In this paper,average bit error probability(ABEP)bound of optimal maximum likelihood(ML)detector is first derived for ultra massive(UM)multiple-input-multiple-output(MIMO)system with generalized amplitude phase modula...In this paper,average bit error probability(ABEP)bound of optimal maximum likelihood(ML)detector is first derived for ultra massive(UM)multiple-input-multiple-output(MIMO)system with generalized amplitude phase modulation(APM),which is confirmed by simulation results.Furthermore,a minimum residual criterion(MRC)based lowcomplexity near-optimal ML detector is proposed for UM-MIMO system.Specifically,we first obtain an initial estimated signal by a conventional detector,i.e.,matched filter(MF),or minimum mean square error(MMSE)and so on.Furthermore,MRC based error correction mechanism(ECM)is proposed to correct the erroneous symbol encountered in the initial result.Simulation results are shown that the performance of the proposed MRC-ECM based detector is capable of approaching theoretical ABEP of ML,despite only imposing a slightly higher complexity than that of the initial detector.展开更多
In market economy,SNA(A System of National Accounts),GFS(A System of Government Finance Statistics)and MFS(Money Finance Summery)are the important tools in management of macro-economy In this paper,a comparison of SNA...In market economy,SNA(A System of National Accounts),GFS(A System of Government Finance Statistics)and MFS(Money Finance Summery)are the important tools in management of macro-economy In this paper,a comparison of SNA,GFS and MFS were made on the accounting rule,the accounting structure and the accounting general framework,and a analysis were made on the accounting body,the accounting objective,the system of indicators,the standard classification and the full accounts.展开更多
文章提出了一种新的基于MFS法(Method of Fundamental Solutions,即基本解法)的求解船舶势流问题的无网格数值方法。该方法采用势流控制方程的基本解表达流场中的速度势,可以得到任意阶连续的速度势导数;另外,通过引入流场虚边界的概念...文章提出了一种新的基于MFS法(Method of Fundamental Solutions,即基本解法)的求解船舶势流问题的无网格数值方法。该方法采用势流控制方程的基本解表达流场中的速度势,可以得到任意阶连续的速度势导数;另外,通过引入流场虚边界的概念避免了传统边界元方法中存在奇点的问题。相比传统的边界元方法,MFS法具有无奇性、不依赖网格、不涉及数值积分、数学原理简单和算法易于编程实现的优势。文中对于MFS法在求解浅水二维剖面水动力系数中的应用进行了探索,提出了一套实用的数值算法,并进一步结合频域切片法计算了Wigley船体的垂荡和纵摇响应,通过和频域面元法及试验结果的对比验证了方法的正确性和实用性;最后应用开发的程序分析了不同水深和航速对于耐波性的影响。该研究开创性地将MFS方法应用到了船舶水动力研究领域,为之后更深入广泛地应用这一特性优良的数值方法提供了有益的参考。展开更多
针对现有皮肤镜图像分割技术分割精度不高的问题,提出了一种基于多尺度信息提取和特征融合的U型网络(multi-scale information extraction and feature fusion U-shaped network,MF-UNet)模型。在U-Net的基础上,在卷积层后加入批归一化...针对现有皮肤镜图像分割技术分割精度不高的问题,提出了一种基于多尺度信息提取和特征融合的U型网络(multi-scale information extraction and feature fusion U-shaped network,MF-UNet)模型。在U-Net的基础上,在卷积层后加入批归一化层,将原本的跳跃连接部分替换为4级特征融合模块,充分利用语义信息和位置信息,在特征提取端末尾加入多尺度空洞卷积模块和多尺度池化模块,增大感受野,利用双路拼接上采样模块进行上采样,减少图像恢复过程中的信息损失。实验表明,相较于U-Net模型,MF-UNet在平均交并比(mean intersection over union,MIoU)上提升了14.32%,在戴斯相似系数(Dice similarity coefficient,DSC)上提升了13.18%,取得了较好的结果。该研究为计算机技术辅助医生进行皮肤病诊断提供了借鉴。展开更多
In the case of massive data,matrix operations are very computationally intensive,and the memory limitation in standalone mode leads to the system inefficiencies.At the same time,it is difficult for matrix operations t...In the case of massive data,matrix operations are very computationally intensive,and the memory limitation in standalone mode leads to the system inefficiencies.At the same time,it is difficult for matrix operations to achieve flexible switching between different requirements when implemented in hardware.To address this problem,this paper proposes a matrix operation accelerator based on reconfigurable arrays in the context of the application of recommender systems(RS).Based on the reconfigurable array processor(APR-16)with reconfiguration,a parallelized design of matrix operations on processing element(PE)array is realized with flexibility.The experimental results show that,compared with the proposed central processing unit(CPU)and graphics processing unit(GPU)hybrid implementation matrix multiplication framework,the energy efficiency ratio of the accelerator proposed in this paper is improved by about 35×.Compared with blocked alternating least squares(BALS),its the energy efficiency ratio has been accelerated by about 1×,and the switching of matrix factorization(MF)schemes suitable for different sparsity can be realized.展开更多
基金supported in part by the National Key Research and Development Program of China under Grant 2019YFB1803400in part by the National Science Foundation of China under Grant 62001179in part by the Fundamental Research Funds for the Central Universities under Grant 2020kfyXJJS111.
