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Constructing Hopf Insulator from Geometric Perspective of Hopf Invariant
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作者 常治文 郝维昌 +1 位作者 Miguel Bustamante 刘鑫 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第3期121-126,共6页
We propose a method to construct Hopf insulators based on the study of topological defects from the geometric perspective of Hopf invariant I.Firstly,we prove two types of topological defects naturally inhering in the... We propose a method to construct Hopf insulators based on the study of topological defects from the geometric perspective of Hopf invariant I.Firstly,we prove two types of topological defects naturally inhering in the inner differential structure of the Hopf mapping.One type is the four-dimensional point defects. 展开更多
关键词 HOPF TOPOLOGICAL invariant
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Factor Structure and Longitudinal Invariance of the CES-D across Diverse Residential Backgrounds in Chinese Adolescents
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作者 Yanjing Cao Chenchen Xu +2 位作者 Qi Li Shan Lu Jing Xiao 《International Journal of Mental Health Promotion》 2024年第4期261-269,共9页
Background:Valid and reliable measures of depressive symptoms are crucial for understanding risk factors,outcomes,and interventions across rural and urban settings.Despite this need,the longitudinal invariance of thes... Background:Valid and reliable measures of depressive symptoms are crucial for understanding risk factors,outcomes,and interventions across rural and urban settings.Despite this need,the longitudinal invariance of these measures over time remains understudied.This research explores the structural components of the Center for Epidemiological Studies Depression Scale(CES-D)and examines its consistency across various living environments and temporal stability in a cohort of Chinese teenagers.Method:In the initial phase,1,042 adolescents furnished demographic details and undertook the CES-D assessment.After a three-month interval,967 of these participants repeated the CES-D evaluation.The study employed Confirmatory factor analysis(CFA)to scrutinize the scale’s structural integrity.We investigated factorial invariance by conducting a twopronged CFA:one comparing urban vs.rural backgrounds,and another contrasting the results from the initial assessment with those from the follow-up.Results:The CES-D demonstrated adequate reliability in both rural and urban high school student samples.The preliminary four-factor model applied to the CES-D demonstrated a good fit with the collected data.Invariance tests,including multigroup analyses comparing rural and urban samples and longitudinal assessments,confirmed the scale’s invariance.Conclusions:The results suggest that the CES-D serves as a reliable instrument for evaluating depressive symptoms among Chinese adolescents.Its applicability is consistent across different living environments and remains stable over time. 展开更多
