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Toward More Culturally Inclusive Domestic Interiors in the Age of Global Mobility
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作者 Sondos Rawas 《Journal of Civil Engineering and Architecture》 2022年第2期91-108,共18页
Global modernity,mobility and movement stand as characteristic features that are shaping current times.Marking and challenging the notion of identity,whether cultural,religious,or political,on a daily basis,is movemen... Global modernity,mobility and movement stand as characteristic features that are shaping current times.Marking and challenging the notion of identity,whether cultural,religious,or political,on a daily basis,is movement from nation to nation,region to region,city to city.Individuals and groups are overcoming and crossing geographical borders and cultural differences for study,tourism,lifestyle,or even to start a new life with their children.Thus,identity can be challenged and redefined,resulting in a hybrid identity.The concept of interiors,especially domestic interiors,while people are moving and stopping has changed and is still changing.This case study was based in the city of Glasgow in the UK,where a qualitative approach was adopted for the study of 20 Arab Muslim participants.Semi-structured interviews were conducted within their current private houses in Glasgow. 展开更多
关键词 Domestic interiors contemporary immigration MOBILITY Arabic Islamic culture design ethnography
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Experimental research on the launching system of auxiliary charge with filter cartridge structure
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作者 Zi-Jun Chen Ze He +2 位作者 Hong-Hao Ma Lu-Qing Wang Zhao-Wu Shen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期41-48,共8页
A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the projectile.The combustion chamber of the launching system is divided into two fixed chambers,one is located in th... A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the projectile.The combustion chamber of the launching system is divided into two fixed chambers,one is located in the breech chamber,and the other is arranged in the barrel.The breech chamber charge was ignited first,and the charges in the auxiliary chambers were ignited by the high-temperature,highpressure combustible gas trailing the projectile.In this way,the combustible gas in the auxiliary chambers could compensate for the pressure drop caused by the movement of the projectile.The proposed device features the advantage of launching a projectile with high muzzle velocity without exceeding the maximum pressure in the chamber.In order to obtain some internal ballistic characteristics of the launch system,some critical structure,such as the length of the filter cartridge auxiliary charge,the combustion degree of the propellant in the chamber,and the length of the barrel,are discussed.The experimental results show that with the increased auxiliary charge length,a pressure plateau or even a secondary peak pressure can be formed,which is less than the peak pressure.The projectile velocity increased by 23.57%,14.64%,and 7.65%when the diaphragm thickness was 0 mm,1 mm,and2 mm,respectively.The muzzle velocity of the projectile can be increased by 13.42%by increasing the length of the barrel.Under the same charge condition,with the increase of barrel length,the energy utilization rate of propellant increases by 28.64%. 展开更多
关键词 Interior ballistics Charge structures Launch system Charge design
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Carbon emission reduction: Contribution of geothermal energy and practice in China
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作者 Liang Wang Li-qiong Jia 《China Geology》 CAS CSCD 2024年第1期161-164,共4页
As a kind of natural energy from the earth’s interior,geothermal energy is characterized by large reserve,wide distribution,good stability,high utilization coefficient,and positive effects of energy-saving and emissi... As a kind of natural energy from the earth’s interior,geothermal energy is characterized by large reserve,wide distribution,good stability,high utilization coefficient,and positive effects of energy-saving and emission-reduction.It is of great significance for promoting green and low-carbon energy transition,reducing greenhouse gas emission,and achieving global climate goals and sustainable economic development.Hence,it has been highly recognized and valued by lots of countries around the world,and has become one of the most important clean energy sources that countries are accelerating to develop and utilize.The potential of the global geothermal energy resource is estimated to be 1.25×1027 J,equivalent to 4.27×10^(16) t of standard coal,among which the geothermal resource between 0 km and 5 km is 1.45×10^(26) J,equivalent to 4.95×1015 t of standard coal(China Geological Survey,2018). 展开更多
