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Relationship between plasma homocysteine and clinical grading of varicocele
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作者 Li-Hong Wang Lei Zheng +1 位作者 Hui Jiang Tao Jiang 《Asian Journal of Andrology》 2025年第4期495-501,共7页
This study aims to explore the correlation between plasma homocysteine (Hcy) levels and the clinical grading of varicocele (VC) when analyzing the potential pathogenesis of endothelial cells injury by Hcy. A total of ... This study aims to explore the correlation between plasma homocysteine (Hcy) levels and the clinical grading of varicocele (VC) when analyzing the potential pathogenesis of endothelial cells injury by Hcy. A total of 184 VC patients, aged 18–46 years, were included in this study. These patients visited The Second Hospital of Dalian Medical University (Dalian, China), between January 2022 and September 2024. Patients were divided into three groups based on clinical grading: Group A (59 cases, Grade I), Group B (28 cases, Grade II), and Group C (97 cases, Grade III). Additionally, 120 individuals with normal fertility test results during the same period were selected as the control group. Routine blood and biochemical indices were collected from the patients. Differences in clinical indices between groups were compared, and univariate and multivariate linear regression analyses were performed to identify factors associated with clinical grading. The results showed that the median Hcy levels in the control group and in patients with Grade I, II, and III VC were 9.56 (interquartile range [IQR]: 8.66, 14.02) µmol l−1, 11.28 (IQR: 9.71, 14.55) µmol l−1, 11.84 (IQR: 10.14, 15.60) µmol l−1, and 12.27 (IQR: 9.52, 15.40) µmol l−1, respectively. The differences between the four groups were statistically significant (χ2 = 12.41, P = 0.006). Multivariate regression analysis indicated that Hcy is a factor associated with the clinical grading of VC (t = 2.53, P = 0.013). Hcy is associated with the clinical grading and may have clinical value in assessing severity of VC. 展开更多
关键词 clinical grading HOMOCYSTEINE INFLAMMATION oxidative stress VARICOCELE
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Simulation of Preparation Process of Manufactured Sand Based on Discrete Element Method and Its Grading Influence on Pore Structure Distribution of Concrete
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作者 WANG Xi ZHANG Yunsheng +3 位作者 ZHANG Wenhua WANG Jinman QIAO Hongxia AN Baofeng 《Journal of Wuhan University of Technology(Materials Science)》 2025年第6期1702-1715,共14页
In order to clarify the preparation process parameters of manufactured sand,optimize its quality,and analyze the effect of its grading on the microstructure of concrete,the three-dimensional models of jaw crusher,vibr... In order to clarify the preparation process parameters of manufactured sand,optimize its quality,and analyze the effect of its grading on the microstructure of concrete,the three-dimensional models of jaw crusher,vibrating screen and conveyor belt were established by using SolidWorks 2016 software.Rocky DEM4.5 software was used to simulate the initial crushing,screening,and transportation stages of the manufactured sand preparation process,with Linear Spring Dashpot as the normal contact model and Coulomb as the tangential contact model;furthermore,the key process parameters were defined.The manufactured sand grading model was then proposed,thereby,the influence of the grading of manufactured sand on the distribution of pore structure in concrete and the interfacial transition zone(ITZ)was studied.The experimetal results show that the particle size of granite,after being crushed in the jaw crusher,is primarily concentrated between 80 and 130 mm,with a crushing energy consumption typically below 100000 J.However,certain instances of granite exhibit higher energy consumption due to undergoing multiple crushings within the chamber.At the same time,the granite causes significant wear on the jaw crusher plate.Furthermore,the tilt angle of the vibrating screen should be adjusted to between 10 and 15 degrees,while the layout angle of the conveyor belt needs to be set at 16 degrees.The proposed manufactured sand grading model is feasible,and the pore diameter distribution inside concrete increases with an increase in the fineness modulus of manufactured sand. 展开更多
关键词 GRANITE manufactured sand production process jaw crusher vibrating screen grading
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MVLA-Net:A Multi-View Lesion Attention Network for Advanced Diagnosis and Grading of Diabetic Retinopathy
