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Communications in Theoretical Physics 2006年第5X期46卷 843-844页

作者： LAI Mei-Mei WANG xin XIAO Yan-ping liu Quan-Hui School for Theoretical Physics and Department of Applied Physics Hunan University Changsha 410082 China

When the motion of a particle is constrained, excess terms exist using hermitian form of Cartesian momentum pi （i=1, 2,3） in usual kinetic energy （1/2/μ）∑ pi^2 , and the correct kinetic energy turns out to be （1/2μ） ∑1/ fipi f ipi, where fi are dummy factors in classical mechanics and nontrivial in quantum mechanics. In this paper the explicit form of the dummy functions fi is given for a charged rigid planar rotator in the uniform magnetic field with different gauge chosen. Under different gauges, we have different sets of dummy factors. It means that these factors do not have direct observable effect.

关键词： operator ordering gauge transformation quantum mechanics

Rapid prediction of damaged ship roll motion responses in beam waves based on stacking algorithm

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Journal of Hydrodynamics 2024年第2期36卷 394-405页

作者： xin-ran liu Ting-qiu Li Zi-ping Wang School of Naval Architecture Ocean and Energy Power EngineeringWuhan University of TechnologyWuhan430063China

Accurate modeling for highly non-linear coupling of a damaged ship with liquid sloshing in waves is still of considerable interest within the computational fluid dynamics(CFD)and AI *** paper describes a data-driven Stacking algorithm for fast prediction of roll motion response amplitudes in beam waves by constructing a hydrodynamics model of a damaged ship based on the dynamic overlapping grid CFD *** general idea is to optimize various parameters varying with four types of classical base models like multi-layer perception,support vector regression,random forest,and hist gradient boosting *** offers several attractive properties in terms of accuracy and efficiency by choosing the standard DTMB 5415 model with double damaged compartments for *** is clearly demonstrated that the predicted response amplitude operator(RAO)in the regular beam waves agrees well with the experimental data available,which verifies the accuracy of the established damaged ship hydrodynamics *** high-quality CFD samples,therefore,implementation of the designed Stacking algorithm with its optimal combination can predict the damaged ship roll motion amplitudes effectively and accurately(e.g.,the coefficient of determination 0.9926,the average absolute error 0.0955 and CPU 3s),by comparison of four types of typical base models and their various ***,the established Stacking algorithm provides one potential that can break through problems involving the time-consuming and low efficiency for large-scale lengthy CFD simulations.

关键词： Ship motion damaged ship computational fluid dynamics(CFD) machine learning stacking algorithm

Control Strategies for Digital Twin Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 170-180页

作者： Guo-ping liu IEEE the Center for Control Science and Technology Southern University of Science and TechnologyShenzhen 518055China

With the continuous breakthrough in information technology and its integration into practical applications, industrial digital twins are expected to accelerate their development in the near future. This paper studies various control strategies for digital twin systems from the viewpoint of practical *** make full use of advantages of digital twins for control systems, an architecture of digital twin control systems, adaptive model tracking scheme, performance prediction scheme, performance retention scheme, and fault tolerant control scheme are proposed. Those schemes are detailed to deal with different issues on model tracking, performance prediction, performance retention, and fault tolerant control of digital twin systems. Also, the stability of digital twin control systems is analysed. The proposed schemes for digital twin control systems are illustrated by examples.

关键词： Digital twin control systems fault tolerant control model tracking performance prediction performance retention

Cloning of the kininogen gene from Lampetra japonica provides insights into its phylogeny in vertebrates

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Journal of Genetics and Genomics 2009年第2期36卷 109-115页

作者： Liwei Zhou xin liu ping Jin Qingwei Li College of Life Sciences Liaoning Normal University Dalian 116029 China

Kininogens, the precursors of bradykinins, ubiquitously exist in vertebrates, including mammals, birds, amphibians, and fishes. To elucidate the phylogeny of kininogen genes in early vertebrates, we cloned the full-length cDNA of kininogen gene from the liver of Lampetra japonica. The open reading frame of this sequence contained 546 bp and encoded 181 amino acids, including a cystatin domain without the canonical binding site for cysteine proteinases and a bradykinin domain. Our results suggested that in lampreys and most of other vertebrates, there might be only one kininogen gene, which was fused by certain sequences during vertebrate evolution and encoded proteins with more functions; however, another special kininogen gene, only encoding the bradykinin domain with multiple copies in some species, arose only in amphibians for adapting themselves to the unique environment. Using reverse transcription PCR, kininogen mRNA was also detected in lamprey gut, kidney, and leukocyte, but absent in lamprey buccal gland. Our findings may provide insights into the phylogeny of kininogen genes as well as other gene families in vertebrates.

