給定壓差 的英文怎麼說
中文拼音 [gěidìngyāchā]
給定壓差
英文
predetermined pressure differential-
Finally, we can not use electric power but the engine of bus or subsidiary engine to drive air compressors of bus air conditions. because the change range of turnaround speed of engine is very wide, that brings difficulties in controlling the rate of flow of cold - producing medium. in the control of bus air - conditions, preventing evaporator from freezing to make the air - conditions work with high efficiency and controlling the temperature of railway carriage are the basic tasks in air - condition control
與一般的建築空調相比，汽車空調的工作環境惡劣，條件差，控制難度要增加很多，主要體現在以下幾個方面：一是車外熱負荷變化大，難以確定控制參數；二是要求空調負荷大，而且要控制空調使其降溫迅速：三，不便於用電力作為動力源，必須用汽車發動機或輔助發動機來帶動壓縮機，當採用汽車發動機作為動力源時，由於汽車的車速變化大，發動機轉速的變化可從600r min到4000r min ，壓縮機轉速與發動機轉速成正比，其轉速變化高達7倍，給空調系統製冷劑流量控制帶來困難。Using the system designed in this thesis work, flow field calibration of the wind tunnel is accomplished, which covers dynamic pressure drop coefficient, dynamic pressure time stability, axial static pressure gradient, boundary layer, and degree of turbulence, etc. boundary layer measuring principle and method are especially described in detail, the relationship between boundary layer thickness, wind speed setting, and the depth of the experimental section is summarized, and finally the calibration data for th e model center zone under specific wind speed are given
然後利用本文設計的系統完成了落差系數、動壓時間穩定姓、軸向靜壓梯度、邊界層及湍流度等內容的流場校測。特別對邊界層測量的原理及方法做了較詳盡的敘述，總結出邊界層厚度與設定風速、實驗段深度的關系，然後給出模型中心區一定風速下校正數值。Comparing and analyzing the synchronous control strategy, which brings up the new method to control the double un - symmetry jars proceed synchronously with the combination of proportional valve and servo valve, which forms closed loop control ; basing on the above methods, models are made to get mathematics models of position control system and to analyze system model theoretically by using pid controller, we can realize regulating parameters, minimizing synchronous errors and enhancing the dynamic performances ; the simulink tool box in matlab software is used to imitate the system according to the model, which not only makes the result visual and easy to adjust the parameters in interactive way but also lets us understand the effects of different parameters and optimizes the dynamic properties. the theory of plc control in dshp is discussed after advanced understanding of the system movements. hardware design and general regulation are given on the base of siemens company products s7 - 200 plc
本文根據大量的國內外文獻，對研配液壓機的工作原理及設計結構進行了簡介；對位置同步的控制方法進行了比較分析，提出比例閥和伺服閥復合控制的閉環結構來對非對稱雙缸進行同步控制電液比例同步控制方案；在此基礎上著重對比例閥控非對稱缸建模，最後得到位置控制系統的總體數學模型，從理論上對同步系統動態特性進行了分析，並用pid控制器進行參數整定，減小雙缸同步誤差、提高系統的動態響應性能；其中控制性能的分析藉助于matlab軟體中的simulink工具箱，由已建立的數學模型形成模擬模型，得到可視化的模擬結果，從而利於交互方式下調整參數，了解不同的參數對系統的影響，優化同步系統的動態性能；在深入了解系統的動作特性后，對plc控制研配液壓機的原理進行了探討，針對siemens公司s7 ? 200型plc給出了硬體設計的總體規劃，編制出研配液壓機動作控製程序，在編程中著重研究位移傳感器與plc的通訊、雙缸同步運行的pid控制在plc上的實現及bcd碼撥盤輸入程序的植入問題。The fact that wave velocity in quasi - saturated soil is equal to that of fully saturated soil could not be calculated by effective fluid compressibility or explained by unwell - distributed saturation. we account for this in a new reasonable way which was based on kuster scattering effect analysis
