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捷克斯洛伐克制造的CME3t型内燃机车

国外内燃机车 1987年第11期 1-6页

作者： Ivan ra’dl 顾永麟

捷克斯洛伐克的布拉格CkD机车厂完成了对CME3M型内燃机车的改进,其两台样车曾在捷克斯洛伐克和苏联经受了运行试验。这些内燃机车的运行试验,首先是证实了电阻制动在减少制动闸瓦更换量从而降低运用费用方面表现的突出的优点以及电子控... 详细信息

捷克斯洛伐克的布拉格CkD机车厂完成了对CME3M型内燃机车的改进,其两台样车曾在捷克斯洛伐克和苏联经受了运行试验。这些内燃机车的运行试验,首先是证实了电阻制动在减少制动闸瓦更换量从而降低运用费用方面表现的突出的优点以及电子控制在优化控制过程和降低运用中燃油消耗量方面的优越性。该型内燃机车除了采用电阻制动以外,还具有其他一些现代化的特点,诸如柴油机冷却系统采用预热,电阻制动控制中采用电子技术等。两台样车是于1984年制成的。根据对基础性试验结果所作的评价,使人们有可能对其作一些必要的改进,并于1985年1月交付苏联作牵引运行。第一批20台这种内燃机车的交贷是在1985年年底前完成的。另一批50台这种改进型内燃机车是于1986年年底交货的。

关键词：内燃机车电气设备运行试验机电设备试运行可靠性试验 CME3t 电阻制动柴油机冷却系统捷克斯洛伐克

An Expert System Oriented towards the Detection of Influenza and Dengue Developed on Mobile Platforms

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Journal of Software Engineering and Applications 2015年第6期8卷 295-301页

作者： raúl Beltrán ramírez Rocío Maciel Arellano Carlos González Sandoval Adauto Casas Flores Departamento de Sistemas de Información Universidad de Guadalajara Periférico NorteZapopanMéxico Centro de Ensenanza técnica Industrial GuadalajaraMéxico

Nowadays, mobile technology makes it possible for us to realize processes in a relatively short amount of time, showing the user friendly and efficient interfaces that any person is capable of adapting to. Continuing this trend, we develop a mobile application that aids in giving an early diagnosis of Influenza and Dengue, two diseases that affect approximately 5% of the world population (in the case of Dengue) and 5% - 15% of the northern hemisphere (in the case of influenza). Our application consists of an expert system based on fuzzy logic that analyzes symptoms introduced by the user and formulates a diagnosis in approximately 2 - 4 minutes. this system considerably reduced the diagnostic time, improving the recuperation process from these diseases due to their early detection.

关键词： Mobile technology Mobile Applications Dengue Influenza Expert System

the Impact of Social Media Networks Websites Usage on Students’ Academic Performance

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Communications and Network 2015年第4期7卷 159-171页

作者： Mahmoud Maqableh Lama rajab Walaa Quteshat ra’ed Moh’d taisir Masa’deh tahani khatib Huda karajeh Management Information Systems Faculty of Business The University of Jordan Amman Jordan Computer Information Systems King Abdullah II School for Information Technology University of Jordan Amman Jordan

Social Networks Sites (SNSs) are dominating all internet users’ generations, especially the students’ communities. Consequently, academic institutions are increasingly using SNSs which leads to emerge a crucial question regarding the impact of SNSs on students’ academic performance. this research investigates how and to what degree the use of SNSs affects the students’ academic performance. the current research’s data was conducted by using drop and collect surveys on a large population from the University of Jordan. 366 undergraduate students answered the survey from different faculties at the university. In order to study the impact of SNSs on student’s academic performance, the research hypotheses was tested by using descriptive analysis, t-test and ANOVA. Research results showed that there was a significant impact of SNS on the student’s academic performance. Also, there was a significant impact of SNS use per week on the student’s academic performance, whereas no differences found in the impact of use of SNSs on academic performance due to age, academic achievement, and use per day to most used sites. the findings of this research can be used to suggest future strategies in enhancing student’s awareness in efficient time management and better multitasking that can lead to improving study activities and academic achievements.

