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271.
民用飞机电子仪表仿真系统的设计与实现   总被引:2,自引:0,他引:2  
马锐  马存宝  宋东  张加圣 《计算机仿真》2006,23(12):62-64,95
在基于PC机的网络环境中,通过VAPS开发工具作为平台,利用C语言和网络通信技术,设计了一套民用飞机座舱主要电子显示仪表的仿真系统。基于模块化结构和事件触发驱动的设计思想,阐述了电子显示仪表仿真的功能单元及工作原理。讨论了系统实现中的仪表逻辑连接、坐标变换模型及数据通讯等若干关键技术。仿真结果表明,该系统逼真地演示出民机电子仪表工作过程,并且满足系统仿真的实时性要求,具有很强的工程实用性和通用性。  相似文献   
272.
在物理气相沉积过程中,触发真空间隙是整个试验过程中最基本的一步,很多因素影响真空间隙的成功触发,本文对此加以讨论,并提供一个合适的触发电路.  相似文献   
273.
    
Various types of cells demonstrate ubiquitous rhythmicity registered as simple and complex Ca2+-oscillations, spikes, waves, and triggering phenomena mediated by G-protein and tyrosine kinase coupled receptors. Phospholipase C/IP3-receptors (PLC/IP3R) and endothelial NO-synthase/Ryanodine receptors (NOS/RyR)–dependent Ca2+ signaling systems, organized as multivariate positive feedback generators (PLC-G and NOS-G), underlie this rhythmicity. Loss of rhythmicity at obesity may indicate deregulation of these signaling systems. To issue the impact of cell size, receptors’ interplay, and obesity on the regulation of PLC-G and NOS-G, we applied fluorescent microscopy, immunochemical staining, and inhibitory analysis using cultured adipocytes of epididumal white adipose tissue of mice. Acetylcholine, norepinephrine, atrial natriuretic peptide, bradykinin, cholecystokinin, angiotensin II, and insulin evoked complex [Ca2+]i responses in adipocytes, implicating NOS-G or PLC-G. At low sub-threshold concentrations, acetylcholine and norepinephrine or acetylcholine and peptide hormones (in paired combinations) recruited NOS-G, based on G proteins subunits interplay and signaling amplification. Rhythmicity was cell size- dependent and disappeared in hypertrophied cells filled with lipids. Contrary to control cells, adipocytes of obese hyperglycemic and hypertensive mice, growing on glucose, did not accumulate lipids and demonstrated hormonal resistance being non responsive to any hormone applied. Preincubation of preadipocytes with palmitoyl-L-carnitine (100 nM) provided accumulation of lipids, increased expression and clustering of IP3R and RyR proteins, and partially restored hormonal sensitivity and rhythmicity (5–15% vs. 30–80% in control cells), while adipocytes of diabetic mice were not responsive at all. Here, we presented a detailed kinetic model of NOS-G and discussed its control. Collectively, we may suggest that universal mechanisms underlie loss of rhythmicity, Ca2+-signaling systems deregulation, and development of general hormonal resistance to obesity.  相似文献   
274.
    
