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Lower Bound of Distance Between Unitary Orbits of Normal Elements in C^(*)-algebras of Tracial Rank One
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作者 WANG Ruofei LUO Zheng 《数学进展》 北大核心 2026年第1期171-182,共12页
This paper studies certain estimates for the lower bound of distance between unitary orbits of normal elements.We show that the distance between unitary orbits of normal elements of simple C^(*)-algebras of tracial ra... This paper studies certain estimates for the lower bound of distance between unitary orbits of normal elements.We show that the distance between unitary orbits of normal elements of simple C^(*)-algebras of tracial rank no more than k has a lower bound.Furthermore,if k≤1 and normal elements are commuting,then the lower bound will be better.Another result establishes a connection involving the spectrum distance operator Dc between a C^(*)-algebra of stable rank one C^(*)-algebra and its hereditary C^(*)-subalgebra. 展开更多
关键词 unitary orbit hereditary C^(*)-subalgebra tracial rank one lower bound
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Contiguous orbital inflammation from paranasal sinus abnormalities in etiology of thyroid-associated ophthalmopathy
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作者 Xin-Xin Hao Yang-Xu Tao +2 位作者 Xiang Xu Ming-Ming Liu Yang Li 《International Journal of Ophthalmology(English edition)》 2026年第1期97-104,共8页
AIM:To define the prevalence and anatomical patterns of paranasal sinus abnormalities(PSA)in thyroid-associated ophthalmopathy(TAO)and to test the hypothesis that TAO is partially driven by contiguous orbital inflamma... AIM:To define the prevalence and anatomical patterns of paranasal sinus abnormalities(PSA)in thyroid-associated ophthalmopathy(TAO)and to test the hypothesis that TAO is partially driven by contiguous orbital inflammation rather than systemic autoimmunity or generalized orbital pressure.METHODS:Data included ophthalmic assessments and a panel of thyroid function and autoimmune biomarkers.Blinded radiological analysis of orbital computed tomography(CT)scans was performed to quantify sinus abnormalities and extraocular muscles(EOMs)involvement.Patients were categorized into two groups based on CT findings,those with no radiological evidence of sinus abnormalities(non-PSA control group)and those with identifiable PSA.Furthermore,ethmoid sinus mucosal biopsies from a subset of TAO patients and noninflammatory controls were subjected to histopathological analysis.RESULTS:Totally 121 TAO patients(mean age 42.4±12.8y,range 10-78y),male:female=42:79,were included.PSA was identified in 44.6%(n=54)of patients,with a distribution anatomically restricted to the maxillary(50.0%isolated)and ethmoid sinuses(18.5%isolated;29.6%combined).Compared to the non-PSA group(n=67),patients with PSA were significantly older(45.1±11.8 vs 40.3±13.2y;P=0.040)and were more likely to be male(55.6%vs 17.9%;P<0.001).They also had significantly higher proptosis(22.1±3.2 vs 20.7±2.9 mm;P<0.001).Medial/inferior rectus involvement was most frequent(88.4%vs 89.3%).Histopathological analysis of sinus mucosa from PSA patients provided direct evidence of pathology,revealing a dense,chronic lymphoplasmacytic infiltrate and submucosal edema,validating the radiological findings as a true inflammatory process.No significant correlation was found with systemic autoimmune markers,including thyroid-stimulating hormone(TSH)receptor antibodies(TRAb,median 4.86 vs 2.71 IU/L,P=0.104).CONCLUSION:TAO is associated with a high prevalence of PSA in a pattern consistent with the orbital anatomy.The correlation with ipsilateral muscle thickening combined with the lack of association with proptosis laterality or systemic biomarkers lend strong support to a model of contiguous inflammation over systemic autoimmunity,a hypothesis that warrants further validation through longitudinal and mechanistic studies. 展开更多
