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31.
An exploratory, comparative survey design was used to describe and compare similarities and differences in perception of caring behaviors between hospitalized antepartum and short-stay postpartum patients. Forty-two patients completed the 63-item Caring Behavior Assessment instrument (CBA). The scale, based on Watson's theory of caring, contains seven categories. There were no statistically significant differences in age, education, gravida, or para between the two groups. Significantly more women in the postpartum group were married. There were no statistically significant differences or correlations in the total CBA scores and the demographic variables. No statistically significant differences in total CBA scores were found between antepartum participants and postpartum participants. These findings corroborate the results of "caring" studies in other patient populations, that satisfying basic needs--that is, evidence of technical knowledge and skills--is more important to patients than meeting higher order needs. 相似文献
32.
33.
Schultz T Kindlmann GL 《IEEE transactions on visualization and computer graphics》2010,16(6):1595-1604
Symmetric second-order tensor fields play a central role in scientific and biomedical studies as well as in image analysis and feature-extraction methods. The utility of displaying tensor field samples has driven the development of visualization techniques that encode the tensor shape and orientation into the geometry of a tensor glyph. With some exceptions, these methods work only for positive-definite tensors (i.e. having positive eigenvalues, such as diffusion tensors). We expand the scope of tensor glyphs to all symmetric second-order tensors in two and three dimensions, gracefully and unambiguously depicting any combination of positive and negative eigenvalues. We generalize a previous method of superquadric glyphs for positive-definite tensors by drawing upon a larger portion of the superquadric shape space, supplemented with a coloring that indicates the quadratic form (including eigenvalue sign). We show that encoding arbitrary eigenvalue magnitudes requires design choices that differ fundamentally from those in previous work on traceless tensors that arise in the study of liquid crystals. Our method starts with a design of 2-D tensor glyphs guided by principles of scale-preservation and symmetry, and creates 3-D glyphs that include the 2-D glyphs in their axis-aligned cross-sections. A key ingredient of our method is a novel way of mapping from the shape space of three-dimensional symmetric second-order tensors to the unit square. We apply our new glyphs to stress tensors from mechanics, geometry tensors and Hessians from image analysis, and rate-of-deformation tensors in computational fluid dynamics. 相似文献
34.
Schultz Thomas Theisel Holger Seidel Hans-Peter 《IEEE transactions on visualization and computer graphics》2010,16(1):109-119
Crease surfaces are two-dimensional manifolds along which a scalar field assumes a local maximum (ridge) or a local minimum (valley) in a constrained space. Unlike isosurfaces, they are able to capture extremal structures in the data. Creases have a long tradition in image processing and computer vision, and have recently become a popular tool for visualization. When extracting crease surfaces, degeneracies of the Hessian (i.e., lines along which two eigenvalues are equal) have so far been ignored. We show that these loci, however, have two important consequences for the topology of crease surfaces: First, creases are bounded not only by a side constraint on eigenvalue sign, but also by Hessian degeneracies. Second, crease surfaces are not, in general, orientable. We describe an efficient algorithm for the extraction of crease surfaces which takes these insights into account and demonstrate that it produces more accurate results than previous approaches. Finally, we show that diffusion tensor magnetic resonance imaging (DT-MRI) stream surfaces, which were previously used for the analysis of planar regions in diffusion tensor MRI data, are mathematically ill-defined. As an example application of our method, creases in a measure of planarity are presented as a viable substitute. 相似文献
35.
In this work, we describe an autonomous mobile robotic system for finding, investigating, and modeling ambient noise sources
in the environment. The system has been fully implemented in two different environments, using two different robotic platforms
and a variety of sound source types. Making use of a two-step approach to autonomous exploration of the auditory scene, the
robot first quickly moves through the environment to find and roughly localize unknown sound sources using the auditory evidence
grid algorithm. Then, using the knowledge gained from the initial exploration, the robot investigates each source in more
depth, improving upon the initial localization accuracy, identifying volume and directivity, and, finally, building a classification
vector useful for detecting the sound source in the future. 相似文献
36.
