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991.
Microfluidic-based biosensors toward point-of-care detection of nucleic acids and proteins 总被引:1,自引:1,他引:0
Seokheun Choi Michael Goryll Lai Yi Mandy Sin Pak Kin Wong Junseok Chae 《Microfluidics and nanofluidics》2011,10(2):231-247
This article reviews state-of-the-art microfluidic biosensors of nucleic acids and proteins for point-of-care (POC) diagnostics.
Microfluidics is capable of analyzing small sample volumes (10−9–10−18 l) and minimizing costly reagent consumption as well as automating sample preparation and reducing processing time. The merger
of microfluidics and advanced biosensor technologies offers new promises for POC diagnostics, including high-throughput analysis,
portability and disposability. However, this merger also imposes technological challenges on biosensors, such as high sensitivity
and selectivity requirements with sample volumes orders of magnitude smaller than those of conventional practices, false response
errors due to non-specific adsorption, and integrability with other necessary modules. There have been many prior review articles
on microfluidic-based biosensors, and this review focuses on the recent progress in last 5 years. Herein, we review general
technologies of DNA and protein biosensors. Then, recent advances on the coupling of the biosensors to microfluidics are highlighted.
Finally, we discuss the key challenges and potential solutions for transforming microfluidic biosensors into POC diagnostic
applications. 相似文献
992.
Zhengyi Le Yi Ouyang Guanling Chen Fillia Makedon 《Universal Access in the Information Society》2011,10(2):195-205
Pervasive technology has been widely used in assistive environments and aware homes. The issue of how to preserve the privacy
of patients being monitored has been attracting more public concerns. In assistive environments, location data of patients
are collected through sensors for behavior patterns analysis, and they can also be shared among researchers for further research
for early disease diagnosis. However, location information, even though de-identified, also introduces the risk of privacy
leakage. A series of consecutive location samples can be considered as a trajectory of a single person, and this may leak
private information if obtained by malicious users. This paper discusses this problem and proposes a location randomization
algorithm to protect users’ location privacy. Two privacy metrics according to location privacy are defined and used to evaluate
the proposed approach. A method using dynamic mix zones is proposed to confound trajectories of two or more persons. 相似文献
993.
Ensemble of surrogates with recursive arithmetic average 总被引:2,自引:0,他引:2
Xiao Jian Zhou Yi Zhong Ma Xu Fang Li 《Structural and Multidisciplinary Optimization》2011,44(5):651-671
Surrogate models are often used to replace expensive simulations of engineering problems. The common approach is to construct
a series of metamodels based on a training set, and then, from these surrogates, pick out the best one with the highest accuracy
as an approximation of the computationally intensive simulation. However, because the choice of approximate model depends
on design of experiments (DOEs), the traditional strategy thus increases the risk of adopting an inappropriate model. Furthermore,
in the design of complex product system, because of its feature of one-of-a-kind production, acquiring more samples is very
expensive and intensively time-consuming, and sometimes even impossible. Therefore, in order to save sampling cost, it is
a reasonable strategy to take full advantage of all the stand-alone surrogates and then combine them into an ensemble model.
Ensemble technique is an effective way to make up for the shortfalls of traditional strategy. Motivated by the previous research
on ensemble of surrogates, a new technique for constructing of a more accurate ensemble of surrogates is proposed in this
paper. The weights are obtained using a recursive process, in which the values of these weights are updated in each iteration
until the last ensemble achieves a desirable prediction accuracy. This technique has been evaluated using five benchmark problems
and one reality problem. The results show that the proposed ensemble of surrogates with recursive arithmetic average provides
more ideal prediction accuracy than the stand-alone surrogates and for most problems even exceeds the previously presented
ensemble techniques. Finally, we should point out that the advantages of combination over selection are still difficult to
illuminate. We are still using an “insurance policy” mode rather than offering significant improvements. 相似文献
994.
文章对将包含XSS攻击代码的HTTP URLs单词集合分为两部分。按一定粒度分词,运用Apriori算法挖掘攻击模式字符串频繁项集,并在此基础上运用类似Apriori算法思想的PrioriMerge子串合并算法得到攻击模式并统计其频率,实验结果表明算法能有效地挖掘出XSS攻击模式。 相似文献
995.
大型煤炭建工集团管理信息系统 总被引:3,自引:2,他引:1
介绍了中平能化建工集团管理信息系统的总体设计方案、网络及软件平台架构、子系统功能模块组成等。该系统采用智能客户端网络架构和万向接口平台技术,实现了建工企业的全部专用功能以及各个子系统之间的信息交互,使得各机构之间能够有效地协同运作。 相似文献
996.
997.
AUTOSAR是汽车开放系统体系结构,已成为汽车电子软件的工业标准,在汽车电子控制器系统开发过程中具有重要地位,其中AUTOSAR COM通信规范为汽车电子通信系统的构建提供了依据和参考;介绍了AUTOSAR体系架构,对AUTOSAR COM规范基于信号的通信机制及其特有的传输模式切换系统进行了研究,并实现了一种基于AUTOSAR架构的通信系统,试验结果表明该系统能够提供基本通信服务,且符合AUTOSAR COM规范。 相似文献
998.
在新加坡学者Peng-Yong Kong提出的CT-MAC协议研究的基础上,提出了一种修正的UWB通信系统MAC接入协议;算法针对DS-UWB通信物理层,修正了CT-MAC协议原有的最优冲突域计算方法,细化了协议流程;将修正的CT-MAC协议与IEEE802.11 DCF协议分别应用于同一个高速UWB通信系统,对MAC层性能进行仿真分析比较,仿真结果表明:由于CT-MAC协议的最优冲突域范围随带宽增大而减小,因而可保证网络具有更多的并发通信节点;相比较DCF协议,CT-MAC协议更适合DS-UWB通信系统。 相似文献
999.
1000.