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101.
The aim of this paper is to present a picture of student experience of a collaborative e-learning module in an asynchronous e-learning environment. A distance learning module on music education worth five credit points for a bachelor online degree for primary school educating teachers was assessed using a self-evaluation questionnaire that gathered quantitative and qualitative data about student satisfaction of the collaborative e-learning activity. The quantitative part of the questionnaire consisted of 27 closed questions on a 10-point Likert scale and offered data about satisfaction with the module. The qualitative part of the questionnaire provided an insight into the participant perspective of the online collaborative experience. General open questions on satisfaction and dissatisfaction were analyzed with an inductive analysis which showed the evaluation criteria used by 92 students. Results of the analysis showed five themes of the participants’ perspectives, which were interpreted by the researcher as: teamwork, cognitive, operating, organizing, and emotive/ethic for the positive aspects and teamwork, operating, organizing, and emotive/ethic for the aspects to be improved. The aspects that were associated with satisfaction include: collaborating, comparing ideas, sharing knowledge and skills to support each other, peer learning, analyzing and integrating different points of view, the usability of the platform, group planning and workload management. Aspects of the student learning experience that should inform the improvements of e-learning include: more collaboration between students since some students engage differently; more coordination and organization, the workload management in the group activities, some technical problems such as updating modifications. The participants’ results in the module increased their didactic potential as primary school teachers. The findings are discussed in relation to their potential impact on developing collaborative activities addressed to teacher education in distance learning. Implications for future research are also considered. 相似文献
102.
Gianluca Bianchi Fasani Francesca Bozzano Michele Cercato 《Bulletin of Engineering Geology and the Environment》2011,70(4):533-542
There are many abandoned underground mines beneath the city of Rome, created in the Pleistocene pyroclastic deposits over
thousands of years. These pose a serious public safety risk hence the study was undertaken to better assess the stability
of the underground workings. The Villa de Sanctis public park was selected as a suitable test site, as in this area the cavity
network can be inspected and the different steps of the progressive migration of voids toward the surface can be identified.
In addition to an underground geological survey, geophysical investigations were undertaken to elucidate some key characteristics
of the involved lithological units, including elastic stiffness and layer thickness. Recommendations are made for further
studies of the accessible and inaccessible areas. 相似文献
103.
A modeling method aimed at eliminating the need of explicit crack representation in bi-dimensional structures is presented
for the simulation of the initiation and subsequent propagation within composite materials. This is achieved by combining
a meshless method with a physical stress–displacement based criterion known as Cohesive Model. This model consents to apply
a penalty-based approach to delamination modeling where a variable penalty factor along the crack segment allows to loosen
or tight the two parts according to their relative displacements. Results are showed for classical single mode loading benchmark
cases and compared to experimental results taken from the literature. 相似文献
104.
Sinico Michele; Parovel Giulia; Casco Clara; Anstis Stuart 《Canadian Metallurgical Quarterly》2009,35(4):948
We show that human observers strongly underestimate a linear or circular trajectory that a luminous spot follows in the dark. At slow speeds, observers are relatively accurate, but, as the speed increases, the size of the path is progressively underestimated, by up to 35%. The underestimation imposes little memory load and does not require tracking of the trajectory. Most importantly, we found that underestimation occurred only when successive motion vectors changed in direction. This suggests a perceptual rather than representational origin of the illusion, related to vector-sum integration over time of neural motion signals in different directions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
Karel Michele J.; Knight Bob G.; Duffy Michael; Hinrichsen Gregory A.; Zeiss Antonette M. 《Canadian Metallurgical Quarterly》2010,4(2):75
Professional geropsychology is a growing area of practice and training. To meet the mental health needs of an aging population, increasing numbers of psychologists need to develop competence to work with older adults, their families, and related care systems. The Pikes Peak model for geropsychology training (Knight, Karel, Hinrichsen, Qualls, & Duffy, 2009) delineates attitude, knowledge, and skill competencies for professional geropsychology practice and makes recommendations for training. In this paper, we define and illustrate the Pikes Peak geropsychology practice competencies through a case example. In the case, an older man with complex needs seeks care through a generalist psychologist in an outpatient setting. The attitudes, knowledge, and skills that the psychologist needs to consider, and implications for training, are reviewed. Training recommendations and resources are provided, with a focus on the training needs of psychologists who wish to expand their practices to include older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
Vujasinovic Marko Ivezic Nenad Kulvatunyou Boonserm Barkmeyer Edward Missikoff Michele Taglino Francesco Marjanovic Zoran Miletic Igor 《Internet Computing, IEEE》2010,14(1):52-63
The authors discuss a semantic-mediation architecture to advance traditional approaches for standards-based business-to-business (B2B) interoperability. The architecture is supported by the Athena Knowledge Representation and Semantics Mediation tool suite. Initial experimentations with the architecture and the toolset offer discussions of key architectural and functional aspects and suggest directions for future tools enhancements. 相似文献
107.
