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Interacting bosons on a four-leg flux ladder
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作者 Dian-Cheng Zhang Shi-Jie Yang 《Communications in Theoretical Physics》 2025年第3期174-179,共6页
We conduct a dynamical Gutzwiller mean-field study of interacting bosons on a four-leg ladder,subject to a uniform flux.The ground states dependent on the magnetic flux and kinetic tunneling strength are explored.Cons... We conduct a dynamical Gutzwiller mean-field study of interacting bosons on a four-leg ladder,subject to a uniform flux.The ground states dependent on the magnetic flux and kinetic tunneling strength are explored.Consequently,we identify the super-vortical lattice,as well as the inner-Meissner phase,which presents Meissner currents just along the intimal legs within the flux ladder.The staggered-current phase is also allowed,with its formation condition altered because of the four-leg construction.The number of legs on the flux ladder can make an effect. 展开更多
关键词 interacting bosons flux ladder Meissner phase vortical lattice
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Topological Design of Low Dielectric Ladder-like Polysilsesquioxane and Copolymers
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作者 Wen-Jie Fan Meng Xie +3 位作者 Jin-Feng Tian Yan He Shuang Xia Wen-Xin Fu 《Chinese Journal of Polymer Science》 2025年第3期477-487,共11页
Low dielectric constant(low-k)materials are critical for advanced packaging in high-density microelectronic devices and high-frequency communication technologies.Ladder polysiloxanes,which are characterized by their u... Low dielectric constant(low-k)materials are critical for advanced packaging in high-density microelectronic devices and high-frequency communication technologies.Ladder polysiloxanes,which are characterized by their unique double-chain structure and intrinsic microporosity,offer remarkable advantages in terms of thermal stability,oxidation resistance,and dielectric performance.However,structural defects in ladder polysiloxanes,such as cage-like and irregular oligomers,and their effects on dielectric properties remain underexplored.In this study,a series of ladder-like polysiloxanes(X-TMS)with diverse side groups weresynthesized via a one-step base-catalyzed method.The influence of the benzocyclobutene(BCB)side groups on the formation of regular ladder structures was systematically investigated.Notably,BCB incorporation disrupted the structural regularity,favoring the formation of cage-like and irregular topologies,which were extensively characterized using 29silicon nuclear magnetic resonance spectroscopy(^(29)Si-NMR),Fourier transform infrared spectroscopy(FTIR),gel permeation chromatography(GPC),and X-ray diffraction(XRD).These structural defects were beneficial for improving the hydrophobicity and thermal stability.Copolymerization of X-TMS with commercial DVS-BCB resins further enhanced the mechanical properties,with the elastic modulus increasing from 3.6 GPa to 4.4 GPa and water absorption reduced from 0.33 wt%to 0.06 wt%.This study establishes a clear correlation between topological structures and material properties.These findings not only advance the understanding of the structure-property relationships in ladder polysiloxanes but also provide a novel approach for designing high-performance interlayer dielectric materials for next-generation microelectronics. 展开更多
关键词 ladder polymer Topological structures POLYSILOXANES Low dielectric BENZOCYCLOBUTENE
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External application of traditional Chinese medicine in combination with threestep analgesic ladder therapy for cancer-induced bone pain:a systematic review and meta-analysis
