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The Soft X-ray Imager(SXI)on the SMILE Mission 被引量:4
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作者 S.Sembay A.L.Alme +83 位作者 D.Agnolon T.Arnold A.Beardmore A.Belén Balado Margeli C.Bicknell C.Bouldin G.Branduardi-Raymont T.Crawford J.P.Breuer T.Buggey G.Butcher R.Canchal J.A.Carter A.Cheney Y.Collado-Vega H.Connor T.Crawford N.Eaton C.Feldman C.Forsyth T.Frantzen G.Galgóczi J.Garcia G.Y.Genov C.Gordillo H-P.Gröbelbauer M.Guedel Y.Guo M.Hailey D.Hall R.Hampson J.Hasiba O.Hetherington A.Holland S-Y.Hsieh M.W.J.Hubbard H.Jeszenszky M.Jones T.Kennedy K.Koch-Mehrin S.Kögl S.Krucker K.D.Kuntz C.Lakin G.Laky O.Lylund A.Martindale J.Miguel Mas Hesse R.Nakamura K.Oksavik N.Østgaard H.Ottacher R.Ottensamer C.Pagani S.Parsons P.Patel J.Pearson G.Peikert F.S.Porter T.Pouliantis B.H.Qureshi W.Raab G.Randal A.M.Read N.M.M.Roque M.E.Rostad C.Runciman S.Sachdev A.Samsonov M.Soman D.Sibeck S.Smit J.Søndergaard R.Speight S.Stavland M.Steller TianRan Sun J.Thornhill W.Thomas K.Ullaland B.Walsh D.Walton C.Wang S.Yang 《Earth and Planetary Physics》 EI CSCD 2024年第1期5-14,共10页
The Soft X-ray Imager(SXI)is part of the scientific payload of the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission.SMILE is a joint science mission between the European Space Agency(ESA)and the Chinese... The Soft X-ray Imager(SXI)is part of the scientific payload of the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission.SMILE is a joint science mission between the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS)and is due for launch in 2025.SXI is a compact X-ray telescope with a wide field-of-view(FOV)capable of encompassing large portions of Earth’s magnetosphere from the vantage point of the SMILE orbit.SXI is sensitive to the soft X-rays produced by the Solar Wind Charge eXchange(SWCX)process produced when heavy ions of solar wind origin interact with neutral particles in Earth’s exosphere.SWCX provides a mechanism for boundary detection within the magnetosphere,such as the position of Earth’s magnetopause,because the solar wind heavy ions have a very low density in regions of closed magnetic field lines.The sensitivity of the SXI is such that it can potentially track movements of the magnetopause on timescales of a few minutes and the orbit of SMILE will enable such movements to be tracked for segments lasting many hours.SXI is led by the University of Leicester in the United Kingdom(UK)with collaborating organisations on hardware,software and science support within the UK,Europe,China and the United States. 展开更多
关键词 soft X-ray Imaging micropore optics large area CCD
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Finding the magnetopause location using soft X-ray observations and a statistical inverse method 被引量:1
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作者 Gonzalo Cucho-Padin Hyunju Connor +2 位作者 Jaewoong Jung Brian Walsh David G.Sibeck 《Earth and Planetary Physics》 EI CSCD 2024年第1期184-203,共20页
Variability in the location and shape of the dayside magnetopause is attributed to magnetic reconnection,a fundamental process that enables the transfer of mass,energy,and momentum from the solar wind into the magneto... Variability in the location and shape of the dayside magnetopause is attributed to magnetic reconnection,a fundamental process that enables the transfer of mass,energy,and momentum from the solar wind into the magnetosphere.The spatial and temporal properties of the magnetopause,under varying solar and magnetospheric conditions,remain largely unknown because empirical studies using in-situ observations are challenging to interpret.Global wide field-of-view(FOV)imaging is the only means to simultaneously observe the spatial distribution of the plasma properties over the vast dayside magnetospheric region and,subsequently,quantify the energy transport from the interplanetary medium into the terrestrial magnetosphere.Two upcoming missions,ESA/CAS SMILE and NASA’s LEXI will provide wide-field imagery of the dayside magnetosheath in soft X-rays,an emission generated by charge exchange interactions between high charge-state heavy ions of solar wind origin and exospheric neutral atoms.High-cadence two-dimensional observations of the magnetosheath will allow the estimation of dynamic properties of its inner boundary,the magnetopause,and enable studies of its response to changes in the solar wind dynamic pressure and interplanetary magnetic field orientation.This work introduces a statistically-based estimation approach based on inverse theory to estimate the spatial distribution of magnetosheath soft X-ray emissivities and,with this,identify the location of the magnetopause over the Sun−Earth line.To do so,we simulate the magnetosheath structure using the MHD-based OpenGGCM model and generate synthetic soft X-ray images using LEXI’s orbit and attitude information.Our results show that 3-D estimations using the described statistically-based technique are robust against Poisson-distributed shot noise inherent to soft X-ray images.Also,our proposed methodology shows that the accuracy of both three-dimensional(3-D)estimation and the magnetopause standoff distance calculation highly depends on the observational point. 展开更多
关键词 MAGNETOPAUSE soft X-ray TOMOGRAPHY
