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RAYDATA总部办公室

现代装饰 2020年第7期 140-145页

作者： fei tang precht(设计) Chun Chen(设计) Zizhi Yu(设计) Chengcheng Liu(设计) Yanyan Gu(设计) Mei Li(设计) Chris precht(设计) CreatARimages(摄影) 舒禹(编译) 不详

RayData是一家对城市数据进行整合和可视化的公司,其北京总部位于由SOM设计事务所进行设计的保利国际广场。RayData总部办公室位于椭圆形摩天大楼的19层,并邀请了奥地利建筑工作室Studio precht进行室内设计。设计团队所打造的空间融合... 详细信息

RayData是一家对城市数据进行整合和可视化的公司,其北京总部位于由SOM设计事务所进行设计的保利国际广场。RayData总部办公室位于椭圆形摩天大楼的19层,并邀请了奥地利建筑工作室Studio precht进行室内设计。设计团队所打造的空间融合了建筑物本身的两个独特特征:椭圆形用于营造内部柔和感,菱形外墙启发了该空间的折线形布局。

关键词：设计事务所空间融合建筑工作室室内设计折线形摩天大楼办公室设计团队

Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第01期 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

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Numerical and experimental study on the critical velocity and smoke maximum temperature in the connected area of branch tunnel

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Building Simulation 2022年第4期15卷 525-536页

作者： Haihang Li fei tang Safety Engineering Institute College of Quality and Safety EngineeringChina Jiliang UniversityHangzhouChina State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei230026China

The objective of this study is to investigate critical velocity and smoke maximum temperature beneath the ceiling in the connected area of branch tunnel with varying fire *** fire sources were located in the divergent connected area of the branch tunnel,to imitate traffic accidents near the branch point.A 1/20 scale model branch tunnel was built including main line before branch,main line after branch,and *** tests and numerical simulations were performed to explore smoke movement characteristics with longitudinal *** results showed that the enlarged cross-sectional area in branch tunnel caused the shortening of the back-layering length,and a modified model of back-layering length was *** higher tunnel height in this work affected the critical condition of large fire;it caused a larger transition point of dimensionless critical velocity.A revised model was proposed for the maximum temperature rise of tunnel fires in the connected area of branch *** critical velocity kept unchanged when the branch angle increased from 0°to 20°because there is little change in the longitudinal smoke *** the local tunnel width of fire source was increased,the required critical velocity was increased while the local effective velocity kept nearly the same.

关键词： tunnel fire critical velocity maximum temperature dimensionless back-layering length branch tunnel

Liquid Water Path Retrieval Using the Lowest Frequency Channels of Fengyun-3C Microwave Radiation Imager(MWRI)

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Journal of Meteorological Research 2017年第6期31卷 1109-1122页

作者： fei tang Xiaolei ZOU Joint Center of Data Assimilation for Research and Application College of Atmospheric ScienceNanjing University of Information Science &Technology State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological Administration Earth System Science Interdisciplinary Center University of Maryland College Park

The Microwave Radiation Imager （MWRI） on board Chinese Fengyun-3 （FY-3） satellites provides measurements at 10.65, 18.7, 23.8, 36.5, and 89.0 GHz with both horizontal and vertical polarization channels. Brightness temperature measurements of those channels with their central frequencies higher than 19 GHz from satellite-based microwave imager radiometers had traditionally been used to retrieve cloud liquid water path （LWP） over ocean. The results show that the lowest frequency channels are the most appropriate for retrieving LWP when its values are large. Therefore, a modified LWP retrieval algorithm is developed for retrieving LWP of different magnitudes involving not only the high frequency channels but also the lowest frequency channels of FY-3 MWRI. The theoretical estimates of the LWP retrieval errors are between 0.11 and 0.06 mm for 10.65- and 18.7-GHz channels and between 0.02 and 0.04 mm for 36.5- and 89.0-GHz channels. It is also shown that the brightness temperature observations at 10.65 GHz can be utilized to better retrieve the LWP greater than 3 mm in the eyewall region of Super Typhoon Neoguri （2014）. The spiral structure of clouds within and around Typhoon Neoguri can be well captured by combining the LWP retrievals from different frequency channels.

关键词： microwave remote sensing Fengyun-3C Microwave Radiation Imager (MWRI) liquid water path (LWP) retrieval

Privacy-preserving authentication scheme based on zero trust architecture

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Digital Communications and Networks 2024年第5期10卷 1211-1220页

作者： fei tang Chunliang Ma Kefei Cheng College of Computer Science and Technology Chongqing University of Posts and Telecommunications School of Cyber Security and Information Law Chongqing University of Posts and Telecommunications

Zero trust architecture is an end-to-end approach for server resources and data security which contains identity authentication,access control,dynamic evaluation,and so *** work focuses on authentication technology in the zero trust *** this paper,a Traceable Universal Designated Verifier Signature(TUDVS) is used to construct a privacy-preserving authentication scheme for zero trust ***,when a client requests access to server resources,we want to protect the client's access privacy which means that the server administrator cannot disclose the client's access behavior to any third *** addition,the security of the proposed scheme is proved and its efficiency is ***,TUDVS is applied to the single packet authorization scenario of the zero trust architecture to prove the practicability of the proposed scheme.