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作者 Fei WANG Guihua LAI +4 位作者 Fang ZHOU Duorui NIE Xiongtao CHENG Yue WANG Jianxiong CAO 《Digital Chinese Medicine》 2025年第1期59-75,共17页
Objective To systematically evaluate the overall efficacy of external application of traditional Chinese medicine(EA-TCM)in combination with oral three-step analgesic ladder therapy for patients suffering from cancer-... Objective To systematically evaluate the overall efficacy of external application of traditional Chinese medicine(EA-TCM)in combination with oral three-step analgesic ladder therapy for patients suffering from cancer-induced bone pain(CIBP).Methods We conducted a literature search of randomized controlled trials on the combination of EA-TCM and three-step analgesic ladder therapy for CIBP across ten databases and two registration systems.It included four Chinese databases[Chinese Biomedical Literature Database(SinoMed),China National Knowledge Infrastructure(CNKI),Wanfang Database,and China Science and Technology Journal Database(VIP)],six English databases(Scopus,Embase,Web of Science,PubMed,Cochrane Library,and OpenGrey),and two registration systems(Chinese Clinical Trial Registry and ClinicalTrials.gov).The timeframe for the literature search extended from the inception of each database to December 31,2023.Meta-analysis was performed using RevMan(v5.4.1),and the outcome indicators(pain relief rate,analgesic duration,quality of life,pain intensity,breakthrough pain frequency,and adverse reactions)were graded using GRADE profiler(v3.6).Results According to the established inclusion and exclusion criteria,a total of 43 studies was deemed eligible,involving 3142 participants with CIBP.The results of meta-analysis showed that compared with oral three-step analgesic ladder therapy alone,the combined therapy of EA-TCM and three-step analgesic ladder has a significant improvement in pain relief rate[risk ratio(RR)=1.32,95%confidence interval(CI):1.24 to 1.41,P<0.00001],analgesic duration[mean difference(MD)=1.33,95%CI:0.97 to 1.69,P<0.00001],and quality of life(MD=5.66,95%CI:4.88 to 6.44,P<0.00001).Furthermore,the combined therapy significantly reduced pain intensity(MD=-1.00,95%CI:-1.19 to-0.80,P<0.00001),breakthrough pain frequency(MD=-0.43,95%CI:-0.51 to-0.36,P<0.00001),and adverse reactions(RR=0.60,95%CI:0.53 to 0.68,P<0.00001)in CIBP patients.Based on the GRADE assessment,the level of evidence varied from low to moderate.Conclusion EA-TCM combined with the three-step analgesic ladder therapy can effectively alleviate pain symptoms in patients with CIBP and improve their quality of life.Additionally,the EA-TCM can effectively reduce the incidence of adverse reactions associated with threestep analgesic therapy. 展开更多
关键词 External application of traditional Chinese medicine(EA-TCM) Three-step analgesic ladder therapy Cancer-induced bone pain(CIBP) Systematic review META-ANALYSIS
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Ladder型三能级介质中传播的少周期激光脉冲的空间分布 被引量:3
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作者 王蕾 王振东 +1 位作者 梁变 樊锡君 《计算物理》 EI CSCD 北大核心 2011年第1期81-86,共6页
利用由时域有限差分法和预估校正法求得全波Maxwell-Bloch方程的数值解,研究少周期超短激光脉冲在Ladder型三能级原子介质中传播时脉冲及介质粒子布居的空间分布.结果表明,脉冲及介质粒子布居的空间分布规律随脉冲面积的改变而发生明显... 利用由时域有限差分法和预估校正法求得全波Maxwell-Bloch方程的数值解,研究少周期超短激光脉冲在Ladder型三能级原子介质中传播时脉冲及介质粒子布居的空间分布.结果表明,脉冲及介质粒子布居的空间分布规律随脉冲面积的改变而发生明显的变化.当脉冲面积较小时,脉冲形状不规则,振荡次数较多;当脉冲面积较大时,脉冲形状变得较为规则,振荡次数明显减少.随着脉冲面积的增大,脉冲振幅和传播速度逐渐增大,各能级粒子布居振荡次数增多,不同时刻的脉冲和粒子布居空间分布的变化明显减小.粒子布居的空间分布与脉冲的空间分布密切相关. 展开更多
关键词 少周期激光脉冲 传播 ladder型三能级 空间分布
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移液器使用不当导致DNA分型Ladder污染原因初探 被引量:5