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作者 Tariq Mahmood Tanzila Saba +2 位作者 Faten S.Alamri Alishba Tahir Noor Ayesha 《Computers, Materials & Continua》 2025年第4期1173-1193,共21页
Innovation in learning algorithms has made retinal vessel segmentation and automatic grading tech-niques crucial for clinical diagnosis and prevention of diabetic retinopathy.The traditional methods struggle with accu... Innovation in learning algorithms has made retinal vessel segmentation and automatic grading tech-niques crucial for clinical diagnosis and prevention of diabetic retinopathy.The traditional methods struggle with accuracy and reliability due to multi-scale variations in retinal blood vessels and the complex pathological relationship in fundus images associated with diabetic retinopathy.While the single-modal diabetic retinopathy grading network addresses class imbalance challenges and lesion representation in fundus image data,dual-modal diabetic retinopathy grading methods offer superior performance.However,the scarcity of dual-modal data and the lack of effective feature fusion methods limit their potential due to multi-scale variations.This paper addresses these issues by focusing on multi-scale retinal vessel segmentation,dual feature fusion,data augmentation,and attention-based grading.The proposed model aims to improve comprehensive segmentation for retinal images with varying vessel thicknesses.It employs a dual-branch parallel architecture that integrates a transformer encoder with a convolutional neural network encoder to extract local and global information for synergistic saliency learning.Besides that,the model uses residual structures and attention modules to extract critical lesions,enhancing the accuracy and reliability of diabetic retinopathy grading.To evaluate the efficacy of the proposed approach,this study compared it with other pre-trained publicly open models,ResNet152V2,ConvNext,Efficient Net,DenseNet,and Swin Transform,with the same developmental parameters.All models achieved approximately 85%accuracy with the same image preparation method.However,the proposed approach outperforms and optimizes existing models by achieving an accuracy of 99.17%,99.04%,and 99.24%,on Kaggle APTOS19,IDRiD,and EyePACS datasets,respectively.These results support the model’s utility in helping ophthalmologists diagnose diabetic retinopathy more rapidly and accurately. 展开更多
关键词 Diabetic retinopathy grading retinal vessel segmentation dual-modal deep learning attention mecha-nism health risks
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Persimmon Fruit Quality Grading Detection Based on an Improved YOLOv8s Lightweight Model
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作者 Haogang Wang Yunge Jing 《Journal of Electronic Research and Application》 2025年第5期209-218,共10页
Addressing challenges in accurately detecting persimmon fruit quality in orchards—such as reliance on manual grading,low efficiency,severe foliage obstruction,and subtle differences between quality grades—this paper... Addressing challenges in accurately detecting persimmon fruit quality in orchards—such as reliance on manual grading,low efficiency,severe foliage obstruction,and subtle differences between quality grades—this paper proposes a lightweight persimmon detection model based on an improved YOLOv8s architecture.First,the Conv layer in the backbone network is replaced with an ADown module to reduce model complexity.Second,MSFAN is introduced in the Neck layer to fully extract texture features from persimmon images,highlighting differences between quality grades.Finally,the Wise-IoU loss function mitigates the impact of low-quality sample data on grading accuracy.The improved model accurately identifies and separates persimmons of varying quality,effectively addressing quality grading detection in complex backgrounds.This provides a viable technical approach for achieving persimmon quality grading detection. 展开更多
关键词 Persimmon quality grading YOLOv8 Deep learning LIGHTWEIGHT Image detection
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Soil Fertility Grading in Tobacco—Rice Rotation Areas:A Case Study in Southern Hunan
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作者 XIAO Zi-man HAO Han-chi +5 位作者 XIAO Yan-song LI Xiao-hui LIU Yong-jun LONG Jian HOU Hong-bo PENG Pei-qin 《Agricultural Science & Technology》 2025年第1期31-44,共14页