Michele Dei Nicolò Nizza Massimo Piotto Paolo Bruschi 《Analog Integrated Circuits and Signal Processing》2009,58(1):43-47
A compact voltage controlled CMOS current divider is presented. Differently from previous implementations, exploiting the
MOSFET translinear characteristics in subthreshold region, the proposed circuit is based on devices operating from moderate
to strong inversion. An input current linearity range of nearly a decade is obtained by compensating for the deviations from
the ideal drain current square-law approximation through an original empirical approach. The circuit is suitable for use as
a building block in analog multipliers and for transconductor continuous tuning. The effectiveness of the proposed configuration
is demonstrated by means of electrical simulations, performed on a prototype designed with a commercial process. The robustness
of the linearization algorithm with respect to temperature variations is proven. 相似文献
108.
The time reversal of a completely-positive, nonequilibrium discrete-time quantum Markov evolution is derived in a general
framework via a suitable adjointness relation. Space-time harmonic processes are then introduced for the forward and reverse-time
transition mechanisms, and their role in the study of quantum dynamics is illustrated by discussing (operator and scalar)
relative entropy dynamics. 相似文献
109.
De Angelis M Curtin AC McSweeney PL Faccia M Gobbetti M 《The Journal of dairy research》2002,69(2):255-267
A homo-tetrameric approximately 160-kDa cystathionine gamma-lyase was purified to homogeneity from Lactobacillus reuteri DSM 20016 by four chromatographic steps. The activity was pyridoxal-5'-phosphate dependent and the enzyme catalyzed the alpha,gamma-elimination reaction of L-cystathionine, producing L-cysteine, ammonia and alpha-ketobutyrate. The enzyme was active towards a range of amino acids and amino acid derivatives, including methionine. The pH and temperature optima were found to be 8.0 and 35 degrees C. respectively. Isoelectric pH (pI) was approximately 5.0 as determined by two-dimensional electrophoresis. Sensitivity to chemical inhibitors was typical of lactococcal cystathionine gamma- and beta-lyases, except it was inhibited by sulphydryl reagents. The N-terminal sequence was MKFNTQLIHGGNSED, which had 100% homology with cystathionine beta-lyase of Lb. reuteri 104R (Accession Number (CAC05298). Lb. reuteri DSM 20016. together with 10 other strains of non-starter lactic acid bacteria, was used as adjunct starter in the production of miniature ('anestrato Pugliese-like cheeses. After 40 d ripening, the water-soluble extract of the cheeses with added Lactobacillus fermentum DT41 and Lb. reuteri DSM 20016 contained the highest enzyme activities on cystathionine and methionine substrates. Determinations of methanethiol, dimethyl sulphide, dimethyl disulphide and dimethyl trisulphide in the miniature cheeses confirmed the findings of enzyme activities. 相似文献
110.
Sung KB Liang C Descour M Collier T Follen M Richards-Kortum R 《IEEE transactions on bio-medical engineering》2002,49(10):1168-1172
We have built a fiber-optic confocal reflectance microscope capable of imaging human tissues in near real time. Miniaturization of the objective lens and the mechanical components for positioning and axially scanning the objective enables the device to be used in inner organs of the human body. The lateral resolution is 2 micrometers and axial resolution is 10 micrometers. Confocal images of fixed tissue biopsies and the human lip in vivo have been obtained at 15 frames/s without any fluorescent stains. Both cell morphology and tissue architecture can be appreciated from images obtained with this microscope. 相似文献