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40th IEEE International Conference on Data engineering, ICDE 2024

作者： Feng, Jieming Li, Zhanhuai Chen, Qun School of Computer Science and Engineering Northwestern Polytechnical University Shaanxi Xi'an China Key Laboratory of Big Data Storage and Management Ministry of Industry and Information Technology Northwestern Polytechnical University Shaanxi Xi'an China

ISBN: (纸本)9798350317152

SQL query optimization aims to choose an optimal Query Execution Plan (QEP) for a query. The existing optimizers usually choose the plan with the minimal execution cost. However, in some real scenarios (e.g., cloud OLAP), it is a business imperative to minimize the cost of an entire workload. Unfortunately, the greedy optimizers are prone to generating execution plans that are only suboptimal from the workload perspective. In this paper, we propose a novel QEP optimization approach for template-based SQL that aims to minimize the execution cost of an entire workload instead of individual queries. While choosing an execution plan for a query, the proposed approach considers a plan's impact on future query execution as well as its own execution cost. We first define an exploratory metric, Plan Exploration Value (PEV), to measure a plan's potential benefit to future query execution. Then, we model exploratory plan selection as an optimization problem with cost constraints, and present an efficient algorithm based on dynamic programming for its solution. Finally, we evaluate the performance of the proposed approach by a comparative study on benchmark workloads. Our extensive experiments have shown that it generates more efficient workload execution plans than the existing alternatives. © 2024 IEEE.

关键词： Dynamic programming

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Towards Seamless Wireless Link Connection 23

Towards Seamless Wireless Link Connection

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21st Annual International Conference on Mobile systems, Applications and Services, MobiSys 2023

作者： Chen, Lili Yu, Bozhong Ren, Ju Gummeson, Jeremy Zhang, Yaoxue Department of Computer Science and Technology BNRist Tsinghua University China School of Information Science and Technology Northwest University United States Department of Electrical and Computer Engineering University of Massachusetts Amherst United States Zhongguancun Laboratory Beijing China

ISBN: (纸本)9798400701108

Sub-6GHz and mmWave complement each other in the next generation of wireless communications for wide coverage and high capacity. However, there is still a gap between current network technology and seamless connection in indoor environments due to the inevitable occlusions that particularly affect higher frequency bands like Wi-Fi 5GHz and mmWave. To overcome this gap, economical tunable metasurfaces offer a promising solution by redirecting the beam direction of incoming waves to bypass blockages. However, existing metasurface technologies focus on a single frequency band and lack a theoretical framework to guide surface design for multiple desired bands, limiting their potential for diverse *** work attempts to provide a general method for cross-band metasurface design, extend wireless link coverage by using a new metasurface prototype called CrossFlit, which can maximize the link quality with efficient aperture usage and low cost. We addressed a series of challenges to enable CrossFlit to independently control the wireless communication links across multiple frequency bands;our proof of concept implementation is for Wi-Fi 5 GHz and mmWave bands. We integrate a fast beam-scanning algorithm into an end-to-end system that actuates the metasurface to optimize links in realtime. Empirical evaluation demonstrates that CrossFlit can enhance multiple wireless links simultaneously, providing 10 dB and 15 dB power improvements for Wi-Fi and mmWave links, respectively. CrossFlit achieves less than 4° beam mismatch even in challenging mobile scenarios. © 2023 Owner/Author(s)

关键词： Wi-Fi

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Evolution of supraglacial lakes over the pan-Antarctic ice sheet between 2014 and 2022: Assessment and the control factors

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Advances in Climate Change Research 2025年第2期16卷 337-349页

作者： Shen, Xiao-Yi Ke, Chang-Qing Li, Hai-Li Cai, Yu Xiao, Yao Li, Meng-Meng School of Earth Sciences and Engineering Hohai University Nanjing 211100 China Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology Key Laboratory for Land Satellite Remote Sensing Applications of Ministry of Natural Resources School of Geography and Ocean Science Nanjing University Nanjing 210023 China School of Mathematics and Statistics Zhengzhou University Zhengzhou 450001 China