关键词： Social Network Sites Academic Performance University Students t-test ANOVA

Words apart:Standardizing forestry terms and definitions across European biodiversity studies

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森林生态系统:英文版 2023年第4期10卷 459-471页

作者： Giovanni trentanovi thomas Campagnaro tommaso Sitzia Francesco Chianucci Giorgio Vacchiano Christian Ammer MichałCiach thomas ANagel Miren del Río Yoan Paillet Silvana Munzi kris Vandekerkhove Andrés Bravo-Oviedo Andrea Cutini Ettore D'Andrea Pallieter De Smedt Inken Doerfler Dimitris Fotakis Jacob Heilmann-clausen Jeňýk Hofmeister Jan Hošek Philippe Janssen Sebastian kepfer-Rojas Nathalie korboulewsky Bence kovács Daniel kozák thibault Lachat Anders Mårell radim Matula Martin Mikoláš Björn Nordén PéterÓdor x Marko Perović Elisabeth Pötzelsberger Peter Schall Miroslav Svoboda Flóra tinya Mariana Ujházyová Sabina Burrascano Research Institute on terrestrial Ecosystems-National Research Council(IREt-CNR) Via Madonna Del Piano 1950019Sesto FiorentinoFIItaly Department of Land EnvironmentAgriculture and ForestryUniversitàdegli Studi di PadovaViale Dell’Università1635020LegnaroPDItaly National Biodiversity Future Center Piazza Marina 6190133PalermoItaly CREA Research Centre for Forestry and Wood Viale S.Margherita 8052100ArezzoItaly Department of Agricultural and Environmental Sciences(DISAA) University of MilanVia Celoria 220133MilanItaly Silviculture and Forest Ecology of the temperate Zones University of GöttingenGermany Department of Forest Biodiversity Faculty of ForestryUniversity of Agricultureal.29 Listopada 4631-425KrakówPoland Department of Forestry and Renewable Forest Resources Biotechnical FacultyUniversity of LjubljanaVecna pot 831000LjubljanaSlovenia Instituto de Ciencias Forestales(ICIFOR-INIA) CSICCtra.de la Coruña Km 7.528040MadridSpain University Grenoble Alpes LessemINRAE2 Rue de la Papeterie38402 Saint-Martin-d'HèresFrance Centro Interuniversitário de História Das Ciências e da tecnologia Faculdade de CiênciasUniversidade de LisboaPortugal Centre for Ecology Evolution and Environmental ChangesFaculdade de Ciências&CHANGE-Global Change and Sustainability InstituteUniversidade de LisboaPortugal Research Institute for Nature and Forest(INBO) Havenlaan 88 Bus 731000BrusselBelgium Department of Biogeography and Global Change National Museum of Natural Sciences-CSICC/Serrano 115bis28006MadridSpain Research Institute on terrestrial Ecosystems-National Research Council(IREt-CNR) Via G.Marconi N.205010PoranoTRItaly Forest&Nature Lab Department of EnvironmentGhent UniversityGeraardsbergsesteenweg 2679090GontrodeBelgium Institute of Biology and Environmental Science Vegetation Science&Nature ConservationUniversity of OldenburgAmmerländer Heerstraße 114-11826129OldenburgGermany Forest Research Institute Hellenic Agricultural Organization DimitraVassilikaThessal

Forest biodiversity studies conducted across Europe use a multitude of forestry terms,often *** hinders the comparability across studies and makes the assessment of the impacts of forest management on biodiversity highly *** attempts to standardize forestry and stand description terminology mostly used a top-down approach that did not account for the perspectives and approaches of forest biodiversity *** work aims to establish common standards for silvicultural and vegetation definitions,creating a shared conceptual framework for a consistent study on the effects of forest management on *** have identified both strengths and weaknesses of the silvicultural and vegetation information provided in forest biodiversity *** quantitative data on forest biomass and dominant tree species are frequently included,information on silvicultural activities and vegetation composition is often lacking,shallow,or based on broad and heterogeneous *** discuss the existing classifications and their use in European forest biodiversity studies through a novel bottom-up and top-driven review process,and ultimately propose a common *** will enhance the comparability of forest biodiversity studies in Europe,and puts the basis for effective implementation and monitoring of sustainable forest management *** standards here proposed are potentially adaptable and applicable to other geographical areas and could be extended to other forest interventions.

关键词： Forest management Multi-taxon terminology Silviculture Data harmonization

Experimental Evaluating of the Physical, Mechanical and Durability Properties of Natural, Recycled and Both Combined Aggregates Based Concretes

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Materials Sciences and Applications 2023年第3期14卷 117-141页

