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信息安全与通信保密 1981年第1期 42-52页

作者： n.r.f.mackinnon 梁之

本文考查了一些过去和目前使用的话音加密原理。数字逻辑系统和集成电路器件的出现被看作是使有效加密原理得以实现的一个重要转折点,而在这以前是不可能满意地利用这些原理的。

关键词：话音质量保密度数字输出白噪音加密器密钥产生器频域置乱

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

Lattice thermal conduction in cadmium arsenide

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Chinese Physics B 2022年第11期31卷 424-430页

作者： r f Chinnappagoudra M D Kamatagi n r Patil n S Sankeshwar Department of Physics S.S.Government First Grade CollegeNargund-582207KarnatakaIndia research resource Centre Visvesvaraya Technological UniversityBelagavi-590018KarnatakIndia Department of Physics B V B College of Engineering and TechnologyHubliKarnataka 80031India Department of Physics&Electronics CHRIST(Deemed to be University)Bangalore-560029KarnatakaIndia

Lattice thermal conductivity(LTC)of cadmium arsenide(Cd_(3)As_(2))is studied over a wide temperature range(1–400 K)by employing the Callaway *** acoustic phonons are considered to be the major carriers of heat and to be scattered by the sample boundaries,disorder,impurities,and other phonons via both Umklapp and normal phonon *** calculations of LTC of Cd_(3)As_(2)bring out the relative importance of the scattering *** systematic analysis of recent experimental data on thermal conductivity(TC)of Cd_(3)As_(2)samples of different groups,presented in terms of LTC,κL,using a nonlinear regression method,reveals good fits to the TC data of the samples considered for Tnd suggests a value of 0.2 for the Gruneisen *** is,however,found that for T>100 K the inclusion of the electronic component of TC,κe,incorporating contributions from relevant electron scattering mechanisms,is needed to obtain good agreement with the TC data over the wide temperature *** detailed investigations of TC of Cd_(3)As_(2)are required to better understand its suitability in thermoelectric and thermal management devices.

关键词： dirac semimetals Cd_(3)As_(2) thermal conductivity phonon scattering

Effects of Strain rate and Deformation Temperature on Microstructures and Hardness in Plastically Deformed Pure Aluminum

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Journal of Materials Science & Technology 2011年第1期27卷 1-7页

作者： f. Huang n.r. Taot K. Lu Shenyang national Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang110016 China

The microstructures and hardness of pure Al samples subjected to plastic deformation with different tem- peratures and strain rates were investigated. The results showed that the strain-induced grain refinement is significantly benefited by increasing strain rate and reducing deformation temperature. The saturated size of refined subgrains in Al can be as small as about 240 nm in cryogenic dynamic plastic deformation （DPD）. Grain boundaries of the DPD Al samples are low-angle boundaries due to suppression of dynamic recovery during deformation. Agreement of the measured hardness with the empirical Hall-Petch relation extrapolated from the coarse-grained Al implies that the low-angle boundaries can contribute to strengthening as effective as the conventional grain boundaries.

关键词： Dynamic plastic deformation Microstructure Hardness Strain rate Temperature

numerical solutions for cracks in an elastic half-plane

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Acta Mechanica Sinica 2019年第1期35卷 212-227,I0006页

作者： n.r.f.Elfakhakhre n.M.A.nik Long Z.K.Eshkuvatov Mathematics Department Faculty of ScienceUniversiti Putra Malaysia43400 SerdangSelangorMalaysia Institute for Mathematical research Universiti Putra Malaysia43400 SerdangSelangorMalaysia faculty of Science and Technology Universiti Sains Islam Malaysia71800 NilaiNegeri SembilanMalaysia

The behavior of the stress intensity factor at the tips of cracks subjected to uniaxial tension σχ^∞= p with traction-free boundary condition in half-plane elasticity is investigated. The problem is formulated into singular integral equations with the distribution dislocation function as unknown. In the formulation, we make used of a modified complex potential. Based on the appropriate quadrature formulas together with a suitable choice of collocation points, the singular integral equations are reduced to a system of linear equations for the unknown coefficients. numerical examples show that the values of the stress intensity factor are influenced by the distance from the cracks to the boundary of the half-plane and the configuration of the cracks.

