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Evaluation of intraoperative MRI-assisted stereotactic brain tissue biopsy: a singlecenter experience in China

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Chinese Neurosurgical Journal 2019年第1期5卷 13-20页

作者： Chang-yu Lu zong-sheng xu xun Ye Department of Neurosurgery Peking University International HospitalBeijingChina Department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijingChina

Background:This study aimed to investigate the value of high field-strength intraoperative magnetic resonance imaging(iMRI)-guided stereotactic biopsy in the surgery of intracranial space-occupying ***:A total of 87 patients who underwent stereotactic biopsy of intracranial lesions in the Peking University International Hospital from March 2016 to August 2018 were retrospectively surveyed;among these,50 patients underwent MRI-guided stereotactic biopsy using the Leksell frame(iMRI group)and 37 cases received traditional stereotactic biopsy using the Leksell frame(control group).The accuracy rates and complications of the two groups were ***:A 100%positive diagnosis was observed in all cases(n=50)in the iMRI *** 4 cases,the biopsy site was clearly found to have deviated from the target point,and the biopsy was performed *** control group had 33 cases(86.5%)with positive *** severe complications like neural functional deficit were observed in the iMRI group,while two patients developed bleeding at the puncture site(1 case receiving surgery to remove the hematoma)in the control *** were no deaths in either ***:iMRI-assisted stereotactic biopsy can confirm the target position and adjust the puncture path in real *** to the traditional stereotactic biopsy technique,the iMRI method has a higher positive diagnostic rate,though surgical trauma and complications have no significant difference.

关键词： High field-strength Stereotactic technique Brain biopsy Intraoperative magnetic resonance

A composite material model for investigation of micro-fracture mechanism of brittle rock subjected to uniaxial compression

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Journal of Central South University of Technology 2001年第4期8卷 258-262页

作者： CHEN Feng,SUN zong qi,xu Ji cheng,ZHANG Jing yi (Key Laboratory of Nonferrous Metal Materials Science & Engineering, Central South University, Changsha 410083, China) 1. Key Laboratory of Nonferrous Metal Materials Science & Engineering Central South University 410083 Changsha China

A two phase model of rock was proposed in order to investigate the mechanism of brittle fracture due to uniaxial compression, in which rock was considered to be a composite material consisting of hard grains and colloids. The stress state in colloid region near grains was calculated using Finite Element Method (FEM). The influence of the tensile stresses on the crack initiation and failure process of brittle rock subjected to uniaxial compression was investigated by numerical experiments. The FE results show that tensile stresses are induced easily in the neighboring area of hard grains with the maximum value near grain boundaries. The distribution of tensile stresses depends on the relative position of hard grains. The cracks initiated just near the boundary area of hard grains, which was governed by tensile stress. These results clearly reveal the micro fracture mechanism of brittle rock loaded by uniaxial compression. It can be concluded that the failure mode of brittle rock under uniaxial compression is still tensile fracture from the point view of microstructure. However, since the wide colloid region is still under compressive stress state, further propagation of boundary cracks through this region obviously needs more external load, thus causing the uniaxial compressive strength of rock much higher than its tensile strength obtained via Brazilian (splitting)

关键词： two-phase model micro-fracture rock uniaxial compression

基于地理位置信息和功率控制的ad hoc网络并行MAC协议

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通信学报 2008年第9期29卷 81-90页

作者：雷磊许宗泽南京航空航天大学信息科学与技术学院江苏南京210016

对暴露终端并行传输产生的冲突干扰问题进行了研究,并在此基础上提出了一种基于地理位置信息和功率控制的ad hoc网络并行MAC协议。该协议利用地理位置信息判断节点的暴露终端身份,并在暴露终端发起的并行传输中引入了功率控制机制。在... 详细信息

对暴露终端并行传输产生的冲突干扰问题进行了研究,并在此基础上提出了一种基于地理位置信息和功率控制的ad hoc网络并行MAC协议。该协议利用地理位置信息判断节点的暴露终端身份,并在暴露终端发起的并行传输中引入了功率控制机制。在并行传输发送成功概率较低的情况下,该协议通过随机退避机制限制并行传输发起的次数,避免了失败的并行传输对其他接收节点产生干扰并导致节点产生不必要的能耗。仿真证明,该协议在显著提高ad hoc网络平均吞吐量的同时,还能有效节省节点的平均能耗,从而延长节点的工作时间和网络的生存时间。

