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Optimised CNN Architectures for Handwritten Arabic Character Recognition
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作者 Salah Alghyaline 《Computers, Materials & Continua》 SCIE EI 2024年第6期4905-4924,共20页
Handwritten character recognition is considered challenging compared with machine-printed characters due to the different human writing styles.Arabic is morphologically rich,and its characters have a high similarity.T... Handwritten character recognition is considered challenging compared with machine-printed characters due to the different human writing styles.Arabic is morphologically rich,and its characters have a high similarity.The Arabic language includes 28 characters.Each character has up to four shapes according to its location in the word(at the beginning,middle,end,and isolated).This paper proposed 12 CNN architectures for recognizing handwritten Arabic characters.The proposed architectures were derived from the popular CNN architectures,such as VGG,ResNet,and Inception,to make them applicable to recognizing character-size images.The experimental results on three well-known datasets showed that the proposed architectures significantly enhanced the recognition rate compared to the baseline models.The experiments showed that data augmentation improved the models’accuracies on all tested datasets.The proposed model outperformed most of the existing approaches.The best achieved results were 93.05%,98.30%,and 96.88%on the HIJJA,AHCD,and AIA9K datasets. 展开更多
关键词 Optical character recognition(OCR) handwritten arabic characters deep learning
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Chronic hepatitis B virus infection in Eastern Ethiopia:Clinical characteristics and determinants of cirrhosis 被引量:3
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作者 Nejib Y Ismael Semir A Usmael +3 位作者 Nega B Belay Hailemichael Desalegn Mekonen Asgeir Johannessen Stian MS Orlien 《World Journal of Hepatology》 2024年第7期995-1008,共14页
BACKGROUND Chronic hepatitis B(CHB)virus infection is a major cause of liver-associated morbidity and mortality,particularly in low-income countries.A better understanding of the epidemiological,clinical,and virologic... BACKGROUND Chronic hepatitis B(CHB)virus infection is a major cause of liver-associated morbidity and mortality,particularly in low-income countries.A better understanding of the epidemiological,clinical,and virological characteristics of CHB will guide appropriate treatment strategies and improve the control and management of CHB in Ethiopia.AIM To investigate the characteristics of CHB in Eastern Ethiopia and assess the efficacy and safety of antiviral treatment.METHODS This cohort study included 193 adults who were human immunodeficiency virus-negative with CHB between June 2016 and December 2019.Baseline assessments included chemistry,serologic,and viral markers.χ^(2) tests,Mann-Whitney U tests,and logistic regression analyses were used to identify the determinants of cirrhosis.Tenofovir disoproxil fumarate(TDF)was initiated using treatment criteria from the Ethiopian CHB pilot program.RESULTS A total of 132 patients(68.4%)were men,with a median age of 30 years[interquartile range(IQR):24-38].At enrollment,60(31.1%)patients had cirrhosis,of whom 35(58.3%)had decompensated cirrhosis.Khat use,hepatitis B envelope antigen positivity,and a high viral load were independently associated with cirrhosis.Additionally,66 patients(33.4%)fulfilled the treatment criteria and 59(30.6%)started TDF.Among 29 patients who completed 24 months of treatment,the median aspartate aminotransferase to platelet ratio index declined from 1.54(IQR:0.66-2.91)to 1.10(IQR:0.75-2.53)(P=0.002),and viral suppression was achieved in 80.9%and 100%of patients after 12 months and 24 months of treatment,respectively.Among the treated patients,12(20.3%)died within the first 6 months of treatment,of whom 8 had decompensated cirrhosis.CONCLUSION This study highlights the high prevalence of cirrhosis,initial mortality,and the efficacy of TDF treatment.Scaling up measures to prevent and control CHB infections in Ethiopia is crucial. 展开更多
关键词 Chronic hepatitis b CIRRHOSIS Cohort study Resource-limited settings Sub-Saharan Africa
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Effect of Co on Solidification Characteristics and Microstructural Transformation of Non-equilibrium Solidified Cu-Ni Alloys
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作者 安红恩 Bih-Lii Chua +1 位作者 Ismail Saad Willey Yun Hsien Liew 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期444-453,共10页
