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Online estimation and characteristic analysis of double nugget diameters during aluminum/steel resistance spot welding process

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Journal of Iron and Steel Research International 2024年第8期31卷 2053-2067页

作者： Kang zhou Wen-xiao Yu Bao-kai Ren gang Wang School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

Online estimation of the double nugget diameters was performed by means of a back propagation neural *** double nugget diameters were obtained using actual welding experiment and numerical simulation,according to different characteristics of aluminum nugget and steel *** input of the neural network was some key characteristic parameters extracted from dynamic power signal,which were peak point,knee point and their variation rate over time,as well as heat energy delivered into the welding *** architecture of the neural network was confirmed by confirming the number of neurons in hidden layer through a series of *** key parameters of the neural network were obtained by means of training 81 arrays of data ***,the neural network was used to test the remaining 20 arrays of verifying data set,and the results showed that both of the mean errors for the two nugget diameters were below 3%.In addition,corresponding analyses showed that the accuracy of two nugget diameters was higher than that of tensile-shear strength.

关键词： Resistance spot welding Aluminum Steel Double nugget Dynamic power signal.Neural network

Classification of knowledge graph completeness measurement techniques

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Journal of Systems Engineering and Electronics 2024年第1期35卷 154-162页

作者： ZHANG Ying xiao gang Institute of Systems Engineering Academy of Military SciencesBeijing 100107China

At present,although knowledge graphs have been widely used in various fields such as recommendation systems,question and answer systems,and intelligent search,there are always quality problems such as knowledge omissions and *** assessment and control,as an important means to ensure the quality of knowledge,can make the applications based on knowledge graphs more complete and more accurate by reasonably assessing the knowledge graphs and fixing and improving the quality problems at the same ***,as an indispensable part of the knowledge graph construction process,the results of quality assessment and control determine the usefulness of the knowledge *** them,the assessment and enhancement of completeness,as an important part of the assessment and control phase,determine whether the knowledge graph can fully reflect objective phenomena and reveal potential connections among *** this paper,we review specific techniques of completeness assessment and classify completeness assessment techniques in terms of closed world assumptions,open world assumptions,and partial completeness *** purpose of this paper is to further promote the development of knowledge graph quality control and to lay the foundation for subsequent research on the completeness assessment of knowledge graphs by reviewing and classifying completeness assessment techniques.

关键词： quality assessment completeness assessment closed world assumptions open world assumption partial completeness assumption

Visible-light-induced organocatalyzed C（sp2）–H bond functionalization of 1,3-azoles with trifluoroacetylsilanes

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Science China Chemistry 2024年第11期67卷 3662-3668页

作者： Zhengyu Li Zeguo Zhang Zhihan Zhang gang zhou Yizhi Zhang Shanshan Liu xiao Shen The Institute for Advanced Studies Engineering Research Center of Organosilicon Compounds & Materials Ministry of EducationWuhan University College of Chemistry Central China Normal University

Previous carbene insertion to C–H bonds of 1,3-azoles relied on metal carbene species. Herein, we report a metal-free C（sp2）–H bond functionalization of 1,3-azoles with trifluoroacetylsilanes. The reaction features mild conditions, broad substrate scope and wide functional group tolerance. The mechanistic study supports that the success of the reaction is probably attributed to the dual roles of trifluoroacetylsilanes under the photocatalyzed conditions: generating carbenes which undergo cyclopropanation and generating biradicals which promote ring-opening aromatization of the in situ generated fused cyclopropanes.

关键词： C(sp2)–H bond functionalization carbenes biradicals cyclopropanation brook rearrangement

Computational Experiments for Complex Social Systems:Experiment Design and Generative Explanation

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1022-1038页

作者： xiao Xue Deyu zhou Xiangning Yu gang Wang Juanjuan Li Xia Xie Lizhen Cui Fei-Yue Wang the School of Computer Software College of Intelligence and ComputingTianjin UniversityTianjin 300350China the School of Software and the Joint SDUNTU Centre for Artificial Intelligence Research(C-FAIR) Shandong UniversityJinan 250101China the Information School Xi’an University of Financial and EconomicsXi’an 710100China the State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China Hainan University Haikou 570228China the State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 1001901China

Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a novel approach for the design,analysis,management,control,and integration of CPSS,which can realize the causal analysis of complex systems by means of“algorithmization”of“counterfactuals”.However,because CPSS involve human and social factors(e.g.,autonomy,initiative,and sociality),it is difficult for traditional design of experiment(DOE)methods to achieve the generative explanation of system *** address this challenge,this paper proposes an integrated approach to the design of computational experiments,incorporating three key modules:1)Descriptive module:Determining the influencing factors and response variables of the system by means of the modeling of an artificial society;2)Interpretative module:Selecting factorial experimental design solution to identify the relationship between influencing factors and macro phenomena;3)Predictive module:Building a meta-model that is equivalent to artificial society to explore its operating ***,a case study of crowd-sourcing platforms is presented to illustrate the application process and effectiveness of the proposed approach,which can reveal the social impact of algorithmic behavior on“rider race”.

关键词： Agent-based modeling computational experiments cyber-physical-social systems(CPSS) generative deduction generative experiments meta model

Composite laminar membranes for electricity generation from water evaporation

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Nano Research 2024年第1期17卷 307-311页

作者： xiao Wang gang Yuan Han zhou Yu Jiang Shuo Wang Jiaojiao Ma Chongyang Yang Sheng Hu State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials(iChEM)College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005China Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China

Harvesting clean energy from water evaporation has been extensively investigated due to its *** achieve high efficiency,energy conversion materials should contain multiple features which are difficult to be simultaneously obtained from single-component *** we use composite laminar membranes assembled by nanosheets of graphene oxide and mica,and find a sustained power density induced by water evaporation that is two orders of magnitude larger than that from membranes made by either of the *** power output is attributed to selective proton transport driven by water evaporation through the interlayer nanochannels in the *** process relies on the synergistic effects from negatively charged and hydrophilic mica surfaces that are important for proton selectivity and water transport,and the tunable electrical conductivity of graphene oxide that provides optimized internal *** demonstrated composite membranes offer a strategy of enhancing power generation by combining the advantages from each of their components.

关键词： graphene oxide mica water evaporation electrical double layer surface charge ion selectivity

How to implement a knowledge graph completeness assessment with the guidance of user requirements

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Journal of Systems Engineering and Electronics 2024年第3期35卷 679-688页

作者： ZHANG Ying xiao gang Institute of Systems Engineering Academy of Military SciencesBeijing 100107China

In the context of big data, many large-scale knowledge graphs have emerged to effectively organize the explosive growth of web data on the Internet. To select suitable knowledge graphs for use from many knowledge graphs, quality assessment is particularly important. As an important thing of quality assessment, completeness assessment generally refers to the ratio of the current data volume to the total data *** evaluating the completeness of a knowledge graph, it is often necessary to refine the completeness dimension by setting different completeness metrics to produce more complete and understandable evaluation results for the knowledge ***, lack of awareness of requirements is the most problematic quality issue. In the actual evaluation process, the existing completeness metrics need to consider the actual application. Therefore, to accurately recommend suitable knowledge graphs to many users, it is particularly important to develop relevant measurement metrics and formulate measurement schemes for completeness. In this paper, we will first clarify the concept of completeness, establish each metric of completeness, and finally design a measurement proposal for the completeness of knowledge graphs.

关键词： knowledge graph completeness assessment relative completeness user requirement quality management

General properties of the spectral form factor in open quantum systems

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Frontiers of physics 2024年第3期19卷 229-237页

作者： Yi-Neng zhou Tian-gang zhou Pengfei Zhang Institute for Advanced Study Tsinghua UniversityBeijing 100084China Department of Physics Fudan UniversityShanghai 200438China

The spectral form factor(SFF)can probe the eigenvalue statistic at different energy scales as its time variable *** closed quantum chaotic systems,the SFF exhibits a universal dip-ramp-plateau behavior,which reflects the spectrum rigidity of the *** this work,we explore the general properties of SFF in open quantum *** find that in open systems the SFF first decays exponentially,followed by a linear increase at some intermediate time scale,and finally decreases to a saturated plateau *** derive general relations between(i)the early-time decay exponent and Lindblad operators;(ii)the long-time plateau value and the number of steady *** also explain the effective field theory perspective of general *** verify our theoretical predictions by numerically simulating the Sachdev−Ye−Kitaev(SYK)model,random matrix theory(RMT),and the Bose−Hubbard model.

