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Acta Mathematica Scientia 2010年第2期30卷 499-521页

作者： Shuqiang Wang Roman Samulyak tongfei guo Department of Applied Mathematics and Statistics Stony Brook University Stony Brook NY 11794 USA Computational Science Center Brookhaven National Laboratory Upton NY 11973 USA

The embedded boundary method for solving elliptic and parabolic problems in geometrically complex domains using Cartesian meshes by Johansen and Colella （1998, J. Comput. Phys. 147, 60） has been extended for elliptic and parabolic problems with interior boundaries or interfaces of discontinuities of material properties or solutions. Second order accuracy is achieved in space and time for both stationary and moving interface problems. The method is conservative for elliptic and parabolic problems with fixed interfaces. Based on this method, a front tracking algorithm for the Stefan problem has been developed. The accuracy of the method is measured through comparison with exact solution to a two-dimensional Stefan problem. The algorithm has been used for the study of melting and solidification problems.

关键词： embedded boundary method elliptic interface problem front tracking Ste-fan problem

Design and validation of real-time dynamic spectrum management in OFDM-based HNPLC systems

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High Technology Letters 2015年第4期21卷 379-387页

作者：刘雯静 guo Jingbo Yan Yanxin Zhang tongfei State Key Lab of Control and Simulation of Power Systems and Generation Equipment Department of Electrical EngineeringTsinghua University ROHM Semiconductor(Shanghai) Co. Ltd.Design Center

Time-varying frequency selective attenuation and colored noises are unfavorable characteristics of power line communication(PLC) channels of the low voltage *** overcome these disadvantages,a novel real-time dynamic spectrum management(DSM) algorithm in orthogonal frequency division multiplexing(OFDM)-based high-speed narrow-band power line communication(HNPLC) systems is proposed,and the corresponding FPGA circuit is designed and *** of the proposed DSM is validated with a large amount of network experiments under practical PLC *** the noise in each narrow subcarrier is approximately Gaussian,the proposed DSM adopts the BER/SER expression formulized via the AWGN channel to provide a handy and universal strategy for power *** real-time requirement is guaranteed by choosing subcarriers in group and employing the same modulation scheme within each *** measures are suitable for any modulation scheme no matter the system criterion is to maximize data rate or minimize power/*** design and hardware implementation of the proposed DSM are given with some flexible and efficient *** DSM circuit is carried out with Xilinx *** and practical experiments validate that the proposed real-time DSM significantly improves system performance.

关键词： real-time dynamic spectrum management high-speed narrowband power line com-munication (HNPLC) subcarrier grouping rate adaptive multi-carrier

基于fMRI低频振幅比率分析调神法针刺治疗早醒型失眠的中枢机制研究

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针灸临床杂志 2024年第8期40卷 10-16页

作者：宋章筱姜同菲尹雪娇朱丽颖郭静北京中医药大学北京100029 首都医科大学附属北京中医医院针灸中心针灸神经调控北京市重点实验室北京100010

目的:基于静息态功能磁共振成像(rs-fMRI)研究调神法针刺治疗早醒型失眠的潜在中枢机制。方法:将48例早醒型失眠患者随机分为调神法针刺组(24例,脱落1例)和非穴位浅刺组(24例,脱落1例,剔除1例)。调神法针刺组予针刺百会、神庭、四神聪... 详细信息

