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Phase noise approximation analysis for the OFDM system

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 95-98,107页

作者： tang Jing SHEN Shu-qun Wireless Technique Innovation Institute Key Laboratory of UniversalWireless Communication Ministry of Education Beijing University of Postsand Telecommunications Beijing 100876 China

The influence of phase noise（PN） present at the access point（AP） and mobile terminator（MT） may degrade the performance in orthogonal frequency division multiplexing （OFDM） system, because the OFDM system is sensitive to the PN. The method of PN approximation based on the PN power spectrum was proposed to combat the influence of the PN present. The idea of the PN cancellation is the PN is approximated for the sum of the different frequency between the AP and the MT as well as Doppler shift supposing that the fixed different frequency during several OFDM symbols are identical, so the variable phase may be considered as the combination of the fixed partition and the random partition. The approximation method is utilized to remove the fixed and the random phase partition so that the signal-to-noise ratio （SNR） may be improved. The analysis and the simtilation proposed show that the method may effectively improve the performance of the OFDM system.

关键词： inter-carrier interference(ICI) phase noise cancellation common phase error (CPE)

ABORTED GAMETOPHYTE 1 is required for gametogenesis in Arabidopsis

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Journal of Integrative Plant Biology 2015年第12期57卷 1003-1016页

作者： hong-Hui Cui hong-Ze Liao Yu tang Xin-Yu Du Li-qun Chen De Ye Xue-Qin Zhang State Key Laboratory of Plant Physiology and Biochemistry College of Biological Sciences China Agricultural University

In flowering plants, the male and female gameto- genesis is a crucial step of sexual reproduction. Although many genes have been identified as being involved in the gametogenesis process, the genetic mechanisms underlying gametogenesis remains poorly understood. We reported here characterization of the gene, ABORTED GAMETOPHYTE 1 （AOGI） that is newly identified as essential for gametogenesis in Arabidopsis thaliana. AOG1 is expressed predominantly in reproductive tissues including the developing pollen grains and ovules. The AOG1 protein shares no significant amino acid sequence similarity with other documented proteins and is located mainly in nuclei of the cells. Mutation in AOG~ caused degeneration of pollen at the uninucleate microspore stage and severe defect in embryo sacs, leading to a significant reduction in male and female ***, the molecular analyses showed that the aogl mutant significantly affected the expression of several genes, which are required for gametogenesis. Our results suggest that AOG1 plays important roles in gameto- genesis at the stage prior to pollen mitosis 1 （PMI） in Arabidopsis, possibly through collaboration with other genes.

关键词： Arabidopsis embryo sacs gametogenesis pollen grains

激光冲击TC4钛合金材料本构模型参数的修正方法

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机械工程与自动化 2024年第2期 64-65,68页

作者：吴小燕苏超群汤洋葛茂忠吴清源张永康中国航发南方工业有限公司湖南株洲412002 广东工业大学机电工程学院广东广州510006 江苏理工学院材料工程学院江苏常州213001

为了更准确地预测激光冲击强化TC4钛合金表层残余应力分布,通过试验和数值模拟相结合的方法对Johnson-cook(J-C)本构模型参数进行了修正。研究结果表明:修正后的J-C模型提高了激光冲击强化TC4钛合金表层残余应力的仿真精度。

关键词： TC4钛合金激光冲击强化数值模拟 J-C本构模型

女性盆底功能障碍性疾病诊治流程及物理康复技术临床应用--临床评估与诊断

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生殖医学杂志 2024年第4期33卷 419-426页

作者：刘盼沈彩娥唐桂艳王南竹李海燕汪利群郑州大学第二附属医院妇产科郑州450014 苏州市妇幼保健院苏州215004 桂林医学院第二附属医院桂林541199 长春中医药大学附属医院长春130021 江苏省盆底康复工程技术研究中心南京210000 江西省妇幼保健院南昌330077

