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Groundwater contributions in water-salt balances of the lakes in the badain Jaran Desert,China

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Journal of Arid Land 2016年第5期8卷 694-706页

作者： GONG Yanping WANG Xusheng hu b Xiao ZHOU Yangxiao HAO Chunbo WAN Li MOE Key Laboratory of Groundwater Circulation and Evolution China University of Geosciences Water Engineering Department UNESCO-IHE Institute for Water Education

Groundwater-fed lakes are essential for the ecology in arid and semiarid *** a typical arid region,the badain Jaran Desert （bJD） is famous in the world for the presence of a large number of groundwater-fed saline lakes among the mega *** on the up to date geological surveys and observations,this study analyzed the groundwater contributions in water-salt balances of the lakes in the *** found different types of springs,including the sublacustrine springs that indicate an upward flow of groundwater under the lakebed.A simplified water balance model was developed to analyze the seasonal variations of water level in the Sumu barun Jaran Lake,which revealed an approximately steady groundwater discharge in the lake and explained why the amplitude of seasonal changes in lake level is less than 0.5 *** addition,a salt balance model was developed to evaluate the salt accumulations in the groundwater-fed *** relative salt accumulation time is 800–7,000 years in typical saline lakes,which were estimated from the concentration of Cl-,indicating a long history evolution for the lakes in the *** researches are recommended to provide comprehensive investigations on the interactions between the lakes and groundwater in the bJD.

关键词： arid region groundwater-fed lake spring water level change salinity

An Adaptive Program Recommendation System for Multi-User Sharing Environment

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China Communications 2024年第6期21卷 112-128页

作者： Sun Shiyun hu Zhengying Wei Xin Zhou Liang School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China

More and more accounts or devices are shared by multiple users in video applications,which makes it difficult to provide recommendation *** recommendation schemes overlook multiuser sharing scenarios,and they cannot make effective use of the mixed information generated by multi-user when exploring users’potential *** solve these problems,this paper proposes an adaptive program recommendation system for multi-user sharing ***,we first design an offline periodic identification module by building multi-user features and periodically predicting target user in future sessions,which can separate the profile of target user from mixed log ***,an online recommendation module with adaptive timevarying exploration strategy is constructed by jointly using personal information and multi-user social information provided by identification *** one hand,to learn the dynamic changes in user-interest,a time-varying linear upper confidence bound(LinUCb)based on personal information is *** the other hand,to reduce the risk of exploration,a timeinvariant LinUCb based on separated multi-user social information from one account/device is proposed to compute the quality scores of programs for each user,which is integrated into the time-varying LinUCb by cross-weighting ***,experimental results validate the efficiency of the proposed scheme.

关键词： adaptive exploitation LinUCb multiuser recommendation system

Two New Triterpenoid Saponins from Aster Lingulatus

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Chinese Chemical Letters 1996年第11期7卷 1005-1008页

作者： hu, b Shao, Y Qin, GW Ho, CT Chin, CK Rosen, RT ACAD SINICA SHANGHAI INST MAT MEDSHANGHAI 200031PEOPLES R CHINA RUTGERS STATE UNIV COOK COLLNEW BRUNSWICKNJ 08903

Two new saponins named asterlingulatosides A and b were isolated from the whole plants of Aster lingulatus. Their structures were elucidated by spectral and chemical evidence as 3-O-beta-D-glucopyranosyl-3 beta, 16 alpha-dihydroxyolean-12-en-28-oic acid -28-O-alpha-L-arabinopyranoside and 3-O-beta-D-glucopyranosyl-3 beta,16 alpha-dihydroxyolean-12-en-28-oic acid -28-O-alpha-L-rhamnopyranosyl-(1-->2)- alpha-L-arabinopyranoside respectively. They showed inhibitory activity on DNA synthesis of human leukemia HL-60 cells.

关键词： Lingulatus Two New Triterpenoid Saponins from Aster

Design of a bio-inspired,Two-winged,Flapping-wing Micro Air Vehicle with High-lift Performance

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Journal of bionic Engineering 2024年第3期21卷 1191-1207页

作者： Kai hu huichao Deng Shengjie Xiao Gongyu Yang Yuhong Sun Space Robot Laboratory The School of Mechanical EngineeringBeihang UniversityBeijing100191China

