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The predictive value of NLR and SII in anti⁃MDA5 antibody⁃positive dermatomyositis with rapidly progressive interstitial lung disease
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作者 CAI Qingqing YOU Hanxiao +7 位作者 WANG Lei LÜChengyin SHI Yumeng QIU Yulu WU Lingyun WANG Fang ZHANG Miaojia TAN Wenfeng 《南京医科大学学报(自然科学版)》 北大核心 2025年第2期196-207,共12页
Objective:To evaluate the predictive value of the neutrophil⁃to⁃lymphocyte ratio(NLR)and the systemic immune⁃inflammation index(SII)in predicting patients with anti⁃melanoma differentiation⁃associated gene 5⁃positive(... Objective:To evaluate the predictive value of the neutrophil⁃to⁃lymphocyte ratio(NLR)and the systemic immune⁃inflammation index(SII)in predicting patients with anti⁃melanoma differentiation⁃associated gene 5⁃positive(anti⁃MDA5+)dermatomyositis(DM)develop into the rapidly progressive interstitial lung disease(RPILD).Methods:We retrospectively analyzed the clinical and laboratory data of 124 anti⁃MDA5+DM patients from the First Affiliated Hospital of Nanjing Medical University between March 2019 and September 2023.We identified independent risk factors associated with the development and mortality of RPILD with the Cox regression analysis,and determined the optimal cut⁃off values for predicting adverse outcomes with the receiver operating characteristic(ROC)curve analysis.Results:Among the 124 patients,36 patients(29.03%)developed RPILD,and 39 patients(31.45%)died during the follow⁃up period.The results of multivariate Cox regression analysis showed that the elevated NLR was an independent risk factor for RPILD development,while the elevated SII expression was independently associated with the increased mortality of RPILD.Based on the ROC curve analysis,NLR>6.12 was a predictor for RPILD,and SII>875.79 was associated with increased mortality risk of RPILD.Conclusion:Both NLR and SII are accessible,cost⁃effective,and reliable prognostic indicators for the prognosis of patients with anti⁃MDA5^(+)DM,providing a valuable guidance for clinical management and risk stratification of the disease. 展开更多
关键词 anti⁃melanoma differentiation⁃associated gene 5⁃positive dermatomyositis neutrophil⁃to⁃lymphocyte ratio rapidly pro⁃gressive interstitial lung disease systemic immune⁃inflammation index
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Distinct protein kinase C isozymes mediates inhibitory effects of different G-protein coupled receptors on cardiac rapidly activating delayed rectifier K ~ current
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《中国药理学通报》 CAS CSCD 北大核心 2015年第B11期165-166,共2页
Aim Evidence has shown that stimulation of alA-adrenorecetors receptor (alA-AR) or angiotensin II type 1 receptor (AT1R) acutely down-regulates the rapid component of the delayed rectifier K + current (IKr) via... Aim Evidence has shown that stimulation of alA-adrenorecetors receptor (alA-AR) or angiotensin II type 1 receptor (AT1R) acutely down-regulates the rapid component of the delayed rectifier K + current (IKr) via protein kinase C (PKC). This study was designed to investigate