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Influence of tool pin profile and rotational speed on the formation of friction stir welding zone in AZ31 magnesium alloy

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Journal of magnesium and Alloys 2018年第2期6卷 205-213页

作者： dr.S.Ugender department of Mechanical Engineering Holy Mary Institute of Technology and ScienceHyderabadIndia-501301

In this investigation,the effect of friction stir welding(FSW)parameters such as tool pin profiles,rotational speed and welding speed on the mechanical properties of tensile strength,hardness and impact energy of magnesium alloy AZ31 was *** experiments were carried out as per Taguchi parametric design concepts and an L9 orthogonal array was used to study the influence of various combinations of process *** optimization technique,ANOVA,was used to determine the optimum levels and to find the significance of each process *** results indicate that rotational speed(RS)and transverse speed(TS)are the most significant factors,followed by tool pin profile(PF),in deciding the mechanical properties of friction stir welded magnesium *** addition,mathematical models were developed to establish relationship between different process variables and mechanical properties.

关键词： Friction stir welding Tool pin profile Mechanical properties,Taguchi orthogonal array,Analysis of variance(ANOVA)

血清CysC和CTRP9水平对2型糖尿病视网膜病变的诊断价值

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中华实验眼科杂志 2024年第3期42卷 271-278页

作者：张书景海霞刘勤马建军白惠玲甘肃省人民医院眼科兰州730000 甘肃中医药大学第一临床医学院兰州730000

目的探讨血清胱抑素C(CysC)和C1q肿瘤坏死因子相关蛋白9(CTRP9)水平对2型糖尿病患者糖尿病视网膜病变(dr)及糖尿病黄斑水肿(DME)的诊断价值。方法采用横断面研究方法,纳入2021年4月至2022年4月在甘肃省人民医院就诊的135例2型糖尿病患者... 详细信息

目的探讨血清胱抑素C(CysC)和C1q肿瘤坏死因子相关蛋白9(CTRP9)水平对2型糖尿病患者糖尿病视网膜病变(dr)及糖尿病黄斑水肿(DME)的诊断价值。方法采用横断面研究方法,纳入2021年4月至2022年4月在甘肃省人民医院就诊的135例2型糖尿病患者,年龄45~75岁,按照dr分级标准将患者分为无dr(Ndr)组、非增生型dr(NPdr)组和增生型dr(Pdr)组,每组45例。根据有无DME将NPdr组和Pdr组患者分为DME组51例和非DME组39例。另选取45名健康体检者作为正常对照组。采集受检者空腹外周静脉血,检测血清中糖化血红蛋白、空腹血糖、三酰甘油、总胆固醇、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇、CysC和CTRP9水平。比较各组CysC和CTRP9表达差异。采用多因素Logistic回归分析模型评估dr及DME的独立影响因素,采用受试者工作特征(ROC)曲线评价血清CysC和CTRP9对dr及DME的诊断价值。结果正常对照组、Ndr组、NPdr组和Pdr组血清CysC水平分别为0.74(0.67,0.83)、1.03(0.85,1.22)、1.40(0.98,1.63)和1.66(1.31,1.85)mg/L,呈逐渐升高趋势;CTRP9水平分别为(136.90±14.95)、(120.23±16.31)、(109.50±14.71)和(90.99±13.88)pg/ml,呈逐渐降低趋势;组间总体比较差异均有统计学意义(Z=89.430,Pdr发生的独立危险因素,CTRP9水平(OR=0.937,95%CI:0.908~0.966,Pdr发生的保护因素;血清CTRP9水平(OR=0.838,95%CI:0.778~0.903,Pdr的ROC曲线下面积(AUC)分别为0.798、0.802和0.870,血清CysC和CTRP9水平截断值分别取1.34 mg/L和110.12 pg/ml时可获得最佳诊断效能;其单独及联合诊断dr患者并发DME的AUC分别为0.682、0.923和0.923,血清CTRP9水平的截断值取104.68 pg/ml时可获得最佳诊断效能。结论血清CysC水平升高及CTRP9水平降低是2型糖尿病患者发生dr的危险因素,血清CTRP9水平降低为dr患者发生DME的危险因素之一。

关键词：糖尿病糖尿病视网膜病变黄斑水肿胱抑素C C1q肿瘤坏死因子相关蛋白9 诊断

Genetic Algorithm Based Smart Grid System for Distributed Renewable Energy Sources

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Computer Systems Science & Engineering 2023年第4期45卷 819-837页

作者： M.Mythreyee dr A.Nalini department of Electrical and Electronics Engineering Dr.M.G.R.Educational and Research InstituteMaduravoyalChennai600095TamilnaduIndia

