移动实时数据库QoS管理和更新事务调度算法

分布式环境下的移动实时数据库服务应用逐渐广泛,但系统负载的不可预测甚至可能的超载使得应用受到限制.系统中事务在低带宽移动环境下竞争有限的系统资源导致重启或夭折,从而给系统带来损失甚至灾难.通过结合时间有效性和值域的有效性提出基于的一种新的衡量系统性能的参数标准,如错过截止期事务的比率、数据新鲜度、CPU利用率去保证QoS,同时提出一种更新事务调度新算法和基于反馈控制的架构去实现.通过仿真实验评估,算法可以从稳定性能和暂态性能保证系统的性能指标不会超过由数据库管理员事先提出的QoS规范.     

Web 事务的弱原子性与正确性标准

事务处理是现代应用系统的基础支撑部件,也是Web服务能否成功支持商务应用的关键技术.但由于环境的高度分布与自治性,传统的可串行化理论已不能再作为Web事务的正确性标准.本文放松了事务的原子性规定,将事务看作由若干原子单元组成的偏序集,并将可串行性扩展为事务的弱可串行性,作为事务的正确性标准.文章最后给出了一个完全分布式的事务并发控制算法,用以实现弱串行性的判定.     

保证数据流融合中处理一致性的事务机制

在分布式实时传感器网络应用中,主要目标之一是保证协作交互的数据流融合任务花费较少的能源代价,能够正确、实时、原子地外化监测区域信息.因此,本文重点研究了分布式传感器网络环境下对多数据流交互处理过程的事务控制机制.首先,定义了传感器网络数据融合过程的协作执行模型.其次,用运控制区域的概念,提出了一种基于系统时间戳的自适应的数据融合交互处理的事务模型及其ACID规则.最后,设计了一种适宜实时环境的数据融合事务的两阶段提交、回滚协议.测试结果分析表明,它能够显著提高采集数据进行事务处理的外化速率,降低了事务的失败率及网络能耗,特别适用于处理间歇、高速的传感器网络外部采集数据.     

基于相似和谨慎等待的移动分布式实时数据库并发控制方法

随着移动计算技术的快速发展,对移动环境下实时事务处理的需求也不断增加.而造成事务重启和阻塞的有限带宽和频繁断开是移动环境下实时系统特有的属性,因此过去针对分布式实时数据库系统的并发控制研究并不能够直接应用在移动分布式实时数据库上.把相似概念和谨慎等待方案与高优先级2阶段锁定(DHP-2PL)结合起来,形成基于相似和谨慎等待的移动分布式实时数据库的并发控制算法,以增加系统并发性,减少重启和阻塞事务的数量,并通过判断事务是否断开而探讨了相应的解决策略,降低了断开问题对系统性能的影响.     

论医学人工智能时代的移动健康终端质量控制

目的：梳理医学人工智能时代的移动健康终端在质量控制方面的要求和问题。方法：查阅国内外监管政策文献,从国外公开的医疗器械审批资料中查询带有移动健康终端的智能化医疗器械在验证与确认环节开展的具体评价工作。结果：移动健康终端的质量评价要求在国内外存在差异,国内在电气安全方面主要参考医用电气设备,而美国可执行其他标准。结论：本文讨论了移动健康终端对人工智能医疗器械的影响,明晰了移动健康终端的质量评价思路,更好地保证基于移动健康终端的人工智能医疗器械的有效性和安全性。     

谈医院药品计算机系统中数据的内部控制

目的:使读者了解如何利用计算机管理药品.方法:从医院药品计算机系统应具备的模块和终端的设置开始,结合分工给予各工作人员权限.结果:只要措施得当方法科学,药品信息就能在系统中安全保存、传输和阅读.结论:本文介绍的方法有一定的借鉴意义.     

