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LUAR:Lightweight and Universal Attribute Revocation Mechanism with SGX Assistance towards Applicable ABE Systems
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作者 Fei Tang Ping Wang +3 位作者 Jiang Yu Huihui Zhu Mengxue Qin Ling Yang 《Computers, Materials & Continua》 2026年第3期1628-1646,共19页
Attribute-Based Encryption(ABE)has emerged as a fundamental access control mechanism in data sharing,enabling data owners to define flexible access policies.A critical aspect of ABE is key revocation,which plays a piv... Attribute-Based Encryption(ABE)has emerged as a fundamental access control mechanism in data sharing,enabling data owners to define flexible access policies.A critical aspect of ABE is key revocation,which plays a pivotal role in maintaining security.However,existing key revocation mechanisms face two major challenges:(1)High overhead due to ciphertext and key updates,primarily stemming from the reliance on revocation lists during attribute revocation,which increases computation and communication costs.(2)Limited universality,as many attribute revocation mechanisms are tailored to specific ABE constructions,restricting their broader applicability.To address these challenges,we propose LUAR(Lightweight and Universal Attribute Revocation),a novel revocation mechanism that leverages Intel Software Guard Extensions(SGX)while minimizing its inherent limitations.Given SGX’s constrained memory(≈90 MB in a personal computer)and susceptibility to side-channel attacks,we carefully manage its usage to reduce reliance while mitigating potential collusion risks between cloud service providers and users.To evaluate LUAR’s lightweight and universality,we integrate it with the classic BSW07 scheme,which can be seamlessly replaced with other ABE constructions.Experimental results demonstrate that LUAR enables secure attribute revocation with low computation and communication overhead.The processing time within the SGX environment remains stable at approximately 55 ms,regardless of the complexity of access policies,ensuring no additional storage or computational burden on SGX.Compared to the Hardware-based Revocable Attribute-Based Encryption(HR-ABE)scheme(IEEE S&P 2024),LUAR incurs a slightly higher computational cost within SGX;however,the overall time from initiating a data request to obtaining plaintext is shorter.As access policies grow more complex,LUAR’s advantages become increasingly evident,showcasing its superior efficiency and broader applicability. 展开更多
关键词 Attribute-based encryption attribute revocation LIGHTWEIGHT UNIVERSALITY
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A New Growth Model of Fault Attributes in a Strike-Slip Fault System in the Tarim Basin 被引量:4
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作者 ZHANG Yintao WU Guanghui +3 位作者 WANG Junfang LI Guohui WAN Xiaoguo YANG Tianyi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第5期1373-1380,共8页
Fault attributes generally display a consistent power–law-scaling relationship.Based on new 3 D seismic data,however,we found some exceptional fault attribute relationships of lengths(L)–throw(T)(vertical component ... Fault attributes generally display a consistent power–law-scaling relationship.Based on new 3 D seismic data,however,we found some exceptional fault attribute relationships of lengths(L)–throw(T)(vertical component of displacement),overlap zone length(Lo)–width(Wo)from a strike-slip fault system of the Ordovician carbonates in the Tarim Basin.The L–T relationship shows two linear segments with breakup at^40 km in fault length.This presents an exceptional throw increase in the second stage,which is attributed to a localization of vertical displacement and deformation in overlapping zones other than the different fault scales in a mature fault zone.The Lo–Wo relationship in the overlapping zones shows multiply stepped-shape patterns,suggesting multiple fault differential growth and periodic increase in fault size.Therefore,we propose a new alternative growth model of fault attributes in strike-slip fault zones,in which the overlapping zones accumulated localized displacement and deformation in the intracratonic strike-slip fault zone. 展开更多
关键词 fault modeling fault attributes strike-slip fault overlapping zone power-law-scaling fault growth process
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Attributes reduct and decision rules optimization based on maximal tolerance classification in incomplete information systems with fuzzy decisions 被引量:1
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作者 Fang Yang Yanyong Guan +1 位作者 Shujin Li Lei Du 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期995-999,共5页
A new approach to knowledge acquisition in incomplete information system with fuzzy decisions is proposed. In such incomplete information system, the universe of discourse is classified by the maximal tolerance classe... A new approach to knowledge acquisition in incomplete information system with fuzzy decisions is proposed. In such incomplete information system, the universe of discourse is classified by the maximal tolerance classes, and fuzzy approximations are defined based on them. Three types of relative reducts of maximal tolerance classes are then proposed, and three types of fuzzy decision rules based on the proposed attribute description are defined. The judgment theorems and approximation discernibility functions with respect to them are presented to compute the relative reduct by using Boolean reasoning techniques, from which we can derive optimal fuzzy decision rules from the systems. At last, three types of relative reducts of the system and their computing methods are given. 展开更多
关键词 rough sets information systems maximal tolerance class attribute reduct decision rules.
