580 research outputs found
FPGA based maximum power point tracking controller for photovoltaic system
Nowadays, PV cell which is known as a photovoltaic is one of the most
important parts in electrical field to convert photolight to voltage and current at the
desired output voltage and frequency by using varies control techniques. This project
presents design and implementation of FPGA Based Maximum Power Point
Tracking (MPPT) Controller for Photovoltaic system. The MPPT controller is
employed to control and get Maximum Power Point (MPP) of the output voltage
reference from the source. Altera DE2 board devices are used as a controller for the
implementation of the MPPT system. The simulation of this FPGA based MPPT
controller is designed and implemented using Quartus II VHDL software tools. The
results shown, the same signal obtained from Matlab simulink software as compared
with Quartus II. It has been observed that the designed system has been successfully
extracting the MPP from the pseudo sources used in the simulations. The system has
been evaluated in sunny day and partially shaded conditions to analyze the
respective outputs in these conditions
Selection and experimental evaluation of low-cost porous materials for regenerator applications in thermoacoustic engines
This paper aims at evaluating three selected low-cost porous materials from the point of view of their suitability as regenerator materials in the design of thermoacoustic travelling wave engines. The materials tested include: a cellular ceramic substrate with regular square channels; steel âscourersâ; and stainless steel âwoolâ. Comparisons are made against a widely used regenerator material: stainless
steel woven wire mesh screen. For meaningful comparisons, the materials are selected to have similar hydraulic radii. One set of regenerators was designed around the hydraulic radius of 200 ÎŒm. This included the ceramic substrate, steel âscourersâ, stainless steel âwoolâ and stacked wire screens (as a reference). This set was complemented by steel âscourersâ and stacked wire screens (as a reference) with
hydraulic radii of 120 ÎŒm. Therefore six regenerators were produced to carry out the testing. Initial tests were made in a steady air flow to estimate their relative pressure drop due to viscous dissipation. Subsequently, they were installed in a looped-tube travelling-wave thermoacoustic engine to test their relative performance. Testing included the onset temperature difference, the maximum pressure amplitude
generated and the acoustic power output as a function of mean pressure between 0 and 10 bar above atmospheric. It appears that the performance of regenerators made out of âscourersâ and steel âwoolâ is much worse than their mesh-screen counterparts of the same hydraulic radius. However cellular ceramics may offer an alternative to traditional regenerator materials to reduce the overall system costs. Detailed
discussions are provided
Human values in intercultural communication : CDA for Discourse of Proverbs in Yemen Times / Abduljalil Hazaea
In intercultural communication, human values need to be investigated as neutral discourse; where local and global identities compete to legitimate such neutral discourse. Human values can be explicitly or implicitly manifested in the discourse of proverbs. Proverbs are âcommon senseâ assumptions that construct culturally-biased and durative values. Like newspaper headlines, proverbs are part of argumentative rhetoric whose semantic and pragmatic functions are not only to attract readers but also to convince them. As a subjournalistic genre in Yemen Times, the discourse of proverbs targeted worldwide audiences; it was produced by a non-local journalist and published in hardcopy and online between 2003 and 2010. This paper
investigates human values in an intercultural text disseminated in global journalism; the discourse of proverbs of Yemen Times. The analytical tools of Critical Discourse Analysis (CDA) were employed to reveal the evident competing discourses associated with human values in the texts. The data analysis revealed that human values were associated with literary, philosophical, political and anonymous global discourses; these discourses were dominant in the texts. Local legitimating discourses were excluded; backgrounded local religious discourse and discourse of local passive agency were associated with
human values. The exclusion of local agencies reflects hegemonic global power over human values in intercultural communication
Deep Learning of Scene-Specific Classifier for Pedestrian Detection in Dubai
The performance of a generic pedestrian detector varies based on the data fed to it; when applied to a specific scene, its performance degrades dramatically, which require the detector to be fed with the specific target in mind so that it can produce the desired predictions and detect for the user the specified target. In this paper, I propose to feed the automated specialization of a scene-specific pedestrian detector, with multiple sources from pictures to even videos beginning with a generic video surveillance detector, however manually marking samples to ease the process, as the knowledge accumulated from the master program is still insufficient to produce high-end automated sample marking for the detector. The key idea is to consider a deep detector as a feature that produces a perception of the likelihood of a pedestrian being detected in the target. The system then will be fed with the manually marked samples to enhance its performance and the usage of an already existing system using the Monte Carlo sequential filter system. There has been the implementation of the pedestrian detectors in China, where it showcased the different patterns, the detector can classify and assess whether a pedestrian is present within the testing data or not. The project is truly fascinating as it shows how a machine can learn when fed with the right data and produce sensible results that lead to human renovation and up their living standards by decreasing the number of accidents related to pedestrians affecting the overall rate of accidents. âMany real-world data analysis tasks involve estimating unknown quantities from some given observationsâ as addressed by the authors within their report on Monte Carlo methods (Doucet A., de Freitas N., Gordon N.). In order to compute rational approximations, it is also important to follow numerical techniques. The techniques of Monte Carlo method (MCM) are powerful tools that allow us to achieve this objective (Andrieu C., Doucet A., Punskaya E.)
