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151.
Rosacea is a chronic cutaneous inflammatory disease that affects the facial skin. Clinically, rosacea can be categorized into papulopustular, erythematotelangiectatic, ocular, and phymatous rosacea. However, the phenotypic presentations of rosacea are more heterogeneous. Although the pathophysiology of rosacea remains to be elucidated, immunologic alterations and neurovascular dysregulation are thought to have important roles in initiating and strengthening the clinical manifestations of rosacea. In this article, we present the possible molecular mechanisms of rosacea based on recent laboratory and clinical studies. We describe the genetic predisposition for rosacea along with its associated diseases, triggering factors, and suggested management options in detail based on the underlying molecular biology. Understanding the molecular pathomechanisms of rosacea will likely aid toward better comprehending its complex pathogenesis.  相似文献   
152.
As technology feature size is reduced, ESD becomes the dominant failure mode due to lower gate oxide breakdown voltage. In this paper, the effectiveness of new gate and substrate triggering techniques has been investigated to lower the trigger voltage of the LVTSCR and MOSFET based ESD protection circuits using 2D simulations and HBM/TLP measurements. The simulation results show that the using these techniques reduces the ESD triggering voltage by 63 and 44% for MOSFET-based and LVTSCR-based ESD structures, respectively, under 2 kV HBM ESD stress. The effectiveness of proposed gate and substrate triggering techniques is also confirmed by the HBM and TLP measurements.  相似文献   
153.
张秀芹 《包钢科技》2001,27(2):32-34
本文论述了三相桥式整流装置采用集成运算式触发电路的结构和工作原理,并就其触发电路的特点与分立原件的触发电路和KC系列触发电路进行了比较,对在实际应用中易检修,维护的优点和可靠性进行了阐述。  相似文献   
154.
Skiers caught in a slab avalanche often trigger the avalanche themselves. Preventing those accidents necessitates a better understanding of the factors contributing to the failure of the snowpack under the action of a skier. In the present work, a mathematical model based on the principles of mixed-mode anticracking is proposed for skier triggering. The respective influences of the slope-normal and slope-parallel components of the load exerted by a skier on the prospective fracture plane are taken into account. A criterion for fracture propagation under typical skier loads is derived. It manifests a small number of factors that, combined, multiply the risk of triggering an avalanche. The criterion indicates, contrary to a common perception, that fracture is not more difficult to trigger in gentle slopes than in steep slopes. This major result of the model is confirmed by data obtained from field experiments.  相似文献   
155.
刘先任 《电讯技术》2002,42(2):76-79
提出一种基于过零触发机制的语音基频估计算法,该算法具有实时性好、易于硬件实现的特点。  相似文献   
156.
The characteristics of a low-voltage triggering silicon-controlled rectifier(LVTSCR) under a transmission line pulse(TLP) and the characteristics of high frequency are analyzed.The research results show that the anode series resistance has a significant effect on the key points of the snapback curve.The device characteristics can fit the requirements of a electrostatic discharge(ESD) design window by adjusting the anode series resistance. Furthermore,the set-up time of the ESD has an influence on the turn-on voltage of the LVTSCR.A steep rising edge will cause the turn-on voltage to increase.The parasitic capacitance of the device for different voltage biases and frequencies determines the capacitive impedance,and its accuracy calculation is very important to the ESD design of high frequency circuits.Our research results provide a theoretical basis for the design of an ultra-deep sub-micron(UDSM) LVTSCR structure under ESD stress and the improvement of TLP test technology.  相似文献   
157.
158.
为限制Nd:YAG激光器闪光灯抽运源在触发预燃时的功耗和电磁干扰,以符合国家关于医用电气设备对电磁兼容性的要求,研发了准谐振腔体触发预燃技术。由于脉冲变压器的寄生参量无法消除,会在电路中产生复杂的振荡过程。利用这一谐振特性,通过调节触发频率,使之与谐振频率相同,达到准谐振状态点燃闪光灯。实验证明该电路稳定可靠,其峰值电压可降到10kV以下,远低于同类闪光灯触发电压16kV的标称值。结果表明,该电路完全达到了国家关于医用电气设备对电磁兼容性的标准。  相似文献   
159.
To determine the potential signaling traffic reductions, the session establishment procedures were investigated. The investigation showed that the serving call session control function (S‐CSCF) is the major bottleneck in IP multimedia subsystem (IMS) network and the existing third‐generation partnership project (3GPP) service triggering algorithm (3GPP STA) based on initial filter criteria (iFC) increases largely the end‐to‐end session setup delay (SSD). To reduce the SSD and improve the system performance, a call‐state‐based application triggering architecture (CATA) was proposed. In CATA, the call‐state‐based filter criteria and the call‐state‐based service triggering algorithm (CSTA) were proposed, and then the modeling of 3GPP STA and CSTA was presented. Theoretical analysis and simulation results showed that the CSTA avoids the additional signaling traffic load of the S‐CSCF and application server effectively, which exists in 3GPP STA, reduces the SSD considerably, increases the throughput of the S‐CSCF and improves the quality of service of IMS network. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
160.
锂离子电池内短路是锂离子电池热失控事故中最常见的诱因之一,也是机械滥用、电滥用、热滥用的共性环节,是潜在的安全威胁。本文从锂离子电池内短路安全问题出发,综述了内短路机理的研究进展,归纳了内短路替代实验方法,介绍了内短路演化过程,指出了内短路检测需在其发展初期和中期完成。进而,总结了多种内短路检测方法,最后,对内短路问题下一步研究进行了展望。  相似文献   
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