12,698 research outputs found
Direct combination: a new user interaction principle for mobile and ubiquitous HCI
Direct Combination (DC) is a recently introduced user interaction principle. The principle (previously applied to desktop computing) can greatly reduce the degree of search, time, and attention required to operate user interfaces. We argue that Direct Combination applies particularly aptly to mobile computing devices, given appropriate interaction techniques, examples of which are presented here. The reduction in search afforded to users can be applied to address several issues in mobile and ubiquitous user interaction including: limited feedback bandwidth; minimal attention situations; and the need for ad-hoc spontaneous interoperation and dynamic reconfiguration of multiple devices. When Direct Combination is extended and adapted to fit the demands of mobile and ubiquitous HCI, we refer to it as Ambient Combination (AC) . Direct Combination allows the user to exploit objects in the environment to narrow down the range of interactions that need be considered (by system and user). When the DC technique of pairwise or n-fold combination is applicable, it can greatly lessen the demands on users for memorisation and interface navigation. Direct Combination also appears to offers a new way of applying context-aware information. In this paper, we present Direct Combination as applied ambiently through a series of interaction scenarios, using an implemented prototype system
Squarepants in a Tree: Sum of Subtree Clustering and Hyperbolic Pants Decomposition
We provide efficient constant factor approximation algorithms for the
problems of finding a hierarchical clustering of a point set in any metric
space, minimizing the sum of minimimum spanning tree lengths within each
cluster, and in the hyperbolic or Euclidean planes, minimizing the sum of
cluster perimeters. Our algorithms for the hyperbolic and Euclidean planes can
also be used to provide a pants decomposition, that is, a set of disjoint
simple closed curves partitioning the plane minus the input points into subsets
with exactly three boundary components, with approximately minimum total
length. In the Euclidean case, these curves are squares; in the hyperbolic
case, they combine our Euclidean square pants decomposition with our tree
clustering method for general metric spaces.Comment: 22 pages, 14 figures. This version replaces the proof of what is now
Lemma 5.2, as the previous proof was erroneou
Cryogenic MMIC low noise amplifiers
Monolithic (MMIC) and discrete transistor (MIC) low noise amplifiers are compared on the basis of performance, cost, and reliability. The need for cryogenic LNA’s for future large microwave arrays for radio astronomy is briefly discussed and data is presented on a prototype LNA for the 1 to 10 GHz range along with a very wideband LNA for the 1 to 60 GHz range. A table of MMIC LNA and mixer designs under development for the frequencies up to 210 GHz is reported and data on cryogenic amplifiers in the 85 to 115 GHz is reviewed. The current status of the topics of transconductance fluctuations and cryogenic noise modeling will be briefly summarized
Investigation of relationships between linears, total and hazy areas, and petroleum production in the Williston Basin: An ERTS approach
The author has identified the following significant results. ERTS-1 imagery in a variety of formats was used to locate linear, tonal, and hazy features and to relate them to areas of hydrocarbon production in the Williston Basin of North Dakota, eastern Montana, and northern South Dakota. Derivative maps of rectilinear, curvilinear, tonal, and hazy features were made using standard laboratory techniques. Mapping of rectilinears on both bands 5 and 7 over the entire region indicated the presence of a northeast-southwest and a northwest-southeast regional trend which is indicative of the bedrock fracture pattern in the basin. Curved lines generally bound areas of unique tone, maps of tonal patterns repeat many of the boundaries seen on curvilinear maps. Tones were best analyzed on spring and fall imagery in the Williston Basin. It is postulated that hazy areas are caused by atmospheric phenomena. The ability to use ERTS imagery as an exploration tool was examined where petroleum and gas are presently produced (Bottineau Field, Nesson and Antelope anticlines, Redwing Creek, and Cedar Creek anticline). It is determined that some tonal and linear features coincide with location of present production in Redwing and Cedar Creeks. In the remaining cases, targets could not be sufficiently well defined to justify this method
Investigation of relationships between linears, tonal and hazy anomalies, and petroleum production in the Williston Basin: An ERTS approach
There are no author-identified significant results in this report
Estimating plasma volume in neonatal Holstein calves fed one or two feedings of a lacteal-based colostrum replacer using Evans blue dye and hematocrit values at various time points.
Twenty-eight Holstein calves were blocked by birth date and randomly assigned to one of two treatments to investigate the effect of colostrum replacer (CR) feeding regimen on plasma volume (PV). Treatments were: 1) one feeding of CR (C1; 3L of reconstituted CR 675 g of powder providing 184.5 g of IgG at birth) or 2) two feedings of CR (C2; 2L of reconstituted CR at birth and 1 L of reconstituted CR at six h). By 6 h of age, all calves had received 3L of CR providing 184.5 g of IgG. Plasma volume was estimated at six, 12, 18, and 24 h after birth using Evans blue dye (EBD). No treatment effects were noted at any time points (P \u3e 0.05). Mean PV for all calves regardless of treatment at six, 12, 18, and 24 h were 78.6, 89.2, 83.9, and 90.7 mL kg-1 of BW, respectively. Plasma volume was correlated with hematocrit (HCT), initial HCT, and treatment. Hematocrit was correlated with PV, initial HCT, and body weight. Hematocrit for six, 12, 18 and 24 h after birth can be predicted with an initial precolostral HCT determination
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