脈沖研變 的英文怎麼說
中文拼音 [màichōngyánbiàn]
脈沖研變
英文
pulse decary-
2. because lightwave systems commonly use fibers with randomly varying birefringence, it is important to study how optical pulses are affected by random birefringence changes
二、由於在一般光通信系統中,所採用的光纖的雙折射都是隨機變化的,因此研究光脈沖如何受光纖隨機雙折射變化的影響就變得十分重要。Our results show that with the up to date experimental data, 13c can not sufficiently burn, the neutron number density decrease, the timescale of neutron source become long and these come into conflict with model of thermal pulse agb star
研究結果表明,在新實驗結果下, 』 3c不能充分燃燒,中子數密度降低,中子源持續的時標變長,這與熱脈沖agb星的現有模型出現矛盾。A two - dimensional plain strain finite element model of infinite plate is developed to investigate the ultrasonic wave propagation and scattering on three kinds of cracks : parallel to the surface, 450 oblique angle to the surface, and quarter - circle
摘要建立了無限長板的具有吸收邊界的二維平面應變有限元模型,在研究了脈沖超聲波在無限長板中傳播的基礎上,對板中平行於表面的裂紋、與表面成45的斜裂紋和四分之一圓周弧形裂紋三種情況的脈沖超聲波散射進行了重點研究。( 4 ) finally, the ginzberg - landau equation is considered. by the ansatz method, the chirped femtosecond solitonlike solution is given, and the stability of the solutions are studied in detail by linear stability analysis with variation method. also the long - distance stability of the ultrashort pulse and the interaction between the solutions are also discussed by numerical method
( 4 )討論描述超短光脈沖傳輸的高階ginzberg - landau方程,給出該方程的啁啾類孤波解,並利用變分法解析地討論啁啾類孤波解的線性穩定性,同時研究這種類孤波解的長距離穩定性和相互作用。Based on the study of transferring characteristics of the lcc - type resonant voltage, the parameter combinations, which make widths and magnitudes of voltage pulses of resonant network adjustable, arededucedo when the following requirements are met : fn > 3, k > 3 or cp / cs > 8, the above circuit is of natural voltage - stabilized characteristics, thus open - loop control method for bucking voltage is presented and the experimental results verify that the method is feasible.,
實測整機在額定負載時效率達到88以上。在研究lcc諧振網路電壓傳輸特性的基礎上,推導出滿足可變寬度和幅度的諧振網路輸出電壓脈沖列的參數組合。設計f n 3 、 k 3或c _ p / c _ s 8時,諧振網路具有自然穩壓特性,因此本文提出並實驗驗證了一種整機為降電壓時的開環控制策略。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。Ultrashort pulse amplification, including chirped pulse amplification ( cpa ) and optical parametric chirped pulse amplification ( opcpa ), has been becoming one of the hot researches in the field of ultrashort pulse laser technology because ultrashort and ultrahigh intensity pulse laser has important applications in high field physics, such as x - ray laser, icf, laboratory astrophysics, laser particle accelerator, and so on
由於超短超強脈沖激光在x射線激光、慣性約束核聚變、實驗天體物理、激光粒子加速器等強場物理研究領域內的重要應用,超短脈沖激光放大技術目前已成為超短脈沖激光技術研究的熱點之一。它包括啁啾脈沖放大( cpa )和光參量啁啾脈沖放大( opcpa )兩大類。In this article, firstly the background of the textile trade conflicts within sino - us or sino - euro are introduced, thus learn that how to discern and dodge the foreign trade risks, how to choose the appropriate investment projects have already become one of the most important questions for exporting companies on foreign trade affairs well - known as high investment and high risk. so the main text makes a risk analysis qualitatively and quantitatively on a textile - exporting trading company from three angles of statistic 、 game theory and portfolio theory, which is the main content that we