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Climate Sensitivity and Feedbacks of a New Coupled Model CAMS-CSM to Idealized CO2 Forcing: A Comparison with CMIP5 Models
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作者 Xiaolong CHEN Zhun GUO +5 位作者 Tianjun ZHOU Jian LI Xinyao RONG Yufei XIN Haoming CHEN Jingzhi SU 《气象学报:英文版》 SCIE CSCD 2019年第1期31-45,共15页
Climate sensitivity and feedbacks are basic and important metrics to a climate system. They determine how large surface air temperature will increase under CO2 forcing ultimately, which is essential for carbon reducti... Climate sensitivity and feedbacks are basic and important metrics to a climate system. They determine how large surface air temperature will increase under CO2 forcing ultimately, which is essential for carbon reduction policies to achieve a specific warming target. In this study, these metrics are analyzed in a climate system model newly developed by the Chinese Academy of Meteorological Sciences(CAMS-CSM) and compared with multi-model results from the Coupled Model Comparison Project phase 5(CMIP5). Based on two idealized CO2 forcing scenarios, i.e.,abruptly quadrupled CO2 and CO2 increasing 1% per year, the equilibrium climate sensitivity(ECS) and transient climate response(TCR) in CAMS-CSM are estimated to be about 2.27 and 1.88 K, respectively. The ECS is near the lower bound of CMIP5 models whereas the TCR is closer to the multi-model ensemble mean(MME) of CMIP5 due to compensation of a relatively low ocean heat uptake(OHU) efficiency. The low ECS is caused by an unusually negative climate feedback in CAMS-CSM, which is attributed to cloud shortwave feedback(λSWCL) over the tropical Indo-Pacific Ocean.The CMIP5 ensemble shows that more negative λSWCL is related to larger increase in low-level(925–700 hPa)cloud over the tropical Indo-Pacific under warming, which can explain about 90% of λSWCL in CAMS-CSM. Static stability of planetary boundary layer in the pre-industrial simulation is a critical factor controlling the low-cloud response and λSWCL across the CMIP5 models and CAMS-CSM. Evidently, weak stability in CAMS-CSM favors lowcloud formation under warming due to increased low-level convergence and relative humidity, with the help of enhanced evaporation from the warming tropical Pacific. Consequently, cloud liquid water increases, amplifying cloud albedo, and eventually contributing to the unusually negative λSWCL and low ECS in CAMS-CSM. Moreover, the OHU may influence climate feedbacks and then the ECS by modulating regional sea surface temperature responses. 展开更多
关键词 CLIMATE sensitivity CLIMATE FEEDBACK cloud shortwave FEEDBACK the Chinese Academy of Meteorological Sciences CLIMATE system model(CAMS-CSM) Coupled MODEL COMPARISON Project phase 5(CMIP5)
无线传感器网络时间同步技术进展 预览
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作者 张超 《重庆工商大学学报:自然科学版》 2019年第6期88-94,共7页
无线传感器网络是由大量部署在无线环境中的传感器设备构成的网络,无线节点间的协同操作要求网络节点维护共同的时间,时间同步是无线传感器网络支撑技术;针对传统分类方法中不能有效体现时间同步算法特点的问题,从信息交换是否存在反馈... 无线传感器网络是由大量部署在无线环境中的传感器设备构成的网络,无线节点间的协同操作要求网络节点维护共同的时间,时间同步是无线传感器网络支撑技术;针对传统分类方法中不能有效体现时间同步算法特点的问题,从信息交换是否存在反馈角度对现有时间同步算法进行了重新分类,同时对同步算法的进展情况作了详细描述;新的分类方法能够有效体现算法同步精度和同步能耗等特性:反馈式时间同步机制在同步精度和同步能耗上都要高于非反馈式时间同步机制;最后总结了现有时间同步算法的缺陷并展望了未来时间同步技术的发展方向。 展开更多
关键词 无线传感器网络 时间同步 技术进展 反馈式 非反馈式
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Adaptive Control of Congestion in Tough Wireless Environments Using DCM+ Algorithm 预览
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作者 Rushdi Hamamreh Derar Khader 《通讯、网络与系统学国际期刊(英文)》 2019年第8期113-123,共11页