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Extending attributes page:a scheme for enhancing the reliability of storage system metadata
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作者 Juan WANG Dan FENG +1 位作者 Fang WANG Cheng-tao LU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第8期1106-1113,共8页
In an object-based storage system,a novel scheme named EAP(extending attributes page) is presented to enhance the metadata reliability of the system by adding the user object file information attributes page for each ... In an object-based storage system,a novel scheme named EAP(extending attributes page) is presented to enhance the metadata reliability of the system by adding the user object file information attributes page for each user object and storing the file-related attributes of each user object in object-based storage devices.The EAP scheme requires no additional hardware equipments compared to a general method which uses backup metadata servers to improve the metadata reliability.Leveraging a Markov chain,this paper compares the metadata reliability of the system using the EAP scheme with that using only metadata servers to offer the file metadata service.Our results demonstrate that the EAP scheme can dramatically enhance the reliability of storage system metadata. 展开更多
关键词 Metadata server Metadata reliability Markov model Extending attributes page (EAP)
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Sensing Attributes of an Agile Information System
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作者 Pankaj Pankaj Micki Hyde Arkalgud Ramaprasad 《Intelligent Information Management》 2013年第5期150-161,共12页
Information Systems (IS) agility is a current topic of interest in the IS industry. The study follows up on the work on the definition of the construct of IS agility which is defined as the ability of IS to sense a ch... Information Systems (IS) agility is a current topic of interest in the IS industry. The study follows up on the work on the definition of the construct of IS agility which is defined as the ability of IS to sense a change in real time;diagnose it in real time;and select and execute an action in real time. It explores the attributes for sensing in an Agile Information System. A set of attributes was initially derived using the practitioner literature and then refined using interviews with practitioners. Their importance and validity were established using a survey of the industry. All attributes derived from this study were deemed pertinent for sensing in an agile information system. Dimensions underlying these attributes were identified using Exploratory Factor Analysis. This list of attributes can form the basis for assessing and establishing sensing mechanisms to increase IS agility. 展开更多
关键词 INFORMATION systemS AGILITY AGILE INFORMATION systemS SENSING SENSING attributes
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Spatial Variability of Selected Soil Attributes under Agricultural Land Use System in a Mountainous Watershed, Ethiopia
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作者 Hailu Kendie Addis Andreas Klik Stefan Strohmeier 《International Journal of Geosciences》 2015年第6期605-613,共9页
In the Ethiopian Highlands, research projects were often measuring soil attributes of spatially structured point data but soil variability at a watershed scale is not clearly defined. This study was conducted to asses... In the Ethiopian Highlands, research projects were often measuring soil attributes of spatially structured point data but soil variability at a watershed scale is not clearly defined. This study was conducted to assess the correlation among selected soil attributes and to illustrate the spatial pattern and dependence of neighboring observations. The 53.7 km2?study watershed was divided into a 500 m by 500 m square grid using arcgis and at the center of each grid soil samples from 0 to 25 cm depth were collected within 184 locations. The descriptive statistics revealed available phosphorous (AP) had the largest coefficient of variation (CV = 104) while pH was the least variable. There was a positive link between elevation and SOC whereas bulk density (ρd) and pH indicated an inverse relationship with elevation and SOC. The value for nugget/sill of ρd, pH and elevation are less than 0.25, and depicts that it has strong spatial autocorrelation. The value for nugget/?sill of SOC, and TN found between 0.25 and 0.75, and indicate that they have moderate spatial?autocorrelation. With regard to AP, the value for nugget/sill is more than 0.75, which displays a weak?spatial autocorrelation. Semivariograms of ρd, pH and elevation were best fitted to Gaussian model whereas SOC, TN and AP were best fitted to exponential function. Generally, the study verified that soil measurements taken at the given scale through regular sampling interval were adequate to capture the spatial dependence of numerous initial soil assessments in the study watershed. 展开更多