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作者 王玉健 朱巍 +1 位作者 杨智 匡金枝 《中国法医学杂志》 CSCD 2014年第6期573-574,共2页
在法医DNA分型检验中,如出现与等位基因标准对照物(Ladder)一样的等位基因,应注意Ladder污染[1]。本文对由于移液器使用不当,造成其头部或管道内壁DNA蓄积而导致Ladder污染原因进行分析,希望为相关检验提供借鉴。1材料与方法1.1样本 ... 在法医DNA分型检验中,如出现与等位基因标准对照物(Ladder)一样的等位基因,应注意Ladder污染[1]。本文对由于移液器使用不当,造成其头部或管道内壁DNA蓄积而导致Ladder污染原因进行分析,希望为相关检验提供借鉴。1材料与方法1.1样本 收集本实验室扩增区生物安全柜内5支日常使用的移液器(量程分别为200μL、100μL、20μL、10μL和2μL),分别用超纯水清洗,取其清洗液为样本(共5份),取用日常使用的移液器分装的PowerPlex 18D System试剂盒(简称PP18D)内的扩增混合物、引物和试剂盒内扩增用超纯水为样本(共3份),以上共计8份样本为待测DNA模板。 展开更多
关键词 法医物证学 法医DNA实验室 蓄积污染 ladder样图谱 溯源检验
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降解检材STR分型Ladder-Like条带形成原因的探讨 被引量:1
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作者 楼迪栋 余纯应 +3 位作者 黄代新 赵贵森 任文 杨庆恩 《中国法医学杂志》 CSCD 2005年第6期332-334,共3页
目的探讨降解DNA短串联重复序列PCR扩增产物在PAGE中Ladder-L ike条带的形成原因。方法用一组人工合成的不同长度的D8S1179DNA单链,模拟降解检材中的断裂DNA;利用John M设计的D8S1179引物对模拟模板的DNA单链进行PCR扩增,PAGE分离。结... 目的探讨降解DNA短串联重复序列PCR扩增产物在PAGE中Ladder-L ike条带的形成原因。方法用一组人工合成的不同长度的D8S1179DNA单链,模拟降解检材中的断裂DNA;利用John M设计的D8S1179引物对模拟模板的DNA单链进行PCR扩增,PAGE分离。结果不同模拟模板的DNA单链的组合可以扩增出不同的Lad-der-L ike条带。结论短串联重复序列Ladder-like条带是PCR过程中降解DNA多态区互补扩增的产物。 展开更多
关键词 法医物证学 短串联重复序 ladder-like条带 PCR—STR分型降解检材 降解检材
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利用基频与倍频脉冲控制扩展“ladder”式跃迁
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作者 牛英煜 王荣 +1 位作者 邱明辉 修俊玲 《物理学报》 SCIE EI CAS CSCD 北大核心 2016年第23期77-84,共8页
利用含时量子波包动力学方法研究了两束基频与倍频脉冲控制下的扩展"ladder"式跃迁.通过基频与2倍频脉冲控制分子布居从|0,0>态跃迁至|5,0>与|5,2>态;基频与3倍频脉冲控制分子布居从|0,0>态跃迁至|5,3?与|6,2>... 利用含时量子波包动力学方法研究了两束基频与倍频脉冲控制下的扩展"ladder"式跃迁.通过基频与2倍频脉冲控制分子布居从|0,0>态跃迁至|5,0>与|5,2>态;基频与3倍频脉冲控制分子布居从|0,0>态跃迁至|5,3?与|6,2>态.计算结果表明,利用两束基频与倍频脉冲,通过"ladder"式跃迁,可以得到近100%的布居跃迁概率.两束脉冲间的相对相位角影响分子的布居分布.当脉冲频率比为1:2时,布居以π为周期变化;当脉冲频率比为1:3时,布居以2π为周期变化. 展开更多
关键词 ladder”式跃迁 波包 相对相位角 基频脉冲
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LADDER SUPERSTRUCTURE-DIRECTED SYNTHESIS OF A WELL-DEFINED m-PHENELENEDIIMINO-BRIDGED LADDER POLYMETHYLSILOXANE 被引量:1
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作者 万有志 张榕本 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2009年第4期525-532,共8页
A well-defined m-phenylenediimino-bridged ladder polymethylsiloxane(LP) was first synthesized through a welldefined ladder superstructure(LS) acting as synthetic template,which was self-assembled by concerted interact... A well-defined m-phenylenediimino-bridged ladder polymethylsiloxane(LP) was first synthesized through a welldefined ladder superstructure(LS) acting as synthetic template,which was self-assembled by concerted interaction of hydrogen bonding and aromaticπ-πstacking of the monomer(M),N,N'-bis(phenyldichlorosilyl)-m-phenylenediamine.Some key characterization data of LP and,in particular,the extremely vulnerable LS with very unstable Si-Cl and Si-N groups were given.The molecular weights(M_n) of LS and LP are 5... 展开更多
关键词 ladder superstructure Organo-bridged ladder polysiloxane SELF-ASSEMBLY
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三能级Upper-ladder型系统中的无反转激光相位扩散效应(英文)
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作者 朱孟正 赵春然 尹新国 《发光学报》 EI CAS CSCD 北大核心 2011年第2期174-178,共5页
三能级Upper-ladder型系统中,在旋波、慢变振幅近似下,求解了考虑驱动场相位扩散后的系统密度矩阵运动方程,并给出了这个三能级梯型系统稳态线性解析解。利用对密度矩阵运动方程的稳态线性解析解的数值模拟结果,研究相位扩散对无反转激... 三能级Upper-ladder型系统中,在旋波、慢变振幅近似下,求解了考虑驱动场相位扩散后的系统密度矩阵运动方程,并给出了这个三能级梯型系统稳态线性解析解。利用对密度矩阵运动方程的稳态线性解析解的数值模拟结果,研究相位扩散对无反转激光增益、色散和粒子数差的影响;利用对密度矩阵运动方程的数值模拟结果,分析相位的扩散对无反转激光场及相应的各能级粒子数布居的时间演化规律的影响。驱动场相位扩散会导致无反转激光增益减小。线宽的存在阻碍了系统的无吸收高色散。线宽的变化不能改变ladder型系统输出(反转还是无反转)激光的特性。但线宽影响了系统达到稳态的时间以及时间演化过程中的相位扩散将导致相干的减弱。 展开更多
关键词 激光物理 相位扩散 ladder型系统
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单位点等位基因Ladder的研制与应用 被引量:1
