7,755 research outputs found
Information Technology and Competitive Advantage: The Role of the Ownership Structure
This paper analyses the relationship between information technology use (IT) and competitive advantage. Previous empirical research shows that IT improves competitive advantage when it acts together with some human or managerial resources of an intangible nature. In this work we propose a new complementary resource to IT: democratic ownership structure. We empirically analyse whether ownership structure and IT have a positive, combined impact on competitive advantage. Results show that ownership structure is a key element in explaining competitive advantage differences. Nonetheless, we did not find any IT-ownership structure complementary effect
High bubble concentrations produced by ultrasounds in binary mixtures
7th Meeting of the European‐Society‐of‐Sonochemistry, BIARRITZ GUETHARY, FRANCE, MAY 14‐18, 2000International audienceIt was discovered that simultaneous insonification and air blowing of different aqueous binary solutions such as water/sodium‐dodecyl‐sulphate (SDS), water/methanol or water/potassium‐sulphate yields a very concentrated bubble cloud invading the whole vessel in a few seconds. After the end of insonification, this cloudiness remained in the solution for about 1 min. The phenomenon was investigated by computer‐treatment of solution pictures recorded every second after the end of insonification. Turbidity appeared to increase with ultrasound power, and also with SDS concentration. During the disappearance of the cloud, a turbidity front appeared rising and spreading upward. This front was studied in the characteristic plane and interpreted as a spatial segregation of different bubble sizes rising with different terminal velocities. The bubble sizes involved were estimated to about 10 mum. Adsorption of surface active species are invoked to explain the cloud formation and its abnormally slow disappearance, but the occurrence of the phenomenon for potassium‐sulphate salt remains unexplained
Researchers' Seedbeds for the Development of Research Skills in Universities
The objective of this study is to demonstrate the effects of the application of the pedagogical strategy "researcher's seedbed" in the development of research skills in universities. This research is of quasi-experimental, longitudinal and prospective design, where 2 groups were formed: control and experimental, of 18 students each. A validated instrument was used to measure the research competences, as well as a rubric for the evaluation of the research projects. It began with a pre-test, and after 14 weeks of the development of the strategy, through different educational sessions, the post-test was administered. Likewise, the research projects carried out were evaluated. The results obtained showed that the pedagogical strategy had a positive effect on the development of research skills, with the highest evaluation being found in 40% of the students, with statistically significant differences between the control and experimental groups (Mann Whitney U, p=0.007), and between the pre-test and post-test (Wilcoxon, p=0.00). In the development of cognitive and procedural competence, an effect was also found in the strategy, but not in the attitudinal competence (Mann Whitney U, p=0.496). The application of this study is based on the fact that the formation of research groups in universities strengthens formative research in higher level students. This study shows the benefits of the implementation of strategies for the development of research competencies, since the product will be to train professionals with a scientific culture in favor of society
Evaluating the Effects of Combined Total Ionizing Dose Radiation and Electromagnetic Interference
Although measurement methods for Electromagnetic (EM) immunity and Total Ionizing Dose (TID) radiation are highly standardized, no effort has been made to evaluate the behavior of embedded systems under the combined effects. Considering realistic environment conditions only the measurement of these effects can guarantee reliable embedded systems for critical applications. A configurable platform to evaluate the effects of TID radiation and EM Interference (EMI) on embedded systems is presented. Experiments illustrate the consequences regarding delay and fault occurrence probability as well as current consumption and minimum power supply.Fil: Benfica, Juliano. Pontificia Universidade Católica do Rio Grande do Sul; BrasilFil: Poehls, Leticia M. Bolzani. Pontificia Universidade Católica do Rio Grande do Sul; BrasilFil: Vargas, Fabian. Pontificia Universidade Católica do Rio Grande do Sul; BrasilFil: Lipovetzky, José. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; ArgentinaFil: Lutenberg, Ariel. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: García, Sebastián E.. Universidad de Buenos Aires; ArgentinaFil: Gatti, Edmundo. Instituto Nacional de Tecnología Industrial; ArgentinaFil: Hernandez, Fernando. Universidad ORT Uruguay; Urugua
An Investigative, Cooperative Learning Approach for General Chemistry Laboratories
The integration of research and education is an essential component of our university’s teaching philosophy. Recently, we made a curricular revision to facilitate such an approach in the General Chemistry Laboratory, to teach students that investigative approaches are at the core of sciences. The curriculum revision included new interdisciplinary experiments and a research project. Investigative, peer review, and cooperative learning strategies were introduced to enhance student learning and engagement. An environment in which students can analyze results within a laboratory session and reach comprehensive and quantitative conclusions was encouraged.
