脈動常數 的英文怎麼說
中文拼音 [màidòngchángshǔ]
脈動常數
英文
pulsation constant-
Results echocardiography displayed that inner - tunnel unobstructed, blood supply of coronary artery improved, eject fraction increased and thickness of endocardium returned to normal
結果患者術后多次行超聲心動圖檢查顯示內隧道通暢,冠狀動脈供血改善明顯,心臟射血分數增加,心內膜厚度恢復正常。Backed up by the soplat theory based on particle kinematics, the second chapter of this paper presents with analysis and simulation of several single observer passive measurement models, which uses such relative movement parameters as bearings changing rates and centrifugal acceleration information on the basis of bearings measurements. in the third chapter, the observability of location respectively using bearings and its changing rates information and centrifugal acceleration information is analyzed, and its observable condition is got. the fourth chapter puts forward the modified covariance extended kalman filtering ( mvekf ) against the defect of traditional extended kalman filtering ( ekf ), whose performance is simultaneously compared in the chapter with the performance of ususal tracking algorithm such as ekf, mgekf, iekf by computer simulation
在近年來提出的基於質點運動學原理的單站無源定位理論基礎上,本文第二章提出了幾種在角度測量的基礎上增加角度變化率及相對運動的離心加速度等運動學參數的單站無源測量模型,並對它們進行了分析和模擬;第三章分別對利用角度及其變化率信息定位和利用離心加速度信息定位的可觀測性進行分析並得到了相應的可觀測條件;第四章針對傳統擴展卡爾曼( ekf )方法的缺點,提出了一種修正協方差的擴展卡爾曼濾波( mvefk )方法,並將其和ekf 、 mgekf 、 iekf等常用的單站無源定位濾波方法進行了性能模擬比較;第五章通過引入雷達機動目標跟蹤方法和模型,提出了利用角度及其變化率對機動輻射源跟蹤的多級噪聲自適應方法和imm方法;第六章主要對角度變化率和離心加速度參數的獲取技術進行了研究,提出了幾種高精度測量脈沖序列多普勒頻率變化率的方法。The coupling from the pulse jet in the nozzle to the unsteady flow in the tube was discussed. and the relations between the parameters of gas charge and discharge, structure, working, flowing in tube and ideal cooling efficiency were established. the theory foundation of the influence of pulse jet on the flowing in the tube and characteristic would be built
探討了脈動射流與管內非定常流動的耦合問題,建立了脈動射流有關參數如進、排氣參數、結構參數、運行參數等和振蕩管內流動參數及理想製冷效率之間的普遍聯系,為研究脈動射流參數對振蕩管內流動及其性能的影響打下了理論基礎。This dissertation majorly researchs and designs full digital dc driving system with fuzzy control. it makes a scheme argumentation firstly, analyzing the pid algorithm and fuzzy control algorithm the ordinary digital pulse trigger algorithm and the double remainder method of pulse trigger in detail, and fuzzy control and the double remainder method are put forward to settle the under - mentioned problems, namely, the new viewpoint and the task having finished in this dissertation as follows : ( 1 ) in rder to overcome the influence of dc motor ' s parameter changing with time and nonlinear on the control system performance, this dissertation adopts fuzzy control as outside regulator and pi control as inside regulator in double regulators of the full digital dc motor driving system design ;. ( 2 ) aiming at the pulse trigger reliability of the ordinary d igital pulse trigger being low and leaking the pulse or the order of pulse confusion, this paper adopts the double remainder algorithm with short response time high pulse trigger reliability good adaptability and anti - jamming ; ( 3 ) this dissertation adopts tms320lf2407 which has good performance as major control chip this chip has power function with fast calculation capability, and accomplishes the software and hardware design in the dc motor driving system with fuzzy control ; ( 4 ) this dissertation also puts emphases on anti - jamming in hardware and software ; ( 5 ) after having designed the sample of full digital dc motor driving system with fuzzy control, a lot of experiments are performed to verify the performance and settles problems during experiment. the result of experiment proves the feasibility of design