which PKC isozymes mediate down-regulations of IKr by alA-AR and AT1R. Method The whole-cell patch-clamp technique was used to record IKr in native cardio- myocytes and in human embryonic kidney (HEK) 293 cells co-transfected with human ether-a-go-go related gene (hERG) encoding α-subunit of IKr and human alA-AR or AT1R gene. Result In isolated guinea-pig ventricular cardiomyocytes the inhibitory action of Ang II on IKr was little affected by Go6976 (selectively inhibiting PKCα, β and γ) and Go6983 (selectively inhibiting PKCα, β, γ , δ, and ζ), but was significantly antagonized by an inter- nal dialysis with PKCe-selective inhibitory peptide εV1 -2. In contrast, the inhibitory action of alA-AR agonist A61603 on IKr was remarkably attenuated by Go6976 or Go6983, but not affected by peptide εV1 -2. Moreover, specific PKC-selective inhibitory peptide antagonized the effect of A61603. The results suggested that PKCe and PKCα isoform respectively mediated the inhibitory effect of AT1R and a1A-AR. In heterologous expression system, both PKCα and e-selective activator peptides down regulated hERG current with different manner. PKCα activator peptide shifted the activation curve of the channel to the right, but PKCe-selective activator peptide did not. Simi- larly, A61603 shifted the activation curve to the right, whereas Ang Ⅱ had no effect. In addition, both A61603 and PKCα activator peptide showed inhibitory action on bERG A PKC current (an bERG mutant in which 17 of the 18 ROSITE-predicted PKC acceptor serines/threonines were changed to alanine) with a similar potency to wild type bERG current. But, both Ang Ⅱ and PKCe-selective activator peptide exhibited no effects on bERG △ PKC cur- rent. The results indicated that PKCα and PKCe isoforms down-regulated bERG current through different mecha- nism. Conclusion PKCα and PKCe isoform respectively mediates the inhibition on IKr by stimulation of AT1R and alA-AR via different molecular mechanism. 展开更多
关键词 rapidly ACTIVATING delayed rectifier K + CURRENT protein KINASE C AT1R alA-AR
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SECOND PHASES OF RAPIDLY SOLIDIFIED AlFeCrZrVSi ALLOY AND THEIR THERMAL STABILITIES 被引量:4
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作者 Xiao Yude Li Songrui Li Wenxian Zeng Zhihua Ma Zhengqing(Department of Materials Science and Engineering,Central South University of Technology, Changsha 410083, China) 《Journal of Central South University》 SCIE EI CAS 1998年第1期24-27,共4页
The rapidly solidified powder of AlFeCrZrVSi aluminum alloy was prepared using multistage atomization and consolidated by hotextrusion, the evolution of microstructure of the extruded materials during thermal exposure... The rapidly solidified powder of AlFeCrZrVSi aluminum alloy was prepared using multistage atomization and consolidated by hotextrusion, the evolution of microstructure of the extruded materials during thermal exposure was studied with optical microscope, Xray diffraction and transmission electron microscope(TEM). The results show that the majority of dispersions present in the asextruded alloy are metastable Al12(Fe, Cr, V)3Si, which has excellent thermaldynamical stability and coarsening resistance; the coarsening ratecontrolling process of the Al12(Fe, Cr, V)3Si phase is considered to be diffusion of Fe atom along grain boundaries instead of bulk diffusion of Fe atom. 展开更多
