3,870 research outputs found

    Frequency-dependent photothermal measurement of thermal diffusivity for opaque and non-opaque materials; Application to crystals of TIPS-pentacene

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    We propose the use of a frequency-dependent photothermal measurement as a complement to light-flash, i.e. time-dependent, measurements to determine the through-plane thermal diffusivity of small, thin samples, e.g. semiconducting polymers and small organic molecule crystals. The analysis is extended from its previous use with some opaque conducting polymers to materials with finite absorption coefficients, such as crystals of 6,13-bis(triisopropylsilylethynyl pentacene ("TIPS-pentacene"). Taking into account the finite absorption coefficients of the latter gives a value of diffusivity, D=0.10 mm2/s, much smaller than previously estimated and more consistent with its expected value. We also briefly discuss the effects of coating samples for the measurement to improve their optical properties.Comment: 11 pages, 6 figures, to be published in Journal of Applied Physic

    An overview of very high level software design methods

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    Very High Level design methods emphasize automatic transfer of requirements to formal design specifications, and/or may concentrate on automatic transformation of formal design specifications that include some semantic information of the system into machine executable form. Very high level design methods range from general domain independent methods to approaches implementable for specific applications or domains. Applying AI techniques, abstract programming methods, domain heuristics, software engineering tools, library-based programming and other methods different approaches for higher level software design are being developed. Though one finds that a given approach does not always fall exactly in any specific class, this paper provides a classification for very high level design methods including examples for each class. These methods are analyzed and compared based on their basic approaches, strengths and feasibility for future expansion toward automatic development of software systems

    Strategi Marketing Public Relations dalam Meningkatkan Jumlah Tamu Hotel Pantai Marina Bengkalis

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    Companies use promotions to convey expected messages to audiences and may influence public perceptions and actions. The function of Public Relations in achieving the company\u27s goal is to increase the hotel guest\u27s visit, a PR must have a Marketing Public Relations strategy as a priority plan to achieve the company\u27s goals, one of which attracts customers to continue to use their services. Seeing the business competition in the field of hospitality makes the businessmen have to think hard to create the best Marketing Public Relations strategy in order to attract customers. It takes a marketing strategy to increase the guest\u27s visit at the Marina Beach Hotel. From the data the researchers get in the field on pre-observation, the researcher is interested to conduct this research with the aim to see the marketing strategy of Public Relations used in improving the guest\u27s visit at this hotel.This research is a descriptive research using qualitative approach as a tool of its analysis. This researcher informant is from Hotel Pantai Marina is Manager, Assistant Manager, Secretary HRD Hotel Marina Beach as well as hotel visitors as many as 8 people. Observation data collection techniques, interviews and documentation. Technique of data analysis writer use in this research is descriptive qualitative. The result of the research is Public Relations Marketing Strategy through Information in improving guest visit of Marina Bengkalis Beach Hotel done by giving information through media in the form of facebook, spreading a brochure or pamphlet installation, Marketing Public Relations strategy through public service in increasing guest visit Hotel Marina Bengkalis Beach done By providing good service and being hospitable, Marketing Public Relations Strategy through publication in improving the visit of Marina Bengkalis Beach Hotel is done by intensifying promotion in print media and social media, deploying special promos related products and services offered by the Hotel

    Networked Drones for Industrial Emergency Events

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    Uncontrolled emissions of gases from industrial accidents and disasters result in huge loss of life and property. Such extreme events require a quick and reliable survey of the site for effective rescue strategy planning. To achieve these goals, a network of unmanned aerial vehicles can be deployed that survey the affected region and identify safe and danger zones. Although single UAV-based systems for gas sensing applications are well-studied in literature, research on the deployment of a UAV network for such applications, which is more robust and fault tolerant, is still in infancy. The objective of this project is to design a system that can be deployed in emergency situations to provide a quick survey and identification of safe and dangerous zones in a given region that contains a toxic plume without making any assumptions about plume location. We focus on an end-to-end solution and formulate a two-phase strategy that can not only guarantee detection/acquisition of plume but also its characterization with high spatial resolution. To guarantee coverage of the region with a certain spatial resolution, we set up a vehicle routing problem. To overcome the limitations imposed by limited range of sensors and drone resources, we estimate the concentration map by using Gaussian kernel extrapolation. Finally, we evaluate the suggested framework in simulations. Our results suggest that this two-phase strategy not only gives better error performance but is also more efficient in terms of mission time. Moreover, the comparison between 2-phase random search and 2-phase uniform coverage suggest that the latter is better for single drone systems whereas for multiple drones the former gives reasonable performance at low computational cost

    Frequency-Dependent Photothermal Measurement of Thermal Diffusivity for Opaque and Non-Opaque Materials: Application to Crystals of TIPS-Pentacene

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    We propose the use of a frequency-dependent photothermal measurement as a complement to light-flash, i.e., time-dependent, measurements to determine the through-plane thermal diffusivity of small, thin samples, e.g., semiconducting polymers and small organic molecule crystals. The analysis is extended from its previous use with some opaque conducting polymers to materials with finite absorption coefficients, such as crystals of 6,13-bis(triisopropylsilylethynyl)pentacene. Taking into account the finite absorption coefficients of the latter gives a value of diffusivity, D ≈ 0.10 mm2/s, much smaller than previously estimated and more consistent with its expected value. We also briefly discuss the effects of coating samples for the measurement to improve their optical properties

    Strategy for reliable strain measurement in InAs/GaAs materials from high-resolution Z-contrast STEM images

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    Geometric phase analysis (GPA), a fast and simple Fourier space method for strain analysis, can give useful information on accumulated strain and defect propagation in multiple layers of semiconductors, including quantum dot materials. In this work, GPA has been applied to high resolution Z-contrast scanning transmission electron microscopy (STEM) images. Strain maps determined from different g vectors of these images are compared to each other, in order to analyze and assess the GPA technique in terms of accuracy. The SmartAlign tool has been used to improve the STEM image quality getting more reliable results. Strain maps from template matching as a real space approach are compared with strain maps from GPA, and it is discussed that a real space analysis is a better approach than GPA for aberration corrected STEM images

    Parafoveal processing of orthographic, morphological, and semantic information during reading Arabic: A boundary paradigm investigation

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    Evidence shows that skilled readers extract information about upcoming words in the parafovea. Using the boundary paradigm, we investigated native Arabic readers\u27 processing of orthographic, morphological, and semantic information available parafoveally. Target words were embedded in frame sentences, and prior to readers fixating them, one of the following previews were made available: (a) Identity preview; (b) Preview that shared the pattern morpheme with the target; (c) Preview that shared the root morpheme with the target; (d) Preview that was a synonym with the target word; (e) Preview with two of the root letters were transposed thus creating a new root, while preserving all letter identities of the target; (f) Preview with two of the root letters were transposed thus creating a pronounceable pseudo root, while also preserving all letter identities of the target; and (g) Previews that was unrelated to the target word and shared no information with it. The results showed that identity, root-preserving, and synonymous preview conditions yielded preview benefit. On the other hand, no benefit was obtained from the pattern-preserving previews, and significant disruption to processing was obtained from the previews that contained transposed root letters, particularly when this letter transposition created a new real root. The results thus reflect Arabic readers\u27 dependance on morphological and semantic information, and suggest that these levels of representation are accessed as early as orthographic information. Implications for theory- and model-building, and the need to accommodate early morphological and semantic processing activities in more comprehensive models are further discussed. Copyright
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