Non-equilibrium solidification structures of Cu55Ni45 and Cu55Ni43Co2 alloys were prepared by the molten glass purification cycle superheating method.The variation of the recalescence phenomenon with the degree of und... Non-equilibrium solidification structures of Cu55Ni45 and Cu55Ni43Co2 alloys were prepared by the molten glass purification cycle superheating method.The variation of the recalescence phenomenon with the degree of undercooling in the rapid solidification process was investigated using an infrared thermometer.The addition of the Co element affected the evolution of the recalescence phenomenon in Cu-Ni alloys.The images of the solid-liquid interface migration during the rapid solidification of supercooled melts were captured by using a high-speed camera.The solidification rate of Cu-Ni alloys,with the addition of Co elements,was explored.Finally,the grain refinement structure with low supercooling was characterised using electron backscatter diffraction(EBSD).The effect of Co on the microstructural evolution during nonequilibrium solidification of Cu-Ni alloys under conditions of small supercooling is investigated by comparing the microstructures of Cu55Ni45 and Cu55Ni43Co2 alloys.The experimental results show that the addition of a small amount of Co weakens the recalescence behaviour of the Cu55Ni45 alloy and significantly reduces the thermal strain in the rapid solidification phase.In the rapid solidification phase,the thermal strain is greatly reduced,and there is a significant increase in the characteristic undercooling degree.Furthermore,the addition of Co and the reduction of Cu not only result in a lower solidification rate of the alloy,but also contribute to the homogenisation of the grain size. 展开更多
关键词 non-equilibrium solidification recalescence effect solidification character microstructure
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A Method for Detecting and Recognizing Yi Character Based on Deep Learning
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作者 Haipeng Sun Xueyan Ding +2 位作者 Jian Sun HuaYu Jianxin Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第2期2721-2739,共19页
Aiming at the challenges associated with the absence of a labeled dataset for Yi characters and the complexity of Yi character detection and recognition,we present a deep learning-based approach for Yi character detec... Aiming at the challenges associated with the absence of a labeled dataset for Yi characters and the complexity of Yi character detection and recognition,we present a deep learning-based approach for Yi character detection and recognition.In the detection stage,an improved Differentiable Binarization Network(DBNet)framework is introduced to detect Yi characters,in which the Omni-dimensional Dynamic Convolution(ODConv)is combined with the ResNet-18 feature extraction module to obtain multi-dimensional complementary features,thereby improving the accuracy of Yi character detection.Then,the feature pyramid network fusion module is used to further extract Yi character image features,improving target recognition at different scales.Further,the previously generated feature map is passed through a head network to produce two maps:a probability map and an adaptive threshold map of the same size as the original map.These maps are then subjected to a differentiable binarization process,resulting in an approximate binarization map.This map helps to identify the boundaries of the text boxes.Finally,the text detection box is generated after the post-processing stage.In the recognition stage,an improved lightweight MobileNetV3 framework is used to recognize the detect character regions,where the original Squeeze-and-Excitation(SE)block is replaced by the efficient Shuffle Attention(SA)that integrates spatial and channel attention,improving the accuracy of Yi characters recognition.Meanwhile,the use of depth separable convolution and reversible residual structure can reduce the number of parameters and computation of the model,so that the model can better understand the contextual information and improve the accuracy of text recognition.The experimental results illustrate that the proposed method achieves good results in detecting and recognizing Yi characters,with detection and recognition accuracy rates of 97.5%and 96.8%,respectively.And also,we have compared the detection and recognition algorithms proposed in this paper with other typical algorithms.In these comparisons,the proposed model achieves better detection and recognition results with a certain reliability. 展开更多
关键词 Yi characters text detection text recognition attention mechanism deep neural network
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Fireworks Optimization with Deep Learning-Based Arabic Handwritten Characters Recognition Model
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作者 Abdelwahed Motwakel Badriyya B.Al-onazi +5 位作者 Jaber S.Alzahrani Ayman Yafoz Mahmoud Othman Abu Sarwar Zamani Ishfaq Yaseen Amgad Atta Abdelmageed 《Computer Systems Science & Engineering》 2024年第5期1387-1403,共17页
Handwritten character recognition becomes one of the challenging research matters.More studies were presented for recognizing letters of various languages.The availability of Arabic handwritten characters databases wa... Handwritten character recognition becomes one of the challenging research matters.More studies were presented for recognizing letters of various languages.The availability of Arabic handwritten characters databases was confined.Almost a quarter of a billion people worldwide write and speak Arabic.More historical books and files indicate a vital data set for many Arab nationswritten in Arabic.Recently,Arabic handwritten character recognition(AHCR)has grabbed the attention and has become a difficult topic for pattern recognition and computer vision(CV).Therefore,this study develops fireworks optimizationwith the deep learning-based