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Object Helps u-Net Based Change Detectors

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 548-550页

作者： lan yan Qiang li Kenli li College of Computer Science and Electronic Engineering Hunan UniversityChangsha 410082China State Key laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China

Dear Editor,This letter focuses on leveraging the object information in images to improve the performance of the u-Net based change *** detection is fundamental to many computer vision *** existing solutions based on ... 详细信息

关键词： Net computer networks

Machine learning optimization strategy of shaped charge liner structure based on jet penetration efficiency

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DEFENCE TECHNOlOGY 2024年第9期39卷 23-41页

作者： Zhao, Ziqi li, Tong Sheng, Donglin Chen, Jian yan, Amin Chen, yan Wang, Haiying Chen, Xiaowei Dai, lanhong Chinese Acad Sci Inst Mech State Key Lab Nonlinear Mech Beijing 100190 Peoples R China univ Chinese Acad Sci Sch Future Technol Beijing 100049 Peoples R China univ Chinese Acad Sci Sch Engn Sci Beijing 100049 Peoples R China Beijing Inst Technol State Key Lab Explos Sci & Technol Beijing 100081 Peoples R China

Shaped charge liner (SCl) has been extensively applied in oil recovery and defense industries. Achieving superior penetration capability through optimizing SCl structures presents a substantial challenge due to intricate rate-dependent processes involving detonation-driven liner collapse, high-speed jet stretching, and penetration. This study introduces an innovative optimization strategy for SCl structures that employs jet penetration efficiency as the primary objective function. The strategy combines experimentally validated finite element method with machine learning (FEM-Ml). We propose a novel jet penetration efficiency index derived from enhanced cutoff velocity and shape characteristics of the jet via machine learning. This index effectively evaluates the jet penetration performance. Furthermore, a multi-model fusion based on a machine learning optimization method, called XGBOOST-MFO, is put forward to optimize SCl structure over a large input space. The strategy's feasibility is demonstrated through the optimization of copper SCl implemented via the FEM-Ml strategy. Finally, this strategy is extended to optimize the structure of the recently emerging CrMnFeCoNi high-entropy alloy conical liners and hemispherical copper liners. Therefore, the strategy can provide helpful guidance for the engineering design of SCl. (c) 2024 China Ordnance Society. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. ltd. This is an open access article under the CC BY-NC-ND license.

关键词： Jet penetration efficiency Shaped charge liner FEM-Ml XGBOOST MFO High-entropy alloy lONG ROD PERFORMANCE COMPRESSIBIlITY EXTENSION SEARCH DESIGN MODEl

A Reliable Iteration Algorithm for One-Bit Compressive Sensing on the unit Sphere

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 801-822页

作者： yan-cheng lu Ning BI An-hua WAN School of Mathematics Sun Yat-sen UniversityGuangzhou 510275China

The one-bit compressed sensing problem is of fundamental importance in many areas,such as wireless communication,statistics,and so ***,the optimization of one-bit problem coustrained on the unit sphere lacks an algorithm with rigorous mathematical proof of convergence and *** this paper,an iteration algorithm is established based on difference-of-convex algorithm for the one-bit compressed sensing problem constrained on the unit sphere,with iterating formula■,where C is the convex cone generated by the one-bit measurements andη_(1)>η_(2)>1/*** new algorithm is proved to converge as long as the initial point is on the unit sphere and accords with the measurements,and the convergence to the global minimum point of the l_(1)norm is discussed.

关键词： one-bit compressed sensing difference of convex algorithm iteration algorithm ■1-minimization

Molecular packing tuning via chlorinated end group enables efficient binary organic solar cells over 18.5%

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Carbon Energy 2024年第3期6卷 196-203页

作者： Yafeng li Zhenyu Chen Xingzheng yan Ziyi Ge Zhejiang Business Technology Institute NingboZhejiangChina Zhejiang Engineering Research Center for Energy Optoelectronic Materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingboZhejiangChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina

Designing novel nonfullerene acceptors(NFAs)is of vital importance for the development of organic solar cells(OSC).Modification on the side chain and end group are two powerful tools to construct efficient ***,based on the high-performance l8BO,we selected 3-ethylheptyl to substitute the inner chain of 2-ethylhexyl,obtaining the backbone of *** we introduced different halogen atoms of fluorine and chlorine on 2-(3-oxo-2,3-dihydro-1Hinden-1-ylidene)malononitrile end group(EG)to construct efficient NFAs named BON3-F and BON3-Cl,*** donor D18 was chosen to combine with two novel NFAs to construct OSC ***,D18:BON3-Cl-based device shows a remarkable power conversion efficiency(PCE)of 18.57%,with a high open-circuit voltage(V_(OC))of 0.907 V and an excellent fill factor(FF)of 80.44%,which is one of the highest binary PCE of devices based on D18 as the ***,BON3-F-based device shows a relatively lower PCE of 17.79%with a decreased FF of 79.05%.The better photovoltaic performance is mainly attributed to the red-shifted absorption,higher electron and hole mobilities,reduced charge recombination,and enhanced molecular packing in the D18:BON3-Cl ***,we performed stability tests on two binary systems;the D18:BON3-Cl and D18:BON3-F devices maintain 88.1%and 85.5%of their initial efficiencies after 169 h of storage at 85°C in an N2-filled glove box,*** work demonstrates the importance of selecting halogen atoms on EG and provides an efficient binary system of D18:BON3-Cl for further improvement of PCE.

