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Adaptive backstepping control of tracked robot running trajectory based on real-time slip parameter estimation

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International Journal of Agricultural and Biological Engineering 2020年第4期13卷 178-187页

作者： En Lu zheng Ma Yaoming li lizhang Xu Zhong Tang School of Agricultural Equipment Engineering Jiangsu UniversityZhenjiangJiangsu 212013China World Precise Machinery(China)Co. LtdWorld Industrial ParkPicheng TownDanyangJiangsu 212311China

To ensure the stable driving of tracked robots in a complex farmland environment,an adaptive backstepping control method for tracked robots was proposed based on real-time slip parameter *** to the kinematics analysis method,the kinematic model of the tracked robot was established,and then,its pose error differential equation was further *** this basis,the trajectory tracking controller of the tracked robot was designed based on the backstepping control ***,according to the trajectory tracking error of the tracked robot,the back propagation neural network(BPNN)was used to adaptively adjust the control parameters in the backstepping controller,and the inputs of the BPNN are the trajectory tracking error xe,ye,θ*** that,the soft-switching sliding mode observer(SSMO)was designed to identify the slip parameters during the running of the tracked *** then the parameters were compensated into the adaptive backstepping controller to reduce the trajectory tracking *** simulation results show that the proposed adaptive backstepping control method with SSMO can improve the accuracy of the trajectory tracking control of the tracked ***,the designed SSMO can accurately estimate the slip parameters.

关键词： tracked robot trajectory control adaptive backstepping control neural networks slip parameter sliding mode observer

Factors influencing improvement of visual field after trans-sphenoidal resection of pituitary macroadenomas:a retrospective cohort study

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International Journal of Ophthalmology(English edition) 2015年第6期8卷 1224-1228页

作者： Fen-Fen Yu li-li Chen Yi-Hua Su li-Hun Huo Xian-Xuan lin rui-Duan liao Department of Ophthalmology the First Affiliated HospitalSun Yat-sen University Department of Pathology the First Affiliated Hospital Sun Yat-sen University

AIM: To investigate the influencing factors of visual field improvement after trans-sphenoidal resection of pituitary macroadenomas. METHODS: This retrospective cohort study included 201 patients (366 eyes) with visual field defect induced by pituitary macroadenomas. All of them were treated with trans-sphenoidal surgery. Ophthalmologic evaluation, best -corrected visual acuity (BCVA), and visual field examination were performed before and 3mo after surgery. BCVA, visual field defect index mean deviation (MD), duration of symptoms, age, sex, and volume of tumors were compared. Expression of vascular endothelial growth factor (VEGF) and Ki-67 of tumor tissue were detected by immunohistochemical technique. RESULTS: The mean age of patients was 44.23 +/- 1.29y. Ninety -three patients were female and 108 were male. The mean tumor volume was 14.36 +/- 6.23 cm(3). The mean duration of preoperative symptoms was 11.50 +/- 0.88mo. Mean preoperative MD was -17.50 +/- 0.82 dB. Mean Preoperative visual acuity was 0.64 +/- 0.04. Postoperative visual field improved in 270 (73.77%) eyes, unchanged in 96 (26.23%) eyes. Multivariate logistic regression displayed that the factors independently influencing visual field improvement were young age (OR=1.71, 95%CI: 1.325-2.387, P=0.013), low preoperative MD absolute value (OR=1.277, 95%CI: 1.205-1.355, P<0.001), small volume of tumor (OR=1.458, 95%CI: 1.060-4.289, P<0.001), low expression of VEGF in tumor tissue (OR=1.554, 95%CI: 1.089-2.457, P=0.022), and low expression of Ki-67 in tumor tissue (OR=1.552, 95%CI: 1.161-2.847, P=0.026). CONCLUSION: After pituitary macroadenomas trans sphenoidal resection, the independent influencing factors of the visual fields recovery were low preoperative MD absolute value, young age, small volume of tumor, and expression levels of VEGF/Ki-67.

关键词： pituitary adenoma visual field influencing factors vascular endothelial growth factor Ki-67

Power control for two-way amplify-and-forward relaying over Rayleigh fading channels

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第4期12卷 280-287页

作者： Xing-zheng li Yuan-an liU Gang XIE Pan-liang DENG Fang liU School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

We propose two novel power control policies for a two-way amplify-and-forward (AF) relaying system,in which each node (two sources and one relay) is assumed to operate under bothminimum and peak power *** the exploitation of instantaneous channel gains,the first policy can maximize the sum rate of the ***,the instantaneous channel gains may be unavailable in a rapid time-varying system,where the first policy is ***,a robust power control policy which requires only mean channel gains is proposed to maximize the upper bound of the average sum rate,and the properties of this policy are *** results show that,by comparison with the policy in which all the nodes use their peak transmit power,the proposed power control policies can provide considerable system performance ***,the performance difference between the two proposed policies is negligible when the relay is close to one source.