关键词： spectral form factor open quantum system quantum chaos

Eco-friendly calcium alginate microspheres enable enhanced profile control and oil displacement

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Petroleum Science 2024年第3期21卷 1928-1943页

作者： xiao-Han Zhang Chang-Jing zhou Yuan-Xiang xiao Bo Hui Yong-gang Xie Yu-Bin Su Xin-Ru Li Jie Huang Mao-Chang Liu International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi'an Jiaotong UniversityXi'an710049ShaanxiPR.China Shaanxi Key Laboratory of Advanced Stimulation Technology for Oil&Gas Reservoirs School of Petroleum EngineeringXi'an Shiyou UniversityXi'an 710065ShaanxiPR.China Oil&Gas Technology Research Institute Changqing Oilfield Branch CompanyPetroChinaXi'an710021ShaanxiPR China Suzhou Academy of Xi'an Jiaotong University Suzhou215123JiangsuPR China

Polymer microspheres(PMs),such as polyacrylamide,have been widely applied for enhanced oil recovery(EOR),yet with environmental ***,we report a microfluid displacement technology containing a bio-based eco-friendly material,i.e.,calcium alginate(CaAlg)microspheres for *** dominant mechanisms responsible for EOR over Ca Alg fluid have been verified,including the microscopic oil displacement efficacy augmented by regulating capillary force(determined by the joint action of interfacial tension and wettability between different phases)and macroscopic sweep volume increment through profile control and mobility ratio *** comprehensive effectiveness can be further impacted when the CaAlg microsphere is embellished ulteriorly by using appropriate amount of sodium dodecyl sulfonate(SDS).The core flooding and nuclear magnetic resonance(NMR)tests demonstrate that CaAlg-SDS microsphere can balance the interphase property regulation(wettability alteration and IFT reduction)and rheology properties,enabling simultaneous profile control and oil *** introduction of SDS will have a negative impact on rheological properties,which is not favored for *** results show that the involvement of 4-m M SDS will provide the best behavior,with an EOR rate of 34.38%.This cost-effective and environmentally-friendly bio-microspherebased microfluidic displacement technology is expected to achieve“green”oil recovery in future oilfield exploitation.

关键词： Calcium alginate microspheres Wettability Interfacial tension Rheology Viscoelasticity Enhanced oil recovery(EOR)

Cancer stem cells: advances in knowledge and implications for cancer therapy

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Signal Transduction and Targeted Therapy 2024年第8期9卷 3242-3304页

作者： Xianjing Chu Wentao Tian Jiaoyang Ning gang xiao Yunqi zhou Ziqi Wang Zhuofan Zhai Guilong Tanzhu Jie Yang Rongrong zhou Department of Oncology Xiangya HospitalCentral South UniversityChangsha 410008China Department of Dermatology Xiangya HospitalCentral South UniversityChangsha 410008China xiangya Lung Cancer Center Xiangya HospitalCentral South UniversityChangsha 410008China National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangshaHunan Province 410008China

Cancer stem cells(CSCs),a small subset of cells in tumors that are characterized by self-renewal and continuous proliferation,lead to tumorigenesis,metastasis,and maintain tumor *** continues to be a significant global disease *** the past,surgery,radiotherapy,and chemotherapy were the main cancer *** technology of cancer treatments continues to develop and advance,and the emergence of targeted therapy,and immunotherapy provides more options for patients to a certain ***,the limitations of efficacy and treatment resistance are still *** review begins with a brief introduction of the historical discoveries,original hypotheses,and pathways that regulate CSCs,such as WNT/β-Catenin,hedgehog,Notch,NFkB,JAK/STAT,TGF-β,PI3K/AKT,PPAR pathway,and their *** focus on the role of CSCs in various therapeutic outcomes and resistance,including how the treatments affect the content of CSCs and the alteration of related molecules,CSCs-mediated therapeutic resistance,and the clinical value of targeting CSCs in patients with refractory,progressed or advanced *** summary,CSCs affect therapeutic efficacy,and the treatment method of targeting CSCs is stll difficult to *** regulatory mechanisms and targeting biomarkers of CSCs is currently the mainstream idea.

关键词： Cancer maintain knowledge