关键词 ENERGY utilize INTERIOR
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A novel approach of jet polishing for interior surface of small-grooved components using three developed setups
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作者 Qinming Gu Zhenyu Zhang +6 位作者 Hongxiu Zhou Jiaxin Yu Dong Wang Junyuan Feng Chunjing Shi Jianjun Yang Junfeng Qi 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期428-447,共20页
It is a challenge to polish the interior surface of an additively manufactured component with complex structures and groove sizes less than 1 mm.Traditional polishing methods are disabled to polish the component,meanw... It is a challenge to polish the interior surface of an additively manufactured component with complex structures and groove sizes less than 1 mm.Traditional polishing methods are disabled to polish the component,meanwhile keeping the structure intact.To overcome this challenge,small-grooved components made of aluminum alloy with sizes less than 1 mm were fabricated by a custom-made printer.A novel approach to multi-phase jet(MPJ)polishing is proposed,utilizing a self-developed polisher that incorporates solid,liquid,and gas phases.In contrast,abrasive air jet(AAJ)polishing is recommended,employing a customized polisher that combines solid and gas phases.After jet polishing,surface roughness(Sa)on the interior surface of grooves decreases from pristine 8.596μm to 0.701μm and 0.336μm via AAJ polishing and MPJ polishing,respectively,and Sa reduces 92%and 96%,correspondingly.Furthermore,a formula defining the relationship between linear energy density and unit defect volume has been developed.The optimized parameters in additive manufacturing are that linear energy density varies from 0.135 J mm^(-1)to 0.22 J mm^(-1).The unit area defect volume achieved via the optimized parameters decreases to 1/12 of that achieved via non-optimized ones.Computational fluid dynamics simulation results reveal that material is removed by shear stress,and the alumina abrasives experience multiple collisions with the defects on the heat pipe groove,resulting in uniform material removal.This is in good agreement with the experimental results.The novel proposed setups,approach,and findings provide new insights into manufacturing complex-structured components,polishing the small-grooved structure,and keeping it unbroken. 展开更多
关键词 abrasive air jet polishing multi-phase jet polishing interior curved surface small-grooved component aluminum alloy
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On Multi-Granulation Rough Sets with Its Applications
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作者 Radwan Abu-Gdairi R.Mareay M.Badr 《Computers, Materials & Continua》 SCIE EI 2024年第4期1025-1038,共14页
Recently,much interest has been given tomulti-granulation rough sets (MGRS), and various types ofMGRSmodelshave been developed from different viewpoints. In this paper, we introduce two techniques for the classificati... Recently,much interest has been given tomulti-granulation rough sets (MGRS), and various types ofMGRSmodelshave been developed from different viewpoints. In this paper, we introduce two techniques for the classificationof MGRS. Firstly, we generate multi-topologies from multi-relations defined in the universe. Hence, a novelapproximation space is established by leveraging the underlying topological structure. The characteristics of thenewly proposed approximation space are discussed.We introduce an algorithmfor the reduction ofmulti-relations.Secondly, a new approach for the classification ofMGRS based on neighborhood concepts is introduced. Finally, areal-life application from medical records is introduced via our approach to the classification of MGRS. 展开更多
关键词 Multi-granulation rough sets data classifications information systems interior operators closure operators approximation structures
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THE INTERIOR TRANSMISSION EIGENVALUE PROBLEM FOR AN ANISOTROPIC MEDIUM BY A PARTIALLY COATED BOUNDARY
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作者 向建立 严国政 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期339-354,共16页
We consider the interior transmission eigenvalue problem corresponding to the scattering for an anisotropic medium of the scalar Helmholtz equation in the case where the boundary?Ωis split into two disjoint parts and... We consider the interior transmission eigenvalue problem corresponding to the scattering for an anisotropic medium of the scalar Helmholtz equation in the case where the boundary?Ωis split into two disjoint parts and possesses different transmission conditions.Using the variational method,we obtain the well posedness of the interior transmission problem,which plays an important role in the proof of the discreteness of eigenvalues.Then we achieve the existence of an infinite discrete set of transmission eigenvalues provided that n≡1,where a fourth order differential operator is applied.In the case of n■1,we show the discreteness of the transmission eigenvalues under restrictive assumptions by the analytic Fredholm theory and the T-coercive method. 展开更多
