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基于Wiener-Hammerstein模型的一种系统辨识方法

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计量学报 2012年第4期33卷 360-363页

作者：白克强西南科技大学四川绵阳621010

针对工业大系统中Wiener-Hammerstein模型，提出一种新的辨识方法。该方法结合分散辨识对线性系统辨识精度高的优点与混合粒子群优化解决非线性、不可微和多峰值的复杂问题的长处，进行复合控制，并利用计量学中的动态计量方法，建立动... 详细信息

针对工业大系统中Wiener-Hammerstein模型，提出一种新的辨识方法。该方法结合分散辨识对线性系统辨识精度高的优点与混合粒子群优化解决非线性、不可微和多峰值的复杂问题的长处，进行复合控制，并利用计量学中的动态计量方法，建立动态计量仿真模型。仿真研究与实验结果表明，该方法应用在非线性分布参数系统辨识中可有效提高辨识精度。

关键词：计量学工业大系统 Wiener-Hammerstein模型参数分散辨识混合粒子群

Effects of phosphorus limitation on sinking velocities of phytoplankton during summer in the Changjiang River Estuary

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Acta Oceanologica Sinica 2024年第6期43卷 131-141页

作者： Xinchi You qiang Hao Jie Zhu Wei Zhang Haiyan Jin Dewang Li Huanhong Ji Yu ke Feng Zhou Ocean College Zhejiang UniversityZhoushan 316021China State key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310000China key Laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Donghai Laboratory Zhoushan 316021China East China Sea Ecological Center Ministry of Natural ResourcesShanghai 201206China key Laboratory of Marine Ecological Monitoring and Restoration Technologies Ministry of Natural ResourcesShanghai 201206China Observation and Research Station of Yangtze River Delta Marine Ecosystems Ministry of Natural ResourcesZhoushan 316021China

The sinking of phytoplankton is critical to organic matter transportation in the ocean and it is an essential process for the formation of coastal hypoxic *** study was based on a field investigation conducted during the summer of 2022 in the Changjiang River(Yangtze River) Estuary(CJE) and its adjacent *** settling column method was employed to measure the sinking velocity(SV) of different size fractions of phytoplankton at the surface of the sea and to analyze their environmental control *** findings reveal significant spatial variation in phytoplankton SV(-0.55-2.41 m/d) within the ***-speed sinking was predominantly observed in phosphate-depleted regions beyond the CJE *** the same time,an upward trend was more commonly observed in the phosphate-rich regions near the CJE *** SV ranges for different sizefractionated phytoplankton,including micro-(>20 μm),nano-(2-20 μm),and picophytoplankton(0.7-2 μm),were-0.50-4.74 m/d,-1.04-1.59 m/d,and-1.24-1.65 m/d,*** analysis revealed a significant negative correlation between SV and dissolved inorganic phosphorus(DIP),implying that the influence of DIP contributes to *** variations in phytoplankton alkaline phosphatase activity suggested a significant increase in SV across all size fractions in the event of phosphorus *** communities with limited photo synthetic capacity(maximum photochemical efficience,Fv/Fm ked decrease in SV following phosphate *** findings suggest that phosphorus limitation is the primary driver of elevated SV in the *** study enhances the comprehension of the potential mechanisms underlying hypoxic zone formation in the CJE,providing no

关键词： phytoplankton sinking velocity Changjiang River Estuary phosphorus limitation alkaline phosphatase

A new insight into LPSO phase transformation and mechanical properties uniformity of large-scale Mg-Gd-Y-Zn-Zr alloy prepared by multi-pass friction stir processing

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Journal of Magnesium and Alloys 2024年第5期12卷 2041-2056页

作者： Xiaohu Guan Wen Wang Ting Zhang Pai Peng qiang Liu Peng Han ke Qiao Jun Cai Liqiang Wang Kuaishe Wang School of Metallurgical Engineering National and Local Joint Engineering Research Center for Functional Materials ProcessingXi’an University of Architecture and TechnologyNo.13 Yanta RoadXi’anShaanxi 710055China Xi’an Rare Metal Materials Institute Co.Ltd Xi’an 710016China State key Laboratory of Metal Matrix Composites School of Material Science and EngineeringShanghai Jiao Tong UniversityNo.800 Dongchuan RoadShanghai 200240China

