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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 *** 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 *** 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 *** approach provides straightforward solutions for pattern-related problems,such as pattern instantiation,evolution,and *** 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

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

The In-Flight Realtime Trigger and Localization Software of GECAM

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Research in Astronomy and Astrophysics 2024年第10期 13-26页

作者： Xiao-Yun Zhao Shao-Lin Xiong Xiang-yang Wen Xin-Qiao Li Ce Cai Shuo Xiao Qi Luo Wen-Xi Peng Dong-Ya Guo Zheng-Hua An Ke Gong Jin-yuan Liao Yan-Qiu Zhang Yue Huang Lu Li Xing Wen Fei Zhang Jing Duan Chen-Wei Wang Dong-Li Shi Peng Zhang Qi-Bin Yi Chao-yang Li Yan-Bing Xu Xiao-Hua Liang Ya-Qing Liu Da-Li Zhang Xi-Lei Sun Fan Zhang Gang Chen Huan-Yu Wang Sheng yang Xiao-Jing Liu Min Gao Mao-Shun Li Jin-Zhou Wang Xing Zhou Yi Zhao Wang-Chen Xue Chao Zheng Jia-Cong Liu Xing-Bo Han Jin-Ling Qi Jia Huang Ke-Ke Zhang Can Chen Xiong-Tao yang Dong-Jie Hou Yu-Sa Wang Rui Qiao Xiang Ma Xiao-Bo Li Ping Wang Xin-Ying Song Li-Ming Song Shi-Jie Zheng Bing Li Hong-Mei Zhang Yue Zhu Wei Chen Jian-Jian He Zhen Zhang Jin Hou Hong-Jun Wang Yan-Chao Hao Xiang-Yu Wang zong-yuan yang Zhi-Long Wen Zhi Chang yuan-yuan Du Rui Gao Xiao-Fei Lan Yan-Guo Li Gang Li Xu-Fang Li Fang-Jun Lu Hong Lu Bin Meng Feng Shi Hui Wang Hui-Zhen Wang Yu-Peng Xu Jia-Wei yang Xue-Juan yang Shuang-Nan Zhang Chao-Yue Zhang Cheng-Mo Zhang Zhi-Cheng Tang Cheng Cheng Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Chinese Academy of Sciences School of Information Science and Technology Southwest Jiaotong University Key Laboratory of Stellar and Interstellar Physics and Department of Physics Xiangtan University Physics and Space Science College China West Normal University Department of Astronomy Beijing Normal University Innovation Academy for Microsatellites of CAS Changchun University of Science and Technology Chinese Academy of Sciences South America Center for Astronomy National Astronomical Observatories CAS

Realtime trigger and localization of bursts are the key functions of GECAM, an all-sky gamma-ray monitor launched on 2020 December 10. We developed a multifunctional trigger and localization software operating in the CPU of the GECAM Electronic Box. This onboard software has the following features: high trigger efficiency for real celestial bursts with a suppression of false triggers caused by charged particle bursts and background fluctuation, dedicated localization algorithm optimized for both short and long bursts, and low time latency of the trigger information which is downlinked through the Global Short Message Communication service of the global BeiDou navigation system. This paper provides a detailed description of the design and development of the trigger and localization software system for GECAM. It covers the general design, workflow, the main functions, and the algorithms used in the system. The paper also includes on-ground trigger tests using simulated gamma-ray bursts generated by a dedicated X-ray tube, as well as an overview of the performance for real celestial bursts during its in-orbit operation.

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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 ***,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 ***,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 *** 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 ***,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 *** 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 ***,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 *** increasing crack density reduces velocities of the dry rock,and decreasing rates of the velocities are affected by the crack dip *** comparing with exact numerical results and experimental data,it was demonstrated that the proposed model can achieve high-precision estimations of stiffness ***,the assumption of the weakly anisotropic background results in the consistency between the proposed model and Hudson's published theory for the or

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

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

Remote sensing image encryption algorithm utilizing 2D Logistic memristive hyperchaotic map and SHA-512

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Science China(Technological Sciences) 2024年第5期67卷 1553-1566页

作者： LAI Qiang LIU yuan yang Liang School of Electrical and Automation Engineering East China Jiaotong UniversityNanchang330013China

The two-dimensional Logistic memristive hyperchaotic map(2D-LMHM)and the secure hash SHA-512 are the foundations of the unique remote sensing image encryption algorithm(RS-IEA)suggested in this *** proposed map is formed from the improved Logistic map and the memristor,which has wide phase space and hyperchaotic range and is exceptionally excellent to be utilized in specific *** proposed image algorithm uses the permutation-assignment-diffusion *** generates two position matrices in a progressive manner to achieve an efficient random exchange of pixel positions,assignment is carried through on the image pixels of the permutated image to entirely remove the original image information,strengthening the relationship between permutation and diffusion,and loop diffusion in two different directions can use subtle changes of pixels to affect the whole *** random key and plain-image SHA-512 hash values are used to produce an additional key,which is then utilized to figure out the permutation parameters and the initial value of a chaotic *** experimental results with the average NPCR=99.6094%(NPCR:number of pixels change rate),average UACI=33.4638%(UACI:unified average changing intensity),100%pass rate of the targets in the test set,the average correlation coefficient is 0.00075,and the local information entropy is 7.9025,which shows that the algorithm is able to defend against a variety of illegal attacks and provide more trustworthy protection than some of the existing state-of-the-art algorithms.

关键词： chaos memristive hyperchaotic map remote sensing SHA-512 image encryption RS-IEA

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 *** guarantee both transient performance and steady-state landing error,a prescribed performance evolution control(PPEC)method is developed for the relative position *** addition,a novel compensation system is proposed to expand the performance boundaries when the input saturation occurs and the error exceeds the predefined *** the wind and wave on the relative position model,an adaptive sliding mode observer(ASMO)is designed for the disturbance with unknown upper *** 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 *** results have verified the feasibility and effectiveness of the proposed shipboard landing control scheme.

关键词： error integrating stabilization

Cell-free biocatalysis coupled with photo-catalysis and electro-catalysis: Efficient CO2-to-chemical conversion

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Green Energy & Environment 2024年第9期9卷 1366-1383页

作者： Junzhu yang Chi-Kit Sou yuan Lu Key Laboratory of Industrial Biocatalysis Ministry of Education Tsinghua University Department of Chemical Engineering Tsinghua University

The increasing atmospheric carbon dioxide （CO2） concentration has exposed a series of crises in the earth's ecological *** to effectively fix and convert carbon dioxide into products with added value has attracted the attention of many ***-free enzyme catalytic system coupled with electrical and light have been a promising attempt in the field of biological carbon fixation in recent *** this review,the research progresses of photoenzyme catalysis,electroenzyme catalysis and photo-electroenzyme catalysis for converting carbon dioxide into chemical products in cell-free systems are systematically *** focus on reviewing and comparing various coupling methods and principles of photoenzyme catalysis and electroenzyme catalysis in cell-free systems,especially the materials used in the construction of the coupling system,and analyze and point out the characteristics and possible problems of different coupling ***,we discuss the major challenges and prospects of coupling physical signals and cell-free enzymatic catalytic systems in the field of CO2fixation,suggesting possible strategies to improve the carbon sequestration capacity of such systems.

关键词： CO 2 fixation Cell-free system Enzyme Photoenzyme catalysis Electroenzyme catalysis