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Development in oxide metallurgy for improving the weldability of high -strength low-alloy steel-Combined deoxidizers and microalloying elements

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1263-1284页

作者： Tingting Li Jian yang State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

The mechanisms of oxide metallurgy include inducing the formation of intragranular acicular ferrite(IAF)using micron-sized inclusions and restricting the growth of prior austenite grains(PAGs)by nanosized particles during welding.The chaotically oriented IAF and refined PAGs inhibit crack initiation and propagation in the steel,resulting in high impact toughness.This work summarizes the com-bined effect of deoxidizers and alloying elements,with the aim to provide a new perspective for the research and practice related to im-proving the impact toughness of the heat affected zone(HAZ)during the high heat input welding.Ti complex deoxidation with other strong deoxidants,such as Mg,Ca,Zr,and rare earth metals(REMs),can improve the toughness of the heat-affected zone(HAZ)by re-fining PAGs or increasing IAF contents.However,it is difficult to identify the specific phase responsible for IAF nucleation because ef-fective inclusions formed by complex deoxidation are usually multiphase.Increasing alloying elements,such as C,Si,Al,Nb,or Cr,con-tents can impair HAZ toughness.A high C content typically increases the number of coarse carbides and decreases the potency of IAF formation.Si,Cr,or Al addition leads to the formation of undesirable microstructures.Nb reduces the high-temperature stability of the precipitates.Mo,V,and B can enhance HAZ toughness.Mo-containing precipitates present good thermal stability.VN or V(C,N)is ef-fective in promoting IAF nucleation due to its good coherent crystallographic relationship with ferrite.The formation of the B-depleted zone around the inclusion promotes IAF formation.The interactions between alloying elements are complex,and the effect of adding dif-ferent alloying elements remains to be evaluated.In the future,the interactions between various alloying elements and their effects on ox-ide metallurgy,as well as the calculation of the nucleation effects of effective inclusions using first principles calculations will become the focus of oxide metallurgy.

关键词： oxide metallurgy technology heat affected zone high-strength low-alloy steel intragranular acicular ferrite microalloying element

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Input-to-State Stability for Impulsive Switched Singular Systems with Mismatched Disturbances

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Journal of Systems Science & Complexity 2024年第3期37卷 924-946页

作者： yang Anqing MA Shuping School of Information Engineering Shandong Management UniversityJinan 250357China School of Mathematics Shandong UniversityJinan 250100China

This work investigates the input-to-state stability(ISS)problem for impulsive switched singular systems(ISSSs)with mismatched disturbances.In this paper,‘disturbance’is a general concept that includes model uncertainty,unknown system dynamic,external disturbance,etc.The modified uncertainty and disturbance estimator(UDE)-based control method is presented for singular systems and ISSSs,a virtual control is introduced to offset the effects of mismatched disturbances.On the basis of a discontinuous multiple Lyapunov functional and admissible edge-dependent average dwell time(AED-ADT)method,several sufficient conditions in terms of linear matrix inequalities(LMIs)are obtained to ensure that the closed-loop systems are regular,impulse-free and ISS.Finally,two examples are given to demonstrate the effectiveness of the proposed results.

关键词： Impulsive switched singular systems input-to-state stability UDE-based control

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A scoping review of methodologies for applying artificial intelligence to physical activity interventions

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Journal of Sport and Health Science 2024年第3期13卷 428-441页

作者： Ruopeng An Jing Shen Junjie Wang Yuyi yang Brown School Washington UniversitySt.LouisMO 63130USA Department of Physical Education China University of Geosciences BeijingBeijing 100083China School of Kinesiology and Health Promotion Dalian University of TechnologyDalian 116024China Division of Computational and Data Sciences Washington UniversitySt.LouisMO 63130USA

