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Eventual Leader Election with weak Assumptions on Initial knowledge,Communication Reliability,and Synchrony

Journal of Computer Science & Technology 2010年第6期25卷 1267-1281页

作者： Antonio Fernndez Anta Ernesto jimnez Michel Raynal Institute IMDEA Networks Avenida del Mar Mediterraneo EUI Universidad Politcnica de Madrid IRISA Universit de Rennes

This paper considers the eventual leader election problem in asynchronous message-passing systems where an arbitrary number t of processes can crash（t〈n,where n is the total number of processes）.It considers weak assumptions both on the initial knowledge of the processes and on the network *** precisely,initially,a process knows only its identity and the fact that the process identities are different and totally ordered（it knows neither n nor t）.Two eventual leader election protocols and a lower bound are *** first protocol assumes that a process also knows a lower bound α on the number of processes that do not *** protocol requires the following behavioral properties from the underlying network：the graph made up of the correct processes and fair lossy links is strongly connected,and there is a correct process connected to（n〈f）-α other correct processes（where f is the actual number of crashes in the considered run） through eventually timely paths（paths made up of correct processes and eventually timely links）.This protocol is not communication-efficient in the sense that each correct process has to send messages *** second protocol is communication-efficient：after some time,only the final common leader has to send messages *** protocol does not require the processes to know α,but requires stronger properties from the underlying network：each pair of correct processes has to be connected by fair lossy links（one in each direction）,and there is a correct process whose n〈f-1 output links to the rest of correct processes have to be eventually timely.A matching lower bound result shows that any eventual leader election protocol must have runs with this number of eventually timely links,even if all processes know all the processes *** addition to being communication-efficient,the second protocol has another noteworthy efficiency property,namely,be the run finite or infinite,all the local variables and message fields have

关键词： eventually timely and fair lossy links eventual leader election failure detector omega leader oracle process initial knowledge

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A new method for deriving broad-band polar motion geodetic excitations

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Geodesy and Geodynamics 2024年第5期15卷 453-464页

作者： wei Chen Jiesi Luo jim Ray Jiancheng Li Hubei Luojia Laboratory School of Geodesy and GeomaticsWuhan UniversityWuhan 430079China National Oceanic and Atmospheric Administration Silver SpringMDUSA Central South University Changsha 410083China

while the geodetic excitationχ(t)of polar motion p(t)is essential to improve our understanding of global mass redistributions and relative motions with respect to the terrestrial frame,the widely adopted method to deriveχ(t)from p(t)has biases in both amplitude and phase *** study has developed a new simple but more accurate method based on the combination of the frequency-and time-domain Liouville's equation(FTLE).The FTLE method has been validated not only with 6-h sampled synthetic excitation series but also with daily and 6-h sampled polar motion measurements as well asχ(t)produced by the interactive webpage tool of the International Earth Rotation and Reference Systems Service(IERS).Numerical comparisons demonstrate thatχ(t)derived from the FTLE method has superior performances in both the time and frequency domains with respect to that obtained from the widely adopted method or the IERS webpage tool,provided that the input p(t)series has a length around or more than 25 years,which presents no practical limitations since the necessary polar motion data are readily *** FTLE code is provided in the form of Mat Lab function.

关键词： Earth rotation Polar motion Geodetic excitation Liouville's equation Mat Lab

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Unraveling the electrocatalytically active sites and stability of Co&Co oxides on nanocarbon for oxygen evolution reaction in acid solution

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Journal of Energy Chemistry 2020年第10期29卷 8-13页

作者： Yansong Zhu Tianran Zhang Tao An Yun Zong jim Yang Lee Faculty of Pharmacy Shenyang Pharmaceutical UniversityShenyang 110016LiaoningChina Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore Institute of Materials Research and Engineering(IMRE) Singapore

The oxygen evolution reaction(OER)in acid solution is a significant challenge for non-precious metal electrocatalysts based on the transition metals although they have shown good OER performance in alkaline *** this study,we synthesized the electrocatalysts containing two or three Co species(Co,CoO and Co3O4)nanoparticles on porous graphitic carbon(PGC)nanosheets which were prepared by a facile and low-cost synthesis where Co(NO3)2•6H2O and glucose were pyrolyzed in the presence of sodium chloride *** Co3O4-dominated catalyst as-prepared,Co3O4/PGC,is OER active in acid solution(1.74 V at a current density of 10 mA cm^−2).we identified the OER active sites in the catalyst to be the Co3O4 nanoparticles rather than carbon-coated *** comparative studies of the varied catalysts,we also proved that Co3O4 is catalytically more active than Co and *** Co3O4/PGC catalyst,however,lost almost of all its activity after 100 voltammetric cycles in the 1.2-1.8 V voltage *** the catalyst stability was examined potentiostatically at different potentials,the catalyst showed good stability at 1.4 *** stability study also revealed the mechanism of the catalyst instability in acid was caused by Co3O4 reduction below 1.4 V and by Co3O4 oxidation above 1.4 V.1.4 V is therefore a unique potential where Co3O4 nanoparticles are neither oxidized nor reduced to be susceptible to acid dissolution.

