937 resultados para POWER SPECTRUM ANALYSIS


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This paper presents an analytical model of fuel consumption (AMFC) to coordinate the driving power and manage the overall fuel consumption for an internal combustion engine vehicle. The model calculates the different loads applied on the vehicle including road-slope, road-friction, wind-drag, accessories, and mechanical losses. Also, it solves the combustion equation of the engine under different working conditions including various fuel compositions, excess airs and air inlet temperatures. Then it determines the contribution of each load to signify the energy distribution and power flows of the vehicle. Unlike the conventional models in which the vehicle speed needs to be given as an input, the developed model can predict the vehicle speed and acceleration under different working conditions by allowing the speed to vary within a predefined range only. Furthermore, the model indicates the ways to minimises the vehicles' fuel consumption under various driving conditions. The results show that the model has the potential to assist in the vehicle energy management.

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This OXADM are located in the nodes, which have more than two switching directions in ring networks. The function of OXADM is to flexibility switch the wavelengths among the different input and output ports. Because of the OXADM's imperfect performance, the insertion loss and crosstalk are induced in the system. Analytical modeling method is using to analyze the OXADM structure in crosstalk or power leakage that lead to the power penalty. To overcome this problem, power penalty is needed to be supplied. The insertion of this power penalty depends on few parameters. The parameters that we going to investigate here will be in term of number of operating wavelengths and number of input/output ports as well as the Q factor. The variation of this parameters will affects the amount of the desired power penalty. Simulation results in higher crosstalk or higher power penalty needed as the number of OXADM increases. As the sum of the wavelength and the number of input/output for each OXADM increases, the power penalty will increased as well. Investigation on the maximum Q factors is 6 to get the minimum power penalty at the lowest BER for most of the combination of the sum of the wavelength and the number of input/output for each OXADM.

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One of the most intriguing elements of the study of celebrity is the complex relationship between the renowned individuals that have celebrity status and the populace. In past work, I have identified how celebrities “embody” audiences producing a kind of audience-subjectivity that is both collective and individual. If our media systems are producing slightly different collective configurations and quite different ways in which individuals exhibit and share, this relationship between the individual and the collective so foregrounded by celebrity culture may be differently constituted. This presentation will look at how the celebration of the self is played out now across culture in variations of the social and para-social structures of celebrity culture, in professional settings and what would be seen as forms of online leisure and recreational activities. In one sense, this is the spectre of celebrity that has now been virtualised by individuals and their forms of public display. In another sense, we now have a very diverse range and spectrum of public personalities which demands a more extensive analysis of the constitution of public persona, where the embodiment of collectives and the articulation of identity forms for different purposes and objectives produce via a series of micro-publics a substantially different public sphere.

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It has been consistently reported that children with autism spectrum disorders (ASD) show considerable handwriting difficulties, specifically relating to accurate and consistent letter formation, and maintaining appropriate letter size. The aim of this study was to investigate the underlying factors that contribute to these difficulties, specifically relating to motor control.

We examined the integrity of fundamental handwriting movements and contributions of neuromotor noise in 26 children with ASD aged 8-13 years (IQ. >. 75), and 17 typically developing controls. Children wrote a series of four cursive letter l's using a graphics tablet and stylus.

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with ASD had significantly larger stroke height and width, more variable movement trajectory, and higher movement velocities. The absolute level of neuromotor noise in the velocity profiles, as measured by power spectral density analysis, was significantly higher in children with ASD; relatively higher neuromotor noise was found in bands >3. Hz.

Our findings suggest that significant instability of fundamental handwriting movements, in combination with atypical biomechanical strategies, contribute to larger and less consistent handwriting in children with ASD.