AHCR(FWODL-AHCR)technique.Themajor intention of the FWODL-AHCR technique is to recognize the distinct handwritten characters in the Arabic language.It initially pre-processes the handwritten images to improve their quality of them.Then,the RetinaNet-based deep convolutional neural network is applied as a feature extractor to produce feature vectors.Next,the deep echo state network(DESN)model is utilized to classify handwritten characters.Finally,the FWO algorithm is exploited as a hyperparameter tuning strategy to boost recognition performance.Various simulations in series were performed to exhibit the enhanced performance of the FWODL-AHCR technique.The comparison study portrayed the supremacy of the FWODL-AHCR technique over other approaches,with 99.91%and 98.94%on Hijja and AHCD datasets,respectively. 展开更多
关键词 Arabic language handwritten character recognition deep learning CLASSIFICATION parameter tuning
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Audio2AB:Audio-driven collaborative generation of virtual character animation
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作者 Lichao NIU Wenjun XIE +2 位作者 Dong WANG Zhongrui CAO Xiaoping LIU 《虚拟现实与智能硬件(中英文)》 EI 2024年第1期56-70,共15页
Background Considerable research has been conducted in the areas of audio-driven virtual character gestures and facial animation with some degree of success.However,few methods exist for generating full-body animation... Background Considerable research has been conducted in the areas of audio-driven virtual character gestures and facial animation with some degree of success.However,few methods exist for generating full-body animations,and the portability of virtual character gestures and facial animations has not received sufficient attention.Methods Therefore,we propose a deep-learning-based audio-to-animation-and-blendshape(Audio2AB)network that generates gesture animations and ARK it's 52 facial expression parameter blendshape weights based on audio,audio-corresponding text,emotion labels,and semantic relevance labels to generate parametric data for full-body animations.This parameterization method can be used to drive full-body animations of virtual characters and improve their portability.In the experiment,we first downsampled the gesture and facial data to achieve the same temporal resolution for the input,output,and facial data.The Audio2AB network then encoded the audio,audio-corresponding text,emotion labels,and semantic relevance labels,and then fused the text,emotion labels,and semantic relevance labels into the audio to obtain better audio features.Finally,we established links between the body,gestures,and facial decoders and generated the corresponding animation sequences through our proposed GAN-GF loss function.Results By using audio,audio-corresponding text,and emotional and semantic relevance labels as input,the trained Audio2AB network could generate gesture animation data containing blendshape weights.Therefore,different 3D virtual character animations could be created through parameterization.Conclusions The experimental results showed that the proposed method could generate significant gestures and facial animations. 展开更多
关键词 Audio-driven Virtual character Full-body animation Audio2Ab blendshape GAN-GF
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A Novel 6G Scalable Blockchain Clustering-Based Computer Vision Character Detection for Mobile Images
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作者 Yuejie Li Shijun Li 《Computers, Materials & Continua》 SCIE EI 2024年第3期3041-3070,共30页
6G is envisioned as the next generation of wireless communication technology,promising unprecedented data speeds,ultra-low Latency,and ubiquitous Connectivity.In tandem with these advancements,blockchain technology is... 6G is envisioned as the next generation of wireless communication technology,promising unprecedented data speeds,ultra-low Latency,and ubiquitous Connectivity.In tandem with these advancements,blockchain technology is leveraged to enhance computer vision applications’security,trustworthiness,and transparency.With the widespread use of mobile devices equipped with cameras,the ability to capture and recognize Chinese characters in natural scenes has become increasingly important.Blockchain can facilitate privacy-preserving mechanisms in applications where privacy is paramount,such as facial recognition or personal healthcare monitoring.Users can control their visual data and grant or revoke access as needed.Recognizing Chinese characters from images can provide convenience in various aspects of people’s lives.However,traditional Chinese character text recognition methods often need higher accuracy,leading to recognition failures or incorrect character identification.In contrast,computer vision technologies have significantly improved image recognition accuracy.This paper proposed a Secure end-to-end recognition system(SE2ERS)for Chinese characters in natural scenes based on convolutional neural networks(CNN)using 6G technology.The proposed SE2ERS model uses the Weighted Hyperbolic Curve Cryptograph(WHCC)of the secure data transmission in the 6G network with the blockchain model.The data transmission within the computer vision system,with a 6G gradient directional histogram(GDH),is employed for character estimation.With the deployment of WHCC and GDH in the constructed SE2ERS model,secure communication is achieved for the data transmission with the 6G network.The proposed SE2ERS compares the performance of traditional Chinese text recognition methods and data transmission environment with 6G communication.Experimental results demonstrate that SE2ERS achieves an average recognition accuracy of 88%for simple Chinese characters,compared to 81.2%with traditional methods.For complex Chinese characters,the average recognition accuracy improves to 84.4%with our system,compared to 72.8%with traditional methods.Additionally,deploying the WHCC model improves data security with the increased data encryption rate complexity of∼12&higher than the traditional techniques. 展开更多
