956 resultados para Direct digital detector
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This paper makes a case for a direct relationship between digital literacy and nonlinear thinking styles, articulates a demand for nonlinear thinking styles in education and the workplace, and states implications for a connection between nonlinear thinking styles visual literacy, and intuitive artistic practice.
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The purpose of this study was to gain a better understanding of the foreign direct investment location decision making process through the examination of non-Western investors and their investment strategies in non-traditional markets. This was accomplished through in-depth personal interviews with 50 Overseas Chinese business owners and executives in several different industries from Hong Kong, Singapore, Taiwan, Malaysia, and Thailand about 97 separate investment projects in Southeast and East Asia, including The Philippines, Malaysia, Hong Kong, Singapore, Vietnam, India, Pakistan, South Korea, Australia, Indonesia, Cambodia, Thailand, Burma, Taiwan, and Mainland China.^ Traditional factors utilized in Western models of the foreign direct investment decision making process are reviewed, as well as literature on Asian management systems and the current state of business practices in emerging countries of Southeast and East Asia. Because of the lack of institutionalization in these markets and the strong influences of Confucian and patriarchal value systems on the Overseas Chinese, it was suspected that while some aspects of Western rational economic models of foreign direct investment are utilized, these models are insufficient in this context, and thus are not fully generalizable to the unique conditions of the Overseas Chinese business network in the region without further modification.^ Thus, other factors based on a Confucian value system need to be integrated into these models. Results from the analysis of structured interviews suggest Overseas Chinese businesses rely more heavily on their network and traditional Confucian values than rational economic factors when making their foreign direct investment location decisions in emerging countries in Asia. This effect is moderated by the firm's industry and the age of the firm's owners. ^
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In an attempt to improve students' functional understanding of plagiarism a variety of approaches were tried within the context of a more comprehensive information literacy program. Sessions were taught as a one hour "module" inside a required communications skills class at a small private university. Approaches taken included control sessions (a straightforward PowerPoint presentation of the material), direct instruction sessions (featuring mostly direct lecture but with some seatwork as well), and student-centered sessions (utilizing role playing and group exercises). Students were taught basic content and definitions regarding plagiarism, what circumstances or instances constitute plagiarism, where to go for help in avoiding plagiarism, and what constitutes appropriate paraphrasing and citation. Pre-test and post-test scores determined students' functional understanding primarily by their ability to recognize properly and improperly paraphrased text, content understanding by their combined total score on a multiple choice quiz, and their attitude and conceptual understanding by their ability to recognize circumstances which would constitute plagiarism. While students improved across all methods the study was unable to identify one that performed significantly better than the others. The results supported the need for more education with regard to plagiarism and suggested a need for perhaps more time on task and/or a mixed approach towards conveying the content.
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In China in particular, large, planned special events (e.g., the Olympic Games, etc.) are viewed as great opportunities for economic development. Large numbers of visitors from other countries and provinces may be expected to attend such events, bringing in significant tourism dollars. However, as a direct result of such events, the transportation system is likely to face great challenges as travel demand increases beyond its original design capacity. Special events in central business districts (CBD) in particular will further exacerbate traffic congestion on surrounding freeway segments near event locations. To manage the transportation system, it is necessary to plan and prepare for such special events, which requires prediction of traffic conditions during the events. This dissertation presents a set of novel prototype models to forecast traffic volumes along freeway segments during special events. Almost all research to date has focused solely on traffic management techniques under special event conditions. These studies, at most, provided a qualitative analysis and there was a lack of an easy-to-implement method for quantitative analyses. This dissertation presents a systematic approach, based separately on univariate time series model with intervention analysis and multivariate time series model with intervention analysis for forecasting traffic volumes on freeway segments near an event location. A case study was carried out, which involved analyzing and modelling the historical time series data collected from loop-detector traffic monitoring stations on the Second and Third Ring Roads near Beijing Workers Stadium. The proposed time series models, with expected intervention, are found to provide reasonably accurate forecasts of traffic pattern changes efficiently. They may be used to support transportation planning and management for special events.