关键词 interior transmission eigenvalue anisotropic medium partially coated boundary the analytic Fredholm theory T-coercive method
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Variability of the Pacific subtropical cells under global warming in CMIP6 models
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作者 Xue HAN Junqiao FENG +1 位作者 Yunlong LU Dunxin HU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期24-40,共17页
The Pacific subtropical cells(STCs)are shallow meridional overturning circulations connecting the tropics and subtropics,and are assumed to be an important driver of the tropical Pacific decadal variability.The variab... The Pacific subtropical cells(STCs)are shallow meridional overturning circulations connecting the tropics and subtropics,and are assumed to be an important driver of the tropical Pacific decadal variability.The variability of STCs under global warming is investigated using multimodal outputs from the latest phase of the Coupled Model Inter-comparison Project(CMIP6)and ocean reanalysis products.Firstly,the volume transport diagnostic analysis is employed to evaluate how coupled models and ocean reanalysis products reproduce interior STC transport.The variation of heat transport by the interior STC under the high-emissions warming scenarios is also analyzed.The results show that the multimodal-mean linear trends of the interior STC transport along 9°S and 9°N are-0.02 Sv/a and 0.04 Sv/a under global warming,respectively,which is mainly due to the combined effect of the strengthened upper oceanic stratification and the weakening of wind field.There is a compensation relationship between the interior STC and the western boundary transport in the future climate,and the compensation relationship of 9°S is more significant than that of 9°N.In addition,compared with ocean reanalysis products,the coupled models tend to underestimate the variability of the interior STC transport convergence,and thus may lose some sea surface temperature(SST)driving force,which may be the reason for the low STC-SST correlation simulated by the model.The future scenario simulation shows that the heat transport of interior STC is weakened under global warming,with a general agreement across models. 展开更多
关键词 interior subtropical cell(STC) global warming Coupled Model Inter-comparison Project(CMIP6) western boundary transport
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Ordovician reservoirs in Fuxian area:Gas accumulation patterns and their implications for the exploration of lower Paleozoic carbonates in the southern Ordos Basin
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作者 Ning Gu Juntao Zhang +2 位作者 Xiaohui Jin Fei Yang Lu Liu 《Energy Geoscience》 EI 2024年第1期63-71,共9页
In recent years,the Fuxian area in the southeastern Ordos Basin has undergone significant exploration,with industrial gas flow tested in wells drilled into the Ordovician marine carbonates.Despite this,the gas accumul... In recent years,the Fuxian area in the southeastern Ordos Basin has undergone significant exploration,with industrial gas flow tested in wells drilled into the Ordovician marine carbonates.Despite this,the gas accumulation patterns of this area are not fully understood,posing challenges for further exploration.Our analysis of geological conditions indicates that the Ordovician Majiagou Formation in this area hosts two gas plays:one found in weathering crusts and the other found in interior of the formation.We investigated various typical gas reservoirs in the area,focusing on differentiating the geological conditions and factors controlling gas accumulation in the weathering-crust and interior gas reservoirs.The results suggest three primary gas accumulation patterns in the Majiagou Formation in the Fuxian area:(1)upper gas accumulation in weathering crusts,present in the high parts of landforms such as residual paleo-hills or buried paleo-platform(Pattern I);(2)the stereoscopic pattern with gas accumulation in both weathering crusts and strata interior,arising in high parts of landforms such as residual paleo-hills or buried paleo-platforms(Pattern II);(3)lower gas accumulation in strata interior,occurring in the upper reaches and on both sides of paleo-trenches(Pattern III).This study will serve as a geological basis for future exploration deployment in the Fuxian area. 展开更多
关键词 Gas accumulation ORDOVICIAN Weathering crust play Interior play Fuxian area The ordos basin
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Persistent mixing bursts in the equatorial Pacific thermocline induced by persistent equatorial waves
