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51.
Maria Helena L.B. Braz Sean W.M. SiqueiraDiva de S. e S. Rodrigues Rubens N. Melo 《Computers in human behavior》2011,27(4):1344-1351
The development of instructional content using Information Technologies is an expensive, time-consuming and complex process that requires new methodologies. It was in this context that the concept of Learning Objects (LOs) was proposed in order to promote reuse. However, this goal is not yet fully attained and new contributions to increase reuse are still welcome. Besides, if content is conveyed in LOs that are easier to reuse, they must be combined and sequenced in order to build more elaborated and complex content. This paper presents a strategy to deal with these problems based on the definition of small LOs here called Component Objects (COs). These COs are structured and combined according to a conceptual metamodel, which is the basis for the definition of conceptual schemas representing the existing material, including not only content but also practice. This strategy for searching, extracting, and sequencing COs, supports a teacher to better control the implementation of complex content, reducing errors in the authoring process. This approach includes a specification language and an algorithm for semi-automatic sequencing learning content and practice. Finally, a case study that shows the proposed approach and some results of using the algorithm are presented. 相似文献
52.
Ney Sodr Pablo Guillermo Gonzales-Ormeo Helena Maria Petrilli Cludio Geraldo Schn 《Calphad》2009,33(3):576-583
The metastable phase diagram of the BCC-based ordering equilibria in the Fe–Al–Mo system has been calculated via a truncated cluster expansion, through the combination of Full-Potential-Linear augmented Plane Wave (FP-LAPW) electronic structure calculations and of Cluster Variation Method (CVM) thermodynamic calculations in the irregular tetrahedron approximation. Four isothermal sections at 1750 K, 2000 K, 2250 K and 2500 K are calculated and correlated with recently published experimental data on the system. The results confirm that the critical temperature for the order–disorder equilibrium between Fe3Al–D03 and FeAl–B2 is increased by Mo additions, while the critical temperature for the FeAl–B2/A2 equilibrium is kept approximately invariant with increasing Mo contents. The stabilization of the Al-rich A2 phase in equilibrium with overstoichiometric B2–(Fe,Mo)Al is also consistent with the attribution of the A2 structure to the τ2 phase, stable at high temperatures in overstoichiometric B2–FeAl. 相似文献
53.
54.
Mobile Virtual Reality provides a gateway for marketers to innovatively reach consumers. This study examines the impact of Virtual Reality in the context of transformational brand experience appeals, focussing specifically on the determining role of vividness. A three-dimensional conceptual framework is presented, offering a systematic review of the literature on vividness effects in marketing communications, revealing the major gap that most available studies only focus on informational messages. We conducted an experiment to address this gap and demonstrate in the context of a transformational ad that Virtual Reality generates higher perceptions of vividness and presence than a regular two-dimensional video, with vividness positively affecting attitude toward the ad, both directly and indirectly via presence. Our study also reveals that vividness in turn elicits a positive effect on brand attitudes which stimulates consumers’ purchase intentions. As such, the strategic potential of Virtual Reality for marketing communications is highlighted. 相似文献
55.
Armando Carravetta Giuseppe Del Giudice Oreste Fecarotta Helena M. Ramos 《Water Resources Management》2012,26(13):3947-3959
Pump operating as turbine (PAT) is an effective source of reducing the equipment cost in small hydropower plants. However, the manufacturers provide poor information on the PAT performance thus representing a limit for its wider diffusion. Additional implementation difficulties arise under variable operating conditions, characteristic of water distribution networks (WDNs). WDNs allow to obtain widespread and globally significant amount of produced energy by exploiting the head drop due to the network pressure control strategy for leak reductions. Thus a design procedure is proposed that couples a parallel hydraulic circuit with an overall plant efficiency criteria for the market pump selection within a WDN. The proposed design method allows to identify the performance curves of the PAT that maximizes the produced energy for an assigned flow and pressure-head distribution pattern. Finally, computational fluid dynamics (CFD) is shown as a suitable alternative for performance curve assessment covering the limited number of experimental data. 相似文献
56.
