Space-time coding radar has been recently proposed and investigated.It is a radar framework which can perform transmit beamforming at the receiver.However,the range resolution decreases when the number of the transmit...Space-time coding radar has been recently proposed and investigated.It is a radar framework which can perform transmit beamforming at the receiver.However,the range resolution decreases when the number of the transmit element increases.A subarray-based space-time coding(sub-STC)radar is explored to alleviate the range resolution reduction.For the proposed radar configuration,an identical waveform is transmitted and it introduces a small time offset in different subarrays.The multidimensional ambiguity function of sub-STC radar is defined by considering resolutions in multiple domains including the range,Doppler,angle and probing direction.Analyses on properties of the multi-dimensional ambiguity function of the sub-STC radar with regard to the spatial coverage,resolution performance and low sidelobes are also given.Results reveal that the range resolution and low sidelobes performance are improved with the proposed approach.展开更多
Chinese-English code-mixing with distinct linguistic features has become prevailing in domestic trademarks in recent three or four decades. The reasons behind this prevalence were left untouched in previous studies. I...Chinese-English code-mixing with distinct linguistic features has become prevailing in domestic trademarks in recent three or four decades. The reasons behind this prevalence were left untouched in previous studies. In this paper, Giddens' modernity theory is used as the theoretical framework to account for the major reason behind the prevalence of Chinese-English codemixing: English code in Chinese business logos plays a positive role as a reflection of China's modernization and her participation in economic globalization.展开更多
Intercepted signal blind separation is a research topic with high importance for both military and civilian communication systems. A blind separation method for space-time block code （STBC） systems is proposed by us...Intercepted signal blind separation is a research topic with high importance for both military and civilian communication systems. A blind separation method for space-time block code （STBC） systems is proposed by using the ordinary independent component analysis （ICA）. This method cannot work when specific complex modulations are employed since the assumption of mutual independence cannot be satisfied. The analysis shows that source signals, which are group-wise independent and use multi-dimensional ICA （MICA） instead of ordinary ICA, can be applied in this case. Utilizing the block-diagonal structure of the cumulant matrices, the JADE algorithm is generalized to the multidimensional case to separate the received data into mutually independent groups. Compared with ordinary ICA algorithms, the proposed method does not introduce additional ambiguities. Simulations show that the proposed method overcomes the drawback and achieves a better performance without utilizing coding information than channel estimation based algorithms.展开更多
This paper proposes a class of novel progressive edge growth-based codebooks for downlink sparse code multiple access(SCMA)systems.In the first scheme,we propose to progressively design the codebooks of each resource ...This paper proposes a class of novel progressive edge growth-based codebooks for downlink sparse code multiple access(SCMA)systems.In the first scheme,we propose to progressively design the codebooks of each resource node(RN)instead of rotating a mother constellation(MC)as in the conventional SCMA works.In the other one,based on the MC,a multi-resources rotated codebooks are proposed to improve the performance of the superimposed constellations.The resultant codebooks are respectively referred to as the resource edge multidimensional codebooks(REMC)and the user edge multi-dimensional codebooks(UEMC).Additionally,we delve into the detailed design of the MC and the superimposed constellation.Then,we pay special attention to the application of the proposed schemes to challenging design cases,particularly for the high dimensional,high rate,and irregular codebooks,where the corresponding simplified schemes are proposed to reduce the complexity of codebook design.Finally,simulation results are presented to demonstrate the superiority of our progressive edge growth-based schemes.The numerical results indicate that the proposed codebooks significantly outperform the stateof-the-art codebooks.In addition,we also show that the proposed REMC codebooks outperform in the lower signal-to-noise ratio(SNR)regime,whereas the UEMC codebooks exhibit better performance at higher SNRs.展开更多
预测性过程监控(predictive process monitoring,PPM)技术通过分析已有的事件日志对正在运行的业务流程中的某些关键指标进行预测.目前的预测性过程监控方法在特征提取方面通常预设案例仅受自身属性的影响或仅通过提取资源案例间行为属...预测性过程监控(predictive process monitoring,PPM)技术通过分析已有的事件日志对正在运行的业务流程中的某些关键指标进行预测.目前的预测性过程监控方法在特征提取方面通常预设案例仅受自身属性的影响或仅通过提取资源案例间行为属性进行编码,通常未涉及活动视角下的案例间行为信息.本文提出了一种捕获活动案例间行为信息的方法IABC(inter-activity behaviour of case),该方法设计了一个三维特征构建框架涵盖时间窗口、活动粒度、行为状态这3大维度,共构造36种活动案例间行为特征.同时,本文提出了两项关键算法:影响力分布算法用于挖掘活动间的正/负影响传播;批次行为检测算法用于识别潜在的批量操作行为.最后在3个公开可用的事件日志上评估IABC方法的有效性,结果表明集成了IABC方法的时间预测模型性能优于未使用该方法的基线模型和采用了资源案例间特征的模型.展开更多
基金supported by the National Key Research and Development Program of China(2016YFE0200400)the Key R&D Program of Shaanxi Province(2017KW-ZD-12)+1 种基金the Postdoctoral Science Foundation of Shaanxi Provincethe Nature Science Foundation of Shaanxi Province
文摘Space-time coding radar has been recently proposed and investigated.It is a radar framework which can perform transmit beamforming at the receiver.However,the range resolution decreases when the number of the transmit element increases.A subarray-based space-time coding(sub-STC)radar is explored to alleviate the range resolution reduction.For the proposed radar configuration,an identical waveform is transmitted and it introduces a small time offset in different subarrays.The multidimensional ambiguity function of sub-STC radar is defined by considering resolutions in multiple domains including the range,Doppler,angle and probing direction.Analyses on properties of the multi-dimensional ambiguity function of the sub-STC radar with regard to the spatial coverage,resolution performance and low sidelobes are also given.Results reveal that the range resolution and low sidelobes performance are improved with the proposed approach.
