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Navigation for UAV Pair-Supported Relaying in Unknown IoT Systems with Deep Reinforcement Learning

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Chinese Journal of Electronics 2022年第3期31卷 416-429页

作者： HUANG Fei li Guangxia WANG Haichao TIAN Shiwei yang yang CHANG Jinghui The College of Communications Engineering Army Engineering University of PLA The National Innovation Institute of Defense Technology Chinese Academy of Military Sciences The Satellite Communication Center

Unmanned aerial vehicles(UAVs) have recently been regarded as a promising technology in Internet of things(IoT). UAVs functioned as intermediate relay nodes are capable of establishing uninterrupted and high-quality communication links between remotely deployed IoT devices and the destination. Multiple UAVs are required to be deployed due to their limited onboard energy. We study a UAV pair-supported relaying in unknown IoT systems, which consists of transmitter and receiver. Our goal is that transmitter gathers the data from each device then transfers the information to receiver,and receiver finally transmits the information to the destination, while meeting the constraint that the amount of information received from each device reaches a certain threshold. This is an optimization problem with highly coupled variables, such as trajectories of transmitter and receiver. On account of no prior knowledge of the environment, a dueling double deep Q network(dueling DDQN) algorithm is proposed to solve the *** it is in the phase of transmitter’s receiving information or the phase of transmitter’s forwarding information to receiver, the effectiveness and superiority of the proposed algorithm is demonstrated by extensive simulationsin in comparison to some base schemes under different scenarios.

关键词： deep reinforcement learning unmanned aerial vehicles deep learning (artificial intelligence) reinforcement learning transmitter UAV pair-supported relaying autonomous aerial vehicles high-quality communication links unknown IoT systems remotely deployed IoT devices aircraft navigation dueling DDQN algorithm Internet of Things intermediate relay nodes dueling double deep Q network algorithm

EXPERIMENTAL INVESTIGATION OF CHARACTERISTIC FREQUENCY IN UNSTEADY HYDRAUliC BEHAVIOUR OF A LARGE HYDRAUliC TURBINE

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Journal of Hydrodynamics 2009年第1期21卷 12-19页

作者： WANG Fu-jun li Xiao-qin MA Jia-mei yang Min ZHU yu-liang College of Water Conservancy and Civil Engineering China Agricultural University Beijing 100083 China Beijing Huake Tongan Monitoring Technology Co. Ltd. Beijing 100037 China

The features of unsteady flow such as pressure variation and fluctuation in a large hydraulic turbine usually lead to the instability of operation. This article reports the recent in site investigation concerning the characteristic frequencies in pressure fluctuation, shaft torsional oscillation and structural vibration of a prototype 700 MW Francis turbine unit. The investigation was carried out for a wide load range of 200 MW-700 MW in the condition of water head 57 m-90 m. An extensive analysis of both time-history and frequency data of these unsteady hydraulic behaviours was conducted. It was observed that the pressure fluctuation in a draft tube is stronger than that in upstream flow passage. The low frequency with about one third of rotation frequency is dominative for the pressure fluctuation in part load range. Also the unsteady features of vibration of head cover and torsional oscillation of shaft exhibited the similar features. Numerical analysis showed that the vibration and oscillation are caused by vortex rope in the draft tube. In addition, a strong vibration with special characteristic frequency was observed for the head cover in middle load range. The pressure fluctuation in the draft tube with the same frequency was also recorded. Because this special vibration has appeared in the designed normal running condition, it should be avoided by carefully allocating power load in the future operation.

关键词： hydraulic turbine part load swirling flow unsteady behaviour characteristic frequency power load allocation

Malaria control along China-Myanmar Border during 2007–2013: an integrated impact evaluation

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Infectious Diseases of Poverty 2016年第1期5卷 680-690页

作者： Jian-Wei Xu Yong li Heng-lin yang Jun Zhang Zai-Xing Zhang Ya-Ming yang Hong-Ning Zhou Joshua Havumaki Hua-Xian li Hui liu Hua Zhou Xin-yu Xie Jia-Xiang Dong yue Zhang Xiao-Ying Sun Bo li Jia-Yin li yang-Hui Tian Pi-yu Wang Ben-Fu li yunnan Institute of Parasitic Diseases Yunnan Provincial Center of Malaria ResearchYunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and ControlYunnan Provincial Key Laboratory of Vector-borne Diseases Control and ResearchPuer 665000China yunnan Provincial Health and Family Planning Commission Kunming 650200People’s Republic of China yunnan Office of Health Poverty Action Kunming 650041People’s Republic of China World Health Organization Regional Office for the Western Pacific P.O.Box 29321000 ManilaPhilippines Foundation for Innovative New Diagnostics 1216 CointrinGenevaSwitzerland