关键词 thyroid-associated ophthalmopathy paranasal sinus abnormalities PROPTOSIS orbital inflammation
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MMC-HVDC并网系统多模态频率漂移SSO机理分析
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作者 李柯 班潇凡 《自动化应用》 2025年第11期135-137,共3页
在风力发电的新型电力系统中,风力发电的波动性与模块化多电平换流器(MMC)内部动态特性的耦合作用,使得振荡在高压直流输电(HVDC)方式下传播扩散,导致风场波动场景下MMC-HVDC并网系统的次同步振荡(SSO)具有多模态频率漂移特性。基于风... 在风力发电的新型电力系统中,风力发电的波动性与模块化多电平换流器(MMC)内部动态特性的耦合作用,使得振荡在高压直流输电(HVDC)方式下传播扩散,导致风场波动场景下MMC-HVDC并网系统的次同步振荡(SSO)具有多模态频率漂移特性。基于风力发电随机性与MMC内部动态特性的MMC-HVDC等值小信号动态模型,以特征值分析探究送受端MMC的多模态频率漂移SSO机理,优选出影响SSO模态的主要变量及相关电气参数。 展开更多
关键词 MMC sso 小信号动态模型 多模态频率漂移
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幼儿园教师付出—回报失衡感表征、行为选择及平衡重构——基于SSO因果模型
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作者 李杨 贺敬雯 《河南科技学院学报(社会科学版)》 2025年第4期65-76,共12页
为探究幼儿园教师付出—回报失衡感的产生原因、类型与失衡后的行为选择,基于扎根理论,以14位幼儿园教师为研究对象,并结合SSO因果模型构建幼儿园教师付出—回报失衡感框架。结果表明,幼儿园教师付出—回报失衡感具有多重性和层次性,其... 为探究幼儿园教师付出—回报失衡感的产生原因、类型与失衡后的行为选择,基于扎根理论,以14位幼儿园教师为研究对象,并结合SSO因果模型构建幼儿园教师付出—回报失衡感框架。结果表明,幼儿园教师付出—回报失衡感具有多重性和层次性,其失衡感可分为物质回报失衡、情感回报失衡、职业稳定回报失衡三类。其中,由工作负担加剧、组织分配不均触发的幼儿园教师物质回报失衡是首要“着力点”,由人际关系紧张、家长理解偏颇构成的幼儿园教师情感回报失衡是间接“催化剂”,由职业稳定性不足、发展空间受限导致的幼儿园教师职业稳定回报失衡是最终“助推器”。在失衡的压力下,幼儿园教师利用已有的资源进行平衡重构,从而产生坚守初心、循环上升、工作退缩、无奈离职四种行为选择。为此,应从改善园所薪资待遇,缓解幼儿园教师物质失衡;增强园所内部支持,调和幼儿园教师情感失衡;主动寻求发展机会,减少幼儿园教师稳定失衡三方面着手,以改善幼儿园教师付出—回报的失衡感,不断增强幼儿园教师的职业归属感与情感韧性。 展开更多
关键词 幼儿园教师 付出—回报失衡感 扎根理论 sso模型 情感韧性
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Factors Associated with Complications of Acute Bacterial Rhinosinusitis in Children
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作者 Amadou Njifou Njimah Louise Mouangue-Mbonjo +3 位作者 Patricia Epée Eboumbou Daniele-Christiane Kedy Mangamba Koum François Djomou Louis Richard Njock 《International Journal of Otolaryngology and Head & Neck Surgery》 2025年第1期57-67,共11页
Background: In children, acute bacterial rhinosinusitis (ABRS) is often complicated by ophthalmological and/or neurological involvement. These complications should be known and recognized, as they require urgent treat... Background: In children, acute bacterial rhinosinusitis (ABRS) is often complicated by ophthalmological and/or neurological involvement. These complications should be known and recognized, as they require urgent treatment with intravenous antibiotics and close in-hospital monitoring. In this study, we aimed to identify the main risk factors associated with the development of complications in children aged 2 - 17 years with ABRS. Methods: We conducted a retrospective cohort study of patients with ABRS complications in a primary hospital. Participants were divided into two groups: the control group comprising patients without complications (Group 1, n = 82) and the study group comprising patients with complications requiring hospitalization (Group 2, n = 41). We assessed the sociodemographic, clinical, and imaging data of both groups. Using multivariate logistic regression, we assessed risk factors of ABRS complications. Results: No socio-demographic characteristics were associated with ABRS complications (p ≥ 0.05). Factors associated with complications were delay in consultation (t = 5.282;p Conclusions: Intracranial and extracranial complications of ABRS in children have become rare in our setting. These complications can be serious and potentially fatal. Risk factors of these complications are delays in consultation, the presence of ophthalmological signs, and more than one affected sinus. Controlling modifiable factors would improve the treatment success of ABRS complications in children. 展开更多