（ 8 ）根據kuster散射波理論，計算了飽和度大於85的準飽和土體的彈性波速，其結果與試驗非常吻合；但是，通常所用的等效孔隙流體壓縮系數的方法所計算的結果與實驗結果差別很大，對此，筆者給予了一定的解釋。The paper makes use of multi - scale wavelet transform to detect the arriving time of the pressure wave to the both ends of the pipeline. the method could detect the break point of the signal, and could decrease the error bringing by the existing of impulse yawp
使用多尺度小波變換捕捉管道兩端負壓力波的到達時刻，有效地檢測出了信號的突變，並能夠較好地克服由於噪聲存在而給定位帶來的誤差。The flow equations are solved using finite difference technique. using body - fitted curvilinear coordinate system treated the boundary conditions. by iteratively solving the flow governing equation and the blade equation, the design of axial flow pump impeller in the quasi - three - dimensional rotational flow can be performed according to the angular momentum distribution, the blade which was designed in the lifting method, flow channel and the blade thickness given
其次在流動無粘性、不可壓及考慮葉片厚度的條件下，依據葉輪內的流動特性，推導了葉輪內三維流動周向平均流動控制方程以及葉片方程；在貼體坐標系中，採用有限差分法求解流動方程和葉片方程；在採用升力法設計出的葉片作為初始葉片、給定葉片速度矩分佈、葉片厚度分佈和葉輪軸面流道幾何形狀條件下，迭代求解流動控制方程及葉片方程，實現了軸流泵葉輪的準三維方法設計。To accept the current signal from high negative voltage circuit, the analog ground is raised to a certain positive voltage, which makes it possible for the signal amplitude to be compressed at the same time of its polarity reversion. a pi control program special for laser gyro current control is brought forward according to the conventional pid control method, in which the control signal is figured out corresponding to the difference between the sample and the reference value by turn of proportion - short step integral - long step integral. and at the end of this paper, a comparison of system performance on different conditions is made and the key elements influencing system performance are educed
利用集成a / d 、 d / a轉換器的新型晶元aduc824 ，實現了電流（電壓）采樣?數據處理?電流控制的閉環控制結構；地電位的抬升解決了a / d轉換器對負高壓迴路電流采樣時的輸入范圍匹配問題；控制信號反相的同時進行幅度壓縮，使得輸出調整電壓的解析度提高；根據常規的比例?積分?微分（ pid ）調節模型，針對陀螺系統的特性，給出了一種可以滿足系統要求、據采樣值偏差大小進行的比例?大步長積分?小步長積分、分層次比例?積分演算法；不同條件下系統穩流性能的對比、分析在論文最後給出，並據此找出了決定該系統穩流精度的關鍵因素，提出了系統的改進意見。The thesis has done the widespread investigation and study to the domestic and foreign ’ s technologies of analogy low voltage and low power, and analyzes the principles of work, merts and shortcomings of these technologies, based on the absorption of these technologies, it designs a 1. 5v low power rail - to - rail cmos operational amplifier. when designing input stage, in order to enable the input common mode voltage range to achieve rail - to - rail, it does not use the traditional differential input pair, but use the nmos tube and the pmos tube parallel supplementary differential input pair to the structure, and uses the proportional current mirror technology to realize the constant transconductance of input stage. in the middle gain stage design, the current mirror load does not use the traditional standard cascode structure, but uses the low voltage, wide - swing casecode structure which is suitable to work in low voltage. when designing output stage, in order to enhance the efficiency, it uses the push - pull common source stage amplifier as the output stage, the output voltage swing basically reached rail - to - rail. the thesis changes the design of the traditional normal source based on the operational amplifier, uses the differential amplifier with current mirror load to design a normal current source. the normal current source provides the stable bias current and the bias voltage to the operational amplifier, so the stability of operational amplifier is guaranteed. the thesis uses the miller compensate technology with a adjusting zero resistance to compensate the operational amplifier