关键词 aluminum ALLOY rapid SOLIDIFICATION THERMAL stability
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Effects of Fertilizing Materials on Rapidly Available-N in Black Soil in Songnen Plain
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作者 WangHongyan PengChi 《Journal of Northeast Agricultural University(English Edition)》 CAS 1996年第2期110-116,共7页
The analyses on the mathematical models of the long- term location test in black soil in Song-nen Plain shows that farm manure and chemical fertilizers make great contribution to rapidly available-N in soil, while sta... The analyses on the mathematical models of the long- term location test in black soil in Song-nen Plain shows that farm manure and chemical fertilizers make great contribution to rapidly available-N in soil, while stalk makes less contribution. The most optimal pattern of fertilizing materials is 28 t / ha of farm manure, 630 kg / ha chemical fertilizers and 2.41 / ha of stalk. 展开更多
关键词 fertilizing materials farm manure chemical fertilizers stalk rapidly available-N model
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Devitrification behaviour of rapidly solidified Al_87Ni_7Cu_3Nd_3 amorphous alloy prepared by melt spinning method 被引量:2
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作者 肖于德 李敏 +2 位作者 钟掘 黎文献 马正青 《Journal of Central South University of Technology》 EI 2007年第3期285-290,共6页
Rapidly solidified Al87Ni7Cu3Nd3 amorphous alloy was prepared by using melt spinning. Its calorimetric behavior was characterized by using differential scanning calorimeter in a continuous or isothermal heating mode. ... Rapidly solidified Al87Ni7Cu3Nd3 amorphous alloy was prepared by using melt spinning. Its calorimetric behavior was characterized by using differential scanning calorimeter in a continuous or isothermal heating mode. phase transformation was investigated, with a special interest in primary crystallization, by using an in-situ examination of X-ray diffractometry (XRD) and high resolution transmission electron microscopy (HRTEM). The results show that, the whole devitrification of rapidly solidified Al87NiyCu3Nd3 amorphous alloy involves two main processes of primary crystallization and secondary crystallization that consist mainly of two reactions. For primary crystallization, the apparent activation energies, EIso and EKis and growth activation energies Eg are about 153, 166 and 288 kJ/mol, respectively. The interdiffusion of Al atoms is a rate-controlled step of formation of the a(Al) particles, but slow diffusion of Ni and Nd atoms plays a significant role in retarding growth of the α (Al) particles. For secondary crystallization, EIso, EKis and Eg of the first reaction are about 291,208 and 290 kJ/mol, and those of the second reaction are about 367, 269 and 372 kJ/mol. The two reactions of secondary crystallization are controlled mainly in an interface-controlled three-dimensional mode, depending mainly on slow diffusion of Ni and Nd atoms. 展开更多