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Estimating the subsolar magnetopause position from soft X-ray images using a low-pass image filter 被引量:1
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作者 Hyangpyo Kim Hyunju K.Connor +9 位作者 Jaewoong Jung Brian M.Walsh David Sibeck Kip D.Kuntz Frederick S.Porter Catriana K.Paw U Rousseau A.Nutter Ramiz Qudsi Rumi Nakamura Michael Collier 《Earth and Planetary Physics》 EI CSCD 2024年第1期173-183,共11页
The Lunar Environment heliospheric X-ray Imager(LEXI)and Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)missions will image the Earth’s dayside magneto pause and cusps in soft X-rays after their respective l... The Lunar Environment heliospheric X-ray Imager(LEXI)and Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)missions will image the Earth’s dayside magneto pause and cusps in soft X-rays after their respective launches in the near future,to specify glo bal magnetic reconnection modes for varying solar wind conditions.To suppo rt the success of these scientific missions,it is critical to develop techniques that extract the magnetopause locations from the observed soft X-ray images.In this research,we introduce a new geometric equation that calculates the subsolar magnetopause position(RS)from a satellite position,the look direction of the instrument,and the angle at which the X-ray emission is maximized.Two assumptions are used in this method:(1)The look direction where soft X-ray emissions are maximized lies tangent to the magnetopause,and(2)the magnetopause surface near the subsolar point is almost spherical and thus RSis nea rly equal to the radius of the magneto pause curvature.We create synthetic soft X-ray images by using the Open Geospace General Circulation Model(OpenGGCM)global magnetohydrodynamic model,the galactic background,the instrument point spread function,and Poisson noise.We then apply the fast Fourier transform and Gaussian low-pass filte rs to the synthetic images to re move noise and obtain accurate look angles for the soft X-ray pea ks.From the filte red images,we calculate RS and its accuracy for different LEXI locations,look directions,and solar wind densities by using the OpenGGCM subsolar magnetopause location as ground truth.Our method estimates RS with an accuracy of<0.3 RE when the solar wind density exceeds>10 cm-3.The accuracy improves for greater solar wind densities and during southward interplanetary magnetic fields.The method ca ptures the magnetopause motion during southwa rd interplaneta ry magnetic field turnings.Consequently,the technique will enable quantitative analysis of the magnetopause motion and help reveal the dayside reconnection modes for dynamic solar wind conditions.This technique will suppo rt the LEXI and SMILE missions in achieving their scientific o bjectives. 展开更多
关键词 soft X-ray MAGNETOPAUSE RECONNECTION low-pass filter LEXI SMILE
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SMILE soft X-ray Imager flight model CCD370 pre-flight device characterisation 被引量:1
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作者 S.Parsons D.J.Hall +4 位作者 O.Hetherington T.W.Buggey T.Arnold M.W.J.Hubbard A.Holland 《Earth and Planetary Physics》 EI CSCD 2024年第1期25-38,共14页
Throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their performance.In order to understand the changes of the CCD370s within the sof... Throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their performance.In order to understand the changes of the CCD370s within the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance level.Three CCDs have been characterised,the two flight devices and the flight spa re.This has been carried out at the Open University in a bespo ke cleanroom measure ment facility.The results show that there is a cluster of bright pixels in the flight spa re which increases in size with tempe rature.However at the nominal ope rating tempe rature(-120℃) it is within the procure ment specifications.Overall,the devices meet the specifications when ope rating at -120℃ in 6 × 6 binned frame transfer science mode.The se rial charge transfer inefficiency degrades with temperature in full frame mode.However any charge losses are recovered when binning/frame transfer is implemented. 展开更多
关键词 CCD soft X-ray imager characterisation SMILE
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Mechanism of high-preload support based on the NPR anchor cable in layered soft rock tunnels 被引量:1
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作者 SUI Qiru HE Manchao +3 位作者 SHI Mengfan TAO Zhigang ZHAO Feifei ZHANG Xiaoyu 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1403-1418,共16页
The control of large deformation problems in layered soft rock tunnels needs to solve urgently.The roof problem is particularly severe among the deformation issues in tunnels.This study first analyzes the asymmetric d... The control of large deformation problems in layered soft rock tunnels needs to solve urgently.The roof problem is particularly severe among the deformation issues in tunnels.This study first analyzes the asymmetric deformation modes in layered soft rock tunnels with large deformations.Subsequently,we construct a mechanical model under ideal conditions for controlling the roof of layered soft rock tunnels through high preload with the support of NPR anchor cables.The prominent roles of long and short NPR anchor cables in the support system are also analyzed.The results indicate the significance of high preload in controlling the roof of layered soft rock tunnels.The short NPR anchor cables effectively improve the integrity of the stratified soft rock layers,while the long NPR anchor cables effectively mobilize the self-bearing capacity of deep-stable rock layers.Finally,the high-preload support method with NPR anchor cables is validated to have a good effect on controlling large deformations in layered soft rock tunnels through field monitoring data. 展开更多