文摘In this paper,average bit error probability(ABEP)bound of optimal maximum likelihood(ML)detector is first derived for ultra massive(UM)multiple-input-multiple-output(MIMO)system with generalized amplitude phase modulation(APM),which is confirmed by simulation results.Furthermore,a minimum residual criterion(MRC)based lowcomplexity near-optimal ML detector is proposed for UM-MIMO system.Specifically,we first obtain an initial estimated signal by a conventional detector,i.e.,matched filter(MF),or minimum mean square error(MMSE)and so on.Furthermore,MRC based error correction mechanism(ECM)is proposed to correct the erroneous symbol encountered in the initial result.Simulation results are shown that the performance of the proposed MRC-ECM based detector is capable of approaching theoretical ABEP of ML,despite only imposing a slightly higher complexity than that of the initial detector.
文摘In market economy,SNA(A System of National Accounts),GFS(A System of Government Finance Statistics)and MFS(Money Finance Summery)are the important tools in management of macro-economy In this paper,a comparison of SNA,GFS and MFS were made on the accounting rule,the accounting structure and the accounting general framework,and a analysis were made on the accounting body,the accounting objective,the system of indicators,the standard classification and the full accounts.
文摘文章提出了一种新的基于MFS法(Method of Fundamental Solutions,即基本解法)的求解船舶势流问题的无网格数值方法。该方法采用势流控制方程的基本解表达流场中的速度势,可以得到任意阶连续的速度势导数;另外,通过引入流场虚边界的概念避免了传统边界元方法中存在奇点的问题。相比传统的边界元方法,MFS法具有无奇性、不依赖网格、不涉及数值积分、数学原理简单和算法易于编程实现的优势。文中对于MFS法在求解浅水二维剖面水动力系数中的应用进行了探索,提出了一套实用的数值算法,并进一步结合频域切片法计算了Wigley船体的垂荡和纵摇响应,通过和频域面元法及试验结果的对比验证了方法的正确性和实用性;最后应用开发的程序分析了不同水深和航速对于耐波性的影响。该研究开创性地将MFS方法应用到了船舶水动力研究领域,为之后更深入广泛地应用这一特性优良的数值方法提供了有益的参考。
文摘针对现有皮肤镜图像分割技术分割精度不高的问题,提出了一种基于多尺度信息提取和特征融合的U型网络(multi-scale information extraction and feature fusion U-shaped network,MF-UNet)模型。在U-Net的基础上,在卷积层后加入批归一化层,将原本的跳跃连接部分替换为4级特征融合模块,充分利用语义信息和位置信息,在特征提取端末尾加入多尺度空洞卷积模块和多尺度池化模块,增大感受野,利用双路拼接上采样模块进行上采样,减少图像恢复过程中的信息损失。实验表明,相较于U-Net模型,MF-UNet在平均交并比(mean intersection over union,MIoU)上提升了14.32%,在戴斯相似系数(Dice similarity coefficient,DSC)上提升了13.18%,取得了较好的结果。该研究为计算机技术辅助医生进行皮肤病诊断提供了借鉴。
基金the National Key R&D Program of China(No.2022ZD0119001)the National Natural Science Foundation of China(No.61834005)+3 种基金the Shaanxi Province Key R&D Plan(No.2022GY-027)the Key Scientific Research Project of Shaanxi Department of Education(No.22JY060)the Education Research Project of Xi'an University of Posts and Telecommunications(No.JGA202108)the Graduate Student Innovation Fund of Xi’an University of Posts and Telecommunications(No.CXJJYL2022035).
文摘In the case of massive data,matrix operations are very computationally intensive,and the memory limitation in standalone mode leads to the system inefficiencies.At the same time,it is difficult for matrix operations to achieve flexible switching between different requirements when implemented in hardware.To address this problem,this paper proposes a matrix operation accelerator based on reconfigurable arrays in the context of the application of recommender systems(RS).Based on the reconfigurable array processor(APR-16)with reconfiguration,a parallelized design of matrix operations on processing element(PE)array is realized with flexibility.The experimental results show that,compared with the proposed central processing unit(CPU)and graphics processing unit(GPU)hybrid implementation matrix multiplication framework,the energy efficiency ratio of the accelerator proposed in this paper is improved by about 35×.Compared with blocked alternating least squares(BALS),its the energy efficiency ratio has been accelerated by about 1×,and the switching of matrix factorization(MF)schemes suitable for different sparsity can be realized.