关键词 6G technology blockchain end-to-end recognition Chinese characters natural scene computer vision algorithms convolutional neural network
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Chip Surface Character Recognition Based on OpenCV
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作者 Lihang Yin 《Journal of Electronic Research and Application》 2024年第4期161-167,共7页
Chip surface character recognition is an important part of quality inspection in the field of microelectronics manufacturing.By recognizing the character information on the chip,automated production,quality control,an... Chip surface character recognition is an important part of quality inspection in the field of microelectronics manufacturing.By recognizing the character information on the chip,automated production,quality control,and data collection and analysis can be achieved.This article studies a chip surface character recognition method based on the OpenCV vision library.Firstly,the obtained chip images are preprocessed.Secondly,the template matching method is used to locate the chip position.In addition,the surface characters on the chip are individually segmented,and each character image is extracted separately.Finally,a Support Vector Machine(SVM)is used to classify and recognize characters.The results show that this method can accurately recognize the surface characters of chips and meet the requirements of chip quality inspection. 展开更多
关键词 Template matching character recognition SVM OPENCV
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Epidemiological and Subtype Characterization of Influenza Viruses Infection in Children in Shenzhen, China during Three Consecutive Seasons (January 2016-December 2018)
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作者 Yaxian Kuang Ruihong Ma +3 位作者 Lei Jia Qiang Yao Chenhui Zhang Xiaoying Fu 《Open Journal of Pediatrics》 2024年第5期851-864,共14页
Background: Children with seasonal influenza infection cause a significant burden of disease each year in the pediatric clinic. Influenza A and B viruses are the major types responsible for illness. A better understan... Background: Children with seasonal influenza infection cause a significant burden of disease each year in the pediatric clinic. Influenza A and B viruses are the major types responsible for illness. A better understanding of the periodicity facilitates the prevention and control of influenza in children. Objective: This study aims to analyze the epidemiological patterns and subtype characterization of influenza viruses among children in Shenzhen, China. Methods: Influenza samples were collected by nasopharyngeal swabs from influenza like illness patients in Shenzhen Children’s Hospital from January 2016 to December 2018. The positive cases and influenza subtypes were determined by gold labeled antigen detection and reverse transcriptase polymerase chain reaction. The influenza periodicity and age, subtype distribution as well as the association between climate parameters and different influenza subtypes were analyzed by SPSS 22.0. Results: The influenza positive rate during 2016-2018 was 21.0%, with a highest positive rate in the year 2018. The positive rate varied by month, season, and year describing a sequence of peaks presenting primarily in all year including spring, summer and winter. The characteristics of influenza peak were different in each year, with a spring peak in 2016 and a summer plus a winter-spring peaks in 2017 and 2018. In addition, influenza B exhibited a winter-spring seasonal pattern while influenza A displayed a more variable seasonality, highlighting influenza B rather than influenza A which had a negative association with climate parameters. Influenza-positive cases were older than influenza-negative cases (P P Conclusion: Influenza activity in children from Shenzhen typically displays both winter-spring and summer peaks. Influenza A epidemic occurred separately or co-circulated with influenza B, with a winter-spring pattern for influenza B and a much more variable seasonality for influenza A. Influenza B had a negative association with climate parameters. In addition, hospitalization with influenza often occurs in younger individuals infected with influenza A. 展开更多
关键词 INFLUENZA Influenza Like Illness Gold Labeled Antigen Detection Reverse Transcriptase Polymerase Chain Reaction Influenza A Influenza b
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Genetic and Correlation Analysis of Grain Characters in Three-line Hybrid Rice 被引量:11
