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CmMYB3-like negatively regulates anthocyanin biosynthesis and flower color formation during the post-flowering stage in Chrysanthemum morifolium
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作者 Lijie Zhou Shenhui Liu +6 位作者 Yiguang Wang Yuxi Wang Aiping Song Jiafu Jiang Sumei Chen Zhiyong Guan Fadi Chen 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期194-204,共11页
Color fading caused by a decrease in anthocyanin accumulation during the post-flowering stage significantly affects postharvest quality of chrysanthemum.However,the underlying mechanism by which anthocyanin accumulati... Color fading caused by a decrease in anthocyanin accumulation during the post-flowering stage significantly affects postharvest quality of chrysanthemum.However,the underlying mechanism by which anthocyanin accumulation decreases during the post-flowering stage still unclear,which greatly restricts design of molecular breeding in chrysanthemum.Here,a chrysanthemum SG7 R2R3 MYB transcription factor(TF),CmMYB3-like,was identified to have a function in regulating anthocyanin biosynthesis during the post-flowering stage.Quantitative real time PCR(qRT-PCR)assays showed that the expression of CmMYB3-like was gradually downregulated when anthocyanin content increased during the flowering stage and was significantly upregulated during the post-flowering stage.Genetic transformation of chrysanthemum and dual-luciferase assays in N.benthamiana leaves showed that CmMYB3-like suppressed anthocyanin accumulation by inhibiting the transcription of CmCHS and CmANS directly and that of CmF3H indirectly.However,overexpression or suppression of CmMYB3-like did not affect the biosynthesis of flavones or flavonols.Genetic transformation of chrysanthemum revealed that the overexpression of CmMYB3-like inhibited anthocyanin accumulation,but its suppression prevented the decrease in anthocyanin accumulation during the post-flowering stage.Our results revealed a crucial role of CmMYB3-like in regulating the color of petals during the post-flowering stage and provided a target gene for molecular design breeding to improve the postharvest quality of chrysanthemum. 展开更多
关键词 Post-flowering stage Color fading Anthocyanins CmMYB3-like CHRYSANTHEMUM Molecular breeding
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Effective Capacity of URLLC over Parallel Fading Channels with Imperfect Channel State Information
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作者 Peng Hongsen Tao Meixia 《China Communications》 SCIE CSCD 2024年第5期45-63,共19页
This paper investigates the effective capacity of a point-to-point ultra-reliable low latency communication(URLLC)transmission over multiple parallel sub-channels at finite blocklength(FBL)with imperfect channel state... This paper investigates the effective capacity of a point-to-point ultra-reliable low latency communication(URLLC)transmission over multiple parallel sub-channels at finite blocklength(FBL)with imperfect channel state information(CSI).Based on reasonable assumptions and approximations,we derive the effective capacity as a function of the pilot length,decoding error probability,transmit power and the sub-channel number.Then we reveal significant impact of the above parameters on the effective capacity.A closed-form lower bound of the effective capacity is derived and an alternating optimization based algorithm is proposed to find the optimal pilot length and decoding error probability.Simulation results validate our theoretical analysis and show that the closedform lower bound is very tight.In addition,through the simulations of the optimized effective capacity,insights for pilot length and decoding error probability optimization are provided to evaluate the optimal parameters in realistic systems. 展开更多
关键词 effective capacity finite blocklength regime imperfect CSI parallel fading channels URLLC
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Geological characterization and exploration potential of shale gas in the Carboniferous Jiusi Formation,northern Guizhou and Yunnan provinces,SW China
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作者 Weiming Feng Rong Li +3 位作者 Zhan Zhao Qian Yu Wei Liu Junfeng Cao 《Energy Geoscience》 2023年第3期169-181,共13页
