1024点高速FFT处理器的FPGA设计与实现

目的 设计满足高速实时信号处理需要的快速傅里叶变换(FFT)处理器。方法采取基-2按频率抽取( DIF)FFT算法,蝶形运算单元采用流水线方式,接收数据采用乒乓操作的方法设计基于现场可编程门阵列(FPGA)的1 024点、32位字长、定点复数FFT处理器。结果在时钟100 MHz下,计算1次1 024点定点FFT耗时约...     

波浪式生物反应器温度控制系统模糊PID算法设计及simulink仿真

目的：设计一种波浪式生物反应器温度控制策略。方法根据波浪式生物反应器温度控制精度及响应速度要求,将传统的比例积分微分（ PID）控制方法与模糊控制方法结合,利用模糊控制方法实时在线调节PID控制的参数,增强温度控制策略对温度的调节性能。结果设计出模糊PID控制器,并与传统PID控制器进行仿真比较。结论模糊PID控制法较传统PID控制法有较小的超调以及较短的稳定时间,说明模糊PID控制具有更高的温度控制调节性能。     

H∞ state‐feedback controller design for continuous‐time nonhomogeneous Markov jump systems

This paper studies the problem of H_∞ state‐feedback controller design for continuous‐time nonhomogeneous Markov jump systems. The time‐varying transition rate matrix in continuous‐time domain is considered to lie in a convex bounded domain of polytopic type. By constructing a parameter‐dependent Lyapunov function and fully considering the information about the rate of change of time‐varying parameters, a new sufficient condition on the existence of an H_∞ state‐feedback controller is provided in the form of a parameter‐dependent matrix inequality. Moreover, based on the structure characteristics of Lyapunov matrix and transition matrix, the parameter‐dependent matrix inequality is converted into a finite set of linear matrix inequalities, which can be readily solved. Two numerical examples are provided to demonstrate the effectiveness of the theoretical results. Copyright © 2016 John Wiley & Sons, Ltd.     

气动调节阀黏滞故障引起的回路振荡消除方法

气动调节阀的黏滞故障是控制回路中常见的故障,由黏滞引起的回路振荡将会破坏整个控制回路的性能。针对不具有定位器的阀门,提出了利用T-S型模糊控制器代替传统的PI控制器来消除此种振荡。该控制器利用阀门黏滞时被控对象的状态信息与控制器输出变化率之间的关系来构建模糊控制的规则。通过对传统PI控制器的积分系数进行修正使得阀门快速移出黏滞区,最终消除黏滞故障对回路的影响。将该算法应用于实际的液位控制回路中,实验结果表明该算法能够较好地消除回路的振荡,且能够适应不同的设定值,具有一定的鲁棒性。     

语言哲学揭示中医概念分析的逻辑框架：以对“肾精”的分析为例

中医概念的分析亟需一个广为接受的逻辑框架,而不是用概念解释概念,或与现代医学的物质简单对应。语言哲学认为语言具有一种逻辑结构,该结构正与世界的逻辑结构一致,即语言是世界的＂逻辑图像＂。本文采纳了该思想,并以对＂肾精＂的分析为例,通过分析古代关于＂肾精＂描述的文献,逐一找出＂肾精＂之所以成为＂肾精＂的若干必要条件,直至形成一个充分条件,希以此例表明这种基于语言哲学的逻辑框架在解析中医核心概念中的有效性。     

HIV misdiagnosis: A root cause analysis leading to improvements in HIV diagnosis and patient care

BackgroundStandard diagnostic testing for HIV infection has traditionally relied on a high sensitivity HIV antibody screening test using an enzyme-linked immunosorbent assay (ELISA) followed by a high specificity antibody confirmatory test such as a Western Blot. Recently several of the screening assays have been enhanced with an ability to identify p24 antigen thereby narrowing the diagnostic window.ObjectivesTo explore the implications of enhanced HIV screening methods that may be leading to HIV misdiagnoses.Study designA patient deemed to be an HIV infected ‘elite controller’ was found to be misdiagnosed when undergoing detailed investigations prior to initiating antiretroviral therapy. A root cause analysis was performed to identify the causative factors of this misdiagnosis. A retrospective review of all “elite controllers” in Alberta, Canada revealed challenges of current HIV testing algorithms.ResultsTechnical and human factors were identified as being causative in this HIV misdiagnosis including (i) high rates of false reactive results on the Abbott ARCHITECT HIV-1&2 COMBO EIA, (ii) human error in reading the initial Western blot, (iii) HIV algorithmic directives in which confirmatory (Western blot) testing was not performed on a repeatedly reactive screen test. The outcome of this analysis identified opportunities for improvement, including implementation of a newly approved (automated) confirmatory assay and improved communication between the clinician and laboratory.ConclusionsHIV testing remains problematic despite significant advances in HIV test performance and algorithm development, presenting new and unexpected issues. Ensuring a high-quality management system including implementation of the latest HIV technologies and algorithms along with human resources and policies are required to minimize the impact of false positive diagnoses, especially in the era of universal screening and ‘test and treat’ recommendations.     

野战用恒温水浴锅的研制

目的：研究一种在野战情况下便于携带、快速展开、用于输液液体加热的野战用恒温水浴锅。方法：应用橡胶水囊作为水箱,结合数字控温器和加热电路实现野战用可折叠便携恒温水箱。恒温箱还可根据水温在2 500 W和1 000 W这2挡加热功率中进行智能切换。结果：经测试,野战用恒温水浴锅可以快速准确加热到设定温度并保持恒定,能够满足野战救治的需求。结论：野战用恒温水浴锅体积小巧、携带方便、操作简便,非常适合在野战条件下应用。     

智能数字温度控制器在设备改造维修中的应用

本文介绍了智能数字温度控制器和利用智能数字温度控制器对几种不同类型的设备进行技术改造的应用实例。     

新型婴儿保温箱的设计

目的:研制具有强制保护电路的婴儿保温箱,以确保婴儿保温箱的工作安全可靠.方法:建立温度数据库,采用Cygnal F005单片机作为智能部件,通过对比的方法准确判断传感器的工作状态;采用双重温度控制系统,确保仪器工作在正常温度范围.仪器发生电路故障可自动切换到强制保护电路,维持保温箱内温度,确保婴儿健康.结果:新型婴儿保温箱的设计确保了电路温度控制精确,工作状态可靠,能够为新生儿提供一个空气洁净、温湿度适宜的舒适安全的环境.结论:婴儿保温箱的性能稳定,精度高,安全可靠,操作方便.     

The application of GIS technology to equitably distribute fieldworker workload in a large, rural South African health survey

A method is presented that has numerous applications to health systems provision in developing countries where limited physical access to primary health care is a major factor contributing to the poor health of populations. An accessibility model within a geographical information system (GIS) is used to predict average inter-homestead walking times and subdivide the study area into units of equal completion time. The method could be used to ergonomically design home-based care and tuberculosis directly observed treatment programmes and inform the siting of health facilities. The paper highlights the use of GIS technology as a powerful tool in developing countries.