关键词： kininogen Lampetrajaponica phylogeny bradykinin domain cystatin domain tissue distribution

Combinatorial reasoning-based abnormal sensor recognition method for subsea production control system

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Petroleum Science 2024年第4期21卷 2758-2768页

作者： Rui Zhang Bao-ping Cai Chao Yang Yu-Ming Zhou Yong-Hong liu xin-Yang Qi College of Mechanical and Electronic Engineering China University of Petroleum BGP Inc. China National Petroleum Corporation

The subsea production system is a vital equipment for offshore oil and gas production. The control system is one of the most important parts of it. Collecting and processing the signals of subsea sensors is the only way to judge whether the subsea production control system is normal. However, subsea sensors degrade rapidly due to harsh working environments and long service time. This leads to frequent false alarm incidents. A combinatorial reasoning-based abnormal sensor recognition method for subsea production control system is proposed. A combinatorial algorithm is proposed to group sensors. The long short-term memory network(LSTM) is used to establish a single inference model. A counting-based judging method is proposed to identify abnormal sensors. Field data from an offshore platform in the South China Sea is used to demonstrate the effect of the proposed method. The results show that the proposed method can identify the abnormal sensors effectively.

关键词： Abnormal sensor Combinatorial algorithm Fault identification Subsea production control system

Mesenchymal stem cells for repairing glaucomatous optic nerve

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 748-760页

作者： Bai-Yu Hu Mei xin Ming Chen ping Yu liu-Zhi Zeng Eye School of Chengdu University of TCM Chengdu 610000Sichuan ProvinceChina Department of Ophthalmology Chengdu First People’s HospitalChengdu 610095Sichuan ProvinceChina

Glaucoma is a common and complex neurodegenerative disease characterized by progressive loss of retinal ganglion cells(RGCs)and ***,there is no effective method to address the cause of RGCs ***,studies on neuroprotective strategies for optic neuropathy have increased in recent *** replacement and neuroprotection are major strategies for treating glaucoma and optic *** medicine research into the repair of optic nerve damage using stem cells has Received considerable *** cells possess the potential for multidirectional differentiation abilities and are capable of producing RGCfriendly microenvironments through paracrine *** article reviews a thorough researches of recent advances and approaches in stem cell repair of optic nerve injury,raising the controversies and unresolved issues surrounding the future of stem cells.

关键词： stem cell glaucoma retinal ganglion cell optic nerve axon regeneration

Privacy-Preserving Consensus-Based Distributed Economic Dispatch of Smart Grids via State Decomposition

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1250-1261页

作者： Wei Chen Guo-ping liu The authors are with the Center for Control Science and Technology Southern University of Science and TechnologyShenzhen 518055China

This paper studies the privacy-preserving distributed economic dispatch(DED)problem of smart *** autonomous consensus-based algorithm is developed via local data exchange with neighboring nodes,which covers both the islanded mode and the grid-connected mode of smart *** prevent power-sensitive information from being disclosed,a privacy-preserving mechanism is integrated into the proposed DED algorithm by randomly decomposing the state into two parts,where only partial data is *** objective is to develop a privacy-preserving DED algorithm to achieve optimal power dispatch with the lowest generation cost under physical constraints while preventing sensitive information from being *** this end,a comprehensive analysis framework is established to ensure that the proposed algorithm can converge to the optimal solution of the concerned optimization problem by means of the consensus theory and the eigenvalue perturbation *** particular,the proposed autonomous algorithm can achieve a smooth transition between the islanded mode and the grid-connected ***,rigorous analysis is given to show privacy-preserving performance against internal and external ***,case studies illustrate the feasibility and validity of the developed algorithm.

关键词： preserving autonomous mode

Mechanical characteristics and reservoir stimulation mechanisms of the Gulong shale oil reservoirs, the northern Songliao Basin

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Petroleum Science 2024年第3期21卷 2023-2036页

作者： Si-Wei Meng Jia-ping Tao Tian-Jiao Li Dong-Xu Li Su-Ling Wang liu Yang xin liu Li-Hao Liang He liu PetroChina Research Institute of Petroleum Exploration Development Beijing100083China National Key Laboratory of Continental Shale Oil Daqing 163002HeilongjiangChina Dalian University of Technology Dalian116024LiaoningChina PetroChina Daqing Oilfield Co.Ltd. Daqing163002HeilongjiangChina Northeast Petroleum University Daqing163002HeilongjiangChina China University of Mining and Technology(Beijing) Beijing100083China

Shale oil of the Qingshankou Formation of the Gulong Sag,the northern Songliao Basin,represents the first attempt at large-scale development of pure-shale-type shale oil in *** integrating the multiscale refined reservoir characterization with macro-micro-scale mechanical testing,it is clarified that the Gulong shale is characterized by high clay mineral content,high rock plasticity,highly-developed bedding,and prominent mechanical anisotropy.A three-dimensional(3D)fracture propagation model of hydraulic fracturing was built for the Gulong shale,which fully captures the hydraulic fracture distribution pattern affected by the high bedding density,in-situ stress,and fracturing treatment *** research showed that due to influences of bedding,hydraulic fracturing in the Gulong shale forms a complex fracture morphology featuring the main fracture with multiple perpendicular branches that have different lengths(like the outdoor directional TV antenna);however,the vertical propagation of fractures is inhibited,and the fracture height is commonly less than 10 *** limited stimulated reservoir volume(SRV)is the main problem facing the fracturing stimulation of the Gulong shale *** density has vital effects on fracture morphology,so case-specific fracturing designs shall be developed for shale intervals with different bedding development *** reservoirs with welldeveloped bedding,it is suggested to properly increase the perforation cluster spacing and raise the volume and proportions of viscous fluids of the pad,so as to effectively promote vertical fracture propagation and improve reservoir stimulation *** study integrates multi-scale fine reservoir characterization and macro-micro-scale mechanical testing,as well as the construction and numerical simulation of hydraulic fracturing models for high-density layered shale reservoirs,providing a new approach and methodological framework for the fracturing research of high-density layer