Dark mudstones and shales of the Carboniferous Jiusi Formation are widely developed in northern Guizhou and Yunnan provinces, SW China. However, the distribution, reservoir characterization, and exploration potential ... Dark mudstones and shales of the Carboniferous Jiusi Formation are widely developed in northern Guizhou and Yunnan provinces, SW China. However, the distribution, reservoir characterization, and exploration potential of organic-rich shales in this area are yet to be quantified, thus limiting the prospect of shale gas in this area. This study investigates the basic geological conditions of Jiusi shale gas, using core data, well-logs, and some other test data, obtaining the following results. The organic-rich shales are mainly composed of deltaic-to-shallow-shelf deposits, with thickness ranging from 0 to 450 m, and above 350 m around the subsidence center. The organic matter is mainly type Ⅱ kerogen with TOC content of mostly 1%–2%, indicating a moderate maturity. The argillaceous shale reservoirs are indicative of strong heterogeneity, high clay minerals content, low porosity, low permeability, high specific surface area, and relatively developed secondary porosity. The gas-log anomaly intervals obtained from the survey wells have a cumulative thickness that is apparently greater than 200 m, and a few shale intervals showing high desorbed and adsorbed gas contents. Due to complex structures in the study area, conditions responsible for shale gas occurrence and trapping are generally moderate. However, areas having wide and gentle folds with moderate depth of burial reveals relatively favorable conditions of hydrocarbon traps. In contrast with typical marine-continental transitional shales, the Jiusi shale have better geological conditions for shale gas preservation. The analysis of the geological framework and hydrocarbon potential of Carboniferous Jiusi Formation provide more insight for the exploration of Carboniferous shale gas in southern China. 展开更多
关键词 Marine-continental tansitional fades 0rganic-nich shale Shale gas Exploration potential CARBONIFEROUS Northem border area between Guizhou and Yunnan China
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Mechanical behavior analysis of high power commercial lithium-ion batteries
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作者 Ruicheng Shen Shaojun Niu +2 位作者 Guobin Zhu Kai Wu Honghe Zheng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第6期315-322,共8页
In application,lithium-ion cells undergo expansion during cycling.The mechanical behavior and the impact of external stress on lithium-ion battery are important in vehicle application.In this work,18 Ah high power com... In application,lithium-ion cells undergo expansion during cycling.The mechanical behavior and the impact of external stress on lithium-ion battery are important in vehicle application.In this work,18 Ah high power commercial cell with Li Ni_(0.5)Co_(0.2)Mn_(0.3)O_(2)/graphite electrode were adopted.A commercial compress machine was applied to monitor the mechanical characteristics under different stage of charge(SOC),lifetime and initial external force.The dynamic and steady force was obtained and the results show that the dynamic force increases as the SOC increasing,obviously.During the lifetime with high power driving mode,different external force is shown to have a great impact on the long-term cell performance,with higher stresses result in higher capacity decay rates and faster impedance increases.A proper initial external force(900 N)provides lower impedance increasing.Postmortem analysis of the cells with2000 N initial force suggests a close correlation between electrochemistry and mechanics in which higher initial force leads to higher direct current internal resistance(DCIR)increase rate.In addition,for the cell with higher external force,deformation of the cathode and thicker solid electrolyte interface(SEI)film on the surface of anode and separator are observed.Porosity reduction and closure was also verified after cycles which is an obstacle to the lithium ion transferring.The largest cause of the observed capacity decline was the loss of active lithium through autopsy analysis.In addition,for the cell with higher external force,deformation of the cathode and thicker SEI film on the surface of anode and separator are observed.Porosity reduction and closure was also verified after cycles which is an obstacle to the lithium ion transferring.The largest cause of the observed capacity decline was the loss of active lithium through autopsy analysis. 展开更多
