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Integrating vegetation phenological characteristics and polarization features with object-oriented techniques for grassland type identification 被引量:1
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作者 Bin Sun Pengyao Qin +5 位作者 Changlong Li Zhihai Gao Alan Grainger Xiaosong Li Yan Wang Wei Yue 《Geo-Spatial Information Science》 CSCD 2024年第3期794-810,共17页
Due to the small size,variety,and high degree of mixing of herbaceous vegetation,remote sensing-based identification of grassland types primarily focuses on extracting major grassland categories,lacking detailed depic... Due to the small size,variety,and high degree of mixing of herbaceous vegetation,remote sensing-based identification of grassland types primarily focuses on extracting major grassland categories,lacking detailed depiction.This limitation significantly hampers the development of effective evaluation and fine supervision for the rational utilization of grassland resources.To address this issue,this study concentrates on the representative grassland of Zhenglan Banner in Inner Mongolia as the study area.It integrates the strengths of Sentinel-1 and Sentinel-2 active-passive synergistic observations and introduces innovative object-oriented techniques for grassland type classification,thereby enhancing the accuracy and refinement of grassland classification.The results demonstrate the following:(1)To meet the supervision requirements of grassland resources,we propose a grassland type classification system based on remote sensing and the vegetation-habitat classification method,specifically applicable to natural grasslands in northern China.(2)By utilizing the high-spatial-resolution Normalized Difference Vegetation Index(NDVI)synthesized through the Spatial and Temporal Non-Local Filter-based Fusion Model(STNLFFM),we are able to capture the NDVI time profiles of grassland types,accurately extract vegetation phenological information within the year,and further enhance the temporal resolution.(3)The integration of multi-seasonal spectral,polarization,and phenological characteristics significantly improves the classification accuracy of grassland types.The overall accuracy reaches 82.61%,with a kappa coefficient of 0.79.Compared to using only multi-seasonal spectral features,the accuracy and kappa coefficient have improved by 15.94%and 0.19,respectively.Notably,the accuracy improvement of the gently sloping steppe is the highest,exceeding 38%.(4)Sandy grassland is the most widespread in the study area,and the growth season of grassland vegetation mainly occurs from May to September.The sandy meadow exhibits a longer growing season compared with typical grassland and meadow,and the distinct differences in phenological characteristics contribute to the accurate identification of various grassland types. 展开更多
关键词 Grassland types vegetation phenological characteristics polarization feature integrated active and passive remote sensing object-oriented classification
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X-OODM:Leveraging Explainable Object-Oriented Design Methodology for Multi-Domain Sentiment Analysis
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作者 Abqa Javed Muhammad Shoaib +2 位作者 Abdul Jaleel Mohamed Deriche Sharjeel Nawaz 《Computers, Materials & Continua》 2025年第3期4977-4994,共18页
Incorporation of explainability features in the decision-making web-based systems is considered a primary concern to enhance accountability,transparency,and trust in the community.Multi-domain Sentiment Analysis is a ... Incorporation of explainability features in the decision-making web-based systems is considered a primary concern to enhance accountability,transparency,and trust in the community.Multi-domain Sentiment Analysis is a significant web-based system where the explainability feature is essential for achieving user satisfaction.Conventional design methodologies such as object-oriented design methodology(OODM)have been proposed for web-based application development,which facilitates code reuse,quantification,and security at the design level.However,OODM did not provide the feature of explainability in