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排序方式: 共有9412条查询结果,搜索用时 15 毫秒
101.
随着计算机及网络的普及,数字化出版成为知识的组织和出版的重要形式。文章尝试利用本体技术,通过扩展标准本体的概念关系集,用于建模教育教学领域的教育资源,将各类教育相关的资源整合成本体知识库,为数字化出版引擎奠定知识基础,实现教育知识和资源的按需聚合与出版。 相似文献
102.
Human face is a complex biomechanical system and non‐linearity is a remarkable feature of facial expressions. However, in blendshape animation, facial expression space is linearized by regarding linear relationship between blending weights and deformed face geometry. This results in the loss of reality in facial animation. To synthesize more realistic facial animation, aforementioned relationship should be non‐linear to allow the greatest generality and fidelity of facial expressions. Unfortunately, few existing works pay attention to the topic about how to measure the non‐linear relationship. In this paper, we propose an optimization scheme that automatically explores the non‐linear relationship of blendshape facial animation from captured facial expressions. Experiments show that the explored non‐linear relationship is consistent with the non‐linearity of facial expressions soundly and is able to synthesize more realistic facial animation than the linear one. 相似文献
103.
Hyeseon LeeAuthor VitaeYeonhee LeeAuthor Vitae Hyunbo ChoAuthor VitaeKwanyoung ImAuthor Vitae Yong Seog KimAuthor Vitae 《Decision Support Systems》2011,52(1):207-216
In a very competitive mobile telecommunication business environment, marketing managers need a business intelligence model that allows them to maintain an optimal (at least a near optimal) level of churners very effectively and efficiently while minimizing the costs throughout their marketing programs. As a first step toward optimal churn management program for marketing managers, this paper focuses on building an accurate and concise predictive model for the purpose of churn prediction utilizing a partial least squares (PLS)-based methodology on highly correlated data sets among variables. A preliminary experiment demonstrates that the presented model provides more accurate performance than traditional prediction models and identifies key variables to better understand churning behaviors. Further, a set of simple churn marketing programs—device management, overage management, and complaint management strategies—is presented and discussed. 相似文献
104.
105.
运用函数连接型神经网络研究 3 8种取代芳烃化合物的分子结构—毒性的定量构效关系 (QSAR) ,计算结果与MLR计算结果比较 ,前者比后者好。与实验结果的线性拟合相关系数 ,FLN所得结果为 0 9561~ 0 9996,MLR所得结果为 0 869~ 0 965。 相似文献
106.
《计算机与应用化学》2000,17(1)
Δ3-1,2,4—噻二唑类化合物具有抑制黄瓜霜霉病毒的杀菌活性。本文用半经验PM3方法对25个该类化合物进行了量子化学计算,并依据原子的净电荷、前沿轨道能级、轨道主要成分及原子在前沿轨道中所占比重等计算结果和多重回归分析讨论了该类化合物的活性部位,为该类化合物结构与活性的研究奠定了理论基础。 相似文献
107.
PANG Luo-jun 《数字社区&智能家居》2008,(15)
作为一种新的软件架构概念和技术,网构软件成为当前软件工程研究领域的焦点之一。然而新的架构技术和运行环境也使得网构软件技术面临着一些新的问题,其中包括网构软件的信息安全性问题。为了实现对网构软件的信息安全保护,本文提出了一种基于信任关系的网构软件安全保护模型,它通过建立网构软件中各软件主体之间的信任关系,达到对网构软件中信息的安全保护目的。 相似文献
108.
A feature relies on three dimensions (space, theme, and time) for its representation. Even though spatiotemporal models have
been proposed, they have principally focused on the spatial changes of a feature. In this paper, a feature-based temporal
model is proposed to represent the changes of both space and theme independently. The proposed model modifies the ISO’s temporal
schema and adds new explicit temporal relationship structure that stores temporal topological relationship with the ISO’s
temporal primitives of a feature in order to keep track feature history. The explicit temporal relationship can enhance query
performance on feature history by removing topological comparison during query process. Further, a prototype system has been
developed to test a proposed feature-based temporal model by querying land parcel history in Athens, Georgia. The result of
temporal query on individual feature history shows the efficiency of the explicit temporal relationship structure.
相似文献
E. Lynn UseryEmail: |
109.
The paper describes results of a longitudinal study of developments in the area of software product and process quality improvement within a Hungarian software company, IQSOFT Ltd. This company has been active in this area since 1993, trying to build, introduce and maintain an efficiently working quality management system which, e.g., fulfils the ISO 9001 requirements, allows steady software process improvement and, at the same time, conforms to company's own needs. Over the last eight years five phases could be distinguished. Each phase is described shortly, following the same structure, namely: basic starting points, key problem areas, literature consulted, activities and design executed, reflections on what happened and why. The lessons resulting from the analysis of this case have been formulated in terms of guidelines. We feel that these are applicable to any low maturity software development organisation embarking on a product or process quality improvement endeavour. These guidelines are developed around a framework containing the basic issues of software production (project management, technical processes and products). The guidelines advocate a careful step-by-step development of definitions, quality characteristics, and metrics related to these objects while at the same time developing and introducing the associated process. 相似文献
110.
以logistic模型为基础 ,以时间因子为媒介 ,推导出一个能准确描述植物病害I-S的logistic衍生模型。通过对油松落针病、花生锈病、烟草黄瓜花叶病和小麦赤霉病等多组I-S关系数据的实例验证与比较分析 ,显示出这一模型具有较强的数据拟合能力和广泛的适用性。Logistic衍生模型尚可应用于林木胸径与材积(D -V)关系、径与树高(D -H)关系以及生物量预估等项研究。此外 ,还提出一个具有普遍指导意义的通用模型 相似文献