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Ride-hailing origin-destination demand prediction with spatiotemporal information fusion

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Transportation Safety and Environment 2024年第2期6卷 63-74页

作者： ning Wang liang Zheng Huitao shen Shukai li School of Traffic and Transportation Engineering Central South UniversityChangsha 410075China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China

Accurate demand forecasting for online ride-hailing contributes to balancing traffic supply and demand,and improving the service level of ride-hailing *** contrast to previous studies,which have primarily focused on the inflow or outflow demands of each zone,this study proposes a conditional generative adversarial network with a Wasserstein divergence objective(CWGAN-div)to predict ride-hailing origin-destination(OD)demand *** blocks and refined loss functions help to enhance the stability of model *** conditional information is employed to capture external spatiotemporal dependencies and guide the model towards generating more precise *** analysis using ride-hailing data from Manhattan,New York City,demon-strates that our proposed CWGAN-div model can effectively predict the network-wide OD matrix and exhibits strong convergence *** experiments also show that the CWGAN-div outperforms other benchmarking ***,the proposed model displays potential for network-wide ride-hailing OD demand prediction.

关键词： intelligent transport system ride-hailing generative adversarial networks spatiotemporal dependencies origin-destination(OD)demand prediction

Aparecium:understanding and detecting scam behaviors on Ethereum via biased random Walk

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Cybersecurity 2024年第3期7卷 16-31页

作者： Chuyi Yan Chen Zhang Meng shen ning li Jinhao liu Yinhao Qi zhigang Lu Yuling liu Institute of Information Engineering Chinese Academy of SciencesBeijing 100093China School of Cyber Security University of Chinese Academy of SciencesBeijing 100049China School of Cyberspace Science and Technology Bejing Institute of TechnologyBeijing 100081China

Ethereum's high attention,rich business,certain anonymity,and untraceability have attracted a group of *** on it has become increasingly rampant,among which scam behavior is convenient,cryptic,antagonistic and resulting in large economic *** we consider the scam behavior on Ethereum and investigate it at the node interaction *** on the life cycle and risk identification points we found,we propose an automatic detection model named ***,a graph generation method which focus on the scam life cycle is adopted to mitigate the sparsity of the scam ***,the life cycle patterns are delicate modeled because of the crypticity and antagonism of Ethereum scam *** experiments in the wild Ethereum datasets,we prove Aparecium is effective which the precision,recall and F1-score achieve at 0.977,0.957 and 0.967 respectively.

关键词： Blockchain Network security Ethereum Scam detection Behavior understanding

A study of suspended sediment concentration in Yangshan deep-water port in Shanghai,China

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International Journal of Sediment Research 2012年第1期27卷 50-60页

作者： Shu-hua ZUO ning-chuan ZHANG Bei li shen-liang CheN Key Laboratory of Engineering Sediment of Ministry of Communications Tianjin Research Institute of Water Transport Engineering State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology State Key Laboratory of Estuarine and Coastal Research East China Normal University

Suspended sediment concentration(SSC) plays an important role in the estuarine *** spatial or temporal variations in coastal zones and estuaries indicate that sediments are suspended, transported and deposited under various actions,such as the river discharge,waves,currents and local *** deep-water port is located in the Qiqu Archipelago with many islands and tidal *** Yangshan deep-water port sea area as an example,an analysis of distributions and variations in the SSC based on data measured in Oct.1996,Jan.1999,May 2006 and May 2007 and the surface SSC data measured during the period from 1998 to 2008,has been *** from the study suggest that:(1) the yearly-averaged SSC decreased from 1998 to 2008;(2) the SSC has strong seasonal variations,the monthly-averaged SSC values are higher from November to April of the next year(the winter half year) than from May to October(the summer half year);(3) the periodic nature of the changes are obvious,which is consistent with a tidal semimonthly cycle of approximately 14.8 days;(4) the vertical distribution which is an e exponential distribution increase from the surface to the ***,the data indicate that tidal currents are the most dominant factor affecting the *** the Yangtze River discharges abundant sediments to the study area,it does not directly affect concentration variations in seasonal time *** in yearly variation or long time scales,the SSC varying trend is coincident with sediment discharge change of the Yangtze *** addition,the construction projects,or dumping of sediments,have obvious effects on SSC and sedimentation for part of the area."Strait-channel effects" have some degree of influence to the SSC distribution around islands.

