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Cloaking Region Based Passenger Privacy Protection in Ride-Hailing Systems

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Journal of Computer Science & Technology 2020年第3期35卷 629-646页

作者： Yubin Duan Guo-ju Gao Ming-jun Xiao Jie wu Department of Computer and Information Sciences Temple UniversityPennsylvania 19122U.S.A. School of Computer Science and Technology University of Science and Technology of ChinaHefei 230036China

With the quick development of the sharing economy,ride-hailing services have been increasingly popular *** the service provides convenience for users,one concern from the public is whether the location privacy of passengers would be *** providers(SPs)such as Didi and Uber need to acquire passenger and driver locations before they could successfully dispatch passenger *** protect passengers’privacy based on their requirements,we propose a cloaking region based order dispatch *** our scheme,a passenger sends the SP a cloaking region in which his/her actual location is not *** trade-off of the enhanced privacy is the loss of social welfare,i.e.,the increase in the overall pick-up *** optimize our scheme,we propose to maximize the social welfare under passengers’privacy *** investigate a bipartite matching based approach.A theoretical bound on the matching performance under specific privacy requirements is *** passengers’privacy,we allow drivers to set up their maximum pick-up distance in our extended *** extended scheme could be applied when the number of drivers exceeds the number of ***,the global matching based scheme does not consider the interest of each individual *** passengers with low privacy requirements may be matched with drivers far from *** this end,a pricing scheme including three strategies is proposed to make up for the individual loss by allocating discounts on their riding *** experiments on both real-world and synthetic datasets show the efficiency of our scheme.

关键词： order dispatch pricing privacy ride-hailing

Microfluidic Channel Fabrication Process Utilizing Nd:YVO4 Laser-Melting Technique

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Chinese Physics Letters 2017年第4期34卷 39-42页

作者： ju-Nan Kuo Jian-Liang wu Department of Automation engineering National Formosa University Yunlin 632

A simple and repeatable method is proposed for fabricating microfluidic channels on polydimethylsiloxane （PDMS） substrates. In the proposed approach, ridge structures with the required microchannel dimensions are formed on the surface of a borosilicate glass substrate by means of a laser-induced melting process. The patterned substrate is then used as a mold to transfer the microchannel structures to a PDMS layer. Finally, the PDMS layer is aligned with a glass cover plate and is sealed using an oxygen plasma treatment process. The proposed patterning technique is a maskless method, and is thus cheaper and more straightforward than conventional lithography techniques. Moreover, unlike direct laser ablation methods, the proposed method requires significantly less input energy, and therefore minimizes thermal effects such as substrate cracking and distortion. The feasibility of the proposed fabrication method is demonstrated by measuring the capillary filling speed of human blood plasma in microfluidic channels with cross-section sizes of 19.5 × 2.5, 17.0 × 1.6, and 7.6 × 1.1 μm^2 （widthxheight）, respectively, and temperatures of 4℃, 25℃ and 37℃. It is shown that the filling speed reduces with a reducing channel cross-section size, a lower operating temperature, and an increased filling length.

关键词： Microfluidic Channel Fabrication Process Utilizing Nd:YVO4 Laser-Melting Technique Nd

Tunable strain effect on the charge/orbital ordering state in electron-doped La0.9Hf0.1MnO3 films

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Science China(Physics,Mechanics & Astronomy) 2013年第3期56卷 535-539页

作者： WANG Lin GUO erJia wu ZhenPing GAO ju Department of Physics The University of Hong Kong Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of Sciences Institute for Metallic Materials IFW DresdenHelmholtzs traβe 20Dresden 01069Germany

The impact of the lattice strain on the charge/orbital ordering state was studied by using a heterostructure composed with electron-doped La 0.9 Hf 0.1 MnO 3(LHMO) and ferro-and piezoelectric 0.67Pb(Mg1/3Nb2/3)*** ferroelectric poling induces a significant reduction in the biaxial tensile strain in the LHMO film,leading to a decrease in the film resistance over the whole temperature range and an increase in the insulator to metal transition temperature T *** resistance of LHMO film exhibits different responses to the external electric fields and lattice deformation,which is attributed to the coactions of converse piezoelectric effect and ferroelectric polarity *** modification of charge/orbital ordering phase by the electric fields and ferroelectric polarization suggests that the unstable states in the manganites are sensitive to strain effects.