关键词 rapid solidification Al-rich amorphous alloy CRYSTALLIZATION nucleation and growth
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Devitrification process in rapidly solidified Al-Ni-Cu-Nd metallic glass
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作者 肖于德 黎文献 +3 位作者 D.Jacovkis N.Clavaguera M.T.Clavaguera-Mora J.Rodriguez-Viejo 《Journal of Central South University of Technology》 EI 2003年第3期163-167,共5页
In the present study, rapidly solidified ribbons of Al87 Ni7Cu3 Nd3 metallic glass was prepared by usingmelt spinning. Devitrification process of the totally amorphous ribbons was investigated by high temperature X-ra... In the present study, rapidly solidified ribbons of Al87 Ni7Cu3 Nd3 metallic glass was prepared by usingmelt spinning. Devitrification process of the totally amorphous ribbons was investigated by high temperature X-raydiffraction analysis, combining with differential scanning calorimetry, under continuous and isothermal heating re-gime. The X-ray diffraction intensity and full width at the half maximum (FWHM) were analyzed to investigate theincrease of crystallized amount and growth of α-Al crystal particles. The results show that under continuous heatingregime, the metallic glass devitrifies via two main stages: primary crystallization, resulting in two-phase mixture ofα-Al plus residual amorphous phase, and secondary crystallization, corresponding to rapid precipitation of some in-ter-metallic phases in the form of dispersion or eutectic mixture. Under isothermal heating regime, only Al crystalprecipitates from the Al-rich amorphous matrix at low temperature, and when heating at 280 ℃ only Al crystal pre-cipitates within a short time, and then Al8 Cu4 Nd forms, followed by Al3 Ni, in the residual amorphous phase. Whenheating at higher temperature or for longer time, Aln Nd3 forms, the amorphous phase disappears, and the ribbonsdevelop into polycrystalline morphologies with multiply phase mixture of a-Al, Al8 Cu4 Nd, Al3 Ni, and Al11 Nd3. 展开更多
关键词 rapid SOLIDIFICATION Al-rich AMORPHOUS alloy DEVITRIFICATION process phase TRANSFORMATION
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Status and Development of Rapid Detection Technology for Tunnel Structural Defects 被引量:3
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作者 LIU Xuezeng FANG Maoliu +3 位作者 WU Dexing LI Yinping LIU Xingen LI Gang 《隧道建设(中英文)》 北大核心 2025年第4期657-676,I0005-I0024,共40页
Based on inspection data,the authors analyze and summarize the main types and distribution characteristics of tunnel structural defects.These defects are classified into three types:surface defects,internal defects,an... Based on inspection data,the authors analyze and summarize the main types and distribution characteristics of tunnel structural defects.These defects are classified into three types:surface defects,internal defects,and defects behind the structure.To address the need for rapid detection of different defect types,the current state of rapid detection technologies and equipment,both domestically