Widespread supraglacial lakes (SGLs) across the Antarctic surface can accelerate land ice flow and be linked to ice shelf disintegration, further affecting sea-level rise projections. However, previous studies usually focused on SGLs at regional scale or some typical ice shelves, and underestimated the distribution and area of SGLs. Thus, the current Antarctic-wide SGL distribution and variability information is still limited, and the present status and possible influence on ice shelf stability are also largely unknown. Here, we used more than 110,000 Landsat 8 images to detect SGLs across Antarctica (north of 83°S) in austral summer from 2014 to 2022 by using a well-constructed threshold-based method. Overall, most SGLs were located on ice shelves, covering 79% of the total area;the largest SGL areas were found in East Antarctica (79%, 2222 km²), far exceeding the SGL areas in Antarctic Peninsula (20%, 473 km²) and West Antarctica (1%, 23 km²). SGL area gains and declines were found in the Antarctic Peninsula and West Antarctica, respectively, while East Antarctica experienced relatively high interannual variabilities due to the presence of some ice shelves with asynchronous variation patterns. Larger collapse risks are found for smaller ice shelves;ice shelves in East Antarctica are relatively unstable, and disintegration risk is increasing for some ice shelves in Antarctic Peninsula. Glaciological factors are closely related to the location of SGLs, and temperature, precipitation and winds are strongly linked to SGL evolution. This study is expected to enhance the reliability of existing Antarctic SGL dataset by providing a more comprehensive dataset, and offer detailed insights into the relationship between SGLs, climatic factors, and near-surface conditions. Additionally, it examines the risks of ice shelf collapse caused by SGLs, which is essential for understanding the SGL dynamics and their impacts. © 2025 The Authors

关键词： Antarctica Ice shelf collapse risk Spatio-temporal variation Supraglacial lakes

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Heavy Rainfall Prediction Model Using Sample Entropy Derived from GNSS-PWV and PSO-SVM 14th

Heavy Rainfall Prediction Model Using Sample Entropy Derived...

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14th China Satellite Navigation Conference, CSNC 2024

作者： Wu, Fanming Li, Dengao Zhao, Jinhua Feng, Ran Shi, Danyang Zhang, Xinfang Zhao, Jumin College of Data Science Taiyuan University of Technology Taiyuan030024 China College of Information and Computer Taiyuan University of Technology Taiyuan030024 China Key Laboratory of Big Data Fusion Analysis and Application of Shanxi Province Taiyuan030024 China Intelligent Perception Engineering Technology Center of Shanxi Taiyuan030024 China Shanxi Province Engineering Technology Research Center of Spatial Information Network Taiyuan030024 China

ISBN: (纸本)9789819969272

There is a growing interest to use Global Navigation Satellite system (GNSS) inversed PWV for heavy rainfall prediction. When heavy rainfall occurs, it requires the atmosphere to contain sufficient water vapour and undergo strong upward motion. However, existing models using GNSS-PWV for heavy rainfall prediction have not accounted for the effect of the complex motion of water vapour. In this paper, an hourly heavy rainfall prediction model using sample entropy derived from GNSS-PWV and PSO-SVM is proposed. The sample entropy of GNSS-PWV is used to measure the complexity of the water vapour movement process before heavy rainfall occurs. Meanwhile, combining GNSS-PWV time domain features and co-located meteorological data, the occurrence of hourly heavy rainfall events is predicted by support vector machine optimized with particle swarm. To verify the validity and feasibility of the proposed algorithm, Hong Kong's HKSC station in Sham Shui Po is used for the model to train and test. The result shows that probability of detection, false alarm rate and critical success index of the proposed algorithm in this paper have significantly improved over other heavy rainfall prediction models. © 2024, Aerospace information Research Institute.

