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Assessment of SoilGrids data for soil erosion estimation at watershed scale: A case study in northern Thailand

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Pedosphere 2024年第4期34卷 797-813页

作者： Chike Onyeka MADUEKE Dhruba Pikha SHRESTHA Panagiotis NYKTAS Department of Natural Resources Faculty of Geo-information Science and Earth Observation(ITC)University of TwenteEnschede 7500 AEthe Netherlands Department of Applied Earth Sciences Faculty of Geo-information Science and Earth Observation(ITC)University of TwenteEnschede 7500 AEthe Netherlands Department of Soil Science and Land Resources Management Nnamdi Azikiwe UniversityP.M.B.5025AwkaAnambra State 420110Nigeria

Soil erosion has been identified as one of the most destructive forms of land degradation,posing a threat to the sustainability of global economic,social and environmental *** underscores the need for sustainable land management that takes erosion control and prevention into *** requires the use of state-of-the-art erosion prediction *** models often require extensive input of detailed spatial and temporal data,some of which are not readily available in many developing countries,particularly detailed soil *** soil dataset Global Gridded Soil Information(SoilGrids)could potentially fill the data ***,its value and accuracy for soil erosion modelling in the humid tropics is still unknown,necessitating the need to assess its value vis-à-vis field-based *** major objective of this study was to conduct a comparative assessment of the value of SoilGrids and field-based soil data for estimating soil *** samples were collected from five physiographic positions(summit,shoulder,back slope,foot slope,and toe slope)using the soil catena *** were collected using a 5-cm steel sample ring(undisturbed)and a spade(disturbed).Data of the landform,predominant vegetation types,canopy cover,average plant height,land use,soil depth,shear strength,and soil color were recorded for each *** soil samples were subjected to laboratory analysis for saturated hydraulic conductivity,bulk density,particle size distribution,and organic matter *** functions were applied on the SoilGrids and field-based data to generate soil hydrological *** resultant field-based data were compared with the SoilGrids data for corresponding points/areas to determine the potential similarities of the two *** datasets were then used as inputs for soil erosion assessment using the revised Morgan-Morgan-Finney *** results from both datasets were again compared to determine the degree of *** r

关键词： hillslope modelling pedotransfer function similarity assessment soil erosion modelling soil loss soil survey

Towards a lightweight security framework using blockchain and machine learning

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BLOCKCHAIN-RESEARCH AND APPLICATIONS 2024年第1期5卷 107-118页

作者： Ismail, Shereen Nouman, Muhammad Dawoud, Diana W. Reza, Hassan Univ North Dakota Sch Elect Engn & Comp Sci Grand Forks ND 58202 USA COMSATS Univ Islamabad Dept Comp Sci Islamabad 44000 Pakistan Univ Dubai Coll Engn & Informat Technol Dubai U Arab Emirates

Cyber-attacks pose a significant challenge to the security of Internet of Things (IoT) sensor networks, necessitating the development of robust countermeasures tailored to their unique characteristics and limitations. Various prevention and detection techniques have been proposed to mitigate these attacks. In this paper, we propose an integrated security framework using blockchain and Machine Learning (ML) to protect IoT sensor networks. The framework consists of two modules: a blockchain prevention module and an ML detection module. The blockchain prevention module has two lightweight mechanisms: identity management and trust management. Identity management employs a lightweight Smart Contract (SC) to manage node registration and authentication, ensuring that unauthorized entities are prohibited from engaging in any tasks, while trust management uses a lightweight SC that is responsible for maintaining trust and credibility between sensor nodes throughout the network's lifetime and tracking historical node behaviors. Consensus and transaction validation are achieved through a Verifiable Byzantine Fault Tolerance (VBFT) mechanism to ensure network reliability and integrity. The ML detection module utilizes the Light Gradient Boosting Machine (LightGBM) algorithm to classify malicious nodes and notify the blockchain network if it must make decisions to mitigate their impacts. We investigate the performance of several off -the -shelf ML algorithms, including Logistic Regression, Complement Naive Bayes, Nearest Centroid, and Stacking, using the WSN-DS dataset. LightGBM is selected following a detailed comparative analysis conducted using accuracy, precision, recall, F1 -score, processing time, training time, prediction time, computational complexity, and Matthews Correlation Coefficient (MCC) evaluation metrics.

