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Real-time grain breakage sensing for rice combine harvesters using machine vision technology

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International Journal of Agricultural and Biological Engineering 2020年第3期13卷 194-199页

作者： Jin Chen yi lian Rong Zou Shuai Zhang Xiaobo Ning Mengna Han College of Mechanical Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

Breakage rate is one of the most important indicators to evaluate the harvesting performance of a combine *** is affected by operating parameters of a combine such as feeding rate,the peripheral speed of the threshing cylinder and concave clearance,and shows complex non-linear ***-time acquisition of the breakage rate is an effective way to find the correlation of *** addition,real-time monitoring of the breakage rate can help the driver optimize and adjust the operating parameters of a combine harvester to avoid the breakage rate exceeding the *** this study,a real-time monitoring method for the grain breakage rate of the rice combine harvester based on machine vision was *** structure of the sampling device was designed to obtain rice kernel images of high quality in the harvesting *** to the working characteristics of the combine,the illumination and installation of the light source were optimized,and the lateral lighting system was constructed.A two-step method of“color training-verification”was applied to identify the whole and broken *** the first step,the local threshold algorithm was used to get the edge of kernel particles in a few training images with binary transformation,extract the color spectrum of each particle in color-space HSL and output the recognition model *** second step was to verify the recognition accuracy and the breakage rate monitoring accuracy through grabbing and processing images in the *** experiments of about 2300 particles showed that the recognition accuracy of 96%was attained,and the monitoring values of breakage rate and the true artificial monitoring values had good trend *** monitoring device of grain breakage rate based on machine vision can provide technical supports for the intellectualization of combine harvester.

关键词： combine harvester breakage rate monitoring sampling box structure machine vision color classification

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车辆发动机舱非金属零部件热老化寿命研究

汽车工程学报 2024年第5期14卷 888-897页

作者：欧阳俊袁侠义肖露彭家燕段炼广州汽车集团股份有限公司汽车工程研究院广州511434

热氧老化是发动机舱非金属零部件主要热失效模式之一,传统的整车热管理开发流程大多仅关注零部件的最高工作温度,不能有效地预测零部件生命周期内的热衰退表现。基于中国市场的气候条件和车辆道路行驶大数据,建立了一套整车热老化等效... 详细信息

热氧老化是发动机舱非金属零部件主要热失效模式之一,传统的整车热管理开发流程大多仅关注零部件的最高工作温度,不能有效地预测零部件生命周期内的热衰退表现。基于中国市场的气候条件和车辆道路行驶大数据,建立了一套整车热老化等效行驶工况和零部件热老化寿命评估方法。采用该方法对某车型发动机悬置橡胶衬套的热老化寿命进行了评估,发现改善橡胶材料的配方可以提高其热老化寿命至约3倍,悬置橡胶衬套的实际工作温度在原有基础上升高10℃,其热老化寿命减少约50.0%。对悬置橡胶衬套的传热路径进行了分析,发现可以通过优化冷却风扇尾流以及降低发动机本体与悬置橡胶衬套之间的热传导来改善橡胶衬套的实际工作温度,从而提高其热老化寿命。

关键词：发动机舱热老化寿命等效行驶工况温度分布热衰退

Homotopy Solution for Stagnation-Point Flow

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Communications in theoretical Physics 2012年第2期57卷 290-294页

作者： t.Hayat Ansa Rafique M.y.Malik S.A.Shehzad S.Obaidat Department of Mathematics Quaid-i-Azam University 45320Islamabad 44000Pakistan Department of Mathematics College of SciencesKing Saud UniversityP.O.Box 2455Riyadh 1145Saudi Arabia

this article reports the homotopy solution for stagnation point flow of a non-Newtonian fluid. An incompressible second grade fluid impinges on the wall either orthogonally or obliquely. the resulting nonlinear problems have been solved by a homotopy analysis method （HAM）. Convergence of the series solutions is checked. Such solutions are compared with the numerical solutions presented in a study lint. J. Non-Linear Mech. 43 （2008） 941]. Excellent agreement is noted between the numerical and series solutions.