The aim of this paper is to present DCM+, a new congestion control protocol for data networks. It stands for Dynamic Congestion control for Mobile networks. New metrics have been newly invented and introduced like nor... The aim of this paper is to present DCM+, a new congestion control protocol for data networks. It stands for Dynamic Congestion control for Mobile networks. New metrics have been newly invented and introduced like normalized advancing index (NAI) and complete transmission time (CTT). The simulations are done for a simple single-hop-topology (sender-router-receiver). The outcomes of this protocol are excellent and, in most cases, better than other approaches. The excellent properties of our proposed protocol were possible through tracking the available slow-start threshold. We achieved performance improvement, minimized end-to-end delay and large reduction in transmission time. DCM+ was able to combine many advantages at same time of the protocols NewReno and Westwood+. The results show, that DCM+ is extremely adequate for different types of networks. Feedback as main principle of control theory was used to control the congestion in the network. The parameters Round-Trip-Time (RTT) and Retransmission Timeout (RTO) are used as feedback signals to adjust the next congestion window (cwnd). 展开更多
关键词 CONGESTION Control Westwood+ Slow-Start CONGESTION AVOIDANCE Bandwidth Estimation Round-Trip Time RETRANSMISSION TIMEOUT Feedback ns-3
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Aperiodically intermittent stochastic stabilization via discrete time or delay feedback control
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作者 Lei LIU Matjaz PERC Jinde CAO 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第7期183-195,共13页
In this paper,we present stochastic intermittent stabilization based on the feedback of the discrete time or the delay time.By using the stochastic comparison principle,the Ito formula,and the BorelCantelli lemma,we o... In this paper,we present stochastic intermittent stabilization based on the feedback of the discrete time or the delay time.By using the stochastic comparison principle,the Ito formula,and the BorelCantelli lemma,we obtain two sufficient criteria for stochastic intermittent stabilization.The established criteria show that an unstable system can be stabilized by means of a stochastic intermittent noise via a discrete time feedback if the duration timeτis bounded byτ*.Similarly,stabilization via delay time feedback is equally possible if the lag timeτis bounded byτ**.The upper boundτ*andτ**can be computed numerically by solving corresponding equation. 展开更多
关键词 BROWNIAN motion stochastic STABILIZATION INTERMITTENT CONTROL DISCRETE time FEEDBACK timedelay FEEDBACK
Advances in narrow linewidth diode lasers
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作者 Xingkai LANG Peng JIA +7 位作者 Yongyi CHEN Li QIN Lei LIANG Chao CHEN Yubing WANG Xiaonan SHAN Yongqiang NING Lijun WANG 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第6期21-33,共13页
The smart travel era has come and requirement for high precision lidar detection technology is higher and higher. The new solid-state lidars can meet the requirements of intelligent cars in the future, with the advant... The smart travel era has come and requirement for high precision lidar detection technology is higher and higher. The new solid-state lidars can meet the requirements of intelligent cars in the future, with the advantages of high resolution, strong anti-active jamming ability, small volume, light weight, low cost and so on. The narrow linewidth