关键词： electron-doped manganite strain effects

Hot deformation behavior and microstructure evolution of Be/2024Al composites

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International Journal of Minerals,Metallurgy and Materials 2023年第11期30卷 2245-2258页

作者： Yixiao Xia Zeyang Kuang Ping Zhu Boyu ju Guoqin Chen Ping wu Wenshu Yang Gaohui wu School of Materials Science and engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Advanced Structure-Function Integrated Materials and Green Manufacturing Technology School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China Key Laboratory of Advanced Science and Technology on High Power Microwave Xi'an 710024China Northwest Institute of Nuclear Technology Xi'an 710024China

The high temperature compression test of Be/2024Al composites with 62wt%Be was conducted at 500–575℃ and strain rate of0.003–0.1 s^(-1).The strain-compensated Arrhenius model and modified Johnson–Cook model were introduced to predict the hot deformation behavior of Be/2024Al *** result shows that the activation energy of Be/2024Al composites was 363.364 k J·mol^(-1).Compared with composites reinforced with traditional ceramics,Be/2024Al composites can be deformed with ultra-high content of reinforcement,attributing to the deformable property of Be *** average relative error of the two models shows that modified Johnson–Cook model was more suitable for low temperature condition while strain-compensated Arrhenius model was more suitable for high temperature *** processing map was generated and a hot extrusion experiment was conducted according to the map.A comparation of the microstructure of Be/2024Al composites before and after extrusion shows that the Be particle deformed coordinately with the matrix and elongated at the extrusion direction.

关键词： Be/Al composites hot deformation behavior constitutive model hot extrusion

Fetal and neonatal programming of postnatal growth and feed efficiency in swine

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Journal of Animal Science and Biotechnology 2017年第4期8卷 764-778页

作者： Yun Ji Zhenlong wu Zhaolai Dai Xiaolong Wang ju Li Binggen Wang Guoyao wu State Key Laboratory of Animal Nutrition China Agricultural UniversityBeijing 100193 China Henan Yinfa Animal Husbandry Co. Ltd. XinzhengHenan 451100 China Department of Animal Science and Center for Animal Genomics Texas A&M University Room 212 College Station TX 77843 USA.

Maternal undernutrition or overnutrition during pregnancy alters organ structure, impairs prenatal and neonatal growth and development, and reduces feed efficiency for lean tissue gains in pigs. These adverse effects may be carried over to the next generation or beyond. This phenomenon of the transgenerational impacts is known as fetal programming, which is mediated by stable and heritable alterations of gene expression through covalent modifications of DNA and histones without changes in DNA sequences(namely, epigenetics). The mechanisms responsible for the epigenetic regulation of protein expression and functions include chromatin remodeling; DNA methylation(occurring at the 5′-position of cytosine residues within CpG dinucleotides); and histone modifications(acetylation, methylation, phosphorylation, and ubiquitination). Like maternal malnutrition, undernutrition during the neonatal period also reduces growth performance and feed efficiency(weight gain:feed intake; also known as weightgain efficiency) in postweaning pigs by 5–10%, thereby increasing the days necessary to reach the market bodyweight. Supplementing functional amino acids(e.g., arginine and glutamine) and vitamins(e.g., folate) play a key role in activating the mammalian target of rapamycin signaling and regulating the provision of methyl donors for DNA and protein methylation. Therefore, these nutrients are beneficial for the dietary treatment of metabolic disorders in offspring with intrauterine growth restriction or neonatal malnutrition. The mechanism-based strategies hold great promise for the improvement of the efficiency of pork production and the sustainability of the global swine industry.