关键词 Tunnel engineering soft rock High-preload support NPR anchor cables
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Mechanical properties and acoustic emission characteristics of soft rock with different water contents under dynamic disturbance 被引量:1
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作者 Yujing Jiang Lugen Chen +4 位作者 Dong Wang Hengjie Luan Guangchao Zhang Ling Dong Bin Liang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期135-148,共14页
Uniaxial compression tests and cyclic loading acoustic emission tests were conducted on 20%,40%,60%,80%,dry and saturated muddy sandstone by using a creep impact loading system to investigate the mechanical properties... Uniaxial compression tests and cyclic loading acoustic emission tests were conducted on 20%,40%,60%,80%,dry and saturated muddy sandstone by using a creep impact loading system to investigate the mechanical properties and acoustic emission characteristics of soft rocks with different water contents under dynamic disturbance.The mechanical properties and acoustic emission characteristics of muddy sandstones at different water contents were analysed.Results of experimental studies show that water is a key factor in the mechanical properties of rocks,softening them,increasing their porosity,reducing their brittleness and increasing their plasticity.Under uniaxial compression,the macroscopic damage characteristics of the muddy sandstone change from mono-bevel shear damage and‘X’type conjugate bevel shear damage to a roadway bottom-drum type damage as the water content increases.Dynamic perturbation has a strengthening effect on the mechanical properties of samples with 60%and less water content,and a weakening effect on samples with 80%and more water content,but the weakening effect is not obvious.Macroscopic damage characteristics of dry samples remain unchanged,water samples from shear damage and tensile–shear composite damage gradually transformed into cleavage damage,until saturation transformation monoclinic shear damage.The evolution of acoustic emission energy and event number is mainly divided into four stages:loading stage(Ⅰ),dynamic loading stage(Ⅱ),yield failure stage(Ⅲ),and post-peak stage(Ⅳ),the acoustic emission characteristics of the stages were different for different water contents.The characteristic value of acoustic emission key point frequency gradually decreases,and the damage degree of the specimen increases,corresponding to low water content—high main frequency—low damage and high water content—low main frequency—high damage. 展开更多
关键词 Dynamic disturbance soft rock Cyclic loading Acoustic emission Water content
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Two methods for separating the magnetospheric solar wind charge exchange soft X-ray emission from the diffuse X-ray background 被引量:2
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作者 YingJie Zhang TianRan Sun +5 位作者 JenniferACarter WenHao Liu Steve Sembay ShuiNai Zhang Li Ji Chi Wang 《Earth and Planetary Physics》 EI CSCD 2024年第1期119-132,共14页
Solar wind charge exchange(SWCX)is the process of solar wind high-valence ions exchanging charges with neutral components and generating soft X-rays.Recently,detecting the SWCX emission from the magnetosphere is propo... Solar wind charge exchange(SWCX)is the process of solar wind high-valence ions exchanging charges with neutral components and generating soft X-rays.Recently,detecting the SWCX emission from the magnetosphere is proposed as a new technique to study the magnetosphere using panoramic soft X-ray imaging.To better prepare for the data analysis of upcoming magnetospheric soft X-ray imaging missions,this paper compares the magnetospheric SWCX emission obtained by two methods in an XMM-Newton observation,during which the solar wind changed dramatically.The two methods differ in the data used to fit the diffuse X-ray background(DXB)parameters in spectral analysis.The method adding data from the ROSAT All-Sky Survey(RASS)is called the RASS method.The method using the quiet observation data is called the Quiet method,where quiet observations usually refer to observations made by the same satellite with the same target but under weaker solar wind conditions.Results show that the spectral compositions of magnetospheric SWCX emission obtained by the two methods are very similar,and the changes in intensity over time are highly consistent,although the intensity obtained by the RASS method is about 2.68±0.56 keV cm^(-2)s^(-1)sr^(-1)higher than that obtained by the Quiet method.Since the DXB intensity obtained by the RASS method is about 2.84±0.74 keV cm^(-2)s^(-1)sr^(-1)lower than that obtained by the Quiet method,and the linear correlation coefficient between the difference of SWCX and DXB obtained by the two methods in diffe rent energy band is close to-1,the diffe rences in magnetospheric SWCX can be fully attributed to the diffe rences in the fitted DXB.The difference between the two methods is most significant when the energy is less than 0.7 keV,which is also the main energy band of SWCX emission.In addition,the difference between the two methods is not related to the SWCX intensity and,to some extent,to solar wind conditions,because SWCX intensity typically va ries with the solar wind.In summary,both methods are robust and reliable,and should be considered based on the best available options. 展开更多
