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Turbo-shaft engine adaptive neural network control based on nonlinear state space equation

Chinese Journal of Aeronautics 2024年第4期37卷 493-507页

作者： Ziyu GU Qiuhong LI Shuwei PANG wenxiang ZHOU Jichang WU Chenyang zhang Jiangsu Province Key Laboratory of Aerospace Power System Nanjing University of Aeronautics and AstronauticsNanjing 210016China AECC Hunan Aviation Powerplant Research Institute Zhuzhou 412002China

Intelligent Adaptive Control(AC) has remarkable advantages in the control system design of aero-engine which has strong nonlinearity and uncertainty. Inspired by the Nonlinear Autoregressive Moving Average(NARMA)-L2 adaptive control, a novel Nonlinear State Space Equation(NSSE) based Adaptive neural network Control(NSSE-AC) method is proposed for the turbo-shaft engine control system design. The proposed NSSE model is derived from a special neural network with an extra layer, and the rotor speed of the gas turbine is taken as the main state variable which makes the NSSE model be able to capture the system dynamic better than the NARMA-L2 model. A hybrid Recursive Least-Square and Levenberg-Marquardt(RLS-LM) algorithm is advanced to perform the online learning of the neural network, which further enhances both the accuracy of the NSSE model and the performance of the adaptive controller. The feedback correction is also utilized in the NSSE-AC system to eliminate the steady-state tracking error. Simulation results show that, compared with the NARMA-L2 model, the NSSE model of the turboshaft engine is more accurate. The maximum modeling error is decreased from 5.92% to 0.97%when the LM algorithm is introduced to optimize the neural network parameters. The NSSE-AC method can not only achieve a better main control loop performance than the traditional controller but also limit all the constraint parameters efficiently with quick and accurate switching responses even if component degradation exists. Thus, the effectiveness of the NSSE-AC method is validated.

关键词： Adaptive control systems Turbo-shaft engine Neural network Nonlinear state space equation NARMA-L2

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黄体期长方案与拮抗剂方案在首次拮抗剂失败后PCOS患者中的应用比较

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安徽医科大学学报 2024年第6期59卷 976-982页

作者：王田娟王超邢琼徐玉萍张文香周平许孝凤魏兆莲曹云霞安徽医科大学第一附属医院妇产科合肥230032 国家卫生健康委配子及生殖道异常研究重点实验室合肥230032 出生人口健康教育部重点实验室合肥230032

目的探讨首次拮抗剂治疗失败的多囊卵巢综合征(PCOS)患者再次超促排卵时分别采用黄体期长方案和拮抗剂方案诱导排卵的临床效果及妊娠结局的优劣。方法检索首次采用拮抗剂方案行IVF/ICSI-ET助孕失败后再次超促排卵的PCOS患者163例,根据... 详细信息

目的探讨首次拮抗剂治疗失败的多囊卵巢综合征(PCOS)患者再次超促排卵时分别采用黄体期长方案和拮抗剂方案诱导排卵的临床效果及妊娠结局的优劣。方法检索首次采用拮抗剂方案行IVF/ICSI-ET助孕失败后再次超促排卵的PCOS患者163例,根据第二次超促排卵方案,分为黄体期长方案组(共95例)和拮抗剂方案组(共68例)。回顾性分析比较两组患者的基础临床资料、临床及实验室指标及妊娠结局。结果①两组患者的基础临床指标除了LH,其他指标差异均无统计学意义。②黄体期长方案组患者自身超排卵对比,促性腺激素(Gn)启动剂量、Gn总天数、Gn总使用量、hCG注射日雌二醇(E_(2))值、获卵数、卵子成熟率、2PN受精数、2PN卵裂数、囊胚形成率、优质囊胚形成率显著高于首次拮抗剂周期(P<0.05)。拮抗剂方案组患者自身超排卵对比也观察到类似改善。③两组第二次超促排卵周期比较,黄体期长方案组Gn总天数、总用量、总费用较高(P<0.05),而hCG注射日E_(2)及LH水平、卵子成熟率显著低于拮抗剂方案(P<0.05),但两组间获卵数、2PN受精数、2PN卵裂数、囊胚形成率、OHSS率差异无统计学意义。④两组第二次超促排卵新鲜移植周期比较,黄体期长方案新鲜移植率、种植率、临床妊娠率及活产率略高,但差异无统计学意义。首次解冻周期的妊娠结局比较,拮抗剂组的生化妊娠率、临床妊娠率高于黄体期长方案组(P<0.05),但着床率、活产率、新生儿胎龄及出生体质量差异无统计学意义。结论对于首次拮抗剂方案治疗失败的患者,适当增加Gn启动剂量及用量,两种方案均能获得满意的妊娠结局。相较于黄体期长方案,再次使用拮抗剂方案保持了其优势,包括治疗周期短、成本低、患者依从性好。