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This paper presents an analysis of optimum rectifier circuits for wireless energy harvesting in deep brain stimulation (DBS) devices. Since DBS demands compact and low power consumption devices, small, high conversion efficient, and high output voltage rectifiers need to be developed. The investigation that is presented in this paper is analytical and simulated based. Analysis on a variety of circuit configurations brings more evidence to improve the performance of rectifiers. Analytical parameters influencing the output DC voltage and the efficiency of the rectifiers are described. The operating frequency of the 915 MHz industrial, scientific and medical (ISM) radio band is used in this study. The maximum conversion efficiency of the LC matched half wave rectifier, the Greinacher voltage doubler, the Delon doubler, and the 2-stage voltage multiplier is obtained as 56.34%, 74.45%, 71.48%, and 31.44%, respectively, at the 30 dBm input power level. The corresponding maximum output DC voltages are 6.27 V, 16.83 V, 13.36 V, and 9.20 V. Thus the Greinacher voltage doubler is deemed as the best configuration according to the conversion efficiency and the output voltage measurements.

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Current growth of individuals on the autism spectrum disorder (ASD) requires continuous support and care. With the popularity of social media, online communities of people affected by ASD emerge. This paper presents an analysis of these online communities through understanding aspects that differentiate such communities. In this paper, the aspects given are not expressed in terms of friendship, exchange of information, social support or recreation, but rather with regard to the topics and linguistic styles that people express in their on-line writing. Using data collected unobtrusively from LiveJournal, we analyze posts made by ten autism communities in conjunction with those made by a control group of standard communities. Significant differences have been found between autism and control communities when characterized by latent topics of discussion and psycholinguistic features. Latent topics are found to have greater predictive power than linguistic features when classifying blog posts as either autism or control community. This study suggests that data mining of online blogs has the potential to detect clinically meaningful data. It opens the door to possibilities including sentinel risk surveillance and harnessing the power in diverse large datasets.

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Public health advocates have repeatedly highlighted parallels between food marketing and childhood obesity. Yet existing literature has not explored the connection between the promotion of unhealthy foods and beverages, certain characteristics of integrated marketing communication (IMC) and the power of multinational food and beverage companies. This is problematic because IMC represents the dominant marketing paradigm in use today. This article draws on critical theory and literature from across public health, marketing, business and related fields. By focusing on macro-level antecedents and interactions, this discussion highlights a previously unarticulated dimension of the promotion of unhealthy foods and beverages to children and adolescents. In doing so, this discussion aims to generate greater recognition of the broader environmental circumstances and processes that surround food marketing tactics and their consequences for public health nutrition. This perspective will also contribute to an expanded understanding of unhealthy food marketing and its unintended consequences, among an audience of nutrition, public health and policy communities.

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This paper discusses pre-service teachers' responses to a critical analysis of gender/power relations using examples from a final assessment for an intensive elective unit called Teaching Sexuality in the Middle Years. This unit critically examines gender/ power relations, the production of difference, heteronormativity and pleasure and desire, employing a feminist post-structural framework. Despite the focus on critical thinking, reflection and interrogating structural inequalities in this unit some students were resistant or unable to engage with this approach in their assessments, although appearing to do so in workshops. We consider the broad range of sexuality education discourses mobilised by this unit to try to make sense of what looks like resistance but may be something more complex and difficult to negotiate. The paper ends with a consideration of some of the implications of this approach for practice.

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Power system stabilizers (PSSs) are extensively used to ensure the dynamic stability of power systems through the modulation of excitation signals supplied to synchronous generators. This paper presents a comparative study of two different PSSs: STAB1 and IEEEST. The stabilizers are designed for the linearized model of a single machine infinite bus (SMIB) system with different loads. Both time-and frequency-domain simulations are carried out to investigate the performance of these stabilizers. For all PSSs, the time-domain simulations are performed by applying a three-phase short-circuit fault at the terminal of the synchronous generator. These simulation results are compared against the open-loop characteristics of the SMIB system where no PSS is implemented. Simulation results demonstrate that the speed-fed PSS provides more damping as compared to frequency- and power-fed stabilizers.