diode laser is the perfect light source of solid-state lidars. The progress and development of narrow linewidth diode laser technique can greatly improve the application of solidstate lidar. The technology and development status of narrow linewidth diode lasers has been described detailly in the paper. And the design ideas, key fabrication technologies and optical characteristics of various narrow linewidth diode lasers have been analyzed and discussed as well. Finally, the developments of narrow linewidth diode lasers are prospected. 展开更多
关键词 diode lasers narrow LINEWIDTH internal CAVITY OPTICAL FEEDBACK TECHNOLOGY external CAVITY OPTICAL FEEDBACK TECHNOLOGY SOLID-STATE lidar
师徒反馈环境:多维度结构和潜剖面分析
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作者 巩振兴 李美莹 +1 位作者 王玮璇 张文彤 《中国人力资源开发》 CSSCI 北大核心 2019年第11期48-63,共16页
为了探索师徒反馈环境的内容结构,挖掘师徒反馈环境的潜在类别及其具体外在特征,本研究分别对635名和239名员工进行了调查研究。依次经过探索性因素分析和验证性因子分析,发现了师徒反馈环境的七维度结构:反馈源的可信性、反馈质量、反... 为了探索师徒反馈环境的内容结构,挖掘师徒反馈环境的潜在类别及其具体外在特征,本研究分别对635名和239名员工进行了调查研究。依次经过探索性因素分析和验证性因子分析,发现了师徒反馈环境的七维度结构:反馈源的可信性、反馈质量、反馈方式、积极反馈的准确性、消极反馈的准确性、反馈源的可利用性、支持反馈寻求。基于潜剖面分析将师徒反馈环境分为三个潜在类别,即"较好"、"中等"和"较差"的师徒反馈环境。其中,较好的反馈环境的特点为:反馈方式分值低而其他维度分值高。较差的反馈环境的特点为:反馈方式的分值相对较高而其他维度分值较低,这体现了师徒反馈环境中师徒双方对反馈方式的不敏感和对其他维度的高度关注。不同类别的师徒反馈环境对工作绩效、组织公民行为、工作满意度和创造力的影响存在显著差异,各项统计指标支持了师徒反馈环境分为三类的典型性。 展开更多
关键词 师徒 反馈 反馈环境 潜剖面分析
Efficient Network Dismantling via Node Explosive Percolation
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作者 秦绍萌 任晓龙 吕琳媛 《理论物理通讯:英文版》 SCIE CAS CSCD 2019年第6期764-772,共9页
The network dismantling problem asks the minimum separate node set of a graph whose removal will break the graph into connected components with the size not larger than the one percentage of the original graph.This pr... The network dismantling problem asks the minimum separate node set of a graph whose removal will break the graph into connected components with the size not larger than the one percentage of the original graph.This problem has attracted much attention recently and a lot of algorithms have been proposed. However, most of the network dismantling algorithms mainly focus on which nodes are included in the minimum separate set but overlook how to order them for removal, which will lead to low general efficiency during the dismantling process. In this paper,we reformulate the network dismantling problem by taking the order of nodes’ removal into consideration. An efficient dismantling sequence will break the network quickly during the dismantling processes. We take the belief-propagation guided decimation(BPD) dismantling algorithm, a state-of-the-art algorithm, as an example, and employ the node explosive percolation(NEP) algorithm to reorder the early part of the dismantling sequence given by the BPD. The proposed method is denoted as the NEP-BPD algorithm(NBA) here. The numerical results on Erd¨os-R′enyi graphs,random-regular graphs, scale-free graphs, and some real networks show the high general efficiency of NBA during the entire dismantling process. In addition, numerical computations on random graph ensembles with the size from 210 to219 exhibit that the NBA is in the same complexity class with the BPD algorithm. It is clear that the NEP method we used to improve the general efficiency could also be applied to other dismantling algorithms, such as Min-Sum algorithm,equal graph partitioning algorithm and so on. 展开更多
关键词 NETWORK DISMANTLING EXPLOSIVE PERCOLATION NETWORK ROBUSTNESS feedback VERTEX set
应用镜像神经元理论的视觉反馈训练对脑卒中早期偏瘫患者肢体功能及日常生活活动能力的影响
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作者 王海华 江云芬 《中国基层医药》 CAS 2019年第16期1995-1998,共4页
