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Cyclostationary signature design for common control channel of cognitive radio 被引量:1
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作者 QI Yuan PENG Tao +1 位作者 WANG Wen-bo LUO Shi-feng 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2009年第2期42-46,共5页
Embedding specific signatures in transmitted signals for identifying common control channels of cognitive radio are addressed in research laboratories because availability of the spectrum occupied by the common contro... Embedding specific signatures in transmitted signals for identifying common control channels of cognitive radio are addressed in research laboratories because availability of the spectrum occupied by the common control channel might change in time.A novel solution to embed a unique cyclostationary signature for the common control channel of cognitive radio is proposed in this article.Based on linear periodically time-variant transformation(LPTV)model,the cyclic autocorrelation expression of the proposed signature is derived,which characterizes its cyclostationarity.Analysis of the cyclostationary signature is presented considering effects of additive white Gaussian noise(AWGN)and multiplath channels.Simulation results illustrating the reliability of signatures are given. 展开更多
关键词 cyclostationary signature spectrum sensing cognitive radio common control channel
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Frequency compensation control method for opposedpiston two-stroke folded-cranktrain engine's common rail system by loop-shaping theory
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作者 左哲 张哲瑜 +2 位作者 钱李龙 张付军 岳广臣 《Journal of Beijing Institute of Technology》 EI CAS 2016年第2期194-201,共8页
A frequency compensation control method for the opposed-piston two-stroke folded-cranktrain( OPFC) diesel engine's common rail system is presented as a result of the study of the loop-shaping theory. A common rail ... A frequency compensation control method for the opposed-piston two-stroke folded-cranktrain( OPFC) diesel engine's common rail system is presented as a result of the study of the loop-shaping theory. A common rail working process and the classical frequency control theory are combined to construct a frequency restriction of common rail pressure. A frequency compensator is utilized to improve the robustness of multiplicative perturbations and disturbance. The loop-shaping method has been applied to design the common rail pressure controller of the OPFC diesel engine. Simulation and bench test results show that in the condition of perturbation that comes from the effect of injection,multi-injection,fuel pumping of a pre-cylinder,and instantaneous pressure fluctuation,the controller indicates high precision. Compared with the original controller,this method improves the control precision by 67. 3%. 展开更多
关键词 robust control opposed-piston two-stroke folded-cranktrain diesel engine loop-sha-ping frequency compensator common rail control
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Design of bounded feedback controls for linear dynamical systems by using common Lyapunov functions
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作者 Igor Ananievskii Nickolai Anokhin Alexander Ovseevich 《Theoretical & Applied Mechanics Letters》 CAS 2011年第1期66-68,共3页
For a linear dynamical system,we address the problem of devising a bounded feedback control,which brings the system to the origin in finite time.The construction is based on the notion of a common Lyapunov function.It... For a linear dynamical system,we address the problem of devising a bounded feedback control,which brings the system to the origin in finite time.The construction is based on the notion of a common Lyapunov function.It is shown that the constructed control remains effective in the presence of small perturbations. 展开更多