本論文對國內外的模擬低電壓低功耗技術做了廣泛的調查研究，分析了這些技術的工作原理和優缺點，在吸收這些技術成果基礎上設計了一個1 . 5v低功耗軌至軌cmos運算放大器。在設計輸入級時，為了使輸入共模電壓范圍達到軌至軌，不是採用傳統的差動輸入結構，而是採用了nmos管和pmos管並聯的互補差動輸入對結構，並採用成比例的電流鏡技術實現了輸入級跨導的恆定;在中間增益級設計中，電流鏡負載並不是採用傳統的標準共源共柵結構，而是採用了適合在低壓工作的低壓寬擺幅共源共柵結構;在輸出級設計時，為了提高效率，採用了推挽共源級放大器作為輸出級，輸出電壓擺幅基本上達到了軌至軌;本論文改變傳統基準源基於運放的設計，採用了帶電流鏡負載的差分放大器設計了一個基準電流源，給運放提供穩定的偏置電流和偏置電壓，保證了運放的穩定性;並採用了帶調零電阻的密勒補償技術對運放進行頻率補償。At the end of the experiment, we reconstructed the subsystem of second air measuring, i. e. we used airfoil measuring equipment as a replacement of original equipment of flute pipe. we also demarcated the velocities of spouts of burner which can deal with correlative data, and which can provide some help for operation
最後又對監測系統二次風測量子系統進行改造，將原笛型管裝置修復為機翼測風裝置，對傳感器進行差壓標定;在爐內噴口處標定速度，將數據進行處理，提供給熱工控制顯示用，對運行調整提供了幫助。Firstly, the performance is calculated at the design point of the ws - 9 aeroengine by using the numerical model established. secondly, after obtaining the performance coupling parameters, the steady - state performance of the non - designed points is caculated. third, respectively make the limitation of rotate speed of the high pressure rotor and low pressure rotor equal to corresponding parameters of designed point, after the data calculated compared with those of designed point and actual testing of the manufactory, the error is obtained
首先，用所建立的發動機數學模型計算了發動機在設計點的各項性能，第二，根據發動機各部件的耦合特性參數計算得到發動機在非設計點狀態下的各項穩態性能，第三，分別設定限制高壓轉子轉速和低壓轉子轉速逼近設計點條件下對應的參數，將計算得到的性能數據與設計點性能進行了比較，並將非設計點的計算結果與生產試車過程實測的性能數據進行對比，給出了該穩態模型計算結果與實際試車數據的誤差。Differential pressure measuring instruments with electric contacts are suitable for controlling and regulating process sequences by means of the given process pressure
有電接點的差動式壓力測量儀表適用於根據給定生產壓力，控制和調節工藝步驟。Differential pressure measuring instruments with electric microswitches are suitable for controlling and regulating process sequences by means of the given process pressure
有電子微開關的差動式壓力測量儀表適用於根據給定生產壓力，控制和調節工藝步驟。Secondly, among the single mothers, those who have the experience of divorce tend to hold that their own efforts are not useful for the improvement of marriage relations, and to believe that if crises occur in their marriages, divorce is the inescapable fate and it is the spouses " behavior that leads to the failure of marriage. thirdly, those who have lost their husbands will more idealize their marriages, and blame much more of themselves when there are some crises in their marriages. fourthly, the factors such as personality, age, years of education, years of being single will influence the perception of the underlying causes of satisfaction or dissatisfaction in marriage, and meanwhile the attribution in marriage is correlated with the swb ( subjective well - being ) and satisfaction of life
根據調查的結果，我們發現： （ 1 ）單身母親生活負擔沉重、健康狀況不佳、心理壓力大、對生活質量評價低、主觀幸福感差，是弱勢群體中的弱者； （ 2 ）單身母親群體中，有過離異經歷的婦女更傾向于認為自身的努力無助於改善婚姻關系，如果婚姻出現危機，破裂將是難以避免的，並將失敗的責任更多地推卸給外部因素； （ 3 ）喪偶組婦女在分析婚姻成敗的原因時，表現出將婚姻生活理想化的傾向，並且在婚姻出現危機時，比其他婦女更傾向于將責任歸咎為自己，而產生更多的自責情緒； （ 4 ）性格特徵、年齡、受教育程度、單身時間的長短等因素都會影響個人對婚姻成敗原因的判斷，同時，對婚姻成敗的歸因與主觀幸福感、生活滿意度都有一定的相關。Direct torque control using space vector modulation ( svm - dtc ) scheme is discussed and the detailed designed, including space vector choosing and modulating, to overcome the control difficulties coming with the characteristic of low inductance. comparing with the basic dtc, the simulation results confirm the feasibility and good performance of this strategy. in order to reduce the torque error in dynamic state resulted from the nonlinear relationship between the torque and torque angle, a proportional - plus - integral ( pi ) torque controller with variable proportion is presented to ensure exact and quick control of torque in dynamic state
