检索结果-南通市图书馆

Compensated acceleration feedback based active disturbance rejection control for launch vehicles

Chinese Journal of Aeronautics 2024年第4期37卷 464-478页

作者： Xiaoyan ZHANG Wenchao xue Zibo liu Ran ZHANG Huifeng LI Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Astronautics Beihang UniversityBeijing 100191China

In this paper, the attitude tracking and load relief control problems against wind disturbances and uncertain aerodynamics as well as the engine thrust of launch vehicles are ***, a framework of Compensated Acceleration Feedback based Active Disturbance Rejection Control(CAF-ADRC) is established to achieve both desired attitude tracking and load relief performances. In particular, the total disturbance that includes the effects caused by both aerocoefficient perturbations and disturbances is estimated by constructing an Extended State Observer(ESO) to achieve attitude tracking. Furthermore, combined with the normal acceleration due to the engine thrust, the accelerometer measurement is also compensated to enhance the load relief ***, the quantitative analysis of ESO and the entire closed-loop system are studied. It can be concluded that the desired attitude tracking and load relief performances can be achieved simultaneously under the proposed approach. Besides, tuning laws of the proposed approach are systematically given, which are divided into ESO, Proportional Derivative(PD) and Compensated Acceleration Feedback(CAF) modules. Moreover, the performances under CAF-ADRC approach can be better than those under CAF based PD(CAF-PD) approach by tuning load relief ***, the approach presented is applied to a typical control problem of launch vehicles with wind disturbances and parameter uncertainties.

关键词： Launch vehicles Uncertainty analysis Active disturbance rejection control(ADRC) Load relief control Extended state observer(ESO)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Evolution of molecular structure of TATB under shock loading from transient Raman spectroscopic technique

引用

Defence Technology（防务技术） 2024年第3期33卷 613-620页

作者： Hongliang Kang xue Yang Wenshuo Yuan Lei Yang Xinghan Li Fusheng liu Zhengtang liu Qijun liu Bond and Band Engineering Group School of Physical Science and TechnologySouthwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China

By combination of the transient Raman spectroscopic measurement and the density functional theoretical calculations,the structural evolution and stability of TATB under shock compression was *** to the improvement in synchronization control between two-stage light gas gun and the transient Raman spectra acquisition,as well as the sample preparation,the Raman peak of the N-O mode of TATB was firstly observed under shock pressure up to 13.6 GPa,noticeably higher than the upper limit of 8.5 GPa reported in available *** taking into account of the continuous shift of the main peak and other observed Raman peaks,we did not distinguish any structural transition or any new ***,both the present Raman spectra and the time-resolved radiation of TATB during shock loading showed that TATB exhibits higher chemical stability than previous *** reveal the detailed structural response and evolution of TATB under compression,the density functional theoretical calculations were conducted,and it was found that the pressure make N-O bond lengths shorter,nitro bond angles larger,and intermolecular and intra-molecular hydrogen bond interactions *** observed red shift of Raman peak was ascribed to the abnormal enhancement of H-bound effect on the scissor vibration mode of the nitro group.

关键词： TATB Raman spectra Structural evolution Shock loading

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

On electro-acoustic characteristics of a marine broadband sparker for seismic exploration

引用

Journal of Oceanology and Limnology 2024年第3期42卷 760-771页

作者： jing LI Kai liu Liancheng ZHANG Chenguang liu Yanliang PEI Baohua liu Key Laboratory of Marine Geology and Metallogency First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory of Marine Geology Laoshan LaboratoryQingdao 266237China Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou 310018China Key Laboratory of Submarine Acoustic Investigation and Application of Qingdao(Preparatory) Qingdao 266061China Key Laboratory of Deep Sea Mineral Resources Development Shandong(Preparatory)Qingdao 266061China