关键词 Lithium-ion batteries External mechanical pressure Capacity fade Static pressure Dynamic pressure
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Robust or nonrobust: On MC-DS-CDMA acquisition in LEO satellite communications
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作者 Entong Meng Xiangyuan Bu +2 位作者 Jihong Yu Jianping An Xuanhe Yang 《Digital Communications and Networks》 SCIE CSCD 2023年第4期896-905,共10页
Low Earth Orbit(LEO)satellite communications can provide global coverage in the sixth generation communication(6G)networks.To combat the strong Partial Band Interferences(PBIs)and multipath fading in LEO satellite com... Low Earth Orbit(LEO)satellite communications can provide global coverage in the sixth generation communication(6G)networks.To combat the strong Partial Band Interferences(PBIs)and multipath fading in LEO satellite communication systems,the Multicarrier Direct Sequence Code Division Multiple Access(MC-DS-CDMA)technique is a promising alternative to the traditional Single-carrier Direct Sequence Code Division Multiple Access(SC-DS-CDMA)system for its advantages of high bandwidth efficiency,superior interference rejection capability,and low complexity of parallel signal processing.However,limited studies have been conducted on the performance analysis of MC-DS-CDMA acquisition systems in the presence of a large Doppler shift,a unique characteristic of LEO satellite communications.To bridge this gap,we investigate the performance of MC-DS-CDMA systems with two-dimensional acquisition and noncoherent equal gain combining over Rician fading channel in the presence of the Doppler shift and PBIs.The performance metrics are detection probability and Mean Square Error(MSE)of the Doppler factor and delay.Specifically,we derive the closed-form expressions for the MSE and the Probability Density Function(PDF)of the acquisition decision variable and obtain the detection probability.We conduct extensive numerical experiments to verify the theoretical analysis and performance gain of MC-DSCDMA over the SC-DS-CDMA.The results show that MC-DS-CDMA with two-dimensional acquisition is more robust to multipath Rician fading than SC-DS-CDMA.Moreover,MC-DS-CDMA outperforms SC-DS-CDMA regarding the detection probability and MSE when combating the strong PBIs. 展开更多
关键词 Satellite communications MC-DS-CDMA Acquisition performance Rician fading channel Partial band interference
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Optimizing Power Allocation for D2D Communication with URLLC under Rician Fading Channel:A Learning-to-Optimize Approach
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作者 Owais Muhammad Hong Jiang +2 位作者 Mushtaq Muhammad Umer Bilal Muhammad Naeem Muhammad Ahtsam 《Intelligent Automation & Soft Computing》 SCIE 2023年第9期3193-3212,共20页
To meet the high-performance requirements of fifth-generation(5G)and sixth-generation(6G)wireless networks,in particular,ultra-reliable and low-latency communication(URLLC)is considered to be one of the most important... To meet the high-performance requirements of fifth-generation(5G)and sixth-generation(6G)wireless networks,in particular,ultra-reliable and low-latency communication(URLLC)is considered to be one of the most important communication scenarios in a wireless network.In this paper,we consider the effects of the Rician fading channel on the performance of cooperative device-to-device(D2D)communication with URLLC.For better performance,we maximize and examine the system’s minimal rate of D2D communication.Due to the interference in D2D communication,the problem of maximizing the minimum rate becomes non-convex and difficult to solve.To solve this problem,a learning-to-optimize-based algorithm is proposed to find the optimal power allocation.The conventional branch and bound(BB)algorithm are used to learn the optimal pruning policy with supervised learning.Ensemble learning is used to train the multiple classifiers.To address the imbalanced problem,we used the supervised undersampling technique.Comparisons are made with the conventional BB algorithm and the heuristic algorithm.The outcome of the simulation demonstrates a notable performance improvement in power consumption.The proposed algorithm has significantly low computational complexity and runs faster as compared to the conventional BB algorithm and a heuristic algorithm. 展开更多
