two-frequency system 中文意思是什麼
two-frequency system
解釋
二頻制-
This text summarises several control forms of gushing out oil pump test platform simply, and mainly proposes analog and digital control schemes of close ring adjusting speed, at the same time, gives the principles and implementation methods used in parameters control and measuring, this text introduces the asynchronous electromotor " s control process, in which, fuzzy control arithmetic is used, and the control commands are passed on by means of communication between mcu and frequency converter. there are two parts in this system. one is superior computer that is ordinary pc, the other is hypogynous at89c52. the functions of superior pc are control and display information through screen, and the functions of ats9c52 includes control, collecting, display, treatment, uploading of all parameters
詳細介紹了應用模糊控制演算法，以變頻器通訊方式進行異步電機調速的控制過程。系統由上位機和下位機兩部分組成。上位機為普通pc機，主要實現系統控制、數據顯示等功能，另外還有數據庫瀏覽、數據列印等功能；下位機以at89c52為核心，負責所有參數的採集、處理、顯示、上傳、控制等。 -
On the other side, we use the method of optical formation process to introduce two fundamental filtering function in frequency domain of coherence system of awg two optical processors are designed, that is optical signal add / minus and phase filter
另一方面，運用光學信息處理方法，我們探討了awg型相干系統頻譜區兩類基本的濾波函數的引入，設計了兩種光信號處理器：光信號加減器以及位相，濾波器。 -
Second, proposing a hybrid recommendation strategy which used multi - agent system, collaborative filtering, and top - n together to generate right recommendations for customers in different profitability tiers. in the first part, we have defined customer value from two categories : intrinsic value and network value. based on customer ' s historical behavior, segment them with considering their recency, frequency, and monetary
明確指出高價值客戶可體現在兩個方面：一是具有高自身價值的客戶，二是具有高網路價值（客戶的網路影響力）的客戶；其次，由顧客的歷史和當前行為，特別是從recency （最近訪問時間） 、 frequency （訪問頻度） 、 mon6t8ry （購買投人）因素出發，進行顧客內部價值挖掘：並通過形式化顧客的網路價值，給出完整的分層演算法和相應實驗。 -
Internal bio - field tumor thermotherapy system : internal bio - field thermotherapy, in abbrevitation, uses two high frequency sources with different frequencies and phases to cross act human body. it is kind of therapeutic method which could heat the whole or locals with physical energy, without damages of normal tissue, while directly inducing apoptpsis of tumoe cells
內生場熱療系統是採用兩組不同頻率相位的高頻源交叉作用於人體，利用物理能量加熱全身或局部，既不損傷正常組織，又使腫瘤細胞凋亡的一種治療方法。 -
Standard test method for impedance and absorption of acoustical materials using a tube, two microphones, and a digital frequency analysis system
管子雙擴音器和數字頻率分析系統用傳聲材料的阻抗和吸收的試驗方法 -
Company now have independence develop ten many china patent and many independence intellectual property ' s software copyright ' s product ; company major product : cable television consumer management control system ( but look for address 2 - 8 branches allot style, 8 - 32 gather line style ) ; shoot frequently plus unfasten harass system ( crowd plus crowd unfasten, cent two sections, point channel shan unfasten ) ; video frequency number subsections plus unfasten harass system ; cable television network burglarproof sow system ; number cable television product is with number mmds ( microwave ) systematically ; general purpose type prevent thunder supply electric appliances, shoot frequently automate supply electric appliances, but look for address control supply electric appliances ; power supply prevents thunder protection product ; pass flow branch, dispenser, split utensil, cavernous wave utensil, power supply inserts utensil, but transfer attenuator, but transfer equalizer wait for
目前擁有十多項中國專利和多個自主知識產權的軟體版權的產品；公司主要產品：有線電視用戶管理控制系統（可尋址2 - 8戶分支分配式、 8 - 32戶集線式） ；射頻加解擾系統（群加群解、分兩段、按頻道單解） ；視頻數字分段加解擾系統；有線電視網路防盜播系統；數字有線電視產品與數字mmds （微波）系統；通用型防雷供電器，射頻自動控制供電器，可尋址控制供電器；電源防雷保護產品；過流分支、分配器，分流器、陷波器、電源插入器，衰減器、均衡器等。 -