女性盆底功能障碍性疾病(FPFD)是主要由于盆底支持缺陷、损伤、退化等导致盆腔器官发生移位或功能紊乱而引起的一系列病症,往往与肌肉、结缔组织、筋膜、神经和血管等一种或多种功能异常有关,每种类型FPFD的发生机制复杂,病因不一,两种... 详细信息

女性盆底功能障碍性疾病(FPFD)是主要由于盆底支持缺陷、损伤、退化等导致盆腔器官发生移位或功能紊乱而引起的一系列病症,往往与肌肉、结缔组织、筋膜、神经和血管等一种或多种功能异常有关,每种类型FPFD的发生机制复杂,病因不一,两种及以上类型的FPFD往往同时出现。系统而全面的评估有助于了解疾病发生原因及为患者制定综合治疗方案提供依据。本章节以尿失禁和盆腔器官脱垂为例,重点阐述系统性临床评估内容。

关键词：女性盆底功能障碍性疾病尿失禁盆腔器官脱垂临床评估临床诊断

Efficacy of inactivated SARS-CoV-2 vaccination in pediatric hematology/oncology patients:a real-world study

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World Journal of Pediatrics 2023年第10期19卷 1017-1021页

作者： Jing Miao Jing-Ying Zhang Juan Liang Fen-Ying Zhao Hua Song Wei-qun Xu Yong-Min tang Xiao-Jun Xu Qiang Shu Children’s Hospital Zhejiang University School of MedicineHangzhou 310052China National Clinical Research Center for Child Health HangzhouChina

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has been spreading globally since its initial outbreak in *** evidence has revealed that children who are receiving antitumor therapy or hematopoietic stem cell transplantation(HSCT)present higher rates of severe illness and mortality[1].It is important to identify infected children with hematology and oncology diseases who have the tendency to develop worse outcomes of coronal virus disease 2019(COVID-19)during the early stage of *** studies have demonstrated that vaccination against SARS-CoV-2 in adults can reduce the likelihood of infection and reduce the severity and mortality of COVID-19 when SARS-CoV-2 breakthrough infection occurs[2,3,4].However,the effectiveness of SARS-CoV-2 vaccination in children with hematology and oncology diseases is poorly defined due to the lack of relevant data,which might lead to vaccine hesitancy[5,6].

关键词： vaccination mortality respiratory

Dynamic mechanical characteristics of NdFeB in electromagnetic brake

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Defence Technology（防务技术） 2023年第1期19卷 111-125页

作者： Lei Li Guo-lai Yang Li-qun Wang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094JiangsuChina

With the continuous development of artillery,the disadvantages of hydraulic recoil brakes gradually *** the same time,the appearance of high-performance Nd Fe B permanent magnet makes it possible to apply electromagnetic braking technology to recoil *** this paper,prototype tests of a certain artillery were carried out to verify the feasibility of the electromagnetic brake(EMB)and obtain the electromagnetic braking *** to the brittleness of Nd Fe B,in order to eliminate the worry about the safety of EMB,SHPB experiments of Nd Fe B were carried ***,based on the assumption of uniform crack distribution,the law of crack propagation and damage accumulation was described theoretically,and the damage constitutive model suitable for brittle materials was proposed by combining the Zhu-Wang-tang(ZWT)***,the numerical simulation model of the artillery prototype was established and through calculation,the dynamic mechanical characteristics of Nd Fe B in the prototype were *** calculation results show that the strength of Nd Fe B can meet the requirements of the use in the working *** the perspective of damage factor,the damage value of the permanent magnet on the far right is larger,and the damage value of the inner ring gradually decreases to the outer ring.