and internationally,is systematically reviewed.The research reveals that surface defect detection technologies and equipment have developed rapidly in recent years.Notably,the integration of machine vision and laser scanning technologies have significantly improved detection efficiency and accuracy,achieving crack detection precision of up to 0.1 mm.However,the non-contact rapid detection of internal and behind-the-structure defects remains constrained by hardware limitations,with traditional detection remaining dominant.Nevertheless,phased array radar,ultrasonic,and acoustic vibration detection technologies have become research hotspots in recent years,offering promising directions for detecting these challenging defect types.Additionally,the application of multisensor fusion technology in rapid detection equipment has further enhanced detection capabilities.Devices such as cameras,3D laser scanners,infrared thermal imagers,and radar demonstrate significant advantages in rapid detection.Future research in tunnel inspection should prioritize breakthroughs in rapid detection technologies for internal and behind-the-structure defects.Efforts should also focus on developing multifunctional integrated detection vehicles that can simultaneously inspect both surface and internal structures.Furthermore,progress in fully automated,intelligent systems with precise defect identification and real-time reporting will be essential to significantly improve the efficiency and accuracy of tunnel inspection. 展开更多
关键词 TUNNEL structural defect inspection techniques inspection equipment rapid inspection
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氨燃料发动机腐蚀损伤激光超声Lamb波检测改进
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作者 孙小广 万若楠 余光正 《激光与红外》 北大核心 2025年第2期233-238,共6页
当前激光超声Lamb波在氨燃料发动机表面进行无损检测时,频散较为严重,存在多模态现象,使得信号复杂,不能完全消除频散效应一直是该领域的难题。提出基于激光超声Lamb波的氨燃料发动机腐蚀损伤检测改进方法。激光激励与接收捕获氨燃料发... 当前激光超声Lamb波在氨燃料发动机表面进行无损检测时,频散较为严重,存在多模态现象,使得信号复杂,不能完全消除频散效应一直是该领域的难题。提出基于激光超声Lamb波的氨燃料发动机腐蚀损伤检测改进方法。激光激励与接收捕获氨燃料发动机上的一维激光超声Lamb波信号的同时,引入一种线性映射频散补偿法,对信号中的频散效应实施有效修正;通过短空间二维傅里叶变换得到特定中心频率下信号的频率、波数及空间位置信息的幅值-空间-波数谱,判断氨燃料发动机在扫描路径上的腐蚀损伤大概位置;根据信号特征,采用RAPID方法确定发动机腐蚀损伤的精确位置,实现腐蚀损伤检测。实验结果表明:经所提方法补偿后,信号波形显著改善,时域紧凑,频域特征清晰,并且所提方法能够有效提高氨燃料发动机腐蚀损伤检测的精度和可靠性。 展开更多
关键词 激光超声Lamb波 线性映射频散补偿 信号特征识别 RAPID 腐蚀损伤检测
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病情活动性指标ASDAS、RAPID3和BASDAI在判断强直性脊柱炎患者疾病活动度中的比较 被引量:25
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作者 宋婧 周凌 +2 位作者 陈凌 吴歆 徐沪济 《第二军医大学学报》 CAS CSCD 北大核心 2015年第8期909-913,共5页
目的研究ASDAS和RAPID3对强直性脊柱炎(ankylosing spondylitis,AS)患者疾病活动度的判断价值。方法对82例AS患者进行问卷调查,统计其一般情况、病情活动度指标,抽取静脉血测定红细胞沉降率(erythrocyte sedimentation rate,ESR)和C反... 目的研究ASDAS和RAPID3对强直性脊柱炎(ankylosing spondylitis,AS)患者疾病活动度的判断价值。方法对82例AS患者进行问卷调查,统计其一般情况、病情活动度指标,抽取静脉血测定红细胞沉降率(erythrocyte sedimentation rate,ESR)和C反应蛋白(C-reactive protein,CRP)水平。通过相关性分析、kappa一致性检验比较传统方法 Bath强直性脊柱炎病情活动性指数(BASDAI)与新型方法ASDAS、RAPID3对疾病活动度的评估价值。结果 ASDAS-CRP与RAPID3具有较好的一致性(kappa值:0.788),而这两者与BASDAI的一致性检验结果不理想(kappa值:0.342,0.367)。BASDAI、ASDAS、RAPID3与医生总体评价(DOCGL)、患者自身评价(PATGL)均具有良好的相关性,其中ASDAS、RAPID3与DOCGL、PATGL的相关性明显强于BASDAI与DOCGL、PATGL的相关性(ASDAS-CRP、ASDAS-ESR、RAPID3、BASDAI与DOCGL的相关性分析r值分别为0.684、0.720、0.642及0.576;与PATGL的相关性分析r值分别为0.822、0.816、0.851及0.725)。结论 ASDAS对AS疾病活动的评估能力优于BASDAI,是理想的评价疾病活动度的新指标,值得推广应用;RAPID3具有方便、简洁、不受实验室检查结果限制的特点,在评价AS活动度时同样具有良好的可靠性及有效性。 展开更多
