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Sequential Inverse Optimal Control of Discrete-Time Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 608-621页

作者： sheng Cao Zhiwei Luo Changqin quan the Graduate School of System Informatics Kobe University Kobe 657-8501Japan

This paper presents a novel sequential inverse optimal control(SIOC)method for discrete-time systems,which calculates the unknown weight vectors of the cost function in real time using the input and output of an optimally controlled discrete-time *** proposed method overcomes the limitations of previous approaches by eliminating the need for the invertible Jacobian *** calculates the possible-solution spaces and their intersections sequentially until the dimension of the intersection space decreases to *** remaining one-dimensional vector of the possible-solution space’s intersection represents the SIOC *** paper presents clear conditions for convergence and addresses the issue of noisy data by clarifying the conditions for the singular values of the matrices that relate to the possible-solution *** effectiveness of the proposed method is demonstrated through simulation results.

关键词： Inverse optimal control promised calculation step sequential calculation

Revealing the Structure-Property Difference of Natural Rubber Prepared by Different Methods: Protein and Gel Content are Key Factors

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Chinese Journal of Polymer Science 2024年第4期42卷 457-467页

作者： Shao-Qi Huang Jun-Qi Zhang Yong Zhu Ling-Min Kong Lu-sheng Liao fu-quan Zhang Zheng-Tian Xie Jin-Rong Wu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China Hainan Provincial Key Laboratory of Natural Rubber Processing Agricultural Products Processing Research Institute of Chinese Academy of Tropical Agricultural SciencesZhanjiang524001China

Natural rubber (NR) is widely used in various fields including aerospace, military industry and transportation due to its superior elasticity and comprehensive mechanical properties. Nonetheless, the commercial NR prepared by different methods usually exhibits different mechanical properties, primarily due to variations in processing conditions during the conversion from latex to bulk rubber material. Consequently, this poses challenges in scientific research and industrial production of NR. In order to assess the properties of various commercially available NR and identify key structural and compositional components, this study systematically compares and analyzes four representative NR raw materials: air dried sheet (ADS), ribbed smoked sheets (RSS), constant viscidity NR (CV), and whole field latex rubber (WF). The investigation focuses on evaluating their static mechanical behavior, SIC behavior, wear resistance, and fatigue resistance. The findings indicate that protein and gel content exhibit a crucial influence on the NR properties. These constituents contribute to the formation of a high-crosslinking density region, generating a heterogeneous network structure within the rubber. This structure amplifies strains during deformation, leading to earlier and stronger strain-induced crystallization (SIC). Among the four commercial NR brands, RSS demonstrates superior overall mechanical and dynamic properties owing to its high protein and gel content. This study serves as a valuable reference for comprehending the differences in properties among various commercial NR, thereby offering guidance for the actual processing and selection of NR.

关键词： Natural rubber Processingmethod Protein Gel content Property

Effect of Mo and cold forging deformation on strength and ductility of cobalt-based alloy L605

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Journal of Iron and Steel Research International 2024年第7期31卷 1811-1823页

作者： Zhong-lin Wang Zhi-hua Gong quan Li Han-sheng Bao School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014017Inner MongoliaChina Institute of Special Steels Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China

Mo element was added to cobalt-based alloy L605,and cold forging deformation was *** effects of the addition and cold forging deformation on the microstructure and mechanical properties of the alloy were studied by thermodynamic calculation,electron backscatter diffraction,transmission electron microscopy,and X-ray *** stacking fault energy(SFE)of the alloy decreased after the addition,and the formation of stacking faults and intersections were promoted to improve the strength and *** tensile strength of the alloy with Mo increased from 1190 to 1702 MPa after 24%cold deformation,producing significant work *** strengthening mechanism is strain-induced martensitic transformation(SIMT)and deformation *** alloy,combined with Mo and after 24%deformation,had both high strength and ductility in comparison with the original cobalt-based alloy *** is attributed to the lower SFE which caused the increase in stacking fault *** the tensile process,theε-hcp phase was easily generated at the stacking fault to reduce the stress concentration and increase the *** SIMT by adjusting the density of stacking faults can improve the mechanical properties of cobalt-based ***ε-hcp phase,the interaction between deformation twins and dislocations,and the interaction between e-hcp phases during cold forging deformation caused local stress concentration,lowering ductility and toughness.