( c ) propose the scheme to implementing the coder and deoder of optical time - spreading / frequency - hopping, by assigning two orthogonal codes for one user and using these two codes to encoding 1 and 0 respectively, differential detection can be adopted. not only improves system performances in ber, but also resists the interference such as mai, and does n ' t need any control devices to evaluate the optimum decisive threshold
通過給每個用戶指定互相關為0的兩個地址碼分別發送1和0信號以及在接收端採用差分檢測技術，避免了ook （開關鍵控）光通信系統中0不發送光脈沖和ook常規檢測方式下最佳判決門限必須根椐用戶數等外界環境而改變，從而提高了系統性能和降低了系統的復雜度。 -
Medium plate plant of chongqing iron & steel has reconstructed technically the original two stand rolling mills ( roughing mill and finishing mill ) and changed dc drive system into ac frequency converter drive system
重慶鋼鐵集團公司中板廠對兩臺主軋機（粗軋機和精軋機）驅動系統進行了技術改造，將原來的直流驅動系統全部改造成變頻調速驅動系統。 -
In this system two oscillator are used for mixing. pll for high local oscillator and dds + pll for low local oscillator. by making full use of favourable narrow - band tracing filter character of pll and by combining the merits of dds such as super fine frequency resolution, high frequency accuracy, very fast frequency hoping with it, the pll / pll + dds frequency synthesizer presents wide band high quality source and super small frequency hoping step
系統採用兩次混頻，其中高本振的設計採用pll鎖相環頻率合成來實現，充分發揮了鎖相環頻率合成器的優良特性，實現了系統所要求的高質量寬頻帶本振源；低本振採用pll + dds頻率合成來實現，結合pll優良的鎖相特性與dds的高頻率解析度、高頻率精確度等優點，實現了頻率的小步進高精度合成。 -
Abstract : it provides a kind of new nonlinear integrator and its mathematical model. its frequency responses is disscussed by the harmonics linearization method. its phase lag is found to be only 27. 6, all high order harmonics are very small, and it is very resistant to disturbances. by using it, an two - objective optimum control system is designed. it has very good control performances and will have good prospects in application
文摘:提出一種新型的非線性積分器，給出它的數學模型，並用諧波線性化原理討論它的頻率特性，其幅頻特性起積分作用，而相位滯后僅27 . 6 ，高次諧波分量小，抗干擾能力強.應用這種積分器設計了一個雙目標優化的二次優化系統.模擬結果表明，系統的控制性能好，具有廣泛的應用前景 -
From the performance analysis of the inverter heat pump air conditioner, heat pump type vrf ( variable refrigerant flowrate ) air conditioning system, two - stage compression inverter air source heat pump, and cooling / heating / how - water inverter air source heat pump, the expanded function and performance improvement of air source heat pump from the variable frequency technology are analyzed in this paper
摘要以變頻熱泵空調器、熱泵型vrf空調系統以及我們提出的雙級壓縮變頻空氣源熱泵系統、供冷/供熱/供生活熱水變頻空氣源熱泵系統為研究對象，分析變頻技術引入空氣源熱泵系統帶來的功能拓展和性能提升。 -
In recent years, with the rapid development of the millimeter - wave radar technology and the demand of the safety, anticollision radar system is being studied and used widely. the if ( intermediate frequency ) circuit and the digital signal processing are two important parts of it
隨著毫米波雷達技術的日益成熟和人們對安全性的迫切需要，近年來，防撞雷達系統得到了深入研究和廣泛應用，如自動巡航控制、碰撞報警和防碰撞系統以及有待發展的雷達成像和汽車的自動駕駛系統等。 -
The study has completed the design of two - phase inverter and made up of the two - phase inverter - motor system for experimental use it is a variable frequency adjustable speed system with a open - loop control of rotational speed, which consists of voltage - controlled oscillator circulating assign device inverter circuit and two - phase induction motor a accurate mathematical model is set based on the whole system, and simulator program of dynamic and steady condition is established, which is used to calculate the dynamic and steady performance by kron and symmetrical coordinate converter by simulator calculation and experimental research with specific parameter of the system, a comparison is made between predicted and experimental characteristics, experimental measurements are shown to compare closely with corresponding theoretical result it is compared with some variable frequency adjus table speed system comprising inverter and single - phase induction motor from the system efficiency torque pulsation and the effect of two - phase inverter capacitance based on the conclusion, harmonic cancellation pulse width modulation control of a two - phase inverter - fed induction - motor drive system is researched, which cancelled the low harmonic and improve the system performance