关键词 强直性脊柱炎 BASDAI ASDAS RAPID3
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RAPID软件在急性缺血性脑卒中血管内治疗患者预后预测中的应用价值 被引量:22
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作者 张萍 张敏敏 +4 位作者 杨鹏飞 陆建平 刘建民 张永巍 邓本强 《第二军医大学学报》 CAS CSCD 北大核心 2018年第9期1013-1018,共6页
日的探讨基于脑计算机断层扫描灌注成像(CTP)的RAPID软件在行血管内治疗的前循环急性缺血性脑卒中患者预后预测中的应用价值,并探寻影响患者预后的指标。方法回顾性分析2017年1月至2018年2月于海军军医大学(第二军医大学)长海医院行血... 日的探讨基于脑计算机断层扫描灌注成像(CTP)的RAPID软件在行血管内治疗的前循环急性缺血性脑卒中患者预后预测中的应用价值,并探寻影响患者预后的指标。方法回顾性分析2017年1月至2018年2月于海军军医大学(第二军医大学)长海医院行血管内治疗,完成脑CTP检查及RAPID软件进行后期图像分析,且术后血管再通达改良脑梗死溶栓(mTICI)2b级及以上的前循环急性缺血性脑卒中患者的病历资料。根据术后3个月改良Rankin量表(mRS)评分,将患者分为预后良好组(mRS评分≤2分)和预后不良组(mRS评分>2分)。比较两组年龄、入院时美国国立卫生研究院卒中量表(NIHSS)评分等一般资料以及RAPID软件分析结果,包括达峰时间>4s、>6s、>8s、>10s的低灌注区体积(V_(Tmax>4s)、V_(Tmax>6s)、V_(Tmax>8s)、V_(Tmax>10s))和梗死核心区体积(V_(CBF<30%))、脑血流不匹配体积和不匹配指数(MMR)。采用多因素logistic回归分析筛选预测因素,并获得预测公式。采用受试者工作特征(ROC)曲线评价该预测公式的预测能力。结果符合入组标准的前循环急性缺血性脑卒中患者共137例,预后良好组92例,预后不良组45例。预后良好组患者的年龄、入院时NIHSS评分均低于预后不良组,差异均有统计学意义(t=-4.21、-4.06,P均<0.01)。预后良好组V_(Tmax>6s_、V_(Tmax>8s_、V_(Tmax>10s)、V_(CBF<30%)均小于预后不良组,MMR大于预后不良组,差异均有统计学意义(Z=-3.11、-3.17、-3.38、-4.52、-3.74,P均<0.01)。Logistic回归分析显示年龄、V_(CBF<30%)小是大血管闭塞所致前循环急性缺血性脑卒中血管内治疗患者预后良好的影响因素[比值比(OR)=0.904,95%置信区间(CI):0.860~0.950;OR=0.976,95%CI:0.964~0.988;P均<0.01]。预测公式为Logit(P)=8.454-0.024×V_(CBF<30%)-0.101×年龄。ROC曲线分析结果显示该预测公式的曲线下面积为0.786(95%CI:0.699~0.873,P<0.01)。结论 V_(CBF<30%)和年龄是前循环急性缺血性脑卒中血管内治疗患者预后的独立预测因素,年龄越小、V_(CBF<30%)越小预后良好的可能越大。基于CTP的RAPID软件可用于术前筛选适合血管内治疗的前循环急性缺血性脑卒中患者,值得临床推广。 展开更多
关键词 计算机断层扫描灌注成像 RAPID软件 血管内治疗 缺血性脑卒中 预后
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灯盏花chi的克隆及其生物信息学分析 被引量:11
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作者 刘春霞 王玥 +4 位作者 崔明昆 严胜柒 谢庆华 官会林 张云峰 《武汉植物学研究》 CAS CSCD 北大核心 2010年第6期682-690,共9页
查尔酮异构酶(CHI)是调控黄酮生物合成的关键酶,分离和克隆这一酶的功能基因,对利用转基因技术进行灯盏花黄酮生物合成的调控具有重要意义。本研究采用RT-PCR和RACE技术,获得了chi cDNA全序列,GenBank登录号为GU208823.1,序列全长996 bp... 查尔酮异构酶(CHI)是调控黄酮生物合成的关键酶,分离和克隆这一酶的功能基因,对利用转基因技术进行灯盏花黄酮生物合成的调控具有重要意义。本研究采用RT-PCR和RACE技术,获得了chi cDNA全序列,GenBank登录号为GU208823.1,序列全长996 bp,开放阅读框为594 bp,编码197个氨基酸,3-Race有一个多聚腺苷酸加尾信号。应用软件预测该基因编码蛋白分子量约为21.6 kD,理论等电点为4.78。该基因编码的蛋白无跨膜结构域,其二级结构的主要构件为α-螺旋和随机卷曲。对其三级结构进行了建模,表明其结构与苜蓿chi的三级结构相似。同时根据灯盏花chi N端序列变化的特征,提出了灯盏乙素的合成可能与chi在细胞亚结构的定位及其与合成代谢相关酶形成复合酶的特异性有关。研究为利用基因工程定向改变灯盏花黄酮代谢产物奠定了基础。 展开更多
关键词 灯盏花 查尔酮异构酶(CHI) RT-PCR(Polymerase Chain Reaction) RACE(Rapid AMPLIFICATION of cDNA Ends) 序列分析
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Multisim在超导器件研究中的应用 被引量:10
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作者 樊彬 周铁戈 +3 位作者 阎少林 岳宏卫 王争 宋凤斌 《电子学报》 EI CAS CSCD 北大核心 2010年第8期1886-1891,共6页
为了对约瑟夫森结及其相关电路进行仿真研究,首次在Multisim中建立了约瑟夫森结的模型.利用Multisim对直流约瑟夫森效应,交流约瑟夫森效应进行了仿真验证.随后利用在Multisim中建立的模型对电阻电容电感并联约瑟夫森结(Resistively-Capa... 为了对约瑟夫森结及其相关电路进行仿真研究,首次在Multisim中建立了约瑟夫森结的模型.利用Multisim对直流约瑟夫森效应,交流约瑟夫森效应进行了仿真验证.随后利用在Multisim中建立的模型对电阻电容电感并联约瑟夫森结(Resistively-Capacitively-Inductively Shunted Junction,RCLSJ)模型中的混沌行为,微波感应台阶,热噪声对台阶的影响以及RSFQ(Rapid Single Flux Quantum)电路进行了仿真研究.仿真结果证明了在Multisim中建立的模型对超导器件进行仿真研究是合理可行的,这对超导器件的分析和设计具有重要意义. 展开更多