关键词：多囊卵巢综合征体外受精黄体期长方案拮抗剂方案控制性促排卵

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提高120 t精炼钢包一次包龄的生产实践

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工业炉 2024年第3期46卷 56-59+69页

作者：张响张文祥武晓阳姜名贞李硕李双武唐山钢铁集团有限责任公司

针对钢包一次包龄低的问题，通过对钢包各部位砖型损毁机理进行分析，提出了一系列改进措施，包括：钢包各部位耐材材质优化；钢包重点部位砌筑防护；使用高性能、长寿命透气砖；优化钢包周转节奏等，并在120 t精炼钢包中进行实践验证... 详细信息

针对钢包一次包龄低的问题，通过对钢包各部位砖型损毁机理进行分析，提出了一系列改进措施，包括：钢包各部位耐材材质优化；钢包重点部位砌筑防护；使用高性能、长寿命透气砖；优化钢包周转节奏等，并在120 t精炼钢包中进行实践验证。结果表明：通过以上改进措施，钢包平均一次包龄由之前的42.35炉提高到62.77炉，最高包龄达到了72炉，耐材和钢包投入成本大幅下降，且对生产组织稳定运行起到了极大的促进作用。

关键词：精炼钢包包龄耐材优化周转生产实践

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Selection and Characterization of a Novel Photoperiod-Sensitive Male Sterile Line in Upland Cotton

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Journal of Integrative Plant Biology 2013年第7期55卷 608-618页

作者： Jianhui Ma Hengling Wei Ji Liu Meizhen Song Chaoyou Pang Long Wang wenxiang zhang Shuli Fan Shuxun Yu State Key Laboratory of Cotton Biology the Institute of Cotton Researchthe Chinese Academy of Agricultural Sciences College of Life Sciences Henan Normal University College of Agronomy Northwest A & F University

Upland cotton （Gossypium hirsutum L.） shows strong heterosis. However, heterosis is not widely utilized owing to the high cost of hybrid seed production. Creation of a photoperiod-sensitive genetic male sterile line could substantially reduce the cost of hybrid seed production in upland cotton. Such a mutant with virescent marker was found by space mutation in near-earth orbit and its traits had been stable after 4 years of selection in Anyang and Sanya, China. This mutant was fertile with an 11-12.5 h photoperiod when the temperature was higher than 21.5 ℃ and was sterile with a 13-14.5 h photoperiod. Genetic analysis indicated that both traits were controlled by a single recessive gene or two closely linked genes. Also, the cytological observations and transcriptome profiling analysis showed that the degradation of pollen grain cytoplasm should be the primary reason why the mutant line were male sterile under long-day conditions.

关键词： Photoperiod-sensitive genetic male sterile sterility mechanism upland cotton virescent marker.

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Research On The Protection Of The Space Environment In China

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Aerospace China 2007年第1期8卷 19-20页

作者： zhang wenxiang

To control the generation of space debris is one of the emphases of space debris study in China. We should understand the significance of the research on the mitigation of space debris from the point of view of the outer space environment protection. This paper briefly introduces the main achievements made in the field of space debris mitigation in China last year and the main ongoing research activities. The ideas for future research on space debris mitigation in China are also Odescribed.

