Construction experiences with SSC collider dipole magnets atFermilab

Full length and short model SSC (Superconducting Super Collider) 50 mm bore dipoles are being built and tested at Fermilab. The mechanical design of these magnets has been determined from experience with the construction of previous superconducting magnets. Construction experience includes coil fabrication, ground insulation, instrumentation, collaring, and yoke assembly. Fabrication techniques are explained, and construction problems and their solutions are reviewed. The relationship of short to long model construction is discussed     

Therapeutic management in trochanteric fractures

The authors present the management of trochanteric fractures based on 343 fractures treated in Department of Orthopaedics and Trauma in Clinical Hospital of Emergencies of Ia?i for 5 years. The non-operative treatment was used in 17.2% of cases and the conservative methods were plaster immobilization, continuous traction and early mobilization. The surgical treatment was used in 82.8% of cases. The reduction of the fractures was usually possible using closed methods. For fixation, the authors used four types of implants: the 135 degrees blade-plate in 9.2% of cases, the condylar blade plate in 44.7%, Ender nails in 45.4% and DHS in 0.6% of cases. The choice of one of this methods depends on the type of fracture, age of the patient and on his biological status.     

Pricing strategies with reference effects in competitive industries

This paper examines the effect of reference prices on companies operating within competitive industries. We confirm that even with competition, firms optimally price high in the short term to generate a high reference price and then decrease this price over time. Competitors' prices converge toward each other over time, emphasizing the short‐term nature of reference prices. We then show that pricing optimally to take advantage of reference prices generates a positive externality for other firms in an industry, such that competitors may generate higher profit. The longer the focus of a given firm, the more profit the firm generates, but less relative to its competitors. This arises because the externalities created through pricing high to increase reference prices outweigh the benefits of the higher reference prices themselves. If pricing managers are compensated relative to their competition, this suggests that short‐termism may be implicitly encouraged to the detriment of profit.     

Perfect Laplacians for Polygon Meshes

A discrete Laplace‐Beltrami operator is called perfect if it possesses all the important properties of its smooth counterpart. It is known which triangle meshes admit perfect Laplace operators and how to fix any other mesh by changing the combinatorics. We extend the characterization of meshes that admit perfect Laplacians to general polygon meshes. More importantly, we provide an algorithm that computes a perfect Laplace operator for any polygon mesh without changing the combinatorics, although, possibly changing the embedding. We evaluate this algorithm and demonstrate it at applications.     

Representing Animations by Principal Components

In this paper, we present a representation for three-dimensional geometric animation sequences. Different from standard key-frame techniques, this approach is based on the determination of principal animation components and decouples the animation from the underlying geometry. The new representation supports progressive animation compression with spatial, as well as temporal, level-of-detail and high compression ratios. The distinction of animation and geometry allows for mapping animations onto other objects.     

Understanding High Critical Currents in YBa2Cu3O7 Thin Films and Coated Conductors

The main challenges for the success of high temperature superconducting wires, the YBa₂Cu₃O₇ (YBCO) coated conductors (CC), are to avoid the the weak-link problem through the production of biaxially textured films, and to increase the critical current density (J _c) through the introduction of large densities of appropriate defects. To that end, it is essential to understand the pinning mechanisms and their correlation with the microstructure of the CC. We first present a brief overview of the main methods currently used to produce YBCO CC, and we describe the architecture of the YBCO on IBAD fabricated at Los Alamos, summarizing the recent improvements of their structural and superconducting properties. Then, we analyze some aspects of the J _c dependence on temperature and magnetic field (orientation and intensity) for the best CC available, and we compare and contrast the results with those of YBCO thin films on single crystal substrates, in order to determine if the defects controlling the pinning mechanisms are the same in both cases. Our results indicate that over large field and angular ranges J _c on CC is higher than J _c in thin films on SCS.     

Towards an end-to-end airborne remote-sensing system for post-hazard assessment of damage to hyper-critical infrastructure: research progress and needs

The objective of this article is to synthesize research findings and requirements pertaining to development of time-sensitive remote-sensing systems (TSRSS) that support decision-making pertaining to post-hazard assessment of damage to what we define as hyper-critical infrastructure (HCI), based on an aerial imaging approach known as repeat station imaging (RSI). The following TSRSS components are addressed and related findings are reported: (1) understanding information requirements of emergency managers pertaining to damage of HCI; (2) flight planning and data capture requirements for supporting bi-temporal RSI pairs; (3) automatic image registration and shadow classification and normalization routines applied to RSI pairs; (4) damage detection and delineation approach that exploits simple temporal differences in image brightness to automatically, reliably, and robustly delineates new cracks associated with damage; and (5) rapid data and information transfer to emergency managers. The highest priority follow-on research topics are: (1) integrating small unmanned aerial systems (sUAS) with the RSI approach, while enabling multiple view perspectives other than vertical (i.e. nadir pointing) and (2) developing and testing of machine learning routines for automatic identification of damage features from RSI pairs, particularly those captured from integrated sUAS–RSI.