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在人口众多、人均资源严重不足的中国,能源不足与经济发展的矛盾突出,太阳能是理想的可再生能源,太阳能发电对解决我国电力能源短缺意义重大.敦煌铁路中太阳能电站已经建成并投入使用,运行良好,且具有很好的经济和社会效益. 相似文献
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知识经济与信息经济就如同知识与信息一样,逐渐地被人们认识、讨论、发展。近些年来,知识经济与信息经济被越来越多的人所关注,在社会发展中扮演着重要角色。首先,让我们抓住知识与信息的产生、发展过程,然后,我们就可以对知识经济与信息经济有清晰地认识。 相似文献
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A fuzzy clustering analysis based phonetic tied-mixture HMM (FPTM) was presented to decrease parameter size and improve robustness of parameter training. FPTM was synthesized from state-tied HMMs by a modified fuzzy C-means clustering algorithm. Each Gaussian codebook of FPTM was built from Gaussian components within the same root node in phonetic decision tree. The experimental results on large vocabulary Mandarin speech recognition show that compared with conventional phonetic tied-mixture HMM and state-tied HMM with approximately the same number of Gaussian mixtures, FPTM achieves word error rate reductions by 4.84% and 13.02% respectively. Combining the two schemes of mixing weights pruning and Gaussian centers fuzzy merging, a significantly parameter size reduction was achieved with little impact on recognition accuracy. 相似文献
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OAM (Operations, Administration and Maintenance) system is a very important component of 3G cellular network. In order to acquire overall management, fast response and steady operation, an SCTP (Stream Control Transmission Protocol) based OAM, i. e. , SOAM system was proposed. SOAM implements new characters of SCTP such as multi-stream, enforced SACK and heartbeat mechanism on its transport layer. These characters help SOAM decrease the message transmission delay and accelerate the link failure detection. Besides, a new component named SOAM agent was introduced to improve the operation efficiency of SOAM. The experimental results prove the proposed SOAM system achieves better performance on signaling transmission compared with conventional TCP based OAM system. 相似文献
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IntroductionFuture mobile communication network willconsist of multiple traffics and access technologies.It is to certainty a radio heterogeneous network(RHN) because none of the current networks canprovide ubiquitous coverage and all-around ser-vices[1]. Future mobile terminal will be multi-modethat maintains connectivity to different radio accesspoints, so RHN should be scalable and support theevolution and upgrade of individual network ele-ments. All-IP architecture is an inevitable way… 相似文献
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