关键词 RHINOSINUSITIS Orbital Complications Endocranial Complications Imaging Children SURGERY
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BRAKE ORBITS WITH MINIMAL PERIOD ESTIMATES OF FIRST-ORDER ANISOTROPIC HAMILTONIAN SYSTEMS
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作者 Xiaofei ZHANG Chungen LIU 《Acta Mathematica Scientia》 2025年第2期347-362,共16页
In this paper,the problem of brake orbits with minimal period estimates are considered for the first-order Hamiltonian systems with anisotropic growth,i.e.,the Hamiltonian functions may have super-quadratic,sub-quadra... In this paper,the problem of brake orbits with minimal period estimates are considered for the first-order Hamiltonian systems with anisotropic growth,i.e.,the Hamiltonian functions may have super-quadratic,sub-quadratic and quadratic behaviors simultaneously in different variable components. 展开更多
关键词 Hamiltonian system anisotropic growth brake orbit Lo-index
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Birkhoff Orbits for Twist Homeomorphisms on the High-Dimensional Cylinder
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作者 ZHOU Tong 《Wuhan University Journal of Natural Sciences》 2025年第1期43-48,共6页
It is known that monotone recurrence relations can induce a class of twist homeomorphisms on the high-dimensional cylinder,which is an extension of the class of monotone twist maps on the annulus or two-dimensional cy... It is known that monotone recurrence relations can induce a class of twist homeomorphisms on the high-dimensional cylinder,which is an extension of the class of monotone twist maps on the annulus or two-dimensional cylinder.By constructing a bounded solution of the monotone recurrence relation,the main conclusion in this paper is acquired:The induced homeomorphism has Birkhoff orbits provided there is a compact forward-invariant set.Therefore,it generalizes Angenent's results in low-dimensional cases. 展开更多
关键词 monotone recurrence relation twist homeomorphism high-dimensional cylinder bounded action Birkhoff orbit
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Data matching and association based on the arc-segment difference method
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作者 Jiannan Sun Zhe Kang +1 位作者 Zhenwei Li Cunbo Fan 《Astronomical Techniques and Instruments》 2025年第5期299-309,共11页
In response to the issue of fuzzy matching and association when optical observation data are matched with the orbital elements in a catalog database,this paper proposes a matching and association strategy based on the... In response to the issue of fuzzy matching and association when optical observation data are matched with the orbital elements in a catalog database,this paper proposes a matching and association strategy based on the arcsegment difference method.First,a matching error threshold is set to match the observation data with the known catalog database.Second,the matching results for the same day are sorted on the basis of target identity and observation residuals.Different matching error thresholds and arc-segment dynamic association thresholds are then applied to categorize the observation residuals of the same target across different arc-segments,yielding matching results under various thresholds.Finally,the orbital residual is computed through orbit determination(OD),and the positional error is derived by comparing the OD results with the orbit track from the catalog database.The appropriate matching error threshold is then selected on the basis of these results,leading to the final matching and association of the fuzzy correlation data.Experimental results showed that the correct matching rate for data arc-segments is 92.34% when the matching error threshold is set to 720″,with the arc-segment difference method processing the results of an average matching rate of 97.62% within 8 days.The remaining 5.28% of the fuzzy correlation data are correctly matched and associated,enabling identification of orbital maneuver targets through further processing and analysis.This method substantially enhances the efficiency and accuracy of space target cataloging,offering robust technical support for dynamic maintenance of the space target database. 展开更多