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作者 Jingjing ZHANG Chuanyu LIU +1 位作者 Xiang GONG Fan WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期492-510,共19页
A recent study by Liu et al.(2020)suggested that due to the saturation of equatorially trapped planetary waves with different dynamical types,temporal periods,meridional and baroclinic modes,complex layer structures o... A recent study by Liu et al.(2020)suggested that due to the saturation of equatorially trapped planetary waves with different dynamical types,temporal periods,meridional and baroclinic modes,complex layer structures of vertical velocity shear and hence turbulent mixing could frequently occur in the thermocline of the eastern equatorial Pacific.We investigated the occurrence of the interior turbulent mixing as indicated by shear instabilities,above the Equatorial Undercurrent(EUC)core at three equatorial sites along 140°W,170°W,and 165°E,respectively,based mainly on data from the Tropical Atmosphere and Ocean(TAO)mooring array.We found that turbulent mixing bursts persisted in the thermocline of all three sites.Specifically,the interior turbulent mixing layers(ITMLs)could occur in probability of approximately 68%,53%,and 48%at the three sites,respectively.The overall occurrence probability shows obvious and similar biannual variations at 140°W and 170°W,which is higher in boreal from late summer to winter and lower in spring.Vertically,the ITMLs are primarily located above the EUC core and prevail in deeper(shallower)layers from late summer to winter(spring).Most ITMLs(70%)lasted for hours to 3 days,and a few of them(15%)for more than 7 days.The thicknesses of ITMLs were concentrated between 15 and 55 m.At 165°E,the vertical distribution of ITML occurrence probability was different from that at 140°W and 170°W,as it did not show a preference for depths;the durations of ITMLs are short(also from hours to several days)and their thicknesses were between 5 and 25 m.These properties,particularly the high occurrence probability,and short durations demonstrated the persistence of thermocline mixing in the western to eastern equatorial Pacific thermocline and confirmed the generation mechanism by persistent equatorial waves as well. 展开更多
关键词 interior turbulent mixing layer(ITML) weakly sheared layer(WSL) Equatorial Undercurrent(EUC)core occurrence probability SEASONALITY
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凸F-多边形内部的F-点数
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作者 郭自欢 魏祥林 《Chinese Quarterly Journal of Mathematics》 2024年第1期46-58,共13页
An F-polygon is a simple polygon whose vertices are F-points, which are points of the set of vertices of a tiling of R~2 by regular triangles and regular hexagons of unit edge. Let f(v) denote the least possible numbe... An F-polygon is a simple polygon whose vertices are F-points, which are points of the set of vertices of a tiling of R~2 by regular triangles and regular hexagons of unit edge. Let f(v) denote the least possible number of F-points in the interior of a convex F-polygon K with v vertices. In this paper we prove that f(10) = 10, f(11) = 12,f(12) = 12. 展开更多
关键词 Discrete geometry F-polygon Interior hull Lattice polygon
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A novel DPSS filter optimization scheme to reduce the intrinsic interference of FBMC-QAM systems
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作者 董琪阳 MA Tianming +1 位作者 JIN Jie WU Zhong 《High Technology Letters》 EI CAS 2024年第1期68-74,共7页
In order to reduce the intrinsic interference of the filter bank multicarrier-quadrature amplitude modulation(FBMC-QAM)system,a novel filter optimization scheme based on discrete prolate spheroidal sequences(DPSS)is p... In order to reduce the intrinsic interference of the filter bank multicarrier-quadrature amplitude modulation(FBMC-QAM)system,a novel filter optimization scheme based on discrete prolate spheroidal sequences(DPSS)is proposed.Firstly,a prototype filter function based on DPSS is designed,since the eigenvalue can be used as an indicator of the energy concentration of DPSS,so a threshold is set,and the sequence with the most concentrated energy is selected under the threshold,that is,the sequence with the eigenvalue higher than the threshold,and the prototype filter function is rewritten as a weighted sum function of multiple eigenvectors.Under the energy constraints of the filter,the relationship between the eigenvectors and the intrinsic interference function is established,and the function problem is transformed into an optimization problem for the weighted coefficients.Through the interior point method,the most suitable weight is found to obtain the minimum intrinsic interference result.Theoretical analysis and simulation results show that compared with the prototype filters such as Type1 and CaseC,the DPSS filter applying the proposed optimization algorithm can effectively suppress the intrinsic interference of the system and obtain a better bit error rate(BER)performance. 展开更多
