Doubly functionalized multiwall carbon nanotubes with enhanced solubility

Doubly functionalized multiwall carbon nanotubes (MWCNTs) have been produced by oxidation in concentrated nitric acid and subsequent treatment with lauoroyl peroxide. MWCNTs containing both carboxyl and alkyl functional groups show enhanced solubility in a wide range of polar and nonpolar solvents and epoxy resin.     

Containment passive-cooling design concepts

A containment is proposed for a high rating PWR (1300 MW_e) that makes it possible to reject sufficient heat to maintain internal conditions below design limits during any postulated design basis accident. The proposed containment thus eliminates the need to employ active features for containment cooling, and conformes to guidelines set forth for passive reactor systems. [EPRI, 1987] The design is based in part on a currently operating PWR containment (Waterford 3). A series of modifications and additions are necessary to make passive heat rejection possible. The modifications are an increase in free volume and primary shell surface area. The additions are the perforation of the secondary containment structure to form an air-convection annulus, and allow the submersion of the lower part of the containment into an external pool; an internal pool increases in-containment heat storage. Proposed features are evaluated analytically, computationally and, where possible and necessary, experimentally. The proposed containment is shown to remain below current regulatory limits for the design-basis postulated loss of coolant accident.     

Techno-economical assessment of coal and biomass gasification-based hydrogen production supply chain system

Hydrogen is an energy carrier that represents a possible clean fuel of the future. This paper assesses the effect of biomass co-firing on gasification based hydrogen production supply chain, with carbon dioxide capture and storage, from technical, economical and environmental point of view. Several cases consisting of various feedstocks to the gasification reactor are investigated (coal only and coal in mixture with sawdust or wheat straw). Considered plant concepts generate between 330 and 460 MW hydrogen of 99.99% (vol.) purity.     

Using PC-based data acquisition to prevent turbine blade damagefrom cycling service and for on-line performance monitoring on an81-megawatt steam-cycle electric power generating unit

A unique data acquisition system has been effectively used to set operating limits which prevent expensive turbine blade damage on a cycling 81 MW steam generating unit. An analysis of system operating data is given, and implementation obstacles are addressed. A load limit has been established to avoid costly turbine blade damage from wet steam conditions due to cycling service. Economical methods are illustrated for overcoming physical instrument limitations, data management and interpretation of system parameters. Potential instrumentation problems and performance codes are addressed     

A study and evaluation of power electronic based adjustable speedmotor drives for air conditioners and heat pumps with an example utilitycase study of the Florida Power and Light Company

The authors present an evaluation, analysis and comparison of several specific power electronic (PE)-based and non-PE based air conditioner and heat pump technologies, and their potential impact for energy savings on the Florida Power and Light Company system. Data and a computer flow chart are provided. Four heat pump models are developed and compared in regard to Florida climates. These models are conventional single-speed, two-speed, variable-speed, and Oak Ridge National Lab variable-speed systems. Some of the results indicate that, generally, the major advantage of PE-based variable-speed variable-capacity heat pumps is due to the higher coefficients of performance and energy efficiency ratios resulting from oversized heat exchangers, and the decrease of cycling losses that result from on/off operation which must occur when capacity exceeds load     

Directional Field Synthesis,Design, and Processing

Direction fields and vector fields play an increasingly important role in computer graphics and geometry processing. The synthesis of directional fields on surfaces, or other spatial domains, is a fundamental step in numerous applications, such as mesh generation, deformation, texture mapping, and many more. The wide range of applications resulted in definitions for many types of directional fields: from vector and tensor fields, over line and cross fields, to frame and vector‐set fields. Depending on the application at hand, researchers have used various notions of objectives and constraints to synthesize such fields. These notions are defined in terms of fairness, feature alignment, symmetry, or field topology, to mention just a few. To facilitate these objectives, various representations, discretizations, and optimization strategies have been developed. These choices come with varying strengths and weaknesses. This report provides a systematic overview of directional field synthesis for graphics applications, the challenges it poses, and the methods developed in recent years to address these challenges.     

Cross‐Collection Map Inference by Intrinsic Alignment of Shape Spaces

Inferring maps between shapes is a long standing problem in geometry processing. The less similar the shapes are, the harder it is to compute a map, or even define criteria to evaluate it. In many cases, shapes appear as part of a collection, e.g. an animation or a series of faces or poses of the same character, where the shapes are similar enough, such that maps within the collection are easy to obtain. Our main observation is that given two collections of shapes whose “shape space” structure is similar, it is possible to find a correspondence between the collections, and then compute a cross‐collection map. The cross‐map is given as a functional correspondence, and thus it is more appropriate in cases where a bijective point‐to‐point map is not well defined. Our core idea is to treat each collection as a point‐sampling from a low‐dimensional shape‐space manifold, and use dimensionality reduction techniques to find a low‐dimensional Euclidean embedding of this sampling. To measure distances on the shape‐space manifold, we use the recently introduced shape differences, which lead to a similar low‐dimensional structure of the shape spaces, even if the shapes themselves are quite different. This allows us to use standard affine registration for point‐clouds to align the shape‐spaces, and then find a functional cross‐map using a linear solve. We demonstrate the results of our algorithm on various shape collections and discuss its properties.     

Privacy aware group based recommender system in multimedia services

Multimedia Tools and Applications - Recommending similar-interest users’ groups in multimedia services is the problem of detecting for each registered user his/her membership to one...