結變容二極體 的英文怎麼說
中文拼音 [jiēbiànróngèrjítǐ]
結變容二極體
英文
junction varactor-
Based on consider hereinbefore, this dissertation discusses several aspects on the problem of the sustainable and optimum exploitation of groundwater resources as follows : ( 1 ) reviewed entirely the origin and evolvement of the concept " sustainable development ", stated and commented the study status in queue on " sustainable development " around national and international range, thorough discussed the science connotation about the concept " sustainable development " ; ( 2 ) looked back and commented across - the aboard some furthest basic concept and proposition related to groundwater resources, put forward self opinions on a few existent mistake points of view and chaos understandings ; ( 3 ) expatiated entirely on the content and meaning of the theory of changeable groundwater resources system, contrast with the traditional methods of groundwater resources calculation and evaluation, combined example to show the application of this theory ; ( 4 ) thorough analyzed the difficult and complexity to forecast the groundwater resources, fully stated the traditional methods of groundwater resources forecasting, pointed out the characteristic and applying condition of these forecasting method, introduced the main ideas and methods of wavelet analysis developed recently, and the matlab software be known as the fifths era computer language, and its accessory wavelet analysis toolbox, applied these methods and tools to analyze the groundwater dynamic curve, adopted the b - j method and morte - carlo method, combined with the theory of changeable groundwater resources system, discussed the new view on the forecast of groundwater resources ; ( 5 ) synthetically analyzed the characteristics and limitations of the present all kind of groundwater manage model, combined mathematical programming mathematical statistics random process and the theory of variation system of groundwater resources on the unite optimum attempter of surface water and groundwater, emphasized how to make the model more nicety, more simple, more practicality ; ( 6 ) analyzed the inside condition and outside condition to assure the sustainable and optimum exploi tation of groundwater resources, the inside conditions are the follows : correct resources idea, scientific methods of resources calculation and evaluation, credible forecast methods of resources, exercisable measures of resources management, the outside conditions are the follows : the development idea of high layer, the transform of manage system, the matched policy and rule of law, the adjusted of economy lever, the improve of cultural diathesis, the boosting up of water - saving consciousness and detail measures, the control of population rising, the prevention and cure of water pollute, the renew and rebuild of ecology ; ( 7 ) scan the sustainable and optimum exploitation of groundwater resources from the high level of metagalaxy, earth system science, and philosophy ; lint out the more directions on groundwater resources