网格环境下基于移动Agent的教育资源发现研究

本文使用教育元数据描述规范LOM(Learning Object Management)描述教育资源,并结合移动Agent技术,提出了一种网格环境下基于移动Agent的教育资源发现模型,阐述了教育资源发现过程,并对相关问题进行了讨论.     

正畸固定矫治技术牙移动及支抗控制的发展

正畸治疗的本质就是在力的作用下,通过矫正器使牙齿向正确的方向和位置移动.支抗控制策略事实上很多情况下已经植根于特定的矫治器.按照矫治过程中牙齿移动的方式,可将固定矫治技术分为差动牙移动技术和整体牙移动技术两大类.     

刍议药品检验数据的控制与评价方法

检验工作的最终产品就是药品检验数据,正确、公正的检验结论建立在数据准确性有效控制的基础之上,数据准确性的控制是药品检验的中心工作。药品检验机关应该以合理的频率对检验结果进行内部比对和外部比对,合理、有效地控制药品质量。     

实施“门诊患者医保持卡实时结算”的医院财务内部控制

“门诊患者医保持卡实时结算”是患者门诊医疗费用中,按照医保政策,除患者自付部分之外的费用由医院先期垫付,然后与医保部门结算的模式。本文笔者从财务的角度,详细阐述了持卡实时结算的财务流程、财务风险,并提出了有针对性的财务内部控制措施．以保证持卡实时结算模式下的医院财务安全。     

一种有效的大规模XML数据发布系统中订阅管理方法

随着Internet上XML文档传输量的激增,有效地订阅管理成为整个订阅/发布系统的关键技术之一.把用户海量的订阅条件聚集到一个较小的集合上,这是系统大规模和高效性的要求.对基于XPath树模式的订阅聚集进行系统分析,定义了树模式间的祖孙、包含等语义关系,给出了一个新颖的、优化的树模式包含算法.研究成果能被扩展到XML查询处理等领域.     

网格环境下基于编码机制的数据复制研究

本文提出了基于编码机制的网格数据复制思想,通过对副本数据进行线性分组编码,并将其分散保存到网格存储节点,可形成具有纠删能力的编码子副本组.针对目前热点研究的线性分组编码,探讨基于Cauchy Reed-Solo-mon Code、Tornado Code和Random Linear Code的编码数据复制方案,通过建模手段讨论三者的副本数据访问性能和副本数据可靠性,并与传统的完整数据复制和分块数据复制进行时比分析,证明所提出的编码数据复制有着较优的综合性能.具体实验数据进一步说明,编码副本的编码开销占整个数据复制开销的较小比例,表明编码数据复制是具有可行性的技术方案.     

数据挖掘技术在食品检测数据中的探索

目的：将数据挖掘技术应用到食品安全检测数据中。方法：首先,通过对食品安全检测的原始数据进行选择、清洗、转换和分类等预处理,转换成数据挖掘方法所需要的数据格式。然后,结合不同的数据挖掘方法,研究食品安全在时间、地区、种类等的关联性,以及在时间上的时序性。结果与结论：通过数据挖掘技术,探索食品安全环节潜在的风险点。     

Pushing the Limits of Molecular Crystal Structure Determination From Powder Diffraction Data in High-Throughput Chemical Environments

Crystal structure determination from powder diffraction data (SDPD) using the DASH software package is evaluated for data recorded using transmission capillary, transmission flat plate, and reflection flat plate geometries on a selection of pharmaceutical compounds. We show that transmission capillary geometry remains the best option when crystal structure determination is the primary consideration and, as expected, reflection flat plate geometry is not recommended for SDPD because of preferred orientation effects. However, the quality of crystal structures obtained from transmission plate instruments can be excellent, and the convenience factor for sample preparation, throughput, and retrieval is higher than that of transmission capillary instruments. Indeed, it is possible to solve crystal structures within an hour of a polycrystalline sample arriving in the laboratory, which has clear implications for making small-molecule crystal structures more routinely available to the practicing laboratory medicinal chemist. With appropriate modifications to crystal structure determination software, it can be imagined that SDPD could become a rapid turn-around walk-up analytical service in high-throughput chemical environments.     