关键词 DEPRESSION factor structure measurement invariance Chinese adolescent longitudinal invariance
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Accounting for Quadratic and Cubic Invariants in Continuum Mechanics–An Overview
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作者 Artur V.Dmitrenko Vladislav M.Ovsyannikov 《Fluid Dynamics & Materials Processing》 EI 2024年第9期1925-1939,共15页
The differential equations of continuum mechanics are the basis of an uncountable variety of phenomena and technological processes in fluid-dynamics and related fields.These equations contain derivatives of the first ... The differential equations of continuum mechanics are the basis of an uncountable variety of phenomena and technological processes in fluid-dynamics and related fields.These equations contain derivatives of the first order with respect to time.The derivation of the equations of continuum mechanics uses the limit transitions of the tendency of the volume increment and the time increment to zero.Derivatives are used to derive the wave equation.The differential wave equation is second order in time.Therefore,increments of volume and increments of time in continuum mechanics should be considered as small but finite quantities for problems of wave formation.This is important for calculating the generation of sound waves and water hammer waves.Therefore,the Euler continuity equation with finite time increments is of interest.The finiteness of the time increment makes it possible to take into account the quadratic and cubic invariants of the strain rate tensor.This is a new branch in hydrodynamics.Quadratic and cubic invariants will be used in differential wave equations of the second and third order in time. 展开更多
关键词 Quadratic invariant cubic invariant continuity equation generation of periodic waves N.E.Zhukovsky’s hydraulic shock TURBULENCE
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Solving Invariant Problem of Cauchy Means Based on Wronskian Determinant
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作者 Yingjun Ni Fen Wang 《Advances in Pure Mathematics》 2024年第7期515-522,共8页
This paper studied the invariance of the Cauchy mean with respect to the arithmetic mean when the denominator functions satisfy certain conditions. The partial derivatives of Cauchy’s mean on the diagonal are obtaine... This paper studied the invariance of the Cauchy mean with respect to the arithmetic mean when the denominator functions satisfy certain conditions. The partial derivatives of Cauchy’s mean on the diagonal are obtained by using the method of Wronskian determinant in the process of solving. Then the invariant equation is solved by using the obtained partial derivatives. Finally, the solutions of invariant equations when the denominator functions satisfy the same simple harmonic oscillator equation or the denominator functions are power functions that have been obtained. 展开更多