关键词： Support vector machines

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A Drosophila-inspired intelligent olfactory biomimetic sensing system for gas recognition in complex environments

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Microsystems & Nanoengineering 2024年第5期10卷 319-330页

作者： Xiawei Yue Jiachuang Wang Heng Yang Zening Li Fangyu Zhao Wenyuan Liu Pingping Zhang Hong Chen Hanjun Jiang Nan Qin Tiger H.Tao State Key Laboratory of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China School of Graduate Study University of Chinese Academy of SciencesBeijing 100049China Suzhou Huiwen Nanotechnology Co.Ltd. Jiangsu 215004China School of Integrated Circuits Tsinghua UniversityBeijing 100084China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China 2020 X-Lab Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China Center for Excellence in Brain Science and Intelligence Technology Chinese Academy of SciencesShanghai 200031China Neuroxess Co.Ltd.(Jiangxi) NanchangJiangxi 330029China Guangdong Institute of Intelligence Science and Technology HengqinZhuhaiGuangdong 519031China OTianqiao and Chrissy Chen Institute for Translational Research ShanghaiChina

The olfactory sensory system of Drosophila has several advantages,including low power consumption,high rapidity and high ***,we present a biomimetic intelligent olfactory sensing system based on the integration of an 18-channel microelectromechanical system(MEMS)sensor array(16 gas sensors,1 humidity sensor and 1 temperature sensor),a complementary metal-oxide-semiconductor(CMOS)circuit and an olfactory lightweight machine-learning algorithm inspired by *** system is an artificial version of the biological olfactory perception system with the capabilities of environmental sensing,multi-signal processing,and odor *** olfactory data are processed and reconstructed by the combination of a shallow neural network and a residual neural network,with the aim to determine the noxious gas information in challenging environments such as high humidity scenarios and partially damaged sensor *** a result,our electronic olfactory sensing system is capable of achieving comprehensive gas recognition by qualitatively identifying 7 types of gases with an accuracy of 98.5%,reducing the number of parameters and the difficulty of calculation,and quantitatively predicting each gas of 3-5 concentration gradients with an accuracy of 93.2%;thus,these results show superiority of our system in supporting alarm systems in emergency rescue scenarios.

关键词： system environments humidity

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Fractal superconducting nanowire single-photon detector coupled with multi-mode optical fiber

Fractal superconducting nanowire single-photon detector coup...

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2024 Conference on Lasers and Electro-Optics, CLEO 2024

作者： Zou, Kai Meng, Yun Hao, Zifan Li, Jing Iovan, Adrian Descamps, Thomas Zwiller, Val Hu, Xiaolong School of Precision Instrument and Optoelectronic Engineering Tianjin University Tianjin300072 China Key Laboratory of Optoelectronic Information Science and Technology Ministry of Education Tianjin300072 China StockholmSE-106 91 Sweden

Optical absorptance of fractal SNSPDs is insensitive to the speckles in multi-mode fiber (MMF). We demonstrate 73% system detection efficiency at 1540 nm and 69 ps timing jitter with a MMF-coupled fractal SNSPD. ©... 详细信息

ISBN: (纸本)9781957171395

关键词： Timing jitter

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Modelling of Aggregates using Aperiodic Space-Filling and Physical Simulation 2

Modelling of Aggregates using Aperiodic Space-Filling and Ph...

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2021 2nd International Symposium on Automation, information and Computing, ISAIC 2021

作者： Gan, X. Ito, T. Takeshima, Y. Kikuchi, T. Graduate School of Media Science Tokyo University of Technology Hachioji Japan Department of System and Information Engineering Hachinohe Institute of Technology Hachinohe Japan School of Media Science Tokyo University of Technology Hachioji Japan

In this paper, we will explain to you how to procedural generate realistic aggregates. The program requires two or more 3D models, and the number of elements and friction values. There are two steps: the first requires user-input elements and a provided shape and fills the defined shape with non-overlapping elements;the second, together with user-input friction data, is a physical simulation to generate a more realistic pile. © Published under licence by IOP Publishing Ltd.