Background:Implementing effective interventions remain a lot of difficulties along all border *** emergence of artemisinin resistance of Plasmodium falciparum strains in the Greater Mekong Subregion is a matter of great *** has effectively controlled cross-border transmission of malaria and artemisinin resistance of *** along the China-Myanmar ***:A combined quantitative and qualitative study was used to collect data,and then an integrated impact evaluation was conducted to malaria control along the China-Myanmar border during ***:The parasite prevalence rate(PPR)in the five special regions of Myanmar was decreased from 13.6%in March 2008 to 1.5%in November *** with the baseline(PPR in March 2008),the risk ratio was only 0.11[95%confidence interval(CI),0.09-0.14]in November 2013,which is equal to an 89%reduction in the malaria *** parasite incidence(API)across 19 Chinese border counties was reduced from 19.6 per 10000 person-years in 2006 to 0.9 per 10000 person-years in *** with the baseline(API in 2006),the API rate ratio was only 0.05(95%CI,0.04-0.05)in 2013,which equates to a reduction of the malaria burden by 95.0%.Meanwhile,the health service system was strengthened and health inequity of marginalized populations reduced along the international ***:The effective collaboration between China,Myanmar and the international non-governmental organization promptly carried out the core interventions through simplified *** integrated approaches dramatically decreased malaria burden of Chinese-Myanmar border.

关键词： Border malaria Control Artemisinin resistance China-Myanmar border

S19W,T27W,and N33OY mutations in ACE2 enhance SARS-CoV-2 S-RBD binding toward both wild-type and antibody-resistant viruses and its molecular basis

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Signal Transduction and Targeted Therapy 2021年第10期6卷 3096-3107页

作者： Fei Ye Xi lin Zimin Che Fanli yang Sheng lin Jing yang Hua Chen Honglu Sun lingling Wang Ao Wen Xindan Zhang yushan Dai yu Cao Jingyun yang Guobo Shen li yang Jiong li Zhenling Wang Wei Wang Xiawei Wei Guangwen Lu West China Hospital Emergency Department(WCHED) State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengduSichuanChina Disaster Medicine Center West China HospitalSichuan UniversityChengduSichuanChina Laboratory of Aging Research and Cancer Drug Target State Key Laboratory of Biotherapy and Cancer CenterNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengduSichuanChina

SARS-CoV-2 recognizes,via its spike receptor-binding domain(S-RBD),human angiotensin-converting enzyme 2(ACE2)to initiate ***-domain protein of ACE2 can therefore function as a *** we show that mutations of S19W,T27W,and N330Y in ACE2 could individually enhance SARS-CoV-2 S-RBD binding.Y330 could be synergistically combined with either W19 or W27,whereas W19 and W27 are mutually *** structures of SARS-CoV-2S-RBD bound to the ACE2 mutants reveal that the enhan ced binding is mainly con tributed by the van der Waals interactio ns mediated by the aromatic side-chai ns from W19,W27,and *** Y330 and W19/W27 are distantly located and devoid of any steric interference,W19 and W27 are shown to orient their side-chains toward each other and to cause steric conflicts,explai ning their in ***,using pseudotyped SARS-CoV-2 viruses,we dem on strate that these residue substitutions are associated with dramatically improved entry-inhibition efficacy toward both wild-type and antibody-resistant *** together,our biochemical and structural data have delineated the basis for the elevated S-RBD binding associated with S19W,T27W,and N330Y mutations in ACE2,paving the way for potential application of these mutants in dinical treatment of COVID-19.

关键词： ACE2 elevated RBD

Research progresses of nanomaterials as lubricant additives

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Friction 2024年第7期12卷 1347-1391页

作者： Zhengquan JIANG Yankun SUN Bokang liU Laigui yu yuping TONG Mingming YAN Zhongzheng yang Yongxing HAO linjian SHANGGUAN Shengmao ZHANG Weihua li School of Materials Science and Engineering North China University of Water Resources and Electric PowerZhengzhou 450045China Institute of Special Friction and Lubricating Materials North China University of Water Resources and Electric PowerZhengzhou 450045China Nanomaterials Engineering Research Center Henan UniversityKaifeng 475001China School of Mechanical Engineering North China University of Water Resources and Electric PowerZhengzhou 450045China

Friction and wear are unavoidable in mechanical *** use of lubricants with nano-additives can effectively reduce friction and wear,which is of great significance to saving energy and protecting the *** present,great progress has been made in the scientific research and industrial application of nano-additives for *** paper mainly introduces the types of nano-additives for lubricants(such as carbon nanomaterials,nano-metals,nano-oxides,sulfides,complexes,polymers,etc.),the tribological properties of lubricants with different components of nano-additives,and the lubrication mechanisms of the nano-additives(including tribofilm formation,rolling ball bearing effect,repairing effect,polishing effect,and synergistic effect).It also deals with the dispersion of nano-additives in lubricants and the influences of their particle size and microstructure on the tribological properties of *** review outlines the performance requirements of nano-additives in different lubrication states,discusses the use of nano-additives in challenging working conditions,and identifies various industrial oil nano-additives with reference to the appropriate options in diverse working ***,the existing problems of nano-additives and their application prospects are *** review,hopefully,would help to shed light on the design and synthesis of novel high-performance nano-additives and promote their application in engineering.