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作者 邹小云 邓辉明 +6 位作者 傅军如 彭小松 朱昌兰 贺晓鹏 陈小荣 贺浩华 刘宜柏 《Agricultural Science & Technology》 CAS 2009年第2期77-81,共5页
Abst[Objective] This study was to understand the genetic dynamics of three-line hybrid rice, and explore the respective effect of sterile line and restoring line on grain characters of hybrid rica. [Method] Four three... Abst[Objective] This study was to understand the genetic dynamics of three-line hybrid rice, and explore the respective effect of sterile line and restoring line on grain characters of hybrid rica. [Method] Four three-line stedle lines and 27 restoring lines(cultivars) commonly culti- vated in Central China region were regarded as expadmental materials to conduct 4 x27NCII cross design, and the grain characters of three-line hybrid rico were analyzed at genetic and correlation levels. [ Result] Four characters of grain length, grain width, 1 000-grain weight and length- width ratio play the leading role in additive gene effect; these four characters were simultaneously influenced by male parent and female parent, but the effect from male parent was relatively larger. The grain length, grain width, 1 000-grain weight and length-width ratio all have high brood hedtabUities( respectively 99.65%, 98.31%, 95.27% and 98.81% ). Correlation analysis showed that grain length was positively correlated with 1 000-grain weight and length-width ratio at extremely significant level; 1 000-grain weight was positively correlated with grain length and length- width ratio at extremely significant level, and was insignificantly correlated with grain width; grain width was negatively correlated with grain length and length-width ratio at extremely significant level. Path analysis showed that the direct path coefficients of grain length, grain width and 1 0(30- grain weight to length-width ratio were 0.624 6, -0.555 9 and -0.015 8, respectively. [ Conclusion] This study systematically analyzed the effects of stedle line and restoring line on grain characters of hybrid rice, which provided theoretical basis for breeding high quality and yield hy- brid dce. 展开更多
关键词 Three-line hybrid dce Grain characters INHERITANCE . Correlation
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Study on the Change Character of Double Rice Cold Damage in Hunan and Hubei Province during the Past 50 Years 被引量:2
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作者 帅细强 蔡荣辉 +3 位作者 刘敏 万素琴 谢佰承 刘志雄 《Meteorological and Environmental Research》 CAS 2010年第3期17-20,41,共5页
Based on the meteorological data of representative meteorological stations in Hunan and Hubei from 1961 to 2008 years,the change character of double rice cold damage under the background of climate change were analyze... Based on the meteorological data of representative meteorological stations in Hunan and Hubei from 1961 to 2008 years,the change character of double rice cold damage under the background of climate change were analyzed adopting 30 years glide accumulation method.The analysis showed that the 30 years sliding cumulative days of mild low-temperature during spring sowing in Hunan and Hubei were decreased in the recent 50 years,as well as the 30 years sliding cumulative days of moderate low-temperature in central south Hubei,northern and western Hunan.However,there was an increase in southern Hunan,so was the 30 years sliding cumulative days of severe low-temperature.The 30 years sliding cumulative days of mild low-temperature in May reduced in Hunan and Hubei.Instead,that of moderate low-temperature in May in central south Hubei was on the rise,and it was opposite in northern and southern Hunan,but there was no obvious change in western Hunan.The 30 years sliding cumulative days of severe low-temperature showed a decreasing tendency in May in central south Hubei,northern and western Hunan,and southern Hunan showed a contrary tendency.The 30 years sliding cumulative days of mild cold dew wind in Hunan and Hubei were decreased,that of moderate cold dew wind in central south Hubei,northern and western Hunan had the same tendency,but there was a contrary tendency in southern Hunan.The 30 years sliding cumulative days of severe cold dew wind was decreased in central south Hubei and increased in western Hunan,without cold dew wind in northern and southern Hunan. 展开更多
关键词 Cold damage Change character Hubei and Hunan Province Double rice China
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Main Agronomic Characters and Grain Quality of Rice Blast Resistance Gene Pi-d2 Transgenic Rice 被引量:6
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作者 陈德西 曲广林 +2 位作者 黄文娟 李婷 李仕贵 《Agricultural Science & Technology》 CAS 2011年第10期1457-1460,共4页