关键词 linear control system feedback control bounded control common Lyapunov function
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CAP1400安全级仪控系统共因失效应对和分析验证
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作者 史国宝 王海涛 +5 位作者 王志超 任文星 吴雪雯 刘立欣 张国胜 樊普 《核安全》 2026年第1期51-59,共9页
目前,数字化仪控技术已越来越多地应用于核电厂,数字化仪控系统由于设计或使用不当引起的共因故障可能影响核电厂安全。国内外相关导则提出了仪控系统纵深防御和多样性(D3)设计要求,需要论证安全分析报告第15章始发事件叠加安全级仪控... 目前,数字化仪控技术已越来越多地应用于核电厂,数字化仪控系统由于设计或使用不当引起的共因故障可能影响核电厂安全。国内外相关导则提出了仪控系统纵深防御和多样性(D3)设计要求,需要论证安全分析报告第15章始发事件叠加安全级仪控系统共因失效后核电厂的安全性。CAP1400设置了多样化驱动系统(DAS),包含6个自动功能和10个手动功能,定性和定量评估表明多样化程度高;针对D3分析建立了分析方法体系,开展事故分析,结果表明所有事故都能得到缓解,DAS系统具有充分的纵深防御能力。 展开更多
关键词 数字化仪控 共因故障 纵深防御和多样性分析 CAP1400
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大规模海上风电经柔直送出系统的受端功率协调控制策略
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作者 彭穗 李峰 +3 位作者 黄小威 唐玉烽 彭发喜 王彦峰 《南方电网技术》 北大核心 2026年第1期131-142,共12页
基于模块化多电平换流器(modular multilevel converter,MMC)的柔性直流输电技术因其效率高、控制灵活、便于扩展至多端系统等优势,逐渐成为海上风电并网的重要方式。海上风电场送出的有功功率具有随机性和波动性,大范围的功率波动可能... 基于模块化多电平换流器(modular multilevel converter,MMC)的柔性直流输电技术因其效率高、控制灵活、便于扩展至多端系统等优势,逐渐成为海上风电并网的重要方式。海上风电场送出的有功功率具有随机性和波动性,大范围的功率波动可能造成受端换流站功率越限、直流电压越限和交直流系统功率回环等问题。为此,提出了两种适用于大规模海上风电经柔直送出系统的受端功率协调控制策略。首先,介绍了送出系统基本结构和MMC控制策略。然后,设计了受端有功功率自均衡控制策略和共用外环的定直流电压控制,两种策略具有不同的技术特点,但均能够实现多个受端换流站之间的有功功率合理分配,从而避免不必要的功率越限、电压越限和功率回环等问题。最后,利用PSCAD/EMTDC仿真验证了两种控制策略的有效性。 展开更多
关键词 风电场 功率协调控制 有功功率自均衡 共用外环
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迈腾B8L汽车信号喇叭的常见故障及检修策略
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作者 刘晓攀 《内燃机与配件》 2026年第2期92-94,共3页
汽车信号喇叭作为车辆主动安全与通信的关键部件,其工作可靠性直接关系到行车安全与驾驶体验。迈腾B8L车型搭载的电子控制喇叭系统集成度高、控制逻辑复杂,实践中常出现喇叭不响、音质异常、间歇性工作等故障。为提高此类故障的诊断效... 汽车信号喇叭作为车辆主动安全与通信的关键部件,其工作可靠性直接关系到行车安全与驾驶体验。迈腾B8L车型搭载的电子控制喇叭系统集成度高、控制逻辑复杂,实践中常出现喇叭不响、音质异常、间歇性工作等故障。为提高此类故障的诊断效率与维修准确性,本文系统阐述迈腾B8L信号喇叭的系统结构、控制原理与电路特点,结合典型维修案例,归纳其常见故障模式,并提出一套层次化、流程化的检修策略与工艺规范,以期为维修实践提供理论指导与技术参考。 展开更多
关键词 信号喇叭 控制原理 常见故障 检修策略
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基于矢量替换法的三电平变换器共模电压抑制研究
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作者 邹睿 陈昶 +2 位作者 马聪 曹志 姜雨枫 《电力电子技术》 2026年第3期71-79,共9页
在新型电力系统建设背景下,海量分布式能源随机接入对电力电子行业带来了巨大挑战与机遇。电力电子领域中T型三电平变换器已广泛运用在光伏并网系统、电机驱动系统等电气领域的各个方面。T型三电平逆变器在正常工作时会产生幅值与频率... 在新型电力系统建设背景下,海量分布式能源随机接入对电力电子行业带来了巨大挑战与机遇。电力电子领域中T型三电平变换器已广泛运用在光伏并网系统、电机驱动系统等电气领域的各个方面。T型三电平逆变器在正常工作时会产生幅值与频率较高的共模电压(CMV),影响设备以及电网安全稳定运行。国内外行业标准对电磁兼容性与电磁干扰提出了具体要求,降低CMV显得十分迫切。本文结合模型预测控制易于实现且具有设计灵活、动态响应快等特点,提出了一种基于离散矢量集模型预测控制(DSVM-MPC)的矢量替换策略,来抑制T型三电平变换器运用在电网系统中产生的CMV。该方法能够在不额外添加权重系数的前提下将CMV限制在±U_(dc)/6,且不会给中性点电位带来额外偏移,最后在T型三电平变换器仿真平台上对该方法的可行性和有效性进行了验证。 展开更多
关键词 三电平变换器 模型预测控制 共模电压抑制 矢量替换
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青海云杉常见病虫害诊断与防治
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作者 朱风玉 《园艺与种苗》 2026年第1期19-20,50,共3页
随着林木种植业的快速发展,青海云杉作为青海地区常见树种之一,具有适应性强、生长速度快等优势。该文结合青海云杉适合种植在潮湿、阴冷的河谷地带的生长特性,针对其各类病虫害的高发态势进行分析,提出有效的防治措施,为种植人员提供... 随着林木种植业的快速发展,青海云杉作为青海地区常见树种之一,具有适应性强、生长速度快等优势。该文结合青海云杉适合种植在潮湿、阴冷的河谷地带的生长特性,针对其各类病虫害的高发态势进行分析,提出有效的防治措施,为种植人员提供参考与借鉴。 展开更多
关键词 青海云杉 生长特性 常见病虫害 防治
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草鱼池塘养殖过程中常见病害防控实践总结
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作者 单中华 《河北渔业》 2026年第1期29-31,共3页
草鱼(Ctenopharyngodon idella)池塘养殖生产过程受养殖环境及苗种质量等多重因素影响,病害问题具有发生类型多样与诱发因素复杂等显著特点。为提升草鱼成活率和养殖效益,促进产业稳定发展,通过系统梳理草鱼池塘养殖过程中常见病害类型... 草鱼(Ctenopharyngodon idella)池塘养殖生产过程受养殖环境及苗种质量等多重因素影响,病害问题具有发生类型多样与诱发因素复杂等显著特点。为提升草鱼成活率和养殖效益,促进产业稳定发展,通过系统梳理草鱼池塘养殖过程中常见病害类型及其发生特点,围绕养殖环境调控、苗种管理等方面,提出了病害防控的关键技术措施,并通过分析生产实践案例,总结了草鱼池塘养殖防控技术体系应用的实践效果。 展开更多
关键词 草鱼(Ctenopharyngodon idella) 池塘养殖 常见病害 防控技术
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VB6中Common Dialog控件一次选择多个文件后的分离
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作者 毕传林 《九江职业技术学院学报》 2002年第1期36-38,共3页
本文介绍Common Dialog对话框选择多个文件,文件名的分离,Common Dialog新建,打开,保存文件的编程方法。
关键词 控件 公共对话框common DIALOG FILE Name属性 CurDir函数
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建筑工程施工的质量通病防治方案分析