目的探讨应用镜像神经元理论的视觉反馈训练应用于脑卒中早期偏瘫患者中的效果。方法选取温岭市第一人民医院2014年7月至2017年7月收治的脑卒中早期偏瘫患者122例作为研究对象,待患者病情稳定后均行基于镜像神经元理论的视觉反馈训练。... 目的探讨应用镜像神经元理论的视觉反馈训练应用于脑卒中早期偏瘫患者中的效果。方法选取温岭市第一人民医院2014年7月至2017年7月收治的脑卒中早期偏瘫患者122例作为研究对象,待患者病情稳定后均行基于镜像神经元理论的视觉反馈训练。采用简式Fugl-Meyer运动功能评定量评价患者治疗前后上肢功能状况;采用改良Ashworth量表评价患者治疗前后上肢肌张力状况。采用Barthel指数评价患者治疗前后日常生活活动能力。结果患者治疗后FMA评分为(35.74±11.24)分,明显高于治疗前的(28.81±9.68)分(t=5.160,P=0.000);治疗后BI评分为(76.24±14.77)分,明显高于治疗前的(52.93±12.28)分(t=13.404,P=0.000)。治疗后患者屈肘肌群肌张力分级为(1.57±0.76)级,明显低于治疗前的(3.24±0.72)级(t=17.619,P=0.000);前臂旋前肌群肌张力分级为(2.14±0.96)级,明显低于治疗前的(3.28±0.75)级(t=10.336,P=0.000)。结论基于镜像神经元理论的视觉反馈训练可有助于改善脑卒中早期偏瘫患者上肢功能,减轻痉挛症状,更好的提高患者日常生活活动能力,对促进其康复具有积极作用。 展开更多
关键词 脑血管障碍 反馈 心理学 镜神经元 早期偏瘫 上肢功能 日常生活活动能力
Quantum discord of two-qutrit system under quantum-jump-based feedback control
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作者 王畅 方卯发 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第12期75-81,共7页
This paper studies quantum discord of two qutrits coupled to their own environments independently and coupled to the same environment simultaneously under quantum-jump-based feedback control. Our results show that spo... This paper studies quantum discord of two qutrits coupled to their own environments independently and coupled to the same environment simultaneously under quantum-jump-based feedback control. Our results show that spontaneous emission, quantum feedback parameters, classical driving, initial state, and detection efficiency all affect the evolution of quantum discord in a two-qutrit system. We find that under the condition of designing proper quantum-jump-based feedback parameters, quantum discord can be protected and prepared. In the case where two qutrits are independently coupled to their own environments, classical driving, spontaneous emission, and low detection efficiency have negative effect on the protection of quantum discord. For different initial states, it is found that the evolution of quantum discord under the control of appropriate parameters is similar. In the case where two qutrits are simultaneously coupled to the same environment,the classical driving plays a positive role in the generation of quantum discord, but spontaneous emission and low detection efficiency have negative impact on the generation of quantum discord. Most importantly, we find that the steady discord depends on feedback parameters, classical driving, and detection efficiency, but not on the initial state. 展开更多
关键词 QUTRIT quantum-jump-based feedback quantum discord
A 0.45-to-1.8 GHz synthesized injection-locked bang-bang phase locked loop with fine frequency tuning circuits
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作者 Jincheng YANG Zhao ZHANG +3 位作者 Nan QI Liyuan LIU Jian LIU Nanjian WU 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第6期106-121,共16页
This paper proposes a synthesized injection-locked bang-bang phased-locked loop(SILBBPLL)with high digital controlled oscillator(DCO) frequency resolution. The SILBBPLL is expressed with hardware description language ... This paper proposes a synthesized injection-locked bang-bang phased-locked loop(SILBBPLL)with high digital controlled oscillator(DCO) frequency resolution. The SILBBPLL is expressed with hardware description language and automatically placed & routed(APR) by using standard digital circuit design flow. As the mismatch issues of the circuits are not considered carefully during the APR design flow, the phase noise performance is severely deteriorated. We adopt pulse injection locking technique to improve the phase noise performance. The