web-based decision-making systems.X-OODM modifies the OODM with added explainable models to introduce the explainability feature for such systems.This research introduces an explainable model leveraging X-OODM for designing transparent applications for multidomain sentiment analysis.The proposed design is evaluated using the design quality metrics defined for the evaluation of the X-OODM explainable model under user context.The design quality metrics,transferability,simulatability,informativeness,and decomposability were introduced one after another over time to the evaluation of the X-OODM user context.Auxiliary metrics of accessibility and algorithmic transparency were added to increase the degree of explainability for the design.The study results reveal that introducing such explainability parameters with X-OODM appropriately increases system transparency,trustworthiness,and user understanding.The experimental results validate the enhancement of decision-making for multi-domain sentiment analysis with integration at the design level of explainability.Future work can be built in this direction by extending this work to apply the proposed X-OODM framework over different datasets and sentiment analysis applications to further scrutinize its effectiveness in real-world scenarios. 展开更多
关键词 Measurable explainable web-based application object-oriented design sentiment analysis MULTI-DOMAIN
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Research on Building Extraction Based on Object-oriented CART Classification Algorithm and GF-2 Satellite Images
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作者 HUANG Wei CUI Zhimei +1 位作者 HUANG Zhidu WU Rongrong 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第4期5-18,共14页
As one of the main geographical elements in urban areas,buildings are closely related to the development of the city.Therefore,how to quickly and accurately extract building information from remote sensing images is o... As one of the main geographical elements in urban areas,buildings are closely related to the development of the city.Therefore,how to quickly and accurately extract building information from remote sensing images is of great significance for urban map updating,urban planning and construction,etc.Extracting building information around power facilities,especially obtaining this information from high-resolution images,has become one of the current hot topics in remote sensing technology research.This study made full use of the characteristics of GF-2 satellite remote sensing images,adopted an object-oriented classification method,combined with multi-scale segmentation technology and CART classification algorithm,and successfully extracted the buildings in the study area.The research results showed that the overall classification accuracy reached 89.5%and the Kappa coefficient was 0.86.Using the object-oriented CART classification algorithm for building extraction could be closer to actual ground objects and had higher accuracy.The extraction of buildings in the city contributed to urban development planning and provided decision support for management. 展开更多
关键词 object-oriented high-resolution image image segmentation CART decision tree building extraction
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Meta-analysis of potentially confounding effect of class size on associations between object-oriented metrics and maintainability
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作者 卢红敏 周毓明 徐宝文 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期281-283,共3页
This paper uses three size metrics,which are collectable during the design phase,to analyze the potentially confounding effect of class size on the associations between object-oriented(OO)metrics and maintainability... This paper uses three size metrics,which are collectable during the design phase,to analyze the potentially confounding effect of class size on the associations between object-oriented(OO)metrics and maintainability.To draw as many general conclusions as possible,the confounding effect of class size is analyzed on 127 C++ systems and 113 Java systems.For each OO metric,the indirect effect that represents the distortion of the association caused by class size and its variance for individual systems is first computed.Then,a statistical meta-analysis technique is used to compute the average indirect effect over all the systems and to determine if it is significantly different from zero.The experimental results show that the confounding effects of class size on the associations between OO metrics and maintainability generally exist,regardless of whatever size metric is used.Therefore,empirical studies validating OO metrics on maintainability should consider class size as a confounding variable. 展开更多