关键词： epigenetics Fetal programming Gene expression Neonatal programming Nutrition

Synthesis and Optical Properties of ZnO Nanoparticles in Submicron PS Hollow Reactors

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Chinese Journal of Chemical Physics 2012年第6期25卷 719-724,I0004页

作者： Xue-feng Huang Fei-fei ju Mo-zhen Wang Xue-wu Ge CAS Key Laboratory of Soft Matter Chemisry Department of Polymer Science and EngineeringUniversity of Science and Technology of China Hefei 230026 China

ZnO nanoparticles were first encapsulated in submicron PS hollow microspheres through two-step swelling process of core-shell structured PMMA/PS （PMMA： polymethyl methao- rylate） microspheres in acid-alkali solution, and the ZnO precursors, i.e. the ethanol solu- tions of （CHaCOO）2Zn and LiOH. The transmission electron microscope, X-ray diffraction, and thermogravimetric analysis results show that the feeding order of ethanol solutions of （CH3COO）2Zn and LiOH in the second swelling step has great influence on the loading efficiency and the size of ZnO nanoparticles, but little on their crystal form. The photolumi- nescence and UV-Vis absorption behavior of ZnO/PS microspheres show that the PS shell can effectively avoid the fluorescence quenching effect.

关键词： ZnO/PS hybrid material Core-shell polymer Swelling PS hollow microsphere Optical property

Ultrafast optical modulation of the fluorescence from a single-photon emitter in silicon carbide

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Photonics Research 2024年第5期12卷 941-946页

作者： MeNGTING He YUJING CAO juNJIe LIN ZHIPING ju BOTAO wu e wu State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200241China Photon Technology(Zhejiang)Co. Ltd.Jiaxing 314100China National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200000China Department of Physics and Shanghai Key Laboratory for Magnetic Resonance East China Normal UniversityShanghai 200241China Chongqing Key Laboratory of Precision Optics Chongqing Institute of East China Normal UniversityChongqing 401120China Collaborative Innovation Center of extreme Optics Shanxi UniversityTaiyuan 030006China

The quest for the room-temperature optical transistor based on nonlinearities in single atoms or molecules is attracting a lot of *** this work,a single-photon emitter in cubic silicon carbide is verified that can operate as an optical switch at room temperature under pulsed green laser illumination with a near-infrared pulsed laser as the control *** demonstrated an ultrafast and reversible optical modulation with a high photoluminescence intensity suppression ratio up to 97.9%and a response time as short as 287.9±5.7 *** current development provides insights for high-precision and ultrafast optical switches,with possibilities for integration with emerging electronic installations to realize more intelligent photoelectric integrated devices.

关键词： emitter carbide photon

Geochemistry of the Mesoproterozoic Intrusions, Geochronology and Isotopic Constraints on the Xiaonanshan Cu-Ni Deposit along the Northern Margin of the North China Craton

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Journal of earth Science 2020年第4期31卷 653-667页

作者： Zhiguang Zhou Jiangwei Yi Niu Guosheng Wang Chen wu Changfeng Liu juncheng ju School of earth Sciences and Resources China University of GeosciencesBeijing 100083China Institute of Geological Surveyy China University of Geosciences Beijing 100083China Minmetals exploration&Development Co. Ltd.Beijing 100010China Tianjin Institute of Geological Survey Tianjin 300191China exploration and Development Research Institute of Petro China Liaohe Oilfield CompanyPanjin 124000China