关键词： Homotopy solution second-grade fluid nonlinear analysis

the prognosis of trabeculectomy in primary angleclosure glaucoma patients

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International Journal of Ophthalmology(English edition) 2019年第1期12卷 66-72页

作者： Jun-Dong Zhu Li-lian Xie Zhi-yuan Li Xiao-He Lu Department of Ophthalmology Zhujiang Hospital of Southern Medical University Department of Ophthalmology the First People’s Hospital of Chenzhou CitySouthern Medical University

AIM: to evaluate whether the level of thrombospondin-1(tSP-1) in aqueous humor can predict the prognosis of trabeculectomy in patients with primary angle-closure glaucoma(PACG). MEtHODS: this case-control study involved 26 patients with PACG who experienced a failed trabeculectomy(case group) and 78 age-and sex-matched patients with PACG who underwent successful trabeculectomy(control group). Aqueous humor was collected at the time of trabeculectomy and tested for tSP-1 and tGF-β2 levels with an enzyme-linked immunosorbent assay method. Logistic regression modeling was used to assess the risk factors for failed trabeculectomy. RESULtS: the mean tSP-1 aqueous concentrations were significantly higher in the case group(20.67±9.79 ng/mL) than the control group(5.17±2.29 ng/mL)(Pthe transforming growth factor-β2(tGF-β2) aqueous concentrations were significantly different between the case and control group, at 3633.25 and 1090.24 pg/mL, respectively(Ptic regression analysis revealed tSP-1 level as an independent risk factor for a failed trabeculectomy(OR=3.540; 95%CI=1.092-11.482). CONCLUSION: the aqueous humor tSP-1 and tGF-β2 levels are higher in PACG eyes with failed trabeculectomy than with successful trabeculectomy at one year. the aqueous humor tSP-1 level is an independent risk factor associated with failed trabeculectomy.

关键词： thrombospondin-1 prognosis primary angleclosure glaucoma

the oscillation-outbreaks characteristic of the COVID-19 pandemic

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National Science Review 2021年第8期8卷 144-146页

作者： Jianping Huang Xiaoyue Liu Li Zhang yingjie Zhao Danfeng Wang Jinfeng Gao Xinbo lian Chuwei Liu Collaborative Innovation Center for Western Ecological Safety (CIWES) Lanzhou University

SARS-CoV-2 has been circulating in the human population for more than a year and has caused over 150 million cases globally as of 1 May 2021. Although a lot of regions have relied on measures such as social distancing, contact tracing and quarantine to slow its spread [1],multidisciplinary researchers are actively engaged in understanding the dynamic of its transmission.

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Metabolic properties of chicken embryonic stem cells

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Science China(Life Sciences) 2010年第9期53卷 1073-1084页

作者： LI Jia ZHANG BaoLu HAN HongBing CAO ZhiCheng lian ZhengXing LI Ning State Key Laboratory of Agrobiotechnology China Agricultural UniversityBeijing 100194China College of Animal Science&technology China Agricultural UniversityBeijing 100194China

Cellular energy metabolism correlates with cell fate,but the metabolic properties of chicken embryonic stem (chES) cells are poorly *** a previously established chES cell model and electron microscopy (EM),we found that undifferentiated chES cells stored ***,undifferentiated chES cells expressed lower levels of glucose transporter 1 (GLUt1) and phosphofructokinase (PFK) mRNAs but higher levels of hexokinase 1 (HK1) and glycogen synthase (GyS) mRNAs compared with control primary chicken embryonic fibroblast (CEF) cells,suggesting that chES cells direct glucose flux towards the glycogenic ***,we demonstrated that undifferentiated chES cells block gluconeogenic outflow and impede the accumulation of glucose-6-phosphate (G6P) from this pathway,as evidenced by the barely detectable levels of pyruvate carboxylase (PCX) and mitochondrial phosphoenolpyruvate carboxykinase (PCK2) ***,cell death occurred in undifferentiated chES cells as shown by Hoechst 33342 and propidium iodide (PI) double staining,but it could be rescued by exogenous ***,we found that differentiated chES cells decreased the glycogen reserve through the use of PAS ***,differentiated chES cells expressed higher levels of GLUt1,HK1 and PFK mRNAs,while the level of GyS mRNA remained similar in control CEF *** data indicate that undifferentiated chES cells continue to synthesize glycogen from glucose at the expense of G6P,while differentiated chES cells have a decreased glycogen reserve,which suggests that the amount of glycogen is indicative of the chES cell state.

关键词： chicken embryonic stem cell energy metabolism glycogen cell fate glucose-6-phosphate

2022年贵州省食品及病人来源单增李斯特菌的抗生素敏感性及分子特征分析

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中国人兽共患病学报 2024年第7期40卷 613-619页

作者：周倩郑联向婧姝黄靖宇朱姝张德罗信旭周藜贵州省疾病预防控制中心贵阳550004 贵州医科大学公共卫生与健康学院环境污染与疾病监控教育部重点实验室贵阳561113

目的了解2022年贵州省29株食品及病人来源的单核细胞增生李斯特氏菌(单增李斯特菌)的血清型、基因型、耐药及毒力基因等遗传特征。方法对贵州省2022年食品微生物及食源性疾病监测中分离的29株单增李斯特菌采用微量肉汤稀释法测定菌株对... 详细信息