关键词 D2D URLLC rician fading supervised learning
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The Sun’s Rotation Appears Differential plus Other New Views
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作者 Salah Abunaieb 《Natural Science》 CAS 2023年第4期167-178,共12页
This is a fresh perspective on the sun that considers its huge spherical size in relation to the finite speed of light. The sun is so extended that it takes light approximately 2.32 seconds to travel from the plane of... This is a fresh perspective on the sun that considers its huge spherical size in relation to the finite speed of light. The sun is so extended that it takes light approximately 2.32 seconds to travel from the plane of the solar limb to the plane tangential to the sun at the solar disc’s center. The aforementioned information is utilized in this study to support the new viewpoints. Firstly, it is shown that the solar disc is a simultaneous view of successively emitted coaxial spherical circles. Secondly, despite the fact that the sun is gaseous, it is thought to revolve completely as a rigid body at a fixed angular speed, yet an observer on Earth sees it rotate differentially. In a simple mathematical approach, it is found that the sun’s rotational speed apparently decreases with latitude. Thirdly, a qualitative examination of how we observe simultaneous whole-surface brightness changes of the sun and sunlike stars indicates that such changes would appear to spread out radially from the center of the solar disc. 展开更多
关键词 Sun Differential Rotation Solar Radius Solar Disc Speed of Light Special Theory of Relativity Fading Stars
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Secure Wireless Multicasting through Nakagami-m Fading Channels with Multi-Hop Relaying
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作者 Md. Mizanur Rahman Md. Zahurul Islam Sarkar Mohammad Mahmud Hasan 《Journal of Computer and Communications》 2023年第5期177-193,共17页
The additional diversity gain provided by the relays improves the secrecy capacity of communications system significantly. The multiple hops in the relaying system is an important technique to improve this diversity g... The additional diversity gain provided by the relays improves the secrecy capacity of communications system significantly. The multiple hops in the relaying system is an important technique to improve this diversity gain. The development of an analytical mathematical model of ensuring security in multicasting through fading channels incorporating this benefit of multi-hop relaying is still an open problem. Motivated by this issue, this paper considers a secure wireless multicasting scenario employing multi-hop relaying technique over frequency selective Nakagami-m fading channel and develops an analytical mathematical model to ensure the security against multiple eavesdroppers. This mathematical model has been developed based on the closed-form analytical expressions of the probability of non-zero secrecy multicast capacity (PNSMC) and the secure outage probability for multicasting (SOPM) to ensure the security in the presence of multiple eavesdroppers. Moreover, the effects of the fading parameter of multicast channel, the number of hops and eavesdropper are investigated. The results show that the security in multicasting through Nakagami-m fading channel with multi-hop relaying system is more sensitive to the number of hops and eavesdroppers. The fading of multicast channel helps to improve the secrecy multicast capacity and is not the enemy of security in multicasting. 展开更多
关键词 Frequency Selective Fading Multi-Hop Relaying Probability of Non-Zero Secrecy Multicast Capacity Secure Outage Probability for Multicasting
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电子音乐中Fade In及Fade Out效果应用 被引量:1
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作者 潘广宇 《歌海》 2008年第6期26-27,共2页