The construction of major marine infrastructure projects and the exploration and development of deep-sea mineral resources require fine imaging of seabed strata and *** highresolution marine seismic exploration based on a high broadband sparker source is an important approach to reveal seabed stratum and reservoir structure,and identify *** optimize the performance of sparker seismic source,we investigated the electro-acoustic characteristics of spark discharge under conditions of different charging voltages and electrode *** show that the sound source level increased with the increase of the charging voltage,whereas the main frequency decreased when the charging voltage *** addition,it was found that the charging capacitance had more obvious influence on the main frequency than the sound source level *** the load energy decreased with increasing electrode number,the sound source level still increased but the main frequency ***,the primary to bubble(P/B)ratio increased with the increase of the electrode *** gain a deeper insight into the electro-acoustic characteristics,we investigate the relationship between sound source level and power peak,from which a good correlation was observed.A more practical statistical analysis on the rise rate of current was processed,and a perfect logarithmic function was ***,we found that the main frequency was most possibly subjected to the electrical energy,especially the charging energy per *** results indicate that the charging energy per electrode less than 10 J could increase the main frequency to above 300 *** last,the main frequency could be reduced to 20 Hz when the charging energy of a single-electrode discharge was enhanced to over 4 *** study shall be helpful in developing a sparker seismic source and improving the performance for marine engineering exploration and geohazard assessment.

关键词： high-resolution marine seismic exploration sparker seismic source sound source level main frequency electro-acoustic characteristics

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Flavor mixing and solution structures in Dyson–Schwinger equations for a two-flavor system

引用

Communications in Theoretical Physics 2024年第10期76卷 64-77页

作者： xue-ao Chao Yu-xin liu Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Collaborative Innovation Center of Quantum Matter Center for High Energy Physics Peking University

We solved the Dyson–Schwinger(DS) equations for a two-flavor system with symmetry to study its flavor mixing effects. Initially, we employed the point interaction model and bare vertex approximation to reveal the structure of the solutions. Using the point interaction model, the DS equations can be solved analytically, and we found that these solutions can be classified into three groups, each forming an ellipse. These solutions exhibit SO(2) symmetry, while the original SU(2)symmetry at the Lagrangian level is dynamically broken to SO(2), corresponding to the emergence of flavor mixing effects. However, this flavor mixing effect does not manifest in the final physical *** utilizing the system's SO(2) symmetry, we can diagonalize the propagators of the DS equations,eliminating the flavor mixing effect but causing the originally degenerate masses at the Lagrangian level to split. These mass eigenstates have identical quantum numbers but different masses. If we can correspond these to quark particles of different generations, we can explain why the three generations of quarks have different masses and obtain the corresponding quark mass spectrum. Finally, we provide the corresponding numerical results using a more realistic interaction model.

关键词： dynamic symmetry breaking Dyson-Schwinger equation flavor change mass splitting

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Core-rim structured MXene@SiO_(2)composites as oil-based additives for enhanced tribological properties

引用

Friction 2024年第8期12卷 1728-1740页

作者： Yuhong CUI Shenghua xue Tiantian WANG Shujuan liu Qian YE Feng ZHOU Weimin liu State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Herein,we have prepared SiO_(2)particles uploaded MXene nanosheets via in-situ hydrolysis of *** to the large number of groups at the edges of MXene,SiO_(2)grows at the edges first,forming MXene@SiO_(2)composites with a unique core-rim *** tribological properties of MXene@SiO_(2)as lubricating additive in 500 SN are evaluated by *** results show that MXene@SiO_(2)can reduce the friction coefficient of 500 SN from 0.572 to 0.108,the wear volume is reduced by 73.7%,and the load capacity is increased to 800 *** superior lubricity of MXene@SiO_(2)is attributed to the synergistic effect of MXene and SiO_(2).The rolling friction caused by SiO_(2)not only improves the bearing capacity but also increases the interlayer distance of MXene,avoiding accumulation and making it more prone to interlayer ***@SiO_(2)is adsorbed on the friction interface to form a physical adsorption film and isolate the friction *** addition,the high temperature and high load induce the tribochemical reaction and form a chemical protection film during in the friction ***,the presence of these protective films results in MXene@SiO_(2)having good lubricating properties.