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The problems to be solved in this thesis were 1) development of a broadband RF preamplifier to be used with non-ferrous current probes so that the amplified signal exceeds the errors due to cable pickup, no detection is needed in this application, and 2) development of a self-contained device that amplifies and detects the output from a nonferrous current probe, providing a digital readout of the current. These instruments have been completed and are being tested for use by the National Institutes of Occupational Safety and Health (NIOSH). The self-contained current meter operates at frequencies up to 600 MHz, and detects currents as low as 8 mA . At these current magnitudes, the probe (pick-up coil) will output a voltage of 500μV (-53 dBm on 50Ω) which will have to be raised above 0 dBm. The final circuit uses a RF mixer as a variable attenuator in order to increase the dynamic range, two Monolithic Microwave Integrated Circuits (MMIC) for preamplification, a final broadband amplifier to raise the output compression point, a Schottky diode detector, a sample and hold circuit, and a liquid crystal digital panel meter.
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This thesis was elaborated in the scenario of Digital Metropolis Institute (IMD) – a supplementary unit at the Federal University of Rio Grande do Norte in the training of personnel with technical and higher level courses whose technical level training is associated with a process of digital inclusion, with the purpose of attracting young people to this area, with emphasis on Software and Hardware Development. It aims to investigate the cognitive change of young apprentice on technological education and his/her entrance into the labor market, through the formation and the social inclusion proposed by the Instituto Metrópole Digital; understanding the juvenile subjectivity production through the Instituto Metrópole Digital’s education by performance in the labor market; recognizing the Brazilian professional qualification public policies for youth and identifying the role of Tutoring in the learning process during the course of formation of the young apprentice of the technological education proposed by the Instituto Metrópole Digital.The clipping of the object of investigation was the process of cognitive change and constitution of subjectivity of the young apprentice in information technology (IT) in the IMD. It was searched support in theory Freireana as proposal that problematizes the policies and the process of formation and professional qualification, in the perspective of a citizen and liberating consciousness. By qualitative and ethnographic nature, descriptive-explanatory, it counts with the participation of young people, high school students from public and private schools, aged between 15 and 18 years. There are strong aspects: a cognitive change on the young apprentice of technological education onto overdrive high school as the student of the Instituto Metrópole Digital; it happened the social integration for those who remain in the course, both in the neighborhood where they reside and at school where he attended high school, the young man is recognized and becomes reference to other young, favoring him a life projection which when the activities of mentoring is learning motivator, it exerts a positive influence to the young on the continuity of studies, it provides intellectual and institutional affiliation and continuity in the investments to the academic life for a better insertion in the labor market, which refers to the modification of the life project-invest in academic training, in exchange for a technical job in the labor market. There are weak aspects: the absence of professor in the course, in his most important role, which involves awareness of his/her condition in action, in explicit position that the professional practice constitutes as this constitution requires reciprocity of its students and the context in which it operates; fragile formation of mentoring, absence of dialogues in the classroom that favors the formation of subject learning, mainly in guiding action, mediator of the young; There is a lack of methodological proposal to develop real projects on the labor market with problem solving and collaborative learning. It considers that without converting information into knowledge cannot discern clearly enough that there is no direct causal relationship between Professional and technological Education and the level of employability of the young worker certificate. It suggests to the evasion: a greater knowledge of the reality of the student of the Institute Metropolis Digital; better knowledge of youth and their expectations of life project; the Tutoring will be Teacher-tutor; investing in employability conditions effective the young into the labor market.