首先進行了方案論證,對模糊控制演算法和數字pid調節演算法、觸發脈沖的一般演算法和雙余演算法進行了詳細地研究分析,提出應用模糊控制和雙余法解決下述問題,即該論文主要的新見解和所完成的工作: ( 1 )為了克服直流電機參數時變性和非線性因素對控制性能的影響,本設計中,雙閉環調速系統的外環採用模糊控制,內環採用pi控制,使系統在一定范圍內對直流電機參數變化和非線性因素影響有自適應能力; ( 2 )針對常規數字觸發器演算法中觸發脈沖的可靠性不高,經常出現漏脈沖或是脈沖混亂的情況,本文採用雙余法,該演算法具有響應快,可靠性高,具有良好的適應性及抗干擾能力; ( 3 )本設計中採用了速度快、功能強的tms320lf2407作為系統的主控晶元,應用該晶元完成系統的軟硬體設計: ( 4 )本文對系統抗干擾的軟硬體措施進行了重點研究; ( 5 )設計了具有模糊控制的全數字直流傳動系統原理樣機,並進行了試驗驗證,對試驗過程中出現的問題及時解決,最終實驗結果證明設計是可行的。In this thesis improved algorithms are presented as follows : ( 1 ) an algorithm based on the detection of arithmetical series is presented to deinterleave radar signals with stagger pris, especially to those with high order stagger ones. but this algorithm is limited to the model of stagger pri presented by resnick ; ( 2 ) an algorithm is presented to estimate the pris of radar signals with jittered pris based on stochastic dynamic - linear models. this algorithm fits radar signals with jittered pris well, especially when jittered amount is large
針對這種情況,本文提出了以下改進的重頻分選演算法: ( 1 )針對參差pri脈沖列提出一種重頻分選演算法,該演算法使用等差數列的檢測進行參差鑒別,非常適于對高參差雷達脈沖列的分選,但只局限於雷斯尼克提出的參差模型; ( 2 )針對抖動pri脈沖列提出基於動態線性模型的重頻分選演算法,非常適用於抖動量較大的情況。Methods cerebral blood flows were simulated on hemodynamics models of cerebral blood on condition of normal and stroke with practical measured normal carotid blood pressure pre - ecp and during ecp
方法將實際測量的正常的頸動脈血壓和進行體外反搏時的頸動脈血壓作用於正常情況下和缺血情況下腦血流動力學數學模型,模擬上述情況下腦動脈血流的變化。The components, working principle, advantages and defects of pwm power amplifier are introduced briefly in the dissertation. the working characteristics of h - bridge pwm power amplifier in double - polarity mode is analyzed qualitatively and qualitatively and the conclusion that fluctuant magnitude and continuousness of armature current are the essential parameters which can be used to evaluate pwm control modes
論文簡要介紹pwm功率放大器的組成、工作原理、特點及存在問題;對常見h型雙極性模式pwm功率放大器的工作特性作了定性和定量的分析,指出了電樞電流脈動量和電樞電流連續與否是衡量pwm控制方案優劣的兩個本質參數。Objective to observe the incidence of abnormal vascular structures in elderly patients with vertebrobasilar arterial insufficiency ( vbi ) using digital subtraction angiography ( dsa ) and to study the clinical value of dsa
摘要目的應用數字減影主動脈弓及全腦血管造影方法觀察老年椎基底動脈供血不足患者的血管結構異常表現,探討其在臨床上的應用價值。The paper researches the transient time precision and the following problem of the results developing with time for 2 - d high order blocking and matched method, at the same time, anlysing the stability of high order methods including boundary conditions. the results show that the domain decomposition and matched method using high order method can follow the time developing solution of taylor problem well, the computation result of the flow over a single or two tandem arranging circular cylinder agree the experiment and others " results well, moreover, the panting results of lift and drag coefficient are better than others