关键词： Cobalt-based alloy-Stacking fault energy Strain-induced martensitic transformation Deformation twin Cold forging deformation

Energy modeling and optimization of building condenser water systems with all-variable speed pumps and tower fans:A case study

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Building Simulation 2024年第7期17卷 1085-1111页

作者： Yong Cao Chuang Wang sheng Wang Xiao fu Xinguo Ming School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Air-Conditioning Equipment and System Energy Conservation Zhuhai 519070China GREE Electric Appliances Inc.of ZhuhaiZhuhai 519070China School of Environment and Energy Engineering Beijing University of Civil Engineering and ArchitectureBeijing 100044China Beijing Advanced Innovation Centerfor future Urban Design Beijing University of Civil Engineering and ArchitectureBeijing 100044China

The emergence of building condenser water systems with all-variable speed pumps and tower fans allows for increased efficiency and flexibility of chiller plants in partial load operation but also increases the control complexity of condenser water *** study aims to develop an integrated modeling technique for evaluating and optimizing the energy performance of such a condenser water *** proposed system model is based on the semi-physical semi-empirical chiller,pump,and cooling tower models,with capabilities of fully considering the hydraulic and thermal interactions in the condenser water loop,being solved analytically and much faster than iterative solvers and supporting the explicit optimization of the pump and tower fan frequency.A mathematical approach,based on the system model and constrained optimization technique,is subsequently established to evaluate the energy performance of a typical dual setpoint-based variable speed strategy and find its energy-saving potential and most efficient operation by jointly optimizing pumps and tower *** all-variable speed chiller plant from Wuhan,China,is used for a case study to validate the system model’s accuracy and explore its *** results showed that the system model can accurately simulate the condenser water system’s performance under various operating *** optimizing the frequencies of pumps and tower fans,the total system energy consumption can be reduced by 12%–13%compared to the fixed dual setpoint-based strategy with range and approach setpoints of 4℃and 2℃.In contrast,the energy-saving potential of optimizing the cooling tower sequencing is insignificant.A simple joint speed control method for optimizing the pumps and tower fans emerged,i.e.,the optimal pump and fan frequency are linearly correlated(if both are non-extremes)and depend on the chiller part load ratio only,irrespective of the ambient wet-bulb temperature and chilled water supply *** was also foun

关键词： all-variable speed chiller plant model-based optimization hydraulic and thermal coupling analytical solution dual setpoint-based variable speed control optimal joint speed control

Structural Characterization of Chloroplast Genome in Alpinia japonica(Thunb.)Miq.,a Medicinal Plant of the Genus Alpinia

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Phyton-International Journal of Experimental Botany 2024年第8期93卷 1897-1911页

作者： Wentao sheng Xi Lei Xinjie Chen quan Kuang Department of Biological Technology Nanchang Normal UniversityNanchang330032China

The analysis of chloroplast gene characteristics in Alpinia japonica(Thunb.)*** of great significance for developing relevant genetic *** high-throughput sequencing and bioinformatic research were performed to analyze the chloroplast genome characteristics of *** total chloroplast genome length of *** was 161,906 bp,with a typical circular tetrameric *** 133 genes were annotated,comprising 87 protein-coding,38 tRNA,and 8 rRNA ***,22 genes contained two copies,and 18 genes owned *** sequence analysis showed that it contains 321 simple sequence repeats(SSRs)and 37 long segment *** with the chloroplast genomes of eight representative plants in the genus Alpinia,the gene structure,type,and quantity were relatively ***12 was the highest variation site in the entire chloroplast gene.A phylogenetic tree showed that the genus Alpinia was the most closely related to the genus ***,*** is the most closely related to Alpinia chinensis belonging to the genus ***,the chloroplast genome of a new species was reported in the genus Alpinia,and a basis was provided for the utilization of Alpinia plants as a medical resource.