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Stroke is nowadays one of the main causes of death in Brazil and worldwide. During the rehabilitation process, patients undergo physioterapic exercises based on repetition, which may cause them to feel little progress is being made. Focusing on themes from the areas of Human-Computer Interaction and Motor Imagery, the present work describes the development of a digital game concept aimed at motor rehabilitation to the neural rehabilitation of patients who have suffered a stroke in a playful and engaging way. The research hypothesizes that an interactive digital game based on Motor Imagery contributes to patients' raised commitment in the stroke sequel rehabilitation process. The research process entailed the investigation of 10 subjects who live with sequels caused by stroke - it was further established that subjects were over 60 years old. Using as foundation an initial survey regarding target-users' specificities, where an investigation on subjectrelated aspects was carried out through Focus Group (n=9) and Contextual Analysis (n=3), having as subjects elderly individuals, a list with the necessary requirements for the conceptualization of a digital game was fleshed out. The initial survey also enabled the establishment of preliminary interactions for the formulation of game prototypes. At first, low-resolution prototypes were used, with two distinct interaction models for the game - one with a direct approach to the Motor Imagery concept, and another using a narrative with characters and scene settings. The goal was to verify participants' receptivity regarding the addition of playful activities into game dynamics. Prototypes were analyzed while being used by five patients, through the Cooperative Evaluation technique. The tests indicated a preference for option with elements in a playful narrative. Based on these results high fidelity prototypes were created, where concepts close to the game's final version were elaborated. The High Fidelity prototype was also evaluated with four patients through the Cooperative Evaluation technique. It was concluded that elderly individuals and patients were receptive to the idea of a digital game for the rehabilitation from sequels caused by stroke; that, for the success of devices aimed at these cohorts, their contexts, needs and expectations must be respected above all; and that user-centered design is an essential approach in that regard.
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Aims To investigate the predictive ability of four digital assessment parameters to detect levator ani (LA) muscle defects (avulsion injury) and compare these to transperineal tomographic ultrasound images. Methods This was an observational study imbedded in a larger quasi-experimental cohort study for women with urinary incontinence. Seventy-two women, ≥60 years who had attended or were going to attend physiotherapy for treatment of urinary incontinence, were included in the study. Inclusion criteria from the parent study were symptoms of stress, urge or both types of urinary incontinence. The predictive ability of the following digital parameters: direct palpation of a discontinuity of the LA muscle from insertion on the pubic ramus; palpation of the distance between the muscle insertion sites; palpation of LA strength; palpation of LA tone, were analyzed against findings from tomographic transperineal ultrasound images. Correlation between methods was measured using Cohen's kappa for each of the individual parameters. Results Seventeen women (24%) presented with a complete or partial avulsion of the puborectalis muscle as diagnosed with tomographic ultrasound imaging. Nine women (13%) had complete avulsions, one of which was bilateral. The predictive ability of the digital assessment parameters varied from poor (k = 0.187, 95% CI [0.02–0.36]) to moderate (k = 0.569, 95% CI [0.31–0.83]). The new parameter of ‘width between insertion sites’ performed best. Conclusions Adding the parameter of “width between insertion sites” appears to enhance our ability to detect avulsion of the levator ani (LA) muscle by digital examination however it does not distinguish between unilateral or bilateral avulsion.
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Aims To investigate the predictive ability of four digital assessment parameters to detect levator ani (LA) muscle defects (avulsion injury) and compare these to transperineal tomographic ultrasound images. Methods This was an observational study imbedded in a larger quasi-experimental cohort study for women with urinary incontinence. Seventy-two women, ≥60 years who had attended or were going to attend physiotherapy for treatment of urinary incontinence, were included in the study. Inclusion criteria from the parent study were symptoms of stress, urge or both types of urinary incontinence. The predictive ability of the following digital parameters: direct palpation of a discontinuity of the LA muscle from insertion on the pubic ramus; palpation of the distance between the muscle insertion sites; palpation of LA strength; palpation of LA tone, were analyzed against findings from tomographic transperineal ultrasound images. Correlation between methods was measured using Cohen's kappa for each of the individual parameters. Results Seventeen women (24%) presented with a complete or partial avulsion of the puborectalis muscle as diagnosed with tomographic ultrasound imaging. Nine women (13%) had complete avulsions, one of which was bilateral. The predictive ability of the digital assessment parameters varied from poor (k = 0.187, 95% CI [0.02–0.36]) to moderate (k = 0.569, 95% CI [0.31–0.83]). The new parameter of ‘width between insertion sites’ performed best. Conclusions Adding the parameter of “width between insertion sites” appears to enhance our ability to detect avulsion of the levator ani (LA) muscle by digital examination however it does not distinguish between unilateral or bilateral avulsion.