基於以上考慮，論文主要從以下幾方面對地下水資源可持續開發問題進行了比較深入的探討：全面回顧了「可持續發展」概念的由來與演變，對國內外「可持續發展」的研究現狀進行了述評，並對「可持續發展」概念的科學內涵進行了深入探討；對涉及地下水資源的一些最基本的概念和命題進行了全面的回顧和評述，對目前仍然存在的一些錯誤觀點和混亂認識提出了自己的見解；全面闡述了地下水資源變值系統理論的內容和意義，並與傳統的地下水資源計算評價方法進行了對比分析，結合實例具體說明了方法的應用；深入分析了地下水資源預測預報工作的極端重要性和復雜性，對傳統的地下水資源動態預測方法進行了全面的評述，指出了各類預測預報方法的特點及適用條件，對最近二十多年剛發展起來的小波分析技術的主要思想和方法及其應用范圍，以及號稱第五代計算機語言的matlab軟體和附帶的小波分析工具箱進行了介紹，並應用於地下水動態過程線的分析，採用時間序列中的b ? j法，蒙特卡羅方法，與地下水資源變值系統理論相結合，探討了地下水動態資料分析和地下水資源預測預報的新思路；綜合分析了現今各類地下水管理模型的特點及缺陷，將數學規劃、數理統計、隨機過程等與地下水變值系統理論相結合進行地表水地下水或多水源的聯合優化調度，使模型更準確、更實用；對保證地下水資源可持續開發的內部條件和外部條件進行了分析，內部河海人學博卜學位論文前言、摘要、目錄條件主要是正確的資源觀，科學的資源計算與評價方法，可靠的資源預測預報技術，可操作的資源管理措施，外部條件主要是高層發展思路、管理體制的變革、配套的政策法規、經濟杠桿的調節、人文素質的提高、節水意識的增強及具體節水措施、人口增長的控制、水體污染的防治、生態的恢復和重建等;從宇宙科學、地球系統科學及哲學的高度審視地下水資源的可持續開發;指出了地下水資源可持續開發的進一步研究方向。Linear induction motor is an important kind of machines which have some merits such as simple structure, low cost, durability, convenience for maintenance etc. the subject of this thesis is to study a big circular ring linear induction motor, and the major works in this thesis are summarized as follows : ( 1 ) considering the effects of the finite length of primary core, one - dimension analytical solution for the air gap field is cited in this paper. based on it, the single layer winding magnetic field is studied. considering whole - pitched and short - pitched winding configuration with odd poles and half - fulled slots in both ends, the double - layer winding magnetic field is analyzed, respectively
本文對大圓環直線感應電機進行了深入細致研究，內容包括： （ 1 ）本文採用有限長行波面電流作用於有限長鐵芯上的模型，引用了氣隙磁場一維解，研究了單層繞組磁場，奇數極半填槽雙層繞組在採用整距和短距時磁場的分析、比較，簡單介紹了二維解； （ 2 ）用有限元軟體ansoft對大圓環直線感應電機空載氣隙磁場進行了靜態分析，並分析了結果； （ 3 ）用軟體進行了額定電壓下的瞬態分析，得到了轉矩，位移，轉速隨時間變化曲線圖，利用單極性霍爾元件測定轉速並與軟體計算結果進行了比較，採用等效電路法計算了堵轉時的最大電磁力並做實驗進行了驗證，由實驗測得了三相電流波形，並與計算結果進行了比較，對其不對稱性進行了定性分析。A lcc multi - resonant ( mr ) network is added to the traditional three - level converters to realize zvs. the unique arrangement of a multi - resonant network results in absorption of all major parasitic components hi the resonant circuit, such as transistor output capacitance, diode junction capacitance and transformer leakage inductance, which can eliminate parasitic oscillation in the converter
它的優點在於諧振電容吸收了開關管和續流二極體的結電容，諧振電感吸收了變壓器的漏感，使得開關管和續流二極體都能在軟開關的條件下完成導通和關斷過程，消除了電路中的寄生振蕩。In the light of present hotel e - commerce construction status and the macro - environment of china, chapter five proposes a stage - by - stage hotel e - commerce development strategy, after the comparison of the three entry approaches to the hotel e - commerce, it points out that hotels of china should make use of the good opportunity of the national golden tour project, join the tour hotel net positively and build up their own e - commerce. this will not only improve the inside flow and management of hotels, improve the service quality and working efficiency, but also can realize a global marketing and online reservation through the destination marketing system. it will enhance the whole competition level of the chinese hotel industry