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作者 回海龙 《中国厨卫》 2026年第2期244-246,共3页
近几年,随着我国城镇化建设步伐的逐渐加快,房屋建筑工程的数量也在逐年增加,同时产生了大量的质量问题。在实际建设过程中,施工单位需将质量控制工作放在首位,以保证工程质量。对此,文章针对建筑工程项目中常见的质量通病,提出针对性... 近几年,随着我国城镇化建设步伐的逐渐加快,房屋建筑工程的数量也在逐年增加,同时产生了大量的质量问题。在实际建设过程中,施工单位需将质量控制工作放在首位,以保证工程质量。对此,文章针对建筑工程项目中常见的质量通病,提出针对性的预防和控制施工质量对策。 展开更多
关键词 建筑工程 施工 质量通病 防治方案
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STRATEGY FOR DIESEL ROTARY ENGINE WITH COMMON RAIL INJECTION SYSTEM 被引量:2
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作者 WU Jinjun HAI Jingtao +3 位作者 SHI Jianzhong LI Xuesong YANG Qing WANG Shangyong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第3期412-416,共5页
A direct injection low compression ratios diesel rotary engine is designed and studied to find the appropriate application of the electronic controlled high pressure common rail injection system. Current development f... A direct injection low compression ratios diesel rotary engine is designed and studied to find the appropriate application of the electronic controlled high pressure common rail injection system. Current development focuses on the applied fuel injection and ignition strategies, especially concerning the combustion configurations of injectors, ignition source, and combustion chamber. The prototype engine, equipped with Bosch common rail system and high performance electronic control unit (ECU), is designed correspondingly. Studies show that the integration of a common rail injection system and the main and pilot duel injectors configurations, assisted with glow plug ignition device and flexible ECU, represents a promising approach to improve the potential of the low compression ratios diesel rotary engine. Currently the engine can run at 6 kr · min^-1 steadily and the power is about 68 kW/(4 kr ·min^- 1). 展开更多
关键词 Diesel rotary engine common rail injection system Electronic control unit(ECU)
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Control of switched systems with actuator saturation 被引量:5
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作者 Yang SONG Zhengrong XIANG Qingwei CHEN Weili HU 《控制理论与应用(英文版)》 EI 2006年第1期38-43,共6页
This paper is concerned with controller synthesis for linear switched systems with actuator saturation. Based on common Lyapunov function technique and multiple-Lyapunov function technique, two methods for designing s... This paper is concerned with controller synthesis for linear switched systems with actuator saturation. Based on common Lyapunov function technique and multiple-Lyapunov function technique, two methods for designing state feedback controller are proposed respectively in terms of linear matrix inequalities for the switched systems with saturation. An approach on enlarging the attractive domain is then investigated, The application of the presented approach is illustrated finally by a numerical example. 展开更多
关键词 Saturating control Switched systems common Lyapunov function Multiple Lyapunov functions
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Effect of common salt on laboratory reared immature stages of Aedes aegypti(L) 被引量:1
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作者 Mukhopadhyay AK Tamizharasu W +2 位作者 Satya Babu P Goutam Chandra Hati AK 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2010年第3期173-175,共3页