关键词： Yangshan deep-water port Hydrodynamic Suspended sediment concentration(SSC) Strait-channel effects

APPliCATION OF FUZZY LOGIC AND SELF-ORGANIZING NETWORK TO TOOL-WEAR CLASSIFICATION

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Transactions of Nanjing University of Aeronautics and Astronautics 2009年第1期26卷 9-15页

作者：申志刚何宁李亮南京航空航天大学机电学院

A tool-wear monitoring system for metal turning operations is presented based on the combinative application of fuzzy logic and unsupervised neural network. A group of self-organizing map （SOM） neural networks is established based on the typical cutting condition combinations, and each of networks is corresponding to a typical cutting condition. For a specifie cutting condition, the fuzzy logic method is used to select an optimum trained SOM network. The proposed monitoring system, ealled the Fuzzy-SOM-TWC, is used to classify tool states based on the in-time measurement of force, aeoustic emission（AE）, and motor eurrent signals. An approximate 98%--100% correct classification of tool-wear status is obtained by testing the system with a series data samples under freely selected cutting conditions.

关键词： eondition monitoring fuzzy inference self organizing maps

Experimental study of temperature dependence of single-event upset in SRAMs

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Nuclear Science and Techniques 2016年第1期27卷 93-97页

作者： li Cai Gang Guo Jian-Cheng liu Hui Fan Shu-Ting Shi Hui Wang Gui-liang Wang Dong-Jun shen ning Hui An-lin he China Institute of Atomic Energy Beijing 102413China

We report on the temperature dependence of single-event upsets in the 215–353 K range in a 4M commercial SRAM manufactured in a 0.15-lm CMOS process,utilizing thin film transistors. The experimental results show that temperature influences the SEU cross section on the rising portion of the cross-sectional curve(such as the chlorine ion incident). SEU cross section increases 257 %when the temperature increases from 215 to 353 K. One of the possible reasons for this is that it is due to the variation in upset voltage induced by changing temperature.

关键词：温度依赖性单粒子翻转 SRAM 实验截面曲线薄膜晶体管工艺制造 CMOS

light-triggered NO-releasing nanoparticles for treating mice with liver fibrosis

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Nano Research 2020年第8期13卷 2197-2202页

作者： Hongxia liang Zhenhua li zhigang Ren Qiaodi Jia linna Guo Shasha li Hongyu Zhang Shiqi Hu Dashuai Zhu Deliang shen Zujiang Yu Ke Cheng Department of Infectious Disease and hematology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou450052China Department of Molecular Biomedical Sciences and Comparative Medicine Institute North Carolina State UniversityRaleighNC27607USA Joint Department of Biomedical Engineering University of North Carolina at Chapel Hill and North Carolina State UniversityRaleighNC27695USA Department of Cardiology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou450052China The Key Lab of Chemical Biology and Organic Chemistry of henan Province Zhengzhou UniversityZhengzhou450001China

liver fibrosis, resulting from chronic liver damage and characterized by the accumulation of extracellular matrix (ECM) proteins, is a characteristic of most types of chronic liver diseases. The activation of hepatic stellate cells (HSC) is considered an essential pathological hallmark in liver fibrosis. Although nitric oxide (NO) can effectively induce HSC apoptosis, the systemic administration of NO is ineffective and may cause severe complications such as hypotension. To overcome this limitation, nanoparticles were designed to target HSCs and release NO locally under the exposure of near infrared light (NIR). To achieve this, upconversion nanoparticle (UCNP) cores were enveloped in mesoporous silica shells (UCNP@mSiO2), which were modified with hyaluronic acid (HA-UCNP@mSiO2) and Roussin’s black salt (RBS). HA molecules recognize and bind to CD44 proteins, which are overexpressed on activated HSCs. Under exposure to a 980-nm NIR laser, the UCNP cores convert the 980-nm wavelength into ultraviolet (UV) light, which then energizes the RBS (NO donors), resulting in an efficient release of NO inside of the HSCs. Once released, NO triggers HSC apoptosis and reverses the liver fibrosis. This targeted and controlled release method provides the theoretical and experimental basis for novel therapeutic approaches to treat hepatic fibrosis.

