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3-D tunnel seismic advance prediction method with wide illumination and high-precision

Journal of Earth Science 2021年

作者： Peng Guan Cui–Fa Shao Yu–Yong Jiao Guo–Hua Zhang Jun–Peng Zou fei tan Faculty of Engineering， China University of Geosciences

Tunnel seismic advance prediction can effectively reduce the construction risk during tunnel excavation. Compared with the 2-D method， the 3-D method is more conducive to describing the spatial characteristics of the geological body by adding the seismic data in the vertical direction. However， some drawbacks still need improvement in the current 3-D tunnel seismic prediction method. 1) The geometry is complex， which is destructiveness， high cost， and time-consuming， and will delay the tunnel construction schedule. 2) Illumination of the anomalous body is insufficient， and the precision of migration imaging is low. 3) Shot points are far away from the tunnel face，the energy loss at the shot points is more serious. 4) The received signals at the tunnel wall have the surface wave with strong energy when the shot points are placed on the tunnel wall. 5) The geometry is notlinear， so the directional filtering method cannot be used to extract the reflection wave. To overcome the drawbacks of the current prediction method， this paper proposes a new 3-D symmetrical tunnel seismic prediction method. Six geophones are installed on the tunnel wall， two on the left side， two on the right side， and two on the top side. Twenty-four shot points are placed on the tunnel face and near both sides of the tunnel wall， twelve shot points on the left side and twelve shot points on the right side. The shot points will move along with the forward excavation of the tunnel. The wavefield analysis， illumination statistics， and 3-D reverse time migration imaging are used to evaluate the proposed method. The result of modeled data indicates that the proposed 3-D geometry has some advantages as following: 1) The geometry is simple and the geophone installation time is short. 2) It has high illumination energy， wide illumination range， and can improve the prediction distance and imaging accuracy. 3) The proposed 3-D method can better estimate the velocity of surrounding rock and is more conduciv

关键词： Geometry Illumination Migration Tunnel seismic advance prediction

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性别化的叙述声音——苏珊·S·兰瑟女性主义叙事学理论

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海南大学学报（人文社会科学版） 2018年第3期36卷 102-107页

作者：谭菲北京大学中国语言文学系北京100871

苏珊·S·兰瑟的女性主义叙事学理论将女性主义文评与叙事诗学结合,二者通过叙事诗学的概念叙述声音连结起来,从话语层面展现女性作者的意图,又从历史层面描述性别权威的压制,使得叙事学突破自身,加入了社会历史内涵,同时避免了女性主... 详细信息

苏珊·S·兰瑟的女性主义叙事学理论将女性主义文评与叙事诗学结合,二者通过叙事诗学的概念叙述声音连结起来,从话语层面展现女性作者的意图,又从历史层面描述性别权威的压制,使得叙事学突破自身,加入了社会历史内涵,同时避免了女性主义研究的泛化,但其实际的诠释效力仍有待商榷。

关键词：叙述声音女性主义叙事学苏珊·S·兰瑟《虚构的权威》

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Telomere-to-telomere carrot (Daucus carota) genome assembly reveals carotenoid characteristics

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Horticulture Research 2023年第7期10卷 112-124页

作者： Ya-Hui Wang Pei-Zhuo Liu Hui Liu Rong-Rong Zhang Yi Liang Zhi-Sheng Xu Xiao-Jie Li Qing Luo Guo-fei tan Guang-Long Wang Ai-Sheng Xiong State Key Laboratory of Crop Genetics&Germplasm Enhancement and Utilization Ministry of Agriculture and Rural Affairs Key Laboratory of Biology and Germplasm Enhancement of Horticultural Crops in East ChinaCollege of HorticultureNanjing Agricultural UniversityNanjingJiangsu 210095China Institute of Horticulture Guizhou Academy of Agricultural SciencesGuiyangGuizhou 550025China School of Life Science and Food Engineering Huaiyin Institute of TechnologyHuaianJiangsu 223003China Beijing Vegetable Research Center Beijing Academy of Agriculture and Forestry SciencesKey Laboratory of Biology and Genetic Improvement of Horticultural Crops in North ChinaBeijing 100097China

