By contracting several databases , sql server 2000 is selected for the property database platform . then the structure and function of sql server 2000 are anatomized in the thesis . finally the structure of the route codes and the meaning of each data code are analyzed 通過(guò)對(duì)幾種數(shù)據(jù)庫(kù)的對(duì)比分析,從中確立了sqlserver2000作為本系統(tǒng)的屬性數(shù)據(jù)庫(kù)平臺(tái),然后對(duì)sqlserver2000結(jié)構(gòu)及功能進(jìn)行了詳細(xì)的剖析,并完整分析了路線(xiàn)代碼的結(jié)構(gòu)及各個(gè)數(shù)據(jù)代碼代表的意義。
When the gsm based gate - way is designed and realized , the paper emphasizes the short message communication technique used in transmitting location data , involves short message actualization unit , protocol configuration , receiving / transmitting process , data pdu encapsulation , data coding , and so on 在系統(tǒng)gsm通信網(wǎng)關(guān)的設(shè)計(jì)與實(shí)現(xiàn)中,重點(diǎn)對(duì)系統(tǒng)中采用的短消息數(shù)據(jù)傳輸技術(shù)做了詳細(xì)的分析,包括短消息的實(shí)施單元、協(xié)議結(jié)構(gòu)、收發(fā)過(guò)程以及信息傳輸過(guò)程中數(shù)據(jù)的pdu封裝等。
The signal processing can ensure and improve the performance of plc , the main methods include filter , data coding , error correction , etc . firstly , the characteristic of power line channel is discussed from the transmission lines , noise , and channel attenuation in this paper 信號(hào)處理研究是為了保證電力線(xiàn)通信質(zhì)量、提高其性能,主要的方法如數(shù)據(jù)編/解碼、糾錯(cuò)、抗干擾處理等。本文首先從傳輸線(xiàn)特性、信道噪聲和信道衰減三方面分析了室內(nèi)電力線(xiàn)信道的特點(diǎn),并提出一種適合室內(nèi)近距離的電力線(xiàn)載波通信方案。
In this thesis , principles of data coding for transferring data among different network hierarchies is described , a channel and program management center and a user authorization center are designed , and the integration and application of the system into sdh / hfc network are investigated and implemented 本文對(duì)系統(tǒng)中支持不同網(wǎng)絡(luò)體系間數(shù)據(jù)格式的轉(zhuǎn)換的數(shù)據(jù)編碼原理進(jìn)行了描述。設(shè)計(jì)了該系統(tǒng)頻道和節(jié)目管理中心以及用戶(hù)授權(quán)管理中心的構(gòu)架,并對(duì)高速數(shù)據(jù)廣播系統(tǒng)在sdh hfc網(wǎng)絡(luò)中的集成和應(yīng)用進(jìn)行了較為深入的研究。
At first , this article introduces the dicom information model and dicom network protocol architecture ; specify the definition of dicom service and object , message data coding , encapsulation of protocol data unite ( pdu ) and the mechanism of message exchange , etc . and then synoptically specifies protocol data unite , presentation data value ( pdv ) , encapsulation of various compose items and the class clusters for this program 本文首先介紹了dicom標(biāo)準(zhǔn)信息模型及其網(wǎng)絡(luò)協(xié)議構(gòu)架,并且深入淺出地介紹dicom的服務(wù)和對(duì)象定義、消息數(shù)據(jù)編碼、協(xié)議數(shù)據(jù)單元pdu ( protocoldataunite )的封裝以及dicom消息的交換機(jī)制等基本原理。然后概括說(shuō)明了模塊中的協(xié)議數(shù)據(jù)單元、表示數(shù)據(jù)值pdv ( presentationdatavalue ) 、各個(gè)組成條目的封裝以及在程序中為此定義的類(lèi)簇。
According to the trade criterion and the demand of spatial database building , refering to the special database of geological hazard and old database structure , at the same time , considering the specialty of geophysical prospecting data , the author standardizes twenty kinds of geophysical attribute database and the data code and the structure of data table 筆者針對(duì)地質(zhì)災(zāi)害空間數(shù)據(jù)庫(kù)建設(shè)的要求,結(jié)合已有數(shù)據(jù)信息標(biāo)準(zhǔn)的特點(diǎn)和結(jié)構(gòu)以及地質(zhì)災(zāi)害勘查中物探信息的特點(diǎn),對(duì)勘查中常用的二十余種物探方法進(jìn)行了屬性數(shù)據(jù)庫(kù)的標(biāo)準(zhǔn)化建設(shè)。依照物探信息屬性庫(kù)數(shù)據(jù)項(xiàng)編碼規(guī)則,給出屬性表結(jié)構(gòu),并以地質(zhì)災(zāi)害勘查物探方法屬性庫(kù)結(jié)構(gòu)為基礎(chǔ),開(kāi)發(fā)了數(shù)據(jù)管理模塊。
