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Minimum Data Set for Assessing Soil Quality in Farmland of Northeast China

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Pedosphere 2013年第5期23卷 564-576页

作者： chen yu-dong WANG Huo-Yan ZHOU Jian-Min XING Lu ZHU Bai-Shu ZHAO Yong-Cun chen Xiao-Qin Institute of Soil Science Chinese Academy of Science University of Chinese Academy of Sciences Southwest University College of Resources and Environment

Soil quality assessment provides a tool for agriculture managers and policy makers to gain a better understanding of how various agricultural systems affect soil resources. Soil quality of Hailun County, a typical soybean （Glycine max L. Merill） growing area located in Northeast China, was evaluated using soil quality index （SQI） methods. Each SQI was computed using a minimum data set （MDS） selected using principal components analysis （PCA） as a data reduction technique. Eight MDS indicators were selected from 20 physical and chemical soil measurements. The MDS accounted for 74.9% of the total variance in the total data set （TDS）. The SQI values for 88 soil samples were evaluated with linear scoring techniques and various weight methods. The results showed that SQI values correlated well with soybean yield （r = 0.658＊＊） when indicators in MDS were weighted by the regression coefficient computed for each yield and index. Stepwise regression between yield and principal components （PCs） indicated that available boron （AvB）, available phosphorus （AvP）, available potassium （AvK）, available iron （AvFe） and texture were the main factors limiting soybean yield. The method used to select an MDS could not only appropriately assess soil quality but also be used as a powerful tool for soil nutrient diagnosis at the regional level.

关键词： norm value principal component analysis soil quality index stepwise regression

Developing time-of-flight polarized neutron capability at the China Spallation Neutron Source

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Nuclear Science and Techniques 2023年第10期34卷 12-19页

作者： Long Tian Ahmed Salman Chu-Yi Huang yu-chen dong Fan Ye Ze-Cong Qin Wolfgang Kreuzpaintner Jun-Pei Zhang Tian-Hao Wang Xin Tong Institute of High Energy Physics Chinese Academy of ScienceBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803China School of Nuclear Science and Technology University of the Chinese Academy of SciencesBeijing 100049China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

Polarized neutrons play an indispensable role in neutron scattering research and have been incorporated into various neutron diffractometers and spectrometers. Recognizing the importance of polarized neutrons, the China Spallation Neutron Source(CSNS) has dedicated resources for developing its own capabilities for polarized neutron techniques. Hence, a polarized neutron development platform was allocated to the BL-20 beam port at CSNS for the purpose of facilitating new technological developments and calibration of instruments. Here, we report the progress we have made in terms of using the established development platform at BL-20, including the characterization of neutron spin filter cells manufactured at CSNS, the calibration of self-developed polarized neutron instruments, performance of the polarized neutron technique applied to beamlines,and associated simulation work for beamline magnetic field environments. These results demonstrate the capability of the CSNS to develop time-of-flight polarized neutron instruments and techniques in-house, which will be incorporated into the construction of CSNS neutron beamlines.

关键词： Polarized neutron Polarization analysis Neutron instrumentation

Poly （ADP-ribose） polymerase inhibitor reduces heart ischaemia/ reperfusion injury via inflammation and Akt signalling in rats

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Chinese Medical Journal 2013年第10期126卷 1913-1917页

作者： SONG Zhao-feng chen dong-yu DU Bo JI Xiao-ping Department of CardiologyTaian Central Hospitall Taian Shandong271000 China Department ofRheumatologyTaian Central Hospitall Taian Shandong271000 China Department of Cardiology Shandong University Qilu Hospital JinanShandong 250012 China