关键词 Cauchy Mean Wronskian Determinant Arithmetic Mean invariant Equation
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S-烯虫乙酯对德国小蠊的现场控制效果研究
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作者 朱敏慧 刘丽军 +2 位作者 周毅彬 徐智寅 刘洪霞 《寄生虫与医学昆虫学报》 CAS 2024年第2期111-114,128,共5页
目的探索S-烯虫乙酯对德国小蠊的现场控制效果。方法选择2个农贸市场作为研究对象,实验组使用S-烯虫乙酯药片贴进行德国小蠊控制,对照组使用商家自行购药控制德国小蠊密度。通过比较2个市场的德国小蠊密度变化和发育繁殖情况,评估S-烯... 目的探索S-烯虫乙酯对德国小蠊的现场控制效果。方法选择2个农贸市场作为研究对象,实验组使用S-烯虫乙酯药片贴进行德国小蠊控制,对照组使用商家自行购药控制德国小蠊密度。通过比较2个市场的德国小蠊密度变化和发育繁殖情况,评估S-烯虫乙酯对德国小蠊的控制效果。结果实验组在投药30 d后德国小蠊总密度下降明显,密度下降率达到67.11%,若虫密度下降率为79.79%。对照组前60 d总密度变化不大,第90天开始密度上升。统计分析结果表明,实验组与对照组在第90和120天的德国小蠊密度存在显著差异。施药现场带回的德国小蠊若虫中,外形畸形组死亡较早。施药现场带回的10个卵鞘中有3个未孵化,7个卵鞘产生的122只若虫成功羽化40只成虫,其中3个成虫翅膀出现畸形。结论S-烯虫乙酯通过致畸和不育作用,能够减小德国小蠊种群密度,降低其繁殖能力。 展开更多
关键词 s-烯虫乙酯 德国小蠊 致畸
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ω-转氨酶的筛选和异源表达用于制备S-甲氧基异丙胺
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作者 张涛 周海胜 +1 位作者 徐佳琪 杨立荣 《生物学杂志》 CAS CSCD 北大核心 2024年第2期8-15,56,共9页
根据转氨酶家族进化分类和底物特异性,构建一个包含36个ω-转氨酶的酶库;将酶库中的基因克隆进大肠杆菌E.coli BL21 (DE3)中进行异源重组表达,考察酶蛋白表达水平并测定相应的酶活以及对映体选择性。通过筛选,获得最佳的ω-转氨酶为来... 根据转氨酶家族进化分类和底物特异性,构建一个包含36个ω-转氨酶的酶库;将酶库中的基因克隆进大肠杆菌E.coli BL21 (DE3)中进行异源重组表达,考察酶蛋白表达水平并测定相应的酶活以及对映体选择性。通过筛选,获得最佳的ω-转氨酶为来源于巨大芽孢杆菌Bacillus megaterium的ω-转氨酶BmeTA,其重组表达粗酶活为2.0 U/mL,纯酶比活为9.5 U/mg蛋白;酶学性质表征发现其最适温度为35℃,最适pH为8.0。在此基础上进一步优化其催化反应工艺条件,在20 g/L加酶量、0.5 mmol/L辅酶添加量以及1.4的氨基供体/氨基受体比例条件下,反应18 h获得450 mmol/L的S-甲氧基异丙胺,原料转化率达到90%,为实现生物催化制备S-甲氧基异丙胺的工业化奠定基础。 展开更多
关键词 s-甲氧基异丙胺 ω-转氨酶 异源表达 氨基转移 生物催化
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环境因素对BT80S-5Cr抗CO_(2)/H_(2)S腐蚀套管均匀腐蚀速率的影响
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作者 石晓霞 雷鸣 +2 位作者 詹飞 强强 张程远 《钢管》 CAS 2024年第5期15-19,共5页
通过模拟国内某油田腐蚀工况,采用高温高压釜模拟腐蚀试验,利用失重法研究试验周期、温度、CO_(2)及H2S分压环境因素对BT80S-5Cr油套管均匀腐蚀速率的影响。研究表明,随着试验周期的延长,试验钢均匀腐蚀速率逐渐降低,且降幅趋于平缓,试... 通过模拟国内某油田腐蚀工况,采用高温高压釜模拟腐蚀试验,利用失重法研究试验周期、温度、CO_(2)及H2S分压环境因素对BT80S-5Cr油套管均匀腐蚀速率的影响。研究表明,随着试验周期的延长,试验钢均匀腐蚀速率逐渐降低,且降幅趋于平缓,试验周期360 h是BT80S-5Cr在该油气田模拟工况下衡量耐蚀性能的最佳试验周期;随着试验温度的提高,试验钢均匀腐蚀速率逐渐增加,试验温度100℃的试验钢的均匀腐蚀速率是试验温度40℃时的均匀腐蚀速率的1.67倍;随着CO_(2)分压的提高,试验钢均匀腐蚀速率逐渐增加,CO_(2)分压1.0 MPa的试验钢均匀腐蚀速率是不含CO_(2)时的均匀腐蚀速率的10倍;随着H2S分压的提高,试验钢均匀腐蚀速率逐渐降低,微量H_(2)S气体的引入对试验钢电化学腐蚀行为有一定的抑制作用。 展开更多
关键词 套管 BT80s-5Cr 腐蚀速率 CO_(2)/H_(2)S
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有限群的s-半置换子群
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作者 徐向阳 李样明 刘小伟 《应用数学进展》 2024年第7期3220-3226,共7页
设G为有限群, H为G的子群。 若对G的任意满足(|P |, |H|) = 1的Sylow 子群P , 都有GpH = HGp成立,则称H为G的s-半置换子群。 本文,我们主要探究具有若干s-半置换子群的有限群的结构。 我们的结论推广了前人的若干结果。
关键词 s-半置换子群 Sylow p-子群 p- 超可解群 最小生成元数
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帕金森病患者免疫球蛋白、Th9亚群水平变化及其与IGF-1、S-100B蛋白的相关性
