有线网数字电视广播中各个城市传送流的物理参数都不一样,标准的网络信息表(Network Information Table,NIT)传送到各个城市后参数不可修改,因此提出了修改NIT表以适应多城市的数字电视广播。 (1)原先数字电视广播中存在的问题。各省在...有线网数字电视广播中各个城市传送流的物理参数都不一样,标准的网络信息表(Network Information Table,NIT)传送到各个城市后参数不可修改,因此提出了修改NIT表以适应多城市的数字电视广播。 (1)原先数字电视广播中存在的问题。各省在有线网进行数字电视广播时都是通过省内的SDH光纤网络将数字信号送到各地市有线电视前端,在有线电视前端分别使用QAM调制器将数字信号调制成模拟RF信号后送到HFC网络传输。此方案在实施过程中存在问题。展开更多
本文提出了一种动态的电视台台标显示方法。该方法通过在数字电视机顶盒(STB,Set Top Box)端预置电视台指定的台标图案,再通过网络信息表(NIT,Network Information Table)所携带的私有描述子(descriptor)发送每个节目对应的台标及其在...本文提出了一种动态的电视台台标显示方法。该方法通过在数字电视机顶盒(STB,Set Top Box)端预置电视台指定的台标图案,再通过网络信息表(NIT,Network Information Table)所携带的私有描述子(descriptor)发送每个节目对应的台标及其在电视屏幕上的显示位置信息,使用户终端STB根据相关信息利用屏幕显示(OSD,On Screen Display)将内置的台标显示在指定位置。展开更多
Background Nicorandil （NIC） is a vasodilatory drug used to treat angina. However, its efficacy of cardioprotection in coronary mi- croembolization （CME） is largely unknown. This study was undertaken to determine w...Background Nicorandil （NIC） is a vasodilatory drug used to treat angina. However, its efficacy of cardioprotection in coronary mi- croembolization （CME） is largely unknown. This study was undertaken to determine whether nicorandil pretreatment could attenuate myo- cardial apoptosis and improve cardiac function after CME in rats. Methods Forty-five rats were randomly divided into a Sham group, a CME group and a CME ＋ NIC （NIC） group （n = 15 per group）. CME was established by injecting plastic microspheres （42 pm in diameter） into the left ventricle of the rats in all of the groups except the Sham group. The NIC group received nicorandil at 3 mg/kg per day for seven days before the operation. Cardiac fimction was assessed by echocardiography, the expression levels of cleaved caspase-9/8/3 were detected by Western blot, microinfarction area was measured by haematoxylin-basic fuchsin picric acid staining, and myocardial apoptosis was de- tected by TUNEL staining. Results Compared to that in the Sham group, cardiac fimction in the CME group was significantly decreased （P 〈 0.05）. However, compared to the CME group, the NIC group showed improved cardiac function （P 〈 0.05）. The expression levels of cleaved caspase-9/8/3 protein and myocardial apoptosis were dramatically increased in the CME group compared to those in the Sham group （P 〈 0.05）, while the NIC pretreatment group had significantly decreased expression levels of cleaved caspase-9/8/3 protein as well as a de- creased apoptotic rate （P 〈 0.05）. Conclusions NIC pretreatment inhibited CME-induced myocardial apoptosis and improved cardiac func- tion through blockade of the mitochondrial and death receptor-mediated apoptotic pathways.展开更多
Based on the massive data collected with a passive network monitoring equipment placed in China＇s backbone, we present a deep insight into the network backbone traffic and evaluate various ways for inproving traffic ...Based on the massive data collected with a passive network monitoring equipment placed in China＇s backbone, we present a deep insight into the network backbone traffic and evaluate various ways for inproving traffic classifying efficiency in this pa- per. In particular, the study has scrutinized the net- work traffic in terms of protocol types and signatures, flow length, and port distffoution, from which mean- ingful and interesting insights on the current Intemet of China from the perspective of both the packet and flow levels are derived. We show that the classifica- tion efficiency can be greatly irrproved by using the information of preferred ports of the network applica- tions. Quantitatively, we find two traffic duration thresholds, with which 40% of TCP flows and 70% of UDP flows can be excluded from classification pro- cessing while the in^act on classification accuracy is trivial, i.e., the classification accuracy can still reach a high level by saving 85% of the resources.展开更多
With the application of modem information technology in education, particularly after multimedia network technology enters teaching field of education, the content of education, the content and the means of education ...With the application of modem information technology in education, particularly after multimedia network technology enters teaching field of education, the content of education, the content and the means of education has undergone great changes.In order to develop complex English talent, we designed a teaching model of English reading as a means of multimedia assisted teaching through collaborative, exploratory, autonomous interactive teaching, which can fully exercise and develop students＇ language skills, improving English quality of teaching.It has changed the traditional teaching model which is constrined bye teacher-centered, textbook-centered, classroom-centered. Multimedia Assisted English reading can give students the greatest degree of autonomy, and pay more attention to students＇ learning ability to play the main role in the cognitive, reflectting the idea of quality education, meetting the requirements of the times.展开更多
