期刊文献+
共找到6篇文章
< 1 >
每页显示 20 50 100
Accessing global soil raster images and equal-area splines to estimate soil organic carbon stocks on the regional scale
1
作者 Trevan FLYNN Rosana KOSTECKI +1 位作者 Ansa REBI Taqi RAZA 《Pedosphere》 2025年第5期834-845,共12页
Soil carbon stock research has gained prominence in environmental studies amidst climate change concerns,especially given that soil is one of the largest terrestrial carbon reserves.Accurate predictions necessitate co... Soil carbon stock research has gained prominence in environmental studies amidst climate change concerns,especially given that soil is one of the largest terrestrial carbon reserves.Accurate predictions necessitate comprehensive soil profile measurements,which are resource-intensive to obtain.To address this,depth functions are employed to derive continuous estimates,aligning with standardized depths.However,global datasets employing depth functions in raster format have not been widely utilized,which could lower financial costs and improve accuracy in data-scarce regions.Furthermore,research into aggregating depth functions for realistic carbon stock estimations remains limited,offering opportunities to streamline cost and time.The aim of this study was to apply equal-area splines to estimate soil carbon stocks,utilizing SoilGrids and iSDAsoil datasets in a 317-km^(2) Quaternary catchment(30°48′E,29°18′S)in KwaZulu-Natal,South Africa.Both datasets were resampled to a 250-m resolution,and the splines were interpolated to a depth of 50 cm per pixel.Various aggregation methods were employed in calculation,including the cumulative sum(definite integral),discrete sum(sum of 1-cm spline predictions),and the mean carbon stock(mean to 50 cm).Quantitative evaluation was performed with 310 external soil samples.SoilGrids showed higher predictions(100–546 kg m^(-2))than iSDAsoil(66.9–225 kg m^(-2))for the cumulative sum.The discrete sum also exhibited higher prediction values for SoilGrids(293–789 kg m^(-2))compared to iSDAsoil(228–557 kg m^(-2)).SoilGrids aggregated with the discrete sum closely matched previous studies,estimating total carbon stock for the catchment at 7126 t,albeit with spatial inconsistencies.However,when evaluating with an external dataset,the results were not satisfactory for any method according to Lin's concordance correlation coefficient(CCC,correlation of a 1:1 line),with all models obtaining a CCC below 0.01.Similarly,all models had a root mean squared error larger than 59 kg m^(-2).It was concluded that SoilGrids and iSDAsoil were spatially inaccurate in the catchment but can still provide information about the total carbon stock.This method could be improved by obtaining more soil samples for the datasets,incorporating local data into the spline,making the method more computationally efficient,and accounting for discrete horizon boundaries. 展开更多
关键词 depth distribution depth function global dataset Google Earth Engine normalized difference prediction index South Africa
原文传递
Reversible Data Hiding Algorithm in Encrypted Images Based on Arithmetic Coding and Dual Prediction
2
作者 Mengyuan Zhang Xinyi Zeng +2 位作者 Tonghui Liu Tong Zhu Wanli Lyuenv 《国际计算机前沿大会会议论文集》 2025年第1期567-586,共20页
Reversible data hiding in encrypted images(RDH-EI)enables the concealment of secret data within ciphertext images while preserving the ability to fully recover both the original image and the hidden message.However,ex... Reversible data hiding in encrypted images(RDH-EI)enables the concealment of secret data within ciphertext images while preserving the ability to fully recover both the original image and the hidden message.However,existing RDH-EI schemes based on vacating room after encryption(VRAE)suffer from limited embedding capacity.To address this issue,we propose a method based on arithmetic coding and dual prediction for encrypted images.First,the original image is encrypted with a chunked modulus and permutation.Then,using the upper-left corner pixel of each subblock as a reference,adaptive MSB prediction and difference prediction are employed to predict the remaining pixels within the subblock.The resulting label map is then compressed via arithmetic coding to vacate the embedding space for the secret message.Finally,the separable operations of the original image restoration and secret message extraction can be performed on the basis of the type of key possessed.The experimental results demonstrate that the proposed algorithm not only successfully extracts the secret information but also recovers the original image without any loss.Furthermore,it effectively enhances the embedding capacity by fully utilizing the correlation between adjacent pixels while ensuring the security of the image. 展开更多