关键词 SEMIVARIOGRAM Soil ATTRIBUTE Spatial VARIABILITY WATERSHED
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Habitat fragmentation differentially affects invasive and native plant diversity in a human-dominated wetland island system
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作者 Jinliang Liu Mengyuan Chen +4 位作者 Lu Wang Tengteng Liu Xinjie Jin Fei-Hai Yu Yonghua Zhang 《Plant Diversity》 2025年第5期824-832,共9页
Managing invasive species requires identifying the factors that determine alien species invasion success.This study investigates how anthropogenic and biogeographical factors influence alien plant invasion in the Sany... Managing invasive species requires identifying the factors that determine alien species invasion success.This study investigates how anthropogenic and biogeographical factors influence alien plant invasion in the Sanyang Wetlands,a human-dominated island system in Wenzhou City,China.Specifically,we analyzed whether human activities(e.g.,habitat heterogeneity,proportion of road area,and cultivation)and island characteristics(e.g.,island area,isolation)affect the diversity of native and invasive plant species similarly.We also assessed the applicability of the equilibrium theory of island biogeography to invasive plant species diversity and examined how these factors affect invasive plant species with different dispersal syndromes(anemochore,zoochore,and autochore).We found that both invasive and native species richness positively correlate with island area,habitat heterogeneity,and proportion of road area.However,although native species richness was negatively correlated with isolation,invasive species richness was not.The diversity and composition of invasive species with different dispersal syndromes were determined by different variables;for example,the composition and diversity of zoochores was increased by habitat heterogeneity,while anemochore species richness was increased by the proportion of road area,whereas anemochore species composition was influenced by distance to the nearest island.We conclude that habitat fragmentation differentially affects invasive and native plant diversity,aligning with the predictions of the equilibrium theory of island biogeography only for native species but not for invasive species.Our findings indicate that tailoring habitat attributes and regulating human activities could be effective strategies for mitigating the spread of invasive species in fragmented landscapes. 展开更多
关键词 Alien species invasion Dispersal strategies Human disturbance Island attributes Island biogeography theory WETLAND
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MACLSTM: A Weather Attributes Enabled Recurrent Approach to Appliance-Level Energy Consumption Forecasting
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作者 Ruoxin Li Shaoxiong Wu +5 位作者 Fengping Deng Zhongli Tian Hua Cai Xiang Li Xu Xu Qi Liu 《Computers, Materials & Continua》 2025年第2期2969-2984,共16页
Studies to enhance the management of electrical energy have gained considerable momentum in recent years. The question of how much energy will be needed in households is a pressing issue as it allows the management pl... Studies to enhance the management of electrical energy have gained considerable momentum in recent years. The question of how much energy will be needed in households is a pressing issue as it allows the management plan of the available resources at the power grids and consumer levels. A non-intrusive inference process can be adopted to predict the amount of energy required by appliances. In this study, an inference process of appliance consumption based on temporal and environmental factors used as a soft sensor is proposed. First, a study of the correlation between the electrical and environmental variables is presented. Then, a resampling process is applied to the initial data set to generate three other subsets of data. All the subsets were evaluated to deduce the adequate granularity for the prediction of the energy demand. Then, a cloud-assisted deep neural network model is designed to forecast short-term energy consumption in a residential area while preserving user privacy. The solution is applied to the consumption data of four appliances elected from a set of real household power data. The experiment results show that the proposed framework is effective for estimating consumption with convincing accuracy. 展开更多
关键词 Electrical load forecasting cloud computing smart grid weather attributes energy consumption time-series analysis
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Features of Prime Attributes in a Relation Scheme
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作者 XU Yulu LIU Guohua +4 位作者 YU Xiaoxue LIU Changqi ZHU Dongyan ZHANG Limeng HE Songda 《Journal of Donghua University(English Edition)》 2025年第6期689-698,共10页