关键词 solar wind charge exchange(SWCX) ROSAT All-Sky Survey(RASS) soft X-ray X-ray imaging MAGNETOSPHERE
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Hybrid-Vlasov simulation of soft X-ray emissions at the Earth’s dayside magnetospheric boundaries 被引量:2
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作者 M.Grandin H.K.Connor +5 位作者 S.Hoilijoki M.Battarbee Y.Pfau-Kempf U.Ganse K.Papadakis M.Palmroth 《Earth and Planetary Physics》 EI CSCD 2024年第1期70-88,共19页
Solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing tech... Solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing techniques.The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)and Lunar Environment heliospheric X-ray Imager(LEXI)missions aim to obtain soft Xray images of near-Earth space thanks to their Soft X-ray Imager(SXI)instruments.While earlier modeling works have already simulated soft X-ray images as might be obtained by SMILE SXI during its mission,the numerical models used so far are all based on the magnetohydrodynamics description of the space plasma.To investigate the possible signatures of ion-kinetic-scale processes in soft Xray images,we use for the first time a global hybrid-Vlasov simulation of the geospace from the Vlasiator model.The simulation is driven by fast and tenuous solar wind conditions and purely southward interplanetary magnetic field.We first produce global X-ray images of the dayside near-Earth space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial views.We then analyze regional features present in the images and show that they correspond to signatures in soft X-ray emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the magnetopause.Our results suggest that,although the time scales associated with the motion of those transient phenomena will likely be significantly smaller than the integration time of the SMILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in the soft X-ray images.For instance,a local increase by 30%in the proton density at the dayside magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray emissivity originating from this region.Likewise,a proton density increase by 14%in the magnetosheath associated with mirror-mode structures can result in an enhancement in the soft X-ray signal by 4%.These are likely conservative estimates,given that the solar wind conditions used in the Vlasiator run can be expected to generate weaker soft X-ray emissions than the more common denser solar wind.These results will contribute to the preparatory work for the SMILE and LEXI missions by providing the community with quantitative estimates of the effects of small-scale,transient phenomena occurring on the dayside. 展开更多
关键词 MAGNETOSPHERE MAGNETOSHEATH numerical simulation SMILE LEXI soft X-ray emissions hybrid-Vlasov model polar cusp flux transfer events mirror-mode waves
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Path Planning and Tracking Control for Parking via Soft Actor-Critic Under Non-Ideal Scenarios 被引量:1
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作者 Xiaolin Tang Yuyou Yang +3 位作者 Teng Liu Xianke Lin Kai Yang Shen Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期181-195,共15页
Parking in a small parking lot within limited space poses a difficult task. It often leads to deviations between the final parking posture and the target posture. These deviations can lead to partial occupancy of adja... Parking in a small parking lot within limited space poses a difficult task. It often leads to deviations between the final parking posture and the target posture. These deviations can lead to partial occupancy of adjacent parking lots, which poses a safety threat to vehicles parked in these parking lots. However, previous studies have not addressed this issue. In this paper, we aim to evaluate the impact of parking deviation of existing vehicles next to the target parking lot(PDEVNTPL) on the automatic ego vehicle(AEV) parking, in terms of safety, comfort, accuracy, and efficiency of parking. A segmented parking training framework(SPTF) based on soft actor-critic(SAC) is proposed to improve parking performance. In the proposed method, the SAC algorithm incorporates strategy entropy into the objective function, to enable the AEV to learn parking strategies based on a more comprehensive understanding of the environment. Additionally, the SPTF simplifies complex parking tasks to maintain the high performance of deep reinforcement learning(DRL). The experimental results reveal that the PDEVNTPL has a detrimental influence on the AEV parking in terms of safety, accuracy, and comfort, leading to reductions of more than 27%, 54%, and 26%respectively. However, the SAC-based SPTF effectively mitigates this impact, resulting in a considerable increase in the parking success rate from 71% to 93%. Furthermore, the heading angle deviation is significantly reduced from 2.25 degrees to 0.43degrees. 展开更多
