971 resultados para mobile media


Relevância:

20.00% 20.00%

Publicador:

Resumo:

La sèrie d'informes Horizon és el resultat més tangible del Projecte Horizon del New Media Consortium, un esforç de recerca qualitativa iniciat el 2002, que identifica i descriu les tecnologies emergents amb més potencial d'impacte en l'ensenyament, l'aprenentatge, la recerca i la expressió creativa en l'àmbit educatiu global. Aquest volum, Perspectivas tecnológicas: educação superior na Ibero-américa 2012-2017, és la segona edició del Projecte Horizon Iberoamèrica i se centra en la investigació en els països de la regió Iberoamericana (incloent-hi tota Llatinoamèrica, Espanya i Portugal) i en l'àmbit de l'educació superior. Ha estat produït pel NMC i l'eLearn Center de la Universitat Oberta de Catalunya.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Over the last decades, calibration techniques have been widely used to improve the accuracy of robots and machine tools since they only involve software modification instead of changing the design and manufacture of the hardware. Traditionally, there are four steps are required for a calibration, i.e. error modeling, measurement, parameter identification and compensation. The objective of this thesis is to propose a method for the kinematics analysis and error modeling of a newly developed hybrid redundant robot IWR (Intersector Welding Robot), which possesses ten degrees of freedom (DOF) where 6-DOF in parallel and additional 4-DOF in serial. In this article, the problem of kinematics modeling and error modeling of the proposed IWR robot are discussed. Based on the vector arithmetic method, the kinematics model and the sensitivity model of the end-effector subject to the structure parameters is derived and analyzed. The relations between the pose (position and orientation) accuracy and manufacturing tolerances, actuation errors, and connection errors are formulated. Computer simulation is performed to examine the validity and effectiveness of the proposed method.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Data traffic caused by mobile advertising client software when it is communicating with the network server can be a pain point for many application developers who are considering advertising-funded application distribution, since the cost of the data transfer might scare their users away from using the applications. For the thesis project, a simulation environment was built to mimic the real client-server solution for measuring the data transfer over varying types of connections with different usage scenarios. For optimising data transfer, a few general-purpose compressors and XML-specific compressors were tried for compressing the XML data, and a few protocol optimisations were implemented. For optimising the cost, cache usage was improved and pre-loading was enhanced to use free connections to load the data. The data traffic structure and the various optimisations were analysed, and it was found that the cache usage and pre-loading should be enhanced and that the protocol should be changed, with report aggregation and compression using WBXML or gzip.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The objective of this thesis is to shed light on the vertical vibration of granular materials for potential interest in the power generation industry. The main focus is investigating the drag force and frictional resistance that influence the movement of a granular material (in the form of glass beads) contained in a vessel, which is subjected to sinusoidal oscillation. The thesis is divided into three parts: theoretical analysis, experiments and computer simulations. The theoretical part of this study presents the underlying physical phenomena of the vibration of granular materials. Experiments are designed to determine fundamental parameters that contribute to the behavior of vibrating granular media. Numerical simulations include the use of three different software applications: FLUENT, LS-DYNA and ANSYS Workbench. The goal of these simulations is to test theoretical and semiempirical models for granular materials in order to validate their compatibility with the experimental findings, to assist in predicting their behavior, and to estimate quantities that are hard to measure in laboratory.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Streaming potential measurements for the surface charge characterisation of different filter media types and materials were used. The equipment was developed further so that measurements could be taken along the surfaces, and so that tubular membranes could also be measured. The streaming potential proved to be a very useful tool in the charge analysis of both clean and fouled filter media. Adsorption and fouling could be studied, as could flux, as functions of time. A module to determine the membrane potential was also constructed. The results collected from the experiments conducted with these devices were used in the study of the theory of streaming potential as an electrokinetic phenomenon. Several correction factors, which are derived to take into account the surface conductance and the electrokinetic flow in very narrow capillaries, were tested in practice. The surface materials were studied using FTIR and the results compared with those from the streaming potentials. FTIR analysis was also found to be a useful tool in the characterisation of filters, as well as in the fouling studies. Upon examination of the recorded spectra from different depths in a sample it was possible to determine the adsorption sites. The influence of an external electric field on the cross flow microflltration of a binary protein system was investigated using a membrane electroflltration apparatus. The results showed that a significant improvement could be achieved in membrane filtration by using the measured electrochemical properties to help adjust the process conditions.