关键词： liver fibrosis nitric oxide(NO) hepatic stellate cells(HSC) nanoparticles near infrared light(NIR)-controlled release

Trabecular-like Ti-6Al-4V scaffolds for orthopedic: fabrication by selective laser melting and in vitro biocompatibility

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Journal of Materials Science & Technology 2019年第7期35卷 1284-1297页

作者： Huixin liang Youwen Yang Deqiao Xie Lan li ning Mao Changjiang Wang Zongjun Tian Qing jiang lida shen College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China State Key Laboratory of High Performance Complex Manufacturing Central South UniversityChangsha 410083China Jiangxi University of Science and Technology Ganzhou 341000China Department of Sports Medicine and Adult Reconstructive Surgery Nanjing University Medical School Affiliated Drum Tower HospitalNanjing 210008China Department of Engineering and Design University of SussexSussex HouseBrighton BN19RHUnited Kingdom Suzhou fCangli Orthopedics Instrument Co. Ltd. Suzhou 215624China

Porous metal scaffolds play an important role in the orthopedic field, due to their wide applications in prostheses implantation. Some previous studies showed that the scaffolds with trabecular bone structure reconstructed via computed tomography had satisfactory biocompatibility. However, the reverse modeling scaffolds were inflexible for customized design. Therefore, a top-down designing biomimetic bone scaffold with favorable mechanical performances and cytocompatibility is urgently demanded for orthopedic implants. An emerging additive manufacturing technique, selective laser melting, was employed to fabricate the trabecular-like porous Ti-6Al-4 V scaffolds with varying irregularities(0.05-0.5) and porosities(48.83%–74.28%) designed through a novel Voronoi-Tessellation based method. Micro-computed tomography and scanning electron microscopy were used to characterize the scaffolds’ ***-static compression tests were performed to evaluate the scaffolds’ mechanical properties. The MG63 cells culture in vitro experiments, including adhesion, proliferation, and differentiation, were conducted to study the cytocompatibility of scaffolds. Compressive tests of scaffolds revealed an apparent elastic modulus range of 1.93–5.24 GPa and an ultimate strength ranging within 44.9–237.5 MPa, which were influenced by irregularity and porosity, and improved by heat treatment. Furthermore, the in vitro assay suggested that the original surface of the SLM-fabricated scaffolds was favorable for osteoblasts adhesion and migration because of micro scale pores and ravines. The trabecular-like porous scaffolds with full irregularity and higher porosity exhibited enhanced cells proliferation and osteoblast differentiation at earlier time, due to their preferable combination of small and large pores with various shapes. This study suggested that selective laser melting-derived Ti-6Al-4 V scaffold with the trabecular-like porous structure designed through Voronoi-Tessellation m

关键词： Irregular porous structure Selective laser melting Voronoi-Tessellation Mechanical performance In vitro study

Synthesis of helical Poly(phenylacetylene)s Carrying Dendritic Pendants with Varied Branching Densities Through Polymerization in Different Solvents

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Chinese Journal of Polymer Science 2023年第10期41卷 1543-1554页