关键词 Automatic parking control strategy parking deviation(APS) soft actor-critic(SAC)
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Direct 4D printing of functionally graded hydrogel networks for biodegradable,untethered,and multimorphic soft robots
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作者 Soo Young Cho Dong Hae Ho +1 位作者 Sae Byeok Jo Jeong Ho Cho 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期407-416,共10页
Recent advances in functionally graded additive manufacturing(FGAM)technology have enabled the seamless hybridization of multiple functionalities in a single structure.Soft robotics can become one of the largest benef... Recent advances in functionally graded additive manufacturing(FGAM)technology have enabled the seamless hybridization of multiple functionalities in a single structure.Soft robotics can become one of the largest beneficiaries of these advances,through the design of a facile four-dimensional(4D)FGAM process that can grant an intelligent stimuli-responsive mechanical functionality to the printed objects.Herein,we present a simple binder jetting approach for the 4D printing of functionally graded porous multi-materials(FGMM)by introducing rationally designed graded multiphase feeder beds.Compositionally graded cross-linking agents gradually form stable porous network structures within aqueous polymer particles,enabling programmable hygroscopic deformation without complex mechanical designs.Furthermore,a systematic bed design incorporating additional functional agents enables a multi-stimuli-responsive and untethered soft robot with stark stimulus selectivity.The biodegradability of the proposed 4D-printed soft robot further ensures the sustainability of our approach,with immediate degradation rates of 96.6%within 72 h.The proposed 4D printing concept for FGMMs can create new opportunities for intelligent and sustainable additive manufacturing in soft robotics. 展开更多
关键词 intelligent and sustainable additive manufacturing multi-material four-dimensional printing untethered soft robot multi-stimuli-responsive soft robot biodegradable soft robotics
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Simulation of the SMILE Soft X-ray Imager response to a southward interplanetary magnetic field turning 被引量:1
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作者 Andrey Samsonov Graziella Branduardi-Raymont +3 位作者 Steven Sembay Andrew Read David Sibeck Lutz Rastaetter 《Earth and Planetary Physics》 EI CSCD 2024年第1期39-46,共8页
The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)Soft X-ray Imager(SXI)will shine a spotlight on magnetopause dynamics during magnetic reconnection.We simulate an event with a southward interplanetary magne... The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)Soft X-ray Imager(SXI)will shine a spotlight on magnetopause dynamics during magnetic reconnection.We simulate an event with a southward interplanetary magnetic field turning and produce SXI count maps with a 5-minute integration time.By making assumptions about the magnetopause shape,we find the magnetopause standoff distance from the count maps and compare it with the one obtained directly from the magnetohydrodynamic(MHD)simulation.The root mean square deviations between the reconstructed and MHD standoff distances do not exceed 0.2 RE(Earth radius)and the maximal difference equals 0.24 RE during the 25-minute interval around the southward turning. 展开更多
关键词 MAGNETOPAUSE magnetic reconnection solar wind charge exchange southward interplanetary magnetic field numerical modeling Solar wind Magnetosphere Ionosphere Link Explorer(SMILE) soft X-ray Imager
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A Reputation-Based AODV Protocol for Blackhole and Malfunction Nodes Detection and Avoidance
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作者 Qussai M.Yaseen Monther Aldwairi Ahmad Manasrah 《Computers, Materials & Continua》 SCIE EI 2024年第8期1867-1888,共22页
Enhancing the security of Wireless Sensor Networks(WSNs)improves the usability of their applications.Therefore,finding solutions to various attacks,such as the blackhole attack,is crucial for the success of WSN applic... Enhancing the security of Wireless Sensor Networks(WSNs)improves the usability of their applications.Therefore,finding solutions to various attacks,such as the blackhole attack,is crucial for the success of WSN applications.This paper proposes an enhanced version of the AODV(Ad Hoc On-Demand Distance Vector)protocol capable of detecting blackholes and malfunctioning benign nodes in WSNs,thereby avoiding them when delivering packets.The proposed version employs a network-based reputation system to select the best and most secure path to a destination.To achieve this goal,the proposed version utilizes the Watchdogs/Pathrater mechanisms in AODV to gather and broadcast reputations to all network nodes to build the network-based reputation system.To minimize the network overhead of the proposed approach,the paper uses reputation aggregator nodes