关键词 object-oriented metrics VALIDATION class size CONFOUNDING MAINTAINABILITY
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PPP-ss-O@Rg3胶束冷冻干燥保护剂的选择
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作者 贾莉 张卫敏 马兰 《广州化工》 2025年第10期108-110,114,共4页
通过考察冷冻干燥保护剂种类及比例,筛选出了PPP-ss-O@Rg3胶束的冷冻干燥保护剂。实验测定胶束溶液冷冻干燥后的外观、再分散速度、粒径和包封率,考察了多种糖类单独及联合使用作对胶束冻干过程保护作用。结果表明,在外观和再分散速度方... 通过考察冷冻干燥保护剂种类及比例,筛选出了PPP-ss-O@Rg3胶束的冷冻干燥保护剂。实验测定胶束溶液冷冻干燥后的外观、再分散速度、粒径和包封率,考察了多种糖类单独及联合使用作对胶束冻干过程保护作用。结果表明,在外观和再分散速度方面,甘露醇在略显优势;在粒径和包封率方面,海藻糖效果较为理想。进一步研究确定甘露醇-海藻糖(3%+7%)二元体系可显著优化PPP-ss-O@Rg3冻干制剂的理化特性。本研究为开发稳定完整的PPP-ss-O@Rg3胶束递送系统提供了理论依据。 展开更多
关键词 冷冻干燥保护剂 甘露醇 海藻糖 PPP-ss-O@Rg3胶束
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Review of Remotely Sensed Imagery Classification Patterns Based on Object-oriented Image Analysis 被引量:9
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作者 LIU Yongxue LI Manchun +2 位作者 MAO Liang XU Feifei HUANG Shuo 《Chinese Geographical Science》 SCIE CSCD 2006年第3期282-288,共7页
With the wide use of high-resolution remotely sensed imagery, the object-oriented remotely sensed informa- tion classification pattern has been intensively studied. Starting with the definition of object-oriented remo... With the wide use of high-resolution remotely sensed imagery, the object-oriented remotely sensed informa- tion classification pattern has been intensively studied. Starting with the definition of object-oriented remotely sensed information classification pattern and a literature review of related research progress, this paper sums up 4 developing phases of object-oriented classification pattern during the past 20 years. Then, we discuss the three aspects of method- ology in detail, namely remotely sensed imagery segmentation, feature analysis and feature selection, and classification rule generation, through comparing them with remotely sensed information classification method based on per-pixel. At last, this paper presents several points that need to be paid attention to in the future studies on object-oriented RS in- formation classification pattern: 1) developing robust and highly effective image segmentation algorithm for multi-spectral RS imagery; 2) improving the feature-set including edge, spatial-adjacent and temporal characteristics; 3) discussing the classification rule generation classifier based on the decision tree; 4) presenting evaluation methods for classification result by object-oriented classification pattern. 展开更多
关键词 object-oriented image analysis remote sensing classification pattern
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假结核耶尔森氏菌T6SS效应蛋白TseN功能鉴定
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作者 任兆锐 刘永德 +7 位作者 顾亚洲 杨彦涛 汪宇迪 宋莉 李长富 朱玲芳 王瑶 沈锡辉 《微生物学通报》 北大核心 2025年第4期1491-1506,共16页
【背景】细菌六型分泌系统(type VI secretion system,T6SS)广泛分布于革兰氏阴性细菌,在细菌定殖、环境适应、细菌-宿主互作等过程中发挥重要作用;T6SS对致病菌假结核耶尔森氏菌(Yersinia pseudotuberculosis)的致病性有重要作用。【... 【背景】细菌六型分泌系统(type VI secretion system,T6SS)广泛分布于革兰氏阴性细菌,在细菌定殖、环境适应、细菌-宿主互作等过程中发挥重要作用;T6SS对致病菌假结核耶尔森氏菌(Yersinia pseudotuberculosis)的致病性有重要作用。【目的】探究假结核耶尔森氏菌T6SS基因簇编码的潜在效应蛋白T6SS分泌型效应核酸酶(T6SS secreted effector nuclease,TseN)的生理生化特性及其生物学功能。【方法】通过生物信息学分析锁定潜在的T6SS效应蛋白TseN及其免疫蛋白T6SS分泌型免疫核酸酶(T6SS secreted immune nuclease,TsiN);构建相关重组质粒转化大肠杆菌(Escherichia coli),利用生长曲线测定等方法探究TseN的细菌毒性及TsiN免疫活性;通过细菌双杂交试验验证TseN与TsiN的相互作用;纯化蛋白,通过体外DNA酶活实验明确TseN的DNA酶活特性;利用同源重组等技术构建假结核耶尔森氏菌tseN基因缺失菌株(ΔtseN),并构建回补菌株[ΔtseN(tseN)],确证TseN在细菌竞争、抵抗胁迫等方面的功能。【结果】表达TseN的大肠杆菌生长受到显著抑制,共表达TsiN的菌株生长恢复,并且TsiN通过与TseN直接相互作用来中和其毒性。TseN可以结合DNA,具有Mn2+依赖的DNA水解酶活性。相较于野生型菌株,ΔtseN介导细菌种内或种间竞争的能力显著减弱,并且ΔtseN的生物膜形成受到显著影响,面对高盐、低pH等胁迫条件时存活率显著降低,以上情况在回补菌株中得到一定恢复。【结论】TseN是假结核耶尔森氏菌T6SS分泌的Mn2+依赖的DNA水解酶,具有较强的细菌毒性作用;TsiN是其免疫蛋白,保护假结核耶尔森氏菌免受TseN的毒性作用。TseN介导假结核耶尔森氏菌参与细菌竞争,有助于其占据生态位。同时,能促进假结核耶尔森氏菌的生物膜形成、高盐和低pH等胁迫耐受能力。 展开更多