关键词 Reversible data hiding Adaptive difference prediction Adaptive MSB prediction Arithmetic coding
原文传递
Convergence of Y Chromosome STR Haplotypes from Different SNP Haplogroups Compromises Accuracy of Haplogroup Prediction 被引量:9
3
作者 Chuan-Chao Wang Ling-Xiang Wang +5 位作者 Rukesh Shrestha Shaoqing Wen Manfei Zhang Xinzhu Tong Li Jin Hui Li 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2015年第7期403-407,共5页
The paternally inherited Y chromosome has been widely used in forensics for personal identification, in anthropology and population genetics to understand origin and migration of human populations, and also in medical... The paternally inherited Y chromosome has been widely used in forensics for personal identification, in anthropology and population genetics to understand origin and migration of human populations, and also in medical and clinical studies (Wang and Li, 2013; Wang et al., 2014). There are two kinds of extremely useful markers in Y chromosome, single nucle- otide polymorphism (SNP) and short tandem repeats (STRs). With a very low mutation rate on the order of 3.0 x 10-8 mutations/nucleotide/generation (Xue et al., 2009), SNP markers have been used in constructing a robust phylogeny tree linking all the Y chromosome lineages from world pop- ulations (Karafet et al., 2008). Those lineages determined by the pattern of SNPs are called haplogroups. That is to say, we have to genotype an appropriate number of SNPs in order to assign a given Y chromosome to a haplogroup. Compared with SNPs, the mutation rates of STR markers are about four to five orders of magnitude higher (Gusmgo et al., 2005; Ballantyne et al., 2010). Typing STR has advantages of saving time and cost compared with typing SNPs in phylogenetic assignment of a Y chromosome (Wang et al., 2010). A set of STR values for an individual is called a haplotype. Because of the disparity in mutation rates between SNP and STR, one SNP haplogroup could actually comprise many STR haplotypes (Wang et al., 2010). It is most interesting that STR variability is clustered more by haplogroups than by populations (Bosch et al., 1999; Behar et al., 2004), which indicates that STR haplotypes could be used to infer the haplogroup information of a given Y chromosome. There has been increasing interest in this cost- effective strategy for predicting the haplogroup from a given STR haplotype when SNP data are unavailable. For instance, Vadim Urasin's YPredictor (http://predictor.ydna.ru/), Whit Atheys' haplogroup predictor (http://www.hprg.com/hapest5/) (Athey, 2005, 2006), and haplogroup classifier of Arizona University (Schlecht et al., 2008) have been widely employed in previous studies for haplogroup prediction (Larmuseau et al., 2010; Bembea et al., 2011; Larmuseau et al., 2012; Tarlykov et al., 2013). 展开更多
关键词 STR Convergence of Y Chromosome STR Haplotypes from Different SNP Haplogroups Compromises Accuracy of Haplogroup Prediction SNP SNPs
原文传递
Gray Matter-Based Age Prediction Characterizes Different Regional Patterns
4
作者 Nianming Zuo Tianyu Hu +3 位作者 Hao Liu Jing Sui Yong Liu Tianzi Jiang 《Neuroscience Bulletin》 SCIE CAS CSCD 2021年第1期94-98,共5页
Dear Editor,The brain experiences ongoing changes across different ages to support brain development and functional reorganization.During the span of adulthood,although the brain has matured from a neurobiological per... Dear Editor,The brain experiences ongoing changes across different ages to support brain development and functional reorganization.During the span of adulthood,although the brain has matured from a neurobiological perspective,it is still continuously shaped by external factors such as habits,the family setting,socioeconomic status,and the work environment [1].In contrast to chronological age (CA),brain(or biological) age (BA) is conceptualized as an important index for characterizing the aging process and neuropsychological state,as well as individual cognitiveperformance.Growing evidence indicates that BA can be assessed by neuroimaging techniques,including MRI [2]. 展开更多