In this paper,we present the development of our latest flapping-wing micro air vehicle(FW-MAV),named Explobird,which features two wings with a wingspan of 195 mm and weighs a mere 25.2 g,enabling it to accomplish vertical take-off and hover *** devised a novel gear-based mechanism for the flapping system to achieve high lift capability and reliability and conducted extensive testing and analysis on the wings to optimise power matching and lift *** Explobird can deliver a peak lift-to-weight ratio of 1.472 and an endurance time of 259 s during hover flight powered by a single-cell LiPo *** the inherent instability of the prototype,we discuss the derivatives of its longitudinal system,underscoring the importance of feedback control,position of the centre of gravity,and increased *** demonstrate the effect of damping enhancement on stability,we also designed a passive stable ***,the vehicle is actively stabilised in roll by adjusting the wing root bars and in pitch through high-authority tail control,whereas yaw is passively *** a series of flight tests,we successfully demonstrate that our prototype can perform vertical take-off and hover flight under wireless *** promising results position the Explobird as a robust vehicle with high lift capability,paving the way towards the use of FW-MAVs for carrying load equipment in multiple tasks.

关键词： Flapping wing biologically inspired robots Mechanical design Flight dynamics Damping enhancement

Unsupervised Multi-Expert Learning Model for Underwater Image Enhancement

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 708-722页

作者： Hongmin Liu Qi Zhang Yufan hu hui Zeng bin Fan the School of Intelligence Science and Technology and the Institute of Artificial Intelligence University of Science and Technology BeijingBeijing 100083China the School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing 100083China IEEE

Underwater image enhancement aims to restore a clean appearance and thus improves the quality of underwater degraded *** methods feed the whole image directly into the model for ***,they ignored that the R,G and b channels of underwater degraded images present varied degrees of degradation,due to the selective absorption for the *** address this issue,we propose an unsupervised multi-expert learning model by considering the enhancement of each color ***,an unsupervised architecture based on generative adversarial network is employed to alleviate the need for paired underwater *** on this,we design a generator,including a multi-expert encoder,a feature fusion module and a feature fusion-guided decoder,to generate the clear underwater ***,a multi-expert discriminator is proposed to verify the authenticity of the R,G and b channels,*** addition,content perceptual loss and edge loss are introduced into the loss function to further improve the content and details of the enhanced *** experiments on public datasets demonstrate that our method achieves more pleasing results in vision *** metrics(PSNR,SSIM,UIQM and UCIQE) evaluated on our enhanced images have been improved obviously.

关键词： Multi-expert learning underwater image enhancement unsupervised learning

Privacy Preserving Algorithm for Spectrum Sensing in Cognitive Vehicle Networks

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Chinese Journal of Electronics 2024年第1期33卷 30-42页

作者： Hongning LI Tonghui hu Jiexiong CHEN Xiuqiang WU Qingqi PEI Guangzhou Institute of Technology Xidian University Guangzhou CEPREI Shaanxi Key Laboratory of blockchain and Secure Computing

The scarcity of spectrum resources fails to meet the increasing throughput demands of vehicular networks. There is an urgent need to maximize the utilization of spectrum bands in mobile networks. To ascertain the availability of spectrum bands, users should engage in wireless channel sensing and collaboration. However, spectrum sensing data always involves users’ privacy, such as their location. This paper first introduces sensing trajectory inference attack in cognitive vehicular networks and then proposes a data confusion-based privacy-preserving algorithm and a cryptonym array-based privacy-preserving aggregation scheme for spectrum sensing in cognitive vehicular networks. Unlike existing methods, the proposed schemes transmit confused data during the aggregation process. This deliberate obfuscation makes it almost impossible to infer users’ location from the transmitted data. The analysis demonstrates the resilience of the proposed schemes against sensing trajectory inference attack.

关键词： Privacy Data privacy Wireless sensor networks Authentication Data aggregation Throughput Inference algorithms

Microstructure and mechanical properties of Ti/Al/Ti clad plates prepared via powder-in-tube method

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Journal of Iron and Steel Research(International) 2024年第3期31卷 670-687页

作者： Xian-lei hu Qin-cheng Xie Yi Yuan Ying Zhi State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina Suzhou Dongbao Haixing Metal Material Technology Co. Ltd.Suzhou 215600JiangsuChina School of Material Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina

The Ti/Al/Ti clad plates exhibit a broad spectrum of potential ***,the conventional techniques of hot-pressing composite and explosive composite are intricate and environmentally hazardous.A novel method was introduced for preparing clad plates,namely,the powder-in-tube *** method involves a combination of cold rolling,annealing at a temperature of 550℃,and double *** morphology of the intermetallic compound layer was analyzed through the utilization of interface stripping test,tensile test,and microscopic *** interface morphology,interface bonding properties,tensile fracture structures,and properties of plates under the first and second rolling were compared,along with the effects of intermetallic compounds on the interface *** results indicate that the powder-in-tube method,when annealed at 550℃,can produce a composite plate featuring a complete and uniform Ti/Al *** obtained plate exhibits a peeling strength of 21.5 N/mm,tensile strength of 424 MPa,and elongation of 11.5%.Furthermore,a systematic analysis was conducted to determine the causes of performance degra-dation observed during annealing at temperatures of 600 and 650℃.