Previous research has shown loneliness as a threat for the quality of life of older people; therefore the goal of the intervention in a quasi-experimental study was to evaluate and discuss the self-reported level of loneliness of older people in Finland and Slovenia before and after a computer intervention. Intervention in a quasi-experimental study was conducted among 58 older participants at the baseline (M = 72.4 years) and 45 older participants at the follow-up research study (M = 72.9 years). Inferential statistics showed a significant difference in the reduction of loneliness between the countries, and a decreased level of loneliness of older people after completing the computer training course. Although older people experience many age-related problems which may reduce their interest in learning information and communication technology (ICT) skills, it is important that they are computer-proficient, because computer engagement can reduce the level of loneliness of older people and in this way has a positive effect on their quality of life. 相似文献
57.
We review, unify and extend work pertaining to evaluating mode mixity of interfacial fracture utilizing the virtual crack
closure technique (VCCT). From the VCCT, components of the strain energy release rate (SERR) are obtained using the forces
and displacements near the crack tip corresponding to the opening and sliding contributions. Unfortunately, these components
depend on the crack extension size, Δ, used in the VCCT. It follows that a mode mixity based upon these components also will
depend on the crack extension size. However, the components of the strain energy release rate can be used for determining
the complex stress intensity factors (SIFs) and the associated mode mixity. In this study, we show that several—seemingly
different—suggested methods presented in the literature used to obtain mode mixity based on the stress intensity factors are
indeed identical. We also present an alternative, simpler quadratic equation to this end. Moreover, a Δ-independent strain
energy release based mode mixity can be defined by introducing a “normalizing length parameter.” We show that when the reference
length (used for the SIF-based mode mixity) and the normalizing length (used for Δ-independent SERR-based mode mixity) are
equal, the two mode mixities are only shifted by a phase angle, depending on the bimaterial parameter ε. 相似文献
58.
Franko Debra L.; Striegel-Moore Ruth H.; Bean Judy; Tamer Robert; Kraemer Helena C.; Dohm Faith-Anne; Crawford Patricia B.; Schreiber George; Daniels Stephen R. 《Canadian Metallurgical Quarterly》2005,24(6):586
Depression in adolescent girls may result in negative consequences in young adulthood. The Center for Epidemiologic Studies Depression Scale (CES-D) was administered to 1,727 Black and White girls ages 16 to 18 years who participated in the National Heart, Lung, and Blood Institute's Growth and Health Study. Three years later, women in the depressed groups were more likely to be current smokers, had attained a lower level of education, and reported lower self-worth relative to the nondepressed group. Body dissatisfaction, eating concerns, and loneliness were greater in the depressed groups. Relative to Black women, White women who were moderately depressed during adolescence reported more health care services utilization in young adulthood. Prevention efforts for depressed adolescents should be broadly focused to improve young adult outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
This article describes an evaluation of six different methods for prioritizing software requirements. Based on the quality requirements for a telephony system, the authors individually used all six methods on separate occasions to prioritize the requirements. The methods were then characterized according to a number of criteria from a user's perspective. We found the analytic hierarchy process to be the most promising method, although it may be problematic to scale-up. In an industrial follow-up study we used the analytic hierarchy process to further investigate its applicability. We found that the process is demanding but worth the effort because of its ability to provide reliable results, promote knowledge transfer and create consensus among project members. 相似文献
60.
An efficient, accurate and practical process for prioritising requirements is of great importance in commercial software developments.
This article improves an existing cost-value approach in which stakeholders compare all unique pairs of candidate requirements
according to their value and their cost of implementation. Techniques for reducing the required number of comparisons are
suggested, thus making the process more efficient. An initial approach for managing requirements interdependencies is proposed.
A support tool for the improved process has been developed to make the process more practical in commercial developments.
The improved process and its support tool have been applied and evaluated in an industrial project at Ericsson Radio Systems
AB. The results indicate a pressing need for mature processes for prioritising requirements, and the work presented here is
an important step in that direction. 相似文献