A large-scale fine-grained Mg-Gd-Y-Zn-Zr alloy plate with high strength and ductility was successfully prepared by multi-pass friction stir processing(MFSP)technology in this *** structure of grains and long period stacking ordered(LPSO)phase were characterized,and the mechanical properties uniformity was ***,a quantitative relationship between the microstructure and tensile yield strength was *** results showed that the grains in the processed zone(PZ)and interfacial zone(IZ)were refined from 50μm to 3μm and 4μm,respectively,and numerous original LPSO phases were *** IZ,some block-shaped 18R LPSO phases were transformed into needle-like 14H LPSO phases due to stacking faults and the short-range diffusion of solute *** severe shear deformation in the form of kinetic energy caused profuse stacking fault to be generated and move rapidly,greatly increasing the transformation rate of LPSO *** MFSP,the ultimate tensile strength,yield strength and elongation to failure of the large-scale plate were 367 MPa,305 MPa and 18.0% *** refinement and LPSO phase strengthening were the major strengthening mechanisms for the MFSP *** particularly,the strength of IZ was comparable to that of PZ because the strength contribution of the 14H LPSO phase offsets the lack of grain refinement strengthening in *** result opposes the widely accepted notion that IZ is a weak region in MFSP-prepared large-scale fine-grained plate.

关键词： Friction stir processing Multi-pass Mg-Gd-Y-Zn-Zr alloy LPSO phase transformation Mechanical properties

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多频段共口径遥感信号接收天伺馈系统设计

中国电子科学研究院学报 2024年第5期19卷 410-418页

作者：乔建江霍克强周建寨武织才张冰张少辉王宇哲中国电子科技集团公司第五十四研究所河北石家庄050081

针对多频段遥感信号接收系统对S/C/X/Ku/Ka五频段信号共口径接收、高精度指向和全空域过顶稳定跟踪需求,研制了一种多频段遥感信号接收天伺馈系统,解决了天线多频段共口径接收和波束窄、信号难捕获跟踪的技术难题。提出并采用“频率选... 详细信息

针对多频段遥感信号接收系统对S/C/X/Ku/Ka五频段信号共口径接收、高精度指向和全空域过顶稳定跟踪需求,研制了一种多频段遥感信号接收天伺馈系统,解决了天线多频段共口径接收和波束窄、信号难捕获跟踪的技术难题。提出并采用“频率选择副面+旋转”换馈方式、高精度筋开槽微应力胶粘面板、时间最优的非线性多模自适应跟踪控制技术,实现了多频段信号高可靠共口径接收和高精度指向及稳定过顶跟踪。对塔测试结果表明,所设计的多频段共口径接收天伺馈系统具有优良的性能,天线增益、第一旁瓣电平、差波束零深、跟踪精度和指向精度等各项指标均满足指标要求;对星动态跟踪测试表明,Ka频段指向均方根误差优于0.0136°,Ka频段跟踪方位均方根误差优于0.0056°,俯仰均方根误差优于0.0045°。验证了所提天伺馈系统设计的有效性,可用于指导多频段大口径遥感接收天伺馈系统设计。

关键词：多频段天线频率选择副面旋转换馈伺服系统过顶跟踪

Biological conduits combining bone marrow mesenchymal stem cells and extracellular matrix to treat long-segment sciatic nerve defects

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Neural Regeneration Research 2015年第6期10卷 965-971页

作者： Yang Wang Zheng-wei Li Min Luo Ya-jun Li ke-qiang Zhang Department of Orthopedics China-Japan Friendship HospitalJilin University Department of Orthopedics Second HospitalJilin University Mathematics School Jilin University

The transplantation of polylactic glycolic acid conduits combining bone marrow mesenchymal stem cells and extracellular matrix gel for the repair of sciatic nerve injury is effective in some respects, but few data comparing the biomechanical factors related to the sciatic nerve are available. In the present study, rabbit models of 10-mm sciatic nerve defects were prepared. The rabbit models were repaired with autologous nerve, a polylactic glycolic acid conduit ＋ bone marrow mesenchymal stem cells, or a polylactic glycolic acid conduit ＋ bone marrow mesenchymal stem cells ＋ extracellular matrix gel. After 24 weeks, mechanical testing was performed to determine the stress relaxation and creep parameters. Following sciatic nerve injury, the magnitudes of the stress decrease and strain increase at 7,200 seconds were largest in the polylactic glycolic acid conduit ＋ bone marrow mesenchymal stem cells ＋ extracellular matrix gel group, followed by the polylactic glycolic acid conduit ＋ bone marrow mesenchymal stem cells group, and then the autologous nerve group. Hematoxylin-eosin staining demonstrated that compared with the polylactic glycolic acid conduit ＋ bone marrow mesenchymal stem cells group and the autologous nerve group, a more complete sciatic nerve regeneration was found, including good myelination, regularly arranged nerve fibers, and a completely degraded and resorbed conduit, in the polylactic glycolic acid conduit ＋ bone marrow mesenchymal stem cells ＋ extracellular matrix gel group. These results indicate that bridging 10-mm conduit ＋ bone marrow mesenchymal stem sciatic nerve defects with a polylactic glycolic acid cells ＋ extracellular matrix gel construct increases the stress relaxation under a constant strain, reducing anastomotic tension. Large elongations under a constant physiological load can limit the anastomotic opening and shift, which is beneficial for the regeneration and functional reconstruction of sciatic nerve. Better regeneration was fou