As a paddy—upland rotation system, tobacco—rice rotation hastypical characteristics in the formation and evolution of soil fertility duringthe tobacco season with dry farming and rice season with water cultivation.T... As a paddy—upland rotation system, tobacco—rice rotation hastypical characteristics in the formation and evolution of soil fertility duringthe tobacco season with dry farming and rice season with water cultivation.To scientifically unveil the soil fertility formation process and grade thesoil fertility in tobacco—rice rotation areas, we collected 372 soil samplesfrom 11 tobacco stations (Haotang, Aoquan, Chengjiao, Renyi, Fangyuan,Anping, Huangsha, Taiping, Tushi, Dashiqiao, and Baimangying) in thetypical tobacco—rice rotation areas of Chenzhou and Yongzhou in SouthernHunan. The physical, chemical, and biological indicators of the soil sampleswere measured, and the tobacco and rice yields of each tobacco stationwere investigated. Machine learning was employed to screen the keyindicators influencing the tobacco yield, and a comprehensive numericalanalysis method combining principal component analysis and discriminantanalysis were adopted to cluster the sampling points, analyze their fertilityformation processes, and grade the soil fertility. The results showed thatclay content, available phosphorus, plow layer depth, slit-to-clay ratio, totalnitrogen, basal respiration, and organic carbon were identified as seven keyindicators influencing the tobacco yield. The results of the comprehensivenumerical analysis predicted two main processes involved in the formationof soil fertility in tobacco—rice rotation areas. One was the soil maturationprocess related to soil carbon and nitrogen cycling, and the other was theprocess of changes in soil physical properties such as clay content and slitto-clay ratio. According to the established soil fertility grading methodfor tobacco—rice rotation areas, the soil fertility of 11 tobacco stationswas graded. The results showed that the soil fertility was high in Haotang,Aoquan, Renyi, and Dashiqiao, medium in Huangsha and Tushi, and low inAnping, Baimangying, and Taiping. The tobacco and rice yields confirmedthat this grading standard can be effectively applied to the grading of soilfertility in the tobacco—rice rotation areas in Southern Hunan and canprovide a scientific basis for soil management in tobacco—rice rotation. 展开更多
关键词 Tobacco-rice rotation Soil fertility Machine learning Cluster analysis Soil fertility grading
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Automated Gleason Grading of Prostate Cancer from Low-Resolution Histopathology Images Using an Ensemble Network of CNN and Transformer Models
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作者 Md Shakhawat Hossain Md Sahilur Rahman +3 位作者 Munim Ahmed Anowar Hussen Zahid Ullah Mona Jamjoom 《Computers, Materials & Continua》 2025年第8期3193-3215,共23页
One in every eight men in the US is diagnosed with prostate cancer,making it the most common cancer in men.Gleason grading is one of the most essential diagnostic and prognostic factors for planning the treatment of p... One in every eight men in the US is diagnosed with prostate cancer,making it the most common cancer in men.Gleason grading is one of the most essential diagnostic and prognostic factors for planning the treatment of prostate cancer patients.Traditionally,urological pathologists perform the grading by scoring the morphological pattern,known as the Gleason pattern,in histopathology images.However,thismanual grading is highly subjective,suffers intra-and inter-pathologist variability and lacks reproducibility.An automated grading system could be more efficient,with no subjectivity and higher accuracy and reproducibility.Automated methods presented previously failed to achieve sufficient accuracy,lacked reproducibility and depended on high-resolution images such as 40×.This paper proposes an automated Gleason grading method,ProGENET,to accurately predict the grade using low-resolution images such as 10×.This method first divides the patient’s histopathology whole slide image(WSI)into patches.Then,it detects artifacts and tissue-less regions and predicts the patch-wise grade using an ensemble network of CNN and transformer models.The proposed method adapted the International Society of Urological Pathology(ISUP)grading system and achieved 90.8%accuracy in classifying the patches into healthy and Gleason grades 1 through 5 using 10×WSI,outperforming the state-of-the-art accuracy by 27%.Finally,the patient’s grade was determined by combining the patch-wise results.The method was also demonstrated for 4−class grading and binary classification of prostate cancer,achieving 93.0%and 99.6%accuracy,respectively.The reproducibility was over 90%.Since the proposedmethod determined the grades with higher accuracy and reproducibility using low-resolution images,it is more reliable and effective than existing methods and can potentially improve subsequent therapy decisions. 展开更多
关键词 Gleason grading prostate cancer whole slide image ensemble learning digital pathology