This work presents the smart grid system for distributed Renewable Energy Sources(RES)with control *** hybrid MicroGrids(MG)are trending in small-scale power systems that involve distributed generations,power storage,and various *** of solar are implemented with boost converter using maximum Power Point Tracking(MPPT)with perturb and observe technique to track the maximum ***,the wind system is designed by permanent magnet synchronous generator that includes boost converter with MPPT *** battery is also employed with a Direct Current(DC)-DC bidirectional converter,and has a state of *** maTLAB/Simulink Simscape software is used to design the proposed *** switching element of all converters is metal oxide semiconductor field effect *** hybrid system is controlled by a voltage source controller using Proportional Integral derivative(PID)-Genetic Algorithm(GA),and inductors-capacitors filter is used to reduce the system’s ***,smart meters are used for monitoring purposes in residential *** paper analyses the performances of the MG against various scenarios.

关键词： Solar photovoltaic wind battery converter voltage sources controller microgrid

Relationship between autoimmune hepatitis and HLa.dr4 and drβ allelic sequences in the third hypervariable region in Chinese

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World Journal of Gastroenterology 2001年第5期7卷 718-721页

作者： Xiong ma de-Kai Qiu Shanghai Institute of Digestive Disease,Shanghai Renji Hospital,Shanghai Second Medical University,Shanghai 200001,China Shanghai Institute of Digestive Disease Shanghai Second Medical University Affiliated Renji Hospital 145 Shandong Zhonglu Shanghai 200001 China. Xiongma@***

AIM To analyze the association of HLa.drBl with autoimmune hepatitis (AIH) in patients from China.``METHODS In .32 patients and 45 healthy controls,polymerase chain reaction amplification with sequencespecific primers (PCR-SSP) was performed to examine the association of certain alleles or polymorphic sequences of HLa.drB1 with AIH.``RESULTS HLa.drB1 typing by PCFLSSP showed that dr4had a significantly increased frequency among patients with AIH versus healthy control (46.9% versus 20.8%;relative risk 3.35, P=0.014). In subtypes of dr4, there was a trend of increase in the gene frequency of drB10405 in patients with AIH versus healthy controls (21.9%vs 6.3%, P=0.04, but Pc 0.08). In addition, asignificant increase was found in the alleles frequency encoding QRRAA from the third hyperpolymorphic region of dr4 in the patients with AIH (86.7% of dr4 positive patients vs 40.0% in dr4 positive controls, P 0.016, Pc =0.028. RR 9.75).``CONCLUSION AIH in Chinese is associated with HLAdr4. There is a relationship between QRRAA sequence within the third hyperpolymorphic region of the drB allele and AIH in Chinese.

关键词： hepatitis, autoimmune/immunology HLa.dr antigen/ genetics alleles sequence analysis polymerase chain reaction

Wide hybridization:engineering the next leap in wheat yield

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Journal of Genetics and Genomics 2009年第9期36卷 509-510页

作者： dr. Daowen Wang Institute of Genetics and developmental Biology Chinese Academy of Sciences Beijing 100101 China

Wide hybridization and chromosome engineering constitute an active and important area of plant biology research. The insights obtained in this field have contributed significantly to the understanding of the structure and function of plant chromosomes and genomes, and to the genetic improvement of many agricultural crops. Owing to well defined genomic relationships, clearly visible metaphase chromosomes, and relatively high interspecific and intergeneric crossability, wheat and related Triticeae species form ideal experimental systems for conducting wide hybridization and chromosome engineering studies （Sears, 1972, 1981; Singh and Jauhar, 2006）. Pioneering investigations have demonstrated that the entire genome or chromatin from Triticeae relatives can be transferred into wheat genome through chromosome engineering （re- viewed by Qi et al., 2007）.

关键词： no English key word

羟苯磺酸钙辅助532 nm眼底激光对糖尿病视网膜病变患者黄斑厚度及视网膜新生血管荧光素渗漏面积的影响

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反射疗法与康复医学 2024年第9期5卷 119-122页

作者：孙海华马楠烟台海港医院有限公司眼科山东烟台264000

目的探讨羟苯磺酸钙辅助532 nm眼底激光对糖尿病视网膜病变(dr)患者的影响。方法以2020年5月—2023年5月于我院门诊和住院治疗的150例dr患者为研究对象,按照随机数字表法将其分为对照组和观察组,各75例。对照组实施532 nm眼底激光治疗,... 详细信息

