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A metamodeling approach for pattern specification and management

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第10期14卷 743-755页

作者： Liang DOU Qiang LIU zong-yuan yang Department of Computer Science and Technology East China Normal University

The formal specification of design patterns is central to pattern research and is the foundation of solving various pattern-related problems.In this paper,we propose a metamodeling approach for pattern specification,in which a pattern is modeled as a meta-level class and its participants are meta-level references.Instead of defining a new metamodel,we reuse the Unified Modeling Language(UML)metamodel and incorporate the concepts of Variable and Set into our approach,which are unavailable in the UML but essential for pattern specification.Our approach provides straightforward solutions for pattern-related problems,such as pattern instantiation,evolution,and implementation.By integrating the solutions into a single framework,we can construct a pattern management system,in which patterns can be instantiated,evolved,and implemented in a correct and manageable way.

关键词： Design patterns, Metamodeling, Pattern management system, Kermeta, Java modeling languages

Analytical solution for the effective elastic properties of rocks with the tilted penny-shaped cracks in the transversely isotropic background

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Petroleum Science 2024年第1期21卷 221-243页

作者： Zheng-Qian Ma Xing-Yao Yin Zhao-Yun zong yuan-yuan Tan Ya-Ming yang National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266200ShandongChina

Seismic prediction of cracks is of great significance in many disciplines,for which the rock physics model is indispensable.However,up to now,multitudinous analytical models focus primarily on the cracked rock with the isotropic background,while the explicit model for the cracked rock with the anisotropic background is rarely investigated in spite of such case being often encountered in the earth.Hence,we first studied dependences of the crack opening displacement tensors on the crack dip angle in the coordinate systems formed by symmetry planes of the crack and the background anisotropy,respectively,by forty groups of numerical experiments.Based on the conclusion from the experiments,the analytical solution was derived for the effective elastic properties of the rock with the inclined penny-shaped cracks in the transversely isotropic background.Further,we comprehensively analyzed,according to the developed model,effects of the crack dip angle,background anisotropy,filling fluid and crack density on the effective elastic properties of the cracked rock.The analysis results indicate that the dip angle and background anisotropy can significantly either enhance or weaken the anisotropy degrees of the P-and SH-wave velocities,whereas they have relatively small effects on the SV-wave velocity anisotropy.Moreover,the filling fluid can increase the stiffness coefficients related to the compressional modulus by reducing crack compliance parameters,while its effects on shear coefficients depend on the crack dip angle.The increasing crack density reduces velocities of the dry rock,and decreasing rates of the velocities are affected by the crack dip angle.By comparing with exact numerical results and experimental data,it was demonstrated that the proposed model can achieve high-precision estimations of stiffness coefficients.Moreover,the assumption of the weakly anisotropic background results in the consistency between the proposed model and Hudson's published theory for the orthorhombic rock.

关键词： Effective elastic property Tilted crack Transverse isotropy Analytical solution Crack opening displacement

LSB steganalysis of speech data based on distance measure and ML decision

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 103-107页

作者： DENG zong-yuan SHAO Xi yang Zhen Institute of Signal and Information Processing Nanjing University of Postsand Telecommunications Nanjing 210003 China

Steganalysis can be used to classify an object whether or not it contains hidden information. In this article, is presented, a novel approach to detect the presence of least significant bit（LSB） steganographic messages in the voice secure communication system. A distance measure, which has proven to be sensitive to LSB steganography by analysis of variance （ANOVA）, is denoted to estimate the difference between the host signal and the stego signal. Then an maximum likelihood （ML） decision is combined to form the classifier. Statistical experiments show that the proposed approach has a highly accurate rate and low computational complexity.