关键词： Blockchain Machine learning IoT Security Integration Smart contracts

Long-term Integration Ability of the Submillimeter Wave Astronomy Satellite(SWAS)Spectral Line Receivers

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Research in Astronomy and Astrophysics 2024年第6期24卷 315-322页

作者： Bing-Ru Wang Di Li Paul F.Goldsmith Jingwen Wu Chao-Wei Tsai Rudolf Schieder Gary J.Melnick national Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Research Center for Astronomical Computing Zhejiang LaboratoryHangzhou 311100China Jet Propulsion Laboratory California Institute of TechnologyPasadenaCA 91109USA Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China KOSMA I.Physik.InstitutUniversität zu KölnZülpicher Str.7750937 KölnGermany Center for Astrophysics|Harvard&Smithsonian 60 Garden StreetMS 66CambridgeMA 02138USA

The Submillimeter Wave Astronomy Satellite(SWAS)was the first space telescope capable of high spectral resolution observations of terahertz spectral *** have investigated the integration ability of its two receivers and spectrometer during five and a half years of on-orbit *** CI,O_(2),H_(2)O,and^(13)CO spectra taken toward all observed Galactic sources were *** present results are based on spectra with a total integration time of up to 2.72×10~4hr(■10~8s).The noise in the spectra is generally consistent with that expected from the radiometer equation,without any sign of approaching a noise *** noise performance reflects the extremely stable performance of the passively cooled front end as well as other relevant components in the SWAS instrument throughout its mission lifetime.

关键词： telescopes space vehicles:instruments instrumentation:miscellaneous ISM:lines and bands

The Soft X-ray Imager(SXI)on the SMILE Mission

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Earth and Planetary Physics 2024年第1期8卷 5-14页

作者： S.Sembay A.L.Alme 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 School of Physics and Astronomy University of LeicesterLeicesterLE17RHUK space Park Leicester University of LeicesterLeicesterLE17RHUK Mullard space Science Laboratory University College LondonDorkingRH56NTUK Centre for Electronic Imaging Open UniversityMilton KeynesMK76 AAUK Birkeland Centre for space Science Department of Physics and TechnologyUniv.of BergenN-5007 BergenNorway University of Vienna A-1010 ViennaAustria space Research Institute Austrian Academy of SciencesA-8042 GrazAustria national Institute of Aerospace Technology MadridSpain ESTEC European Space Agency2201 AZ NoordwijkNetherlands State Key Laboratory of space Weather National Space Science CentreBeijing 100190China University of Applied Sciences and Arts Northwestern Switzerland CH-5210 WindischSwitzerland Koegl space GmbH CH-8157 DielsdorfSwitzerland space Acoustics GmbH CH-8157 DielsdorfSwitzerland Zurich University of Applied Sciences 8400 WinterhurSwitzerland Genov Solutions N-5172 LoddefjordNorway STM Engineering N-5165 LaksevagNorway John Hopkins University Applied Physics Laboratory MD 20723USA nasa/Goddard space Flight Centre MD 20771USA Center for space Physics Boston UniversityBostonMA 02215USA Department of Theoretical Physics and Astrophysics Masaryk University60177 BrnoCzech Republic Institute of Physics E¨otvo¨s Lor´and University1053 BudapestHungary Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100045China Centro de Astrobiologia(CAB) CSIC-INTAMadridSpain

The Soft X-ray Imager(SXI)is part of the scientific payload of the Solar wind Magnetosphere Ionosphere Link Explorer(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 *** 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 *** 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 *** 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 *** 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 *** 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.