DCO frequency resolution is critical for reducing the reference spur in a digital injection-locked PLL. Therefore, we propose novel frequency tuning circuits to increase the DCO frequency resolution so that the reference spurs are reduced. The frequency tuning circuits consist of a standard cell based high-linearity output feedback DAC(OFDAC) and two custom varactors. The OFDAC is used to tune the frequency of the DCO with the custom varactor precisely. The custom varactor is firstly designed,added into the standard cell library, and APR with the standard cells. The SILBBPLL chip with a core area of 0.008 mm~2 is implemented in 65 nm CMOS process. When operating at 1.8 GHz, the measured results show that the root-mean-square(RMS) jitter integrated from 10 kH z to 100 MHz is 1.1 ps, and the power consumption is 1.5 mW with a 0.8-V supply. The proposed SILBBPLL achieves a figure-of-merit(FoM) of -237.4 dB and a reference spur of -50.9 dBc. 展开更多
关键词 SYNTHESIZED ALL-DIGITAL phased-locked loops(ADPLL) bang-bang phased-locked loop(BBPLL) AUTOMATICALLY placed & routed(APR) output feedback DAC(OFDAC) INJECTION-LOCKED
A slot microring sensor with feedback spiral waveguide for trace gas CH4 sensing in mid-infrared region
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作者 解凯鹤 张鑫 +2 位作者 张晓伟 金涵 简家文 《光电子快报:英文版》 EI 2019年第1期1-5,共5页
In this paper, a slot microring resonator with a piece of spiral feedback waveguide for CH4 sensing application is proposed. This sensor is based on silicon-on-insulator(SOI) substrate and with the operation wavelengt... In this paper, a slot microring resonator with a piece of spiral feedback waveguide for CH4 sensing application is proposed. This sensor is based on silicon-on-insulator(SOI) substrate and with the operation wavelength in mid-infrared region. To reach high sensitivity and good selectivity, slot cross section and spiral feedback waveguide are carefully tailored. The sensor shows ppb-scale trace gas sensing potential and is easy to be packaged in integrated photonics circuits. Calculation results show that the sensitivity reaches 1.4×10-2 dB/ppm and the detection limit achieves 700 ppb in the case of Lspiral=100 Lr. 展开更多
关键词 MICRORING FEEDBACK WAVELENGTH
1 kHz single-frequency, injection-seeded Er:YAG laser with an optical feedback
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作者 张艺轩 高春清 +4 位作者 王庆 纳全鑫 张濛 高明伟 黄帅 《中国光学快报:英文版》 SCIE EI CAS CSCD 2019年第3期50-54,共5页
A novel 1 kHz single-frequency, Q-switched Er-doped yttrium aluminum garnet(Er:YAG) laser pumped by a 1470 nm laser diode is demonstrated. The 500 ns, 5.52 mJ single-frequency, diffraction-limited pulses are obtained ... A novel 1 kHz single-frequency, Q-switched Er-doped yttrium aluminum garnet(Er:YAG) laser pumped by a 1470 nm laser diode is demonstrated. The 500 ns, 5.52 mJ single-frequency, diffraction-limited pulses are obtained by using a ‘ramp-fire’ injection-seeding technique and an optical feedback architecture. The full width at half-maximum of the pulse spectrum is measured to be 1.47 MHz by using the heterodyne technique. The beam quality M2 factors are measured to be 1.18 and 1.24 in the x and y directions, respectively. 展开更多
关键词 1 KHZ SINGLE-FREQUENCY injection-seeded ER:YAG LASER optical FEEDBACK
操作技能直接观察法在外科动物实验教学中的应用 预览
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作者 张心武 张焱 +4 位作者 孙云 翟宏军 孙晓力 段艳霞 张迪 《中国继续医学教育》 2019年第2期51-52,共2页
