Methods Sixty obese patients for laparoscopy were divided into three groups with 20 patients in each group, receiving volume controlled ventilation (VCV Group), or pressure controlled ventilation (PCV Group), or pressure controlled ventilation with positive end-expiratory pressure (PCV+PEEP Group).
方法选择60例行腹部腹腔镜手术的肥胖患者,按手术日期分为3组:容量控制通气(volume control ventilation,VCV)组,压力控制通气(pressure control ventilation,PCV)组,压力控制通气联合呼气末正压通气(pressure control ventilation and positive end expiratorypressure,PCV+PEEP)组,每组20例。
A on-identify model of proportional valve pressure controlled system was established though analyzing the configuration of DBETR type proportional pressure relief valve firstly,and then using classical step response method to identify system parameter,a practicable system simple model was deduced at last.
During steam drive, reservoir was pressure controlled at different stages to ensure the continuous expansion of steam drive zone under effective production pressure difference, which efficiently displaced interwell oil and improved the operation possibility of steam drive under present production techniques.
The mathematical model of oil feeding process of a wet clutch has been developed,with the pressure controlled by a pulse width modulation(PWM) digital proportional relief valve,and the model is simulated by MSC Easy5.Simulation results indicate that the relief valve can meet the demand of characteristics of the buffering pressure for gear shifting on vehicles,and the pressure in a shifting process is stable and controllable.
The new method firstly calculates bottom pressure through ground construction pressure,and then according to the coal bed's fracturing feature which is brief and wide,utilizing the ameliorate KGD model,combining with the derivation endure pressure controlled ingredient filtration model,ascertains the computing formula which gets along with crack propagation extension corresponding slit pressure.
④ The cognition of farmer on the physical harm of high-salt diet, smoking, and drinking, and the necessity of aerobic exercise and blood pressure controlled by drug increased as one's culture level (trend: χ2=43.02-2295.19, P < 0.01).
PUR film formation occurs in two stages, a solvent vapor pressure controlled stage, followed by a diffusion controlled stage.
Using a new, open-tube, horizontal slider-type liquid phase epitaxial (LPE) growth technique, in which mercury pressure controlled growth solutions are used, a high degree of growth solution compositional control has been demonstrated.
Slider LPE of Hg1-xCdxTe using mercury pressure controlled growth solutions
The applied pressure controlled the wear behaviour (rate) in a complex manner and its influence was dependent on material composition/microconstituents and test conditions.
The pressure controlled oxygen reordering processes in REBa2Cu3O6+x(RE=Y,Nd,La) causing the continous charge transfer between the CuOxand CuO2planes were investigated.
This paper, through construction dynamical analysis for the cylindrical container discusses the collapse mechanism of the hydraulic pressure controlled blasting, derives a new charge computational formula and gives the best depth under water in the hydraulic pressure controlled blasting.
Based upon the analysis of nine common used formulae for the quantity of charge in water pressure controlled blasting and the experience over ten times of practice, the author gives a new experimental formula. The calculating results and the effects of explosion show that they are in accord with each other.Five illustrations are given.
This paper presents a new method of steady flow to solve the problem that the injection rate into cores is difficult to get steady, especially for gas in measuring relative permeability. Here, the pressure-controlled capillary tube constant flow apparatus is used rather than micro-injection pump. This method has been proved to be practicable both theoretically and experimentally in this paper.