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Deciphering and integrating invariants for neural operator learning with various physical mechanisms

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National Science Review 2024年第4期11卷 111-122页

作者： rui Zhang Qi Meng zhi-Ming ma Academy of mathematics and Systems Science Chinese Academy of Sciences(CAS) Microsoft Research

Neural operators have been explored as surrogate models for simulating physical systems to overcome the limitations of traditional partial differential equation(PDE) solvers. However, most existing operator learning methods assume that the data originate from a single physical mechanism, limiting their applicability and performance in more realistic scenarios. To this end, we propose the physical invariant attention neural operator(PIANO) to decipher and integrate the physical invariants for operator learning from the PDE series with various physical mechanisms. PIANO employs self-supervised learning to extract physical knowledge and attention mechanisms to integrate them into dynamic convolutional *** to existing techniques, PIANO can reduce the relative error by 13.6%–82.2% on PDE forecasting tasks across varying coefficients, forces or boundary conditions. Additionally, varied downstream tasks reveal that the PI embeddings deciphered by PIANO align well with the underlying invariants in the PDE systems, verifying the physical significance of PIANO.

关键词： neural operator PDE solver contrastive learning physical invariants

The Multi-parameter Test of Gravitational Wave Dispersion with Principal Component Analysis

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Research in Astronomy and Astrophysics 2024年第5期24卷 140-150页

作者： zhi-Chu ma rui Niu Wen Zhao CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

In this work, we consider a conventional test of gravitational wave(GW) propagation which is based on the phenomenological parameterized dispersion relation to describe potential departures from General Relativity(GR)along the propagation of GWs. But different from tests conventionally performed previously, we vary multiple deformation coefficients simultaneously and employ the principal component analysis(PCA) method to remedy the strong degeneracy among deformation coefficients and obtain informative posteriors. The dominant PCA components can be better measured and constrained, and thus are expected to be more sensitive to potential departures from the waveform model. Using this method we analyze ten selected events and get the result that the combined posteriors of the dominant PCA parameters are consistent with GR within 99.7% credible intervals. The standard deviation of the first dominant PCA parameter is three times smaller than that of the original dispersion parameter of the leading order. However, the multi-parameter test with PCA is more sensitive to not only potential deviations from GR but also systematic errors of waveform models. The difference in results obtained by using different waveform templates hints that the demands of waveform accuracy are higher to perform the multiparameter test with PCA. Whereas, it cannot be strictly proven that the deviation is indeed and only induced by systematic errors. It requires more thorough research in the future to exclude other possible reasons in parameter estimation and data processing.

关键词： gravitational waves-gravitation-black hole physics

Multi-scale data joint inversion of minerals and porosity in altered igneous reservoirs—A case study in the South China Sea

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Petroleum Science 2024年第1期21卷 206-220页

作者： Xin-ru Wang Bao-zhi Pan Yu-Hang Guo Qing-Hui Wang Yao Guan College of Geo-exploration Science and Technology Jilin UniversityChangchun130046JilinChina Research Institute CNOOC Ltd.-ShenzhenShenzhen518000GuangdongChina

There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir ***,affected by the diverse lithology,complicated mineral and widespread alteration,conventional logging lithology classification and mineral inversion become considerably *** the same time,owing to the limitation of the wireline log response equation,the quantity and accuracy of minerals can hardly meet the exploration requirements of igneous *** overcome those issues,this study takes the South China Sea as an example,and combines multi-scale data such as micro rock slices,petrophysical experiments,wireline log and element cutting log to establish a set of joint inversion methods for minerals and porosity of altered igneous ***,we define the lithology and mineral characteristics through core slices and mineral data,and establish an igneous multi-mineral volumetric *** we determine element cutting log correction method based on core element data,and combine wireline log and corrected element cutting log to perform the lithology classification and joint inversion of minerals and ***,it is always difficult to determine the elemental eigenvalues of different minerals in *** paper uses multiple linear regression methods to solve this ***,an integrated inversion technique for altered igneous formations was *** results show that the corrected element cutting log are in good agreement with the core element data,and the mineral and porosity results obtained from the joint inversion based on the wireline log and corrected element cutting log are also in good agreement with the core data from X-ray *** results demonstrate that the inversion technique is applicable and this study provides a new direction for the mineral inversion research of altered igneous formation

关键词： Joint inversion Altered igneous rock Element correction method Lithology identification Multi mineral volume model

magnetic emission intensity enhancement for amorphous alloys by constructing a multi-phase structure withα-Fe nanocrystals