关键词： ad hoc网络 MAC协议并行传输暴露终端

Entanglement and thermalization in the extended Bose–Hubbard model after a quantum quench: A correlation analysis

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Chinese Physics B 2023年第2期32卷 168-174页

作者：苏晓强许宗菊赵有权 College of Physics and Information Engineering Shanxi Normal UniversityTaiyuan 030031China Key Laboratory of Spectral Measurement and Analysis of Shanxi Province Shanxi Normal UniversityTaiyuan 030031China

Exploring the role of entanglement in quantum nonequilibrium dynamics is important to understand the mechanism of thermalization in an isolated system. We study the relaxation dynamics in a one-dimensional extended Bose–Hubbard model after a global interaction quench by considering several observables: the local Boson numbers, the nonlocal entanglement entropy, and the momentum distribution functions. We calculate the thermalization fidelity for different quench parameters and different sizes of subsystems, and the results show that the degree of thermalization is affected by the distance from the integrable point and the size of the subsystem. We employ the Pearson coefficient as the measurement of the correlation between the entanglement entropy and thermalization fidelity, and a strong correlation is demonstrated for the quenched system.

关键词： quantum quench quantum entanglement thermalization extended Bose–Hubbard model

IEEE 802.11 DCF差错帧模型的分析与仿真算法改进

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电子与信息学报 2008年第5期30卷 1234-1238页

作者：雷磊许宗泽南京航空航天大学信息科学与技术学院南京210016

该文提出了IEEE802.11DCF差错帧模型的概念,并在详细分析这一模型的基础上,指出了GloMoSim仿真环境中现有的DCF差错帧模型仿真算法存在的问题,然后严格按照DCF差错帧模型中的相关规约改进了该仿真算法。仿真与分析表明,与GloMoSim中现... 详细信息

该文提出了IEEE802.11DCF差错帧模型的概念,并在详细分析这一模型的基础上,指出了GloMoSim仿真环境中现有的DCF差错帧模型仿真算法存在的问题,然后严格按照DCF差错帧模型中的相关规约改进了该仿真算法。仿真与分析表明,与GloMoSim中现有的仿真算法相比,改进后的仿真算法能正确地模拟IEEE802.11DCF协议处理差错帧的相关规约,为仿真实验提供了更加可靠的结果。

关键词： Ad hoc网络 DCF协议差错帧模型 GloMoSim

文化转型时代的思想革新与文风变迁——论元和诗变与元和体

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齐鲁学刊 2007年第3期 61-65页

作者：许总国立华侨大学文学院福建泉州362021

唐代中期的贞元、元和之际,为适应社会政治秩序的重建和庶族文人登上政治舞台的需要,传统儒学得到新的阐释,从而促发思想革新和文风变迁,其最突出的表现是儒家政教文学观的高扬和文学复古运动的蓬勃开展。同时,元和时代又蕴藏着深刻的... 详细信息

唐代中期的贞元、元和之际,为适应社会政治秩序的重建和庶族文人登上政治舞台的需要,传统儒学得到新的阐释,从而促发思想革新和文风变迁,其最突出的表现是儒家政教文学观的高扬和文学复古运动的蓬勃开展。同时,元和时代又蕴藏着深刻的社会矛盾,在文人理想破灭和心理的压抑下,使得元和文学在“明道”、“讽谕”之外,进而衍生两大流向:一是偏重奇险崛奥,二是偏重感伤闲适。作为当时文坛最重要现象的“元和诗变”,实际上正是那一特定的文化转型时代政治的、思想的、文化的因素在文学领域的集中体现。因此,所谓“元和体”,显然并非仅是元稹和白居易的某种类型诗作的特指,而是包容着深广而丰富的时代性内涵。

关键词：唐代中期思想革新元和诗变元和体

城市轨道交通产业投资对当年投资乘数的影响研究——以湖南数据为例

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湖南大学学报（社会科学版） 2011年第5期25卷 69-74页

作者：徐宗祥中南大学商学院湖南长沙410083

不同的当年投资乘数对于经济增长的作用不同,因此,投资乘数的计算可以准确测量投资对经济增长的促进作用。通过计算湖南城市轨道交通产业投资对湖南当年投资乘数的影响,可以预测未来湖南的投资乘数及其经济增长。通过研究可以发现发展... 详细信息