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Development and validation of a predictive model for portal-systemic venous invasion grading in borderline resectable pancreatic cancer
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作者 Fang-Fei Wang Xiao-Di Dai +2 位作者 Xin Zhao Qiang He Shao-Cheng Lyu 《World Journal of Gastroenterology》 2025年第42期103-113,共11页
BACKGROUND Portosystemic venous invasion(PSVI)depth critically influences prognosis in borderline resectable pancreatic cancer(BRPC),necessitating precise preoperative discrimination for personalized therapy.AIM To de... BACKGROUND Portosystemic venous invasion(PSVI)depth critically influences prognosis in borderline resectable pancreatic cancer(BRPC),necessitating precise preoperative discrimination for personalized therapy.AIM To develop and validate a preoperative nomogram integrating computed to-mography parameters and carbohydrate antigen 19-9(CA19-9)kinetics for pre-dicting PSVI depth in treatment-naive BRPC.METHODS This retrospective cohort study analyzed 167 BRPC patients undergoing radical resection between 2011 and 2023.Patients were stratified by pathological PSVI depth[no venous invasion(VI)/adventitial/muscularis propria/intimal].Kaplan-Meier and ordinal logistic regression identified preoperative predictors from clinical/laboratory/computed tomography parameters(e.g.,circumferential involvement and CA19-9).A nomogram was developed and validated via cali-bration curves/decision curve analysis.RESULTS PSVI depth significantly stratified survival.:Intimal VI showed worst prognosis(median overall survival:9 months,5-year overall survival:0%vs no VI:17 months,12.5%;P<0.001).Independent predictors:CA19-9[odds ratio(OR)=3.819,Wald=14.125,95%confidence interval(CI):1.980-7.410],circumferential involvement(OR=8.271,Wald=33.352,95%CI:3.950-17.320),and luminal compromise(OR=3.544,Wald=8.489,95%CI:1.818-6.447).The nomogram achieved C-index=0.928(95%CI:0.889-0.967),with 100-250 points indicating high invasiveness risk.Decision curve analysis confirmed clinical utility(threshold:0-0.7).CONCLUSION This model integrates routine indicators to preoperatively quantify PSVI depth,guiding precision treatment. 展开更多
关键词 Borderline resectable pancreatic cancer Portosystemic venous invasion Pathological grading Predictive model Adventitial invasion Muscularis propria invasion Intimal invasion
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Rapid pathologic grading-based diagnosis of esophageal squamous cell carcinoma via Raman spectroscopy and a deep learning algorithm
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作者 Xin-Ying Yu Jian Chen +2 位作者 Lian-Yu Li Feng-En Chen Qiang He 《World Journal of Gastroenterology》 2025年第14期32-46,共15页
BACKGROUND Esophageal squamous cell carcinoma is a major histological subtype of esophageal cancer.Many molecular genetic changes are associated with its occurrence.Raman spectroscopy has become a new method for the e... BACKGROUND Esophageal squamous cell carcinoma is a major histological subtype of esophageal cancer.Many molecular genetic changes are associated with its occurrence.Raman spectroscopy has become a new method for the early diagnosis of tumors because it can reflect the structures of substances and their changes at the molecular level.AIM To detect alterations in Raman spectral information across different stages of esophageal neoplasia.METHODS Different grades of esophageal lesions were collected,and a total of 360 groups of Raman spectrum data were collected.A 1D-transformer network model was proposed to handle the task of classifying the spectral data of esophageal squamous cell carcinoma.In addition,a deep learning model was applied to visualize the Raman spectral data and interpret their molecular characteristics.RESULTS A comparison among Raman spectral data with different pathological grades and a visual analysis revealed that the Raman peaks with significant differences were concentrated mainly at 1095 cm^(-1)(DNA,symmetric PO,and stretching vibration),1132 cm^(-1)(cytochrome c),1171 cm^(-1)(acetoacetate),1216 cm^(-1)(amide III),and 1315 cm^(-1)(glycerol).A comparison among the training results of different models revealed that the 1Dtransformer network performed best.A 93.30%accuracy value,a 96.65%specificity value,a 93.30%sensitivity value,and a 93.17%F1 score were achieved.CONCLUSION Raman spectroscopy revealed significantly different waveforms for the different stages of esophageal neoplasia.The combination of Raman spectroscopy and deep learning methods could significantly improve the accuracy of classification. 展开更多
关键词 Raman spectroscopy Esophageal neoplasia Early diagnosis Deep learning algorithm Rapid pathologic grading