本文利用高精度分塊耦合求解方法,對其瞬態時間精度和非定常時間發展解的跟隨性問題進行了研究,同時也對包含邊界條件的線法高精度格式的穩定性也作了分析,研究結果表明高精度的分塊耦合求解方法可以很好地跟隨taylor問題的時間發展解,與單圓柱繞流和雙圓柱繞流的實驗結果比較以及他人結果比較符合很好,對升阻力系數在渦脫落時的脈動問題的結果優於他人結果。After the discussion of the numerical simulation method based on the fdtd method and the pml technique, the motions of the charges and the electrical field lines were first employed to describe the radiation procedures of the pulse electromagnetic waves. then the causes of how the charges are accelerated and how the motion status of the charges are maintained were further studied from the angle of interaction of charge and field. after these analyses, it was pointed out that the pulse radiation is due to the suddenly occurred time - varying electrical field ( displacement current ) in the open space. this view was further evidenced by two examples : one is the partly resistance loaded antenna, the other is the partly curved antenna. the radiation procedures of the pulse electromagnetic waves of many different situations were simulated throughout this paper with the contours and waveforms of electric field given. these figures are very helpful to the understanding of the radiation mechanism of the pulse electromagnetic waves
在討論了基於時域有限差分法和完全匹配層技術的數值模擬方法之後,首先從運動電荷和電力線的角度直觀地描述了脈沖電磁波的輻射過程,然後進一步從場與電荷相互作用的角度分析了天線上電荷是如何被加速以及如何維持其運動狀態的,指出了開放空間中突然出現的時變電場(位移電流)是脈沖電磁波輻射的根本原因.文中還對局部電阻加載的天線和局部彎曲的天線進行了研究,以進一步說明上述觀點.對多種情況下的脈沖輻射過程進行了數值模擬,並給出了電場的等高線和空間波形圖,這些圖形對理解脈沖電磁波的輻射機理非常有益In the process of building and using the mass concrete structures, because of the effect of out - side condition and themselves, some faults will form in the structure, these faults will effect the bearing capability and endurance using nondestructive testing method to test the concrete ' s quality and diagnose its healthy, which has the significant sense in assessing the safety stability and research of the administering diseases this dissertation mostly researched the testing methods in the mass concrete structure, discussed the principles, methods, features, sphere of application of the ultrasonic testing in the mass concrete structure with faults, used dynamic fem to simulate the testing process, discussed when the concrete structure with cracks is under the effect of the pulse, how the elastic waves propagate and what are their changing feature, researched the principles of the first - arriving waves " phase when the cracks " depths are not same, obtained the relation between the inversion point and the cracks " depth, which has the direction sense in the application of projects, the second part of this dissertation is ct, which used the ultrasonic wave running through the tested - substance to get arriving - time of the ultrasonic wave, then inverse the image this dissertation drawed one ct program which can well present the different little cells " ultrasonic wave velocity profiles of the substance, thereby to diagnose the quality of the part of the tested - substance, ct has the better using foreground.
在混凝土結構的施工及使用過程中,由於受其自身及外界各種因素的影響,常常會產生一些缺陷,對結構物的承載能力和耐久性造成嚴重影響,採用無損檢測技術進行質量檢測和健康診斷,這對混凝土結構開展安全、穩定性評估以及病害隱患治理研究具有重要意義。本論文主要針對大體積混凝土結構缺陷的檢測方法展開研究工作,重點討論了超聲波法檢測混凝土結構裂縫的基本原理和方法及其特點、適用范圍,運用動力有限元數值模擬其檢測過程,探討了有裂縫缺陷的混凝土結構在脈沖荷載作用下彈性波的傳播及其變化特徵,研究了不同裂縫深度下首波相位變化規律,得出了反轉臨界點與裂縫深度之間的關系,這對實際工程應用具有指導意義。聲波ct是一種新的無損檢測技術,它是利用聲波穿透被檢測體獲取聲波接收時間,來進行計算機反演成像的技術。Results the results showed the blood flow of the infertility patients were thinner than that of normal women, and ri was higher
結果不孕癥患者子宮卵巢動脈血流纖細、稀少,且動脈阻力指數明顯高於正常。Due to their large masses, their rotational periods are very regular. we can specify the periods of some pulsars up to more than ten decimal places. this allows us to study the small disturbances around the star
由於中子星非常沉重,所以它的自轉周期非常規律,有些中子星的脈沖周期可以準確至小數后十個位,因此,就算中子星出現輕微的異動,天文學家亦可以觀察得到。分享友人