目的:基于静息态功能磁共振成像(rs-fMRI)研究调神法针刺治疗早醒型失眠的潜在中枢机制。方法:将48例早醒型失眠患者随机分为调神法针刺组(24例,脱落1例)和非穴位浅刺组(24例,脱落1例,剔除1例)。调神法针刺组予针刺百会、神庭、四神聪、本神、神门、内关和三阴交;非穴位浅刺组予非效穴旁开1寸浅刺治疗,非效穴取臂臑、手三里、阳池、外关、风市、伏兔和梁丘;两组均治疗4周,每周3次,比较两组患者针刺前后匹兹堡睡眠质量指数(PSQI)及早醒评分、汉密尔顿抑郁量表(HAMD-17)评分及早醒评分和汉密尔顿焦虑量表(HAMA)评分,治疗前后进行rs-fMRI数据采集。观察两组患者针刺前后低频振幅比率(fALFF)的变化,fALFF值与量表进行相关性分析。结果:治疗后,调神法针刺组PSQI评分、PSQI早醒评分、HAMD评分、HAMD早醒评分和HAMA评分均较治疗前显著降低,差异具有统计学意义(P<0.01),且量表评分均显著低于非穴位浅刺组,差异具有统计学意义(P<0.05)。非穴位浅刺组HAMA评分较治疗前显著降低,差异具有统计学意义(P<0.01)。治疗后调神法针刺组较非穴位浅刺组fALFF值在左侧背外侧额上回(SFGd)升高、左侧小脑4_5区(CER4_5)降低,差异具有统计学意义(均GRF校正,体素水平P<0.01,团块水平P<0.01,双尾),左SFGd的fALFF值与PSQI评分(r=0.386)、PSQI早醒评分(r=0.330)和HAMD评分(r=0.358)呈显著正相关,差异具有统计学意义(P<0.05),左CER4_5的fALFF值与PSQI评分(r=0.374)、HAMD评分(r=0.483)呈显著负相关,差异具有统计学意义(P<0.05)。结论:调神法针刺可能通过调节早醒型失眠患者的局部脑功能强度,从而有效改善睡眠质量和早醒症状,缓解焦虑、抑郁情绪。

关键词：早醒型失眠针刺静息态功能磁共振成像低频振幅比率

调神方针刺改善慢性失眠患者入睡潜伏期及过度觉醒的临床研究

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针灸临床杂志 2024年第9期40卷 10-15页

作者：朱丽颖陈坤姜同菲陈昭伊王桂玲郭静北京中医药大学北京100029 首都医科大学附属北京中医医院针灸中心针灸神经调控北京市重点实验室北京100010

目的:观察调神方针刺对改善慢性失眠患者入睡潜伏期和过度觉醒状态的临床疗效。方法:将100例慢性失眠患者随机分为治疗组和对照组,各50例。治疗组予调神方针刺得气,穴取百会、神庭、四神聪、本神、神门、内关和三阴交;对照组取治疗失眠... 详细信息

目的:观察调神方针刺对改善慢性失眠患者入睡潜伏期和过度觉醒状态的临床疗效。方法:将100例慢性失眠患者随机分为治疗组和对照组,各50例。治疗组予调神方针刺得气,穴取百会、神庭、四神聪、本神、神门、内关和三阴交;对照组取治疗失眠无效的经穴浅刺。每次均留针30 min,3次/周,治疗4周,给予相同的睡眠卫生指导。比较两组患者治疗前后及治疗结束后第8周随访期睡眠日记记录的入睡潜伏期、匹兹堡睡眠质量指数(PSQI)评分及过度觉醒量表(HAS)评分变化,并分析治疗后入睡潜伏期改善情况与过度觉醒水平变化的相关性。结果:治疗4周后,治疗组入睡潜伏期较前减短,差异具有统计学意义(P<0.01),随访期,两组入睡潜伏期均较前减短,差异具有统计学意义(P<0.05);治疗后及随访期,两组PSQI评分及HAS评分均较治疗前降低,差异具有统计学意义(P<0.05)。治疗4周后,治疗组入睡潜伏期低于对照组,差异具有统计学意义(P<0.01),治疗后及随访期PSQI评分及HAS评分均较对照组明显下降,差异具有统计学意义(P<0.05)。入睡潜伏期减少与过度觉醒水平降低呈正相关。结论:调神方针刺能有效减短慢性失眠患者的入睡潜伏期,提高睡眠质量,而降低过度觉醒水平是减少睡眠潜伏期的潜在机制。