关键词： nerve regeneration peripheral nerve injury rabbits sciatic nerve injury autologous nerye repair polylactic glycolic acid conduit extracellular matrix gel grafting stress relaxation creep viscoelasticity histomorphology electrophysiology neural regeneration

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脂肪醇的味阈值与分子结构之间的定量关系

有机化学 2000年第3期20卷 382-387页

作者：王克强李勤洛阳师范高等专科学校化学系洛阳471022 河南省医药学校开封475001

通过拓扑方法探讨了脂肪醇的味阈值与分子结构之间的关系,发现脂肪醇的味阈值主要取决于分子的大小和羟基在分子中的位置(且羟基的位置对味阈值的影响十分显著),提出一个既能表征脂肪醇结构与味阈值之间关系、又能预测味阈值的定量关系... 详细信息

通过拓扑方法探讨了脂肪醇的味阈值与分子结构之间的关系,发现脂肪醇的味阈值主要取决于分子的大小和羟基在分子中的位置(且羟基的位置对味阈值的影响十分显著),提出一个既能表征脂肪醇结构与味阈值之间关系、又能预测味阈值的定量关系式,发展了一种设计具有特定味阈值的脂肪醇分子结构的方法。对99种脂肪醇的计算结果表明,味阈值预测值与计算值与实验值的一致性令人满意。

关键词：味阈值脂肪醇分子结构性能定量关系

家蚕蛹表达的重组Vp28疫苗对克氏原螯虾免疫反应的影响

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分子细胞生物学报 2006年第6期39卷 527-536页

作者：魏克强山西大学生命科学与技术学院

将含有对虾白斑综合征病毒囊膜蛋白Vp28基因的重组杆状病毒HyNPV-Vp28感染家蚕(Bombyx mori)蛹,配制成药饵持续口服免疫克氏原螯虾35天后,螯虾血细胞的吞噬百分比和吞噬指数比对照组显著提高(P＜0．05)；血清中的抗菌活力、溶菌活力、... 详细信息

将含有对虾白斑综合征病毒囊膜蛋白Vp28基因的重组杆状病毒HyNPV-Vp28感染家蚕(Bombyx mori)蛹,配制成药饵持续口服免疫克氏原螯虾35天后,螯虾血细胞的吞噬百分比和吞噬指数比对照组显著提高(P＜0．05)；血清中的抗菌活力、溶菌活力、酚氧化酶活性、超氧化物歧化酶活性以及血清和肝胰腺组织中的酸性磷酸酶、碱性磷酸酶活性均显著提高(P＜0．05)。免疫35天后进行口服攻毒,20天内rVp28疫苗组的累积存活率达66．67%,与对照组和对照蚕蛹组比差异显著(P＜0．05),PRP分别达64．29%和58．33%。rVp28疫苗组存活虾的胃、肠、鳃、甲壳下上皮和肝胰腺等病毒侵染的靶组织进行组织病理检测均无病毒感染,DIG标记核酸探针斑点杂交和PCR检测也呈阴性反应；而试验濒死虾的组织都呈现典型的病变特征,病毒DNA检测均为阳性反应。本研究表明,口服免疫家蚕蛹表达的囊膜蛋白Vp28具有增强螯虾机体免疫功能的作用,对应用免疫措施预防对虾的病毒性疾病具有重要意义。

关键词：白斑综合征病毒囊膜蛋白Vp28 克氏原螯虾免疫反应

Construction of a nomogram model to predict technical difficulty in performing laparoscopic sphincter-preserving radical resection for rectal cancer

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World Journal of Gastroenterology 2024年第18期30卷 2418-2439页

