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Construction of the Ontology-Based Agricultural Knowledge Management System

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Journal of Integrative Agriculture 2012年第5期11卷 700-709页

作者： ZHENG Ye-lu HE Qi-yun QIAN ping li Ze Institute of Science and Technology Information Guangdong Academy of Agricultural SciencesGuangzhou 510640P.R.China

Ontology is the formal representation of concepts and their mutual relations. It has wide application potential in the classification of agricultural information, the construction of information and knowledge database, the research and development of intelligent search engine, as well as the realization of cooperative information service, etc. In this research, an ontology-based agricultural knowledge management system framework is proposed, which includes modules of ontology-based knowledge acquisition, knowledge representation, knowledge organization, and knowledge mining, etc. The key technologies, building tools and applications of the framework are explored. Future researches on the theoretical refinement and intelligent simulation knowledge service are also envisioned.

关键词： agriculture ontology knowledge management system construction

Prevalence of amblyopia among preschool children in central south China

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International Journal of Ophthalmology(English edition) 2019年第5期12卷 820-825页

作者： yun-ping li Meng-Wen Zhou Susan H Forster Si-Ying Chen Xin Qi Hui-Ming Zhang Jing Luo Department of Ophthalmology the Second Xiangya HospitalCentral South University Hunan Clinical Research Center of Ophthalmic Disease Department of Ophthalmology and Visual Science Yale University School of Medicine Department of Ophthalmology Hainan Provincial People's Hospital Department of Dermatology the Second Xiangya HospitalCentral South University

AIM: To determine the prevalence and factors associated with amblyopia among children aged 30-83 mo in central south of ***: A population-based, cross-sectional study was conducted in children aged 30-83 mo in Changsha(an urban city) and Zhangjiajie(a rural area) in central south of China. Clinical examinations including ocular alignment, ocular motility, visual acuity(VA), prism cover test, cycloplegic refraction, slit lamp examination and fundus examination were performed by trained study ophthalmologists and optometrists. Unilateral amblyopia was defined as a 2-line difference between eyes with VA<20/32 in the worse eye and with coexisting anisometropia [≥1.00 D spherical eutivalent(SE) for hyperopia, ≥3.00 D SE for myopia, and ≥1.50 D for astigmatism], strabismus, or past or present visual axis obstruction. Bilateral amblyopia was defined as VA in both eyes <20/40(≥ 48-month-old) and <20/50(< 48-month-old), with coexisting hyperopia ≥4.00 D SE, myopia ≤-6.00 D SE, and astigmatism ≥2.50 D, or past or present visual axis ***: There were 8042 children enrolled and 7713 children were screened. The amblyopia prevalence in children aged 30-83 mo was 1.09%(95% confidence interval, 0.86%-1.35%) with no age(P=0.81), gender(P=0.46) or area distribution(P=0.93) differences. Of these, 0.68% were unilateral cases and 0.41% were bilateral cases. Underlying causes included anisometropia(40%), binocular refractive error(36%), strabismus(14%) and deprivation(10%). Hyperopia combined with astigmatism was the frequent refractive error for ametropic and anisometropic ***: In this rural and urban Chinese population, 1.09% of children with 30-83 mo of age had amblyopia, a prevalence rate similar to that of many other studies. Anisometropia and refractive error are the most common causes of unilateral and bilateral amblyopia respectively.

关键词： amblyopia prevalence rural urban Chinese

Sex-dependent alterations in extracellular vesicles linking chronic spinal cord injury to brain neuroinflammation and neurodegeneration

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Neural Regeneration Research 2025年第2期20卷 483-484页

作者： yun li Junfang Wu Department of Anesthesiology&Shock Trauma and Anesthesiology Research(STAR)CenterUniversity of Maryland School of MedicineBaltimoreMDUSA

Traumatic spinal cord injury(SCI)is a devastating exogenous injury with long-lasting consequences and a leading cause of death and disability *** in assistive technology,rehabilitative interventions,and the ability to identify and intervene in secondary conditions have significantly increased the long-term survival rate of SCI patients,with some people even living well into their seventh or eighth *** survival changes have led neurotrauma researchers to examine how SCI interacts with brain *** health and epidemiological data showed that patients with long-term SCI can have a lower life expectancy and quality of life,along with a higher risk of comorbidities and complications.

关键词： alterations inflammation injury

Deformation inhomogeneity due to sample-anvil friction in cylindrical compression test

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Transactions of Nonferrous Metals Society of China 2019年第2期29卷 279-286页

作者： Xian-jue YE Xiao-juan GONG Biao-biao YANG yun-ping li Yan NIE State Key Laboratory for Powder Metallurgy Central South UniversityChangsha 410083China Yuanmeng Precision Technology(Shenzhen)Institute Shenzhen 518000China

Finite element(FEM)analysis was used to systematically evaluate the inhomogeneity of deformation in cylindrical samples with various sample-anvil friction coefficients,*** was found that the level of friction strongly influences the deformation homogeneity,which increases significantly with the friction coefficient although the overall geometry of the samples almost remains the same when m >*** position,at which the effective strain along the maximum radial direction in a compressed sample is equal to the equivalent strain of the sample,does not vary greatly with respect to both equivalent strain of the sample and *** measurements of compressed cylindrical 5056B Al alloy samples revealed a change of effective strain distribution similar to that revealed by FEM *** exists a quantitative relationship between the hardness and the effective strain if no recrystallization or recovery occurs during the compression process.