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作者 曹利红 张哲 傅天 《中国免疫学杂志》 CAS CSCD 北大核心 2024年第6期1248-1252,共5页
目的:研究帕金森病(PD)患者免疫球蛋白(IgG、IgA和IgM)、辅助性T细胞亚群Th9水平变化及其与胰岛素生长因子-1(IGF-1)、S-100B蛋白的相关性。方法:选取2020年12月至2022年12月期间在河北省中医院确诊的108例PD患者,将其作为研究组,并根... 目的:研究帕金森病(PD)患者免疫球蛋白(IgG、IgA和IgM)、辅助性T细胞亚群Th9水平变化及其与胰岛素生长因子-1(IGF-1)、S-100B蛋白的相关性。方法:选取2020年12月至2022年12月期间在河北省中医院确诊的108例PD患者,将其作为研究组,并根据患者病变程度分为轻度组(35例)、中度组(44例)和重度组(29例);另选108例健康成人作为对照组。对比研究组和对照组免疫球蛋白和Th9亚群水平,以及轻度组、中度组及重度组免疫球蛋白、Th9亚群、IGF-1和S-100B蛋白水平,采用Pearson相关性分析免疫球蛋白、Th9亚群和IGF-1、S-100B蛋白的相关性。采用Spearman相关性分析PD患者疾病程度和所有差异指标间的相关性。结果:研究组IgM水平较对照组低,且重度组低于中度组,中度组低于轻度组(P<0.05);研究组IgG、IgA、IL-9和Th9亚群水平较对照组高,且重度组高于中度组,中度组高于轻度组(P<0.05)。重度组IGF-1水平低于中度组,中度组低于轻度组;重度组S-100B蛋白水平高于中度组,中度组高于轻度组(P<0.05)。Pearson相关性分析结果显示,PD患者IgM水平与IGF-1水平呈正相关,与S-100B蛋白水平呈负相关;IgG、IgA、IL-9和Th9亚群水平均与IGF-1水平呈负相关,与S-100B蛋白水平呈正相关(P<0.05)。Spearman相关性分析结果显示,PD患者疾病程度与IgM、IGF-1水平呈负相关,与S-100B蛋白、IgG、IgA、IL-9和Th9亚群水平呈正相关(P<0.05)。结论:PD患者IgM水平降低,IgG、IgA、Th9亚群水平升高,且其水平变化与IGF-1、S-100B明显相关,可以用于评估病情的严重程度。 展开更多
关键词 帕金森病 免疫球蛋白 辅助性T细胞亚群 胰岛素生长因子-1 s-100B蛋白
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S-诱抗素对杂交稻产量及品质的影响
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作者 魏中伟 马国辉 金文雨 《湖南农业科学》 2024年第9期29-33,共5页
为探寻提高杂交稻产量和品质的栽培调控措施,对甬优4949、玮两优8612和乔两优17开展早、晚稻栽培试验,研究S-诱抗素对其产量及品质的影响。结果表明:S-诱抗素提高了各品种齐穗期SPAD值、光合参数及齐穗、成熟期干物质生产能力。各品种S... 为探寻提高杂交稻产量和品质的栽培调控措施,对甬优4949、玮两优8612和乔两优17开展早、晚稻栽培试验,研究S-诱抗素对其产量及品质的影响。结果表明:S-诱抗素提高了各品种齐穗期SPAD值、光合参数及齐穗、成熟期干物质生产能力。各品种S-诱抗素处理的有效穗数、每穗粒数、结实率及千粒重等产量构成因子均有提高,增产7.8%~11.1%,乔两优17的增产效果更显著。S-诱抗素提高了各品种加工品质中的糙米率、整精米率及蒸煮品质中的碱消值、胶稠度,同时降低了外观品质中的垩白度、垩白粒率及蒸煮品质中的直链淀粉含量。早稻季各品种S-诱抗素处理的整精米率、垩白度、垩白粒率及碱消值与对照相比达到显著差异,S-诱抗素对早稻品质的改善效果优于晚稻。综合结果表明,施用S-诱抗素能够有效提高杂交稻的产量和品质。 展开更多
关键词 s-诱抗素 杂交稻 产量 品质 调控
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S-烯丙基巯基半胱氨酸促进CD8+T细胞杀伤功能的机制研究
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作者 翟健 李军 《中国耳鼻咽喉头颈外科》 CSCD 2024年第2期74-78,共5页
目的探究S-烯丙基巯基半胱氨酸(S-allylmercaptocysteine,SAMC)对CD8^(+)T细胞杀伤鼻咽癌细胞功能的影响及机制。方法将人鼻咽癌细胞HK-1和C666-1与SAMC共培养,分为0、25、50、100μmol/L SAMC组,Western blot检测肿瘤细胞程序性死亡配... 目的探究S-烯丙基巯基半胱氨酸(S-allylmercaptocysteine,SAMC)对CD8^(+)T细胞杀伤鼻咽癌细胞功能的影响及机制。方法将人鼻咽癌细胞HK-1和C666-1与SAMC共培养,分为0、25、50、100μmol/L SAMC组,Western blot检测肿瘤细胞程序性死亡配体-1(programmed cell death-ligand 1,PD-L1)表达。CD8^(+)T细胞分别与HK-1和C666-1细胞以10∶1的比例共培养并加入0、25、50、100μmol/L SAMC,检测CD8^(+)T对HK-1和C666-1的杀伤能力,酶联免疫法(ELISA)检测干扰素(INF-γ)和肿瘤坏死因子-α(TNF-α)浓度,构建鼻咽细胞HK-1的小鼠皮下移植瘤模型,分为对照组、CD8^(+)T细胞组、SAMC组、SAMC+CD8^(+)T细胞组,各组小鼠治疗期间测量瘤体积,治疗结束后取小鼠肿瘤组织,Western blot检测肿瘤组织中PD-L1表达,ELISA检测小鼠血清INF-γ和TNF-α浓度。结果相比于0μmol/L SAMC组,25、50、100μmol/L SAMC组HK-1和C666-1细胞PD-L1表达均显著下调(P<0.05),相比于0μmol/L SAMC+CD8^(+)T细胞组,25、50、100μmol/L SAMC+CD8^(+)T细胞组HK-1和C666-1细胞培养上清中INF-γ和TNF-α浓度均能显著增加,HK-1和C666-1细胞裂解率显著增加(P<0.01)。相比于对照组,CD8^(+)T细胞组和SAMC+CD8^(+)T细胞组小鼠瘤体积和瘤重显著下降(P<0.05),小鼠血清INF-γ和TNF-α浓度显著增加,相比于CD8^(+)T细胞组,SAMC+CD8^(+)T细胞组小鼠瘤体积和瘤重显著下降(P<0.05),小鼠血清INF-γ和TNF-α浓度显著增加(P<0.05),肿瘤组织PD-L1表达显著下调(P<0.01)。结论SAMC可通过抑制人鼻咽癌细胞PD-L1表达而促进CD8^(+)T细胞的杀伤功能。 展开更多
