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uploads/switch base.jpg

switch base 開關座〔一般為電木板〕。

switch box

As the kernel of internet , technology of routing is surely the emphasis of studies in network fields . there have been lots of material efforts researching in it . to improve the performance of routers on backbone networks , the scheme of high - speed network switching based on hardware has been developed . there are other great efforts focusing on extensive bgp routing measurement , from which a great deal of valuable data has been obtained , and many important phenomenons , such as delayed route convergence and as path inflation , are observed 另外有相當多的研究工作集中在路由測量上面。通過較大規模的測量,獲得了大量的有代表性的數據,從中觀察到很多路由現象,比如延遲收斂、 aspath膨脹等等。我們注意到在設計和實現新的路由協議之前,確定一個完善的特性集合具有十分重要的意義。

The system adopts cisco secure acs ( access control server ) 2 . 6 of cisco company as the authentication server , iplanet directory servers . 1 as the directory server and star - s1924f switch based on 802 . 1x as the authentication client namely user network access device to implement centralize management of the user account and password and so on in all the application , and the authorization access based on port 系統采用cisco公司的安全訪問控制器ciscosecureacs ( accesscontrolserver ) 2 . 6作為認證服務器, iplanetdirectoryserver5 . 1作為目錄服務器,以及實達的基于802 . 1x的交換機star - s1924f作為用戶接入設備即認證客戶端,實現用戶在所有應用的賬號與密碼等相對固定的信息集中管理和基于角色的訪問控制。

Abstract : by employing the concept of photon flux , the evolution of the phase and photon flux in the eigenmode state in three - wave mixing , and the requirements for the initial phase and photon flux in this state , are studied in the paper . a special state in which there are only exchanges of the photon flux but no phase variations in the three - wave mixing process is investigated . an all - optical switch based on the eigenmode pushpull nonlinear - optical - mirror is presented , and the properties of this all - optical switch are numerically calculated . the numerical results show that the performance stability is extremely good , and the intensity and phase of the output signal beams can be easily realized and controlled 文摘:利用光子流概念研究了三波混頻中本征模狀態的相位和光子流的變化,以及該狀態對光波的初始相位和初始光子流的要求,研究了三波混頻中只有光子流的交換卻沒有相位變化的特殊狀態,提出了本征模狀態推拉式非線性光環鏡的全光開關,并數值計算了這種全光開關的性能,數值結果表明,該光開關的性能穩定性好,并且易于實現和控制輸出信號光的光強及相位

A novel cycloconverter - rype three - phase hf link inverter topology for soft - switching based on phase - shifted full - bridge mode is proposed , whose main advantages are as follows : under the conditions of d < i < and overlap - d , the switches of the leading leg are turned on at zvs and the switches of the lagging leg are turned off at zcs and all switches of the cycloconverter circuit are commutated in the overlapping mode in the interval of zero voltage , which makes the circuit realize soft switching to the utmost extent and reliably solve the problem of peak voltage caused by the storing energy of leakage inductance of hf transformer 論文提出一種新型移相全橋軟開關周波變流型三相高頻鏈逆變器,電路的主要優點是:前級移相全橋的移相角控制在_ d _ i和_ ( overlap ) - _ d條件下,超前橋臂零電壓開通,滯后橋臂零電流關斷,并使周波變流器所有開關在零電壓期間重疊換相,使整機開關最大程度地實現了軟開關,并可靠解決了高頻變壓器漏感儲能引起的電壓尖峰問題。

Due to the complexity of the structure and control of cycloconverter - type three - phase hf link inverter for soft - switching based on phase - shift - controlled full - bridge mode , a simple and optimized vvvf control strategy is proposed . this control strategy includes : produced pwm by space voltage vector ( svm ) and equivalent carrier frequency fe = 1 / te are introduced into the pdm control of the cycloconverter ; softened equivalent pwm wave is generated at the notches of hf voltage pulses ; the harmonious control between regulating pulse width by phase - shifted angle and regulating voltage of equivalent pwm is to minimize the harmonics content of output voltage of the inverter 西安理工大學博士學位論文針對這種前級移相全橋軟開關周波變流型三相高頻鏈逆變器結構和控制的復雜性,提出了一種實現簡單而整體優化的vvvf控制策略:將空間電壓矢量產生p姍的方法svm和等效載波頻率fe = 1 / te引入到周波變流器的pdm控制;按高頻電壓脈沖前后沿軟化等效p翎波;用移相調節高頻脈沖寬度和等效p姍調壓協調控制逆變器輸出電壓,在滿足輸出電壓條件下使諧波最小。

The thesis also describes the design of the switch hardware , including microprocessor subsystem module , layer 2 / layer 3 switching module , fe interface module , ge interface module and out - band management module . the interface circuits among modules are introduced as well . finally , the thesis estimates the overall structure of the software . the implementation methods described in the thesis are also valuable references for the design of other switches based on other switching chips 接著文章詳細介紹了該款交換機的硬件設計,給出了包括微處理器子系統模塊、 l2 l3交換模塊、 fe接口模塊、千兆接口模塊以及帶外管理模塊在內的主要模塊的電路設計實現,對各模塊之間的接口電路也作了介紹,文章最后對軟件的總體結構進行了分析。