关键词： compression friction coefficient barreling,cylinder deformation inhomogeneity

Ag+-selective luminescent sensing of coordination polymers with functional pores

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Ag+-selective luminescent sensing of coordination polymers w...

Effects of Partially N-acetylated Chitosans to Elicit Resistance Reaction on Brassica napus L.

河南省化学会2016年学术年会

作者： ling-yun Xin Guang-Zhen liu Lu-Fang Ma Xiao-ling li yun-ping li College of Chemistry and Chemical Engineering Luoyang Normal University

Recently,many coordination polymers(CPs) with functional pores have been considered to be the compelling and promising devices for sensing small inorganic and organic molecules and metal ***,some of those CPs show excellent luminescent sensing properties towards metal ions such as Al,Cu,Fe,et *** is because the Lewis basic coordination sites existed in the networks of CPs can interact with special metal ions,which may result in the changes in the luminescent intensity of the CPs-based ***,some MOFs bearing such sites have been reported,including Eu(Ⅲ)-CPs with many Lewis basic pyridine nitrogen atoms for sensing of Cu ions,and Zn(Ⅱ)-CPs with uncoordinated Lewis-base sites showing excellent luminescence sensing of inorganic *** course,there are other approaches which can improve the sensing efficiency except for the retention of Lewis base sites within the ***,we present a hydrogen-bonded microporous networks with exposed Lewis basic pyridine nitrogen atoms({[Cd(HTZ-IP)(HPYTZ)(HO)]-6HO}n),hydrothermally prepared by a mixed-ligand strategy with the combination of a rigid 5-(tetrazol-5-yl)isophthalic acid(HTZ-HIP) and 3,5-di(4-pyridyl)-1,2,4- triazolate ligand((HPYTZ).Importantly,we have demonstrated that the infinite CPs is capable of detecting Ag in water *** a sensing material for Ag,this CPs has features including simple preparation procedure,fast detection time,excellent selectivity for Ag,and high sensitivity with a detection range of 10-10M/L concentration limit.

关键词： luminescent sensing coordination polymers HTZ-H2IP HPYTZ

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Agricultural Sciences in China 2002年第5期1卷 516-519页

作者： ZHANG Xue-kun, TANG Zhang-lin, CHEN li, GUO Yi-hong, CHEN yun-ping and li Jia-na(Agronomy Department, Southwest Agricultural University , Chongqing 400716 , China) Agronomy Department Southwest Agricultural University Chongqing 400716 China

The effects to elicit resistance reaction on oilseed rape (Brassica napus L. cv Xinongchangjiao ) by four partially N-acetylated chitosan 7B, 8B, 9B and 10B (Degree of acetylation (D. A.) is 30% , 20% , 10%, 0%, respectively) and Glycol chitosan (GC, D.A. is 0%) were investigated and compared. Results showed that chitosan were similar to salicylic acid (SA), and could induce resistance reaction, but the reaction was influenced by the degree of acetylation of chitosan. Fully deacetylated chitosans, 10B and GC, elicited chitinase activity, but partially acetylated chitosan, 7B, 8B and 9B, inhibited chitinase activity. Phenyalanine ammonia-lyase (PAL) was also elicited. Elicitor activity increased with on increasing degree of acetylation, 7B induced highest PAL activity among all chitosans. All chitosans induced peroxidase (POD) in a similar level. After elicited by glycol chitosan, like SA treatment, the seedlings increased disease resistance to Sclerotinia sclerotiorum significantly.

关键词： Brassica napus L. Chitosan Degree of acetylation Resistance reaction

IoT Empowered Early Warning of Transmission line Galloping Based on Integrated Optical Fiber Sensing and Weather Forecast Time Series Data

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Computers, Materials & Continua 2025年第1期82卷 1171-1192页

作者： Zhe li yun liang Jinyu Wang Yang Gao State Grid Henan Electric Power Company Electric Power Scientific Research Institute State Grid Henan Electric Power CompanyZhengzhou450052China