关键词： Non-precious metal Active sites Oxygen evolution reaction Acid Stability

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Natural sediment at a dam and its inorganic materials as adsorbents of praseodymium(Pr(Ⅲ))

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International Journal of Sediment Research 2023年第4期38卷 566-575页

作者： Melania jiménez-Reyes Jaime jiménez-Becerril Marcos Solache-Ríos Perla Tatiana Almazán-Sánchez Departamento de Química Instituto Nacional de Investigaciones Nucleares Carretera México-Toluca S/N CONACy T-Instituto Nacional de Investigaciones Nucleares

The sediment deposited behind a dam(DS) and its inorganic materials(IM-DS) were characterized and used for the removal of praseodymium(Pr) from aqueous solutions. Quartz, albite, and kaolinite were found in the sediment by X-ray diffraction. kinetic data fit well to a pseudo second-order model, the equilibrium time for DS and IM-DS was 2 h and 3 min, respectively, and the adsorption capacity was higher for Pr/DS(qe= 4.91 mg/g) than for Pr/IM-DS(qe= 3.01 mg/g) in these conditions. Pr/DS and Pr/IM-DS data isotherms were in agreement with the Langmuir-Freundlich model and the maximum adsorption capacities were 4.95 and 4.01 mg/g, respectively. Both processes are exothermic(enthalpy change, ΔH0=-22.8 and-21.8 k J/mol for DS and IM-DS, respectively), the increase of the randomness is small, and the feasibility and spontaneity are low. Praseodymium was desorbed by ethylenediaminetetraacetic acid disodium(EDTA-Na2), sodium chloride, nitric, citric, and humic acids solutions, and one hundred percent of praseodymium was desorbed by the EDTA-Na2solution. The Pr2(EDTA)3(praseodymium ethylenediaminetetraacetate) complex was completely desorbed from both materials(DS and IM-DS). Distribution coefficients(kD) depend upon praseodymium concentration,temperature, p H, and the kind of adsorbent. Chemical reactions of praseodymium with kaolinite and iron minerals could explain the adsorption.

关键词： Praseodymium Sediment Adsorption process parameters Desorption

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Evolution and challenges of DNS-based GDMs

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Digital Communications and Networks 2018年第4期4卷 235-243页

作者： Zheng wang jim Huang Scott Rose Advanced Network Technologies Division^National Institute of Standards and Technology USA School of Computer Science Chongqing University of Posts and TelecommunicationsChina

DNS-based server redirecting is considered the most popular means of deploying CDNs. However, with the inaeasing use of i"emol:e DNS, DNS-based CDNs face a great challenge in performance degradation. To address this issue, encouraging progress has been made in both industry and research communities. In this article,state-of- art solutions for the remote DNS problem are discussed at first. Next, privacy concerns about DNS-based CDNs, including client location as well as redirection privacy, are identified and a representative solution is summarized. Finally, the solution is compared to those in prior works under different measures, and a discussion on DNS-based CDN applications is provided. A model is also established to deepen the underst;anding of CDN performance. we believe that this survey will shed light on the application of DNS-based CDNs, and it is expected to provide design guidelines to CDN service providers.

关键词： Index terms Content delivery network DNS-Based server redirecting Remote DNS DNS privacy

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Land Parcel Land Use History as a key to Site Selectionfor Documenting Soil Contamination Risk: a Case Study from Australian Suburbia

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Geo-Spatial Information Science 2005年第4期8卷 257-261,275页

作者： YU Jie Ursula Pietrzak jim Peterson School of Remote Sensing and Information Engineering Wuhan University 129 Luoyu Road Wuhan 430079 China 不详

In that orcharding in early to mid twentieth century southeastern Australia involved use of certain heavy metal and As compounds in regular pest control spray procedures, some interest attaches to the possibility that these landparcels are underlain by soils with above background Cu, Pb and As levels. Interpretation of Land cover changes allowed land parcels previously occupied by orchards to be identified in the 1950s through time series air photos. A comparison of soil analysis results referring to soil samples from control sites, and from land parcels formerly occupied by orchardists, shows that contamination (above background) levels of cations in the pesticides can be found in the top 6 cm of former orchard soils. It is clear that digital spatial data handling and culturally informed air photo interpretation has a place in soil contamination studies, land use planning (with particular reference to re development) and in administration of public health.