关键词 Optical data processing Space target identification Fuzzy correlation Arc-segment difference method Orbit determination
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Highly N_(2) dissociation catalyst:Ir(100) and Ir(110) surfaces
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作者 Chaozheng He Menghui Xi +3 位作者 Chenxu Zhao Ran Wang Ling Fu Jinrong Huo 《Chinese Chemical Letters》 2025年第3期526-531,共6页
Density functional theory(DFT)was performed to systematically study the adsorption and dissociation of N_(2)on Ir(100)and Ir(110)surfaces.By analyzing the properties,including adsorption energies,reaction barriers,and... Density functional theory(DFT)was performed to systematically study the adsorption and dissociation of N_(2)on Ir(100)and Ir(110)surfaces.By analyzing the properties,including adsorption energies,reaction barriers,and optimal adsorption sites,the hollow(H)sites were finally identified as favorable dissociation sites for N_(2).The dissociation barriers of N_(2)are 0.87eV on Ir(100)and 1.12eV on Ir(110),which can be overcome at around 348 and 448 K,respectively.Therefore,Ir(100)is screened as a promising catalyst for N_(2)dissociation compared to Ir(110).This can be attributed to the significantly higher adsorption energy of N_(2)on the H site of Ir(100)(−0.48 eV)compared to that on Ir(110)(−0.22 eV),leading to different dissociation mechanisms on Ir(100)and Ir(110).Ir(100)can dissociate N_(2)directly on H site and Ir(110)should firstly capture N_(2)via bridge site and further transfer the adsorbed N_(2)to the H site,which will dramatically deteriorate the reactivity of N_(2)dissociation.In addition,the following protonation processes of dissociated∗N atoms are all exothermal at 348 K on Ir(100),indicating that the ammonia synthesis can occur spontaneously as the temperature higher than 348 K.These results have provided a reasonable materials design scheme for subsequent ammonia synthesis. 展开更多
关键词 Density functional theory N_(2) dissociation Ir surface Ammonia synthesis Anti-bonding orbitals Reaction barrier
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Asymptotic Behavior of Almost-orbits of Asymptotically Nonexpansive Semigroups in Banach Spaces(Dedicated to Professor You Zhaoyong for his 60th brithday)
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作者 Xu Hong-KunInstitute of Applied Mathematics, East China University of Chemical Technology, Changhai 200237, China 《工程数学学报》 CSCD 1991年第2期19-30,共12页
Let C be a closed bounded convex subset of a uniformaly convex Banach space X with a Frechet differentiable norm, F= {T(t):t ≥0} an asymptotically noncxpansivc semigroup on C, and u:[0,∞)→ C an almost-orbit of F. T... Let C be a closed bounded convex subset of a uniformaly convex Banach space X with a Frechet differentiable norm, F= {T(t):t ≥0} an asymptotically noncxpansivc semigroup on C, and u:[0,∞)→ C an almost-orbit of F. Then we show that {u(t):t ≥ 0} is almost convergent weakly to a common fixed point y of F, that isweak - lim1/tdr - y uniformly in s≥ 0.This implies that {u(t):t≥ 0} converges weakly to y if and onlyif u is weakly asymptotically regular, i.e lim (u(t + s) - u(t) = 0 weakly for all s≥ 0. 展开更多
关键词 Almost-orbit ASYMPTOTICALLY NONEXPANSIVE SEMIGROUP ALMOST convergence fixed point NONEXPANSIVE retraction.