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Nano Research 2024年第7期17卷 6630-6637页

作者： Ke Liu zhi Qin Jie Shen zhi Cheng Shiyue You Liang ma Jing Zhou Wen Chen State Key Laboratory of Advanced Technology for materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China Sanya Science and Education Innovation Park Wuhan University of TechnologySanya 572024China Hubei Longzhong Laboratory Wuhan University of Technology Xiangyang Demonstration ZoneXiangyang 441000China

The perturbation in the magnetic field generated by the rotation or oscillation of magnetic domains in magnetic materials can emit low-frequency electromagnetic waves,which are expected to be used in low-frequency ***,the magnetic emission intensity,defined by the perturbation ability,of current commercially applied amorphous alloys,such as Metglas,cannot meet the application requirements for low-frequency antennas due to the domain motion energy ***,a multi-phase Metglas amorphous alloy was constructed by incorporatingα-Fe nanocrystals using rapid annealing to manipulate the domain *** was found that 3.89 times higher magnetic emission intensity is obtained compared to the pristine due to the synergism of the deformation and displacement ***,the low-frequency magnetic emission performance verification was carried out by preparing magnetoelectric composites as the antenna vibrator by assembling the alloy and macro piezoelectric fiber composites(MFC).Enhancements of magnetic emission intensity are found at 93.3%and 49.2%at the first and second harmonic frequencies compared with the unmodified alloy ***,the approach leads to the development of high-performance communication with a novel standard for evaluation.

关键词： multi-phase amorphous alloys magnetic emission intensity enhancing mechanism magnetic domain pinning theory Jiles-Atherton model analysis

Liquid-phase epitaxial layer by layer brushing fabrication of metalorganic frameworks films

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Nano Research 2024年第6期17卷 5698-5704页

作者： Li-Mei Chang rui Zhai zhi-Zhou ma Jian-Dong Huang zhi-Gang Gu Jian Zhang College of Chemistry Fuzhou UniversityFuzhou 350108China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China

Development of metal-organic framework(MOF)films is of great importance to expand their ***,we report a facile and universal method of liquid-phase epitaxial(LPE)layer by layer(LBL)brushing approach for fabricating MOF films on various substrates in a high-throughput *** MOF films preparation method offers a great prospective to cost-effectively construct films with short preparation time and little reagent ***,this LBL brushing approach has been implemented successfully to assemble various MOF films,including HKUST-1,zeolitic imidazolate framework-8(ZIF-8),Cu(bdc),and Cu_(2)(L)_(2)P(L=bdc,ndc,and cam;P=dabco and bipy).Afterwards,the classic MOF HKUST-1 and ZIF-8 films were grown on sensor chip electrode and porous fiber support for good volatile organic compounds(VOCs)selective sensing and water purification *** study demonstrates that this LBL brushing preparation method can be employed to synthesize various MOF films with a variety of characteristics to realize their sensing and separation applications.

关键词： metal-organic framework porous materials layer by layer fabrication film

Which Factors Influence the Effect of Deep Synthesized Video Propagation

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Journal of Systems Science and Information 2024年第3期12卷 393-411页

作者： Lixia ma Jingjing WANG Yiwei ru Yunjie WEI School of Economics and management University of Chinese Academy of SciencesBeijing 100190China School of Economics and Finance Xi'an Jiaotong UniversityXi'an 710061China Institute of Automation Chinese Academy of SciencesBeijing 100190China Academy of mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China

Deep synthesis technology is an emerging artificial intelligence *** have been a large number of audio and video contents based on deep synthesis technology spreading in the *** this paper,we take the deep synthetic videos on YouTube platform as the research object,and investigate the factors influencing the propagation effect of deep synthetic videos by establishing an ordered probit *** is found that the effect of deep synthesized video transmission of YouTube platform is mainly influenced by factors such as the video type,video duration,influence of publishers and forms of *** addition,the comparative analysis of ordinary video and in-depth synthesized video reveals that both the video transmission effect are significantly affected by the video type,video duration and the influence of publishers.

