Wireless capsule endoscopy(WCE) is a promising technique which has overcome some limitations of traditional diagnosing tools, such as the comfortlessness of the cables and the inability of examining small intestine se...Wireless capsule endoscopy(WCE) is a promising technique which has overcome some limitations of traditional diagnosing tools, such as the comfortlessness of the cables and the inability of examining small intestine section. However, this technique is still far from mature and asks for the feasible improvements. For example, the relatively low transmission data rate and the absence of the real-time localization information of the capsule are all important issues. The studies of them rely on the understanding of the electromagnetic wave propagation in human body. Investigation of performance of WCE communication system was carried out by studying electromagnetic(EM) wave propagation of the wireless capsule endoscopy transmission channel. Starting with a pair of antennas working in a human body mimic environment, the signal transmissions and attenuations were examined. The relationship between the signal attenuation and the capsule(transmitter) position, and direction was also evaluated. These results provide important information for real-time localization of the capsule. Moreover, the pair of antennas and the human body were treated as a transmission channel, on which the binary amplitude shift keying(BASK) modulation scheme was used. The relationship between the modulation scheme, data rate and bit error rate was also determined in the case of BASK. With the obtained studies, it make possible to provide valuable information for further studies on the selection of the modulation scheme and the real-time localization of the capsules.展开更多
重要输电通道风险评估和预测对状态检修和线路运维工作具有指导性意义,而采用传统长短时记忆(long and short-term memory,LSTM)网络对线路风险进行预测时,人为调参困难、预测精度较低,因此,提出了一种基于水波优化-因子分析-长短时记忆...重要输电通道风险评估和预测对状态检修和线路运维工作具有指导性意义,而采用传统长短时记忆(long and short-term memory,LSTM)网络对线路风险进行预测时,人为调参困难、预测精度较低,因此,提出了一种基于水波优化-因子分析-长短时记忆(water wave optimization-factor analysis-long and short-term memory,WWO-FALSTM)的重要输电通道风险准确评估与快速预测方法。首先,引入Levy分布、高斯–柯西变异算子和线性递减波高对WWO进行改进;其次,获取评估区多维致灾因子,并进行FA降维后作为网络输入,考虑孕灾环境敏感性和承灾体易损性计算出风险指数Rc作为网络输出;通过改进的WWO对LSTM进行不断优化,得到最优化LSTM模型;最后,采用最优化LSTM模型对重要输电通道进行风险预测。结果表明,该模型风险评估准确,模型预测较传统方法降低了误差,适用于输电通道风险评估与预测。展开更多
基金Projects(BK2011352,BK20131183) partially supported by the Natural Science Foundation of Jiangsu Province,ChinaProjects(SYG201011,SYG201211) supported by Suzhou Science and Technology Bureau,ChinaProject(10-03-16) supported by Xi’an Jiaotong-Liverpool University Research Development Fund,China
文摘Wireless capsule endoscopy(WCE) is a promising technique which has overcome some limitations of traditional diagnosing tools, such as the comfortlessness of the cables and the inability of examining small intestine section. However, this technique is still far from mature and asks for the feasible improvements. For example, the relatively low transmission data rate and the absence of the real-time localization information of the capsule are all important issues. The studies of them rely on the understanding of the electromagnetic wave propagation in human body. Investigation of performance of WCE communication system was carried out by studying electromagnetic(EM) wave propagation of the wireless capsule endoscopy transmission channel. Starting with a pair of antennas working in a human body mimic environment, the signal transmissions and attenuations were examined. The relationship between the signal attenuation and the capsule(transmitter) position, and direction was also evaluated. These results provide important information for real-time localization of the capsule. Moreover, the pair of antennas and the human body were treated as a transmission channel, on which the binary amplitude shift keying(BASK) modulation scheme was used. The relationship between the modulation scheme, data rate and bit error rate was also determined in the case of BASK. With the obtained studies, it make possible to provide valuable information for further studies on the selection of the modulation scheme and the real-time localization of the capsules.
文摘重要输电通道风险评估和预测对状态检修和线路运维工作具有指导性意义,而采用传统长短时记忆(long and short-term memory,LSTM)网络对线路风险进行预测时,人为调参困难、预测精度较低,因此,提出了一种基于水波优化-因子分析-长短时记忆(water wave optimization-factor analysis-long and short-term memory,WWO-FALSTM)的重要输电通道风险准确评估与快速预测方法。首先,引入Levy分布、高斯–柯西变异算子和线性递减波高对WWO进行改进;其次,获取评估区多维致灾因子,并进行FA降维后作为网络输入,考虑孕灾环境敏感性和承灾体易损性计算出风险指数Rc作为网络输出;通过改进的WWO对LSTM进行不断优化,得到最优化LSTM模型;最后,采用最优化LSTM模型对重要输电通道进行风险预测。结果表明,该模型风险评估准确,模型预测较传统方法降低了误差,适用于输电通道风险评估与预测。