Toward A Generic Vehicular Cloud Network Architecture: A Case of Virtual Vehicle As A Service
In recent years, cloud computing has gained more and more popularity. The
motivation towards implementing cloud computing in vehicular networks is due to
the availability of communication, storage, and computing resources represented
by communication, vehicles, roadside units (RSUs), and central servers. These
resources can be utilized and provided to vehicles, drivers on the road,
travellers, and customers on the internet. Intelligent Transportation System
(ITS) applications can utilize vehicular cloud computing to provide efficient
real-time services, as well as to improve transportation safety, mobility, and
comfort levels for drivers. In this paper, all possible vehicular cloud models
are presented. Each vehicular cloud model offers different services.
Integrating all vehicular cloud models into one integrated system will provide
all services and serve internet users, passengers, and vehicles. Therefore, a
generic vehicular cloud model is proposed. After that, a new service called
Virtual Vehicle is proposed in vehicular cloud computing. The virtual vehicle
is a virtual machine that migrates from one physical vehicle to another. It
provides the same services as the physical vehicle according to the consumer's
requirements.Comment: 14 page, 7 figure
An Approach to Creative Media Literacy for World Issues
This article introduces an approach to creative media literacy for world issues (WIs) such as Covid-19. In so doing, the article integrates four positions on discourse and media as terrible facets of globalization in the context of critical discourse analysis (CDA). The objectivist position deals with WIs as neutral discourse shared among humanity and distributed through English as an international language and educational media. The ideologist position treats creative media literacy as relations of power between global and local identities in the form of competing discourses associated with WIs. The rhetoric position reveals the hidden strategies used in global media discourse and English as a global language. The social constructionist position provides three levels of analysis for creative media literacy among university students: textual analysis, discourse analysis, and critical discourse analysis. The article concludes with guidelines on how lecturers can implement this approach with EFL students
The impact of a programme for teaching reading comprehension skills on female Saudi students in King Abdulaziz University in Al-Madinah Al-Munawwarah
The present thesis is concerned with the teaching of reading comprehension in Saudi Arabia. Its purpose is to explore ways of improving reading comprehension skills and to investigate the effectiveness of an Experimental Reading Programme devised by the researcher. The experimental reading programme for EFL students was designed based on the basic principles of the use of the communicative approach and the use of authentic materials.This experimental research followed a pre-test, post-test, comparison group design to achieve the above aim. An important limitation to the study, however, was that students in the experimental programme received extra hours of tuition, since the regulations of the centralised system of education required all students to complete the standard curriculum already in place; the experimental programme could only be offered as a supplement. Two instruments, the Reading Achievement Test (multiple choice test) and the Affective Questionnaire (Likert scale) were given to 90 female Saudi students in King Abdulaziz University in Al-Madinah Al-Munawwarah in Saudi Arabia. Students' reading achievement scores before and after the programme were compared, and their attitudes assessed via the Affective Questionnaire.The pre-test of Reading Achievement revealed that the comparison and the experimental groups were similar in score distribution and approximately equal but in the post-test, the mean score of the experimental group was significantly higher than that of the comparison group. This finding shows that students who were taught by the experimental reading programme and trained in reading a variety of authentic reading materials performed better and were able to score higher than the comparison group in the post-test. The t-test result supports this claim; it showed significant differences at (<0.05) p<0.001 level between the two tests. The Affective Questionnaire revealed that students, before the experimental programme, had negative attitudes to the current teaching of reading in English as a foreign language. This impression was confirmed by the fact that they failed to distinguish between teaching methods and teaching materials. This is because the materials drove the teaching methods; in effect, there was no variation in the ways that the teachers taught, because the standard textbook compelled teachers to follow a particular approach. In contrast, the findings obtained from factor analysis showed that students appreciated the experimental programme
The concepts through the mediating effects of psychographic constructs in tourist behavior
The relationships of subjective norms as well as their roles in the causal relationships as constructs are main issues for understanding consumer behavior. Hence, the importance of subjective norms is not covered as a valuable subject. Since there are a few studies about causal relationships of latent variables as mediating effect in the tourism literature; the aim of this article is to pursue and present to discover those precise associations among subjective norms as variables which lead to a new model of them. Expectancy-Value Theory (EVT) and Theory of Planned Behavior (TPB) are employed as the base of created model from Structural Equation Modeling (SEM). Moreover, investigating of subjective issues is very useful to find out consumer behavior, while their concepts are as latent variables or intangibles are very complicated and sophisticated. Besides, tourism literature has a little information through the mediating effects of psychological variables which are led to tourism loyalty. However, the importance of mediating effects is valuable to know the customers how and why to do as well as to predict behavioral intentions. Further, the lack of conceptual framework from mentioned issues is improved by considering variables as subjective and their roles as mediating effects like lifestyle, personality and travel satisfaction between destination image and loyalty
- âŠ