文摘Chinese-English code-mixing with distinct linguistic features has become prevailing in domestic trademarks in recent three or four decades. The reasons behind this prevalence were left untouched in previous studies. In this paper, Giddens' modernity theory is used as the theoretical framework to account for the major reason behind the prevalence of Chinese-English codemixing: English code in Chinese business logos plays a positive role as a reflection of China's modernization and her participation in economic globalization.
基金supported by the National Natural Science Foundation of China (61201282)
文摘Intercepted signal blind separation is a research topic with high importance for both military and civilian communication systems. A blind separation method for space-time block code （STBC） systems is proposed by using the ordinary independent component analysis （ICA）. This method cannot work when specific complex modulations are employed since the assumption of mutual independence cannot be satisfied. The analysis shows that source signals, which are group-wise independent and use multi-dimensional ICA （MICA） instead of ordinary ICA, can be applied in this case. Utilizing the block-diagonal structure of the cumulant matrices, the JADE algorithm is generalized to the multidimensional case to separate the received data into mutually independent groups. Compared with ordinary ICA algorithms, the proposed method does not introduce additional ambiguities. Simulations show that the proposed method overcomes the drawback and achieves a better performance without utilizing coding information than channel estimation based algorithms.
文摘This paper proposes a class of novel progressive edge growth-based codebooks for downlink sparse code multiple access(SCMA)systems.In the first scheme,we propose to progressively design the codebooks of each resource node(RN)instead of rotating a mother constellation(MC)as in the conventional SCMA works.In the other one,based on the MC,a multi-resources rotated codebooks are proposed to improve the performance of the superimposed constellations.The resultant codebooks are respectively referred to as the resource edge multidimensional codebooks(REMC)and the user edge multi-dimensional codebooks(UEMC).Additionally,we delve into the detailed design of the MC and the superimposed constellation.Then,we pay special attention to the application of the proposed schemes to challenging design cases,particularly for the high dimensional,high rate,and irregular codebooks,where the corresponding simplified schemes are proposed to reduce the complexity of codebook design.Finally,simulation results are presented to demonstrate the superiority of our progressive edge growth-based schemes.The numerical results indicate that the proposed codebooks significantly outperform the stateof-the-art codebooks.In addition,we also show that the proposed REMC codebooks outperform in the lower signal-to-noise ratio(SNR)regime,whereas the UEMC codebooks exhibit better performance at higher SNRs.
文摘预测性过程监控(predictive process monitoring,PPM)技术通过分析已有的事件日志对正在运行的业务流程中的某些关键指标进行预测.目前的预测性过程监控方法在特征提取方面通常预设案例仅受自身属性的影响或仅通过提取资源案例间行为属性进行编码,通常未涉及活动视角下的案例间行为信息.本文提出了一种捕获活动案例间行为信息的方法IABC(inter-activity behaviour of case),该方法设计了一个三维特征构建框架涵盖时间窗口、活动粒度、行为状态这3大维度,共构造36种活动案例间行为特征.同时,本文提出了两项关键算法:影响力分布算法用于挖掘活动间的正/负影响传播;批次行为检测算法用于识别潜在的批量操作行为.最后在3个公开可用的事件日志上评估IABC方法的有效性,结果表明集成了IABC方法的时间预测模型性能优于未使用该方法的基线模型和采用了资源案例间特征的模型.