关键词 鼻咽癌 酶联免疫吸附测定 s-烯丙基巯基半胱氨酸 细胞程序性死亡配体-1
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BDS-2/BDS-3卫星观测数据联合处理关键技术研究
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作者 胡超 《测绘学报》 EI CSCD 北大核心 2024年第2期392-392,共1页
高质量卫星观测数据及高精度轨道钟差等产品作为全球导航与位置服务的核心,对整个系统的服务能力起到了至关重要作用。论文针对BDS-2/BDS-3卫星观测数据联合处理中空间构型、快速与高精度处理、轨道钟差精化及观测数据偏差等关键技术进... 高质量卫星观测数据及高精度轨道钟差等产品作为全球导航与位置服务的核心,对整个系统的服务能力起到了至关重要作用。论文针对BDS-2/BDS-3卫星观测数据联合处理中空间构型、快速与高精度处理、轨道钟差精化及观测数据偏差等关键技术进行了深入探讨与系统研究。 展开更多
关键词 卫星观测数据 导航与位置服务 钟差 高精度处理 空间构型 数据偏差 BD s-2
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高速拉拔ER70S-6焊丝钢生产工艺优化
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作者 赵晓敏 罗海炯 +2 位作者 王刚 李学东 白彬亨 《包钢科技》 2024年第1期65-69,共5页
通过总结分析ER70S-6焊丝钢存在的质量问题,提出了有针对性的优化改进措施,重点对ER70S-6焊丝钢的化学成分范围、气体氮含量、尺寸精度、显微组织等关键指标严格控制,攻关后C、Si、Mn、N含量内控达标率提高,尺寸偏差C级精度得到改善,而... 通过总结分析ER70S-6焊丝钢存在的质量问题,提出了有针对性的优化改进措施,重点对ER70S-6焊丝钢的化学成分范围、气体氮含量、尺寸精度、显微组织等关键指标严格控制,攻关后C、Si、Mn、N含量内控达标率提高,尺寸偏差C级精度得到改善,而且消除了混晶异常组织。用户拉拔使用结果表明,优化后的焊丝钢质量得到进一步的提高,可满足用户拉拔速度28 m/s以上高速拉拔的要求。 展开更多
关键词 ER70s-6焊丝钢 氮含量 尺寸精度 高速拉拔
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血清S-100B蛋白、可溶性凝集素样氧化低密度脂蛋白受体-1、胶质纤维酸性蛋白检测在新生儿缺血缺氧性脑病病情严重程度中的诊断价值
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作者 耿淑霞 《陕西医学杂志》 CAS 2024年第1期118-121,共4页
目的:探讨血清S-100B蛋白、可溶性凝集素样氧化低密度脂蛋白受体-1(sLOX-1)、胶质纤维酸性蛋白(GFAP)与新生儿缺血缺氧性脑病(HIE)病情严重程度的关系。方法:选择80例HIE患儿作为观察组,另选择90例健康新生儿作为对照组,收集所有患儿一... 目的:探讨血清S-100B蛋白、可溶性凝集素样氧化低密度脂蛋白受体-1(sLOX-1)、胶质纤维酸性蛋白(GFAP)与新生儿缺血缺氧性脑病(HIE)病情严重程度的关系。方法:选择80例HIE患儿作为观察组,另选择90例健康新生儿作为对照组,收集所有患儿一般资料,并检测两组患儿血清S-100B蛋白、sLOX-1、GFAP水平,分析HIE患儿血清S-100B蛋白、sLOX-1、GFAP与病情严重程度的相关性及预后不良的影响因素。结果:对照组血清S-100B蛋白、sLOX-1、GFAP水平低于观察组(均P<0.05)。重度组血清S-100B蛋白、sLOX-1、GFAP水平高于中度组、轻度组和对照组(均P<0.05)。Pearson相关分析显示,疾病严重程度与HIE患儿血清S-100B蛋白、sLOX-1、GFAP水平呈正相关(均P<0.001)。随访预后良好患儿59例,预后不良21例,经多因素Logistic回归分析显示,产程异常、病情重度、S-100B蛋白、sLOX-1、GFAP为影响HIE患儿预后的危险因素(均P<0.05)。结论:HIE患儿病情严重程度和预后与血清S-100B蛋白、sLOX-1、GFAP水平有关,监测其水平变化有利于临床早期完善干预方案改善预后。 展开更多
关键词 s-100B蛋白 可溶性凝集素样氧化低密度脂蛋白受体-1 胶质纤维酸性蛋白 新生儿缺血缺氧性脑病 相关性 预后
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On entanglement invariant for a double Jaynes-Cummings model 被引量:2
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作者 满忠晓 夏云杰 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第12期4375-4377,共3页
In a recent paper [Phys. Rev. A 76 042313 (2007)], Sainz and Bjork introduced an entanglement invariant ε under evolution for a system of four qubits interacting through two isolated Jaynes-Cummings Hamiltonians. T... In a recent paper [Phys. Rev. A 76 042313 (2007)], Sainz and Bjork introduced an entanglement invariant ε under evolution for a system of four qubits interacting through two isolated Jaynes-Cummings Hamiltonians. This paper proves that this entanglement invariant ε is closely connected with the linear entropy between two independent subsystems. 展开更多