To assess our results, students completed questionnaires, evaluated their peers and themselves. Instructors evaluated students through written reports, oral presentations, pre- and post test, a practical exam and a final exam. Assessments of the learning outcomes were performed to determine the level of research skills development, the improvement in laboratory techniques, and depth in analysis of concepts. The experimental designs, implementation of results, and comparisons of student performances using traditional approaches are presented
Effects of an increase in Mexican strawberry exports to Canada on the profitability of pro-ducers in Mexico
Objective: determine the viability of increasing the exported quantity of Mexican strawberries to the Canadian market.
Design/methodology/approach: Likewise, a simulated scenario was developed with the purpose of carrying out a forecast on the conditions that may occur to have a more accurate knowledge of the operation of the international strawberry trade between Mexico and Canada. To perform this analysis, the international market was represented in a partial equilibrium model.
Results: According to the calculated price flexibility, an increase in the exported quantity of Mexican strawberries to Canada of 50% in one year would cause a positive final effect. With this estimate, it can be established that an increase in the exported quantity of Mexican strawberries to Canada of 50% in one year would be viable in the economic sense. In this simulated scenario, the Benefit/Cost Ratio (B/C R) calculated for the producers of Michoacan, Baja California and Guanajuato would be 1.0865, 1.196 and 0.6856 respectively.
Limitations on study/implications: not all products and all states of Mexico are examined.
Findings/conclusions: The results showed that an increase in strawberry production to export to Canada in Michoacan and Baja California would be profitable for the producer, while an increase in strawberry production for export to the Canadian market in Guanajuato would further decrease profitability
The Effects of an Adaptive and Distributed Transmission Power Control on the Performance of Energy Harvesting Sensor Networks
The design of routing protocols for wireless sensor networks (WSNs) has been traditionally tackled by assuming battery-powered sensors, in which minimizing the power consumption was the main objective. Advances in technology and the ability to harvest energy from the environment has enabled self-sustaining systems and thus diminish the significance of network lifetime considerations in the design of WSNs. Although WSNs operated by energy-harvesting sensors are not limited by network lifetime, they still pose new design challenges due to the unstable and uncertain amount of energy that can be harvested from the environment. In this paper, we propose a new protocol for energy-harvesting sensor networks that uses adaptive transmission power to maintain the network connectivity, and distributes the traffic load on the network. Based on local information, each node dynamically adjusts its transmission power in order to maximize the network’s end-to-end performance. The simulation results indicate that the proposed protocol keeps the network connected at most of the times by using an efficient power management, outperforming greedy forwarding and dynamic duty cycle protocols in terms of packet delivery ratio, delay, and power management
Critical analysis of the influence of transnational capitalism on institutions and organizations
This paper aims to analyze the development of capitalism and its influences on institutions and organizations from its beginnings to reach the highest stage in the processes of neoliberal economic globalization and the New Economy version with support of information and communication technologies. In raising this development from a critical analysis, it examines the impacts and effects on individuals, communities and the nation state. Subsequently it is questioned the scope of the imposed transnational neoliberal capitalism model. Finally, it is concluded that it needs a cultural transformation for not accepting the forms of domination, power and alignment of globalizing capitalism and to reconstruct the identity of communities through individual action and asserting collective self-determination, independence and self-management
Local helioseismology of sunspot regions: comparison of ring-diagram and time-distance results
Local helioseismology provides unique information about the subsurface
structure and dynamics of sunspots and active regions. However, because of
complexity of sunspot regions local helioseismology diagnostics require careful
analysis of systematic uncertainties and physical interpretation of the
inversion results. We present new results of comparison of the ring-diagram
analysis and time-distance helioseismology for active region NOAA 9787, for
which a previous comparison showed significant differences in the subsurface
sound-speed structure, and discuss systematic uncertainties of the measurements
and inversions. Our results show that both the ring-diagram and time-distance
techniques give qualitatively similar results, revealing a characteristic
two-layer seismic sound-speed structure consistent with the results for other
active regions. However, a quantitative comparison of the inversion results is
not straightforward. It must take into account differences in the sensitivity,
spatial resolution and the averaging kernels. In particular, because of the
acoustic power suppression, the contribution of the sunspot seismic structure
to the ring-diagram signal can be substantially reduced. We show that taking
into account this effect reduces the difference in the depth of transition
between the negative and positive sound-speed variations inferred by these
methods. Further detailed analysis of the sensitivity, resolution and averaging
properties of the local helioseismology methods is necessary for consolidation
of the inversion results. It seems to be important that both methods indicate
that the seismic structure of sunspots is rather deep and extends to at least
20 Mm below the surface, putting constraints on theoretical models of sunspots.Comment: 10 pages, 10 figures, submitted to Journal of Physics: Conference
Series (JPCS) GONG 2010 - SoHO 24 "A new era of seismology of the Sun and
solar-like stars", June 27 - July 2, 2010 Aix-en-Provence, Franc
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