关键词 假结核耶尔森氏菌 T6ss 效应蛋白 免疫蛋白 功能鉴定
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线粒体靶向肽SS-31对炎症诱导髓核细胞衰老和焦亡的作用及机制研究
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作者 彭鑫 王志强 +3 位作者 张桐 杨光 吴小涛 高延征 《中国脊柱脊髓杂志》 北大核心 2025年第4期399-407,共9页
目的:探讨线粒体靶向肽SS-31对炎症诱导的髓核(nucleus pulposus,NP)细胞衰老、焦亡的作用及机制。方法:体外提取培养6周龄SD雄性大鼠的NP细胞,分为对照组、脂多糖(lipopolysaccharide,LPS)组和LPS+SS-31组,其中对照组不做处理,LPS组以... 目的:探讨线粒体靶向肽SS-31对炎症诱导的髓核(nucleus pulposus,NP)细胞衰老、焦亡的作用及机制。方法:体外提取培养6周龄SD雄性大鼠的NP细胞,分为对照组、脂多糖(lipopolysaccharide,LPS)组和LPS+SS-31组,其中对照组不做处理,LPS组以浓度为100μg/mL的LPS干预NP细胞24h,LPS+SS-31组在LPS干预前30min利用SS-31进行预处理。采用衰老相关β半乳糖苷酶(senescence associatedβ-galactosidase,SA-β-Gal)染色和Western blot(WB)实验评估各组细胞衰老及焦亡水平;采用透射电镜和氧耗率检测分析各组NP细胞线粒体功能;应用WB和免疫荧光检测各组磷酸化核因子-κB-p65(phosphorylated nuclear factor-κB-p65,p-NF-κB-p65)、环磷酸鸟苷-腺苷酸合成酶(cyclic GMP-AMP synthase,cGAS)和干扰素刺激基因(interferon stimulating gene,STING)的蛋白表达;苏木精-伊红(hematoxylin-eosin,HE)染色、免疫组化(immunohistochemistry,IHC)染色和WB实验分析体内注射SS-31对椎间盘退变、细胞衰老和焦亡的影响。结果:与LPS组相比,LPS+SS-31组的NP细胞SA-β-Gal染色阳性率、衰老标志蛋白(p53、p21)及焦亡相关分子(NLRP3、Caspase-1 p20)的表达均明显降低(P<0.05)。通过透射电镜观察发现LPS组NP细胞线粒体肿胀呈圆形,基质透亮,线粒体嵴间腔扩张;而LPS+SS-31组的线粒体肿胀明显消退,线粒体形态趋于正常。同时,与LPS组相比,LPS+SS-31组的NP细胞最大呼吸水平明显增强(P<0.05)。WB和免疫荧光检测结果显示,LPS干预明显上调了p-NF-κB-p65、cGAS和STING的表达(P<0.05),而SS-31的预处理显著抑制了LPS诱导的p-NF-κB-p65、cGAS和STING的表达(P<0.05)。体内实验证实局部注射SS-31可降低NP细胞衰老、焦亡,减轻纤维环穿刺诱导的椎间盘退变。结论:SS-31减轻了炎症诱导的NP细胞衰老和焦亡,这与其对NF-κB信号通路、cGAS/STING信号通路的抑制有关。 展开更多
关键词 ss-31 髓核细胞 炎症 衰老 焦亡
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Pine wilt disease detection in high-resolution UAV images using object-oriented classification 被引量:3
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作者 Zhao Sun Yifu Wang +4 位作者 Lei Pan Yunhong Xie Bo Zhang Ruiting Liang Yujun Sun 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第4期1377-1389,共13页
Pine wilt disease(PWD)is currently one of the main causes of large-scale forest destruction.To control the spread of PWD,it is essential to detect affected pine trees quickly.This study investigated the feasibility of... Pine wilt disease(PWD)is currently one of the main causes of large-scale forest destruction.To control the spread of PWD,it is essential to detect affected pine trees quickly.This study investigated the feasibility of using the object-oriented multi-scale segmentation algorithm to identify trees discolored by PWD.We used an unmanned aerial vehicle(UAV)platform equipped with an RGB digital camera to obtain high spatial resolution images,and multiscale segmentation was applied to delineate the tree crown,coupling the use of object-oriented classification to classify trees discolored by PWD.Then,the optimal segmentation scale was implemented using the estimation of scale parameter(ESP2)plug-in.The feature space of the segmentation results was optimized,and appropriate features were selected for classification.The results showed that the optimal scale,shape,and compactness values of the tree crown segmentation algorithm were 56,0.5,and 0.8,respectively.The producer’s accuracy(PA),user’s accuracy(UA),and F1 score were 0.722,0.605,and 0.658,respectively.There were no significant classification errors in the final classification results,and the low accuracy was attributed to the low number of objects count caused by incorrect segmentation.The multi-scale segmentation and object-oriented classification method could accurately identify trees discolored by PWD with a straightforward and rapid processing.This study provides a technical method for monitoring the occurrence of PWD and identifying the discolored trees of disease using UAV-based high-resolution images. 展开更多
关键词 object-oriented classification Multi-scale segmentation UAV images Pine wilt disease
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An Edge-assisted, Object-oriented Random Forest Approach for Refined Extraction of Tea Plantations Using Multi-temporal Sentinel-2 and High-resolution Gaofen-2 Imagery 被引量:3
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作者 Juanjuan YU Xiufeng HE +4 位作者 Jia XU Zhuang GAO Peng YANG Yuanyuan CHEN Jiacheng XIONG 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第1期31-46,共16页
