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Inhibitory gamma-aminobutyric acidergic neurons in the anterior cingulate cortex participate in the comorbidity of pain and emotion

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Neural Regeneration Research 2025年第10期20卷 2838-2854页

作者： Lu Guan Mengting Qiu na Li Zhengxiang Zhou Ru Ye Liyan Zhong Yashuang xu Junhui Ren Yi Liang Xiaomei Shao Jianqiao Fang Junfan Fang Junying du Department of Neurobiology and Acupuncture Research Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Key Laboratory for Research of Acupuncture Treatment and Transformation of Emotional Diseases Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Fuchun Community Health Service Center of Fuyang District HangzhouZhejiang ProvinceChina

Pain is often comorbid with emotional disorders such as anxiety and *** of the anterior cingulate cortex has been implicated in pain and pain-related negative emotions that arise from impairments in inhibitory gamma-aminobutyric acid *** review primarily aims to outline the main circuitry(including the input and output connectivity)of the anterior cingulate cortex and classification and functions of different gamma-aminobutyric acidergic neurons;it also describes the neurotransmitters/neuromodulators affecting these neurons,their intercommunication with other neurons,and their importance in mental comorbidities associated with chronic pain *** understanding on their role in pain-related mental comorbidities may facilitate the development of more effective treatments for these ***,the mechanisms that regulate gamma-aminobutyric acidergic systems remain *** is also unclear as to whether the mechanisms are presynaptic or *** exploration of the complexities of this system may reveal new pathways for research and drug development.

关键词： anterior cingulate cortex anxiety chronic pain circuit communication comorbidity depression gamma-aminobutyric acidergic neurons parvalbumin neurons synaptic transmission

Blind CFO estimation algorithm for OFDM systems by using generalized precoding and trilinear model

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Journal of Systems Engineering and Electronics 2012年第1期23卷 10-15页

作者： Xiaofei Zhang dazhuan xu Electronic Engineering Department Nanjing University of Aeronautics and Astronautics Nanjing 210016 R R. China

This paper discusses the blind carrier frequency offset （CFO） estimation for orthogonal frequency division multiplexing （OFDM） systems by utilizing trilinear decomposition and genera- lized preceding. Firstly, the generalized precoding is employed to obtain multiple covariance matrices which are requisite for the trilinear model, and then a novel CFO estimation algorithm is proposed for the OFDM system. Compared with both the joint diagonalizer and estimation of signal parameters via rotational invariant technique （ESPRIT）, the proposed algorithm enjoys a better CFO estimation performance. Furthermore, the proposed algorithm can work well without virtual carriers. Simulation results illustrate the performance of this algorithm,

关键词： carrier frequency offset (CFO) orthogonal frequency division multiplexing (OFDM) generalized precoding trilinear model.

Blind channel estimation for multiple antenna OFDM system subject to unknown carrier frequency offset

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Journal of Systems Engineering and Electronics 2014年第5期25卷 721-727页

作者： Xiaofei Zhang dazhuan xu Department of Electronic Engineering Nanjing University of Aeronautics and Astronautics

The problem of channel estimation for multiple an- tenna orthogonal frequency division multiplexing （OFDM） systems subject to unknown carrier frequency offset （CFO） is addressed. Multiple signal classification （MUSIC）-Iike algorithm, which generally has been used for direction estimation or frequency estimation, is used for channel estimation in multiple antenna OFDM systems. A reduced dimensional （RD）-MUSIC based algorithm for channel estimation is proposed in multiple antenna OFDM systems with unknown CFO. The Cramer-Rao bound （CRB） of channel estimation in multiple antenna OFDM systems with unknown CFO is derived. The proposed algorithm has a superior performance of channel estimation compared with the Capon method and the least squares method.

关键词： channel estimation orthogonal frequency division multiplexing (OFDM) multiple antennas multiple signal classification (MUSIC).

Angle estimation in bistatic MIMO radar using improved reduced dimension Capon algorithm

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Journal of Systems Engineering and Electronics 2013年第1期24卷 84-89页

作者： Xiaofei Zhang dazhuan xu Electronic Engineering Department Nanjing University of Aeronautics and Astronautics

This paper discusses the problem of direction of departure （DOD） and direction of arrival （DOA） estimation for a bistatic multiple input multiple output （MIMO） radar, and proposes an improved reduced-dimension Capon algorithm therein. Compared with the reduced-dimension Capon algorithm which requires pair matching between the two-dimensional angle estimation, the pro- posed algorithm can obtain automatically paired DOD and DOA estimation without debasing the performance of angle estimation in bistatic MIMO radar. Furthermore, the proposed algorithm has a lower complexity than the reduced-dimension Capon algorithm, and it is suitable for non-uniform linear arrays. The complexity of the proposed algorithm is analyzed and the Cramer-Rao bound （CRB） is also derived. Simulation results verify the usefulness of the proposed algorithm.