Carrot(Daucus carota)is an Apiaceae plant with multi-colored fleshy roots that provides a model system for carotenoid *** this study,we assembled a 430.40 Mb high-quality gapless genome to the telomere-to-telomere(T2T)level of“Kurodagosun”*** total,36268 genes were identified and 34961 of them were functionally *** proportion of repeat sequences in the genome was 55.3%,mainly long terminal *** on the coverage of the repeats,14 telomeres and 9 centromeric regions on the chromosomes were predicted.A phylogenetic analysis showed that carrots evolved early in the family *** on the T2T genome,we reconstructed the carotenoid metabolic pathway and identified the structural genes that regulate carotenoid *** the 65 genes that were screened,9 were newly ***,some gene sequences overlapped with transposons,suggesting replication and functional differentiation of carotenoid-related genes during carrot *** that some gene copies were barely expressed during development,they might be functionally *** of 24 cytochrome P450 genes associated with carotenoid biosynthesis revealed the tandem or proximal duplication resulting in expansion of CYP gene *** results provided molecular information for carrot carotenoid accumulation and contributed to a new genetic resource.

关键词： carrot sequences characteristics

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Improved Radio Network Dimensioning for Real-Time Polling Service on IEEE 802.16 Wireless Networks with QoS Consideration

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International Journal of Communications, Network and System Sciences 2012年第3期5卷 192-205页

作者： Thiaw Seng Ng Teong Chee Chuah Yi fei tan Faculty of Engineering Multimedia University Cyberjaya Malaysia

Recently, applications of real-time polling service (rtPS) in IEEE 802.16 wireless networks have gained considerable popularity. These applications generate large amounts of real time traffic in the network and thus maintaining the quality of service (QoS) such as packet delay requirement in rtPS dominant networks is critical. Existing dimensioning methodology does not consider QoS parameters of rtPS in network dimensioning. Moreover, exhaustive and time-consuming simulations are required to evaluate the performance and QoS of rtPS. To overcome this problem, we propose an improved radio network dimensioning framework which considers QoS parameters of rtPS in network dimensioning. In this framework, an analytical model is developed to evaluate the capacity and performance of rtPS in IEEE 802.16 wireless networks. The proposed framework provides a fast and accurate means of finding the trade-off between system load and packet delay, thus providing network operators with an analytical tool that jointly considers coverage, capacity and QoS requirements for obtaining the minimum number of sites required. The accuracy of the proposed model is validated through simulations.

关键词： IEEE802.16 Dimensioning Analytical Model Real Time Polling Service QoS

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A comparative study of influential factors correlating with early and late hypothyroidism after ^131I therapy for Graves＇ disease

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Chinese Medical Journal 2010年第12期123卷 1528-1532页

作者： WANG Ren-fei tan Jian ZHANG Gui-zhi MENG Zhao-wei ZHENG Wei Department of Nuclear Medicine Tianjin Medical University General Hospital Tianjin 300052 China

