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991.
实时动态心电图仪一直是临床广泛应用的医疗器械之一,为使对心电信号(ECG)的采集和初步处理比传统测量方法更加准确可靠,利用USB串行通信和计算机组成了高智能化心电监护仪;该设计以ATmega64及高速16位ADC(AD7677)为核心,利用双极性肢体导联采集微弱电压经放大,带通滤波,工频肌电陷波后通过模数ADC(AD7677)进行采样,而研制了一套高分辨心电信号采集电路,数据最终送入计算机进行处理;结果表明心电信号纯净并可实时显示。 相似文献
992.
程宴 《计算机与数字工程》2008,36(5):167-169
简单介绍ASP技术,探讨基于ASP平台设计与实现的动态网站,重点研究利用ADO访问数据库技术,介绍资源下载系统中资源项管理的实现. 相似文献
993.
本体映射中的概念相似度计算 总被引:1,自引:0,他引:1
本体是概念、属性和关系的集合,本体映射是解决本体异构的最好方法.文中针对目前本体映射过程中概念相似度计算存在的问题,提出一种综合的相似度计算方法.先根据本体中两个概念名称的相似性,选出最相关的概念,减少相似度的计算,然后分别基于概念的属性、实例和关系来计算概念相似度,并进行综合得到概念相似度.在计算属性相似度时,先通过计算属性的信息增益来确定各个属性的优先级,最后只选取几个信息增益大的属性进行相似度的计算,从而减小计算量. 相似文献
994.
Optical coherence tomography (OCT) is an emerging technology for high-resolution cross-sectional imaging of three-dimensional structures. In the past, OCT systems have been used mainly for medical applications, especially ophthalmological diagnostics. As the OCT system is capable of exploring the internal features of an object, the authors apply OCT technology to document security and fingerprint-based biometrics by directly retrieving the two-dimensional information form of a multiple-layer information carrier and internal human body objects. Since a typical depth-resolution of an OCT system is of micrometre scale, an information carrier having a volume of 20 mm times 20 mm times 2 mm could contain 200 mega-pixel images. On other hand, the technologies used in conventional biometrics can be easily fooled and tampered with by using artificial dummies, because these ID features are extracted only from the surface of the skin. Hence the use of OCT to explore the internal biometrics becomes increasingly important. 相似文献
995.
Chiu YH Wu CH Su HY Cheng CJ 《IEEE transactions on pattern analysis and machine intelligence》2007,29(1):28-39
This work proposes a novel approach to translate Chinese to Taiwanese sign language and to synthesize sign videos. An aligned bilingual corpus of Chinese and Taiwanese sign language (TSL) with linguistic and signing information is also presented for sign language translation. A two-pass alignment in syntax level and phrase level is developed to obtain the optimal alignment between Chinese sentences and Taiwanese sign sequences. For sign video synthesis, a scoring function is presented to develop motion transition-balanced sign videos with rich combinations of intersign transitions. Finally, the maximum a posteriori (MAP) algorithm is employed for sign video synthesis based on joint optimization of two-pass word alignment and intersign epenthesis generation. Several experiments are conducted in an educational environment to evaluate the performance on the comprehension of sign expression. The proposed approach outperforms the IBM Model2 in sign language translation. Moreover, deaf students perceived sign videos generated by the proposed method to be satisfactory 相似文献
996.
异步传输模式ATM是国际化电信联盟建议用于宽带综合业务数字网(B-ISDN)的传输模式。容错是提高网络可靠性的主要方法。该文讨论了一种新的容错ATM交换机结构。该结构以Banyan交换机结构为基础,通过增加子交换单元和扩展链路来增加冗余路径的数目,该结构可以容错多个故障,并且冗余路径的数目随着交换机级数的增加而指数增长。同现有文献中其它容错ATM交换机对比分析可以看出,在具有相近的交换元素个数的前提下,建议的交换机提供了更高的容错能力。 相似文献
997.
0 引言智能仪表只要在速度允许的情况下 ,采用软件设计方法来替代部分硬件电路的方式 ,常会使其具有成本低、体积小、功能丰富、可靠性强、精度高等方面的优点。本文介绍SD - 1智能酸碱测量仪中采用的软件技术 ,实践证明效果很好。1 SD -1智能酸碱测量仪酸碱测量仪 (简称 pH计 )广泛应用在石化、电站、冶金、医药、环保和食品等行业 ,常用来测量物质的酸碱度。我们在查阅和参考国内外的资料和产品的基础上 ,成功研制出了SD - 1型智能酸碱监测仪。该仪表具有自诊断、自动确定标样、自动校准、自动调零、溶液温度自动 /手动检测及补… 相似文献
998.
999.
To determine the maximum separation between events for nonrepetitive systems with max and linear constraints, there are the
“iterative tightening from above” (ITA) approach and the “iterative tightening from below” (ITB) approach. Since such systems
can be formulated as systems constrained by min–max inequalities, this paper gives an algorithm named MMIMaxSep for solving min–max inequalities. The algorithm is a generalization and a mathematically elegant reformulation of Yen et
al.’s MaxSeparation algorithm which uses the ITB approach. Our numerical experiments indicate that MMIMaxSep is very efficient. Moreover, MMIMaxSep has a unique advantage of being able to directly handle tree-represented min–max functions, and its complexity is closely
related to the complexity of computing cycle time of min–max functions.
相似文献
Yiping ChengEmail: |
1000.
Chang CW Peng SC Cheng WY Liu SH Cheng HH Huang SY Chang YC 《Proteomics. Clinical applications》2007,1(11):1499-1512
Postsynaptic densities (PSDs), isolated from porcine cerebral cortices, are large disk-shaped aggregates consisting of hundreds of different proteins. To study the protein-protein interactions in such complex supramolecules, we developed a procedure to break up the PSD's overall structure, while preserving some interactions between individual proteins. Using the resulting PSD sample and an indirect immunoabsorption procedure, PSD-95 was isolated along with the α- and β-subunits of calcium calmodulin-dependent protein kinase II (CaMKIIα and CaMKIIβ), α-tubulin, β-tubulin, and Chapsyn110. Similarly, CaMKIIα was isolated along with CaMKIIβ, α-tubulin, β-tubulin, and small amounts of PSD-95. The proteins isolated from PSDs treated with a cleavable bifunctional crosslinking reagent were further subjected to diagonal gel electrophoresis analysis, and the results indicated that CaMKIIα resides next to α-tubulin in the PSD. Overall, the results obtained here suggest that within the PSD, large aggregates of CaMKIIα, CaMKIIβ, α-tubulin, and β-tubulin may occur that indirectly associate with PSD-95 and Chapsyn110. Such a protein organization would allow interactions with F-actin in the cytoplasm and with proteins, such as N-methyl-D-aspartate receptors, which reside on the postsynaptic membrane. Furthermore, it would facilitate binding to proteins such as the various microtubule-associated proteins that reside in the core region of the PSD. 相似文献