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作者 金鑫 刘金杰 +2 位作者 刘正 姜伯玮 金川 《警察技术》 2017年第1期79-81,共3页
DNA等位基因Ladder是国产遗传分析仪质量检测及性能评价的必备试剂。基于DNA克隆技术,以单基因座(D2S1338)为靶位点,通过体外基因扩增方法获取基因座重复单位为11-24的等位基因,并与相应克隆载体连接构建该位点质粒克隆库,采用优选出的... DNA等位基因Ladder是国产遗传分析仪质量检测及性能评价的必备试剂。基于DNA克隆技术,以单基因座(D2S1338)为靶位点,通过体外基因扩增方法获取基因座重复单位为11-24的等位基因,并与相应克隆载体连接构建该位点质粒克隆库,采用优选出的荧光标记引物对质粒DNA模板进行荧光PCR扩增,最终获得单STR位点高质量的等位基因Ladder,完全满足GA118-16A型遗传分析仪的质量检测和性能测试要求。 展开更多
关键词 等位基因ladder GA118-16A型遗传分析仪 基因克隆
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Influence of Femtosecond Laser Parameters on Autler-Townes Splitting of Three-Level Ladder Molecules
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作者 李月华 略兴强 +1 位作者 郭玮 姚洪斌 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第2期128-133,I0001,共7页
We theoretically investigate the Autler-Townes (AT) splitting in the photoelectron spectra of three-level ladder K2 molecule driven by a pump-probe pulse via employing the time- dependent wave packet approach. The d... We theoretically investigate the Autler-Townes (AT) splitting in the photoelectron spectra of three-level ladder K2 molecule driven by a pump-probe pulse via employing the time- dependent wave packet approach. The dependence of AT splitting on two laser intensities and wavelengths are studied in detail. We firstly quantify these effects on peak shift and AT separation. The photoelectron spectra show double splitting with symmetric profiles, but with asymmetric profiles when the wavelength is changed. The magnitude of AT splitting increases with the pump laser intensity, but does not vary with probe intensity. The shifts of the absorption peaks and the splitting between AT doublet are predicted by using an analyt- ical fitting function when the intensity/wavelength of one of the two fields is changed. These novel results are of importance for the molecular spectroscopy and may further stimulate the first principles theoretical studies analytically. 展开更多
关键词 Autler-Townes splitting Photoelectron spectra Three-level ladder K2 molecule
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广东汉族人群Penta D基因座off-ladder稀有等位基因分析 被引量:1
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作者 兰菲菲 周伟宁 +1 位作者 陈延冰 丁红珂 《中国产前诊断杂志(电子版)》 2020年第1期24-27,共4页
目的分析广东汉族人群亲子鉴定中Penta D基因座出现在等位基因分型标准物(allelic ladder)之外(off-ladder,OL)的现象并计算/命名基因分型。方法采用Chelex-100法提取样本DNA,用PowerPlex■21体系进行PCR扩增后,毛细管电泳分析STR基因... 目的分析广东汉族人群亲子鉴定中Penta D基因座出现在等位基因分型标准物(allelic ladder)之外(off-ladder,OL)的现象并计算/命名基因分型。方法采用Chelex-100法提取样本DNA,用PowerPlex■21体系进行PCR扩增后,毛细管电泳分析STR基因座的等位基因分型。结果双亲三联体鉴定的父亲和孩子在Penta D基因座检测出OL等位基因,经过计算得出该OL等位基因的基因分型为21,不在Penta D基因座Allelic Ladder范围之内,是新的稀有等位基因。结论Penta D基因座的OL稀有等位基因21在广东汉族人群中有分布,稀有等位基因的鉴定及分型计算/命名对于提高该基因座在亲权鉴定和个体识别中的能力具有重要科学意义。 展开更多
关键词 亲子鉴定 Penta D基因座 off-ladder等位基因
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山定子抗苹果褐斑病菌侵染过程中 DNA ladder 与类 caspases 活性的检测 被引量:4
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作者 范涛 任斌 +1 位作者 韩青梅 黄丽丽 《干旱地区农业研究》 CSCD 北大核心 2015年第1期42-47,共6页
接种褐斑病菌分生孢子悬浮液于山定子与富士苹果叶片,接种后1、3 d和5 d取样,提取DNA,检测DNA ladder;提取样品粗蛋白,用特异性荧光底物检测粗蛋白中类caspase活性,探索山定子受褐斑病菌侵染过程中引起的细胞程序性死亡(PCD)与抗性的关... 接种褐斑病菌分生孢子悬浮液于山定子与富士苹果叶片,接种后1、3 d和5 d取样,提取DNA,检测DNA ladder;提取样品粗蛋白,用特异性荧光底物检测粗蛋白中类caspase活性,探索山定子受褐斑病菌侵染过程中引起的细胞程序性死亡(PCD)与抗性的关系,检测DNA ladder和类caspases活性变化的规律。研究发现:在接种后1、3 d和5 d,山定子和富士苹果叶片中没有明显DNA ladder的产生;受检测的YVADase、DEVDase、IETDase和VEIDase活性在接种后1 d和3 d没有显著变化,但在接种后5 d,活性均降低30%左右,显著低于对照。研究表明,山定子在褐斑病菌侵染过程中并没有DNA ladder产生,但却伴随着类caspase活性的下降。 展开更多
关键词 山定子 苹果褐斑病菌 侵染 DNA ladder 类caspases
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Rainbow Vertex-connection Number of Ladder and Mbius Ladder