A Graphical Approach for Quality Control of Oligonucleotide Array Data

Abstract

In studies of quality control of oligonucleotide array data, one objective is to screen out ineligible arrays. Incomparable arrays (one type of ineligible arrays) arise as the experimental factors are poorly controlled. Due to the high volume of data in gene arrays, examination of array comparability requires special treatments to reduce data dimension without distortion. This paper proposes a graphical approach to address these issues. The proposed approach uses percentile methods to group data, and applies the 2D image plot to display the grouped data. Moreover, an invariant band is employed to quantify degrees of array comparability. We use two publicly available oligonucleotide array datasets from Affymetrix GeneChip System for evaluation. The results demonstrate the utility of our approach to examine data quality and also as an exploratory tool to verify differentially expressed genes selected by vigorous statistical methods.     

Systematic Approaches for Incorporating Control Spots and Data Quality Information to Improve Normalization of cDNA Microarray Data

Background: Normalization and data quality control are two important aspects in microarray data analysis. Proper normalization and data quality control ensure that intensity ratios provide meaningful and accurate measurement of relative gene expression values. Control spots such as spikes and housekeeping genes with known concentrations in two channels are often used for calibrating experimental parameters. They provide valuable information about experimental variation which can be utilized for better normalization. They are also needed for proper normalization in cases that the most of the spots tend to change in one direction. In addition, it is desirable to include information on spot quality. Such information is available in a typical microarray data set, but is not fully utilized by existing normalization methods.

Results: We propose two extensions of the two-way semi-linear model (TW-SLM) for appropriately combining control genes and spot quality information in normalization. The first extension (TW-SLMC) is designed to systematically incorporate control spots in a semi-parametric model to calibrate estimated normalization curves so that the relative fold changes of gene expressions are accurately estimated. Extrapolation is not required in this approach. The second extension (TW-SLMQ) is proposed to incorporate spot quality measure into normalization. This approach down-weights spots with lower quality scores in normalization. These two extensions can be used simultaneously for normalizing a data set. Two microarray data sets are used to demonstrate the proposed methods. Availability: An R based computing package is developed for the proposed methods and available from the corresponding authors.

Contact: Deli Wang: deliwang@uab.edu or Jian Huang: jian-huang@uiowa.edu.     

System for Exchanging Information Among Pharmacists in Different Practice Environments

ObjectivesA system for exchanging patient information among hospital, long-term-care (LTC), and ambulatory care pharmacies is described, and the influence of that system on pharmacist interventions is reported.MethodsStudy sites consisted of three ambulatory care pharmacies, one LTC pharmacy, and one hospital in a small Midwestern city. Meetings were held by clinicians, the investigators, and hospital administrators to plan the information-exchange system. From January through June 1996, patients admitted to the hospital were checked to see if they came from a participating (source) pharmacy; if so, they were randomly assigned to experimental and control groups. The hospital requested preadmission information from the source pharmacy for experimental group patients and did not do so for control patients. After the information arrived, the hospital pharmacists could use it to identify and document drug therapy problems. When an experimental group patient was discharged, the hospital sent information to the appropriate source pharmacy. A total of 156 patients were enrolled in the study.ResultsComplete information transfer occurred for 75% of experimental group patients. Significantly more experimental group patients than control patients had at least one in-hospital pharmacist intervention recorded. Similarly, in the ambulatory care pharmacies (but not the LTC pharmacy) significantly more interventions per patient were documented for the experimental group.ConclusionHospital and ambulatory care pharmacists documented more interventions for patients about whom information had been supplied than for patients for whom that information had not been supplied. No difference in intervention rates was observed for LTC pharmacists, who were already being supplied information by the LTC facilities about patients discharged from the hospital.