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Late Mesozoic tectonostratigraphic division and correlation of the Bohai Bay basin: Implications for the Yanshanian Orogeny

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Science China Earth Sciences 2019年第11期62卷 1783-1804页

作者： Jichang ZHU Youliang FENG Qing-Ren MENG Fengcheng WU Hao LI Haitao LIU Feipeng ZHANG Tianyu WANG Guoli WU Caineng ZOU Rixiang ZHU Institute of Geology and Geophysics CASBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Innovation Academy for Earth Science CASBeijing 100029China PetroChina Research Institute of Petroleum Exploration and Development Beijing 100083China Institute of Sinopec Exploration and Development Research Beijing 100083China School of Geosciences China University of PetroleumQingdao 266580China

We present the results of Mesozoic sequences of the Bohai Bay basin in North China, based mainly on geochronology and interpretations of seismic profiles and logging data. Five tectono-stratigraphic sequences are defined: Lower-Middle Triassic, Lower-Middle Jurassic, Upper Jurassic, Lower Cretaceous and Upper Cretaceous. Based on an analysis of detrital zircons, the clastic rocks recorded two intervals of Jurassic magmatic activity, during 180–175 and 160–152 Ma, which can be correlated to the Nandaling and Tiaojishan Formations in the Yanshan area, respectively. However, since Jurassic volcanic rocks have not yet been found in the Bohai Bay basin, we speculate that these two stages of activity were mainly concentrated around the periphery of the North China Craton(NCC) rather than within. Based on an analysis of zircons from volcanic rocks and pyroclastics, the early Cretaceous magmatism in the Bohai Bay basin can be divided into two stages, 125–120 and 110–100 Ma,which can be correlated to magmatism in the eastern part of the NCC. The zircon ages indicate an absence of volcanic activity during the late Tuchengzi and Zhangjiakou periods which may correlate to the uplift of the Bohai Bay basin in the late Late Jurassic. Comparison of the development of Mesozoic basins and sedimentary strata in the central-eastern part of Yanshan tectonic belt and the the Bohai Bay basin indicates that the two areas are generally comparable, but with substantial differences.The central-eastern part of the Yanshan structural belt lacks Early-Middle Triassic strata, and the Bohai Bay basin lacks late Jurassic-early Cretaceous strata. Based on research results from late Mesozoic sedimentary structures in the central and eastern parts of the Yanshan tectonic belt, we infer that episode A of the Yanshanian Orogeny was weak in the Bohai Bay basin and its periphery, while episode B of the Yanshanian Orogeny had a strong influence on the Bohai Bay basin and its periphery. The available data reveal differences in the expression of these ep

关键词： Yanshanian Orogeny Late Mesozoic Central-eastern part of Yanshan tectonic belt The Bohai Bay basin Tectonostratigraphic division

Weakly-coupled mode division multiplexing over conventional multi-mode fiber with intensity modulation and direct detection

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Frontiers of Optoelectronics 2019年第1期12卷 31-40页

作者： Juhao LI Zhongying WU Dawei GE Jinglong ZHU Yu TIAN Yichi ZHANG Jinyi YU Zhengbin LI Zhangyuan CHEN Yongqi HE State Key Laboratory of Advanced Optical Communication Systems and Networks Peking UniversityBeijing 100871China Wuhan Research Institute of Posts and Telecommunications Wuhan 430074China

Multi-mode fiber(MMF)links are expected to greatly enhance capacity to cope with rapidly increasing data traffic in optical short-reach systems and networks.Recently,mode division multiplexing(MDM)over MMF has been proposed,in which different modes in MMF are utilized as spatial channels for data transmission.Stronglycoupled MDM techniques utilizing coherent detection and multiplex-input-multiplex-output(MIMO)digital signal processing(DSP)are complex and expensive for shortreach transmission.So the weakly-coupled approach by significantly suppressing mode coupling in the fiber and optical components has been proposed.In this way,the signals in each mode can be independently transmitted and received using conventional intensity modulation and direct detection(IM-DD).In this paper,we elaborate the key technologies to realize weakly-coupled MDM transmission over conventional MMF,including mode characteristic in MMF and weakly-coupled mode multiplexer/ demultiplexer(MUX/DEMUX).We also present the upto-date experimental results for weakly-coupled MDM transmission over conventional OM3 MMF.We show that weakly-coupled MDM scheme is promising for high-speed optical interconnections and bandwidth upgrade of already-deployed MMF links.