通過對電機的kron變換和對稱分量變換，建立了系統較精確的數學模型，編制了系統動態及穩態運行的模擬計算程序分別計算系統的動態和穩態性能。通過對系統的具體參數進行了模擬運算和實驗研究，實驗和模擬結果進行比較，說明實驗和理論較為一致，並從系統效率、轉矩脈動及兩相逆變器電容的影響等方面與各種逆變器和單相異步電動機組成的變頻調速系統加以比較。在此基礎上，對兩相逆變器供電-異步電動機系統使用諧波抑制pwm控制進行了研究，由於減少了低次諧波，改善了系統性能。 -
Experiments show that, when use msp430f149 audio sensor to identify vehicles that contain plane, tank, truck and so on by time domain features and two - level f - ratio, the recognition rate is 82. 1 % ; when use both msp430f149 audio sensor and arm9 sensor to identify vehicles, and the recognition rate is much better than the original system and msp430f149 audio sensor. line spectrum of power spectra and 3 / 2 spectrum is used as frequency features on arm9 sensor, and it is caught by narrow - band bandpass filter
實驗證明，在主頻為8mhz的msp430f149感知器上，採用基於時域特徵和二階f比的識別演算法，能夠實時地完成對飛機、坦克、卡車等交通工具的識別;將msp430f149感知器與基於arm9的高端感知器配合使用，且高端感知器採用功率譜線譜或3 / 2維譜線譜作為頻域識別特徵，能夠實時的對各類交通工具做更高性能的識別。 -
Based on it, a new kind of helix slow - wave structure named elliptical helix slow - wave structure used in helix traveling wave tubes has been detailedly investigated. by studying the rf characteristics of this slow - wave structure, it ’ s found that higher operation frequency and interaction impedance will be obtained by increasing the eccentricity of helix or decreasing it of the shield. meanwhile, great potential of improving system bandwidth has also been found if the eccentricity of helix or shield or the two are properly choosed
本文對近幾十年大功率行波管的研究進展進行了簡單討論，並在此基礎上研究了一種可應用於螺旋線行波管的新型的螺旋線慢波結構，即橢圓螺旋線慢波結構，通過對該螺旋線高頻特性進行詳細分析，我們初步認為，選擇適當的螺旋線和屏蔽筒離心率，可以提高系統工作頻率，增加系統耦合阻抗，並且具有改善系統帶寬的潛力。 -
To meet the bandwidth requirements, a two - layer electromagnetically coupled rectangular microstrip antenna was introduced to the system. the influence of the inset position and the air thickness between the two layers on the impedance, resonant frequency, as well as the bandwidth was investigated
為使天線達到系統要求，本文設計了兩層電磁耦合矩形微帶天線，分析了影響天線性能的微帶饋線插入深度，微帶饋線與貼片間距以及空氣層厚度這三個參數。 -
In section one, we analyze the mechanism of lwi gain, and study the effects of the rabi frequency q of the driving field, the injection rates ratio rb / r ~, the exit rate r0, the decay rates ~ and rab between atomic levels, as well as 3 incoherent pump rate r on the gain without inversion, dispersion and population difference of the system. in section two, we discuss the effects of the detuning of the driving field and the probe field on the gain
在第一節中分析了無粒子數反轉激光增益產生的機制、研究了驅動場的rabi頻率、粒子注入速率比值r _ b / r _ c 、粒子退出速率r _ o 、能級間的自發衰減速率r _ （ c - b ） 、 r _ （ a - b ）和非相干泵浦速率r對增益、色散和粒子數差的影響；第二節討論了驅動場和探測場的失諧對無粒子數反轉激光增益的影響。 -
The dispersion - absorption relations of the two - level atom system tell us that at or near the resonance frequency, the index of refraction is large but absorption is equally large
由二能級系統的吸收色散關系得知，在共振或者近共振時，折射率很大吸收也很大。 -
After that, it discusses the principle of the band - pass technology, illuminating the feasibility of the digital intermediate frequency system based on the sampling speed which is two times lager than the signal band but unsatisfying the nyquist theorem
隨后討論了帶通采樣技術的原理，說明可以使用不滿足奈奎斯特低通采樣定理但大於信號帶寬兩倍的采樣速率進行中頻數字化，減輕基帶處理負擔。 -
With time - evolution - operator, it is proved that the population of upper level is in circumstance of cyclic oscillation by laser pulses pair of gaussian line - shape in a homogeneous broadening two - level system. the oscillatory time oxide is the delay time between the laser pulse pairs and the oscillatory frequency equals the one of transition between the lower and upper level
引入時間演化算符，證明均勻增寬二能級體系在飛秒激光脈沖對作用下上能級激發態布居是周期性變化的，它以飛秒脈沖對之間的延時為時間軸，以該原子能級之間的躍遷頻率為振蕩頻率
分享友人