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作者 刘慧敏 毛亚平 《Chinese Quarterly Journal of Mathematics》 2016年第4期399-405,共7页
A vertex-colored graph G is said to be rainbow vertex-connected if every two vertices of G are connected by a path whose internal vertices have distinct colors, such a path is called a rainbow path. The rainbow vertex... A vertex-colored graph G is said to be rainbow vertex-connected if every two vertices of G are connected by a path whose internal vertices have distinct colors, such a path is called a rainbow path. The rainbow vertex-connection number of a connected graph G, denoted by rvc(G), is the smallest number of colors that are needed in order to make G rainbow vertex-connected. If for every pair u, v of distinct vertices, G contains a rainbow u-v geodesic, then G is strong rainbow vertex-connected. The minimum number k for which there exists a k-vertex-coloring of G that results in a strongly rainbow vertex-connected graph is called the strong rainbow vertex-connection number of G, denoted by srvc(G). Observe that rvc(G) ≤ srvc(G) for any nontrivial connected graph G. In this paper, for a Ladder L_n,we determine the exact value of srvc(L_n) for n even. For n odd, upper and lower bounds of srvc(L_n) are obtained. We also give upper and lower bounds of the(strong) rainbow vertex-connection number of Mbius Ladder. 展开更多
关键词 vertex-coloring rainbow vertex-connection (strong) rainbow vertex-connection number ladder Mbius ladder
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DNALadder和ELISA联合检测PRRSV诱导Marc145细胞凋亡动态变化规律的研究 被引量:5
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作者 刘伍梅 汪铭书 +4 位作者 程安春 刘芳 李雪梅 张平英 陈孝跃 《四川农业大学学报》 CSCD 2005年第1期95-98,共4页
对PRRSV诱导Marc145细胞凋亡的动态变化规律进行了研究,实验收集PRRSV SC1株感染Marc145细胞后0、24、48、72、96、120、144h和同一时间点未接毒的细胞样品,用DNALadder定性检测和ELISA定量检测细胞凋亡的变化规律。定性检测结果表明,PR... 对PRRSV诱导Marc145细胞凋亡的动态变化规律进行了研究,实验收集PRRSV SC1株感染Marc145细胞后0、24、48、72、96、120、144h和同一时间点未接毒的细胞样品,用DNALadder定性检测和ELISA定量检测细胞凋亡的变化规律。定性检测结果表明,PRRSV能诱导Marc145细胞发生凋亡,病毒感染后凋亡细胞DNA电泳呈典型“梯状”条带。定量检测结果表明,Marc145细胞在PRRSV感染后24h开始出现凋亡,48h凋亡更加明显,72h达到高峰,明显高于对照组。 展开更多
关键词 DNA梯状图谱 酶联免疫吸附试验 猪繁殖和呼吸综合征病毒 细胞凋亡
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Semi-supervised Ladder Networks for Speech Emotion Recognition 被引量:9
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作者 Jian-Hua Tao Jian Huang +2 位作者 Ya Li Zheng Lian Ming-Yue Niu 《International Journal of Automation and computing》 EI CSCD 2019年第4期437-448,共12页
As a major component of speech signal processing, speech emotion recognition has become increasingly essential to understanding human communication. Benefitting from deep learning, many researchers have proposed vario... As a major component of speech signal processing, speech emotion recognition has become increasingly essential to understanding human communication. Benefitting from deep learning, many researchers have proposed various unsupervised models to extract effective emotional features and supervised models to train emotion recognition systems. In this paper, we utilize semi-supervised ladder networks for speech emotion recognition. The model is trained by minimizing the supervised loss and auxiliary unsupervised cost function. The addition of the unsupervised auxiliary task provides powerful discriminative representations of the input features, and is also regarded as the regularization of the emotional supervised task. We also compare the ladder network with other classical autoencoder structures. The experiments were conducted on the interactive emotional dyadic motion capture (IEMOCAP) database, and the results reveal that the proposed methods achieve superior performance with a small number of labelled data and achieves better performance than other methods. 展开更多