作者： Xiao-Cong Zhou Shi-Wei Guan Fei-Yue ke Gaurav Dhamija qiang Wang Bang-Fei Chen Medical University(Wenzhou Central Hospital) Wenzhou 325000Zhejiang ProvinceChina Department of Hepatobiliary Surgery The Dingli Clinical Institute of Wenzhou Medical University(Wenzhou Central Hospital)Wenzhou 325000Zhejiang ProvinceChina Postgraduate Training Base Alliance of Wenzhou Medical University Wenzhou Central HospitalWenzhou 325000Zhejiang ProvinceChina School of International Studies Wenzhou Medical UniversityWenzhou Central HospitalWenzhou 325000Zhejiang ProvinceChina Department of Radiology The Dingli Clinical Institute of Wenzhou Medical University(Wenzhou Central Hospital)Wenzhou 325000Zhejiang ProvinceChina Department of Colorectal Surgery The Affiliated Zhejiang HospitalZhejiang University School of Medicine(Zhejiang Hospital)Hangzhou 310000Zhejiang ProvinceChina

BACKGROUND Colorectal surgeons are well aware that performing surgery for rectal cancer becomes more challenging in obese patients with narrow and deep pelvic ***,it is essential for colorectal surgeons to have a comprehensive understanding of pelvic structure prior to surgery and anticipate potential surgical *** To evaluate predictive parameters for technical challenges encountered during laparoscopic radical sphincter-preserving surgery for rectal *** We retrospectively gathered data from 162 consecutive patients who underwent laparoscopic radical sphincterpreserving surgery for rectal ***-dimensional reconstruction of pelvic bone and soft tissue parameters was conducted using computed tomography(CT)*** difficulty was categorized as either high or low,and multivariate logistic regression analysis was employed to identify predictors of operative difficulty,ultimately creating a *** Out of 162 patients,21(13.0%)were classified in the high surgical difficulty group,while 141(87.0%)were in the low surgical difficulty *** logistic regression analysis showed that the surgical approach using laparoscopic intersphincteric dissection,intraoperative preventive ostomy,and the sacrococcygeal distance were independent risk factors for highly difficult laparoscopic radical sphincter-sparing surgery for rectal cancer(P<0.05).Conversely,the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance was identified as a protective factor(P<0.05).A nomogram was subsequently constructed,demonstrating good predictive accuracy(C-index=0.834).CONCLUSION The surgical approach,intraoperative preventive ostomy,the sacrococcygeal distance,and the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance could help to predict the difficulty of laparoscopic radical sphincter-preserving surgery.

关键词： Nomogram Rectal cancer Laparoscopic operation Sphincter-preserving surgery Technical difficulty

Detection and Quantification of Water-Soluble Inorganic Chlorine,Bromine and Iodine by MALDI-MS

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Journal of Analysis and Testing 2022年第4期6卷 419-423页

作者： Yi Tong Zheng-Zheng Liu Jia-Feng Lu Hai-Yan Zhang ke-qiang Shi Guan-Ru Chen Ya-Qin Liu Hong-Ru Feng Yuan-Jiang Pan Department of Chemistry Zhejiang UniversityHangzhou310027China Zhejiang key Laboratory of Ecological and Environmental Monitoring Forewarning and Quality ControlZhejiang Ecological and Environmental Monitoring CenterHangzhou310012China School of Environment Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou310000China

Halogens are elements in soil and water that occur as organic and inorganic *** have shown that inorganic halogens are closely related to animal and plant ***-assisted laser desorption/ionization mass spectrometry(MALDI-MS)can achieve high-throughput and rapid analysis,which is also an essential characteristic in some environmental ***,there is currently no report on MALDI-MS analysis for water-soluble inorganic halogen *** this study,we aimed to develop a reliable and reproductive method to detect inorganic halogens in soil and water by *** on sinapic acid(SA)and silver trifluoromethanesulfonate(SA/AgOTf)as the matrix in negative-ion mode,MALDI-MS showed excellent MS signals related to *** the optimum conditions,the method achieved satisfactory linearity(R^(2)>0.99)and repeatability(RSD<18%).The LODs for Cl^(−),Br^(−)and I^(−)were 0.76,0.11 and 0.10μg/mL,*** concentration of inorganic halogens from 24 samples was successfully determined by *** summary,an innovative method was developed for the analysis of inorganic halogens by MALDI-MS using a novel SA/AgOTf matrix,extending the application of MALDI-MS in inorganic compounds.

关键词： MALDI-MS Water-soluble halogen Quantification Soil Water