Background 131Ⅰ therapy is recognized as the simplest, safest, least expensive, and most effective treatment, and accepted by more and more patients. However its curative effect is influenced by many factors, therefore there are some difficulties for doctors to establish individual treatment strategy. The aims of this study were to determine the incidence of early and late hypothyroidism after 131Ⅰ treatment for Graves＇ disease （GD） and to compare their correlation, to observe and analyze the influential factors and to understand the predictabilities of *** Five hundred GD patients （144 males, 356 females; age （41.2±12.3） years） received 131Ⅰ treatment for the first time. The therapeutic procedure was carried out as the following： undergoing 131Ⅰ uptake test to obtain maximum of thyroid uptake value and effective half-life （EHL） time; estimating the thyroid＇s weight by ultrasonography; determination of thyroid hormones and correlative antibodies; pre-therapy physical examination; thyroid imaging; calculating 131Ⅰtherapeutic dosage; per os uptake of the determined 131Ⅰ dosage; follow-up appraisal of curative effect. The observing parameters included age, gender, thyroid weight, GD duration, condition of onset, state of disease, course of treatment, EHL time, maximum of thyroid uptake value, 131Ⅰ dosage and titer of correlative antibodies. We sorted out the data and used both univariate and multivariate analysis to evaluate them *** The incidence rates of early and late hypothyroidism were 33.2% and 6.6% respectively after 131Ⅰ treatment and approximately 22.2% cases of late hypothyroidism developed from early hypothyroidism. The influential factors of early hypothyroidism included course of GD, the highest thyroid uptake ratio of 131Ⅰ, EHL time and thyroid microsome antibody （TMAb）, etc. A multivariate analysis on late hypothyroidism showed that female patients, with recurrence after anti-thyroid drug treatment and higher thyroid weight, ha

关键词： Graves' disease ^131I therapy hypothyroidism effective half-life time thyroid microsome antibody

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试析电子文件存档所面临的挑战——基于档案的构成要素

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山西档案 2011年第4期 25-26页

作者：谭飞菲湖北大学历史文化学院 09研湖北武汉430062

当今的社会产生了大量的电子文件，它们本质上是属于档案的，它们的出现有一定的机遇，但无法逃避种种挑战，笔者试着从档案的构成要素这一视角来分析电子文件所面临的挑战。

关键词：电子文件存档档案要素

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Reconstruction of human embryos derived from somatic cells

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Chinese Science Bulletin 2003年第17期48卷 1840-1843页

作者： LU Changfu, LIN Ge, XIE Changqing, GONG fei, ZHOU Hong, tan Yueqiu & LU Guangxiu Institute of Reproduction and Stem Cell Engineering of South University, Changsha, Hunan 410078, China Institute of Reproduction and Stem Cell Engineering of South University Hunan China

Reconstruction of human nuclear transfer em-bryos is a necessary step of therapeutic cloning. In this study we injected somatic cell nuclei into MⅡ oocytes and acti-vated reconstructed oocytes with calcium ionophore A23187 (CaA) and 6-dimethylaminopurine (6-DMAP). After oocyte activation and 2PN formation, we removed the female PN. By using this method, we avoided the application of DNA fluorescent stain and ultraviolet light for oocyte enucleation, and over elimination of ooplasm was also mitigated. Some reconstructed embryos developed into the blastocyst stage in vitro.

关键词：人体细胞胚胎干细胞细胞核移植晶胚钙离子载体卵母细胞

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基于视觉传达特性的激光散斑移动速度规律分析与研究

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激光杂志 2020年第2期41卷 64-67页

作者：谈飞湖北第二师范学院

采用激光散斑检验非正视眼光焦度是一种简便、精准的验光方式,因此,基于视觉传达特性分析激光散斑移动速度规律、视觉特征匹配构建激光散斑图像参考子区与目标子区相似程度相关函数以及优化函数得到视觉激光散斑图像;据此构建激光散斑... 详细信息

采用激光散斑检验非正视眼光焦度是一种简便、精准的验光方式,因此,基于视觉传达特性分析激光散斑移动速度规律、视觉特征匹配构建激光散斑图像参考子区与目标子区相似程度相关函数以及优化函数得到视觉激光散斑图像;据此构建激光散斑视觉光路,计算散斑在人眼视网膜中移动的视觉速度,得到Fresnel激光散斑移动速度规律分析结果:条件一中,远视眼观察的激光散斑为顺动,激光散斑移动速度和远视程度成反比;条件二中,远视眼观察的激光散斑为逆动,激光散斑移动速度和远视程度成正比;激光散斑图像与视网膜间长度小于0的近视眼观察到的激光散斑为顺动,移动速度和近视程度成正比。经验证,测试结果与上述研究方法得出的激光散斑移动速度规律一致,研究方法有效性得以验证。