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Thesis (Master's)--University of Washington, 2016-08
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Phase change problems arise in many practical applications such as air-conditioning and refrigeration, thermal energy storage systems and thermal management of electronic devices. The physical phenomenon in such applications are complex and are often difficult to be studied in detail with the help of only experimental techniques. The efforts to improve computational techniques for analyzing two-phase flow problems with phase change are therefore gaining momentum. The development of numerical methods for multiphase flow has been motivated generally by the need to account more accurately for (a) large topological changes such as phase breakup and merging, (b) sharp representation of the interface and its discontinuous properties and (c) accurate and mass conserving motion of the interface. In addition to these considerations, numerical simulation of multiphase flow with phase change introduces additional challenges related to discontinuities in the velocity and the temperature fields. Moreover, the velocity field is no longer divergence free. For phase change problems, the focus of developmental efforts has thus been on numerically attaining a proper conservation of energy across the interface in addition to the accurate treatment of fluxes of mass and momentum conservation as well as the associated interface advection. Among the initial efforts related to the simulation of bubble growth in film boiling applications the work in \cite{Welch1995} was based on the interface tracking method using a moving unstructured mesh. That study considered moderate interfacial deformations. A similar problem was subsequently studied using moving, boundary fitted grids \cite{Son1997}, again for regimes of relatively small topological changes. A hybrid interface tracking method with a moving interface grid overlapping a static Eulerian grid was developed \cite{Juric1998} for the computation of a range of phase change problems including, three-dimensional film boiling \cite{esmaeeli2004computations}, multimode two-dimensional pool boiling \cite{Esmaeeli2004} and film boiling on horizontal cylinders \cite{Esmaeeli2004a}. The handling of interface merging and pinch off however remains a challenge with methods that explicitly track the interface. As large topological changes are crucial for phase change problems, attention has turned in recent years to front capturing methods utilizing implicit interfaces that are more effective in treating complex interface deformations. The VOF (Volume of Fluid) method was adopted in \cite{Welch2000} to simulate the one-dimensional Stefan problem and the two-dimensional film boiling problem. The approach employed a specific model for mass transfer across the interface involving a mass source term within cells containing the interface. This VOF based approach was further coupled with the level set method in \cite{Son1998}, employing a smeared-out Heaviside function to avoid the numerical instability related to the source term. The coupled level set, volume of fluid method and the diffused interface approach was used for film boiling with water and R134a at the near critical pressure condition \cite{Tomar2005}. The effect of superheat and saturation pressure on the frequency of bubble formation were analyzed with this approach. The work in \cite{Gibou2007} used the ghost fluid and the level set methods for phase change simulations. A similar approach was adopted in \cite{Son2008} to study various boiling problems including three-dimensional film boiling on a horizontal cylinder, nucleate boiling in microcavity \cite{lee2010numerical} and flow boiling in a finned microchannel \cite{lee2012direct}. The work in \cite{tanguy2007level} also used the ghost fluid method and proposed an improved algorithm based on enforcing continuity and divergence-free condition for the extended velocity field. The work in \cite{sato2013sharp} employed a multiphase model based on volume fraction with interface sharpening scheme and derived a phase change model based