The following algorithms have been proposed and tested in the thesis : 1 frequency selective fading : combine the isomorphism between the input space and the output space and propose a new approach to blind equalization of the channel. compared with conventional methods, the new approach offers lower computational complexity, better performance, and more robust against the over - determination of the system order ; 2 time selective fading : a new approach to the equalization of time selective channel based on the zero - forced equalizer is proposed which is more simple in its structure of algorithm ; 3 time - varying channel : using the instantaneous mean value changes of the output signal to extract the information of channel variations and model it using ar model, kalman filter is then employed to track channel variations, it bears faster ability in tracking the variation of tv channels ; based on the isomorphism between the inputs and the outputs and some of the approaches using in mimo system, a new algorithm of equalization of simo time - varying channel is proposed, which also share the merits of being robust against the over - determination of the system order ; model the time - varying channel using the multi - resolution decomposition wavelets, and then a blind identification method based " on the model is proposed ; at last, a new model for equalization and identification of mimo system is proposed
主要工作在以下幾個方面: 1 、針對頻率選擇性衰落通
道:結合輸入輸出空間同構關系提出一種新的頻率選擇性通
道均衡方法,與傳統方法相比,該方法計算量更小,收斂速度更快,性能更優,且對系統階次的過確定表現穩健,具有實際均衡應用價值; 2 、針對時間選擇性衰落通
道:提出一種基於迫零均衡的時間選擇性通
道均衡方法,演算法結構簡單; 3 、針對時變色散通
道:
利用瞬態均值曲線提取通
道時變信息,對之ar建模,
利用卡爾曼濾波器跟蹤時變通
道抽頭變化,可以快速跟蹤通
道變化;基於輸入輸出空間之間的同構關系以及多輸入多輸出系統的處理方法,提出了新的單輸入多輸出色散時變通
道均衡與識別演算法,同樣具有對通
道階次過確定保持穩健的優點;結合小波多解析度分析提出一種基於小波模型的通
道盲識別演算法;研究時變的多輸入多輸出系統的盲均衡與盲反卷積問題,給出一種時變系統處理模型。
Feasibility analysis on usage of friction heat to transport crude oil in buried hot oil pipeline
埋地熱油管
道利用摩擦熱進行原油輸送的可行性分析
To travel by the usual route to moscow was not to be thought of, and the circuitous route which princess marya was obliged to take by lipetsk, ryazan, vladimir, and shuya was very long ; from lack of posting horses difficult ; and in the neighbourhood of ryazan, where they were told the french had begun to appear, positively dangerous
走往常經過莫斯科的那條路想都別想,因此瑪麗亞公爵小姐必須選擇的迂迴的路是:取
道利佩茨克,梁贊,弗拉基米爾和舒亞。這條路很長,因驛馬不是處處都有,所以又很艱難,同時,在梁贊附近聽說已出現法國軍隊,甚至還有危險。
In this thesis, the multi - channel sharing system is considered as a stochastic service system. based on the steady state solution of the birth and death process which state space is a limited set, utilized m / m / n / n / m queue model, the call congestion ratio formula and the channel utilization ratio formula fitting to the limited user system are derived. drawing support from the visual data analyzing function of the software matlab, the value divergence between the formulas and the corresponding one fitting to the infinite user system are compared
本文將多通
道共用通信系統視為一個隨機服務系統,根據有限狀態生滅過程的穩態解,
利用m m n n和m m n n m兩類排隊模型,分別推導出了無限用戶和有限用戶兩類多通
道共用系統的呼損率公式和通
道利用率公式;藉助于matlab的可視化數據分析功能,比較了這兩組公式在數值上的差異;指明了兩組公式的適用條件。
I am not sure about the exact mix of deposits, so i don ' t know what the interest spread is, but the spread between one - year deposits and one - year loans has narrowed by 9 basis points ( i think altogether it has narrowed by 27 basis points this year, but i have to check )
我並不很確定精確的混合存款額(是多少) ,所以我不知
道利率差額是多少;但是一年期存款與一年期貸款的差額已經縮短了9個基本點(我認為今年總共已經縮短了27個基本點,不過我需要核實) 。