作者： Etienne Malbila Arba A.t. Ouedraogo Nicolas kagambega Gilbert G. Nana Sié kam David Y. k. toguyeni Ecole Supérieure d’Ingénierie (ESI) Université de Fada N’Gourma (UFDG) Fada-N’Gourma Burkina Faso Laboratoire d’Energies thermiques Renouvelables (LEtRE) Université Joseph KI ZERBO Ouagadougou Burkina Faso Laboratoire de Géosciences et Environnement (LaGE) Université Joseph KI ZERBO Ouagadougou Burkina Faso Laboratoire de Physique et Chimie de l’Environnement (LPCE) Université Joseph KI ZERBO Ouagadougou Burkina Faso Ecole Polytechnique de Ouagadougou (EPO) Ouagadougou Burkina Faso

this experimental study aims at the reuse of recycled aggregates (ra), resulting from the demolition of concrete, cement block and cement mortar, in the manufacture of common construction in Burkina Faso. the ra can readily replace natural aggregates in concrete. then five formulations of natural and recycled aggregates based concrete for characteristic strength of 25 Mpa were prepared in addition to the natural aggregates base concrete named reference concrete (BN): two types of recycled aggregates concrete (BR), three types of recycles and natural combined aggregates base concrete (BC). the properties of natural and recycled aggregates were characterized and the physical, mechanical strength and durability properties were also evaluated for all concrete specimens. All the studied concrete formulation present a density between 2000 kg/m3 ≤ ρ ≥ 2600 kg/m3 and an average slump of 4.9 ± 0.1 cm. the obtained results indicate that the recycled aggregates are suitable for current concrete. two out of the five combinations studied, such as the natural (BN) and combined aggregate (BC2) based concretes satisfy the mechanical characteristics (Rc28 > 25 MPa) at 28 days of age and an average absorption coefficient of 2.93% and 3.98%. the recycled aggregate based concrete (BR1, BR2) and combined aggregate based concrete (BC1), gave respective average compressive strength of 21.55 MPa, 20.50 MPa and 20.30 MPa, i.e. a difference of 13.80% to 18.80% under the characteristic strength (25 MPa) aimed at 28 days of age. thus, the recycled aggregates are in conformity with the normative prescriptions and their use for standard concrete gives adequate physical, mechanical and durability properties for the production of the C20/25 concrete series in the common civil engineering applications.

关键词： Concrete Demolition Waste Aggregate Recycled Aggregate Strength Water Absorption

Magnetic relaxation behavior of a spatially closed dysprosium(Ⅲ) phthalocyaninato double-decker complex

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Science China Chemistry 2012年第6期55卷 918-925,1178-1184页

作者： kAtOH keiichi UMEtSU kaori BREEDLOVE BRIAN k. YAMASHItA Masahiro Department of Chemistry Graduate School of Science Tohoku University 6-3 Aramaki-Aza-Aoba Aoba-ku Sendai Miyagi 980-8578 Japan

the SMM properties of the spatially closed dy（Ⅲ） double-decker Pc complex dy（obPc）2 （1）, which is equivalent to a pseudo dinuclear complex, are reported. Complex 1 crystallized with ethanol in the crystal lattice in the monoclinic space group P22/n and was isomorphous with tb（obPc）2 （3）, which is arranged in a dimer structure along the b axis. the intermetallic dy-dy distance was determined to be 0.756 nm. ZMt versus t plots for 1 decreased with a decrease in t, which suggests the existence of an antiferromagnetic （AF） interaction between the dy3＋ ions. the M-H curve for 1 at 1.8 k showed magnetic hysteresis. In ac susceptibility measurements on a powder sample of 1, which were dependent on the applied ac field, indicating that 1 is an single molecule magnet （SMM）, a maximum appeared at 22 k at an ac frequency 09 of 1488 Hz. the shape of the peaks dras- tically changed, and the peaks did not shift when an Hd~ large enough to suppress the quantum tunneling of the magnetization （QtM） was applied. the energy barrier （A/hc） was estimated to be 44 cm-1 with a pre-exponential factor （r0） of 1.6 × 10-5 s from an Arrhenius plot. Our results suggest that the SMM/magnetic properties of 1 significantly change in a dc magnetic field. these relaxation mechanisms are related to the energy gap of the ground state and to QtM.

关键词： single-molecule magnets dysprosium double-decker complex pseudo dinuclear complex magnetic relaxation process

He and Ar isotopes in mantle megacryst minerals from Nushan and Yingfengling in Southeast China

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Chinese Science Bulletin 2003年第15期48卷 1624-1630页

作者： XUShijin FANGZhong t.Matsumoto J.Matsuda M.Yasuda YUJinhai WANGRucheng LIUWenzhong DepartmentofEarthSciences StateKeyLaboratoryforMineralDepositsResearchNanjingUniversityNanjing210093China DepartmentofEarthandSpaceSciences OsakaUniversityOsaka560-0043Japan