The triggering receptors expressed on myeloid cells (TREMs) are a family of activating immune receptors that regulate the inflammatory response. TREM-1, which is expressed on monocytes and/or macrophages and neutrophils, functions as an inflammation amplifier and plays a role in the pathogenesis of rheumatoid arthritis (RA). Unlike TREM-1, the role in RA of TREM-2, which is expressed on macrophages, immature monocyte-derived dendritic cells, osteoclasts, and microglia, remains unclear and controversial. TREM-2 ligands are still unknown, adding further uncertainty to our understanding of TREM-2 function. Previously, we demonstrated that TREM-1 blockade, using a ligand-independent TREM-1 inhibitory peptide sequence GF9 rationally designed by our signaling chain homooligomerization (SCHOOL) model of cell signaling, ameliorates collagen-induced arthritis (CIA) severity in mice. Here, we designed a TREM-2 inhibitory peptide sequence IA9 and tested it in the therapeutic CIA model, either as a free 9-mer peptide IA9, or as a part of a 31-mer peptide IA31 incorporated into lipopeptide complexes (IA31-LPC), for targeted delivery. We demonstrated that administration of IA9, but not a control peptide, after induction of arthritis diminished release of proinflammatory cytokines and dramatically suppressed joint inflammation and damage, suggesting that targeting TREM-2 may be a promising approach for the treatment of RA.  相似文献   
275.
为了解决配电网自动化系统中配电监控终端在线调试的问题,提出一套配电自动化工程仿真测试系统。系统通过仿真测试装置向现场的配电终端输出"三遥"信号,模拟配电线路的正常和故障状态,以检验现场工程中线路上各个配电终端的信息采集、传输、告警以及相互配合的故障隔离功能是否完备,同时检验配电网自动化设备的相关性能指标,具有较高的工程应用价值。  相似文献   
276.
故障电流限制器的晶闸管阀触发与监测系统   总被引:1,自引:0,他引:1  
在不改变电网结构的情况下,故障电流限制器作为一种全新的解决方案可用来解决由于负荷中心大电源投入和系统互联所引起的系统短路电流增加的问题。主要侧重于故障电流限制器的晶闸管阀触发与监测系统的研究。首先,介绍故障电流限制器的结构以及工作原理;然后介绍晶闸管阀触发与监测系统的构成,重点突出触发系统的原理、监测系统的原理和TE板的原理以及各自的实现方式,并提出了一种VBE与TE板之间的可实现逻辑时序;最后,通过低压试验验证了晶闸管触发与监测系统的可行性。  相似文献   
277.
Electrocardiogram (ECG) acquisition is still a challenge as gradient artefacts superimposed on the electrophysiological signal can only be partially removed. The signal shape of theses artefacts can be similar to the QRS-complex, causing possible misinterpretation during patient monitoring and false triggering/gating of the MRI. For their real-time suppression, an adaptive filter is proposed. The adaptive filter is based on the noise-canceller configuration with LMS coefficient updates. The references of the noise canceller are the three gradient signals that are acquired simultaneously with the noisy ECG. Tests were done on patients, on volunteers and using an MR-safe ECG simulator. The noise cancellers performance was measured offline, simulating real-time processing by point-by-point operations. To create worst-case scenarios, clinical sequences with strong- and fast-switching gradients have been chosen. The noise-cancelling filter reduces the gradient artefacts peak amplitudes by 80–99% after adaptation, without changing the desired ECG signal shape. The estimated reduction of total average power of the MR gradient artefacts is 62–98%. The proposed filter is capable of reducing artefacts due to strong- and fast-switching gradients in real-time applications and worst-case situations. The quality of the ECG is sufficiently high that a standard one-lead QRS-detector can be used for gating/triggering the MRI. For permanent patient monitoring, further improvements are needed.  相似文献   
278.
    
This paper investigates the problem of adaptive event‐triggering scheme for networked interconnected systems to relieve the burden of the network bandwidth. The data releasing is triggered by an adaptive event‐triggering device. The triggering condition depends on the state information at both the latest releasing instant and the current sampling instant. The threshold of the triggering parameter is achieved online rather than a predetermined constant. Taking the network‐induced delays and the coupling delays of the subsystems into account, together with the hybrid adaptive event‐triggering scheme and the stochastic uncertainty, we propose an unified model of the networked interconnected system. Sufficient conditions for the mean square stability and stabilization of the interconnected systems are developed by using Lyapunov–Krasovskii functional approach. A co‐designed method is put forward to obtain the controller gains and the weight of the triggering condition simultaneously. Finally, an example is provided to demonstrate the design method. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
279.
本文对电脑型可控硅焊机的软件触发技术进行了深入的研究。提出了利用 CTC 的一个通道进行重复定时的定时方式,这种定时方式具有硬件电路简单,动态响应灵敏度高的特点。采取软件触发后,使焊机的调试工作及触发电路大为简化。这种软件触发技术不仅可以应用在电脑型可控硅焊机上,也可以应用到其它微机控制的可控硅整流电路中。  相似文献   
280.
计算机技术在大功率整流装置中的应用   总被引:1,自引:0,他引:1  
对照原整流控制装置介绍了由株洲四方电力电子有限公司研制的、黑龙江齐化化工有限责任公司2001年10月新投运的RICS系列晶闸管整流装置计算机控制系统的应用。  相似文献   
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