A novel strip - coil - baffle structure used to enhance heat transfer and support the tube bundle for a tube - shell heat exchanger is proposed. the new structure can sleeve the tubes in bundle alternatively to create a vortex flow in a heat exchanger. the numerical simulation on the flow and heat transfer characteristics for this new structure heat exchanger is conducted. the computational domain consists of two strip - coil sleeved tubes and two bare tubes oppositely placed at each corner of a square. the velocity and temperature fields in such strip - coil - baffled channel are simulated using fluent software. the effects of the strip - coil - baffles on heat transfer enhancement and flow resistance in relation to the reynolds number are analyzed. the results show that this new structure bundle can enhance the heat transfer coefficient up to a range of 40 ? to 55 ? in comparison with a bare tube bundle ; meanwhile, higher flow resistance is also accompanied. it is believe that the strip - coil - baffled heat exchanger should have promising applications in many industry fields
介紹了一種用於強化管殼式換熱器殼側傳熱和支撐管束的螺旋折流片新型結構,該結構是對換熱器管子相間地套上螺旋折流片以產生旋渦流動.研究模型是在正方形布置的4個管子中的2個對角管子套上螺旋折流片后形成的通
道,
利用fluent軟體對該上述四管通
道模型的流場和溫度分佈情況進行了數值模擬;分析了四管通
道模型中螺旋折流片對強化傳熱和流動阻力隨雷諾數的變化關系的影響.算例結果顯示該新型結構可比相同尺寸的光管通
道中的情形傳熱系數提高約40 ? 55 ? ,同時也將伴隨較高的流動阻力.可以相信螺旋折流片式換熱器將會在許多工業領域有良好的應用前景
Abstract : a novel strip - coil - baffle structure used to enhance heat transfer and support the tube bundle for a tube - shell heat exchanger is proposed. the new structure can sleeve the tubes in bundle alternatively to create a vortex flow in a heat exchanger. the numerical simulation on the flow and heat transfer characteristics for this new structure heat exchanger is conducted. the computational domain consists of two strip - coil sleeved tubes and two bare tubes oppositely placed at each corner of a square. the velocity and temperature fields in such strip - coil - baffled channel are simulated using fluent software. the effects of the strip - coil - baffles on heat transfer enhancement and flow resistance in relation to the reynolds number are analyzed. the results show that this new structure bundle can enhance the heat transfer coefficient up to a range of 40 ? to 55 ? in comparison with a bare tube bundle ; meanwhile, higher flow resistance is also accompanied. it is believe that the strip - coil - baffled heat exchanger should have promising applications in many industry fields
文摘:介紹了一種用於強化管殼式換熱器殼側傳熱和支撐管束的螺旋折流片新型結構,該結構是對換熱器管子相間地套上螺旋折流片以產生旋渦流動.研究模型是在正方形布置的4個管子中的2個對角管子套上螺旋折流片后形成的通
道,
利用fluent軟體對該上述四管通
道模型的流場和溫度分佈情況進行了數值模擬;分析了四管通
道模型中螺旋折流片對強化傳熱和流動阻力隨雷諾數的變化關系的影響.算例結果顯示該新型結構可比相同尺寸的光管通
道中的情形傳熱系數提高約40 ? 55 ? ,同時也將伴隨較高的流動阻力.可以相信螺旋折流片式換熱器將會在許多工業領域有良好的應用前景
Then the temperature and spectral emissivity of material is calculated through processing the information data. this method has been quickly developed in the latest years because of the capability to get true temperature and emissivity without auxiliary instruments or other additional information
多波長輻射測溫法是在一個儀器中製成多個光譜通
道,
利用多個光譜的物體輻射亮度測量信息,經過數據處理得到物體的溫度和材料的光譜發射率。
There exits contradiction between the qos guarantee and complexity of channel assignment algorithms. and the channel search time is correlated with the channel utilizing efficiency. so each solution plan is the compromise among these factors
因為在系統的通信服務質量和通道分配演算法執行的復雜性之間存在矛盾,而且它與通道搜尋時間和通道利用率也有關系,所以任何一種解決方案的提出總是不同矛盾折中的結果。