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991.
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We present a novel mesh denoising and smoothing method in this paper. Our approach starts by estimating the principal curvatures
and mesh saliency value for each vertex. Then, we calculate the uniform principal curvature of each vertex based on the weighted
average of local principal curvatures. After that, we use the weighted bi-quadratic Bézier surface to fit the neighborhood
of each vertex using the least-square method and obtain the new vertex position by adjusting the parameters of the fitting
surface. Experiments show that our smoothing method preserves the geometric feature of the original mesh model efficiently.
Our approach also prevents the volume shrinkage of the input mesh and obtains smooth boundaries for non-closed mesh models. 相似文献
994.
Data discretization unification 总被引:2,自引:1,他引:1
995.
Installed base is a measure describing the number of units of a particular system actually in use. To maintain the performance of the installed units, spare parts inventory control is extremely important and becomes very challenging when the installed base changes over time. This problem is often encountered when a manufacturer starts to deliver a new product to customers and agrees to provide spare parts to replace failed units in the future. To cope with the resulting non-stationary stochastic maintenance demand, a spare parts control strategy needs to be carefully developed. The goal is to ensure that timely replacements can be provided to customers while minimizing the overall cost for spare parts inventory control. This paper provides a model for the aggregate maintenance demand generated by a product whose installed base grows according to a homogeneous Poisson process. Under a special case where the product’s failure time follows the exponential distribution, the closed form solutions for the mean and variance of the aggregate maintenance demand are obtained. Based on the model, a dynamic (Q, r) restocking policy is formulated and solved using a multi-resolution approach. Two numerical examples are provided to demonstrate the application of the proposed method in controlling spare parts inventory under a service level constraint. Simulation is utilized to explore the effectiveness of the multi-resolution approach. 相似文献
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1000.
A structured P2P network based on the small world phenomenon 总被引:1,自引:0,他引:1
In this paper, we propose a new structured P2P overlay network, named SW-Uinta(small-world). In order to reduce the routing
latency, we firstly construct the Uinta network in which both physical characteristics of network and data semantic are considered.
Furthermore, based on Uinta, a nondeterministic caching strategy is employed to allow for poly-logarithmic search time while
having only a constant cache size. Compared with the deterministic caching strategy proposed by previous P2P systems, the
nondeterministic caching strategy can reduce communication overhead for maintaining the routing cache table. Cache entries
in the cache table of peer nodes can be updated by subsequent queries rather than only by running stabilization periodically.
In the following, a novel cache replacement scheme, named the SW cache replacement scheme, is used to improve lookup performance,
which has proved to satisfy the small-world principle. So we call this network SW-Uinta(small-world). After that, according
to the theoretical analysis, it can be proved that SW-Uinta(small-world) can get O((log 2
N)/k) search time with O(k) cache size. Lastly, the performance of SW-Uinta(small-world) is compared with those of other structured P2P networks such
as Chord and Uinta. It shows that SW-Uinta(small-world) can achieve improved object lookup performance and reduce maintenance
cost.
相似文献
Hai Jin (Corresponding author)Email: |