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51.
This work demonstrates in practical terms the evolutionary concepts and computational applications of Parametric Curves. Specific cases were drawn from higher order parametric Bezier curves of degrees 2 and above. Bezier curves find real life applications in diverse areas of Engineering and Computer Science, such as computer graphics, robotics, animations, virtual reality, among others. Some of the evolutionary issues explored in this work are in the areas of parametric equations derivations, proof of related theorems, first and second order calculus related computations, among others. A Practical case is demonstrated using a graphical design, physical hand sketching, and programmatic implementation of two opposite-faced handless cups, all evolved using quadratic Bezier curves. The actual drawing was realized using web graphics canvas programming based on HTML 5 and JavaScript. This work will no doubt find relevance in computational researches in the areas of graphics, web programming, automated theorem proofs, robotic motions, among others.  相似文献   
52.
Health care executives across the country, faced with intense competition, are being forced to consider drastic cost cutting measures as a matter of survival. The entire health care industry is under siege from boards of directors, management and others who encourage health care systems to take actions ranging from strategic acquisitions and mergers to simple "downsizing" or "rightsizing," to improve their perceived competitive positions in terms of costs, revenues and market share. In some cases, management is poorly prepared to work within this new competitive paradigm and turns to consultants who promise that following their methodologies can result in competitive advantage. One favored methodology is reengineering. Frequently, cost cutting attention is focused on the materials management budget because it is relatively large and is viewed as being comprised mostly of controllable expenses. Also, materials management is seldom considered a core competency for the health care system and the organization performing these activities does not occupy a strongly defensible position. This paper focuses on the application of a reengineering methodology to healthcare materials management.  相似文献   
53.
Up to now, the quality of life of children and adolescents with psychiatric disorders has rarely been investigated. Not many suitable instruments are available. A new one is the "Inventory for the Assessment of the Quality of Live in Children and Adolescents" presented here. Objectives and underlying conceptual assumptions are discussed, followed by an explanation of the instrument itself (questionnaires, rating scales, etc.). Finally, experiences with the application of the instrument are reported together with initial empirical results from a clinical sample and a sample of high school students. These indicate that the instrument usefully assesses clinically relevant information about the quality of life of the patients. A broader empirical analysis of this method is being prepared.  相似文献   
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55.
Necrotizing enterocolitis (NEC) and midgut volvulus (MGV) often are associated with extensive bowel necrosis. These cases may require extensive enterectomy and the formation of high or multiple stomas, and frequently are complicated by short bowel syndrome, excessive fluid losses, fistulas, stenosis, and skin breakdown. This report describes a "clip and drop-back" technique, followed by delayed anastomosis performed 48 to 72 hours later. The technique was successful in five severely ill infants (3 NEC, 2 MGV) with extensive necrosis, bowel perforation(s), and peritonitis, who required either a high stoma near the ligament of Treitz or multiple resections and enterostomies. This method removes obvious necrotic perforated bowel, controls contamination, avoids stomas (and their inherent complications in this age group), and preserves bowel length. All five babies survived. The technique is a useful addition to the pediatric surgeon's operative armamentarium in selective cases.  相似文献   
56.
A new axiomatic system OST of operational set theory is introduced in which the usual language of set theory is expanded to allow us to talk about (possibly partial) operations applicable both to sets and to operations. OST is equivalent in strength to admissible set theory, and a natural extension of OST is equivalent in strength to ZFC. The language of OST provides a framework in which to express “small” large cardinal notions—such as those of being an inaccessible cardinal, a Mahlo cardinal, and a weakly compact cardinal—in terms of operational closure conditions that specialize to the analogue notions on admissible sets. This illustrates a wider program whose aim is to provide a common framework for analogues of large cardinal notions that have appeared in admissible set theory, admissible recursion theory, constructive set theory, constructive type theory, explicit mathematics, and systems of recursive ordinal notations that have been used in proof theory.  相似文献   
57.
The discovery of meaningful parts of a shape is required for many geometry processing applications, such as parameterization, shape correspondence, and animation. It is natural to consider primitives such as spheres, cylinders and cones as the building blocks of shapes, and thus to discover parts by fitting such primitives to a given surface. This approach, however, will break down if primitive parts have undergone almost‐isometric deformations, as is the case, for example, for articulated human models. We suggest that parts can be discovered instead by finding intrinsic primitives, which we define as parts that posses an approximate intrinsic symmetry. We employ the recently‐developed method of computing discrete approximate Killing vector fields (AKVFs) to discover intrinsic primitives by investigating the relationship between the AKVFs of a composite object and the AKVFs of its parts. We show how to leverage this relationship with a standard clustering method to extract k intrinsic primitives and remaining asymmetric parts of a shape for a given k. We demonstrate the value of this approach for identifying the prominent symmetry generators of the parts of a given shape. Additionally, we show how our method can be modified slightly to segment an entire surface without marking asymmetric connecting regions and compare this approach to state‐of‐the‐art methods using the Princeton Segmentation Benchmark.  相似文献   
58.
Cartoon animation, image warping, and several other tasks in two‐dimensional computer graphics reduce to the formulation of a reasonable model for planar deformation. A deformation is a map from a given shape to a new one, and its quality is determined by the type of distortion it introduces. In many applications, a desirable map is as isometric as possible. Finding such deformations, however, is a nonlinear problem, and most of the existing solutions approach it by minimizing a nonlinear energy. Such methods are not guaranteed to converge to a global optimum and often suffer from robustness issues. We propose a new approach based on approximate Killing vector fields (AKVFs), first introduced in shape processing. AKVFs generate near‐isometric deformations, which can be motivated as direction fields minimizing an “as‐rigid‐as‐possible” (ARAP) energy to first order. We first solve for an AKVF on the domain given user constraints via a linear optimization problem and then use this AKVF as the initial velocity field of the deformation. In this way, we transfer the inherent nonlinearity of the deformation problem to finding trajectories for each point of the domain having the given initial velocities. We show that a specific class of trajectories — the set of logarithmic spirals — is especially suited for this task both in practice and through its relationship to linear holomorphic vector fields. We demonstrate the effectiveness of our method for planar deformation by comparing it with existing state‐of‐the‐art deformation methods.  相似文献   
59.
Lennart Åqvist (1992) proposed a logical theory of legal evidence, based on the Bolding-Ekelöf of degrees of evidential strength. This paper reformulates Åqvist's model in terms of the probabilistic version of the kappa calculus. Proving its acceptability in the legal context is beyond the present scope, but the epistemological debate about Bayesian Law isclearly relevant. While the present model is a possible link to that lineof inquiry, we offer some considerations about the broader picture of thepotential of AI & Law in the evidentiary context. Whereas probabilisticreasoning is well-researched in AI, calculations about the threshold ofpersuasion in litigation, whatever their value, are just the tip of theiceberg. The bulk of the modeling desiderata is arguably elsewhere, if one isto ideally make the most of AI's distinctive contribution as envisaged forlegal evidence research.  相似文献   
60.
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