Mesoproterozoic magma events in the Bayan Obo rift belt have remained poorly constrained and as a result, the Late Paleoproterozoic–Mesoproterozoic tectonic evolution of the rift belt has remained unclear. By a multiple-facetted regional geological investigation of this belt, we have resolved the stratigraphic sequence and geochronology of the Bayan Obo Group and made new discoveries including a three-stage mantle-derived magmatic sequence. Zircon and baddeleyite dating of Xiaonanshan hornblende pyroxenite emplaced into the Bayan Obo Group yields 207Pb/206Pb ages of ca. 1.34 and 1.33 Ga. The geochronological, geochemistry, Hf isotopic analyses place an important constraint on ages of the Late Paleoproterozoic–Mesoproterozoic strata and the evolution of the rift belt. Our field observations and U-Pb dating results suggest that mineralization is genetically related to Mesoproterozoic magmatism in North China Craton, i.e., 1.33–1.34 Ga. The δ34SV-CDT values of sulphide from the ore-bearing ultra-/mafic samples are about 6.2‰, whereas the 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb values vary in the ranges of 17.598–18.115, 15.496–15.501, and 37.478–37.952, respectively. The Late Paleozoic mafic gabbro and acidic granite porphyry intrusions are possible to bimodal magmatic event related to the extensional tectonic setting of the Central Asia in this period.

关键词： Bayan Obo rift belt North China Craton Late Paleoproterozoic-Mesoproterozoic tectonic evolution Mesoproterozoic mineralization Pb-S isotopic analysis

A global synthesis of the effectiveness and ecological impacts of management interventions for Spartina species

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Frontiers of environmental Science & engineering 2023年第11期17卷 263-272页

作者： Shengyu Wang Philip A.Martin Yan Hao William J.Sutherland Gorm e.Shackelford Jihua wu Ruiting ju Wenneng Zhou Bo Li Ministry of education Key Laboratory for Biodiversity Science and ecological engineering National Observations and Research Station of Wetland Ecosystems of the Yangtze EstuaryInstitute of Biodiversity Science and Institute of Eco-ChongmingSchool of Life SciencesFudan UniversityShanghai 200438China Biosecurity Research Initiative at St Catharine’s(BioRISC) St Catharine’s CollegeUniversity of CambridgeCambridgeCB21RLUK Conservation Science Group Department of ZoologyUniversity of CambridgeCambridgeCB23QZUK State Key Laboratory of Grassland Agro-ecosystems and College of ecology Lanzhou UniversityLanzhou 730000China Guangdong Provincial Key Laboratory of Water Quality Improvement and ecological Restoration for Watersheds School of EcologyEnvironment and ResourcesGuangdong University of TechnologyGuangzhou 510006China Ministry of education Key Laboratory for Transboundary ecosecurity of Southwest China Yunnan Key Laboratory of Plant Reproductive AdaptationEvolutionary Ecology and Centre for Invasion BiologyInstitute of BiodiversitySchool of Ecology and Environmental ScienceYunnan UniversityKunming 650504China

Invasions by Spartina species pose serious threats to global coastal *** many studies have examined the effectiveness and ecological impacts of invasive Spartina management,no comprehensive global synthesis has been conducted to assess the effects of management on Spartina per se and on wider ***,we conducted a global meta-analysis of 3,459 observations from 102 studies to quantify the effects of different management interventions(physical,chemical,biological,and integrated control)on Spartina per se and native biodiversity and *** found that physical measures quickly suppressed Spartina but that their effectiveness declined over *** contrast,chemical measures decreased the abundance and growth of Spartina to a lesser degree in the early stage,but the effectiveness increased over *** management measures did not significantly decrease the diversity of native biota on the whole,but native-plant diversity significantly decreased with time after physical *** management measures did not affect abiotic factors *** results support the use of chemical measures to control invasive Spartina,although their effectiveness would depend on the time since the management *** the problem of Spartina regrowth following physical control requires improved *** hold that initial states of invaders and subsequent environmental changes after management interventions should be weighed in evaluating control efficacy.

关键词： Plant invasion Biodiversity Meta-analysis Restoration Salt marshes Treatment timing