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星载二维转台目标捕获及跟踪指向控制
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作者 王丽娇 陶佳伟 +1 位作者 王淑一 雷拥军 《中国空间科学技术(中英文)》 北大核心 2026年第1期145-156,共12页
针对星载二维转台对空间非合作目标的捕获与跟踪控制问题,充分考虑相机成像特性,设计了从目标初始捕获到视觉跟踪的全流程指向控制策略。首先,目标捕获阶段,考虑相机安装误差及多通道视场中心不重合等因素,通过分析相机图像输出与转台... 针对星载二维转台对空间非合作目标的捕获与跟踪控制问题,充分考虑相机成像特性,设计了从目标初始捕获到视觉跟踪的全流程指向控制策略。首先,目标捕获阶段,考虑相机安装误差及多通道视场中心不重合等因素,通过分析相机图像输出与转台姿态的运动学关系,将相机视轴指向误差映射为转台姿态偏移量,实现了相机视轴与转台末端存在不垂直误差情况下的高精度目标姿态计算,解决了传统方法难以获得解析解的问题。其次,视觉跟踪阶段,针对初始阶段的控制平稳性问题,提出一种基于速度约束能力和像移终端偏差实时调节的像平面轨迹规划策略;针对相机多通道切换的平稳性问题,利用切换点焦平面物理位置的一致性,构建了一种统一坐标尺度的焦平面控制方法,并设计了基于像空间轨迹预估的图像反馈控制策略,通过星体/转台姿态和像平面位置测量预估像平面速度,避免了对像平面速度测量的依赖。进一步优化控制器切换逻辑,引入加权遗忘因子建立切换初期的平稳衔接,兼顾动态速度约束指标及平稳性,提升了系统的鲁棒性和动态性能。最后,验证与应用,通过地面物理试验及在轨应用对上述控制方法进行验证。结果表明,该方法可实现对空间目标的高精度捕获及高平稳跟踪。因此,提出的控制方法有效解决了相机成像约束下的星载二维转台全流程指向控制问题,具有工程实用性。 展开更多
关键词 二维转台 非合作目标 捕获与跟踪 全流程 物理试验 在轨应用
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HVDC输电系统次同步振荡(SSO)分析的GUI实现 被引量:5
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作者 杨帆 王西田 陈陈 《中国电力》 CSCD 北大核心 2005年第1期23-26,共4页
为提高研究效率并普及研究结果,开发了一个用于分析HVDC输电系统次同步振荡(SSO)特性的图形用户界面(GUI)软件。这个GUI软件由人机界面及相关的回调函数组成,其中人机界面是利用MATLAB的GUI工具设计的,而编写回调函数则利用了MATLAB的... 为提高研究效率并普及研究结果,开发了一个用于分析HVDC输电系统次同步振荡(SSO)特性的图形用户界面(GUI)软件。这个GUI软件由人机界面及相关的回调函数组成,其中人机界面是利用MATLAB的GUI工具设计的,而编写回调函数则利用了MATLAB的数值计算和数据可视化功能。实践表明在MATLAB环境下可容易、高效地开发出令人满意的GUI软件。通过GUI软件可实现SSO参数稳定域可视化分析及特征值分析和时域仿真分析,具有直观、方便的优点,适合广大技术人员对HVDC输电系统发生SSO失稳可能性的检验。 展开更多
关键词 电力系统 HVDC 状同步振荡(sso) 图形用户界面(GUT) 人机界面 回调函数
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用PCR-SSO方法研究云南西部彝族HLA-DQB1基因的多态性 被引量:8
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作者 陈为民 黄洪莲 +4 位作者 刘泽寰 陶洪 潘德京 林蒋海 徐安龙 《Acta Genetica Sinica》 SCIE CAS CSCD 北大核心 2001年第2期107-114,共8页
应用PCR朣SO基因分型技术,对我国云南西部地区3代内无血缘关系的76个彝族健康个体进行了HLA-DQB1位点的基因分型。结果显示,在DQB1的38个等位基因中,观察到13个等位基因。云南西部彝族表现为DQB1*0301(36.18%~36.84%)最常见。其... 应用PCR朣SO基因分型技术,对我国云南西部地区3代内无血缘关系的76个彝族健康个体进行了HLA-DQB1位点的基因分型。结果显示,在DQB1的38个等位基因中,观察到13个等位基因。云南西部彝族表现为DQB1*0301(36.18%~36.84%)最常见。其他频率大于5%的等位基因还有DQB1*0502(10.53%~11.18%)、DQB1*0401(9.21%)、DQB1*0302(8.55%~9.21%)、DQB1*0601(7.89%)、DQB1*05031(6.58%)、DQB1*03032(5.92%~6.58%)。和其他13个华人群体DQB1等位基因的频率比较分析表明,总体上,云南西部彝族和其他各华人群体间都存在很大的差异。显示其HLA等位基因频率分布的民族独特性。 展开更多