关键词： Elastic half-plane Multiple cracks Singular integral equation Sine-shaped crack

Effects of Impurity on Microstructure and Hardness in Pure Al Subjected to Dynamic Plastic Deformation at Cryogenic Temperature

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Journal of Materials Science & Technology 2011年第7期27卷 628-632页

作者： f. Huang n.r. Tao K. Lu Shenyang national Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Microstructure and hardness were investigated in pure Al samples with different purities （5n： 99.999%, 4n： 99.993%, and 2n： 99.7% in weight） subjected to dynamic plastic deformation at cryogenic temperatures. The saturated sizes of refined grains/subgrains in these samples induced by plastic deformation are about 240 nm without an obvious impurity effect, but the dislocation density in 2n Al is evidently higher than that in other samples. Boundary misorientations for 5n and 4n Al are below 10° with average values of 2–3°, while the average misorientation for 2n Al is obviously larger, being about 14°. Microhardness of LnT-DPD 2n Al is higher than that of 5n and 4n Al, owing to the enhanced dislocation density as their grain/subgrain sizes are almost identical.

关键词： Aluminum Impurity nanostructure Grain refinement

novel design concepts for network intrusion systems based on dendritic cells processes

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Journal of Central South University 2013年第8期20卷 2175-2185页

作者： rICHArD M r 谭冠政 OnGALO P n f CHErUIYOT W School of Information Science and Engineering Central South University

An abstraction and an investigation to the worth of dendritic cells (DCs) ability to collect, process and present antigens are presented. Computationally, this ability is shown to provide a feature reduction mechanism that could be used to reduce the complexity of a search space, a mechanism for development of highly specialized detector sets as well as a selective mechanism used in directing subsets of detectors to be activated when certain danger signals are present. It is shown that DCs, primed by different danger signals, provide a basis for different anomaly detection pathways. Different antigen-peptides are developed based on different danger signals present, and these peptides are presented to different adaptive layer detectors that correspond to the given danger signal. Experiments are then undertaken that compare current approaches, where a full antigen structure and the whole repertoire of detectors are used, with the proposed approach. Experiment results indicate that such an approach is feasible and can help reduce the complexity of the problem by significant levels. It also improves the efficiency of the system, given that only a subset of detectors are involved during the detection process. Having several different sets of detectors increases the robustness of the resulting system. Detectors developed based on peptides are also highly discriminative, which reduces the false positives rates, making the approach feasible for a real time environment.

关键词： artificial immune systems network intrusion detection anomaly detection feature reduction negative selectionalgorithm danger model

Multiscale characterization of nanoparticles in a magnetically assisted fluidized bed

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Particuology 2020年第4期18卷 64-71页

作者： f.Karimi M.Haghshenasfard r.Sotudeh-Gharebagh r.Zarghami n.Mostoufi Department of Chemical Engineering Isfahan University of TechnologyP.O.Box ***IsfahanIran School of Chemical Engineering College of EngineeringUniversity of TehranP.O.Box 11155/4563TehranIran

Pressure fluctuations of a fluidized bed of nanoparticles were measured during the fluidization of nanoparticles with and without a magnetic field at a frequency of 50 *** quantification analysis(rQA)and wavelet transform were used to determine the frequency range of various flow structures in the bed at three *** frequency ranges of the macro-,meso-,and micro-structures were determined to be 0-49Hz,49-781 Hz,and 781+Hz,*** of the determinisms of the sub-signals with and without the external field revealed that in the presence the field,breakage of larger agglomerates occurs faster than re-agglomeration of small agglomerates into larger *** power spectral density function of the pressure fluctuations indicated that with an external magnetic field,the power and the frequency range of the pressure signal of macro-structures do not change ***,the power of the meso-structure signal increases and its frequency range is widened toward higher frequencies,confirming that the number of small bubbles and agglomerates increase in the *** addition,the energy of signal analysis indicated that the external field significantly increases the share of meso-structures in the bed,confirming the rQA results.