As a consumed and influential natural plant beverage,tea is widely planted in subtropical and tropical areas all over the world.Affected by(sub)tropical climate characteristics,the underlying surface of the tea distri... As a consumed and influential natural plant beverage,tea is widely planted in subtropical and tropical areas all over the world.Affected by(sub)tropical climate characteristics,the underlying surface of the tea distribution area is extremely complex,with a variety of vegetation types.In addition,tea distribution is scattered and fragmentized in most of China.Therefore,it is difficult to obtain accurate tea information based on coarse resolution remote sensing data and existing feature extraction methods.This study proposed a boundary-enhanced,object-oriented random forest method on the basis of high-resolution GF-2 and multi-temporal Sentinel-2 data.This method uses multispectral indexes,textures,vegetable indices,and variation characteristics of time-series NDVI from the multi-temporal Sentinel-2 imageries to obtain abundant features related to the growth of tea plantations.To reduce feature redundancy and computation time,the feature elimination algorithm based on Mean Decrease Accuracy(MDA)was used to generate the optimal feature set.Considering the serious boundary inconsistency problem caused by the complex and fragmented land cover types,high resolution GF-2 image was segmented based on the MultiResolution Segmentation(MRS)algorithm to assist the segmentation of Sentinel-2,which contributes to delineating meaningful objects and enhancing the reliability of the boundary for tea plantations.Finally,the object-oriented random forest method was utilized to extract the tea information based on the optimal feature combination in the Jingmai Mountain,Yunnan Province.The resulting tea plantation map had high accuracy,with a 95.38%overall accuracy and 0.91 kappa coefficient.We conclude that the proposed method is effective for mapping tea plantations in high heterogeneity mountainous areas and has the potential for mapping tea plantations in large areas. 展开更多
关键词 tea plantation mapping MULTI-TEMPORAL edge-assisted object-oriented random forest Sentinel-2 Gaofen-2
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Double Polarization SAR Image Classification based on Object-Oriented Technology 被引量:2
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作者 Xiuguo Liu Yongsheng Li +1 位作者 Wei Gao Lin Xiao 《Journal of Geographic Information System》 2010年第2期113-119,共7页
This paper proposed to use double polarization synthetic aperture radar (SAR) image to classify surface feature, based on DEM. It takes fully use of the polarization information and external information. This pa-per u... This paper proposed to use double polarization synthetic aperture radar (SAR) image to classify surface feature, based on DEM. It takes fully use of the polarization information and external information. This pa-per utilizes ENVISAT ASAR APP double-polarization data of Poyang lake area in Jiangxi Province. Com-pared with traditional pixel-based classification, this paper fully uses object features (color, shape, hierarchy) and accessorial DEM information. The classification accuracy improves from the original 73.7% to 91.84%. The result shows that object-oriented classification technology is suitable for double polarization SAR’s high precision classification. 展开更多
关键词 SYNTHETIC APERTURE RADAR Image Classification object-oriented Pixel-Based DEM
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基于CRISPR/Cas9技术的SS18-SSX1阳性细胞模型的构建与验证
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作者 田娇 张乾儒 +4 位作者 王宁 史奇 李亚 张琨岚 李锋 《石河子大学学报(自然科学版)》 北大核心 2025年第1期8-15,共8页
目的 利用CRISPR/Cas9技术构建并验证SS18-SSX1^(+)-HEK293T细胞模型。方法 靶向SS18和SSX1分别设计sgRNA,构建Lentivirus-CRISPR v2-SS18-gRNA-SSX1-gRNA-EGFP一体化慢病毒载体,通过慢病毒转染和荧光流式分选技术筛选转入载体的HEK293... 目的 利用CRISPR/Cas9技术构建并验证SS18-SSX1^(+)-HEK293T细胞模型。方法 靶向SS18和SSX1分别设计sgRNA,构建Lentivirus-CRISPR v2-SS18-gRNA-SSX1-gRNA-EGFP一体化慢病毒载体,通过慢病毒转染和荧光流式分选技术筛选转入载体的HEK293T多克隆细胞,在多克隆细胞的基础上挑选SS18-SSX1阳性的单克隆细胞株,通过RT-PCR、Sanger测序和Western Blot验证SS18-SSX1^(+)-HEK293T单克隆细胞系构建成功。结果 成功构建了Lentivirus-CRISPR v2-SS18-gRNA-SSX1-gRNA-EGFP慢病毒载体;通过RT-PCR、Sanger测序和WB实验在178个HEK293T单克隆细胞中成功筛选并验证出1株SS18-SSX1阳性的单克隆细胞系。结论 利用CRISPR/Cas9技术成功构建SS18-SSX1融合基因阳性的HEK293T细胞系。 展开更多