关键词 彝族 PCR-sso LA-DQB1 云南 HLA基因 多态性
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低轨卫星通信与地面移动通信系统的协同组网探讨
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作者 刘兴 顾柄楠 +2 位作者 吴明亮 孙伟龙 李士鑫 《通信电源技术》 2026年第1期180-182,共3页
针对低轨卫星通信与地面移动通信系统的协同组网展开研究。通过设计星地协同架构,提出包含协议转换、设备配置和关键技术的完整组网方案,重点突破数据传输速率提高与抗干扰等核心技术。通过实验验证了该方案在覆盖范围扩展、服务质量保... 针对低轨卫星通信与地面移动通信系统的协同组网展开研究。通过设计星地协同架构,提出包含协议转换、设备配置和关键技术的完整组网方案,重点突破数据传输速率提高与抗干扰等核心技术。通过实验验证了该方案在覆盖范围扩展、服务质量保障和经济效益优化3个维度具有的显著优势,为构建全域通信网络提供了技术支撑。 展开更多
关键词 低轨卫星通信 地面移动通信系统 协同组网
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面向风电场SSO抑制的TCSC参数电磁暂态智能优化方法 被引量:15
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作者 黄杰 陈武晖 +1 位作者 董德勇 谭伦农 《电网技术》 EI CSCD 北大核心 2015年第9期2411-2417,共7页
抑制风电场次同步振荡(sub-synchronous oscillations,SSO)的晶闸管可控串联补偿装置(thyristor controlled series compensation,TCSC)参数优化问题是强非线性参数优化问题,很难用解析方法求解。文中将单纯形算法(Simplex)与电磁暂态... 抑制风电场次同步振荡(sub-synchronous oscillations,SSO)的晶闸管可控串联补偿装置(thyristor controlled series compensation,TCSC)参数优化问题是强非线性参数优化问题,很难用解析方法求解。文中将单纯形算法(Simplex)与电磁暂态仿真程序结合的非线性参数优化方法引入到抑制SSO的TCSC参数的优化。该算法使用电磁暂态程序的仿真结果计算优化目标函数值,Simplex算法应用电磁暂态程序计算的优化目标函数结果智能地指导TCSC参数寻优方向,快速可靠地寻到最优参数,缩短仿真耗时。最后,针对风电不确定性,初步分析了风速变化对参数优化结果的影响,根据所采用的单机等值系统仿真结果分析,风速变化对TCSC参数优化结果的影响并不显著。 展开更多
关键词 电磁暂态仿真 单纯形算法 次同步振荡 可控串联补偿
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应用SSP-PCR/SSO方法进行中国辽宁汉族人HLA-DRB1基因的遗传多态性研究 被引量:8
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作者 刘利民 梁健 +1 位作者 宋芳吉 贾静涛 《遗传》 CAS CSCD 北大核心 1999年第3期20-24,共5页
对159名中国辽宁汉族个体的基因组DNA进行分析,共检出42种等位基因,其中以DRB109012(12.8%)、0701(10.7%)、1501(10.4%)最为常见,其次为DRB11201(79%)、1... 对159名中国辽宁汉族个体的基因组DNA进行分析,共检出42种等位基因,其中以DRB109012(12.8%)、0701(10.7%)、1501(10.4%)最为常见,其次为DRB11201(79%)、1202(75%)、1101(66%)、0301(5.0%)。并发现辽宁汉族人DRB1等位基因频率与白种人间存在明显差异,揭示不同人种有其自己的主要等位基因。 展开更多