Background Poly （ADP-ribose） polymerase （PARP） has been proposed to play an important role in the pathogenesis of heart ischaemia/reperfusion （I/R） injury. 3,4-dihydro-5-[4-（1-piperidinyl）butoxy]-l（2H）-isoquinolinone （DPQ）, a potent PARP inhibitor, has cardiac protective effects. Because the underlying mechanisms are not understood, we investigated the effect of DPQ on heart I/R injury and its mechanisms. Methods Studies were performed with I/R rats＇ hearts. DPQ was used to inhibit the activation of PARP. Cardiac function and cellular apoptosis were assessed. The activation of PARP, transcription factor nuclear factor-kappaB （NF-KB）, intercellular adhesion molecule-1 （ICAM-1）, cyclooxygenase-2 （COX-2） and matrix metalloproteinase-9 （MMP-9） were evaluated. We also evaluated expression of Akt and two of its downstream targets, glycogen synthase kinase-313 （GSK- 3β） and forkhead transcription factor FOXO3a. Results Administration of DPQ significantly decreased the activation of PARP and cellular apoptosis from （35±5）% to （20±4）% and simultaneously improved the cardiac function. DPQ reduced the expressions of NF-KB, ICAM-1, COX-2 and MMP-9 in rat heart and facilitated the activations of phosphor-Akt, phosphor-GSK-3β and phosphor-FOXO3a. Conclusion The protective effects of DPQ were associated with the suppression of inflammation and the activation of the Akt signalling pathways suggesting that the inhibition of poly （ADP-ribose） polymerase reduced heart I/R injury in rats.

关键词： heart ischaemia/reperfusion, poly (ADP-ribose) polymerase,3,4-dihydro-5-[4-(1-piperidinyl)butoxy]-l (2H)- isoquinolinone Akt," inflammation

亏损系统模态控制设计及其在机翼颤振控制中的应用

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吉林大学学报（工学版） 2006年第B03期36卷 4-7页

作者：陈宇东吉林大学机械科学与工程学院长春130022

讨论了亏损系统模态控制的设计方法,并将其应用在飞机机翼颤振的控制问题中。结果表明:在一定条件下,机翼的动态特性具有亏损性质,并且亏损模态可能是不可控制的,单输入控制不能稳定不可控制模态。为了稳定不可控制模态必须引入多输入... 详细信息

讨论了亏损系统模态控制的设计方法,并将其应用在飞机机翼颤振的控制问题中。结果表明:在一定条件下,机翼的动态特性具有亏损性质,并且亏损模态可能是不可控制的,单输入控制不能稳定不可控制模态。为了稳定不可控制模态必须引入多输入控制。

关键词：工程力学亏损系统模态控制设计飞机机翼的颤振控制

Robust color image hiding method in DCT domain

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Optoelectronics Letters 2006年第3期2卷 217-220页

作者： LI Qing-zhong yu chen CHU dong-sheng Engineering College Ocean University of China Qingdao 266071

This paper presents a robust color image hiding method based on YCbCr color system in discrete cosine transform （DOT） domain,which can hide a secret color image behind a public color cover image and is compatible with the international image compression standard of JPEG. To overcome the grave distortion problem in the restored secret image,this paper proposes a new embedding scheme consisting of reasonable partition of a pixel value and sign embedding. Moreover, based on human visual system （HVS） and fuzzy theory,this paper also presents a fuzzy classification method for DOT sub-blocks to realize the adaptive selection of embedding strength. The experimental results show that the maximum distortion error in pixel value for the extracted secret image is ±1. And the color cover image can provide good quality after embedding large amount of data.

关键词： DCT 域值图象隐藏鲁棒性离散分析

Identification of CNS neural circuitry involved in the innervation of C7 spinal nerve： a viral transsynaptic tracing study

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Chinese Journal of Traumatology 2011年第5期14卷 259-263页

作者： WEI Hai-feng chen Liang GU yu-dong Department of Orthopaedic Surgery Shanghai Sixth People＇s Hospital Shanghai Jiaotong University Shanghai 200233 China

