Generalised pre-coding quadrature spatial modulation(GPQSM)is recently proposed to increase the spectral efficiency(SE)of GPSM,which extends the transmitted symbols into in-phase/quadrature domains.In this paper,a nov...Generalised pre-coding quadrature spatial modulation(GPQSM)is recently proposed to increase the spectral efficiency(SE)of GPSM,which extends the transmitted symbols into in-phase/quadrature domains.In this paper,a novel scheme named non-orthogonal multiple access(NOMA)-aided GPQSM(NOMA-GPQSM),which incorporates the GPQSM scheme into the multi-user communication networks with assist of NOMA,is proposed to further improve the SE and system performance.In NOMA-GPQSM,one base station(BS)is set to serve K users,where user 1 is closest to the BS,and user K is farthest from the BS.In addition,a low-complexity detection method is proposed to reduce the high detection complexity of the maximum-likelihood(ML)detection in successive interference cancellation(SIC)method for all users by NOMA-GPQSM.The theoretical analysis of the BER performance for all users is also derived.Simulation results show that near users achieve relatively good performance,and far users achieve acceptable performance by adjusting power factors for all users in NOMA-GPQSM.展开更多
针对国际疾病分类(ICD)自动编码方法的长文本处理、编码的层次结构以及长尾分布等导致的模型泛化能力弱的问题,提出一种充分利用医学预训练语言模型的基于提示学习和超球原型的小样本ICD自动编码方法(hypersphere prototypical with pro...针对国际疾病分类(ICD)自动编码方法的长文本处理、编码的层次结构以及长尾分布等导致的模型泛化能力弱的问题,提出一种充分利用医学预训练语言模型的基于提示学习和超球原型的小样本ICD自动编码方法(hypersphere prototypical with prompt learning,PromptHP)。首先,将编码描述与临床文本融合进提示学习模型中的提示模板,使得模型能够更加深入地理解临床文本;然后,充分利用预训练语言模型的先验知识进行初始预测;接着,在预训练语言模型输出表示的基础上引入超球原型进行类别建模和度量分类,并在医学数据集上微调网络,充分纳入数据知识,提高模型在小样本ICD编码分配任务上的性能;最后,对以上两部分预测结果集成加权获得最终编码预测结果。在公开医学数据集MIMIC-Ⅲ上的实验结果表明,该模型优于最先进的基线方法,PromptHP将小样本编码的macro-AUC、micro-AUC、macro-F_(1)和micro-F_(1)分别提高了1.77%、1.54%、14.22%、15.01%。实验结果验证了该模型在小样本编码分类任务中的有效性。展开更多
Pre-coding aided quadrature spatial modulation(PQSM) is a promising multiple input multiple output(MIMO) transmission technology. The multiuser(MU) detection in PQSM system is investigated in this paper. Based on the ...Pre-coding aided quadrature spatial modulation(PQSM) is a promising multiple input multiple output(MIMO) transmission technology. The multiuser(MU) detection in PQSM system is investigated in this paper. Based on the known channel state information, pre-coding matrix is designed to pre-process the in-phase and quadrature signals of quadrature spatial modulation(QSM) to reduce the inter-channel interference. In order to lower the complexity at the receiver brought by the orthogonality of the PQSM system, an orthogonal matching pursuit(OMP) detection algorithm and a reconstructed model are proposed. The analysis and simulation results show that the proposed algorithm can obtain a similar bit error rate(BER) performance as the maximum likelihood(ML) detection algorithm with more than 80% reduction of complexity.展开更多
为了降低低密度奇偶校验(Low Density Parity Check,LDPC)码译码算法的复杂度,提出了一种基于量化预处理的LDPC迭代大数逻辑译码算法。该算法在迭代译码过程中,校验节点采用基于伴随式的信息处理方式,避免了外信息的计算;同时,变量节点...为了降低低密度奇偶校验(Low Density Parity Check,LDPC)码译码算法的复杂度,提出了一种基于量化预处理的LDPC迭代大数逻辑译码算法。该算法在迭代译码过程中,校验节点采用基于伴随式的信息处理方式,避免了外信息的计算;同时,变量节点基于回传的伴随式信息进行可靠度偏移大小的计算,并结合与当前码位相对应的调制映射信息进行可靠度偏移方向的设计。迭代更新时,变量节点采用基于信息匹配的可靠度更新规则。迭代前的量化预处理能避免实数乘法运算进入迭代过程,使其只涉及整数加法操作和逻辑操作。仿真结果表明,在保持译码性能的前提上,所提算法具有更低的译码复杂度。展开更多
针对目前自动ICD(international classification of diseases)编码任务存在标签空间大、诊断代码分布不均衡与临床文本表征差的问题,提出一种融合Longformer与标签注意力的分层ICD自动编码模型。借助Clinical-Longformer预训练语言模型...针对目前自动ICD(international classification of diseases)编码任务存在标签空间大、诊断代码分布不均衡与临床文本表征差的问题,提出一种融合Longformer与标签注意力的分层ICD自动编码模型。借助Clinical-Longformer预训练语言模型获得融合长文本语境的词向量表征。通过将标签的语义表示与注意力机制相结合,捕捉临床文本中与诊断代码相关的关键特征信息,获取更精准的文本表示。引入分层联合学习机制,建立分层预测层解码输出ICD编码。实验结果表明,该模型的准确率、召回率与F1值均高于现有模型,验证了该方法进行自动ICD编码的有效性,为实施疾病诊断相关分组提供高质量的数据支撑。展开更多
基金supported by National Nature Science Foundation of China(No.61701127,No.61871139,No.61631004,No.62071319)the International Collaborative Research Program of Guangdong Science and Technology Department(No.2020A0505100061).