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The Identification and Assessment on Genetic Characteristics in Grading Breeding Sheep Populations with Microsatellite Markers 被引量:7
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作者 金鑫 苏蕊 +1 位作者 张文广 李金泉 《Agricultural Science & Technology》 CAS 2008年第6期21-24,共4页
[Objective] The aim of the research was to identify and assess the genetic characteristics of grading breeding sheep populations in Ba Yan Nur City. [Method] Genetic polymorphism and aggregation of seven sheep populat... [Objective] The aim of the research was to identify and assess the genetic characteristics of grading breeding sheep populations in Ba Yan Nur City. [Method] Genetic polymorphism and aggregation of seven sheep populations, including three breeding sheep populations (breeding F1, F2 and Bamei mutton sheep), three introduced mutton sheep breeds (Texel, Dorset and German Merino sheep) and one local female parent population (Mongolia sheep), were assessed using 10 microsatellite markers. [Result] By cluster analysis, the seven sheep populations can be divided into two groups. The F1 and German Merino sheep were closely related, which were clustered with F2, Bamei mutton sheep and Mongolia sheep to form one group while Texel and Dorset to form another group. The genetic aggregation of the seven breeds was assessed by Bayesian discrimination. And the results show that the genetic aggregation of F1 and F2 were lower while that of Bamei mutton sheep, Texel, Dorset and German Merino sheep were higher. [Conclusion] Better genetic stability has been formed in Bamei mutton sheep. 展开更多
关键词 grading BREEDING MICROSATELLITE MARKERS Genetic polymorphism Bayesian discrimination
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Variation and Probability Grading of Fruit Firmness in Peach Germplasm Resource 被引量:4
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作者 马之胜 王越辉 +2 位作者 贾云云 宣立锋 王建学 《Agricultural Science & Technology》 CAS 2009年第6期91-93,共3页
Objective The aim was to provide basis for further studies on fruit firmness in peach fruits and the standardization and standardization of peach germplasm resource. [ Method] The analysis of fruit firmness of peach g... Objective The aim was to provide basis for further studies on fruit firmness in peach fruits and the standardization and standardization of peach germplasm resource. [ Method] The analysis of fruit firmness of peach germplasm resource was based on the improved firmness measurement, and the probability grading of characteristics was carried out on peach fruit firmness. [Result] The coefficient of variation of peach fruit firmness with skin was less than that of fruit firmness without skin; the fruit firmness with skin and fruit firmness without skin were both fitted the normal distribution; the probability grading of characteristics were divided into five series based on four points of (X-1. 281 8s), (X-0. 524 6s), (X+0. 524 6s) and (X+1.281 8s), so that the probability of 1 -5 were 10%, 20%, 40%, 20% and 10%. [Conclusion] There was more abundant genetic basis in fruit firmness, which held a potential for greater choice. 展开更多
关键词 Peach germplasm Fruit firmness VARIATION Probability grading
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Performance of bottleneck shifting for remanufacturing system considering returns' quality grading 被引量:2
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作者 郑玉巧 苏春 +1 位作者 曹白雪 施杨梅 《Journal of Southeast University(English Edition)》 EI CAS 2015年第4期516-521,共6页
Aimed at the remanufacturing system, the effect of the uncertainty of returns' quality on bottleneck shifting is investigated. A novel definition of bottleneck station is presented and the probability of a station be... Aimed at the remanufacturing system, the effect of the uncertainty of returns' quality on bottleneck shifting is investigated. A novel definition of bottleneck station is presented and the probability of a station becoming a bottleneck is also given. By calculating the effective output, the effective operation time (EOT) and the ratio of EOT of each station, the system's current bottleneck of effective output time is determined. By calculating the probability coefficient of variation and index of bottleneck shifting, the quantitative performance of bottleneck shifting is obtained. Discrete event simulation and the experiment design method are adopted to simulate the system, in which the proportion of quality grading, repair rates and process routes are considered. The case study shows that the uncertainty of returns' quality greatly increases the probability of bottleneck shifting, and with the increase of the discrete degree of the returns' repair rate, the bottleneck shifting phenomenon is more obvious. Furthermore, bottleneck shifting is closely related to the process route of the dominating returns' quality grade. 展开更多