only for forwarding reputation tables.Moreover,to reduce the overhead of updating reputation tables,the paper proposes three mechanisms,which are the prompt broadcast,the regular broadcast,and the light broadcast approaches.The proposed enhanced version has been designed to perform effectively in dynamic environments such as mobile WSNs where nodes,including blackholes,move continuously,which is considered a challenge for other protocols.Using the proposed enhanced protocol,a node evaluates the security of different routes to a destination and can select the most secure routing path.The paper provides an algorithm that explains the proposed protocol in detail and demonstrates a case study that shows the operations of calculating and updating reputation values when nodes move across different zones.Furthermore,the paper discusses the proposed approach’s overhead analysis to prove the proposed enhancement’s correctness and applicability. 展开更多
关键词 AODV blackhole malfunction nodes pathrater reputation system wireless sensor networks(WSNs) watchdogs
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Malfunction Diagnosis of the GTCC System under All Operating Conditions Based on Exergy Analysis
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作者 Xinwei Wang Ming Li +2 位作者 Hankun Bing Dongxing Zhang Yuanshu Zhang 《Energy Engineering》 EI 2024年第12期3875-3898,共24页
After long-term operation,the performance of components in the GTCC system deteriorates and requires timely maintenance.Due to the inability to directly measure the degree of component malfunction,it is necessary to u... After long-term operation,the performance of components in the GTCC system deteriorates and requires timely maintenance.Due to the inability to directly measure the degree of component malfunction,it is necessary to use advanced exergy analysis diagnosis methods to characterize the components’health condition(degree of malfunction)through operation data of the GTCC system.The dissipative temperature is used to describe the degree of malfunction of different components in the GTCC system,and an advanced exergy analysis diagnostic method is used to establish a database of overall operating condition component malfunctions in theGTCC system.Ebsilon software is used to simulate the critical parameters of the malfunctions of the GTCC system components and to obtain the changes in the dissipative temperature of different components.Meanwhile,the fuel consumption and economic changes of the GTCC system on a characteristic power supply day under health and malfunction conditions are analyzed.Finally,the effects of maintenance costs,electricity,and gas prices on maintenance expenses and profits are analyzed.The results show that the GTCC system maintenance profit is 6.07$/MWh,while the GTCC system maintenance expense is 5.83$/MWh.Compared with the planned maintenancemode,the malfunction maintenance mode saves 0.24$/MWh.Simultaneously,the maintenance coefficient of GTCC should be adjusted under different malfunctions to obtain a more accurate maintenance period. 展开更多
关键词 Gas turbine combined cycle malfunction diagnosis exergy analysis maintenance profits
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An Automatic Implementation of Oropharyngeal Swab Sampling for Diagnosing Respiratory Infectious Diseases via Soft Robotic End-Effectors
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作者 Yafeng Cui Wenjie Yu +8 位作者 Jingjing Li Qi Shao Ding Weng Guoping Yin Xiaohao Zhang Xinjun Liu Jingying Ye Jiadao Wang Huichan Zhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期55-67,共13页
The most widely adopted method for diagnosing respiratory infectious diseases is to conduct polymerase chain reaction(PCR)assays on patients’respiratory specimens,which are collected through either nasal or oropharyn... The most widely adopted method for diagnosing respiratory infectious diseases is to conduct polymerase chain reaction(PCR)assays on patients’respiratory specimens,which are collected through either nasal or oropharyngeal swabs.The manual swab sampling process poses a high risk to the examiner and may cause false-negative results owing to improper sampling.In this paper,we propose a pneumatically actuated soft end-effector specifically designed to achieve all of the tasks involved in swab sampling.The soft end-effector utilizes circumferential instability to ensure grasping stability,and exhibits several key properties,including high load-to-weight ratio,error tolerance,and variable swab-tip stiffness,leading to successful automatic robotic oropharyngeal swab sampling,from loosening and tightening the transport medium tube cap,holding the swab,and conducting sampling,to snapping off the swab tail and sterilizing itself.Using an industrial collaborative robotic arm,we integrated the soft end-effector,force sensor,camera,lights,and remote-control stick,and developed a robotic oropharyngeal swab sampling system.Using this swab sampling system,we conducted oropharyngeal swab-sampling tests on 20 volunteers.Our Digital PCR assay results(RNase P RNA gene absolute copy numbers for the samples)revealed that our system successfully collected sufficient numbers of cells from the pharyngeal wall for respiratory disease diagnosis.In summary,we have developed a pharyngeal swab-sampling system based on an“enveloping”soft actuator,studied the sampling process,and imple-mented whole-process robotic oropharyngeal swab-sampling. 展开更多