关键词： binary organic solar cell chlorinated end group molecular packing

low Concentration of Wenyang Tonglin Decoction Promotes Conjugation and Transfer of Drug-Resistant Plasmids among Heterologous Strains

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Chinese Journal of Integrative Medicine 2024年第8期30卷 721-728页

作者： WANG Bi-yan Bu Hong-shi XIA li-bo JIANG Xiang-yu TONG yan-qing Department of Traditional Chinese Medicine Changchun University of Traditional Chinese MedicineChangchun130000China

Objective To investigate the effect of low concentration of Wenyang Tonglin Decoction(WTD)on the binding conditions of R45 plasmid conjugative transfer under liquid phase conjugation and its *** Escherichia coli CP9(R45)and Staphylococcus aureus RN450RF were cul.ured in medium containing WTD,and their minimum inhibitory concentration(MIC)values were *** promoter fusion technology,*** CP9(R45)containing a promoter fusion was obtained.β-Galactosidase activity of TrfAp and TrbBp was tested,and the mRNA expression of regulatory factors(TrbA,KorA,and KorB)was detected by real-time fluorescent quantitative polymerase chain *** The MIC of *** CP9(R45)was 400 g/l and that of *** RN450RF was 200 g/*** the drug concentration in the cul.ure medium was 200 g/l,the highest number of conjugants was(3.47±0.20)×10^(7) CFu/ml At 90 h of conjugation,the maximum number of conjugants was(1.15±0.06)×10^(8) CFu/ml When the initial bacterial concentration was 10^(8) CFu/ml,the maximum number of conjugants was(3.47±0.20)×10^(7) CFu/*** the drug concentration was 200 g/l,theβ-galactosidase activity of TrfAp and TrbBp significantly increased;the relative quantification of TrbA,KorA and KorB were significantly *** low concentration of WTD promoted the development of bacterial resistance by affecting promoters and inhibiting the expression of regulatory factors.

关键词： urinary tract infection Chinese medicine drug-resistant plasmid heterozygous strains conjugation transfer

Noncoding RNAs：＇our turn＇ to join the p53 networ

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Journal of Molecular Cell Biology 2014年第3期8卷 179-180页

作者： Yong li Hua l.u Department of Biochemistry and Molecular Biology School of Medicine University of Louisville 319 Abraham Flexner Way Louisville KY40202 USA E-mail: yong.ti@louisviUe.edu Department of Biochemistry& Molecular Biology andTulane Cancer Center TulaneUniversity School ofMedicine New Orleans LA70112 USA

The p53 tumor suppressor is the guardian of the rrr- o human genome. Since ,ts discovery in pS3 has been the most studied molecule in the field of cancer. Recently, its role has also been extended to other biological and pathological processes, p53 functions primarily as a transcription factor to regulate target genes that encode proteins crucial for promot- ing apoptotic cell death, cell cycle arrest, senescence, and so on in response to diverse upstream stressors. Interestingly, some of the p53 targets are noncoding RNAs. Noncoding RNAs can be functional without being translated into proteins and are often independent RNA molecules or noncoding parts of messenger RNAs. The past decade has witnessed bur- geoning intensive investigation on the interplay of noncoding RNAs with p53, its regulators, and effectors during the development of cancer and/or other dis- eases. This issue of Journal of Molecular Cell Biology presents five essays to review the rapid progress in this area from five different angles and to offer new insight into the role of noncoding RNAs in the p53 signaling web with updated information.

关键词：非编码RNA BP网络分子细胞生物学 P53 编码蛋白质细胞周期阻滞 p53 人类基因组

Thermally-induced cracking behaviors of coal reservoirs subjected to cryogenic liquid nitrogen shock

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 2894-2908页

作者： Songcai Han Qi Gao Xinchuang yan lile li lei Wang Xian Shi Chuanliang yan Daobing Wang College of Energy Chengdu University of TechnologyChengdu610059China School of Engineering The University of Western Australia35 Stirling HighwayPerthWA6009Australia School of Petrol.um Engineering China University of Petroleum(East China)Qingdao266580China School of Mechanical Engineering Beijing Institute of Petrochemical TechnologyBeijing102617China