目的探讨操作技能直接观察法(DOPS)在外科动物实验教学中应用与评价。方法以西安交通大学第二附属医院2015级临床医学专业60名见习生作为研究对象,将其随机分为实验组和对照组。实验组在进行每项实验技能教学中均以DOPS表进行一次形成... 目的探讨操作技能直接观察法(DOPS)在外科动物实验教学中应用与评价。方法以西安交通大学第二附属医院2015级临床医学专业60名见习生作为研究对象,将其随机分为实验组和对照组。实验组在进行每项实验技能教学中均以DOPS表进行一次形成性评价。对照组按照传统教学方式进行教学。比较实验组和对照组期末OSCE考试总成绩的平均值及满意度。结果期末OSCE考试总成绩实验组为(90.23±7.26)分,优于对照组的(84.77±9.54)分,差异具有统计学意义(P<0.05)。教师对DOPS考核结果的满意度高于对照组,差异具有统计学意义(P<0.01);见习生对DOPS考核结果的满意度高于对照组,差异具有统计学意义(P<0.01)。结论DOPS可作为外科动物实验教学中有效的形成性评价方法,能够提高学生操作水平和职业素养,能够有效促使教师及时调整带教模式与方法,值得在外科动物实验教学中进行应用。 展开更多
关键词 形成性评价 DOPS 外科动物实验 本科见习 反馈 OSCE
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一种新的多址接入传输优化系统 预览
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《现代电子技术》 北大核心 2019年第23期1-5,共5页
传统通信中,单根天线只发射一路用户数据,这样造成了射频链路和相关硬件的浪费。为解决上述问题,提出一种改进的方法,即一根天线传输多路数据,并建立起接收端与发射端的反馈机制,使得发射端能实时调整发射信号之间的相关性,同时在接收... 传统通信中,单根天线只发射一路用户数据,这样造成了射频链路和相关硬件的浪费。为解决上述问题,提出一种改进的方法,即一根天线传输多路数据,并建立起接收端与发射端的反馈机制,使得发射端能实时调整发射信号之间的相关性,同时在接收端采用一种全新的混合检测方式来检测接收端的信号。仿真结果表明,此传输方案能在同等时频资源条件下接入更多的用户,起到了节省硬件资源、提升通信性能的作用,同时还能使整个系统的误码率得到进一步的降低,提高了频谱利用率。 展开更多
关键词 MIMO 多路复用 反馈 信号检测 多用户接入 仿真分析
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Dynamics of Quantum Fisher Information in Homodyne-Mediated Feedback Control
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作者 陈丽 严冬 +1 位作者 宋立军 张寿 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第3期14-18,共5页
We investigate the quantum Fisher information(QFI) dynamics of a dissipative two-level system in homodynemediated quantum feedback control. The analytical results demonstrate that the maximum values and stable values ... We investigate the quantum Fisher information(QFI) dynamics of a dissipative two-level system in homodynemediated quantum feedback control. The analytical results demonstrate that the maximum values and stable values of the QFI can be greatly enhanced via feedback control. The quantum feedback plays a more evident role in the improvement of classical Fisher information. The classical part can reach a high stable value, while the quantum part eventually decays to zero whatever the feedback parameter is. 展开更多
关键词 DYNAMICS FISHER Information FEEDBACK Control
镜像视觉反馈对脑梗死后单侧空间忽略患者的康复疗效 预览
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作者 杨美丽 吴振纲 +5 位作者 叶励超 陈雅芳 黄银辉 卓识途 何惠玲 王凌星 《中华老年心脑血管病杂志》 CAS 北大核心 2019年第1期45-48,共4页
目的探讨镜像视觉反馈对脑梗死后单侧空间忽略患者的康复疗效。方法选择脑梗死后单侧空间忽略患者42例,按照随机信封法隐藏分配方案分为对照组20例和镜像组22例。对照组采用常规治疗和康复,镜像组在常规治疗和康复基础上采用镜像视觉反... 目的探讨镜像视觉反馈对脑梗死后单侧空间忽略患者的康复疗效。方法选择脑梗死后单侧空间忽略患者42例,按照随机信封法隐藏分配方案分为对照组20例和镜像组22例。对照组采用常规治疗和康复,镜像组在常规治疗和康复基础上采用镜像视觉反馈治疗。对治疗前、治疗4周后进行评价,忽略程度采用凯瑟林-波哥量表(CBS)评分,平衡功能采用Berg平衡量表(BBS)评分,日常生活活动能力采用功能独立性评定法(FIM)评分。结果与治疗前比较,2组治疗后CBS评分明显降低,BBS和FIM评分明显升高,差异有统计学意义(P<0.05)。与对照组比较,镜像组治疗后CBS评分明显降低[(10.65±4.17)分vs(15.76±8.89)分,BBS和FIM评分明显升高(56.10±20.23)分vs(44.43±11.38)分,(74.69±17.71)分vs(57.82±12.11)分,P<0.05]。结论镜像视觉反馈对脑梗死后单侧空间忽略患者能显著改善平衡功能及生活自理能力,是临床便捷有效的康复治疗方法。 展开更多
关键词 脑梗死 功能偏侧化 视觉 反馈
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A GmNINa-miR172c-NNC1 Regulatory Network Coordinates the Nodulation and Autoregulation of Nodulation Pathways in Soybean
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作者 Lixiang Wang Zhengxi Sun +5 位作者 Chao Su Yongliang Wang Qiqi Yan Jiahuan Chen Thomas Ott Xia Li 《分子植物:英文版》 SCIE CAS CSCD 2019年第9期1211-1226,共16页