关键词： Electromagnetic brake Sintered NdFeB Damage constitutive Dynamic mechanical characteristics

Caspase-3介导的细胞凋亡与细胞焦亡在肝细胞癌的作用及其中药治疗的研究进展

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现代中医药 2024年第4期44卷 1-6页

作者：郑美娥熊彦凌康徐瑞唐群廖海燕孟斌黎湘黄雷湖南中医药大学湖南长沙410208 湖南中医药大学第一附属医院湖南长沙410007

细胞凋亡与细胞焦亡是两种重要的程序性细胞死亡方式,而半胱氨酸蛋白酶-3(Caspase-3)在这两种死亡方式中都扮演着重要的角色,其参与了内源性、外源性途径介导的细胞凋亡以及Caspase-3/GSDME依赖性细胞焦亡,在肝细胞癌(hepatocellular ca... 详细信息

细胞凋亡与细胞焦亡是两种重要的程序性细胞死亡方式,而半胱氨酸蛋白酶-3(Caspase-3)在这两种死亡方式中都扮演着重要的角色,其参与了内源性、外源性途径介导的细胞凋亡以及Caspase-3/GSDME依赖性细胞焦亡,在肝细胞癌(hepatocellular carcinoma, HCC)的治疗中起到了至关重要的作用。近年来,通过Caspase-3介导细胞凋亡及细胞焦亡治疗肝细胞癌的中药研究文献不断增加,在为肝细胞癌治疗提供思路方面具有巨大潜力。文章就Caspase-3介导的细胞凋亡与焦亡在肝细胞癌的作用及其在中药治疗方面的研究成果作一综述,以期为肝细胞癌的治疗和药物研究提供帮助。

关键词： Caspase-3 细胞凋亡细胞焦亡肝细胞癌中药

Transformations of particles, metal elements and natural organic matter in different water treatment processes

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Journal of Environmental Sciences 2007年第3期19卷 271-277页

作者： YAN Ming-quan WANG Dong-sheng SHI Bao-you WEI qun-shan QU Jiu-hui tang hong-xiao State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Characterizing natural organic matter （NOM）, particles and elements in different water treatment processes can give a useful information to optimize water treatment operations. In this article, transformations of particles, metal elements and NOM in a pilot-scale water treatment plant were investigated by laser light granularity system, particle counter, glass-fiber membrane filtration, inductively coupled plasma-optical emission spectroscopy, ultra filtration and resin absorbents fractionation. The results showed that particles, NOM and trihalomethane formation precursors were removed synergistically by sequential treatment of different processes. Preozonation markedly changed the polarity and molecular weight of NOM, and it could be conducive to the following coagulation process through destabilizing particles and colloids; mid-ozonation enhanced the subsequent granular activated carbon （GAC） filtration process by decreasing molecular weight of organic matters. Coagulation-flotation and GAC were more efficient in removing fixed suspended solids and larger particles; while sand-filtration was more efficient in removing volatile suspended solids and smaller particles. Flotation performed better than sedimentation in terms of particle and NOM removal. The type of coagulant could greatly affect the performance of coagulation-flotation. Pre-hydrolyzed composite coagulant （HPAC） was superior to FeCl3 concerning the removals of hydrophobic dissolved organic carbon and volatile suspended solids. The leakages of flocs from sand-filtration and microorganisms from GAC should be mitigated to ensure the reliability of the whole treatment system.

关键词： flotation fixed suspended solid trihalomethane formation potential ultra filtration resin absorbent fractionation

Analysis on Dissociation of Pyramidal I Dislocation in Magnesium by Generalized-Stacking-Fault Energy

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Acta Metallurgica Sinica(English Letters) 2015年第7期28卷 876-882页

作者： qun Zu Ya-Fang Guo Xiao-Zhi tang Institute of Engineering Mechanics Beijing Jiaotong University

The generalized-stacking-fault energies are calculated to illustrate the dissociation of〈c＋a〉dislocation on pyramidal I plane in *** c surfaces of {1011} plane and its adjacent planes {3034} and {3032} are presented using Liu embedded-atom-method potential method,and one possible dissociation path of 1/3{1123} dislocation on {1011} plane with minimum energy is ***,another two reasonable dissociation paths of 1/3{1123} dislocation successively on {3034} and {3032} planes are also ***,based on molecular dynamics simulations of magnesium single crystals under c-axis compression,the possible slip path is further examined and discussed.

关键词： Generalized-stacking-fault energies (GSFEs) Molecular dynamics (MD) 〈c + a〉 slip Dissociation Magnesium