Neural networks are used more frequently in lossy data coding than in general lossless data coding , because standard neural networks must be trained off - line and they are too slow to be practical . in this thesis , statistical language model based on maximum entropy and neural networks are discussed particularly . then , an arithmetic coding algorithm based on maximum entropy and neural networks are proposed in this thesis 傳統(tǒng)的人工神經(jīng)網(wǎng)絡(luò)數(shù)據(jù)編碼算法需要離線(xiàn)訓(xùn)練且編碼速度慢,因此通常多用于專(zhuān)用有損編碼領(lǐng)域如聲音、圖像編碼等,在無(wú)損數(shù)據(jù)編碼領(lǐng)域應(yīng)用較少,針對(duì)這種現(xiàn)狀,本文詳細(xì)地研究了最大熵統(tǒng)計(jì)語(yǔ)言模型和神經(jīng)網(wǎng)絡(luò)算法各自的特點(diǎn),在此基礎(chǔ)上提出了一種基于神經(jīng)網(wǎng)絡(luò)和最大熵原理的算術(shù)編碼方法,這是一種自適應(yīng)的可在線(xiàn)學(xué)習(xí)的算法,并具有精簡(jiǎn)的網(wǎng)絡(luò)結(jié)構(gòu)。
The jpeg compression algorithm takes one kind of highly effective static state image data compression algorithm . the widespread application of jpeg in multitudinous inserted in the type multimedia product the image data code and the decoding speed has already become a most important aspect which the restriction product performance enhanced Jpeg壓縮算法作為一種高效的靜態(tài)圖像數(shù)據(jù)壓縮算法,廣泛的應(yīng)用于眾多的嵌入式多媒體產(chǎn)品中,圖像數(shù)據(jù)編碼和解碼的速度已經(jīng)成了制約產(chǎn)品性能提高的一個(gè)最重要的方面。
Although stb just is a sort of terminal equipments of the tv signal transmission system , however pivotal technique involves the data demodulation , channel decode , transport stream de - multiplexing , audio and video signal decompression technique and real - time software technique with upriver data coding technique etc . therefore , software and hardware technology research and development of stb , which can increase usefulness with dependable of digital video signal and audio signal for study later make the theories preparation and backlog experience 機(jī)頂盒雖然只是數(shù)字電視傳輸系統(tǒng)的終端設(shè)備,但所用到的關(guān)鍵技術(shù)涉及到數(shù)據(jù)解調(diào)、信道解碼、傳輸流的解復(fù)用、音視頻信號(hào)解壓縮技術(shù)以及實(shí)時(shí)軟件技術(shù)和上行數(shù)據(jù)的編碼技術(shù)等。因此,通過(guò)對(duì)機(jī)頂盒軟、硬件的研究開(kāi)發(fā),既能為以后研究如何提高信息傳輸?shù)挠行院涂煽啃宰骼碚撋系臏?zhǔn)備,也為圖像信號(hào)和音頻信號(hào)的數(shù)字化處理積累經(jīng)驗(yàn)。
Based on the super capability of gis , the paper discusses problems on layer management of related data , design of attribute tables , and data coding etc . the coefficient of the soil liquefaction resistance k and the coefficient of soil liquefaction hazard h are presented . the seismic sand liquefaction forecasting , liquefaction disasters forecasting , and prevention measures on liquefaction are also discussed . using the software of mapgis , the process of liquefaction database setup has been studied 本文基于gis在數(shù)據(jù)存儲(chǔ)管理及可視化方面的強(qiáng)大功能,研究了適合gis環(huán)境的液化評(píng)價(jià)相關(guān)數(shù)據(jù)的分層管理,屬性數(shù)據(jù)表設(shè)計(jì)以及圖元編碼等問(wèn)題;并提出了土層抗液化指數(shù)k及砂土液化災(zāi)害指數(shù)h兩個(gè)重要液化評(píng)價(jià)因子,在此基礎(chǔ)上進(jìn)一步研究了地震砂土液化預(yù)測(cè)、液化災(zāi)害預(yù)測(cè)以及防治處理信息系統(tǒng)建設(shè)等問(wèn)題。