关键词 SPEECH EMOTION RECOGNITION the ladder network SEMI-SUPERVISED learning autoencoder REGULARIZATION
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Abstraction and operator characterization of fractal ladder viscoelastic hyper-cell for ligaments and tendons 被引量:2
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作者 Jianqiao GUO Yajun YIN Gexue REN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第10期1429-1448,共20页
This study investigates the viscoelastic behavior of soft bio-fibres in association with their fractal structures. A spring-dashpot fractal network with the self-similar topology, named the -type fractal ladder hyper-... This study investigates the viscoelastic behavior of soft bio-fibres in association with their fractal structures. A spring-dashpot fractal network with the self-similar topology, named the -type fractal ladder hyper-cell (FLHC), is abstracted from the micro/nano-structure of ligaments and tendons (LTs). Its constitutive operator is derived by the Heaviside operational calculus, which is of intrinsic fractional order. In terms of this operator, the long-term viscoelastic relaxation of bio-fibres arising from the fractal ladder topology is expounded. In addition, the fractional-order viscoelastic constitutive equation is obtained based on the FLHC of LTs, and its results are consistent with those of available human knee and spinal LT relaxation experiments. Results on the constitutive equation of FLHCs are formulated into two propositions. The multidisciplinary invariance and implications from the fractal ladder pattern of bio-fibres are also discussed. 展开更多
关键词 LIGAMENT and TENDON (LT) FRACTAL ladder topology operator method stress relaxation
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Investigation on thermal characteristics and desensitization mechanism of improved step ladder-structured nitrocellulose 被引量:2
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作者 Cheng-kai Pu Yu Luan +1 位作者 Ming-jun Yi Zheng-gang Xiao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第2期93-102,共10页
Nitrocellulose,or cellulose nitrate,has received considerable interest due to its various applications,such as propellants,coating agents and gas generators.However,its high mechanical sensitivity caused many accident... Nitrocellulose,or cellulose nitrate,has received considerable interest due to its various applications,such as propellants,coating agents and gas generators.However,its high mechanical sensitivity caused many accidents during its storage and usage in ammunition.In this work,two kinds of insensitive step ladderstructured nitrocellulose(LNC)with different nitrogen contents were synthesized.The products were characterized by FT-IR,Raman,XRD,SEM,elemental analysis,TGA,DSC,accelerating rate calorimeter analysis(ARC),and drop weight test to study their molecular structure,thermal characteristics and desensitization performance.Compared with raw nitrocellulose,LNC has a sharper exothermic peak in the DSC and ARC curves.The H50values of the two kinds of LNC increased from 25.76 to 30.01 cm for low nitrogen content and from 18.02 to 21.84 cm for high nitrogen content,respectively.The results show that the ladder-structure of LNC which provides regular molecular arrangement and a soft buffer made with polyethylene glycol could affect the energy releasing process of LNC and reduce the sensitivity of LNC.Insensitive LNC provides an alternative to be used as a binder in insensitive propellants formulation. 展开更多
关键词 NITROCELLULOSE DECOMPOSITION DESENSITIZATION ladder structure Thermal characteristic Polyethylene glycol