关键词： nanomaterials lubricant additive lubrication mechanism research progress

Embryo-Engineered Nonhuman Primate Models:Progress and Gap to Translational Medicine

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Research 2021年第1期2021卷 1627-1639页

作者： Mei Huang Jiao yang Peng li Yongchang Chen yunnan Key Laboratory of Primate Biomedical Research Institute of Primate Translational MedicineKunming University of Science and TechnologyKunming 650500China State Key Laboratory of Primate Biomedical Research Kunming 650500China

Animal models of human diseases are vital in better understanding the mechanism of pathogenesis and essential for evaluating and validating potential therapeutic *** close relatives of humans,nonhuman primates(NHPs)play an increasingly indispensable role in advancing translational medicine *** this review,we summarized the progress of NHP models generated by embryo engineering,analyzed their unique advantages in mimicking clinical patients,and discussed the remaining gap between basic research of NHP models to translational medicine.

关键词： diseases Medicine translational

Construction of MoS2 field effect transistor sensor array for the detection of bladder cancer biomarkers

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Science China Chemistry 2020年第7期63卷 997-1003页

作者： yujie yang Bo Zeng Yingxue li Huageng liang Yanbing yang Quan yuan Key Laboratory of Analytical Chemistry fo r Biology and Medicine(Ministry of Education) College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China Institute of Chemical Biology and Nanomedicine State Key Laboratory of Chemo/Biosensing and ChemometricsCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Department of Urology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Key Laboratory fo r Micro-fNano-Optoelectronic Devices of Ministry of Education School of Physics and ElectronicsHunan UniversityChangsha 410082China

Bladder cancer is one of the commonest malignant tumors of urinary system with high recurrence. However, currently developed bladder cancer urine diagnosis methods are hindered by the low detection sensitivity and accuracy. Herein, a molybdenum disulfide(MoS2) nanosheets-based field effect transistor(FET) sensor array was constructed for simultaneous detection of multiple bladder cancer biomarkers in human urine. With the excellent electronic property of MoS2 and the high specific identification capability of recognition molecules, the proposed biosensor array could simultaneously detect nuclear matrix protein 22(NMP22) and cytokeratin 8(CK8) with a wide linear range of 10-6–10-1 pg mL-1 and an ultra-low detection limit of 0.027 and 0.019 aM, respectively. Furthermore, this highly sensitive and specific MoS2 FET sensor array could be used to identify bladder cancer biomarkers from human urine samples. This designed high-performance biosensor array shows great potential in the future diagnosis of bladder cancer.

关键词： MoS 2 field effect transistor bladder cancer sensor array NMP22 CK8

A Quantitative Study of Fault Zone Sealing

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Acta Geologica Sinica(English Edition) 2010年第1期84卷 185-193页

作者： li yang ZHAO Mifu Department of Exploration and Development SINOPEC Beijing 100029 China Dongxin Production Factory Shengli Oilfield Branch Company SINOPEC Dongying 207068 China

A fault is not simply a plane, but a zone consisting of a series of broken planes or lower faults. The greater the scale of faults, the wider and more complex the fault zone is. Fault-sealing properties are influenced by the fault zone itself, whose fault displacement, depth, net-to-gross-ratio of mudstone, fault plane angle, and fault mechanical properties play important controlling roles. The sealing of hydrocarbon by the fault zone depends on whether the fault zone can form a continuous sealing zone and if the pore throats connecting those fault zones are small enough. The concept of fault zone-sealing potential is proposed here, and a quantitative formula is established by using a great amount of practical statistical data as well as the fuzzy comprehensive evaluation method, which is a comprehensive characterization parameter to judge whether or not fault zones could seal oil hydrocarbon. The greater the value of the fault zone-sealing potential, the better sealed the fault is. For example, with increasing depth, the sealing degree of the Xin 68 Fault in the Dongxin 1 oilfield changes greatly, reflecting the complexity of fault-sealing properties.

关键词： fault fault-sealing properties fault zone-sealing potential Xin 68 Fault

Construction of multiwavelets with high approximation order and symmetry

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Science China Mathematics 2009年第8期52卷 1607-1616页

作者： yang ShouZhi li YouFa Department of Mathematics Shantou UniversityShantou 515063China

In this paper, based on existing symmetric multiwavelets, we give an explicit algorithm for constructing multiwavelets with high approximation order and symmetry. Concretely, suppose Φ(x):= (φ1(x), ..., φr(x)) T is a symmetric refinable function vectors with approximation order m. For an arbitrary nonnegative integer n, a new symmetric refinable function vector Φnew(x):= (φ 1 new (x), ..., φ r new (x)) T with approximation order m + n can be constructed through the algorithm mentioned above. Additionally, we reveal the relation between Φ(x) and Φnew(x). To embody our results, we construct a symmetric refinable function vector with approximation order 6 from Hermite cubics which provides approximation order 4.

关键词： refinable function vectors multiwavelets approximation order symmetry 42C15 94A12