关键词： The genus Alpinia Alpinia japonica(Thunb.)Miq. chloroplast genome phylogenetic tree

Ligation-assisted endoscopic submucosal resection following unroofing technique for small esophageal subepithelial lesions originating from the muscularis propria

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World Journal of Gastroenterology 2024年第32期30卷 3748-3754页

作者： quan Lu quan-Zhou Peng Jun Yao Li-sheng Wang De-Feng Li Department of Gastroenterology Shenzhen People’s HospitalShenzhen 518020Guangdong ProvinceChina Department of Pathology Shenzhen People’s HospitalShenzhen 518020Guangdong ProvinceChina Department of Gastroenterology Shenzhen People’s HospitalThe Second Clinical Medical CollegeJinan UniversityShenzhen 518020Guangdong ProvinceChina The First Affiliated Hospital Southern University of Science and TechnologyShenzhen 518020Guangdong ProvinceChina

BACKGROUND The majority of esophageal subepithelial lesions originating from the muscularis propria(SEL-MPs)are benign in nature,although a subset may exhibit malignant *** endoscopic resection techniques are time-consuming and lack efficacy for small *** To evaluate the efficacy and safety of ligation-assisted endoscopic submucosal resection(ESMR-L)following unroofing technique for small esophageal *** From January 2021 to September 2023,17 patients diagnosed with esophageal SEL-MPs underwent ESMR-L following unroofing technique at the endoscopy center of Shenzhen People’s *** of clinicopathological characteristics and clinical outcomes were collected and *** The mean age of the patients was 50.12±12.65 *** mean size of the tumors was 7.47±2.83 mm and all cases achieved en bloc resection *** average operation time was 12.2 minutes without any *** identified 2 Lesions(11.8%)as gastrointestinal stromal tumors at very low risk,12 Lesions(70.6%)as leiomyoma and 3 Lesions(17.6%)as smooth muscle *** recurrence was found during the mean follow-up duration of 14.18±9.62 *** ESMR-L following roofing technique is an effective and safe technique for management of esophageal SEL-MPs smaller than 20 mm,but it cannot ensure en bloc resection and may require further treatment.

关键词： Subepithelial lesions Muscularis propria Esophagus Ligation Endoscopic submucosal resection

CP violation of baryon decays with Nπrescatterings

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Chinese Physics C 2024年第10期48卷 1-10页

作者： Jian-Peng Wang fu-sheng Yu MOE Frontiers Science Center for Rare Isotopes and School of Nuclear Science and TechnologyLanzhou UniversityLanzhou 730000China

There is a long-standing puzzle that the CP violation(CPV)in the baryon systems has never been wellestablished in experiments,while the CPV of mesons have been observed by *** this paper,we propose thatthe CpV of baryon decays can be generated with the rescatterings of a nucleon and a pion into some final states,i.e Nπ→Nπor Nππ.Benelited by the fruitful data of Nπscatterings,we can model-independently analyse the strongphases of b-baryon decays using the partial wave amplitudes of Nπ*** the most difficult problemof non-perturbative dynamics,it makes a great advantage to predict the CpV of baryon decays with a relatively *** understanding of the decay *** study the processes of∧_(b)^(0)→(pπ^(+)π^(-))h^(-)and(pπ^(0))h^(-)with h=πor *** is found that the global CPV of the above processes in the invariant mass regions of Nπscatterings are at theorder of several *** importantly,the local CPV in some regions of the Dalitz plots can reach the order of 10%,or be even *** the predicted results and the experimental data samples,we strong suggest tomeasure the CPV of∧_(b)^(0)→(pπ^(+)π^(-))K^(-),which has a large possibility to achieve the first observation of CPV in thebaryon system.

