10,387 research outputs found

    How to Design and Build Smoother Pavements

    Get PDF
    Smoothness is one of the key functional performances of pavements, used universally for construction acceptance and prioritizing rehabilitation and maintenance. Materials, equipment, and construction operations all play a role in pavement smoothness. Based on decades of experience and engaging case studies, this presentation covers pavement design considerations and construction best practices—recommendations that maximize pavement performance and reduce costs. In addition, it will touch on pavement smoothness specifications, including INDOT’s planned transition to IRI

    Thermal expansion mismatch and plasticity in thermal barrier coating

    Get PDF
    The basic objective of this investigation is the quantitative determination of stress states in a model thermal barrier coating (TBC) as it cools in the air to 600 C from an assumed stress-free state at 700 C. This model is intended to represent a thin plasma-sprayed zirconia-yttria ceramic layer with a nickel chromium-aluminum-yttrium bond coat on a cylindrical substrate made of nickel-based superalloys typically found in gas turbines

    Electrical fixing of 1000 angle-multiplexed holograms in SBN:75

    Get PDF
    We have demonstrated electrical fixing of 1000 angle-multiplexed holograms in a 1-cm^3 volume Ce-doped SBN:75 crystal. A revealing procedure yielded an average diffraction efficiency of 0.005% for each hologram, with approximately 20% variation. The erasure resistance of the fixed gratings was verified

    Interface roughness and planar doping in superlattices: weak localization effects

    Full text link
    We examine the effects of interface roughness and/or planar impurity doping in a superlattice, in the frame of a weak disorder description. We find that these two types of disorder are equivalent, and that they can be viewed as effective "bulk" disorder, with anisotropic diffusion coefficients. Our results offer quantitative insight to transport properties of multilayers and devices, which contain inadvertently structural disorder at the interfaces.Comment: 4 page

    WAQS : a web-based approximate query system

    Get PDF
    The Web is often viewed as a gigantic database holding vast stores of information and provides ubiquitous accessibility to end-users. Since its inception, the Internet has experienced explosive growth both in the number of users and the amount of content available on it. However, searching for information on the Web has become increasingly difficult. Although query languages have long been part of database management systems, the standard query language being the Structural Query Language is not suitable for the Web content retrieval. In this dissertation, a new technique for document retrieval on the Web is presented. This technique is designed to allow a detailed retrieval and hence reduce the amount of matches returned by typical search engines. The main objective of this technique is to allow the query to be based on not just keywords but also the location of the keywords within the logical structure of a document. In addition, the technique also provides approximate search capabilities based on the notion of Distance and Variable Length Don\u27t Cares. The proposed techniques have been implemented in a system, called Web-Based Approximate Query System, which contains an SQL-like query language called Web-Based Approximate Query Language. Web-Based Approximate Query Language has also been integrated with EnviroDaemon, an environmental domain specific search engine. It provides EnviroDaemon with more detailed searching capabilities than just keyword-based search. Implementation details, technical results and future work are presented in this dissertation

    Linear maps on k^I, and homomorphic images of infinite direct product algebras

    Get PDF
    Let k be an infinite field, I an infinite set, V a k-vector-space, and g:k^I\to V a k-linear map. It is shown that if dim_k(V) is not too large (under various hypotheses on card(k) and card(I), if it is finite, respectively countable, respectively < card(k)), then ker(g) must contain elements (u_i)_{i\in I} with all but finitely many components u_i nonzero. These results are used to prove that any homomorphism from a direct product \prod_I A_i of not-necessarily-associative algebras A_i onto an algebra B, where dim_k(B) is not too large (in the same senses) must factor through the projection of \prod_I A_i onto the product of finitely many of the A_i, modulo a map into the subalgebra \{b\in B | bB=Bb=\{0\}\}\subseteq B. Detailed consequences are noted in the case where the A_i are Lie algebras.Comment: 14 pages. Lemma 6 has been strengthened, with resulting strengthening of other results. Some typos etc. have been correcte

    Mems device with large out-of-plane actuation and low-resistance interconnect and methods of use

    Full text link
    Source: United States Patent and Trademark Office, www.uspto.gov”The present application is directed to a MEMS device. The MEMS device includes a substrate having a first end and a second end extending along a longitudinal axis, the Substrate including an electrostatic actuator. The device also includes a movable plate having a first end and a second end. The device also includes a thermal actuator having a first end coupled to the first end of the substrate and a second end coupled to the first end of the plate. The actuator moves the plate in relation to the substrate. Further, the device includes a power source electrically coupled to the thermal actuator and the Substrate. The application is also directed to a method for operating a MEMS device
    • …
    corecore