He and Ar isotopic compositions of megacrystal minerals from mantle xenoliths were measured by the technique of vacuum crushing extraction. the used samples were clinopyroxene, garnet and ilmenite in Cenozoic alkaline basalts, which were from Nushan in Anhui Province and Yingfengling in Guangdong Province, respectively, and represented materials from the upper mantle in the continental margin of SE China. the results show 3He/4He ratios of 7.99 ra to 8.58 ra, consistent with the characteristic ratios of the MORB-type mantle. 40Ar/39Ar ratios vary from 313 to 909, suggesting a binary mixing between the MORB-type mantle and air argons. this may reflect the incorporation of the air argon absorbed in oceanic sediments into the mantle beneath the continental margin by subduction of oceanic plate. this study presents the first report that ilmenite megacrysts contain abundant fluid inclusions and noble gases in the mantle xenoliths.

关键词：东南地区中国氦氩亏损地幔

Statistical data driven approach of COVID-19 in Ecuador: R_(0) and R_(t) estimation via new method

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Infectious Disease Modelling 2021年第1期6卷 232-243页

作者： raúl Patricio Fernandez-Naranjo MSc Eduardo Vasconez-Gonzalez MD katherine Simbana-RiveraMD,MSc Lenin Gomez-Barreno MD Juan S.Izquierdo-Condoy MD Domenica Cevallos-RobalinoMD,MPH(c) Esteban Ortiz-Prado MD,MSc,MPH One Health Research Group Faculty of MedicineUniversidad de las AmericasQuitoEcuador Resident of Intensive Care Unit Hospital Quito Sur IESSQuitoEcuador

the growth of COVID-19 pandemic throughout more than 213 countries around the world have put a lot of pressures on governments and health services to try to stop the rapid expansion of the *** 2009,H1N1 Influenza pandemic,statistical and mathematical methods were used to track how the virus spreads around *** of these models that were developed at the beginning of the XXI century are based on the classical susceptible-infected-recovered(SIR)model developed almost a hundred years *** evolution of this model allows us to forecast and compute basic and effective reproduction numbers(R_(t) and R_(0)),measures that quantify the epidemic potential of a pathogen and estimates different *** this study,we present a traditional estimation technique for R_(0) with statistical distributions by best fitting and a Bayesian approach based on continuous feed of prior distributions to obtain posterior distributions and computing real time R_(t).We use data from COVID-19 officially reported cases in Ecuador since the first confirmed case on February *** of the lack of data,in the case of R_(0) we compare two methods for the estimation of these parameters below exponential growth and maximum likelihood *** do not make any assumption about the evolution of cases due to limited information and we use previous methods to compare scenarios about R_(0) and in the case of R_(t) we used Bayesian inference to model uncertainty in contagious proposing a new modification to the well-known model of Bettencourt and Ribeiro based on a time window of m days to improve *** R_(0) with exponential growth criteria was 3.45 and with the maximum likelihood estimation method was *** results show that Guayas,Pichincha and Manabíwere the provinces with the highest number of cases due to *** reasons explain the increased transmissibility in these localities:massive events,population density,cities dispersion patterns,and

关键词： Bayesian inference R0 COVID-19 Real time reproduction factor Basic reproduction factor Ecuador

HoD Detector, a System to Create Indicators about the Happiness of Citizens in a Smart City: Case of Study—GDL Smart City

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Journal of Software Engineering and Applications 2016年第10期9卷 524-532页

作者： raúl Beltrán ramírez Rocío Maciel Arellano Leopoldo Gómez Víctor Larios Rosillo Carlos González Sandoval Departamento de Sistemas de Información Universidad de Guadalajara Periférico Norte Zapopan México Centro de Ense&ntilde anza técnica Industrial Guadalajara México

Happiness is the ultimate goal for every living human being, and this condition motivates people to stay active and want to be alive. Having this feeling also fosters the proactivity of citizens. the opposite is depression, a condition capable of significantly affecting a person’s behavior or perception. HoD Detector is a low-cost, easy to use application that aids in the diagnosis of a depressive disorder and motivates the user to seek professional help. the purpose of this study is to propose a way to measure happiness through the measurement of depression;to develop HoD Detector, evaluate the accuracy and usability of this application (with university students) for future enhancements of the system. the development of this application involved basic algorithms and the use of a database to successfully make a diagnosis and store the results of each user for further reference. the application is capable of giving a proper diagnosis with the time interval of 2 - 5 minutes. HoD Detector has the potential to become an extremely useful tool to diagnose depression and motivate users to seek professional help not only in Mexico, but also on an international scale for improving in people’s happiness condition.

关键词： Smart Cities Smart City Metrics Mental Health Happiness Depression mHealth App