on local interface area and mass flux. Among the front capturing methods, sharp interface methods have been found to be particularly effective both for implementing sharp jumps and for resolving the interfacial velocity field. However, sharp velocity jumps render the solution susceptible to erroneous oscillations in pressure and also lead to spurious interface velocities. To implement phase change, the work in \cite{Hardt2008} employed point mass source terms derived from a physical basis for the evaporating mass flux. To avoid numerical instability, the authors smeared the mass source by solving a pseudo time-step diffusion equation. This measure however led to mass conservation issues due to non-symmetric integration over the distributed mass source region. The problem of spurious pressure oscillations related to point mass sources was also investigated by \cite{Schlottke2008}. Although their method is based on the VOF, the large pressure peaks associated with sharp mass source was observed to be similar to that for the interface tracking method. Such spurious fluctuation in pressure are essentially undesirable because the effect is globally transmitted in incompressible flow. Hence, the pressure field formation due to phase change need to be implemented with greater accuracy than is reported in current literature. The accuracy of interface advection in the presence of interfacial mass flux (mass flux conservation) has been discussed in \cite{tanguy2007level,tanguy2014benchmarks}. The authors found that the method of extending one phase velocity to entire domain suggested by Nguyen et al. in \cite{nguyen2001boundary} suffers from a lack of mass flux conservation when the density difference is high. To improve the solution, the authors impose a divergence-free condition for the extended velocity field by solving a constant coefficient Poisson equation. The approach has shown good results with enclosed bubble or droplet but is not general for more complex flow and requires additional solution of the linear system of equations. In current thesis, an improved approach that addresses both the numerical oscillation of pressure and the spurious interface velocity field is presented by featuring (i) continuous velocity and density fields within a thin interfacial region and (ii) temporal velocity correction steps to avoid unphysical pressure source term. Also I propose a general (iii) mass flux projection correction for improved mass flux conservation. The pressure and the temperature gradient jump condition are treated sharply. A series of one-dimensional and two-dimensional problems are solved to verify the performance of the new algorithm. Two-dimensional and cylindrical film boiling problems are also demonstrated and show good qualitative agreement with the experimental observations and heat transfer correlations. Finally, a study on Taylor bubble flow with heat transfer and phase change in a small vertical tube in axisymmetric coordinates is carried out using the new multiphase, phase change method.
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Recent developments in the general equilibrium theory of multinationals emphasize the importance of multilateral considerations. Yet, existing explanations and corresponding estimations of FDI patterns have largely limited political and institutional investment impediments to a bilateral framework. Through the application of spatial econometric techniques, I demonstrate that the presence of both domestic and regional political uncertainty generate real options effects that lead to the delay or redirection of foreign direct investment. The magnitude and direction of these effects is conditional upon the host country regime type and the predominant multinational integration strategies in the region. Comparing these results with FDI of U.S. origin, I find evidence for divergent investment behavior by U.S. multinationals during regime changes in partner countries. Additionally, I find no evidence that multinationals from developing countries are more likely to complete cross-border deals in environments characterized by greater political risk or political uncertainty.