不同的当年投资乘数对于经济增长的作用不同,因此,投资乘数的计算可以准确测量投资对经济增长的促进作用。通过计算湖南城市轨道交通产业投资对湖南当年投资乘数的影响,可以预测未来湖南的投资乘数及其经济增长。通过研究可以发现发展轨道交通产业不仅对湖南经济增长率有着现实贡献,而且能够通过投资乘数变化对总供给函数的影响,来延长发掘该产业对湖南经济增长潜在的未来的贡献。

关键词：城市轨道交通产业当年投资乘数边际消费倾向总供给函数

维普期刊数据库博看期刊

Effectiveness and safety of noninvasive positive-pressure ventilation for severe hypercapnic encephalopathy due to acute exacerbation of chronic obstructive pulmonary disease:a prospective case-control study

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Chinese Medical Journal 2007年第24期120卷 2204-2209页

作者： ZHU Guang-fa ZHANG Wei zong Hua xu Qiu-fen LIANG Ying Department of Respiratory Medicine Beijing Anzhen HospitalCapital Medical University Beijing 100029 China

Background Although severe encephalopathy has been proposed as a possible contraindication to the use of noninvasive positive-pressure ventilation （NPPV）, increasing clinical reports showed it was effective in patients with impaired consciousness and even coma secondary to acute respiratory failure, especially hypercapnic acute respiratory failure （HARF）. To further evaluate the effectiveness and safety of NPPV for severe hypercapnic encephalopathy, a prospective case-control study was conducted at a university respiratory intensive care unit （RICU） in patients with acute exacerbation of chronic obstructive pulmonary disease （AECOPD） during the past 3 years. Methods Forty-three of 68 consecutive AECOPD patients requiring ventilatory support for HARF were divided into 2 groups, which were carefully matched for age, sex, COPD course, tobacco use and previous hospitalization history, according to the severity of encephalopathy, 22 patients with Glasgow coma scale （GCS）〈10 served as group A and 21 with GCS 〉10 as group B. Results Compared with group B, group A had a higher level of baseline arterial partial CO2 pressure （（102±27） mmHg vs （74±17） mmHg, P〈0.01）, lower levels of GCS （7.5±1.9 vs 12.2±1.8, P〈0.01）, arterial pH value （7.18±0.06 vs 7.28±0.07, P〈0.01） and partial 02 pressure/fraction of inspired 02 ratio （168±39 vs 189±33, P〈0.05）. The NPPV success rate and hospital mortality were 73% （16/22） and 14% （3/22） respectively in group A, which were comparable to those in group B （68% （15/21） and 14% （3/21） respectively, all P〉0.05）, but group A needed an average of 7 cmH20 higher of maximal pressure support during NPPV, and 4, 4 and 7 days longer of NPPV time, RICU stay and hospital stay respectively than group B （P〈0.05 or P〈0.01）. NPPV therapy failed in 12 patients （6 in each group） because of excessive airway secretions （7 patients）, hemodynamic instability （2）, worsening of dyspnea and deterioration of gas exchange （2）, and gastric content aspiration （1）.

关键词： acute respiratory failure hypercapnia encephalopathy chronic obstructive pulmonary disease noninvasive positive pressure ventilation

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Ad hoc网络中DCF公平性分析与改进

电子与信息学报 2008年第2期30卷 472-476页

作者：雷磊许宗泽南京航空航天大学信息科学与技术学院南京210016

在考虑节点的物理载波检测范围大于通信范围的情况下,该文分析了多跳Adhoc网络中物理载波检测机制对IEEE 802.11DCF协议公平性的影响。针对载波干扰给IEEE802.11DCF协议带来的严重不公平问题,提出了一种基于冲突和干扰感知的退避(CIAB)... 详细信息

在考虑节点的物理载波检测范围大于通信范围的情况下,该文分析了多跳Adhoc网络中物理载波检测机制对IEEE 802.11DCF协议公平性的影响。针对载波干扰给IEEE802.11DCF协议带来的严重不公平问题,提出了一种基于冲突和干扰感知的退避(CIAB)算法。仿真证明,该算法能有效地改善IEEE802.11DCF协议的公平性,并且没有引起网络吞吐量的严重下降。

关键词： Ad hoc网络 DCF协议公平性物理载波检测机制