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Spatiotemporal Evolution and Linkage Analysis of Mutton Price in Xinjiang

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Journal of Systems Science and Information 2024年

作者： Yulin YANG Jian XU Lean YU 1.School of Economics and Management, University of Chinese Academy of Sciences 2.Business School, Sichuan University 3.School of Business, Shenzhen institute of technology School of Economics and Management University of Chinese Academy of Sciences Business School Sichuan University School of Business Shenzhen Institute of Technology

The mutton industry plays a pivotal role in the animal husbandry industry of Xinjiang Uygur Autonomous Region. To better monitor the volatility movement and risk warning of mutton price, the fluctuation characteristics of mutton prices and the future trend of prices are analyzed systematically. On the one hand, the Hodrick Prescott(HP) filter method is used to analyze the longterm trends and cyclical characteristics of mutton prices in Xinjiang and explored the spatial evolution characteristics of mutton price fluctuations in various regions of Xinjiang. On the other hand, the Threshold Auto-Regressive(TAR) model is used to analyze the linkage relationship between mutton prices and the prices of other livestock products. The empirical results show that(1) the overall volatility of mutton price in Xinjiang is high, showing a trend of rising first, then falling and then rising from the temporal perspective.(2) At the regional level, the price in the south is higher than that of the north, showing a decreasing trend from south to north on the whole from the spatial viewpoint.(3) From the linkage relationship perspective, mutton and beef are complementary in the short term,but they are substitutes each other in the long term. This paper explores the characteristics of mutton price fluctuations in Xinjiang from the single time series of mutton prices and the linkage with other livestock products, which provides a reliable basis for the monitoring and risk warning of mutton price fluctuation.

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Deep Guided Attention Network for Joint Denoising and Demosaicing in Real Image

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Chinese Journal of Electronics 2024年第1期33卷 303-312页

作者： Tao ZHANG Ying FU Jun ZHANG School of Computer Science and technology Beijing Institute of Technology Advanced Reasearch institute of Multidisciplinary Science Beijing Institute of Technology

Denoising(DN) and demosaicing(DM) are the first crucial stages in the image signal processing pipeline. Recently, researches pay more attention to solve DN and DM in a joint manner, which is an extremely undetermined inverse problem. Existing deep learning methods learn the desired prior on synthetic dataset, which limits the generalization of learned network to the real world data. Moreover, existing methods mainly focus on the raw data property of high green information sampling rate for DM, but occasionally exploit the high intensity and signalto-noise(SNR) of green channel. In this work, a deep guided attention network(DGAN) is presented for real image joint DN and DM(JDD), which considers both high SNR and high sampling rate of green information for DN and DM, respectively. To ease the training and fully exploit the data property of green channel, we first train DN and DM sub-networks sequentially and then learn them jointly, which can alleviate the error accumulation. Besides, in order to support the real image JDD, we collect paired raw clean RGB and noisy mosaic images to conduct a realistic dataset. The experimental results on real JDD dataset show the presented approach performs better than the state-of-the-art methods, in terms of both quantitative metrics and qualitative visualization.

关键词： Image denoising Image demosaicing Joint processing Guided attention Paired real dataset

The safety aspect of sodium ion batteries for practical applications

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Journal of Energy Chemistry 2024年第8期95卷 407-427页

作者： Yingshuai Wang Runqing Ou Jingjing Yang Yuhang Xin Preetam Singh Feng Wu Yumin Qian Hongcai Gao School of Materials Science & Engineering Beijing Institute of Technology Department of Ceramic Engineering Indian Institute of Technology(Banaras Hindu University) Varanasi School of Physics Beijing Institute of Technology Yangtze Delta Region Academy of Beijing institute of technology Beijing institute of technology Chongqing Innovation Center

Sodium-ion batteries(SIBs) with advantages of abundant resource and low cost have emerged as promising candidates for the next-generation energy storage systems. However, safety issues existing in electrolytes, anodes, and cathodes bring about frequent accidents regarding battery fires and explosions and impede the development of high-performance SIBs. Therefore, safety analysis and high-safety battery design have become prerequisites for the development of advanced energy storage systems. The reported reviews that only focus on a specific issue are difficult to provide overall guidance for building high-safety SIBs. To overcome the limitation, this review summarizes the recent research progress from the perspective of key components of SIBs for the first time and evaluates the characteristics of various improvement strategies. By orderly analyzing the root causes of safety problems associated with different components in SIBs(including electrolytes, anodes, and cathodes), corresponding improvement strategies for each component were discussed systematically. In addition, some noteworthy points and perspectives including the chain reaction between security issues and the selection of improvement strategies tailored to different needs have also been proposed. In brief, this review is designed to deepen our understanding of the SIBs safety issues and provide guidance and assistance for designing high-safety SIBs.

