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排序方式: 共有3712条查询结果,搜索用时 15 毫秒
51.
Michael Wand Alexander Berner Martin Bokeloh Philipp Jenke Arno Fleck Mark Hoffmann Benjamin Maier Dirk Staneker Andreas Schilling Hans-Peter Seidel 《Computers & Graphics》2008,32(2):204-220
This paper describes a new out-of-core multi-resolution data structure for real-time visualization, interactive editing and externally efficient processing of large point clouds. We describe an editing system that makes use of the novel data structure to provide interactive editing and preprocessing tools for large scanner data sets. Using the new data structure, we provide a complete tool chain for 3D scanner data processing, from data preprocessing and filtering to manual touch-up and real-time visualization. In particular, we describe an out-of-core outlier removal and bilateral geometry filtering algorithm, a toolset for interactive selection, painting, transformation, and filtering of huge out-of-core point-cloud data sets and a real-time rendering algorithm, which all use the same data structure as storage backend. The interactive tools work in real-time for small model modifications. For large scale editing operations, we employ a two-resolution approach where editing is planned in real-time and executed in an externally efficient offline computation afterwards. We evaluate our implementation on example data sets of sizes up to 63 GB, demonstrating that the proposed technique can be used effectively in real-world applications. 相似文献
52.
Nonparametric Bayesian Image Segmentation 总被引:1,自引:0,他引:1
Image segmentation algorithms partition the set of pixels of an image into a specific number of different, spatially homogeneous
groups. We propose a nonparametric Bayesian model for histogram clustering which automatically determines the number of segments
when spatial smoothness constraints on the class assignments are enforced by a Markov Random Field. A Dirichlet process prior
controls the level of resolution which corresponds to the number of clusters in data with a unique cluster structure. The resulting posterior is efficiently
sampled by a variant of a conjugate-case sampling algorithm for Dirichlet process mixture models. Experimental results are
provided for real-world gray value images, synthetic aperture radar images and magnetic resonance imaging data. 相似文献
53.
In this work we examine the influence of the diffusive motion of vortices in highly anisotropic high-Tc superconductors near the Berezinskii-Kosterlitz-Thouless (BKT) transition temperature T
bkt
on the spin-lattice relaxation rate T
1
–1
.We find a jump in T
1
–1
at the temperature T
bkt
. 相似文献
54.
Optimized Photoinitiator for Fast Two‐Photon Absorption Polymerization of Polyester‐Macromers for Tissue Engineering 下载免费PDF全文
55.
56.
Gian Luigi Angrisani Piriya Taptimthong Susanne Elisabeth Thürer Christian Klose Hans Jürgen Maier Marc Christopher Wurz Kai Möhwald 《Advanced Engineering Materials》2018,20(9)
57.
Orphan detection in distributed systems is a well-researched field for which many solutions exist. These solutions exploit well defined parent-child relationships given in distributed systems. But they are not applicable in mobile agent systems, since no similar natural relationship between agents exist. Thus new protocols have to be developed. In this paper one such protocol for controlling mobile mobile agents and for orphan detection is presented. The shadow approach presented in this paper uses the idea of a placeholder (shadow) which is assigned by the agent system to each new agent. This defines an artificial relationship between agents and shadow. The shadow records the location of all dependent agents. Removing the root shadow implies that all dependent agents are declared orphan and are eventually be terminated. We introduce agent proxies that create a path from shadow to every agent. In an extension of the basic protocol we additionally allow the shadow to be mobile.The shadow approach can be used for termination of groups of agents even if the exact location of each single agent is not known. 相似文献
58.
Maurus Biedermann Konrad Grob Carlo Mariani Joachim P. Schmidt 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1996,202(3):199-204
Adulteration of expensive edible oils, such as olive oil, often involves desterolized oils in order to render the adulteration undetectable. Sunflower oil contains characteristic 7-sterols, which are readily removed upon strong bleaching. It is shown that these 7-sterols do not primarily dehydrate (as do 5-sterols), but isomerize to 8(14)- and 14-sterols. These compounds can be analysed by LC on silica gel or GC on capillary columns with stationary phases of intermediate to high polarity. 相似文献
59.
METHOD: The time from first diagnosis of primary multiple metastatic prostate carcinoma until progression and until death in patients less than 60 years old under two different therapeutic regimens was evaluated. RESULTS: In the group with pure androgen deprivation (n = 21), the mean time until progression was 11.3 (6-55) months, the mean survival time being 21.4 (11-75) months. In the group with androgen deprivation plus cytostatic therapy (n = 10), progression was noted after 26.7 (15-77) months with a medium survival time of 26.2 (16-82) months. CONCLUSION: The data argue in favor of changing the usual treatment strategy to combination therapy in "young' patients with primary metastatic prostatic cancer. 相似文献
60.
Even though there is abundant literature on successful cases of organizations applying knowledge management (KM) measures,
many KM initiatives have failed to achieve their knowledge and business goals. In order to foster decisions about the design
of such initiatives, information is required on success factors and barriers when selecting KM measures. Multi agent-based
simulation (MABS) is suggested as instrument to investigate potential effects of KM measures on dependent variables such as
sharing of knowledge in organizations or business performance. For such a simulation, the concept of knowledge sharing, influencing
factors and their impact on business and knowledge goals are modeled based on an extensive multi-disciplinary literature survey.
An extensive domain model is operationalized in a simulation model which is then further simplified and implemented in a MABS
tool used for a series of experiments contrasting results with/without KM measures, specifically skill and experience management.
Skill management is found highly sensitive with respect to conditions of application and has no significant impact on knowledge
or business goals. Experience management positively impacts knowledge and business goals. Personal documentation leads to
specialist, project debriefings to generalist knowledge workers. Finally, the paper discusses the simulation’s limitations
and further areas of application. 相似文献