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Understanding and measuring the interaction of light with sub-wavelength structures and atomically thin materials is of critical importance for the development of next generation photonic devices. One approach to achieve the desired optical properties in a material is to manipulate its mesoscopic structure or its composition in order to affect the properties of the light-matter interaction. There has been tremendous recent interest in so called two-dimensional materials, consisting of only a single to a few layers of atoms arranged in a planar sheet. These materials have demonstrated great promise as a platform for studying unique phenomena arising from the low-dimensionality of the material and for developing new types of devices based on these effects. A thorough investigation of the optical and electronic properties of these new materials is essential to realizing their potential. In this work we present studies that explore the nonlinear optical properties and carrier dynamics in nanoporous silicon waveguides, two-dimensional graphite (graphene), and atomically thin black phosphorus. We first present an investigation of the nonlinear response of nanoporous silicon optical waveguides using a novel pump-probe method. A two-frequency heterodyne technique is developed in order to measure the pump-induced transient change in phase and intensity in a single measurement. The experimental data reveal a characteristic material response time and temporally resolved intensity and phase behavior matching a physical model dominated by free-carrier effects that are significantly stronger and faster than those observed in traditional silicon-based waveguides. These results shed light on the large optical nonlinearity observed in nanoporous silicon and demonstrate a new measurement technique for heterodyne pump-probe spectroscopy. Next we explore the optical properties of low-doped graphene in the terahertz spectral regime, where both intraband and interband effects play a significant role. Probing the graphene at intermediate photon energies enables the investigation of the nonlinear optical properties in the graphene as its electron system is heated by the intense pump pulse. By simultaneously measuring the reflected and transmitted terahertz light, a precise determination of the pump-induced change in absorption can be made. We observe that as the intensity of the terahertz radiation is increased, the optical properties of the graphene change from interband, semiconductor-like absorption, to a more metallic behavior with increased intraband processes. This transition reveals itself in our measurements as an increase in the terahertz transmission through the graphene at low fluence, followed by a decrease in transmission and the onset of a large, photo-induced reflection as fluence is increased. A hybrid optical-thermodynamic model successfully describes our observations and predicts this transition will persist across mid- and far-infrared frequencies. This study further demonstrates the important role that reflection plays since the absorption saturation intensity (an important figure of merit for graphene-based saturable absorbers) can be underestimated if only the transmitted light is considered. These findings are expected to contribute to the development of new optoelectronic devices designed to operate in the mid- and far-infrared frequency range. Lastly we discuss recent work with black phosphorus, a two-dimensional material that has recently attracted interest due to its high mobility and direct, configurable band gap (300 meV to 2eV), depending on the number of atomic layers comprising the sample. In this work we examine the pump-induced change in optical transmission of mechanically exfoliated black phosphorus flakes using a two-color optical pump-probe measurement. The time-resolved data reveal a fast pump-induced transparency accompanied by a slower absorption that we attribute to Pauli blocking and free-carrier absorption, respectively. Polarization studies show that these effects are also highly anisotropic - underscoring the importance of crystal orientation in the design of optical devices based on this material. We conclude our discussion of black phosphorus with a study that employs this material as the active element in a photoconductive detector capable of gigahertz class detection at room temperature for mid-infrared frequencies.
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Present the measurement of a rare Standard Model processes, pp →W±γγ for the leptonic decays of the W±. The measurement is made with 19.4 fb−1 of 8 TeV data collected in 2012 by the CMS experiment. The measured cross section is consistent with the Standard Model prediction and has a significance of 2.9σ. Limits are placed on dimension-8 Effective Field Theories of anomalous Quartic Gauge Couplings. The analysis has particularly sensitivity to the fT,0 coupling and a 95% confidence limit is placed at −35.9 < fT,0/Λ4< 36.7 TeV−4. Studies of the pp →Zγγ process are also presented. The Zγγ signal is in strict agreement with the Standard Model and has a significance of 5.9σ.
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Photosynthesis –the conversion of sunlight to chemical energy –is fundamental for supporting life on our planet. Despite its importance, the physical principles that underpin the primary steps of photosynthesis, from photon absorption to electronic charge separation, remain to be understood in full. Electronic coherence within tightly-packed light-harvesting (LH) units or within individual reaction centers (RCs) has been recognized as an important ingredient for a complete understanding of the excitation energy transfer (EET) dynamics. However, the electronic coherence across units –RC and LH or LH and LH –has been consistently neglected as it does not play a significant role during these relatively slow transfer processes. Here, we turn our attention to the absorption process, which, as we will show, has a much shorter built-in timescale. We demonstrate that the- often overlooked- spatially extended but short-lived excitonic delocalization plays a relevant role in general photosynthetic systems. Most strikingly, we find that absorption intensity is, quite generally, redistributed from LH units to the RC, increasing the number of excitations which can effect charge separation without further transfer steps. A biomemetic nano-system is proposed which is predicted to funnel excitation to the RC-analogue, and hence is the first step towards exploiting these new design principles for efficient artificial light-harvesting.