目的探讨羟苯磺酸钙辅助532 nm眼底激光对糖尿病视网膜病变(dr)患者的影响。方法以2020年5月—2023年5月于我院门诊和住院治疗的150例dr患者为研究对象,按照随机数字表法将其分为对照组和观察组,各75例。对照组实施532 nm眼底激光治疗,观察组在对照且基础上加用羟苯磺酸钙治疗。比较两组视力水平、视网膜新生血管荧光素渗漏面积、黄斑厚度、生活质量、并发症发生情况。结果治疗后,观察组视网膜新生血管荧光素渗漏面积(2.78±0.55)mm^(2)小于对照组,黄斑厚度(305.12±38.46)μm薄于对照组,视力水平(0.75±0.21)及世界卫生组织生存质量测定量表中的环境领域评分(79.88±6.42)分、心理领域评分(80.66±6.97)分、社会关系领域评分(82.13±6.73)分、生理领域评分(79.84±6.63)分均高于对照组,组间差异有统计学意义(P0.05)。结论羟苯磺酸钙辅助532 nm眼底激光治疗,可明显缩减黄斑厚度,减小渗漏面积,有助于视力改善,且安全性高。

关键词：糖尿病视网膜病变 532 nm眼底激光羟苯磺酸钙视网膜新生血管荧光素渗漏面积黄斑厚度

Integral representation of M-band filters of Daubechies type

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Chinese Science Bulletin 1997年第10期42卷 803-807页

作者： Huang, dr Sun, QY Zhang, ZY Center for mathematical Sciences Zhejiang University Hangzhou China

FOR natural integers M≥2 and N≥1,M-band filter _N^MH(ξ)of Daubechies type is a trigono-metric polynomial _N^MH(ξ)with real coefficients such

关键词： filter vanishing moment integral representation.

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虚拟电厂下灵活资源多时间尺度调频控制

电力系统自动化 2024年第18期48卷 76-86页

作者：莫理莉兰峻焜周亮叶萌马力陈皓勇华南理工大学电力学院广东省广州市510640 华南理工大学建筑设计研究院有限公司广东省广州市510640 广东电网有限责任公司广州供电局广东省广州市510600

随着能源结构转型的推进,可再生能源的使用逐渐增加,仅依靠传统机组调节频率偏差难以满足需求。因此,为了解决此问题,考虑利用分布式资源(dr)参与调频辅助服务,dr主要考虑空调、电动汽车充电桩以及储能。首先,考虑了dr的特性和满意度评... 详细信息

随着能源结构转型的推进,可再生能源的使用逐渐增加,仅依靠传统机组调节频率偏差难以满足需求。因此,为了解决此问题,考虑利用分布式资源(dr)参与调频辅助服务,dr主要考虑空调、电动汽车充电桩以及储能。首先,考虑了dr的特性和满意度评价方法;然后,基于状态势博弈理论对dr进行协调控制,将dr集中起来使其对外呈现为一个整体参与调频辅助服务;最后,通过算例仿真证明了该方案下对dr聚合并协调控制参与调频辅助服务的可行性和有效性,并对多时间尺度下储能、电动汽车充电桩以及可控负荷参与快速调频进行了验证。

关键词：虚拟电厂分布式资源灵活资源协调控制多时间尺度控制调频辅助服务状态势博弈

An Automated Brain Image Analysis System for Brain Cancer using Shearlets

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Computer Systems Science & Engineering 2022年第1期40卷 299-312页

作者： R.Muthaiyan dr M.malleswaran department of Electronics and Communication Engineering University College of Engineering ThirukkuvalaiTamilnadu610204India department of Electronics and Communication Engineering University College of Engineering KancheepuramKancheepuram631552India

In this paper,an Automated Brain Image Analysis(ABIA)system that classifies the magnetic Resonance Imaging(MRI)of human brain is *** classification of MRI images into normal or low grade or high grade plays a vital role for the early *** Non-Subsampled Shearlet Transform(NSST)that captures more visual information than conventional wavelet transforms is employed for feature *** the feature space of NSST is very high,a statistical t-test is applied to select the dominant directional sub-bands at each level of NSST decomposition based on sub-band energies.A combination of features that includes Gray Level Co-occurrence matrix(GLCM)based features,Histograms of Positive Shearlet Coefficients(HPSC),and Histograms of Negative Shearlet Coefficients(HNSC)are *** combined feature set is utilized in the classification phase where a hybrid approach is designed with three classifiers;k-Nearest Neighbor(kNN),Naive Bayes(NB)and Support Vector machine(SVM)*** output of individual trained classifiers for a testing input is hybridized to take a final *** quantitative results of ABIA system on Repository of Molecular Brain Neoplasia Data(REMBRANDT)database show the overall improved performance in comparison with a single classifier model with accuracy of 99% for normal/abnormal classification and 98% for low and high risk classification.

关键词： Brain image analysis wavelets Shearlet multi-scale analysis hybrid classification