidence that supports the theoretical and operational viability of our new ANN specifications. Ours is clearly only a preliminary step. Further developments of ANN architectures with more and more sophisticated 'learning to learn' characteristics are now under study and test. 相似文献
33.
Multimodal support to group dynamics 总被引:1,自引:1,他引:0
Fabio Pianesi Massimo Zancanaro Elena Not Chiara Leonardi Vera Falcon Bruno Lepri 《Personal and Ubiquitous Computing》2008,12(3):181-195
The complexity of group dynamics occurring in small group interactions often hinders the performance of teams. The availability
of rich multimodal information about what is going on during the meeting makes it possible to explore the possibility of providing
support to dysfunctional teams from facilitation to training sessions addressing both the individuals and the group as a whole.
A necessary step in this direction is that of capturing and understanding group dynamics. In this paper, we discuss a particular
scenario, in which meeting participants receive multimedia feedback on their relational behaviour, as a first step towards
increasing self-awareness. We describe the background and the motivation for a coding scheme for annotating meeting recordings
partially inspired by the Bales’ Interaction Process Analysis. This coding scheme was aimed at identifying suitable observable
behavioural sequences. The study is complemented with an experimental investigation on the acceptability of such a service.
相似文献
Fabio Pianesi (Corresponding author)Email: |
Massimo ZancanaroEmail: |
Elena NotEmail: |
Chiara LeonardiEmail: |
Vera FalconEmail: |
Bruno LepriEmail: |
34.
Massimo De Santo Gennaro Percannella Carlo Sansone Mario Vento 《Pattern Analysis & Applications》2007,10(2):135-145
In this paper, we propose an innovative architecture to segment a news video into the so-called “stories” by both using the
included video and audio information. Segmentation of news into stories is one of the key issues for achieving efficient treatment
of news-based digital libraries. While the relevance of this research problem is widely recognized in the scientific community,
we are in presence of a few established solutions in the field. In our approach, the segmentation is performed in two steps:
first, shots are classified by combining three different anchor shot detection algorithms using video information only. Then,
the shot classification is improved by using a novel anchor shot detection method based on features extracted from the audio
track. Tests on a large database confirm that the proposed system outperforms each single video-based method as well as their
combination.
相似文献
Mario VentoEmail: |
35.
Felice Strollo Lia Pecorelli Giovanna Strollo Massimo Morè Giuseppe Riondino Maria Angela Masini Bianca Maria Uva 《Microgravity science and technology》2006,18(3-4):226-229
A significant reversible decrease in testosterone (T) has been associated with microgravity in male rodents and humans. Urinary T excretion increases in primates under hypergravity. Hypogonadism is somehow related to abnormally high levels of leptin (L), a hormone produced by the adipose tissue which has been found to increase under microgravity simulation conditions like head down bed rest (HDBR). The aim of this study was to assess hemodynamic and pituitary-adrenal and -gonadal adaptation to an acute HDBR test to be eventually used on a routine basis to get better prepared to next space flights. The Authors performed a 1 hour ?12° HDBR in 6 male and 6 female volunteers who underwent heart rate and blood pressure measurement together with a blood draw three times at 30 min intervals from the start to the end of the test for L, T, estradiol (E2), LH, androstenedione (A), cortisol (F), ACTH. 12 age- and sexmatched control subjects followed the same protocol except for keeping the sitting position all the time. According to the ANOVA for repeated measures, no changes occurred in L, T, E2 or LH whereas A, F and ACTH significantly decreased independently of gender. During HDBR systolic blood pressure decreased in both genders, diastolic blood pressure decreased significantly only in men and HR showed a more clear-cut decrease in women than in men. As a conclusion, such an acute steep-slope HDBR protocol may be efficiently used to testing immediate individual haemodynamic or adrenal response to microgravity but is not suitable for studies concerning gonadal adaptation. 相似文献
36.
Marco Aste Massimo Rossi Roldano Cattoni Bruno Caprile 《Machine Vision and Applications》1998,11(1):16-23
Low-cost, purely visual modules are presented, which are able to reliably perform real-time computation of kinematic quantities
relevant for the navigation of commercial vehicles moving along highways or motorways. Taking as input a video stream of b/w
images coming from a standard camera mounted aboard the vehicle, the modules return instantaneous measurements for the speed
of the vehicle, its lateral position in the lane, and the distance from the preceding vehicle. The modules, which are designed
to work in real-time on standard PC platforms, have been tested under typical working conditions. Preliminary results are
reported and discussed.
Received: 10 March 1997 / Accepted: 24 November 1997 相似文献
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39.
Debora Giordano Francesca Vanara Amedeo Reyneri Massimo Blandino 《International Journal of Food Science & Technology》2016,51(11):2468-2473
Maize germ is a by‐product of the maize milling process that is characterised by a high nutritional value. Currently, heat treatments are employed to prevent full‐fat maize germ from spoilage. The aim of this research was to study the effect of five dry‐heat treatments on the nutritional value of full‐fat maize germ. The results confirmed that after each dry‐heat treatment, the lipase activity decreases but the use of high temperatures could be detrimental for phytosterol and thiamine concentrations. The main negative effects have been observed after treatments at 140 °C for 30 min and 160 °C for 10 min. No significant difference has been observed for protein, ash or fatty acid contents. The treatment at 140 °C for 20 min resulted an optimal combination between temperature and heating time to inactivate lipase without altering deeply the nutritional value and the colour of maize germ. 相似文献
40.
Renato Colle Giuseppe Grosso Alberto Ronzani Massimo Gazzano Vincenzo Palermo 《Carbon》2012,50(3):1332-1337
We describe the self-assembly of soluble, chemically modified fullerene [6,6]-phenyl C61 butyric acid methyl ester (PCBM) into a new crystalline phase where the C60 moieties are arranged in parallel layers. Minimum C60 center-to-center distance is 10 Å within the layers, and up to 15 Å perpendicular to the layers. Highly anisotropic, mesoscopic hexagonal crystals of this material, with a lateral size of many microns and a thickness below 1 μm, are obtained from chloroform solution by solvent vapor annealing, and characterized by optical microscopy and X-ray diffraction. The crystalline structure is deduced combining experimental data with molecular modeling and ab initio calculations. The large difference in C60–C60 spacing indicates a high anisotropy in electrical and charge transport properties of this new phase. 相似文献