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991.
992.
Roman Rosipal Mark Girolami Leonard J. Trejo Andrzej Cichocki 《Neural computing & applications》2001,10(3):231-243
In this paper, we propose the application of the Kernel Principal Component Analysis (PCA) technique for feature selection
in a high-dimensional feature space, where input variables are mapped by a Gaussian kernel. The extracted features are employed
in the regression problems of chaotic Mackey–Glass time-series prediction in a noisy environment and estimating human signal
detection performance from brain event-related potentials elicited by task relevant signals. We compared results obtained
using either Kernel PCA or linear PCA as data preprocessing steps. On the human signal detection task, we report the superiority
of Kernel PCA feature extraction over linear PCA. Similar to linear PCA, we demonstrate de-noising of the original data by
the appropriate selection of various nonlinear principal components. The theoretical relation and experimental comparison
of Kernel Principal Components Regression, Kernel Ridge Regression and ε-insensitive Support Vector Regression is also provided. 相似文献
993.
本文在ASP中建立与Web数据库的连接,以数据库Student.mdb中的"学生"表为例,阐述本方法操作数据库添加新记录的整个过程,并与传统的方法进行比较和探究。 相似文献
994.
Protein biomarkers in the peripheral blood could potentially be used as early indicators of sepsis and a means to stratify patients for clinical trials. Although individual molecular markers have been proposed for sepsis, none has clinical utility. The global changes in plasma proteins over the clinical course of sepsis have not been characterized using proteomic methods. We used cecal ligation and puncture to induce polymicrobial sepsis in mice and generated plasma protein profiles using 2‐D DIGE of plasma from septic mice and surgical controls. Replicate cohorts (n = 3) of 4–7 animals each were used to identify 62 gel features that changed significantly (Student's t‐test, p<0.05). We identified a suite of plasma proteins that describe uniquely the host plasma response to polymicrobial septic insult. Principal components analysis of protein abundance showed that ~90% of the variability between samples was due to sepsis. In addition to canonical acute phase proteins, we identified proteins that are associated with metabolic changes (e.g. α‐2 HS glycoprotein and zinc α‐2 glycoprotein) consistent with the pathophysiology of sepsis. The panel of sepsis‐associated molecular markers identified herein may prove useful in the diagnosis and categorization of sepsis. 相似文献
995.
基于独立软件级构件的领域软构件体系 总被引:1,自引:0,他引:1
简要地介绍了粒度为独立软件级构件的领域软构件体系的创建过程、系统结构、设计原理及其理论及实用意义。 相似文献
996.
997.
998.
本文给出大型系统在特定指标要求下,系统基
本单元最优组合的一种确定方法.该方法计算简单、容易并且有效,方法的迭代次数是目标
函数的最优值与子系统个数的差,因此,方法在有限步内收敛. 相似文献
999.
Coordination components for collaborative virtual environments 总被引:1,自引:0,他引:1
Alberto B. Raposo Adailton J. A. da Cruz Christian M. Adriano Lo P. Magalhes 《Computers & Graphics》2001,25(6):1025-1039
This paper deals with the behavior of virtual environments from the collaboration point-of-view, in which actors (human or virtual beings) interact and collaborate by means of interdependent tasks. In this sense, actors may realize tasks that are dependent on tasks performed by other actors, while the interdependencies between tasks (through resource management and temporal relations) delineate the overall behavior of a virtual environment. Our main goal is to propose an approach for the coordination of those behaviors. Initially a generic study of possible interdependencies between collaborative tasks is presented, followed by the formal modeling (using Petri Nets) of coordination mechanisms for those dependencies. In order to implement such mechanisms, an architecture of reusable and pluggable coordination components is also introduced. These components are used in an implementation of a multi-user videogame. The presented approach is a concrete step to create virtual societies of actors that collaborate to reach common goals without the risk of getting involved in conflicting or repetitive tasks. 相似文献
1000.
It has been confirmed that adult virgin females ofAnthrenus sarnicus Mroczkowski exhibit a characteristic headstand posture that is associated with the release of a sex pheromone. Volatiles trapped on filter papers suspended above calling females were attractive to adult virgin males when tested in a two-choice target bioassay. Separate aeration extracts of males and females were analyzed by gas chromatography-mass spectrometry and showed that decanol and decyln-butyrate were released by females only. These components were present in approximately equal amounts and accounted for about 90% of the total area of the chromatogram. Decyl butyrate produced an electroantennogram response with a larger response from males than females. Behaviorally, a mixture of 10g of decanol and 10g of decyl butyrate attracted 88% of males and 10g of decyl butyrate alone attracted 82% of males in the bioassay. The role of decyl butyrate as a sex pheromone is convincing, but this is not the case for decanol. 相似文献