关键词 bottleneck shifting REMANUFACTURING returns quality grading UNCERTAINTY
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Study on Grading Standard for One-Year-Old Container Seedling Quality of Phoebe zhennan 被引量:2
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作者 陈孝 纪程灵 +2 位作者 周正清 彭先凤 杜昌远 《Agricultural Science & Technology》 CAS 2014年第11期1990-1994,共5页
In order to improve the survival rate of planting seedlings of Phoebe zhen-nan, the grading standard for one-year-old container seedlings of Phoebe zhennan was developed by using cluster analysis. The results showed t... In order to improve the survival rate of planting seedlings of Phoebe zhen-nan, the grading standard for one-year-old container seedlings of Phoebe zhennan was developed by using cluster analysis. The results showed that the quality of Phoebe zhennan container seedlings could be estimated from seedling height and ground diameter. The Phoebe zhennan container seedlings were divided into 3 grades: Grade 1 (seedling height ≥ 38 cm; ground diameter ≥ 0.65 cm), Grade 2 (31.7 cm ≤ seedling height 〈 38 cm; 0.56 cm ≤ ground diameter 〈 0.65 cm) and Grade 3 (seedling height 〈 31.7 cm; ground diameter 〈 0.56 cm). 展开更多
关键词 Phoebe zhennan Container seedling Cluster analysis Seedling grading
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Grading Standards of the Coefficient of Variation in the Electronic Raw Silk Size Testing 被引量:2
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作者 许建梅 白伦 +1 位作者 伍冬平 吴克峰 《Journal of Donghua University(English Edition)》 EI CAS 2007年第2期235-239,共5页
In order to shorten the difference between the raw silk size grading standards of the world and that of China, to quicken the step of the electronic raw silk testing process, the distribution of the coefficient of var... In order to shorten the difference between the raw silk size grading standards of the world and that of China, to quicken the step of the electronic raw silk testing process, the distribution of the coefficient of variation (CV50m%) of the raw silk size in the electronic testing and the development of the new standards are studied according to the sampling and grading theory. By the theoretical deduction and the simulating experiments, the distribution of the coefficient of variation of the raw silk size is given, and the grading scheme whose quality index is the coefficient of variation(CV50m%)of the raw silk size and the grading precisions of all grades are proposed. Moreover, the rightness and the feasibility of the grading scheme are testified by the sampling and grading simulation. 展开更多
关键词 coefficient of variation sampling method grading standard grading precision
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Effects of Specific Gravity-based Seed Grading on Seed Germination, Seedling Emergence and Grain Yield of Hybrid Rice
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作者 崔婷 王晓敏 +2 位作者 秦建权 邓化冰 唐启源 《Agricultural Science & Technology》 CAS 2015年第10期2099-2103,共5页
Using the commercial seeds of two hybrid rice varieties including Lu- liangyou 996 and Liangyoupeijiu as the materials, four specific gravity-based seed grading treatments, Le., the specific gravity of 〈1.0 (T1), 1... Using the commercial seeds of two hybrid rice varieties including Lu- liangyou 996 and Liangyoupeijiu as the materials, four specific gravity-based seed grading treatments, Le., the specific gravity of 〈1.0 (T1), 1.0-1.09 (T2), 1.1-1.19(T3) and ≥1.2 (T4), by selection with different saline solutions, and the control without seed grading (CK) were designed to study the effects of seed grading on seed germination, seedling emergence, seedling quality and grain yield. The results showed that the treatments of T2, T3 and T4 had higher or significantly higher seed germination rate, germination index and vigor index, seedling emergence rate and adult seedling rate than the CK, while T1 had significantly lower values of these traits than the CK. Compared with the CK, the number of spikelets per pani- cle was found to be the main reason for the yield increase of these treatments with high seed viability. 展开更多
关键词 Hybrid rice Seed grading Seed vigor Germination rate Grain yield
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The Measurement and Grading of Pressure on Cultivated Land in City-level in Yunnan Province 被引量:3
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作者 杨青 杨子生 《Agricultural Science & Technology》 CAS 2015年第7期1562-1564,共3页