目的了解2022年贵州省29株食品及病人来源的单核细胞增生李斯特氏菌(单增李斯特菌)的血清型、基因型、耐药及毒力基因等遗传特征。方法对贵州省2022年食品微生物及食源性疾病监测中分离的29株单增李斯特菌采用微量肉汤稀释法测定菌株对8种抗生素的最小抑菌浓度(MIC)值,并哌全基因组测序及生物信息学分析,包括谱系、血清群、序列分析(St型)、克隆群(CC型)、耐药基因、毒力基因等。结果29株单增李斯特菌对8种抗生素均不耐药;对耐药基因分析发现在29株菌中检出6种耐药基因,全部菌株均携带fosX、mprE、lin、norB;29株菌分属于2个谱系(Ⅰ、Ⅱ),17株菌属于谱系Ⅱ,12株菌属于谱系Ⅰ;分为13种St型,其中St8为优势型别,占31.03%(9/29株),其次为St619、St121型别各3株;分为4个血清群,血清群1/2a、3a有15株,血清群1/2b、3b、7有11株,血清群1/2c、3c有2株,血清群4b、4d、4e有1株;分为12个CC型,以及1个未分CC型的St2348,其中CC8为优势CC型,有9株菌占27.59%(8/29株),分属于23种cgMLSt型,每型包括1~3株菌。共发现25种毒力基因,29株菌均携带毒力岛LIPI-1,其中3株菌未携带actA基因,缺失率10.34%;有7株菌均携带毒力岛LIPI-3的8个基因,其余22株菌未携带;所有菌株携带多种内化素毒力基因。结论贵州省食源性单增李斯特菌耐药水平低,携带较多的毒力基因,血清群与分子型别表现出遗传多样性,应加强对单增李斯特菌的持续监测。

关键词：单增李斯特菌全基因组测序贵州省毒力基因

基于网络药理学的山药降血糖活性成分筛选及其活性验证

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农产品加工 2024年第15期 52-55页

作者：徐元苟美玲连尧王丹罗晨露成都师范学院化学与生命科学学院四川成都611130

运用虚拟筛选和分子对接方法筛选出山药治疗糖尿病的活性成分并进行药效学试验验证,揭示山药药效物质基础。把山药中所含已知的12种化学成分构建为分子库,与根据其功效确定的各作用靶点模型进行虚拟对接,再考查筛选出的多靶点活性成分... 详细信息

运用虚拟筛选和分子对接方法筛选出山药治疗糖尿病的活性成分并进行药效学试验验证,揭示山药药效物质基础。把山药中所含已知的12种化学成分构建为分子库,与根据其功效确定的各作用靶点模型进行虚拟对接,再考查筛选出的多靶点活性成分对四氧嘧啶糖尿病动物模型的影响。结果表明,①对11β-羟基类固醇脱氢酶(11β-HSD1)、环氧合酶(PtGS2)、丝氨酸蛋白酶(PRSS1)有理论活性的成分远多于其他靶点;②部分成分对多个靶点均显示较强的理论活性;③药效学试验结果表明,虚拟筛选所确定的活性成分中薯蓣皂苷元(Diosgenin)、豆甾醇(Stigmasterol)、菜油甾醇(Brassinosteroids)、熊果苷对硝酸四氧嘧啶糖尿病动物模型有明显影响。为阐释食药同源物质药效物质基础提供了新的视角和快捷途径。

关键词：山药糖尿病活性靶点虚拟筛选药效学试验

Electrochemical behavior of the V（ Ⅳ ）／V（ Ⅴ ）couple in sulfuric acid medium

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电池 2003年第6期33卷 339-341页

作者： S.Iwasa y.Wei B.Fang t.Arai M.Kumagai InstituteofResearch＆Innovation 1201TakadaKashiwaChiba277-0861Japan

the electrochemical behavior of the V( Ⅳ )/V( Ⅴ ) redox couple at a glassy carbon electrode was investigated. Cyclic voltammetry(CV) results indicated that electrode process of the V( Ⅳ )/V( Ⅴ ) couple was electrochemically quasi-reversible with a rate constant of 8 × 10^-4 cm/S . Increasing concentration of sulfuric acid was electrochemically favourable for the V( Ⅳ )/V( Ⅴ )couple while elevated temperature was unfavourable for this system. Constant-current electrolysis results showed that current efficiency of more than 95 % could be achieved, which indicated that the V( Ⅳ )/V( Ⅴ ) couple had excellent electrolytic performance and was suitable for the application as the anolyte of redox flow batteries.

关键词：全钒氧化还原电池 RFB 可充电电池循环伏安法电解液阳极