关键词 HLA-DRB1 基因分型 SSP-PCR 遗传多态性
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基于页面集成的统一身份认证SSO系统的实现 被引量:4
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作者 叶晓彤 王飞 《四川理工学院学报(自然科学版)》 CAS 2009年第5期51-54,共4页
文章针对目前的统一身份认证和单点登录解决方案存在技术环节多、成本高、运行风险大等问题,提出一种简易实现方式,采用了WEB页面集成的方式,通过建立用户信息映射表、模拟form表单和URL参数传递等关键技术实现,具有技术简捷、成本低、... 文章针对目前的统一身份认证和单点登录解决方案存在技术环节多、成本高、运行风险大等问题,提出一种简易实现方式,采用了WEB页面集成的方式,通过建立用户信息映射表、模拟form表单和URL参数传递等关键技术实现,具有技术简捷、成本低、运行风险小的特点,适合于对统一身份认证和SSO要求相对不高的单位使用。提高了原方案的整体安全性,并更具实用性。 展开更多
关键词 统一身份认证 sso系统 FORM表单 URL参数
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基于分解策略的SSO发射轨道遗传全局优化设计 被引量:7
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作者 罗亚中 唐国金 梁彦刚 《航空学报》 EI CAS CSCD 北大核心 2004年第5期443-446,共4页
提出了基于轨道分解优化和遗传算法(GA)的SSO发射轨道优化设计策略。针对多个轨道段相互耦合问题,基于分解优化策略,将整个发射轨道设计问题分解为两个轨道段设计问题。为了高效可靠地获得全局最优解,对基本遗传算法进行了改进。首先提... 提出了基于轨道分解优化和遗传算法(GA)的SSO发射轨道优化设计策略。针对多个轨道段相互耦合问题,基于分解优化策略,将整个发射轨道设计问题分解为两个轨道段设计问题。为了高效可靠地获得全局最优解,对基本遗传算法进行了改进。首先提出了基于多变异操作等改进措施的改进遗传算法;此外,结合遗传算法的全局搜索特性和Powell算法的局部搜索特性,设计了一种串行混合遗传算法。一个二级SSO运载火箭的计算结果表明,轨道分解优化策略确保了问题的成功求解,改进遗传算法和混合遗传算法均可稳定地获得全局最优解,但是混合算法更有效地提高了GA性能。 展开更多
关键词 运载火箭 sso发射轨道优化 分解优化策略 混合遗传算法 全局优化
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流式磁珠反向SSO法HLA分型结果判读影响因素及解决对策的研究 被引量:5
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作者 高素青 程曦 +4 位作者 方卫华 金士正 王大明 唐斯 邹红岩 《中国输血杂志》 CAS CSCD 2007年第4期295-297,共3页
目的研究流式磁珠反向SSO法HLA-A、B、DRB1分型结果判读中出现的常见问题,并提出相应的解决策略。方法对3 219名随机抽取的深圳市无关造血干细胞供者及组织配型患者的DNA采用流式磁珠反向SSO法进行HLA-A、B、DRB1低分辨基因分型,模棱两... 目的研究流式磁珠反向SSO法HLA-A、B、DRB1分型结果判读中出现的常见问题,并提出相应的解决策略。方法对3 219名随机抽取的深圳市无关造血干细胞供者及组织配型患者的DNA采用流式磁珠反向SSO法进行HLA-A、B、DRB1低分辨基因分型,模棱两可结果用PCR-序列特异性引物(Sequence Specific Primer,SSP)法及PCR-SBT测序方法等方法复核确认。结果3 219份样本中发现有95份(95/3 219)28种类型的模棱两可结果,其中HLA-A位点有3(3/28)种,HLA-B位点有25(25/28)种,91.6%的模棱两可结果其样本的荧光值在阳性控制线上,本研究观察到的模棱两可结果通过基因频率分析、PCR-SSP法及PCR-SBT基因测序等方法得以定型。结论建立流式磁珠反向SSO法HLA-A、B、DRB1基因分型模棱两可结果解决策略,对提高HLA数据分析的速度和分型的准确性有重要的意义。 展开更多
关键词 人类白细胞抗原(HLA) 流式磁珠反向sso 基因分型
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