Normal forms have a significant role in the theory of relational database normalization.The definitions of normal forms are established through the functional dependency(FD)relationship between a prime or nonprime att... Normal forms have a significant role in the theory of relational database normalization.The definitions of normal forms are established through the functional dependency(FD)relationship between a prime or nonprime attribute and a key.However,determining whether an attribute is a prime attribute is a nondeterministic polynomial-time complete(NP-complete)problem,making it intractable to determine if a relation scheme is in a specific normal form.While the prime attribute problem is generally NP-complete,there are cases where identifying prime attributes is not challenging.In a relation scheme R(U,F),we partition U into four distinct subsets based on where attributes in U appear in F:U_(1)(attributes only appearing on the left-hand side of FDs),U_(2)(attributes only appearing on the right-hand side of FDs),U_(3)(attributes appearing on both sides of FDs),and U_(4)(attributes not present in F).Next,we demonstrate the necessary and sufficient conditions for a key to be the unique key of a relation scheme.Subsequently,we illustrate the features of prime attributes in U_(3) and generalize the features of common prime attributes.The findings lay the groundwork for distinguishing between complex and simple cases in prime attribute identification,thereby deepening the understanding of this problem. 展开更多
关键词 NORMALIZATION KEY prime attribute nonprime attribute
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Factors shaping the distribution of old-growthness attributes in the forests of Spain
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作者 Adrià Cos Javier Retana Jordi Vayreda 《Forest Ecosystems》 2025年第2期243-252,共10页
Conservation and enhancement of old-growth forests are key in forest planning and policies.In order to do so,more knowledge is needed on how the attributes traditionally associated with old-growth forests are distribu... Conservation and enhancement of old-growth forests are key in forest planning and policies.In order to do so,more knowledge is needed on how the attributes traditionally associated with old-growth forests are distributed in space,what differences exist across distinct forest types and what natural or anthropic conditions are affecting the distribution of these old-growthness attributes.Using data from the Third Spanish National Forest Inventory(1997–2007),we calculated six indicators commonly associated with forest old-growthness for the plots in the territory of Peninsular Spain and Balearic Islands,and then combined them into an aggregated index.We then assessed their spatial distribution and the differences across five forest functional types,as well as the effects of ten climate,topographic,landscape,and anthropic variables in their distribution.Relevant geographical patterns were apparent,with climate factors,namely temperature and precipitation,playing a crucial role in the distribution of these attributes.The distribution of the indicators also varied across different forest types,while the effects of recent anthropic impacts were weaker but still relevant.Aridity seemed to be one of the main impediments for the development of old-growthness attributes,coupled with a negative impact of recent human pressure.However,these effects seemed to be mediated by other factors,specially the legacies imposed by the complex history of forest management practices,land use changes and natural disturbances that have shaped the forests of Spain.The results of this exploratory analysis highlight on one hand the importance of climate in the dynamic of forests towards old-growthness,which is relevant in a context of Climate Change,and on the other hand,the need for more insights on the history of our forests in order to understand their present and future. 展开更多
关键词 Old-growth forests Forest old-growthness Forest old-growthness attributes Spanish national forest inventory Forest functional types Spain
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Attribution of psychiatric manifestations to systemic lupus erythematosus in Chinese patients:A retrospective study
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作者 Wen-Qi Geng Xiao-Xi Yang +3 位作者 Jin-Ya Cao Shang-Zhu Zhang Yi-Nan Jiang Jing Wei 《World Journal of Psychiatry》 2025年第2期76-84,共9页