关键词 CRISPR/Cas9 滑膜肉瘤 ss18-ssX1 HEK293T细胞
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Predicting the fault-proneness of class hierarchy in object-oriented software using a layered kernel 被引量:1
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作者 Peng HUANG Jie ZHU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第10期1390-1397,共8页
A novel kernel learning method for object-oriented (00) software fault prediction is proposed in this paper. With this method, each set of classes that has inheritance relation named class hierarchy, is treated as a... A novel kernel learning method for object-oriented (00) software fault prediction is proposed in this paper. With this method, each set of classes that has inheritance relation named class hierarchy, is treated as an elemental software model. A layered kernel is introduced to handle the tree data structure corresponding to the class hierarchy models. This method was vali- dated using both an artificial dataset and a case of industrial software from the optical communication field. Preliminary experi- ments showed that our approach is very effective in learning structured data and outperforms the traditional support vector learning methods in accurately and correctly predicting the fault-prone class hierarchy model in real-life OO software. 展开更多
关键词 object-oriented software Fault-proneness Support vector machine Structured kernel
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Research on the Classification of High Resolution Image Based on Object-Oriented and Class Rule 被引量:1
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作者 Li Chaokui Fang Jun +1 位作者 Wu Baiyan Chen Jianhui 《Journal of Earth Science and Engineering》 2018年第1期31-38,共8页
With the development of remote sensing technology,the spatial resolution,spectral resolution and time resolution of remote sensing data are greatly improved.How to efficiently process and interpret the massive high re... With the development of remote sensing technology,the spatial resolution,spectral resolution and time resolution of remote sensing data are greatly improved.How to efficiently process and interpret the massive high resolution remote sensing image data for ground objects,which are of spatial geometry and texture information,has become the focus and key issue in the field of remote sensing research.A new method of the classification(OCRC(object-oriented and class rule classification))of remote sensing,which is of object-oriented and rule,has been presented in this paper,that is,through the discovery and mining the knowledge of spectrum and spatial characteristics of high-resolution remote sensing image,establish a multi-level network image object segmentation and classification structure of remote sensing image to achieve classification and accuracy assessment accurately and quickly for ground targets.Selected the worldview-2 image data in the Zangnan area as a study object,using the OCRC to verify the experiment which was a combination of the mean variance method,the maximum area method and the accuracy comparison to analysis selected three kinds of optimal segmentation scale and established a multi-level image object network hierarchy for image classification experiments.The results show that the OCRC can enable the high resolution image classification results similar to the visual interpretation of the results,and has higher classification accuracy.The overall accuracy and Kappa coefficient of the object-oriented rule classification method are 97.38%,0.9673;compared with object-oriented SVM method,respectively higher than 6.23%,0.078;compared with object-oriented KNN method,respectively more than 7.96%,0.0996.The extraction precision and user accuracy of the buildings compared with object-oriented SVM method,respectively higher than 18.39%,3.98%,respectively better than the object-oriented KNN(K-Nearest Neighbor)method 21.27%,14.97%. 展开更多
关键词 object-oriented RULES high resolution multi-scale segmentation.