关键词：视觉传达视觉特征激光散斑移动速度规律分析

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Fabrication of Negative Charged Poly(Ethylene glycol)-diacrylate Hydrogel as a Bone Tissue Engineering scaffold

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世界最新医学信息文摘 2016年第18期16卷 1-4页

作者： WANG Ya-qi LIU Jie tan fei XIE Wei Department of Prosthodontics The affiliated hospital of Qingdao universityQingdao University

Objective To improve the cell attachment of PEGDA hydrogel,the SMAS small molecule was used to modify the PEGDA *** charged hydrogel would show improved cell attachment and enhanced protein adsorption caused by enhancement of electrostatic *** In this study,a series of charged hydrogels were produced by adding different concentrations of charged small molecule monomer into the PEGDA ***,we investigate the physicochemical and biological characteristics of charged hydrogels,including FTIR,swelling ratio,contact angle,cell *** The results indicate that the charged monomer had been successfully incorporated into PEGDA ***,the protein adsorption of the hydrogel increased with increasing concentration of charge ***,compared to PEGDA hydrogel,the cell attachment significantly improved on the charged *** The charged hydrogel would be a promising scaffold candidate for bone tissue engineering.

关键词： Tissue engineering Charged hydrogel Charge

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AgMYB1,an R2R3-MYB factor,plays a role in anthocyanin production and enhancement of antioxidant capacity in celery

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Vegetable Research 2021年第1期1卷 2-13页

作者： Kai Feng Guo-Ming Xing Jie-Xia Liu Hao Wang Guo-fei tan Guang-Long Wang Zhi-Sheng Xu Ai-Sheng Xiong State Key Laboratory of Crop Genetics and Germplasm Enhancement Ministry of Agriculture and Rural Affairs Key Laboratory of Biology and Germplasm Enhancement of Horticultural Crops in East ChinaCollege of HorticultureNanjing Agricultural University1 WeigangNanjing 210095China Collaborative Innovation Center for Improving Quality and Increase Profits of Protected Vegetables in Shanxi Shanxi Agricultural UniversityTaigu 030801China Institute of Horticulture Guizhou Academy of Agricultural SciencesGuiyang 550006China School of Life Science and Food Engineering Huaiyin Institute of TechnologyHuaian 223001China College of Horticulture and Plant Protection Yangzhou UniversityYangzhou 225009China

Celery is rich in nutrients and cultivated *** are natural plant pigments with high antioxidant capabilities in the human *** accumulation of anthocyanins in celery results in the purple skin color of ***,an R2R3-MYB transcription factor(TFs),AgMYB1,was cloned from purple-skin *** analysis revealed that AgMYB1 belongs to the anthocyanin *** alignment showed that AgMYB1 contains multiple anthocyanin-related *** with the activating role in anthocyanin production,AgMYB1 showed higher transcriptions in purple celery compared with non-purple *** expression of AgMYB1 in tobacco leaves promoted the accumulation of anthocyanins and produced red pigments in *** expression of AgMYB1 in Arabidopsis activates anthocyanin production and generates dark-purple *** enhancement of anthocyanin biosynthetic genes transcripts and glycosylation capacities in transgenic Arabidopsis verified the activating roles of AgMYB1 at the gene and protein level,*** antioxidant capacity of transgenic Arabidopsis was also increased compared to wild type ***,yeast two-hybrid assay proved that AgMYB1 interacted with bHLH TFs to regulate anthocyanin *** results show that the overexpression of single R2R3-MYB gene,AgMYB1,without coexpression of other TFs,can improve anthocyanin production and antioxidant capacity in transgenic *** study presents new information for anthocyanin regulatory mechanisms in purple celery and provides a strategy for cultivating plants with high levels of anthocyanins.

关键词： anthocyanin purple branch

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