11,491 research outputs found

    Nature of quantum recurrences in coupled higher dimensional systems

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    We investigate recurrence phenomena in coupled two degrees of freedom systems. It is shown that an initial well localized wave packet displays recurrences even in the presence of coupling in these systems. We discuss the interdependence of these time scales namely, classical period and quantum revival time, and explain significance of initial conditions

    Recurrence Tracking Microscope

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    In order to probe nanostructures on a surface we present a microscope based on the quantum recurrence phenomena. A cloud of atoms bounces off an atomic mirror connected to a cantilever and exhibits quantum recurrences. The times at which the recurrences occur depend on the initial height of the bouncing atoms above the atomic mirror, and vary following the structures on the surface under investigation. The microscope has inherent advantages over existing techniques of scanning tunneling microscope and atomic force microscope. Presently available experimental technology makes it possible to develop the device in the laboratory

    The psychometric impacts of Karasek's demands and control scale on employees' job dissatisfaction

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    The aim of this study was to provide the reliability and validity of job factors and to analyze its association with Demands-Control Model and job dissatisfaction in two time cross-sectional study of Distribution Companies of Water and Power Development Authority (WAPDA) in Pakistan. Two times self-reported cross-sectional surveys were conducted, the study samples consisting of 420 respondents at T1 and 388 respondents at T2. Appropriate internal consistencies of the four scales: demands, control, job satisfaction and social supports, were obtained. Zero-order correlation and linear and multiple regressions analysis replicated the theoretically assumed structure of the job factors and job satisfaction construct in men and women collectively. Evidence of criterion validity was obtained from cross-correlations of the scales and from their linear and multiple regression analysis. Finally, all four measures were associated with a highly significant ratio of job dissatisfaction (JD), and the effect was strongest for the JD ratio as predicted by fundamental theory of Karasek. The level of work related to their demands and the level of autonomy and control they enjoy in their work place directly results in satisfaction and wellbeing of employees. Based on the results of this study the four quadrant version of the DCM questionnaire is considered a reliable and valid instrument for measuring psychosocial pressure at work environment. These outcomes and measures are applicable to all services and manufacturing industries

    13th: One Era Calling Out to Another

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    This film review of 13th is featured in the journal Tapestries: Interwoven voices of local and global identities, volume 6

    Word Affect Intensities

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    Words often convey affect -- emotions, feelings, and attitudes. Lexicons of word-affect association have applications in automatic emotion analysis and natural language generation. However, existing lexicons indicate only coarse categories of affect association. Here, for the first time, we create an affect intensity lexicon with real-valued scores of association. We use a technique called best-worst scaling that improves annotation consistency and obtains reliable fine-grained scores. The lexicon includes terms common from both general English and terms specific to social media communications. It has close to 6,000 entries for four basic emotions. We will be adding entries for other affect dimensions shortly

    Development of dual-axis solar tracking using arduino

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    Renewable energy sections are fast-spreading, as they can be considered new growth areas for many countries. Contains many economic and environmental possibilities. As solar energy is considered to have a major and effective role for the acquisition of energy, in the face of the identification of rural areas that are difficult to access electric power. The traditional solar power system used is produces weak energy by assumption that the sun is moving all the day, therefore requires the purchase of more solar panels refer to the high cost .The project aims to develop the traditional solar system to solar tracking system using Arduino, two servo motor and light dependent resistor (LDR) to obtain high efficiency in electric power generation. Where, the main goal agreed is to track the sunlight at its maximum intensity until the panel move towards the sun, and the project is divided into two main parts, the development of software and hardware. In hardware development will be used four LDR installed on plastic base on solar panel, connected wires to transfer the measurements from sensors to Arduino with resistances and Multi-meter to measure the required energy coming from the pane

    Algebraic surface grid generation in three-dimensional space

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    An interactive program for algebraic generation of structured surface grids in three dimensional space was developed on the IRIS4D series workstations. Interactive tools are available to ease construction of edge curves and surfaces in 3-D space. Addition, removal, or redistribution of points at arbitrary locations on a general 3-D surface or curve is possible. Also, redistribution of surface grid points may be accomplished through use of conventional surface splines or a method called 'surface constrained transfinite interpolation'. This method allows the user to redistribute the grid points on the edges of a surface patch; the effect of the redistribution is then propagated to the remainder of the surface through a transfinite interpolation procedure where the grid points will be constrained to lie on the surface. The program was written to be highly functional and easy to use. A host of utilities are available to ease the grid generation process. Generality of the program allows the creation of single and multizonal surface grids according to the user requirements. The program communicates with the user through popup menus, windows, and the mouse
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