cI|: null 1673null9965( 2011) 01null078null06BjSed!9LC*杨永侠, 何波( T1 ,?9vIntra_4null 4T4;nullKV?T/NflIntra_16null 16vKDTCost16null 16,5|KV?79null1null null null null null null null null null null null null-等:BjSed!9LCTT-vKDT;null5,Intra_4 null 4vT4,|5/:a)TIntra _ 16 null 16KDTMo de0(.3TL inuxmSed!9 J .9C, 2010( 11) : 31.null null TA NG Rennullcai, LIU L iannullhao. Design of Remote Imag eM onitoring System Based on Embedded L inux J . Co mnullputer and M odernizat ion, 2010( 11) : 31. ( in Chinese) 4 nullB,.mi%T) J ., 2005( 9) : 39.null null LI U Shinullde, WEI Bin. T he Discussiong and A pplicanullt ion o f Online T ransmission Imag e St orag e Fo rmats J . Pr int T o day , 2005( 9) : 39. ( in Chinese) 5 null,7?.3jSedZLC J .93, 2008, 38( 9) : 161.null null PA N G M aonullqun, DEN G K ainullfa. Realization of ClientSy stem in Digital V ideo Sur veillance J . Co mputer &Digital Engineering, 2008, 38( 9) : 161. ( in Chinese) 6 nullfL,f;,f.KDSP/null null null nullronulldaOFq M .:S,S,.jSed!9LC J .9, 2009, 25( 1/ 3) : 129.null null L IU Yun, L U Shaonullto ng , ZH OU L iang. T he Desig nof V ideo M o nitor ing System J . M icroco mputer Imnullfo rmation, 2009, 25( 1/ 3) : 129. ( in Chinese)82 null null null null null null null null null null null nullnullnullnullnullvnullnullnullnull null null null null null null null null null null null null null null31Design of a NewNetworkVideo MonitoringSystemYAN G Yongnullxia , H E Bo( Schoo l of Elect ronic Infor matio n Engineer ing, Xinull an T echnolog ical U niver sity , Xinull an 710032, China)Abstract: null Because the tr aditional vedio monito ring system has the w eaknesses of a larg e amo unt o fcom putation and poor realnulltime perfo rmance, an embedded H . 264 mo nitoring sy stem is presented. WithTM S 320DM 6467 and the em bedded linux operation system as the platfor m, H . 264 co mpress algor ithmis studied by using Davinci techno logy . Based on the hardw are platfo rm, the improved H . 264 co mpressalgorithm is verified, and the netw o rk video monito ring system hardw ar e platfo rm is designed. T hecom pressed images by the traditional and im pr oved H . 264 compress alg orithm s are analyzed. T he resultsindicate that the impr oved algorithm can decrease the am ounts of co mputatio n and increase the encodingspeed by 30% w ith satisfacto ry encoding quality and efficiency , thus im prov ing the real time tr ansmissio nof the video monito ring system.Keywords: null H . 264 com pression algo rithms; netw or k vedio; m onitor ing sy stem; dav inci technolo gy(责任编辑a校对null 苗静)(上接第77页)ResearchonGridnullconnected ControlBasedonSPWM Current TrackGA O Song , WA NG H ui , H E N ing , CH EN Chaonullbo( Schoo l of Elect ronic Infor matio n Engineer ing, Xinull an T echnolog ical U niver sity , Xinull an 710032, China)Abstract: null T he tr aditional SPWM inverter control method of the current tracking inter connection hasthe disadvantag es o f low er curr ent, big ger follow error and liability to being affected by netw ork voltage.An improved SPWM curr ent instantaneous tracking contro l metho d is pr opo sed. T he sing lenullphase g ridinverter circuit topolog y is introduced first. T hen the modified SPWM current contr ol m odes ar edescribed and analy zed, and the mathem atical m odel of the g rid current closednullloo p co ntrol system isestablished. Finally , the improved SPWM current contr ol mode w as simulated. Simulation results showthat the co ntent of harm onic distor tio n is significantly r educed w hile the r ealnulltim e perfo rmance is gr eatlyimpr oved.Keywords: null g ridnullconnected inv erter; cur rent tracking control; SPWM; harm onic distortion(责任编辑a校对null 张立新)83null1null null null null null null null null null null null null-等:BjSed!9LC