关键词 Diagnosis Medical robot soft end-effector Swab-sampling Digital PCR
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A Review on Soft Ionic Touch Point Sensors
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作者 Gibeom Lee Donghyun Lee +1 位作者 Gwang-Bum Im Younghoon Lee 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第6期193-208,共16页
A touch sensor is an essential component in meeting the growing demand for human-machine interfaces.These sensors have been developed in wearable,attachable,and even implantable forms to acquire a wide range of inform... A touch sensor is an essential component in meeting the growing demand for human-machine interfaces.These sensors have been developed in wearable,attachable,and even implantable forms to acquire a wide range of information from humans.To be applied to the human body,sensors are required to be biocompatible and not restrict the natural movement of the body.Ionic materials are a promising candidate for soft touch sensors due to their outstanding properties,which include high stretchability,transparency,ionic conductivity,and biocompatibility.Here,this review discusses the unique features of soft ionic touch point sensors,focusing on the ionic material and its key role in the sensor.The touch sensing mechanisms include piezocapacitive,piezoresistive,surface capacitive,piezoelectric,and triboelectric and triboresistive sensing.This review analyzes the implementation hurdles and future research directions of the soft ionic touch sensors for their transformative potential. 展开更多
关键词 iontronics ionic materials soft materials touch sensors
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Estimating the yield stress of soft materials via laser-induced breakdown spectroscopy
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作者 龚书航 李亚举 +7 位作者 钱东斌 叶晋瑞 赵扣 曾强 陈良文 张少锋 杨磊 马新文 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期428-432,共5页
Taking three typical soft samples prepared respectively by loose packings of 77-,95-,and 109-μm copper grains as examples,we perform an experiment to investigate the energy-dependent laser-induced breakdown spectrosc... Taking three typical soft samples prepared respectively by loose packings of 77-,95-,and 109-μm copper grains as examples,we perform an experiment to investigate the energy-dependent laser-induced breakdown spectroscopy(LIBS)of soft materials.We discovered a reversal phenomenon in the trend of energy dependence of plasma emission intensity:increasing initially and then decreasing separated by a well-defined critical energy.The trend reversal is attributed to the laser-induced recoil pressure at the critical energy just matching the sample's yield strength.As a result,a one-to-one correspondence can be well established between the samples'yield stress and the critical energy that is easily obtainable from LIBS measurements.This allows us to propose an innovative method for estimating the yield stress of soft materials via LIBS with attractive advantages including in-situ remote detection,real-time data collection,and minimal destructive to sample. 展开更多
关键词 laser-induced breakdown spectroscopy soft materials yield stress
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MHz cut-off frequency and permeability mechanism of iron-based soft magnetic composites
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作者 Xiao-Wei Jin Tong Li +1 位作者 Hui-Gang Shi De-Sheng Xue 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期560-564,共5页
The lack of soft magnetic composites with high power density in MHz frequency range has become an obstacle in the efficient operation of the electrical and electronic equipments.Here,a promising method to increase the... The lack of soft magnetic composites with high power density in MHz frequency range has become an obstacle in the efficient operation of the electrical and electronic equipments.Here,a promising method to increase the cut-off frequency of iron-based soft magnetic composites to hundreds of MHz is reported.The cut-off frequency is increased from 10 MHz to 1 GHz by modulating the height of the ring,the distribution of particles,and the particle size.The mechanism of cut-off frequency and permeability is the coherent rotation of domain modulated by inhomogeneous field due to the eddy current effect.An empirical formula for the cut-off frequency in a magnetic ring composed of iron-based particles is established from experimental data.This work provides an effective approach to fabricate soft magnetic composites with a cut-off frequency in hundreds of MHz. 展开更多
关键词 cut-off frequency PERMEABILITY eddy current effect soft magnetic composites
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MXenes for Bioinspired Soft Actuators:Advancements in Angle-Independent Structural Colors and Beyond
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作者 Siavash Iravani Rajender S.Varma 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期18-34,共17页