Objective:To observe the effect of common salt(NaCl) on immature stages of laboratory reared Aedes aegypti(L).Methods:A laboratory colony of Aedes aegypti mosquitoes of Rajahmundry strain was established in the labora... Objective:To observe the effect of common salt(NaCl) on immature stages of laboratory reared Aedes aegypti(L).Methods:A laboratory colony of Aedes aegypti mosquitoes of Rajahmundry strain was established in the laboratory of National Institute for Communicable Disease(NICD), Rajahmundry unit at(26±2)℃with relative humidity of(70±10)%.1.00%,1.25%and 1.50% solutions of common salt(NaCl) were selected to observe the susceptibility status of immature stages of Aedes aegypti in laboratory.Results:Fifty percent larvae of Aedes aegypti died within 19,31 and 48 hours when exposed to 1.50%,1.25%and 1.00%common salt solution, respectively.Ninety percent of the larvae died within 29,57 and 108 hours when exposed to the same salt solutions,respectively.Very high pupal mortality was observed varying from 81.8% to 40.0%.Formation of pupae was found inversely proportional in the presence of concentration of common salt in breeding water.Conclusions:With easy availability,less toxicity and long lasting nature,common salt may be applied in unused containers,especially in junkyards where surveillance mechanism is poor along with other conventional vector control methods in order to control breeding of Aedes aegypti,the vector of dengue/ dengue hemorrhagic fever and chikungunya. 展开更多
关键词 common SALT IMMATURE STAGES AEDES aegypti(L) control
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H-infinity control for cascade minimum-phase switched nonlinear systems
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作者 Shengzhi ZHAO Jun ZHAO 《控制理论与应用(英文版)》 EI 2005年第2期163-167,共5页
This paper is concerned with the H-infinity control problem for a class of cascade switched nonlinear systems. Each switched system in this class is composed of a zero-mput asymptotically stable nonlinear part, which ... This paper is concerned with the H-infinity control problem for a class of cascade switched nonlinear systems. Each switched system in this class is composed of a zero-mput asymptotically stable nonlinear part, which is also a switched system, and a linearizable part which is controllable. Conditions under which the H-infinity control problem is solvable under arbitrary switching law and under some designed switching law are derived respectively. The nonlinear state feedback and switching law are designed. We exploit the structural characteristics of the switched nonlinear systems to construct common Lyapunov functions for arbitrary switching and to find a single Lyapunov function for designed switching law. The proposed methods do not rely on the solutions of Hamilton-Jacobi inequalities. 展开更多
关键词 Switched nonlinear systems H-infinity control common Lyapunov functions Single Lyapunov functions
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The Efficacy and Safety of a Patent Pending Combination of Ginger and Goldenrod Extracts on the Management of Cold Symptoms: A Randomized, Double-Blind Controlled Trial
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作者 Johane Guay Pierre Champagne +1 位作者 Pascal Guibord Joerg Gruenwald 《Food and Nutrition Sciences》 2012年第12期1651-1657,共7页
Objective: In a randomized, double-blind, exploratory, active-controlled trial, the efficacy and safety of a patent-pending combination of Ginger and Goldenrod extracts (BDI-630) in alleviating cold symptoms in commun... Objective: In a randomized, double-blind, exploratory, active-controlled trial, the efficacy and safety of a patent-pending combination of Ginger and Goldenrod extracts (BDI-630) in alleviating cold symptoms in community-dwelling adults was compared to a combination of standardized amounts of Echinacea (EC) components. Methods: 44 healthy adults, experiencing new onset of cold symptoms were randomly assigned to receive either BDI-630 (900 mg) or EC (500 mg) twice daily for 10 days. The severity of cold symptoms and the quality of life was assessed by self-reporting of subjects using the Wisconsin Upper Respiratory Symptom Survey (WURSS-21? 