Gert A. Schultz 《国际水》2013,38(1):96-109
Abstract Presently a change of paradigm in the field of planning and operation of water management schemes can be observed. The introduction of the principle of sustainable development by the United Nations and the principle of integrated river basin management postulated by the European Union play a major role in this context. Introduction of these new principles requires development of new planning tools, which in turn require a much better data basis than available hitherto. This paper deals with new data types already partly available now, partly to be expected to be developed in the medium-range future. The present data situation is discussed, along with the obvious deficits of conventional data. New data types will not be limited to point measurements, but rather must comprise information covering large areas with a higher resolution in time and space than presently available. Remote sensing data will play a more important role in the future. Furthermore, digital maps, digital elevation models, etc. are also of growing importance and will be processed, together with remote sensing and other data, within Geographical Information Systems of future generations also exposing the potential for working with multi-temporal imagery. In the paper it is shown that in the future more accurate data will be available, not only in terms of data quality, but also resolution in time and space. It is shown how the new types of hydrometeorological data postulate new types of hydrological models. Here, distributed system models are of growing importance. Furthermore, it is shown how the combination of remote sensing with other information leads to new data types that allow integrated planning of water resources systems. The potential of real time data is highlighted, particularly in the context of real time operation of water resources systems, especially for flood control. The potential of large-scale data schemes in the context of regional and continental water management schemes is discussed. Global atmospheric models coupled to hydrological models are discussed, and their potential to consider long-distance effects of certain phenomena (e.g., El Niño) are mentioned. For sustainable development of water resources, the potential of long-term data prediction scenarios is evaluated, and an example of this principle for planning future water supply systems is presented. The paper ends with a vision of future developments in planning water management schemes on the basis of new data types 相似文献
37.
Olivier Noel Houssein Awada Gilles Castelein Maurice Brogly Jacques Schultz 《The Journal of Adhesion》2006,82(7):649-669
The atomic force microscope (AFM) can be used to perform surface force measurements in the quasi-static mode (cantilever is not oscillating) to investigate nanoscale surface properties. Nevertheless, there is still a lack of literature proposing a complete systematic and rigorous experimental procedure that enables one to obtain reproducible and significant quantitative data. This article focuses on the fundamental experimental difficulties arising when making force curve measurements with the AFM in air. On the basis of this AFM calibration procedure, quantitative assessment values were used to determine, in situ, SAM (or Self Assembled Monolayer)-tip thermodynamic work of adhesion at a local scale, which have been found to be in good agreement with quoted values. Finally, determination of surface energies of functionalised silicon wafers (as received, CH3, OH functionalised silicon wafers) with the AFM (at a local scale) is also proposed and compared with the values obtained by wettability (at a macroscopic scale). In particular, the effect of the capillary forces is discussed. 相似文献
38.
As the year 2000 draws near, solutions to the Year 2000 (Y2K) problem seem both abundant and elusive. At this late date, Y2K problems require fast, flawless solutions. This article sets forth a practical work plan for assessing and correcting problems in existing application programs 相似文献
39.
E.Eugene Schultz 《Network Security》2004,2004(1):6-9
Introduction
After initially releasing Windows 2000 (W2K) in February 2000, Microsoft touted it as a secure operating system, one that was far improved over its predecessor, Windows NT(WNT). Yet even before Microsoft released W2K the software giant announced that it would release Service Pack 1 (SP1) for this operating system. The information security community immediately wondered whether the claims about the much improved security in W2K were true; many events and findings since then have reinforced this doubt. After a reign of three years as Microsoft's flagship operating system, last year Microsoft rolled out its newest server operating system, Windows Server 2003 (WS2003), signaling the end of an era for the W2K operating system. Windows XP (WXP) had already supplanted W2K Professional as the newest workstation operating system several years before. This is not to say that nobody uses W2K any more—to the contrary. But as W2K continues to increasingly take a proverbial back seat to newer Microsoft operating systems, now is a good time to take a retroactive look at W2K from a security viewpoint. Was it a success from a security perspective? What were its major failings and why? This paper addresses these issues. 相似文献40.
The academic literature in 2000 presented a procedure for solving the job-shop-scheduling problem of minimizing L max. The iterative-adaptive simulation-based procedure is shown here to perform well on large-scale problems. However, there is potential for improvement in closing the gap between best-known solutions and the lower bound. In the present paper, a simulated annealing post-processing procedure is presented and evaluated on large-scale problems. A new neighbourhood structure for local searches in the job-shop scheduling problem is developed. The procedure is also evaluated using benchmark problems and new upper bounds are established. 相似文献