关键词： Amplify-and-forward (AF) relaying Power control Two-way relay channel Bidirectional relaying Cooperative communication

Comparative analysis of NovaSeq 6000 and MGISEQ 2000 single-cell RNA sequencing data

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Quantitative Biology 2022年第4期10卷 333-340页

作者： Weiran Chen Md Wahiduzzaman Quan li Yixue li Guangyong zheng Tao Huang Bio-Med Big Data Center Key Laboratory of Computational BiologyShanghai Institute of Nutrition and HealthChinese Academy of SciencesShanghai 200031China School of life Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

Background:Single-cell RNA sequencing(scRNA-seq)technology is now becoming a widely applied method of transcriptome exploration that helps to reveal cell-type composition as well as cell-state heterogeneity for specific biological *** sequencing platforms and processing pipelines may contribute to various results even for the same sequencing ***,benchmarking sequencing platforms and processing pipelines was considered as a necessary step to interpret scRNA-seq ***,recent comparing efforts were constrained in sequencing platforms or analyzing *** is still a lack of knowledge of analyzing pipelines matched with specific sequencing platforms in aspects of sensitivity,precision,and so ***:We downloaded public scRNA-seq data that was generated by two distinct sequencers,NovaSeq 6000 and MGISEQ *** data was processed through the Drop-seq-tools,UMI-tools and Cell Ranger pipeline *** calculated multiple measurements based on the expression profiles of the six platform-pipeline ***:We found that all three pipelines had comparable performance,the Cell Ranger pipeline achieved the best performance in precision while UMI-tools prevailed in terms of sensitivity and marker ***:Our work provided an insight into the selection of scRNA-seq data processing tools for two sequencing platforms as well as a framework to evaluate platform-pipeline combinations.

关键词： Single-cell RNA sequencing cell-type data processing pipeline platform

Transient liquid-phase to guide multiphase evolution in reactive-hotpressed ZrB_(2)-SiC-ZrC ceramics

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Journal of Materiomics 2020年第3期6卷 607-617页

作者： Qiang zheng Hui Gu Dong-li Hu Guo-Jun Zhang CAS Key Laboratory of Standardization and Measurement for Nanotechnology CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing100190China School of Materials Science and Engineering Materials Genome InstituteShanghai UniversityShanghai200444China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Research Institute of Functional MaterialsDonghua UniversityShanghai201620China State Key Laboratory of High Performance Ceramics and Superfine Microstructures Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China

In reactive-hot-pressed ZrB_(2)-SiC-ZrC ceramics,ZrO_(2) was found to replace ZrC phase,hence leading to confusion in designing ultra-high-temperature ceramics(UHTCs).We employ high-precision X-ray diffraction and electron microscopies to reassess the phase behavior during entire reaction and densification and to reveal the evolution of multiphase relationship at different stages before reaching the final ZrB2-SiC-ZrO_(2) *** from transient liquid-phase,bulk glassy phase of 15 vol% was found to be constituted of Zr-Si-B-C-O with stable Zr:O ratio,which starts as early as in the intermediate stage to suppress ZrC in favor of SiC *** in phase relations and microstructures results from variation in local transient liquid-phase to develop SiC phase in various modes and *** inferred from the earlier report of phase formation,competing reactions for ZrC and ZrB_(2) phases in the initial stage below 1000℃ were mediated via Zr-O-B-C liquid *** liquid phase was moderated by stable B-O components,as initiated from surface oxides of starting *** picture under a continuous mother liquid phase can unify the reactions and sintering into a collective meltingenucleationegrowth process,which enables and guides the evolution of multiphase relationship through several stages to reach final densification at relatively low temperature with the help of residual oxides.

关键词： Ultra-high-temperature ceramics Microstructure liquid-phase sintering Multiphase evolution

Prototypes,modifications,and hydrocarbon enrichment variations in basins influenced by Tethyan evolution:A comparative analysis of the Persian Gulf Basin and the Sichuan Basin

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Science China Earth Sciences 2023年第12期66卷 2871-2897页

作者： Zhiliang HE Zhijun JIN Shuangjian li Guoping BAI Xueyan LV Jinrui GUO Jian GAO Jinyin YIN Yingqiang li Dingye zheng China Petroleum&Chemical Corporation Beijing 100728China Institute of Energy Peking UniversityBejing 100871China SINOPEC Petroleum Exploration and Production Research Institute Beijing 102206China SINOPEC Key Laboratory of Geology and Resources in Deep Stratum Beijing 102206China