关键词 filter bank multicarrier-quadrature amplitude modulation(FBMC-QAM) intrinsic interference discrete prolate spheroidal sequences(DPSS) interior point method
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Beta decay of nuclide ^(56)Fe,^(56)Co,^(56)Ni,^(56)Mn,^(56)Cr and ^(56)V due to strong electron screening in stellar interiors
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作者 刘晶晶 《Chinese Physics C》 SCIE CAS CSCD 2010年第11期1700-1703,共4页
According to a new electron screening theory,we discuss the beta decay rates of nuclide 56Fe,56Co,56Ni,56Mn,56Cr and 56V with and without strong electron screening (SES).The results show that SES has only a slight e... According to a new electron screening theory,we discuss the beta decay rates of nuclide 56Fe,56Co,56Ni,56Mn,56Cr and 56V with and without strong electron screening (SES).The results show that SES has only a slight effect on the beta decay rates for ρ/μe 108 g/cm3.However the beta decay rates would be influenced greatly for ρ/μe 108 g/cm3.Due to SES,the maximum values of the C-factor (in %) on beta decay rates of 56Fe,56Co,56Ni,56Mn,56Cr and 56V is of the order of 95.03%,35.02%,98.05%,80.33%,98.30% and 98.71% at T9 = 4.0 and 98.83%,98.89%,99.65%,10.32%,4.10% and 40.21% at T9 = 7.0,respectively. 展开更多
关键词 beta decay stellar interiors strong electron screening
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Introduction to the JES Special Issue on “Multiple-Scale Geodynamics of Continental Interiors”
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作者 Zhou Huawei 《Journal of Earth Science》 SCIE CAS CSCD 2011年第2期I0002-I0002,共1页
A major mission of geosciences is to characterize the composition, structure and geodynamic history of the earth's continental interiors. Because the evidence for such studies is spread over different disciplines and... A major mission of geosciences is to characterize the composition, structure and geodynamic history of the earth's continental interiors. Because the evidence for such studies is spread over different disciplines and in different spatial and temporal scales, advances in understanding the geodynamics of continental interiors often require a multi-disciplinary approach to examine the multiplescale nature of the subjects. 展开更多
关键词 Multiple-Scale Geodynamics of Continental interiors
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Halide ion-induced formation of single crystalline mesoporous PtPd bimetallic nanoparticles with hollow interiors for electrochemical methanol and ethanol oxidation reaction 被引量:2
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作者 Pengtao Qiu Shaomin Lian +1 位作者 Guang Yang Shengchun Yang 《Nano Research》 SCIE EI CAS CSCD 2017年第3期1064-1077,共14页
We demonstrate a facile hydrothermal one-pot synthesis method for producing single crystalline mesoporous PtPd bimetallic nanoparticles with a hollow interior and porous surface structure in the presence of Br- and F ... We demonstrate a facile hydrothermal one-pot synthesis method for producing single crystalline mesoporous PtPd bimetallic nanoparticles with a hollow interior and porous surface structure in the presence of Br- and F ions. The formation process analysis indicated that the coexistence of Br- and I- ions is responsible for the formation of the novel bimetallic nanoparticles. The changes in the reduction potential of Pt and Pd metal ions achieved by the coordination with different halide ions resulted in the formation of hollow interiors as a galvanic reaction between Pd2~ and Pt4. ions occurred. In addition, the size of the mesoporous PtPd nanoparticles can be well controlled by slightly changing the amount of I- ions used. The electrochemical tests indicated that the as- synthesized single crystalline mesoporous PtPd hollow nanoparticles exhibited enhanced catalytic properties toward methanol and ethanol oxidation reactions as compared with the commercial Pt black and Pt/C materials. 展开更多
关键词 noble metalmesoporous single crystal hollow interior ELECTROCATALYSIS
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Dynamical machine learning volumetric reconstruction of objects’ interiors from limited angular views 被引量:2
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作者 Iksung Kang Alexandre Goy George Barbastathis 《Light(Science & Applications)》 SCIE EI CAS CSCD 2021年第5期824-844,共21页