studied. firstly, the statistic article adopts data of the transaction closing price of the textile clothing index in shenzhen stock exchange at the end of each quarter as well as several other kinds of data reflecting the macro - economic changes, performs an empirical analysis of these data according to the theory of co - integration test 、 granger cause test and impulse response function of time series in economitric, and learn that the impact to ti is more obvious by the economic index reflecting local commodity price level and economic prosperity degree home and abroad, as well as the impact degree and the time lag degree, and knows the macro - economic risks faced by textile business enterprises ; after that by the game theory angle we analyze exactly the managing risks faced by one textile export corporation named beauty. from the game expansion chart the system arrangement between censor ways by exportation goal countries and exporting strategies by the exporting enterprises has been analyzed. involving the benefit assignment between them both the limited rounds and infinite rounds negotiations of cooperation games have been studied, and then country responsibility and the enterprise managing risks on foreign trade affairs and so on have been analyzed exactly ; in order to realize the investment multiplication in the certain degree to disperse the risk, the
本文首先介紹了中美、中歐紡織品貿易爭端的來龍去脈,由此可知在涉外貿易這種以高投入、高風險著稱的行業里,如何甄別和規避外貿風險、如何選擇合適的投資項目已經成為外貿企業的首要問題。因此,正文分別從統計學、博弈論和投資組合三種角度對涉外紡織品貿易公司風險進行了定性和定量的分析,這也是本文的主要研究內容。首先,統計學篇選取了深圳證券交易所行業分類指數?紡織服裝指數( ti )每一季度末的交易收盤價和若干種反映宏觀經濟變化的指標,利用計量經濟學中時間序列的協整檢驗、 granger因果檢驗和脈沖反應函數等理論做實證分析,從而得知反映國內物價水平和國內外經濟景氣程度的經濟指標對紡織板塊上市值的沖擊比較明顯,且可知沖擊程度和時滯度,進而分析出涉外紡織企業所面臨的宏觀經濟風險;接著,從博弈論的角度具體分析一家紡織品出口公司( beauty )的外貿活動所面臨的各種經營風險,該篇從博弈擴展圖入手,分析了出口目的國審查方式與本企業出口策略之間的制度安排;並圍繞雙方的利益分配,研究了有限回合和無限回合合作談判博弈,然後具體論述了國家責任和企業涉外經營風險等問題;在一定程度上為了實現投資多元化來分散風險的目的,投資組合篇從經典的markowitz模型著手,在一些特定條件的限制下,給出了一個相應的投資組合模型。We apply the agrawal ' s theory model of soa, and study the temporal characteristics of the output pulse for input picosecond optical pulses with different sharpness edges passing through a semiconductor optical amplifier, and find that the peak power and the pulse width of the output pulse depend on the input pulse peak power, the sharpness degree of the input pulse edge and the bias current of soa
本文應用agrawal的關于soa理論模型,詳細研究了具有不同陡峭邊沿的皮秒超高斯光脈沖經soa后的時域特性的變化,發現輸出脈沖的峰值功率、脈沖寬度與輸入脈沖的峰值功率、輸入脈沖邊沿的陡峭程度以及soa的偏置電流密切相關。( 2000 ). the neutron irradiation is assumed to derive primarily by the reaction 13c ( a, n ) i60 with a minor contribution from the marginal burning of 22ne through the channel 22ne ( a n ) 23mg in the final, high temprature phase of each flash. and we considered the influence of the various parameters such as the initial core mass, the envelope mass, the mass - loss rate, the overlap factor and the delution factor etc., and we vary their value with the pulse number
本文採用分叉s -過程反應通道,以~ ( 13 ) c ( , n ) ~ ( 16 ) o 、 ~ ( 22 ) ne ( , n ) ~ ( 25 ) mg為雙脈沖中子源,用最新的中子俘獲截面,利用gallino和busso等人給出的agb星三殼層核合成模型,考慮到核心質量、挖掘程度、重疊因子、稀釋因子及星風質量損失率隨脈沖數的變化,詳細計算和研究了各個金屬豐度情況下的3m 。Our results show that pmd induces pulse broadening randomly in high bit - rate optical fiber communications ; the synchronous amplitude modulation control may correct directly any position change of timing jitter and soliton interaction, so the transmission distance and pulse quality will increase further