Iced transmission line galloping poses a significant threat to the safety and reliability of power systems,leading directly to line tripping,disconnections,and power *** early warning methods of iced transmission line galloping suffer from issues such as reliance on a single data source,neglect of irregular time series,and lack of attention-based closed-loop feedback,resulting in high rates of missed and false *** address these challenges,we propose an Internet of Things(IoT)empowered early warning method of transmission line galloping that integrates time series data from optical fiber sensing and weather ***,the method applies a primary adaptive weighted fusion to the IoT empowered optical fiber real-time sensing data and weather forecast data,followed by a secondary fusion based on a Back Propagation(BP)neural network,and uses the K-medoids algorithm for clustering the fused ***,an adaptive irregular time series perception adjustment module is introduced into the traditional Gated Recurrent Unit(GRU)network,and closed-loop feedback based on attentionmechanism is employed to update network parameters through gradient feedback of the loss function,enabling closed-loop training and time series data prediction of the GRU network ***,considering various types of prediction data and the duration of icing,an iced transmission line galloping risk coefficient is established,and warnings are categorized based on this ***,using an IoT-driven realistic dataset of iced transmission line galloping,the effectiveness of the proposed method is validated through multi-dimensional simulation scenarios.

关键词： Optical fiber sensing multi-source data fusion early warning of galloping time series data IoT adaptive weighted learning irregular time series perception closed-loop attention mechanism

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厚煤层综放双巷工作面巷间煤柱尺寸研究

岩土力学 2017年第10期38卷 3009-3016页

作者：王琦樊运平李刚郭文孝闫殿华张立平中国煤炭科工集团太原研究院山西太原030006 山西天地煤机装备有限公司山西太原030006

为解决厚煤层综放双巷布置工作面巷间煤柱的留设问题,以某矿四盘区4301工作面运输顺槽与辅助运输顺槽之间的煤柱为工程背景,首先对巷间煤柱进行理论分析:一次采动影响后将巷间煤柱沿倾向划分为采动影响区、相对稳定区和锚杆支护区,应用... 详细信息

为解决厚煤层综放双巷布置工作面巷间煤柱的留设问题,以某矿四盘区4301工作面运输顺槽与辅助运输顺槽之间的煤柱为工程背景,首先对巷间煤柱进行理论分析:一次采动影响后将巷间煤柱沿倾向划分为采动影响区、相对稳定区和锚杆支护区,应用极限平衡理论分析得出了一次采动影响区的宽度为2.82 m,进而得出巷间煤柱的宽度为7.83 m。其次,应用数值模拟的方法系统地分析了宽度分别为4、6、8、10、12、15、20 m时,在两次采动影响下巷间煤柱的应力演化、破坏、巷道围岩变形规律;一次采动影响后,随着煤柱宽度增大,髙应力由实体煤向煤柱内转移;给出了最大临界尺寸、最小临界尺寸的定义,并指出巷间窄煤柱宽度应小于最大临界尺寸。综合分析数值模拟研究结果,同时结合理论分析结果及煤柱留设原则,最终确定巷间煤柱宽度为8 m。最后,通过现场工程实践验证了所确定的巷间煤柱宽度的合理性。研究结果对类似条件下综放双巷布置工作面巷间煤柱宽度的确定具有参考意义。

关键词：巷间煤柱厚煤层综放工作面双巷布置

Fe含量对粉末冶金Cu-Fe合金显微组织与性能的影响

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Transactions of Nonferrous Metals Society of China 2024年第5期34卷 1571-1587页

作者：张平袁晓波曾梓名滕剑威周芸合杨标标李云平中南大学粉末冶金国家重点实验室长沙410083 Institute for Materials Research Tohoku UniversitySendai 980-8577Japan IMDEA Materials Institute C/Eric Kandel 2GetafeMadrid 28906Spain Department of Materials Science Polytechnic University of Madrid/Universidad Politécnica de MadridE.T.S.de Ingenieros de CaminosMadrid 28040Spain

研究Fe含量对粉末冶金Cu-Fe合金显微组织及性能的影响。采用电火花等离子烧结、冷轧以及时效处理工艺制备4种不同铁含量(5%、10%、20%和40%,质量分数)的Cu-Fe合金。研究结果表明,随着Fe含量从5%(质量分数)增加到40%(质量分数),Fe相由离... 详细信息

研究Fe含量对粉末冶金Cu-Fe合金显微组织及性能的影响。采用电火花等离子烧结、冷轧以及时效处理工艺制备4种不同铁含量(5%、10%、20%和40%,质量分数)的Cu-Fe合金。研究结果表明,随着Fe含量从5%(质量分数)增加到40%(质量分数),Fe相由离散球形分布演变为连续交错分布,Fe相尺寸从0.29μm增加到1.20μm;时效态的Cu-Fe合金的屈服强度从411.5 MPa提高到788.8 MPa,电导率从62.5%(IACS)降低到42.0%(IACS)。在以上结果的基础上,提出一种混合法则计算Cu基体、初级Fe相和次级Fe相对屈服强度的贡献,可较好地预测Fe含量高于10%(质量分数)合金的力学性能。

关键词：铜铁合金粉末冶金快速凝固力学性能强度计算