For a long time pressure on cultivated land receives much concern be- cause of close relationship with food security. In Yunnan provice,natural conditions of mountain area are poor and the overall quality of cultivate... For a long time pressure on cultivated land receives much concern be- cause of close relationship with food security. In Yunnan provice,natural conditions of mountain area are poor and the overall quality of cultivated land is :not high. This paper selected state (city) level as research scale,calculated the pressure index on cultivated land of 16 states (cities) in Yunnan provice,revealed the level of tension states (cities) of cultivated land,provided basic basis for determining amount of culti- vated land of provice and states and developing the policy about cultivated land protection.The study indicated that pressure on cultivated land in Dehong belongs to "no pressure" grade,in Qujing and Baoshan belong to "critical pressure "grade,in Yuxi and Zhaotong belong to "moderate-pressure"grade,in Kunming and Nujiang be- longs to "high-pressure" and in the rest 9 states belongs to "low-pressure"grade. 展开更多
关键词 Pressure on cultivated land grading Yunnan Province
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Present Situation and Prospect of Professional Grading and Loose-leaf Purchasing of Flue-cured Tobacco 被引量:1
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作者 袁胜国 李光雷 +1 位作者 张灿洪 冯景飞 《Agricultural Science & Technology》 CAS 2014年第4期538-541,556,共5页
In terms of the common practice of professional grading and loose-leaf purchasing technology, the advantages of these technologies were demonstrated. The problems and proposals of the professional grading leaves purch... In terms of the common practice of professional grading and loose-leaf purchasing technology, the advantages of these technologies were demonstrated. The problems and proposals of the professional grading leaves purchasing model were also summarized and analyzed, so as to provide practical experiences for fur- ther promotion of loose-leaf purchasing. 展开更多
关键词 Flue-cured tobacco Loose leaf grading PURCHASING
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Experimental study on the moving characteristics of fine grains in wide grading unconsolidated soil under heavy rainfall 被引量:40
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作者 CUI Yi-fei ZHOU Xiao-jun GUO Chao-xu 《Journal of Mountain Science》 SCIE CSCD 2017年第3期417-431,共15页
The initiation mechanism of debris flow is regarded as the key step in understanding the debrisflow processes of occurrence, development and damage. Moreover, migration, accumulation and blocking effects of fine parti... The initiation mechanism of debris flow is regarded as the key step in understanding the debrisflow processes of occurrence, development and damage. Moreover, migration, accumulation and blocking effects of fine particles in soil will lead to soil failure and then develop into debris flow. Based on this hypothesis and considering the three factors of slope gradient, rainfall duration and rainfall intensity, 16 flume experiments were designed using the method of orthogonal design and completed in a laboratory. Particle composition changes in slope toe, volumetric water content, fine particle movement characteristics and soil failure mechanism were analyzed and understood as follows: the soil has complex, random and unstable structures, which causes remarkable pore characteristics of poor connectivity, non-uniformity and easy variation. The major factors that influence fine particle migration are rainfall intensity and slope. Rainfall intensity dominates particle movement, whereby high intensity rainfall induces a large number of mass movement and sharp fluctuation, causing more fine particles to accumulate at the steep slope toe. The slope toe plays an important role in water collection and fine particleaccumulation. Both fine particle migration and coarse particle movement appears similar fluctuation. Fine particle migration is interrupted in unconnected pores, causing pore blockage and fine particle accumulation, which then leads to the formation of a weak layer and further soil failure or collapses. Fine particle movement also causes debris flow formation in two ways: movement on the soil surface and migration inside the soil. The results verify the hypothesis that the function of fine particle migration in soil failure process is conducive for further understanding the formation mechanism of soil failure and debris flow initiation. 展开更多
关键词 Wide grading unconsolidated soil Fine particle migration Soil failure LANDSLIDE Debris flow initiation Flume test Heavy rainfall
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Method of Modulation Recognition Based on Combination Algorithm of K-Means Clustering and Grading Training SVM 被引量:11