第一章導論介紹了本文的研究意義、研究視角和方法；第二章介紹了本文所研究的飯店電子商務的概念與內涵，並對國內外飯店電子商務的發展現狀進行了對比，對制約我國飯店電子商務發展的原因進行了總結；第三章從經濟學的角度，對電子商務的應用價值進行了理論上的提煉；第四章開始將電子商務引入飯店，首先分析了電子商務在飯店企業中的適用性，然後介紹了飯店中電子商務的技術構建，再從管理學角度對飯店應用電子商務所帶來的商業模式變革及其價值進行了詳細闡述；第五章針對目前我國飯店電子商務的建設現狀和宏觀環境，提出了分階段發展飯內容提要店電子商務的戰略，並對三種飯店電子商務介入途徑進行了對比，指出應該借國家金旅工程建設的良好契機，積極加入旅遊飯店網，藉助現有的電子商務平臺，建設飯店電子商務，不但可以改善飯店企業內部流程與經營管理，提高服務質量與工作效率，還可以通過目的地營銷系統，實現全球營銷與在線預訂，增強中國飯店業的整體競爭水平。It also gives the motive of the ka - band vco and mixer, associated with the subject ' s requirement and the realistic conditions, according to which a proposal is confirmed that the gunn diode and the varactor are mounted in the same cavity to fulfill the vco and an antiparallel diode pair is used to fulfill the harmonic mixer. in chapter 2, based on the basic theory of negative resistance oscillating, we analyses the gunn oscillator and it ’ s tuning character. chapter 3 introduces the theory of millimeter - wave harmonic mixer
以此為根據結合課題需要和實驗室的實際條件，確定vco採用耿氏管腔體振蕩器形式，變容管與耿氏管安裝在同一個腔內以進一步減小體積，採用反向並聯二極體實現諧波混頻;第二章介紹負阻振蕩器理論及其調諧原理;第三章介紹毫米波諧波混頻器基本原理;第四章給出了振蕩器及諧波混頻器的設計過程，整個組件聯調的結果;最後是結束語，分析了電路中存在的問題，指出了改進方向。This essay mainly deals with how to help junior and senior school students overcome their difficulties in their mechanic learning, as they have many pre - science conceptions and mistaken cognitions. guided by the educational psychology, we may try testing the students such ideas by diagnosis. so we can know the basical contents of the students pre - science conceptions and mistaken cognitions by comparing and analysing the testing results of junior grade two and three, senior grade one and two. the sources and characteristics of such ideas are summ arized. some ways of how to correct the mistaken cognitions are also presented. at the same time, it points out that pre - science conceptions are the students " spiritual wealth, teachers must change senses about this, value the students " ideas and be instructions, helpers and promoters in correcting the students " such mistaken conceptions
本文主要是針對初、高中學生學習力學的過程中，存在許多的與科學概念相異的前科學概念和錯誤認識，給物理教學帶來了極大的困難。因此，試圖在教育心理學理論的指導下，對學生產生這些想法採用診斷法進行測試，並通過對初二、初三、高一、高二測試結果進行對比分析得出了初中生、高中生中所存在的前科學概念和錯誤的基本內容，總結了它們的來源和基本特徵，提出了糾正此類錯誤認識的措施和具體方法，同時指出前科學概念也是學生的精神財富，教師要改變觀念，尊重學生，做糾正學生前科學錯誤概念的指導者、幫助者、促進者。The goal of this subject is to sum up and exploit our technique how to produce low phase noise wideband vcos, through investigating and studying the basic theory and recent research fruits, combining national condition, and produce our low phase noise wideband vcos. using high q components, such as : coaxial resonator, dielectric resonator, makes bandwidth of vco become narrower, so that recently common wideband vcos generally make inductor and capacitor ( lc ) as resonators, combining varactors with wide range tunable capacitance, and achieve the wideband
本課題旨在通過對低相噪寬帶vco的基本原理、國內外在這方面的進展，結合國內的實際情況進行研究，總結和開發出自己的方法，形成自己的理論。並把它運用於實踐，以製造出低相噪的寬帶vco 。由於加入高q元件，如：同軸諧振器、介質諧振器等，會導致振蕩器帶寬比較窄，目前的寬帶vco一般採用電感電容（ lc ）作為諧振元件，輔之以大變容範圍的變容二極體，達到寬帶的目的。Compared with gunn diode, mesfet has the advantage of high efficiency, flexible design and easy to integrate. the two ports negative resistance oscillating network is analyzed and an extremum - line model of microwave transistor oscillating network output impedance is developed
Mesfet較之gunn二極體在vco電路中有效率高、設計靈活性、便於集成等優點，所以本文著重介紹了變容管調諧微帶結構mesfetvco的研製工作。分享友人