关键词： speech signal processing LSB steganography steganalysis ML decision

Basic Survey Scheduling for the Wide Field Survey Telescope(WFST)

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Research in Astronomy and Astrophysics 2024年第1期24卷 59-69页

作者： Yan-Peng Chen Ji-An Jiang Wen-Tao Luo Xian-Zhong Zheng Min Fang Chao yang yuan-Yu Hong zong-Fei Lü Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Department of Astronomy University of Science and Technology of ChinaHefei 230026China National Astronomical Observatory of Japan National Institutes of Natural Sciences2-21-1 OsawaMitakaTokyo 181-8588Japan Institute of Deep Space Sciences Deep Space Exploration LaboratoryHefei 230026China

Aiming at improving the survey efficiency of the Wide Field Survey Telescope, we have developed a basic scheduling strategy that takes into account the telescope characteristics, observing conditions, and weather conditions at the Lenghu site. The sky area is divided into rectangular regions, referred to as “tiles,” with a size of2°. 577 × 2°. 634 slightly smaller than the focal area of the mosaic CCDs. These tiles are continuously filled in annulars parallel to the equator. The brightness of the sky background, which varies with the moon phase and distance from the moon, plays a significant role in determining the accessible survey fields. Approximately 50connected tiles are grouped into one block for observation. To optimize the survey schedule, we perform simulations by taking into account the length of exposures, data readout, telescope slewing, and all relevant observing conditions. We utilize the Greedy Algorithm for scheduling optimization. Additionally, we propose a dedicated dithering pattern to cover the gaps between CCDs and the four corners of the mosaic CCD array, which are located outside of the 3° field of view. This dithering pattern helps to achieve relatively uniform exposure maps for the final survey outputs.

关键词： telescopes surveys Moon

MOF glass foam: a blueprint to porous membrane scaling-up

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Science China Chemistry 2024年第3期67卷 746-748页

作者： yuan Peng Weishen yang State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

In comparison with conventional energy-intensive separation technologies, such as distillation and crystallization,membrane separation is labelled as an advanced technology with low energy consumption, a small carbon footprint,continuous operation, etc. Metal-organic frameworks(MOFs) are a burgeoning category of crystalline materials consisting of metal ions/clusters coordinated with organic ligands.

关键词： separation porous distillation

Lactate metabolism in neurodegenerative diseases

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Neural Regeneration Research 2024年第1期19卷 69-74页

作者： Chaoguang yang Rui-yuan Pan Fangxia Guan Zengqiang yuan The Brain Science Center Beijing Institute of Basic Medical SciencesBeijingChina School of Life Sciences Zhengzhou UniversityZhengzhouHenan ProvinceChina

Lactate,a byproduct of glycolysis,was thought to be a metabolic waste until the discovery of the Warburg effect.Lactate not only functions as a metabolic substrate to provide energy but can also function as a signaling molecule to modulate cellular functions under pathophysiological conditions.The Astrocyte-Neuron Lactate Shuttle has cla rified that lactate plays a pivotal role in the central nervous system.Moreover,protein lactylation highlights the novel role of lactate in regulating transcription,cellular functions,and disease development.This review summarizes the recent advances in lactate metabolism and its role in neurodegenerative diseases,thus providing optimal pers pectives for future research.

关键词： Alzheimer's disease Astrocyte-Neuron Lactate Shuttle brain central nervous system glucose metabolism glycolysis neuroinflammation Parkinson's disease protein lactylation signaling molecule

Prescribed Performance Evolution Control for Quadrotor Autonomous Shipboard Landing

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1151-1162页

作者： yang yuan Haibin Duan Zhigang Zeng State Key Laboratory of Virtual Reality Technology and Systems the School of Automation Science and Electrical EngineeringBeihang UniversityBeijing 100083China State Key Laboratory of Virtual Reality Technology and Systems the School of Automation Science and Electrical EngineeringBeihang UniversityBeijing 100083 Virtual Reality Fundamental Research Laboratory Department of Mathematics and TheoriesPeng Cheng LaboratoryShenzhen 518000China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China

The shipboard landing problem for a quadrotor is addressed in this paper,where the ship trajectory tracking control issue is transformed into a stabilization control issue by building a relative position model.To guarantee both transient performance and steady-state landing error,a prescribed performance evolution control(PPEC)method is developed for the relative position control.In addition,a novel compensation system is proposed to expand the performance boundaries when the input saturation occurs and the error exceeds the predefined threshold.Considering the wind and wave on the relative position model,an adaptive sliding mode observer(ASMO)is designed for the disturbance with unknown upper bound.Based on the dynamic surface control framework,a shipboard landing controller integrating PPEC and ASMO is established for the quadrotor,and the relative position control error is guaranteed to be uniformly ultimately bounded.Simulation results have verified the feasibility and effectiveness of the proposed shipboard landing control scheme.