在电子音乐处理手法多如牛毛的今天,人们对电子音乐审美正随着电子音乐地发展而提高。但劣质CD音乐同时抑制着电子音乐的整体发展,影响人们的音乐审美。因此,本文通过对音乐Fade-In及Fade-Out音频前期制作中的情绪辅助表达、录音过程中... 在电子音乐处理手法多如牛毛的今天,人们对电子音乐审美正随着电子音乐地发展而提高。但劣质CD音乐同时抑制着电子音乐的整体发展,影响人们的音乐审美。因此,本文通过对音乐Fade-In及Fade-Out音频前期制作中的情绪辅助表达、录音过程中的音频剪辑、CD成品刻录中的防止爆破三种作用的研究,力图在尽量保持电子音乐高品质的同时,不断的尝试新的操作构思,为电子音乐地发展创新锦上添花。 展开更多
关键词 FADE In及Fade OUT 电子音乐 音频
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移动无线信道的符号/序列TCM DS/SSMA系统的设计和性能分析(英文)
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作者 仰枫帆 毕光国 许宗泽 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第1期26-32,共7页
基于低码率TCM构造了一种新型多维符号/序列TCM,它的纠错冗余由编码符号序列和扩谱伪随机序列共同提供。我们运用理论分析和数值模拟方法研究了在平坦瑞利衰落信道下采用该符号/序列TCM的直扩多址系统的性能。结果显示在相... 基于低码率TCM构造了一种新型多维符号/序列TCM,它的纠错冗余由编码符号序列和扩谱伪随机序列共同提供。我们运用理论分析和数值模拟方法研究了在平坦瑞利衰落信道下采用该符号/序列TCM的直扩多址系统的性能。结果显示在相同的条件下,采用符号/序列TCM的直扩多址系统较采用传统TCM的直扩多址系统具有更优越的性能。 展开更多
关键词 TRELLIS coded modulation direct sequence spread spectrun multiple access Rayleigh FADING channel MAXIMAL LIKELIHOOD decaling probability of bit error rate
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无编程和填表制导开发环境FADE
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作者 陈启泉 吴清江 陈维斌 《计算机工程与应用》 CSCD 北大核心 1992年第9期50-55,共6页
本文介绍无编程软件应用系统开发环境FADE的设计思想,论述无编程开发工具的类型和特点,填表式制导开发方式的应用系统的生成过程,并给出了表格数据库的文法和语义描述。
关键词 FADE 程序设计
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A PRELIMINARY STUDY ON THE TECTONICS AND EVOLUTION OF THE FUJIAN COAST CHANGLE-NANAO METAMORPHISM ZONE
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作者 汪新 张月红 +2 位作者 陈文山 杨小青 黄辉 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1995年第3期226-232,共7页
The Fujian coast Changle-Nanao metamorphism zone rocks are composed of gneiss, schist andhornblendite which had gone through metamorphism of amphilbolite facies, and followed the large-scaleintrusive mass of gneissic ... The Fujian coast Changle-Nanao metamorphism zone rocks are composed of gneiss, schist andhornblendite which had gone through metamorphism of amphilbolite facies, and followed the large-scaleintrusive mass of gneissic granite. The zone was orginally composed of Early Palaeozoiccontinental margin and island arc volcanic and sedimentary rocks. In 180-150 Ma, the zone undermentductile shear deformation and amphibolite facies metamorphism; and in 130-80 Ma, rose rap1dly andco1lided with the Southeastem China continen1al rnargln volonic rocks a10ng the NE trending ductileshear belt. The above geologic setting laid the present Fujian coast tectonic foundation whose formationand evolution are known to be interrlatal with the sueduction and collision of the Taiwan CentralRange. 展开更多
关键词 Changle-Nanao METAMORPHIC ZONE Mesozoic TECTONICS AMPHIBOLITE fades
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The Influence of LOS Components on the Statistical Properties of the Capacity of Amplify-and-Forward Channels
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作者 Gulzaib RAFIQ Matthias PATZOLD 《Wireless Sensor Network》 2009年第1期7-14,共8页
Amplify-and-forward channels in cooperative networks provide a promising improvement in the network coverage and system throughput. Under line-of-sight (LOS) propagation conditions in such cooperative networks, the ov... Amplify-and-forward channels in cooperative networks provide a promising improvement in the network coverage and system throughput. Under line-of-sight (LOS) propagation conditions in such cooperative networks, the overall fading channel can be modeled by a double Rice process. In this article, we have stud-ied the statistical properties of the capacity of double Rice fading channels. We have derived the analytical expressions for the probability density function (PDF), cumulative distribution function (CDF), level- crossing rate (LCR), and average duration of fades (ADF) of the channel capacity. The obtained results are studied for different values of the amplitudes of the LOS components in the two links of double Rice fading channels. It has been observed that the statistics of the capacity of double Rice fading channels are quite dif-ferent from those of double Rayleigh and classical Rice fading channels. Moreover, the presence of an LOS component in any of the two links increases the mean channel capacity and the LCR of the channel capacity. The validity of the theoretical results is confirmed by simulations. The results presented in this article can be very useful for communication system designers to optimize the performance of cooperative networks in wireless communication systems. 展开更多