Limited-angle tomography of an interior volume is a challenging, highly ill-posed problem with practical implications in medical and biological imaging, manufacturing, automation, and environmental and food security. ... Limited-angle tomography of an interior volume is a challenging, highly ill-posed problem with practical implications in medical and biological imaging, manufacturing, automation, and environmental and food security. Regularizing priors are necessary to reduce artifacts by improving the condition of such problems. Recently, it was shown that one effective way to learn the priors for strongly scattering yet highly structured 3D objects, e.g. layered and Manhattan, is by a static neural network [Goy et al. Proc. Natl. Acad. Sci. 116, 19848–19856 (2019)]. Here, we present a radically different approach where the collection of raw images from multiple angles is viewed analogously to a dynamical system driven by the object-dependent forward scattering operator. The sequence index in the angle of illumination plays the role of discrete time in the dynamical system analogy. Thus, the imaging problem turns into a problem of nonlinear system identification, which also suggests dynamical learning as a better fit to regularize the reconstructions. We devised a Recurrent Neural Network (RNN) architecture with a novel Separable-Convolution Gated Recurrent Unit (SC-GRU) as the fundamental building block. Through a comprehensive comparison of several quantitative metrics, we show that the dynamic method is suitable for a generic interior-volumetric reconstruction under a limited-angle scheme. We show that this approach accurately reconstructs volume interiors under two conditions: weak scattering, when the Radon transform approximation is applicable and the forward operator well defined;and strong scattering, which is nonlinear with respect to the 3D refractive index distribution and includes uncertainty in the forward operator. 展开更多
关键词 INTERIOR DYNAMICAL ANGULAR
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A MODEL LIVING SPACE Timing Homes Ideal Interiors
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作者 Tristin Zhang 《城市漫步(GBA版)》 2017年第5期19-19,共1页
If you are fascinated by the trend of minimalism,then a neat and artsy living space is what you'll ultimately strive to be maintain.To succeed,however,a certain amount of daily attention is crucial-ie.picking up c... If you are fascinated by the trend of minimalism,then a neat and artsy living space is what you'll ultimately strive to be maintain.To succeed,however,a certain amount of daily attention is crucial-ie.picking up clothes off the floor-as is making a consistent effort to cultivate your taste.In other words,you'll need to bridge the gap between what you envision for your interior and what your room actually looks like,which is typically much harder than it sounds. 展开更多
关键词 SPACE MAINTAIN INTERIOR
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Asteroseismology of 16 Kepler Solar-like Stars:Stellar Parameters and the Effects of Element Diffusion
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作者 Shuai Wang Qian-Sheng Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第7期206-220,共15页
Element diffusion has small but significant effects on the structure of the stellar interior.It is interesting to investigate the effects of element diffusion using asteroseismology.We have constructed two grids of st... Element diffusion has small but significant effects on the structure of the stellar interior.It is interesting to investigate the effects of element diffusion using asteroseismology.We have constructed two grids of stellar models,one with diffusion and one without,for solar-like stars with masses between 0.9 and 1.4 solar masses,and varied initial helium abundance and metallicity.The oscillation frequencies of all stellar models have also been calculated.Piecewise Hermite cubic polynomials are adopted to interpolate stellar p-mode frequencies at an arbitrary age on a stellar evolutionary track.We have investigated 16 Kepler solar-like stars by comparing the model frequencies with observations.The suggested ranges of stellar parameters and some global variables are obtained.For all stars,the best model reproduces the observational frequencies with aχ^(2)of the order of unity.It has been found that element diffusion is important in modeling solar-like stars.Without diffusion,the best value of the initial helium abundance is below the primordial helium abundance from Big Bang nucleosynthesis.When diffusion is taken into account,the required initial helium abundance increases to be higher than the primordial abundance.Diffusion also generally improves the frequency fitting results by reducing the minimum ofχ^(2).Investigation of the second difference of the oscillation frequencies on KIC 8694723 and KIC 10454113 indicates that the current model of element diffusion may underestimate the strength of settling. 展开更多
关键词 ASTEROSEISMOLOGY DIFFUSION stars:interiors stars:abundances
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A Linear Operator Method to Compute the Normal Modes with Rotation of any Asymmetric 3D Planet with Pure Vector Spherical Harmonics
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作者 Mian Zhang Cheng-Li Huang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第10期224-254,共31页
