It is necessary to control the mechanical stimuli precisely in the studies of cardiac mechano - electrical feedback ( mef ). in the present study a ventricular pressure - clamping system has been developed, which can be applied to isolated - perfused rabbit hearts. controlled by a computer, this system not only can make the left ventricle follow a command defining the same pressure wave as that during a beating cycle under physiological condition, but also deliver mechanical stimuli with a proper waveform to the ventricle at a particular time phase. this system integrates multiple functions, including perfusing, pacing, recording of electrocardiogram and monophasic action potentials, and clamping and measuring of ventricular pressures in isolated - perfused hearts. thus, it is a distinct system for investigating the phenomena and mechanisms of cardiac mef at organ level
在心臟機械電反
饋的研究中準確控制機械刺激是非常重要的.本研究室構建了一套適用於離體家兔心臟的心室
壓力鉗系統.該系統通過計算機控制
壓力鉗,不僅能模擬正常生理條件下左心室的
壓力波形,還能在心室活動周期的特定時相、以適當波形對心室施加機械刺激.該系統集心臟灌流與起搏、表面心電圖記錄、單相動作電位記錄、心室
壓力鉗制與測定等多種功能於一體,特別適用於器官水平上觀察機械電反
饋現象並探討其機制
Abstract : it is necessary to control the mechanical stimuli precisely in the studies of cardiac mechano - electrical feedback ( mef ). in the present study a ventricular pressure - clamping system has been developed, which can be applied to isolated - perfused rabbit hearts. controlled by a computer, this system not only can make the left ventricle follow a command defining the same pressure wave as that during a beating cycle under physiological condition, but also deliver mechanical stimuli with a proper waveform to the ventricle at a particular time phase. this system integrates multiple functions, including perfusing, pacing, recording of electrocardiogram and monophasic action potentials, and clamping and measuring of ventricular pressures in isolated - perfused hearts. thus, it is a distinct system for investigating the phenomena and mechanisms of cardiac mef at organ level
文摘:在心臟機械電反
饋的研究中準確控制機械刺激是非常重要的.本研究室構建了一套適用於離體家兔心臟的心室
壓力鉗系統.該系統通過計算機控制
壓力鉗,不僅能模擬正常生理條件下左心室的
壓力波形,還能在心室活動周期的特定時相、以適當波形對心室施加機械刺激.該系統集心臟灌流與起搏、表面心電圖記錄、單相動作電位記錄、心室
壓力鉗制與測定等多種功能於一體,特別適用於器官水平上觀察機械電反
饋現象並探討其機制
From the simulation results, we can see that, for the presented cmos preamplifier - latch comparator, its transfer delay time is 231ps, and the power dissipation is 118. 6 w
時,其回
饋噪聲對輸入信號和電阻串參考電
壓產生的毛刺峰值分別是6 . 35mv , 1 . 57mv ;各級子adc的總功耗為5 . 57mw 。
The feedbacks of position, velocity, acceleration and dynamic pressure were applied to adjust the model, so the control system of single jar electrodraulic servo mechanism was built. to reduce the system error and interference error, the compound control was designed. the results of simulations showed that the magnitude attenuation and phase lag of the system come to the project demand
引入包括位置反
饋、速度反
饋、加速度反
饋和動
壓反
饋在內的反
饋控制技術對電液伺服驅動機構模型進行綜合校正,從而建立單缸電液伺服控制系統,並在分析系統誤差和擾動誤差后,加入復合控制減小系統誤差和抑制干擾,模擬結果表明復合控制系統的控製品質有了明顯改善,能夠滿足工程需求。
During the research of theory, developed models of power tetrode ( y841 ), and then examined the control characteristics using circuit analysis software, matlab - simulink. the analysis software tools was used to simulate the control system of high voltage power supply and yielded coincident results. by theory analysis, proved that control system design project of high voltage power supply was feasible, and provided direction for the system ' s experiment
運用matlab - simulink工具,對負高
壓電源的反
饋控制進行了模擬模擬,從模擬的結果來看,該控制系統能夠滿足負高
壓電源的- 80kv ,約100ms脈寬, 0 . 3精度的技術要求,而實驗結果也驗證了我們的設計是完全可行的。
We have designed the scanning and control system, which includes a pre - amplifier, a pid feedback and scanning - control circuit, high - voltage amplifiers and so on. the function of controlling scan and feedback has been realized
設計完成包含有前置放大電路、 pid反
饋和掃描控制電路、高
壓放大電路等掃描控制電路在內的掃描控制系統,完成各部分電路性能的測試及功能調試,實現反
饋和掃描控制。
It is suitable to be used as the medium to filter the high purity and strong corrosive gas or liquid, the air plug of battery, gasket, seals for medium / low pressure, the waveguide tube pre - heater for boiler, the sealing wash, the cover of big - powered micro - wave antenna, and radar antenna of twt etc
適用於過濾、高純度、強腐蝕性的氣體液體介質、蓄電池上作氣塞、襯墊、中低
壓密封元件、鍋爐波管預熱器、密封圈和軍用微波大功率天線罩,以及行
饋網路雷達天線等。
The voltage of bridge capacitor will become unbalanced, when inverter ' s input side is a single source. this phenomenon is inherent with the control of voltage feedback. a balance winding can overcome this shortcoming and widen the application of this circuit
採用單電源供電的半橋電路,如僅採用電
壓反
饋控制方案無法克服橋臂電容電
壓的不平衡,通過加入平衡繞組可以克服這一缺陷,擴大電路的應用場合。
The full - bridge converter was controlled with the pid strategy based on the feedback of voltage output
電源的全橋功率變換器採用基於電
壓瞬時值反
饋的數字pid控制。
First, it analyzes the working principle and some features of the system, such as the circulating current characteristics, power distribution characteristics, and characteristics about closed loop regulation of voltage. then it goes on to the study of some typical control methods, and designs on this basis, a parallel controller using a synchronization control strategy of racing to merging and a load - sharing strategy combined with feedback control and drooped control
文中,首先通過建立系統的數學模型,分析了逆變電源並聯運行的工作原理以及並聯系統的一些主要特性,包括它的環流特性、功率特性和電
壓閉環調節特性;在此基礎上,又研究了幾種典型的並聯運行控制方式;然後,採用搶占與並發相結合的同步控制方式和反
饋與下垂特性相結合的負載均分控制設計了並聯控制器。
Secondly, compared with some other kinds of comparator structure and based on the preamplifier - latch fast - compare theory, a novel topology of cmos preamplifier latch comparator circuit is presented. considering trade - off between kickback noise and power dissipation, reference resistance value is optimized. according to the encode demands of different stage resolution, clock - control encode circuit is designed
其後,在具體的子adc設計中,對比各比較器類型的優缺點,並基於預放大鎖存快速比較理論,提出一種新型高速低功耗預放大鎖存比較器電路拓撲;根據adc系統所允許的參考電
壓最大波動限制,在回
饋噪聲對輸入參考電平的影響和功耗之間折衷,確定優化的參考電阻串阻值;根據不同級精度的編碼要求,設計出時鐘控制編碼電路。
Current feedback vs. voltage feedback operational amplifiers
電
壓反
饋和電流反
饋運算放大器的比較
Rigid - flexible coupling system ; rotating flexible beam ; active vibration control ; positive position feedback ; piezoelectric ceramic
剛柔耦合系統旋轉柔性梁振動主動控制位置正反饋壓電陶瓷