[Objective] The aim of this study was to provide metabolic evidence for the analysis of the ecological and safety assessment of Pi-d2-transgenic rice.[Method] The main agronomic characters of Pi-d2-transgenic rice wer... [Objective] The aim of this study was to provide metabolic evidence for the analysis of the ecological and safety assessment of Pi-d2-transgenic rice.[Method] The main agronomic characters of Pi-d2-transgenic rice were observed in field experiment and the grain chemical characters and amino acid content were measured.[Results] Introduction of foreign gene Pi-d2 resulted in stably hereditable variation in agronomic characteristics in the descents.Most of the transgenic lines grew normally and orderly.Compared with the control(wild type plants),about half of transgenic plants showed an increased or reduced plant height.There was no observable difference between transgenic plants and controls in tiller number,length of panicle,panicles per plant,seed-setting rate and 1 000-grain weight.Total amino acid content in transgenic rice was reduced,while the starch content,GC and GT were not altered in comparison with the control.[Conclusion] Introduction of foreign gene Pi-d2 has remarkable influence on plant height,while little on grain chemical characters. 展开更多
关键词 TRANSGENE Pi-d2 gene Rice Agronomic characters Amino acid
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Correlation Analysis of Characters of Indica Hybrid Rice with High Content of Amylose 被引量:4
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作者 杨扬 况浩池 +4 位作者 曾正明 罗俊涛 陈光珍 何兴材 付均 《Agricultural Science & Technology》 CAS 2013年第3期475-477,共3页
[Objective] The aim was to research and analyze characters and related correlation of indica hybrid rice containing high amylose. [Method] In the research, major characters of 16 species of groups of {ndica hybrid ric... [Objective] The aim was to research and analyze characters and related correlation of indica hybrid rice containing high amylose. [Method] In the research, major characters of 16 species of groups of {ndica hybrid rice and the correlation were explored in rice belts in Sichuan in 2011. [Result] The variation of chalkiness degree was the highest at 26.8%, followed by rate of head rice at 22.89%; varia- tions of head rice rate and chalkiness degree were lower at 0.72% and 2.61%. In addition, rate of unpolished rice was of significantly negative correlation with chalki- ness degree; rate of chalky rice was of extremely positive correlation with chalkiness degree and gel consistency; chalkiness degree was of significantly positive correla- tion with gel consistency; gel consistency was of significantly negative correlation with protein content; amylose content was of insignificant correlation with gel consis- tency (r=0.166 9) of the 16 hybrid groups. These indicated that gel consistency would be still high as the content of amylose grows (AC≥25%). For example, when the content of anylose in Chuanxiang 29A/Luhui 37, Kangfeng AJ6684, and Lefeng A/SR536 exceeded 27%, the gel consistency was over 80 mm in the research. [Conclusion] The research provides references for improvement of amylose content in breeding hybrid rice. 展开更多
关键词 Higher amylose content Indica hybrid rice characterS Correlaiton analysis
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Variation and Cluster Analysis on Leaf Characters from Different Provenance Sources of Polygonum multiflorum Thunb 被引量:2
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作者 韦艳梅 王凌晖 +2 位作者 曹福亮 韦山青 梁耀丹 《Agricultural Science & Technology》 CAS 2010年第6期94-98,共5页
[Objective] The aim was to study the variation of leaf characters from different provenance sources of Polygonum multiflorum Thunb,as well as to carry out cluster analysis on P.multiflorum from different provenance so... [Objective] The aim was to study the variation of leaf characters from different provenance sources of Polygonum multiflorum Thunb,as well as to carry out cluster analysis on P.multiflorum from different provenance sources to provide basis for the classification,identification,breeding and improved variety selection of P.multiflorum.[Method] Leaf shape characters of 31 copies of germplasm resources in the major distribution region of the whole country were determined,and the genetic variation of P.multiflorum leaves from different producing areas was analyzed.[Result] The leaf characters of single plant of the same experimental provenance source of P.multiflorum were relatively stable,the variation was mainly found on the single leaf area,1/2 leaf width,leaf width and other indicators;the variation of each leaf character among different provenance sources was obvious,and the variation was mainly found on the single leaf weight,leaf area,1/2 leaf width,leaf length and other indicators.The correlation analysis of each leaf character in P.multiflorum suggested that the single leaf area and single leaf weight showed extremely significant positive correlation with leaf length,1/2 leaf width,leaf width,leaf thickness and leaf stem length,while the single leaf area and single leaf weight showed significant negative correlation with WWR(leaf width/1/2 leaf width)and LWR(leaf length/1/2 leaf length),in addition,several macroscopic leaf characters such as leaf length,1/2 leaf width,leaf width,leaf stem length showed extremely positive correlation.The main component analysis result suggested that the contribution rate of accumulation variance of the front three main components was up to 97.4%,which could better reflect the comprehensive performance of leaf characters of different provenance sources of P.multiflorum.The cluster analysis showed that the experimental 31 copies of P.multiflorum provenance sources should be divided into three classes,the first class was distributed in the Middle,Western of Guizhou,northwestern of Guangxi and western areas with higher altitude;the second class was distributed in Hunan,Hubei,Sichuan,Guangdong and the most area of Guangxi;the third class was distributed in Anhui,Jiangsu and Henan and Shandong.[Conclusion] Cluster analysis of leaf characters indicated that the kinds of provenance sources which the geographical position was closer could be got together.The study had provided a certain basis for the classification of P.multiflorum. 展开更多