关键词 MULTISIM 约瑟夫森结 混沌行为 微波感应台阶 RSFQ(Rapid Single FLUX Quantum)电路
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阿尔金淡水泉早古生代泥质高压麻粒岩及其P-T演化轨迹 被引量:39
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作者 曹玉亭 刘良 +2 位作者 王超 陈丹玲 张安达 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第9期2260-2270,共11页
南阿尔金构造带淡水泉一带出露的含石榴石蓝晶石黑云母片麻岩是一套典型的泥质高压麻粒岩,其峰期特征矿物组合为石榴子石+蓝晶石+钾长石+金红石+石英。根据矿物内部一致性热力学数据和Thermocalc 3.23程序计算,确定其峰期变质温压条件为... 南阿尔金构造带淡水泉一带出露的含石榴石蓝晶石黑云母片麻岩是一套典型的泥质高压麻粒岩,其峰期特征矿物组合为石榴子石+蓝晶石+钾长石+金红石+石英。根据矿物内部一致性热力学数据和Thermocalc 3.23程序计算,确定其峰期变质温压条件为T>850℃和P>11kbar。结合岩相学研究和P-T视剖面图计算,可识别出该岩石经历了4个阶段的变质演化,构成了一个早期快速等温降压,后期近等压降温的顺时针型的退变质P-T演化轨迹,为与陆壳俯冲碰撞有关的高压变质事件的产物。该岩石锆石阴极发光图像显示其内部具有明显的核-边结构,核部为残留的原岩碎屑锆石,边部则表现为面状或扇状生长的变质锆石的特征。微区原位LA-ICP-Ms微量元素分析表明,核部测点的重稀土含量较高,对应Th/U接近于0.4,具有岩浆锆石的特征;边部测点的重稀土相对亏损,重稀土配分曲线平坦,对应Th/U比值均小于0.1,显示与石榴子石平衡共生的变质锆石特征。LA-ICP-MS微区定年获得其变质年龄为486±5Ma,该年龄值与阿尔金江尕勒萨依和英格利萨依两地超高压变质岩石的变质年龄相近,进一步证明沿阿尔金构造带南缘断续存在一条早古生代的高压-超高压变质岩带。另外,本次研究在获得该泥质高压麻粒岩峰期变质时代的同时,还获得该岩石原岩的形成时代上限值约为719Ma,从而限定阿尔金构造带南缘阿尔金群的形成时代可能不属古元古代,而应属新元古代。 展开更多
关键词 阿尔金 淡水 早古生代 泥质高压麻粒岩 演化轨迹 Altyn Tagh area 超高压变质岩石 metamorphic age 变质锆石 构造带 mineral assemblage internal structure pelitic GRANULITE 形成时代 特征 石榴子石 峰期变质温压条件 变质年龄 rapid EXHUMATION
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基于包围盒和空间分割的混合碰撞检测算法 被引量:17
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作者 沈学利 吴琼 《计算机工程》 CAS CSCD 2012年第6期256-258,共3页
针对碰撞检测算法实时性较差的缺陷,提出基于层次包围盒和空间分割的混合碰撞检测算法。该算法采用构造对象的AABB包围盒,快速排除不可能相交的对象进行空间分割,实现虚拟环境对象的碰撞检测。实验结果表明,与经典的Rapid算法对比,该算... 针对碰撞检测算法实时性较差的缺陷,提出基于层次包围盒和空间分割的混合碰撞检测算法。该算法采用构造对象的AABB包围盒,快速排除不可能相交的对象进行空间分割,实现虚拟环境对象的碰撞检测。实验结果表明,与经典的Rapid算法对比,该算法能够节省检测时间,提高碰撞检测的效率。 展开更多
关键词 虚拟现实 包围盒 空间分割 混合碰撞检测 AABB包围盒 Rapid算法
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遥感影像判读地类在贵州省林地变更调查中的应用 被引量:12
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作者 李涛 谭伟 +1 位作者 王六平 杨健 《贵州农业科学》 CAS 北大核心 2013年第9期172-175,F0002,共5页
为了切实做好贵州省林地变更调查工作,提高林地变更调查中各类土地类型的检测精度和确保林地资源数据的时效性,在处理的Rapid-Eye遥感影像基础上建立贵州省遥感判断地类区划图斑标志卡,进行贵州省林地变更遥感地类判读研究。结果表明:运... 为了切实做好贵州省林地变更调查工作,提高林地变更调查中各类土地类型的检测精度和确保林地资源数据的时效性,在处理的Rapid-Eye遥感影像基础上建立贵州省遥感判断地类区划图斑标志卡,进行贵州省林地变更遥感地类判读研究。结果表明:运用Rapid-Eye遥感影像进行贵州省林地变更遥感地类判读是可行的。贵州省有林地、非林地的个数判读精度达98%,其次是灌木林地和其他非林地,判读个数精度都达96%,无立木林地判读达94%。利用ArcGIS9.3建立遥感样地属性数据库,提高了林地变更地类调查的质量和效率,为实现全省林业资源的动态管理提供了理论基础。 展开更多
关键词 林地变更调查 Rapid—Eye 遥感判读 图斑标志卡 数据库
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基于RapidEye影像的农村居民地遥感监测--以江西省泰和县为例 被引量:3
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作者 高孟绪 王卷乐 +1 位作者 柏中强 祝俊祥 《国土资源遥感》 CSCD 北大核心 2016年第1期130-135,共6页
农村居民地遥感信息获取对于监测农村居民地时空变化、服务"三农"和国土资源管理具有重要意义。以Rapid Eye卫星影像数据为数据源,江西省泰和县为研究区,利用最大似然法进行居民地等土地覆盖类别的分类提取与精度评价及分析... 农村居民地遥感信息获取对于监测农村居民地时空变化、服务"三农"和国土资源管理具有重要意义。以Rapid Eye卫星影像数据为数据源,江西省泰和县为研究区,利用最大似然法进行居民地等土地覆盖类别的分类提取与精度评价及分析。结果表明:分类总体精度达到84.33%,其中农村居民地的制图精度和用户精度分别为76.01%和82.28%,与第二次全国土地调查中的居民地数据对比,其一致性达到71.0%。结合实地验证,对本分类精度的误差原因进行分析。本研究表明利用5 m分辨率的Rapid Eye影像进行县级农村居民地监测是可行的,可为后续同类研究提供技术参考。 展开更多
关键词 农村居民地 RAPID Eye影像 遥感分类 遥感解译 泰和县
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国际图像系统(I^2S)上手写汉字识别研究 被引量:3