关键词： Soft X-ray Imaging micropore optics large area CCD

On the longitudinal shifts of the Agulhas retroflection point

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Acta Oceanologica Sinica 2024年第5期43卷 16-29页

作者： Weiwei Zhang Xiaoyi Yang Wei Zhuang Xiaohai Yan State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen 361002China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China Center for Remote Sensing College of EarthOcean and EnvironmentUniversity of DelawareNewarkDE 19716USA Joint Center for Remote Sensing University of Delaware-Xiamen UniversityNewarkDE 19716USA and Xiamen 361002China

The Agulhas system is the strongest western boundary current system in the Southern Hemisphere and plays an important role in modulating the Indian-to-Atlantic Ocean water exchange by the Agulhas *** is difficult to measure in situ transport of the Agulhas leakage as well as the Agulhas retroflection position due to their intermittent *** this study,an innovative kinematic algorithm was designed and applied to the gridded altimeter observational data,to ascertain the longitudinal position of Agulhas retroflection,the stability of Agulhas jet stream,as well as its *** results show that the east-west shift of retroflection is related neither to the strength of Agulhas current nor to its *** analysis uncovers the connection between the westward extension of Agulhas jet stream and an anomalous cyclonic circulation at its northern side,which is likely attributed to the local wind stress curl *** confirm the effect of local wind forcing on the east-west shift of retroflection,numerical sensitivity experiments were *** results show that the local wind stress can induce a similar longitudinal shift of the retroflection as altimetry *** statistical and case study indicates that whether an Agulhas ring can continuously migrate westward to the Atlantic Ocean or re-merge into the main flow depends on the retroflection ***,the westward retroflection may contribute to a stronger Agulhas leakage than the eastward retroflection.

关键词： Agulhas system Agulhas leakage retroflection position local wind stress curl

Single-point and Filtered Relative Position Estimation for Visual Docking

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Computer Modeling in Engineering & Sciences 2016年第2期111卷 147-169页

作者： Dylan Conway Daniele Mortari Aerospace Engineering Texas A&M UniversityCollege Station77843

This paper presents a new method to estimate position from line-ofsight measurements to known targets when attitude is *** algorithm has two *** first produces a closed-form unbiased estimate for position that does not account for the measurement error *** second stage is iterative and produces an estimate of position that explicitly accounts for the measurement error covariance and the coupling between measurement error and sensor-to-target *** algorithm gives an accurate estimate of both position and the corresponding position error covariance and has a low computational *** computational complexity is O(n)for n point-targets and only a 3×3 linear system must be *** algorithm is demonstrated for single-point position estimation to verify the accuracy of the resulting position and *** improvements over current methods are shown through statistical *** algorithm is then demonstrated in the context of sequential filtering for space vehicle docking.

关键词： Visual point algorithm

The mathematical weighting of GNSS observations based on different types of receivers/antennas and environmental conditions

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Geodesy and Geodynamics 2023年第5期14卷 521-540页

作者： Kamal Parvazi Saeed Farzaneh Abdolreza Safari School of Surveying and Geospatial Engineering College of EngineeringUniversity of TehranNorth Kargar Street***TehranIran

Stochastic models play an important role in achieving high accuracy in positioning,the ideal estimator in the least-squares(LS)can be obtained only by using the suitable stochastic *** study investigates the role of variance component estimation(VCE)in the LS method for Precise Point Positioning(PPP).This estimation is performed by considering the ionospheric-free(IF)functional model for code and the phase observation of Global Positioning System(GPS).The strategy for estimating the accuracy of these observations was evaluated to check the effect of the stochastic model in four modes:a)antenna type,b)receiver type,c)the tropospheric effect,and d)the ionosphere *** results show that using empirical variance for code and phase observations in some cases caused erroneous estimation of unknown components in the PPP *** is because a constant empirical variance may not be suitable for various receivers and antennas under different *** were compared in two cases using the stochastic model of nominal weight and weight estimated by *** position error difference for the east-west,north-south,and height components was 1.5 cm,4 mm,and 1.8 cm,***,weight estimation with LS-VCE can provide more appropriate ***,the convergence time based on four elevation-dependent models was evaluated using nominal weight and LS-VCE *** to the results,the LS-VCE has a higher convergence rate than the nominal *** weight estimation using LS-VCE improves the convergence time in four elevation-dependent models by 11,13,12,and 9 min,respectively.