关键词 entanglement dynamics entanglement invariant
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Optimized Evaluation of Mobile Base Station by Modern Topological Invariants
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作者 Khalid Hamid Muhammad Waseem Iqbal +3 位作者 Muhammad Usman Ashraf Ahmed Mohammed Alghamdi Adel A.Bahaddad Khalid Ali Almarhabi 《Computers, Materials & Continua》 SCIE EI 2023年第1期363-378,共16页
Due to a tremendous increase in mobile traffic,mobile operators have started to restructure their networks to offload their traffic.Newresearch directions will lead to fundamental changes in the design of future Fifth... Due to a tremendous increase in mobile traffic,mobile operators have started to restructure their networks to offload their traffic.Newresearch directions will lead to fundamental changes in the design of future Fifthgeneration(5G)cellular networks.For the formal reason,the study solves the physical network of the mobile base station for the prediction of the best characteristics to develop an enhanced network with the help of graph theory.Any number that can be uniquely calculated by a graph is known as a graph invariant.During the last two decades,innumerable numerical graph invariants have been portrayed and used for correlation analysis.In any case,no efficient assessment has been embraced to choose,how much these invariants are connected with a network graph.This paper will talk about two unique variations of the hexagonal graph with great capability of forecasting in the field of optimized mobile base station topology in setting with physical networks.Since K-banhatti sombor invariants(KBSO)and Contrharmonic-quadratic invariants(CQIs)are newly introduced and have various expectation characteristics for various variations of hexagonal graphs or networks.As the hexagonal networks are used in mobile base stations in layered,forms called honeycomb.The review settled the topology of a hexagon of two distinct sorts with two invariants KBSO and CQIs and their reduced forms.The deduced outcomes can be utilized for the modeling of mobile cellular networks,multiprocessors interconnections,microchips,chemical compound synthesis and memory interconnection networks.The results find sharp upper bounds and lower bounds of the honeycomb network to utilize the Mobile base station network(MBSN)for the high load of traffic and minimal traffic also. 展开更多
关键词 Hexagonal networks k-banhatti sombor invariants MAPLE network graph artificial intelligence contraharmonic-quadratic invariants HONEYCOMB
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满足条件(P)的循环序S-系对序幺半群的同调分类
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作者 马娉婷 乔虎生 王欣欣 《兰州大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期134-137,共4页
研究同余λ(x ^(p),x^( q))的一些重要性质,单循环序S-系S/λ(x,x^(2))满足条件(P)和强平坦性的等价刻画以及满足条件(P)的循环序S-系对序幺半群的同调分类.