文摘Generalised pre-coding quadrature spatial modulation(GPQSM)is recently proposed to increase the spectral efficiency(SE)of GPSM,which extends the transmitted symbols into in-phase/quadrature domains.In this paper,a novel scheme named non-orthogonal multiple access(NOMA)-aided GPQSM(NOMA-GPQSM),which incorporates the GPQSM scheme into the multi-user communication networks with assist of NOMA,is proposed to further improve the SE and system performance.In NOMA-GPQSM,one base station(BS)is set to serve K users,where user 1 is closest to the BS,and user K is farthest from the BS.In addition,a low-complexity detection method is proposed to reduce the high detection complexity of the maximum-likelihood(ML)detection in successive interference cancellation(SIC)method for all users by NOMA-GPQSM.The theoretical analysis of the BER performance for all users is also derived.Simulation results show that near users achieve relatively good performance,and far users achieve acceptable performance by adjusting power factors for all users in NOMA-GPQSM.
文摘针对国际疾病分类(ICD)自动编码方法的长文本处理、编码的层次结构以及长尾分布等导致的模型泛化能力弱的问题,提出一种充分利用医学预训练语言模型的基于提示学习和超球原型的小样本ICD自动编码方法(hypersphere prototypical with prompt learning,PromptHP)。首先,将编码描述与临床文本融合进提示学习模型中的提示模板,使得模型能够更加深入地理解临床文本;然后,充分利用预训练语言模型的先验知识进行初始预测;接着,在预训练语言模型输出表示的基础上引入超球原型进行类别建模和度量分类,并在医学数据集上微调网络,充分纳入数据知识,提高模型在小样本ICD编码分配任务上的性能;最后,对以上两部分预测结果集成加权获得最终编码预测结果。在公开医学数据集MIMIC-Ⅲ上的实验结果表明,该模型优于最先进的基线方法,PromptHP将小样本编码的macro-AUC、micro-AUC、macro-F_(1)和micro-F_(1)分别提高了1.77%、1.54%、14.22%、15.01%。实验结果验证了该模型在小样本编码分类任务中的有效性。
基金partially supported by the National Natural Science Foundation of China (Grant No. 61701063)Scientific and Technological Research Program of Chongqing Municipal Education Commission (No. KJ1600435)
文摘Pre-coding aided quadrature spatial modulation(PQSM) is a promising multiple input multiple output(MIMO) transmission technology. The multiuser(MU) detection in PQSM system is investigated in this paper. Based on the known channel state information, pre-coding matrix is designed to pre-process the in-phase and quadrature signals of quadrature spatial modulation(QSM) to reduce the inter-channel interference. In order to lower the complexity at the receiver brought by the orthogonality of the PQSM system, an orthogonal matching pursuit(OMP) detection algorithm and a reconstructed model are proposed. The analysis and simulation results show that the proposed algorithm can obtain a similar bit error rate(BER) performance as the maximum likelihood(ML) detection algorithm with more than 80% reduction of complexity.
文摘为了降低低密度奇偶校验(Low Density Parity Check,LDPC)码译码算法的复杂度,提出了一种基于量化预处理的LDPC迭代大数逻辑译码算法。该算法在迭代译码过程中,校验节点采用基于伴随式的信息处理方式,避免了外信息的计算;同时,变量节点基于回传的伴随式信息进行可靠度偏移大小的计算,并结合与当前码位相对应的调制映射信息进行可靠度偏移方向的设计。迭代更新时,变量节点采用基于信息匹配的可靠度更新规则。迭代前的量化预处理能避免实数乘法运算进入迭代过程,使其只涉及整数加法操作和逻辑操作。仿真结果表明,在保持译码性能的前提上,所提算法具有更低的译码复杂度。
文摘针对目前自动ICD(international classification of diseases)编码任务存在标签空间大、诊断代码分布不均衡与临床文本表征差的问题,提出一种融合Longformer与标签注意力的分层ICD自动编码模型。借助Clinical-Longformer预训练语言模型获得融合长文本语境的词向量表征。通过将标签的语义表示与注意力机制相结合,捕捉临床文本中与诊断代码相关的关键特征信息,获取更精准的文本表示。引入分层联合学习机制,建立分层预测层解码输出ICD编码。实验结果表明,该模型的准确率、召回率与F1值均高于现有模型,验证了该方法进行自动ICD编码的有效性,为实施疾病诊断相关分组提供高质量的数据支撑。