关键词： multiple input multiple output (MIMO) radar angle estimation Capon algorithm non-uniform array.

Two Classes of Quaternary Codes from Z_4-valued Quadratic Forms

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Transactions of nanjing University of Aeronautics and Astronautics 2018年第5期35卷 896-912页

作者： Zhu Xiaoxing xu dazhuan College of Mathematics Nanjing University of Aeronautics and Astronautics College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics

Let R=GR (4,m)be a Galois ring with Teichmuller set T_m and Tr_m be the trace function fromRto Z_*** this paper,two classes of quaternary codes C_1 = {c(a,b):a ∈R,b ∈ T_(m/2)},where c(a,b)=(Tr_m(ax)+Tr_(m/2)(2 bx^(2 m/2 +1)))_(x∈T_m),and C_2= {c(a,b):a ∈ R,b ∈ T_m}, where c(a,b)=(Tr_m(ax+2 bx^(2 k+1)))_(x∈T_m),and m/gcd(m,k)is even,are investigated,*** Lee weight distributions,Hamming weight distributions and complete weight distributions of the codes are completely given.

关键词： Galois ring quaternary code Hamming weight quadratic form Lee weight

基于粒子群优化算法的农业机器人控制策略研究

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农机化研究 2025年第1期47卷 205-209页

作者：王娜吴延凯许娜河南工业职业技术学院河南南阳473000

介绍了粒子群优化算法的概念,并由数学模型、边界约束和环境约束对农业机器人优化约束模型进行了分析,实现了对农业机器人的动态避障和路径规划。仿真实验表明:针对复杂的作业环境,农业机器人可以进行最优避障路径规划,且算法收敛速度较... 详细信息

介绍了粒子群优化算法的概念,并由数学模型、边界约束和环境约束对农业机器人优化约束模型进行了分析,实现了对农业机器人的动态避障和路径规划。仿真实验表明:针对复杂的作业环境,农业机器人可以进行最优避障路径规划,且算法收敛速度较快,能够满足设计要求,证明系统具有一定的可行性。

关键词：农业机器人粒子群优化约束模型避障路径规划

维普期刊数据库博看期刊

Linear Codes with Two Weights or Three Weights from Two Types of Quadratic forms

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Transactions of nanjing University of Aeronautics and Astronautics 2017年第1期34卷 62-71页

作者： Zhu Xiaoxing xu dazhuan Department of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China

Let F_qbe afinite field with q=pmelements,where pis an odd prime and mis apositive ***,let D_0={(x_1,x_2)∈F_q^2\{(0,0)}:Tr(x_1^(pk1+1)+x_2^(pk2+1))=c},where c∈F_q,Tr is the trace function fromFF_qtoFpand m/(m,k_1)is odd,m/(m,k_2)is *** ap-ary linear code C_D =c(a_1,a_2):(a_1,a_2)∈F_q^2},where c(a_1,a_2)=(Tr(a_1x_1+a_2x_2))_((x1,x2)∈D).At most three-weight distributions of two classes of linear codes are settled.

关键词： linear codes weight distribution Gauss sum Weil sum

The design and analysis of unequal error protection fountain coding for multiple source networks over binary erasure channels

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Science China(Information Sciences) 2014年第8期57卷 9-17页

作者： SHAO HanQin xu dazhuan ZHANG XiaoFei College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics

A novel network model of multiple source fountain coding is developed and a novel class of generic multiple source fountain codes with unequal error protection(UEP)property is *** And–Or tree analysis technique is generalized to analyze the asymptotic performance of the proposed codes and a joint optimization method employing both linear and nonlinear programs is developed to optimize the degree ***,we propose three basic methods to achieve UEP property and the performance of each method is *** employ these analytical results and optimization method to design and discuss several UEP codes with two and four sources for different application *** results verify that the proposed codes can be applied to the networks with any number of sources and can provide strong UEP property in various ways based on the proposed three basic methods.

关键词： asymptotic analysis fountain codes binary erasure channels network coding linear program nonlinear program unequal error protection multiple source networks

A simplified bit metric calculation method for high-order PSK

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Science China(Information Sciences) 2013年第7期56卷 109-117页

作者： WANG Lei xu dazhuan ZHANG XiaoFei College of Information Science and Technology Nanjing University of Aeronautics and Astronautics

This paper proposes a simplified bit metric calculation method for high-order PSK signal with Gray-mapping. This method calculates the bit metric recursively by the symmetry of Gray code. Analysis and simulation results show that the proposed method can significantly reduce the computational complexity and maintain similar performance compared to ML and Max-Log bit metric. Additionally, this method generates bit metrics of PSK signals with different modulation order in the same way, so it can be applied to adaptive modulation system.

关键词： phase shift keying high order modulation bit metric soft demodulation