关键词 AMPLIFY-AND-FORWARD CHANNELS Channel Capacity Cooperative Networks LINE-OF-SIGHT Component DOUBLE Rice PROCESS DOUBLE Rayleigh PROCESS Level-Crossing Rate Average Duration of fades
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一种MIMO相关信道的建模方法 被引量:2
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作者 程鑫豪 赵民建 李式巨 《电路与系统学报》 CSCD 北大核心 2007年第6期33-37,共5页
本文阐述MIMO相关信道的建模方法。该建模方法通过计算MIMO系统多天线之间的空间相关矩阵,在MIMO非相关信道的建模基础上生成MIMO相关信道。
关键词 MIMO Jakes’Fading MODEL 空间相关
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应用FADE品质改善模式改善新入院病人护理细节质量 被引量:4
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作者 佐小丽 郗君梅 +3 位作者 钟琼 罗丹 余颖 刘莉 《护理学报》 2017年第10期14-16,共3页
目的应用FADE[focus(确认问题);analyze(问题分析,指出需要了解的事项,并收集资料以决定影响因素);develop(建立计划以解决问题);execute(执行改善计划并追综检讨,FADE]品质改善模式,持续改进新入院病人护理细节质量,确保病人安全。方法... 目的应用FADE[focus(确认问题);analyze(问题分析,指出需要了解的事项,并收集资料以决定影响因素);develop(建立计划以解决问题);execute(执行改善计划并追综检讨,FADE]品质改善模式,持续改进新入院病人护理细节质量,确保病人安全。方法 2014年11月—2015年6月应用FADE品质改善模式,确认改进问题为"新入院病人护理细节质量",找出影响新入院病人护理细节质量的主要问题,并针对问题进行根因分析找出影响因素,制定新入院病人护理细节质量标准、改进目标及改进策略,执行计划并追踪检讨持续改进,运用数据评价改进效果。结果实施改进前2014年11月新入院病人护理细节质量合格率为77.9%,实施改进后,2015年1—6月共检查6次,新入院病人护理细节质量平均合格率为92.2%,实施前后合格率比较,差异有统计学意义(P<0.01),有效改进了新入院病人护理工作中存在的问题。结论应用FADE品质改善模式,有效改进了新入院病人护理中存在的问题,提高了新入院病人护理细节质量,确保了病人安全。 展开更多
关键词 FADE品质改善模式 新入院病人护理质量 持续改进
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解读grandMA3控制台的收光走位(MIB)功能
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作者 施端 《演艺科技》 2021年第11期1-6,10,共7页
本文主要阐述grandMA3控制台的收光走位功能,包括收光走位模式、收光走位偏好、收光走位延迟时间、收光走位变化时间、收光走位多步骤及其相关内容。
关键词 grandMA3 收光走位(MIB) 收光走位模式(MIB Mode) 收光走位偏好(MIB Preference) 收光走位延迟时间(MIB Delay) 收光走位变化时间(MIB Fade) 收光走位多步骤(MIB MultiStep)
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The New Form of Time-Dependent Mild Slope Equation for Random Waves 被引量:21
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作者 Zhang Yonggang , Li Yucheng Teng Bin Doctor Degree Candidate, The National Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116023Professor, The National,Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116023Associate Professor, The National Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116023 《China Ocean Engineering》 SCIE EI 1995年第4期387-394,共8页
The mild-slope equation derived by Berkhoff (1972), has widely been used in the numerical calculation of refraction and diffraction of regular waves. However, it is well known that the random sea waves has a significa... The mild-slope equation derived by Berkhoff (1972), has widely been used in the numerical calculation of refraction and diffraction of regular waves. However, it is well known that the random sea waves has a significant effect in the refraction and diffraction problems. In this paper, a new form of time-dependent mild slope equation for irregular waves was derived with Fade approximation and Kubo’s time series concept. The equation was simplified using WKB method, and simple and practical irregular mild slope equation was obtained. Results of numerical calculations are compared with those of laboratory experiments. 展开更多
关键词 random wave MILD SLOPE EQUATION FADE approximation WKB method simulation
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Mechanism of Capacity Fading Caused by Mn(Ⅱ)Deposition on Anodes for Spinel Lithium Manganese Oxide Cell 被引量:7
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作者 陈海辉 MA Tianyi +2 位作者 ZENG Yingying GUO Xiuyan 邱新平 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第1期1-10,共10页