关键词： error integrating stabilization

A versatile model with three-dimensional triangular lattice for unconventional transport and various topological effects

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National Science Review 2024年第1期11卷 204-214页

作者： Jing-yang You Gang Su yuan Ping Feng Department of Physics National University of Singapore Kavli Institute for Theoretical Sciences and CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences Centre for Advanced 2D Materials National University of Singapore

The finite Berry curvature in topological materials can induce many subtle phenomena, such as the anomalous Hall effect(AHE), spin Hall effect(SHE), anomalous Nernst effect(ANE), non-linear Hall effect(NLHE) and bulk photovoltaic effects. To explore these novel physics as well as their connection and coupling, a precise and effective model should be developed. Here, we propose such a versatile model—a 3D triangular lattice with alternating hopping parameters, which can yield various topological phases,including kagome bands, triply degenerate fermions, double Weyl semimetals and so on. We reveal that this special lattice can present unconventional transport due to its unique topological surface states and the aforementioned topological phenomena, such as AHE, ANE, NLHE and the topological photocurrent effect. In addition, we also provide a number of material candidates that have been synthesized experimentally with this lattice, and discuss two materials, including a non-magnetic triangular system for SHE, NLHE and the shift current, and a ferromagnetic triangular lattice for AHE and ANE. Our work provides an excellent platform, including both the model and materials, for the study of Berry-curvature-related physics.

关键词： three-dimensional triangular lattice different topological phases various topological effects Berry curvature

Association between MTHFR c.677C>T variant and erectile dysfunction among males attending fertility clinic

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Asian Journal of Andrology 2024年第1期26卷 41-45页

作者： Shun Bai Ming-Zhen Li yang-yang Wan Xue-Chun Hu Yi-Xun Liu Xian-Hong Tong Tong-Hang Guo Lu zong Ran Liu yuan-Qi Zhao Ping Xiang Bo Xu Xiao-Hua Jiang Department of Gynecology and Obstetrics Reproductive and Genetic HospitalThe First Affiliated Hospital of University of Science and Technology of ChinaDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China NHC Key Laboratory of Male Reproduction and Genetics Guangdong Provincial Reproductive Science Institute(Guangdong Provincial Fertility Hospital)Guangzhou 510600China Department of Urology The First Affiliated Hospital of University of Science and Technology of ChinaDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Wannan Medical College Wuhu 241002China

Genetic risk factors have been shown to contribute to the development of sexual dysfunction.However,the role of methylenetetrahydrofolate reductase(MTHFR)gene variants in the risk of erectile dysfunction(ED)remains unclear.In this study,we recruited 1254 participants who underwent ED assessed by the International Index of Erectile Function-5.The MTHFR c.677C>T variant was also measured by fluorescence polymerase chain reaction(PCR).No significant difference in the genotypic frequency of the MTHFR C677T polymorphism(CC,CT,and TT)was observed between men from the ED and non-ED groups.In addition,on binary logistic regression analysis,both crude and adjusted models showed that the risk of ED was not significantly associated with the C677T polymorphism.Interestingly,a significantly higher frequency of the 677TT polymorphism was found in severe and moderate ED(P=O.02).The positive correlation between the MTHFR 677TT polymorphism and severe ED was confirmed by logistic regression analysis,even after adjusting for potential confounders(odds ratio[OR]=2.46,95%confidence interval[CI]:1.15-5.50,P=0.02).These findings suggest a positive correlation between the MTHFR 677TT polymorphism and the risk of severe ED.Identification of MTHFR gene polymorphisms may provide complementary information for ED patients during routineclinicaldiagnosis.

关键词： erectile dysfunction gene variant genetic risk factors methylenetetrahydrofolate reductase sexual function