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This thesis introduces a real-time simulation environment based on the multibody simulation approach. The environment consists of components that are used in conventional product development, including computer aided drawing, visualization, dynamic simulation and finite element software architecture, data transfer and haptics. These components are combined to perform as a coupled system on one platform. The environment is used to simulate mobile and industrial machines at different stages of a product life time. Consequently, the demands of the simulated scenarios vary. In this thesis, a real-time simulation environment based on the multibody approach is used to study a reel mechanism of a paper machine and a gantry crane. These case systems are used to demonstrate the usability of the real-time simulation environment for fault detection purposes and in the context of a training simulator. In order to describe the dynamical performance of a mobile or industrial machine, the nonlinear equations of motion must be defined. In this thesis, the dynamical behaviour of machines is modelled using the multibody simulation approach. A multibody system may consist of rigid and flexible bodies which are joined using kinematic joint constraints while force components are used to describe the actuators. The strength of multibody dynamics relies upon its ability to describe nonlinearities arising from wearing of the components, friction, large rotations or contact forces in a systematic manner. For this reason, the interfaces between subsystems such as mechanics, hydraulics and control systems of the mechatronic machine can be defined and analyzed in a straightforward manner.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper proposes the use of an autonomous assistant mobile robot in order to monitor the environmental conditions of a large indoor area and develop an ambient intelligence application. The mobile robot uses single high performance embedded sensors in order to collect and geo-reference environmental information such as ambient temperature, air velocity and orientation and gas concentration. The data collected with the assistant mobile robot is analyzed in order to detect unusual measurements or discrepancies and develop focused corrective ambient actions. This paper shows an example of the measurements performed in a research facility which have enabled the detection and location of an uncomfortable temperature profile inside an office of the research facility. The ambient intelligent application has been developed by performing some localized ambient measurements that have been analyzed in order to propose some ambient actuations to correct the uncomfortable temperature profile.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We present the implementation of dynamic electrostatic force microscopy in liquid media. This implementation enables the quantitative imaging of local dielectric properties of materials in electrolyte solutions with nanoscale spatial resolution. Local imaging capabilities are obtained by probing the frequency-dependent and ionic concentration-dependent electrostatic forces at high frequency (>1 MHz), while quantification of the interaction forces is obtained with finite-element numerical calculations. The results presented open a wide range of possibilities in a number of fields where the dielectric properties of materials need to be probed at the nanoscale and in a liquid environment.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We present the implementation of dynamic electrostatic force microscopy in liquid media. This implementation enables the quantitative imaging of local dielectric properties of materials in electrolyte solutions with nanoscale spatial resolution. Local imaging capabilities are obtained by probing the frequency-dependent and ionic concentration-dependent electrostatic forces at high frequency (>1 MHz), while quantification of the interaction forces is obtained with finite-element numerical calculations. The results presented open a wide range of possibilities in a number of fields where the dielectric properties of materials need to be probed at the nanoscale and in a liquid environment.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We present new analytical tools able to predict the averaged behavior of fronts spreading through self-similar spatial systems starting from reaction-diffusion equations. The averaged speed for these fronts is predicted and compared with the predictions from a more general equation (proposed in a previous work of ours) and simulations. We focus here on two fractals, the Sierpinski gasket (SG) and the Koch curve (KC), for two reasons, i.e. i) they are widely known structures and ii) they are deterministic fractals, so the analytical study of them turns out to be more intuitive. These structures, despite their simplicity, let us observe several characteristics of fractal fronts. Finally, we discuss the usefulness and limitations of our approa