关键词： aerial photography digital orthophoto image soil contamination soil analysis land-use planning public health

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Sex differences in Alzheimer's disease:an urgent research venue to follow

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Neural Regeneration Research 2024年第12期19卷 2569-2570页

作者： Raquel jiménez-Herrera Ana Contreras Juan D.Navarro-López Lydia jiménez-Díaz Neurophysiology&Behavior Lab University of Castilla-La ManchaSchool of Medicine of Ciudad RealCiudad RealSpain

Due to increasing life expectancy,the amount of people with dementia worldwide is expected to experience a substantial rise,with estimates indicating a growth from 55 million in 2019 to a staggering 139 million by the... 详细信息

关键词： Alzheimer predominant estimates

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Geochemical Indication of Sinian Bedded Siliceous Rocks in the Hunan-Guizhou-Guangxi Area and Their Environmental Significance

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Acta Geologica Sinica(English Edition) 2000年第1期74卷 46-53页

作者： PENG jim YI Haisheng XIA wenjie Postdoctoral Researchers Flow Station of Sw China Petroleum Institute Institute of Sedimentary Geology Chengdu University of Technology Chengdu 610059 Institute of Sedimentary Geology Chengdu University of Technology Chengdu 610059

: In the Hunan-Guizhou-Guangxi area there have developed very thick bedded siliceous rocks of the late Sinian. The rocks have a fairly pure composition, with an average content of siliceous minerals exceeding 95%. They are relatively rich in Fe and Mn, and poor in Al, Ti and Mg. The Fe/Ti, (Fe+Mn)/Ti, Al/(Al+Fe+Mn) and U/Th ratios and the Al-Fe-Mn and Fe-Mn-(Ni+Co+Cu)×10 triangle diagrams all show that they are hydrothermal sedimentary siliceous rocks. In the rocks the total amount of REEs is low, the δCe shows an obvious negative anomaly and the δEu a weak anomaly, and LREE>HREE, all indicating that they are products of hydrothermal processes. The δ30Si and δ18O values, as well as the formation temperature of the rocks all clearly show that the silica forming the rocks comes from hot water. Besides, analyses of the depositional environment of the rocks using the MnO/TiO2 ratio and the δCe and δ30Si values yield the same conclusion that they are formed in environments from continental marginal slopes of a bathyal environment to oceanic basins of a deep-sea environment.

关键词： siliceous rock hydrothermal sedimentary geochemistry environment Sinian the Hunan-Guizhou-Guangxi area

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Processing of Aerosol Particles in Convective Cumulus Clouds:Cases Study in the Mexican East Pacific

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Advances in Atmospheric Sciences 2010年第6期27卷 1331-1343页

作者： José C.jimNEZ-ESCALONA Oscar PERALTA ESIME UP Ticomán National Polytechnic Institute Chemistry Faculty National Autonomous University of MexicoCiudad Universitaria

In the Mexican Intertropical Convergence Zone, particle size distributions within 500 m of cloud boundaries at altitudes of 1000, 2500, and 4200 m, were compared against size distributions at the same levels but 1500 m away from the clouds. The differences in the distributions near and far from the cloud are related to processes that may change particle properties inside the cloud. Chemical changes in the aerosols are deduced from the particles＇ refractive index, as derived from comparisons with the scattering coeflcient measured by a nephelometer. An analysis of ten cloud systems indicates that vertical transport of cloud base aerosol followed by entrainment/detrainment is the cloud processing signature most frequently observed in the comparisons （65%）. Changes in the chemical composition are observed in approximately 20% of the cases and another 20% of the cases showed removal by precipitation. About 5% of the comparisons showed clear evidence of changes by coalescence. The principal effect of these cloud-processed aerosols is observed in the increase of optical depth in the layer from 30 m to 4200 m in the near-cloud regions, in comparison with the atmosphere further from clouds.

关键词： cloud processing cloud interaction scattering redistribution entrainment

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Gene therapy: light is finally in the tunnel

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Protein & Cell 2011年第12期2卷 973-989页

作者： Huibi Cao Robert S.Molday jim Hu Programme in Physiology and Experimental Medicine Hospital for Sick ChildrenDepartments of Laboratory Medicine and Pathobiologyand PaediatricsUniversity of TorontoTorontoOntario M5G1X8Canada Department of Biochemistry and Molecular Biology 2350 Health Sciences MallUniversity of British ColumbiaVancouverB.C.V6T 1Z3Canada

After two decades of ups and downs,gene therapy has recently achieved a milestone in treating patients with Leber’s congenital amaurosis(LCA).LCA is a group of inherited blinding diseases with retinal degeneration and severe vision loss in early *** in several genes,including RPE65,cause the *** adenoassociated virus as a vector,three independent teams of investigators have recently shown that RPE65 can be delivered to retinal pigment epithelial cells of LCA patients by subretinal injections resulting in clinical benefits without side ***,considering the whole field of gene therapy,there are still major obstacles to clinical applications for other *** obstacles include innate and immune barriers to vector delivery,toxicity of vectors and the lack of sustained therapeutic gene ***,new strategies are needed to overcome these hurdles for achieving safe and effective gene *** this article,we shall review the major advancements over the past two decades and,using lung gene therapy as an example,discuss the current obstacles and possible solutions to provide a roadmap for future gene therapy research.

关键词： gene therapy transgenes viral vector non-viral vector helper-dependent adenoviral vector adenoassociated virus lentivirus cystic fibrosis transmembrane conductance regulator(CFTR) host immune responses

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