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Stable Vertical Ladder Climbing with Rung Recognition for a Four-limbed Robot 被引量:2
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作者 Xiao Sun Kenji Hashimoto +3 位作者 Shota Hayashi Masahiro Okawara Takashi Mastuzawa Atsuo Takanishi 《Journal of Bionic Engineering》 SCIE EI CSCD 2021年第4期786-798,共13页
This paper proposes a system for stable ladder climbing of the human-sized four-limbed robot“WAREC-1”,including the following 3 components:(a)Whole-body motion planning;(b)Rung recognition system and(c)Reaction forc... This paper proposes a system for stable ladder climbing of the human-sized four-limbed robot“WAREC-1”,including the following 3 components:(a)Whole-body motion planning;(b)Rung recognition system and(c)Reaction force adjustment.These 3 components guarantee appropriate ladder climbing motion,successful rung grub and proper reaction force distribution at contact points throughout the climbing motion,respectively.With this system,(1)Stable ladder climbing in 2-point contact gait by a human-sized robot and(2)Successful and stable climbing of an irregular ladder(with a higher or inclined rung)in both 3-point and 2-point contact gait with the capability of recognizing the target rung and the corresponding motion planning are realized,which have rarely been realized by former studies.Finally,experiment results and data of the robot ladder climbing are also presented to evaluate the proposed system. 展开更多
关键词 legged robot ladder climbing stability proximity sensor feedback force control
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Discrimination of neutron and gamma ray using the ladder gradient method and analysis of filter adaptability 被引量:2
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作者 Hao-Ran Liu Ming-Zhe Liu +3 位作者 Yu-Long Xiao Peng Li Zhuo Zuo Yi-Han Zhan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第12期105-115,共11页
This study proposes a ladder gradient method for neutron and gamma-ray discrimination.The proposed method exhibited state-of-the-art performance with low time consumption,which incorporates two parts:information extra... This study proposes a ladder gradient method for neutron and gamma-ray discrimination.The proposed method exhibited state-of-the-art performance with low time consumption,which incorporates two parts:information extraction and discrimination factor calculation.A quasi-continuous spiking cortical model was proposed to extract information from the radiation pulse signals,thus generating an ignition map corresponding to each pulse signal.The ignition map can be used to calculate the discrimination factor.A ladder gradient calculation was introduced to obtain a discrimination factor with low computational complexity.The proposed method was compared with five other discrimination methods to evaluate its robustness and efficacy.Furthermore,the filter adaptability of the pulse-coupled neural network and ladder gradient methods was investigated.Possible reasons for adapting the conditions with different discrimination methods and filters were analyzed.Experiments were conducted in 20 filtering situations with 11 types of filters to determine the most suitable filters for discrimination methods.The experimental results revealed that the three most adaptive filters of the pulse-coupled neural networks and ladder gradient methods are the wavelet,elliptic,and median filters and the elliptic,moving average,and wavelet filters,respectively. 展开更多
关键词 n-c Discrimination Pulse-shape discrimination ladder gradient Pulse-coupled neural network Filtering Filter adaptability
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