Purpose This scoping review aimed to offer researchers and practitioners an understanding of artificial intelligence(AI)applications in physical activity(PA)interventions;introduce them to prevalent machine learning(ML),deep learning(DL),and reinforcement learning(RL)algorithms;and encourage the adoption of AI methodologies.Methods A scoping review was performed in PubMed,Web of Science,Cochrane Library,and EBSCO focusing on AI applications for promoting PA or predicting related behavioral or health outcomes.AI methodologies were summarized and categorized to identify synergies,patterns,and trends informing future research.Additionally,a concise primer on predominant AI methodologies within the realm of PA was provided to bolster understanding and broader application.Results The review included 24 studies that met the predetermined eligibility criteria.AI models were found effective in detecting significant patterns of PA behavior and associations between specific factors and intervention outcomes.Most studies comparing AI models to traditional statistical approaches reported higher prediction accuracy for AI models on test data.Comparisons of different AI models yielded mixed results,likely due to model performance being highly dependent on the dataset and task.An increasing trend of adopting state-of-the-art DL and RL models over standard ML was observed,addressing complex human–machine communication,behavior modification,and decision-making tasks.Six key areas for future AI adoption in PA interventions emerged:personalized PA interventions,real-time monitoring and adaptation,integration of multimodal data sources,evaluation of intervention effectiveness,expanding access to PA interventions,and predicting and preventing injuries.Conclusion The scoping review highlights the potential of AI methodologies for advancing PA interventions.As the field progresses,staying informed and exploring emerging AI-driven strategies is essential for achieving significant improvements in PA interventions and fostering overall we

关键词： Artificial intelligence Intervention Machine learning Neural network Physical activity

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Sparse Reconstructive Evidential Clustering for Multi-View Data

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 459-473页

作者： Chaoyu Gong yang You School of Computing National University of SingaporeSingapore

Although many multi-view clustering(MVC) algorithms with acceptable performances have been presented, to the best of our knowledge, nearly all of them need to be fed with the correct number of clusters. In addition, these existing algorithms create only the hard and fuzzy partitions for multi-view objects,which are often located in highly-overlapping areas of multi-view feature space. The adoption of hard and fuzzy partition ignores the ambiguity and uncertainty in the assignment of objects, likely leading to performance degradation. To address these issues, we propose a novel sparse reconstructive multi-view evidential clustering algorithm(SRMVEC). Based on a sparse reconstructive procedure, SRMVEC learns a shared affinity matrix across views, and maps multi-view objects to a 2-dimensional humanreadable chart by calculating 2 newly defined mathematical metrics for each object. From this chart, users can detect the number of clusters and select several objects existing in the dataset as cluster centers. Then, SRMVEC derives a credal partition under the framework of evidence theory, improving the fault tolerance of clustering. Ablation studies show the benefits of adopting the sparse reconstructive procedure and evidence theory. Besides,SRMVEC delivers effectiveness on benchmark datasets by outperforming some state-of-the-art methods.

关键词： Evidence theory multi-view clustering(MVC) optimization sparse reconstruction

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An improved initial rotor position estimation method using high-frequency pulsating voltage injection for PMSM

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Defence Technology（防务技术） 2024年第3期33卷 19-29页

作者： yang Jiang Ming Cheng School of Electrical Engineering Southeast UniversityNanjing 210096China

High frequency pulsating voltage injection method is a good candidate for detecting the initial rotor position of permanent magnet synchronous motor.However,traditional methods require a large number of filters,which leads to the deterioration of system stability and dynamic performance.In order to solve these problems,a new signal demodulation method is proposed in this paper.The proposed new method can directly obtain the amplitude of high-frequency current,thus eliminating the use of filters,improving system stability and dynamic performance and saving the work of adjusting filter parameters.In addition,a new magnetic polarity detection method is proposed,which is robust to current measurement noise.Finally,experiments verify the effectiveness of the method.