关键词 Polygonum multiflorum Thunb Leaf characters VARIATION Cluster analysis
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Vertical root distribution characters of Robinia pseudoacacia on the Loess Plateau in China 被引量:3
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作者 李鹏 赵忠 李占斌 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第2期87-92,i001,共7页
On the Loess Plateau, water is the main limiting factors for vegetation growth. Root distribution characters have special ecological meaning as it reflected the utilizations of trees to the environments. Even-aged sta... On the Loess Plateau, water is the main limiting factors for vegetation growth. Root distribution characters have special ecological meaning as it reflected the utilizations of trees to the environments. Even-aged stands ofRobinia pseudoacacia on slope lands facing south and north were selected as sampling plots for root distribution investigation. Investigatiing results showed that indicated that on all sites, root biomass decreased with depth, and the distribution depth of fine root was deeper than that of coarser root. The results of variance analysis indicated that there were great differences in root biomass among different diameter classes, and coarser root was the main sources of variance, and the root biomass, especially fine root (?<3mm) biomass on northern exposition sites was bigger than that on southern exposition sites. Analysis of the vertical root distribution parameters, root extinction coefficient, β indicated that the value of β on northern exposition was more than 0.982, while the value of β on southern exposition was less than 0.982, which indicated that the vertical root distribution depth ofRobinia pseudoacacia on southern exposition was deeper than that on southern exposition. And the distribution depth of fine roots (Φ<1mm) was deeper than that of thicker roots(Φ<3mm), which was in favor of the uptake of water and nutrients from deeper layers, helped the trees to adapt the arid environment, and promoted the growth of the upper parts of the tree. Keywords Root diameter classes - Variance analysis - Root extinction coefficient - Vertical distribution characters - Site conditions - Loess Plateau CLC number S792.27.01 Document code A Foundation Item: This research was supported by National Natural Science Foundation of China (30371150 and 40371075).Biography: LI Peng (1974-) male, post: Ph. D. in Northwest Scientific & Technological University of Agriculture and Forestry, Yangling 712100, Shaanxi Province, P. R. China. Tel: 029-82312651.Responsible editor: Chai Ruihal 展开更多
关键词 Root diameter classes Variance analysis Root extinction coefficient Vertical distribution characters Site conditions Loess Plateau
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Effects of Vermicompost on Agronomic Characters and Yield and Quality of Flue-cured Tobacco 被引量:2
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作者 黄德文 戴林建 +1 位作者 钟军 戴彬 《Agricultural Science & Technology》 CAS 2016年第6期1345-1348,共4页
The effects of vermicompost on the agronomic characters and yield and quality of flue-cured tobacco were investigated. The results showed that, the field growth periods of various treatments were 117-118 d, 1-2 days l... The effects of vermicompost on the agronomic characters and yield and quality of flue-cured tobacco were investigated. The results showed that, the field growth periods of various treatments were 117-118 d, 1-2 days longer than that of the CK. The numbers of effective leaves of the treatments applied with vermicompost were 0.1-0.3 leaf more than the CK. The highest yield and the highest proportion of high-grade tobacco occurred in treatment 3 as 2 095.5 kg/m^2 and 49%, respectively, which were higher than those in the CK by 6.58 kg and 5.3%. In conclusion, the treatment with the application of vermicompost at 7 500-10 500 kg/hm^2 was the best. 展开更多
关键词 VERMICOMPOST Flue-cured tobacco Agronomic characters Yield and quality
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Analysis on the Main Botanical Characters of 41 Cucurbita moschata Varieties 被引量:1
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作者 韩小霞 胡新军 +2 位作者 粟建文 袁祖华 李勇奇 《Agricultural Science & Technology》 CAS 2015年第9期1891-1896,共6页