BACKGROUND Not all neuropsychiatric(NP)manifestations in patients with systemic lupus erythematosus(SLE)are secondary to lupus.The clarification of the cause of NP symptoms influences therapeutic strategies for SLE.AI... BACKGROUND Not all neuropsychiatric(NP)manifestations in patients with systemic lupus erythematosus(SLE)are secondary to lupus.The clarification of the cause of NP symptoms influences therapeutic strategies for SLE.AIM To understand the attribution of psychiatric manifestations in a cohort of Chinese patients with SLE.METHODS This retrospective single-center study analyzed 160 inpatient medical records.Clinical diagnosis,which is considered the gold standard,was used to divide the subjects into a psychiatric SLE(PSLE)group(G1)and a secondary psychiatric symptoms group(G2).Clinical features were compared between these two groups.The sensitivity and specificity of the Italian attribution model were explored.RESULTS A total of 171 psychiatric syndromes were recorded in 138 patients,including 87 cases of acute confusional state,40 cases of cognitive dysfunction,18 cases of psychosis,and 13 cases each of depressive disorder and mania or hypomania.A total of 141(82.5%)syndromes were attributed to SLE.In contrast to G2 patients,G1 patients had higher SLE Disease Activity Index-2000 scores(21 vs 12,P=0.001),a lower prevalence of anti-beta-2-glycoprotein 1 antibodies(8.6%vs 25.9%,P=0.036),and a higher prevalence of anti-ribosomal ribonucleoprotein particle(rRNP)antibodies(39.0%vs 22.2%,P=0.045).The Italian attribution model exhibited a sensitivity of 95.0%and a specificity of 70.0%when the threshold value was set at 7.CONCLUSION Patients with PSLE exhibited increased disease activity.There is a correlation between PSLE and anti-rRNP antibodies.The Italian model effectively assesses multiple psychiatric manifestations in Chinese SLE patients who present with NP symptoms. 展开更多
关键词 systemic lupus erythematosus Neuropsychiatric systemic lupus erythematosus ATTRIBUTION Italian attribution model Referral consultation
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A Study on Re-Identification of Natural Language Data Considering Korean Attributes
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作者 Segyeong Bang Soeun Kim +2 位作者 Gaeun Ahn Hyemin Hong Junhyoung Oh 《Computers, Materials & Continua》 2025年第12期4629-4643,共15页
This study analyzes the risks of re-identification in Korean text data and proposes a secure,ethical approach to data anonymization.Following the‘Lee Luda’AI chatbot incident,concerns over data privacy have increase... This study analyzes the risks of re-identification in Korean text data and proposes a secure,ethical approach to data anonymization.Following the‘Lee Luda’AI chatbot incident,concerns over data privacy have increased.The Personal Information Protection Commission of Korea conducted inspections of AI services,uncovering 850 cases of personal information in user input datasets,highlighting the need for pseudonymization standards.While current anonymization techniques remove personal data like names,phone numbers,and addresses,linguistic features such as writing habits and language-specific traits can still identify individuals when combined with other data.To address this,we analyzed 50,000 Korean text samples from the X platform,focusing on language-specific features for authorship attribution.Unlike English,Korean features flexible syntax,honorifics,syllabic and grapheme patterns,and referential terms.These linguistic characteristics were used to enhance re-identification accuracy.Our experiments combined five machine learning models,six stopword processing methods,and four morphological analyzers.By using a tokenizer that captures word frequency and order,and employing the LSTM model,OKT morphological analyzer,and stopword removal,we achieved the maximum authorship attributions accuracy of 90.51%.This demonstrates the significant role of Korean linguistic features in re-identification.The findings emphasize the risk of re-identification through language data and call for a re-evaluation of anonymization methods,urging the consideration of linguistic traits in anonymization beyond simply removing personal information. 展开更多
关键词 Re-identification data anonymization authorship attributions Korean text
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Effects of rice cropping method and growth stage on rhizosphere bacterial diversity and soil biological attributes
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作者 Surathi ADITHYA Sai Aparna Devi NUNNA +1 位作者 Chinnappan CHINNADURAI Dananjeyan BALACHANDAR 《Pedosphere》 2025年第6期983-994,共12页
Rice cropping method is primarily decided by soil moisture regime.System of rice intensification(SRI)and direct-seeded aerobic rice are two primary modifications of traditional wetland rice.Understanding rice rhizosph... Rice cropping method is primarily decided by soil moisture regime.System of rice intensification(SRI)and direct-seeded aerobic rice are two primary modifications of traditional wetland rice.Understanding rice rhizosphere microbiome and functioning as influenced by these cropping methods is essential for sustaining rice productivity.The objective of this study was to assess the impact of three different rice cropping methods(wetland rice,SRI,and aerobic rice)on the biochemical properties and bacterial communities within the rice rhizosphere