2004). Results: The intent-to-treat population (ITT) consisted of 44 subjects (n = 22 for BDI-630;n = 22 for EC). The modified ITT (mITT) population consisted of 40 subjects, excluding four subjects with major protocol deviations related to inclusion/exclusion criteria and/or use of prohibited drugs from the efficacy analysis (n = 3 for BDI-630 and n = 1 for EC). Results indicated a sig-nificant difference between the two groups: the superiority of BDI-630 over EC was particularly noticeable between Day 1 and Day 7, as demonstrated by a 14-fold difference of the mean percentage of change of total score from baseline in the mITT population. Adverse events (AEs) following the intake of BDI-630 were mostly limited to mild gastrointestinal intolerance in less than 10% of the subjects. Conclusions: BDI-630 was shown to be more effective than EC in alleviating cold symptoms in the adult population, particularly during the first 7 days of treatment. BDI-630 was very well tolerated by all subjects. 展开更多
关键词 RANDOMIZED DOUBLE-BLIND Active-controlled Trial common COLD
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Model Reference Adaptive Control for Switched Systems with Closed-loop Reference Model Under Arbitrary Switching
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作者 Hao Yang Jing Xie Jun Zhao 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第3期35-42,共8页
This paper explores the model reference adaptive control problem for a class of switched linear systems under arbitrary switching with no need for the measurability of the system state.Based on the state of reference ... This paper explores the model reference adaptive control problem for a class of switched linear systems under arbitrary switching with no need for the measurability of the system state.Based on the state of reference model and the measurable output error, adaptive laws and controllers are designed for switched systems.Each subsystem may have its individual reference model and controller, which increases the design flexibility.The introduction of the closed-loop reference model is to get a better transient performance of the whole switched systems.A numerical example is provided to verify the effectiveness of the main results. 展开更多
关键词 SWITCHED systems MODEL REFERENCE adaptive control common LYAPUNOV function arbitrary switching the CLOSED-LOOP REFERENCE MODEL
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Design and Comparison of Controller for the Reduction of Conducted Electromagnetic Interference in an Inverter 被引量:1
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作者 P. Narasimman E. Latha Mercy 《Circuits and Systems》 2016年第7期1167-1176,共10页
This paper presents the design of a controller for the measurement and reduction of conducted Electro Magnetic Interference (EMI) caused in the power electronic circuits. The conducted EMI is also separating the Commo... This paper presents the design of a controller for the measurement and reduction of conducted Electro Magnetic Interference (EMI) caused in the power electronic circuits. The conducted EMI is also separating the Common Mode (CM) and Differential Mode (DM) simultaneously using Line Impedance Stabilization Network (LISN). EMI is mitigated by the fuzzy controller. By comparing common mode voltage with the standard reference value, the generated error can be minimized by using fuzzy controller. Fuzzy controller is varying the PWM signal of the power electronic switching devices for reducing the electromagnetic interference. In this paper, comparison of PI and fuzzy controller of the open loop and closed loop models are implemented using MATLAB<sup>&reg</sup></sup> SIMULINK for measurement and reduction of the EMI level;and also simulation results of the PI controller and fuzzy controller analysis are presented in this paper. The fuzzy controller is provided to achieve the EMI level of the inverter within the standard limit. 展开更多
关键词 Conducted EMI common Mode Differential Mode PI controller Fuzzy controller
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A Double-Blind, Randomized, Placebo-Controlled Nutritional Study Using an Insoluble Yeast Beta-Glucan to Improve the Immune Defense System 被引量:4