关键词： Anode bulk modification Cathode bulk design Organic electrolytes modification Safety Sodium ion batteries Solid-state electrolyte

Fast Cross-Platform Binary Code Similarity Detection Framework Based on CFGs Taking Advantage of NLP and Inductive GNN

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Chinese Journal of Electronics 2024年第1期33卷 128-138页

作者： Jinxue PENG Yong WANG Jingfeng XUE Zhenyan LIU School of Computer Science and technology Beijing Institute of Technology

Cross-platform binary code similarity detection aims at detecting whether two or more pieces of binary code are similar or not. Existing approaches that combine control flow graphs(CFGs)-based function representation and graph convolutional network(GCN)-based similarity analysis are the best-performing ones. Due to a large amount of convolutional computation and the loss of structural information, the use of convolution networks will inevitably bring problems such as high overhead and sometimes inaccuracy. To address these issues, we propose a fast cross-platform binary code similarity detection framework that takes advantage of natural language processing(NLP)and inductive graph neural network(GNN) for basic blocks embedding and function representation respectively by simulating extracting structural features and temporal features. GNN’s node-centric and small batch is a suitable training way for large CFGs, it can greatly reduce computational overhead. Various NLP basic block embedding models and GNNs are evaluated. Experimental results show that the scheme with long short term memory(LSTM)for basic blocks embedding and inductive learning-based Graph SAGE(GAE) for function representation outperforms the state-of-the-art works. In our framework, we can take only 45% overhead. Improve efficiency significantly with a small performance trade-off.

关键词： Control flow graph Natural language processing Inductive graph neural network Binary code similarity detection

Portable dielectrophoresis for biology:ADEPT facilitates cell trapping,separation,and interactions

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Microsystems & Nanoengineering 2024年第2期10卷 193-205页

作者： Lourdes Albina Nirupa Julius Dora Akgül Gowri Krishnan Fabian Falk Jan Korvink Vlad Badilita Department Institute of Microstructure TechnologyKarlsruhe Institute of TechnologyHermann-von-Helmholtz-Platz 1Eggenstein-Leopoldshafen76344Baden-WürttembergGermany

Dielectrophoresis is a powerful and well-established technique that allows label-free,non-invasive manipulation of cells and particles by leveraging their electrical properties.The practical implementation of the associated electronics and user interface in a biology laboratory,however,requires an engineering background,thus hindering the broader adoption of the technique.In order to address these challenges and to bridge the gap between biologists and the engineering skills required for the implementation of DEP platforms,we report here a custom-built,compact,universal electronic platform termed ADEPT(adaptable dielectrophoresis embedded platform tool)for use with a simple microfluidic chip containing six microelectrodes.The versatility of the open-source platform is ensured by a custom-developed graphical user interface that permits simple reconfiguration of the control signals to address a wide-range of specific applications:(i)precision positioning of the single bacterium/cell/particle in the micrometer range;(ii)viability-based separation by achieving a 94%efficiency in separating live and dead yeast;(iii)phenotype-based separation by achieving a 96%efficiency in separating yeast and Bacillus subtilis;(iv)cell–cell interactions by steering a phagocytosis process where a granulocyte engulfs E.coli RGB-S bacterium.Together,the set of experiments and the platform form a complete basis for a wide range of possible applications addressing various biological questions exploiting the plug-and-play design and the intuitive GUI of ADEPT.

关键词： Together separation separating

Motion of charged particles in bright squeezed vacuum

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Light(Science & Applications) 2024年第2期13卷 347-353页

作者： Matan Even Tzur Oren Cohen Solid State institute and Physics Department Technion-Israel Institute of TechnologyHaifa3200003Israel

The motion of laser-driven electrons quivers with an average energy termed pondermotive energy.We explore electron dynamics driven by bright squeezed vacuum(BSV),finding that BSV induces width oscillations,akin to electron quivering in laser light,with an equivalent ponderomotive energy.We identify closed and open trajectories of the electronic width that are associated with high harmonic generation and above-threshold ionization,respectively,similarly to trajectories of the electron position when its motion is driven by coherent light.In the case of bound electrons,the width oscillations may lead to ionization with noisy sub-cycle structure.Our results are foundational for strong-field and free-electron quantum optics,as they shed light on ionization,high harmonic generation,and nonlinear Compton scattering in BSV.