across three key rice growth stages:tillering,flowering,and maturity.Soil organic carbon(SOC),microbial biomass carbon(MBC),dehydrogenase activity,substrate-induced respiration(SIR),and metabolic quotient(MQ)were assessed along with high-throughput 16S rRNA sequencing of rice rhizosphere soils.The rice rhizosphere soil registered the highest SOC,MBC,and dehydrogenase activity in SRI followed by wetland rice and then aerobic rice.Cropping method had a minimal impact on SIR and MQ.Along with cropping method,growth stage also significantly altered these biological attributes of rice rhizosphere.The trends of the highest SOC content and dehydrogenase activity at the flowering stage and the highest MBC content and SIR at the tillering stage of rice were observed in all three rice cropping methods.The analysis of bacterial communities,based on 16S rRNA gene sequencing,revealed that both cropping method and growth stage significantly impacted the composition of rhizosphere microbiomes.However,the influence of cropping method was less pronounced compared to growth stage.Cropping method caused notable shifts in the abundances of Proteobacteria,Bacteroidetes,and Chloroflexi,while growth stage affected the abundances of Proteobacteria,Actinobacteria,Cyanobacteria,Firmicutes,Chloroflexi,and Bacteroidetes.Based on these results,the SRI method led to higher diversification to the rhizosphere bacteriobiota,as well as greater incorporation of carbon into the soil and increased dehydrogenase activity compared to wetland rice and aerobic rice.This study deepens our understanding of how different cropping methods influence plant-microbe interaction and the implications for overall rice productivity and soil health. 展开更多
关键词 bacterial communities direct-seeded aerobic rice metabolic quotient soil biological attribute substrate-induced respiration system of rice intensification
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Extracting useful information from sparsely logged wellbores for improved rock typing of heterogeneous reservoir characterization using well-log attributes, feature influence and optimization
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作者 David A.Wood 《Petroleum Science》 2025年第6期2307-2311,共5页
The information from sparsely logged wellbores is currently under-utilized in reservoir simulation models and their proxies using deep and machine learning (DL/ML).This is particularly problematic for large heterogene... The information from sparsely logged wellbores is currently under-utilized in reservoir simulation models and their proxies using deep and machine learning (DL/ML).This is particularly problematic for large heterogeneous gas/oil reservoirs being considered for repurposing as gas storage reservoirs for CH_(4),CO_(2) or H_(2) and/or enhanced oil recovery technologies.Lack of well-log data leads to inadequate spatial definition of complex models due to the large uncertainties associated with the extrapolation of petrophysical rock types (PRT) calibrated with limited core data across heterogeneous and/or anisotropic reservoirs.Extracting well-log attributes from the few well logs available in many wells and tying PRT predictions based on them to seismic data has the potential to substantially improve the confidence in PRT 3D-mapping across such reservoirs.That process becomes more efficient when coupled with DL/ML models incorporating feature importance and optimized,dual-objective feature selection techniques. 展开更多
关键词 Petrophysical/geomechanical rock typing Log attribute calculations Heterogeneous reservoir characterization Core-well-log-seismic integration Feature selection influences
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Using 4C OBS to reveal the distribution and velocity attributes of gas hydrates at the northern continental slope of South China Sea 被引量:7
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作者 沙志彬 张明 +2 位作者 张光学 梁金强 苏丕波 《Applied Geophysics》 SCIE CSCD 2015年第4期555-563,628,629,共11页
To investigate the distribution and velocity attributes of gas hydrates in the northern continental slope of South China Sea, Guangzhou Marine Geological Survey conducted four-component (4C) ocean-bottom seismometer... To investigate the distribution and velocity attributes of gas hydrates in the northern continental slope of South China Sea, Guangzhou Marine Geological Survey conducted four-component (4C) ocean-bottom seismometer (OBS) surveys. A case study is presented to show the results of acquiring and processing OBS data for detecting gas hydrates. Key processing steps such as repositioning, reorientation, PZ summation, and mirror imaging are discussed. Repositioning and reorientation find the correct location and direction of nodes. PZ summation matches P- and Z-components and sums them to separate upgoing and downgoing waves. Upgoing waves are used in conventional imaging, whereas downgoing waves are used in mirror imaging. Mirror imaging uses the energy of the receiver ghost reflection to improve the illumination of shallow structures, where gas hydrates and the associated bottom-simulating reflections (BSRs) are located. We developed a new method of velocity analysis using mirror imaging. The proposed method is based on velocity scanning and iterative prestack time migration. The final imaging results are promising. When combined with the derived velocity field, we can characterize the BSR and shallow structures; hence, we conclude that using 4C OBS can reveal the distribution and velocity attributes of gas hydrates. 展开更多