关键词： Ti3C2Tx MXene SiO_(2)nanoparticles lubricating additives protective film

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Analysis of destructive effect of Zn on carbon brick and way of Zn into carbon brick

引用

Journal of Iron and Steel Research International 2024年第6期31卷 1344-1354页

作者： Peng-bo liu Shu-sen Cheng Yu-qing xue Xiao-man Cheng Zhao liu University of Science and Technology Beijing Beijing 100083China Ministry of Ironmaking Shangdong Taishan Steel Group Co.Ltd.Taian 271000ShandongChina

The service life of a blast furnace depends largely on the degree of damage to the carbon brick in the *** brick and ramming material in the hearth of a 1780 m3 blast furnace after shutdown were sampled and *** was found that the substances in the cracks of the carbon brick near and above the taphole were ZnO and Zn_(2)SiO_(4),whereas the substances in the cracks of the carbon brick below the taphole were *** reaction of Zn with CO,SiO_(2),and Fes generates ZnO,Zn_(2)SiO_(4),and ZnS,resulting in volume expansion,which is an important reason for the cracking of carbon ***,several obvious Zn vapor flow channels were found in the ramming material,through which Zn vapor could enter the carbon brick,causing damage to the carbon *** the compactness of the ramming material is beneficial to preventing Zn vapor from entering the carbon brick through the voids in the ramming material,reducing the destructive effect of Zn on the carbon brick and further extending the service life of the blast furnace.

关键词： Zn Blast furnace Carbon brick Ramming material Crack

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A hybrid spatial-temporal deep learning prediction model of industrial methanol-to-olefins process

引用

Frontiers of Chemical Science and Engineering 2024年第4期18卷 73-85页

作者： Jibin Zhou xue Li Duiping liu Feng Wang Tao Zhang Mao Ye Zhongmin liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Yulin Innovation Institute for Clean Energy Clean Energy Innovation Institute of Chinese Academy of SciencesYulin 719053China xuelang Industrial Intelligence Technology Co. Ltd.Wuxi 214000China

Methanol-to-olefins,as a promising non-oil pathway for the synthesis of light olefins,has been successfully *** accurate prediction of process variables can yield significant benefits for advanced process control and *** challenge of this task is underscored by the failure of traditional methods in capturing the complex characteristics of industrial processes,such as high nonlinearities,dynamics,and data distribution shift caused by diverse operating *** this paper,we propose a novel hybrid spatial-temporal deep learning prediction model to address these ***,a unique data normalization technique called reversible instance normalization is employed to solve the problem of different data ***,convolutional neural network integrated with the self-attention mechanism are utilized to extract the temporal ***,a multi-graph convolutional network is leveraged to model the spatial ***,the extracted temporal and spatial features are fused as input into a fully connected neural network to complete the ***,the outputs are denormalized to obtain the ultimate *** monitoring results of the dynamic trends of process variables in an actual industrial methanol-to-olefins process demonstrate that our model not only achieves superior prediction performance but also can reveal complex spatial-temporal relationships using the learned attention matrices and adjacency matrices,making the model more ***,this model is deployed onto an end-to-end Industrial Internet Platform,which achieves effective practical results.

关键词： methanol-to-olefins process variables prediction spatial-temporal self-attention mechanism graph convolutional network

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Enhanced Grain Refining Effect of Mg–Zr Master Alloy on Magnesium Alloys via a Synergistic Strategy Involving Heterogeneous Nucleation and Solute‑Driven Growth Restriction

引用

Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1354-1366页

作者： Gang Zeng Hong liu jing‑Peng Xiong Jian‑Long Li Yong liu Key Laboratory of Lightweight and High Strength Structural Materials of Jiangxi Province School of Advanced ManufacturingNanchang UniversityNanchang 330031China

Zirconium(Zr)emerges as the most effective grain refiner for magnesium(Mg)alloys incorporating ***,Zr is introduced in the form of an Mg–Zr master ***,within Mg–Zr master alloys,Zr predominantly exists in a particle form,which tends to aggregate due to attractive van der Waals *** clustered Zr is prone to settling,thereby reducing its refining impact on Mg *** this work,a combined pretreatment process for Mg–Zr master alloys was proposed,encompassing the introduction of a physical field to intervene the agglomeration of particle Zr and the employ of high-temperature dissolution and peritectic reactions to promote the solid solution of *** results demonstrate that the particle Zr within the pretreated Mg–Zr master alloy is effectively dispersed and refined,and greater solute Zr levels can be *** subsequent grain refinement ability was studied on a typical Mg–6Zn–0.6Zr(wt%)*** outcome highlights that an improvement in the grain refinement efficacy(32.4%)of Mg–Zr master alloys was obtained with a holding time of 60 *** pretreated Mg–Zr master alloy significantly augments the efficiency of grain refinement for Mg alloys through a synergistic strategy involving heterogeneous nucleation and solute-driven growth *** crucial factor in achieving effective grain refinement of Zr in Mg alloys lies in regulating the presence and morphology of Zr in the Mg–Zr master alloy,distinguishing between particle Zr and solute *** study introduces a novel method for developing more efficient Mg–Zr refiners.