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作者 Faquan Yang Ling Yang +3 位作者 Dong Wang Peihan Qi Haiyan Wang 《China Communications》 SCIE CSCD 2018年第12期55-63,共9页
For the existing support vector machine, when recognizing more questions, the shortcomings of high computational complexity and low recognition rate under the low SNR are emerged. The characteristic parameter of the s... For the existing support vector machine, when recognizing more questions, the shortcomings of high computational complexity and low recognition rate under the low SNR are emerged. The characteristic parameter of the signal is extracted and optimized by using a clustering algorithm, support vector machine is trained by grading algorithm so as to enhance the rate of convergence, improve the performance of recognition under the low SNR and realize modulation recognition of the signal based on the modulation system of the constellation diagram in this paper. Simulation results show that the average recognition rate based on this algorithm is enhanced over 30% compared with methods that adopting clustering algorithm or support vector machine respectively under the low SNR. The average recognition rate can reach 90% when the SNR is 5 dB, and the method is easy to be achieved so that it has broad application prospect in the modulating recognition. 展开更多
关键词 CLUSTERING ALGORITHM FEATURE extraction grading ALGORITHM support VECTOR machine MODULATION recognition
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Influence of Coal Gangue Aggregate Grading on Strength Properties of Concrete 被引量:11
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作者 WANG Zhenshuang ZHAO Ning 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2015年第1期66-72,共7页
This paper investigates the feasibility of using coal gangue as coarse and fine aggregates in concrete as well as how the coal gangue aggregate grading affects concrete properties. Nine mixed concrete samples were pre... This paper investigates the feasibility of using coal gangue as coarse and fine aggregates in concrete as well as how the coal gangue aggregate grading affects concrete properties. Nine mixed concrete samples were prepared with the value n in Fuller's curve ranged from 0.44 to 0.68. The coal gangue aggregate with n = 0.62 shows the highest density, water absorption, cylinder strength and the lowest voids. The results indicate that using coal gangue as coarse and fine aggregate in concrete is tech- nically feasible and useful. When n is 0.62, the values of the slump, 28-day compressive, splitting tensile strength, flexural strength and elasticity modulus of coal gangue concrete reach the highest. The highest 7-day and 28-day compressive strength were 24 MPa and 37 MPa in mix CG7, respectively. It is possible to produce grade 30 coal gangue concrete with coal gangue coarse and fine aggregate. 展开更多
关键词 coal gangue aggregate Fuller’s curve WORKABILITY STRENGTH modulus of elasticity grading
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Liver pathology of hepatitis C,beyond grading and stagingof the disease 被引量:6
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作者 Sadhna Dhingra Stephen C Ward Swan N Thung 《World Journal of Gastroenterology》 SCIE CAS 2016年第4期1357-1366,共10页
Liver biopsy evaluation plays a critical role in management of patients with viral hepatitis C. In patients with acute viral hepatitis, a liver biopsy, though uncommonly performed, helps to rule out other nonviral cau... Liver biopsy evaluation plays a critical role in management of patients with viral hepatitis C. In patients with acute viral hepatitis, a liver biopsy, though uncommonly performed, helps to rule out other nonviral causes of deranged liver function. In chronic viral hepatitis C, it is considered the gold standard in assessment of the degree of necroinflammation and the stage of fibrosis, to help guide treatment and determine prognosis. It also helps rule out any concomitant diseases such as steatohepatitis, hemochromatosis or others. In patients with chronic progressive liver disease with cirrhosis and dominant nodules, a targeted liver biopsy is helpful in differentiating a regenerative nodule from dysplastic nodule or hepatocellular carcinoma. In the setting of transplantation, the liver biopsy helps distinguish recurrent hepatitis C from acute rejection and also is invaluable in the diagnosis of fibrosing cholestatic hepatitis, a rare variant of recurrent hepatitis C. This comprehensive review discusses the entire spectrum of pathologic findings in the course of hepatitis C infection. 展开更多
关键词 HEPATITIS C Liver PATHOLOGY BIOPSY grading STAGING NEOPLASIA
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