关键词 循环序s- 条件(P) 单循环序s-
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On the Construction and Classification of the Common Invariant Solutions for Some P(1,4) -Invariant Partial Differential Equations
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作者 Vasyl M. Fedorchuk Volodymyr I. Fedorchuk 《Applied Mathematics》 2023年第11期728-747,共20页
We consider the following (1 + 3)-dimensional P(1,4)-invariant partial differential equations (PDEs): the Eikonal equation, the Euler-Lagrange-Born-Infeld equation, the homogeneous Monge-Ampère equation, the inho... We consider the following (1 + 3)-dimensional P(1,4)-invariant partial differential equations (PDEs): the Eikonal equation, the Euler-Lagrange-Born-Infeld equation, the homogeneous Monge-Ampère equation, the inhomogeneous Monge-Ampère equation. The purpose of this paper is to construct and classify the common invariant solutions for those equations. For this aim, we have used the results concerning construction and classification of invariant solutions for the (1 + 3)-dimensional P(1,4)-invariant Eikonal equation, since this equation is the simplest among the equations under investigation. The direct checked allowed us to conclude that the majority of invariant solutions of the (1 + 3)-dimensional Eikonal equation, obtained on the base of low-dimensional (dimL ≤ 3) nonconjugate subalgebras of the Lie algebra of the Poincaré group P(1,4), satisfy all the equations under investigation. In this paper, we present obtained common invariant solutions of the equations under study as well as the classification of those invariant solutions. 展开更多
关键词 Symmetry Reduction Classification of invariant Solutions Common invariant Solutions The Eikonal Equations The Euler-Lagrange-Born-Infeld Equations The Monge-Ampère Equations Classification of Lie Algebras Nonconjugate Subalgebras Poincaré Group P(1 4)
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Invariant manifold growth formula in cylindrical coordinates and its application for magnetically confined fusion
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作者 魏文崟 梁云峰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第9期51-67,共17页
For three-dimensional vector fields,the governing formula of invariant manifolds grown from a hyperbolic cycle is given in cylindrical coordinates.The initial growth directions depend on the Jacobians of Poincaré... For three-dimensional vector fields,the governing formula of invariant manifolds grown from a hyperbolic cycle is given in cylindrical coordinates.The initial growth directions depend on the Jacobians of Poincarémap on that cycle,for which an evolution formula is deduced to reveal the relationship among Jacobians of different Poincarésections.The evolution formula also applies to cycles in arbitrary finite n-dimensional autonomous continuous-time dynamical systems.Non-Möbiusian/Möbiusian saddle cycles and a dummy X-cycle are constructed analytically as demonstration.A real-world numeric example of analyzing a magnetic field timeslice on EAST is presented. 展开更多
关键词 magnetic topology TOKAMAK invariant manifold
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A road map to higher genus Gromov-Witten invariants of Calabi-Yau quintics
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作者 CHANG Huailiang LI Weiping 《中山大学学报(自然科学版)(中英文)》 CAS CSCD 北大核心 2023年第2期1-9,共9页
This is a survey of using NMSP method to study higher genus Gromov-Witten invariants of Calabi-Yau quintics.It emphasizes on how and why the various methods are introduced to solve several important conjectures for hi... This is a survey of using NMSP method to study higher genus Gromov-Witten invariants of Calabi-Yau quintics.It emphasizes on how and why the various methods are introduced to solve several important conjectures for higher genus Gromov-Witten invariants of Calabi-Yau quintics. 展开更多
关键词 Gromov-Witten invariants Calabi-Yau manifolds
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