The benefits of using cryogenic liquid nitrogen shock to enhance coal permeability have been confirmed from experimental *** this paper,we develop a fully coupled thermo-elastic model in combination with the strain-based isotropic damage theory to uncover the cooling-dominated cracking behaviors through three typical cases,*** reservoirs containing a wellbore,a primary fracture,and a natural fracture network,*** progressive cracking processes,from thermal fracture initiation,propagation or cessation,deflection,bifurcation to multi-fracture interactions,can be well captured by the numerical *** is observed that two hierarchical levels of thermal fractures are formed,in which the number of shorter thermal fractures consistently exceeds that of the longer *** effects of coal properties related to thermal stress levels and thermal diffusivity on the fracture morphology are quantified by the fracture fractal dimension and the statistical fracture *** induced fracture morphology is most sensitive to changes in the elastic modulus and thermal expansion coefficient,both of which dominate the complexity of the fracture *** reservoir candidates with preferred thermal-mechanical properties are also recommended for improving the stimulation *** findings are that there exists a critical injection temperature and a critical in-situ stress difference,above which no thermal fractures would be *** natural fractures with higher density and preferred orientations are also essential for the formation of complex fracture *** obtained results can provide some theoretical support for cryogenic fracturing design in coal reservoirs.

关键词： Coal reservoirs Cryogenic shock Thermal cracking behaviors Fracture morphology

Surface-induced Microstructure and Performance Changes in P3HT ultrathin Films

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Chinese Journal of Polymer Science 2024年第6期42卷 805-814页

作者： Hong-Tao Shan Jia-Xin He Bing-yan Zhu Xue-Ting Cao Ying-Ying yan Jian-Jun Zhou Hong Huo Beijing Key laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing100875China

In this work,poly(3-hexylthiophene)(P3HT)ultrathin films(P3HT-T)were prepared by spin-coating a dilute P3HT solution(in a toluene:o-dichlorobenzene(Tol:ODCB)blend with a volume ratio of 80:20)with ultrasonication and the addition of the nucleating agent bicycle[2.2.1]heptane-2,3-dicarboxylic acid disodium salt(HPN-68l)on glass,Si wafers and indium tin oxide(ITO)*** electrical and mechanical properties of the P3HT-T ultrathin films were investigated,and it was found that the conductivity and crack onset strain(COS)were simultaneously improved in comparison with those of the corresponding pristine P3HT film(P3HT-0,without ultrasonication and nucleating agent)on the same substrate,regardless of what substrate was ***,the conductivity of P3HT-T ultrathin films on different substrates was similar(varying from 3.7 S·cm^(-1)to 4.4 S·cm^(-1)),yet the COS increased from 97%to 138%by varying the substrate from a Si wafer to *** grazing-incidence wide-angle X-ray diffraction(GIXRD),uV-visible(uV-Vis)spectroscopy and atomic force microscopy(AFM),we found that the solid order and crystallinity of the P3HT-T ultrathin film on the Si wafer are highest,followed by those on glass,and much lower on ***,the surface energy and roughness of three substrates were investigated,and it was found that the polar component of the surface energyγp plays a critical role in determining the crystalline microstructures of P3HT ultrathin films on different *** work indicates that the P3HT ultrathin film can obviously improve the stretchability and simultaneously retain similar electrical performance when a suitable substrate is *** findings offer a new direction for research on stretchable CP ultrathin films to facilitate future practical applications.

关键词： P3HT ultrathin film Substrate Crystalline microstructures Polar component of the surface energy Electrical and stretchable performances

Artemsieverolactones A—H,Eight Guaiane-Type Sesquiterpenoid Trimers from Artemisia sieversiana

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Chinese Journal of Chemistry 2024年第10期42卷 1084-1092页

作者： Wei Dong Xiao-yan Huang Tian-Ze li yan-Mei Weng Chang-An Geng Ji-Jun Chen State Key laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China university of Chinese Academyof Sciences Beijing 100049China

Eight new guaiane-type sesquiterpenoid trimers,artemsieverolactones A—H,possessing unprecedented scaffolds via biocatalyzed[4+2]Diels−Alder cycloaddition reactions were identified from Artemisia *** structures were determined by comprehensive spectroscopic data,single-crystal X-ray diffraction analyses,and ECD *** terms of structure,artemsieverolactones A—H are first examples of sesquiterpenoid trimers from guaiane-type sesquiterpenoid through four different[4+2]Diels−Alder cycloaddition *** fibrosis assay suggested that five compounds exhibited activity against HSC-lX2 with IC_(50)values ranging from 37.8 to 117.1μmol/*** most active artemsieverolactone B(2)displayed significant inhibitory activity against HSC-lX2 with IC_(50)value of 37.8μmol/l,which was 3 times more active than the positive drug silybin(IC_(50),139.7μmol/l).Preliminary mechanism study revealed that artemsieverolactone B could inhibit the deposition of human collagen typeⅠ(ColⅠ),human hyaluronic acid(HA),and human laminin(Hl)with IC_(50)values of 40.4μmol/l(Col I),55.1μmol/l(Hl),47.3μmol/l(HA),which was 2 to 3-fold more potent than silybin.

关键词： Artemisia sieversiana Artemsieverolactones A-H Guaiane-type sesquiterpenoid trimers Antihepatic fibrosis Extracel.ular matrix Cancer NMR spectroscopy X-ray diffraction