Chapter 2 in the design of sensors and switches based on photoinduced electron transfer , fluorescence was often used with high sensitivity and convenience . it is noteworthy that room temperature phosphorescence ( rtf ) has many advantages over fluorescence , e . g . , large stokes shift , higher signal to noise ratio , good selectivity and easily measurable luminescence lifetimes etc . , and it can be found as a helpful complementary method of fluorescence sensing 第二章在光誘導電子轉移傳感器和分子開關的設計中,熒光由于其靈敏度高、使用方便,受到人們的廣泛關注,相對于熒光室溫磷光選擇性好、信噪比高、較大的stokes位移、壽命易測定等優點,在許多方面與熒光互補。

Then it carefully analyzes and study catalyst 6506 router switching based on cos ( class of service ) ; the relationship between belief and disbelief and guaranteed system of the classification of statistics so as to decide some measures system of the classification of statistics so as to decide some measures to take accordingly . finally , it accomplishes the schedule of quality of service of the router . in this way , it will avoid the other influence of sub - privilege statistics , thus it provides wide band of privilege statistics all the way so as to make the privilege statistics go through the net swiftly 最后,成功地在路由交換機上實現了具有qos品質保證的流量控制策略,路由交換機可由權重式排隊算法來提供一定的服務品質給高優先權的數據流,使其通過交換機時能盡可能的避免其它低優先權數據流的影響,在路由交換機中全程提供高優先權數據流的帶寬保證,使得擁有高優先權的數據流能迅速地通過網絡節點。

Itu telecom world 2003 - geneva , switzerland - october 13 , 2003 - znyx networks , the leading provider of embedded high - availability ethernet for carrierclass systems , today introduced the zx5000 - the world s first commercially available gigabit ethernet switch based on advancedtca atca , a new industry standard architecture for telecommunications Znyx發布業界第一款atca以太網交換單板2003 - 11 - 20 ,嵌入式高可用以太網產品廠商znyx網絡公司今天宣布推出zx5000 -業界第一款商用的基于advancedtca ? atca規范的千兆以太網交換單板。

Considering the above control strategies which make the controller can not be real - time processing because its workload has increased , control circuits of the main switches based on eprom are designed , which can implement control scheme of firing angles and phase voltage . furthermore , it avoids power converter saturation in the process of commutation 上述控制策略的引入造成控制器運算量增大、難以在線實時控制,又設計了基于eprom的主開關器件通斷控制電路,實現了開關磁阻電動機開通關斷角控制及對施加于相繞組上電壓的優化控制,同時避免了換相時可能引起的功率變換器飽和現象。

In recent years , the developments of sensors based on photoinduced electron transfer for recognition of cations , anions , biological molecules in many fields and molecular switches based on photoinduced electron transfer as molecular devices for information technology in future were reviewed in details 綜述了近年來光誘導電子轉移傳感器在生命科學、環境科學、醫學、材料科學等領域內對陽離子、陰離子、生物小分子的識別及光誘導電子轉移分子開關在未來信息技術中用于集成化程度更高、體積更小的分子器件的研究進展。

Mems switches based on metal - metal contact are useful in a variety of power management information processing and communication systems because their on resistance is lower than that of semiconductor switches and their off resistance and transmission frequency are higher than that of semiconductor switches 在自動測試、控制系統、通信系統的信號通路等領域有著廣泛應用潛力,同時, mems開關是微機械技術中的一類有代表性的結構,是很多微機械器件的基礎。

By dividing the large array antenna into a set of virtual subarray antennas , the receivers are connected to each subarray via a program - controlled switch based on time - division - multiplexing , and process the output snapshots on the subarray - antenna 陣列天線劃分為虛擬子陣列,基于時分復用工作方式,通過程控交換矩陣與接收機連接,接收機對不同虛擬子陣列天線輸出信號分時進行接收處理。

Switching chip bcm5615 . the data flows in layer 2 and layer 3 are analyzed in detail . according to the analysis , the thesis describes the implementation of a gigabit routing switch based on bcm5615 之后文章對多層交換芯片bcm5615的交換結構、內部各個功能模塊的原理實現以及芯片中的二、三層數據流程作了比較詳細的分析。

Because of the special communication mode of the fcp , the work of analysis was done in chapter 2 . because the switches based on fcp is the kernel devices of san 由于支持fcp的交換機是存儲區域網的核心設備,但國內在這方面的成果還非常少,在市場上占主導地位的是國外公司。

Chapter 1 in this chapter , the principles of photoinduced electron transfer , sensors and molecular switches based on this principles were simply introduced 第一章簡要介紹了光誘導電子轉移基本原理,以及在此基礎上研究的傳感器和分子開關。

At present , the processor running the software in the circuit switch is highly integrated with circuit - switching based equipment 目前電路交換機中運行這一軟件的處理器是和采用電路交換方式的設備高度集成在一起的。

With the traditional switches based on circuit switching , voice signals are transmitted at the rate 64 kbits over networks 傳統的交換機是基于電路交換技術的,話音通信以64kbits的速率在網絡中傳輸。

For the first time , an integrated hall switch based on gaas mesfet process was fabricated 論文首次采用gaas直接離子注入mesfet集成電路工藝,研制出了gaas霍爾開關集成電路。