关键词 gas hydrates velocity attributes ocean-bottom seismometer PZ summation mirror imaging
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Quantitative prediction of channel sand bodies based on seismic peak attributes in the frequency domain and its application 被引量:2
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作者 孙鲁平 郑晓东 +2 位作者 首皓 李劲松 李艳东 《Applied Geophysics》 SCIE CSCD 2010年第1期10-17,98,共9页
The boundary identification and quantitative thickness prediction of channel sand bodies are always difficult in seismic exploration.We present a new method for boundary identification and quantitative thickness predi... The boundary identification and quantitative thickness prediction of channel sand bodies are always difficult in seismic exploration.We present a new method for boundary identification and quantitative thickness prediction of channel sand bodies based on seismic peak attributes in the frequency domain.Using seismic forward modeling of a typical thin channel sand body,a new seismic attribute-the ratio of peak frequency to amplitude was constructed.Theoretical study demonstrated that seismic peak frequency is sensitive to the thickness of the channel sand bodies,while the amplitude attribute is sensitive to the strata lithology.The ratio of the two attributes can highlight the boundaries of the channel sand body.Moreover,the thickness of the thin channel sand bodies can be determined using the relationship between seismic peak frequency and thin layer thickness.Practical applications have demonstrated that the seismic peak frequency attribute can depict the horizontal distribution characteristics of channels very well.The ratio of peak frequency to amplitude attribute can improve the identification ability of channel sand body boundaries.Quantitative prediction and boundary identification of channel sand bodies with seismic peak attributes in the frequency domain are feasible. 展开更多
关键词 channel sand bodies seismic peak frequency attribute seismic peak amplitude attribute boundary identification quantitative prediction
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Application of multiple attributes fusion technology in the Su-14 Well Block 被引量:2
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作者 王兴建 胡光岷 曹俊兴 《Applied Geophysics》 SCIE CSCD 2010年第3期257-264,293,共9页
In this study area the geological conditions are complicated and the effective sandstone is very heterogeneous.The sandstones are thin and lateral and vertical variations are large.We introduce multi-attribute fusion ... In this study area the geological conditions are complicated and the effective sandstone is very heterogeneous.The sandstones are thin and lateral and vertical variations are large.We introduce multi-attribute fusion technology based on pre-stack seismic data, pre-stack P-and S-wave inversion results,and post-stack attributes.This method not only can keep the fluid information contained in pre-stack seismic data but also make use of the high SNR characteristics of post-stack data.First,we use a one-step recursive method to get the optimal attribute combination from a number of attributes.Second,we use a probabilistic neural network method to train the nonlinear relationship between log curves and seismic attributes and then use the trained samples to find the natural gamma ray distribution in the Su-14 well block and improve the resolution of seismic data.Finally,we predict the effective reservoir distribution in the Su-14 well block. 展开更多
关键词 multiple attributes fusion neural network interactive validation Su-14 well block
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Ordovician limestone aquosity prediction using nonlinear seismic attributes:Case from the Xutuan coal mine
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作者 黄亚平 董守华 耿建华 《Applied Geophysics》 SCIE CSCD 2009年第4期359-366,394,395,共10页