关键词： Aggregates

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Design of Optical Reversible Hybrid Adder-Subtractor Device Using Mach-Zehnder Interferometers for WDM Applications

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Journal of Optical Communications 2022年第4期43卷 539-548页

作者： Chauhan, Chanderkanta Kaushik, Brajesh Kumar Kumar, Santosh Department of Electrical and Electronics & Communication Engineering Dit University Uttarakhand Dehradun248009 India Shandong Key Laboratory of Optical Communication Science and Technology School of Physics Science and Information Technology Liaocheng University Liaocheng Shandong252059 China Department of Electronics and Communication Engineering Indian Institute of Technology Roorkee Uttarakhand Roorkee247667 India

As energy efficiency is one of the prominent issues in the today's era. Reversible computing may serve as a critical step toward this paramount issue. Optical reversible computing is one of the tactics to serve this aspiration. In this paper, an optical reversible hybrid adder-subtractor device delineated with the help of electro-optic effect inside lithium-niobate based Mach-Zehnder interferometer (MZI) for WDM applications. The proposed device in this work is combinational circuits and can be used as an adder as well as subtractor in advance applications. The perception is established with the help of simulation results of beam propagation method (BPM) and mathematically proven with MATLAB simulation results. © 2019 Walter de Gruyter GmbH, Berlin/Boston.

关键词： Mach-Zehnder interferometers

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WIP - Leonardo 21 Project: A New Approach

WIP - Leonardo 21 Project: A New Approach

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Frontiers in Education (FIE) Conference

作者： Claudio R Brito Melany M Ciampi Science and Education Research Organization Santos Brazil World Organization on System Engineering and Information Technology Braga Portugal

ISBN: (数字)9798350351507

ISBN: (纸本)9798350363067

This research-to-practice WIP paper describes a new educational approach for an engineering under graduation program. The willingness to grow, make difference, and impact the world is in human nature. It is the force that moves humanity ahead always full of hope for the better. engineering is a career that provides individuals the opportunity to fulfill this objective. For young men, it is the construction and transformation of the world, and for young ladies, it is the opportunity to help people on a larger scale. It has been named “Leonardo 21 Project”. It is expected to be implemented in 2025.

关键词： Economics Technological innovation Humanities engineering profession Force Mathematics Mechanical engineering Artificial intelligence Faces Investment

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Fast CU Partition for VVC Using Texture Complexity Classification Convolutional Neural Network

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Computers, Materials & Continua 2022年第11期73卷 3545-3556页

作者： Yue Zhang Pengyu Liu Xiaowei Jia Shanji Chen Tianyu Liu Chang Liu The Information Department Beijing University of TechnologyBeijing100124China School of Physics and Electronic Information Engineering Qinghai Minzu UniversityXining810000China Advanced Information Network Beijing Laboratory Beijing100124China Computational Intelligence and Intelligent Systems Beijing Key Laboratory Beijing100124China Department of Computer Science University of PittsburghPittsburgh15260USA

Versatile video coding(H.266/VVC),which was newly released by the Joint Video Exploration Team(JVET),introduces quad-tree plus multitype tree(QTMT)partition structure on the basis of quad-tree(QT)partition structure in High Efficiency Video Coding(H.265/HEVC).More complicated coding unit(CU)partitioning processes in H.266/VVC significantly improve video compression efficiency,but greatly increase the computational complexity *** ultra-high encoding complexity has obstructed its real-time *** order to solve this problem,a CU partition algorithm using convolutional neural network(CNN)is proposed in this paper to speed up the H.266/VVC CU partition ***,64×64 CU is divided into smooth texture CU,mildly complex texture CU and complex texture CU according to the CU texture ***,CU texture complexity classification convolutional neural network(CUTCC-CNN)is proposed to classify ***,according to the classification results,the encoder is guided to skip different RDO search *** optimal CU partition results will be *** results show that the proposed method reduces the average coding time by 32.2%with only 0.55%BD-BR loss compared with VTM 10.2.

关键词： Versatile video coding(VVC) coding unit partition convolutional neural network(CNN)

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