关键词： CP violation baryon decays Nπscatterings

Distribution and geochemical significance of alkylbenzenes for crude oil with different depositional environments and thermal maturities

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Petroleum Science 2024年第2期21卷 777-790页

作者： Bing-Kun Meng Dao-fu Song Yuan Chen sheng-Bao Shi School of Petroleum Engineering and Environmental Engineering Yan'an UniversityYan'an716000ShaanxiChina State Key Laboratory of Petroleum Resources and Prospecting College of GeosciencesChina University of PetroleumBeijing102249China

A total of 45 alkylbenzenes were detected and identified in crude oils with different depositional environments and thermal maturities from the Tarim Basin,Beibuwan Basin,and Songliao Basin using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry(GC×GCTOFMS).By analyzing the distribution characteristics of C0-C5alkylbenzenes,it is found that the content of some alkylbenzenes varies greatly in crude *** on the distribution characteristics of 1,2,4,5-tetramethylbenzene(Te MB)and 1,2,3,4-Te MB,the ratio of 1,2,4,5-Te MB to 1,2,3,4-Te MB is proposed to indicate the organic matter origin and depositional environment of ancient *** samples originated mainly from lower hydrobiont,algae,bacteria and source rocks deposited under reducing/anoxic conditions have low 1,2,4,5-/1,2,3,4-Te MB values(less than 0.6),while oil samples originated mainly from terrestrial higher plants and source rocks deposited under oxic/sub-oxic conditions have higher 1,2,4,5-/1,2,3,4-Te MB values(greater than 1.0).The significant difference of 1,2,4,5-/1,2,3,4-Te MB values is controlled by 1,2,4,5-Te MB content.1,2,4,5-Te MB content in oils derived from source rocks deposited in oxidized sedimentary environment(greater than 1.0 mg/g whole oil)is higher than that in oils from source rocks deposited in reduced sedimentary environment(less than 1.0 mg/g whole oil).1,2,4,5-/1,2,3,4-Te MB ratio might not or slightly be affected by evaporative fractionation,biodegradation and thermal maturity.1,2,4,5-/1,2,3,4-Te MB ratio and 1,2,4,5-Te MB content can be used as supplementary parameter for the identification of sedimentary environment and organic matter *** should be noted that compared to the identification of organic matter sources,the 1,2,4,5-/1,2,3,4-Te MB parameter is more effective in identifying sedimentary environments.

关键词： 1 2 4 5-Tetramethylbenzene GC×GC-TOFMS Organic matter origin Depositional environment

Molecular docking-aided AIEgen design: concept, synthesis and applications

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Science China Chemistry 2024年第8期67卷 2614-2628页

作者： Jian-Qing Zhang Xiao-Yu Xu fu-sheng Liu Shu-Qiang Cao Yu-Xin Gui Yi-Wen Su Xiao-Yu He Ji-Yuan Liang You-quan Zou Department of Radiation and Medical Oncology Zhongnan Hospital of Wuhan UniversitySchool of Pharmaceutical SciencesWuhan UniversityWuhan 430071China Key Laboratory of Combinatorial Biosynthesis and Drug Discovery Ministry of EducationWuhan UniversityWuhan 430071China Tai Kang Center for Life and Medical Sciences Wuhan UniversityWuhan 430071China Department of Hepatobiliary Pancreatic SurgeryZhongnan Hospital of Wuhan UniversityWuhan 430071China

Aggregate-induced emission luminogens(AIEgens) have been widely used in biological imaging, chemical sensing, and disease treatments. The rational design and construction of AIEgens have received considerable research interests during the last few years. Herein, molecular docking-aided AIEgen design has been reasonably proposed and AIEgen TBQZY with excellent ~1O_(2) generation ability has been synthesized. The newly developed TBQZY could efficiently kill S. epidermidis and methicillinresistant S. epidermidis(MRSE) by tightly binding to bacteria and triggering the accumulation of ~1O_(2) in bacteria. TBQZY specifically regulated the immune system and polarized macrophages from M1 to M2 to accelerate the elimination of biofilm in vivo. In addition, healing acceleration was observed in chronic wounds treated with TBQZY, and side effects were ***, TBQZY had extraordinary potential for combating drug-resistant bacteria in the clinical setting. This research not only provided new concepts for the design of AIEgens, but also shed some lights on the discovery of drugs against drug-resistant bacteria.

关键词： AIEgen molecular docking drug-resistant bacteria biofilm chronic wounds healing