In order to scientifically evaluate the values of Cucurbita moschata cultivars, main botanical characters including the initial flowering date, the first fruiting node, fruit length, fruit stem length, stem diameter, ... In order to scientifically evaluate the values of Cucurbita moschata cultivars, main botanical characters including the initial flowering date, the first fruiting node, fruit length, fruit stem length, stem diameter, internode length, the transverse and longitudinal diameters of the largest leaf, single fruit weight, flesh thickness and soluble solid content of 41 cultivars were measured for conducting diversity, correlation and cluster analysis. The results revealed that the pumpkin cultivars showed large variations in fruit stem length, single fruit weight, fruit length and flesh thickness, but small variations in initial flowering date. Significant, even highly significant correlations were found among the tested traits. Cluster analysis demonstrated that the 41 old Cucurbita moschata cultivars were divided into three groups, of which multiple traits of Group 1 were better than those in the other two groups. High similarities existed in three groups and the cultivars in each group. This research provided basis for selecting excellent traits and parents for the breeding of hybrids. 展开更多
关键词 Cucurbita moschata botanical character Diversity analysis Cluster analysis
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Effects of Nitrogen Quantity on Grain-filling Characters of Two-line Hybrid Rice with Large Ear 被引量:1
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作者 刘洪 李之林 +3 位作者 徐振江 王维 任永浩 肖立中 《Agricultural Science & Technology》 CAS 2012年第8期1621-1624,1674,共5页
[Objective] The aim was to research effects of N quantity on grain-filling characters of two-line hybrid rice cultivars with large ears. [Method] Peiza 67 and 88, two-line hybridized rice with large ears, were made us... [Objective] The aim was to research effects of N quantity on grain-filling characters of two-line hybrid rice cultivars with large ears. [Method] Peiza 67 and 88, two-line hybridized rice with large ears, were made use of to study on effects of N fertilizer in different quantities (LN: 90 kg/hm2;MN: 180 kg/hm2;HN: 270 kg/hm2) on plumpness and grain-filling characters. [Result] When N fertilizers were excessive, for inferior grains, grain-filling rate decreased and grain-filling time extended, resulting in plumpness decline after degradation of leaves' function. When N fertilizers were inadequate, maximal and average grain-filling rates decreased and the differences between superior and inferior grains in grain-filling rate increased, leading to decline of grain's weight and plumpness degree. On the other hand, quantity of N fertilizers had little effect on superior grains in plumpness. [Conclusion] The research provided references for reasonable use of N fertilizer and improvement of rice yield and N use. 展开更多
关键词 Nitrogen rate Two-line hybrid rice SEEDS characters of grain filling
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Supply-demand Evolution about Main Characters of Wheat Varieties in China 被引量:4
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作者 项诚 《Agricultural Science & Technology》 CAS 2009年第5期166-170,共5页
Using the data of wheat varieties with year-sown area of 6 666.7 hm^2 or more from 1982 to 2006 in China, the evolution of wheat varieties was studied from both supply and demand. Results showed that although various ... Using the data of wheat varieties with year-sown area of 6 666.7 hm^2 or more from 1982 to 2006 in China, the evolution of wheat varieties was studied from both supply and demand. Results showed that although various characters of wheat varieties grown by peasants in production were improved obviously in China, the demand for variety yield was still the main demand by peasants; there was no significant difference between the supply and demand of crude protein content by peasants; the demand for disease resistance has been lower than the supply recently; the demand for full growth stage at every stage was less than the supply; and while there was a larger demand for plant height by peasants. 展开更多
关键词 characterS EVOLUTION DEMAND Supply
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Behavior Response of Recreationists to Environment Characteristics of City Parks for Forest Recreation—A Case Study of City Parks of Jingzhou City in China 被引量:1
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作者 薛兴华 《Journal of Landscape Research》 2012年第1期44-48,共5页
By taking city parks of Jingzhou City as an example,city parks,as primary places for citizens' daily forest recreation,should present a certain recreational environment feature under the comprehensive effect of na... By taking city parks of Jingzhou City as an example,city parks,as primary places for citizens' daily forest recreation,should present a certain recreational environment feature under the comprehensive effect of nature,humanity,facilities,location and historical evolution.Through the empirical analysis of recreationists' behaviors in city parks with different environmental characters,it has obtained the differences of recreationists in composition,staying time and contents of recreational activities in different city parks,and that recreationists appear to adapt to the environmental characters.Recreational attractions and demands have manifested their perception towards the environmental characters of city parks.The distribution of recreational satisfaction has demonstrated that experience value of recreationists and environmental characters of city parks are consistent. 展开更多
关键词 CITY parks FOREST RECREATION ENVIRONMENTAL characterS Jingzhou CITY
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