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利用质疑改进教育信息技术标准化活动：更多关注其范围和原理(英文)

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华东师范大学学报（自然科学版） 2012年第2期 25-34,41页

作者： t.hoel J.MASON 奥斯陆和阿克什胡斯应用技术学院教育研发中心奥斯陆0130挪威昆士兰科技大学教育学院昆士兰4001澳大利亚

标准化对于开发"学习、教育和培训"(LEt)中使用的"信息通信技术"(ICt)有重要意义,但ICt的利益相关者(stakeholders)却往往质疑标准化活动.本文提出,利用这种质疑形式来分析和改进当前的ICt标准化活动.讨论了由各方参与产生ICt标准过程... 详细信息

标准化对于开发"学习、教育和培训"(LEt)中使用的"信息通信技术"(ICt)有重要意义,但ICt的利益相关者(stakeholders)却往往质疑标准化活动.本文提出,利用这种质疑形式来分析和改进当前的ICt标准化活动.讨论了由各方参与产生ICt标准过程的模型框架,其中一系列"为什么"的问题(Why questions)起着重要作用.讨论主要围绕两个方面:一是标准及相关事物在发展过程中的管理与核准;二是如何识别LEt中的相关问题与可用来解决这些问题的创新技术.给出了两个事例:一个是对"内容共享对象参考模型"(Sharable Content Object Refer-ence Model,SCORM)的质疑,这能帮助理解该模型;特别是对其适用范围(scope)的质疑而使该模型更完善.另一个是对制定"新工作条款"(New Work Items)必要性的质疑,使人们认识到澄清标准中有关技术原理(rationale)的重要性.

关键词：标准管理 ICt标准数字化学习信息系统架构企业框架 ItLEt(学习、教育和培训中的信息技术)

transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 177-192页

作者： M.NAVEED M.IMRAN t.ASGHAR Z.ABBAS Department of Mathematics Division of Science and TechnologyUniversity of Education Department of Mathematics The Islamia University of Bahawalpur

this paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. the influence of magnetic fields is also inspected in terms of their physical characteristics. to depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAM).the effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

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Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-tALOOKOLAEI H.GHANDVAR E.JUMAEV S.KHAtIR t.CUONG-LE School of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and Science Center for Engineering Application and technology Solutions Ho Chi Minh City Open University

this paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. the strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. the curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. Subsequently, the natural frequencies and transient response of the system are determined. the accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

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应用分子生物学研究资料进行危险度评定

卫生毒理学杂志 1988年第2期 127-128页

作者： David hoel 美国国家环境健康科学研究所生物测试流行病学及危险度评定部主任

近年来美国国家环境健康科学研究所(NIEHS)生物测试流行病学及危险度评定部(DBERA)在致癌危险度评定(Car-cinogenicity Risk Assessment)研究中取得下列一些进展: Ⅰ.探讨小鼠自发肿瘤的性质应用小鼠进行致癌试验较多,为此必须考察小鼠

关键词：小鼠肝脏生物测试平方根流行病学化学物二次方根自发肿瘤消化系肿瘤肝脏肿瘤毒性作用危险系数危险度二次方

Leveraging ROtI map derived from Indonesian GNSS receiver network for advancing study of Equatorial Plasma Bubble in Southeast/East Asia

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Earth and Planetary Physics 2025年第1期9卷 101-116页

作者： Prayitno Abadi Ihsan N.Muafiry teguh N.Pratama Angga Y.Putra Suraina Gatot H.Pramono Sidik t.Wibowo Febrylian F.Chabibi Umar A.Ahmad Wildan P.tresna Asnawi Research Center for Climate and Atmosphere Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia School of Electrical Engineering Telkom UniversityBandungIndonesia Directorate of Laboratory Management Facilities and Science and technology Park Indonesian National Research and Innovation Agency(BRIN)PontianakIndonesia Geophysics Laboratory Master Program in PhysicsUniversitas Gadjah Mada(UGM)YogyakartaIndonesia Research Center for Space Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia Indonesian Geospatial Information Agency(BIG) JakartaIndonesia Research Center for Photonics Indonesian National Research and Innovation Agency(BRIN)Tangerang SelatanIndonesia Department of Earth and Planetary Sciences Hokkaido UniversitySapporoJapan

this paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signals and degrade positioning *** by the Indonesian Geospatial Information Agency(BIG),the Indonesia Continuously Operating Reference Station(Ina-CORS)network comprises over 300 GNSS receivers spanning equatorial to southern low-latitude ***-CORS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast *** provide a practical tool for EPB research,by sharing two-dimensional rate of total Electron Content(tEC)change index(ROtI)derived from this *** generate ROtI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific *** preliminary findings from the ROtI maps of Ina-CORS are ***,the Ina-CORS ROtI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther ***,we demonstrate that combined ROtI maps from Ina-CORS and GNSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East *** have demonstrated the combined ROtI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on May 11,*** observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities *** sharing ROtI maps from Indonesia and integrating them with regional GNSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionosphe

关键词： Equatorial Plasma Bubble(EPB) GNSS receivers’network Indonesia Continuously Operating Reference Station(Ina-CORS) ionospheric map Rate of tEC change index(ROtI)map

MICROStRUCtURES AND MECHANICAL PROPERtIES OF IN-SItU Al_2O_3/tiAl COMPOSItES BY EXOtHERMIC DISPERSION MEtHOD

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Acta Metallurgica Sinica(English Letters) 2008年第6期21卷 437-443页

作者： t.t. Ai Department of Materials Science and Engineering Shaanxi University of Technology Hanzhong 723003 China

In-situ Al2O3/tiAl composites were fabricated by pressure-assisted exothermic dispersion （PAXD） method from elemental powder mixtures of ti, Al, tiO2, and Nb2O5. the microstructures and mechanical properties of the as-sintered composites are investigated. the results show that the as-sintered products consist of γ-tiAl, α2-ti3Al, Al2O3, and NbAl3 phases. Microstructure analysis indicates that Al2O3 particles tend to disperse on the grain boundaries. Application of a moderate pressure of 35 MPa at 1200℃ yields Al2O3/tiAl composites with fine Al2O3 reinforcement and a discontinuous network linking by Al2O3 particles. the aluminide component has a fine submicron γ ＋α2 lamellar microstructure. With increasing Nb2O5 content, Al2O3 particles are dispersed uniformly in the matrix. the hardness of the composites increases gradually, and the bending strength and fracture toughness of the composites reach to the maximum value, respectively.

关键词： Al2 O3/tiAl composites Microstructure Mechanical properties

Effect of Aluminum on FOX-7 Structure

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火炸药学报 2019年第3期42卷 223-231,I0001页

作者： Lemi türker Middle East technical University Department of Chemistry üniversiteler

the effect of aluminum on FOX-7 structure was considered. Density functional approach at the level of unrestricted B3LYP/6-311++G(d,p) level was adopted. the model considered 1-4 aluminum atoms per FOX-7 molecule. the results show that the molecular geometries as well as many molecular orbital characteristics of FOX-7 molecule are subjected multiplicity of the composites, FOX-7 + n Al ( n =1-4). In the case of n =1-2, some conformational changes occur. In the presence of three aluminum atoms, the quartet state of the composite is stable but in the doublet state, one of the N—O bonds ruptures. As for the n =4 case the singlet and triplet states are stable but in the quintet state one of the N—O bonds cleaves. As the number of aluminum atoms increases, the HOMO-LUMO energy gap decreases generally.

关键词： FOX-7 1,1-diamino-2,2-dinitroethylene DADNE explosives aluminum DFt

Effect of Magnesium Atom on CL-20------A DFt treatment

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火炸药学报 2017年第6期40卷 17-22页

作者： Lemi türker Department of Chemistry Universiteler Middle East Technical University Ankara Turkey 06231

the effect of magnesium atom on 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtizane(HNIW,CL-20)explosive is considered within the constraints of density functional theory at the level of B3LYP/6-31++G(d,p).the Mg atom transfers some electron population to CL-20and one of the nitro groups linked to 6-membered piperazine ring system(base)is expelled in the prenitrite *** total Mulliken charges on the NO2group reveals that the respective nitramine bond in CL-20is the most susceptible one to *** calculated IR and UV-VIS spectra are *** effect of Mg atom on the molecular orbital energies,especially the HOMO and LUMO has been *** of the interfrontier molecular orbital energy gap(Δε)in the composite system ***,the composite system is more susceptible to impact compared to CL-20.

关键词： CL-20 hexanitro hexaazaisowurtizane explosives magnesium density functional theory

Effect of size on biaxial flexural strength for cement-based materials by using a triangular plate method

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Frontiers of Structural and Civil Engineering 2022年第8期16卷 1017-1028页

作者： Hakan t tURKER Department of Civil Engineering Bursa Uludag UniversityBursa 16059Turkey

the effect of size on the biaxial flexural strength(BFS)of Portland cement mortar was investigated by using the recently proposed triangular plate method(tPM).An experimental program was conceived to study the size effect by keeping a constant water-cement ratio of 0.485,cement-sand ratio of 1:2.75,and using unreinforced triangular mortar plates of five different thicknesses and seven different side *** BFS of the produced specimens was tested,and variations of BFS depending on specimen thickness and side length were *** results indicated that increases in triangular plate specimen side length and specimen thickness led to a decrease in the BFS of Portland cement *** effect of specimen length increase on BFS was more significant than on the effect of the specimen *** variations in specimens’thickness indicated a deterministic type I size effect,while the variations in specimens’length showed an energetic-statistical type I size effect.

关键词： testing apparatus&methods plain concrete tensile properties biaxial flexural strength triangular plate method