关键词： Shale oil Hydraulic fracturing High bedding density Fracture propagation model

Socioeconomic traits and the risk of Barrett’s esophagus and gastroesophageal reflux disease: A Mendelian randomization study

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2631-2645页

作者： Yu-xin liu Cheng-Li Bin Lu Zhang Wen-Tao Yang Bai-ping An Department of Oncology Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina Department of Gynecology and Obstetrics Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina Department of Endocrine Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina Department of Cardiovascular Chengdu Integrated TCM&Western Medicine HospitalChengdu 610041Sichuan ProvinceChina

BACKGROUND Previous observational studies have shown that the prevalence of gastroesophageal reflux disease(GERD)and Barrett’s esophagus(BE)is associated with socioeconomic ***,due to the methodological limitations of traditional observational studies,it is challenging to definitively establish *** To explore the causal relationship between the prevalence of these conditions and socioeconomic status using Mendelian randomization(MR).METHODS We initially screened single nucleotide polymorphisms(SNPs)to serve as proxies for eight socioeconomic status phenotypes for univariate MR *** inverse variance weighted(IVW)method was used as the primary analytical method to estimate the causal relationship between the eight socioeconomic status phenotypes and the risk of GERD and *** then collected combinations of SNPs as composite proxies for the eight socioeconomic phenotypes to perform multivariate MR(MVMR)analyses based on the IVW MVMR ***,a two-step MR mediation analysis was used to examine the potential mediation of the associations by body mass index,major depressive disorder(MDD),smoking,alcohol consumption,and sleep *** The study identified three socioeconomic statuses that had a significant impact on *** included household income[odds ratio(OR):0.46;95% confidence interval(95%CI):0.31-0.70],education attainment(OR:0.23;95%CI:0.18-0.29),and the Townsend Deprivation Index at recruitment(OR:1.57;95%CI:1.04-2.37).These factors were found to independently and predominantly influence the genetic causal effect of ***,the mediating effect of educational attainment on GERD was found to be mediated by MDD(proportion mediated:10.83%).Similarly,the effect of educational attainment on BE was mediated by MDD(proportion mediated:10.58%)and the number of cigarettes smoked per day(proportion mediated:3.50%).Additionally,the mediating effect of household income on GERD was observed to be mediated by sleep dur

关键词： Socioeconomic status Gastroesophageal reflux disease Barrett’s esophagus Two-step Mendelian randomization Multivariate Mendelian randomization

Immunolocalization assessment of metastasis-associated protein I in human and mouse mature testes and its association with spermatogenesis

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Asian Journal of Andrology 2007年第3期9卷 345-352页

作者： Wei Li xin-ping liu Ruo-Jun Xu Yuan-Qiang Zhang Department of Histology and Embryology The Fourth Military Medical University Xi＇an 710032 China Department of Biochemistry and Molecular Biology The Fourth Military Medical University Xi＇an 710032 China Department of Zoology University of Hong Kong Hong Kong China

Aim： To investigate the stage-specific localization of metastasis-associated protein 1 （MTA1） during spermatogenesis in adult human and mouse testis. Methods： The immunolocalization of MTA1 was studied by immunohistochemistry and Western blot analysis. The distribution pattern of MTA1 in mouse testis was confirmed by using quantitative analysis of purified spermatogenic cells. Results： The specificity of polyclonal antibody was confirmed by Western blot analysis. MTA1 was found expressed in the nucleus of germ cells, except elongate spermatids, and in the cytoplasm of Sertoli cells; Leydig cells did not show any specific reactivity. MTA1 possessed different distribution patterns in the two species： in humans, the most intensive staining was found in the nucleus of round spermatids and of primary spermatocytes while in mice, the most intense MTA 1 staining was in the nucleus of leptotene, zygotene and pachytene spermatocytes. In both species the staining exhibited a cyclic pattern. Conclusion： The present communication initially provides new evidence for the potential role of MTA1 in mature testis. In addition, its distinctive expression in germ cells suggests a regulatory role of the peptide during spermatogenesis.

关键词： human metastasis-associated proteinl mouse metastasis-associated protein 1 spermatogenesis nuclear remodeling anddeacetylation complex chromatin remodeling spermiogenesis deacetylation