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作者 王林泉 邱伟峰 《计算机工程》 CAS CSCD 北大核心 1994年第5期38-40,共3页
提出一种用Rapid算法对手写汉字进行识别.它是在国际图像系统上实现的.文字图像经摄像机输入,预处理时采用锐化边界法.使图像边界清晰.文字图像经正规化后,进行Rapid变换,抽取识别特征,特征抽取能比较好地吸收手写汉... 提出一种用Rapid算法对手写汉字进行识别.它是在国际图像系统上实现的.文字图像经摄像机输入,预处理时采用锐化边界法.使图像边界清晰.文字图像经正规化后,进行Rapid变换,抽取识别特征,特征抽取能比较好地吸收手写汉字变形和扭曲,提高识别率.计算机实验表明,本算法对手写汉字识别是比较有效的. 展开更多
关键词 汉字识别 国际图像系统 Rapid算法
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一种基于高阶统计量的图像识别算法研究 被引量:1
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作者 李军宏 潘泉 +1 位作者 程咏梅 崔培玲 《系统工程与电子技术》 EI CSCD 北大核心 2005年第6期978-982,1033,共6页
提出了一种基于图像高阶统计量的识别算法。利用Radon变换将图像数据变换到一维空间,通过计算投影数据的双谱构造出具有比例和平移不变性的特征。利用Rapid变换获得特征的旋转不变特性;接着,利用阈值分析的方法进行特征选择,获得了较原... 提出了一种基于图像高阶统计量的识别算法。利用Radon变换将图像数据变换到一维空间,通过计算投影数据的双谱构造出具有比例和平移不变性的特征。利用Rapid变换获得特征的旋转不变特性;接着,利用阈值分析的方法进行特征选择,获得了较原始特征更好的识别效果。针对特征向量过长的问题,利用主元分析进行长度压缩。与不同方法的实验比较表明,算法能够有效地用于图像识别。 展开更多
关键词 高阶统计量 Rapid变换 阈值分析 主元分析
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快速凝固Cu-Zn-Al-Mn-Ni-Ti合金的显微组织
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作者 常凤莲 苏华钦 +2 位作者 王世栋 张谨平 梅建平 《东南大学学报(自然科学版)》 EI CAS CSCD 1995年第A04期154-158,共5页
快速凝固Cu-Zn-Al-Mn-Ni-Ti合金的显微组织常凤莲,苏华钦王世栋,张谨平,梅建平(东南大学机械工程系,南京210018)(东南大学分析测试中心,南京210018)晶粒细化是目前Cu基记忆合金研究焦点之一。... 快速凝固Cu-Zn-Al-Mn-Ni-Ti合金的显微组织常凤莲,苏华钦王世栋,张谨平,梅建平(东南大学机械工程系,南京210018)(东南大学分析测试中心,南京210018)晶粒细化是目前Cu基记忆合金研究焦点之一。快速凝固技术应用于制备Cu基记忆合... 展开更多
关键词 RAPID SOLIDIFICATION DISLOCATION microstructure SECOND phase
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阴离子杂质对KDP晶体生长习性的影响及快速生长研究
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作者 傅有君 王圣来 +5 位作者 孙洵 李毅平 曾红 罗建平 段爱东 高樟寿 《人工晶体学报》 EI CAS CSCD 北大核心 2000年第S1期102-,共1页
Great interest is being focused on the growth technique of KDP crystal,the first choice material for the fabrication of frequency converter and electro optic switcher used in the studies of inertial confinement fusion... Great interest is being focused on the growth technique of KDP crystal,the first choice material for the fabrication of frequency converter and electro optic switcher used in the studies of inertial confinement fusion (ICF).To reduce the cost of growth,scientists are endeavoring to promote the growth rate.The“point seed” method is one of rapid growth techniques recently developed by Lawrence Livermore National Laboratory.In the former technique,crystals are grown in all three directions at an averaged rate of 10 15mm/day. Impurities are regarded as one of the factors to inhibit the growth rate.It is generally accepted that high valence cationic ions,such as Fe 3+ ,Cr 3+ ,Al 3+ ,etc,are easy to be adsorbed on the prismatic faces and inhibit their growth.Some anions,especially those have ability to form strong hydra bond,such as phosphate derivatives (polyphosphate,metaphosphate,pyrophosphate,etc) have significant inhibiting effects on the growth of KDP pyramidal face.It is suggested that the H bonding is the key interaction force between the growing surface and the impurities. 展开更多
关键词 KDP crystal nonlinear optical crystal crystal growth from salution rapid growth
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