关键词： multi-mode fiber (MMF) mode division multiplexing (MDM) weak mode coupling intensity modulation and direct detection (IM-DD)

MicroRNA-15a-cell division cycle 42 signaling pathway in pathogenesis of pediatric inflammatory bowel disease

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World Journal of Gastroenterology 2018年第46期24卷 5234-5245页

作者： Wen-Juan Tang Kai-Yue Peng Zi-Fei Tang Yu-Huan Wang Ai-Juan Xue Ying Huang Department of Gastroenterology Children’s Hospital of Fudan University

AIM To determine whether cell division cycle(Cdc)42 is regulated by microRNA(miR)-15 a in the development of pediatric inflammatory bowel disease(IBD).METHODS We cultured 293 T cells, used plasmids and performed dual-luciferase assay to determine whether Cdc42 is a miR-15 a target gene. We cultured Caco-2 cells, and stimulated them with tumor necrosis factor(TNF)-α. We then employed lentiviruses to alter the expression of miR-15 a and Cdc42. We performed quantitative reverse transcription polymerase chain reaction(qRTPCR) and immunofluorescence to determine whether Cdc42 is regulated by miR-15 a in Caco-2 cells. Finally, we collected ileocecal tissue by endoscopy from patients and performed qRT-PCR to examine the expression of miR-15 a and Cdc42 in pediatric IBD patients.RESULTS Target Scan and dual-luciferase assay revealed thatCdc42 was a miR-15 a target gene. MiR-15 a expression increased(P = 0.0038) and Cdc42 expression decreased(P = 0.0013) in cells stimulated with TNF-α, and the expression of the epithelial junction proteins zona occludens(ZO)-1(P < 0.05) and E-cadherin(P < 0.001) decreased. Cdc42 levels decreased in miR-15 a-mimic cells(P < 0.001) and increased in miR-15 a inhibitor cells(P < 0.05). ZO-1 and E-cadherin decreased in mi R-15 a-mimic cells(P < 0.001) but not in the miR-15 a inhibitor + TNF-α cells. In Lv-Cdc42 + TNF-α cells, ZO-1 and E-cadherin expression increased compared to the Lv-Cdc42-NC + TNF-α(P < 0.05) or miR-15 a-mimic cells(P < 0.05). Fifty-four pediatric IBD patients were included in this study, 21 in the control group, 19 in the Crohn's disease(CD) active(AC) group, seven in the CD remission(RE) group, and seven in the ulcerative colitis(UC) group. MiR-15 a increased and Cdc42 decreased in the CD AC group compared to the control group(P < 0.05). miR-15 a decreased and Cdc42 increased in the CD RE group compared to the CD AC group(P < 0.05). miR-15 a was positively correlated with the Pediatric Crohn's disease Activity Index(PCDAI)(P = 0.006), while Cdc42 was negatively correlated

关键词： Pediatric inflammatory bowel disease MicroRNA-15a Cell division cycle 42 Zona occludens-1 E-cadherin

QSM-IDM -A novel quadrature spatial modulation based on interleaving division multiplexing for multiple antenna system

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Digital Communications and Networks 2019年第3期5卷 183-188页

作者： Sherif K. El Dyasti Esam A.A. Hagras Hadia El-Hennawy Ain Shams Cairo Egypt Elec and Comm. Dept Technical Research Centre Cairo Egypt Faculty of Engineering Ain Shams Cairo Egypt

Quadrature Spatial Modulation (QSM) is a high spectral efficiency Multiple-Input Multiple Output (MIMO) technique used to improve the spectral efficiency of wireless communication systems. The main concept of QSM is to extend the spatial constellation of the conventional Spatial Modulation (SM) in both the in-phase and quadrature components of the data symbol. In this paper, because QSM-based on Interleaxdng division Multiplexing (IDM) has not been introduced in the literature as a multiple antenna system, we introduced a novel scheme, called QSM system based on Interleaving division Multiplexing (QSM-IDM). The antenna sets are also applied to a spreader, before being used to assign an antenna number for information transmission. Analysis and simulations for a flat fading channel show that the proposed QSM-IDM method significantly outperforms the original QSM system with the same data rate, while maintaining a relatively acceptable complexity. The obtained simulation results show that the conducted analysis yields significant improvements for the accuracy of the proposed scheme, with satisfactory complexity.

关键词： Interleaver division Multiplexing (IDM) Multiple Input Multiple Output (MIMO) Spatial Modulation (SM) Quadrature Spatial Modulation (QSM)

Groundwater System division and Description of Asia

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Acta Geologica Sinica(English Edition) 2016年第4期90卷 1434-1443页

作者： ZHANG Fawang YI Qing CHENG Yanpei YUE Chen DONG Hua Institute of Karst Geology Chinese Academy of Geological Sciences Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological Sciences

Based on landform, climate, river system, geological structure and hydrogeological structure and from the perspective of systematology, the groundwater system of Asia can be divided into 36 secondary groundwater systems under 11 primary ones by the intercontinental scale. This forms part of the work of the groundwater series map of Asia, which is compiled according to groundwater system division and evaluation of the total amount and types of aquifer, reflecting the large-scale features of groundwater resources in Asia. Systematic profiling of groundwater in this way provides a scientific basis for groundwater exploitation planning and management in Asia, and avoiding disputes over groundwater resources and the environment among Asian countries.