作者： Zhen-Zhen Sun Yan-ning Zhang Hao-Yu Qiu Xue-Ting Lu liang-Xuan Ren Le-Fei shen Wen li Afang Zhang International Joint Laboratory of Biomimetic and Smart Polymers School of Materials Science and EngineeringShanghai UniversityShanghai200444China

helical poly(phenylacetylene)s(PPAs)have received extensive attention because of their features in dynamic chirality and promising ***,understanding relationship among the polymer molecular structures,polymerization conditions and tunability of their chirality is of key scientific ***,we developed a novel class of dendronized PPAs carrying 3-fold dendritic oligo(ethylene glycols)(OEGs)via alanine linkage,and found that these bulky polymers exhibited tunable helical conformations through thermally-mediated dehydration and ***,we report on synthesis of a homologous series of dendronized PPAs that carry 2-fold,3-fold or 6-fold dendritic OEG pendants,and focus on effects of molecular topological structures,peripheral units and polymerization solvents on the thermoresponsiveness and their conformation switching *** of branching density and peripheral units(ethoxyl or methoxyl)of the dendritic OEG pendants were examined,and found to play a decisive role on the helical conformation and thermoresponsiveness of these dendronized PPAs due to their different bulkiness and overall *** addition,different polymerization solvents were checked for their possible influence on the polymerization,thermoresponsive behavior and the chirality of the resulting *** polymerization in selective solvents like water or methanol,the obtained dendronized PPAs exhibited weak thermal transitions,while polymerization in non-selective solvent like THF furnished PPAs with characteristic thermoresponsive behavior,indicating that solvents were involved in the process of polymerization of the dendronized *** interestingly,different chiralities of the PPAs through polymerization in various solvents were retained,irrelevant to the purification process and solvents *** work suggests that the topological structures together with polymerization solvents can modulate the thermoresponsive behavior and h

关键词： helical polymer Dendronized polymer Thermores ponsive polymer Solvation Dendritic oligoethylene glycol

Hypoxia-inducible factor-1α induces the epithelial-mesenchymal transition of human prostatecancer cells

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Chinese Medical Journal 2006年第9期119卷 713-718页

作者： LUO Yong he Da-lin ning liang shen Shu-lin li Lei li Xiang Department of Urology First Hospital of Xi＇an Jiaotong University Xi＇an 710061 China

Background Hypoxia-inducible factor- 1α （HIF- 1α） is a transcriptional factor that could improve the stimulation of angiogenesis and the metabolic adaptation of tumor cells to hypoxia. A recent study showed that HIF- 1α could induce colon cancer cells epithelial-mesenchymal transition （EMT）. However, no evidence indicates a similar correlation in human prostate cancer cells. This study was designed to evaluate the effect of HIF- 1α over-expression on the EMT in human prostate cancer cells. Methods We selected the appropriate cell line for HIF- 1α induction from those EMT negative prostate cell lines through vimentin gene detection by RT-PCR. As the result, LNCaP cell line is the best one for further experiment. LNCaP cells were transfected with recombinant plasmid pcDNA3.1 （-）/HIF- 1α and pcDNA3.1 （-） control vector by lipofectamine 2000 system. The positive cell colonies were confirmed by indirect immunofluorescence labeling. Then Transwell polycarbonate filter was used to analyze the invasive potency. The expression of EMT associated proteins, E-cadherin and vimentin, was detected by Western blotting. Results Among four of the EMT negative cell lines, LNCaP was the only one expressed the vimentin gene but not the associated protein. The expression level of HIF- 1α in LNCaP/HIF- 1α was distinctly higher than that in LNCaP/pcDNA3.1 and LNCaP. The cell numbers of LNCaP/HIF- 1α that penetrated through the Transwell filter were higher than that of LNCaP/pcDNA3.1 and LNCaP. Compared with the LNCaP/pcDNA3.1 and LNCaP cells, the expression of vimentin was up-regulated in LNCaP/HIF- 1α, whereas the expression of E-cadherin was down-regulated.Conclusions Over-expression of HIF- 1α stimulates the invasion potency of human prostate carcinoma cells through EMT pathway. The expression of E-cadherin and vimentin, playing established roles in EMT, could be regulated by HIF- 1α in human prostate cancer cell line.

关键词： prostate cancer epithelial-mesenchymal transition hypoxia-inducible factor- 1α