关键词：太空垃圾研究中国空间环境保护消能技术空间碎片缓解方法

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Digital identity,privacy security,and their legal safeguards in the Metaverse

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Security and Safety 2023年第2期2卷 72-85页

作者： Hong Wu wenxiang zhang NingboTech University Ningbo 315100China

The Metaverse is the digitization of the real world,supported by big data,AI,5G,cloud computing,blockchain,encryption algorithm,perception technology,digital twin,virtual engine,and other technologies that interact with human behavior and thoughts in avatars through digital *** the trust problem brought by the avatar depends on the privacy security and authentication technology for individuals using digital identities to enter the *** accomplish personal domination of the avatar,metaverse users need privacy data feeding and emotion *** must be equipped with proprietary algorithms to process and analyze the complex data generated in adaptive interactions,which challenges the privacy security of user data in the *** the significance of different identifiers in personal identity generation while imposing different behavioral regulatory requirements on data processing levels may better balance the relationship between personal privacy security and digital identity protection and data utilization in the *** response to digital identity issues,there is an objective need to establish a unified digital identity authentication system to gain the general trust of ***,the remedies for a right to personality can be applied to the scenario of unlawful infringement of digital identity and privacy security.

关键词： Metaverse Avatar Digital identity Privacy security Privacy data Identity authentication

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糖尿病心肌病大鼠动物模型的构建及评价指标的建立

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中国循证心血管医学杂志 2024年第3期16卷 328-334页

作者：韩佳容张文祥孙龙飞陈鹏德姚蓝新疆医科大学附属中医医院乌鲁木齐830000 新疆医科大学中医学院中药药理教研室乌鲁木齐830057

目的构建糖尿病心肌病大鼠动物模型并建立其评价指标。方法30只SPF级Wistar雄性大鼠按体重随机分为两组,正常组给予常规饲料喂养、模型组给予高糖高脂饲料喂养4周。模型组大鼠禁食12 h腹腔注射链脲佐菌素(STZ)25 mg/kg,尾尖取血检测随... 详细信息

目的构建糖尿病心肌病大鼠动物模型并建立其评价指标。方法30只SPF级Wistar雄性大鼠按体重随机分为两组,正常组给予常规饲料喂养、模型组给予高糖高脂饲料喂养4周。模型组大鼠禁食12 h腹腔注射链脲佐菌素(STZ)25 mg/kg,尾尖取血检测随机血糖值≥16.7 mmol/L判定为2型糖尿病大鼠。实验期间每周记录一次大鼠的体重及血糖值,8周后计算心脏指数,检测各组大鼠的血脂四项指标以及心电图和标志性的心肌酶。Masson和HE染色观察大鼠心肌组织的纤维化程度和形态学变化,并计算心肌胶原容积分数。Western Blot检测大鼠心脏组织中Bax、Bcl-2、Caspase-3、TGF-β1、α-SMA、Collagen-Ⅰ、肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)蛋白表达水平。结果相较于正常组,模型组大鼠血糖值在1~8周显著升高(P<0.05),体重从第3周起显著降低(P<0.05),心脏指数显著增大(P<0.05),心脏电生理指标表现为心率(HR)、QRS间期、ST段波幅和QT间期水平显著升高(P<0.05)。三酰甘油(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、乳酸脱氢酶(LDH)、肌酸激酶同工酶(CK-MB)和丙二醛(MDA)的含量显著升高(P<0.05),高密度脂蛋白胆固醇(HDL-C)和超氧化物歧化酶(SOD)的含量显著降低(P<0.05)。HE染色结果显示模型组大鼠心肌组织中心肌细胞排列紊乱且间隙增大,并伴有炎性细胞浸润。Masson染色显示与正常组相比,模型组大鼠的心肌胶原容积分数显著增大(P<0.05),纤维化严重。模型组大鼠心肌组织中Bax、Caspase-3、TGF-β1、α-SMA、Collagen-Ⅰ、TNF-α、IL-6蛋白的表达水平显著升高(P<0.05),Bcl-2蛋白水平显著降低(P<0.05)。结论高糖高脂饲料喂养4周后,大鼠腹腔注射小剂量STZ 25 mg/kg,继续喂养8周后的Wistar大鼠在一定程度上已出现了类似于人的糖尿病心肌病的临床表现,此法可用于构建糖尿病心肌病动物模型,上述检测指标可用于糖尿病心肌病大鼠模型的评价。