关键词：慢性失眠调神方针刺入睡潜伏期过度觉醒临床试验

从腹气街理论探讨针刺治疗单纯性肥胖的临床思路

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针灸临床杂志 2024年第5期40卷 6-9页

作者：尹睿宋章筱朱丽颖姜同菲王桂玲郭静北京中医药大学临床医学院北京100029 首都医科大学北京100069 首都医科大学附属北京中医医院北京100010

单纯性肥胖已成为严重危害人类健康的流行性疾病,临床表现为体脂含量过多而堆积,分布多倾向于腹内型。目前,针灸在减轻肥胖方面取得了可靠的临床效果,而腹气街理论对针灸治疗取穴起着重要的指导作用。本研究根据单纯性肥胖的临床特征,... 详细信息

单纯性肥胖已成为严重危害人类健康的流行性疾病,临床表现为体脂含量过多而堆积,分布多倾向于腹内型。目前,针灸在减轻肥胖方面取得了可靠的临床效果,而腹气街理论对针灸治疗取穴起着重要的指导作用。本研究根据单纯性肥胖的临床特征,结合腹气街的位置和功能,从脏腑和经络两个层面分析腹气街和肥胖病因病机关系,探讨腹气街理论对于针刺治疗单纯性肥胖的指导意义。

关键词：腹气街单纯性肥胖针刺

高速窄带OFDM电力线通信实时动态频谱分配

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中国电机工程学报 2014年第4期34卷 695-701页

作者：张童飞郭静波电力系统及发电设备控制和仿真国家重点实验室(清华大学电机系) 北京市海淀区100084

动态频谱分配应用于实际电力线通信系统面临分配策略、实时算法等诸多挑战,到目前为止还未见有公开报道。定义并设计了一个实际的基于正交频分复用(orthogonal frequency division multiplexing,OFDM)的高速窄带电力线通信系统构架,并... 详细信息

动态频谱分配应用于实际电力线通信系统面临分配策略、实时算法等诸多挑战,到目前为止还未见有公开报道。定义并设计了一个实际的基于正交频分复用(orthogonal frequency division multiplexing,OFDM)的高速窄带电力线通信系统构架,并提出一种适用于该系统的动态频谱分配策略和对应的实时实现算法。该算法在任一种调制方式下将子载波进行分组,并对各个子载波组的功率进行排序,选择可用的子载波组,根据速率最大化准则确定最优的调制方式并分配功率。该算法与Hughes-Hartogs算法相比,具有较低的运算复杂度和较少的信令开销,与传统的等功率分配方式相比,误码性能更好。仿真结果和实验结果证明了该算法的有效性和优越性。

关键词：高速窄带电力线通信正交频分复用速率自适应动态频谱分配

guo PEI Chinas fashion empress on creating Chinese couture

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城市漫步（上海版、英文） 2014年第11期 28-31页

作者： MARIANNA CERINI tongfei ZHANG 不详

Hailed as the Chinese Coco Chanel although more akin to Alexander McQueen and John Galliano,guo Pei is Chinas couturiere extraordinaire-the reason bespoke fashion exists in the *** chat with the designer about her wor... 详细信息

关键词： fashion harsh creating

原子转移自由基法合成4-(4′-甲氧基苯基甲亚胺)苯酚功能化的六臂星型聚苯乙烯

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高分子学报 2007年第6期17卷 577-581页

作者：于喜飞张国石彤非安立佳吉林大学化学学院教育部汽车材料重点实验室长春130023 中国科学院长春应用化学研究所高分子物理与化学国家重点实验室长春130022

A new initiator for atom transfer radical polymerization（ATRP）,（Cl2HCCOO）3-C6H3,（TrDCAP）,has been designed and successfully *** of styrene was carried out by using TrDCAP as hexafunctional initiator and the CuCl/bpy catalyst at 130℃ in 30% THF via core-first *** Arm-6 PS-AAP was synthesized by etherealization of Arm-6 PS and 4-（4′-methoxyphenylazomethine）phenol（AAP）.The initiator and the architectures of the Arm-6 PS were confirmed by （）1H-NMR,FT-IR,UV-Vis and GPC.