关键词 Gray Matter-Based Age Prediction Characterizes Different Regional Patterns
原文传递
Prediction of groundwater level in Indonesian tropical peatland forest plantations using machine learning
5
作者 Kazuo Yonekura Sota Miyazaki +3 位作者 Masaatsu Aichi Takafumi Nishizu Masao Hasegawa Katsuyuki Suzuki 《Artificial Intelligence in Geosciences》 2025年第2期177-183,共7页
Maintaining high groundwater level(GWL)is important for preventing fires in peatlands.This study proposes GWL prediction using machine learning methods for forest plantations in Indonesian tropical peatlands.Deep neur... Maintaining high groundwater level(GWL)is important for preventing fires in peatlands.This study proposes GWL prediction using machine learning methods for forest plantations in Indonesian tropical peatlands.Deep neural networks(DNN)have been used for prediction;however,they have not been applied to groundwater prediction in Indonesian peatlands.Tropical peatland is characterized by high permeability and forest plantations are surrounded by several canals.By predicting daily differences in GWL,the GWL can be predicted with high accuracy.DNNs,random forests,support vector regression,and XGBoost were compared,all of which indicated similar errors.The SHAP value revealed that the precipitation falling on the hill rapidly seeps into the soil and flows into the canals,which agrees with the fact that the soil has high permeability.These findings can potentially be used to alleviate and manage future fires in peatlands. 展开更多
关键词 predicting daily differences gwlthe machine learning maintaining high groundwater groundwater prediction machine learning methods groundwater level prediction deep neural networks neural networks dnn
在线阅读 下载PDF
Enhancement of IoT device security using an Improved Elliptic Curve Cryptography algorithm and malware detection utilizing deep LSTM
6
作者 R.Aiyshwariya Devi A.R.Arunachalam 《High-Confidence Computing》 2023年第2期18-31,共14页
Internet of things(IoT)has become more popular due to the development and potential of smart technology aspects.Security concerns against IoT infrastructure,applications,and devices have grown along with the need for ... Internet of things(IoT)has become more popular due to the development and potential of smart technology aspects.Security concerns against IoT infrastructure,applications,and devices have grown along with the need for IoT technologies.Enhanced system security protocols are difficult due to the diverse capabilities of IoT devices and the dynamic,ever-changing environment,and simply applying basic security requirements is dangerous.Therefore,this proposed work designs a malware detection and prevention approach for secure data transmission among IoT gadgets.The malware detection approach is designed with the aid of a deep learning approach.The initial process is identifying attack nodes from normal nodes through a trust value using contextual features.After discovering attack nodes,these are considered for predicting different kinds of attacks present in the network,while some preprocessing and feature extraction strategies are applied for effective classification.The Deep LSTM classifier is applied for this malware detection approach.Once completed malware detection,prevention is performed with the help of the Improved Elliptic Curve Cryptography(IECC)algorithm.A hybrid MA-BW optimization is adopted for selecting the optimal key during transmission.Python 3.8 software is used to test the performance of the proposed approach,and several existing techniques are considered to evaluate its performance.The proposed approach obtained 95%of accuracy,5%of error value and 92%of precision.In addition,the improved ECC algorithm is also compared with some existing algorithm which takes 6.02 s of execution time.Compared to the other methods,the proposed approach provides better security to IoT gadgets during data transmission. 展开更多
关键词 Deep LSTM Improved Elliptic Curve CRYPTOGRAPHY Malware detection Prediction of different kinds of attacks IoT gadgets
在线阅读 下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部