In order to compute the free core nutation of the terrestrial planets, such as Earth and Mars, the Moon and lower degree normal modes of the Jovian planets, we propose a linear operator method(LOM). Generalized surfac... In order to compute the free core nutation of the terrestrial planets, such as Earth and Mars, the Moon and lower degree normal modes of the Jovian planets, we propose a linear operator method(LOM). Generalized surface spherical harmonics(GSSHs) are usually applied to the elliptical models with a stress tensor, which cannot be expressed in vector spherical harmonics explicitly. However, GSSHs involve complicated math. LOM is an alternative to GSSHs,whereas it only deals with the coupling fields of the same azimuthal order m, as is the case when a planet model is axially symmetric and rotates about that symmetry axis. We extend LOM to any asymmetric 3D model. The lower degree spheroidal modes of the Earth are computed to validate our method, and the results agree very well with what is observed. We also compute the normal modes of a two-layer Saturn model as a simple application. 展开更多
关键词 planets and satellites:interiors Earth planets and satellites:gaseous planets
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Serpentinisation is Required for the Magnetization of the Martian Crust
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作者 Shuoran Yu Dongdong Ni 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第6期134-142,共9页
The remnant magnetism in the crust of Martian southern highland is associated with the magnetic sources at an average depth of~32 km.In this work,we investigate the magnetization of Martian crust via 1-D parameterized... The remnant magnetism in the crust of Martian southern highland is associated with the magnetic sources at an average depth of~32 km.In this work,we investigate the magnetization of Martian crust via 1-D parameterized model for the stagnant-lid mantle convection.According to our model,the magnetization of Martian crust is likely to take place in the top-down manner during 4.1-3.7 Ga.To reproduce the average depth of magnetic sources below the southern highland,magnetite and Mg-ferrite are anticipated to be the magnetic carriers in the Martian crust,implying the serpentinisation therein.If magnetite is the only magnetic carrier in the Martian crust,the early climate must be warm enough to maintain a surface temperature of 300 K during 4.1-3.7 Ga at least.Such a warm climate is more likely to be a regional phenomenon associated with the serpentinisation in the crust of the southern highland or the hot ejecta of Borialis impact depositing on the southern hemisphere. 展开更多
关键词 planets and satellites:interiors planets and satellites:magnetic fields planets and satellites:terrestrial planets
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Temperature influences of the recoil characteristics for aluminum honeycomb buffer in the tether-net launcher 被引量:1
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作者 Wen-hui Shi Shuai Yue +5 位作者 Chun-bo Wu Zhou Liu Zhi Liu Bei-bei Zhao Zhong-hua Du Guang-fa Gao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第11期39-54,共16页
Fluctuations in outer space's temperature would affect the spacecraft's regular operation.This paper aims to study the temperature influences of the aluminum honeycomb buffer in the tether-net launcher.Firstly... Fluctuations in outer space's temperature would affect the spacecraft's regular operation.This paper aims to study the temperature influences of the aluminum honeycomb buffer in the tether-net launcher.Firstly,a buffer structure was designed to attenuate the pyroshock generated by the pyrotechnic device.Secondly,the mechanical properties of aluminum honeycomb at different temperatures were obtained through quasi-static compression experiments.Then,the internal ballistic responses of the launcher were gained by the closed bomb tests and the equivalent classical interior ballistic model.Finally,the recoil performance of the launcher with aluminum honeycomb buffer at different temperatures was studied.It is revealed that the aluminum honeycomb crushing force gradually decreases with the temperature increases.The peak pressure,burning rate coefficient and velocity increase while the peak time decreases with the temperature increase for the interior ballistics.For the launcher recoil responses,the average launch recoil decreases if the aluminum honeycomb doesn't enter the dense stage.The impact acceleration,projectile velocity and displacement increase as the temperature increase.The paper spotlights the temperature's influence on the recoil characteristics of the aluminum honeycomb buffer,which provides a new idea for buffering technology of pyrotechnic devices in a complex space environment. 展开更多
关键词 Tether-net launcher Temperature Aluminum honeycomb buffer Interior ballistic responses Launch recoil characteristics
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