关键词： Magnesium alloy Mg-Zr master alloy Grain refinement Heterogeneous nucleation Solute-driven growth restriction Synergistic strategy

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CD3ε of a pan T cell marker involved in mouse Aspergillus fumigatus keratitis

引用

International Journal of Ophthalmology(English edition) 2024年第4期17卷 616-624页

作者： Wen-Hao Shi Li-Mei Wang Hai-jing Yan Shi-Long liu Xian Yang xue-JiaoYang Cheng-Ye Che Department of Ophthalmology the Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina Weifang Medical University Weifang 261053Shandong ProvinceChina Eye Hospital of Wenzhou Medical University Wenzhou 325027Zhejiang ProvinceChina Department of Medical Engineering the Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina

AIM:To explore whether CD3ε is involved in the adaptive immunity of Aspergillus fumigatus(***)keratitis in mice and the role of innate and adaptive immunity in ***:Mice models of *** keratitis were established by intra-stromal injection and corneal epithelial *** injections of natamycin,wedelolactone,LOX-1 inhibitor(poly I)or Dectin-1 inhibitor(laminarin)were used to treat mice with *** *** were pretreated by intraperitoneal injection of anti-mouse CD3ε.We observed the corneal infection of mice under the slit lamp microscope and made a clinical *** protein expression of CD3ε and interleukin-10(IL-10)was determined by Western ***:With the disease progresses,the degree of corneal opacity and edema *** the intrastromal injection models,CD3εprotein expression began to increase significantly on the 2^(nd) ***,in the scraping epithelial method models,CD3ε only began to increase on the 3^(rd) *** natamycin treatment,the degree of corneal inflammation in mice was significantly attenuated on the 3^(rd) *** wedelolactone treatment,the severity of keratitis *** the amount of CD3ε protein was also reduced,compared with the control *** inhibiting LOX-1 and Dectin-1,there was no significant difference in CD3ε production compared with the control *** inhibiting CD3ε,corneal ulcer area and clinical score increased,and IL-10 expression was ***:As a pan T cell marker,CD3ε participate in the adaptive immunity of *** keratitis in *** our mice models,the corneas will enter the adaptive immune stage *** regulating IL-10,CD3ε exerts antiinflammatory and repairs effects in the adaptive immune stage.

关键词： CD3ε adaptive immunity Aspergillus fumigatus keratitis interleukin-10

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Stepping forward:T-cell redirecting bispecific antibodies in cancer therapy

引用

Acta Pharmaceutica Sinica B 2024年第6期14卷 2361-2377页

作者： Xiaojing Qin Wenjing Ning Han liu xue liu Wenxin Luo Ningshao Xia State Key Laboratory of Vaccines for Infectious Diseases Xiang An Biomedicine LaboratorySchool of Public HealthXiamen UniversityXiamen 361102China National Institute of Diagnostics and Vaccine Development in Infectious Diseases State Key Laboratory of Molecular Vaccinology and Molecular DiagnosticsNational Innovation Platform for IndustryeEducation Integration in Vaccine Researchthe Research Unit of Frontier Technology of Structural Vaccinology of Chinese Academy of Medical SciencesXiamen UniversityXiamen 361102China

T cell-redirecting bispecific antibodies are specifically designed to bind to tumor-associated antigens,thereby engaging with CD3 on the T cell *** linkage between tumor cells and T cells actively triggers T cell activation and initiates targeted killing of the identified tumor *** antibodies have emerged as one of the most promising avenues within tumor ***,despite success in treating hematological malignancies,significant advancements in solid tumors have yet to be *** this review,we aim to address the critical challenges associated with T cellredirecting bispecific antibodies and explore novel strategies to overcome these obstacles,with the ultimate goal of expanding the application of this therapy to include solid tumors.

关键词： Bispecific antibody(BsAbs) T-cell redirecting BsAbs Tumor-associated antigens Toxicity Cytokine release syndrome Tumor microenvironment Cancer immunotherapy Combination therapy strategies

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：