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We deal with a system of prisoner’s dilemma players undergoing continuous motion in a two-dimensional plane. In contrast to previous work, we introduce altruistic punishment after the game. We find punishing only a few of the cooperator-defector interactions is enough to lead the system to a cooperative state in environments where otherwise defection would take over the population. This happens even with soft nonsocial punishment (where both cooperators and defectors punish other players, a behavior observed in many human populations). For high enough mobilities or temptations to defect, low rates of social punishment can no longer avoid the breakdown of cooperation

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Problems in the mobile services are complex where the lack of the user analysis is not the modest issue. User centered design has increasingly become as a basis for the design of mobile services. The concept of user centered design gives end-user extensive attention at each stage of the design process. Mobile service providers want to offer experiences for users and clearly the users look for services that can provide pleasant experiences. In this thesis, the elements of user experience in mobile internet were studied as well as user experience measuring methods were researched. This study was looking for user experience measuring metrics and methods to specify new factors to measure user experience. During this thesis research project an application called CEM4Mobile was designed and implemented. CEM4Mobile is an application for observing and analysing user experience based on the user activity and behaviour. As a result of this thesis, a collection of user experience elements and measuring metrics were found. The elements and metrics were designed and implemented to CEM4Mobile product, which measures user experience. It was found out that the user experience measuring methods were based on interaction between two people but CEM4Mobile makes user observation programmatic.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The problematic use of mobile phones among adolescents has not been widely studied. There are very few instruments for assessing potential technological addiction to mobile phones, or for categorizing different types of users or uses. The most widely used scale is the Mobile Phone Problem Use Scale (MPPUS), which is used to study adult populations, and has been applied in various forms in international contexts. The aims of this study were to adapt the Spanish version of this scale (MPPUSA) to British adolescents, and then to estimate the prevalence of possible problematic users. A questionnaire was administered to a sample of 1,529 secondary school pupils aged between 11 and 18 years, with 1,026 completed questionnaires being collected. The analysis showed that the factor and construct validity and reliability were comparable to those obtained in previous studies. The prevalence of problematic users among the students was 10%, and the typical problematic user tended to be an adolescent between 11 and 14 years old, studying in a public school, who considered themselves to be an expert user of this technology, who made extensive use of his/her mobile phone, and who attributed the same problem of use among their peers. These users presented notable scores in all the symptoms covered by the scale used to assess problematic use. In conclusion, the adaptation of the MPPUSA as a screening scale for British adolescents presents good sensitivity and specificity for detecting the main addictive symptoms proposed in this validated version.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

El uso problemático del teléfono móvil es un fenómeno emergente en nuestra sociedad, que parece afectar especialmente a la población adolescente. El conocimiento acerca del uso problemático de esta tecnología resulta necesario, dado que puede desarrollarse un patrón comportamental con características adictivas. Apenas existen escalas que midan el posible uso problemático del móvil y ninguna adaptada exclusivamente a población adolescente española. La escala más utilizada internacionalmente es la Mobile Phone Problematic Use Scale (MPPUS). El objetivo de este estudio es adaptar el MPPUS a la población adolescente española. Se administró la versión española del cuestionario a una muestra de 1132 de 12 a 18 años. La fiabilidad y la validez factorial eran comparables a las obtenidas en población adulta, por lo que la medida del uso problemático del móvil en los adolescentes españoles es unidimensional. Se detectó una prevalencia del 14.8% de usuarios problemáticos.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This article describes a literature review of the influence of advertising and the media on Eating Disorders (ED). Research published in scientific journals in various fields of social sciences such as sychology, psychiatry and communication science has enabled us to conclude that the content displayed in the media, including advertising, are enhancers of disorders and contribute significantly to body issatisfaction in relation to the perceived idea of beauty, it also facilitates the development of weight loss strategies in women and gain of muscle mass in men.