关键词： nanoparticles fluidized bed Magnetic field Pressure fluctuations recurrence quantification analysis Wavelet transform

Highly electroactive n–fe hydrothermal carbons and carbon nanotubes for the oxygen reduction reaction

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Journal of Energy Chemistry 2020年第11期29卷 260-270页

作者： r.G.Morais n.rey-raap J.L.figueiredo M.f.r.Pereira Associate Laboratory LSrE-LCM Departamento de Engenharia QuimicaFaculdade de EngenhariaUniversidade do PortoR.Dr.Roberto Frias s/n4200-465PortoPortugal

Glucose-derived carbons were prepared by hydrothermal carbonization of glucose followed by carbonization or activation to obtain carbon materials with different microporosities. These microporous carbons and carbon nanotubes(CnTs) were functionalized with melamine and/or iron(Ⅱ) phthalocyanine(fePc)following three different methodologies:(i) functionalization with melamine via thermal treatment,(ii)incorporation of the lowest amount of fePc reported in the literature via incipient wetness impregnation followed by thermal treatment and(iii) functionalization with melamine followed by fe Pc *** chemical and textural characterization of the prepared materials and their electrochemical assessment allowed to understand the role of microporosity in the incorporation of fePc and its effect on the oxygen reduction reaction(Orr). It was observed that fePc was preferentially incorporated inside the porous structure, especially in samples with more developed microporosity. However, functionalization with melamine modified the textural properties and the surface chemistry, favoring the incorporation of fePc on the surface. regarding the electrochemical performance, the presence of fePc greatly enhanced the electroactivity of the microporous catalysts. An onset potential of 0.88 V and a four-electron pathway were obtained for glucose-derived carbons, whereas the limiting current densities and kinetic current densities rose by 126% and 222%, respectively, in comparison to the base sample. notwithstanding, the highest electrochemical activity was observed for the sample prepared with CnTs, due to the synergy between the active metal centers and their highly graphitic carbon structure. The electrochemical parameters of CnTfeP csurpass the commercial Pt/C. The half-wave potential is 40 mV higher, the limiting current density increases by 17%, and a negligible production of by-products(rved.

关键词： Iron(Ⅱ)phthalocyanine Hydrothermal carbons Carbon nanotubes Oxygen reduction reaction Electrocatalysis

Modelling a Skin-Pass rolling Process by Means of Data Mining Techniques and finite Element Method

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Journal of Iron and Steel research International 2012年第5期19卷 43-49页

作者： r Escribano r Lostado f J Martínez-de-Pisón A Pernía E Vergara EDMAnS Group Mechanical Engineering Department of the University of La Rioja Logroo 26004 La Rioja Spain

An experience is presented using the finite element method （fEM） and data mining （DM） techniques to develop models that can be used to optimieze the skin-pass rolling process based on its operating conditions. A fE model based on a real skin-pass process is built and validated. Based on this model, a group of fE models is simulated with different adjustment parameters and with different materials for the sheet; both variables are chosen from pre-set ranges, from all fE model simulations, a database is generated; this database is made up of the above mentioned adjustment parameters, sheet properties and the variables of the process arising from the simulation of the model. Various types of data mining algorithms are used to develop predictive models for each of the variables of the *** best predictive models can be used to predict experimentally hard-to-measure variables （internal stresses, internal straine, etc.） which are useful in the optimal design of the process or to be applied in real time control systems of a skin-pass process in -plant.

关键词： skin-pass rolling predictive model finite element method data mining