关键词： Zero trust architecture Privacy-preserving Authentication Anonymity revocation

Effects of different iron sources on the performance of LiFePO_4/C composite cathode materials

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Journal of University of Science and Technology Beijing 2008年第6期15卷 802-807页

作者： fei Gao Zhiyuan tang Jianjun Xue School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China Great Power Battery Co. Ltd. Guangzhou 511483 China

Olivine LiFePO4/C composite cathode materials were synthesized by a solid state method in N2 ＋ 5vol% H2 atmosphere. The effects of different iron sources, including Fe（OH）3 and FeC2O4·2H2O, on the performance of as-synthesized cathode materials were investigated and the causes were also analyzed. The crystal structure, the morphology, and the electrochemical performance of the prepared samples were characterized by X-ray diffractometry （XRD）, scanning electron microscopy （SEM）, laser particle-size distribution measurement, and other electrochemical techniques. The results demonstrate that the LiFePO4/C materials obtained from Fe（OH）3 at 800℃ and FeC2O4·2H2O at 700℃ have the similar electrochemical performances. The initial discharge capacities of LiFePO4/C synthesized from Fe（OH）3 and FeC2O4·2H2O are 134.5 mAh.g^-1 and 137.4 mAh.g^-1 at the C/5 rate, respectively. How- ever, the tap density of the LiFePO4/C materials obtained from Fe（OH）3 are higher, which is significant for the improvement of the capacity of the battery.

关键词： iron sources lithium iron phosphate cathode material solid state method

Distributed Deep Learning for Cooperative Computation Offloading in Low Earth Orbit Satellite Networks

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China Communications 2022年第4期19卷 230-243页

作者： Qingqing tang Zesong fei Bin Li School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China School of Computer and Software Nanjing University of Information Science and TechnologyNanjing 210044China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and TelecommunicationsMinistry of EducationNanjing 210003China

Low earth orbit(LEO) satellite network is an important development trend for future mobile communication systems, which can truly realize the“ubiquitous connection” of the whole world. In this paper, we present a cooperative computation offloading in the LEO satellite network with a three-tier computation architecture by leveraging the vertical cooperation among ground users, LEO satellites, and the cloud server, and the horizontal cooperation between LEO satellites. To improve the quality of service for ground users, we optimize the computation offloading decisions to minimize the total execution delay for ground users subject to the limited battery capacity of ground users and the computation capability of each LEO satellite. However, the formulated problem is a large-scale nonlinear integer programming problem as the number of ground users and LEO satellites increases, which is difficult to solve with general optimization algorithms. To address this challenging problem, we propose a distributed deep learning-based cooperative computation offloading(DDLCCO) algorithm, where multiple parallel deep neural networks(DNNs) are adopted to learn the computation offloading strategy dynamically. Simulation results show that the proposed algorithm can achieve near-optimal performance with low computational complexity compared with other computation offloading strategies.

关键词： LEO satellite networks computation offloading deep neural networks

Structural optimization of a settler via CFD simulation in a mixer-settler

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Chinese Journal of Chemical Engineering 2020年第4期28卷 995-1015页

作者： Sishi Ye Qiao tang Yundong Wang Weiyang fei The State Key Laboratory of Chemical Engineering.Department of Chemical Engineering Tsinghua UniversityBeijing 100084China SINOPEC Research Institute of Petroleum Processing Beijing 100083China

This work is aimed at optimizing a settler structure in a *** different aspects have been ***,the flowcharacteristics of a settler have been examined by computational fluid dynamics(CFD)simulation with various agitation speeds of the mixer,as well as organic phase volume fractions ranging from 0.075 to *** aqueous and organic phase turbulent flow fields were measured by particle image velocimetry(PIV)technique to verify the CFD *** organic phases with different physical properties were assessed in the CFD simulation to simulate the liquid-liquid systems related to rare earth element extraction,i.e.,0.072 mol·L^-1 P507/kerosene and 1.8 mol·L^-1 P507/***,the CFD simulation was carried out in a settler equipped with *** effects of number and location of the baffle in the settler on flow features and entrainments of the aqueous and organic outlet were ***,different settler/mixer volume ratios were also *** analyses and comparisons,an optimal design for settler was *** can provide a significant guidance to better mixer-settler design.

关键词： Settler Liquid-liquid CFD RANS equations Optimization

Deep-reinforcement-learning-based UAV autonomous navigation and collision avoidance in unknown environments

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Chinese Journal of Aeronautics 2024年第3期37卷 237-257页

作者： fei WANG Xiaoping ZHU Zhou ZHOU Yang tang School of Astronautics Northwestern Polytechnical UniversityXi’an 710072China School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China

In some military application scenarios,Unmanned Aerial Vehicles(UAVs)need to perform missions with the assistance of on-board cameras when radar is not available and communication is interrupted,which brings challenges for UAV autonomous navigation and collision *** this paper,an improved deep-reinforcement-learning algorithm,Deep Q-Network with a Faster R-CNN model and a Data Deposit Mechanism(FRDDM-DQN),is proposed.A Faster R-CNN model(FR)is introduced and optimized to obtain the ability to extract obstacle information from images,and a new replay memory Data Deposit Mechanism(DDM)is designed to train an agent with a better *** training,a two-part training approach is used to reduce the time spent on training as well as retraining when the scenario *** order to verify the performance of the proposed method,a series of experiments,including training experiments,test experiments,and typical episodes experiments,is conducted in a 3D simulation *** results show that the agent trained by the proposed FRDDM-DQN has the ability to navigate autonomously and avoid collisions,and performs better compared to the FRDQN,FR-DDQN,FR-Dueling DQN,YOLO-based YDDM-DQN,and original FR outputbased FR-ODQN.

关键词： Faster R-CNN model Replay memory Data Deposit Mechanism(DDM) Two-part training approach Image-based Autonomous Navigation and Collision Avoidance(ANCA) Unmanned Aerial Vehicle(UAV)