Ordovician limestone water is coal mines. In this paper, we analyze the the main source of water inrush in North China characteristic of three kinds of nonlinear seismic attributes, such as the largest lyapunov expone... Ordovician limestone water is coal mines. In this paper, we analyze the the main source of water inrush in North China characteristic of three kinds of nonlinear seismic attributes, such as the largest lyapunov exponent,fractal dimension and entropy and introduce their calculation methods. Taking the 81st and 82nd coal districts in the Xutuan coal mine as examples, we extract the three seismic attributes based on the 3D prestack migration seismic data of this area, which can display the Ordovician limestone fracture distribution in the mine. We comprehensively analyzed the three nonlinear seismic attributes and compared the results with transient electromagnetic exploration results and determined the possible Ordovician limestone aquosity distribution. This demonstrated that the nonlinear seismic attributes technology is an effective approach to predict the aquosity of Ordovician limestone. 展开更多
关键词 nonlinear seismic attribute LIMESTONE aquosity PREDICTION
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The Observed and Projected Changes of Global Monsoons:Current Status and Future Perspectives
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作者 Tianjun ZHOU Xiaolong CHEN +11 位作者 Wenxia ZHANG Bo WU Ziming CHEN Jie JIANG Xin HUANG Shuai HU Meng ZUO Wenmin MAN Lixia ZHANG Zhun GUO Pengfei LIN Lu WANG 《Advances in Atmospheric Sciences》 2026年第1期30-58,共29页
The global monsoon system,encompassing the Asian-Australian,African,and American monsoons,sustains two-thirds of the world’s population by regulating water resources and agriculture.Monsoon anomalies pose severe risk... The global monsoon system,encompassing the Asian-Australian,African,and American monsoons,sustains two-thirds of the world’s population by regulating water resources and agriculture.Monsoon anomalies pose severe risks,including floods and droughts.Recent research associated with the implementation of the Global Monsoons Model Intercomparison Project under the umbrella of CMIP6 has advanced our understanding of its historical variability and driving mechanisms.Observational data reveal a 20th-century shift:increased rainfall pre-1950s,followed by aridification and partial recovery post-1980s,driven by both internal variability(e.g.,Atlantic Multidecadal Oscillation)and external forcings(greenhouse gases,aerosols),while ENSO drives interannual variability through ocean-atmosphere interactions.Future projections under greenhouse forcing suggest long-term monsoon intensification,though regional disparities and model uncertainties persist.Models indicate robust trends but struggle to quantify extremes,where thermodynamic effects(warming-induced moisture rise)uniformly boost heavy rainfall,while dynamical shifts(circulation changes)create spatial heterogeneity.Volcanic eruptions and proposed solar radiation modification(SRM)further complicate predictions:tropical eruptions suppress monsoons,whereas high-latitude events alter cross-equatorial flows,highlighting unresolved feedbacks.The emergent constraint approach is booming in terms of correcting future projections and reducing uncertainty with respect to the global monsoons.Critical challenges remain.Model biases and sparse 20th-century observational data hinder accurate attribution.The interplay between natural variability and anthropogenic forcings,along with nonlinear extreme precipitation risks under warming,demands deeper mechanistic insights.Additionally,SRM’s regional impacts and hemispheric monsoon interactions require systematic evaluation.Addressing these gaps necessitates enhanced observational networks,refined climate models,and interdisciplinary efforts to disentangle multiscale drivers,ultimately improving resilience strategies for monsoon-dependent regions. 展开更多
关键词 global monsoons interannual variability decadal variability detection and attribution climate extreme events projection uncertainty
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The Location Differences of Attributes in EST Translation
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作者 李清平 黄晨 《海外英语》 2013年第18期137-138,共2页
There are similarities and differences about the order of the attributes between English sentences and Chinese sentenc es. As a result, mistakes can often be observed; those mistakes are the results of unfamiliarity w... There are similarities and differences about the order of the attributes between English sentences and Chinese sentenc es. As a result, mistakes can often be observed; those mistakes are the results of unfamiliarity with the proper order of the attri butes. But here, special attention is paid to the EST(English for Science and Technology) translation in which their differences are much more distinct. Generally speaking, the attributes in English can be divided into pre-attributes and post-attributes in terms of their positions in a sentence. But in Chinese an attribute is usually put before a noun, and rarely put after it, so several simple comparisons are tried to find out some rules to translate English attributes into Chinese. 展开更多
关键词 ATTRIBUTE EST Order LOCATION TRANSLATION
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