关键词： Initial position detection Signal demodulation algorithm Magnetic polarity detection Filter elimination

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High-pressure minerals and new lunar mineral changesite-(Y) in Chang’e-5 regolith

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Matter and Radiation at Extremes 2024年第2期9卷 90-97页

作者： Jing yang Wei Du Center for Lunar and Planetary Sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of Sciences(CAS)Guiyang 550081China CAS Center for Excellence in Comparative Planetology Hefei 230026China

Forty-five years after the Apollo and Luna missions, China’s Chang’e-5 (CE-5) mission collected ∼1.73 kg of new lunar materials from one ofthe youngest basalt units on the Moon. The CE-5 lunar samples provide opportunities to address some key scientific questions related to theMoon, including the discovery of high-pressure silica polymorphs (seifertite and stishovite) and a new lunar mineral, changesite-(Y). Seifertitewas found to be coexist with stishovite in a silica fragment from CE-5 lunar regolith. This is the first confirmed seifertite in returned lunarsamples. Seifertite has two space group symmetries (Pnc2 and Pbcn) and formed from an α-cristobalite-like phase during “cold” compressionduring a shock event. The aftershock heating process changes some seifertite to stishovite. Thus, this silica fragment records different stagesof an impact process, and the peak shock pressure is estimated to be ∼11 to 40 GPa, which is much lower than the pressure condition forcoexistence of seifertite and stishovite on the phase diagram. Changesite-(Y), with ideal formula (Ca_(8)Y)◻Fe^(2+)(PO_(4))_(7) (where ◻ denotes avacancy) is the first new lunar mineral to be discovered in CE-5 regolith samples. This newly identified phosphate mineral is in the form ofcolumnar crystals and was found in CE-5 basalt fragments. It contains high concentrations of Y and rare earth elements (REE), reaching upto ∼14 wt. % (Y,REE)2O3. The occurrence of changesite-(Y) marks the late-stage fractional crystallization processes of CE-5 basalts combinedwith silicate liquid immiscibility. These new findings demonstrate the significance of studies on high-pressure minerals in lunar materials andthe special nature of lunar magmatic evolution.

关键词： evolution minerals basalt

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Large language model and domain-specific model collaboration for smart education

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Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 333-341页

作者： Yawei LUO Yi yang School of Software Technology Zhejiang UniversityNingbo 315048China College of Computer Science and Technology Zhejiang UniversityHangzhou 310027China

In this paper,we introduce the large language model and domain-specific model collaboration(LDMC)framework designed to enhance smart education.The LDMC framework leverages the comprehensive and versatile knowledge of large domain-general models,combines it with the specialized and disciplinary knowledge from small domainspecific models(DSMs),and incorporates pedagogy knowledge from learning theory models.This integration yields multiple knowledge representations,fostering personalized and adaptive educational experiences.We explore various applications of the LDMC framework in the context of smart education.

关键词： smart language knowledge

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Study of 26 Galactic Open Clusters with Extended Main-sequence Turnoffs

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Research in Astronomy and Astrophysics 2024年第6期24卷 30-39页

作者： yang-yang Deng Zhong-Mu Li Yunnan Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences Institute of Astronomy and Information Dali University

Recent studies indicate that some Galactic open clusters(OCs) exhibit extended main-sequence turnoff(eMSTO)in their color–magnitude diagrams(CMDs). However, the number of Galactic OCs with eMSTO structures detected so far is limited, and the reasons for their formation are still unclear. This work identifies 26 Galactic OCs with undiscovered eMSTOs and investigates the causes of these features. Stellar population types and fundamental parameters of cluster samples are acquired using CMD fitting methods. Among them, the results of 11 OCs are reliable as the observed CMDs are well-reproduced. We propose the crucial role of stellar binarity and confirm the importance of stellar rotation in reproducing eMSTO morphologies. The results also show that the impact of age spread is important, as it can adequately explain the structure of young OCs and fit the observed CMDs of intermediate-age OCs better.