关键词： Asia groundwater system climate and topography division

改进的多输人多输出正交频分复用水声通信判决反馈信道估计算法

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声学学报 2016年第1期41卷 94-104页

作者：乔钢王巍刘凇佐 Rehan Khan 王玥哈尔滨工程大学水声技术国家级重点实验室哈尔滨150001

针对最小均方误差准则下(Minimum Mean Square Error,MMSE)判决反馈信道估计算法在多输入多输出正交频分复用(Multiple-input Multiple-output Orthogonal Frequency division Multiplexing,MIMO-OFDM)低信噪比水声通信环境下存在误码遗传缺陷,提出了一种基于压缩感知理论的改进的MMSE判决反馈信道估计算法。通过结合浅海水声信道的稀疏性特点,利用编码校验后的信息与原始信息实现了对信道估计的判决反馈更新,采用匹配追踪算法改进MMSE判决反馈追踪信道估计技术,实现了抑制传统判决反馈信道估计算法在迭代更新及传递过程中存在的误码遗传的目的。仿真和水池实验结果证实:改进的MMSE判决反馈追踪信道估计算法不仅可以有效的抑制误码遗传,对抗突发噪声,跟踪信道的缓慢时变,同时大幅降低了导频占用率,提高了通信质量。

关键词：多输入多输出正交频分复用信道估计算法判决反馈水声通信多输入多输出最小均方误差准则 division 遗传缺陷

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正交频分复用无源时间反转信道均衡方法研究

声学学报 2015年第3期40卷 469-476页

作者：尹艳玲乔钢刘凇佐哈尔滨工程大学水声技术重点实验室哈尔滨150001 哈尔滨工程大学水声工程学院哈尔滨150001

针对水声信道多途信号引起的正交频分复用(Orthogonal Frequency division Multiplexing,OFDM)水声通信系统符号间干扰的问题,提出了无源时间反转均衡的方法,将发送的探测信号时间反转与OFDM信号做卷积,利用无源时间反转镜的时间聚焦原... 详细信息

针对水声信道多途信号引起的正交频分复用(Orthogonal Frequency division Multiplexing,OFDM)水声通信系统符号间干扰的问题,提出了无源时间反转均衡的方法,将发送的探测信号时间反转与OFDM信号做卷积,利用无源时间反转镜的时间聚焦原理减小信道多途带来的符号间干扰,在OFDM符号中不使用导频的情况下实现信道均衡,简化了均衡步骤并提高了OFDM符号频带利用率。分析比较了无源时反均衡方法与最小平方信道均衡在水声多途信道下的误码性能。仿真研究和湖上实验表明,无源时反信道均衡算法可以有效的减小多途信道对OFDM水声通信系统带来的影响。

关键词：时间反转镜正交频分复用水声信道均衡方法无源 OFDM信号 division 符号间干扰

Newly elected members of the Chinese Academy of Sciences(chemistry division)in 2023

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Aggregate 2023年第6期4卷 3-7页

作者： [Anonymous]

In November 2023,the Chinese Academy of Sciences(CAS)announced the newly elected members.In this Profile col-umn,we introduce 10 Chinese and five foreign members in the chemistry division of the CAS.Congratulations to... 详细信息

关键词： chemistry division Academy

Time division Multiplexing Fiber Bragg Grating Sensor System Using Composite Codes

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Journal of Donghua University(English Edition) 2019年第2期36卷 163-169页

作者：曹瑶煜徐弘萱张洋朱雨霜桂林左健存 School of Environmental and Materials Engineering Shanghai Polytechnic UniversityShanghai 201209China Merchant Marine College Shanghai Maritime UniversityShanghai 201306China School of Computer and Information Engineering Shanghai Polytechnic UniversityShanghai 201209China

A novel multi-point sensing scheme to improve the signal-to-noise ratio(SNR),temperature measurement range of the fiber Bragg grating(FBG)sensors is proposed.The new sensing scheme adopted a composite coding technique based on Simplex codes and Golay codes and time division multiplexing technique to enhance the performance of the sensing system.Simulation results,in good agreement with the theory,confirmed that the maximum SNR enhancement of the sensor system employing composite coding based on 15-bit Simplex codes and 16-bit Golay codes was approximately 6.01 dB in comparison to the conventional single pulse case.

关键词： fiber Bragg grating(FBG) time division multiplexing(TDM) composite coding scheme coding gain