The capacity fade of spinel lithium manganese oxide in lithium-ion batteries is a bottleneck challenge for the large-scale application.The traditional opinion is that Mn(Ⅱ) ions in the anode are reduced to the metall... The capacity fade of spinel lithium manganese oxide in lithium-ion batteries is a bottleneck challenge for the large-scale application.The traditional opinion is that Mn(Ⅱ) ions in the anode are reduced to the metallic manganese that helps for catalyzing electrolyte decomposition.This could poison and damage the solid electrolyte interface(SEI) film,leading to the the capacity fade in Li-ion batteries.We propose a new mechanism that Mn(Ⅱ) deposites at the anode hinders and/or blocks the intercalation/de-intercalation of lithium ions,which leads to the capacity fade in Li-ion batteries.Based on the new mechanism assumption,a kind of new structure with core-shell characteristic is designed to inhabit manganese ion dissolution,thus improving electrochemical cycle performance of the cell.By the way,this mechanism hypothesis is also supported by the results of these experiments.The LiMn_(2-x)Ti_xO_4 shell layer enhances cathode resistance to corrosion attack and effectively suppresses dissolution of Mn,then improves battery cycle performance with LiMn_2O_4 cathode,even at high rate and elevated temperature. 展开更多
关键词 capacity fade manganese deposition lithium manganese oxide core-shell structure
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Adaptive Maneuvering Frequency Method of Current Statistical Model 被引量:12
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作者 Wei Sun Yongjian Yang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第1期154-160,共7页
Current statistical model(CSM) has a good performance in maneuvering target tracking. However, the fixed maneuvering frequency will deteriorate the tracking results, such as a serious dynamic delay, a slowly convergin... Current statistical model(CSM) has a good performance in maneuvering target tracking. However, the fixed maneuvering frequency will deteriorate the tracking results, such as a serious dynamic delay, a slowly converging speedy and a limited precision when using Kalman filter(KF) algorithm. In this study, a new current statistical model and a new Kalman filter are proposed to improve the performance of maneuvering target tracking. The new model which employs innovation dominated subjection function to adaptively adjust maneuvering frequency has a better performance in step maneuvering target tracking, while a fluctuant phenomenon appears. As far as this problem is concerned, a new adaptive fading Kalman filter is proposed as well. In the new Kalman filter, the prediction values are amended in time by setting judgment and amendment rules,so that tracking precision and fluctuant phenomenon of the new current statistical model are improved. The results of simulation indicate the effectiveness of the new algorithm and the practical guiding significance. 展开更多
关键词 Current statistical model(CSM) maneuvering target tracking adaptive fading Kalman filter(AFKF)
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Robust cubature Kalman filter method for the nonlinear alignment of SINS 被引量:5
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作者 Shi-luo Guo Ying-jie Sun +1 位作者 Li-min Chang Yang Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第2期593-598,共6页
Nonlinear initial alignment is a significant research topic for strapdown inertial navigation system(SINS).Cubature Kalman filter(CKF)is a popular tool for nonlinear initial alignment.Standard CKF assumes that the sta... Nonlinear initial alignment is a significant research topic for strapdown inertial navigation system(SINS).Cubature Kalman filter(CKF)is a popular tool for nonlinear initial alignment.Standard CKF assumes that the statics of the observation noise are pre-given before the filtering process.Therefore,any unpredicted outliers in observation noise will decrease the stability of the filter.In view of this problem,improved CKF method with robustness is proposed.Multiple fading factors are introduced to rescale the observation noise covariance.Then the update stage of the filter can be autonomously tuned,and if there are outliers exist in the observations,the update should be less weighted.Under the Gaussian assumption of KF,the Mahalanobis distance of the innovation vector is supposed to be Chi-square distributed.Therefore a judging index based on Chi-square test is designed to detect the noise outliers,determining whether the fading tune are required.The proposed method is applied in the nonlinear alignment of SINS,and vehicle experiment proves the effective of the proposed method. 展开更多
关键词 SINS Nonlinear alignment Cubature Kalman filter ROBUST Multiple fading factors Hypothesis test
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