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尿素变性PAGE中ssDNA回收方法的研究与优化
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作者 郑楚君 黄海轩 +3 位作者 王雨萱 叶煜玮 徐斐 袁敏 《工业微生物》 2025年第1期110-115,124,共7页
从变性PAGE中获得高纯度、高回收率的ss DNA,是功能核酸研究及适配体筛选的关键环节之一。文章采用直取法、改良煮沸法、试剂盒回收和正丁醇回收4种方法,在尿素变性PAGE中对ss DNA进行了提取回收研究,并发现改良煮沸法的ss DNA回收效率... 从变性PAGE中获得高纯度、高回收率的ss DNA,是功能核酸研究及适配体筛选的关键环节之一。文章采用直取法、改良煮沸法、试剂盒回收和正丁醇回收4种方法,在尿素变性PAGE中对ss DNA进行了提取回收研究,并发现改良煮沸法的ss DNA回收效率显著优于其他3种回收方法。对实验条件作进一步优化,使ss DNA回收效率达到了70.33±0.35%,并获得了较高的回收纯度(A260/A280=1.85)。可见,该种方法操作简便、回收速度快,且不易受有机试剂的干扰,同时成本低廉,单次回收成本不足1元,在功能核酸的筛选及回收利用方面具有良好的实际应用前景。 展开更多
关键词 尿素变性PAGE ss DNA回收 改良煮沸法
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Object-oriented crop classification based on UAV remote sensing imagery 被引量:1
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作者 ZHANG Lan ZHANG Yanhong 《Global Geology》 2022年第1期60-68,共9页
UAV remote sensing images have the advantages of high spatial resolution,fast speed,strong real-time performance,and convenient operation,etc.,and have become a recently developed,vital means of acquiring surface info... UAV remote sensing images have the advantages of high spatial resolution,fast speed,strong real-time performance,and convenient operation,etc.,and have become a recently developed,vital means of acquiring surface information.It is an important research task for precision agriculture to make full use of the spectrum,texture,color and other characteristic information of crops,especially the spatial arrangement and structure information of features,to explore effective methods for the classification of multiple varieties of crops.In order to explore the applicability of the object-oriented method to achieve accurate classification of UAV high-resolution images,the paper used the object-oriented classification method in ENVI to classify the UAV high-resolution remote sensing image obtained from the orderly structured 28 species of crops in the test field,which mainly includes image segmentation and object classification.The results showed that the plots obtained after classification were continuous and complete,basically in line with the actual situation,and the overall accuracy of crop classification was 91.73%,with Kappa coefficient of 0.87.Compared with the crop planting area based on remote sensing interpretation and field survey,the area error of 17 species of crops in this study was controlled within 15%,which provides a basis for object-oriented crop classification of UAV remote sensing images. 展开更多
关键词 object-oriented classification UAV remote sensing imagery crop classification
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含硫气井P110SS油管酸化-返排-生产全服役周期腐蚀特性的研究
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作者 罗伟 郭丽雪 +3 位作者 艾志鹏 侯铎 吴旭 张智 《材料保护》 2025年第10期157-167,共11页