关键词： deep synthesized video transmission effect ordered probit model

Near-infrared non-fused electron acceptors for efficient organic photovoltaics

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Chinese Chemical Letters 2024年第4期35卷 436-441页

作者： Wenxiang ma Xinyu He Tianyi Chen De-Li ma Hongzheng Chen Chang-zhi Li State Key Laboratory of Silicon and Advanced Semiconductor materials Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

Developing narrow-bandgap organic semiconductors is important to facilitate the advancement of organic photovoltaics(OPVs). Herein, two near-infrared non-fused ring acceptors(NIR NFRAs), PTBFTT-F and PTBFTT-Cl have been developed with A-π_A-π_D-D-π_D-π_A-A non-fused structures. It is revealed that the introduction of electron deficient π-bridge(π_A) and multiple intramolecular noncovalent interactions effectively retained the structural planarity and intramolecular charge transfer of NFRAs, extending strong NIR photon absorption up to 950 nm. Further, the chlorinated acceptor, with the enlarged π-surface compared to the fluorinated counterpart, promoted not only molecular stacking in solid, but also the desirable photochemical stability in ambient, which are helpful to thereby improve the exciton and charge dynamics for the corresponding OPVs. Overall, this work provides valuable insights into the design of NIR organic semiconductors.

关键词： Organic photovoltaic Near-infrared Non-fused electron acceptor Noncovalent interaction Stability

Age of Information for Short-Packet Covert Communication with Time Modulated Retrodirective Array

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China Communications 2024年第4期21卷 23-37页

作者： ma Yue ma ruiqian Lin zhi Yang Weiwei Cai Yueming Miao Chen Wu Wen Key Laboratory of Near-Range RF Sensing ICs&Microsystems(NJUST) Ministry of EducationSchool of Electronic and Optical EngineeringNanjing University of Science and TechnologyNanjing 210094China College of Electronic Engineering National University of Defense TechnologyHefei 230037China College of Communications Engineering Army Engineering University of PLANanjing 210007China

In this paper,the covert age of information(CAoI),which characterizes the timeliness and covertness performance of communication,is first investigated in the short-packet covert communication with time modulated retrodirective array(TMRDA).Specifically,the TMRDA is designed to maximize the antenna gain in the target direction while the side lobe is sufficiently *** this basis,the covertness constraint and CAoI are derived in closed *** facilitate the covert transmission design,the transmit power and block-length are jointly optimized to minimize the CAoI,which demonstrates the trade-off between covertness and *** results illustrate that there exists an optimal block-length that yields the minimum CAoI,and the presented optimization results can achieve enhanced performance compared with the fixed block-length ***,we observe that smaller beam pointing error at Bob leads to improvements in CAoI.

关键词： age of information covert communication retrodirective array time modulation

Overview of the immunological mechanisms in hepatitis B virus reactivation:Implications for disease progression and management strategies

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World Journal of Gastroenterology 2024年第10期30卷 1295-1312页

作者： Hui ma Qing-Zhu Yan Jing-ru ma Dong-Fu Li Jun-Ling Yang Department of Clinical Laboratory The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Ultrasound Medicine The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Digestive Diseases Center Department of Hepatopancreatobiliary MedicineThe Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Respiratory and Critical Care Medicine The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina

Hepatitis B virus(HBV)reactivation is a clinically significant challenge in disease *** review explores the immunological mechanisms underlying HBV reactivation,emphasizing disease progression and *** delves into host immune responses and reactivation’s delicate balance,spanning innate and adaptive *** factors’disruption of this balance,as are interac-tions between viral antigens,immune cells,cytokine networks,and immune checkpoint pathways,are ***,the roles of T cells,natural killer cells,and antigen-presenting cells are discussed,highlighting their influence on disease *** reactivation’s impact on disease severity,hepatic flares,liver fibrosis progression,and hepatocellular carcinoma is *** strategies,including anti-viral and immunomodulatory approaches,are critically *** role of prophylactic anti-viral therapy during immunosuppressive treatments is explored alongside novel immunotherapeutic interventions to restore immune control and prevent *** conclusion,this compre-hensive review furnishes a holistic view of the immunological mechanisms that propel HBV *** a dedicated focus on understanding its implic-ations for disease progression and the prospects of efficient management stra-tegies,this article contributes significantly to the knowledge *** more profound insights into the intricate interactions between viral elements and the immune system will inform evidence-based approaches,ultimately enhancing disease management and elevating patient *** dynamic landscape of management strategies is critically scrutinized,spanning anti-viral and immunomodulatory *** role of prophylactic anti-viral therapy in preventing reactivation during immunosuppressive treatments and the potential of innovative immunotherapeutic interventions to restore immune control and proactively deter reactivation.

关键词： Hepatitis B virus reactivation Immunological mechanisms Disease progression management strategies Immune response