关键词： Stochastic model Global positioning system Variance component estimation Least-squares Precise point positioning Elevation-dependent model

Quantitative analysis of morphometry on Ribb and Gumara watersheds: Implications for soil and water conservation

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International Soil and Water Conservation Research 2019年第2期7卷 150-157页

作者： Daniel Asfaw Getachew Workineh Debre Tabor University Department of Geography and Environmental Studies Ethiopia Debre Tabor University Department of Geography and Environmental Studies Ethiopia

Morphometric analysis is a quantitative measurement and mathematical analysis of *** plays a significant role in understanding the geohydrological characteristics of a drainage basin in relation to the terrain feature and its flow *** also helps to estimate the incidence of infiltration and runoff,and other related hydrological character of a watershed like erosion and sediment transport which has a strong implication for natural resource *** study has attempted to quantify the morphometric characteristics of Guna-Tana watershed for proper implementation of soil and water conservation *** (DEM) was used for extracting morphometric *** watershed covers a total area of 3601.5 km2 and it has a basin length of 78.89 *** has been tried to generate morphometric parameters which account basin drainage network,geometry,drainage texture,and relief characteristics together with hypsometric *** morphometric analysis of drainage density of the study watershed is 0.49 km/km2 which indicates the basin is highly permeable and result with better underground water storage *** number is 0.02 that implies the area is less prone to soil *** addition,it has stream frequency of 0.32 and form factor 0.57 which indicates slightly elongated basin *** analysis of its sub watersheds Gumara and Ribb was also ***,practicing soil and water conservation in the watershed could enhance/strengthen the water storage capacity,prevent sediment loss and related natural resource from the watershed that rehabilitate its productivity.

关键词： Morphometric analysis Drainage density Guna-Tana watershed Soil and water conservation

Construction and Optimization of TRNG Based Substitution Boxes for Block Encryption Algorithms

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Computers, Materials & Continua 2022年第11期73卷 2679-2696页

作者： Muhammad Fahad Khan Khalid Saleem Mohammed Alotaibi Mohammad Mazyad Hazzazi Eid Rehman Aaqif Afzaal Abbasi Muhammad Asif Gondal Quaid e Azam University Islamabad45320Pakistan Foundation University Islamabad Islamabad44000Pakistan College of Business administration University of TabukTabuk71491Saudi Arabia Department of Mathematics College of ScienceKing Khalid UniversityAbha61413Saudi Arabia Department of Mathematics and Sciences Dhofar UniversitySalalah211Oman

Internet of Things is an ecosystem of interconnected devices that are accessible through the *** recent research focuses on adding more smartness and intelligence to these edge *** makes them susceptible to various kinds of security *** edge devices rely on cryptographic techniques to encrypt the pre-processed data collected from the sensors deployed in the *** this regard,block cipher has been one of the most reliable options through which data security is *** strength of block encryption algorithms against different attacks is dependent on its nonlinear primitive which is called Substitution *** the design of S-boxes mainly algebraic and chaos-based techniques are used but researchers also found various weaknesses in these *** the other side,literature endorse the true random numbers for information security due to the reason that,true random numbers are purely *** this paper firstly a natural dynamical phenomenon is utilized for the generation of true random numbers based ***,a systematic literature review was conducted to know which metaheuristic optimization technique is highly adopted in the current decade for the optimization of *** on the outcome of Systematic Literature Review(SLR),genetic algorithm is chosen for the optimization of *** results of our method validate that the proposed dynamic S-boxes are effective for the block ***,our results showed that the proposed substitution boxes achieve better cryptographic strength as compared with state-of-the-art techniques.

关键词： IoT security sensors data encryption substitution box generation True Random Number Generators(TRNG) heuristic optimization genetic algorithm