关键词： (Galaxy:) open clusters and associations: general (stars:) binaries: general (stars:) Hertzsprung-Russell and C-M-diagrams Galaxy: fundamental parameters

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Colony-stimulating factor-1 receptor inhibition combined with paclitaxel exerts effective antitumor effects in the treatment of ovarian cancer

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Genes & Diseases 2024年第3期11卷 400-416页

作者： Meijia Yu Yiming Wu Qingfang Li Weiqi Hong yang yang Xiaoyi Hu Yanfei yang Tianqi Lu Xia Zhao Xiawei Wei Laboratory of Aging Research and Cancer Drug Target State Key Laboratory of Biotherapy and Cancer CenterNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengduSichuan 610041China Department of Gynecology and Obstetrics Development and Related Disease of Women and Children Key Laboratory of Sichuan ProvinceKey Laboratory of Birth Defects and Related Diseases of Women and ChildrenMinistry of EducationWest China Second HospitalSichuan UniversityChengduSichuan 610041China Department of Obstetrics and Gynecology The First Affiliated HospitalArmy Medical UniversityChongqing 400038China

Ovarian cancer is the tumor with the highest mortality among gynecological malig-nancies.Studies have confirmed that paclitaxel chemoresistance is associated with increased infiltration of tumor-associated macrophages(TAMs)in the microenvironment.Colony-stimu-lating factor 1(CSF-1)receptor(CSF-1R)plays a key role in regulating the number and differ-entiation of macrophages in certain solid tumors.There are few reports on the effects of targeted inhibition of CSF-1R in combination with chemotherapy on ovarian cancer and the tu-mor microenvironment.Here,we explored the antitumor efficacy and possible mechanisms of the CSF-1R inhibitor pexidartinib(PLX3397)when combined with the first-line chemothera-peutic agent paclitaxel in the treatment of ovarian cancer.We found that CSF-1R is highly ex-pressed in ovarian cancer cells and correlates with poor prognosis.Treatment by PLX3397 in combination with paclitaxel significantly inhibited the growth of ovarian cancer both in vitro and in vivo.Blockade of CSF-1R altered the macrophage phenotype and reprogrammed the immunosuppressive cell population in the tumor microenvironment.

关键词： CSF-1R Ovariancancer Paclitaxel PLX3397 Targeted therapy Tumor-associated macrophages

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An anti-collision algorithm for robotic search-and-rescue tasks in unknown dynamic environments

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 569-584页

作者： yang CHEN Dianxi SHI Huanhuan yang Tongyue LI Zhen WANG School of Computer Science Peking UniversityBeijing 100871China Tianjin Artificial Intelligence Innovation Center Tianjin 300457China Intelligent Game and Decision Lab Beijing 100071China College of Computer National University of Defense TechnologyChangsha 410073China

This paper deals with the search-and-rescue tasks of a mobile robot with multiple interesting targets in an unknown dynamic environment.The problem is challenging because the mobile robot needs to search for multiple targets while avoiding obstacles simultaneously.To ensure that the mobile robot avoids obstacles properly,we propose a mixed-strategy Nash equilibrium based Dyna-Q(MNDQ)algorithm.First,a multi-objective layered structure is introduced to simplify the representation of multiple objectives and reduce computational complexity.This structure divides the overall task into subtasks,including searching for targets and avoiding obstacles.Second,a risk-monitoring mechanism is proposed based on the relative positions of dynamic risks.This mechanism helps the robot avoid potential collisions and unnecessary detours.Then,to improve sampling efficiency,MNDQ is presented,which combines Dyna-Q and mixed-strategy Nash equilibrium.By using mixed-strategy Nash equilibrium,the agent makes decisions in the form of probabilities,maximizing the expected rewards and improving the overall performance of the Dyna-Q algorithm.Furthermore,a series of simulations are conducted to verify the effectiveness of the proposed method.The results show that MNDQ performs well and exhibits robustness,providing a competitive solution for future autonomous robot navigation tasks.

关键词： Search and rescue Reinforcement learning Game theory Collision avoidance Decision-making

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