为了明确四川盆地某含硫气井中P110SS油管在全服役周期连续多环境中的腐蚀损伤行为,利用高温高压釜模拟测试P110SS油管连续经历酸化压裂-残酸返排-生产工况的腐蚀特性。采用SEM、EDS、XRD和3D光学显微镜观察等方法分析了P110SS油管的腐... 为了明确四川盆地某含硫气井中P110SS油管在全服役周期连续多环境中的腐蚀损伤行为,利用高温高压釜模拟测试P110SS油管连续经历酸化压裂-残酸返排-生产工况的腐蚀特性。采用SEM、EDS、XRD和3D光学显微镜观察等方法分析了P110SS油管的腐蚀损伤特性,并对局部腐蚀坑尺寸进行了测量。结果表明:酸压工况下气相环境中的腐蚀速率为12.57 g/(m^(2)·h),远大于液相环境中的腐蚀速率2.06 g/(m^(2)·h),因此需要重点关注酸化压裂施工闷井阶段,在酸液面以上位置管柱的腐蚀损伤风险;连续经历多个工况下,P110SS油管在气相和液相腐蚀介质环境中的腐蚀速率为v_(鲜酸)>v_(鲜酸+残酸)>v_(鲜酸+残酸+地层水);鲜酸在140℃高温环境下缓蚀剂的效果良好,但在残酸返排工况中由于失去缓蚀剂的保护作用,管材出现严重点蚀;随着连续腐蚀工况的叠加,P110SS在气相和液相环境中的局部腐蚀都进一步加重。 展开更多
关键词 含硫气井 P110ss油管 全服役周期 腐蚀损伤
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SS-LMS自适应均衡算法的CTLE设计
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作者 唐明华 尤浩龙 +2 位作者 李刚 赵珍阳 陈建军 《国防科技大学学报》 北大核心 2025年第1期190-197,共8页
随着先进工艺和技术的不断进步,要想保证数据在高速传输中的正确性,均衡器需要有更高的补偿和更低的功耗,才能实现高效通信。基于12 nm互补金属氧化物半导体工艺,设计了一种高增益、低功耗的自适应连续时间线性均衡器(continuous time l... 随着先进工艺和技术的不断进步,要想保证数据在高速传输中的正确性,均衡器需要有更高的补偿和更低的功耗,才能实现高效通信。基于12 nm互补金属氧化物半导体工艺,设计了一种高增益、低功耗的自适应连续时间线性均衡器(continuous time linear equalizer,CTLE),该均衡器采用2级级联结构来补偿信道衰减,并提高接收信号的质量。此外,自适应模块通过采用符号-符号最小均方误差(sign-sign least mean square,SS-LMS)算法,使抽头系数加快了收敛速度。仿真结果表明,当传输速率为16 Gbit/s时,均衡器可以补偿-15.53 dB的半波特率通道衰减,均衡器系数在16×10^(4)个单元间隔数据内收敛,并且收敛之后接收误码率低于10^(-12)。 展开更多
关键词 连续时间线性均衡器 自适应 符号-符号最小均方误差算法
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“数字资本”何以影响学生的创造性——基于SSES2023的数据分析
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作者 张红 唐汉卫 +1 位作者 张珈瑜泽 李媛媛 《中国电化教育》 北大核心 2025年第5期53-60,94,共9页
创造性是大国竞争的关键。数字时代,数字资本对创造性的影响不容忽视,但其影响机理有待进一步揭示。该研究以参与SSES 2023调查的7648名中国学生为调查对象,采用OLS回归、Shapley值分解和分位数回归模型探究数字资源与数字能力所组成的... 创造性是大国竞争的关键。数字时代,数字资本对创造性的影响不容忽视,但其影响机理有待进一步揭示。该研究以参与SSES 2023调查的7648名中国学生为调查对象,采用OLS回归、Shapley值分解和分位数回归模型探究数字资源与数字能力所组成的数字资本对学生创造性的影响。研究发现:台式电脑、手提电脑/笔记本电脑、平板电脑和电子阅读器等数字资源均会对学生的创造性发展产生显著的正向影响,其中电子阅读器的影响效应最大;数字能力比数字资源更能促进学生创造性的提升,对学生创造性的贡献率可达28%;平板电脑和电子阅读器的持有量对学生创造性的提升呈现出边际效应递增作用,而手机持有量则对学生创造性的提升呈现出边际效应递减作用;数字能力的提升对高水平创造性的学生影响效益更大。研究建议:弥合数字资本鸿沟,推动学生创造性公平发展;优化数字资源配置,为学生创造性发展提供针对性支持;强化数字能力建设,促进数字资源向创造性高效转化;规避手机过度使用,多举措科学引导学生创造性发展。 展开更多
关键词 数字资本 创造性 ssES2023 分位数回归
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国际社会与情感能力测评的新进展与新趋向——基于OECD两轮SSES的经验与展望
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作者 唐一鹏 《中国考试》 北大核心 2025年第5期73-83,共11页
OECD社会与情感能力调查(SSES)已成功开展两轮测评,在国际社会引起较大反响。从两轮测评的实施比较来看,SSES在主题上从单向度的学习转向了多向度的幸福生活,参与国家数量不断增多,测评方法回归到学生自我汇报,测评题项更加丰富。对SSE... OECD社会与情感能力调查(SSES)已成功开展两轮测评,在国际社会引起较大反响。从两轮测评的实施比较来看,SSES在主题上从单向度的学习转向了多向度的幸福生活,参与国家数量不断增多,测评方法回归到学生自我汇报,测评题项更加丰富。对SSES的趋势数据进行国际比较分析发现,我国参与测评的小学生普遍表现良好,尤其在任务能力和协作能力两个维度上均名列国际前茅;我国中学生的表现大多处于中等水平,虽然在协作能力维度上表现较为突出,但在活力与好奇心上的表现存在明显不足。未来SSES将从概念框架、智能技术运用和教育实践三个方面寻求新的突破。我国的社会与情感能力测评研究尚处于起步阶段,SSES的经验具有重要借鉴价值。 展开更多
关键词 OECD ssES 社会与情感能力 国际测评 教育评价
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