Symbiotic root nodules are root lateral organs of plants in which nitrogen-fixing bacteria(rhizobia)convert atmospheric nitrogen to ammonia.The formation and number of nodules in legumes are precisely controlled by a ... Symbiotic root nodules are root lateral organs of plants in which nitrogen-fixing bacteria(rhizobia)convert atmospheric nitrogen to ammonia.The formation and number of nodules in legumes are precisely controlled by a rhizobia-induced signal cascade and host-controlled autoregulation of nodulation(AON).However,how these pathways are integrated and their underlying mechanisms are unclear.Here,we report that microRNA172c(miR172c)activates soybean(Glycine max)R hizobia-induced CLE1(GmRICI)and GmRIC2 by removing the transcriptional repression of these genes by Nodule Number Control 1(NNC1),leading to the activation of the AON pathway.NNC1 interacts with GmNINa,the soybean ortholog of Lotus NODULE INCEPTION(NIN),and hampers its transcriptional activation o i G m RICI and GmRIC2.Importantly,GmNINa acts as a transcriptional activator of miR172c.Intriguingly,NNC1 can transcriptionally repress miR172c expression,adding a negative feedback loop into the NNC1 regulatory network.Moreover,GmNINa interacts with NNC1 and can relieve the NNC1-mediated repression of miR172c transcription.Thus,the GmNINa-miR172c-NNC1 network is a master switch that coordinately regulates and optimizes NF and AON signaling,supporting the balance between nodulation and AON in soybean. 展开更多
关键词 NODULE number AUTOREGULATION of NODULATION miR172c-NNC1 negative feedback loop NODULE INCEPTION
Exponential Stability of the Euler-Bernoulli Beam Equation with External Disturbance and Output Feedback Time-Delay
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作者 WU Jilong SHANG Yingfeng 《系统科学与复杂性学报:英文版》 SCIE EI CSCD 2019年第2期542-556,共15页
This paper concerns the stability of a one-dimensional Euler-Bernoulli beam equation with external disturbance and output feedback time-delay, in which the disturbance is bounded by an exponential function. In order t... This paper concerns the stability of a one-dimensional Euler-Bernoulli beam equation with external disturbance and output feedback time-delay, in which the disturbance is bounded by an exponential function. In order to estimate disturbance, the authors design an estimator of disturbance,which is composed of two parts: One is the system measurement that is called the eigen-measurement,another is a time-variant estimator of disturbance. Thus, the feedback controller which is based on the estimate of the disturbance is designed to stabilize the system. The finite-time stability of the system under this control law is proved by Lyapunov function method. Finally, some numerical simulations on the dynamical behavior of the closed-loop system is presented to show the correctness of the result. 展开更多
关键词 EIGENFUNCTION measurement EXPONENTIAL stability external DISTURBANCE feedback control
生物视觉诱发的轮廓检测方法研究
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作者 黄春燕 范影乐 +2 位作者 武薇 佘青山 甘海涛 《航天医学与医学工程》 CAS CSCD 北大核心 2019年第5期438-446,共9页
目的考虑到视觉机制与生物视觉感知高效性之间的密切联系,探究一种生物视觉诱发的轮廓检测新方法。方法首先提出一种经典感受野的视觉特征精细感知方法,以改善轮廓方位的检测精度;其次对前级最优朝向采取多尺度特征融合策略,以实现朝向... 目的考虑到视觉机制与生物视觉感知高效性之间的密切联系,探究一种生物视觉诱发的轮廓检测新方法。方法首先提出一种经典感受野的视觉特征精细感知方法,以改善轮廓方位的检测精度;其次对前级最优朝向采取多尺度特征融合策略,以实现朝向响应的多尺度优化;然后模拟一种非经典感受野响应的动态抑制机制,能够有效抑制响应中的纹理细节;最后提出一种视觉显著性信息的反馈融合模型,得到最终的轮廓响应。结果以RuG40图库为实验对象,基于人工标记轮廓图对检测结果进行客观评价,其中样本集和单样本的最优平均P指标分别为0.48和0.55,整体上优于GD、ISO以及MCI等主流方法;在BSD500数据集上的实验结果与RuG40图库结果基本一致。结论基于生物视觉诱发的图像处理方法,将为后续图像理解和分析提供一种新的思路。 展开更多
关键词 轮廓检测 方位层级细化 动态抑制 反馈
课堂评价中反馈对于促进学习的研究-以大学物理课堂教学为例 预览
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作者 段志刚 熊艳娇 彭智敏 《湖北开放职业学院学报》 2019年第20期147-148,共2页
为了改善目前教学体系中评价就是排名的现象,以反馈体系构建为核心手段,辨析了反馈概念在课堂评价中的演进过程,提出反馈就是学习信息与学习活动二重组合体的概念。通过学习目标制定、学习信息收集、反馈活动列表等三个阶段形成一次反... 为了改善目前教学体系中评价就是排名的现象,以反馈体系构建为核心手段,辨析了反馈概念在课堂评价中的演进过程,提出反馈就是学习信息与学习活动二重组合体的概念。通过学习目标制定、学习信息收集、反馈活动列表等三个阶段形成一次反馈学习循环来促进学习活动,并在大学物理教学中实践了该教学策略,用相应的评价指标证实了该策略的效果。该研究拓展了反馈促进学习的内涵,并对大学物理评价方式进行了新的探索。 展开更多
关键词 反馈 课堂评价 教学策略 大学物理
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