关键词：原子转移自由基聚合星型聚合物

氨基酸功能化的果胶/姜黄素胶体粒子的合成与性质

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高等学校化学学报 2016年第2期37卷 381-387页

作者：杨泽川李帆黄庆荣张国石彤非吉林大学材料科学与工程学院长春130012 中国科学院长春应用化学研究所高分子物理与化学国家重点实验室长春130022 Department of Food Science Rutgers University New Jersey 08901 USA

通过酯化反应合成了新型的氨基酸功能化的果胶衍生物,通过红外光谱(FTIR)和元素分析确认了果胶衍生物的化学组成及结构,用动态光散射(DLS)和透射电子显微镜(TEM)表征了果胶衍生物胶体的形貌和尺寸.结果表明,果胶衍生物胶体呈现不规则的... 详细信息

通过酯化反应合成了新型的氨基酸功能化的果胶衍生物,通过红外光谱(FTIR)和元素分析确认了果胶衍生物的化学组成及结构,用动态光散射(DLS)和透射电子显微镜(TEM)表征了果胶衍生物胶体的形貌和尺寸.结果表明,果胶衍生物胶体呈现不规则的球状结构,粒度分布较均一,平均粒径200 nm.用紫外-可见(UV-Vis)光谱测试了果胶衍生物胶体对姜黄素的包裹和控制释放,结果表明,姜黄素能够有效被果胶衍生物胶束包裹.体外细胞毒理实验结果表明,果胶衍生物胶体载体能显著提高姜黄素对Hep G2细胞生长的抑制作用.

关键词： p H响应胶体粒子药物输运肿瘤抑制氨基酸功能化果胶衍生物姜黄素

Identification of floral fragrance components in an F_(1) population derived from Paeonia ostii 'Fengdan' × P. suffruticosa 'Chunguihuawu' Cross

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Ornamental Plant Research 2022年第1期2卷 205-214页

作者： tongfei Niu Chenjie Zhang Can Wang Xian Xue Yabing Zhang Lili guo Xiaogai Hou College of Agriculture/Tree Peony Henan University of Science&TechnologyLuoyangHenan 471023China

Tree peony(Paeonia suffruticosa Andr.)is a unique aromatic plant famous for its huge flowers,bright colors and strong fragrance,having high ornamental,medicinal,and edible *** on tree peony's flower fragrance has mainly focused on the comparative analysis among its varieties,leaving the inheritance of aroma compounds in this plant an overlooked area of ***,the volatile components of flowers at three different flowering stages of the light fragrance-type cultivar ***'Fengdan'and the strong fragrance-type cultivar ***'Chunguihuawu',as well as the half-opening stage flowers of 109 F_(1) progeny,were collected and characterized in-depth by dynamic headspace sampling technique combined with gas chromatography-mass spectrometry(GC-MS).Diverse profiles of volatiles that included alcohols,esters,aldehydes,terpenes,benzenes,and hydrocarbons were identified from the evaluated *** results revealed that the volatile components and content of parents were significantly different,and that hybridization generated more complex volatile *** volatile compounds in the hybrids,especially the main aromatic components,existed in at least one of the parents,being characterized by intermediate or transgressive inheritance for the floral trait;this demonstrated that volatile compounds can be inherited from parents to ***,seven de novo aroma compounds—those present in progeny yet absent in their parents—were found in *** study preliminarily clarified the segregation performance of aroma traits in tree peony hybrids,which might provide a theoretical basis for selecting breeding parents and the breeding of new varieties for aroma traits.

关键词： volatile aromatic aldehydes