关键词： structure vacuum ionization

Prescribed-time leader-following consensus of linear multi-agent systems by bounded linear time-varying protocols

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Science China(Information Sciences) 2024年第1期67卷 140-153页

作者： Kai ZHANG Bin ZHOU Xuefei YANG Guangren DUAN Center for Control Theory and Guidance technology Harbin Institute of Technology

This paper considers the prescribed-time leader-following consensus problem of input-constrained linear multi-agent systems under generally directed communication topology in two cases:the Laplacian matrix related to the entire communication topology between agents is either known or unknown.In particular,the consensus problem for the former case is solved by a novel bounded linear time-varying(LTV) protocol,where the feedback gain is formulated by the parametric Lyapunov equation and the knowledge of the Laplacian matrix.Moreover,by utilizing a distributed observer,a fully bounded LTV protocol is proposed for the latter case.It should be noted that,compared with the existing results,the system under consideration is more general,the designed protocols are linear,and the consensus problem is accomplished even in a fully distributed manner.Finally,the effectiveness of the proposed approach is verified by a numerical example.

关键词： leader-following consensus time-vary feedback prescribed-time control fully distributed consensus

Prescribed time control based on the periodic delayed sliding mode surface without singularities

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Science China(Information Sciences) 2024年第7期67卷 256-270页

作者： Bin ZHOU Yi DING Kang-Kang ZHANG Guang-Ren DUAN Center for Control Theory and Guidance technology Harbin Institute of Technology

In this paper, nonsingular prescribed-time control is studied based on periodic delayed sliding mode surfaces. Different from the existing sliding mode control, where either singularity problems may appear or the convergence time depends on the initial state, the proposed sliding mode control approaches can achieve prescribed-time convergence without singularity. The proposed nonsingular sliding mode control approaches can be applied to both second-order and high-order nonlinear systems with prescribed-time convergence. As applications of the proposed sliding mode control approaches, the control of hypersonic vehicle systems is revisited. Numerical simulations on the nonlinear model of the hypersonic vehicle system show the effectiveness of the proposed methods.

关键词： prescribed-time control smooth periodic delayed feedback sliding mode control high-order nonlinear systems hypersonic vehicle systems

Tower-Based Greenhouse Gas Measurement Network Design——The National institute of Standards and technology North East Corridor Testbed

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Advances in Atmospheric Sciences 2017年第9期34卷 1095-1105页

作者： Israel LOPEZ-COTO Subhomoy GHOSH Kuldeep PRASAD James WHETSTONE National institute of Standards and technology

The North-East Corridor （NEC） Testbed project is the 3rd of three NIST （National institute of Standards and technology） greenhouse gas emissions testbeds designed to advance greenhouse gas measurements capabilities. A design approach for a dense observing network combined with atmospheric inversion methodologies is described. The Advanced Research Weather Research and Forecasting Model with the Stochastic Time-Inverted Lagrangian Transport model were used to derive the sensitivity of hypothetical observations to surface greenhouse gas emissions （footprints）. Unlike other network design algorithms, an iterative selection algorithm, based on a k-means clustering method, was applied to minimize the similarities between the temporal response of each site and maximize sensitivity to the urban emissions contribution. Once a network was selected, a synthetic inversion Bayesian Kalman filter was used to evaluate observing system performance. We present the performances of various measurement network configurations consisting of differing numbers of towers and tower locations. Results show that an overly spatially compact network has decreased spatial coverage, as the spatial information added per site is then suboptimal as to cover the largest possible area, whilst networks dispersed too broadly lose capabilities of constraining flux uncertainties. In addition, we explore the possibility of using a very high density network of lower cost and performance sensors characterized by larger uncertainties and temporal drift. Analysis convergence is faster with a large number of observing locations, reducing the response time of the filter. Larger uncertainties in the observations implies lower values of uncertainty reduction. On the other hand, the drift is a bias in nature, which is added to the observations and, therefore, biasing the retrieved fluxes.

关键词： greenhouse gases network design clustering analysis Kalman filter OSSE

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