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作者 Hans-Joachim Graubaum Regina Busch +1 位作者 Heike Stier Joerg Gruenwald 《Food and Nutrition Sciences》 2012年第6期738-746,共9页
Purpose: In a placebo-controlled, double-blind, randomized clinical trial, the effect of an insoluble yeast beta-glucan preparation on the incidences of common colds and its effect on common cold symptoms were compare... Purpose: In a placebo-controlled, double-blind, randomized clinical trial, the effect of an insoluble yeast beta-glucan preparation on the incidences of common colds and its effect on common cold symptoms were compared to placebo. Methods: 100 healthy participants with recurring infections were randomly assigned to receive either placebo or yeast beta-glucan (Yestimun?;n = 50 each group) over a period of 26 weeks. The subjects had to document each common cold episode in a diary, and rate 6 predefined infections symptoms on a 3-point rating scale during an infection period, resulting in an infection score. The common cold episodes were confirmed by the investigators. Results: A total of 171 common cold episodes were documented. Of these, 76 were experienced by 38 subjects in the beta-glucan group and 96 were experienced by 48 subjects in the placebo group (p = 0.406). The beta-glucan group had significantly more subjects without incidences of common cold than the placebo group (15.6% vs 2.0%;p = 0.019). During the most intense infection season (first 13 weeks of the study), the beta-glucan group had significantly less infections compared to placebo (p = 0.02). Beta-glucan significantly reduced the typical cold symptoms (“sore throat and/or difficulty swallowing”, “hoarseness and/or cough” and “runny nose”) as opposed to placebo. Conclusion: The present study demonstrates a prophylactic effect of yeast beta-glucan on the occurrence of common colds as opposed to placebo. In addition, when these episodes occurred, they were from the beginning less pronounced and subsided faster. 展开更多
关键词 RANDOMIZED PLACEBO-controlLED Study INSOLUBLE YEAST BETA-GLUCAN common Cold IMMUNE System
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Secure and Performant Handling CIM-Based Data Streams in Control Room Software Interaction for Multi Vendor Solutions
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作者 Benjamin Requardt Sebastian Wende-von Berg Martin Braun 《Intelligent Information Management》 2020年第1期43-62,共20页
Due to the increasing share of renewable energy, new requirements are placed on control room software. Such software is often exclusive to the supplier, but other suppliers could offer new and better methods. For secu... Due to the increasing share of renewable energy, new requirements are placed on control room software. Such software is often exclusive to the supplier, but other suppliers could offer new and better methods. For security reasons, external applications often have no direct data access to control room software. Such software can provide information about the power grid via a periodic file transfer in CIM (Common Information Model) format. These files are often very large, containing complete records, delivering information not always relevant to the external applications. Extracting the relevant information required by external applications can be time-consuming, thus presenting a problem for time-critical applications. This paper presents a method allowing different applications to efficiently access the relevant data from the massive data stream contained in the CIM files. This method has been tested with a distribution system operator and clearly increases performance, allowing different applications to access the relevant data. 展开更多
关键词 common Information Model (CIM) GRID control ROOM SOFTWARE Electrical GRID
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