关键词：糖尿病心肌病动物模型评价指标

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Comparison of the graphic and moment methods for analyzing grainsize distributions: A case study for the Chinese inner continental shelf seas

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International Journal of Sediment Research 2022年第6期37卷 729-736页

作者： Gaocong Li Rihong Du Jieping Tang Zhiqiang Li Qiong Xia Benwei Shi Liang Zhou Yang Yang wenxiang zhang Department of Marine Technology Guangdong Ocean University Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) State Key Laboratory for Estuarine and Coastal Research East China Normal University School of Geography Geomatics and Planning Jiangsu Normal University School of Marine Science and Engineering Nanjing Normal University

Sediment grain-size distributions provide key information on sediment sources, transport, and deposition. The Folk and Ward graphic method and the Friedman moment method are generally used for rapid analysis of the qualitative and quantitative properties of sediment samples; whether the two methods yield the same results for any given sediment sample is not yet known. Little research attention has been paid to comparison of the descriptive terms used in both methods, although some work has been done on comparison of the numerical values. In the current study, sediment samples from six areas of the Chinese inner continental seas were investigated. The mean and sorting values obtained using the two methods are well correlated(0.821 ≤ R~2≤ 0.998), but the skewness and kurtosis vary among study areas(0.035 ≤ R~2≤ 0.816), which is consistent with previous studies where R~2 is the coefficient of determination. The two methods yield significant differences for skewness(84.78%-98.04% of samples) and kurtosis(40.59%-67.29% of samples). The main reasons for these differences are variations in the grainsize distribution curves of the sediment samples and differences in the weighting applied to specified cumulative percentile values by the two methods. These results demonstrate that the differences between the two methods should be taken into account when analyzing sedimentary environments and studying historical data.

关键词： Grain-size parameters Graphic method for grain size distribution Moment method for grain size distribution Grain-size descriptive terms China seas

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On-line Chatter Detection Using an Improved Support Vector Machine

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Instrumentation 2019年第2期6卷 2-7页

作者： Changfu LIU wenxiang zhang School of Mechanical Engineering and Automation Northeastern UniwersityShenyang 110819China Shanghai Yu Chen Industrial Co. LtdShanghai 201306China

On-line chatter detection can avoid unstable cutting through monitoring the machining *** order to identify chatter in a timely manner,an improved Support Vector Machine(SVM)is developed in this paper,based on extracted *** the SVM model,the penalty factor(e)and the core parameter(g)have important influence on the classification,more than from Kernel Functions(KFs).Hence,first the classification results are conducted using different *** two methods are presented for exploring the best *** chatter identification results show that the Genetic Algorithm(GA)approach is more suitable for deciding the parameters than the Grid Explore(GE)approach.

关键词： On-line Chatter Detection Support Vector Machine Parameter Optimization Genetic Algorithms

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钢包包龄和安全防护的优化改进与实践

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四川冶金 2024年第4期46卷 44-48页

作者：李健张文祥武晓阳王爱东李学民唐山钢铁集团有限责任公司河北唐山063000

通过对影响钢包包龄和安全性能的因素分析,采取钢包砖耐材材质优化,钢包砌筑重点部位防护,在线钢包耐材残厚精准测量,优化钢包精炼顶渣成份结构,钢包安全防护技术应用等措施提高钢包包龄和安全防护性能。钢包总包龄平均达到了185次,其... 详细信息

通过对影响钢包包龄和安全性能的因素分析,采取钢包砖耐材材质优化,钢包砌筑重点部位防护,在线钢包耐材残厚精准测量,优化钢包精炼顶渣成份结构,钢包安全防护技术应用等措施提高钢包包龄和安全防护性能。钢包总包龄平均达到了185次,其中最高包龄达到202次,较之前平均112次提高了73次,耐材和钢包投入成本均大幅下降。钢包使用事故率由0.6次/万吨钢降低到0.05次/万吨钢以下,为钢包包龄的提升提供了有利保证。

关键词：钢包包龄安全防护优化实践

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