文摘有线网数字电视广播中各个城市传送流的物理参数都不一样,标准的网络信息表(Network Information Table,NIT)传送到各个城市后参数不可修改,因此提出了修改NIT表以适应多城市的数字电视广播。 (1)原先数字电视广播中存在的问题。各省在有线网进行数字电视广播时都是通过省内的SDH光纤网络将数字信号送到各地市有线电视前端,在有线电视前端分别使用QAM调制器将数字信号调制成模拟RF信号后送到HFC网络传输。此方案在实施过程中存在问题。
文摘本文提出了一种动态的电视台台标显示方法。该方法通过在数字电视机顶盒(STB,Set Top Box)端预置电视台指定的台标图案,再通过网络信息表(NIT,Network Information Table)所携带的私有描述子(descriptor)发送每个节目对应的台标及其在电视屏幕上的显示位置信息,使用户终端STB根据相关信息利用屏幕显示(OSD,On Screen Display)将内置的台标显示在指定位置。
基金This work received the support of the National Natural Science Foundation of China （Grant No. 81600283） and the Guangxi Natural Science Foundation （Grant No. 2016 GXNSFBA380022）.
文摘Background Nicorandil （NIC） is a vasodilatory drug used to treat angina. However, its efficacy of cardioprotection in coronary mi- croembolization （CME） is largely unknown. This study was undertaken to determine whether nicorandil pretreatment could attenuate myo- cardial apoptosis and improve cardiac function after CME in rats. Methods Forty-five rats were randomly divided into a Sham group, a CME group and a CME ＋ NIC （NIC） group （n = 15 per group）. CME was established by injecting plastic microspheres （42 pm in diameter） into the left ventricle of the rats in all of the groups except the Sham group. The NIC group received nicorandil at 3 mg/kg per day for seven days before the operation. Cardiac fimction was assessed by echocardiography, the expression levels of cleaved caspase-9/8/3 were detected by Western blot, microinfarction area was measured by haematoxylin-basic fuchsin picric acid staining, and myocardial apoptosis was de- tected by TUNEL staining. Results Compared to that in the Sham group, cardiac fimction in the CME group was significantly decreased （P 〈 0.05）. However, compared to the CME group, the NIC group showed improved cardiac function （P 〈 0.05）. The expression levels of cleaved caspase-9/8/3 protein and myocardial apoptosis were dramatically increased in the CME group compared to those in the Sham group （P 〈 0.05）, while the NIC pretreatment group had significantly decreased expression levels of cleaved caspase-9/8/3 protein as well as a de- creased apoptotic rate （P 〈 0.05）. Conclusions NIC pretreatment inhibited CME-induced myocardial apoptosis and improved cardiac func- tion through blockade of the mitochondrial and death receptor-mediated apoptotic pathways.
基金This paper was partially supported by the National Natural Science Foundation of China under Crant No. 61072061111 Project of China under Crant No. B08004 the Fundamental Research Funds for the Central Universities under Grant No. 2009RC0122. References
文摘Based on the massive data collected with a passive network monitoring equipment placed in China＇s backbone, we present a deep insight into the network backbone traffic and evaluate various ways for inproving traffic classifying efficiency in this pa- per. In particular, the study has scrutinized the net- work traffic in terms of protocol types and signatures, flow length, and port distffoution, from which mean- ingful and interesting insights on the current Intemet of China from the perspective of both the packet and flow levels are derived. We show that the classifica- tion efficiency can be greatly irrproved by using the information of preferred ports of the network applica- tions. Quantitatively, we find two traffic duration thresholds, with which 40% of TCP flows and 70% of UDP flows can be excluded from classification pro- cessing while the in^act on classification accuracy is trivial, i.e., the classification accuracy can still reach a high level by saving 85% of the resources.
文摘With the application of modem information technology in education, particularly after multimedia network technology enters teaching field of education, the content of education, the content and the means of education has undergone great changes.In order to develop complex English talent, we designed a teaching model of English reading as a means of multimedia assisted teaching through collaborative, exploratory, autonomous interactive teaching, which can fully exercise and develop students＇ language skills, improving English quality of teaching.It has changed the traditional teaching model which is constrined bye teacher-centered, textbook-centered, classroom-centered. Multimedia Assisted English reading can give students the greatest degree of autonomy, and pay more attention to students＇ learning ability to play the main role in the cognitive, reflectting the idea of quality education, meetting the requirements of the times.