Soft actuators have garnered substantial attention in current years in view of their potential appliances in diverse domains like robotics,biomedical devices,and biomimetic systems.These actuators mimic the natural mo... Soft actuators have garnered substantial attention in current years in view of their potential appliances in diverse domains like robotics,biomedical devices,and biomimetic systems.These actuators mimic the natural movements of living organisms,aiming to attain enhanced flexibility,adaptability,and versatility.On the other hand,angle-independent structural color has been achieved through innovative design strategies and engineering approaches.By carefully controlling the size,shape,and arrangement of nanostructures,researchers have been able to create materials exhibiting consistent colors regardless of the viewing angle.One promising class of materials that holds great potential for bioinspired soft actuators is MXenes in view of their exceptional mechanical,electrical,and optical properties.The integration of MXenes for bioinspired soft actuators with angle-independent structural color offers exciting possibilities.Overcoming material compatibility issues,improving color reproducibility,scalability,durability,power supply efficiency,and cost-effectiveness will play vital roles in advancing these technologies.This perspective appraises the development of bioinspired MXene-centered soft actuators with angleindependent structural color in soft robotics. 展开更多
关键词 MXenes MXene-based composites Bioinspired soft robotics Angle-independent structural color
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Applications of Soft Computing Methods in Backbreak Assessment in Surface Mines: A Comprehensive Review
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作者 Mojtaba Yari Manoj Khandelwal +3 位作者 Payam Abbasi Evangelos I.Koutras Danial Jahed Armaghani Panagiotis G.Asteris 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2207-2238,共32页
Geo-engineering problems are known for their complexity and high uncertainty levels,requiring precise defini-tions,past experiences,logical reasoning,mathematical analysis,and practical insight to address them effecti... Geo-engineering problems are known for their complexity and high uncertainty levels,requiring precise defini-tions,past experiences,logical reasoning,mathematical analysis,and practical insight to address them effectively.Soft Computing(SC)methods have gained popularity in engineering disciplines such as mining and civil engineering due to computer hardware and machine learning advancements.Unlike traditional hard computing approaches,SC models use soft values and fuzzy sets to navigate uncertain environments.This study focuses on the application of SC methods to predict backbreak,a common issue in blasting operations within mining and civil projects.Backbreak,which refers to the unintended fracturing of rock beyond the desired blast perimeter,can significantly impact project timelines and costs.This study aims to explore how SC methods can be effectively employed to anticipate and mitigate the undesirable consequences of blasting operations,specifically focusing on backbreak prediction.The research explores the complexities of backbreak prediction and highlights the potential benefits of utilizing SC methods to address this challenging issue in geo-engineering projects. 展开更多
关键词 Backbreak BLASTING soft computing methods prediction theory-guided machine learning
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A rechargeable coating with temporal-sequence antibacterial activity and soft tissue sealing
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作者 Fang Wang Shiwei Guan +3 位作者 Min Xing Wenhao Qian Jiajun Qiu Xuanyong Liu 《Bioactive Materials》 SCIE CSCD 2024年第9期224-238,共15页
Transcutaneous implants that penetrate through skin or mucosa are susceptible to bacteria invasion and lack proper soft tissue sealing.Traditional antibacterial strategies primarily focus on bacterial eradication,but ... Transcutaneous implants that penetrate through skin or mucosa are susceptible to bacteria invasion and lack proper soft tissue sealing.Traditional antibacterial strategies primarily focus on bacterial eradication,but excessive exposure to bactericidal agents can induce noticeable tissue damage.Herein,a rechargeable model(HPI-Ti)was constructed using perylene polyimide,an aqueous battery material,achieving temporal-sequence regulation of bacterial killing and soft tissue sealing.Charge storage within HPI-Ti is achieved after galvanostatic charge,and chemical discharge is initiated when immersed in physiological environments.During the early discharge stage,post-charging HPI-Ti demonstrates an antibacterial rate of 99.96±0.01%for 24 h,preventing biofilm formation.Contact-dependent violent electron transfer between bacteria and the material causes bacteria death.In the later discharge stage,the attenuated discharging status creates a gentler electron-transfer microenvironment for fibroblast proliferation.After discharge,the antibacterial activity can be reinstated by recharge against potential reinfection.The antibacterial efficacy and soft tissue compatibility were verified in vivo.These results demonstrate the potential of the charge-transfer-based model in reconciling antibacterial efficacy with tissue compatibility. 展开更多
关键词 Polyimides Medical titanium Transcutaneous implants ANTIBACTERIAL soft tissue sealing
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