关键词： Powder-in-tube method-Ti/Al/Ti clad plate Annealing Cold rolling-Mechanical property

Aerodynamic optimization of an adaptive flap for next-generation green aircraft

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Chinese Journal of Aeronautics 2024年第2期37卷 100-122页

作者： Tianlong LIN Rosario PECORA Danilo CILIbERTI Wei XIA Shuling hu State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China Deparment of Industrial Engineering Aerospace DivisionUniversity of Naples"FEDERICO II"Napoli 80125Italy

Adaptive,morphing flaps are taking ever-increasing attention in civil aviation thanks to the expected benefits this technology can bring at the aircraft level in terms of high-lift performance improvement and related fuel burnt reduction per *** upon morphing capabilities,it is possible to fix a unique setting for the flap and adapt the flap shape to match the aerodynamic requirements for take-off or *** proper morphed shapes can assure better high-lift performances than those achievable by referring to a conventional ***,standing the unique flap setting for take-off and landing,a dramatic simplification of the flap deployment systems may be *** a consequence of this simplification,the deployment system can be fully hosted in the wing,thus avoiding under-wing nacelles with significantly better aerodynamics and fuel *** first step for a rational design of an adaptive flap consists in defining the target morphed shapes and the unique optimal flap setting in the take-off and landing *** this work,aerodynamic optimization analyses are carried out to determine the best flap setting and related morphed shapes in compliance with the take-off and landing requirements of a reference civil transport *** different initial conditions are adopted to avoid the optimization falling into local optima,thus obtaining four groups of optimal candidate *** comparing each candidate’s performance through 2D and 3D simulations,the optimal configuration has been selected.2D simulations show that the optimal configuration is characterized by a maximum lift increase of 31.92%in take-off and 9.04%in *** to 3D simulations,the rise in maximum lift equals 22.26%in take-off and 3.50%in *** results are finally verified through wind tunnel tests,and the aerodynamic mechanism behind the obtained improvements is explained by carefully analyzing the flow field around the flap.

关键词： Morphing wings High-lift system Adaptive flap Computational Fluid Dynamics(CFD) Wind tunnel tests

Comparison of cytokine levels in prostatic secretion between the Ⅲa and Ⅲb subtypes of prostatitis

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Asian Journal of Andrology 2024年第1期26卷 77-84页

作者： Cheng-Lin Han Yu-Xuan Deng Peng hu bin-Tao hu Tao Wang Ji-Hong Liu Ming-Chao Li Department of Urology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430000China

Chronic prostatitis/chronic pelvic pain syndrome(CP/CPPS),also known as National Institutes of Health(NIH)type Ⅲ prostatitis,is a common disorder with an unclear etiology and no known curative *** on the presence or absence of leukocytes in expressed prostatic secretion(EPS),CP/CPPS is classifiedfurther into Illa(inflammatory)and Illb(noninflammatory)***,the severity of symptoms is not entirely consistent with the white blood cell(WbC)*** the preliminary finding of a link between inflammatory cytokines and CP/CPPS,we performed this clinical study with the aim of identifying cytokines that are differentially expressed according to whether the prostatitis subtype is Ⅲa or Ⅲ*** found that granulocyte colony-stimulating factor(G-CSF),interleukin-18(IL-18),and monocyte chemoattractant protein-1(MCP-1)levels were significantly elevated and interferon-inducible protein-10(IP-10)and platelet-derived growth factor-bb(PDGF-bb)levels were downregulated in the EPS of patients with type Ⅲa *** a word,it is a meaningful study in which we investigate the levels of various cytokines in EPS according to whether prostatitis is the Ⅲa or Ⅲb *** combination of G-CSF,IL-18,MCP-1,IP-10,and PDGF-bb expression levels could form a basis for classification,diagnosis,and therapeutic targets in clinical P/CPPS.

关键词： chronic prostatitis/chronic pelvic pain syndrome(CP/CPPS) cytokines NIH-Ⅲa NIH-Ⅲb