系統的闡述了永磁同步電機直接轉矩控制理論，分析了改進后的svm - dtc控制策略，並具體設計了控制技術的實現方案，包括參考矢量的生成和空間電壓矢量調制的方法；為減小電磁轉矩與轉矩角非線性關系這一因數給電機電磁轉矩動態調節造成的誤差，本文實現了變比例系數轉矩pi調節器的方案，確保了系統穩定性的同時，實現了電磁轉矩在動態過程中快速而準確調節。Based on the previous and through the uniaxial tension damage experiment and comparing to the uniaxial compression damage experiment, the paper makes research on the anisotropism of the damage and the difference of the damage between the uniaxial tension and the uniaxial compression, combining with orthogonal anistropic damage model and exponent function damage developing equation. through the formulae deduction, the damages caused by the same absolute value tension and compression strain have the comparing character in some extent and corresponding decay coefficient
本文在前人研究的基礎上，通過單軸拉伸損傷試驗，及其與單軸壓縮損傷試驗的比較，進一步結合正交異性損傷模型與指數函數損傷演變方程，對混凝土體中損傷的各向異性以及單軸拉伸和單軸壓縮情況下損傷的差異性進行了研究探討，經過公式推導，提出絕對值相等的拉、壓應變產生的損傷具有一定的可比性，並給出了進行可比性換算的折減系數。If applied experiential formula mechanically to calculate the dynamic moment of the tri - eccentric butterfly vavle, its errors for the results would be larger. the paper, by virtue of the postulate of flow with fixed constant, eddiless of ideal liquid, calculated laplace equation by finite difference method in rectangular coordinates, gained pressure distribution on the butterfly disc section, thereby figured out its dynamic moment under each opening angle and the method was feasible for calculating dynamic moment of symmetry or not, designed the program and described the curve of dynamic moment. finally, the paper infered their laws
採用經驗公式來計算三偏心蝶閥的動水力矩，誤差比較大，本文根據三偏心蝶閥的結構特點，利用理想流體的定常、無旋流動的假定，用有限差分法在直角坐標系中求解拉普拉斯方程，得到蝶板截面上的壓力分佈，從而計算出蝶板在各個開度下的動水力矩，設計出了求解的程序，給出了程序運行的結果並進行了數據處理從而得到了動水力矩曲線，總結了它的變化規律。For the model with defined pressure on boundary both inside and outside, the thesis first proofed the discrete numeric solution existence of the general difference equation to the seepage mathematical model by discrete functional analysis ; then it presented a concise and effective numeric solution, predicted - corrected method, and proofed the convergence of it
（ 3 ）對于內邊界為定壓生產、外邊界也為定壓生產條件下的滲流數學模型，首先利用離散泛函分析方法，就該模型一般形式的差分方程證明其解的存在性;然後給出一種針對此問題的具有較高效率的預估?校正方法，並證明其收斂性。Mechanical differential pressure switches are suitable for all areas, where an electrical signal is related to a given differential pressure value
當電信號與給定差壓值有關時，就該使用機械式差壓開關。In recent times, however, the increasing trade surplus, together with the rising foreign exchange reserves, have caused sever pressure on the appreciation of rmb. under such circumstance, on october 2003, the state taxation administration has announced “ notice of the ministry of finance and the state administration of taxation on adjusting the export rebate ”, expecting that this new regulation would improve the structure of exporting commodities, and lessen the pressure of rmb appreciation
但是，近年來我國出口貿易順差連年增長，外匯儲備不斷增加給人民幣升值造成了一定的壓力，在這種情況下，國家稅務總局於2003年10月份出臺了《關于調整出口貨物退稅率的通知》 ，目的在於改善我國出口產品結構，緩解人民幣升值壓力等分享友人