研究結果表明對于高速率傳輸系統, pmd對脈沖的影響在時域上表現為脈沖形狀的展寬,這種展寬是隨機的;而同步幅度調制是在時域上,將發生形變的脈沖通過振幅調制,恢復原形,從而提高脈沖的傳輸性能。Shapes of pulse envelope are found to have some effect on the degree of phase influences. dependence of single - cycle pulse ( scp ) energy on the carrier phase has been studied for gaussian, lorentzian, hyperbolic secant and sine shapes respectively, which shows that these energies can be expressed in the same form. phase effect on pulse with gaussian envelope is the first to show, then are hyperbolic secant and lorentzian pulses, and sine the last
包絡對載波相位的作用范圍也是有一定影響的,我們對高斯、洛侖茲、雙曲正割和sinc四種不同包絡的脈沖,研究了單周期脈沖能量隨載波相位的變化規律,發現以上四種脈沖的歸一化能量均可在形式上用同一表達式表示,並發現對于這四種不同包絡的脈沖,高斯脈沖相位的作用最早體現出來,然後是雙曲正割和洛侖茲脈沖, sinc脈沖最遲。We have calculated and plotted the curves of the refractive index, group velocity index, lowest - order and second - order dispersion indexes as a function of wavelength. the lowest - order and higher - order dispersion - induced broadening and deforming of light pulses is analyzed for various pulse shapes, such as gaussian, super - gaussian and hyperbolic secant pulses
給出了折射率、群速指數、低階和二階色散系數隨波長變化的關系曲線,研究了高斯脈沖、超高斯脈沖和雙曲正割脈沖等超短脈沖在clbo晶體中傳播時,由於低階色散和高階色散引起的脈沖展寬和形變。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。It has important significance to study the welding technology of variable polarity pulsed mig for high efficiency weding and good quality of welding products. we should control the welding current, output voltage and the process of melting drop more effectively
研究薄板鋁合金變極性脈沖mig焊接技術,更有效地控制焊接電流、電壓輸出和熔滴過渡過程,提高焊接過程的穩定性、提高焊接速度,對于提高焊接效率和焊接產品質量具有重要的意義。On the aspect of experiment, the investigation has been carried out from simple to complicated, i. e. started from the single pulse and double pulses test of phase module, and then to consecutive - pulse chop test, and then to three phase inverting test
在試驗研究上,採用了由簡到繁,由易到難的策略,從相構件模塊的單、雙脈沖開關試驗入手,經過模塊的連續脈沖斬波試驗,再到三相逆變試驗。Linear frequency modulated ( lfm ) signals as the most popular pulse compression signal are a typical kind of time - varying, nonstationary signals, so applying the wigner - ville distribution into lfm signals has more advantages than conventional methods
雷達脈沖壓縮技術中所使用的線性調頻信號是一類典型的時變非平穩信號,採用時頻分析的研究方法處理線性調頻信號有著傳統方法無法比擬的優點。In this dissertation, radar detection in hrr has been taken as background. the followings are main contents of this dissertation : ( 1 ) based on analyzing the targets and the clutter ’ s specific characteristics of hrr radar, the echo models of targets and clutter have been studied respectively ; the changes of targets ’ echoes in different elevation angles, azimuth angles and attitude angles have been analyzed ; then, the echo models of lfm radar clutter have been established
本文針對高距離分辨雷達目標檢測開展研究,主要完成了以下幾方面的工作: ( 1 )分析了高距離分辨雷達目標和雜波回波特徵,在此基礎上分別研究了高距離分辨雷達目標和雜波的回波模型,分析了不同俯仰角、不同方位角以及不同姿態下目標回波模型的變化,並建立了線性調頻脈沖壓縮雷達的雜波模型。A prototype for 3000va 27vdc / 115v400hzac three - phase aviation static inverter with high frequency pulse dc link is designed and successfully developed
設計、研製成功了3kva27vdc 115v400hzac三相高頻脈沖直流環節航空靜止變流器。Development of plating power supply on adjustable - voltage and frequency with bipolarity pulse
雙端脈沖式變壓變頻電鍍電源研製分享友人