The hydrocarbon accumulation modes and differences in the Tethyan realm serve as a hot research topic in the petroleum geology community at home and *** the Persian Gulf Basin in the Middle East and the Sichuan Basin in China,situated on the southern and northern sides of the Tethyan realm,respectively,record the whole geological process of the opening and closure of the Prototethys,the Paleotethys,and the Neotethys sequentially,exhibiting anomalous hydrocarbon *** on the analysis of the plate tectonic evolution in the Tethyan realm,this study dissects the structures and hydrocarbon accumulation conditions of both *** by a systematic comparative analysis of the factors controlling hydrocarbon enrichment in the process of plate breakup and convergence in the Tethyan realm,this study proposes petroleum exploration targets in the *** results are as follows:(1)Since the Meso-Neoproterozoic,the Persian Gulf Basin and the Sichuan Basin have undergone similar tectonic evolution in the early stage but different in the late *** the influence of the formation and evolution of the Prototethys,Paleotethys,and Neotethys oceans,both basins experienced multi-stage development and modification,forming two major extension-convergence ***,both basins are characterized by the vertical orderly superimposition of various basin prototypes in the order of rift-intracratonic basin(passive continental margin)-foreland.(2)The fact that the Tethyan realm was long located at medium-low latitudes and the local anoxic environment formed in the process of plate breakup and convergence played a vital role in the formation of extensive source *** source rocks are predominantly distributed in underfilled rifts and deep depressions that were connected to the ocean in the unidirectional continental breakup process;basin-slopes and intra-shelf basins on passive continental margins;basinal lows within intracratonic basins,and underfill

关键词： Tethyan realm Unidirectional breakup and convergence Basin prototype Structural modification Hydrocarbon enrichment Exploration target Persian Gulf Basin Sichuan Basin

Artificial stepwise light harvesting system in water constructed by quadruple hydrogen bonding supramolecular polymeric nanoparticles

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Chinese Chemical Letters 2024年第2期35卷 370-373页

作者： Tangxin Xiao Xiuxiu li liangliang Zhang Kai Diao zheng-Yi li Xiao-Qiang Sun Leyong Wang Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology School of Petrochemical EngineeringChangzhou UniversityChangzhou 213164China Jiangsu Key Laboratory of Advanced Organic Materials School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Stepwise energy transfer is ubiquitous in natural photosynthesis,which greatly promotes the widespread use of solar ***,we constructed a supramolecular light harvesting system based on sequential energy transfer through the hierarchical self-assembly of M,which contains a cyanostilbene core flanked by two ureidopyrimidinone motifs,endowing itself with both aggregation-induced emission behavior and quadruple hydrogen bonding *** monomer M can self-assemble into hydrogen bonded polymers and then form supramolecular polymeric nanoparticles in water through a mini-emulsion *** nanoparticles were further utilized to encapsulate the relay acceptor ESY and the final acceptor NDI to form a two-step FRET *** fluorescence including a white-light emission was successfully *** work not only shows a desirable way for the fabrication of efficient two-step light harvesting systems,but also shows great potential in tunable photoluminescent nanomaterials.

关键词： light harvesting system Supramolecular polymer Quadruple hydrogen bonding AIE Self-assembly

Precipitation of α″-Fe_(16)N_2 Phase

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Journal of Materials Science & Technology 1998年第5期14卷 473-474页

作者： Haimei zheng Chunyang li Jian WANG and Baoyn li (Dept. of Material Science and Engineering, Tianjin University, Tianjin 300072, China) Dept. of Material Science and Engineering Tianjin University Tianjin 300072 China

Characteristics of the precipitate α″-Fe16N2 phase have been investigated by X-ray diffraction and TEM analysis. VSM measurements give the saturation magnetization of the α″ phase.

关键词： Fe Precipitation of N2 Phase

Scheme for Implementing Refined Deutsch-Jozsa Algorithm via Superconducing Qubits

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Communications in Theoretical Physics 2008年第4期49卷 909-912页

作者： zheng Xiao-Hu YU Ben-li ZHANG Gang CAO Zhuo-liang Key Laboratory of Opto-electronic Information Acquisition and Manipulation Ministry of Education School of Physics and Material Science Anhui University Hefei 230039 China Department of Mathematics and Physics West Anhui University Lu＇an 237012 China

We propose a scheme of implementing the Deutsch-Jozsa algorithm based on superconducing charge qubits, which would be a key step to scale more complex quantum algorithms and very important for constructing a real quantum computer via superconducting charge qubits. The present scheme is simple but fairly efficient, and easily manipulated because arbitrary two-qubit can be selectively and effectively coupled by a common inductance. More manipulations can be carried out before decoherence sets in. The proposed scheme is in line with current technology.

关键词： Deutsch-Jozsa algorithm superconduction superconducting charge qubits