Objective： Contralateral C7 spinal nerve transfer is a useful operation for the treatment of brachial plexus root avulsion. The recovery of the independent function at the ipsilateral side, however, depends on neural circuitry reorganization in the central nervous system （CNS）.This study tried to locate the CNS neuronal elements involved in the innervation ofC7 spinal ***： Pseudorabies virus （PRV, TK/gG-,2 μl）, which expressed green fluorescent protein （GFP）, was injected into the left C7 spinal nerve in 20 adult Sprague Dawley *** rats survived for 6 h, 12 h, 24 h and 36 h, the C1-C7segments of the spinal cord and brain were processed using a polyclonal immunohistochemical antibody against ***： PRV-labeled neurons were found mainly in gray matter of the C1-C7 segments of the spinal cord and at the following structures of the brain： lateral vestibular nucleus, lateral paragigantocellular nucleus, A5 cells, red nucleus, primary and secondary motor cortexes, primary and secondary somatosensory cortexes. Although located bilaterally, the PRV-labeled neurons existed predominantly in the ipsilateral side of the spinal cord and the contralateral side of the brain at 6-12 h after injection （p.i.）. The number of PRV-labeled neurons in the CNS was increasing with rat＇s survival time and the distribution of these neurons turned bilateral with no obvious dominance to either side at 24 h and 36 h （p.i.）.Conclusion： By use of transsynaptic tracing technique with PRV, the anatomically connected set of neurons,which modulates the activity of C7 spinal nerve, is located successfully in the CNS.

关键词： Brachial plexus Innervation Spinal nerves Central nervous system

不确定参数闭环振动控制系统的稳定性与鲁棒性区间分析

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吉林大学学报（工学版） 2006年第1期36卷 5-9页

作者：宋敏陈宇东陈塑寰吉林大学机械科学与工程学院

为了解决控制系统的不确定性问题,将不确定参数用区间表示,使不确定问题转化为确定性问题。提出了用系统物理参数构造区间状态矩阵的方法。用极点配置方法得到确定参数的状态反馈增益矩阵,然后用到实际不确定系统中。应用矩阵摄动和区... 详细信息

为了解决控制系统的不确定性问题,将不确定参数用区间表示,使不确定问题转化为确定性问题。提出了用系统物理参数构造区间状态矩阵的方法。用极点配置方法得到确定参数的状态反馈增益矩阵,然后用到实际不确定系统中。应用矩阵摄动和区间扩张,提出了估计特征值上下界的计算方法。数值算例表明:利用本文的计算结果可以估计系统不确定参数对闭环系统特征值实部和虚部的影响。

关键词：工程力学不确定系统振动控制闭环系统特征值稳定的鲁棒性区间分析

不确定参数结构振动控制系统响应的鲁棒性分析

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吉林大学学报（工学版） 2006年第B03期36卷 38-41页

作者：宋敏陈宇东陈塑寰吉林建筑工程学院土木工程系长春130021 吉林大学机械科学与工程学院长春130022

讨论了不确定参数的振动控制系统响应的鲁棒性问题,将不确定控制问题用确定性问题来近似,然后用到实际不确定系统中。应用矩阵摄动和区间扩张理论,提出了估计响应上下界的计算方法,并用一个数值算例说明了该方法的有效性。

关键词：工程力学不确定系统振动控制闭环系统特征值稳定的鲁棒性区间分析

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PON突发式长发光ONU的防护与检测

光通信研究 2017年第1期1期(24)卷 23-26页

作者：余辰东中兴通讯股份有限公司上海研发中心上海201203

PON(无源光网络)中突发式长发光干扰是异常上行光信号干扰的一种,由于其故障发生的随机性以及持续时间的瞬间性,使得故障难以定位。文章针对PON ONU(光网络单元)突发干扰问题,描述了突发长发光的几种表现与可能原因,总结了典型的防护方... 详细信息

PON(无源光网络)中突发式长发光干扰是异常上行光信号干扰的一种,由于其故障发生的随机性以及持续时间的瞬间性,使得故障难以定位。文章针对PON ONU(光网络单元)突发干扰问题,描述了突发长发光的几种表现与可能原因,总结了典型的防护方法,并对比了几种方法的优缺点;对定位故障ONU的方法进行了探讨,给出了彻底消除故障的方法。

关键词：无源光网络光网络单元干扰突发式长发光